This is a working overview of N-acetyl Semax, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-10-08 and is reviewed periodically as new material appears.
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.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
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.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
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.
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
Calcitriol is a hormone and the active form of vitamin D3, normally made in the kidney. It is also known as or 1,25-dihydroxycholecalciferol (1,25-(OH)2D3). It binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the expression of many genes. Calcitriol increases blood calcium mainly by increasing the uptake of calcium from the intestines. Calcitriol can be given as a medication for the treatment of osteoporosis, osteomalacia, familial hypophosphatemia, low blood calcium due to hypoparathyroidism, and low blood calcium and hyperparathyroidism due to kidney disease. It can be taken by mouth or by injection into a vein. Excessive amounts or intake can result in weakness, headache, nausea, constipation, urinary tract infections, and abdominal pain. Serious side effects may include high blood calcium and anaphylaxis. Calcitriol was identified as the active form of vitamin D3 in 1971 and the drug was approved for medical use in the United States in 1978. It is available as a generic medication. In 2023, it was the 249th most commonly prescribed medication in the United States, with more than 1 million prescriptions. It is on the World Health Organization's List of Essential Medicines.
==== Fibers ==== The tubers of the mashua are a good source of dietary fiber. Mashua tubers contain approximately 5 to 7 g of fiber per 100 g of dry matter, depending on factors like growing conditions and the variety of mashua species. Dietary fiber content is supposed to have beneficial health effects and help relieve functional constipation, a common gastrointestinal problem in children.
traffic in refrigerated fruit hit 600,000 short tons (544,311 t; 535,714 long tons). 1908: Japan's first refrigerator cars entered service. The cars were used for seafood transport, as with most other Japanese reefers. 1913: The number of thermally insulated railcars (most of which were cooled by ice) in the U.S. topped 100,000. 1920: The Fruit Growers Express (or FGE, a former subsidiary of the Armour Refrigerator Line) was formed using 4,280 reefers acquired from Armour & Co. 1923: FGE and the Great Northern Railway form the Western Fruit Express (WFE) to compete with the Pacific Fruit Express and Santa Fe Refrigerator Despatch in the West. 1925 to 1930: Mechanically refrigerated trucks enter service and gain public acceptance, particularly for the delivery of milk and ice cream. 1926: The FGE expanded its service into the Pacific Northwest and the Midwest through the WFE and the Burlington Refrigerator Express Company (BREX), its other partly owned subsidiary. FGE purchased 2,676 reefers from the Pennsylvania Railroad. 1928: The FGE formed the National Car Company as a subsidiary to service the meat transportation market. Customers include Kahns, Oscar Mayer, and Rath. 1930: The number of refrigerator cars in the United States reached its maximum of approximately 183,000. 1931: The SFRD reconfigured seven reefers to use dry ice as a cooling agent. 1932: Japanese Government Railways built vehicles specially made for dry ice coolant. 1934: The Interstate Commerce Commission (ICC) regulation #201 came into effect, banning billboard advertisements on freight cars.
== Control of the oxygen reduction potential == Spoilage bacteria and lipid oxidation usually need oxygen, so reducing the oxygen around fish can increase shelf life. This is done by controlling or modifying the atmosphere around the fish, or by vacuum packaging. Controlled or modified atmospheres have specific combinations of oxygen, carbon dioxide and nitrogen, and the method is often combined with refrigeration for more effective fish preservation.
Sources: en.wikipedia.org
The history of penicillin traces how observations of antibiotic activity in the mould Penicillium led to the development of penicillins, a family of widely used antibiotics. Ancient societies used moulds to treat infections, and many people observed the inhibition of bacterial growth by moulds. While working at St Mary's Hospital in London in 1928, Scottish physician Alexander Fleming was the first to show experimentally that a Penicillium mould secretes an antibacterial substance, which he named "penicillin". The mould was found to be a variant of Penicillium chrysogenum (now called Penicillium rubens), a contaminant of a bacterial culture in his laboratory. The work on penicillin at St Mary's ended in 1929. In 1939, a team of scientists at the Sir William Dunn School of Pathology at the University of Oxford, led by Howard Florey, which included Edward Abraham, Ernst Chain, Mary Ethel Florey, Norman Heatley and Margaret Jennings, began researching penicillin. They developed a method for cultivating the mould and extracting, purifying and storing penicillin from it, together with an assay for measuring its purity. "Penicillin" now became the name of the active ingredient in the mould juice. They carried out experiments on animals to determine penicillin's safety and effectiveness before conducting clinical trials and field tests. They derived penicillin's chemical formula and determined how it works. The private sector and the United States Department of Agriculture located and produced new strains and developed mass production techniques.
== Co-Workers == Klaus Mosbach supervised more than sixty Ph.D.’s over the years. A number of highly recognized scientists emerged from this pool, including the following professors C. Borrebaeck (in part), B.Sellergren (who is now a professor in Germany). P. Brodelius, Leif Bulow, B. Danielsson, B. Hahn-Hägerdahl (in part), A.C. Koch. Schmidt, P.O. Larsson, C. F. Mandenius, B. Mattiasson, M.O. Månsson, I.A. Nicholls (starting as post doc), R. Ohlsson (in part), Lei Ye and S. Olsson working all in Sweden. To this a number of Professors working in other countries outside Sweden including, L.Fischer, K. Haupt, C.Lowe, H.Zhang, Deepak Chandrasekaran. Mosbach collaborated with numerous companies over the years, including Biogen and later Hybritech, Eli Lilly, Igen, Hofman la Roche and was involved in the formation of start-up companies by himself likewise former students of him have been successful in starting up companies like B.Ekberg, N.Siegbahn, Kurt Nilsson, Kjell Nilsson, Dariao Kriz.
Monitoring members' progress in implementing anti–money laundering measures, Reviewing and reporting on laundering trends, techniques, and countermeasures, and Promoting the adoption and implementation of FATF anti–money laundering standards globally. The FATF currently comprises 34 member jurisdictions and 2 regional organisations, representing most major financial centres in all parts of the globe. The United Nations Office on Drugs and Crime maintains the International Money Laundering Information Network, a website that provides information and software for anti–money laundering data collection and analysis. The World Bank has a website that provides policy advice and best practices to governments and the private sector on anti–money laundering issues. The Basel AML Index is an independent annual ranking that assesses the risk of money laundering and terrorist financing around the world.
Salidroside (rhodioloside) is a glucoside of tyrosol found in the plant Rhodiola rosea. It has been studied, along with rosavin, as one of the potential compounds responsible for the putative antidepressant and anxiolytic actions of this plant. Salidroside may be more active than rosavin, even though many commercially marketed Rhodiola rosea extracts are standardized for rosavin content rather than salidroside.
cytosol Also hyaloplasm and groundplasm. The soluble aqueous phase of the cytoplasm, in which small particles such as ribosomes, proteins, nucleic acids, and many other molecules are suspended or dissolved, excluding larger structures and organelles such as mitochondria, chloroplasts, lysosomes, and the endoplasmic reticulum.
Sources: en.wikipedia.org
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.