A practical reference on Semax: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-07-24. Anything still debated is marked as such rather than presented as settled.
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。
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 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.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
| Property | Value | Notes |
|---|---|---|
| 结构类别 | 线性合成七肽 | 无环化结构,不含二硫键 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | N 端为甲硫氨酸 |
| 分子量 | 约 814 Da | 游离碱形式的计算值 |
| 外观 | 白色至类白色粉末 | 具吸湿性 |
| 溶解性 | 易溶于水 | 亦可溶于甲醇等极性溶剂 |
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
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.
Another disadvantage is that the input cell volume must be free of large cell clumps, which requires a pre-processing step (typically, by sonication). If cell clumps are not removed prior to processing, clogging of the valve occurs, and the unit must be cleaned thoroughly before the processing can continue. As a result, many protein purification labs find that the use of lysozyme and sonication is sufficient for routine bacterial protein expression. Other technologies, such as sonication and ball mills, are available for many of the same purposes, and have their own advantages and disadvantages. For example, sonication can generate high shear forces that break cellular DNA into small fragments. With a French press, the shear force can be carefully modulated by adjusting the piston pressure. The Press provides a single pass through the point of maximum shear force, limiting damage to delicate biological structures due to repeated shear, as occurs in other disruption methods.
== Specialized hardware for MD simulations == Anton – A specialized, massively parallel supercomputer designed to execute MD simulations MDGRAPE – A special purpose system built for molecular dynamics simulations, especially protein structure prediction
The Library of Congress is physically housed in three buildings on Capitol Hill and a conservation center in rural Virginia. The library's Capitol Hill buildings are all connected by underground passageways, so that a library user need pass through security only once in a single visit. The library also has off-site storage facilities in Maryland for less commonly requested materials.
Sources: en.wikipedia.org
=== Early detection === From May to August 1939 the LZ130 Graf Zeppelin II made flights along Britain's North Sea coast to investigate the 100-metre-high radio towers that were being erected from Portsmouth to Scapa Flow. LZ130 performed a series of radiometric tests and took photographs. German sources report the 12 m Chain Home signals were detected and suspected to be radar; however, the chief investigator was not able to prove his suspicions. Other sources are said to report different results. During the Battle of France, the Germans observed 12 m pulse signals on the western front without being able to recognize their origin and purpose. In mid-June 1940, the Deutsche Versuchsanstalt für Luftfahrt (DVL, German Aeronautic Research Institute) set up a special group under the direction of Professor von Handel and found out that the signals originated from the installations on the coast of the English Channel. Their suspicions were finally proven in the aftermath of the Battle of Dunkirk, when the British were forced to abandon a mobile gun-laying radar (GL Mk. I) station in Normandy. Wolfgang Martini's team of specialists was able to determine the operation of the system. GL was a rather crude system of limited effectiveness, and this led the Germans to have a dim view of British radar systems. However, an effective system requires more than just the radar; plotting and reporting are equally important, and this part of the system was fully developed in Chain Home.
== Books == Interstellar Grains (Chapman & Hall, London, 1967) Light Scattering Functions for Small Particles with Applications in Astronomy (Wiley, New York, 1973) Solid-State Astrophysics (ed. with D.J. Morgan) (D. Reidel, Boston, 1975) Interstellar Matter (with F.D. Khan & P.G. Mezger) (Swiss Society of Astronomy and Astrophysics, 1974) The Cosmic Laboratory (University College of Cardiff, 1975) Lifecloud: The Origin of Life in the Universe (with Fred Hoyle) (J.M. Dent, London, 1978) Diseases from Space (with Fred Hoyle) (J.M. Dent, London, 1979) Origin of Life (with Fred Hoyle) (University College Cardiff Press, 1979) Space Travellers: The Bringers of Life (with Fred Hoyle) (University College Cardiff Press, 1981) Evolution from Space (with Fred Hoyle) (J.M.
=== Separation methods === Few analytical detectors are truly specific for a single species; therefore some type of separation step is often necessary prior to detection. Moreover, separation allows for detection of multiple analytes within a single platform. Separations based upon planar chromatography (TLC) are perhaps the easiest to implement, since many μPADs are constructed with chromatographic paper. Typically, the separation channel is defined by wax-printing two hydrophobic barriers. Electrochemical detection is perhaps most common, likely due to its ease of implementation, although colorimetry, chemiluminscence, and mass spectral detection have also been used in conjunction with paper-based chromatographic separations. Despite the ease of implementation, planar chromatography is hindered by relatively low plate height (i.e., poor separation efficiency). Since the Chakraborty group demonstrated the feasibility of electrokinetic flow on μPADs, several applications of electrophoretic separations on μPADs have appeared in the literature. The Crooks group at UT-Austin successfully demonstrated that electrophoretic separations on μPADs could be accomplished at relatively low applied voltages compared to conventional electrophoretic devices due to the high field strengths that can be generated on very thin (180 μm) sheets of origami paper. Simpler separation methods can also be used on μPADs, for instance, the Henry group demonstrated the separation of plasma from whole blood using blood separation membranes.
Sources: en.wikipedia.org
This is based on the theory that uric acid is a powerful reducing agent and likely an important human antioxidant, in high concentration in blood. Thus, it has been suggested that free radicals, oxidative stress, and reactive oxygen species may play some role in the neuropathology of LNS. However, some evidence suggests against a role for uric acid in the neuropathology of Lesch–Nyhan syndrome:
==== Legion number and title (cognomen) ==== The numbering of the legions is confusing, since several legions shared the same number with others. Augustus numbered the legions he founded himself from I, but also inherited numbers from his predecessors. Each emperor normally numbered the legions he raised himself starting from I. However, even this practice was not consistently followed. For example, Vespasian kept the same numbers as before for legions he raised from disbanded units. Trajan's first legion was numbered XXX because there were 29 other legions in existence at the time it was raised; but the second Trajanic legion was given the sequential number II. XVII, XVIII and XIX, the numbers of the legions annihilated in the Teutoburg Forest, were never used again. (These three legions are without titles, suggesting that in disgrace their titles may have been deliberately forgotten or left unmentioned.) As a result of this somewhat chaotic evolution, the legion's title became necessary to distinguish between legions with the same number. Legions often carried several titles, awarded after successive campaigns, normally by the ruling emperor e.g. XII Fulminata was also awarded: paterna (fatherly), victrix (victorious), antiqua (venerable), certa constans (reliable, steadfast) and Galliena (Gallienus '). Pia fidelis (loyal and faithful), fidelis constans and others were titles awarded to several legions, sometimes several times to the same legion. Only the most established, commonly used titles are displayed on this table. The geographical titles indicate
If uncarboxylated prothrombin is being measured, this "Protein induced by Vitamin K Absence/antagonism (PIVKA-II)" is elevated in vitamin K deficiency. The test is used to assess risk of vitamin K–deficient bleeding in newborn infants. Osteocalcin is involved in calcification of bone tissue. The ratio of uncarboxylated osteocalcin to carboxylated osteocalcin increases with vitamin K deficiency. Vitamin K2 has been shown to lower this ratio and improve lumbar vertebrae bone mineral density. Matrix Gla protein must undergo vitamin K dependent phosphorylation and carboxylation. Elevated plasma concentration of dephosphorylated, uncarboxylated MGP is indicative of vitamin K deficiency.
Sources: en.wikipedia.org
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。
Semax 对应 ACTH 第 4 至第 10 位的片段,并在两端做了替换与延长,使其不再具备促肾上腺皮质激素的典型内分泌活性。这一改动同时改变了它在体内的稳定性与分布特征。
俄罗斯将其列为处方药物,需要医生开具处方。多数其他国家把它当作研究化合物,不能作为药品销售或宣称疗效。具体合法性取决于当地法规。
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.