If you have been reading about counterion and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-07-17. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下,同时避免光照与反复升温。短期运输有时采用冷藏条件,但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数,以降低吸湿和微生物污染的风险。开封后若未一次用完,建议在干燥环境中密封并尽快放回低温储存。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
该化合物于二十世纪八十年代在俄罗斯被开发,相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性,而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示,这一方向促成了多个相关短肽的合成与筛选,而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上,包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升,但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验,人体对照研究数量有限。因此,该化合物的作用机制在文献中属于活跃讨论,而非已经确立的定论。
Semax 是一种人工合成的七肽,氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro,单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物,但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly,Semax 替换了中间两个残基,并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
Identity and purity are commonly assessed by reversed-phase high-performance liquid chromatography, with ultraviolet detection near 214 nanometers for the peptide backbone. Mass spectrometry, either electrospray or matrix-assisted laser desorption, confirms molecular mass and detects truncation or modification products. Amino acid analysis can verify composition. Because the sequence contains no strongly absorbing aromatic residue apart from phenylalanine, detection wavelengths are chosen carefully. Purity values above 95 percent are typical for research-grade material.
=== Artificial === As well as humans and other biological species, sentient artificial intelligences are also members of the Culture. These can be broadly categorised into drones and Minds. Also, by custom, as described in Excession, any artifact (be it a tool or vessel) above a certain capability level has to be given sentience.
== Contraindications == The glue must not get into blood vessels, as this could lead to clotting in the form of thromboembolism or disseminated intravascular coagulation, or to anaphylaxis (a severe allergic reaction).
==== NAADP does activate TPCs ==== The surprising conclusion in 2012 that TPCs are not involved in NAADP signalling was due to two technical difficulties that have since been overcome or explained. (i) The transgenic mice (designed to knockout both TPC1 and TPC2; double-knockout, DKO) retained sensitivity to NAADP. However, others have questioned whether these mice are true DKO when they are predicted to retain >90% of the TPC protein sequences (i.e. they express only mildly truncated TPCs which are still functional and NAADP-sensitive ). In a different DKO mouse that is demonstrably TPC-null, NAADP responses are completely abolished, confirming TPCs are an NAADP target. (ii) The authors could not observe NAADP-stimulated currents in patched lysosomes. These technically challenging protocols were overcome by others who have successfully observed NAADP-dependent lysosomal currents that are dependent on TPCs.
The Cossack Khmelnytsky Uprising of 1648–1657 engulfed the south-eastern regions of the Polish crown; its long-term effects were disastrous for the Commonwealth. The first liberum veto (a parliamentary device that allowed any member of the Sejm to dissolve a current session immediately) was exercised by a deputy in 1652. This practice would eventually weaken Poland's central government critically. In the Treaty of Pereyaslav (1654), the Ukrainian rebels declared themselves subjects of the Tsar of Russia. The Second Northern War raged through the core Polish lands in 1655–1660; it included a brutal and devastating invasion of Poland referred to as the Swedish Deluge. The war ended in 1660 with the Treaty of Oliva, which resulted in the loss of some of Poland's northern possessions. In 1657 the Treaty of Bromberg established the independence of the Duchy of Prussia. The Commonwealth forces did well in the Russo-Polish War (1654–1667), but the result was the permanent division of Ukraine between Poland and Russia, as agreed to in the Truce of Andrusovo (1667). Towards the end of the war, the Lubomirski's rebellion, a major magnate revolt against the king, destabilized and weakened the country. The large-scale slave raids of the Crimean Tatars also had highly deleterious effects on the Polish economy. Merkuriusz Polski, the first Polish newspaper, was published in 1661. In 1668, grief-stricken at the recent death of his wife and frustrated by the disastrous political setbacks of his reign, John II Casimir abdicated the throne and fled to France.[z]
The latest version of the tequila standard (NOM-006-SCFI-2012) updated the standard to specify that the silver class of tequila cannot contain additives, to allow the aging time for the ultra-aged class to be displayed on the label, and to prohibit the selling of bulk tequila through vending machines, and required registering the agave during the calendar year of its plantation and required annual updates. In 2018, the Mexican government approved a proposal to celebrate the third Saturday of March as National Tequila Day.
Sources: en.wikipedia.org
=== Patent protection and litigation === The original patent, U.S. patent 4,927,855, was granted to Laboratoire L. Lafon in 1990, covering the chemical compound of modafinil. This patent expired in 2010. In 1994, Cephalon filed a patent for modafinil in the form of particles of a defined size, represented by U.S. patent 5,618,845, which expired in 2015. Following the nearing expiration of marketing rights in 2002, generic manufacturers, including Mylan and Teva, applied for US Food and Drug Administration approval to market a generic form of modafinil, leading to legal challenges by Cephalon regarding the particle size patent. The patent RE 37,516 was declared invalid and unenforceable in 2011. In addition, Cephalon entered agreements with several generic drug manufacturers to delay the sale of generic modafinil in the US. These agreements were subject to legal scrutiny and antitrust investigations, culminating in a ruling by the Court of Appeals in 2016, which found that the settlements did not violate antitrust laws.
=== 28 February === The RSF launched a drone strike on the Merowe Power Station, leading to a power outage in the city. The JDF claimed to have intercepted an RSF supply shipment in North Darfur and "neutralized" foreign mercenaries, demanding apologies from Colombia. The claims were denied by the RSF.
The erythrocyte sedimentation rate (ESR or sed rate) is the rate at which red blood cells in anticoagulated whole blood descend in a standardized tube over a period of one hour. It is a common hematology test, and is a non-specific measure of inflammation. To perform the test, anticoagulated blood is traditionally placed in an upright tube, known as a Westergren tube, and the distance which the red blood cells fall is measured and reported in millimetres at the end of one hour. Since the introduction of automated analyzers into the clinical laboratory, the ESR test has been automatically performed. The ESR is influenced by the aggregation of red blood cells: blood plasma proteins, mainly fibrinogen, promote the formation of red cell clusters called rouleaux or larger structures (interconnected rouleaux, irregular clusters). As according to Stokes' law the sedimentation velocity varies like the square of the object's diameter, larger aggregates settle faster. While aggregation already takes place at normal physiological fibrinogen levels, these tend to increase when an inflammatory process is present, leading to increased ESR. The ESR is increased in inflammation, pregnancy, anemia, autoimmune disorders (such as rheumatoid arthritis and lupus), infections, some kidney diseases and some cancers (such as lymphoma and multiple myeloma). The ESR is decreased in polycythemia, hyperviscosity, sickle cell anemia, leukemia, chronic fatigue syndrome, low plasma protein (due to liver or kidney disease) and congestive heart failure.
==== Thiopeptides ==== Thiopeptide biosynthesis involves particularly extensive modification of the core peptide scaffold. Indeed, due to the highly complex structures of thiopeptides, it was commonly thought that these natural products were nonribosomal peptides. Recognition of the ribosomal origin of these molecules came in 2009 with the independent discovery of the gene clusters for several thiopeptides. The standard nomenclature for thiopeptide biosynthetic proteins follows that of the thiomuracin gene cluster. In addition to the precursor peptide, referred to as the A peptide, thiopeptide biosynthesis requires at least six genes. These include lanthipeptide-like dehydratases, designated the B and C proteins, which install dehydroalanine and dehydrobutyrine moieties by dehydrating Ser/Thr precursor residues. Azole and azoline synthesis is effected by the E protein, the dehydrogenase, and the G protein, the cyclodehydratase. The nitrogen-containing heterocycle is installed by the D protein cyclase via a putative [4+2] cycloaddition of dehydroalanine moieties to form the characteristic macrocycle. The F protein is responsible for binding of the leader peptide. Thiopeptide biosynthesis is biochemically similar to that of cyanobactins, lanthipeptides, and linear azol(in)e-containing peptides (LAPs). As with cyanobactins and LAPs, azole and azoline synthesis occurs via the action of an ATP-dependent YcaO-domain cyclodehydratase.
Sources: en.wikipedia.org
=== Pregnancy and breastfeeding === If needed in pregnancy, adequate human studies are lacking, therefore the drug should be given in pregnant women only if clearly indicated. It may cause hypotonia in the newborn if given closely before delivery.
=== Mechanism of action === At rest, serotonin is stored within the vesicles of presynaptic neurons. When stimulated by nerve impulses, serotonin is released as a neurotransmitter into the synapse, reversibly binding to the postsynaptic receptor to induce a nerve impulse on the postsynaptic neuron. Serotonin can also bind to auto-receptors on the presynaptic neuron to regulate the synthesis and release of serotonin. Normally serotonin is taken back into the presynaptic neuron to stop its action, then reused or broken down by monoamine oxidase.
While the main habitat of earthworms is in soil, they are not restricted to this habitat. The brandling worm Eisenia fetida lives in decaying plant matter and manure. Arctiostrotus vancouverensis from Vancouver Island and the Olympic Peninsula is generally found in decaying conifer logs. Aporrectodea limicola, Sparganophilus spp., and several others are found in mud in streams (riparian species). Some species are arboreal, some aquatic and some euryhaline (salt-water tolerant) and littoral (living on the sea-shore), e.g. Pontodrilus litoralis. Even in the soil species, special habitats, such as ultramafic soils derived from serpentine, have an earthworm fauna of their own, e.g. New Caledonian Acanthodrilidae. Vermicomposting of organic wastes is currently processed using the epigeic Eisenia fetida and Eisenia andrei which are particularly adapted to the consumption of fresh organic matter without deepening in the substrate (contrary to the anecis Lumbricus terrestris) and which tolerate the heat generated in compost heaps. Addition of this humified organic matter to the soil, preferably as a surface mulch, will improve moisture and nutrient availability, with beneficial effects on the soil microflora. It will also provide several species of earthworms with their food and nutrient requirements, and will create the optimum conditions of temperature and moisture that will stimulate their activity, although to a lesser extent than bacterial-mediated compost. Earthworms are environmental indicators of soil health.
The great chain of being (from Latin scala naturae 'ladder of being') is a hierarchical structure of all matter and life, thought by the medieval Islamic world and medieval Christianity to have been decreed by God. The chain begins with God and descends through angels, humans, animals and plants to minerals. The great chain of being is a concept derived from Plato, Aristotle (in his Historia Animalium), Plotinus and Proclus. Further developed during the Middle Ages, it reached full expression in early modern Neoplatonism.
===== Interferon production ===== Because of powerful interferon stimulating properties, before recombinant interferon alpha became available for medical use, SeV was selected, among other viruses, for the industrial large-scale IFN production. A procedure involving inactivated SeV treatment of human peripheral blood leukocytes from donors' blood was used for this production. Below is a table that listed known PRRs and interferon regulatory factors that are getting activated upon SeV infection.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
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。