Polyvinyl Chloride: A polyvinyl resin used extensively in the manufacture of plastics, including medical devices, tubing, and other packaging. It is also used as a rubber substitute.Exosomes: A type of extracellular vesicle, containing RNA and proteins, that is secreted into the extracellular space by EXOCYTOSIS when MULTIVESICULAR BODIES fuse with the PLASMA MEMBRANE.Feeder Cells: Cells used in COCULTURE TECHNIQUES which support the growth of the other cells in the culture. Feeder cells provide auxillary substances including attachment substrates, nutrients, or other factors that are needed for growth in culture.Pluripotent Stem Cells: Cells that can give rise to cells of the three different GERM LAYERS.Cell-Derived Microparticles: Extracellular vesicles generated by the shedding of CELL MEMBRANE blebs.Induced Pluripotent Stem Cells: Cells from adult organisms that have been reprogrammed into a pluripotential state similar to that of EMBRYONIC STEM CELLS.Hydrogels: Water swollen, rigid, 3-dimensional network of cross-linked, hydrophilic macromolecules, 20-95% water. They are used in paints, printing inks, foodstuffs, pharmaceuticals, and cosmetics. (Grant & Hackh's Chemical Dictionary, 5th ed)Kallikreins: Proteolytic enzymes from the serine endopeptidase family found in normal blood and urine. Specifically, Kallikreins are potent vasodilators and hypotensives and increase vascular permeability and affect smooth muscle. They act as infertility agents in men. Three forms are recognized, PLASMA KALLIKREIN (EC, TISSUE KALLIKREIN (EC, and PROSTATE-SPECIFIC ANTIGEN (EC Excision of one or both adrenal glands. (From Dorland, 28th ed)Kinins: A generic term used to describe a group of polypeptides with related chemical structures and pharmacological properties that are widely distributed in nature. These peptides are AUTACOIDS that act locally to produce pain, vasodilatation, increased vascular permeability, and the synthesis of prostaglandins. Thus, they comprise a subset of the large number of mediators that contribute to the inflammatory response. (From Goodman and Gilman's The Pharmacologic Basis of Therapeutics, 8th ed, p588)Aldosterone: A hormone secreted by the ADRENAL CORTEX that regulates electrolyte and water balance by increasing the renal retention of sodium and the excretion of potassium.Extracellular Space: Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.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.Ileum: The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.Hypovolemia: An abnormally low volume of blood circulating through the body. It may result in hypovolemic shock (see SHOCK).Upper Gastrointestinal Tract: The segment of GASTROINTESTINAL TRACT that includes the ESOPHAGUS; the STOMACH; and the DUODENUM.Colon: The segment of LARGE INTESTINE between the CECUM and the RECTUM. It includes the ASCENDING COLON; the TRANSVERSE COLON; the DESCENDING COLON; and the SIGMOID COLON.Blood Volume: Volume of circulating BLOOD. It is the sum of the PLASMA VOLUME and ERYTHROCYTE VOLUME.Crohn Disease: A chronic transmural inflammation that may involve any part of the DIGESTIVE TRACT from MOUTH to ANUS, mostly found in the ILEUM, the CECUM, and the COLON. In Crohn disease, the inflammation, extending through the intestinal wall from the MUCOSA to the serosa, is characteristically asymmetric and segmental. Epithelioid GRANULOMAS may be seen in some patients.Hepatorenal Syndrome: Functional KIDNEY FAILURE in patients with liver disease, usually LIVER CIRRHOSIS or portal hypertension (HYPERTENSION, PORTAL), and in the absence of intrinsic renal disease or kidney abnormality. It is characterized by intense renal vasculature constriction, reduced renal blood flow, OLIGURIA, and sodium retention.Hyponatremia: Deficiency of sodium in the blood; salt depletion. (Dorland, 27th ed)Ascites: Accumulation or retention of free fluid within the peritoneal cavity.Peritonitis: INFLAMMATION of the PERITONEUM lining the ABDOMINAL CAVITY as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the PERITONEAL CAVITY via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the ABDOMINAL CAVITY itself through RUPTURE or ABSCESS of intra-abdominal organs.Hepatic Encephalopathy: A syndrome characterized by central nervous system dysfunction in association with LIVER FAILURE, including portal-systemic shunts. Clinical features include lethargy and CONFUSION (frequently progressing to COMA); ASTERIXIS; NYSTAGMUS, PATHOLOGIC; brisk oculovestibular reflexes; decorticate and decerebrate posturing; MUSCLE SPASTICITY; and bilateral extensor plantar reflexes (see REFLEX, BABINSKI). ELECTROENCEPHALOGRAPHY may demonstrate triphasic waves. (From Adams et al., Principles of Neurology, 6th ed, pp1117-20; Plum & Posner, Diagnosis of Stupor and Coma, 3rd ed, p222-5)Liver Cirrhosis: Liver disease in which the normal microcirculation, the gross vascular anatomy, and the hepatic architecture have been variably destroyed and altered with fibrous septa surrounding regenerated or regenerating parenchymal nodules.Lypressin: The porcine antidiuretic hormone (VASOPRESSINS). It is a cyclic nonapeptide that differs from ARG-VASOPRESSIN by one amino acid, containing a LYSINE at residue 8 instead of an ARGININE. Lys-vasopressin is used to treat DIABETES INSIPIDUS or to improve vasomotor tone and BLOOD PRESSURE.Zidovudine: A dideoxynucleoside compound in which the 3'-hydroxy group on the sugar moiety has been replaced by an azido group. This modification prevents the formation of phosphodiester linkages which are needed for the completion of nucleic acid chains. The compound is a potent inhibitor of HIV replication, acting as a chain-terminator of viral DNA during reverse transcription. It improves immunologic function, partially reverses the HIV-induced neurological dysfunction, and improves certain other clinical abnormalities associated with AIDS. Its principal toxic effect is dose-dependent suppression of bone marrow, resulting in anemia and leukopenia.Microdialysis: A technique for measuring extracellular concentrations of substances in tissues, usually in vivo, by means of a small probe equipped with a semipermeable membrane. Substances may also be introduced into the extracellular space through the membrane.Macaca mulatta: A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.Anti-HIV Agents: Agents used to treat AIDS and/or stop the spread of the HIV infection. These do not include drugs used to treat symptoms or opportunistic infections associated with AIDS.Actinomycetaceae: A family of bacteria including numerous parasitic and pathogenic forms.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Half-Life: The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity.Oxidative Stress: A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).Stress, Mechanical: A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.Hyaluronic Acid: A natural high-viscosity mucopolysaccharide with alternating beta (1-3) glucuronide and beta (1-4) glucosaminidic bonds. It is found in the UMBILICAL CORD, in VITREOUS BODY and in SYNOVIAL FLUID. A high urinary level is found in PROGERIA.Disease Progression: The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.Tumor Microenvironment: The milieu surrounding neoplasms consisting of cells, vessels, soluble factors, and molecules, that can influence and be influenced by, the neoplasm's growth.Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.Cell Line, Tumor: A cell line derived from cultured tumor cells.Disseminated Intravascular Coagulation: A disorder characterized by procoagulant substances entering the general circulation causing a systemic thrombotic process. The activation of the clotting mechanism may arise from any of a number of disorders. A majority of the patients manifest skin lesions, sometimes leading to PURPURA FULMINANS.Lung Diseases, Interstitial: A diverse group of lung diseases that affect the lung parenchyma. They are characterized by an initial inflammation of PULMONARY ALVEOLI that extends to the interstitium and beyond leading to diffuse PULMONARY FIBROSIS. Interstitial lung diseases are classified by their etiology (known or unknown causes), and radiological-pathological features.Hand: The distal part of the arm beyond the wrist in humans and primates, that includes the palm, fingers, and thumb.Ultrasonography, Interventional: The use of ultrasound to guide minimally invasive surgical procedures such as needle ASPIRATION BIOPSY; DRAINAGE; etc. Its widest application is intravascular ultrasound imaging but it is useful also in urology and intra-abdominal conditions.Transcellular Cell Migration: The movement of one cell into, through, and out of another cell.Biological Transport: The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.Leukotriene A4: (2S-(2 alpha,3 beta(1E,3E,5Z,8Z)))-3-(1,3,5,8-Tetradecatetraenyl)oxiranebutanoic acid. An unstable allylic epoxide, formed from the immediate precursor 5-HPETE via the stereospecific removal of a proton at C-10 and dehydration. Its biological actions are determined primarily by its metabolites, i.e., LEUKOTRIENE B4 and cysteinyl-leukotrienes. Alternatively, leukotriene A4 is converted into LEUKOTRIENE C4 by glutathione-S-transferase or into 5,6-di-HETE by the epoxide-hydrolase. (From Dictionary of Prostaglandins and Related Compounds, 1990)Body Fluid Compartments: The two types of spaces between which water and other body fluids are distributed: extracellular and intracellular.Body Water: Fluids composed mainly of water found within the body.Body Fluids: Liquid components of living organisms.Aortopulmonary Septal Defect: A developmental abnormality in which the spiral (aortopulmonary) septum failed to completely divide the TRUNCUS ARTERIOSUS into ASCENDING AORTA and PULMONARY ARTERY. This abnormal communication between the two major vessels usually lies above their respective valves (AORTIC VALVE; PULMONARY VALVE).Extracellular Fluid: The fluid of the body that is outside of CELLS. It is the external environment for the cells.Hydrocephalus: Excessive accumulation of cerebrospinal fluid within the cranium which may be associated with dilation of cerebral ventricles, INTRACRANIAL HYPERTENSION; HEADACHE; lethargy; URINARY INCONTINENCE; and ATAXIA.