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Ornitrol
Azacosterol (), or azacosterol hydrochloride () (brand name Ornitrol), also known as 20,25-diazacholesterol, is a cholesterol-lowering drug (hypocholesteremic), which was marketed previously, but has since been discontinued. It is also an avian chemosterilant used to control pest pigeon populations via inducing sterility. The drug is a sterol and derivative of cholesterol in which two carbon atoms have been replaced with nitrogen atoms. Azacosterol acts as an inhibitor of 24-dehydrocholesterol reductase (24-DHCR), preventing the formation of cholesterol from desmosterol. Although it primarily acts to inhibit 24-DHCR, the drug also inhibits other steps in cholesterol biosynthesis. The antifertility effects of the drug in birds are mediated by inhibition of steroid hormone production, steroid hormones being synthesized from cholesterol. Due to prevention of the metabolism of desmosterol, the drug causes it to accumulate, in turn producing side effects such as hyperkeratosis, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemosterilant
A chemosterilant is a chemical compound that causes reproductive sterility in an organism. Chemosterilants are particularly useful in controlling the population of species that are known to cause disease, such as insects, or species that are, in general, economically damaging. The sterility induced by chemosterilants can have temporary or permanent effects. Chemosterilants can be used to target one or both sexes, and it prevents the organism from advancing to be sexually functional. They may be used to control pest populations by sterilizing males. The need for chemosterilants is a direct consequence of the limitations of insecticides. Insecticides are most effective in regions in which there is high vector density in conjunction with endemic transmission, and this may not always be the case. Additionally, the insects themselves will develop a resistance to the insecticide either on the target protein level or through avoidance of the insecticide in what is called a behavioral res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oral Administration
Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are intended to have a systemic effect, reaching different parts of the body via the bloodstream, for example. Oral administration can be easier and less painful than other routes, such as injection. However, the onset of action is relatively low, and the effectiveness is reduced if it is not absorbed properly in the digestive system, or if it is broken down by digestive enzymes before it can reach the bloodstream. Some medications may cause gastrointestinal side effects, such as nausea or vomiting, when taken orally. Oral administration can also only be applied to conscious patients, and patients willing and able to swallow. Terminology ''Per os'' (; ''P.O.'') is an adverbial phrase meaning literally from Latin "through the mouth" or "by mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmosterol
Desmosterol is a molecule similar to cholesterol. Desmosterol is the immediate precursor of cholesterol in the Bloch pathway of cholesterol biosynthesis. 24-dehydrocholesterol reductase catalyses the reduction of desmosterol to cholesterol. It is accumulated in desmosterolosis. In 2014, it was named the Molecule of the Year The Breakthrough of the Year is an annual award for the most significant development in scientific research made by the AAAS journal '' Science,'' an academic journal covering all branches of science. Originating in 1989 as the ''Molecule of the Y ... 2012 by the International Society for Molecular and Cell Biology and Biotechnology Protocols and Researches ( ISMCBBPR). See also * Triparanol References Cholestanes {{steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypolipidemic Agents
Lipid-lowering agents, also sometimes referred to as hypolipidemic agents, cholesterol-lowering drugs, or antihyperlipidemic agents are a diverse group of pharmaceuticals that are used to lower the level of lipids and lipoproteins such as cholesterol, in the blood (hyperlipidemia). The American Heart Association recommends the descriptor 'lipid lowering agent' be used for this class of drugs rather than the term 'hypolipidemic'. Classes The several classes of lipid lowering drugs may differ in both their impact on the cholesterol profile and adverse effects. For example, some may lower low density lipoprotein (LDL) levels more so than others, while others may preferentially increase high density lipoprotein (HDL). Clinically, the choice of an agent depends on the patient's cholesterol profilecardiovascular risk and the liver and kidney functions of the patient, evaluated against the balancing of risks and benefits of the medications. In the United States, this is guided by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-linked Ichthyosis
X-linked ichthyosis (abbreviated ''XLI'') is a skin condition caused by the hereditary deficiency of the steroid sulfatase (STS) enzyme that affects 1 in 2000 to 1 in 6000 males. XLI manifests with dry, scaly skin and is due to deletions or mutations in the ''STS'' gene. XLI can also occur in the context of larger deletions causing contiguous gene syndromes. Treatment is largely aimed at alleviating the skin symptoms.: Treatment Section The term is from the Ancient Greek 'ichthys' meaning 'fish'. Signs and symptoms The major symptoms of XLI include scaling of the skin, particularly on the neck, trunk, and lower extremities. The extensor surfaces are typically the most severely affected areas. The >4 mm diameter scales adhere to the underlying skin and can be dark brown or gray in color. Symptoms may subside during the summer. Associated medical conditions Aside from the skin scaling, XLI is not typically associated with other major medical problems. Atrial fibri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triparanol
Triparanol (, ; brand name and development code MER/29, as well as many other brand names) was the first synthetic cholesterol-lowering drug. It was patented in 1959 and introduced in the United States in 1960. The developmental code name of triparanol, MER/29, became so well known that it became the registered trade name of the drug. It was withdrawn in 1962 due to severe adverse effects such as nausea and vomiting, vision loss due to irreversible cataracts, alopecia, skin disorders (e.g., dryness, itching, peeling, and "fish-scale" texture), and accelerated atherosclerosis. It is now considered to be obsolete. The drug acts by inhibiting 24-dehydrocholesterol reductase, which catalyzes the final step of cholesterol biosynthesis, the conversion of desmosterol into cholesterol. Although effective in reducing cholesterol levels, this results in tissue accumulation of desmosterol, which in turn is responsible for the side effects of triparanol. Unlike statins, triparanol does no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmosterolosis
Desmosterolosis in medicine and biology is a defect in cholesterol biosynthesis. It results in an accumulation of desmosterol and a variety of associated symptoms. Only two cases have been reported as of 2007. The condition is due to inactivating mutations in 24-dehydrocholesterol reductase. Certain anticholesterolemic and antiestrogenic drugs such as triparanol, ethamoxytriphetol, and clomifene have been found to inhibit conversion of desmosterol into cholesterol and to induce desmosterolosis, for instance cataract A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colors, blurry or double vision, halos around light, trouble ...s. References External links Cholesterol and steroid metabolism disorders {{Endocrine-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sole (foot)
The sole is the bottom of the foot. In humans the sole of the foot is anatomically referred to as the plantar aspect. Structure The glabrous skin on the sole of the foot lacks the hair and pigmentation found elsewhere on the body, and it has a high concentration of sweat pores. The sole contains the thickest layers of skin on the body due to the weight that is continually placed on it. It is crossed by a set of creases that form during the early stages of embryonic development. Like those of the palm, the sweat pores of the sole lack sebaceous glands. The sole is a sensory organ by which we can perceive the ground while standing and walking. The subcutaneous tissue in the sole has adapted to deal with the high local compressive forces on the heel and the ball (between the toes and the arch) by developing a system of "pressure chambers." Each chamber is composed of internal fibrofatty tissue covered by external collagen connective tissue. The septa (internal walls) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hand
A hand is a prehensile, multi-fingered appendage located at the end of the forearm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. A few other vertebrates such as the koala (which has two opposable thumbs on each "hand" and fingerprints extremely similar to human fingerprints) are often described as having "hands" instead of paws on their front limbs. The raccoon is usually described as having "hands" though opposable thumbs are lacking. Some evolutionary anatomists use the term ''hand'' to refer to the appendage of digits on the forelimb more generally—for example, in the context of whether the three digits of the bird hand involved the same homologous loss of two digits as in the dinosaur hand. The human hand usually has five digits: four fingers plus one thumb; these are often referred to collectively as five fingers, however, whereby the thumb is included as one of the fingers. It has 27 bones, not including the sesamoid bone, the numbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperkeratosis
Hyperkeratosis is thickening of the stratum corneum (the outermost layer of the epidermis, or skin), often associated with the presence of an abnormal quantity of keratin,Kumar, Vinay; Fausto, Nelso; Abbas, Abul (2004) ''Robbins & Cotran Pathologic Basis of Disease'' (7th ed.). Saunders. Page 1230. . and also usually accompanied by an increase in the granular layer. As the corneum layer normally varies greatly in thickness in different sites, some experience is needed to assess minor degrees of hyperkeratosis. It can be caused by vitamin A deficiency or chronic exposure to arsenic. Hyperkeratosis can also be caused by B-Raf inhibitor drugs such as Vemurafenib and Dabrafenib.Niezgoda, Anna; Niezgoda, Piotr; Czajkowski, Rafal (2015) ''Novel Approaches to Treatment of Advanced Melanoma: A Review of Targeted Therapy and Immunotherapy'' BioMed Research International It can be treated with urea-containing creams, which dissolve the intercellular matrix of the cells of the stratum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Side Effect
In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequences of the use of a drug. Developing drugs is a complicated process, because no two people are exactly the same, so even drugs that have virtually no side effects, might be difficult for some people. Also, it is difficult to make a drug that targets one part of the body but that does not affect other parts, the fact that increases the risk of side effects in the untargeted parts. Occasionally, drugs are prescribed or procedures performed specifically for their side effects; in that case, said side effect ceases to be a side effect and is now an intended effect. For instance, X-rays were historically (and are currently) used as an imaging technique; the discovery of their oncolytic capability led to their employ in radiotherapy (ablation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
