The short version of aliquot fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-10-21. Anything still debated is marked as such rather than presented as settled.
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.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
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。
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
At the time, these findings were seen as a confirmation of Franz Joseph Gall's theory that language was localized and that certain psychological functions were localized in specific areas of the cerebral cortex. The localization of function hypothesis was supported by observations of epileptic patients conducted by John Hughlings Jackson, who correctly inferred the organization of the motor cortex by watching the progression of seizures through the body. Carl Wernicke further developed the theory of the specialization of specific brain structures in language comprehension and production. In 1894, neurologist and psychiatrist Edward Flatau published a human brain atlas "Atlas of the Human Brain and the Course of the Nerve-Fibres" which consisted of long-exposure photographs of fresh brain sections. In 1897, Charles Scott Sherrington introduced the name "synapse" for the connection between neurons.
An unexpected series of experimental results for the rate of decay of heavy highly charged radioactive ions circulating in a storage ring provoked theoretical activity in an effort to find a convincing explanation. The rates of weak decay of two radioactive species with half-lives of about 40 s and 200 s were reported to have a significant oscillatory modulation, with a period of about 7 s. The reported phenomenon is known as the GSI anomaly, as the storage ring is a facility at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany. As the decay process produces an electron neutrino, some of the proposed explanations for the observed rate oscillation invoked neutrino properties. Initial ideas related to flavour oscillation met with skepticism. A 2016 proposal involved mass differences between neutrino mass eigenstates. In a follow-up study published in 2019, measurements of about 9,000 electron-capture decays of hydrogen-like promethium-142 ions showed no periodic modulation. The results were consistent with exponential decay.
ISBN 0841911789. Smith, Helmut Walser (September 2017). "Review of Detlev Peukert und die NS-Forschung edited by Rüdiger Hachtmann & Sven Reichardt". German History. 35 (3): 485–486. doi:10.1093/gerhis/ghx032. Zimmermann, Michael (Spring 1991). "Detlev Peukert 1950-1990". History Workshop. 31 (31): 245–248. doi:10.1093/hwj/31.1.245.
After the start of the civil war, various new telecommunications companies began to spring up and compete to provide missing infrastructure. Funded by Somali entrepreneurs and backed by expertise from China, South Korea and Europe, these nascent telecommunications firms offer affordable mobile phone and Internet services that are not available in many other parts of the continent. Customers can conduct money transfers (such as through the popular Dahabshiil) and other banking activities via mobile phones, as well as easily gain wireless Internet access. After forming partnerships with multinational corporations such as Sprint, ITT and Telenor, these firms now offer the cheapest and clearest phone calls in Africa. These Somali telecommunication companies also provide services to every city and town in Somalia. There are presently around 25 mainlines per 1,000 persons, and the local availability of telephone lines (tele-density) is higher than in neighbouring countries; three times greater than in adjacent Ethiopia. Prominent Somali telecommunications companies include Golis Telecom Group, Hormuud Telecom, Somafone, Nationlink, Netco, Telcom and Somali Telecom Group. Hormuud Telecom alone grosses about US$40 million a year. Despite their rivalry, several of these companies signed an inter-connectivity deal in 2005 that allows them to set prices, maintain and expand their networks, and ensure that competition does not get out of control. The state-run Somali National Television is the principal national public service TV channel.
Sources: en.wikipedia.org
=== Selected papers === Hydrolysis of tri-tert-butylaluminum: The First Structural Characterization of Alkylalumoxanes [(R2Al)2O]n and (RAlO)n. Journal of the American Chemical Society (1993) Three-coordinate Aluminum is not a Prerequisite for Catalytic Activity in the Zirconocene-alumoxane Polymerization of Ethylene. Journal of the American Chemical Society (1995) From Minerals to Materials: Synthesis of Alumoxanes from the Reaction of Boehmite with Carboxylic Acids. Journal of Materials Chemistry (1995) Single Wall Carbon Nanotube Amplification: En route to a Type-specific Growth Mechanism. Journal of the American Chemical Society (2006) Effects of Mechanical Flexion on the Penetration of Fullerene Amino Acid-derivatized Peptide Nanoparticles Through Skin. Nano Letters (2007) Synthesis, Characterization, and Carbon Dioxide Absorption of Covalently Attached Polyethyleneimine-functionalized Single-wall Carbon Nanotubes. ACS Nano (2008) High-yield Organic Dispersions of Unfunctionalized Graphene.
CPC Scientific Group was founded in 2001, and the US company established in 2005 by Shawn Lee, Ph.D., and began by supplying research-grade custom peptides, catalog peptides, and Fmoc-protected amino acids. In 2006, the company opened a GMP (Good Manufacturing Practice) facility in Hangzhou, China to support the production of peptides for clinical use. The Hangzhou site underwent its first inspection by the U.S. Food and Drug Administration (FDA) in 2011, after which CPC Scientific began supplying pharmaceutical-grade peptides to clients in the United States. On March 17, 2016, the company passed a fourth FDA inspection. In 2024, the company completed a fifth U.S. FDA inspection and was also inspected by Australia’s Therapeutic Goods Administration (TGA). In 2025, CPC Scientific obtained ISO 22716:2007 Cosmetic GMP certification for the manufacture of peptide ingredients for cosmetic applications. CPC Scientific is part of Medtide Inc., which was listed on the Main Board of the Hong Kong Stock Exchange on June 30, 2025 (Stock Code: 03880).
There is currently no use for any isotope of berkelium outside basic scientific research. Berkelium-249 is a common target nuclide to prepare still heavier transuranium elements and superheavy elements, such as lawrencium, rutherfordium and bohrium. It is also useful as a source of the isotope californium-249, which is used for studies on the chemistry of californium in preference to the more radioactive californium-252 that is produced in neutron bombardment facilities such as the HFIR. A 22 milligram batch of berkelium-249 was prepared in a 250-day irradiation and then purified for 90 days at Oak Ridge in 2009. This target yielded the first 6 atoms of tennessine at the Joint Institute for Nuclear Research (JINR), Dubna, Russia, after bombarding it with calcium ions in the U400 cyclotron for 150 days. This synthesis was a culmination of the Russia-US collaboration between JINR and Lawrence Livermore National Laboratory on the synthesis of elements 113 to 118 which was initiated in 1989.
Migalastat, sold under the brand name Galafold, is a medication used for the treatment of Fabry disease, a rare genetic disorder. Migalastat is an alpha-galactosidase A (alpha-Gal A) pharmacological chaperone. It was developed by Amicus Therapeutics. The most common adverse drug reactions include headache, nasal and throat irritation (nasopharyngitis), urinary tract infection, nausea, and fever (pyrexia). Migalastat was authorized for medical use in the European Union in May 2016, and approved for medical use in the United States in August 2018. The US Food and Drug Administration considers it to be a first-in-class medication.
=== Absorption and transport === Inadequate absorption of vitamin B12 may be related to coeliac disease. Intestinal absorption of vitamin B12 requires successively three different protein molecules: haptocorrin, intrinsic factor and transcobalamin II.
Sources: en.wikipedia.org
An independent panel upholds the Parliamentary Commissioner for Standards' decision that Scott Benton, MP for Blackpool South, should face a 35-day suspension from Parliament. The suspension will now be voted on by MPs and could trigger another by-election. Heather Woodbridge, aged 29, is appointed as leader of Orkney Islands Council, becoming Scotland's youngest council leader and the first woman to lead Orkney Islands Council. 21 February – An Opposition day House of Commons debate calling for a ceasefire in Gaza descends into chaos after Speaker Sir Lindsay Hoyle breaks with Parliamentary convention to allow a vote on a Labour amendment calling for an "immediate humanitarian ceasefire" over the scheduled SNP motion calling for an "immediate ceasefire". The decision leads to protests from both Conservative and SNP MPs, who walk out of the House, leaving Labour's motion to be nodded through when the other two parties do not take part in the vote. Amid calls for his resignation, Hoyle says that he allowed the House to vote on the Labour motion so MPs could express their view on "the widest range of propositions", and to protect MPs' safety. King Charles III is seen back at work and meeting Prime Minister Rishi Sunak, the first time he has been seen back at work since his cancer diagnosis. Senior civil servant Sarah Munby writes to the Business Secretary to reject allegations by former Post Office chairman Henry Staunton that he was told to delay compensation payments to victims of the Horizon scandal.
=== Mechanical parts === Polyimide powder can be used to produce parts and shapes by sintering technologies (hot compression molding, direct forming, and isostatic pressing). Because of their high mechanical stability even at elevated temperatures they are used as bushings, bearings, sockets or constructive parts in demanding applications. To improve tribological properties, compounds with solid lubricants like graphite, PTFE, or molybdenum sulfide are common. Polyimide parts and shapes include P84 NT, VTEC PI, Meldin, Vespel, and Plavis.
This proved that in aqueous solution, nobelium is most stable in the divalent state when strong oxidizers are absent. Later experimentation in 1974 showed that nobelium eluted with the alkaline earth metals, between Ca2+ and Sr2+. Nobelium is the only known f-block element for which the +2 state is the most common and stable one in aqueous solution. This occurs because of the large energy gap between the 5f and 6d orbitals at the end of the actinide series. It is expected that the relativistic stabilization of the 7s subshell greatly destabilizes nobelium dihydride, NoH2, and relativistic stabilisation of the 7p1/2 spinor over the 6d3/2 spinor mean that excited states in nobelium atoms have 7s and 7p contribution instead of the expected 6d contribution. The long No–H distances in the NoH2 molecule and the significant charge transfer lead to extreme ionicity with a dipole moment of 5.94 D for this molecule. In this molecule, nobelium is expected to exhibit main-group-like behavior, specifically acting like an alkaline earth metal with its ns2 valence shell configuration and core-like 5f orbitals. Nobelium's complexing ability with chloride ions is most similar to that of barium, which complexes rather weakly. Its complexing ability with citrate, oxalate, and acetate in an aqueous solution of 0.5 M ammonium nitrate is between that of calcium and strontium, although it is somewhat closer to that of strontium. The standard reduction potential of the E°(No3+→No2+) couple was estimated in 1969 to be between +1.4 and +1.5 V; it was later found in 2009 to be only about +0.75 V.
=== Doping in sport === Selegline is on the World Anti-Doping Agency (WADA)'s list of prohibited substances. It is classified as a "stimulant" in this list, along with various amphetamines, methylphenidate, adrenergic sympathomimetics, modafinil, and other agents. A review of the pharmacology of WADA prohibited substances noted that although selegiline is classified as a stimulant in the WADA prohibited substances list and stimulants can enhance physical performance, selegiline was seemingly included in the list not because of any short-term stimulant effects of its own, but rather because it metabolizes into small amounts of levomethamphetamine and levoamphetamine and can produce false positives for amphetamines on drug tests. In any case, levomethamphetamine and levoamphetamine are catecholamine releasing agents and can produce sympathomimetic and psychostimulant effects with sufficiently high exposure. Such actions may have performance-enhancing effects.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
Solid peptide is best kept frozen at about minus 20 degrees Celsius in a sealed container with desiccant. It should be allowed to reach room temperature before opening to prevent condensation. Repeated warming and cooling of the same vial is discouraged.