Clostridioides difficileClostridioides difficile (syn. Clostridium difficile) is a bacterium that is well known for causing serious diarrheal infections, and may also cause colon cancer. It is known also as C. difficile, or C. diff (siː_dɪf), and is a Gram-positive species of spore-forming bacteria. Clostridioides spp. are anaerobic, motile bacteria, ubiquitous in nature and especially prevalent in soil. Its vegetative cells are rod-shaped, pleomorphic, and occur in pairs or short chains.
CholesterolCholesterol is the principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell membranes. In vertebrates, hepatic cells typically produce the greatest amounts. It is absent among prokaryotes (bacteria and archaea), although there are some exceptions, such as Mycoplasma, which require cholesterol for growth.
Inverse agonistIn pharmacology, an inverse agonist is a drug that binds to the same receptor as an agonist but induces a pharmacological response opposite to that of the agonist. A neutral antagonist has no activity in the absence of an agonist or inverse agonist but can block the activity of either; they are in fact sometimes called blockers (examples include alpha blockers, beta blockers, and calcium channel blockers). Inverse agonists have opposite actions to those of agonists but the effects of both of these can be blocked by antagonists.
Microscopic colitisMicroscopic colitis refers to two related medical conditions which cause diarrhea: collagenous colitis and lymphocytic colitis. Both conditions are characterized by the presence of chronic non-bloody watery diarrhea, normal appearances on colonoscopy and characteristic histopathology findings of inflammatory cells. The main symptom is persistent non-bloody watery diarrhea, which may be profuse. People may also experience abdominal pain, fecal incontinence, and unintentional weight loss.
AmoebiasisAmoebiasis, or amoebic dysentery, is an infection of the intestines caused by a parasitic amoeba Entamoeba histolytica. Amoebiasis can be present with no, mild, or severe symptoms. Symptoms may include lethargy, loss of weight, colonic ulcerations, abdominal pain, diarrhea, or bloody diarrhea. Complications can include inflammation and ulceration of the colon with tissue death or perforation, which may result in peritonitis. Anemia may develop due to prolonged gastric bleeding.
Granulocyte-macrophage colony-stimulating factorGranulocyte-macrophage colony-stimulating factor (GM-CSF), also known as colony-stimulating factor 2 (CSF2), is a monomeric glycoprotein secreted by macrophages, T cells, mast cells, natural killer cells, endothelial cells and fibroblasts that functions as a cytokine. The pharmaceutical analogs of naturally occurring GM-CSF are called sargramostim and molgramostim. Unlike granulocyte colony-stimulating factor, which specifically promotes neutrophil proliferation and maturation, GM-CSF affects more cell types, especially macrophages and eosinophils.
Malignant transformationMalignant transformation is the process by which cells acquire the properties of cancer. This may occur as a primary process in normal tissue, or secondarily as malignant degeneration of a previously existing benign tumor. There are many causes of primary malignant transformation, or tumorigenesis. Most human cancers in the United States are caused by external factors, and these factors are largely avoidable. These factors were summarized by Doll and Peto in 1981, and were still considered to be valid in 2015.
Beta particleA beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus during the process of beta decay. There are two forms of beta decay, β− decay and β+ decay, which produce electrons and positrons respectively. Beta particles with an energy of 0.5 MeV have a range of about one metre in the air; the distance is dependent on the particle energy.
Transforming growth factor betaTransforming growth factor beta (TGF-β) is a multifunctional cytokine belonging to the transforming growth factor superfamily that includes three different mammalian isoforms (TGF-β 1 to 3, HGNC symbols TGFB1, TGFB2, TGFB3) and many other signaling proteins. TGFB proteins are produced by all white blood cell lineages. Activated TGF-β complexes with other factors to form a serine/threonine kinase complex that binds to TGF-β receptors. TGF-β receptors are composed of both type 1 and type 2 receptor subunits.
Implantation (embryology)Implantation, also known as nidation is the stage in the embryonic development of mammals in which the blastocyst hatches, attaches, adheres, and invades into the wall of the female's uterus. Implantation is the first stage of gestation, and, when successful, the female is considered to be pregnant. An implanted embryo is detected by the presence of increased levels of human chorionic gonadotropin (hCG) in a pregnancy test. The implanted embryo will receive oxygen and nutrients in order to grow.
