heptapeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-04-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
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。
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
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.
| 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 |
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
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.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
=== Private versus state-owned slaves === Slaves have been owned privately by individuals but have also been under state ownership. For example, the kisaeng were women from low castes in pre modern Korea, who were owned by the state under government officials known as hojang and were required to provide entertainment to the aristocracy. In the 2020s, in North Korea, Kippumjo ("Pleasure Brigades") are made up of women selected from the general population to serve as entertainers and as concubines to the rulers of North Korea. "Tribute labor" is compulsory labor for the state and has been used in various iterations such as corvée, mit'a and repartimiento. The internment camps of totalitarian regimes such as the Nazis and the Soviet Union placed increasing importance on the labor provided in those camps, leading to a growing tendency among historians to designate such systems as slavery. A combination of these include the encomienda where the Spanish Crown granted private individuals the right to the free labour of a specified number of natives in a given area. In the "Red Rubber System" of both the Congo Free State and French ruled Ubangi-Shari, labour was demanded as taxation; private companies were conceded areas within which they were allowed to use any measures to increase rubber production. Convict leasing was common in the Southern United States where the state would lease prisoners for their free labour to companies.
"Took up the cooperative movement" at its annual convention in 1919. Moved into its new 4-story building in the West End at the corner of Leverett and Ashland Street and moved in on November 13, 1920. The building contained the group's offices, cooperative grocery, creamery, shoe and dry goods store, and printing plant. The "Co-operative Wholesale Society" consisting of the "Finnish, Lithuanian, and Italian Co-operative of New England" had its offices and warehouse in this building as well. Jewish Progressive Order - Headquartered in Philadelphia. Supported the Palestine Restoration Fund by a "shekel tax" of 25 cents per member. Jewish National Workers Alliance Order of Brith Abraham - Founded in New York in 1859. Originally restricted to Reform Jews. Female lodges, consisting of the female relatives of members of the order, could be formed with the sanction of the Grand Lodge and could elect one of the Past Presidents of the male lodges as their officers. In 1899 there were 11,000 regular members and 1,000 members of the female lodges. 8,000 regular members and three-fifths of the 160 lodges were located in New York City. In 1923 it had 198 lodges, 15,152 benefit members, and 195 social members. It had 8,000 members when it became defunct in 1927. Headquarters in 1923 located at 266-268 Grand Street New York City. The ceremony of the order was calculated to inculcate the values of harmony, wisdom, and justice. The order's emblem was an "interlaced triangle" with a representation of Abraham about to sacrifice Jacob.
=== Prevention and other services === Aside from diagnosing and treating acute conditions, the Internist may also assess disease risk and recommend preventive screening and intervention. Some of the tools available to the Internist include genetic evaluation. Internists also routinely provide pre-operative medical evaluations including individualized assessment and communication of operative risk. Training the next generation of internists is an important part of the profession. As mentioned above, post-graduate medical education is provided by licensed doctors as part of accredited education programs that are usually affiliated with teaching hospitals. Studies show that there are no differences in patient outcomes in teaching versus non-teaching facilities. Medical research is an important part of most post-graduate education programs, and many licensed doctors continue to be involved in research activities after completing post-graduate training.
Sources: en.wikipedia.org
In particular, Maricopa County has been targeted by conspiracy theorists for alleged irregularities in how the county voted in the 2020 presidential election; the county's ballots were audited by Republicans in 2021, finding no such claims of voter fraud. Ahead of the 2023 Philadelphia mayoral election and the Pennsylvania primary election, the account for the Philadelphia City Commissioners was unverified, leading to several verified accounts impersonating the commissioners. On May 22, an account aligned with the QAnon conspiracy theory posted an image generated by artificial intelligence that seemingly depicted an explosion near the Pentagon. The fake image was amplified by the Russian propaganda television network RT and the far-right blog Zero Hedge. A verified account posing as Bloomberg News then posted the claim accompanied by several other verified accounts. The S&P 500 fell sharply as a result of the news before rebounding. Several Indian news outlets, including Zee News and Republic TV, aired false reports about the supposed explosion.
=== Harvey's controversy === Due to a trademark dispute with Canada's Harvey's burger chain, the Hardee's brand name cannot be used in the country. Instead, CKE Restaurants operates exclusively under the Carl's Jr. banner.
== Clinical significance == Patients with salt-sensitive hypertension have higher plasma ET-1. Endothelin-1 receptor antagonists (Bosentan) are used in the treatment of pulmonary hypertension. Use of these antagonists prevents pulmonary arterial constriction and thus inhibits pulmonary hypertension. As of 2020, the role of endothelin-1 in affecting lipid metabolism and insulin resistance in obesity mechanisms was under clinical research.
Sources: en.wikipedia.org
==== Privatization of waterways in the North, Recife Metro and COMPESA ==== In June 2025, the Lula government, despite strong popular opposition, supported the privatization of the Recife Metro and of the COMPESA (the Pernambuco sanitation company responsible for water supply in the state), measures announced by the governor of Pernambuco, Raquel Lyra. In both cases, the BNDES, under the leadership of Aloizio Mercadante, organized the studies to make the privatization process feasible and will also conduct the bidding procedures. In late May, the chief of staff, Rui Costa, had already confirmed that the Recife Metro would be privatized, continuing a process initiated in 2019 during the Jair Bolsonaro administration. The argument used by the government to justify the measure is that the metro system generates only financial losses. The decision prompted protests in Pernambuco, especially in Recife. In addition, in September 2025 the government included the waterway of the Madeira River and the waterways of the Tocantins and Tapajós rivers in the National Privatization Program (PND), a measure that also received criticism. During the 2022 presidential campaign and in government, Lula strongly criticized the privatizations carried out by the previous administration and even promised that the Recife Metro would not be privatized. The privatization measures were criticized especially by the more radical sectors of the Brazilian left, which also criticized the government's attempt to soften the term “privatization” by presenting them as “concessions”.
== Structure == Peptoid oligomers are known to be conformationally unstable, due to the flexibility of the main-chain methylene groups and the absence of stabilizing hydrogen bond interactions along the backbone. Nevertheless, through the choice of appropriate side chains it is possible to form specific steric or electronic interactions that favour the formation of stable secondary structures like helices, especially peptoids with C-α-branched side chains are known to adopt structure analogous to polyproline I helix. Different strategies have been employed to predict and characterize peptoid secondary structure, with the ultimate goal of developing fully folded peptoid protein structures The cis/trans amide bond isomerization still leads to a conformational heterogeneity which doesn’t allow for the formation of homogeneous peptoid foldamers. Nonetheless, scientists were able to find trans-inducer N-Aryl side chains promoting polyproline type II helix, and strong cis-inducer such as bulky naphtylethyl and tert-butyl side chains. It was also found that n→π* interactions can modulate the ratio of cis/trans amide bond conformers, until reaching a complete control of the cis conformer in the peptoid backbone using a functionalizable triazolium side chain.
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{\displaystyle {\frac {[\mathrm {cyt~c_{red}} ]}{[\mathrm {cyt~c_{ox}} ]}}=\left({\frac {[\mathrm {NADH} ]}{[\mathrm {NAD} ]^{+}}}\right)^{\frac {1}{2}}\left({\frac {[\mathrm {ADP} ][\mathrm {P_{i}} ]}{[\mathrm {ATP} ]}}\right)K_{\mathrm {eq} }}
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。
It consists mainly of animal experiments and small clinical reports, with much of the clinical material published in Russian-language journals. Large independent trials are scarce. Separating reliable effects from chance findings is consequently difficult.