If you have been reading about Neurotrophic signalling and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-09-19. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
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 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。
The Cherokee Nation (Cherokee: ᏣᎳᎩᎯ ᎠᏰᎵ, romanized: Tsalagihi Ayeli or ᏣᎳᎩᏰᎵ, Tsalagiyehli) is the largest of three federally recognized Cherokee tribes in the United States. Headquartered in Tahlequah, Oklahoma, the nation had 477,673 enrolled citizens as of 2026 (including 289,619 living in Oklahoma), making it one of the largest tribal nations in the country. The tribe includes people descended from members of the Old Cherokee Nation who relocated, due to increasing pressure, from the Southeast to Indian Territory and Cherokee who were forced to relocate on the Trail of Tears. The tribe also includes descendants of Cherokee Freedmen and the Natchez Nation. The nation operates under a constitution ratified in 2003, with executive, legislative, and judicial branches. In 2020 and 2021, federal and state courts affirmed that the Cherokee Nation's reservation—spanning 14 counties in northeastern Oklahoma—was never disestablished, restoring reservation status under the McGirt v. Oklahoma precedent. The nation has jurisdiction within this territory. The nation publishes the Cherokee Phoenix, the first Native American newspaper, and operates Cherokee language immersion schools. The Cherokee Nation has a reservation spanning 14 counties in the northeastern corner of Oklahoma. These are Adair, Cherokee, Craig, Delaware, Mayes, McIntosh, Muskogee, Nowata, Ottawa, Rogers, Sequoyah, Tulsa, Wagoner, and Washington counties.
In June 2011, the first location under the name Sonic Beach was opened in Homestead, Florida. A second location, opened in Fort Lauderdale, Florida, in November 2011, lacked drive-in stalls due to its beachside location. Both locations included outdoor seating and flatscreen televisions, but have since closed. A third location was opened in Miami Gardens. The fourth location was opened January 2014 in Lauderhill. Along with the traditional menu items, Sonic Beach offered several new items, including popcorn shrimp, Philly cheesesteaks, and pulled pork sandwiches. Sonic Beach serves beer and wine. Remaining locations have been rebranded under the traditional Sonic name, although retaining the Sonic Beach logo.
In Australia, New Zealand, and the United States, it is considered an analog of other illegal drugs and can be controlled under laws similar to the US Federal Analog Act. In September 2011, the US temporarily classified mephedrone as a Schedule I drug, with the classification taking effect in October 2011. This was made permanent in July 2012 with the passage of the Synthetic Drug Abuse Prevention Act (SDAPA).
In botany, apical dominance is the phenomenon whereby the main, central stem of the plant is dominant over (i.e., grows more strongly than) other side stems; on a branch the main stem of the branch is further dominant over its own side twigs. Plant physiology describes apical dominance as the control exerted by the terminal bud (and shoot apex) over the outgrowth of lateral buds.
=== Nuclear weapons === The Little Boy gun-type atomic bomb dropped on Hiroshima on August 6, 1945, was made of highly enriched uranium with a large tamper. A tamper is a layer of dense material surrounding the fissile material that delays its thermal expansion, keeping it supercritical for longer.The nominal spherical critical mass for an untampered 235U nuclear weapon is 56 kilograms (123 lb), which would form a sphere 17.32 centimetres (6.82 in) in diameter. The material must be 85% or more of 235U and is known as weapons grade uranium, though for a crude and inefficient weapon 20% enrichment is sufficient (called weapon(s)-usable). Even lower enrichment can be used, but this results in the required critical mass rapidly increasing. Use of a large tamper, implosion geometries, trigger tubes, polonium triggers, tritium enhancement, and neutron reflectors can enable a more compact, economical weapon using one-fourth or less of the nominal critical mass, though this would likely only be possible in a country that already had extensive experience in engineering nuclear weapons. Most modern nuclear weapon designs use plutonium-239 as the fissile component of the primary stage; however, HEU (highly enriched uranium, in this case uranium that is 20% or more 235U) is frequently used in the secondary stage as an igniter for the fusion fuel.
Sources: en.wikipedia.org
Azemiglitazone Ciglitazone Darglitazone Englitazone Netoglitazone Rivoglitazone Troglitazone (Rezulin), withdrawn due to increased incidence of drug-induced hepatitis. Balaglitazone (DRF-2593) – developed by Dr Reddy's Laboratories, discontinued during 2010-11 phase III trials as no better than available molecules. AS-605240 [648450-29-7] Leriglitazone: metabolite of pioglitazone Replacing one oxygen atom in a thiazolidinedione with an atom of sulfur gives a rhodanine.
Carbohydrate intermediates: In carbohydrate metabolism, intermediates such as glucose-6-phosphate and fructose-1,6-bisphosphate appear during glycolysis and gluconeogenesis. Amino acid intermediates: During amino acid biosynthesis or degradation, intermediates such as 2-oxoglutarate, pyruvate, or oxaloacetate are produced. These intermediates also link to the citric acid cycle. Lipid intermediates: Fatty acid metabolism involves intermediates like acyl-CoA derivatives during β-oxidation or fatty acid synthesis. Nucleotide intermediates: The metabolism of nucleotides, the building blocks of DNA and RNA, includes intermediates like inosine monophosphate (IMP), which is part of purine biosynthesis.
=== Polyaspartic acid === Polyaspartic acid, like IDS, binds to calcium and other heavy metal ions. It has many practical applications including corrosion inhibitors, wastewater additives, and agricultural polymers. A polyaspartic acid-based laundry detergent was the first laundry detergent in the world to receive the EU flower ecolabel. Calcium binding ability of polyaspartic acid has been exploited for targeting of drug-loaded nanocarriers to bone. Preparation of hydrogels based on polyaspartic acid, in a variety of physical forms ranging from fiber to particle, can potentially enable facile separation of the chelated ions from a solution. Therefore, despite being weaker than EDTA, polyaspartic acid can still be regarded as a viable alternative due to these features as well as biocompatibility and biodegradability.
Sauropsida/ Reptilia sensu lato †Araeoscelidia? †Parareptilia (polyphyletic) Diapsida/Neodiapsida †Drepanosauromorpha (placement uncertain) †Younginiformes (likely paraphyletic) †Ichthyosauromorpha (placement uncertain) †Thalattosauria (placement uncertain) †Sauropterygia (placement uncertain) †Choristodera (placement uncertain) †Kuehneosauridae (placement uncertain) Sauria/ Reptilia sensu stricto Lepidosauromorpha Lepidosauria Rhynchocephalia (tuatara) Squamata (lizards and snakes) Pantestudines (turtles and kin, placement uncertain) Archosauromorpha †Protorosauria (paraphyletic) †Rhynchosauria †Allokotosauria Archosauriformes †Phytosauria Archosauria Pseudosuchia Crocodilia (crocodilians) Avemetatarsalia/Ornithodira †Pterosauria Dinosauria †Ornithischia Saurischia (including birds (Aves))
Sources: en.wikipedia.org
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.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
Reversed-phase high-performance liquid chromatography is the standard method, with detection in the ultraviolet range. Peak area percentage yields a purity figure for the main component. Mass spectrometry is normally run alongside to confirm molecular identity.