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 2026-01-02. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
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.
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.
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。
==== PINK1, PARK7, PRKN ==== PINK1 (PARK6), PARK7 (DJ-1), and PRKN (PARK2, PARKIN) are all involved in mitochondrial activity. Mutations in these genes may cause mitochondrial dysfunction, an element of both idiopathic and familial PD. In addition, the PRKN gene encodes E3 ubiquitin ligase, which is involved in degradation of damaged proteins by ubiquitin. Many different PRKN-related mutations occur, leading to loss of protein or to protein-related loss of function. PRKN is the most common cause of autosomal-recessive PD, accounting for nearly 50% of typical early-onset parkinsonism. PRKN mutations account for 77% of juvenile PD cases. PINK1 encodes PTEN-induced putative kinase 1, and is the second-most common cause of autosomal-recessive PD. The PARK7 gene is located on chromosome 1p36 and encodes the DJ-1 protein. The DJ-1 protein is involved in cellular sensing of oxidative stress. DJ-1 related PD is rare, occurring in 0.4% - 1% of patients with early-onset PD.
=== Risk factor mitigation === Most patients with calciphylaxis are already on hemodialysis, or simply dialysis, but the length or frequency of sessions may be increased. The majority of dialysis patients are on a 4-hour three times per week schedule. Indications for increasing dialysis session length or frequency include electrolyte and mineral abnormalities, such as hyperphosphatemia, hypercalcemia, and hyperparathyroidism, all of which are also risk factors for development of calciphylaxis. Peritoneal dialysis patients should also transition to hemodialysis, as only hemodialysis carries the added benefit of better phosphate and calcium control. Surgical parathyroidectomy is also recommended for those who have difficulty managing phosphate and calcium level balance. However, risks include development of post-operative hungry bone syndrome (HBS), a disease state that causes low calcium and requires use of calcium supplementation and calcitriol, which should be avoided in patients with end-stage kidney disease and calciphylaxis.
Pre-preg is a composite material made from "pre-impregnated" fibers and a partially cured polymer matrix, such as epoxy or phenolic resin, or even thermoplastic mixed with liquid rubbers or resins. The fibers often take the form of a weave and the matrix is used to bond them together and to other components during manufacture. The thermoset matrix is only partially cured to allow easy handling; this B-Stage material requires cold storage to prevent complete curing. B-Stage pre-preg is always stored in cooled areas since heat accelerates complete polymerization. Hence, composite structures built of pre-pregs will mostly require an oven or autoclave to cure. The main idea behind a pre-preg material is the use of anisotropic mechanical properties along the fibers, while the polymer matrix provides filling properties, keeping the fibers in a single system.
==== Entrepreneurial ==== The entrepreneurial model looks at either the individual criminal or a smaller group of organized criminals, that capitalize off the more fluid 'group-association' of contemporary organized crime. This model conforms to social learning theory or differential association in that there are clear associations and interaction between criminals where knowledge may be shared, or values enforced, however, it is argued that rational choice is not represented in this. The choice to commit a certain act, or associate with other organized crime groups, may be seen as much more of an entrepreneurial decision – contributing to the continuation of a criminal enterprise, by maximizing those aspects that protect or support their own individual gain. In this context, the role of risk is also easily understandable, however it is debatable whether the underlying motivation should be seen as true entrepreneurship, or entrepreneurship as a product of some social disadvantage. The criminal organization, much in the same way as one would assess pleasure and pain, weighs such factors as legal, social and economic risk to determine potential profit and loss from certain criminal activities. This decision-making process rises from the entrepreneurial efforts of the group's members, their motivations and the environments in which they work.
Sources: en.wikipedia.org
In a flowing plasma afterglow, ions are formed in a flow of inert gas, typically helium or argon. Reagents are added downstream to create ion products and study reaction rates. Flowing-afterglow mass spectrometry is used for trace gas analysis for organic compounds.
=== Economics === Estimated costs for a 12-week treatment of elbasvir/grazoprevir are upwards of $54,600. Other treatments that work in a similar manner have effectively more costs. Some treatments for Hepatitis C are on the cheaper side, in some instances as low as $8,400. Additional ribavirin costs can add between $500 and $900. These cheaper prescriptions are however interferon-based treatments and do not target every genotype of the HCV. These regimens were the priority treatment before 2011. Two examples of these treatments are alfa-2a and alfa-2b costing $9250 and $8400, respectively.
== External links == Open source software for calculating SPINA-GBeta and other parameters for endotyping glucose homeostasis. (Permanent DOI), (General information and US mirror) Functions for R and S for calculating SPINA-GBeta, SPINA-GR and SPINA-DI. (Permanent DOI) Package "SPINA" for the statistical environment R
Alice in Chains were added as openers to Ozzy Osbourne's No More Tours tour. Days before the tour began, Staley broke his foot in an ATV accident, forcing him to use crutches on stage. During the tour, Starr was fired following the Hollywood Rock concert in Rio de Janeiro on January 22, 1993, and was replaced by former Ozzy Osbourne bassist Mike Inez. During June–August 1993, Alice in Chains joined Primus, Tool, Rage Against the Machine and Babes in Toyland for the alternative rock festival Lollapalooza, which was the last major tour the band played with Staley.
== Partners == Schrödinger's partners include pharmaceutical companies, including Bayer, Takeda, heavy industries, including Boeing, Sabic, and more. Nimbus Therapeutics, co-founded by Schrödinger, uses Schrödinger's drug screening and design platform for drug discovery. In 2016, Nimbus Therapeutics sold an Acetyl-CoA carboxylase (ACC) inhibitor designed by Schrödinger to Gilead Sciences in a deal worth up to $1.2 billion. As of spring 2019 the ACC inhibitor was moving through late-stage clinical trials in non-alcoholic steatohepatitis.
Sources: en.wikipedia.org
Evidence of infection in fossil remains is a subject of interest for paleopathologists, scientists who study occurrences of injuries and illness in extinct life forms. Signs of infection have been discovered in the bones of carnivorous dinosaurs. When present, however, these infections seem to tend to be confined to only small regions of the body. A skull attributed to the early carnivorous dinosaur Herrerasaurus ischigualastensis exhibits pit-like wounds surrounded by swollen and porous bone. The unusual texture of the bone around the wounds suggests they were affected by a short-lived, non-lethal infection. Scientists who studied the skull speculated that the bite marks were received in a fight with another Herrerasaurus. Other carnivorous dinosaurs with documented evidence of infection include Acrocanthosaurus, Allosaurus, Tyrannosaurus and a tyrannosaur from the Kirtland Formation. The infections from both tyrannosaurs were received by being bitten during a fight, like the Herrerasaurus specimen.
Iraq, which has this dynamic combination and much else besides, has not until recently been very much regarded as a power. But with the new discussions in OPEC, the ending of the Kurdistan war and the new round of fighting in Lebanon, its political voice is being heard more and more. The Baghdad regime is the first oil-producing government to opt for 100-per-cent nationalisation, a process completed with the acquisition of foreign assets in Basrah last December. It was the first to call for the use of oil as a political weapon against Israel and her backers. It gives strong economic and political support to the 'Rejection Front' Palestinians who oppose Arafat's conciliation and are currently trying to outface the Syrians in Beirut. He argued that the means through which the Baathist regime rose to power were similar to that of Iran: having crushed any political dissent and notions of an independent Kurdish state. He stated that the Ba'ath party "point to efforts made by the party press to stimulate criticism of revolutionary shortcomings" but that these "fall rather short of permitting any organised opposition". He claimed that Iraq defended this by claiming "that the country is surrounded by enemies and attacked by imperialist intrigue" but that this had led to the repression of Kurdish nationalists.
=== Megaloblastic anemia === Neutrophil hypersegmentation is one of the earliest, most sensitive and specific signs of megaloblastic anemia (mainly caused by hypovitaminosis of vitamin B12 & folic acid). Nuclear hypersegmentation of DNA in neutrophils strongly suggests megaloblastosis when associated with macro-ovalocytosis. If megaloblastosis is suspected, a formal lobe count/neutrophil (i.e. lobe index) above 3.5% can be obtained. Hypersegmentation persists for an average of 14 days after institution of specific therapy.
== History and chemistry == Diphenoxylate was first synthesized by Paul Janssen at Janssen Pharmaceutica in 1956 as part of a medicinal chemistry investigation of opioids. Diphenoxylate is made by combining a precursor of normethadone with norpethidine. Loperamide (Imodium) and bezitramide are analogs. Like loperamide, it has a methadone-like structure and a piperidine moiety.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受，但会加快降解风险。