Everything below concerns semax. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-09-25. Numbers and descriptions here follow the published literature rather than marketing material.
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。
Semax is normally supplied as a lyophilized powder, and that form is the most stable. Suppliers commonly recommend storage at -20 °C in a desiccated container protected from light, with short-term handling at room temperature limited to weighing and transfer. Powder that has absorbed moisture degrades faster, so vials should be warmed to ambient temperature before opening to prevent condensation on the contents. Hygroscopic behavior is typical of short hydrophilic peptides, and humidity control matters more than temperature alone for long-term retention.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
| Property | Value | Notes |
|---|---|---|
| 化学类别 | 合成七肽 | ACTH(4-10) 结构类似物 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | 单字母写作 MEHFPGP |
| 分子量 | 约 813.9 Da | 随确切形式和盐型略有变化 |
| 常见同义词 | ACTH(4-10) 类似物 | 俄语文献称 Семакс |
| 开发来源 | 俄罗斯 | 二十世纪八十年代 |
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。
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
In the 2011–12 season, a coaching change by appointing Christian Streich, with the club finishing 12th. Under Christian Streich, the 2012–13 Bundesliga season saw the club finish in fifth place, their best league standing since 1994–95. The fifth-place finish secured a position in the 2013–14 UEFA Europa League. Had Freiburg defeated Schalke 04 on the final matchday of the season, Freiburg would have advanced further in the league table against Schalke and qualified for the UEFA Champions League for the first time in club history. The 1–2 defeat to Schalke, however, saw Schalke secure fourth place in the league and qualify for the tournament instead. During the 2012–13 season, Freiburg also advanced to the semi-finals of the DFB-Pokal for the first time in the club's history, but lost to local rivals VfB Stuttgart 1–2, and missed the chance to play Bayern Munich in the final. In the 2014–15 season, after six years in the top flight, Freiburg was relegated to the 2. Bundesliga by a single point after a final-day defeat at Hannover 96. This was despite beating Bayern Munich in the second-last game. In the following season, however, the club earned its fifth promotion to the Bundesliga, with two matches to spare. The first season back in the Bundesliga saw them end seventh. This saw Freiburg qualify for the Europa League, as German cupwinners Borussia Dortmund were already qualified for the Champions League. The side were eliminated in the third qualification round against NK Domžale from Slovenia. Freiburg stayed in the top flight, finishing 15th.
During the 1970s, the expansion of Arby's took place at a rate of 50 stores per year. During this time it created several menu items, including the Beef 'n Cheddar, Jamocha Shakes, chicken sandwiches, curly fries, and two signature sauces: Arby's Sauce and Horsey Sauce. Baked potatoes were added to the menu in 1985. Curly fries were initially introduced as Curly-Q Fries in 1988. It became the first restaurant in the fast food industry to offer a complete "lite" menu in 1991 with several sandwiches and salads under 300 calories and 94 percent fat-free. The family-owned business tried converting into a public company in 1970 by offering the sale of stock, but the IPO never went through when the stock market subsequently fell. Arby's filed for reorganization with the United States bankruptcy court in February 1971, owing to a large number of debts accrued in expansion, as well as a nationwide recession and relatively high price point compared to other fast-food chains of the time. In 1976, the family sold the company to RC Cola for $18 million and Leroy Raffel remained as CEO until his retirement three years later. In 1984, Victor Posner obtained Arby's via a hostile takeover of its then parent Royal Crown through his DWG Corporation. Nine years later, with a new owner of DWG Corporation and a new name, Triarc Companies, Inc., a former PepsiCo executive, Don Pierce, was brought in to "resurrect" Arby's. With $100 million additional funding, Pierce moved to a new "Roast Town" concept, similar in format to Boston Market, in 1996.
A reliable means of propulsion for the submerged vessel was only made possible in the 1880s with the advent of the necessary electric battery technology. The first electrically powered boats were built by Isaac Peral y Caballero in Spain (who built Peral), Dupuy de Lôme (who built Gymnote) and Gustave Zédé (who built Sirène) in France, and James Franklin Waddington (who built Porpoise) in England. Peral's design featured torpedoes and other systems that later became standard in submarines.
Sources: en.wikipedia.org
When B cells and T cells are activated by a pathogen, memory B-cells and T- cells develop, and the primary immune response results. Throughout the lifetime of an animal, these memory cells will "remember" each specific pathogen encountered, and can mount a strong secondary response if the pathogen is detected again. The primary and secondary responses were first described in 1921 by English immunologist Alexander Glenny although the mechanism involved was not discovered until later. This type of immunity is both active and adaptive because the body's immune system prepares itself for future challenges. Active immunity often involves both the cell-mediated and humoral aspects of immunity as well as input from the innate immune system.
Sendai virus (family Paramyxoviridae) has a linear, single-stranded, negative-sense, nonsegmented RNA genome. The viral RdRp consists of two virus-encoded subunits, a smaller one P and a larger one L. Testing different inactive RdRp mutants with defects throughout the length of the L subunit in pairwise combinations, restoration of viral RNA synthesis was observed in some combinations. This positive L–L interaction is referred to as intragenic complementation and indicates that the L protein is an oligomer in the viral RNA polymerase complex.
35. Adv Gerontol. 2006;19:66-71. [Influence of light regimens, melatonin, and epitalon on amylase activity in the pancreas and small intestine in rats of different age]. [Article in Russian] Svechkina EB, Tiutiunnik NN, Vinogradova IA. The study shows that keeping rats in different light modes has a different impact on pancreatic and intestine amylase activity and has its peculiarities in regard of age as well as geroprotectors' influence on it. Melatonin use entails pancreatic amylase activity increase in mature animals in natural light of the North-West of Russia (NL) and 24-hour constant light (LD) and on the contrary amylase activity drops in case of using epitalon. Simultaneously, the enzyme activity in young and old rats under LD, melatonin and epitalon decreases. Intestine amylase activity influenced by both preparations rises in NL and drops in LD mode with respect to the control group.
Sources: en.wikipedia.org
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。
Semax 被描述为 ACTH(4-10) 的结构类似物，两者共享部分序列特征。它保留了该片段的部分神经相关活性方向，但去除了完整片段带来的激素释放效应。二者并非同一物质，也不能互相替代。
加入的 Pro-Gly-Pro 三肽被普遍认为能提升分子对蛋白水解酶的稳定性。这种设计让短肽在体内维持时间更长。具体延长的程度以及不同组织中是否一致，文献中仍存在不同报告。
Each freeze-thaw cycle can degrade a fraction of the peptide and promote aggregation. Dividing a stock solution into single-use volumes removes repeated cycling as a variable. It also limits the time a thawed solution spends at room temperature.