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Sirolimus
Sirolimus, also known as rapamycin and sold under the brand name Rapamune among others, is a macrolide compound that is used to coat coronary stents, prevent organ transplant rejection, treat a rare lung disease called lymphangioleiomyomatosis, and treat perivascular epithelioid cell tumor (PEComa). It has immunosuppressant functions in humans and is especially useful in preventing the rejection of kidney transplants. It is a mechanistic target of rapamycin kinase (mTOR) inhibitor that inhibits activation of T cells and B cells by reducing their sensitivity to interleukin-2 (IL-2). It is produced by the bacterium '' Streptomyces hygroscopicus'' and was isolated for the first time in 1972, from samples of ''Streptomyces hygroscopicus'' found on Easter Island. The compound was originally named rapamycin after the native name of the island, Rapa Nui. Sirolimus was initially developed as an antifungal agent. However, this use was abandoned when it was discovered to have potent immun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphangioleiomyomatosis
Lymphangioleiomyomatosis (LAM) is a rare, progressive and systemic disease that typically results in cystic lung destruction. It predominantly affects women, especially during childbearing years. The term sporadic LAM is used for patients with LAM not associated with tuberous sclerosis complex (TSC), while TSC-LAM refers to LAM that is associated with TSC. Signs and symptoms The average age of onset is the early to mid 30s. Exertional dyspnea (shortness of breath) and spontaneous pneumothorax (lung collapse) have been reported as the initial presentation of the disease in 49% and 46% of patients, respectively. Diagnosis is typically delayed 5 to 6 years. The condition is often misdiagnosed as asthma or chronic obstructive pulmonary disease. The first pneumothorax, or lung collapse, precedes the diagnosis of LAM in 82% of patients. The consensus clinical definition of LAM includes multiple symptoms: * Fatigue * Cough * Hemoptysis, Coughing up blood (rarely massive) * Chest pain * C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MTOR Inhibitors
mTOR inhibitors are a drug class, class of drugs that inhibit the mechanistic target of rapamycin (mTOR), which is a serine/threonine-specific protein kinase that belongs to the family of Phosphoinositide 3-kinase, phosphatidylinositol-3 kinase (PI3K) related kinases (PIKKs). mTOR regulates cellular metabolism, growth, and proliferation by forming and signaling through two protein complexes, mTORC1 and mTORC2. The most established mTOR inhibitors are so-called rapalogs (rapamycin and its analogs), which have shown tumor responses in clinical trials against various tumor types. History The discovery of mTOR was made a few decades ago while investigating the mechanism of action of its enzyme inhibitor, inhibitor, rapamycin. Rapamycin was first discovered in 1975 in a soil sample from Easter Island of Oceania, South Pacific, also known as Rapa Nui, from where its name is derived. Rapamycin is a macrolide, produced by the microorganism ''Streptomyces hygroscopicus'' and showed antifun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcineurin Inhibitor
Immunosuppressive drugs, also known as immunosuppressive agents, immunosuppressants and antirejection medications, are drugs that inhibit or prevent activity of the immune system. Classification Immunosuppressive drugs can be classified into five groups: * glucocorticoids * cytostatics * antibodies * drugs acting on immunophilins * other drugs Glucocorticoids In pharmacologic (supraphysiologic) doses, glucocorticoids, such as prednisone, dexamethasone, and hydrocortisone are used to suppress various allergic, inflammatory, and autoimmune disorders. They are also administered as posttransplantory immunosuppressants to prevent the acute transplant rejection and graft-versus-host disease. Nevertheless, they do not prevent an infection and also inhibit later reparative processes. Immunosuppressive mechanism Glucocorticoids suppress cell-mediated immunity. They act by inhibiting genes that code for the cytokines Interleukin 1 (IL-1), IL-2, IL-3, IL-4, IL-5, IL-6, IL ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunosuppressant
Immunosuppressive drugs, also known as immunosuppressive agents, immunosuppressants and antirejection medications, are drugs that inhibit or prevent activity of the immune system. Classification Immunosuppressive drugs can be classified into five groups: * glucocorticoids * cytostatics * antibodies * drugs acting on immunophilins * other drugs Glucocorticoids In pharmacologic (supraphysiologic) doses, glucocorticoids, such as prednisone, dexamethasone, and hydrocortisone are used to suppress various allergic, inflammatory, and autoimmune disorders. They are also administered as posttransplantory immunosuppressants to prevent the acute transplant rejection and graft-versus-host disease. Nevertheless, they do not prevent an infection and also inhibit later reparative processes. Immunosuppressive mechanism Glucocorticoids suppress cell-mediated immunity. They act by inhibiting genes that code for the cytokines Interleukin 1 (IL-1), IL-2, IL-3, IL-4, IL-5, IL- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organ Rejection
Transplant rejection occurs when transplanted tissue is rejected by the recipient's immune system, which destroys the transplanted tissue. Transplant rejection can be lessened by determining the molecular similitude between donor and recipient and by use of immunosuppressant drugs after transplant. Types of transplant rejection Transplant rejection can be classified into three types: hyperacute, acute, and chronic. These types are differentiated by how quickly the recipient's immune system is activated and the specific aspect or aspects of immunity involved. Hyperacute rejection Hyperacute rejection is a form of rejection that manifests itself in the minutes to hours following transplantation. It is caused by the presence of pre-existing antibodies in the recipient that recognize antigens in the donor organ. These antigens are located on the endothelial lining of blood vessels within the transplanted organ and, once antibodies bind, will lead to the rapid activation of the comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomyces Hygroscopicus
''Streptomyces hygroscopicus'' is a bacterial species in the genus '' Streptomyces''. It was first described by Hans Laurits Jensen in 1931. Biochemistry Cultures of different strains of ''S. hygroscopicus'' can be used to produce a number of chemical compounds or enzymes. Small molecules Immunosuppressants Sirolimus (also known as rapamycin) is an immunosuppressant that has been isolated from ''S. hygroscopicus'' from soil samples from Easter Island. Ascomycin can be used to treat autoimmune diseases and skin diseases, and can help prevent rejection after an organ transplant. Antibiotics The antibiotics geldanamycin, hygromycin B, nigericin, validamycin, and cyclothiazomycin are found in ''S. hygroscopicus''. Experimental cancer drugs Indolocarbazoles can be found in ''S. hygroscopicus'' . Anthelmintics and insecticides Milbemycin and milbemycin oxime can be found in ''S. hygroscopicus'' cultures. Herbicide ''S. hygroscopicus'' also produces the natural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycophenolate Mofetil
Mycophenolic acid (MPA) is an immunosuppressant medication used to prevent rejection following organ transplantation and to treat autoimmune conditions such as Crohn's disease and lupus. Specifically it is used following kidney, heart, and liver transplantation. It can be given by mouth or by injection into a vein. It comes as mycophenolate sodium and mycophenolate mofetil. Common side effects include nausea, infections, and diarrhea. Other serious side effects include an increased risk of cancer, progressive multifocal leukoencephalopathy, anemia, and gastrointestinal bleeding. Use during pregnancy may harm the baby. It works by blocking inosine monophosphate dehydrogenase (IMPDH), which is needed by lymphocytes to make guanosine. Mycophenolic acid was initially discovered by Italian Bartolomeo Gosio in 1893. It was rediscovered in 1945 and 1968. It was approved for medical use in the United States in 1995 following the discovery of its immunosuppressive properties in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombocytopenia
Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients and a third of surgical patients. A normal human platelet count ranges from 150,000 to 450,000 platelets/microliter (μl) of blood. Values outside this range do not necessarily indicate disease. One common definition of thrombocytopenia requiring emergency treatment is a platelet count below 50,000/μl. Thrombocytopenia can be contrasted with the conditions associated with an abnormally ''high'' level of platelets in the blood - thrombocythemia (when the cause is unknown), and thrombocytosis (when the cause is known). Signs and symptoms Thrombocytopenia usually has no symptoms and is picked up on a routine complete blood count. Some individuals with thrombocytopenia may experience external bleeding, such as nosebleeds or bleeding gums. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antifungal Medication
An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as cryptococcal meningitis, and others. Such drugs are usually yes obtained by a doctor's prescription, but a few are available over the counter (OTC). Types of antifungal There are two types of antifungals: local and systemic. Local antifungals are usually administered topically or vaginally, depending on the condition being treated. Systemic antifungals are administered orally or intravenously. Of the clinically employed azole antifungals, only a handful are used systemically. These include ketoconazole, itraconazole, fluconazole, fosfluconazole, voriconazole, posaconazole, and isavuconazole. Examples of non-azole systemic antifungals include griseofulvin and terbinafine. Classes Polyenes A polyene is a molecule with multiple conjugated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smooth Muscle Tissue
Smooth muscle is an involuntary non-striated muscle, so-called because it has no sarcomeres and therefore no striations (''bands'' or ''stripes''). It is divided into two subgroups, single-unit and multiunit smooth muscle. Within single-unit muscle, the whole bundle or sheet of smooth muscle cells contracts as a syncytium. Smooth muscle is found in the walls of hollow organs, including the stomach, intestines, bladder and uterus; in the walls of passageways, such as blood, and lymph vessels, and in the tracts of the respiratory, urinary, and reproductive systems. In the eyes, the ciliary muscles, a type of smooth muscle, dilate and contract the iris and alter the shape of the lens. In the skin, smooth muscle cells such as those of the arrector pili cause hair to stand erect in response to cold temperature or fear. Structure Gross anatomy Smooth muscle is grouped into two types: single-unit smooth muscle, also known as visceral smooth muscle, and multiunit smooth muscle. M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kidney Failure
Kidney failure, also known as end-stage kidney disease, is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as either acute kidney failure, which develops rapidly and may resolve; and chronic kidney failure, which develops slowly and can often be irreversible. Symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications of acute and chronic failure include uremia, high blood potassium, and volume overload. Complications of chronic failure also include heart disease, high blood pressure, and anemia. Causes of acute kidney failure include low blood pressure, blockage of the urinary tract, certain medications, muscle breakdown, and hemolytic uremic syndrome. Causes of chronic kidney failure include diabetes, high blood pressure, nephrotic syndrome, and polycystic kidney disease. Diagnosis of acute failure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
