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 2025-09-08 and is reviewed periodically as new material appears.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity specification | ≥ 95 % of peak area by HPLC | Some suppliers quote 98 % or higher |
| Identity confirmation | Mass spectrometry (electrospray or MALDI) | Observed mass is compared with the calculated mass |
| Common analytical method | Reversed-phase HPLC on a C18 column | Acetonitrile and water gradients with trifluoroacetic acid |
| Primary degradation route | Oxidation of the methionine residue | Yields a sulfoxide that separates cleanly on chromatography |
| Storage of dissolved material | Aliquoted and frozen at −20 °C or below | Single-use aliquots avoid repeated temperature cycling |
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
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。
Douglas Carlyle Cameron (born March 22, 1957) is an American engineer, inventor, and investor. He is a senior managing director for the U.S.-China Green Fund. He is on the board of the Foundation for Food and Agriculture Research (FFAR) and is a technical and business advisor to organizations including the VTT (Finland), and the Center for Bioenergy Innovation (USA).
== Louisiana Secretary of Revenue (1996–1999) == Following his first stint in state government, Kennedy returned to private law practice until 1996. That year, he was appointed secretary of the state Department of Revenue in the cabinet of Governor Mike Foster. Despite having political differences with Kennedy during his time in Roemer's administration, Foster selected Kennedy for the position and later endorsed him for the U.S. Senate. Kennedy stepped down as secretary in April 1999 and was replaced by Brett Crawford.
The Russian Empire organized its Cossacks into several voiskos (hosts), which lived along the Russian border and internal borders between Russian and non-Russian peoples. Each host originally had its own leadership, ranks, regalia, and uniforms. By the late 19th century, ranks were standardized following the example of the Imperial Russian Army. The ranks and insignia were kept after the 1988 law allowing the hosts to reform, and the 2005 law legally recognizing the hosts as a combat service. They are given below as per all military tickets that are standard for the Russian Army.
Sources: en.wikipedia.org
the presence of acid (primarily the secreted HCl) that leads to a low pH in the stomach (a case of negative feedback) somatostatin also inhibits the release of gastrin, along with secretin, GIP (gastroinhibitory peptide), VIP (vasoactive intestinal peptide), glucagon and calcitonin.
=== Synthesis === The chemical synthesis of LSD has been described. It is commonly synthesized by reacting diethylamine with an activated form of lysergic acid. Activating reagents include phosphoryl chloride and peptide coupling reagents. Lysergic acid is made by alkaline hydrolysis of lysergamides like ergotamine, a substance usually derived from the ergot fungus on agar plate. Lysergic acid can also be produced synthetically, although these processes are not used in clandestine manufacture due to their low yields and high complexity. Albert Hofmann synthesized LSD in the following manner: (1) hydrazinolysis of ergotamine into D- and L-isolysergic acid hydrazide, (2) separation of the enantiomers with di-(p-toluyl)-D-tartaric acid to get D-isolysergic acid hydrazide, (3) enantiomerization into D-lysergic acid hydrazide, (4) substitution with HNO2 to D-lysergic acid azide and (5) finally substitution with diethylamine to form D-lysergic acid diethylamide. The precursor for LSD, lysergic acid, has been produced by GMO baker's yeast.
Generation of Neutralizing Human Monoclonal Antibodies Against a Therapeutic Target from the Alloy Therapeutics Mouse Generation Using a Molecular Modeling Platform to Guide Therapeutic Antibody Discovery Optimization of Therapeutic Discovery Strategies for Human Antibody Transgenic Animal Platforms Development of Antibody and PK, and ADA Assays for a Cystine Knot Fusion Protein A Rapid, High-Throughput Recombinant Antibody Expression System for Therapeutic Antibody Discovery and Validation Generation of Agonist and Antagonist Human Monoclonal Antibodies Against an Immune Checkpoint Target from the H2L2 Mouse Generation and Selection of Human Monoclonal Antibodies from the OmniRat Therapeutic Antibody Discovery at Antibody Solutions using the OmniAb Platform Development of human antibodies to human vascular endothelial growth factor -C (VEGF-C) and -D (VEGF-D) Obtaining Antibodies to Difficult Membrane Targets through DNA and Cell Immunization Next-Generation Therapeutic Antibody Discovery from Single B-cells Generation and Selection of Human Monoclonal Antibodies from the H2L2 Mouse Generation of Antibodies to Difficult Membrane Protein Targets Development of Antibodies and ELISAs to measure Free and Total Obiltoxaximab (ETI-204) in the Presence of Anthrax Protective Antigen PA63 Discovery of Therapeutic Antibodies to Difficult Membrane Proteins
Tool use by animals may indicate different levels of learning and cognition. The sea otter uses rocks as essential and regular parts of its foraging behavior (smashing abalone from rocks or breaking open shells), with some populations spending 21% of their time making tools. Other tool use, such as chimpanzees using twigs to "fish" for termites, may be developed by watching others use tools and may even be a true example of animal teaching. Tools may even be used in solving puzzles in which the animal appears to experience a "Eureka moment". Other mammals that do not use tools, such as dogs, can also experience a Eureka moment. Brain size was previously considered a major indicator of the intelligence of an animal. Since most of the brain is used for maintaining bodily functions, greater ratios of brain to body mass may increase the amount of brain mass available for more complex cognitive tasks. Allometric analysis indicates that mammalian brain size scales at approximately the 2⁄3 or 3⁄4 exponent of the body mass. Comparison of a particular animal's brain size with the expected brain size based on such allometric analysis provides an encephalization quotient that can be used as another indication of animal intelligence. Sperm whales have the largest brain mass of any animal on earth, averaging 8,000 cubic centimetres (490 cu in) and 7.8 kilograms (17 lb) in mature males. Self-awareness appears to be a sign of abstract thinking. Self-awareness, although not well-defined, is believed to be a precursor to more advanced processes such as metacognitive reasoning.
Sources: en.wikipedia.org
Meanwhile, Duterte's ICC withdrawal was challenged before the Supreme Court by three petitions filed by the Philippine Coalition for the ICC, the Integrated Bar of the Philippines, and opposition senators; though the Court in March 2021 ultimately dismissed all three cases on the grounds that the petitioners were unable to establish legal standing to challenge the ICC withdrawal, the court ruled that the president has no "unbridled authority" to withdraw from treaties. The ICC, on September 16, 2021, eventually authorized a formal investigation into the war on drugs in the Philippines, focusing on crimes committed between 2016 and March 2019. In response, the Philippine government in November 2021 requested a deferral of the probe, which was suspended by the ICC to assess the request. Four days before Duterte left office, however, ICC prosecutor Karim Ahmad Khan requested the pre-trial chamber of the ICC to immediately resume the investigation after concluding that the deferral request was "not warranted". The succeeding Marcos administration initially declined to allow any ICC probe in the country due to sovereignty issues; however, due to tensions between the Duterte and Marcos political families, the Marcos administration is seen as increasingly open to cooperating with the ICC. Duterte stated he remained unfazed at the threat of arrest, saying he would rather "die first" before facing a foreign court. Salvador Panelo, who served as Duterte's chief legal counsel, alleged that Duterte's political opponents were using the ICC as a "political and propaganda apparatus".
After the Japanese surrender to the Allies on 15 August 1945, Singapore fell into a brief state of violence and disorder; looting and revenge killings particularly against collaborators were widespread. British, Australian, and Indian troops led by Lord Louis Mountbatten returned to Singapore to receive the formal surrender of Japanese forces in the region from General Seishirō Itagaki on behalf of General Hisaichi Terauchi on 12 September 1945. Meanwhile, Tomoyuki Yamashita was tried by a US military commission for war crimes, but not for crimes committed by his troops in Malaya or Singapore. He was convicted and hanged in the Philippines on 23 February 1946. Much of the infrastructure in Singapore had been destroyed during the war, including those needed to supply utilities. A shortage of food led to malnutrition, disease, and rampant crime and violence. A series of strikes in 1947 caused massive stoppages in public transport and other services. However, by late 1947 the economy began to recover, facilitated by a growing international demand for tin and rubber. The failure of Britain to successfully defend its colony against the Japanese changed its image in the eyes of Singaporeans. The British Military Administration ended on 1 April 1946, and Singapore became a separate crown colony in its own right, as the Straits Settlements were formally dissolved that year. In July 1947, an Executive and Legislative Council (LegCo) were reconstituted and the election of six members of the LegCo was scheduled for 1948.
== Further reading == Brandoni, Diego; Scillato Yané, Gustavo J.; Miño Boilini, Ángel R.; Favotti, Emmanuel (2016). "Los Tardigrada (Mammalia, Xenarthra) de Argentina: diversidad, evolución y biogeografía" (PDF). Contribuciones del MACN. _: 263–274. Retrieved 2018-10-08. Cuvier, G. (1796): Notice sur le squelette d'une très grande espèce de quadrupède inconnue jusqu'à présent, trouvé au Paraguay, et déposé au cabinet d'histoire naturelle de Madrid. Magasin encyopédique, ou Journal des Sciences, des Lettres et des Arts (1): 303–310; (2): 227–228. De Iuliis, G. & Cartelle, C. (1999): A new giant megatheriine ground sloth (Mammalia: Xenarthra: Megatheriidae) from the late Blancan to early Irvingtonian of Florida. Zool. J. Linn. Soc. 127(4): 495–515. Harrington, C.R. (1993): Yukon Beringia Interpretive Center - Jefferson's Ground Sloth. Retrieved 2008-JAN-24. Hogan, C.M. (2008): Cueva del Milodon, Megalithic Portal. Retrieved 2008-APR-13 Kurtén, Björn and Anderson, Elaine (1980): Pleistocene Mammals of North America. Columbia University Press, New York. ISBN 0-231-03733-3 McKenna, Malcolm C. & Bell, Susan K. (1997): Classification of Mammals Above the Species Level. Columbia University Press, New York. ISBN 0-231-11013-8 Nowak, R.M. (1999): Walker's Mammals of the World (Vol. 2). Johns Hopkins University Press, London. White, J.L. (1993): Indicators of locomotor habits in Xenarthrans: Evidence for locomotor heterogeneity among fossil sloths. Journal of Vertebrate Paleontology, 13(2): 230–242. White, J.L.; MacPhee, R.D.E. (2001).
Sources: en.wikipedia.org
Suppliers normally quote a percentage of total chromatographic peak area, most often from reversed-phase HPLC. That figure says nothing about what the remaining percentage contains, and it depends on the detection wavelength used. A mass spectrometry result is a separate and stronger check on identity.
The methionine residue at the start of the chain is vulnerable to oxidation, producing a sulfoxide variant. Amide bonds can also hydrolyze, though more slowly under neutral conditions. Cold storage, oxygen exclusion and minimization of freeze-thaw cycles slow both processes but do not stop them.
A purity number on a certificate does not establish that a powder is the same product as a registered nasal medicine. Counter-ion content, residual solvents and peptide-related impurities may differ between the two. Independent verification is the only way to narrow that gap.
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.