The short version of synthetic heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-10-26 and is reviewed periodically as new material appears.
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.
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。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
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.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
, where Y is the weak hypercharge, which suppresses in a natural way the dimension 5 operators for the proton decay; or SU(5) in Split SUSY, where the symmetry is broken in the Standard Model at very high scales, with the Higgs mass parameter appearing finely-tuned in the low-energy effective theory. Among the many things, this theory predicts very high values for proton decay. SUSY SU(5) can be extended to include supergravity or extra dimensions. SUGRA SU(5) is a supersymmetric Grand Unified Theory based on the SU(5) gauge group within the framework of supergravity (SUGRA). Proton lifetime predictions have been computed in SUSY SU(5) from 5 dimensions (5D) models; and in string theory variants using D6-branes and orientifolds. As a final consideration, while Supersymmetry addresses many interesting theoretical issues, its prediction of the mass of the lightest supersymmetric particles at the TeV scale has been severely matched by the LHC results. Proton decay lifetime predictions are summarized in the following table. By comparing these predictions with the sensitivities expected from future experiments, it becomes clear that experiments will never be able to rule out the entire vast range of possible models. However, they will cover the bulk of the predicted lifetimes, offering both a strong discovery potential if GUT models are realized in nature and a remarkable capacity to constrain GUT model building.
The liver is the second largest organ (after the skin) and is an accessory digestive gland which plays a role in the body's metabolism. The liver has many functions some of which are important to digestion. The liver can detoxify various metabolites; synthesise proteins and produce biochemicals needed for digestion. It regulates the storage of glycogen which it can form from glucose (glycogenesis). The liver can also synthesise glucose from certain amino acids. Its digestive functions are largely involved with the breaking down of carbohydrates. It also maintains protein metabolism in its synthesis and degradation. In lipid metabolism it synthesises cholesterol. Fats are also produced in the process of lipogenesis. The liver synthesises the bulk of lipoproteins. The liver is located in the upper right quadrant of the abdomen and below the diaphragm to which it is attached at one part, the bare area of the liver. This is to the right of the stomach and it overlies the gall bladder. The liver synthesises bile acids and lecithin to promote the digestion of fat.
=== Pediatrics === Fever is often viewed with greater concern by parents and healthcare professionals than might be deserved, a phenomenon known as fever phobia, which is based in both caregiver's and parents' misconceptions about fever in children. Among them, many parents incorrectly believe that fever is a disease rather than a medical sign, that even low fevers are harmful, and that any temperature even briefly or slightly above the oversimplified "normal" number marked on a thermometer is a clinically significant fever. They are also afraid of harmless side effects like febrile seizures and dramatically overestimate the likelihood of permanent damage from typical fevers. The underlying problem, according to professor of pediatrics Barton D. Schmitt, is that "as parents we tend to suspect that our children's brains may melt." As a result of these misconceptions parents are anxious, give the child fever-reducing medicine when the temperature is technically normal or only slightly elevated, and interfere with the child's sleep to give the child more medicine.
== Companies and organizations == Companies such as Google, Microsoft and Amazon Web Services have offered platforms for deploying pre-built AI agents. Several protocols have been proposed for standardizing inter-agent communication, such as Agent2Agent, Gibberlink, and others. In December 2025, Linux Foundation announced the formation of the Agentic AI Foundation (AAIF), with the goal of ensuring that agentic AI evolves transparently and collaboratively.
Sources: en.wikipedia.org
Cilengitide, a cyclic pentapeptide (RGDfV), is an investigational drug intended to block the growth of new blood vessels in tumors by interfering with the activation of integrin αVβ3. This integrin is upregulated in tumor and activated endothelial cells. This and other anti-angiogenic therapies depend on cutting off the blood supply to the tumor micro-environment, leading to hypoxia and necrosis. Cilengitide has been evaluated for the treatment of glioblastoma, but, as is the case for other anti-angiogenic therapies, has not been shown to alter progression or improve survival either alone or in combination with standard treatments. CEND-1, also known as iRGD, is a cyclic peptide that homes to tumors via binding to integrin alpha V receptors. It also binds and activates neuropilin-1, leading to a temporary opening of the tumor and an enhanced delivery of anti-cancer agents into the tumor tissue. It is currently being tested in clinical trials in solid tumor patients.
== Health considerations == Normal functioning of the kidney, brain, liver, heart, and numerous other systems can be affected by uranium exposure because uranium is a toxic metal, although less toxic than other heavy metals, such as arsenic and mercury. It is weakly radioactive and is 'persistently' so because of its very long half-life. The Agency for Toxic Substances and Disease Registry states that: "to be exposed to radiation from uranium, you have to eat, drink, or breathe it, or get it on your skin." If DU particles do enter an individual, the type of danger presented—toxic vs. radiological—and the organ most likely to be affected depend on the solubility of the particles. In military conflicts involving DU munitions, the major concern is inhalation of DU particles in aerosols arising from the impacts of DU-enhanced projectiles with their targets. When depleted uranium munitions penetrate armor or burn, they create depleted uranium oxides in the form of dust that can be inhaled or contaminate wounds. The Institute of Nuclear Technology-Radiation Protection of Attiki, Greece, has noted that "the aerosol produced during impact and combustion of depleted uranium munitions can potentially contaminate wide areas around the impact sites or can be inhaled by civilians and military personnel". The use of DU in incendiary ammunition is controversial because of potential adverse health effects and its release into the environment. The U.S. Department of Defense claims that no human cancer of any type has been seen as a result of exposure to either natural or depleted uranium.
== Adverse effects == As with other SGLT2 inhibitors, canagliflozin is associated with increased incidence of urinary tract infections, fungal infections of the genital area, thirst, elevations in LDL cholesterol, increased urination and episodes of low blood pressure. Rarely, use of canagliflozin is associated with necrotizing fasciitis of the perineum, also called Fournier gangrene. There are concerns that it may also increase the risk of diabetic ketoacidosis. Possible cardiovascular problems are an ongoing issue with gliflozin drugs. The pre-specified endpoint for cardiovascular safety in the canagliflozin clinical development program was "Major Cardiovascular Events Plus", defined as the occurrence of cardiovascular death, non-fatal myocardial infarctions, non-fatal strokes, or unstable angina leading to hospitalization. This endpoint occurred in more people in the placebo group (20.5%) than in the canagliflozin treated group (18.9%). Nonetheless, a United States Food and Drug Administration (FDA) advisory committee expressed concern regarding the cardiovascular safety of canagliflozin. A greater number of cardiovascular events was observed during the first 30 days in study subjects who received canagliflozin (0.45%) compared those who received placebo (0.07%), suggesting an early period of increased cardiovascular risk. In addition, there was an increased risk of stroke in subjects who received canagliflozin. However, none of these effects were statistically significant. Additional cardiovascular safety data from another ongoing study are expected in 2015.
Fermentation is less efficient at using the energy from glucose: only 2 ATP are produced per glucose, compared to the 38 ATP per glucose nominally produced by aerobic respiration. Glycolytic ATP, however, is produced more quickly. For prokaryotes to continue a rapid growth rate when they are shifted from an aerobic environment to an anaerobic environment, they must increase the rate of the glycolytic reactions. For multicellular organisms, during short bursts of strenuous activity, muscle cells use fermentation to supplement the ATP production from the slower aerobic respiration, so fermentation may be used by a cell even before the oxygen levels are depleted, as is the case in sports that do not require athletes to pace themselves, such as sprinting.
The Swiss Air Force operated a few USAAF P-51s that had been impounded by Swiss authorities during World War II after the pilots were forced to land in neutral Switzerland. After the war, Switzerland also bought 130 P-51s for $4,000 each. They served until 1958. Soviet Union The Soviet Union received at least 10 early-model ex-RAF Mustang Mk Is and tested them, but found them to "under-perform" compared to contemporary USSR fighters, relegating them to training units. Later Lend-Lease deliveries of the P-51B/C and D series, along with other Mustangs abandoned in Russia after the famous "shuttle missions", were repaired and used by the Soviet Air Force, but not in front-line service. Uruguay The Uruguayan Air Force used 25 P-51D Mustangs from 1950 to 1960; some were subsequently sold to Bolivia.
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
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。