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The vast majority of glucocorticoid activity in most mammals is from cortisol, also known as hydrocortisone. Corticosterone, the major glucocorticoid in rodents, is another glucocorticoid. Cortisol binds to the glucocorticoid receptor in the cytoplasm and the hormone-receptor complex is then translocated into the nucleus, where it binds to its DNA response element and modulates transcription from a battery of genes, leading to changes in the cell's phenotype. Only about 10% of circulating cortisol is free. The remaining majority circulates bound to plasma proteins, particularly corticosteroid-binding globulin (transcortin). This protein binding likely decreases the metabolic clearance rate of glucocorticoids and, because the bound steroid is not biologically active, tends to act as a buffer and blunt wild fluctuations in cortisol concentration.
Two types of clinically distinct necrotizing fasciitis have been described. The most common form (type II) usually occurs in individuals with no concurrent medical illness. Many patients report a history of laceration, blunt trauma, or a surgical procedure as a predisposing factor. It is typically caused by group A Streptococcus (Streptococcus pyogenes). In contrast, type I is usually seen in patients with underlying diabetes and peripheral vascular disease. It is generally a polymicrobial infection; some commonly isolated organisms include Staphylococcus aureus, Bacteroides tragi/is, Escherichia coli, group A Streptococcus, and Pre vote/fa species. Crepitus is more common if anaerobic organisms, such as Clostridium perfringens or 8 tragi/is, are involved.
Progressive multifocalleukoencephalopathy is a demyelinating illness of the central nervous system that typically occurs in immunosuppressed patients, especially those with AIDS. It is caused by reactivation of the polyomavirus JC (JC virus) and presents with neurologic deficits including hemiparesis, gait ataxia, visual symptoms, and altered mental status. It is not seen in non-immunosuppressed patients, and fever is not typical
The cause of HELLP syndrome is unknown, but there are certain factors that may increase your risk of developing it. Preeclampsia is the greatest risk factor. This condition is marked by high blood pressure and swelling, and it typically occurs during the last trimester of pregnancy.
The core features of migraine are headache, which is usually throbbing and often unilateral, and associated features of nausea, sensitivity to light, sound, and exacerbation with head movement. Migraine has long been regarded as a vascular disorder because of the throbbing nature of the pain.
A deep cut on the palm side of your fingers, hand, wrist, or forearm can damage your flexor tendons, which are the tissues that help control movement in your hand. A flexor tendon injury can make it impossible to bend your fingers or thumb.
giant systolic pulsations, known as C-V waves, were noticeable during jugular venous examination of a 33-year-old woman who had tricuspid-valve endocarditis. In video 2, transthoracic echocardiography revealed severe tricuspid regurgitation.
An antisperm antibody test looks for special proteins (antibodies) that fight against a man's sperm in blood, vaginal fluids, or semen. The test uses a sample of sperm and adds a substance that binds only to affected sperm. Semen can cause an immune system response in either the man's or woman's body. The antibodies can damage or kill sperm. If a high number of sperm antibodies come into contact with a man's sperm, it may be hard for the sperm to fertilize an egg. The couple has a hard time becoming pregnant. This is called immunologic infertility.
Frostbite is an injury caused by freezing of the skin and underlying tissues. First your skin becomes very cold and red, then numb, hard and pale. Frostbite is most common on the fingers, toes, nose, ears, cheeks and chin. Exposed skin in cold, windy weather is most vulnerable to frostbite. But frostbite can occur on skin covered by gloves or other clothing.