The short version of neurotrophic factor fits in a sentence. The long version — which is the one that helps — is below.
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Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
| Property | Value | Notes |
|---|---|---|
| Molecular weight | ~813.9 Da (free heptapeptide) | N-acetylated form is about 42 Da heavier |
| Residue count | 7 (heptapeptide) | Four residues from ACTH(4-10), three added |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility class | Freely soluble in water | Also dissolves in DMSO and polar organic solvents |
| Related parent fragment | ACTH(4-10) | Parent motif is Met-Glu-His-Phe |
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
At clinically studied doses in humans (up to 600 mg/day), which are much lower on a mg/kg basis than those used in the preceding animal studies, bicalutamide has only shown increases in testosterone levels and no testosterone suppression. There is some indication that the related NSAA nilutamide may also have SARM-like properties in certain tissues, as suggested by stimulation of erythropoiesis in men with prostate cancer. Additionally, hydroxyflutamide, the active metabolite of the related NSAA flutamide, has shown SARM-like activity in an androgen-responsive osteoblast cell line. Similarly, along with CPA, flutamide and hydroxyflutamide, though not bicalutamide, have been reported to act as SARMs or AR partial agonists in prostate cancer cells. Novel SARMs like enobosarm, with antiandrogenic effects in the prostate gland like bicalutamide but potent anabolic effects in muscle and bone, have also been developed. Bicalutamide has also been described as a functional "SARM" due to peripheral selectivity and inability to cross into the central nervous system and block ARs in this part of the body, resulting in antiandrogenic action in the periphery and lack of effects in the brain. However, while peripheral selectivity was initially observed in animal studies, bicalutamide did not end up showing peripheral selectivity in humans.
Foreign versions of Lipitor and Celebrex were smuggled into the U.S. from South America and resold after being repackaged to conceal the true origin of the drugs. Counterfeit Lipitor was manufactured in South America and smuggled into the US, where it sold after commingling with the genuine foreign Lipitor. Participants conspired to buy, sell and traffic almost eight million dollars' worth of stolen Glaxo Smith Kline and Roche drugs, using fake pedigrees to launder the drugs and thereby concealing that they were stolen. There also were charges related to the sale of counterfeit Procrit, as well as counterfeit and misbranded Serostim and Neupogen. Procrit is an injectable drug used in the treatment of anemia, Serostim is Serono's brand name form of synthetic somatropin (i.e. human growth hormone formed using laboratory methods of genetic recombination) marketed for HIV-associated wasting, and Neupogen is an injectable drug used by cancer patients to stimulate the production of white blood cells in order to decrease the incidence of infections. In 2005, the FDA held a Congressional hearing to review the situation. The U.S. is an especially attractive market for counterfeiters, because 40% of worldwide annual prescription drug sales were made in the United States in 2007. In 2011, a "PROTECT IP Act" was proposed to deter advertising. Between 2002 and 2010, drug imports to the U.S. more than doubled, with 80% of drugs' active ingredients imported, now accounting for 40% of finished medicines. In 2015, the U.S.
Examples: [Co(EDTA)]−, [Co(NH3)6]3+, TiCl4(THF)2. Coordination compounds show a rich diversity of structures, varying from tetrahedral for titanium (e.g., TiCl4) to square planar for some nickel complexes to octahedral for coordination complexes of cobalt. A range of transition metals can be found in biologically important compounds, such as iron in hemoglobin.
=== Spread of Enlightenment ideals === Other factors may include Enlightenment thinking and the examples of the Atlantic Revolutions. The Enlightenment spurred the desire for social and economic reform to spread throughout Spanish America and the Iberian Peninsula. Ideas about free trade and physiocratic economics were raised by the Enlightenment in Spain and spread to the overseas empire and a homegrown Spanish American Enlightenment. The political reforms implemented and the many constitutions written both in Spain and throughout the Spanish world during the wars of independence were influenced by these factors.
The most commonly reported adverse effects for I.V. formulations of acetylcysteine are rash, urticaria, and itchiness. Adverse effects for inhalational formulations of acetylcysteine include nausea, vomiting, stomatitis, fever, rhinorrhea, drowsiness, clamminess, chest tightness, and bronchoconstriction. Although infrequent, bronchospasm has been reported to occur unpredictably in some patients. Adverse effects for oral formulations of acetylcysteine have been reported to include nausea, vomiting, rash, and fever. Large doses in a mouse model showed that acetylcysteine could potentially cause damage to the heart and lungs. They found that acetylcysteine was metabolized to S-nitroso-N-acetylcysteine (SNOAC), which increased blood pressure in the lungs and right ventricle of the heart (pulmonary artery hypertension) in mice treated with acetylcysteine. The effect was similar to that observed following a 3-week exposure to an oxygen-deprived environment (chronic hypoxia). The authors also found that SNOAC induced a hypoxia-like response in the expression of several important genes both in vitro and in vivo. The implications of these findings for long-term treatment with acetylcysteine have not yet been investigated. The dose used by Palmer and colleagues was dramatically higher than that used in humans, the equivalent of about 20 grams per day. In humans, much lower dosages (600 mg per day) have been observed to counteract some age-related decline in the hypoxic ventilatory response as tested by inducing prolonged hypoxia.
Sources: en.wikipedia.org
==== MeSH E05.601.495 – immunoassay ==== MeSH E05.601.495.320 – immunoblotting MeSH E05.601.495.320.200 – blotting, western MeSH E05.601.495.350 – immunoenzyme techniques MeSH E05.601.495.350.170 – enzyme-linked immunosorbent assay MeSH E05.601.495.350.180 – enzyme multiplied immunoassay technique MeSH E05.601.495.380 – immunosorbent techniques MeSH E05.601.495.380.360 – enzyme-linked immunosorbent assay MeSH E05.601.495.380.810 – radioallergosorbent test MeSH E05.601.495.380.825 – radioimmunoprecipitation assay MeSH E05.601.495.380.830 – radioimmunosorbent test MeSH E05.601.495.639 – radioimmunoassay MeSH E05.601.495.639.405 – immunoradiometric assay MeSH E05.601.495.639.810 – radioallergosorbent test MeSH E05.601.495.639.825 – radioimmunoprecipitation assay MeSH E05.601.495.639.830 – radioimmunosorbent test
Clinical pharmacokinetics (arising from the clinical use of population pharmacokinetics) is the direct application to a therapeutic situation of knowledge regarding a drug's pharmacokinetics and the characteristics of a population that a patient belongs to (or can be ascribed to). An example is the relaunch of the use of ciclosporin as an immunosuppressor to facilitate organ transplant. The drug's therapeutic properties were initially demonstrated, but it was almost never used after it was found to cause nephrotoxicity in a number of patients. However, it was then realized that it was possible to individualize a patient's dose of ciclosporin by analyzing the patients plasmatic concentrations (pharmacokinetic monitoring). This practice has allowed this drug to be used again and has facilitated a great number of organ transplants. Clinical monitoring is usually carried out by determination of plasma concentrations as this data is usually the easiest to obtain and the most reliable. The main reasons for determining a drug's plasma concentration include:
=== Plastic packaging violation case === In 2011, the Supreme Court of India issued a contempt notice to Dharampal Satyapal Limited for allegedly violating a ban on the use of plastic sachets for selling products. A representative from the Centre for Public Interest Litigation, the non-governmental organisation that originally filed the petition, claimed that the company attempted to circumvent the ban by labeling plastic-packaged products as "for export only," while they were instead sold domestically.
After these winds slow down, sub-tropical westerlies guide extratropical Western disturbances from the Mediterranean Region and the Middle East across northwestern India, bringing rain for winter crops and replenishing the glaciers in the Karakorams. By May, the sun bakes the Tibetan Plateau. Rising warm air generates a high-altitude anticyclone. This creates the Tropical Easterly Jet Stream over southern India, which draws moisture-laden southwesterly surface winds off the Indian Ocean. The Western Ghats intercept these winds, which release their moisture as orographic rain, leaving a large swath of peninsular India in the mountains' rain shadow. India’s interior plains rely on monsoon depressions for their rain. These low-pressure storm systems form over the Bay of Bengal and are steered clockwise and inland by the anticyclonic jet stream. They cause summer rainfall across India from June to September. However, rainfall fluctuates in cycles, alternating between active phases characterised by heavy rain and dry breaks.
Sources: en.wikipedia.org
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.
Semax is a synthetic analog of the ACTH(4-10) fragment rather than a copy of the full hormone. Truncation plus the added tail removes the steroidogenic portion of ACTH. That distinction explains why it is studied for nervous-system effects instead of adrenal stimulation.
It is registered as a prescription product in Russia and has been used there clinically, chiefly by the intranasal route. No approval exists in the United States or the European Union. Availability elsewhere typically falls under research-chemical distribution, with varying purity documentation.
不存在。它是依据 ACTH 的一段序列人工设计的分子，天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号，而非天然物质名。