Everything below concerns nootropic. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-07-11. Where a claim depends on a specific study, the study is described rather than over-claimed.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
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.
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。
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 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 |
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
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。
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。
=== Chairmen === Chairman of the Anti-Fascist Council of People's Liberation of Bosnia and Herzegovina Vojislav Kecmanović (25 November 1943 – 26 April 1945) Chairmen of the Presidium of the People's Assembly Vojislav Kecmanović (26 April 1945 – November 1946) Đuro Pucar (November 1946 – September 1948) Vlado Šegrt (September 1948 – March 1953) Chairmen of the People's Assembly Đuro Pucar (December 1953 – June 1963) Ratomir Dugonjić (June 1963 – July 1967) Džemal Bijedić (1967 – July 1971) Hamdija Pozderac (July 1971 – May 1974) Chairmen of the Presidency Ratomir Dugonjić (May 1974 – April 1978) Raif Dizdarević (April 1978 – April 1982) Branko Mikulić (April 1982 – 26 April 1984) Milanko Renovica (26 April 1984 – 26 April 1985) Munir Mesihović (26 April 1985 – April 1987) Mato Andrić (April 1987 – April 1988) Nikola Filipović (April 1988 – April 1989) Obrad Piljak (April 1989 – 20 December 1990) Alija Izetbegović (20 December 1990 – 8 April 1992)
In 2013, researchers demonstrated graphene's high mobility in a detector that allows broad band frequency selectivity ranging from the THz to IR region (0.76–33 THz) A separate group created a terahertz-speed transistor with bistable characteristics, which means that the device can spontaneously switch between two electronic states. The device consists of two layers of graphene separated by an insulating layer of boron nitride a few atomic layers thick. Electrons move through this barrier by quantum tunneling. These new transistors exhibit negative differential conductance, whereby the same electric current flows at two different applied voltages. In June, an 8 transistor 1.28 GHz ring oscillator circuit was described. The negative differential resistance experimentally observed in graphene field-effect transistors of conventional design allows for construction of viable non-Boolean computational architectures. The negative differential resistance—observed under certain biasing schemes—is an intrinsic property of graphene resulting from its symmetric band structure. The results present a conceptual change in graphene research and indicate an alternative route for graphene applications in information processing. In 2013 researchers created transistors printed on flexible plastic that operate at 25 gigahertz, sufficient for communications circuits and that can be fabricated at scale. The researchers first fabricated non-graphene-containing structures—the electrodes and gates—on plastic sheets.
Macrophages can also endocytose IgG-bound latent TGF-β complexes that are secreted by plasma cells and then release active TGF-β into the extracellular fluid. Among its key functions is regulation of inflammatory processes, particularly in the gut. TGF-β also plays a crucial role in stem cell differentiation as well as T-cell regulation and differentiation. Because of its role in immune and stem cell regulation and differentiation, it is a highly researched cytokine in the fields of cancer, autoimmune diseases, and infectious disease. The TGF-β superfamily includes endogenous growth inhibiting proteins; an increase in expression of TGF-β often correlates with the malignancy of many cancers and a defect in the cellular growth inhibition response to TGF-β. Its immunosuppressive functions then come to dominate, contributing to oncogenesis. The dysregulation of its immunosuppressive functions is also implicated in the pathogenesis of autoimmune diseases, although their effect is mediated by the environment of other cytokines present.
By the early modern period, Neo-Latin had become the lingua franca of science, medicine, legal discourse, theology, and education in Europe. Over time, the use of Latin continued where international communication with specialist audiences was paramount. Later, where some of the discourse moved to French, English or German, translations into Latin would allow texts to cross language boundaries, while authors in countries with much smaller language populations or less known languages would tend to continue to compose in Latin. Latin's dominance over medicine began to change in the late seventeenth century, as philosophers and others began to write in their native language first, afterwards translating into Latin for international audiences. In the early part of the 1700s, Latin was still making a significant contribution to academic publishing, but was no longer dominant. Examples of modern medical dictionaries include Mosby's Dictionary of Medicine, Nursing & Health Professions, Stedman's, Taber's, and Dorland's.
=== Anions and cations === Cations including sodium, potassium, calcium, and magnesium are common in industrial water supplies. Common anions include chloride, sulfate, and bicarbonate. Several methods are used to remove ions from input water supplies including reverse osmosis, distillation, and/or ion exchange. Distillation can be used to remove non-volatile metal cations and was historically used for water purification. However, distillation is energy-intensive compared to the combination of reverse osmosis and ion exchange which are more common in modern systems.
Sources: en.wikipedia.org
AaH I is a hemorrhagic toxin which means it causes internal bleeding by damaging blood vessels. AaH I damages the walls of capillaries, causes them to leak blood internally, leading to death. Hemorrhagic toxins are common among other snake venoms as well like rattlesnakes and the western diamondback. There are four different types of AaH in Agkistrodon acutus venom, with AaH I being the strongest hemorrhagic one. Its proteolytic activity was sensitive to pH where it was 100 times stronger in weak alkaline conditions at pH 7.5. This is referring to the break down of proteins through the enzyme proteases. Aah I has three disulfide connections at Cys117-Cys197, Cys159-Cys181 and Cys157-Cys164. There is also one calcium ion, zinc ion, and three histidine zinc ligation in the structure. Each member of the metzincins has a zinc ion in its active site. Metzincins family is metalloproteinases that use a zinc ion in the enzymatic reaction. The zinc binding in AaH I is tetrahedral, three imidazole nitrogen atoms of histidine and one oxygen atom. It is unknown whether this oxygen atom is a water molecule or a hydroxide ion. A calcium ion occurs on the surface of the AaH I molecule opposite to the active-site cleft and close to the crossover point of the N-terminal and the C-terminal segment. Its position close to the C terminus, this calcium ion in the multi-domain parent structure could well play an important role in stabilizing and tightening the segment connecting the proteolytic domain with the succeeding disintegrin domain.
These compounds are often not detected by routine toxicology tests and can be masked by the presence of a known compound in the same sample. As new compounds are discovered, known spectra are determined and entered into the databases that can be downloaded and used as reference standards. Laboratories also tend to keep in-house databases for the substances they find locally.
== Modern use == Commercially available hardtack is a significant source of food energy in a small, durable package. A store-bought 24-gram cracker can contain 100 calories (20 percent from fat) and 2 grams of protein.
== Side effects == Common side effects are peeling, itching, redness, dryness, burning, and dermatitis. Benzoyl peroxide bleaches hair, clothes, towels, bedclothing, and the like. Prolonged exposure to natural or artificial sun light (UV rays) is not recommended because the gel may cause photosensitivity. Irritation due to benzoyl peroxide can be reduced by avoiding harsh facial cleansers and wearing sunscreen prior to sun exposure. Clinical studies have shown systemic absorption of clindamycin through topical application, in some cases leading to diarrhea, bloody diarrhea, and colitis. Reports of anaphylaxis were also seen. However, the sources of these reports were personal accounts without controls and of an unknown population, thus it is difficult to attribute their cause to the clindamycin/benzoyl peroxide gel.
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。