This is a working overview of Semax, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-03-10. Anything still debated is marked as such rather than presented as settled.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Analog of an ACTH fragment |
| Amino acid length | Seven residues | Met-Glu-His-Phe-Pro-Gly-Pro |
| Origin | Moscow, 1980s | Institute of Molecular Genetics |
| Approved regions | Russia and some neighboring states | Not cleared in Western markets |
| Common trade names | Multiple national brands | Sold as a nasal formulation |
Secondary aromatic amines: These are less hindered than hindered phenols, which can make them more reactive. Hindered amine light stabilizers (HALS): Unlike other primary antioxidants, HALS scavenge free radicals generated during photo-oxidation, thus protecting the polymer material from UV radiation. Secondary antioxidants act to decompose peroxides (ROOH) into non-radical products, thus preventing further generation of free radicals, and contributing to the overall oxidative stability of the polymer. Often used in combination with phenolic antioxidants for synergistic effects. Phosphites: Example: tris(2,4-di-tert-butylphenyl)phosphite. Thiosynergists: Most of this class are "thio-ethers" (not to be confused with thioesters): an ester of 3,3-thiodipropionic acid. Other organic sulfide (R1-S-R2) compounds also have a similar effect. Radical scavengers: scavenge free radicals to halt the chain reaction. This can be any radical in the oxidation cycle (R•, ROO•, RO•, •OH), though in practice RO• and •OH are too reactive to "trap". Common types include lactones (esp. substituted benzofuranone) and acrylated bis-phenols.
=== Mechanism of action === Alitretinoin is believed to be the endogenous ligand (a substance that naturally occurs in the body that activates this receptor) for retinoid X receptor, but it also activates the retinoic acid receptor. More specifically, alitretinoin is believed to act on intracellular nuclear receptors of the RAR and RXR subtypes. The activated receptors function as transcription factors, which subsequently influence cell proliferation and cell differentiation. Alitretinoin acts on both keratinocytes and dendritic cells. In keratinocytes, it reduces cytokine expression, while in dendritic cells it inhibits the upregulation of the maturation marker CD83 and the co-stimulatory molecules CD80 and CD86. Consequently, these dendritic cells exhibit diminished T cell activation capacity.
The original transmitters were constantly upgraded, first from 100 kW of the Orfordness system to 350 kW for the deployed system, and then again to 750 kW during the war in order to offer greatly increased range. To aid in detection at long range, a slower 12.5 pulse per second rate was added. The four-tower transmitter was later reduced to three towers.
Sources: en.wikipedia.org
The vasopressins are peptides consisting of nine amino acids (nonapeptides). The amino acid sequence of arginine vasopressin (argipressin) is Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH2, with the cysteine residues forming a disulfide bond and the C-terminus of the sequence converted to a primary amide. Lysine vasopressin (lypressin) has a lysine in place of the arginine as the eighth amino acid, and is found in pigs and some related animals, whereas arginine vasopressin is found in humans. The structure of oxytocin is very similar to that of the vasopressins: It is also a nonapeptide with a disulfide bridge and its amino acid sequence differs at only two positions. The two genes are located on the same chromosome separated by a relatively small distance of less than 15,000 bases in most species. The magnocellular neurons that secrete vasopressin are adjacent to magnocellular neurons that secrete oxytocin, and are similar in many respects. The similarity of the two peptides can cause some cross-reactions: oxytocin has a slight antidiuretic function, and high levels of AVP can cause uterine contractions. Comparison of vasopressin and oxytocin neuropeptide families:
Repatriating the survivors of the 16 October strike on a semi-submersible to their home countries for prosecution avoids a civilian court challenge to continued detention without evidence, and a military court challenge to the legal justification for treating prisoners as unlawful combatants if they were not engaged in armed conflict.
CGRP mediates its effects through a heteromeric receptor composed of a G protein-coupled receptor called calcitonin receptor-like receptor (CALCRL) and RAMP1. CGRP receptors are found throughout all the body, suggesting that the protein may modulate a variety of physiological functions in all major systems (e.g., respiratory, endocrine, gastrointestinal, immune, and cardiovascular). These transmembrane receptors form folded accordion-like structures embedded in the cell membrane with loops of protein on the inside (intracellular loops) and outside (extracellular loops) of the membrane. The second extracellular loop is fundamental for ligand-induced activation, with key interactions of R274/Y278/D280/W283.
Sources: en.wikipedia.org
== Micellization and phase transitions == An important characteristic of poloxamer solutions is their temperature dependent self-assembling and thermo-gelling behavior. Concentrated aqueous solutions of poloxamers are liquid at low temperature and form a gel at higher temperature in a reversible process. The transitions that occur in these systems depend on the polymer composition (molecular weight and hydrophilic/hydrophobic molar ratio). At low temperatures and concentrations (below the critical micelle temperature and critical micelle concentration) individual block copolymers (unimers) are present in solution. Above these values, aggregation of individual unimers occurs in a process called micellization. This aggregation is driven by the dehydration of the hydrophobic polyoxypropylene block that becomes progressively less soluble as the polymer concentration or temperature increases. The aggregation of several unimers occurs to minimize the interactions of the PPO blocks with the solvent. Thus, the core of the aggregates is made from the insoluble blocks (polyoxypropylene) while the soluble portion (polyoxyethylene) forms the shell of the micelles.
==== Limitation on overall itemized deductions ==== Itemized deductions are reduced by 2/37 of the lesser of the amount of the itemized tax deductions or the taxable income that is within the 37%-rate marginal tax bracket. As an exception, the qualified business income deduction under 26 U.S.C. § 199A is not subject to the limitation.
=== Industry sectors === Singapore is the world's third-largest foreign exchange centre, sixth-largest financial centre, second-largest casino gambling market, third-largest oil-refining and trading centre, largest oil-rig producer and hub for ship repair services, and largest logistics hub. The economy is diversified, with its top contributors being financial services, manufacturing, and oil-refining. Its main exports are refined petroleum, integrated circuits, and computers, which constituted 27% of the country's GDP in 2010. Other significant sectors include electronics, chemicals, mechanical engineering, and biomedical sciences. Singapore was ranked 5th in the Global Innovation Index in 2025. In 2019, there were more than 60 semiconductor companies in Singapore, which together constituted 11% of the global market share. The semiconductor industry alone contributes around 7% of Singapore's GDP. Singapore's largest companies are in the telecommunications, banking, transportation, and manufacturing sectors, many of which started as state-run statutory corporations and have since been publicly listed on the Singapore Exchange. Such companies include Singapore Telecommunications (Singtel), Singapore Technologies Engineering, Keppel Corporation, Oversea-Chinese Banking Corporation (OCBC), Development Bank of Singapore (DBS), and United Overseas Bank (UOB). In 2011, after the 2008 financial crisis, OCBC, DBS and UOB were ranked by Bloomberg Businessweek as the world's first, fifth, and sixth strongest banks in the world, respectively.
Nidanas 1, 2 and 3 which cast beings downward into the whirl of transmigration Nidanas 4 to 7 represent what undergoes transmigration, "the aspects of the person undergoing phenomenal life" (Wayman). Nidanas 8, 9, 10 produce new karma Nidanas 11 and 12 are the fruits or results of karma produced previously According to Gombrich, the "contorted" three lives interpretation is rendered unnecessary by the analysis provided by Jurewicz and other scholars which show that the 12 link chain is a composite list.
Sources: en.wikipedia.org
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.
It is registered as a medicine in Russia and has been used clinically there for decades. No regulatory agency in Western Europe or North America has approved it for any indication.
Semax corresponds to the four-to-ten fragment of adrenocorticotropic hormone. Because it omits the first three residues, it lacks the adrenal-stimulating action of the full hormone.
不是。Semax 是完全人工合成的七肽，自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10)，但序列经过了替换和延长。