Stem cellIn multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can differentiate into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of cell in a cell lineage. They are found in both embryonic and adult organisms, but they have slightly different properties in each. They are usually distinguished from progenitor cells, which cannot divide indefinitely, and precursor or blast cells, which are usually committed to differentiating into one cell type.
Embryonic stem cellEmbryonic stem cells (ESCs) are pluripotent stem cells derived from the inner cell mass of a blastocyst, an early-stage pre-implantation embryo. Human embryos reach the blastocyst stage 4–5 days post fertilization, at which time they consist of 50–150 cells. Isolating the inner cell mass (embryoblast) using immunosurgery results in destruction of the blastocyst, a process which raises ethical issues, including whether or not embryos at the pre-implantation stage have the same moral considerations as embryos in the post-implantation stage of development.
Immortalised cell lineAn immortalised cell line is a population of cells from a multicellular organism which would normally not proliferate indefinitely but, due to mutation, have evaded normal cellular senescence and instead can keep undergoing division. The cells can therefore be grown for prolonged periods in vitro. The mutations required for immortality can occur naturally or be intentionally induced for experimental purposes. Immortal cell lines are a very important tool for research into the biochemistry and cell biology of multicellular organisms.
EpidemiologyEpidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population. It is a cornerstone of public health, and shapes policy decisions and evidence-based practice by identifying risk factors for disease and targets for preventive healthcare. Epidemiologists help with study design, collection, and statistical analysis of data, amend interpretation and dissemination of results (including peer review and occasional systematic review).
Reporter geneIn molecular biology, a reporter gene (often simply reporter) is a gene that researchers attach to a regulatory sequence of another gene of interest in bacteria, cell culture, animals or plants. Such genes are called reporters because the characteristics they confer on organisms expressing them are easily identified and measured, or because they are selectable markers. Reporter genes are often used as an indication of whether a certain gene has been taken up by or expressed in the cell or organism population.
Prostate cancerProstate cancer is the uncontrolled growth of cells in the prostate, a gland in the male reproductive system just below the bladder. Early prostate cancer usually causes no symptoms. As the tumor grows, it can damage nearby organs causing erectile dysfunction, blood in the urine or semen, and trouble urinating. Some tumors eventually spread to other areas of the body, particularly the bones and lymph nodes. There, tumors cause severe bone pain, leg weakness or paralysis, and eventually death.
Combined injectable birth controlCombined injectable contraceptives (CICs) are a form of hormonal birth control for women. They consist of monthly injections of combined formulations containing an estrogen and a progestin to prevent pregnancy. CICs are different from progestogen-only injectable contraceptives (POICs), such as depot medroxyprogesterone acetate (DMPA; brand names Depo-Provera, Depo-SubQ Provera 104) and norethisterone enantate (NETE; brand name Noristerat), which are not combined with an estrogen and are given once every two to three months instead of once a month.
Bis(2-ethylhexyl) phthalateBis(2-ethylhexyl) phthalate (di-2-ethylhexyl phthalate, diethylhexyl phthalate, diisooctyl phthalate, DEHP; incorrectly — dioctyl phthalate, DIOP) is an organic compound with the formula C6H4(CO2C8H17)2. DEHP is the most common member of the class of phthalates, which are used as plasticizers. It is the diester of phthalic acid and the branched-chain 2-ethylhexanol. This colorless viscous liquid is soluble in oil, but not in water.
Combined oral contraceptive pillThe combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. The pill contains two important hormones: a progestin (a synthetic form of the hormone progestogen/progesterone) and estrogen (usually ethinylestradiol or 17β estradiol). When taken correctly, it alters the menstrual cycle to eliminate ovulation and prevent pregnancy.
Brain tumorA brain tumor occurs when abnormal cells form within the brain. There are two main types of tumors: malignant tumors and benign (non-cancerous) tumors. These can be further classified as primary tumors, which start within the brain, and secondary tumors, which most commonly have spread from tumors located outside the brain, known as brain metastasis tumors. All types of brain tumors may produce symptoms that vary depending on the size of the tumor and the part of the brain that is involved.
