The short version of ACTH fragment fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-12-13 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.
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 | 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 |
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.
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.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
The intersection of fields from the above pair of categories gives rise to fields such as bryogeography, the study of the distribution of mosses. Different parts of plants also give rise to their own subfields, including xylology, carpology (or fructology), and palynology, these being the study of wood, fruit and pollen/spores respectively. Botany also overlaps on the one hand with agriculture, horticulture and silviculture, and on the other hand with medicine and pharmacology, giving rise to fields such as agronomy, horticultural botany, phytopathology, and phytopharmacology.
Hird's lawyer, Steven Amendola, asserted that the AFL withdrew all charges against Hird under the deeds of settlement that he and the club signed with the AFL. At the time of the media report, Hird was considering legal action against both the AFL and Demetriou. Essendon chairman Paul Little said that Hird would be wanted as the senior coach once his suspension was served and that he had been offered a two-year extension from 2015, which would have seen him coaching until the end of the 2016 season. However, Hird resigned after round 20 in August 2015, near the end of the season, with the team near the bottom of the ladder.
=== Pain management === The circumcision procedure causes pain, and for neonates this pain may interfere with mother-infant interaction or cause other behavioral changes, so the use of analgesia is advocated and required by law in some countries. Ordinary procedural pain may be managed in pharmacological and non-pharmacological ways. Pharmacological methods, such as localized or regional pain-blocking injections and topical analgesic creams, are safe and effective. The ring block and dorsal penile nerve block (DPNB) are the most effective at reducing pain, and the ring block may be more effective than the DPNB. They are more effective than EMLA (eutectic mixture of local anesthetics) cream, which is more effective than a placebo. Topical creams have been found to irritate the skin of low birth weight infants, so penile nerve block techniques are recommended in this group. Circumcision is contraindicated for premature babies partially because of complications with anesthesia.
The first consignment of dressed beef left the Chicago stock yards in 1857 in ordinary boxcars retrofitted with bins filled with ice. Placing meat directly against ice resulted in discoloration and affected the taste, making it impractical. During the same period, Gustavus Swift experimented by moving cut meat using a string of ten boxcars with their doors removed, and made a few test shipments to New York during the winter months over the Grand Trunk Railway (GTR). The method proved too limited to be practical. Detroit's William Davis patented a refrigerator car that employed metal racks to suspend the carcasses above a frozen mixture of ice and salt. In 1868, he sold the design to George H. Hammond, a Detroit meatpacker, who built a set of cars to transport his products to Boston, using ice from the Great Lakes for cooling. The load tended to swing to one side when the car entered a curve at high speed, and use of the units was discontinued after several derailments. In 1878, Swift hired engineer Andrew Chase to design a ventilated, well-insulated car and positioned the ice in a compartment at the top of the car, allowing the chilled air to flow naturally downward. The meat was packed tightly at the bottom of the car to keep the center of gravity low and to prevent the cargo from shifting. Chase's design proved to be a practical solution, providing temperature-controlled carriage of dressed meats. This allowed Swift and Company to ship their products across the United States and internationally.
Sources: en.wikipedia.org
===== MeSH D08.811.277.151 – aminohydrolases ===== MeSH D08.811.277.151.300 – gtp cyclohydrolase MeSH D08.811.277.151.350 – guanine deaminase MeSH D08.811.277.151.418 – methenyltetrahydrofolate cyclohydrolase MeSH D08.811.277.151.486 – nucleoside deaminases MeSH D08.811.277.151.486.075 – adenosine deaminase MeSH D08.811.277.151.486.250 – cytidine deaminase MeSH D08.811.277.151.486.625 – cytosine deaminase MeSH D08.811.277.151.653 – nucleotide deaminases MeSH D08.811.277.151.653.060 – amp deaminase MeSH D08.811.277.151.653.200 – dcmp deaminase
Because of this fact, it has become common practice to establish the quality of NMR ensembles, by comparing it against the unique conformation determined by X-ray diffraction, for the same protein. However, the X-ray diffraction structure may not exist, and, since the proteins in solution are flexible molecules, a protein represented by a single structure may lead to underestimate the intrinsic variation of the atomic positions of a protein. A set of conformations, determined by NMR or X-ray crystallography may be a better representation of the experimental data of a protein than a unique conformation. The utility of a model will be given, at least in part, by the degree of accuracy and precision of the model. An accurate model with relatively poor precision could be useful to study the evolutionary relationships between the structures of a set of proteins, whereas the rational drug design requires both precise and accurate models. A model that is not accurate, regardless of the degree of precision with which it was obtained will not be very useful. Since protein structures are experimental models that can contain errors, it is very important to be able to detect these errors. The process aimed at the detection of errors is known as validation. There are several methods to validate structures, some are statistical like PROCHECK and WHAT IF while others are based on physical principles as CheShift, or a mixture of statistical and physics principles PSVS.
Susan M Gaines is an American writer. She is the author of the novels Accidentals (2020) and Carbon Dreams (2001), and co-author with Geoffrey Eglinton and Jurgen Rullkötter of the science book Echoes of Life: What Fossil Molecules Reveal about Earth History (2009). Her short stories have been nominated twice for the Pushcart Prize. She is a former fellow of the Hanse Institute for Advanced Study in Germany. In 2018, she was awarded a Suffrage Science Award for women in science and science writers who have inspired others.
Acrosin is a digestive enzyme that acts as a protease. In humans, acrosin is encoded by the ACR gene. Acrosin is released from the acrosome of spermatozoa as a consequence of the acrosome reaction. It aids in the penetration of the Zona Pellucida.
A simple substance is a substance formed from atoms of one chemical element. The simple substances of the more electronegative atoms tend to share electrons (form covalent bonds) with each other. They form either small molecules (like hydrogen or oxygen) or giant structures stretching indefinitely (like carbon or silicon). The noble gases simply stay as single atoms, as they already have a full shell. Substances composed of discrete molecules or single atoms are held together by weaker attractive forces between the molecules, such as the London dispersion force: as electrons move within the molecules, they create momentary imbalances of electrical charge, which induce similar imbalances on nearby molecules and create synchronized movements of electrons across many neighbouring molecules.
Sources: en.wikipedia.org
=== Disability === Emotional mental disorders are a leading cause of disabilities worldwide. Investigating the degree and severity of untreated emotional mental disorders throughout the world is a top priority of the World Mental Health (WMH) survey initiative, which was created in 1998 by the World Health Organization (WHO). "Neuropsychiatric disorders are the leading causes of disability worldwide, accounting for 37% of all healthy life years lost through disease. These disorders are most destructive to low and middle-income countries due to their inability to provide their citizens with proper aid. Despite modern treatment and rehabilitation for emotional mental health disorders, "even economically advantaged societies have competing priorities and budgetary constraints".
In August 2020, scientists described one way cells—in particular cells of a slime mold and mouse pancreatic cancer-derived cells—are able to navigate efficiently through a body and identify the best routes through complex mazes: generating gradients after breaking down diffused chemoattractants which enable them to sense upcoming maze junctions before reaching them, including around corners.
== Trade == South Korea spent around $129 million in 2017 to purchase 275,000 metric tons of foreign kimchi, more than 11 times the amount it exported, according to data released by the Korea Customs Service in 2017. South Korea consumes 1.85 million metric tons of kimchi annually, or 36.1 kg per person. It imports a significant fraction of that, mostly from China, and runs a $47.3 million kimchi trade deficit.
== Research == Protein A is often coupled to other molecules such as a fluorescent dye, enzymes, biotin, colloidal gold or radioactive iodine without affecting the antibody binding site. Examples including protein A–gold (PAG) stain is used in immunogold labelling, fluorophore coupled protein A for immunofluorescence, and DNA docking strand coupled protein A for DNA-PAINT imaging. It is also widely utilized coupled to magnetic, latex and agarose beads. Protein A is often immobilized onto a solid support and used as reliable method for purifying total IgG from crude protein mixtures such as serum or ascites fluid, or coupled with one of the above markers to detect the presence of antibodies. The first example of protein A being coupled to a porous bead for purification of IgG was published in 1972. Immunoprecipitation studies with protein A conjugated to beads are also commonly used to purify proteins or protein complexes indirectly through antibodies against the protein or protein complex of interest.
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.
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。