Semax is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-04-02. 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。
==== Personality ==== Almost all Culture citizens are very sociable and of great intellectual capability and learning, and possess very well‑balanced psyches. Their biological make-up and their growing up in an enlightened society make neuroses and lesser emotions like greed or (strong) jealousy practically unknown, and produce persons that, in any lesser society, appear very self-composed and charismatic. Character traits like strong shyness, while very rare, are not fully unknown, as shown in Excession. As described there and in Player of Games, a Culture citizen who becomes dysfunctional enough to pose a serious nuisance or threat to others would be offered (voluntary) psychological adjustment therapy and might potentially find themself under constant (non-voluntary) oversight by representatives of the local Mind. In extreme cases, as described in Use of Weapons and Surface Detail, dangerous individuals have been known to be assigned a "slap-drone", a robotic follower who ensures that the person in question doesn't continue to endanger the safety of others.
Since 1997, the US federal government has prohibited the harvesting of white sharks in US waters, requiring that any incidentally caught shark be released immediately. Management of the species is split by region: the 2006 Consolidated Atlantic Highly Migratory Species Fishery Management Plan covers the Atlantic, while the Pacific Fishery Management Council oversees the Pacific. The white shark also receives protection in National Marine Sanctuaries managed by the National Oceanic and Atmospheric Administration. Some states provide additional safeguards. California has protected the species within its waters (up to 3 miles (4.8 km) offshore) since 1994 and in 2013, added white sharks to the California Endangered Species Act, which introduced strict permit requirements for both scientific research and incidental bycatch. In 2019, the state further banned the use of bait, chum, or decoys to lure white sharks in state waters and prohibited their use within one nautical mile of any shoreline or pier when a shark is present. A 2014 study estimated the white shark population along the California coastline to be approximately 2,400 individuals. Massachusetts also provides state-level protection, having prohibited the capture of white sharks in 2005 and banning the use of chum or bait to lure them in 2015. In 2025, authorities restricted shore-based fishing around Cape Cod in response to viral videos of anglers catching white sharks.
== Divisions == The chain of being hierarchy consists of God at the top, above angels, which like him are entirely spirit, without material bodies, and hence unchangeable. Beneath them are humans, consisting both of spirit and matter; they change and die, and are thus essentially impermanent. Lower are animals and plants. At the bottom are the mineral materials of the earth itself; they consist only of matter. Thus, the higher the being is in the chain, the more attributes it has, including all the attributes of the beings below it. The minerals are, in the medieval mind, a possible exception to the immutability of the material beings in the chain, as alchemy promised to turn lower elements like lead into those higher up the chain, like silver or gold.
== Benefits == One of the main advantages of this method of preparing frozen food is that the freezing process takes only a few minutes. The exact time depends on the type of IQF freezer and the product. The short freezing prevents formation of large ice crystals in the product's cells, which destroys the membrane structures at the molecular level. This makes the product keep its shape, colour, smell and taste after defrost, to a far greater extent. Another advantage of IQF technology is its ability to separate units of the products during freezing, which produces a higher quality product compared to block freezing. This is important for food sustainability, as the consumer can defrost and use the exact quantity needed. A growing demand in IQF products is registered at global level due to the higher quality of these products and to the benefit of having separately frozen pieces. IQF is also a common pre-treatment for freeze-drying food because both processes preserve the size, taste and cell structure of the food better than methods such as traditional block freezing or air drying.
Sources: en.wikipedia.org
Natural GnRH was previously prescribed as gonadorelin hydrochloride (Factrel) and gonadorelin diacetate tetrahydrate (Cystorelin) for use in treating human and dairy cattle diseases respectively. Modifications of the decapeptide structure of GnRH to increase half life have led to GnRH1 analog medications that either stimulate (GnRH1 agonists) or suppress (GnRH antagonists) the gonadotropins. These synthetic analogs have replaced the natural hormone in clinical use. Its analogue leuprorelin is used for continuous infusion, to treat breast cancer, endometriosis, prostate cancer, and following research in the 1980s by researchers, including Dr. Florence Comite of Yale University, it was used to treat precocious puberty. The expression of GnRH receptors in cancers has led to the use of GnRH as a targeting molecule to deliver toxins specifically to the receptor-expressing cancer cells. In a similar concept, its use to deliver toxins to pituitary gonadotropes in animals has been explored as a means of sterilization, with limited success. GnRH was also shown to successfully deliver DNA into the pituitary gonadotropes where the expressed protein blocked expression of the hormones that regulate reproduction. A Cochrane Review is available which investigates whether GnRH analogues, given before or alongside chemotherapy, could prevent damage to women's ovaries caused by chemotherapy. GnRH agonists appear to be effective in protecting the ovaries during chemotherapy, in terms of menstruation recovery or maintenance, premature ovarian failure and ovulation.
Agouti signalling peptide adopts an inhibitor cystine knot motif. Along with the homologous Agouti-related peptide, these are the only known mammalian proteins to adopt this fold. The peptide consists of 131 amino acids.
== DHIS2 software == As a digital solution for data collection and management, DHIS2 can be used for aggregate data (e.g. routine health facility data, staffing, equipment, infrastructure, population estimates, etc.), event data (e.g. disease outbreaks, survey/audit data, patient satisfaction surveys, etc.), and individual-level longitudinal data (e.g. vaccination records, lab sample collection and testing, patient treatment and follow-up, student progress, etc.). The system supports the capture of data linked to any level in an organizational hierarchy at any data collection frequency. DHIS2 includes built-in tools for analytics, including dashboards, charts, pivot tables and maps, as well as data validation and data quality features. It also includes tools to support collaborative data use, such as sharing, commenting and interpretation. The DHIS2 platform can be extended with custom applications (which can be published and shared through the DHIS2 App Hub) or integrated with third-party software or external data sources through the open web API. DHIS2 supports health data standards such as FHIR, SNOMED GPS, LOINC, and ICD-11, as well as the generic ADX format for aggregate data exchange. The DHIS2 data model and platform are generic by design, not specifically tailored to the health context, to facilitate the application of DHIS2 to a variety of use cases. DHIS2 is a web-based platform. The core software and database are hosted on a server, which can be either physically located in the country of ownership or cloud-based.
Heat or ionizing irradiation can be used to kill the bacteria that cause decomposition. Heat is applied by cooking, blanching or microwave heating in a manner that pasteurizes or sterilizes fish products. Cooking or pasteurizing does not completely inactivate microorganisms and may need to be followed with refrigeration to preserve fish products and increase their shelf life. Sterilised products are stable at ambient temperatures up to 40 °C, but to ensure they remain sterilized they need packaging in metal cans or retortable pouches before the heat treatment.
Paper-based microfluidics are microfluidic devices that consist of a series of hydrophilic cellulose or nitrocellulose fibers that transport fluid from an inlet through the porous medium to a desired outlet or region of the device, by means of capillary action. This technology builds on the conventional lateral flow test which is capable of detecting many infectious agents and chemical contaminants. The main advantage of this is that it is largely a passively controlled device unlike more complex microfluidic devices. Development of paper-based microfluidic devices began in the early 21st century to meet a need for inexpensive and portable medical diagnostic systems.
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。