Alkaline Phosphatase: An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC Phosphatases: A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992)Acid Phosphatase: An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC Tyrosine Phosphatases: An enzyme group that specifically dephosphorylates phosphotyrosyl residues in selected proteins. Together with PROTEIN-TYROSINE KINASE, it regulates tyrosine phosphorylation and dephosphorylation in cellular signal transduction and may play a role in cell growth control and carcinogenesis.Protein Phosphatase 2: A phosphoprotein phosphatase subtype that is comprised of a catalytic subunit and two different regulatory subunits. At least two genes encode isoforms of the protein phosphatase catalytic subunit, while several isoforms of regulatory subunits exist due to the presence of multiple genes and the alternative splicing of their mRNAs. Protein phosphatase 2 acts on a broad variety of cellular proteins and may play a role as a regulator of intracellular signaling processes.Protein Phosphatase 1: A eukayrotic protein serine-threonine phosphatase subtype that dephosphorylates a wide variety of cellular proteins. The enzyme is comprised of a catalytic subunit and regulatory subunit. Several isoforms of the protein phosphatase catalytic subunit exist due to the presence of multiple genes and the alternative splicing of their mRNAs. A large number of proteins have been shown to act as regulatory subunits for this enzyme. Many of the regulatory subunits have additional cellular functions.Phosphoric Monoester Hydrolases: A group of hydrolases which catalyze the hydrolysis of monophosphoric esters with the production of one mole of orthophosphate. EC 3.1.3.Glucose-6-Phosphatase: An enzyme that catalyzes the conversion of D-glucose 6-phosphate and water to D-glucose and orthophosphate. EC Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.Hypophosphatasia: A genetic metabolic disorder resulting from serum and bone alkaline phosphatase deficiency leading to hypercalcemia, ethanolamine phosphatemia, and ethanolamine phosphaturia. Clinical manifestations include severe skeletal defects resembling vitamin D-resistant rickets, failure of the calvarium to calcify, dyspnea, cyanosis, vomiting, constipation, renal calcinosis, failure to thrive, disorders of movement, beading of the costochondral junction, and rachitic bone changes. (From Dorland, 27th ed)Bone and Bones: 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.Osteoblasts: Bone-forming cells which secrete an EXTRACELLULAR MATRIX. HYDROXYAPATITE crystals are then deposited into the matrix to form bone.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Phosphates: Inorganic salts of phosphoric acid.Osteocalcin: Vitamin K-dependent calcium-binding protein synthesized by OSTEOBLASTS and found primarily in BONES. Serum osteocalcin measurements provide a noninvasive specific marker of bone metabolism. The protein contains three residues of the amino acid gamma-carboxyglutamic acid (Gla), which, in the presence of CALCIUM, promotes binding to HYDROXYAPATITE and subsequent accumulation in BONE MATRIX.Calcification, Physiologic: Process by which organic tissue becomes hardened by the physiologic deposit of calcium salts.Dual-Specificity Phosphatases: A sub-class of protein tyrosine phosphatases that contain an additional phosphatase activity which cleaves phosphate ester bonds on SERINE or THREONINE residues that are located on the same protein.Protein Tyrosine Phosphatase, Non-Receptor Type 11: A subtype of non-receptor protein tyrosine phosphatases that contain two SRC HOMOLOGY DOMAINS. Mutations in the gene for protein tyrosine phosphatase, non-receptor type 11 are associated with NOONAN SYNDROME.cdc25 Phosphatases: A subclass of dual specificity phosphatases that play a role in the progression of the CELL CYCLE. They dephosphorylate and activate CYCLIN-DEPENDENT KINASES.Protein Tyrosine Phosphatase, Non-Receptor Type 1: A subtype of non-receptor protein tyrosine phosphatases that includes two distinctive targeting motifs; an N-terminal motif specific for the INSULIN RECEPTOR, and a C-terminal motif specific for the SH3 domain containing proteins. This subtype includes a hydrophobic domain which localizes it to the ENDOPLASMIC RETICULUM.Placenta: A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (CHORIONIC VILLI) derived from TROPHOBLASTS and a maternal portion (DECIDUA) derived from the uterine ENDOMETRIUM. The placenta produces an array of steroid, protein and peptide hormones (PLACENTAL HORMONES).Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Okadaic Acid: A specific inhibitor of phosphoserine/threonine protein phosphatase 1 and 2a. It is also a potent tumor promoter. (Thromb Res 1992;67(4):345-54 & Cancer Res 1993;53(2):239-41)Osteogenesis: The process of bone formation. Histogenesis of bone including ossification.Protein Tyrosine Phosphatase, Non-Receptor Type 6: A Src-homology domain-containing protein tyrosine phosphatase found in the CYTOSOL of hematopoietic cells. It plays a role in signal transduction by dephosphorylating signaling proteins that are activated or inactivated by PROTEIN-TYROSINE KINASES.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Myosin-Light-Chain Phosphatase: A phosphoprotein phosphatase that is specific for MYOSIN LIGHT CHAINS. It is composed of three subunits, which include a catalytic subunit, a myosin binding subunit, and a third subunit of unknown function.Kinetics: The rate dynamics in chemical or physical systems.TetramisoleProtein Tyrosine Phosphatases, Non-Receptor: A subcategory of protein tyrosine phosphatases that occur in the CYTOPLASM. Many of the proteins in this category play a role in intracellular signal transduction.Phosphorylase Phosphatase: An enzyme that deactivates glycogen phosphorylase a by releasing inorganic phosphate and phosphorylase b, the inactive form. EC A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.HomoarginineHistocytochemistry: Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.Receptor-Like Protein Tyrosine Phosphatases, Class 2: A subclass of receptor-like protein tryosine phosphatases that contain multiple extracellular immunoglobulin G-like domains and fibronectin type III-like domains. An additional memprin-A5-mu domain is found on some members of this subclass.gamma-Glutamyltransferase: An enzyme, sometimes called GGT, with a key role in the synthesis and degradation of GLUTATHIONE; (GSH, a tripeptide that protects cells from many toxins). It catalyzes the transfer of the gamma-glutamyl moiety to an acceptor amino acid.Ethers, Cyclic: Compounds of the general formula R-O-R arranged in a ring or crown formation.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Phosphatidate Phosphatase: A phosphomonoesterase involved in the synthesis of triacylglycerols. It catalyzes the hydrolysis of phosphatidates with the formation of diacylglycerols and orthophosphate. EC An antihelminthic drug that has been tried experimentally in rheumatic disorders where it apparently restores the immune response by increasing macrophage chemotaxis and T-lymphocyte function. Paradoxically, this immune enhancement appears to be beneficial in rheumatoid arthritis where dermatitis, leukopenia, and thrombocytopenia, and nausea and vomiting have been reported as side effects. (From Smith and Reynard, Textbook of Pharmacology, 1991, p435-6)Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Cells, Cultured: 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.Intestines: The section of the alimentary canal from the STOMACH to the ANAL CANAL. It includes the LARGE INTESTINE and SMALL INTESTINE.Dual Specificity Phosphatase 1: A dual specificity phosphatase subtype that plays a role in intracellular signal transduction by inactivating MITOGEN-ACTIVATED PROTEIN KINASES. It has specificity for P38 MITOGEN-ACTIVATED PROTEIN KINASES and JNK MITOGEN-ACTIVATED PROTEIN KINASES.NitrophenolsBase Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Phosphorus: A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.Signal Transduction: 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.Enzyme Activation: Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.Clinical Enzyme Tests: Analyses for a specific enzyme activity, or of the level of a specific enzyme that is used to assess health and disease risk, for early detection of disease or disease prediction, diagnosis, and change in disease status.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Nucleotidases: A class of enzymes that catalyze the conversion of a nucleotide and water to a nucleoside and orthophosphate. EC 3.1.3.-.Aspartate Aminotransferases: Enzymes of the transferase class that catalyze the conversion of L-aspartate and 2-ketoglutarate to oxaloacetate and L-glutamate. EC, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Electrophoresis, Cellulose Acetate: Electrophoresis in which cellulose acetate is the diffusion medium.Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Receptor-Like Protein Tyrosine Phosphatases, Class 3: A subclass of receptor-like protein tryosine phosphatases that contain a single cytosolic protein tyrosine phosphate domain and multiple extracellular fibronectin III-like domains.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.TartratesBone Morphogenetic Protein 2: A potent osteoinductive protein that plays a critical role in the differentiation of osteoprogenitor cells into OSTEOBLASTS.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Receptor-Like Protein Tyrosine Phosphatases, Class 4: A subclass of receptor-like protein tryosine phosphatases that contain short highly glycosylated extracellular domains and two active cytosolic protein tyrosine phosphatase domains.Zinc: A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.Osteomalacia: Disorder caused by an interruption of the mineralization of organic bone matrix leading to bone softening, bone pain, and weakness. It is the adult form of rickets resulting from disruption of VITAMIN D; PHOSPHORUS; or CALCIUM homeostasis.Mitogen-Activated Protein Kinase Phosphatases: A subcategory of phosphohydrolases that are specific for MITOGEN-ACTIVATED PROTEIN KINASES. They play a role in the inactivation of the MAP KINASE SIGNALING SYSTEM.Osteitis Deformans: A disease marked by repeated episodes of increased bone resorption followed by excessive attempts at repair, resulting in weakened, deformed bones of increased mass. The resultant architecture of the bone assumes a mosaic pattern in which the fibers take on a haphazard pattern instead of the normal parallel symmetry.Molecular Weight: The sum of the weight of all the atoms in a molecule.Vanadates: Oxyvanadium ions in various states of oxidation. They act primarily as ion transport inhibitors due to their inhibition of Na(+)-, K(+)-, and Ca(+)-ATPase transport systems. They also have insulin-like action, positive inotropic action on cardiac ventricular muscle, and other metabolic effects.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Bone Diseases: Diseases of BONES.Enzyme Inhibitors: Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.Parathyroid Hormone: A polypeptide hormone (84 amino acid residues) secreted by the PARATHYROID GLANDS which performs the essential role of maintaining intracellular CALCIUM levels in the body. Parathyroid hormone increases intracellular calcium by promoting the release of CALCIUM from BONE, increases the intestinal absorption of calcium, increases the renal tubular reabsorption of calcium, and increases the renal excretion of phosphates.Core Binding Factor Alpha 1 Subunit: 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.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Organophosphorus Compounds: Organic compounds that contain phosphorus as an integral part of the molecule. Included under this heading is broad array of synthetic compounds that are used as PESTICIDES and DRUGS.Dual Specificity Phosphatase 6: A dual specificity phosphatase subtype that plays a role in intracellular signal transduction by inactivating MITOGEN-ACTIVATED PROTEIN KINASES. It has specificity for EXTRACELLULAR SIGNAL-REGULATED MAP KINASES and is primarily localized to the CYTOSOL.Protein Tyrosine Phosphatase, Non-Receptor Type 2: A subtype of non-receptor protein tyrosine phosphatase that is closely-related to PROTEIN TYROSINE PHOSPHATASE, NON-RECEPTOR TYPE 1. Alternative splicing of the mRNA for this phosphatase results in the production at two gene products, one of which includes a C-terminal nuclear localization domain that may be involved in the transport of the protein to the CELL NUCLEUS. Although initially referred to as T-cell protein tyrosine phosphatase the expression of this subtype occurs widely.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Calcineurin: A CALCIUM and CALMODULIN-dependent serine/threonine protein phosphatase that is composed of the calcineurin A catalytic subunit and the calcineurin B regulatory subunit. Calcineurin has been shown to dephosphorylate a number of phosphoproteins including HISTONES; MYOSIN LIGHT CHAIN; and the regulatory subunits of CAMP-DEPENDENT PROTEIN KINASES. It is involved in the regulation of signal transduction and is the target of an important class of immunophilin-immunosuppressive drug complexes.Enzyme Induction: An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.Oxazoles: Five-membered heterocyclic ring structures containing an oxygen in the 1-position and a nitrogen in the 3-position, in distinction from ISOXAZOLES where they are at the 1,2 positions.Magnesium: A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.Phosphoric Diester Hydrolases: A class of enzymes that catalyze the hydrolysis of one of the two ester bonds in a phosphodiester compound. EC 3.1.4.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Bone Matrix: Extracellular substance of bone tissue consisting of COLLAGEN fibers, ground substance, and inorganic crystalline minerals and salts.4-Nitrophenylphosphatase: An enzyme that catalyzes the hydrolysis of nitrophenyl phosphates to nitrophenols. At acid pH it is probably ACID PHOSPHATASE (EC; at alkaline pH it is probably ALKALINE PHOSPHATASE (EC EC Domain-Containing Protein Tyrosine Phosphatases: A subcategory of protein tyrosine phosphatases that contain SH2 type SRC HOMOLOGY DOMAINS. Many of the proteins in this class are recruited to specific cellular targets such as a cell surface receptor complexes via their SH2 domain.RNA, Messenger: 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.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Microvilli: Minute projections of cell membranes which greatly increase the surface area of the cell.Cattle: 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.Biological Markers: Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.Bone Remodeling: The continuous turnover of BONE MATRIX and mineral that involves first an increase in BONE RESORPTION (osteoclastic activity) and later, reactive BONE FORMATION (osteoblastic activity). The process of bone remodeling takes place in the adult skeleton at discrete foci. The process ensures the mechanical integrity of the skeleton throughout life and plays an important role in calcium HOMEOSTASIS. An imbalance in the regulation of bone remodeling's two contrasting events, bone resorption and bone formation, results in many of the metabolic bone diseases, such as OSTEOPOROSIS.Choriocarcinoma: A malignant metastatic form of trophoblastic tumors. Unlike the HYDATIDIFORM MOLE, choriocarcinoma contains no CHORIONIC VILLI but rather sheets of undifferentiated cytotrophoblasts and syncytiotrophoblasts (TROPHOBLASTS). It is characterized by the large amounts of CHORIONIC GONADOTROPIN produced. Tissue origins can be determined by DNA analyses: placental (fetal) origin or non-placental origin (CHORIOCARCINOMA, NON-GESTATIONAL).Collagen Type I: 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.Liver Function Tests: Blood tests that are used to evaluate how well a patient's liver is working and also to help diagnose liver conditions.Bilirubin: A bile pigment that is a degradation product of HEME.Alanine Transaminase: An enzyme that catalyzes the conversion of L-alanine and 2-oxoglutarate to pyruvate and L-glutamate. (From Enzyme Nomenclature, 1992) EC Proteins: Proteins prepared by recombinant DNA technology.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Liver Diseases: Pathological processes of the LIVER.SucrasePTEN Phosphohydrolase: A lipid phosphatase that acts on phosphatidylinositol-3,4,5-trisphosphate to regulate various SIGNAL TRANSDUCTION PATHWAYS. It modulates CELL GROWTH PROCESSES; CELL MIGRATION; and APOPTOSIS. Mutations in PTEN are associated with COWDEN DISEASE and PROTEUS SYNDROME as well as NEOPLASTIC CELL TRANSFORMATION.GPI-Linked Proteins: A subclass of lipid-linked proteins that contain a GLYCOSYLPHOSPHATIDYLINOSITOL LINKAGE which holds them to the CELL MEMBRANE.Bacterial Proteins: Proteins found in any species of bacterium.Protein Kinases: A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.Glycerophosphates: Any salt or ester of glycerophosphoric acid.Glycogen-Synthase-D Phosphatase: An enzyme that catalyzes the conversion of phosphorylated, inactive glycogen synthase D to active dephosphoglycogen synthase I. EC Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Rickets: Disorders caused by interruption of BONE MINERALIZATION manifesting as OSTEOMALACIA in adults and characteristic deformities in infancy and childhood due to disturbances in normal BONE FORMATION. The mineralization process may be interrupted by disruption of VITAMIN D; PHOSPHORUS; or CALCIUM homeostasis, resulting from dietary deficiencies, or acquired, or inherited metabolic, or hormonal disturbances.Bone Resorption: Bone loss due to osteoclastic activity.Gene Expression Regulation, Enzymologic: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in enzyme synthesis.Pyrophosphatases: A group of enzymes within the class EC 3.6.1.- that catalyze the hydrolysis of diphosphate bonds, chiefly in nucleoside di- and triphosphates. They may liberate either a mono- or diphosphate. EC 3.6.1.-.Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Bone Density: The amount of mineral per square centimeter of BONE. This is the definition used in clinical practice. Actual bone density would be expressed in grams per milliliter. It is most frequently measured by X-RAY ABSORPTIOMETRY or TOMOGRAPHY, X RAY COMPUTED. Bone density is an important predictor for OSTEOPOROSIS.Diphosphates: Inorganic salts of phosphoric acid that contain two phosphate groups.Microcystins: Cyclic heptapeptides found in MICROCYSTIS and other CYANOBACTERIA. Hepatotoxic and carcinogenic effects have been noted. They are sometimes called cyanotoxins, which should not be confused with chemicals containing a cyano group (CN) which are toxic.PhosphoproteinsElectrophoresis: An electrochemical process in which macromolecules or colloidal particles with a net electric charge migrate in a solution under the influence of an electric current.Osteopontin: A negatively-charged extracellular matrix protein that plays a role in the regulation of BONE metabolism and a variety of other biological functions. Cell signaling by osteopontin may occur through a cell adhesion sequence that recognizes INTEGRIN ALPHA-V BETA-3.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Receptor-Like Protein Tyrosine Phosphatases, Class 5: A subclass of receptor-like protein tryosine phosphatases that contain an extracellular fibronectin III-like domain along with a carbonic anhydrase-like domain.Intracellular Signaling Peptides and Proteins: Proteins and peptides that are involved in SIGNAL TRANSDUCTION within the cell. Included here are peptides and proteins that regulate the activity of TRANSCRIPTION FACTORS and cellular processes in response to signals from CELL SURFACE RECEPTORS. Intracellular signaling peptide and proteins may be part of an enzymatic signaling cascade or act through binding to and modifying the action of other signaling factors.Rabbits: 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.Leucyl Aminopeptidase: A zinc containing enzyme of the hydrolase class that catalyzes the removal of the N-terminal amino acid from most L-peptides, particularly those with N-terminal leucine residues but not those with N-terminal lysine or arginine residues. This occurs in tissue cell cytosol, with high activity in the duodenum, liver, and kidney. The activity of this enzyme is commonly assayed using a leucine arylamide chromogenic substrate such as leucyl beta-naphthylamide.Pyruvate Dehydrogenase (Lipoamide)-Phosphatase: (Pyruvate dehydrogenase (lipoamide))-phosphate phosphohydrolase. A mitochondrial enzyme that catalyzes the hydrolytic removal of a phosphate on a specific seryl hydroxyl group of pyruvate dehydrogenase, reactivating the enzyme complex. EC Domain: The region of an enzyme that interacts with its substrate to cause the enzymatic reaction.Cantharidin: A toxic compound, isolated from the Spanish fly or blistering beetle (Lytta (Cantharis) vesicatoria) and other insects. It is a potent and specific inhibitor of protein phosphatases 1 (PP1) and 2A (PP2A). This compound can produce severe skin inflammation, and is extremely toxic if ingested orally.Protein Tyrosine Phosphatase, Non-Receptor Type 12: A subtype of non-receptor protein tyrosine phosphatases that is characterized by the presence of a N-terminal catalytic domain and a large C-terminal domain that is enriched in PROLINE, GLUTAMIC ACID, SERINE, and THREONINE residues (PEST sequences). The phosphatase subtype is ubiquitously expressed and implicated in the regulation of a variety of biological processes such as CELL MOVEMENT; CYTOKINESIS; focal adhesion disassembly; and LYMPHOCYTE ACTIVATION.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Intestine, Small: The portion of the GASTROINTESTINAL TRACT between the PYLORUS of the STOMACH and the ILEOCECAL VALVE of the LARGE INTESTINE. It is divisible into three portions: the DUODENUM, the JEJUNUM, and the ILEUM.Dual Specificity Phosphatase 3: A dual specificity phosphatase subtype that plays a role in intracellular signal transduction by inactivating MITOGEN-ACTIVATED PROTEIN KINASES. It has specificity for EXTRACELLULAR SIGNAL-REGULATED MAP KINASES.Enzyme Repression: The interference in synthesis of an enzyme due to the elevated level of an effector substance, usually a metabolite, whose presence would cause depression of the gene responsible for enzyme synthesis.Subcellular Fractions: Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)Proteins: Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Cholestasis: Impairment of bile flow due to obstruction in small bile ducts (INTRAHEPATIC CHOLESTASIS) or obstruction in large bile ducts (EXTRAHEPATIC CHOLESTASIS).Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Dysgerminoma: A malignant ovarian neoplasm, thought to be derived from primordial germ cells of the sexually undifferentiated embryonic gonad. It is the counterpart of the classical seminoma of the testis, to which it is both grossly and histologically identical. Dysgerminomas comprise 16% of all germ cell tumors but are rare before the age of 10, although nearly 50% occur before the age of 20. They are generally considered of low-grade malignancy but may spread if the tumor extends through its capsule and involves lymph nodes or blood vessels. (Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1646)Blotting, Western: 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.Wheat Germ Agglutinins: Lectins purified from the germinating seeds of common wheat (Triticum vulgare); these bind to certain carbohydrate moieties on cell surface glycoproteins and are used to identify certain cell populations and inhibit or promote some immunological or physiological activities. There are at least two isoforms of this lectin.Minerals: Native, inorganic or fossilized organic substances having a definite chemical composition and formed by inorganic reactions. They may occur as individual crystals or may be disseminated in some other mineral or rock. (Grant & Hackh's Chemical Dictionary, 5th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Osteosarcoma: A sarcoma originating in bone-forming cells, affecting the ends of long bones. It is the most common and most malignant of sarcomas of the bones, and occurs chiefly among 10- to 25-year-old youths. (From Stedman, 25th ed)Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Receptor-Like Protein Tyrosine Phosphatases: A subcategory of protein tyrosine phosphatases that are bound to the cell membrane. They contain cytoplasmic tyrosine phosphatase domains and extracellular protein domains that may play a role in cell-cell interactions by interacting with EXTRACELLULAR MATRIX components. They are considered receptor-like proteins in that they appear to lack specific ligands.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Renal Osteodystrophy: Decalcification of bone or abnormal bone development due to chronic KIDNEY DISEASES, in which 1,25-DIHYDROXYVITAMIN D3 synthesis by the kidneys is impaired, leading to reduced negative feedback on PARATHYROID HORMONE. The resulting SECONDARY HYPERPARATHYROIDISM eventually leads to bone disorders.Butyric Acid: A four carbon acid, CH3CH2CH2COOH, with an unpleasant odor that occurs in butter and animal fat as the glycerol ester.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Protein Tyrosine Phosphatase, Non-Receptor Type 13: A subtype of non-receptor protein tyrosine phosphatases that is characterized by the presence of an amino-terminal FERM domain, an intervening region containing five different PDZ domains, and a carboxyl-terminal phosphatase domain. In addition to playing a role as a regulator of the FAS RECEPTOR activity this subtype interacts via its PDZ and FERM domains with a variety of INTRACELLULAR SIGNALING PROTEINS and CYTOSKELETAL PROTEINS.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Blood Chemical Analysis: An examination of chemicals in the blood.Protein Tyrosine Phosphatase, Non-Receptor Type 3: A subtype of non-receptor protein tyrosine phosphatases that is characterized by the presence of an amino-terminal FERM domain, an intervening region containing one or more PDZ domains, and a carboxyl-terminal phosphatase domain. Expression of this phosphatase subtype has been observed in BONE MARROW; fetal LIVER; LYMPH NODES; and T LYMPHOCYTES.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.L-Lactate Dehydrogenase: A tetrameric enzyme that, along with the coenzyme NAD+, catalyzes the interconversion of LACTATE and PYRUVATE. In vertebrates, genes for three different subunits (LDH-A, LDH-B and LDH-C) exist.Protein-Serine-Threonine Kinases: A group of enzymes that catalyzes the phosphorylation of serine or threonine residues in proteins, with ATP or other nucleotides as phosphate donors.Phosphatidylinositol Diacylglycerol-Lyase: A phosphorus-oxygen lyase found primarily in BACTERIA. The enzyme catalyzes the cleavage of a phosphoester linkage in 1-phosphatidyl-1D-myo-inositol to form 1D-myo-inositol 1,2-cyclic phosphate and diacylglycerol. The enzyme was formerly classified as a phosphoric diester hydrolase (EC and is often referred to as a TYPE C PHOSPHOLIPASES. However it is now known that a cyclic phosphate is the final product of this enzyme and that water does not enter into the reaction.Glycosylphosphatidylinositols: Compounds containing carbohydrate or glycosyl groups linked to phosphatidylinositols. They anchor GPI-LINKED PROTEINS or polysaccharides to cell membranes.5'-Nucleotidase: A glycoprotein enzyme present in various organs and in many cells. The enzyme catalyzes the hydrolysis of a 5'-ribonucleotide to a ribonucleoside and orthophosphate in the presence of water. It is cation-dependent and exists in a membrane-bound and soluble form. EC An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.Mesenchymal Stromal Cells: 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.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Integrin-Binding Sialoprotein: A highly glycosylated and sulfated phosphoprotein that is found almost exclusively in mineralized connective tissues. It is an extracellular matrix protein that binds to hydroxyapatite through polyglutamic acid sequences and mediates cell attachment through an RGD sequence.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Butyrates: Derivatives of BUTYRIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxypropane structure.Cartilage: 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.Phosphorus Radioisotopes: Unstable isotopes of phosphorus that decay or disintegrate emitting radiation. P atoms with atomic weights 28-34 except 31 are radioactive phosphorus isotopes.Immunoenzyme Techniques: Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.Bone Development: 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.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Bone Morphogenetic Proteins: 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.Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.Intestinal Mucosa: Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.Precipitin Tests: Serologic tests in which a positive reaction manifested by visible CHEMICAL PRECIPITATION occurs when a soluble ANTIGEN reacts with its precipitins, i.e., ANTIBODIES that can form a precipitate.DisaccharidasesBone Neoplasms: Tumors or cancer located in bone tissue or specific BONES.Skull: The SKELETON of the HEAD including the FACIAL BONES and the bones enclosing the BRAIN.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Serine: A non-essential amino acid occurring in natural form as the L-isomer. It is synthesized from GLYCINE or THREONINE. It is involved in the biosynthesis of PURINES; PYRIMIDINES; and other amino acids.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Rats, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.Phosphotyrosine: An amino acid that occurs in endogenous proteins. Tyrosine phosphorylation and dephosphorylation plays a role in cellular signal transduction and possibly in cell growth control and carcinogenesis.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.Digoxigenin: 3 beta,12 beta,14-Trihydroxy-5 beta-card-20(22)-enolide. A cardenolide which is the aglycon of digoxin. Can be obtained by hydrolysis of digoxin or from Digitalis orientalis L. and Digitalis lanata Ehrh.Gene Expression Regulation: 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.Hydrolases: Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.Cytoplasm: The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Enzymes: Biological molecules that possess catalytic activity. They may occur naturally or be synthetically created. Enzymes are usually proteins, however CATALYTIC RNA and CATALYTIC DNA molecules have also been identified.Swine: 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).Amino Acids: Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.Chromatography, Ion Exchange: Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.