Semax raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
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。
| 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 |
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。
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
=== Insulin resistance === Isoleucine, like other branched-chain amino acids, is associated with insulin resistance: higher levels of isoleucine are observed in the blood of diabetic mice, rats, and humans. In diet-induced obese and insulin resistant mice, a diet with decreased levels of isoleucine (with or without the other branched-chain amino acids) results in reduced adiposity and improved insulin sensitivity. Reduced dietary levels of isoleucine are required for the beneficial metabolic effects of a low protein diet. In humans, a protein restricted diet lowers blood levels of isoleucine and decreases fasting blood glucose levels. Mice fed a low isoleucine diet are leaner, live longer, and are less frail. In humans, higher dietary levels of isoleucine are associated with greater body mass index.
Senate delegation to visit China during the second Trump presidency, with the group traveling to Beijing and Shanghai to meet Chinese officials and visit technology companies. On 7 May, Chinese premier Li Qiang and National People's Congress Standing Committee chairman Zhao Leji separately met with the delegation in Beijing.
C-4 or Composition C-4 is a common variety of the plastic explosive family known as Composition C, which uses RDX as its explosive agent. C-4 is composed of explosives, plastic binder, plasticizer to make it malleable, and usually a marker or odorizing taggant chemical. C-4 has a texture similar to modelling clay and can be molded into any desired shape. C-4 is relatively insensitive and can be detonated only by the shock wave from a detonator or blasting cap. A similar British plastic explosive, also based on RDX but with a plasticizer different from that used in Composition C-4, is known as PE-4 (Plastic Explosive No. 4).
Sources: en.wikipedia.org
Notable HPTLC devices such as the Linomat 5 and the Automatic TLC Sampler 4 (ATS 4) by CAMAG function very similarly by having the automated 'spray-on' sample application technique. This automated 'spray-on' technique is useful to overcome the uncertainty in droplet size and position when the sample is applied to the TLC plate by hand. Additionally, automation provides high resolution and narrow bands since the solvent evaporates immediately as the sample makes contact with the plate. One approach to automation has been the use of piezoelectric devices and inkjet printers for applying the sample. Alternatively, the Nanomat 4 and ATS 4 by CAMAG are manually operated where the sample is applied via spot application using a capillary pipette. Upon chromatographic detection, HPTLC plates are usually developed in saturated twin-trough chambers with filter paper for optimal outcomes. However, flat-bottom chambers and horizontal-development chambers are also used for specific compounds. A general mechanism for the HPTLC device goes as follows. A fitted filter paper is placed in the rear trough of the chamber and the mobile phase is poured through the rear trough to ensure complete solvent absorption of the filter paper. The chamber is then tilted to ~45° so both troughs are equal in solvent volume and left alone to equilibrate for ~20 mins. Finally, the HPTLC plate is placed in the chamber to develop. Between each sample reading, the mobile phase and filter paper are changed to ensure the best outcomes.
During the 2010s, the Moroccan mafia was widely talked about in Dutch and Belgian politics. After the assassination of Derk Wiersum, a lawyer with information about Ridouan Taghi, Geert Wilders expressed his discontent in the Dutch parliament.
Two hundred and eighty-six scholars, artists, and scientists received Guggenheim Fellowships in 1970. $2,605,000 was disbursed between the recipients, who were chosen from an applicant pool of 2,313. Of the 81 universities represented, University of California, Berkeley had the most winners on its faculty (23), with Harvard University (17) claiming second and University of California, Los Angeles (10) claiming third.
Sources: en.wikipedia.org
where quantities in square brackets represent the molar concentrations of the species at equilibrium. For example, a hypothetical weak acid having Ka = 10−5, the value of log Ka is the exponent (−5), giving pKa = 5. For acetic acid, Ka = 1.8 x 10−5, so pKa is 4.7. A lower Ka corresponds to a weaker acid (an acid that is less dissociated at equilibrium). The form pKa is often used because it provides a convenient logarithmic scale, and a lower pKa corresponds to a stronger acid.
== Restoration after root canal treatment == After root canal treatment, the tooth is usually restored with a crown or a filling to protect it and restore function. In restorative dentistry, root canal treatment is considered alongside fillings, crowns, bridges, Dentures, and implants. After restoration, such a tooth can continue to function like a normal tooth.
=== Nitrides, azides, and nitrido complexes === Nitrogen bonds to almost all the elements in the periodic table except the first two noble gases, helium and neon, and some of the very short-lived elements after bismuth, creating an immense variety of binary compounds with varying properties and applications. Many binary compounds are known: with the exception of the nitrogen hydrides, oxides, and fluorides, these are typically called nitrides. Many stoichiometric phases are usually present for most elements (e.g. MnN, Mn6N5, Mn3N2, Mn2N, Mn4N, and MnxN for 9.2 < x < 25.3). They may be classified as "salt-like" (mostly ionic), covalent, "diamond-like", and metallic (or interstitial), although this classification has limitations generally stemming from the continuity of bonding types instead of the discrete and separate types that it implies. They are normally prepared by directly reacting a metal with nitrogen or ammonia (sometimes after heating), or by thermal decomposition of metal amides:
At 7pm on January 9, Urquía Carreño called Viñas Alonso and asked if they could meet in private. Urquía Carreño brought Airán Cervera with him, and they met in Viñas Alonso's home. Urquía Carreño and Airán Cervera then informed him about the missing safe. Viñas Alonso said: "This is a very serious situation.... Did you call the police?" Urquía Carreño replied that he had not, to avoid damaging Freemasonry's image. Viñas Alonso asked why Urquía Carreño waited four days to inform him that the safe was missing, but Airán Cervera assured him that they could have the money replaced by March. "We talk all the time. You should have told me. You should have gone to the police... Just leave. I need time to think. This is all very serious." Viñas Alonso said. Urquía Carreño and Airán Cervera left. At 9pm on January 9, Viñas Alonso deliberated scheduling an urgent meeting of the Board of Trustees for the next day. He called Urquía Carreño to discuss this option. "Don't do that, it won't benefit anyone," Urquía Carreño said. Viñas Alonso then insisted the meeting would take place at 4pm. At the emergency meeting of the Board of Trustees on January 9, the Board of Trustees was made aware of the situation, and Viñas Alonso made a motion for a vote on two proposals. The first was to go immediately to the National Revolutionary Police and file a police report. The second proposal was to draft a report that would be sent out to all Cuban Freemasons detailing the events which took place.
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。