Paraffin
Paraffin Embedding
Tissue Fixation
Formaldehyde
Fixatives
Immunoenzyme Techniques
Immunohistochemistry
Frozen Sections
Microtomy
Staining and Labeling
Waxes
Tissue Preservation
Plastic Embedding
Histocytological Preparation Techniques
Mineral Oil
Tissue Embedding
Tumor Markers, Biological
Polymerase Chain Reaction
Biopsy
Hematoxylin
In Situ Hybridization
Nucleolus Organizer Region
Oils
Ki-67 Antigen
Histocytochemistry
Neoplasm Proteins
Palatine Tonsil
Eosine Yellowish-(YS)
Pathology, Molecular
Silver Staining
In Situ Hybridization, Fluorescence
Tissue Array Analysis
Prognosis
Antigens, Neoplasm
Proliferating Cell Nuclear Antigen
Microwaves
Adenofibroma
Sensitivity and Specificity
Carcinoma, Squamous Cell
Lymph Nodes
Digoxigenin
Periodic Acid-Schiff Reaction
Retrospective Studies
Emulsions
Diathermy
Receptors, Estrogen
Keratins
Keratin-13
Lymphoma, T-Cell
Loss of PTEN expression in paraffin-embedded primary prostate cancer correlates with high Gleason score and advanced stage. (1/216)
The tumor suppressor gene PTEN/MMAC-1/TEP-1 (referred to hereafter as PTEN) maps to chromosome 10q23 and encodes a dual specificity phosphatase. The PTEN protein negatively regulates cell migration and cell survival and induces a G1 cell cycle block via negative regulation of the phosphatidylinositol 3'-kinase/protein kinase B/Akt signaling pathway. PTEN is frequently mutated or deleted in both prostate cancer cell lines and primary prostate cancers. A murine polyclonal antiserum was raised against a glutathione S-transferase fusion polypeptide of the COOH terninus of PTEN. Archival paraffin tissue sections from 109 cases of resected prostate cancer were immunostained with the antiserum, using DU145 and PC-3 cells as positive and negative controls, respectively. PTEN expression was seen in the secretory cells. Cases were considered positive when granular cytoplasmic staining was seen in all tumor cells, mixed when areas of both positive and negative tumor cell clones were seen, and negative when adjacent benign prostate tissue but not tumor tissue showed positive staining. Seventeen cases (15.6%) of prostate cancer were positive, 70 cases (64.2%) were mixed, and 22 cases (20.2%) were negative. Total absence of PTEN expression correlated with the Gleason score (P = 0.0081) and correlated more significantly with a Gleason score of 7 or higher (P = 0.0004) and with advanced pathological stage (American Joint Committee on Cancer stages T3b and T4; P = 0.0078). Thus, loss of PTEN protein is correlated with pathological markers of poor prognosis in prostate cancer. (+info)Recovery of ranavirus dsDNA from formalin-fixed archival material. (2/216)
The extraction and amplification of nucleic acid from formalin-fixed and paraffin-embedded tissues has become an important exercise in the collection of retrospective epidemiological data. A protocol is described that enables the extraction and amplification of dsDNA from fixed tissues within paraffin blocks and from specimens stored in 10% (aq) formalin. The procedure can be used for the examination of ranavirus DNA within archival tissues thereby providing valuable data for identifying the origin and tracing the spread of ranaviruses. (+info)Relation between antigen release and immune response of oil adjuvanted vaccines in chickens. (3/216)
The relationship between release properties of the model antigen, bovine serum albumin (BSA), from formulations in vitro and immune response after administration of various oil adjuvanted vaccines containing liquid paraffin was examined in chickens. The vaccine prepared at an hydrophile-lipophile-balance (HLB) number of 4.8 showed slower release of BSA and higher immune response on injected chickens than that with an HLB number of 6.0. Decreases of aqueous volume ratio in the formulation also led to slower release of BSA and higher immune response. The slower release rate of BSA showed higher ELISA antibody titer even at 20 weeks after vaccination. The ELISA antibody titer inversely was related to the constant release rate, k, calculated from the in vitro release test. The correlation coefficient was 0.863. The immune response of oil adjuvanted vaccines containing Haemophilus paragallinarum agreed well with these results with BSA. Our results indicated that a stronger and more prolonged immune response of oil adjuvanted vaccines was achieved by slower release rate of antigen from the formulation. In addition, there was a good correlation between immune response and the value of k. (+info)Immunofluorescent detection of alpha1-antitrypsin in paraffin embedded liver tissue. (4/216)
Alpha1-antitrypsin was detected by indirect immunofluorescence in frozen sections of liver biopsies from patients with clinically and biochemically proven alpha1-antitrypsin deficiency. The antigen could also be demonstrated in those liver specimens of the same patients which were fixed in Bouin's fluid and embedded in paraffin. The cellular localization and the brightness of the fluorescence were the same in both frozen and paraffin sections. Four additional biopsies from three other patients were selected on the basis of PAS-positive diastase-resistant inclusions reported in the hepatocytes. All these biopsies showed bright fluorescence in the cytoplasm of the liver cells although one of the biopsies was stored for as long as eight years. Specific fluorescence was constantly found in the periportal hepatocytes with varying degrees of positivity. No fluorescence was observed in the six control biopsies from patients with various other liver diseases. These findings prove that paraffin embedded specimens are suitable for immunofluorescence detection of alpha1-antitrypsin and that a retrospective study on old paraffin blocks is possible. (+info)Cutaneous necrosis due to cetrimide application. (5/216)
Reports of necrosis caused by quaternary ammonium compounds, such as cetrimide, are rare. The case is reported of a 77-year-old woman who was admitted to hospital for four months with cutaneous necrosis of the left foot and leg owing to the topical application of cetrimide powder. (+info)Congenital-infantile fibrosarcoma. A clinicopathologic study of 10 cases and molecular detection of the ETV6-NTRK3 fusion transcripts using paraffin-embedded tissues. (6/216)
Congenital-infantile fibrosarcoma (CIFS) is a relatively indolent sarcoma that should be distinguished from more aggressive spindle cell sarcomas of childhood. CIFSs have been found to have a novel recurrent reciprocal translocation t(12;15)(p13;q25) resulting in the gene fusion ETV6-NTRK3 (ETS variant gene 6; neurotrophic tyrosine kinase receptor type 3). We studied immunohistochemical expression of NTRK3, and conducted a reverse transcription-polymerase chain reaction (RT-PCR) assay to detect the ETV6-NTRK3 fusion transcripts using archival formalin-fixed paraffin-embedded tissues from 10 CIFSs. Thirty-eight other spindle cell tumors were included as controls. The ETV6-NTRK3 fusion transcripts were identified in 7 (70%) of 10 CIFSs. Nucleotide sequence analysis showed that the fusion occurred between ETV6 exon 5 and NTRK3 exon 13. The 38 control tumors were negative for the fusion transcript. Immunohistochemically, CIFSs consistently expressed NTRK3. But the expression of NTRK3 also was observed in 22 of 38 control tumors. These results show the diagnostic usefulness of RT-PCR methods to detect ETV6-NTRK3 fusion transcripts in archival formalin-fixed paraffin-embedded tissue and the important role of NTRK3 in the development of CIFS, despite its being a protein of little importance in differential diagnosis. (+info)Increasing the number of synapses modifies olfactory perception in Drosophila. (7/216)
The Drosophila mutant gigas produces an enlargement of postmitotic cells caused by additional rounds of DNA replication. In neurons, the mutant cell establishes more synapses than normal. We have taken advantage of this feature to study the effect of synapse number on odorant perception. Mosaic adults were generated in which one antenna was homozygous for gigas, whereas the contralateral side served as an internal control. Morphological analysis indicates that the number and type of sensory afferents forming the mutant antenna, as well as their projection to the olfactory glomeruli, are normal. In contrast, the volume of identified glomeruli increases to a variable extent, and mutant sensory neurons branch profusely. The number of synapses, estimated in the ventral (V) glomerulus that receives ipsilateral afferents only, is increased twofold to threefold. Large-dense-core vesicle-containing terminals that probably modulate olfactory centers are identified in the V glomerulus. Their number and size are not modified by the mutant input. Sensory transduction, measured by electroantennograms, is normal in amplitude and kinetics. In odorant tests, however, the profile of the behavioral response to ethyl acetate shows attractive responses to concentrations to which sibling controls remain indifferent (10(-)8 and 10(-)7 v/v). In addition, the intensity of the response is augmented both at attractive and repulsive odorant concentrations with respect to that of controls. These results demonstrate that increased synapse number in the sensory neurons can modify the behavior of the organism, allowing a higher sensitivity of perception. (+info)Cyclin D1 overexpression in multiple myeloma. A morphologic, immunohistochemical, and in situ hybridization study of 71 paraffin-embedded bone marrow biopsy specimens. (8/216)
Cyclin D1 expression was evaluated by immunohistochemical analysis and biotin-labeled in situ hybridization (ISH) in a series of 71 decalcified, paraffin-embedded bone marrow biopsy specimens from patients with multiple myeloma (MM). Cyclin D1 messenger RNA (mRNA) overexpression was detected by ISH in 23 (32%) of 71 cases, whereas cyclin D1 protein was identified by immunohistochemical analysis in 17 (24%) of 71 specimens. All cases that were positive by immunohistochemical analysis also were positive by ISH. Statistically significant associations were found between cyclin D1 overexpression and grade of plasma cell differentiation and between cyclin D1 overexpression and extent of bone marrow infiltration. Our findings demonstrate the following: (1) ISH for cyclin D1 mRNA is a sensitive method for the evaluation of cyclin D1 overexpression in paraffin-embedded bone marrow biopsy specimens with MM. (2) ISH is more sensitive than immunohistochemical analysis in the assessment of cyclin D1 expression. (3) Cyclin D1 overexpression in MM is correlated positively with higher histologic grade and stage. (+info)In a medical context, paraffin is often referred to as "medical-grade paraffin," which is a type of mineral wax that is highly refined and purified for use in various medical applications. It is typically used in the form of paraffin baths for heat therapy, where a part of the body is dipped into a bath of melted paraffin to provide soothing warmth and pain relief. Medical-grade paraffin is colorless, odorless, tasteless, and chemically stable, making it safe for topical use on the skin. It has a high melting point and does not conduct electricity, which also makes it suitable for use in certain types of medical equipment and supplies.
Paraffin embedding is a process in histology (the study of the microscopic structure of tissues) where tissue samples are impregnated with paraffin wax to create a solid, stable block. This allows for thin, uniform sections of the tissue to be cut and mounted on slides for further examination under a microscope.
The process involves fixing the tissue sample with a chemical fixative to preserve its structure, dehydrating it through a series of increasing concentrations of alcohol, clearing it in a solvent such as xylene to remove the alcohol, and then impregnating it with melted paraffin wax. The tissue is then cooled and hardened into a block, which can be stored, transported, and sectioned as needed.
Paraffin embedding is a commonly used technique in histology due to its relative simplicity, low cost, and ability to produce high-quality sections for microscopic examination.
Tissue fixation is a process in histology (the study of the microscopic structure of tissues) where fixed tissue samples are prepared for further examination, typically through microscopy. The goal of tissue fixation is to preserve the original three-dimensional structure and biochemical composition of tissues and cells as much as possible, making them stable and suitable for various analyses.
The most common method for tissue fixation involves immersing the sample in a chemical fixative, such as formaldehyde or glutaraldehyde. These fixatives cross-link proteins within the tissue, creating a stable matrix that maintains the original structure and prevents decay. Other methods of tissue fixation may include freezing or embedding samples in various media to preserve their integrity.
Properly fixed tissue samples can be sectioned, stained, and examined under a microscope, allowing pathologists and researchers to study cellular structures, diagnose diseases, and understand biological processes at the molecular level.
Formaldehyde is a colorless, pungent, and volatile chemical compound with the formula CH2O. It is a naturally occurring substance that is found in certain fruits like apples and vegetables, as well as in animals. However, the majority of formaldehyde used in industry is synthetically produced.
In the medical field, formaldehyde is commonly used as a preservative for biological specimens such as organs, tissues, and cells. It works by killing bacteria and inhibiting the decaying process. Formaldehyde is also used in the production of various industrial products, including adhesives, resins, textiles, and paper products.
However, formaldehyde can be harmful to human health if inhaled or ingested in large quantities. It can cause irritation to the eyes, nose, throat, and skin, and prolonged exposure has been linked to respiratory problems and cancer. Therefore, it is essential to handle formaldehyde with care and use appropriate safety measures when working with this chemical compound.
Fixatives are substances used in histology and pathology to preserve tissue specimens for microscopic examination. They work by stabilizing the structural components of cells and tissues, preventing decomposition and autolysis. This helps to maintain the original structure and composition of the specimen as closely as possible, allowing for accurate diagnosis and research. Commonly used fixatives include formalin, glutaraldehyde, methanol, and ethanol. The choice of fixative depends on the specific type of tissue being preserved and the intended use of the specimen.
Immunoenzyme techniques are a group of laboratory methods used in immunology and clinical chemistry that combine the specificity of antibody-antigen reactions with the sensitivity and amplification capabilities of enzyme reactions. These techniques are primarily used for the detection, quantitation, or identification of various analytes (such as proteins, hormones, drugs, viruses, or bacteria) in biological samples.
In immunoenzyme techniques, an enzyme is linked to an antibody or antigen, creating a conjugate. This conjugate then interacts with the target analyte in the sample, forming an immune complex. The presence and amount of this immune complex can be visualized or measured by detecting the enzymatic activity associated with it.
There are several types of immunoenzyme techniques, including:
1. Enzyme-linked Immunosorbent Assay (ELISA): A widely used method for detecting and quantifying various analytes in a sample. In ELISA, an enzyme is attached to either the capture antibody or the detection antibody. After the immune complex formation, a substrate is added that reacts with the enzyme, producing a colored product that can be measured spectrophotometrically.
2. Immunoblotting (Western blot): A method used for detecting specific proteins in a complex mixture, such as a protein extract from cells or tissues. In this technique, proteins are separated by gel electrophoresis and transferred to a membrane, where they are probed with an enzyme-conjugated antibody directed against the target protein.
3. Immunohistochemistry (IHC): A method used for detecting specific antigens in tissue sections or cells. In IHC, an enzyme-conjugated primary or secondary antibody is applied to the sample, and the presence of the antigen is visualized using a chromogenic substrate that produces a colored product at the site of the antigen-antibody interaction.
4. Immunofluorescence (IF): A method used for detecting specific antigens in cells or tissues by employing fluorophore-conjugated antibodies. The presence of the antigen is visualized using a fluorescence microscope.
5. Enzyme-linked immunosorbent assay (ELISA): A method used for detecting and quantifying specific antigens or antibodies in liquid samples, such as serum or culture supernatants. In ELISA, an enzyme-conjugated detection antibody is added after the immune complex formation, and a substrate is added that reacts with the enzyme to produce a colored product that can be measured spectrophotometrically.
These techniques are widely used in research and diagnostic laboratories for various applications, including protein characterization, disease diagnosis, and monitoring treatment responses.
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.
"Frozen sections" is a medical term that refers to the process of quickly preparing and examining a small piece of tissue during surgery. This procedure is typically performed by a pathologist in order to provide immediate diagnostic information to the surgeon, who can then make informed decisions about the course of the operation.
To create a frozen section, the surgical team first removes a small sample of tissue from the patient's body. This sample is then quickly frozen, typically using a special machine that can freeze the tissue in just a few seconds. Once the tissue is frozen, it can be cut into thin slices and stained with dyes to help highlight its cellular structures.
The stained slides are then examined under a microscope by a pathologist, who looks for any abnormalities or signs of disease. The results of this examination are typically available within 10-30 minutes, allowing the surgeon to make real-time decisions about whether to remove more tissue, change the surgical approach, or take other actions based on the findings.
Frozen sections are often used in cancer surgery to help ensure that all of the cancerous tissue has been removed, and to guide decisions about whether additional treatments such as radiation therapy or chemotherapy are necessary. They can also be used in other types of surgeries to help diagnose conditions and make treatment decisions during the procedure.
Microtomy is a medical term that refers to the process of cutting thin slices of tissue for examination under a microscope, typically with the use of a microtome. A microtome is a precision instrument that allows for the uniform and controlled cutting of very thin sections of biological tissues, usually ranging from 2-10 micrometers in thickness.
The process of microtomy involves fixing, embedding, and sectioning the tissue specimen. First, the tissue is fixed using a fixative such as formalin to preserve its structure and prevent decomposition. Then, it is embedded in a support medium, often paraffin wax or a plastic resin, which helps to hold the tissue together during cutting.
Once the tissue is properly prepared, it is loaded into the microtome, where a sharp blade cuts through the tissue, producing thin sections that can be mounted on glass slides and stained with various dyes to highlight specific structures or features of interest. These stained sections are then examined under a microscope for diagnostic or research purposes.
Microtomy is an essential technique in histology, pathology, and many areas of biological research, as it allows researchers and clinicians to visualize the structure and composition of tissues at the cellular and subcellular level.
'Staining and labeling' are techniques commonly used in pathology, histology, cytology, and molecular biology to highlight or identify specific components or structures within tissues, cells, or molecules. These methods enable researchers and medical professionals to visualize and analyze the distribution, localization, and interaction of biological entities, contributing to a better understanding of diseases, cellular processes, and potential therapeutic targets.
Medical definitions for 'staining' and 'labeling' are as follows:
1. Staining: A process that involves applying dyes or stains to tissues, cells, or molecules to enhance their contrast and reveal specific structures or components. Stains can be categorized into basic stains (which highlight acidic structures) and acidic stains (which highlight basic structures). Common staining techniques include Hematoxylin and Eosin (H&E), which differentiates cell nuclei from the surrounding cytoplasm and extracellular matrix; special stains, such as PAS (Periodic Acid-Schiff) for carbohydrates or Masson's trichrome for collagen fibers; and immunostains, which use antibodies to target specific proteins.
2. Labeling: A process that involves attaching a detectable marker or tag to a molecule of interest, allowing its identification, quantification, or tracking within a biological system. Labels can be direct, where the marker is directly conjugated to the targeting molecule, or indirect, where an intermediate linker molecule is used to attach the label to the target. Common labeling techniques include fluorescent labels (such as FITC, TRITC, or Alexa Fluor), enzymatic labels (such as horseradish peroxidase or alkaline phosphatase), and radioactive labels (such as ³²P or ¹⁴C). Labeling is often used in conjunction with staining techniques to enhance the specificity and sensitivity of detection.
Together, staining and labeling provide valuable tools for medical research, diagnostics, and therapeutic development, offering insights into cellular and molecular processes that underlie health and disease.
I'm sorry for any confusion, but "Kerosene" is not a medical term. It is a type of fuel that is commonly used in lamps, stoves, and heating systems. Medically, the term "kerosene sniffing" or "huffing" is used to describe the dangerous practice of inhaling kerosene vapors to get high, which can lead to serious health consequences, including death.
I believe you may be asking for a medical explanation or examples of substances that are referred to as "waxes." Waxes are not a specific medical term, but they can refer to various natural or synthetic esters that are insoluble in water and have a soft, waxy consistency. In a medical context, the term "waxes" might refer to:
1. Cerumen (Earwax): A yellowish waxy substance produced by glands in the ear canal. Cerumen helps protect the ear by trapping dirt, dust, and other particles and preventing them from entering the inner ear.
2. Sebaceous Waxes: These are esters found in sebum, an oily substance produced by sebaceous glands in the skin. Sebum helps keep the skin and hair moisturized and protected.
3. Cutaneous Waxes: These are lipid-rich substances secreted by specialized sweat glands called eccrine glands. They help to waterproof and protect the skin.
4. Histological Waxes: Paraffin or other waxes used in histology for tissue processing, embedding, and microtomy to prepare thin sections of tissues for examination under a microscope.
These are some examples of substances that can be referred to as "waxes" in a medical context.
Tissue preservation is the process of preventing decomposition or autolysis (self-digestion) of tissues after they have been removed from a living organism. This is typically achieved through the use of fixatives, such as formaldehyde or glutaraldehyde, which stabilize proteins and other cellular structures by creating cross-links between them. Other methods of tissue preservation include freezing, dehydration, and embedding in paraffin or plastic resins. Properly preserved tissues can be stored for long periods of time and used for various research and diagnostic purposes, such as histology, immunohistochemistry, and molecular biology studies.
Plastic embedding is a histological technique used in the preparation of tissue samples for microscopic examination. In this process, thin sections of tissue are impregnated and hardened with a plastic resin, which replaces the water in the tissue and provides support and stability during cutting and mounting. This method is particularly useful for tissues that are difficult to embed using traditional paraffin embedding techniques, such as those that contain fat or are very delicate. The plastic-embedded tissue sections can be cut very thinly (typically 1-2 microns) and provide excellent preservation of ultrastructural details, making them ideal for high-resolution microscopy and immunohistochemical studies.
Histocytoлогиcal preparation techniques are methods used to prepare tissue samples for examination under a microscope in order to study the structure and function of cells, specifically histiocytes. These techniques involve fixing, processing, embedding, sectioning, and staining the tissue samples to preserve their cellular details and enhance the visibility of various cellular components.
The process typically begins with fixing the tissue sample in a fixative solution, such as formalin or alcohol, to preserve its structure and prevent decomposition. The fixed tissue is then dehydrated using a series of increasing concentrations of ethanol and cleared with a clearing agent, such as xylene, to remove the ethanol and make the tissue more transparent.
Next, the tissue is infiltrated with a liquid embedding material, such as paraffin or plastic, and solidified into a block. The block is then cut into thin sections using a microtome, and the sections are mounted onto glass slides.
Finally, the sections are stained with various dyes to highlight different cellular components, such as the nucleus, cytoplasm, or specific organelles. Common staining techniques used in histocytoлогиcal preparation include hematoxylin and eosin (H&E), immunohistochemistry (IHC), and special stains for specific cell types or structures.
These techniques allow pathologists to examine the tissue sample at a microscopic level, identify any abnormalities or diseases, and make an accurate diagnosis.
Medical Definition of Mineral Oil:
Mineral oil is a commonly used laxative, which is a substance that promotes bowel movements. It is a non-digestible, odorless, and tasteless oil that is derived from petroleum. When taken orally, mineral oil passes through the digestive system without being absorbed, helping to soften stools and relieve constipation by increasing the weight and size of the stool, stimulating the reflexes in the intestines that trigger bowel movements.
Mineral oil is also used topically as a moisturizer and emollient for dry skin conditions such as eczema and dermatitis. It forms a barrier on the skin, preventing moisture loss and protecting the skin from irritants. However, mineral oil should not be used on broken or inflamed skin, as it can trap bacteria and delay healing.
It is important to note that long-term use of mineral oil laxatives can lead to dependence and may interfere with the absorption of fat-soluble vitamins such as A, D, E, and K. Therefore, it should be used only under the guidance of a healthcare professional.
Tissue embedding is a process in histology (the study of the microscopic structure of tissues) where biological tissue samples are encased in a supporting medium, typically paraffin wax or plastic resins, to maintain their shape and structural integrity during sectioning. This allows for thin slices of the embedded tissue to be cut using a microtome, mounted on slides, and then stained for further examination under a microscope. The embedding process ensures that the tissue remains intact and does not tear or compress during sectioning, providing clear and consistent samples for analysis.
I'm not able to provide a specific medical definition for the term "Decalcification Technique" as it is not a standard term in medical or scientific literature. However, decalcification is a process that is commonly used in histology (the study of the microscopic structure of tissues) to prepare calcium-containing tissue samples for sectioning and staining.
Decalcification involves removing the calcium salts from the tissue using a weak acid solution, such as formic acid or acetic acid. This process makes it possible to cut thin sections of the tissue with a microtome (a tool used to cut thin slices of tissue for examination under a microscope).
The decalcification technique may refer to the specific method or protocol used to decalcify tissue samples, including the type and concentration of acid used, the duration of decalcification, and the temperature at which the process is carried out. The choice of decalcification technique will depend on the type and size of the tissue sample being prepared, as well as the specific research or diagnostic questions being addressed.
Tumor markers are substances that can be found in the body and their presence can indicate the presence of certain types of cancer or other conditions. Biological tumor markers refer to those substances that are produced by cancer cells or by other cells in response to cancer or certain benign (non-cancerous) conditions. These markers can be found in various bodily fluids such as blood, urine, or tissue samples.
Examples of biological tumor markers include:
1. Proteins: Some tumor markers are proteins that are produced by cancer cells or by other cells in response to the presence of cancer. For example, prostate-specific antigen (PSA) is a protein produced by normal prostate cells and in higher amounts by prostate cancer cells.
2. Genetic material: Tumor markers can also include genetic material such as DNA, RNA, or microRNA that are shed by cancer cells into bodily fluids. For example, circulating tumor DNA (ctDNA) is genetic material from cancer cells that can be found in the bloodstream.
3. Metabolites: Tumor markers can also include metabolic products produced by cancer cells or by other cells in response to cancer. For example, lactate dehydrogenase (LDH) is an enzyme that is released into the bloodstream when cancer cells break down glucose for energy.
It's important to note that tumor markers are not specific to cancer and can be elevated in non-cancerous conditions as well. Therefore, they should not be used alone to diagnose cancer but rather as a tool in conjunction with other diagnostic tests and clinical evaluations.
Polymerase Chain Reaction (PCR) is a laboratory technique used to amplify specific regions of DNA. It enables the production of thousands to millions of copies of a particular DNA sequence in a rapid and efficient manner, making it an essential tool in various fields such as molecular biology, medical diagnostics, forensic science, and research.
The PCR process involves repeated cycles of heating and cooling to separate the DNA strands, allow primers (short sequences of single-stranded DNA) to attach to the target regions, and extend these primers using an enzyme called Taq polymerase, resulting in the exponential amplification of the desired DNA segment.
In a medical context, PCR is often used for detecting and quantifying specific pathogens (viruses, bacteria, fungi, or parasites) in clinical samples, identifying genetic mutations or polymorphisms associated with diseases, monitoring disease progression, and evaluating treatment effectiveness.
A biopsy is a medical procedure in which a small sample of tissue is taken from the body to be examined under a microscope for the presence of disease. This can help doctors diagnose and monitor various medical conditions, such as cancer, infections, or autoimmune disorders. The type of biopsy performed will depend on the location and nature of the suspected condition. Some common types of biopsies include:
1. Incisional biopsy: In this procedure, a surgeon removes a piece of tissue from an abnormal area using a scalpel or other surgical instrument. This type of biopsy is often used when the lesion is too large to be removed entirely during the initial biopsy.
2. Excisional biopsy: An excisional biopsy involves removing the entire abnormal area, along with a margin of healthy tissue surrounding it. This technique is typically employed for smaller lesions or when cancer is suspected.
3. Needle biopsy: A needle biopsy uses a thin, hollow needle to extract cells or fluid from the body. There are two main types of needle biopsies: fine-needle aspiration (FNA) and core needle biopsy. FNA extracts loose cells, while a core needle biopsy removes a small piece of tissue.
4. Punch biopsy: In a punch biopsy, a round, sharp tool is used to remove a small cylindrical sample of skin tissue. This type of biopsy is often used for evaluating rashes or other skin abnormalities.
5. Shave biopsy: During a shave biopsy, a thin slice of tissue is removed from the surface of the skin using a sharp razor-like instrument. This technique is typically used for superficial lesions or growths on the skin.
After the biopsy sample has been collected, it is sent to a laboratory where a pathologist will examine the tissue under a microscope and provide a diagnosis based on their findings. The results of the biopsy can help guide further treatment decisions and determine the best course of action for managing the patient's condition.
Hematoxylin is not a medical term per se, but it is widely used in the field of histology and pathology, which are subspecialties within medicine. Hematoxylin is a natural dye that is commonly used in histological staining procedures to highlight cell nuclei in tissue samples. It is often combined with eosin, another dye, to create the well-known hematoxylin and eosin (H&E) stain, which is routinely used to examine tissue architecture and diagnose various medical conditions.
In essence, hematoxylin is a histological stain that selectively binds to the acidic components of nuclear chromatin, imparting a blue-purple color to the cell nuclei when visualized under a microscope. This staining technique helps pathologists and researchers identify and analyze various cellular structures and abnormalities within tissue samples.
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.
The Nucleolus Organizer Region (NOR) is a specific region within the chromosomes, primarily in the short arm of the acrocentric chromosomes (chromosomes 13, 14, 15, 21, and 22). It consists of clusters of repetitive DNA sequences that encode ribosomal RNA (rRNA) genes. During interphase, these regions form the nucleolus, a distinct structure within the nucleus where rRNA transcription, processing, and ribosome assembly occur. The number of NORs in an individual can vary, which has implications in certain genetic conditions and aging processes.
Monoclonal antibodies are a type of antibody that are identical because they are produced by a single clone of cells. They are laboratory-produced molecules that act like human antibodies in the immune system. They can be designed to attach to specific proteins found on the surface of cancer cells, making them useful for targeting and treating cancer. Monoclonal antibodies can also be used as a therapy for other diseases, such as autoimmune disorders and inflammatory conditions.
Monoclonal antibodies are produced by fusing a single type of immune cell, called a B cell, with a tumor cell to create a hybrid cell, or hybridoma. This hybrid cell is then able to replicate indefinitely, producing a large number of identical copies of the original antibody. These antibodies can be further modified and engineered to enhance their ability to bind to specific targets, increase their stability, and improve their effectiveness as therapeutic agents.
Monoclonal antibodies have several mechanisms of action in cancer therapy. They can directly kill cancer cells by binding to them and triggering an immune response. They can also block the signals that promote cancer growth and survival. Additionally, monoclonal antibodies can be used to deliver drugs or radiation directly to cancer cells, increasing the effectiveness of these treatments while minimizing their side effects on healthy tissues.
Monoclonal antibodies have become an important tool in modern medicine, with several approved for use in cancer therapy and other diseases. They are continuing to be studied and developed as a promising approach to treating a wide range of medical conditions.
I'm sorry for any confusion, but "Lipid Pneumonia" is not a type of pneumonia that is defined by the presence of lipids in the lungs. Instead, it refers to a condition where an abnormal amount of lipids or fatty substances accumulate in the lung tissue, which can lead to inflammation and infection, resulting in pneumonia.
Lipid pneumonia can occur due to various reasons, such as aspiration of lipid-containing materials (like oil-based nasal drops, mineral oil, or contaminated food), impaired lipid metabolism, or lung damage from certain medical conditions or treatments. The accumulation of these fatty substances in the lungs can cause an inflammatory response, leading to symptoms similar to those seen in other types of pneumonia, such as cough, fever, chest pain, and difficulty breathing.
Therefore, lipid pneumonia is not a medical definition per se but rather a term used to describe a condition where lipids accumulate in the lungs and cause inflammation and infection.
In the context of medicine and pharmacology, oils are typically defined as lipid-based substances that are derived from plants or animals. They are made up of molecules called fatty acids, which can be either saturated or unsaturated. Oils are often used in medical treatments and therapies due to their ability to deliver active ingredients through the skin, as well as their moisturizing and soothing properties. Some oils, such as essential oils, are also used in aromatherapy for their potential therapeutic benefits. However, it's important to note that some oils can be toxic or irritating if ingested or applied to the skin in large amounts, so they should always be used with caution and under the guidance of a healthcare professional.
The term "DNA, neoplasm" is not a standard medical term or concept. DNA refers to deoxyribonucleic acid, which is the genetic material present in the cells of living organisms. A neoplasm, on the other hand, is a tumor or growth of abnormal tissue that can be benign (non-cancerous) or malignant (cancerous).
In some contexts, "DNA, neoplasm" may refer to genetic alterations found in cancer cells. These genetic changes can include mutations, amplifications, deletions, or rearrangements of DNA sequences that contribute to the development and progression of cancer. Identifying these genetic abnormalities can help doctors diagnose and treat certain types of cancer more effectively.
However, it's important to note that "DNA, neoplasm" is not a term that would typically be used in medical reports or research papers without further clarification. If you have any specific questions about DNA changes in cancer cells or neoplasms, I would recommend consulting with a healthcare professional or conducting further research on the topic.
The Ki-67 antigen is a cellular protein that is expressed in all active phases of the cell cycle (G1, S, G2, and M), but not in the resting phase (G0). It is often used as a marker for cell proliferation and can be found in high concentrations in rapidly dividing cells. Immunohistochemical staining for Ki-67 can help to determine the growth fraction of a group of cells, which can be useful in the diagnosis and prognosis of various malignancies, including cancer. The level of Ki-67 expression is often associated with the aggressiveness of the tumor and its response to treatment.
Histochemistry is the branch of pathology that deals with the microscopic localization of cellular or tissue components using specific chemical reactions. It involves the application of chemical techniques to identify and locate specific biomolecules within tissues, cells, and subcellular structures. This is achieved through the use of various staining methods that react with specific antigens or enzymes in the sample, allowing for their visualization under a microscope. Histochemistry is widely used in diagnostic pathology to identify different types of tissues, cells, and structures, as well as in research to study cellular and molecular processes in health and disease.
A neoplasm is a tumor or growth that is formed by an abnormal and excessive proliferation of cells, which can be benign or malignant. Neoplasm proteins are therefore any proteins that are expressed or produced in these neoplastic cells. These proteins can play various roles in the development, progression, and maintenance of neoplasms.
Some neoplasm proteins may contribute to the uncontrolled cell growth and division seen in cancer, such as oncogenic proteins that promote cell cycle progression or inhibit apoptosis (programmed cell death). Others may help the neoplastic cells evade the immune system, allowing them to proliferate undetected. Still others may be involved in angiogenesis, the formation of new blood vessels that supply the tumor with nutrients and oxygen.
Neoplasm proteins can also serve as biomarkers for cancer diagnosis, prognosis, or treatment response. For example, the presence or level of certain neoplasm proteins in biological samples such as blood or tissue may indicate the presence of a specific type of cancer, help predict the likelihood of cancer recurrence, or suggest whether a particular therapy will be effective.
Overall, understanding the roles and behaviors of neoplasm proteins can provide valuable insights into the biology of cancer and inform the development of new diagnostic and therapeutic strategies.
The palatine tonsils, also known as the "tonsils," are two masses of lymphoid tissue located on either side of the oropharynx, at the back of the throat. They are part of the immune system and play a role in protecting the body from inhaled or ingested pathogens. Each tonsil has a surface covered with crypts and follicles that contain lymphocytes, which help to filter out bacteria and viruses that enter the mouth and nose.
The palatine tonsils are visible through the mouth and can be seen during a routine physical examination. They vary in size, but typically are about the size of a large olive or almond. Swelling or inflammation of the tonsils is called tonsillitis, which can cause symptoms such as sore throat, difficulty swallowing, fever, and swollen lymph nodes in the neck. In some cases, enlarged tonsils may need to be removed through a surgical procedure called a tonsillectomy.
Breast neoplasms refer to abnormal growths in the breast tissue that can be benign or malignant. Benign breast neoplasms are non-cancerous tumors or growths, while malignant breast neoplasms are cancerous tumors that can invade surrounding tissues and spread to other parts of the body.
Breast neoplasms can arise from different types of cells in the breast, including milk ducts, milk sacs (lobules), or connective tissue. The most common type of breast cancer is ductal carcinoma, which starts in the milk ducts and can spread to other parts of the breast and nearby structures.
Breast neoplasms are usually detected through screening methods such as mammography, ultrasound, or MRI, or through self-examination or clinical examination. Treatment options for breast neoplasms depend on several factors, including the type and stage of the tumor, the patient's age and overall health, and personal preferences. Treatment may include surgery, radiation therapy, chemotherapy, hormone therapy, or targeted therapy.
Molecular pathology is a branch of pathology that involves the study and diagnosis of diseases at the molecular level. It utilizes various molecular biology techniques such as DNA sequencing, polymerase chain reaction (PCR), and others to identify genetic mutations, gene expression changes, and protein abnormalities that underlie various diseases including cancer, genetic disorders, infectious diseases, and autoimmune conditions. The information obtained from molecular testing can help guide clinical decision-making, inform prognosis, and monitor response to therapy. Additionally, molecular pathology plays a critical role in the development of personalized medicine, which tailors treatment strategies based on an individual's unique genetic makeup and disease characteristics.
"Silver staining" is a histological term that refers to a technique used to selectively stain various components of biological tissues, making them more visible under a microscope. This technique is often used in the study of histopathology and cytology. The most common type of silver staining is known as "silver impregnation," which is used to demonstrate the presence of argyrophilic structures, such as nerve fibers and neurofibrillary tangles, in tissues.
The process of silver staining involves the use of silver salts, which are reduced by a developer to form metallic silver that deposits on the tissue components. The intensity of the stain depends on the degree of reduction of the silver ions, and it can be modified by adjusting the concentration of the silver salt, the development time, and other factors.
Silver staining is widely used in diagnostic pathology to highlight various structures such as nerve fibers, axons, collagen, basement membranes, and microorganisms like fungi and bacteria. It has also been used in research to study the distribution and organization of these structures in tissues. However, it's important to note that silver staining is not specific for any particular substance, so additional tests are often needed to confirm the identity of the stained structures.
Adenocarcinoma is a type of cancer that arises from glandular epithelial cells. These cells line the inside of many internal organs, including the breasts, prostate, colon, and lungs. Adenocarcinomas can occur in any of these organs, as well as in other locations where glands are present.
The term "adenocarcinoma" is used to describe a cancer that has features of glandular tissue, such as mucus-secreting cells or cells that produce hormones. These cancers often form glandular structures within the tumor mass and may produce mucus or other substances.
Adenocarcinomas are typically slow-growing and tend to spread (metastasize) to other parts of the body through the lymphatic system or bloodstream. They can be treated with surgery, radiation therapy, chemotherapy, targeted therapy, or a combination of these treatments. The prognosis for adenocarcinoma depends on several factors, including the location and stage of the cancer, as well as the patient's overall health and age.
Ploidy is a term used in genetics to describe the number of sets of chromosomes in a cell or an organism. The ploidy level can have important implications for genetic inheritance and expression, as well as for evolutionary processes such as speciation and hybridization.
In most animals, including humans, the normal ploidy level is diploid, meaning that each cell contains two sets of chromosomes - one set inherited from each parent. However, there are also many examples of polyploidy, in which an organism has more than two sets of chromosomes.
Polyploidy can arise through various mechanisms, such as genome duplication or hybridization between different species. In some cases, polyploidy may confer evolutionary advantages, such as increased genetic diversity and adaptability to new environments. However, it can also lead to reproductive isolation and the formation of new species.
In plants, polyploidy is relatively common and has played a significant role in their evolution and diversification. Many crop plants are polyploids, including wheat, cotton, and tobacco. In some cases, artificial induction of polyploidy has been used to create new varieties with desirable traits for agriculture and horticulture.
Overall, ploidy is an important concept in genetics and evolution, with implications for a wide range of biological processes and phenomena.
In situ hybridization, fluorescence (FISH) is a type of molecular cytogenetic technique used to detect and localize the presence or absence of specific DNA sequences on chromosomes through the use of fluorescent probes. This technique allows for the direct visualization of genetic material at a cellular level, making it possible to identify chromosomal abnormalities such as deletions, duplications, translocations, and other rearrangements.
The process involves denaturing the DNA in the sample to separate the double-stranded molecules into single strands, then adding fluorescently labeled probes that are complementary to the target DNA sequence. The probe hybridizes to the complementary sequence in the sample, and the location of the probe is detected by fluorescence microscopy.
FISH has a wide range of applications in both clinical and research settings, including prenatal diagnosis, cancer diagnosis and monitoring, and the study of gene expression and regulation. It is a powerful tool for identifying genetic abnormalities and understanding their role in human disease.
Tissue Microarray (TMA) analysis is a surgical pathology technique that allows for the simultaneous analysis of multiple tissue samples (known as "cores") from different patients or even different regions of the same tumor, on a single microscope slide. This technique involves the extraction of small cylindrical samples of tissue, which are then arrayed in a grid-like pattern on a recipient paraffin block. Once the TMA is created, sections can be cut and stained with various histochemical or immunohistochemical stains to evaluate the expression of specific proteins or other molecules of interest.
Tissue Array Analysis has become an important tool in biomedical research, enabling high-throughput analysis of tissue samples for molecular markers, gene expression patterns, and other features that can help inform clinical decision making, drug development, and our understanding of disease processes. It's widely used in cancer research to study the heterogeneity of tumors, identify new therapeutic targets, and evaluate patient prognosis.
Prognosis is a medical term that refers to the prediction of the likely outcome or course of a disease, including the chances of recovery or recurrence, based on the patient's symptoms, medical history, physical examination, and diagnostic tests. It is an important aspect of clinical decision-making and patient communication, as it helps doctors and patients make informed decisions about treatment options, set realistic expectations, and plan for future care.
Prognosis can be expressed in various ways, such as percentages, categories (e.g., good, fair, poor), or survival rates, depending on the nature of the disease and the available evidence. However, it is important to note that prognosis is not an exact science and may vary depending on individual factors, such as age, overall health status, and response to treatment. Therefore, it should be used as a guide rather than a definitive forecast.
A Tissue Bank is a specialized facility that collects, stores, and distributes human tissues for medical research, transplantation, or therapeutic purposes. These tissues can include organs, bones, skin, heart valves, tendons, and other bodily tissues that can be used for various medical applications.
Tissue banks follow strict regulations and guidelines to ensure the safety and quality of the tissues they handle. They implement rigorous screening and testing procedures to minimize the risk of disease transmission and maintain the integrity of the tissues. The tissues are stored under specific conditions, such as temperature and humidity, to preserve their function and viability until they are needed for use.
Tissue banks play a critical role in advancing medical research and improving patient outcomes by providing researchers and clinicians with access to high-quality human tissues for study and transplantation.
Neoplasm antigens, also known as tumor antigens, are substances that are produced by cancer cells (neoplasms) and can stimulate an immune response. These antigens can be proteins, carbohydrates, or other molecules that are either unique to the cancer cells or are overexpressed or mutated versions of normal cellular proteins.
Neoplasm antigens can be classified into two main categories: tumor-specific antigens (TSAs) and tumor-associated antigens (TAAs). TSAs are unique to cancer cells and are not expressed by normal cells, while TAAs are present at low levels in normal cells but are overexpressed or altered in cancer cells.
TSAs can be further divided into viral antigens and mutated antigens. Viral antigens are produced when cancer is caused by a virus, such as human papillomavirus (HPV) in cervical cancer. Mutated antigens are the result of genetic mutations that occur during cancer development and are unique to each patient's tumor.
Neoplasm antigens play an important role in the immune response against cancer. They can be recognized by the immune system, leading to the activation of immune cells such as T cells and natural killer (NK) cells, which can then attack and destroy cancer cells. However, cancer cells often develop mechanisms to evade the immune response, allowing them to continue growing and spreading.
Understanding neoplasm antigens is important for the development of cancer immunotherapies, which aim to enhance the body's natural immune response against cancer. These therapies include checkpoint inhibitors, which block proteins that inhibit T cell activation, and therapeutic vaccines, which stimulate an immune response against specific tumor antigens.
Proliferating Cell Nuclear Antigen (PCNA) is a protein that plays an essential role in the process of DNA replication and repair in eukaryotic cells. It functions as a cofactor for DNA polymerase delta, enhancing its activity during DNA synthesis. PCNA forms a sliding clamp around DNA, allowing it to move along the template and coordinate the actions of various enzymes involved in DNA metabolism.
PCNA is often used as a marker for cell proliferation because its levels increase in cells that are actively dividing or have been stimulated to enter the cell cycle. Immunostaining techniques can be used to detect PCNA and determine the proliferative status of tissues or cultures. In this context, 'proliferating' refers to the rapid multiplication of cells through cell division.
I'm sorry for any confusion, but "microwaves" is not a term typically used in medical definitions. Microwaves are a form of electromagnetic radiation with wavelengths ranging from one meter to one millimeter; they are commonly used in communication devices and home appliances such as microwave ovens. If you have any questions related to health or medicine, please provide more context so I can give you a more accurate response.
Adenofibroma is a rare, benign tumor that occurs most commonly in the salivary glands. It is composed of both glandular tissue (adeno-) and fibrous tissue (-fibroma). These tumors are slow-growing and typically do not spread to other parts of the body.
Adenofibromas can also occur in other areas of the body, such as the skin, where they may be referred to as "fibroepithelial polyps" or "skin tags." In general, adenofibromas are not cancerous and can often be removed surgically. However, it is important to have any new growths or lumps evaluated by a healthcare professional to determine the appropriate course of treatment.
Sensitivity and specificity are statistical measures used to describe the performance of a diagnostic test or screening tool in identifying true positive and true negative results.
* Sensitivity refers to the proportion of people who have a particular condition (true positives) who are correctly identified by the test. It is also known as the "true positive rate" or "recall." A highly sensitive test will identify most or all of the people with the condition, but may also produce more false positives.
* Specificity refers to the proportion of people who do not have a particular condition (true negatives) who are correctly identified by the test. It is also known as the "true negative rate." A highly specific test will identify most or all of the people without the condition, but may also produce more false negatives.
In medical testing, both sensitivity and specificity are important considerations when evaluating a diagnostic test. High sensitivity is desirable for screening tests that aim to identify as many cases of a condition as possible, while high specificity is desirable for confirmatory tests that aim to rule out the condition in people who do not have it.
It's worth noting that sensitivity and specificity are often influenced by factors such as the prevalence of the condition in the population being tested, the threshold used to define a positive result, and the reliability and validity of the test itself. Therefore, it's important to consider these factors when interpreting the results of a diagnostic test.
Squamous cell carcinoma is a type of skin cancer that begins in the squamous cells, which are flat, thin cells that form the outer layer of the skin (epidermis). It commonly occurs on sun-exposed areas such as the face, ears, lips, and backs of the hands. Squamous cell carcinoma can also develop in other areas of the body including the mouth, lungs, and cervix.
This type of cancer usually develops slowly and may appear as a rough or scaly patch of skin, a red, firm nodule, or a sore or ulcer that doesn't heal. While squamous cell carcinoma is not as aggressive as some other types of cancer, it can metastasize (spread) to other parts of the body if left untreated, making early detection and treatment important.
Risk factors for developing squamous cell carcinoma include prolonged exposure to ultraviolet (UV) radiation from the sun or tanning beds, fair skin, a history of sunburns, a weakened immune system, and older age. Prevention measures include protecting your skin from the sun by wearing protective clothing, using a broad-spectrum sunscreen with an SPF of at least 30, avoiding tanning beds, and getting regular skin examinations.
Lymph nodes are small, bean-shaped organs that are part of the immune system. They are found throughout the body, especially in the neck, armpits, groin, and abdomen. Lymph nodes filter lymph fluid, which carries waste and unwanted substances such as bacteria, viruses, and cancer cells. They contain white blood cells called lymphocytes that help fight infections and diseases by attacking and destroying the harmful substances found in the lymph fluid. When an infection or disease is present, lymph nodes may swell due to the increased number of immune cells and fluid accumulation as they work to fight off the invaders.
Digoxigenin is a steroidal glycoside compound that is derived from the digitalis plant, which includes foxglove species. This compound is known for its cardiotonic properties and has been used in the treatment of various heart conditions, such as congestive heart failure and atrial arrhythmias.
In a medical or scientific context, digoxigenin is often used in research and diagnostic applications due to its ability to bind to specific antibodies or other molecules. This binding property makes it useful for techniques like immunohistochemistry, where it can be used to label and visualize specific proteins or structures within cells or tissues.
It's important to note that digoxigenin itself is not a medication or treatment, but rather a component derived from a plant that has been used in the development of certain medications and research tools.
The Periodic Acid-Schiff (PAS) reaction is a histological staining method used to detect the presence of certain carbohydrates, such as glycogen and glycoproteins, in tissues or cells. This technique involves treating the tissue with periodic acid, which oxidizes the vicinal hydroxyl groups in the carbohydrates, creating aldehydes. The aldehydes then react with Schiff's reagent, forming a magenta-colored complex that is visible under a microscope.
The PAS reaction is commonly used to identify and analyze various tissue components, such as basement membranes, fungal cell walls, and mucins in the respiratory and gastrointestinal tracts. It can also be used to diagnose certain medical conditions, like kidney diseases, where abnormal accumulations of carbohydrates occur in the renal tubules or glomeruli.
In summary, the Periodic Acid-Schiff reaction is a staining method that detects specific carbohydrates in tissues or cells, which can aid in diagnostic and research applications.
Retrospective studies, also known as retrospective research or looking back studies, are a type of observational study that examines data from the past to draw conclusions about possible causal relationships between risk factors and outcomes. In these studies, researchers analyze existing records, medical charts, or previously collected data to test a hypothesis or answer a specific research question.
Retrospective studies can be useful for generating hypotheses and identifying trends, but they have limitations compared to prospective studies, which follow participants forward in time from exposure to outcome. Retrospective studies are subject to biases such as recall bias, selection bias, and information bias, which can affect the validity of the results. Therefore, retrospective studies should be interpreted with caution and used primarily to generate hypotheses for further testing in prospective studies.
An emulsion is a type of stable mixture of two immiscible liquids, such as oil and water, which are normally unable to mix together uniformly. In an emulsion, one liquid (the dispersed phase) is broken down into small droplets and distributed throughout the other liquid (the continuous phase), creating a stable, cloudy mixture.
In medical terms, emulsions can be used in various pharmaceutical and cosmetic applications. For example, certain medications may be formulated as oil-in-water or water-in-oil emulsions to improve their absorption, stability, or palatability. Similarly, some skincare products and makeup removers contain emulsifiers that help create stable mixtures of water and oils, allowing for effective cleansing and moisturizing.
Emulsions can also occur naturally in the body, such as in the digestion of fats. The bile salts produced by the liver help to form small droplets of dietary lipids (oil) within the watery environment of the small intestine, allowing for efficient absorption and metabolism of these nutrients.
Diathermy is a medical term that refers to the use of high-frequency electrical currents to heat body tissues. The term "diathermy" comes from the Greek words "dia," meaning "through," and "therme," meaning "heat." There are several types of diathermy, including shortwave, microwave, and ultrasound diathermy.
Shortwave diathermy uses electromagnetic waves with frequencies between 10 MHz and 27 MHz to generate heat in deep tissues. This type of diathermy is often used to treat muscle or joint pain, increase blood flow, or promote healing after surgery or injury.
Microwave diathermy uses high-frequency electromagnetic waves with frequencies between 915 MHz and 2450 MHz to generate heat in superficial tissues. This type of diathermy is often used to treat skin conditions such as dermatitis or psoriasis.
Ultrasound diathermy uses high-frequency sound waves with frequencies above 1 MHz to generate heat in soft tissues. This type of diathermy is often used to treat muscle or tendon injuries, promote healing, or relieve pain.
Diathermy should be administered by a trained healthcare professional, as there are potential risks and complications associated with its use, including burns, discomfort, or damage to implanted medical devices such as pacemakers.
Histology is the study of the microscopic structure of tissues. It involves the examination of tissues at the level of individual cells and their organization into functional units. This field uses various staining techniques to visualize different cellular components, allowing for the identification and analysis of specific cell types, tissue architecture, and pathological changes. Histology is a fundamental discipline in anatomy, physiology, and pathology, providing essential information for understanding normal tissue function and disease processes.
DNA probes for HPV (Human Papillomavirus) are specific DNA sequences that are used in diagnostic tests to detect and identify the presence of HPV DNA in a sample. HPV is a viral infection that can cause various types of cancer, including cervical, anal, and oropharyngeal cancers.
DNA probes for HPV work by binding to complementary sequences of HPV DNA in the sample. This binding can be detected and measured using various methods, such as hybridization, amplification, or labeling techniques. The use of DNA probes for HPV can help identify the specific type of HPV that is present in a sample, which can inform clinical management and treatment decisions.
It's important to note that not all HPV infections lead to cancer, and most HPV infections resolve on their own without causing any harm. However, certain high-risk types of HPV are more strongly associated with an increased risk of developing cancer, so identifying the presence and type of HPV infection can be useful for monitoring and managing patients who may be at higher risk.
Estrogen receptors (ERs) are a type of nuclear receptor protein that are expressed in various tissues and cells throughout the body. They play a critical role in the regulation of gene expression and cellular responses to the hormone estrogen. There are two main subtypes of ERs, ERα and ERβ, which have distinct molecular structures, expression patterns, and functions.
ERs function as transcription factors that bind to specific DNA sequences called estrogen response elements (EREs) in the promoter regions of target genes. When estrogen binds to the ER, it causes a conformational change in the receptor that allows it to recruit co-activator proteins and initiate transcription of the target gene. This process can lead to a variety of cellular responses, including changes in cell growth, differentiation, and metabolism.
Estrogen receptors are involved in a wide range of physiological processes, including the development and maintenance of female reproductive tissues, bone homeostasis, cardiovascular function, and cognitive function. They have also been implicated in various pathological conditions, such as breast cancer, endometrial cancer, and osteoporosis. As a result, ERs are an important target for therapeutic interventions in these diseases.
Keratins are a type of fibrous structural proteins that constitute the main component of the integumentary system, which includes the hair, nails, and skin of vertebrates. They are also found in other tissues such as horns, hooves, feathers, and reptilian scales. Keratins are insoluble proteins that provide strength, rigidity, and protection to these structures.
Keratins are classified into two types: soft keratins (Type I) and hard keratins (Type II). Soft keratins are found in the skin and simple epithelial tissues, while hard keratins are present in structures like hair, nails, horns, and hooves.
Keratin proteins have a complex structure consisting of several domains, including an alpha-helical domain, beta-pleated sheet domain, and a non-repetitive domain. These domains provide keratin with its unique properties, such as resistance to heat, chemicals, and mechanical stress.
In summary, keratins are fibrous structural proteins that play a crucial role in providing strength, rigidity, and protection to various tissues in the body.
Keratin-13 is a type of keratin protein that is primarily found in the differentiated suprabasal layers of the epithelial tissues, including the oral mucosa and the esophageal mucosa. It is a component of the intermediate filament cytoskeleton of the epithelial cells and plays an important role in maintaining the structural integrity and function of these tissues.
Mutations in the gene that encodes keratin-13 have been associated with several inherited skin disorders, including epidermolysis bullosa simplex, a group of blistering diseases characterized by fragility of the skin and mucous membranes. These mutations can lead to abnormalities in the structure and stability of keratin-13, resulting in the formation of blisters and sores in response to minor trauma or friction.
T-cell lymphoma is a type of cancer that affects the T-cells, which are a specific type of white blood cell responsible for immune function. These lymphomas develop from mature T-cells and can be classified into various subtypes based on their clinical and pathological features.
T-cell lymphomas can arise in many different organs, including the lymph nodes, skin, and other soft tissues. They often present with symptoms such as enlarged lymph nodes, fever, night sweats, and weight loss. The diagnosis of T-cell lymphoma typically involves a biopsy of the affected tissue, followed by immunophenotyping and genetic analysis to determine the specific subtype.
Treatment for T-cell lymphomas may include chemotherapy, radiation therapy, immunotherapy, or stem cell transplantation, depending on the stage and aggressiveness of the disease. The prognosis for T-cell lymphoma varies widely depending on the subtype and individual patient factors.
Carcinoma, ductal, breast is a type of breast cancer that begins in the milk ducts (the tubes that carry milk from the lobules of the breast to the nipple). It is called "ductal" because it starts in the cells that line the milk ducts. Ductal carcinoma can be further classified as either non-invasive or invasive, based on whether the cancer cells are confined to the ducts or have spread beyond them into the surrounding breast tissue.
Non-invasive ductal carcinoma (also known as intraductal carcinoma or ductal carcinoma in situ) is a condition where abnormal cells have been found in the lining of the milk ducts, but they have not spread outside of the ducts. These cells have the potential to become invasive and spread to other parts of the breast or body if left untreated.
Invasive ductal carcinoma (IDC) is a type of breast cancer that starts in a milk duct and then grows into the surrounding breast tissue. From there, it can spread to other parts of the body through the bloodstream and lymphatic system. IDC is the most common form of breast cancer, accounting for about 80% of all cases.
Symptoms of ductal carcinoma may include a lump or thickening in the breast, changes in the size or shape of the breast, dimpling or puckering of the skin on the breast, nipple discharge (especially if it is clear or bloody), and/or redness or scaling of the nipple or breast skin. However, many cases of ductal carcinoma are detected through mammography before any symptoms develop.
Treatment for ductal carcinoma depends on several factors, including the stage and grade of the cancer, as well as the patient's overall health and personal preferences. Treatment options may include surgery (such as a lumpectomy or mastectomy), radiation therapy, chemotherapy, hormone therapy, and/or targeted therapies.