This is a working overview of ACTH 片段, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-09-26 and is reviewed periodically as new material appears.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
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。
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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。
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
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.
Peter Joseph Moloney (29 June 1891, Penetanguishene, Ontario – 12 August 1989, Toronto, Ontario) was a Canadian chemist. He is known for his work on developing vaccines against diphtheria and tetanus, purifying insulin preparations for clinical use, demonstrating antibodies against insulin in humans and animals, and developing sulfated insulin preparations for the treatment of diabetics with insulin resistance. He also invented a quick-acting pH electrode and helped to develop an antiserum that was used in WW II for protection against gas gangrene.
Smaller communities of Hokkien speakers also existed, and many villages hosted more than one ethnolinguistic group. Today, communities of speakers of other Chinese varieties (such as Teochew, Sze Yap, Hokkien, and Shanghainese) also live in Hong Kong. Southeast Asian languages such as Tagalog and Malay-Indonesian speaking communities also live in Hong Kong. Other minority languages with significant speaker bases in Hong Kong include French, Dutch, German, Italian, Spanish, Portuguese, Arabic, Hindustani, Japanese, and Korean, among others.
If the size of a detector is very small compared to the distance traveled by the light, any light that is scattered by a particle, either in the forward or backward direction, will not strike the detector. (Bouguer was studying astronomical phenomena, so this condition was met.) In such cases, a plot of
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Warren and Senator Richard Blumenthal of Connecticut asked the Department of Justice and Securities and Exchange Commission to investigate whether senior bank executives had violated any laws. Senator John Kennedy of Louisiana criticized regulators for lax oversight of the bank. The Bank Policy Institute, which represents large banks, contended that the failures of SVB and Signature Bank were primarily caused by failures of management and supervision, rather than regulation, and stressed its members' resiliency. Several Republicans and conservative commentators argued that the bank failed because it was "woke" and distracted by its workforce diversity efforts, which are typical of mid-sized and large banks in the U.S. Florida Governor Ron DeSantis, Representative Marjorie Taylor Greene of Georgia, and Tucker Carlson tied the bank's failure to its diversity, equity, and inclusion (DEI) program. Greene and Representative James Comer of Kentucky cited the bank's environmental, social, and corporate governance investment program. Senator Tim Scott of South Carolina implied that the San Francisco Fed overlooked risks at the bank due to a shared focus on climate change. Andy Kessler suggested that the presence of minorities and military veterans on the bank's board of directors served as a distraction. The New York Post blamed the DEI efforts of a manager at the UK subsidiary for the risks that arose in the U.S.
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Humped animals appear in some cave paintings, which is of interest to paleontologists, who can use such depictions to better understand what extinct fauna looked like. Some cave paintings depict woolly mammoths as being humped, which is corroborated by the humps present on frozen specimens. Similarly, the cave bear is depicted as having a shoulder hump in some French cave paintings. Because of how prominently humps are drawn, it has been theorized that ancient painters used the hump as the starting point when drawing. Humps may not be accurately created in taxidermy. William Temple Hornaday lamented that when stuffing plains bison, there is a tendency to make the hump "a huge, thick, rounded mass like the hump of a dromedary," as opposed to the "high and sharp" muscle hump that bison actually have.
== Context == Selection acts on variation in phenotypes, which are often the result of mutations in protein-coding genes. The genetic code is written in DNA sequences as codons, groups of three nucleotides. Each codon represents a single amino acid in a protein chain. However, there are more codons (64) than amino acids found in proteins (20), so many codons are effectively synonyms. For example, the DNA codons TTT and TTC both code for the amino acid Phenylalanine, so a change from the third T to C makes no difference to the resulting protein. On the other hand, the codon GAG codes for Glutamic acid while the codon GTG codes for Valine, so a change from the middle A to T does change the resulting protein, for better or (more likely) worse, so the change is not a synonym. These changes are illustrated in the tables below. The Ka/Ks ratio measures the relative rates of synonymous and nonsynonymous substitutions at a particular site.
== Development == Half-Life 2: Deathmatch was started as a test while Half-Life 2 was being developed. Designer Adrian Finol wanted to know what it was like to use the gravity gun in a multiplayer setting, creating a build that showcased Half-Life 2 multiplayer. Scott Dalton created a map and the two played in the office, and Gabe Newell asked to be shown the product. Finol pushed for multiplayer so mod makers could access the tools to create their own levels. Upon the release and subsequent critical reception of Half-Life 2, reviewers expressed disappointment with the game's lack of multiplayer. Two weeks after the initial release of Half-Life 2, Valve revealed and released Half-Life 2: Deathmatch on Steam. Deathmatch was released simultaneously with the Source SDK as a means of promoting game modifications built upon the platform. Post-release, the game was supported with new maps from Valve as well as updates to the game and its engine. Valve's The Orange Box originally did not include Half-Life 2: Deathmatch, however, the game was upgraded to use the Orange Box version of the Source engine in September 2010. Valve announced a free promotional offer on January 10, 2008, which allowed NVIDIA graphics card users to download and play Half-Life 2: Deathmatch along with Portal: First Slice, Half-Life 2: Lost Coast, and Peggle Extreme. In September 2010, the game was released via Steam for OS X. A Linux version came more than two years later, in March 2013.
It functions specifically function in the G protein signaling pathway through G protein, which is a transmembrane protein that causes the cascade phosphorylation. It is located throughout the entire length of intestine while PHI is mostly concentrated in the colon region.
Sources: en.wikipedia.org
The WHO urban air quality database estimated Delhi's mean annual PM 10 levels in 2010 as 286 μg /m3 and London as 23 μg /m3. In 2014, the database estimated Delhi's annual mean PM 2.5 particulate matter levels in 2013 as 156 μg /m3 whereas, London have only 8 μg /m3 in 2010 but the nitrogen dioxide in London breach the European Union's standard. In 2013, the annual mean nitrogen dioxide level in London was estimated as 58 μg /m3 but the save and "threshold limit value" is 40 μg /m3. In March 2015, Brussels took the United Kingdom into court for breaching emissions limits of nitrogen dioxide at its coal-fired Aberthaw power stations in Wales. The plant operated under a permit allowing emissions of 1200 mg/Nm3, which is more than twice the 5 mg/Nm3 limit specified in the EU's large combustion plant directive.
== Bacteriophage T4 DNA polymerase == Bacteriophage (phage) T4 gene 43 encodes the phage's DNA polymerase replicative enzyme. Temperature-sensitive (ts) gene 43 mutants have been identified that have an antimutator phenotype, that is a lower rate of spontaneous mutation than wild type. Studies of one of these mutants, tsB120, showed that the DNA polymerase specified by this mutant copies DNA templates at a slower rate than the wild-type polymerase. However, the 3' to 5' exonuclease activity was no higher than wild-type. During DNA replication the ratio of nucleotides turned over to those stably incorporated into newly formed DNA is 10 to 100 times higher in the case of the tsB120 mutant than in wild-type. It was proposed that the antimutator effect may be explained by both greater accuracy in nucleotide selection and an increased efficiency of removal of noncomplementary nucleotides (proofreading) by the tsB120 polymerase. When phage T4 virions with a wild-type gene 43 DNA polymerase are exposed to either ultraviolet light, which introduces cyclobutane pyrimidine dimer damages in DNA, or psoralen-plus-light, which introduces pyrimidine adducts, the rate of mutation increases. However, these mutagenic effects are inhibited when the phage's DNA synthesis is catalyzed by the tsCB120 antimutator polymerase, or another antimutator polymerase, tsCB87. These findings indicate that the level of induction of mutations by DNA damage can be strongly influenced by the gene 43 DNA polymerase proofreading function.
Representative James Talarico legislative website Talarico for Texas U.S. Senate campaign website Financial information (federal office) at the Federal Election Commission Profile at Vote Smart Appearances on C-SPAN
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
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。