Everything below concerns Semax. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-04-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
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。
== Side effects == Common side effects of apomorphine include nausea and vomiting, particularly when starting treatment, and injection site reactions, including bruising, subcutaneous nodules, and rarely necrosis or abscesses. Other common side effects include somnolence, dizziness, and falls. Clinical reviews note that while nausea is frequently reported early during apomorphine therapy, tolerability may improve with a lower starting dose and continued use. Less common side effects include dyskinesia, orthostatic hypotension, hallucinations or psychotic-like behavior, syncope, hemolytic anemia, impulse control disorders, dose-dependent QT interval prolongation, peripheral edema, and priapism. Adverse effects are more common with continuous subcutaneous apomorphine infusion than intermittent treatment.
In this application, ion-exchange resins are used to remove poisonous (e.g. copper) and hazardous metal (e.g. lead or cadmium) ions from solution, replacing them with more innocuous ions, such as sodium and potassium, in the process cation and anion exchange resins are used to remove dissolved ions from the water. Few ion-exchange resins remove chlorine or organic contaminants from water – this is usually done by using an activated charcoal filter mixed in with the resin. There are some ion-exchange resins that do remove organic ions, such as MIEX (magnetic ion-exchange) resins. Domestic water purification resin is not usually recharged – the resin is discarded when it can no longer be used. These ion-exchange skids that are used and sized for 10 ML/day per bead can have cost upwards of US$1.5–2.5 million when implemented for industrial water treatment. Water of highest purity is required for many uses ranging from electronics to scientific experiments, as well as the production of superconductors, and within the nuclear industry, among others. Such water is produced using ion-exchange processes or combinations of membrane and ion-exchange methods. This method can prove to be expensive as the secondary waste handling cost can run on average US$0.10–0.20 per cubic meter.
chemistry The scientific discipline that studies chemical substances, compounds, and molecules composed of atoms of various chemical elements, as well as their compositions, structures, properties, behaviors, and the changes they undergo during reactions with other substances.
in the range of 108 – 1010 M−1 s−1. These enzymes are so efficient they effectively catalyse a reaction each time they encounter a substrate molecule and have thus reached an upper theoretical limit for efficiency (diffusion limit); and are sometimes referred to as kinetically perfect enzymes. But most enzymes are far from perfect: the average values of
In some aquatic insects, the tracheae exchange gas through the body wall directly, in the form of a gill, or function essentially as normal, via a plastron. Note that despite being internal, the tracheae of arthropods are lined with cuticular tissue and are shed during moulting (ecdysis).
Sources: en.wikipedia.org
Most aptamers are based on a specific oligomer sequence of 20-100 bases and 3-20 kDa. Some have chemical modifications for functional enhancements or compatibility with larger engineered molecular systems. DNA, RNA, XNA, and peptide aptamer chemistries can each offer distinct profiles in terms of shelf stability, durability in serum or in vivo, specificity and sensitivity, cost, ease of generation, amplification, and characterization, and familiarity to users. Typically, DNA- and RNA-based aptamers exhibit low immunogenicity, are amplifiable via Polymerase Chain Reaction (PCR), and have complex secondary structure and tertiary structure. DNA- and XNA-based aptamers exhibit superior shelf stability. XNA-based aptamers can introduce additional chemical diversity to increase binding affinity or greater durability in serum or in vivo. As 22 genetically encoded and over 500 naturally occurring amino acids exist, peptide aptamers, as well as antibodies, have much greater potential combinatorial diversity per unit length relative to the 4 nucleic acids in DNA or RNA. Chemical modifications of nucleic acid bases or backbones increase the chemical diversity of standard nucleic acid bases. Split aptamers are composed of two or more DNA strands that are pieces of a larger parent aptamer that has been broken in two by a molecular nick. The ability of each component strand to bind targets will depend on the location of the nick, as well as the secondary structures of the daughter strands. The presence of a target molecule supports the joining of DNA fragments.
== Other animals == Animal models of androgenic alopecia occur naturally and have been developed in transgenic mice; chimpanzees (Pan troglodytes); bald uakaris (Cacajao rubicundus); and stump-tailed macaques (Macaca speciosa and M. arctoides). Of these, macaques have demonstrated the greatest incidence and most prominent degrees of hair loss. Baldness is not a trait unique to human beings. One possible case study is about a maneless male lion in the Tsavo area. The Tsavo lion prides are unique in that they frequently have only a single male lion with usually seven or eight adult females, as opposed to four females in other lion prides. Male lions may have heightened levels of testosterone, which could explain their reputation for aggression and dominance, indicating that lack of mane may at one time have had an alpha correlation. Although nonhuman primates do not go bald, their hairlines do undergo recession. In infancy, the hairline starts at the top of the supraorbital ridge, but slowly recedes after puberty to create the appearance of a small forehead.
=== EC 1.21.3 With oxygen as acceptor === EC 1.21.3.1: isopenicillin-N synthase EC 1.21.3.2: columbamine oxidase EC 1.21.3.3: reticuline oxidase EC 1.21.3.4: sulochrin oxidase ((+)-bisdechlorogeodin-forming) EC 1.21.3.5: sulochrin oxidase ((-)-bisdechlorogeodin-forming) EC 1.21.3.6: aureusidin synthase EC 1.21.3.7: tetrahydrocannabinolic acid synthase EC 1.21.3.8: cannabidiolic acid synthase EC 1.21.3.9: now classified as EC 1.21.98.2, dichlorochromopyrrolate synthase
== Structure == The body of the penis is suspended from the pubic symphysis by the suspensory ligament, part of the deep fascia arising from the anterior surface of the symphysis. It has two surfaces; the dorsal and the ventral or urethral. The penile raphe runs on its ventral surface. The body is surrounded by a bi-layered model of tunica albuginea in which a distal ligament buttresses the glans penis and plays an integral role in the penile fibroskeleton, and the structure is called "os analog", a term coined by Geng Long Hsu in the Encyclopedia of Reproduction. The human penis differs from those of most other mammals in having no baculum (or erectile bone), relying exclusively on engorgement with blood to reach its erect state; the loss of the baculum in the human lineage has been linked to changes in mating pattern. A shallow groove, which marks their junction on the upper surface lodges the deep dorsal vein of the penis, which is flanked by a pair of cavernosal veins of the penis, while a deeper and wider groove between them on the surface below contains the corpus spongiosum. The body is ensheathed by fascia, which includes tunica albuginea, Buck's fascia, dermis, and skin.
Sources: en.wikipedia.org
Still, the index closed at its all-time high of 24,121.74, for its first close above 24,000 points. The SENSEX closed at 25,019.51, for its first close above the 25,000 milestone on 5 June 2014 26,000, 7 July 2014- The SENSEX crossed record 26,000 level for the first time on 7 July 2014 and reached its peak of 26,123.55, before closing slightly lower at 26,100.08, in anticipation of strong reformatory budget by the new government. 27,000, 2 September 2014 - The SENSEX closed at 27,019.39, for its first close above the 27,000 level, on 2 September 2014. This is the sixth 1000-point milestone the index has crossed in 2014, tying a record set in 2007. 28,000, 5 November 2014 - The SENSEX crossed 28,000 mark, on 5 November 2014. One week later, on 12 November 2014, the index would close above the milestone for the first time. This is the seventh 1000-point milestone the index has crossed in 2014, breaking the six 1000-point record set in 2007. 29,000, 23 January 2015 - BSE Sensex today set a new high of 29,408 points and all-time closing high of 29,278.84, up 272.82 points 30,000, 4 March 2015 - The Sensex breaches 30000 mark following steps taken by the Reserve Bank of India in cutting the repo rates. 26 April 2017 - The SENSEX closed at 30,133.35, for its first close above the 30,000 level. 31,000, 26 May 2017- The SENSEX crossed record 31,000 level for the first time on 26 May 2017 and reached its peak of 31,074.07, before closing slightly lower at 31,028.21. 32,000, 13 July 2017 - The SENSEX closed at 32,037.38, for its first close above the 32,000 level, on 13 July 2017.
Hydrogen sulfide is about one-half as toxic as hydrogen cyanide, and intoxicates by the same mechanism (inhibition of the respiratory enzyme cytochrome oxidase), though hydrogen sulfide is less likely to cause sudden poisonings from small inhaled amounts (near its permissible exposure limit (PEL) of 20 ppm) because of its disagreeable odor. However, its presence in ambient air at concentration over 100–150 ppm quickly deadens the sense of smell, and a victim may breathe increasing quantities without noticing until severe symptoms cause death. Dissolved sulfide and hydrosulfide salts are toxic by the same mechanism.
In February 2002, the Senate Select Committee on Intelligence and the House Permanent Select Committee on Intelligence formed a joint inquiry into the performance of the U.S. Intelligence Community. Their 832-page report released in December 2002 detailed failings of the FBI and CIA to use available information, including about terrorists the CIA knew were in the United States, to disrupt the plots. The joint inquiry developed its information about possible involvement of Saudi Arabian government officials from non-classified sources. The Bush administration demanded 28 related pages remain classified. In December 2002, the inquiry's chair Bob Graham revealed in an interview that there was "evidence that there were foreign governments involved in facilitating the activities of at least some of the terrorists in the United States." Victim families were frustrated by the unanswered questions and redacted material from the congressional inquiry and demanded an independent commission. September 11 victim families, members of Congress and the Saudi Arabian government are still seeking the release of the documents. In June 2016, CIA chief John Brennan said that he believes 28 redacted pages of a congressional inquiry into 9/11 will soon be made public, and that they will prove that the government of Saudi Arabia had no involvement in the September 11 attacks. In September 2016, Congress passed the Justice Against Sponsors of Terrorism Act that would allow relatives of victims of the September 11 attacks to sue Saudi Arabia for its government's alleged role in the attacks.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.