Federation Project: Aging, Diabetes and Warburg Effect

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cancer

Any of a group of more than 100 distinct diseases that are characterized by the uncontrolled multiplication of abnormal cells. Cancerous cells and tissues have abnormal growth rates, shapes, sizes, and functioning. Cancer may progress in stages from a localized tumour (confined to the site of origin) to direct extension (spread into nearby tissue or lymph nodes) and metastasis (spread to more distant sites via the blood or lymphatic system). This malignant growth pattern distinguishes cancerous tumours from benign ones. Cancer is also classified by grade, the extent to which cell characteristics remain specific to their tissue of origin. Both stage and grade affect the chances of survival. Genetic factors and immune status affect susceptibility. Triggers include hormones, viruses, smoking, diet, and radiation. Cancer can begin in almost any tissue, as well as in the blood (see leukemia) and lymph (see lymphoma). When it metastasizes, it remains a cancer of its tissue of origin. Early diagnosis and treatment increase the chance of cure. Treatment may include chemotherapy, surgery, and radiation therapy. See also bladder cancer; breast cancer; carcinogen; colorectal cancer; Kaposi sarcoma; laryngeal cancer; lung cancer; ovarian cancer; pancreatic cancer; prostate cancer; skin cancer; stomach cancer; uterine cancer.

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diabetes mellitus

Disorder of insufficient production of or reduced sensitivity to insulin. Insulin, synthesized in the islets of Langerhans (see Langerhans, islets of), is necessary to metabolize glucose. In diabetes, blood sugar levels increase (hyperglycemia). Excess sugar is excreted in the urine (glycosuria). Symptoms include increased urine output, thirst, weight loss, and weakness. Type 1, or insulin-dependent diabetes mellitus (IDDM), an autoimmune disease in which no insulin is produced, must be treated by insulin injections. Type 2, or non-insulin-dependent diabetes mellitus (NIDDM), in which tissues do not respond to insulin, is linked to heredity and obesity and may be controlled by diet; it accounts for 90% of all cases, many of which go undiagnosed for years. Untreated diabetes leads to accumulation of ketones in the blood, followed by acidosis (high blood acid content) with nausea and vomiting and then coma. Careful attention to content and timing of meals, with periodic checking of blood sugar, may manage diabetes. If not, injected or oral insulin is necessary. Complications, including heart disease, diabetic retinopathy (a leading cause of blindness), kidney disease, and nerve disorders, especially in the legs and feet, account for most deaths. Degree of blood-sugar control does not always correlate with progression of complications. Gestational diabetes may occur as a complication of pregnancy.

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