Polymorphic cells that form cartilage.
A protective layer of firm, flexible cartilage over the articulating ends of bones. It provides a smooth surface for joint movement, protecting the ends of long bones from wear at points of contact.
A non-vascular form of connective tissue composed of CHONDROCYTES embedded in a matrix that includes CHONDROITIN SULFATE and various types of FIBRILLAR COLLAGEN. There are three major types: HYALINE CARTILAGE; FIBROCARTILAGE; and ELASTIC CARTILAGE.
The area between the EPIPHYSIS and the DIAPHYSIS within which bone growth occurs.
A progressive, degenerative joint disease, the most common form of arthritis, especially in older persons. The disease is thought to result not from the aging process but from biochemical changes and biomechanical stresses affecting articular cartilage. In the foreign literature it is often called osteoarthrosis deformans.
A fibrillar collagen found predominantly in CARTILAGE and vitreous humor. It consists of three identical alpha1(II) chains.
A secreted matrix metalloproteinase that plays a physiological role in the degradation of extracellular matrix found in skeletal tissues. It is synthesized as an inactive precursor that is activated by the proteolytic cleavage of its N-terminal propeptide.
Large HYALURONAN-containing proteoglycans found in articular cartilage (CARTILAGE, ARTICULAR). They form into aggregates that provide tissues with the capacity to resist high compressive and tensile forces.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The formation of cartilage. This process is directed by CHONDROCYTES which continually divide and lay down matrix during development. It is sometimes a precursor to OSTEOGENESIS.
Glycoproteins which have a very high polysaccharide content.
A non-fibrillar collagen found primarily in terminally differentiated hypertrophic CHONDROCYTES. It is a homotrimer of three identical alpha1(X) subunits.
A SOXE transcription factor that plays a critical role in regulating CHONDROGENESIS; OSTEOGENESIS; and male sex determination. Loss of function of the SOX9 transcription factor due to genetic mutations is a cause of CAMPOMELIC DYSPLASIA.
Macromolecular organic compounds that contain carbon, hydrogen, oxygen, nitrogen, and usually, sulfur. These macromolecules (proteins) form an intricate meshwork in which cells are embedded to construct tissues. Variations in the relative types of macromolecules and their organization determine the type of extracellular matrix, each adapted to the functional requirements of the tissue. The two main classes of macromolecules that form the extracellular matrix are: glycosaminoglycans, usually linked to proteins (proteoglycans), and fibrous proteins (e.g., COLLAGEN; ELASTIN; FIBRONECTINS; and LAMININ).
Heteropolysaccharides which contain an N-acetylated hexosamine in a characteristic repeating disaccharide unit. The repeating structure of each disaccharide involves alternate 1,4- and 1,3-linkages consisting of either N-acetylglucosamine or N-acetylgalactosamine.
A slowly growing malignant neoplasm derived from cartilage cells, occurring most frequently in pelvic bones or near the ends of long bones, in middle-aged and old people. Most chondrosarcomas arise de novo, but some may develop in a preexisting benign cartilaginous lesion or in patients with ENCHONDROMATOSIS. (Stedman, 25th ed)
A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).
The growth and development of bones from fetus to adult. It includes two principal mechanisms of bone growth: growth in length of long bones at the epiphyseal cartilages and growth in thickness by depositing new bone (OSTEOGENESIS) with the actions of OSTEOBLASTS and OSTEOCLASTS.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
A meshwork-like substance found within the extracellular space and in association with the basement membrane of the cell surface. It promotes cellular proliferation and provides a supporting structure to which cells or cell lysates in culture dishes adhere.
Noninflammatory degenerative disease of the knee joint consisting of three large categories: conditions that block normal synchronous movement, conditions that produce abnormal pathways of motion, and conditions that cause stress concentration resulting in changes to articular cartilage. (Crenshaw, Campbell's Operative Orthopaedics, 8th ed, p2019)
Pathological processes involving the chondral tissue (CARTILAGE).
An extracellular endopeptidase of vertebrate tissues similar to MATRIX METALLOPROTEINASE 1. It digests PROTEOGLYCAN; FIBRONECTIN; COLLAGEN types III, IV, V, and IX, and activates procollagenase. (Enzyme Nomenclature, 1992)
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
An interleukin-1 subtype that is synthesized as an inactive membrane-bound pro-protein. Proteolytic processing of the precursor form by CASPASE 1 results in release of the active form of interleukin-1beta from the membrane.
The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
A soluble factor produced by MONOCYTES; MACROPHAGES, and other cells which activates T-lymphocytes and potentiates their response to mitogens or antigens. Interleukin-1 is a general term refers to either of the two distinct proteins, INTERLEUKIN-1ALPHA and INTERLEUKIN-1BETA. The biological effects of IL-1 include the ability to replace macrophage requirements for T-cell activation.
Generating tissue in vitro for clinical applications, such as replacing wounded tissues or impaired organs. The use of TISSUE SCAFFOLDING enables the generation of complex multi-layered tissues and tissue structures.
Salts of alginic acid that are extracted from marine kelp and used to make dental impressions and as absorbent material for surgical dressings.
Enzymes that catalyze the degradation of collagen by acting on the peptide bonds.
A natural high-viscosity mucopolysaccharide with alternating beta (1-3) glucuronide and beta (1-4) glucosaminidic bonds. It is found in the UMBILICAL CORD, in VITREOUS BODY and in SYNOVIAL FLUID. A high urinary level is found in PROGERIA.
The process of bone formation. Histogenesis of bone including ossification.
Cartilage of the EAR AURICLE and the EXTERNAL EAR CANAL.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
Abnormal development of cartilage and bone.
General increase in bulk of a part or organ due to CELL ENLARGEMENT and accumulation of FLUIDS AND SECRETIONS, not due to tumor formation, nor to an increase in the number of cells (HYPERPLASIA).
The five long bones of the METATARSUS, articulating with the TARSAL BONES proximally and the PHALANGES OF TOES distally.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
In horses, cattle, and other quadrupeds, the joint between the femur and the tibia, corresponding to the human knee.
PROTEOGLYCANS-associated proteins that are major components of EXTRACELLULAR MATRIX of various tissues including CARTILAGE; and INTERVERTEBRAL DISC structures. They bind COLLAGEN fibers and contain protein domains that enable oligomer formation and interaction with other extracellular matrix proteins such as CARTILAGE OLIGOMERIC MATRIX PROTEIN.
A sugar acid formed by the oxidation of the C-6 carbon of GLUCOSE. In addition to being a key intermediate metabolite of the uronic acid pathway, glucuronic acid also plays a role in the detoxification of certain drugs and toxins by conjugating with them to form GLUCURONIDES.
An extracellular endopeptidase which excises a block of peptides at the amino terminal, nonhelical region of the procollagen molecule with the formation of collagen. Absence or deficiency of the enzyme causes accumulation of procollagen which results in the inherited connective tissue disorder--dermatosparaxis. EC 3.4.24.14.
A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principle cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX.
A potent osteoinductive protein that plays a critical role in the differentiation of osteoprogenitor cells into OSTEOBLASTS.
Term used to designate tetrahydroxy aldehydic acids obtained by oxidation of hexose sugars, i.e. glucuronic acid, galacturonic acid, etc. Historically, the name hexuronic acid was originally given to ascorbic acid.
A member of the metalloproteinase family of enzymes that is principally responsible for cleaving FIBRILLAR COLLAGEN. It can degrade interstitial collagens, types I, II and III.
A fibril-associated collagen usually found crosslinked to the surface of COLLAGEN TYPE II fibrils. It is a heterotrimer containing alpha1(IX), alpha2(IX) and alpha3(IX) subunits.
Methods for maintaining or growing CELLS in vitro.
A synovial hinge connection formed between the bones of the FEMUR; TIBIA; and PATELLA.
The head of a long bone that is separated from the shaft by the epiphyseal plate until bone growth stops. At that time, the plate disappears and the head and shaft are united.
Process by which organic tissue becomes hardened by the physiologic deposit of calcium salts.
A ubiquitously expressed, secreted protein with bone resorption and renal calcium reabsorption activities that are similar to PARATHYROID HORMONE. It does not circulate in appreciable amounts in normal subjects, but rather exerts its biological actions locally. Overexpression of parathyroid hormone-related protein by tumor cells results in humoral calcemia of malignancy.
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
The inner membrane of a joint capsule surrounding a freely movable joint. It is loosely attached to the external fibrous capsule and secretes SYNOVIAL FLUID.
A transcription factor that dimerizes with CORE BINDING FACTOR BETA SUBUNIT to form core binding factor. It contains a highly conserved DNA-binding domain known as the runt domain and is involved in genetic regulation of skeletal development and CELL DIFFERENTIATION.
Bone-growth regulatory factors that are members of the transforming growth factor-beta superfamily of proteins. They are synthesized as large precursor molecules which are cleaved by proteolytic enzymes. The active form can consist of a dimer of two identical proteins or a heterodimer of two related bone morphogenetic proteins.
A reverse developmental process in which terminally differentiated cells with specialized functions revert back to a less differentiated stage within their own CELL LINEAGE.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
The second longest bone of the skeleton. It is located on the medial side of the lower leg, articulating with the FIBULA laterally, the TALUS distally, and the FEMUR proximally.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Sepharose is a brand name for a type of cross-linked agarose gel beads used as a matrix in chromatography and other biochemical procedures, known for their high porosity, mechanical stability, and low non-specific binding, making them suitable for various purification and analytical applications.
A class of animal lectins that bind to carbohydrate in a calcium-dependent manner. They share a common carbohydrate-binding domain that is structurally distinct from other classes of lectins.
A factor synthesized in a wide variety of tissues. It acts synergistically with TGF-alpha in inducing phenotypic transformation and can also act as a negative autocrine growth factor. TGF-beta has a potential role in embryonal development, cellular differentiation, hormone secretion, and immune function. TGF-beta is found mostly as homodimer forms of separate gene products TGF-beta1, TGF-beta2 or TGF-beta3. Heterodimers composed of TGF-beta1 and 2 (TGF-beta1.2) or of TGF-beta2 and 3 (TGF-beta2.3) have been isolated. The TGF-beta proteins are synthesized as precursor proteins.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
A family of zinc-dependent metalloendopeptidases that is involved in the degradation of EXTRACELLULAR MATRIX components.
A type of CARTILAGE characterized by a homogenous amorphous matrix containing predominately TYPE II COLLAGEN and ground substance. Hyaline cartilage is found in ARTICULAR CARTILAGE; COSTAL CARTILAGE; LARYNGEAL CARTILAGES; and the NASAL SEPTUM.
Also known as articulations, these are points of connection between the ends of certain separate bones, or where the borders of other bones are juxtaposed.
A set of twelve curved bones which connect to the vertebral column posteriorly, and terminate anteriorly as costal cartilage. Together, they form a protective cage around the internal thoracic organs.
Derivatives of chondroitin which have a sulfate moiety esterified to the galactosamine moiety of chondroitin. Chondroitin sulfate A, or chondroitin 4-sulfate, and chondroitin sulfate C, or chondroitin 6-sulfate, have the sulfate esterified in the 4- and 6-positions, respectively. Chondroitin sulfate B (beta heparin; DERMATAN SULFATE) is a misnomer and this compound is not a true chondroitin sulfate.
A family of low-molecular weight, non-histone proteins found in chromatin.
Glucosamine is a naturally occurring amino sugar that plays a crucial role in the formation and maintenance of various tissues, particularly in the synthesis of proteoglycans and glycosaminoglycans, which are essential components of cartilage and synovial fluid in joints.
The most common and most biologically active of the mammalian prostaglandins. It exhibits most biological activities characteristic of prostaglandins and has been used extensively as an oxytocic agent. The compound also displays a protective effect on the intestinal mucosa.
Cell growth support structures composed of BIOCOMPATIBLE MATERIALS. They are specially designed solid support matrices for cell attachment in TISSUE ENGINEERING and GUIDED TISSUE REGENERATION uses.
Bone-marrow-derived, non-hematopoietic cells that support HEMATOPOETIC STEM CELLS. They have also been isolated from other organs and tissues such as UMBILICAL CORD BLOOD, umbilical vein subendothelium, and WHARTON JELLY. These cells are considered to be a source of multipotent stem cells because they include subpopulations of mesenchymal stem cells.
Bone-forming cells which secrete an EXTRACELLULAR MATRIX. HYDROXYAPATITE crystals are then deposited into the matrix to form bone.
An autosomal dominant disorder that is the most frequent form of short-limb dwarfism. Affected individuals exhibit short stature caused by rhizomelic shortening of the limbs, characteristic facies with frontal bossing and mid-face hypoplasia, exaggerated lumbar lordosis, limitation of elbow extension, GENU VARUM, and trident hand. (Online Mendelian Inheritance in Man, http://www.ncbi.nlm.nih.gov/Omim, MIM#100800, April 20, 2001)
Inorganic salts of sulfuric acid.
A family of membrane-anchored glycoproteins that contain a disintegrin and metalloprotease domain. They are responsible for the proteolytic cleavage of many transmembrane proteins and the release of their extracellular domain.
An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.1.
A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.
The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.
All of the processes involved in increasing CELL NUMBER including CELL DIVISION.
The maximum compression a material can withstand without failure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p427)
Major component of chondrocyte EXTRACELLULAR MATRIX of various tissues including bone, tendon, ligament, SYNOVIUM and blood vessels. It binds MATRILIN PROTEINS and is associated with development of cartilage and bone.
Water swollen, rigid, 3-dimensional network of cross-linked, hydrophilic macromolecules, 20-95% water. They are used in paints, printing inks, foodstuffs, pharmaceuticals, and cosmetics. (Grant & Hackh's Chemical Dictionary, 5th ed)
A technique for maintaining or growing TISSUE in vitro, usually by DIFFUSION, perifusion, or PERFUSION. The tissue is cultured directly after removal from the host without being dispersed for cell culture.
A family of intercellular signaling proteins that play and important role in regulating the development of many TISSUES and organs. Their name derives from the observation of a hedgehog-like appearance in DROSOPHILA embryos with genetic mutations that block their action.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
A growth differentiation factor that plays a role in early CHONDROGENESIS and joint formation.
A fibroblast growth factor receptor that regulates CHONDROCYTE growth and CELL DIFFERENTIATION. Mutations in the gene for fibroblast growth factor receptor 3 have been associated with ACHONDROPLASIA; THANATOPHORIC DYSPLASIA and NEOPLASTIC CELL TRANSFORMATION.
A genetic or pathological condition that is characterized by short stature and undersize. Abnormal skeletal growth usually results in an adult who is significantly below the average height.
A bone morphogenetic protein that is widely expressed during EMBRYONIC DEVELOPMENT. It is both a potent osteogenic factor and a specific regulator of nephrogenesis.
An enzyme that catalyzes the random hydrolysis of 1,4-linkages between N-acetyl-beta-D-glucosamine and D-glucuronate residues in hyaluronate. (From Enzyme Nomenclature, 1992) There has been use as ANTINEOPLASTIC AGENTS to limit NEOPLASM METASTASIS.
A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
Thin outer membrane that surrounds a bone. It contains CONNECTIVE TISSUE, CAPILLARIES, nerves, and a number of cell types.
A plant genus in the LAURACEAE family. The tree, Persea americana Mill., is known for the Avocado fruit, the food of commerce.
A well-characterized basic peptide believed to be secreted by the liver and to circulate in the blood. It has growth-regulating, insulin-like, and mitogenic activities. This growth factor has a major, but not absolute, dependence on GROWTH HORMONE. It is believed to be mainly active in adults in contrast to INSULIN-LIKE GROWTH FACTOR II, which is a major fetal growth factor.
Membrane proteins that are involved in the active transport of phosphate.
A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.
A subclass of closely-related SOX transcription factors. In addition to a conserved HMG-BOX DOMAIN, members of this group contain a leucine zipper motif which mediates protein DIMERIZATION.
A long, narrow, and flat bone commonly known as BREASTBONE occurring in the midsection of the anterior thoracic segment or chest region, which stabilizes the rib cage and serves as the point of origin for several muscles that move the arms, head, and neck.
The posterior process on the ramus of the mandible composed of two parts: a superior part, the articular portion, and an inferior part, the condylar neck.
A fibrillar collagen found primarily in interstitial CARTILAGE. Collagen type XI is heterotrimer containing alpha1(XI), alpha2(XI) and alpha3(XI) subunits.
Unstable isotopes of sulfur that decay or disintegrate spontaneously emitting radiation. S 29-31, 35, 37, and 38 are radioactive sulfur isotopes.
The most common form of fibrillar collagen. It is a major constituent of bone (BONE AND BONES) and SKIN and consists of a heterotrimer of two alpha1(I) and one alpha2(I) chains.
Inflammation of a bone and its overlaying CARTILAGE.
A parathyroid hormone receptor subtype that recognizes both PARATHYROID HORMONE and PARATHYROID HORMONE-RELATED PROTEIN. It is a G-protein-coupled receptor that is expressed at high levels in BONE and in KIDNEY.
Bone in humans and primates extending from the SHOULDER JOINT to the ELBOW JOINT.
A cytokine with both pro- and anti-inflammatory actions that depend upon the cellular microenvironment. Oncostatin M is a 28 kDa monomeric glycoprotein that is similar in structure to LEUKEMIA INHIBITORY FACTOR. Its name derives from the the observation that it inhibited the growth of tumor cells and augmented the growth of normal fibroblasts.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.
The longest and largest bone of the skeleton, it is situated between the hip and the knee.
Proteoglycans consisting of proteins linked to one or more CHONDROITIN SULFATE-containing oligosaccharide chains.
Developmental bone diseases are a category of skeletal disorders that arise from disturbances in the normal growth and development of bones, including abnormalities in size, shape, structure, or composition, which can lead to various musculoskeletal impairments and deformities.
Proteases which use a metal, normally ZINC, in the catalytic mechanism. This group of enzymes is inactivated by metal CHELATORS.
An articulation between the condyle of the mandible and the articular tubercle of the temporal bone.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
A copper-containing dye used as a gelling agent for lubricants, for staining of bacteria and for the dyeing of histiocytes and fibroblasts in vivo.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.
The process by which cells convert mechanical stimuli into a chemical response. It can occur in both cells specialized for sensing mechanical cues such as MECHANORECEPTORS, and in parenchymal cells whose primary function is not mechanosensory.
An inducibly-expressed subtype of prostaglandin-endoperoxide synthase. It plays an important role in many cellular processes and INFLAMMATION. It is the target of COX2 INHIBITORS.
A subtype of transforming growth factor beta that is synthesized by a wide variety of cells. It is synthesized as a precursor molecule that is cleaved to form mature TGF-beta 1 and TGF-beta1 latency-associated peptide. The association of the cleavage products results in the formation a latent protein which must be activated to bind its receptor. Defects in the gene that encodes TGF-beta1 are the cause of CAMURATI-ENGELMANN SYNDROME.
A mitogen-activated protein kinase subfamily that regulates a variety of cellular processes including CELL GROWTH PROCESSES; CELL DIFFERENTIATION; APOPTOSIS; and cellular responses to INFLAMMATION. The P38 MAP kinases are regulated by CYTOKINE RECEPTORS and can be activated in response to bacterial pathogens.
A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.
A biosynthetic precursor of collagen containing additional amino acid sequences at the amino-terminal and carboxyl-terminal ends of the polypeptide chains.
A mucopolysaccharide constituent of chondrin. (Grant & Hackh's Chemical Dictionary, 5th ed)
A physiologically active metabolite of VITAMIN D. The compound is involved in the regulation of calcium metabolism, alkaline phosphatase activity, and enhances the calcemic effect of CALCITRIOL.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Elements of limited time intervals, contributing to particular results or situations.
The clear, viscous fluid secreted by the SYNOVIAL MEMBRANE. It contains mucin, albumin, fat, and mineral salts and serves to lubricate joints.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in enzyme synthesis.
Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.

Cloning of a novel gene specifically expressed in clonal mouse chondroprogenitor-like EC cells, ATDC5. (1/3820)

We cloned a full-length cDNA encoding a novel mouse protein, A-C2, by differential display method using mouse embryonic fibroblast C3H10T1/2 cells and mouse chondroprogenitor-like EC cells, ATDC5. The deduced amino acid sequence of A-C2 consisted of 106 amino acids with no significant homology to the sequences previously reported. Northern blot analysis showed two major bands of 2.1 and 1.8 kb sizes. Expression of A-C2 mRNA was exclusive to ATDC5 cells at their undifferentiated stage. None of ATDC5 cells at their differentiated stage and adult mice tissues examined expressed A-C2 gene.  (+info)

Inhibition of transforming growth factor beta production by nitric oxide-treated chondrocytes: implications for matrix synthesis. (2/3820)

OBJECTIVE: Nitric oxide (NO) is generated copiously by articular chondrocytes activated by interleukin-1beta (IL-1beta). If NO production is blocked, much of the IL-1beta inhibition of proteoglycan synthesis is prevented. We tested the hypothesis that this inhibitory effect of NO on proteoglycan synthesis is secondary to changes in chondrocyte transforming growth factor beta (TGFbeta). METHODS: Monolayer, primary cultures of lapine articular chondrocytes and cartilage slices were studied. NO production was determined as nitrite accumulation in the medium. TGFbeta bioactivity in chondrocyte- and cartilage-conditioned medium (CM) was measured with the mink lung epithelial cell bioassay. Proteoglycan synthesis was measured as the incorporation of 35S-sodium sulfate into macromolecules separated from unincorporated label by gel filtration on PD-10 columns. RESULTS: IL-1beta increased active TGFbeta in chondrocyte CM by 12 hours; by 24 hours, significant increases in both active and latent TGFbeta were detectable. NG-monomethyl-L-arginine (L-NMA) potentiated the increase in total TGFbeta without affecting the early TGFbeta activation. IL-1beta stimulated a NO-independent, transient increase in TGFbeta3 at 24 hours; however, TGFbeta1 was not changed. When NO synthesis was inhibited with L-NMA, IL-1beta increased CM concentrations of TGFbeta1 from 24-72 hours of culture. L-arginine (10 mM) reversed the inhibitory effect of L-NMA on NO production and blocked the increases in TGFbeta1. Anti-TGFbeta1 antibody prevented the restoration of proteoglycan synthesis by chondrocytes exposed to IL-1beta + L-NMA, confirming that NO inhibition of TGFbeta1 in IL-1beta-treated chondrocytes effected, in part, the decreased proteoglycan synthesis. Furthermore, the increase in TGFbeta and proteoglycan synthesis seen with L-NMA was reversed by the NO donor S-nitroso-N-acetylpenicillamide. Similar results were seen with cartilage slices in organ culture. The autocrine increase in CM TGFbeta1 levels following prior exposure to TGFbeta1 was also blocked by NO. CONCLUSION: NO can modulate proteoglycan synthesis indirectly by decreasing the production of TGFbeta1 by chondrocytes exposed to IL-1beta. It prevents autocrine-stimulated increases in TGFbeta1, thus potentially diminishing the anabolic effects of this cytokine in chondrocytes.  (+info)

Expression of both P1 and P2 purine receptor genes by human articular chondrocytes and profile of ligand-mediated prostaglandin E2 release. (3/3820)

OBJECTIVE: To assess the expression and function of purine receptors in articular chondrocytes. METHODS: Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to screen human chondrocyte RNA for expression of P1 and P2 purine receptor subtypes. Purine-stimulated prostaglandin E2 (PGE2) release from chondrocytes, untreated or treated with recombinant human interleukin-1alpha (rHuIL-1alpha), was assessed by radioimmunoassay. RESULTS: RT-PCR demonstrated that human articular chondrocytes transcribe messenger RNA for the P1 receptor subtypes A2a and A2b and the P2 receptor subtype P2Y2, but not for the P1 receptor subtypes A1 and A3. The P1 receptor agonists adenosine and 5'-N-ethylcarboxamidoadenosine did not change PGE2 release from chondrocytes. The P2Y2 agonists ATP and UTP stimulated a small release of PGE2 that was potentiated after pretreatment with rHuIL-1alpha. PGE2 release in response to ATP and UTP cotreatment was not additive, but release in response to coaddition of ATP and bradykinin (BK) or UTP and BK was additive, consistent with ATP and UTP competition for the same receptor site. The potentiation of PGE2 release in response to ATP and UTP after rHuIL-1alpha pretreatment was mimicked by phorbol myristate acetate. CONCLUSION: Human chondrocytes express both P1 and P2 purine receptor subtypes. The function of the P1 receptor subtype is not yet known, but stimulation of the P2Y2 receptor increases IL-1-mediated PGE2 release.  (+info)

Molecular cloning of mouse and bovine chondromodulin-II cDNAs and the growth-promoting actions of bovine recombinant protein. (4/3820)

We previously determined the complete primary sequence of a heparin-binding growth-promoting factor, chondromodulin-II (ChM-II), which stimulated the growth of chondrocytes and osteoblasts in culture. Bovine ChM-II was a 16-kDa basic protein with 133 amino acid residues and exhibited a significant sequence similarity to the repeats of the chicken mim-1 gene product. Here we report the nucleotide sequences of bovine and mouse ChM-II cDNAs. The cDNAs each contained an open-reading frame corresponding to the ChM-II precursor with 151 amino acid residues. The N-terminus of the precursor included a secretory signal sequence of 18 amino acids prior to the mature ChM-II sequence. Unlike MIM-1, there was no repeat structure in the precursor protein, indicating that ChM-II was encoded as a gene product distinct from MIM-1. We then expressed recombinant bovine ChM-II protein which was purified to homogeneity. The recombinant protein stimulated the growth of rabbit growth plate chondrocytes, mouse MC3T3-E1 cells and rat UMR-106 osteoblastic cells in vitro.  (+info)

Gene transfer of cytokine inhibitors into human synovial fibroblasts in the SCID mouse model. (5/3820)

OBJECTIVE: To investigate the effects of retrovirus-based gene delivery of inhibitory cytokines and cytokine inhibitors into human synovial fibroblasts in the SCID mouse model of rheumatoid arthritis (RA). METHODS: The MFG vector was used for gene delivery of tumor necrosis factor alpha receptor (TNFalphaR) p55, viral interleukin-10 (IL-10), and murine IL-10 into RA synovial fibroblasts. The effect on invasion of these cells into human articular cartilage and on perichondrocytic cartilage degradation was examined after 60 days of coimplantation into the SCID mouse. RESULTS: TNFalphaR p55 gene transfer showed only a limited effect on inhibition of RA synovial fibroblast invasiveness and cartilage degradation. In contrast, invasion of the RA synovial fibroblasts into the coimplanted cartilage was strongly inhibited by both viral and murine IL-10. Perichondrocytic cartilage degradation was not affected by either form of IL-10. CONCLUSION: The data show that cytokines can be successfully inserted into the genome of human RA synovial fibroblasts using a retroviral vector delivery system, and that the SCID mouse model of human RA is a valuable tool for examining the effects of gene transfer. In addition, inhibition of more than one cytokine pathway may be required to inhibit both synovial- and chondrocyte-mediated cartilage destruction in RA.  (+info)

Transduction mechanisms of porcine chondrocyte inorganic pyrophosphate elaboration. (6/3820)

OBJECTIVE: To investigate cellular signaling mechanisms that influence chondrocyte production of inorganic pyrophosphate (PPi), which promotes calcium pyrophosphate dihydrate (CPPD) crystal deposition. METHODS: Articular chondrocyte and cartilage cultures were stimulated with protein kinase C (PKC) activator and adenyl cyclase activator. Generation of extracellular PPi was measured. RESULTS: Adenyl cyclase activation resulted in diminished pyrophosphate generation. PKC activation stimulated pyrophosphate elaboration. CONCLUSION: Two signaling pathways, cAMP and PKC, modulate generation of extracellular pyrophosphate by cartilage and chondrocytes. They are novel targets for potentially diminishing extracellular pyrophosphate elaboration that leads to CPPD crystal deposition.  (+info)

COL9A3: A third locus for multiple epiphyseal dysplasia. (7/3820)

Multiple epiphyseal dysplasia (MED), an autosomal dominant osteochondrodysplasia, is a clinically and genetically heterogeneous disorder characterized by mild short stature and early-onset osteoarthritis. The phenotypic spectrum includes the mild Ribbing type, the more severe Fairbank type, and some unclassified forms. Linkage studies have identified two loci for MED. One of these, EDM1, is on chromosome 19, in a region that contains the cartilage oligomeric matrix protein (COMP) gene. Mutations have been identified in this gene in patients with the Ribbing type, the Fairbank type, and unclassified forms of MED. The second locus, EDM2, maps to chromosome 1, in a region spanning COL9A2. Recently, a splice-site mutation was found in COL9A2, causing skipping of exon 3 in one family with MED. Because of the exclusion of the EDM1 and EDM2 loci in some families, the existence of a third locus has been postulated. We report here one family with MED, evaluated clinically and radiologically and tested for linkage with candidate genes, including COMP, COL9A1, COL9A2, and COL9A3. No linkage was found with COMP, COL9A1, or COL9A2, but an inheritance pattern consistent with linkage was observed with COL9A3. Mutation analysis of COL9A3 identified an A-->T transversion in the acceptor splice site of intron 2 in affected family members. The mutation led to skipping of exon 3 and an in-frame deletion of 12 amino acid residues in the COL3 domain of the alpha3(IX) chain and thus appeared to be similar to that reported for COL9A2. This is the first disease-causing mutation identified in COL9A3. Our results also show that COL9A3, located on chromosome 20, is a third locus for MED.  (+info)

Multilineage potential of adult human mesenchymal stem cells. (8/3820)

Human mesenchymal stem cells are thought to be multipotent cells, which are present in adult marrow, that can replicate as undifferentiated cells and that have the potential to differentiate to lineages of mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma. Cells that have the characteristics of human mesenchymal stem cells were isolated from marrow aspirates of volunteer donors. These cells displayed a stable phenotype and remained as a monolayer in vitro. These adult stem cells could be induced to differentiate exclusively into the adipocytic, chondrocytic, or osteocytic lineages. Individual stem cells were identified that, when expanded to colonies, retained their multilineage potential.  (+info)

Chondrocytes are the specialized cells that produce and maintain the extracellular matrix of cartilage tissue. They are responsible for synthesizing and secreting the collagen fibers, proteoglycans, and other components that give cartilage its unique properties, such as elasticity, resiliency, and resistance to compression. Chondrocytes are located within lacunae, or small cavities, in the cartilage matrix, and they receive nutrients and oxygen through diffusion from the surrounding tissue fluid. They are capable of adapting to changes in mechanical stress by modulating the production and organization of the extracellular matrix, which allows cartilage to withstand various loads and maintain its structural integrity. Chondrocytes play a crucial role in the development, maintenance, and repair of cartilaginous tissues throughout the body, including articular cartilage, costal cartilage, and growth plate cartilage.

Articular cartilage is the smooth, white tissue that covers the ends of bones where they come together to form joints. It provides a cushion between bones and allows for smooth movement by reducing friction. Articular cartilage also absorbs shock and distributes loads evenly across the joint, protecting the bones from damage. It is avascular, meaning it does not have its own blood supply, and relies on the surrounding synovial fluid for nutrients. Over time, articular cartilage can wear down or become damaged due to injury or disease, leading to conditions such as osteoarthritis.

Cartilage is a type of connective tissue that is found throughout the body in various forms. It is made up of specialized cells called chondrocytes, which are embedded in a firm, flexible matrix composed of collagen fibers and proteoglycans. This unique structure gives cartilage its characteristic properties of being both strong and flexible.

There are three main types of cartilage in the human body: hyaline cartilage, elastic cartilage, and fibrocartilage.

1. Hyaline cartilage is the most common type and is found in areas such as the articular surfaces of bones (where they meet to form joints), the nose, trachea, and larynx. It has a smooth, glassy appearance and provides a smooth, lubricated surface for joint movement.
2. Elastic cartilage contains more elastin fibers than hyaline cartilage, which gives it greater flexibility and resilience. It is found in structures such as the external ear and parts of the larynx and epiglottis.
3. Fibrocartilage has a higher proportion of collagen fibers and fewer chondrocytes than hyaline or elastic cartilage. It is found in areas that require high tensile strength, such as the intervertebral discs, menisci (found in joints like the knee), and the pubic symphysis.

Cartilage plays a crucial role in supporting and protecting various structures within the body, allowing for smooth movement and providing a cushion between bones to absorb shock and prevent wear and tear. However, cartilage has limited capacity for self-repair and regeneration, making damage or degeneration of cartilage tissue a significant concern in conditions such as osteoarthritis.

A growth plate, also known as an epiphyseal plate or physis, is a layer of cartilaginous tissue found near the ends of long bones in children and adolescents. This region is responsible for the longitudinal growth of bones during development. The growth plate contains actively dividing cells that differentiate into chondrocytes, which produce and deposit new matrix, leading to bone elongation. Once growth is complete, usually in late adolescence or early adulthood, the growth plates ossify (harden) and are replaced by solid bone, transforming into the epiphyseal line.

Osteoarthritis (OA) is a type of joint disease that is characterized by the breakdown and eventual loss of cartilage - the tissue that cushions the ends of bones where they meet in the joints. This breakdown can cause the bones to rub against each other, causing pain, stiffness, and loss of mobility. OA can occur in any joint, but it most commonly affects the hands, knees, hips, and spine. It is often associated with aging and can be caused or worsened by obesity, injury, or overuse.

The medical definition of osteoarthritis is: "a degenerative, non-inflammatory joint disease characterized by the loss of articular cartilage, bone remodeling, and the formation of osteophytes (bone spurs). It is often associated with pain, stiffness, and decreased range of motion in the affected joint."

Collagen Type II is a specific type of collagen that is a major component of the extracellular matrix in articular cartilage, which is the connective tissue that covers and protects the ends of bones in joints. It is also found in other tissues such as the vitreous humor of the eye and the inner ear.

Collagen Type II is a triple helix molecule composed of three polypeptide chains that contain a high proportion of the amino acids proline and hydroxyproline. This type of collagen provides structural support and elasticity to tissues, and it also plays a role in the regulation of cell behavior and signaling.

Collagen Type II is a target for autoimmune responses in conditions such as rheumatoid arthritis, where the immune system mistakenly attacks the body's own collagen, leading to joint inflammation and damage. It is also a common component of various dietary supplements and therapies used to support joint health and treat osteoarthritis.

Medical Definition:

Matrix Metalloproteinase 13 (MMP-13), also known as collagenase 3, is an enzyme belonging to the family of Matrix Metalloproteinases. These enzymes are involved in the degradation of extracellular matrix components, playing crucial roles in various physiological and pathological processes such as tissue remodeling, wound healing, and cancer progression.

MMP-13 has a specific affinity for cleaving type II collagen, one of the major structural proteins found in articular cartilage. It is also capable of degrading other extracellular matrix components like proteoglycans, elastin, and gelatin. This enzyme is primarily produced by chondrocytes, synovial fibroblasts, and osteoblasts.

Increased expression and activity of MMP-13 have been implicated in the pathogenesis of several diseases, most notably osteoarthritis (OA) and cancer. In OA, overexpression of MMP-13 leads to excessive degradation of articular cartilage, contributing to joint damage and degeneration. In cancer, MMP-13 facilitates tumor cell invasion and metastasis by breaking down the surrounding extracellular matrix.

Regulation of MMP-13 activity is essential for maintaining tissue homeostasis and preventing disease progression. Various therapeutic strategies aiming to inhibit MMP-13 activity are being explored as potential treatments for osteoarthritis and cancer.

Aggrecan is a large, complex proteoglycan molecule found in the extracellular matrix of articular cartilage and other connective tissues. It is a key component of the structural framework of these tissues, helping to provide resiliency, cushioning, and protection to the cells within. Aggrecan contains numerous glycosaminoglycan (GAG) chains, which are negatively charged molecules that attract water and ions, creating a swelling pressure that contributes to the tissue's load-bearing capacity.

The medical definition of 'Aggrecans' can be described as:

1. A large proteoglycan molecule found in articular cartilage and other connective tissues.
2. Composed of a core protein with attached glycosaminoglycan (GAG) chains, primarily chondroitin sulfate and keratan sulfate.
3. Plays a crucial role in the biomechanical properties of articular cartilage by attracting water and ions, creating a swelling pressure that contributes to the tissue's load-bearing capacity.
4. Aggrecan degradation or loss is associated with various joint diseases, such as osteoarthritis, due to reduced structural integrity and shock-absorbing capabilities of articular cartilage.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Chondrogenesis is the process of cartilage formation during embryonic development and in the healing of certain types of injuries. It involves the differentiation of mesenchymal stem cells into chondrocytes, which are the specialized cells that produce and maintain the extracellular matrix of cartilage.

During chondrogenesis, the mesenchymal stem cells condense and form a template for the future cartilaginous tissue. These cells then differentiate into chondrocytes, which begin to produce and deposit collagen type II, proteoglycans, and other extracellular matrix components that give cartilage its unique biochemical and mechanical properties.

Chondrogenesis is a critical process for the development of various structures in the body, including the skeletal system, where it plays a role in the formation of articular cartilage, growth plates, and other types of cartilage. Understanding the molecular mechanisms that regulate chondrogenesis is important for developing therapies to treat cartilage injuries and degenerative diseases such as osteoarthritis.

Proteoglycans are complex, highly negatively charged macromolecules that are composed of a core protein covalently linked to one or more glycosaminoglycan (GAG) chains. They are a major component of the extracellular matrix (ECM) and play crucial roles in various biological processes, including cell signaling, regulation of growth factor activity, and maintenance of tissue structure and function.

The GAG chains, which can vary in length and composition, are long, unbranched polysaccharides that are composed of repeating disaccharide units containing a hexuronic acid (either glucuronic or iduronic acid) and a hexosamine (either N-acetylglucosamine or N-acetylgalactosamine). These GAG chains can be sulfated to varying degrees, which contributes to the negative charge of proteoglycans.

Proteoglycans are classified into four major groups based on their core protein structure and GAG composition: heparan sulfate/heparin proteoglycans, chondroitin/dermatan sulfate proteoglycans, keratan sulfate proteoglycans, and hyaluronan-binding proteoglycans. Each group has distinct functions and is found in specific tissues and cell types.

In summary, proteoglycans are complex macromolecules composed of a core protein and one or more GAG chains that play important roles in the ECM and various biological processes, including cell signaling, growth factor regulation, and tissue structure maintenance.

Collagen type X is a specific type of collagen that is primarily found in the hypertrophic zone of mature cartilage, which is located near the site of bone formation during endochondral ossification. It plays a crucial role in the mineralization process of the cartilage matrix and is essential for the formation of healthy bones. Collagen type X is composed of three identical alpha chains that form a triple helix structure, and it is synthesized by chondrocytes, which are the specialized cells found in cartilage tissue. Mutations in the gene that encodes collagen type X have been associated with certain skeletal disorders, such as Schmid metaphyseal chondrodysplasia.

SOX9 (SRY-related HMG-box gene 9) is a transcription factor that belongs to the SOX family of proteins, which are characterized by a high mobility group (HMG) box DNA-binding domain. SOX9 plays crucial roles in various developmental processes, including sex determination, chondrogenesis, and neurogenesis.

As a transcription factor, SOX9 binds to specific DNA sequences in the promoter or enhancer regions of its target genes and regulates their expression. In the context of sex determination, SOX9 is essential for the development of Sertoli cells in the male gonad, which are responsible for supporting sperm production. SOX9 also plays a role in maintaining the undifferentiated state of stem cells and promoting cell differentiation in various tissues.

Mutations in the SOX9 gene have been associated with several human genetic disorders, including campomelic dysplasia, a severe skeletal disorder characterized by bowed legs, and sex reversal in individuals with XY chromosomes.

Extracellular matrix (ECM) proteins are a group of structural and functional molecules that provide support, organization, and regulation to the cells in tissues and organs. The ECM is composed of a complex network of proteins, glycoproteins, and carbohydrates that are secreted by the cells and deposited outside of them.

ECM proteins can be classified into several categories based on their structure and function, including:

1. Collagens: These are the most abundant ECM proteins and provide strength and stability to tissues. They form fibrils that can withstand high tensile forces.
2. Proteoglycans: These are complex molecules made up of a core protein and one or more glycosaminoglycan (GAG) chains. The GAG chains attract water, making proteoglycans important for maintaining tissue hydration and resilience.
3. Elastin: This is an elastic protein that allows tissues to stretch and recoil, such as in the lungs and blood vessels.
4. Fibronectins: These are large glycoproteins that bind to cells and ECM components, providing adhesion, migration, and signaling functions.
5. Laminins: These are large proteins found in basement membranes, which provide structural support for epithelial and endothelial cells.
6. Tenascins: These are large glycoproteins that modulate cell adhesion and migration, and regulate ECM assembly and remodeling.

Together, these ECM proteins create a microenvironment that influences cell behavior, differentiation, and function. Dysregulation of ECM proteins has been implicated in various diseases, including fibrosis, cancer, and degenerative disorders.

Glycosaminoglycans (GAGs) are long, unbranched polysaccharides composed of repeating disaccharide units. They are a major component of the extracellular matrix and connective tissues in the body. GAGs are negatively charged due to the presence of sulfate and carboxyl groups, which allows them to attract positively charged ions and water molecules, contributing to their ability to retain moisture and maintain tissue hydration and elasticity.

GAGs can be categorized into four main groups: heparin/heparan sulfate, chondroitin sulfate/dermatan sulfate, keratan sulfate, and hyaluronic acid. These different types of GAGs have varying structures and functions in the body, including roles in cell signaling, inflammation, and protection against enzymatic degradation.

Heparin is a highly sulfated form of heparan sulfate that is found in mast cells and has anticoagulant properties. Chondroitin sulfate and dermatan sulfate are commonly found in cartilage and contribute to its resiliency and ability to withstand compressive forces. Keratan sulfate is found in corneas, cartilage, and bone, where it plays a role in maintaining the structure and function of these tissues. Hyaluronic acid is a large, nonsulfated GAG that is widely distributed throughout the body, including in synovial fluid, where it provides lubrication and shock absorption for joints.

Chondrosarcoma is a type of cancer that develops in the cartilaginous tissue, which is the flexible and smooth connective tissue found in various parts of the body such as the bones, ribs, and nose. It is characterized by the production of malignant cartilage cells that can invade surrounding tissues and spread to other parts of the body (metastasis).

Chondrosarcomas are typically slow-growing tumors but can be aggressive in some cases. They usually occur in adults over the age of 40, and men are more commonly affected than women. The most common sites for chondrosarcoma development include the bones of the pelvis, legs, and arms.

Treatment for chondrosarcoma typically involves surgical removal of the tumor, along with radiation therapy or chemotherapy in some cases. The prognosis for chondrosarcoma depends on several factors, including the size and location of the tumor, the grade of malignancy, and whether it has spread to other parts of the body.

Collagen is the most abundant protein in the human body, and it is a major component of connective tissues such as tendons, ligaments, skin, and bones. Collagen provides structure and strength to these tissues and helps them to withstand stretching and tension. It is made up of long chains of amino acids, primarily glycine, proline, and hydroxyproline, which are arranged in a triple helix structure. There are at least 16 different types of collagen found in the body, each with slightly different structures and functions. Collagen is important for maintaining the integrity and health of tissues throughout the body, and it has been studied for its potential therapeutic uses in various medical conditions.

Bone development, also known as ossification, is the process by which bone tissue is formed and grows. This complex process involves several different types of cells, including osteoblasts, which produce new bone matrix, and osteoclasts, which break down and resorb existing bone tissue.

There are two main types of bone development: intramembranous and endochondral ossification. Intramembranous ossification occurs when bone tissue forms directly from connective tissue, while endochondral ossification involves the formation of a cartilage model that is later replaced by bone.

During fetal development, most bones develop through endochondral ossification, starting as a cartilage template that is gradually replaced by bone tissue. However, some bones, such as those in the skull and clavicles, develop through intramembranous ossification.

Bone development continues after birth, with new bone tissue being laid down and existing tissue being remodeled throughout life. This ongoing process helps to maintain the strength and integrity of the skeleton, allowing it to adapt to changing mechanical forces and repair any damage that may occur.

Cell differentiation is the process by which a less specialized cell, or stem cell, becomes a more specialized cell type with specific functions and structures. This process involves changes in gene expression, which are regulated by various intracellular signaling pathways and transcription factors. Differentiation results in the development of distinct cell types that make up tissues and organs in multicellular organisms. It is a crucial aspect of embryonic development, tissue repair, and maintenance of homeostasis in the body.

The extracellular matrix (ECM) is a complex network of biomolecules that provides structural and biochemical support to cells in tissues and organs. It is composed of various proteins, glycoproteins, and polysaccharides, such as collagens, elastin, fibronectin, laminin, and proteoglycans. The ECM plays crucial roles in maintaining tissue architecture, regulating cell behavior, and facilitating communication between cells. It provides a scaffold for cell attachment, migration, and differentiation, and helps to maintain the structural integrity of tissues by resisting mechanical stresses. Additionally, the ECM contains various growth factors, cytokines, and chemokines that can influence cellular processes such as proliferation, survival, and differentiation. Overall, the extracellular matrix is essential for the normal functioning of tissues and organs, and its dysregulation can contribute to various pathological conditions, including fibrosis, cancer, and degenerative diseases.

Osteoarthritis (OA) of the knee is a degenerative joint disease that affects the articular cartilage and subchondral bone in the knee joint. It is characterized by the breakdown and eventual loss of the smooth, cushioning cartilage that covers the ends of bones and allows for easy movement within joints. As the cartilage wears away, the bones rub against each other, causing pain, stiffness, and limited mobility. Osteoarthritis of the knee can also lead to the formation of bone spurs (osteophytes) and cysts in the joint. This condition is most commonly found in older adults, but it can also occur in younger people as a result of injury or overuse. Risk factors include obesity, family history, previous joint injuries, and repetitive stress on the knee joint. Treatment options typically include pain management, physical therapy, and in some cases, surgery.

Cartilage diseases refer to conditions that affect the cartilaginous tissues in the body. Cartilage is a firm, flexible connective tissue found in many areas of the body, including the joints, ribcage, ears, and nose. It provides structure and support, allows for smooth movement between bones, and protects the ends of bones from friction.

There are several types of cartilage diseases, including:

1. Osteoarthritis (OA): This is a degenerative joint disease that occurs when the protective cartilage that cushions the ends of your bones wears down over time. It can cause pain, stiffness, and loss of mobility in the affected joints.
2. Rheumatoid arthritis (RA): This is an autoimmune disorder that causes inflammation in the lining of the joints, leading to cartilage damage and bone erosion.
3. Traumatic arthritis: This occurs when a joint is injured, causing damage to the cartilage and resulting in pain, stiffness, and loss of mobility.
4. Infectious arthritis: This occurs when a joint becomes infected, leading to inflammation and potential damage to the cartilage.
5. Chondromalacia patellae: This is a condition that affects the cartilage on the back of the kneecap, causing pain and stiffness in the knee.
6. Costochondritis: This is an inflammation of the cartilage in the ribcage, causing chest pain and discomfort.
7. Nasal septal deviation: This is a condition where the cartilage that separates the nostrils is crooked or off-center, causing difficulty breathing through the nose.
8. Osteochondritis dissecans (OCD): This is a joint condition that occurs when a piece of cartilage and bone in a joint becomes detached, causing pain and stiffness.
9. Synovial chondromatosis: This is a rare condition where nodules made up of cartilage form in the lining of a joint, causing pain, swelling, and limited mobility.

Treatment for cartilage diseases varies depending on the specific condition and severity, but may include medication, physical therapy, surgery, or a combination of these.

Matrix metalloproteinase 3 (MMP-3), also known as stromelysin-1, is a member of the matrix metalloproteinase family. These are a group of enzymes involved in the degradation of the extracellular matrix, the network of proteins and other molecules that provides structural and biochemical support to surrounding cells. MMP-3 is secreted by various cell types, including fibroblasts, synovial cells, and chondrocytes, in response to inflammatory cytokines.

MMP-3 has the ability to degrade several extracellular matrix components, such as proteoglycans, laminin, fibronectin, and various types of collagen. It also plays a role in processing and activating other MMPs, thereby contributing to the overall breakdown of the extracellular matrix. This activity is crucial during processes like tissue remodeling, wound healing, and embryonic development; however, uncontrolled or excessive MMP-3 activation can lead to pathological conditions, including arthritis, cancer, and cardiovascular diseases.

In summary, Matrix metalloproteinase 3 (MMP-3) is a proteolytic enzyme involved in the degradation of the extracellular matrix and the activation of other MMPs. Its dysregulation has been implicated in several diseases.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

Interleukin-1 beta (IL-1β) is a member of the interleukin-1 cytokine family and is primarily produced by activated macrophages in response to inflammatory stimuli. It is a crucial mediator of the innate immune response and plays a key role in the regulation of various biological processes, including cell proliferation, differentiation, and apoptosis. IL-1β is involved in the pathogenesis of several inflammatory diseases, such as rheumatoid arthritis, inflammatory bowel disease, and atherosclerosis. It exerts its effects by binding to the interleukin-1 receptor, which triggers a signaling cascade that leads to the activation of various transcription factors and the expression of target genes.

A chick embryo refers to the developing organism that arises from a fertilized chicken egg. It is often used as a model system in biological research, particularly during the stages of development when many of its organs and systems are forming and can be easily observed and manipulated. The study of chick embryos has contributed significantly to our understanding of various aspects of developmental biology, including gastrulation, neurulation, organogenesis, and pattern formation. Researchers may use various techniques to observe and manipulate the chick embryo, such as surgical alterations, cell labeling, and exposure to drugs or other agents.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

Interleukin-1 (IL-1) is a type of cytokine, which are proteins that play a crucial role in cell signaling. Specifically, IL-1 is a pro-inflammatory cytokine that is involved in the regulation of immune and inflammatory responses in the body. It is produced by various cells, including monocytes, macrophages, and dendritic cells, in response to infection or injury.

IL-1 exists in two forms, IL-1α and IL-1β, which have similar biological activities but are encoded by different genes. Both forms of IL-1 bind to the same receptor, IL-1R, and activate intracellular signaling pathways that lead to the production of other cytokines, chemokines, and inflammatory mediators.

IL-1 has a wide range of biological effects, including fever induction, activation of immune cells, regulation of hematopoiesis (the formation of blood cells), and modulation of bone metabolism. Dysregulation of IL-1 production or activity has been implicated in various inflammatory diseases, such as rheumatoid arthritis, gout, and inflammatory bowel disease. Therefore, IL-1 is an important target for the development of therapies aimed at modulating the immune response and reducing inflammation.

Tissue engineering is a branch of biomedical engineering that combines the principles of engineering, materials science, and biological sciences to develop functional substitutes for damaged or diseased tissues and organs. It involves the creation of living, three-dimensional structures that can restore, maintain, or improve tissue function. This is typically accomplished through the use of cells, scaffolds (biodegradable matrices), and biologically active molecules. The goal of tissue engineering is to develop biological substitutes that can ultimately restore normal function and structure in damaged tissues or organs.

Alginates are a type of polysaccharide derived from brown algae or produced synthetically, which have gelling and thickening properties. In medical context, they are commonly used as a component in wound dressings, dental impressions, and bowel cleansing products. The gels formed by alginates can provide a protective barrier to wounds, help maintain a moist environment, and promote healing. They can also be used to create a mold of the mouth or other body parts in dental and medical applications. In bowel cleansing, sodium alginates are often combined with sodium bicarbonate and water to form a solution that expands and stimulates bowel movements, helping to prepare the colon for procedures such as colonoscopy.

Collagenases are a group of enzymes that have the ability to break down collagen, which is a structural protein found in connective tissues such as tendons, ligaments, and skin. Collagen is an important component of the extracellular matrix, providing strength and support to tissues throughout the body.

Collagenases are produced by various organisms, including bacteria, animals, and humans. In humans, collagenases play a crucial role in normal tissue remodeling and repair processes, such as wound healing and bone resorption. However, excessive or uncontrolled activity of collagenases can contribute to the development of various diseases, including arthritis, periodontitis, and cancer metastasis.

Bacterial collagenases are often used in research and medical applications for their ability to digest collagen quickly and efficiently. For example, they may be used to study the structure and function of collagen or to isolate cells from tissues. However, the clinical use of bacterial collagenases is limited due to concerns about their potential to cause tissue damage and inflammation.

Overall, collagenases are important enzymes that play a critical role in maintaining the health and integrity of connective tissues throughout the body.

Hyaluronic acid is a glycosaminoglycan, a type of complex carbohydrate, that is naturally found in the human body. It is most abundant in the extracellular matrix of soft connective tissues, including the skin, eyes, and joints. Hyaluronic acid is known for its remarkable capacity to retain water, which helps maintain tissue hydration, lubrication, and elasticity. Its functions include providing structural support, promoting wound healing, and regulating cell growth and differentiation. In the medical field, hyaluronic acid is often used in various forms as a therapeutic agent for conditions like osteoarthritis, dry eye syndrome, and skin rejuvenation.

Osteogenesis is the process of bone formation or development. It involves the differentiation and maturation of osteoblasts, which are bone-forming cells that synthesize and deposit the organic matrix of bone tissue, composed mainly of type I collagen. This organic matrix later mineralizes to form the inorganic crystalline component of bone, primarily hydroxyapatite.

There are two primary types of osteogenesis: intramembranous and endochondral. Intramembranous osteogenesis occurs directly within connective tissue, where mesenchymal stem cells differentiate into osteoblasts and form bone tissue without an intervening cartilage template. This process is responsible for the formation of flat bones like the skull and clavicles.

Endochondral osteogenesis, on the other hand, involves the initial development of a cartilaginous model or template, which is later replaced by bone tissue. This process forms long bones, such as those in the limbs, and occurs through several stages involving chondrocyte proliferation, hypertrophy, and calcification, followed by invasion of blood vessels and osteoblasts to replace the cartilage with bone tissue.

Abnormalities in osteogenesis can lead to various skeletal disorders and diseases, such as osteogenesis imperfecta (brittle bone disease), achondroplasia (a form of dwarfism), and cleidocranial dysplasia (a disorder affecting skull and collarbone development).

Ear cartilage, also known as auricular cartilage, refers to the flexible connective tissue that makes up the structural framework of the external ear or pinna. The ear cartilage provides support and shape to the ear, helping to direct sound waves into the ear canal and towards the eardrum.

The ear cartilage is composed of type II collagen fibers and proteoglycans, which give it its flexibility and resiliency. It is covered by a thin layer of skin on both sides and contains no bones. Instead, the ear cartilage is shaped and maintained by the surrounding muscles and connective tissue.

There are three main parts of the ear cartilage: the helix, the antihelix, and the tragus. The helix is the outer rim of the ear, while the antihelix is the curved ridge that runs parallel to the helix. The tragus is the small piece of cartilage that projects from the front of the ear canal.

Ear cartilage can be affected by various conditions, including trauma, infection, and degenerative changes associated with aging. In some cases, surgical procedures may be required to reshape or reconstruct damaged ear cartilage.

Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a laboratory technique used in molecular biology to amplify and detect specific DNA sequences. This technique is particularly useful for the detection and quantification of RNA viruses, as well as for the analysis of gene expression.

The process involves two main steps: reverse transcription and polymerase chain reaction (PCR). In the first step, reverse transcriptase enzyme is used to convert RNA into complementary DNA (cDNA) by reading the template provided by the RNA molecule. This cDNA then serves as a template for the PCR amplification step.

In the second step, the PCR reaction uses two primers that flank the target DNA sequence and a thermostable polymerase enzyme to repeatedly copy the targeted cDNA sequence. The reaction mixture is heated and cooled in cycles, allowing the primers to anneal to the template, and the polymerase to extend the new strand. This results in exponential amplification of the target DNA sequence, making it possible to detect even small amounts of RNA or cDNA.

RT-PCR is a sensitive and specific technique that has many applications in medical research and diagnostics, including the detection of viruses such as HIV, hepatitis C virus, and SARS-CoV-2 (the virus that causes COVID-19). It can also be used to study gene expression, identify genetic mutations, and diagnose genetic disorders.

Osteochondrodysplasias are a group of genetic disorders that affect the development of bones and cartilage. These conditions can result in dwarfism or short stature, as well as other skeletal abnormalities. Osteochondrodysplasias can be caused by mutations in genes that regulate bone and cartilage growth, and they are often characterized by abnormalities in the shape, size, and/or structure of the bones and cartilage.

There are many different types of osteochondrodysplasias, each with its own specific symptoms and patterns of inheritance. Some common examples include achondroplasia, thanatophoric dysplasia, and spondyloepiphyseal dysplasia. These conditions can vary in severity, and some may be associated with other health problems, such as respiratory difficulties or neurological issues.

Treatment for osteochondrodysplasias typically focuses on managing the symptoms and addressing any related health concerns. This may involve physical therapy, bracing or surgery to correct skeletal abnormalities, and treatment for any associated medical conditions. In some cases, genetic counseling may also be recommended for individuals with osteochondrodysplasias and their families.

Hypertrophy, in the context of physiology and pathology, refers to an increase in the size of an organ or tissue due to an enlargement of its constituent cells. It is often used to describe the growth of muscle cells (myocytes) in response to increased workload or hormonal stimulation, resulting in an increase in muscle mass. However, hypertrophy can also occur in other organs such as the heart (cardiac hypertrophy) in response to high blood pressure or valvular heart disease.

It is important to note that while hypertrophy involves an increase in cell size, hyperplasia refers to an increase in cell number. In some cases, both hypertrophy and hyperplasia can occur together, leading to a significant increase in the overall size and function of the organ or tissue.

The metatarsal bones are a group of five long bones in the foot that connect the tarsal bones in the hindfoot to the phalanges in the forefoot. They are located between the tarsal and phalangeal bones and are responsible for forming the arch of the foot and transmitting weight-bearing forces during walking and running. The metatarsal bones are numbered 1 to 5, with the first metatarsal being the shortest and thickest, and the fifth metatarsal being the longest and thinnest. Each metatarsal bone has a base, shaft, and head, and they articulate with each other and with the surrounding bones through joints. Any injury or disorder affecting the metatarsal bones can cause pain and difficulty in walking or standing.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

Gene expression is the process by which the information encoded in a gene is used to synthesize a functional gene product, such as a protein or RNA molecule. This process involves several steps: transcription, RNA processing, and translation. During transcription, the genetic information in DNA is copied into a complementary RNA molecule, known as messenger RNA (mRNA). The mRNA then undergoes RNA processing, which includes adding a cap and tail to the mRNA and splicing out non-coding regions called introns. The resulting mature mRNA is then translated into a protein on ribosomes in the cytoplasm through the process of translation.

The regulation of gene expression is a complex and highly controlled process that allows cells to respond to changes in their environment, such as growth factors, hormones, and stress signals. This regulation can occur at various stages of gene expression, including transcriptional activation or repression, RNA processing, mRNA stability, and translation. Dysregulation of gene expression has been implicated in many diseases, including cancer, genetic disorders, and neurological conditions.

The term "stifle" is commonly used in veterinary medicine to refer to the joint in the leg of animals, specifically the knee joint in quadrupeds such as dogs and horses. In human anatomy, this joint is called the patellofemoral joint or knee joint. The stifle is a complex joint made up of several bones, including the femur, tibia, and patella (kneecap), as well as various ligaments, tendons, and cartilage that provide stability and support. Injuries or diseases affecting the stifle can cause lameness, pain, and decreased mobility in animals.

Matrilin proteins are a group of extracellular matrix (ECM) proteins that are predominantly found in cartilaginous tissues, such as articular cartilage, costal cartilage, and intervertebral discs. They belong to the von Willebrand factor A (vWF-A) domain-containing protein family and play important roles in maintaining the structural integrity and organization of the ECM.

Matrilin proteins are composed of multiple domains, including vWF-A domains, coiled-coil domains, and calcium-binding epidermal growth factor (cbEGF)-like domains. They can form multimeric complexes through their coiled-coil domains, which helps to stabilize the ECM network.

There are four known matrilin proteins in humans, designated as Matrilin-1, Matrilin-2, Matrilin-3, and Matrilin-4. Each of these proteins has distinct tissue distribution patterns and functions. For example, Matrilin-1 is primarily found in hyaline cartilage and is involved in regulating chondrocyte differentiation and matrix assembly. Matrilin-2 is widely expressed in various tissues, including cartilage, tendon, and ligament, and plays a role in maintaining the organization of collagen fibrils. Matrilin-3 is specifically expressed in articular cartilage and is involved in regulating the formation and maintenance of the cartilaginous matrix. Matrilin-4 is found in both hyaline and fibrocartilage, as well as in tendons and ligaments, and has been implicated in regulating collagen fibrillogenesis and tissue development.

Mutations in matrilin genes have been associated with various musculoskeletal disorders, such as multiple epiphyseal dysplasia (MED) and spondyloepimetaphyseal dysplasia (SEMD). These genetic defects can lead to abnormalities in the structure and organization of the ECM, resulting in joint pain, stiffness, and reduced mobility.

Glucuronic acid is a physiological important organic acid, which is a derivative of glucose. It is formed by the oxidation of the primary alcohol group of glucose to form a carboxyl group at the sixth position. Glucuronic acid plays a crucial role in the detoxification process in the body as it conjugates with toxic substances, making them water-soluble and facilitating their excretion through urine or bile. This process is known as glucuronidation. It is also a component of various polysaccharides, such as heparan sulfate and chondroitin sulfate, which are found in the extracellular matrix of connective tissues.

Procollagen N-Endopeptidase, also known as ADAMTS2 (A Disintegrin And Metalloproteinase with Thrombospondin type 1 motif, member 2), is an enzyme involved in the processing and maturation of procollagens. Specifically, it cleaves off the N-terminal extension peptides from procollagen types I, II, and III, allowing for the formation of stable collagen fibrils. Mutations in the ADAMTS2 gene can lead to various connective tissue disorders, such as Ehlers-Danlos syndrome and dermatosparaxis type of cutis laxa.

"Bone" is the hard, dense connective tissue that makes up the skeleton of vertebrate animals. It provides support and protection for the body's internal organs, and serves as a attachment site for muscles, tendons, and ligaments. Bone is composed of cells called osteoblasts and osteoclasts, which are responsible for bone formation and resorption, respectively, and an extracellular matrix made up of collagen fibers and mineral crystals.

Bones can be classified into two main types: compact bone and spongy bone. Compact bone is dense and hard, and makes up the outer layer of all bones and the shafts of long bones. Spongy bone is less dense and contains large spaces, and makes up the ends of long bones and the interior of flat and irregular bones.

The human body has 206 bones in total. They can be further classified into five categories based on their shape: long bones, short bones, flat bones, irregular bones, and sesamoid bones.

Bone Morphogenetic Protein 2 (BMP-2) is a growth factor that belongs to the transforming growth factor-beta (TGF-β) superfamily. It plays a crucial role in bone and cartilage formation, as well as in the regulation of wound healing and embryonic development. BMP-2 stimulates the differentiation of mesenchymal stem cells into osteoblasts, which are cells responsible for bone formation.

BMP-2 has been approved by the US Food and Drug Administration (FDA) as a medical device to promote bone growth in certain spinal fusion surgeries and in the treatment of open fractures that have not healed properly. It is usually administered in the form of a collagen sponge soaked with recombinant human BMP-2 protein, which is a laboratory-produced version of the natural protein.

While BMP-2 has shown promising results in some clinical applications, its use is not without risks and controversies. Some studies have reported adverse effects such as inflammation, ectopic bone formation, and increased rates of cancer, which have raised concerns about its safety and efficacy. Therefore, it is essential to weigh the benefits and risks of BMP-2 therapy on a case-by-case basis and under the guidance of a qualified healthcare professional.

Hexuronic acids are a type of uronic acid that contains six carbon atoms and is commonly found in various biological tissues and polysaccharides, such as pectins, heparin, and certain glycoproteins. The most common hexuronic acids are glucuronic acid and iduronic acid, which are formed from the oxidation of the corresponding hexoses, glucose and galactose, respectively. Hexuronic acids play important roles in various biological processes, including the detoxification and excretion of xenobiotics, the formation of proteoglycans, and the regulation of cell growth and differentiation.

Medical Definition of Matrix Metalloproteinase 1 (MMP-1):

Matrix metalloproteinase 1, also known as collagenase-1 or fibroblast collagenase, is a member of the matrix metalloproteinase family of enzymes. These enzymes are involved in degrading and remodeling extracellular matrix components, such as collagens, gelatins, and other proteins. MMP-1 specifically targets interstitial collagens (types I, II, III, VII, and X) and plays a crucial role in tissue repair, wound healing, and pathological processes like tumor invasion and metastasis. It is secreted as an inactive proenzyme and requires activation before it can carry out its proteolytic functions. MMP-1 activity is regulated at various levels, including transcription, activation, and inhibition by endogenous tissue inhibitors of metalloproteinases (TIMPs). Dysregulation of MMP-1 has been implicated in several diseases, such as arthritis, cancer, and fibrosis.

Collagen type IX is a type of collagen that is found in the extracellular matrix, particularly in the cartilage and vitreous humor of the eye. It is a heterotrimeric protein made up of three alpha chains (alpha1, alpha2, and alpha3), which are encoded by different genes (COL9A1, COL9A2, and COL9A3). Collagen type IX is thought to play a role in the organization and stability of collagen fibrils, as well as in the interaction between collagen and other extracellular matrix components. It has been implicated in various connective tissue disorders, such as Stickler syndrome and Marshall syndrome.

Cell culture is a technique used in scientific research to grow and maintain cells from plants, animals, or humans in a controlled environment outside of their original organism. This environment typically consists of a sterile container called a cell culture flask or plate, and a nutrient-rich liquid medium that provides the necessary components for the cells' growth and survival, such as amino acids, vitamins, minerals, and hormones.

There are several different types of cell culture techniques used in research, including:

1. Adherent cell culture: In this technique, cells are grown on a flat surface, such as the bottom of a tissue culture dish or flask. The cells attach to the surface and spread out, forming a monolayer that can be observed and manipulated under a microscope.
2. Suspension cell culture: In suspension culture, cells are grown in liquid medium without any attachment to a solid surface. These cells remain suspended in the medium and can be agitated or mixed to ensure even distribution of nutrients.
3. Organoid culture: Organoids are three-dimensional structures that resemble miniature organs and are grown from stem cells or other progenitor cells. They can be used to study organ development, disease processes, and drug responses.
4. Co-culture: In co-culture, two or more different types of cells are grown together in the same culture dish or flask. This technique is used to study cell-cell interactions and communication.
5. Conditioned medium culture: In this technique, cells are grown in a medium that has been conditioned by previous cultures of other cells. The conditioned medium contains factors secreted by the previous cells that can influence the growth and behavior of the new cells.

Cell culture techniques are widely used in biomedical research to study cellular processes, develop drugs, test toxicity, and investigate disease mechanisms. However, it is important to note that cell cultures may not always accurately represent the behavior of cells in a living organism, and results from cell culture experiments should be validated using other methods.

The knee joint, also known as the tibiofemoral joint, is the largest and one of the most complex joints in the human body. It is a synovial joint that connects the thighbone (femur) to the shinbone (tibia). The patella (kneecap), which is a sesamoid bone, is located in front of the knee joint and helps in the extension of the leg.

The knee joint is made up of three articulations: the femorotibial joint between the femur and tibia, the femoropatellar joint between the femur and patella, and the tibiofibular joint between the tibia and fibula. These articulations are surrounded by a fibrous capsule that encloses the synovial membrane, which secretes synovial fluid to lubricate the joint.

The knee joint is stabilized by several ligaments, including the medial and lateral collateral ligaments, which provide stability to the sides of the joint, and the anterior and posterior cruciate ligaments, which prevent excessive forward and backward movement of the tibia relative to the femur. The menisci, which are C-shaped fibrocartilaginous structures located between the femoral condyles and tibial plateaus, also help to stabilize the joint by absorbing shock and distributing weight evenly across the articular surfaces.

The knee joint allows for flexion, extension, and a small amount of rotation, making it essential for activities such as walking, running, jumping, and sitting.

The epiphyses are the rounded ends of long bones in the body, which articulate with other bones to form joints. They are separated from the main shaft of the bone (diaphysis) by a growth plate called the physis or epiphyseal plate. The epiphyses are made up of spongy bone and covered with articular cartilage, which allows for smooth movement between bones. During growth, the epiphyseal plates produce new bone cells that cause the bone to lengthen until they eventually fuse during adulthood, at which point growth stops.

Physiologic calcification is the normal deposit of calcium salts in body tissues and organs. It is a natural process that occurs as part of the growth and development of the human body, as well as during the repair and remodeling of tissues.

Calcium is an essential mineral that plays a critical role in many bodily functions, including bone formation, muscle contraction, nerve impulse transmission, and blood clotting. In order to maintain proper levels of calcium in the body, excess calcium that is not needed for these functions may be deposited in various tissues as a normal part of the aging process.

Physiologic calcification typically occurs in areas such as the walls of blood vessels, the lungs, and the heart valves. While these calcifications are generally harmless, they can sometimes lead to complications, particularly if they occur in large amounts or in sensitive areas. For example, calcification of the coronary arteries can increase the risk of heart disease, while calcification of the lung tissue can cause respiratory symptoms.

It is important to note that pathologic calcification, on the other hand, refers to the abnormal deposit of calcium salts in tissues and organs, which can be caused by various medical conditions such as chronic kidney disease, hyperparathyroidism, and certain infections. Pathologic calcification is not a normal process and can lead to serious health complications if left untreated.

Parathyroid Hormone-Related Protein (PTHrP) is a protein that is encoded by the PTHLH gene in humans. It is structurally similar to parathyroid hormone (PTH) and was initially identified due to its role in humoral hypercalcemia of malignancy, a condition characterized by high levels of calcium in the blood caused by certain types of cancer.

PTHrP has a variety of functions in the body, including regulation of calcium and phosphate homeostasis, cell growth and differentiation, and bone metabolism. It acts through a specific G protein-coupled receptor called the PTH/PTHrP receptor, which is found in many tissues throughout the body, including bone, kidney, and cartilage.

In contrast to PTH, which is primarily produced by the parathyroid glands and regulates calcium levels in the blood, PTHrP is produced by many different types of cells throughout the body. Its expression is regulated in a tissue-specific manner, and its functions can vary depending on the context in which it is produced.

Overall, PTHrP plays important roles in normal physiology as well as in various disease states, including cancer, bone disorders, and developmental abnormalities.

Mechanical stress, in the context of physiology and medicine, refers to any type of force that is applied to body tissues or organs, which can cause deformation or displacement of those structures. Mechanical stress can be either external, such as forces exerted on the body during physical activity or trauma, or internal, such as the pressure changes that occur within blood vessels or other hollow organs.

Mechanical stress can have a variety of effects on the body, depending on the type, duration, and magnitude of the force applied. For example, prolonged exposure to mechanical stress can lead to tissue damage, inflammation, and chronic pain. Additionally, abnormal or excessive mechanical stress can contribute to the development of various musculoskeletal disorders, such as tendinitis, osteoarthritis, and herniated discs.

In order to mitigate the negative effects of mechanical stress, the body has a number of adaptive responses that help to distribute forces more evenly across tissues and maintain structural integrity. These responses include changes in muscle tone, joint positioning, and connective tissue stiffness, as well as the remodeling of bone and other tissues over time. However, when these adaptive mechanisms are overwhelmed or impaired, mechanical stress can become a significant factor in the development of various pathological conditions.

The synovial membrane, also known as the synovium, is the soft tissue that lines the inner surface of the capsule of a synovial joint, which is a type of joint that allows for smooth movement between bones. This membrane secretes synovial fluid, a viscous substance that lubricates and nourishes the cartilage and helps to reduce friction within the joint during movement.

The synovial membrane has a highly specialized structure, consisting of two layers: the intima and the subintima. The intima is a thin layer of cells that are in direct contact with the synovial fluid, while the subintima is a more fibrous layer that contains blood vessels and nerves.

The main function of the synovial membrane is to produce and regulate the production of synovial fluid, as well as to provide nutrients to the articular cartilage. It also plays a role in the immune response within the joint, helping to protect against infection and inflammation. However, abnormalities in the synovial membrane can lead to conditions such as rheumatoid arthritis, where the membrane becomes inflamed and produces excess synovial fluid, leading to pain, swelling, and joint damage.

Core Binding Factor Alpha 1 Subunit, also known as CBF-A1 or RUNX1, is a protein that plays a crucial role in hematopoiesis, which is the process of blood cell development. It is a member of the core binding factor (CBF) complex, which regulates gene transcription and is essential for the differentiation and maturation of hematopoietic stem cells into mature blood cells.

The CBF complex consists of three subunits: CBF-A, CBF-B, and a histone deacetylase (HDAC). The CBF-A subunit can have several isoforms, including CBF-A1, which is encoded by the RUNX1 gene. Mutations in the RUNX1 gene have been associated with various hematological disorders, such as acute myeloid leukemia (AML), familial platelet disorder with propensity to develop AML, and thrombocytopenia with absent radii syndrome.

CBF-A1/RUNX1 functions as a transcription factor that binds to DNA at specific sequences called core binding factors, thereby regulating the expression of target genes involved in hematopoiesis. Proper regulation of these genes is essential for normal blood cell development and homeostasis.

Bone Morphogenetic Proteins (BMPs) are a group of growth factors that play crucial roles in the development, growth, and repair of bones and other tissues. They belong to the Transforming Growth Factor-β (TGF-β) superfamily and were first discovered when researchers found that certain proteins extracted from demineralized bone matrix had the ability to induce new bone formation.

BMPs stimulate the differentiation of mesenchymal stem cells into osteoblasts, which are the cells responsible for bone formation. They also promote the recruitment and proliferation of these cells, enhancing the overall process of bone regeneration. In addition to their role in bone biology, BMPs have been implicated in various other biological processes, including embryonic development, wound healing, and the regulation of fat metabolism.

There are several types of BMPs (BMP-2, BMP-4, BMP-7, etc.) that exhibit distinct functions and expression patterns. Due to their ability to stimulate bone formation, recombinant human BMPs have been used in clinical applications, such as spinal fusion surgery and non-healing fracture treatment. However, the use of BMPs in medicine has been associated with certain risks and complications, including uncontrolled bone growth, inflammation, and cancer development, which necessitates further research to optimize their therapeutic potential.

Cell dedifferentiation is a process by which a mature, specialized cell reverts back to an earlier stage in its developmental lineage, regaining the ability to divide and differentiate into various cell types. This phenomenon is typically observed in cells that have been damaged or injured, as well as during embryonic development and certain disease states like cancer. In the context of tissue repair and regeneration, dedifferentiation allows for the generation of new cells with the potential to replace lost or damaged tissues. However, uncontrolled dedifferentiation can also contribute to tumor formation and progression.

'Gene expression regulation' refers to the processes that control whether, when, and where a particular gene is expressed, meaning the production of a specific protein or functional RNA encoded by that gene. This complex mechanism can be influenced by various factors such as transcription factors, chromatin remodeling, DNA methylation, non-coding RNAs, and post-transcriptional modifications, among others. Proper regulation of gene expression is crucial for normal cellular function, development, and maintaining homeostasis in living organisms. Dysregulation of gene expression can lead to various diseases, including cancer and genetic disorders.

The tibia, also known as the shin bone, is the larger of the two bones in the lower leg and part of the knee joint. It supports most of the body's weight and is a major insertion point for muscles that flex the foot and bend the leg. The tibia articulates with the femur at the knee joint and with the fibula and talus bone at the ankle joint. Injuries to the tibia, such as fractures, are common in sports and other activities that put stress on the lower leg.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Sepharose is not a medical term itself, but it is a trade name for a type of gel that is often used in medical and laboratory settings. Sepharose is a type of cross-linked agarose gel, which is derived from seaweed. It is commonly used in chromatography, a technique used to separate and purify different components of a mixture based on their physical or chemical properties.

Sepharose gels are available in various forms, including beads and sheets, and they come in different sizes and degrees of cross-linking. These variations allow for the separation and purification of molecules with different sizes, charges, and other properties. Sepharose is known for its high porosity, mechanical stability, and low non-specific binding, making it a popular choice for many laboratory applications.

C-type lectins are a family of proteins that contain one or more carbohydrate recognition domains (CRDs) with a characteristic pattern of conserved sequence motifs. These proteins are capable of binding to specific carbohydrate structures in a calcium-dependent manner, making them important in various biological processes such as cell adhesion, immune recognition, and initiation of inflammatory responses.

C-type lectins can be further classified into several subfamilies based on their structure and function, including selectins, collectins, and immunoglobulin-like receptors. They play a crucial role in the immune system by recognizing and binding to carbohydrate structures on the surface of pathogens, facilitating their clearance by phagocytic cells. Additionally, C-type lectins are involved in various physiological processes such as cell development, tissue repair, and cancer progression.

It is important to note that some C-type lectins can also bind to self-antigens and contribute to autoimmune diseases. Therefore, understanding the structure and function of these proteins has important implications for developing new therapeutic strategies for various diseases.

Transforming Growth Factor-beta (TGF-β) is a type of cytokine, which is a cell signaling protein involved in the regulation of various cellular processes, including cell growth, differentiation, and apoptosis (programmed cell death). TGF-β plays a critical role in embryonic development, tissue homeostasis, and wound healing. It also has been implicated in several pathological conditions such as fibrosis, cancer, and autoimmune diseases.

TGF-β exists in multiple isoforms (TGF-β1, TGF-β2, and TGF-β3) that are produced by many different cell types, including immune cells, epithelial cells, and fibroblasts. The protein is synthesized as a precursor molecule, which is cleaved to release the active TGF-β peptide. Once activated, TGF-β binds to its receptors on the cell surface, leading to the activation of intracellular signaling pathways that regulate gene expression and cell behavior.

In summary, Transforming Growth Factor-beta (TGF-β) is a multifunctional cytokine involved in various cellular processes, including cell growth, differentiation, apoptosis, embryonic development, tissue homeostasis, and wound healing. It has been implicated in several pathological conditions such as fibrosis, cancer, and autoimmune diseases.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

Matrix metalloproteinases (MMPs) are a group of enzymes responsible for the degradation and remodeling of the extracellular matrix, the structural framework of most tissues in the body. These enzymes play crucial roles in various physiological processes such as tissue repair, wound healing, and embryonic development. They also participate in pathological conditions like tumor invasion, metastasis, and inflammatory diseases by breaking down the components of the extracellular matrix, including collagens, elastins, proteoglycans, and gelatins. MMPs are zinc-dependent endopeptidases that require activation from their proenzyme form to become fully functional. Their activity is tightly regulated at various levels, including gene expression, protein synthesis, and enzyme inhibition by tissue inhibitors of metalloproteinases (TIMPs). Dysregulation of MMPs has been implicated in several diseases, making them potential therapeutic targets for various clinical interventions.

Hyaline cartilage is a type of cartilaginous tissue that is primarily found in the articulating surfaces of bones, ribcage, nose, ears, and trachea. It has a smooth, glassy appearance (hence the name "hyaline," derived from the Greek word "hyalos" meaning glass) due to the presence of type II collagen fibers that are arranged in a precise pattern and embedded in a proteoglycan-rich matrix.

The high concentration of proteoglycans, which are complex molecules made up of a protein core and glycosaminoglycan side chains, gives hyaline cartilage its firm yet flexible properties. This type of cartilage is avascular, meaning it does not contain blood vessels, and receives nutrients through diffusion from the surrounding synovial fluid in joints or adjacent tissues.

Hyaline cartilage plays a crucial role in providing structural support, reducing friction between articulating bones, and facilitating smooth movement in joints. It also serves as a template for endochondral ossification, a process by which long bones grow in length during development.

A joint is the location at which two or more bones make contact. They are constructed to allow movement and provide support and stability to the body during motion. Joints can be classified in several ways, including structure, function, and the type of tissue that forms them. The three main types of joints based on structure are fibrous (or fixed), cartilaginous, and synovial (or diarthrosis). Fibrous joints do not have a cavity and have limited movement, while cartilaginous joints allow for some movement and are connected by cartilage. Synovial joints, the most common and most movable type, have a space between the articular surfaces containing synovial fluid, which reduces friction and wear. Examples of synovial joints include hinge, pivot, ball-and-socket, saddle, and condyloid joints.

In medical terms, ribs are the long, curved bones that make up the ribcage in the human body. They articulate with the thoracic vertebrae posteriorly and connect to the sternum anteriorly via costal cartilages. There are 12 pairs of ribs in total, and they play a crucial role in protecting the lungs and heart, allowing room for expansion and contraction during breathing. Ribs also provide attachment points for various muscles involved in respiration and posture.

Chondroitin sulfates are a type of complex carbohydrate molecules known as glycosaminoglycans (GAGs). They are a major component of cartilage, the tissue that cushions and protects the ends of bones in joints. Chondroitin sulfates are composed of repeating disaccharide units made up of glucuronic acid and N-acetylgalactosamine, which can be sulfated at various positions.

Chondroitin sulfates play a crucial role in the biomechanical properties of cartilage by attracting water and maintaining the resiliency and elasticity of the tissue. They also interact with other molecules in the extracellular matrix, such as collagen and proteoglycans, to form a complex network that provides structural support and regulates cell behavior.

Chondroitin sulfates have been studied for their potential therapeutic benefits in osteoarthritis, a degenerative joint disease characterized by the breakdown of cartilage. Supplementation with chondroitin sulfate has been shown to reduce pain and improve joint function in some studies, although the evidence is not consistent across all trials. The mechanism of action is thought to involve inhibition of enzymes that break down cartilage, as well as stimulation of cartilage repair and synthesis.

High mobility group proteins (HMG proteins) are a family of nuclear proteins that are characterized by their ability to bind to DNA and influence its structure and function. They are named "high mobility" because of their rapid movement in gel electrophoresis. HMG proteins are involved in various nuclear processes, including chromatin remodeling, transcription regulation, and DNA repair.

There are three main classes of HMG proteins: HMGA, HMGB, and HMGN. Each class has distinct structural features and functions. For example, HMGA proteins have a unique "AT-hook" domain that allows them to bind to the minor groove of AT-rich DNA sequences, while HMGB proteins have two "HMG-box" domains that enable them to bend and unwind DNA.

HMG proteins play important roles in many physiological and pathological processes, such as embryonic development, inflammation, and cancer. Dysregulation of HMG protein function has been implicated in various diseases, including neurodegenerative disorders, diabetes, and cancer. Therefore, understanding the structure, function, and regulation of HMG proteins is crucial for developing new therapeutic strategies for these diseases.

Glucosamine is a natural compound found in the body, primarily in the fluid around joints. It is a building block of cartilage, which is the tissue that cushions bones and allows for smooth joint movement. Glucosamine can also be produced in a laboratory and is commonly sold as a dietary supplement.

Medical definitions of glucosamine describe it as a type of amino sugar that plays a crucial role in the formation and maintenance of cartilage, ligaments, tendons, and other connective tissues. It is often used as a supplement to help manage osteoarthritis symptoms, such as pain, stiffness, and swelling in the joints, by potentially reducing inflammation and promoting cartilage repair.

There are different forms of glucosamine available, including glucosamine sulfate, glucosamine hydrochloride, and N-acetyl glucosamine. Glucosamine sulfate is the most commonly used form in supplements and has been studied more extensively than other forms. While some research suggests that glucosamine may provide modest benefits for osteoarthritis symptoms, its effectiveness remains a topic of ongoing debate among medical professionals.

Dinoprostone is a prostaglandin E2 analog used in medical practice for the induction of labor and ripening of the cervix in pregnant women. It is available in various forms, including vaginal suppositories, gel, and tablets. Dinoprostone works by stimulating the contraction of uterine muscles and promoting cervical dilation, which helps in facilitating a successful delivery.

It's important to note that dinoprostone should only be administered under the supervision of a healthcare professional, as its use is associated with certain risks and side effects, including uterine hyperstimulation, fetal distress, and maternal infection. The dosage and duration of treatment are carefully monitored to minimize these risks and ensure the safety of both the mother and the baby.

Tissue scaffolds, also known as bioactive scaffolds or synthetic extracellular matrices, refer to three-dimensional structures that serve as templates for the growth and organization of cells in tissue engineering and regenerative medicine. These scaffolds are designed to mimic the natural extracellular matrix (ECM) found in biological tissues, providing a supportive environment for cell attachment, proliferation, differentiation, and migration.

Tissue scaffolds can be made from various materials, including naturally derived biopolymers (e.g., collagen, alginate, chitosan, hyaluronic acid), synthetic polymers (e.g., polycaprolactone, polylactic acid, poly(lactic-co-glycolic acid)), or a combination of both. The choice of material depends on the specific application and desired properties, such as biocompatibility, biodegradability, mechanical strength, and porosity.

The primary functions of tissue scaffolds include:

1. Cell attachment: Providing surfaces for cells to adhere, spread, and form stable focal adhesions.
2. Mechanical support: Offering a structural framework that maintains the desired shape and mechanical properties of the engineered tissue.
3. Nutrient diffusion: Ensuring adequate transport of nutrients, oxygen, and waste products throughout the scaffold to support cell survival and function.
4. Guided tissue growth: Directing the organization and differentiation of cells through spatial cues and biochemical signals.
5. Biodegradation: Gradually degrading at a rate that matches tissue regeneration, allowing for the replacement of the scaffold with native ECM produced by the cells.

Tissue scaffolds have been used in various applications, such as wound healing, bone and cartilage repair, cardiovascular tissue engineering, and neural tissue regeneration. The design and fabrication of tissue scaffolds are critical aspects of tissue engineering, aiming to create functional substitutes for damaged or diseased tissues and organs.

Mesenchymal Stromal Cells (MSCs) are a type of adult stem cells found in various tissues, including bone marrow, adipose tissue, and umbilical cord blood. They have the ability to differentiate into multiple cell types, such as osteoblasts, chondrocytes, and adipocytes, under specific conditions. MSCs also possess immunomodulatory properties, making them a promising tool in regenerative medicine and therapeutic strategies for various diseases, including autoimmune disorders and tissue injuries. It is important to note that the term "Mesenchymal Stem Cells" has been replaced by "Mesenchymal Stromal Cells" in the scientific community to better reflect their biological characteristics and potential functions.

Osteoblasts are specialized bone-forming cells that are derived from mesenchymal stem cells. They play a crucial role in the process of bone formation and remodeling. Osteoblasts synthesize, secrete, and mineralize the organic matrix of bones, which is mainly composed of type I collagen.

These cells have receptors for various hormones and growth factors that regulate their activity, such as parathyroid hormone, vitamin D, and transforming growth factor-beta. When osteoblasts are not actively producing bone matrix, they can become trapped within the matrix they produce, where they differentiate into osteocytes, which are mature bone cells that play a role in maintaining bone structure and responding to mechanical stress.

Abnormalities in osteoblast function can lead to various bone diseases, such as osteoporosis, osteogenesis imperfecta, and Paget's disease of bone.

Achondroplasia is a genetic disorder that affects bone growth, leading to dwarfism. It is the most common form of short-limbed dwarfism and is caused by a mutation in the FGFR3 gene. This mutation results in impaired endochondral ossification, which is the process by which cartilage is converted into bone.

People with achondroplasia have a characteristic appearance, including:

* Short stature (typically less than 4 feet, 4 inches tall)
* Disproportionately short arms and legs
* Large head with a prominent forehead and flat nasal bridge
* Short fingers with a gap between the middle and ring fingers (known as a trident hand)
* Bowing of the lower legs
* A swayed back (lordosis)

Achondroplasia is usually inherited in an autosomal dominant manner, which means that a child has a 50% chance of inheriting the disorder if one parent has it. However, about 80% of cases result from new mutations in the FGFR3 gene and occur in people with no family history of the condition.

While achondroplasia can cause various medical issues, such as breathing difficulties, ear infections, and spinal cord compression, most individuals with this condition have normal intelligence and a typical lifespan. Treatment typically focuses on managing specific symptoms and addressing any related complications.

In the context of medicine and biology, sulfates are ions or compounds that contain the sulfate group (SO4−2). Sulfate is a polyatomic anion with the structure of a sphere. It consists of a central sulfur atom surrounded by four oxygen atoms in a tetrahedral arrangement.

Sulfates can be found in various biological molecules, such as glycosaminoglycans and proteoglycans, which are important components of connective tissue and the extracellular matrix. Sulfate groups play a crucial role in these molecules by providing negative charges that help maintain the structural integrity and hydration of tissues.

In addition to their biological roles, sulfates can also be found in various medications and pharmaceutical compounds. For example, some laxatives contain sulfate salts, such as magnesium sulfate (Epsom salt) or sodium sulfate, which work by increasing the water content in the intestines and promoting bowel movements.

It is important to note that exposure to high levels of sulfates can be harmful to human health, particularly in the form of sulfur dioxide (SO2), a common air pollutant produced by burning fossil fuels. Prolonged exposure to SO2 can cause respiratory problems and exacerbate existing lung conditions.

ADAM (A Disintegrin And Metalloprotease) proteins are a family of type I transmembrane proteins that contain several distinct domains, including a prodomain, a metalloprotease domain, a disintegrin-like domain, a cysteine-rich domain, a transmembrane domain, and a cytoplasmic tail. These proteins are involved in various biological processes such as cell adhesion, migration, proteolysis, and signal transduction.

ADAM proteins have been found to play important roles in many physiological and pathological conditions, including fertilization, neurodevelopment, inflammation, and cancer metastasis. For example, ADAM12 is involved in the fusion of myoblasts during muscle development, while ADAM17 (also known as TACE) plays a crucial role in the shedding of membrane-bound proteins such as tumor necrosis factor-alpha and epidermal growth factor receptor ligands.

Abnormalities in ADAM protein function have been implicated in various diseases, including cancer, Alzheimer's disease, and arthritis. Therefore, understanding the structure and function of these proteins has important implications for the development of novel therapeutic strategies.

Alkaline phosphatase (ALP) is an enzyme found in various body tissues, including the liver, bile ducts, digestive system, bones, and kidneys. It plays a role in breaking down proteins and minerals, such as phosphate, in the body.

The medical definition of alkaline phosphatase refers to its function as a hydrolase enzyme that removes phosphate groups from molecules at an alkaline pH level. In clinical settings, ALP is often measured through blood tests as a biomarker for various health conditions.

Elevated levels of ALP in the blood may indicate liver or bone diseases, such as hepatitis, cirrhosis, bone fractures, or cancer. Therefore, physicians may order an alkaline phosphatase test to help diagnose and monitor these conditions. However, it is essential to interpret ALP results in conjunction with other diagnostic tests and clinical findings for accurate diagnosis and treatment.

In situ hybridization (ISH) is a molecular biology technique used to detect and localize specific nucleic acid sequences, such as DNA or RNA, within cells or tissues. This technique involves the use of a labeled probe that is complementary to the target nucleic acid sequence. The probe can be labeled with various types of markers, including radioisotopes, fluorescent dyes, or enzymes.

During the ISH procedure, the labeled probe is hybridized to the target nucleic acid sequence in situ, meaning that the hybridization occurs within the intact cells or tissues. After washing away unbound probe, the location of the labeled probe can be visualized using various methods depending on the type of label used.

In situ hybridization has a wide range of applications in both research and diagnostic settings, including the detection of gene expression patterns, identification of viral infections, and diagnosis of genetic disorders.

Cell division is the process by which a single eukaryotic cell (a cell with a true nucleus) divides into two identical daughter cells. This complex process involves several stages, including replication of DNA, separation of chromosomes, and division of the cytoplasm. There are two main types of cell division: mitosis and meiosis.

Mitosis is the type of cell division that results in two genetically identical daughter cells. It is a fundamental process for growth, development, and tissue repair in multicellular organisms. The stages of mitosis include prophase, prometaphase, metaphase, anaphase, and telophase, followed by cytokinesis, which divides the cytoplasm.

Meiosis, on the other hand, is a type of cell division that occurs in the gonads (ovaries and testes) during the production of gametes (sex cells). Meiosis results in four genetically unique daughter cells, each with half the number of chromosomes as the parent cell. This process is essential for sexual reproduction and genetic diversity. The stages of meiosis include meiosis I and meiosis II, which are further divided into prophase, prometaphase, metaphase, anaphase, and telophase.

In summary, cell division is the process by which a single cell divides into two daughter cells, either through mitosis or meiosis. This process is critical for growth, development, tissue repair, and sexual reproduction in multicellular organisms.

Cell proliferation is the process by which cells increase in number, typically through the process of cell division. In the context of biology and medicine, it refers to the reproduction of cells that makes up living tissue, allowing growth, maintenance, and repair. It involves several stages including the transition from a phase of quiescence (G0 phase) to an active phase (G1 phase), DNA replication in the S phase, and mitosis or M phase, where the cell divides into two daughter cells.

Abnormal or uncontrolled cell proliferation is a characteristic feature of many diseases, including cancer, where deregulated cell cycle control leads to excessive and unregulated growth of cells, forming tumors that can invade surrounding tissues and metastasize to distant sites in the body.

Compressive strength is a measure of the maximum compressive load that a material or structure can withstand before failure or deformation. It is typically expressed in units of pressure, such as pounds per square inch (psi) or megapascals (MPa). Compressive strength is an important property in the design and analysis of structures and materials, as it helps to ensure their safety and durability under compressive loads.

In medical terminology, compressive strength may refer to the ability of biological tissues, such as bone or cartilage, to withstand compressive forces without deforming or failing. For example, osteoporosis is a condition characterized by reduced bone density and compressive strength, which can increase the risk of fractures in affected individuals. Similarly, degenerative changes in articular cartilage can lead to decreased compressive strength and joint pain or stiffness.

Cartilage oligomeric matrix protein (COMP) is a extracellular matrix protein that is found in high concentrations in cartilaginous tissues, such as articular cartilage and intervertebral discs. It is a member of the thrombospondin family and plays a role in the organization and stability of the extracellular matrix.
It is also known to be involved in the process of osteoarthritis, a degenerative joint disease. High levels of COMP are found in the synovial fluid of patients with osteoarthritis, and it is thought to contribute to the breakdown of cartilage. Additionally, genetic variations in the COMP gene have been associated with an increased risk of developing osteoarthritis.
It also plays a role in bone development and repair, as well as in the regulation of cell growth and differentiation.

Hydrogels are defined in the medical and biomedical fields as cross-linked, hydrophilic polymer networks that have the ability to swell and retain a significant amount of water or biological fluids while maintaining their structure. They can be synthesized from natural, synthetic, or hybrid polymers.

Hydrogels are known for their biocompatibility, high water content, and soft consistency, which resemble natural tissues, making them suitable for various medical applications such as contact lenses, drug delivery systems, tissue engineering, wound dressing, and biosensors. The physical and chemical properties of hydrogels can be tailored to specific uses by adjusting the polymer composition, cross-linking density, and network structure.

Tissue culture techniques refer to the methods used to maintain and grow cells, tissues or organs from multicellular organisms in an artificial environment outside of the living body, called an in vitro culture. These techniques are widely used in various fields such as biology, medicine, and agriculture for research, diagnostics, and therapeutic purposes.

The basic components of tissue culture include a sterile growth medium that contains nutrients, growth factors, and other essential components to support the growth of cells or tissues. The growth medium is often supplemented with antibiotics to prevent contamination by microorganisms. The cells or tissues are cultured in specialized containers called culture vessels, which can be plates, flasks, or dishes, depending on the type and scale of the culture.

There are several types of tissue culture techniques, including:

1. Monolayer Culture: In this technique, cells are grown as a single layer on a flat surface, allowing for easy observation and manipulation of individual cells.
2. Organoid Culture: This method involves growing three-dimensional structures that resemble the organization and function of an organ in vivo.
3. Co-culture: In co-culture, two or more cell types are grown together to study their interactions and communication.
4. Explant Culture: In this technique, small pieces of tissue are cultured to maintain the original structure and organization of the cells within the tissue.
5. Primary Culture: This refers to the initial culture of cells directly isolated from a living organism. These cells can be further subcultured to generate immortalized cell lines.

Tissue culture techniques have numerous applications, such as studying cell behavior, drug development and testing, gene therapy, tissue engineering, and regenerative medicine.

Hedgehog proteins are a group of signaling molecules that play crucial roles in the development and regulation of various biological processes in animals. They are named after the hedgehog mutant fruit flies, which have spiky bristles due to defects in this pathway. These proteins are involved in cell growth, differentiation, and tissue regeneration. They exert their effects by binding to specific receptors on the surface of target cells, leading to a cascade of intracellular signaling events that ultimately influence gene expression and cell behavior.

There are three main types of Hedgehog proteins in mammals: Sonic hedgehog (Shh), Indian hedgehog (Ihh), and Desert hedgehog (Dhh). These protecules undergo post-translational modifications, including cleavage and lipid modification, which are essential for their activity. Dysregulation of Hedgehog signaling has been implicated in various diseases, including cancer, developmental abnormalities, and degenerative disorders.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

Growth Differentiation Factor 5 (GDF5) is a member of the transforming growth factor-beta (TGF-β) superfamily of proteins, which are involved in various developmental processes such as cell growth, differentiation, and migration. GDF5 plays crucial roles in skeletal development, joint formation, and cartilage maintenance. It is a secreted signaling molecule that binds to specific receptors on the cell surface, activating intracellular signaling pathways that regulate gene expression and ultimately influence cell behavior.

GDF5 has been associated with several genetic disorders affecting the musculoskeletal system, such as brachydactyly type C (shortened fingers or toes), Grebe's recessive chondrodysplasia (disproportionate short stature and joint deformities), and Hunter-Thompson syndrome (a rare skeletal disorder characterized by abnormal bone growth, joint laxity, and other features). Additionally, GDF5 has been implicated in osteoarthritis, a degenerative joint disease, due to its role in maintaining cartilage homeostasis.

Fibroblast Growth Factor Receptor 3 (FGFR3) is a type of cell surface receptor that binds to fibroblast growth factors (FGFs), which are signaling proteins involved in various biological processes such as cell division, growth, and wound healing.

FGFR3 is a transmembrane protein with an extracellular domain that contains the binding site for FGFs, a transmembrane domain, and an intracellular tyrosine kinase domain that activates downstream signaling pathways upon FGF binding.

Mutations in the FGFR3 gene have been associated with several human genetic disorders, including thanatophoric dysplasia, achondroplasia, and hypochondroplasia, which are characterized by abnormal bone growth and development. In these conditions, gain-of-function mutations in FGFR3 lead to increased receptor activity and activation of downstream signaling pathways, resulting in impaired endochondral ossification and short-limbed dwarfism.

In addition to its role in bone growth and development, FGFR3 has been implicated in the regulation of cell proliferation, differentiation, and survival in various tissues, including the brain, lung, and kidney. Dysregulation of FGFR3 signaling has also been associated with cancer, including bladder, breast, and cervical cancers.

Dwarfism is a medical condition that is characterized by short stature, typically with an adult height of 4 feet 10 inches (147 centimeters) or less. It is caused by a variety of genetic and medical conditions that affect bone growth, including skeletal dysplasias, hormonal deficiencies, and chromosomal abnormalities.

Skeletal dysplasias are the most common cause of dwarfism and are characterized by abnormalities in the development and growth of bones and cartilage. Achondroplasia is the most common form of skeletal dysplasia, accounting for about 70% of all cases of dwarfism. It is caused by a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene and results in short limbs, a large head, and a prominent forehead.

Hormonal deficiencies, such as growth hormone deficiency or hypothyroidism, can also cause dwarfism if they are not diagnosed and treated early. Chromosomal abnormalities, such as Turner syndrome (monosomy X) or Down syndrome (trisomy 21), can also result in short stature and other features of dwarfism.

It is important to note that people with dwarfism are not "dwarves" - the term "dwarf" is a medical and sociological term used to describe individuals with this condition, while "dwarves" is a term often used in fantasy literature and media to refer to mythical beings. The use of the term "dwarf" can be considered disrespectful or offensive to some people with dwarfism, so it is important to use respectful language when referring to individuals with this condition.

Bone Morphogenetic Protein 7 (BMP-7) is a growth factor belonging to the transforming growth factor-beta (TGF-β) superfamily. It plays crucial roles in the development and maintenance of various tissues, including bones, cartilages, and kidneys. In bones, BMP-7 stimulates the differentiation of mesenchymal stem cells into osteoblasts, which are bone-forming cells, thereby promoting bone formation and regeneration. It also has potential therapeutic applications in the treatment of various musculoskeletal disorders, such as fracture healing, spinal fusion, and osteoporosis.

I'm sorry for any confusion, but "Hyaluronoglucosaminidase" appears to be a made-up term or a typographical error. The correct term related to hyaluronic acid metabolism is "hyaluronidase," which is an enzyme that degrades hyaluronic acid, a component of the extracellular matrix in various tissues. If you meant to ask about this enzyme or its functions, I'd be happy to provide more information on that. However, if "Hyaluronoglucosaminidase" is intended to represent another medical term, could you please clarify so I can provide an accurate and helpful response?

Up-regulation is a term used in molecular biology and medicine to describe an increase in the expression or activity of a gene, protein, or receptor in response to a stimulus. This can occur through various mechanisms such as increased transcription, translation, or reduced degradation of the molecule. Up-regulation can have important functional consequences, for example, enhancing the sensitivity or response of a cell to a hormone, neurotransmitter, or drug. It is a normal physiological process that can also be induced by disease or pharmacological interventions.

Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).

The Western blotting procedure involves several steps:

1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.

Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.

Apoptosis is a programmed and controlled cell death process that occurs in multicellular organisms. It is a natural process that helps maintain tissue homeostasis by eliminating damaged, infected, or unwanted cells. During apoptosis, the cell undergoes a series of morphological changes, including cell shrinkage, chromatin condensation, and fragmentation into membrane-bound vesicles called apoptotic bodies. These bodies are then recognized and engulfed by neighboring cells or phagocytic cells, preventing an inflammatory response. Apoptosis is regulated by a complex network of intracellular signaling pathways that involve proteins such as caspases, Bcl-2 family members, and inhibitors of apoptosis (IAPs).

The periosteum is a highly vascularized and innervated tissue that surrounds the outer surface of bones, except at the articular surfaces. It consists of two layers: an outer fibrous layer containing blood vessels, nerves, and fibroblasts; and an inner cellular layer called the cambium or osteogenic layer, which contains progenitor cells capable of bone formation and repair.

The periosteum plays a crucial role in bone growth, remodeling, and healing by providing a source of osteoprogenitor cells and blood supply. It also contributes to the sensation of pain in response to injury or inflammation of the bone. Additionally, the periosteum can respond to mechanical stress by activating bone formation, making it an essential component in orthopedic treatments such as distraction osteogenesis.

"Persea" is a botanical term that refers to a genus of plants in the family Lauraceae, which includes over 150 species. The most well-known member of this genus is Persea americana, which is commonly known as the avocado tree. The fruit of this tree, also called an avocado, is widely consumed for its rich, creamy texture and high nutritional value. Avocados are a good source of healthy fats, fiber, vitamins, and minerals, and have been linked to various health benefits.

Therefore, in a medical or nutritional context, "Persea" may refer specifically to the avocado fruit or its extracts, which have been used in traditional medicine for their anti-inflammatory, antioxidant, and hypolipidemic properties. However, it is important to note that not all species of Persea have similar medicinal or nutritional benefits, so any medical or health claims should be specific to the particular species or extract being used.

Insulin-like growth factor I (IGF-I) is a hormone that plays a crucial role in growth and development. It is a small protein with structural and functional similarity to insulin, hence the name "insulin-like." IGF-I is primarily produced in the liver under the regulation of growth hormone (GH).

IGF-I binds to its specific receptor, the IGF-1 receptor, which is widely expressed throughout the body. This binding activates a signaling cascade that promotes cell proliferation, differentiation, and survival. In addition, IGF-I has anabolic effects on various tissues, including muscle, bone, and cartilage, contributing to their growth and maintenance.

IGF-I is essential for normal growth during childhood and adolescence, and it continues to play a role in maintaining tissue homeostasis throughout adulthood. Abnormal levels of IGF-I have been associated with various medical conditions, such as growth disorders, diabetes, and certain types of cancer.

Phosphate transport proteins are membrane-bound proteins responsible for the active transport of phosphate ions across cell membranes. They play a crucial role in maintaining appropriate phosphate concentrations within cells and between intracellular compartments, which is essential for various biological processes such as energy metabolism, signal transduction, and bone formation.

These proteins utilize the energy derived from ATP hydrolysis or other sources to move phosphate ions against their concentration gradient, thereby facilitating cellular uptake of phosphate even when extracellular concentrations are low. Phosphate transport proteins can be classified based on their structure, function, and localization into different types, including sodium-dependent and sodium-independent transporters, secondary active transporters, and channels.

Dysregulation of phosphate transport proteins has been implicated in several pathological conditions, such as renal Fanconi syndrome, tumoral calcinosis, and hypophosphatemic rickets. Therefore, understanding the molecular mechanisms underlying phosphate transport protein function is essential for developing targeted therapies to treat these disorders.

Nitric oxide (NO) is a molecule made up of one nitrogen atom and one oxygen atom. In the body, it is a crucial signaling molecule involved in various physiological processes such as vasodilation, immune response, neurotransmission, and inhibition of platelet aggregation. It is produced naturally by the enzyme nitric oxide synthase (NOS) from the amino acid L-arginine. Inhaled nitric oxide is used medically to treat pulmonary hypertension in newborns and adults, as it helps to relax and widen blood vessels, improving oxygenation and blood flow.

SOXD (SRY-related HMG box gene D) transcription factors are a subgroup of the SOX family of proteins that regulate gene expression during development and differentiation. The SOXD group includes two closely related members, SOX5 and SOX6, which contain a highly conserved HMG (high mobility group) DNA-binding domain. These transcription factors play crucial roles in various biological processes, such as chondrogenesis, neurogenesis, and spermatogenesis, by binding to specific DNA sequences and regulating the transcription of target genes. SOX5 and SOX6 can form heterodimers or homodimers and interact with other transcription factors and cofactors to modulate their activities, contributing to the precise control of gene expression during development.

The sternum, also known as the breastbone, is a long, flat bone located in the central part of the chest. It serves as the attachment point for several muscles and tendons, including those involved in breathing. The sternum has three main parts: the manubrium at the top, the body in the middle, and the xiphoid process at the bottom. The upper seven pairs of ribs connect to the sternum via costal cartilages.

The mandibular condyle is a part of the temporomandibular joint (TMJ) in the human body. It is a rounded eminence at the end of the mandible (lower jawbone) that articulates with the glenoid fossa of the temporal bone in the skull, allowing for movements such as opening and closing the mouth, chewing, speaking, and swallowing. The mandibular condyle has both a fibrocartilaginous articular surface and a synovial joint capsule surrounding it, which provides protection and lubrication during these movements.

Collagen type XI is a fibrillar collagen that is found in the extracellular matrix of various tissues, including cartilage and the eye. It is a homotrimer made up of three identical alpha 1(XI) chains or a heterotrimer composed of two alpha 1(XI) chains and one alpha 2(XI) chain. Collagen type XI is closely associated with collagen type II fibrils and plays a role in regulating the diameter and organization of these fibrils. Mutations in the genes encoding collagen type XI can lead to skeletal disorders such as stiff skin syndrome and fibrodysplasia ossificans progressiva.

Sulfur radioisotopes are unstable forms of the element sulfur that emit radiation as they decay into more stable forms. These isotopes can be used in medical imaging and treatment, such as in the detection and treatment of certain cancers. Common sulfur radioisotopes used in medicine include sulfur-35 and sulfur-32. Sulfur-35 is used in research and diagnostic applications, while sulfur-32 is used in brachytherapy, a type of internal radiation therapy. It's important to note that handling and usage of radioisotopes should be done by trained professionals due to the potential radiation hazards they pose.

Collagen Type I is the most abundant form of collagen in the human body, found in various connective tissues such as tendons, ligaments, skin, and bones. It is a structural protein that provides strength and integrity to these tissues. Collagen Type I is composed of three alpha chains, two alpha-1(I) chains, and one alpha-2(I) chain, arranged in a triple helix structure. This type of collagen is often used in medical research and clinical applications, such as tissue engineering and regenerative medicine, due to its excellent mechanical properties and biocompatibility.

Osteochondritis is a joint condition where a piece of cartilage or bone in the joint separates from its attachment due to a lack of blood supply. This can cause pain, stiffness, and potentially restricted movement in the affected joint. It often occurs in weight-bearing joints like the knee or ankle, and is more common in children and adolescents. The separated piece may sometimes float around in the joint space, causing further damage to the cartilage and bone. If left untreated, it can lead to long-term joint problems. Also known as osteochondrosis or osteochondritis dissecans.

Parathyroid Hormone Receptor Type 1 (PTH1R) is a type of G protein-coupled receptor that binds to parathyroid hormone (PTH) and parathyroid hormone-related peptide (PTHrP). It is primarily found in bone and kidney cells.

The activation of PTH1R by PTH or PTHrP leads to a series of intracellular signaling events that regulate calcium homeostasis, bone metabolism, and renal function. In the bone, PTH1R stimulates the release of calcium from bone matrix into the bloodstream, while in the kidney, it increases the reabsorption of calcium in the distal tubule and inhibits phosphate reabsorption.

Mutations in the gene encoding PTH1R can lead to several genetic disorders, such as Blomstrand chondrodysplasia, Jansen metaphyseal chondrodysplasia, and hypoparathyroidism type 1B. These conditions are characterized by abnormalities in bone development, growth, and mineralization.

The humerus is the long bone in the upper arm that extends from the shoulder joint (glenohumeral joint) to the elbow joint. It articulates with the glenoid cavity of the scapula to form the shoulder joint and with the radius and ulna bones at the elbow joint. The proximal end of the humerus has a rounded head that provides for movement in multiple planes, making it one of the most mobile joints in the body. The greater and lesser tubercles are bony prominences on the humeral head that serve as attachment sites for muscles that move the shoulder and arm. The narrow shaft of the humerus provides stability and strength for weight-bearing activities, while the distal end forms two articulations: one with the ulna (trochlea) and one with the radius (capitulum). Together, these structures allow for a wide range of motion in the shoulder and elbow joints.

Oncostatin M is a cytokine, specifically a member of the interleukin-6 (IL-6) family. It is produced by various cells including T lymphocytes, natural killer cells, and some tumor cells. Oncostatin M plays roles in several biological processes such as inflammation, hematopoiesis, and immune responses. In the context of cancer, it can have both pro-tumoral and anti-tumoral effects depending on the type of cancer and microenvironment. It has been studied for its potential role in cancer therapy due to its ability to inhibit the growth of some tumor cells.

Developmental gene expression regulation refers to the processes that control the activation or repression of specific genes during embryonic and fetal development. These regulatory mechanisms ensure that genes are expressed at the right time, in the right cells, and at appropriate levels to guide proper growth, differentiation, and morphogenesis of an organism.

Developmental gene expression regulation is a complex and dynamic process involving various molecular players, such as transcription factors, chromatin modifiers, non-coding RNAs, and signaling molecules. These regulators can interact with cis-regulatory elements, like enhancers and promoters, to fine-tune the spatiotemporal patterns of gene expression during development.

Dysregulation of developmental gene expression can lead to various congenital disorders and developmental abnormalities. Therefore, understanding the principles and mechanisms governing developmental gene expression regulation is crucial for uncovering the etiology of developmental diseases and devising potential therapeutic strategies.

The femur is the medical term for the thigh bone, which is the longest and strongest bone in the human body. It connects the hip bone to the knee joint and plays a crucial role in supporting the weight of the body and allowing movement during activities such as walking, running, and jumping. The femur is composed of a rounded head, a long shaft, and two condyles at the lower end that articulate with the tibia and patella to form the knee joint.

Chondroitin sulfate proteoglycans (CSPGs) are complex molecules found in the extracellular matrix of various connective tissues, including cartilage. They are composed of a core protein covalently linked to one or more glycosaminoglycan (GAG) chains, such as chondroitin sulfate and dermatan sulfate.

CSPGs play important roles in the structure and function of tissues, including:

1. Regulating water content and providing resilience to tissues due to their high negative charge, which attracts cations and bound water molecules.
2. Interacting with other matrix components, such as collagen and elastin, to form a highly organized network that provides tensile strength and elasticity.
3. Modulating cell behavior by interacting with various growth factors, cytokines, and cell surface receptors, thereby influencing processes like cell adhesion, proliferation, differentiation, and migration.
4. Contributing to the maintenance of the extracellular matrix homeostasis through their involvement in matrix turnover and remodeling.

In articular cartilage, CSPGs are particularly abundant and contribute significantly to its load-bearing capacity and overall health. Dysregulation of CSPGs has been implicated in various pathological conditions, such as osteoarthritis, where altered proteoglycan composition and content can lead to cartilage degradation and joint dysfunction.

Developmental bone diseases are a group of medical conditions that affect the growth and development of bones. These diseases are present at birth or develop during childhood and adolescence, when bones are growing rapidly. They can result from genetic mutations, hormonal imbalances, or environmental factors such as poor nutrition.

Some examples of developmental bone diseases include:

1. Osteogenesis imperfecta (OI): Also known as brittle bone disease, OI is a genetic disorder that affects the body's production of collagen, a protein necessary for healthy bones. People with OI have fragile bones that break easily and may also experience other symptoms such as blue sclerae (whites of the eyes), hearing loss, and joint laxity.
2. Achondroplasia: This is the most common form of dwarfism, caused by a genetic mutation that affects bone growth. People with achondroplasia have short limbs and a large head relative to their body size.
3. Rickets: A condition caused by vitamin D deficiency or an inability to absorb or use vitamin D properly. This leads to weak, soft bones that can bow or bend easily, particularly in children.
4. Fibrous dysplasia: A rare bone disorder where normal bone is replaced with fibrous tissue, leading to weakened bones and deformities.
5. Scoliosis: An abnormal curvature of the spine that can develop during childhood or adolescence. While not strictly a developmental bone disease, scoliosis can be caused by various underlying conditions such as cerebral palsy, muscular dystrophy, or spina bifida.

Treatment for developmental bone diseases varies depending on the specific condition and its severity. Treatment may include medication, physical therapy, bracing, or surgery to correct deformities and improve function. Regular follow-up with a healthcare provider is essential to monitor growth, manage symptoms, and prevent complications.

Metalloproteases are a group of enzymes that require a metal ion as a cofactor for their enzymatic activity. They are also known as matrix metalloproteinases (MMPs) or extracellular proteinases, and they play important roles in various biological processes such as tissue remodeling, wound healing, and cell migration. These enzymes are capable of degrading various types of extracellular matrix proteins, including collagens, gelatins, and proteoglycans. The metal ion cofactor is usually zinc, although other ions such as calcium or cobalt can also be involved. Metalloproteases are implicated in several diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. Inhibitors of metalloproteases have been developed for therapeutic purposes.

The temporomandibular joint (TMJ) is the articulation between the mandible (lower jaw) and the temporal bone of the skull. It's a complex joint that involves the movement of two bones, several muscles, and various ligaments. The TMJ allows for movements like rotation and translation, enabling us to open and close our mouth, chew, speak, and yawn. Dysfunction in this joint can lead to temporomandibular joint disorders (TMD), which can cause pain, discomfort, and limited jaw movement.

Transcription factors are proteins that play a crucial role in regulating gene expression by controlling the transcription of DNA to messenger RNA (mRNA). They function by binding to specific DNA sequences, known as response elements, located in the promoter region or enhancer regions of target genes. This binding can either activate or repress the initiation of transcription, depending on the properties and interactions of the particular transcription factor. Transcription factors often act as part of a complex network of regulatory proteins that determine the precise spatiotemporal patterns of gene expression during development, differentiation, and homeostasis in an organism.

Alcian Blue is a type of dye that is commonly used in histology, which is the study of the microscopic structure of tissues. It is particularly useful for staining acidic mucopolysaccharides and proteoglycans, which are important components of the extracellular matrix in many tissues.

Alcian Blue binds to these negatively charged molecules through ionic interactions, forming a complex that can be visualized under a microscope. The dye is often used in combination with other stains to provide contrast and highlight specific structures within tissues.

The intensity of the Alcian Blue stain can also provide information about the degree of sulfation or carboxylation of the mucopolysaccharides, which can be useful in diagnosing certain diseases or abnormalities. For example, changes in the staining pattern of proteoglycans have been associated with various types of arthritis and other joint disorders.

Overall, Alcian Blue is an important tool in the field of histology and has contributed significantly to our understanding of tissue structure and function.

Glycoproteins are complex proteins that contain oligosaccharide chains (glycans) covalently attached to their polypeptide backbone. These glycans are linked to the protein through asparagine residues (N-linked) or serine/threonine residues (O-linked). Glycoproteins play crucial roles in various biological processes, including cell recognition, cell-cell interactions, cell adhesion, and signal transduction. They are widely distributed in nature and can be found on the outer surface of cell membranes, in extracellular fluids, and as components of the extracellular matrix. The structure and composition of glycoproteins can vary significantly depending on their function and location within an organism.

Cell survival refers to the ability of a cell to continue living and functioning normally, despite being exposed to potentially harmful conditions or treatments. This can include exposure to toxins, radiation, chemotherapeutic drugs, or other stressors that can damage cells or interfere with their normal processes.

In scientific research, measures of cell survival are often used to evaluate the effectiveness of various therapies or treatments. For example, researchers may expose cells to a particular drug or treatment and then measure the percentage of cells that survive to assess its potential therapeutic value. Similarly, in toxicology studies, measures of cell survival can help to determine the safety of various chemicals or substances.

It's important to note that cell survival is not the same as cell proliferation, which refers to the ability of cells to divide and multiply. While some treatments may promote cell survival, they may also inhibit cell proliferation, making them useful for treating diseases such as cancer. Conversely, other treatments may be designed to specifically target and kill cancer cells, even if it means sacrificing some healthy cells in the process.

Cellular mechanotransduction is the process by which cells convert mechanical stimuli into biochemical signals, resulting in changes in cell behavior and function. This complex process involves various molecular components, including transmembrane receptors, ion channels, cytoskeletal proteins, and signaling molecules. Mechanical forces such as tension, compression, or fluid flow can activate these components, leading to alterations in gene expression, protein synthesis, and cell shape or movement. Cellular mechanotransduction plays a crucial role in various physiological processes, including tissue development, homeostasis, and repair, as well as in pathological conditions such as fibrosis and cancer progression.

Cyclooxygenase-2 (COX-2) is an enzyme involved in the synthesis of prostaglandins, which are hormone-like substances that play a role in inflammation, pain, and fever. COX-2 is primarily expressed in response to stimuli such as cytokines and growth factors, and its expression is associated with the development of inflammation.

COX-2 inhibitors are a class of nonsteroidal anti-inflammatory drugs (NSAIDs) that selectively block the activity of COX-2, reducing the production of prostaglandins and providing analgesic, anti-inflammatory, and antipyretic effects. These medications are often used to treat pain and inflammation associated with conditions such as arthritis, menstrual cramps, and headaches.

It's important to note that while COX-2 inhibitors can be effective in managing pain and inflammation, they may also increase the risk of cardiovascular events such as heart attack and stroke, particularly when used at high doses or for extended periods. Therefore, it's essential to use these medications under the guidance of a healthcare provider and to follow their instructions carefully.

Transforming Growth Factor-beta 1 (TGF-β1) is a cytokine that belongs to the TGF-β superfamily. It is a multifunctional protein involved in various cellular processes, including cell growth, differentiation, apoptosis, and extracellular matrix production. TGF-β1 plays crucial roles in embryonic development, tissue homeostasis, and repair, as well as in pathological conditions such as fibrosis and cancer. It signals through a heteromeric complex of type I and type II serine/threonine kinase receptors, leading to the activation of intracellular signaling pathways, primarily the Smad-dependent pathway. TGF-β1 has context-dependent functions, acting as a tumor suppressor in normal and early-stage cancer cells but promoting tumor progression and metastasis in advanced cancers.

p38 Mitogen-Activated Protein Kinases (p38 MAPKs) are a family of conserved serine-threonine protein kinases that play crucial roles in various cellular processes, including inflammation, immune response, differentiation, apoptosis, and stress responses. They are activated by diverse stimuli such as cytokines, ultraviolet radiation, heat shock, osmotic stress, and lipopolysaccharides (LPS).

Once activated, p38 MAPKs phosphorylate and regulate several downstream targets, including transcription factors and other protein kinases. This regulation leads to the expression of genes involved in inflammation, cell cycle arrest, and apoptosis. Dysregulation of p38 MAPK signaling has been implicated in various diseases, such as cancer, neurodegenerative disorders, and autoimmune diseases. Therefore, p38 MAPKs are considered promising targets for developing new therapeutic strategies to treat these conditions.

Down-regulation is a process that occurs in response to various stimuli, where the number or sensitivity of cell surface receptors or the expression of specific genes is decreased. This process helps maintain homeostasis within cells and tissues by reducing the ability of cells to respond to certain signals or molecules.

In the context of cell surface receptors, down-regulation can occur through several mechanisms:

1. Receptor internalization: After binding to their ligands, receptors can be internalized into the cell through endocytosis. Once inside the cell, these receptors may be degraded or recycled back to the cell surface in smaller numbers.
2. Reduced receptor synthesis: Down-regulation can also occur at the transcriptional level, where the expression of genes encoding for specific receptors is decreased, leading to fewer receptors being produced.
3. Receptor desensitization: Prolonged exposure to a ligand can lead to a decrease in receptor sensitivity or affinity, making it more difficult for the cell to respond to the signal.

In the context of gene expression, down-regulation refers to the decreased transcription and/or stability of specific mRNAs, leading to reduced protein levels. This process can be induced by various factors, including microRNA (miRNA)-mediated regulation, histone modification, or DNA methylation.

Down-regulation is an essential mechanism in many physiological processes and can also contribute to the development of several diseases, such as cancer and neurodegenerative disorders.

Procollagen is the precursor protein of collagen, which is a major structural protein in the extracellular matrix of various connective tissues, such as tendons, ligaments, skin, and bones. Procollagen is synthesized inside the cell (in the rough endoplasmic reticulum) and then processed by enzymes to remove specific segments, resulting in the formation of tropocollagen, which are the basic units of collagen fibrils.

Procollagen consists of three polypeptide chains (two alpha-1 and one alpha-2 chain), each containing a central triple-helical domain flanked by non-helical regions at both ends. These non-helical regions, called propeptides, are cleaved off during the processing of procollagen to tropocollagen, allowing the individual collagen molecules to align and form fibrils through covalent cross-linking.

Abnormalities in procollagen synthesis or processing can lead to various connective tissue disorders, such as osteogenesis imperfecta (brittle bone disease) and Ehlers-Danlos syndrome (a group of disorders characterized by joint hypermobility, skin hyperextensibility, and tissue fragility).

Chondroitin is a type of molecule known as a glycosaminoglycan, which is found in the connective tissues of the body, including cartilage. It is a major component of proteoglycans, which are complex molecules that provide structural support and help retain water within the cartilage, allowing it to function as a cushion between joints.

Chondroitin sulfate, a form of chondroitin, is commonly used in dietary supplements for osteoarthritis, a condition characterized by the breakdown of cartilage in joints. The idea behind using chondroitin sulfate as a treatment for osteoarthritis is that it may help to rebuild damaged cartilage and reduce inflammation in the affected joints. However, research on the effectiveness of chondroitin sulfate for osteoarthritis has had mixed results, with some studies showing modest benefits while others have found no significant effects.

It's important to note that dietary supplements containing chondroitin are not regulated by the U.S. Food and Drug Administration (FDA) in the same way that drugs are, so the quality and purity of these products can vary widely. As with any supplement, it's a good idea to talk to your doctor before starting to take chondroitin, especially if you have any medical conditions or are taking other medications.

24,25-Dihydroxyvitamin D3 is a metabolite of vitamin D3, also known as calcitriol. It is formed in the body through the hydroxylation of vitamin D3 by the enzyme 25-hydroxyvitamin D3 1-alpha-hydroxylase, which is primarily found in the kidneys.

24,25-Dihydroxyvitamin D3 plays a role in regulating calcium and phosphate metabolism, but its functions are not as well understood as those of other vitamin D metabolites. Some studies have suggested that it may have anti-inflammatory effects and may be involved in the regulation of cell growth and differentiation. However, more research is needed to fully understand the physiological role of this compound.

It's important to note that 24,25-Dihydroxyvitamin D3 is not typically used as a therapeutic agent, and its levels in the body are not routinely measured in clinical practice.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

"Swine" is a common term used to refer to even-toed ungulates of the family Suidae, including domestic pigs and wild boars. However, in a medical context, "swine" often appears in the phrase "swine flu," which is a strain of influenza virus that typically infects pigs but can also cause illness in humans. The 2009 H1N1 pandemic was caused by a new strain of swine-origin influenza A virus, which was commonly referred to as "swine flu." It's important to note that this virus is not transmitted through eating cooked pork products; it spreads from person to person, mainly through respiratory droplets produced when an infected person coughs or sneezes.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Synovial fluid is a viscous, clear, and straw-colored fluid found in the cavities of synovial joints, bursae, and tendon sheaths. It is produced by the synovial membrane, which lines the inner surface of the capsule surrounding these structures.

The primary function of synovial fluid is to reduce friction between articulating surfaces, providing lubrication for smooth and painless movement. It also acts as a shock absorber, protecting the joints from external forces during physical activities. Synovial fluid contains nutrients that nourish the articular cartilage, hyaluronic acid, which provides its viscoelastic properties, and lubricin, a protein responsible for boundary lubrication.

Abnormalities in synovial fluid composition or volume can indicate joint-related disorders, such as osteoarthritis, rheumatoid arthritis, gout, infection, or trauma. Analysis of synovial fluid is often used diagnostically to determine the underlying cause of joint pain, inflammation, or dysfunction.

Gene expression regulation, enzymologic refers to the biochemical processes and mechanisms that control the transcription and translation of specific genes into functional proteins or enzymes. This regulation is achieved through various enzymatic activities that can either activate or repress gene expression at different levels, such as chromatin remodeling, transcription factor activation, mRNA processing, and protein degradation.

Enzymologic regulation of gene expression involves the action of specific enzymes that catalyze chemical reactions involved in these processes. For example, histone-modifying enzymes can alter the structure of chromatin to make genes more or less accessible for transcription, while RNA polymerase and its associated factors are responsible for transcribing DNA into mRNA. Additionally, various enzymes are involved in post-transcriptional modifications of mRNA, such as splicing, capping, and tailing, which can affect the stability and translation of the transcript.

Overall, the enzymologic regulation of gene expression is a complex and dynamic process that allows cells to respond to changes in their environment and maintain proper physiological function.

Northern blotting is a laboratory technique used in molecular biology to detect and analyze specific RNA molecules (such as mRNA) in a mixture of total RNA extracted from cells or tissues. This technique is called "Northern" blotting because it is analogous to the Southern blotting method, which is used for DNA detection.

The Northern blotting procedure involves several steps:

1. Electrophoresis: The total RNA mixture is first separated based on size by running it through an agarose gel using electrical current. This separates the RNA molecules according to their length, with smaller RNA fragments migrating faster than larger ones.

2. Transfer: After electrophoresis, the RNA bands are denatured (made single-stranded) and transferred from the gel onto a nitrocellulose or nylon membrane using a technique called capillary transfer or vacuum blotting. This step ensures that the order and relative positions of the RNA fragments are preserved on the membrane, similar to how they appear in the gel.

3. Cross-linking: The RNA is then chemically cross-linked to the membrane using UV light or heat treatment, which helps to immobilize the RNA onto the membrane and prevent it from washing off during subsequent steps.

4. Prehybridization: Before adding the labeled probe, the membrane is prehybridized in a solution containing blocking agents (such as salmon sperm DNA or yeast tRNA) to minimize non-specific binding of the probe to the membrane.

5. Hybridization: A labeled nucleic acid probe, specific to the RNA of interest, is added to the prehybridization solution and allowed to hybridize (form base pairs) with its complementary RNA sequence on the membrane. The probe can be either a DNA or an RNA molecule, and it is typically labeled with a radioactive isotope (such as ³²P) or a non-radioactive label (such as digoxigenin).

6. Washing: After hybridization, the membrane is washed to remove unbound probe and reduce background noise. The washing conditions (temperature, salt concentration, and detergent concentration) are optimized based on the stringency required for specific hybridization.

7. Detection: The presence of the labeled probe is then detected using an appropriate method, depending on the type of label used. For radioactive probes, this typically involves exposing the membrane to X-ray film or a phosphorimager screen and analyzing the resulting image. For non-radioactive probes, detection can be performed using colorimetric, chemiluminescent, or fluorescent methods.

8. Data analysis: The intensity of the signal is quantified and compared to controls (such as housekeeping genes) to determine the relative expression level of the RNA of interest. This information can be used for various purposes, such as identifying differentially expressed genes in response to a specific treatment or comparing gene expression levels across different samples or conditions.

... (NC) are present in the hyaline cartilage of the nasal septum and in fact are the only cell type within the ... Similar to other chondrocytes from hyaline cartilage tissues in other locations in the human body, NC undergo a process of cell ... Although articular chondrocytes derived from older individuals have been shown to have a lower proliferation capacity than from ... Articular chondrocytes have typically been the cell type used for cartilage tissue engineering strategies for articular ...
Chondrocytes in hyaline cartilage Transmission electron micrograph of a chondrocyte, stained for calcium, showing its nucleus ( ... While the pug mutation deals with the pre-maturation of chondrocytes, multiple other mutations alter chondrocyte proliferation ... marrow stromal cell Chondrocyte Hypertrophic chondrocyte Mesenchymal (mesoderm origin) stem cells are undifferentiated, meaning ... which are present at high levels in the chondrocyte extracellular matrix and are crucial in regulating chondrocyte maturation. ...
During the implantation, chondrocytes are applied on the damaged area in combination with a membrane (tibial periosteum or ... Autologous chondrocyte implantation (ACI, ATC code M09AX02 (WHO)) is a biomedical treatment that repairs damages in articular ... The patient then undergoes a second treatment, in which the chondrocytes are applied on the damaged area during an open-knee ... The matrix is removed enzymatically and the chondrocytes isolated. These cells are grown in vitro in a specialised laboratory ...
This allows the chondrocyte spheroids to fill in the cartilage defect. Spherox has been shown to improve symptoms and knee ... The chondrocyte spheroids attach to the cartilage within 20 minutes. People treated with Spherox should follow a specific ... The cartilage cells are then grown in the laboratory to prepare a suspension of chondrocyte spheroids. During arthroscopy, the ... Spheroids of human autologous matrix-associated chondrocytes, sold under the brand name Spherox, is a medication used to repair ...
... (Maci) is a treatment to correct cartilage defects in the knee. ... Autologous cultured chondrocytes on porcine collagen membrane was approved for use in the United States in May 2019. ... "Maci (Autologous Cultured Chondrocytes on a Porcine Collagen Membrane)". U.S. Food and Drug Administration (FDA). Retrieved 13 ... Autologous cultured chondrocytes on porcine collagen membrane is an autologous cellularized scaffold product. This treatment is ...
citation needed] Chondrocytes are only present in cartilage where they will produce cartilaginous matrix to maintain the ... These factors also have a role in hypertrophic chondrocyte maturation. β-catenin of the canonical Wnt signalling pathway plays ... Lefebvre, V; Behringer RR; de Crombrugghe B (2001). "L-Sox5, Sox6 and Sox9 control essential steps of the chondrocyte ... They have the ability to differentiate into osteoblasts or chondrocytes depending on the signalling molecules they are exposed ...
The primary center In long bones, bone tissue first appears in the diaphysis (middle of shaft). Chondrocytes multiply and form ...
1996). "Chondrocyte matrix metalloproteinase-8. Human articular chondrocytes express neutrophil collagenase". J. Biol. Chem. ...
Loeser RF (2002). "Integrins and cell signaling in chondrocytes". Biorheology. 39 (1-2): 119-24. PMID 12082274. Overview of all ...
Expression of ENaC, Na+/K+/2Cl- cotransporter and Na+/H+ exchangers in healthy and arthritic chondrocytes". Histol. Histopathol ... "Sodium transport systems in human chondrocytes. II. ...
The chondrocytes are grown and injected into the defect under a periosteal patch. ACI surgery has reported good to excellent ... In this surgery, chondrocytes are arthroscopically extracted from the intercondylar notch of the articular surface. ... One such technique is autologous chondrocyte implantation (ACI), which is useful for large, isolated femoral defects in younger ... Open growth plates are characterized by increased numbers of undifferentiated chondrocytes (stem cells) which are precursors to ...
The chondrocytes present different morphologies related to their position in the tissue. The embryos of Sepia officinalis ... It is a vesicular cell-rich cartilage due to the large, spherical and vacuolated chondrocytes with no homologies in other ... Nutrition is supplied to the chondrocytes by diffusion. The compression of the articular cartilage or flexion of the elastic ... The odontophore contains muscle cells along with the chondrocytes in the case of Lymnaea and other mollusks that graze ...
MSCs can differentiate into osteoblasts, chondrocytes, and adipocytes. In biology, oligopotency is the ability of progenitor ...
Some examples of chondrocytes include collagen and proteoglycans. The chondrocytes that produce chondrocalcin are typically ... This calcium-binding protein comes from chondrocytes, which are cells that produce and maintain cartilage. ... "Chondrocalcin is internalized by chondrocytes and triggers cartilage destruction via an interleukin-1β-dependent pathway, ...
Functions include: Chondrocyte proliferation and bone growth; regulation of cell proliferation, cell adhesion and induction of ... It is expressed on chondrocytes and cardiac muscle. Involved in growth plate morphogenesis and function. Integrin α11β1 is ...
"Synthesis of classical pathway complement components by chondrocytes". Immunology. 88 (4): 648-56. PMC 1456645. PMID 8881771. ...
"Study of Telomere Length in Preimplanted Cultured Chondrocytes". Cartilage. 10 (1): 36-42. doi:10.1177/1947603517749918. PMC ... Stem Cell Exhibiting Pattern Ability and Epigenetic Rejuvenation Study of Telomere Length in Preimplanted Cultured Chondrocytes ...
Depletion of chondrocytes due to apoptosis leads to less ossification and growth slows down and later stops when the entire ... As the older chondrocytes degenerate, osteoblasts ossify the remains to form new bone. In puberty increasing levels of estrogen ... The plate's chondrocytes are under constant division by mitosis. These daughter cells stack facing the epiphysis while the ... Zhong, M; Carney, DH; Boyan, BD; Schwartz, Z (January 2011). "17β-Estradiol regulates rat growth plate chondrocyte apoptosis ...
... a homeoprotein selectively expressed in chondrocytes". Proceedings of the National Academy of Sciences of the United States of ...
It is also found near chondrocytes (cartilage-forming cells). Chondrocytes play a vital role in osteogenesis (the formation of ... Though some chondrocytes do manage to survive, growth is significantly reduced, resulting in the characteristically short limbs ... It is observed at a high frequency in chondrocytes in developing bone and tendon. In pseudochondroplasia, COMP is not secreted ... The researchers found that IX collagen was amassed within the pseudoachondroplasia chondrocytes. This discovery suggests that ...
Remaining chondrocytes divide in order to form more chondroblasts. HMGB-1, a growth factor which promotes chondrocyte division ... Chondroblasts are called chondrocytes when they embed themselves in the cartilage matrix, consisting of proteoglycan and ... These cells are extremely important in chondrogenesis due to their role in forming both the chondrocytes and cartilage matrix ... Higher levels of Wnt14 prevented chondrocyte differentiation whereas lower levels appeared to allow it. If the Wnt/ β-Catenin ...
"ROCK inhibitor prevents the dedifferentiation of human articular chondrocytes". Biochemical and Biophysical Research ... inhibition enhances aggrecan deposition and suppresses matrix metalloproteinase-3 production in human articular chondrocytes". ...
... also has an antiapoptotic effect in osteoarthritic chondrocytes. The precise role of ADAM15 in cancer is still unclear ... 1997). "Expression of members of a novel membrane linked metalloproteinase family (ADAM) in human articular chondrocytes". ... "ADAM15 exerts an antiapoptotic effect on osteoarthritic chondrocytes via up-regulation of the X-linked inhibitor of apoptosis ...
2000). "Regulation of human COL2A1 gene expression in chondrocytes. Identification of C-Krox-responsive elements and modulation ...
... where they are subsequently dissipated and transmitted to chondrocytes (cartilage cells). Chondrocytes sense and convert the ... there need to be mechanoreceptors on the surface of chondrocytes. Candidates for chondrocyte mechanoreceptors include stretch- ... Each chondrocyte has one cilium and it is hypothesized to transmit mechanical signals by way of bending in response to ECM ... Chondrocytes have been shown to secrete TGF-b, and upregulate TGF-b receptors in response to mechanical stimulation; this ...
... structure and transcription pattern in chondrocytes". The Biochemical Journal. 303. 303 ( Pt 1) (Pt 1): 329-33. doi:10.1042/ ...
They are usually highly expressed in cartilage and within chondrocytes. Their genetic transcription increases upon the ...
Craft AM, Ahmed N, Rockel JS, Baht GS, Alman BA, Kandel RA, Grigoriadis AE, Keller GM (2013). "Specification of chondrocytes ... chondrocytes, T lymphocytes and myeloid precursors. Keller holds a Tier I Canada Research Chair in Embryonic Stem Cell Biology ...
2002). "Human articular chondrocytes express three facilitative glucose transporter isoforms: GLUT1, GLUT3 and GLUT9". Cell ... The encoded protein may play a role in the development and survival of chondrocytes in cartilage matrices. Two transcript ... "Cytokine regulation of facilitated glucose transport in human articular chondrocytes". J. Immunol. 167 (12): 7001-8. doi: ... characterization and partial cDNA cloning of facilitative glucose transporters expressed in human articular chondrocytes; ...
Ihh stimulates chondrocyte proliferation and regulates chondrocyte maturation by maintaining the expression of PTHrP. PTHrP ... Because chondrocytes are bound in lacunae, they cannot migrate to damaged areas. Also, because hyaline cartilage does not have ... The expression of Sox9 induces the expression of BMP, which causes chondrocytes to proliferate and differentiate. L-Sox5 and ... The molecule Indian hedgehog (Ihh) is expressed by prehypertrophic chondrocytes. ...
Nasal chondrocytes (NC) are present in the hyaline cartilage of the nasal septum and in fact are the only cell type within the ... Similar to other chondrocytes from hyaline cartilage tissues in other locations in the human body, NC undergo a process of cell ... Although articular chondrocytes derived from older individuals have been shown to have a lower proliferation capacity than from ... Articular chondrocytes have typically been the cell type used for cartilage tissue engineering strategies for articular ...
Pluripotent stem cell-derived chondrocytes for articular cartilage repair. Return to Grants ... Osteoarthritis Cartilage (2019): CaMKII inhibition in human primary and pluripotent stem cell-derived chondrocytes modulates ... Optimization of large-scale production, preservation and quality control of pluripotent stem cell-derived chondrocytes ... Mapping molecular landmarks of human skeletal ontogeny and pluripotent stem cell-derived articular chondrocytes. (PubMed: ...
Dexa increased the apoptosis of canine tendon cells and chondrocytes in a time-dependent manner. In canine tendon cells and ... The results showed that Dexa could inhibit the proliferation of tendon cells and chondrocytes at increasing concentrations (0.1 ... Dexamethasone Induces Apoptosis in Proliferative Canine Tendon Cells and Chondrocytes World Small Animal Veterinary Association ... chondrocytes treated with 25 and 50 µg/ml concentration of Dexa the number of condensed apoptotic nuclei was significantly ...
Within the gp130 cytokine family, OSM is a potent stimulus of chondrocyte responses, while IL-6 probably signals via trans- ... The results of this study highlight a key role for SOCS-3 in regulating chondrocyte responses during inflammatory arthritis. ... The gp130 cytokine-driven production of RANKL in chondrocytes may link chondrocyte activation and bone remodeling during ... Results: On chondrocytes from WT mice, gp130 and the oncostatin M (OSM) receptor were strongly expressed, whereas the ...
This pitfall may be due to the lack of understanding of the mechanisms underlying chondrocyte senescence. Therefore, our study ... Etoposide-induced senescence model may help investigate the initiation of cellular senescence in chondrocytes, and provide a ... On the other hand, etoposide treatment reliably induces DNA damage-related senescence in human articular chondrocytes evidenced ... partial expression of senescence markers and does not allow us to conclude on its ability to induce senescence in chondrocytes ...
We provide evidence that tenocytes have a propensity to differentiate into hypertrophic chondrocyte-like cells to produce TNAP- ... Rotator Cuff Tenocytes Differentiate into Hypertrophic Chondrocyte-Like Cells to Produce Calcium Deposits in an Alkaline ... Rotator Cuff Tenocytes Differentiate into Hypertrophic Chondrocyte-Like Cells to Produce Calcium Deposits in an Alkaline ... Rotator Cuff Tenocytes Differentiate into Hypertrophic Chondrocyte-Like Cells to Produce Calcium Deposits in an Alkaline ...
Wang P, Ye Y, Yuan W, Tan Y, Zhang S and Meng Q: Curcumin exerts a protective effect on murine knee chondrocytes treated with ... Gao ST, Yu YM, Wan LP, Liu ZM and Lin JX: LncRNA GAS5 induces chondrocyte apoptosis by down-regulating miR-137. Eur Rev Med ... Jiang S, Liu Y, Xu B, Zhang Y and Yang M: Noncoding RNAs: New regulatory code in chondrocyte apoptosis and autophagy. Wires RNA ... Tu J, Huang W, Zhang W, Mei J and Zhu C: The emerging role of lncRNAs in chondrocytes from osteoarthritis patients. Biomed ...
... effects of ten oligostilbenes from Paeonia suffruticosa seeds on interleukin-1β-induced rabbit osteoarthritis chondrocytes ... effects of ten oligostilbenes from Paeonia suffruticosa seeds on interleukin-1β-induced rabbit osteoarthritis chondrocytes. ...
A proinflammatory chondrocyte model was created by treating the chondrocytes with lipopolysaccharide and was subsequently used ... A proinflammatory chondrocyte model was created by treating the chondrocytes with lipopolysaccharide and was subsequently used ... Efficient Generation of Chondrocytes From Bone Marrow-Derived Mesenchymal Stem Cells in a 3D Culture System : Protocol for a ... The chondrocytes exhibited reduced inflammation, as evidenced by the decreased tumor necrosis factor-α levels, in response to ...
Chondroprotective activity in human primary chondrocytes assessed as effect on IL-1beta-induced TIMP1 mRNA expression at 200 ug ...
The inhibitory doses had no adverse effect on the viability of chondrocytes. Mechanistic studies revealed no impact on the ... Here, we show that in primary human femoral head osteoarthritic and normal bovine chondrocytes, TWHF partially or completely ... F Extract Suppresses Proinflammatory Cytokine-Induced Expression of Matrix Metalloproteinase Genes in Articular Chondrocytes by ... F Extract Suppresses Proinflammatory Cytokine-Induced Expression of Matrix Metalloproteinase Genes in Articular Chondrocytes by ...
Chondrocyte apoptosis and expression of Bcl-2, Bax, Fas, and iNOS in articular cartilage in patients with Kashin-Beck disease. ... Chondrocyte apoptosis and expression of Bcl-2, Bax, Fas, and iNOS in articular cartilage in patients with Kashin-Beck disease. ... Chondrocyte apoptosis and expression of Bcl-2, Bax, Fas, and iNOS in articular cartilage in patients with Kashin-Beck disease. ... Chondrocyte apoptosis and expression of Bcl-2, Bax, Fas, and iNOS in articular cartilage in patients with Kashin-Beck disease. ...
Hyaluronate is associated with the cell surface of cultured Rous sarcoma virus-transformed chondrocytes. Detachment of these ... Cell-substratum attachment and cell surface hyaluronate of Rous sarcoma virus-transformed chondrocytes. Y Mikuni-Takagaki, Y ... Pericellular coat of chick embryo chondrocytes: structural role of hyaluronate. Binding of hyaluronate to the surface of ... It is proposed that the less readily released fraction is located between the transformed chondrocyte surface and substratum ...
Chondrocytes were isolated from articular cartilage of ten patients with primary OA undergoing knee replacement surgery and six ... While hypertrophy of chondrocytes is a physiological process implicated in the longitudinal growth of long bones, hypertrophy- ... We identified several pathways and proteins to be associated with OA chondrocytes. This study provides evidence for further ... We analyzed the proteome of chondrocytes using high resolution mass spectrometry and quantified it by label-free quantification ...
... Effects of Superoxide Dismutase 1 on cartilage chondrocyte metabolism: a protective mechanism against ankle osteoarthritis? The ...
In vitro chondrocyte hypertrophy and mineralization assay. The hypertrophy and mineralization of chondrocyte was determined by ... Figure 1: Phenotype determination of mice primary chondrocyte. (A) The morphology of normal passage two primary chondrocytes. ( ... To evaluate chondrocyte degeneration, we investigated the function of ECM replacement of chondrocytes under IL-1β stimulation ... Phenotypic determination of primary chondrocytes. The morphology of primary chondrocytes (passage 2) is shown in Figure 1A. The ...
Autologous Chondrocyte Implantation (ACI) is a procedure suitable for larger cartilage defects in the knee (larger than 2 by 3 ... Autologous Chondrocyte Implantation (ACI) is a procedure suitable for larger cartilage defects in the knee (larger than 2 by 3 ...
he most advanced cartilage repair techniques is the articular chondrocyte implantation (ACI), which leads to a normally ... The Basics of Articular Chondrocyte Implantation (ACI). by afarber / Monday, 27 October 2014 / Published in Knee Surgery ... During the second procedure, the surgeon clears the damaged cartilage and implants the cultured chondrocytes. This is usually ... The most advanced cartilage repair techniques is the articular chondrocyte implantation (ACI), which leads to a normally ...
Ultrastructure of chondrocytes of fetal metarsals flown on IML-2, a preliminary report. Gravitational and space biology. 1995;9 ... Ultrastructure of chondrocytes of fetal metarsals flown on IML-2, a preliminary report. / Montufar-Solis, D.; Duke, P.J.; ... Montufar-Solis, D. ; Duke, P.J. ; Veldhuijzen, J.P. / Ultrastructure of chondrocytes of fetal metarsals flown on IML-2, a ... Montufar-Solis, D., Duke, P. J., & Veldhuijzen, J. P. (1995). Ultrastructure of chondrocytes of fetal metarsals flown on IML-2 ...
Pediatric auricular chondrocytes gene expression analysis in monolayer culture and engineered elastic cartilage; Ruszymah BH, ... Stem cell genes are poorly expressed in chondrocytes from microtic cartilage. *Growth kinetic study on normal and microtic ... Pediatric auricular chondrocytes gene expression analysis in monolayer culture and engineered elastic cartilage. ... Specific attentions were to characterize pediatric auricular chondrocyte growth in a combination culture medium and to assess ...
Rituximab and adalimumab were the least toxic agents to chondrocytes, whereas adalimumab and etanercept were to osteocytes. ... on human chondrocytes and osteocytes in vitro. Primary cell cultures obtained from gonarthrosis patients were divided into four ... groups, two of which were designated as control cultures of chondrocyte and osteocyte, and the other two groups were exposed to ... Light microscopy and immunoflow cytometry analysis of chondrocyte and osteocyte primary cell culture. Chondrocytes reached ...
RNA isolation / purification Cells - primary porcine primary chondrocytes. When extracting nucleic acids from cell cultures, ...
Human monocyte or recombinant interleukin 1s are specific for the secretion of a metalloproteinase from chondrocytes.. ... Human monocyte or recombinant interleukin 1s are specific for the secretion of a metalloproteinase from chondrocytes. J ...
GrB and PFN expression is present in normal human articular chondrocytes and elevated in RA chondrocytes. The targets and ... GrB and PFN expression is present in normal human articular chondrocytes and elevated in RA chondrocytes. The targets and ... GrB and PFN expression is present in normal human articular chondrocytes and elevated in RA chondrocytes. The targets and ... GrB and PFN expression is present in normal human articular chondrocytes and elevated in RA chondrocytes. The targets and ...
H3K27ME3 DEMETHYLASES REGULATE IN VITRO CHONDROGENESIS AND CHONDROCYTE ACTIVITY IN OSTEOARTHRITIS Yapp C., Carr AJ., Price AJ ...
... ... Moreover we assay, on NCTC 2544 and chondrocytes cultures, the flavonoids capacity to modulate NO and glycosamminoglycans ... Moreover we assay, on NCTC 2544 and chondrocytes cultures, the flavonoids capacity to modulate NO and glycosamminoglycans ...
We are the worlds largest primary cell provider, with a variety of normal human and animal primary cells frozen at early passage, cell culture media and reagents, growth factors, cell-derived molecular biology products, cell-based assay kits, stem cell products and gene analysis tools.
We established a novel coculture model between BMSC, mixed cultures (BMSC and chondrocytes) and chondrocytes embedded in fibrin ... from chondrocytes and chondrogenically differentiating BMSC cocultured with OAB or NB in comparison with monocultures (cultures ... and induce a phenotypic shift in differentiated OA chondrocytes. ... BMSC and chondrocytes in a ratio of 1:1, dark grey bars) and ... chondrocytes (black bars) were kept as monocultures (dotted lines at 100%) or as co- and tricultures (FB) with NB or OAB ...
Differentiation plasticity of chondrocytes derived from mouse embryonic stem cells. In: Journal of Cell Science. 2002 ; Vol. ... Differentiation plasticity of chondrocytes derived from mouse embryonic stem cells. Journal of Cell Science. 2002 Dec 1;115(23 ... Differentiation plasticity of chondrocytes derived from mouse embryonic stem cells. Claudia Hegert, Jan Kramer, Gunnar Hargus, ... Differentiation plasticity of chondrocytes derived from mouse embryonic stem cells. / Hegert, Claudia; Kramer, Jan; Hargus, ...
... * QMRO Home ... Lithium chloride triggers primary cilia elongation and inhibits hedgehog signalling in articular chondrocytes. dc.contributor. ... Lithium chloride triggers primary cilia elongation and inhibits hedgehog signalling in articular chondrocytes. en_US. ... Lithium chloride triggers primary cilia elongation and inhibits hedgehog signalling in articular chondrocytes ...
  • Similar to chondrocytes present in articular cartilage, NC express extracellular matrix proteins such as glycosaminoglycans and collagen. (wikipedia.org)
  • Articular chondrocytes have typically been the cell type used for cartilage tissue engineering strategies for articular cartilage repair. (wikipedia.org)
  • Long-term repair of porcine articular cartilage using cryopreservable, clinically compatible human embryonic stem cell-derived chondrocytes. (ca.gov)
  • To examine the impact of the gp130 cytokine family on murine articular cartilage and to explore a potential regulatory role of suppressor of cytokine signaling 3 (SOCS-3) in murine chondrocytes. (nih.gov)
  • Chondrocyte apoptosis and expression of Bcl-2, Bax, Fas, and iNOS in articular cartilage in patients with Kashin-Beck disease. (jrheum.org)
  • Chondrocytes were isolated from articular cartilage of ten patients with primary OA undergoing knee replacement surgery and six normal donors undergoing fracture repair surgery without history of joint disease and no OA clinical manifestations. (biomedcentral.com)
  • The most advanced cartilage repair techniques is the articular chondrocyte implantation (ACI), which leads to a normally functioning articular cartilage and provides the stability to the joint. (phoenixshoulderandknee.com)
  • To investigate the expression of granzyme B (GrB) in normal and rheumatoid arthritis (RA) articular cartilage, and to analyze the relationship between the expression of GrB and apoptotic chondrocytes in RA cartilage. (elsevierpure.com)
  • Samples underwent automated controlled freezing at various stages of preparation: as intact articular cartilage discs, as minced articular cartilage, and as chondrocytes immediately after enzymatic isolation from fresh articular cartilage. (ox.ac.uk)
  • This experiment demonstrated that it is possible to isolate viable chondrocytes from cryopreserved intact human articular cartilage which can then be successfully cultured. (ox.ac.uk)
  • The chondrocytes are responsible for the synthesis, maintenance, degradation, and repair of articular cartilage. (drlintner.com)
  • In normal articular cartilage, chondrocytes are exposed to a changing osmotic environment. (ox.ac.uk)
  • Rotator Cuff Tenocytes Differentiate into Hypertrophic Chondrocyte-Like Cells to Produce Calcium Deposits in an Alkaline Phosphatase-Dependent Manner. (iasp-pain.org)
  • Calcifications were amorphous areas surrounded by a fibrocartilaginous metaplasia containing hypertrophic chondrocyte-like cells that expressed tissue non-specific alkaline phosphatase (TNAP) and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which are two key enzymes of the mineralization process. (iasp-pain.org)
  • In vitro, tenocyte-like cells extracted from the rotator cuff were able to mineralize in osteogenic cultures, and expressed , , and , which are hypertrophic chondrocytes markers. (iasp-pain.org)
  • We provide evidence that tenocytes have a propensity to differentiate into hypertrophic chondrocyte-like cells to produce TNAP-dependent calcium deposits. (iasp-pain.org)
  • Here, we show that embryonic stem cells differentiate into chondrocytes, which progressively develop into hypertrophic and calcifying cells. (uni-luebeck.de)
  • At a terminal differentiation stage, cells expressing an osteoblast-like phenotype appeared either by transdifferentiation from hypertrophic chondrocytes or directly from osteoblast precursor cells. (uni-luebeck.de)
  • The first changes to emerge, at the cellular level, involve the cessation of the deposition of inorganic mineral in the cartilaginous tissue, between the hypertrophic columns of chondrocytes. (cdc.gov)
  • Autologous Chondrocyte Implantation (ACI) is a procedure suitable for larger cartilage defects in the knee (larger than 2 by 3 cm). (goravdatta.com)
  • Ultimately, these data support the use of autologous chondrocytes to repair critical maxillofacial defects. (iucc.ac.il)
  • Autologous chondrocyte transplantation (Carticel) was first performed to treat patellar defects in rabbits in 1984. (drlintner.com)
  • Autologous chondrocytes implantation and osteochondral autograft transplantation are limited by scarce cartilage production, low proliferative capacity of chondrocytes, chondrocyte de-differentiation and complications due to donor site morbidity 5 . (nature.com)
  • In the present study we investigated Dexa's in vitro effects on the growth of cell proliferation and the induction of apoptosis in canine Achilles tendon cells and chondrocytes. (vin.com)
  • The results showed that Dexa could inhibit the proliferation of tendon cells and chondrocytes at increasing concentrations (0.1-50 µg/ml) in compared with untreated cells. (vin.com)
  • Dexa increased the apoptosis of canine tendon cells and chondrocytes in a time-dependent manner. (vin.com)
  • In canine tendon cells and chondrocytes treated with 25 and 50 µg/ml concentration of Dexa the number of condensed apoptotic nuclei was significantly increased. (vin.com)
  • In addition, culturing with Dexa and the glucocorticoid receptor blocker mifepristone significantly arrested apoptosis of tendon cells and chondrocytes. (vin.com)
  • Background: Chondrocytes are the primary cells responsible for maintaining cartilage integrity and function. (lu.se)
  • Objective: We developed a novel, streamlined protocol for generating chondrocytes from bone marrow-derived mesenchymal stem cells (BMSCs) in a 3D culture system that offers. (lu.se)
  • Objective: We developed a novel, streamlined protocol for generating chondrocytes from bone marrow-derived mesenchymal stem cells (BMSCs) in a 3D culture system that offers significant implications for the study of cartilage biology and the discovery of potential therapeutic interventions for cartilage-related and associated disorders. (lu.se)
  • Mesenchymal stem cells are activated and differentiate into chondrocytes which produce type I and II collagen to fill the defect. (drlintner.com)
  • MSCs can be differentiated along different cell lineages of mesodermal origin including osteoblasts, chondrocytes, skeletal myocytes or visceral stromal cells 9 . (nature.com)
  • Specifically, the COMP protein is located in the extracellular matrix surrounding the cells that make up ligaments and tendons, and near cartilage-forming cells (chondrocytes). (medlineplus.gov)
  • Achondroplasia is caused by a mutation in the fibroblast growth factor receptor 3 ( FGFR3 ) gene that results in inhibited mineralization of chondrocytes (cartilage cells) in the growth plate (growing tissue near the ends of the long bones). (medscape.com)
  • Chondrocytes have the longest cell cycle in the body (similar to central nervous system and muscle cells). (msdmanuals.com)
  • Inflammatory mediators trigger an inflammatory cycle that further stimulates the chondrocytes and synovial lining cells, eventually breaking down the cartilage. (msdmanuals.com)
  • Articulate cartilage is a firm gel-like complex material, composed of collagenous fibers and cells called chondrocytes. (lu.se)
  • The chondrocyte cells produce proteoglycans which bind to hyaluronic acid, forming large highly hydrophilic aggregates. (lu.se)
  • Here, we show that in primary human femoral head osteoarthritic and normal bovine chondrocytes, TWHF partially or completely inhibited mRNA and protein expression of tumor necrosis factor-α, interleukin (IL)-1, and IL-17-inducible MMP-3 and MMP-13. (aspetjournals.org)
  • We performed a quantitative proteomic analysis in osteoarthritic and normal chondrocytes followed by functional analyses to investigate proteome changes and molecular pathways involved in OA pathogenesis. (biomedcentral.com)
  • Primary cell cultures obtained from gonarthrosis patients were divided into four groups, two of which were designated as control cultures of chondrocyte and osteocyte, and the other two groups were exposed to BAs administered via the culture medium. (biomedcentral.com)
  • Moreover we assay, on NCTC 2544 and chondrocytes cultures, the flavonoids capacity to modulate NO and glycosamminoglycans levels, index of antidegenerative capacity. (unict.it)
  • In clonal cultures of chondrocytes isolated from embryoid bodies, additional mesenchymal cell types expressing adipogenic properties were observed, which suggests that the subcultured chondrocytes indeed exhibit a certain differentiation plasticity. (uni-luebeck.de)
  • As a first step we attempted to induce cartilage mineralization in vitro, using micromass primary chondrocyte cultures, incubated with BMP2 and/or WISP1, which were examined histologically following a 3-week culture period. (iucc.ac.il)
  • Micromass cultures exhibited an osseous inducing trend following WISP1 administration, which was maintained in chondrocyte seeded scaffolds. (iucc.ac.il)
  • On the other hand, etoposide treatment reliably induces DNA damage-related senescence in human articular chondrocytes evidenced by loss of proliferative capacity, DNA damage accumulation, and expression of some SASP components. (aging-us.com)
  • Nasal chondrocytes (NC) are present in the hyaline cartilage of the nasal septum and in fact are the only cell type within the tissue. (wikipedia.org)
  • Moreover, the relative expression level of lncRNA GAS5 in cartilage tissue and chondrocytes was detected using reverse transcription‑quantitative PCR. (spandidos-publications.com)
  • Western blot analysis was used to detect protein expression levels of MMP‑9, MMP‑13, TIMP‑1, TIMP‑3 and type II collagen in cartilage tissue and chondrocytes. (spandidos-publications.com)
  • Furthermore, silencing of lncRNA GAS5 expression in IL‑1β‑treated chondrocytes downregulated the protein expression of MMP-9 and MMP-13 whilst upregulating the expression of tissue inhibitor matrix metalloproteinase (TIMP)-1, TIMP-3 and type II collagen. (spandidos-publications.com)
  • Chondrocytes implanted into critical cranial defect expedite the formation of native-like osseous tissue, especially after WISP1 priming in culture. (iucc.ac.il)
  • We present a comprehensive protocol for studying the volume regulatory behavior of chondrocytes within intact cartilage tissue using confocal laser-scanning microscopy. (ox.ac.uk)
  • We have mapped chondrocyte shape, arrangement, and absolute volume in situ, which vary significantly from the tissue surface through to the underlying bone. (ox.ac.uk)
  • Essed by chondrocytes in naive, AIA and AIA+NBQX rats, and in human OA and RA tissue, where GluRs were abundant near the surface and towards the mid-zone. (nicotinic-receptor.com)
  • The tissue damage stimulates chondrocytes to attempt repair, which increases production of proteoglycans and collagen. (msdmanuals.com)
  • A non-vascular form of connective tissue composed of CHONDROCYTES embedded in a matrix that includes CHONDROITIN SULFATE and various types of FIBRILLAR COLLAGEN. (bvsalud.org)
  • In wild-type (WT) mouse chondrocytes, baseline receptor expression levels and gp130 cytokine-induced JAK/STAT signaling were determined by flow cytometry, and expression of SOCS-3 was assessed by quantitative polymerase chain reaction. (nih.gov)
  • Moreover, wogonoside promoted the expression of anabolic factors Sox-9, type two collagen and aggrecan while inhibiting the expression of catabolic factors such as matrix metalloproteinases (MMPs) and thrombospondin motifs 5 (ADAMTS-5) in mouse chondrocytes. (oncotarget.com)
  • In conclusion, our stduy demonstrates that wogonoside attenuates IL-1β-induced ECM degradation and hypertrophy in mouse chondrocytes via suppressing the activation of NF-κB/HIF-2α by the PI3K/AKT pathway. (oncotarget.com)
  • Developing an accessible and cost-effective model to generate viable chondrocytes and to assess their response to different bioactive compounds can significantly advance our knowledge of cartilage biology and contribute to the discovery of novel therapeutic approaches. (lu.se)
  • Results: The established protocol successfully generated a large quantity of viable chondrocytes, characterized by alcian blue and toluidine blue staining, and demonstrated versatility in assessing the anti-inflammatory effects of various bioactive compounds. (lu.se)
  • We also investigated the effect of WISP-2 on cartilage catabolism and performed WISP-2 loss-of-function experiments using RNA interference technology in human T/C-28a2 immortalized chondrocytes. (harvard.edu)
  • We demonstrated that recombinant human WISP-2 protein reduced IL-1β-mediated chondrocyte catabolism, that IL-1β and WNT/b-catenin signaling pathways are involved in rhWISP-2 protein and IL-1β effects in human chondrocytes, and that WISP-2 has a regulatory role in attenuating the catabolic effects of IL-1β in chondrocytes. (harvard.edu)
  • Cartilage sections were analyzed by immunohistochemistry for the presence of GrB, and the mRNA expression of GrB in chondrocytes was analyzed by in situ hybridization and nonquantitative and semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR). (elsevierpure.com)
  • In situ hybridization and RT-PCR confirmed the expression of GrB and PFN mRNA, and semiquantitative RT-PCR showed elevated concentrations of GrB and PFN expression in RA chondrocytes. (elsevierpure.com)
  • Chondrocytes release HSP105 Storage & Stability glutamate and express AMPA47 and NMDA GluRs.18 NMDA GluR antagonists decrease proliferation and inhibit IL-1 induced increases in cyclooxygenase-2, IL-6 and MMP3 mRNA expression in chondrocytes.18 Having said that, KA GluR expression along with the part of AMPA/KA GluRs have not been reported in chondrocytes. (nicotinic-receptor.com)
  • Treatment of Socs3(Δ/Δcol2) mouse cartilage explants and chondrocytes with gp130 cytokines prolonged JAK/STAT signaling, enhanced cartilage degradation, increased the expression of Adamts4, Adamts5, and RANKL, and elevated the production of IL-6, granulocyte colony-stimulating factor, CXCL1, and CCL2. (nih.gov)
  • The results indicated that ABPS delayed the degradation of the ECM by chondrocytes in addition to reducing lncRNA GAS5 expression both in vivo and in vitro . (spandidos-publications.com)
  • The inflammatory environment is correlated with extracellular matrix (ECM) degradation and chondrocyte hypertrophy in the development of osteoarthritis (OA). (oncotarget.com)
  • The targets and precise functions of GrB expressed in chondrocytes remain to be determined, but GrB may be involved in the remodeling mechanism of matrix macromolecules and the endogenous degradation of RA cartilage. (elsevierpure.com)
  • While hypertrophy of chondrocytes is a physiological process implicated in the longitudinal growth of long bones, hypertrophy-like alterations in chondrocytes play a major role in OA. (biomedcentral.com)
  • Wogonoside also inhibited hypertrophy and the generation of vascular endothelial growth factor (VEGF) in interleukin-1β (IL-1β)-induced chondrocytes. (oncotarget.com)
  • WISP-2 expression is modulated along chondrocyte differentiation and downregulated at the onset of hypertrophy by inflammatory mediators. (harvard.edu)
  • It is 95% water and extracellular cartilage matrix and only 5% chondrocytes. (msdmanuals.com)
  • It was subdivided into type IA, which has apparently normal cartilage matrix but inclusions in chondrocytes, and type IB, which has an abnormal cartilage matrix. (medscape.com)
  • Although articular chondrocytes derived from older individuals have been shown to have a lower proliferation capacity than from younger donors, NC have been shown to have significantly less age-dependence. (wikipedia.org)
  • The viability and proliferation of human chondrocytes following cryopreservation. (ox.ac.uk)
  • Isolated chondrocytes were then cultured and Alamar blue assay was used for estimation of cell proliferation at days zero, four, seven, 14, 21 and 28 after seeding. (ox.ac.uk)
  • Link to all annotated objects annotated to positive regulation of growth plate cartilage chondrocyte proliferation. (planteome.org)
  • With the indicated time point, the chondrocytes had been harvested for even further evaluation which includes cell proliferation, chondrogenic gene expressions (Collagen variety II), and cartilaginous matrix synthesis (Glycosaminoglycan synthesis). (achrinhibitor.com)
  • There may be no major difference in cell proliferation of chondrocytes among three groups. (achrinhibitor.com)
  • Xu XX, Zhang XH, Diao Y and Huang YX: Achyranthes bidentate saponins protect rat articular chondrocytes against interleukin-1β-induced inflammation and apoptosis in vitro. (spandidos-publications.com)
  • Inhibition of proteoglycan biosynthesis by hyaluronic acid in chondrocytes in culture. (bvsalud.org)
  • Similar to other chondrocytes from hyaline cartilage tissues in other locations in the human body, NC undergo a process of cell de-differentiation during monolayer culture. (wikipedia.org)
  • Studies that directly compared the re-differentiation of articular chondrocytes to NC have shown that the cartilage forming capacity of NC was higher and more reproducible than that of articular chondrocytes with lower donor-related dependency. (wikipedia.org)
  • The role of endogenous SOCS-3 was examined in cartilage explants and chondrocytes from mice with conditional deletion of Socs3 driven by the Col2a1 promoter in vitro (Socs3(Δ/Δcol2) ) and from mice during CD4+ T cell-dependent inflammatory monarthritis. (nih.gov)
  • In in vitro experiments, IL‑1β‑treated chondrocytes were infected with Lenti‑lncRNA GAS5. (spandidos-publications.com)
  • used in B-cell-inhibiting treatments on human primary chondrocytes and osteocytes in vitro ). (biomedcentral.com)
  • Next, chondrocyte seeded collagen scaffolds were evaluated in vitro for expression profiles and ALP activity. (iucc.ac.il)
  • This study used etoposide, to induce DNA damage-related senescence or chronic exposure to IL-1β to entail inflammation-related senescence in human OA chondrocytes. (aging-us.com)
  • The chondrocytes exhibited reduced inflammation, as evidenced by the decreased tumor necrosis factor-α levels, in response to vitamin D, curcumin, and resveratrol treatment. (lu.se)
  • The results of this study highlight a key role for SOCS-3 in regulating chondrocyte responses during inflammatory arthritis. (nih.gov)
  • The gp130 cytokine-driven production of RANKL in chondrocytes may link chondrocyte activation and bone remodeling during inflammatory arthritis. (nih.gov)
  • A proinflammatory chondrocyte model was created by treating the chondrocytes with lipopolysaccharide and was subsequently used to evaluate the anti-inflammatory effects of vitamin D, curcumin, and resveratrol. (lu.se)
  • Conclusions: Our novel protocol offers an accessible and cost-effective approach for generating chondrocytes from BMSCs and for evaluating potential therapeutic leads in the context of inflammatory chondrocyte-related diseases. (lu.se)
  • In osteoarthritis (OA), the most common form of arthritis, chondrocytes exhibit aberrant and increased production of pro-inflammatory mediators and matrix degrading enzymes such as IL-1β and MMP-13. (harvard.edu)
  • Gene silencing of WISP-2 increased the induction of the catabolic markers MMP-13 and ADAMTS-5 and the inflammatory mediators IL-6 and IL-8 triggered by IL-1β in human primary OA chondrocytes in a Wnt/β-catenin dependent manner. (harvard.edu)
  • Here we show that bone marrow endosteal SSCs are defined by fibroblast growth factor receptor 3 ( Fgfr3 ) and osteoblast-chondrocyte transitional (OCT) identities with some characteristics of bone osteoblasts and chondrocytes. (nature.com)
  • Of note, we define OCT identities as a state with some characteristics of both osteoblasts and chondrocytes, instead of cell-type plasticity between osteoblasts and chondrocytes. (nature.com)
  • Methods: We developed a streamlined protocol for generating chondrocytes from BMSCs in a 3D culture system using an "in-tube" culture approach. (lu.se)
  • Although our approach has several advantages, further investigation is required to address its limitations, such as the potential differences between chondrocytes generated using our protocol and those derived from other established methods, and to refine the model for broader applicability and clinical translation. (lu.se)
  • Finally, chondrocyte-seeded collagen scaffolds were implanted in a Lewis rats 8 mm critical calvaria defect model, which was imaged via live CT for 12 weeks until sacrifice. (iucc.ac.il)
  • Accordingly, in vivo analysis was carried out to assess the impact of WISP1-pretreated chondrocytes (WCS) versus untreated chondrocytes (UCS) in calvaria defect model and compared to untreated control comprised of a defect-associated blood clot (BC) or empty collagen scaffold (CS) implant. (iucc.ac.il)
  • AC is composed of an extracellular matrix of mainly type II hyaline collagen and proteoglycan aggregate produced by a small population of chondrocytes. (drlintner.com)
  • Fluorescence in situ hybridization assay was performed to measure the expression of the lncRNA GAS5 in chondrocytes. (spandidos-publications.com)
  • The combined techniques of confocal laser-scanning microscopy and vital cell labeling have enabled us to study, for the first time, the response of chondrocytes in situ to changes in interstitial osmotic pressure. (ox.ac.uk)
  • In this study, we report a novel population of SSCs with osteoblast-chondrocyte transitional (OCT) identities in the bone marrow endosteal space, which highly expresses Fgfr3 and contributes to both normal and aberrant osteogenesis. (nature.com)
  • Vosoritide, a biologic analog of C-type natriuretic peptide, prevents the inhibition of mineralization of chondrocytes caused by the FGFR3 mutation. (medscape.com)
  • Ultrastructure of chondrocytes of fetal metarsals flown on IML-2, a preliminary report. (vu.nl)
  • CaMKII inhibition in human primary and pluripotent stem cell-derived chondrocytes modulates effects of TGFbeta and BMP through SMAD signaling. (ca.gov)
  • Mapping molecular landmarks of human skeletal ontogeny and pluripotent stem cell-derived articular chondrocytes. (ca.gov)
  • Specific attentions were to characterize pediatric auricular chondrocyte growth in a combination culture medium and to assess the possibility of elastic cartilage regeneration using human fibrin. (afpm.org.my)
  • Are biological agents toxic to human chondrocytes and osteocytes? (biomedcentral.com)
  • Human monocyte or recombinant interleukin 1's are specific for the secretion of a metalloproteinase from chondrocytes. (ucdenver.edu)
  • GrB and PFN expression is present in normal human articular chondrocytes and elevated in RA chondrocytes. (elsevierpure.com)
  • ADAM-8 isolated from human osteoarthritic chondrocytes cleaves fibronectin at Ala(271). (rush.edu)
  • In the present study, we determined the expression of WISP-2 in healthy and OA human chondrocytes. (harvard.edu)
  • Atrix synthesis of human articular chondrocytes. (achrinhibitor.com)
  • Summary/conclusion: ADSCs enhances chondrogenesis and matrix synthesis of human articular chondrocytes is mediated by EVsantimicrobial action test, Staphylococcus aureus (S. aureus) was cultured in LB broth medium at 37, O/ N. The seed culture ratio (1/100, 1/1000) and different exosome concentration were inoculated and development was confirmed by time. (achrinhibitor.com)
  • This study provides evidence for further testing on the molecular mechanism of the disease and also propose proteins as candidate markers of OA chondrocyte phenotype. (biomedcentral.com)
  • Chronic exposure to IL-1β induces only partial expression of senescence markers and does not allow us to conclude on its ability to induce senescence in chondrocytes. (aging-us.com)
  • To conclude, the present study provides evidence that ABPS can inhibit the expression of lncRNA GAS5 in chondrocytes to regulate the homeostasis of ECM, which in turn may delay the occurrence of cartilage degeneration during OA. (spandidos-publications.com)
  • Sun X, Zhang J, Li Y, Ren W and Wang L: Etomidate ameliorated advanced glycation end-products (AGEs)-induced reduction of extracellular matrix genes expression in chondrocytes. (spandidos-publications.com)
  • The immunohistochemical analyses revealed GrB and PFN expression in normal chondrocytes and a larger number of GrB and PFN-positive chondrocytes in RA cartilage. (elsevierpure.com)
  • The chondrogenic gene expression and cartilaginous matrix synthesis of chondrocyte is significantly enhanced in conditioned medium group when in contrast with management group. (achrinhibitor.com)
  • High level of expression detected in chondrocytes. (lu.se)
  • Effects of Superoxide Dismutase 1 on cartilage chondrocyte metabolism: a protective mechanism against ankle osteoarthritis? (cardiff.ac.uk)
  • The inhibitory doses had no adverse effect on the viability of chondrocytes. (aspetjournals.org)
  • Any process that increases the rate, frequency, or extent of the multiplication or reproduction of chondrocytes in a growing endochondral bone, resulting in the expansion of a cell population. (planteome.org)
  • Chondrocytes play an important role in bone formation (osteogenesis). (medlineplus.gov)
  • We show that the presence of tandem-repeat-type galectin-8 significantly correlated with cartilage degeneration and that it is secreted by osteoarthritic chondrocytes. (nih.gov)
  • Researchers believe that the lack of COMP protein in the spaces between the chondrocytes leads to the formation of abnormal cartilage. (medlineplus.gov)
  • COMP mutations: domain-dependent relationship between abnormal chondrocyte trafficking and clinical PSACH and MED phenotypes. (medlineplus.gov)
  • Within the gp130 cytokine family, OSM is a potent stimulus of chondrocyte responses, while IL-6 probably signals via trans-signaling. (nih.gov)
  • These results show that translational control provides a rapid and potentially important mechanism for controlling the synthetic responses of articular chondrocytes in response to different types of mechanical load. (ox.ac.uk)
  • Therefore, our study aimed to generate models of chondrocyte senescence. (aging-us.com)