Everything below concerns counterion. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized solid from research suppliers |
| Solubility | Freely soluble in water | Also dissolves in aqueous buffers; solutions are used fresh |
| Typical storage temperature | -20 °C for lyophilized powder | Short-term transport at 2-8 °C is common |
| Common analytical method | Reverse-phase HPLC | Paired with mass spectrometry for identity confirmation |
| Common synonyms | ACTH(4-10) analogue; MEHFPGP | N-terminal methionine retained in the chain |
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
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.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
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。
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。
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Administrative safeguards typically include security management process, security personnel, information access management, workforce training and management, and evaluation of security policies and procedures. Security management processes are one of the important administrative safeguards' examples. It is essential to reduce the risks and vulnerabilities of the system. The processes are mostly the standard operating procedures written out as training manuals. The purpose is to educate people on how to handle protected health information in proper behavior. Physical safeguards include lock and key, card swipe, positioning of screens, confidential envelopes, and shredding of paper copies. Lock and key are common examples of physical safeguards. They can limit physical access to facilities. Lock and key are simple, but they can prevent individuals from stealing medical records. Individuals must have an actual key to access to the lock. Lastly, technical safeguards include access control, audit controls, integrity controls, and transmission security. The access control mechanism is a common example of technical safeguards. It allows the access of authorized personnel. The technology includes authentication and authorization. Authentication is the proof of identity that handles confidential information like username and password, while authorization is the act of determining whether a particular user is allowed to access certain data and perform activities in a system like add and delete.
Drucker, Jens Holst and Svetlana Mojsov 2025: Member of the National Academy of Sciences (Section 42: Medical Physiology and Metabolism) 2025: Distinguished Medical Science Award by the National Library of Medicine - Joel Habener, Svetlana Mojsov and Lotte Bjerre Knudsen 2025: Carothers Award from the American Chemical Society Delaware Section 2025: Helen Dean King Award of Wistar Institute in Philadelphia 2026: Member of the Macedonian Academy of Sciences and Arts 2026: Kimberly Prize in Biochemistry and Molecular Genetics 2026: Boulder Peptide Foundation Meinehofer Award 2026: King Faisal Prize in Medicine 2026: Broermann Medical Innovation Award - Matthias Tschöp, Svetlana Mojsov and Richard DiMarchi 2027: Elaine Redding Brinster Prize in Science or Medicine - Svetlana Mojsov and Lotte Bjerre Knudsen
== See also == List of antidepressants Noradrenergic and specific serotonergic antidepressant (NaSSA) Serotonin releasing agent (SRA) Serotonin–norepinephrine reuptake inhibitor (SNRI) Serotonin–norepinephrine–dopamine reuptake inhibitor (SNDRI)
Sources: en.wikipedia.org
The city of Le Havre has some of the oldest sports clubs in France: the Le Havre Rowing Society (1838), the Regatta Society of Le Havre (1838), and Le Havre Athletic Club (1872), doyen of French football and rugby clubs. The city also hosted the sailing events for the 1900 and 1924 Summer Olympics, respectively. Le Havre is dominated by three professional sports teams: the first is the Le Havre AC football team who were relegated from Ligue 1 after the 2008–2009 season but gained promotion back to Ligue 1 in 2023. Its training centre is well-reputed for having trained a number of international French players, including Vikash Dhorasoo, Julien Faubert, Jean-Alain Boumsong, Lassana Diarra, and Steve Mandanda. The second major sports team is Saint Thomas Basketball who represent the city in LNB Pro A. Thirdly the HAC women's team who play in the first division with many international players in its ranks. The team won their first major national title, the Coupe de France for women's handball in 2006. Le Havre Rugby athletic club plays in Fédérale 3 (equivalent to fifth division). The Hockey Club of Le Havre played at the fourth level nationally (Division 3) for the 2008–2009 season. The team is nicknamed the "Dock's du Havre". The maritime side of the city is found in many sports: for example, the tradition of sailing is old. On 29 July 1840 the first French pleasure boat regatta was held. Today, Le Havre is known as a water sports and Seaside resort. The marina can host deepwater vessels around the clock in any weather.
The most recognizable and most common form of dwarfism in humans is achondroplasia, which accounts for 70% of dwarfism cases, and occurs in 4 to 15 out of 100,000 live births. It produces rhizomelic short limbs, increased spinal curvature, and distortion of skull growth. In achondroplasia the body's limbs are proportionately shorter than the trunk (abdominal area), with a larger head than average and characteristic facial features. Achondroplasia is an autosomal dominant disorder caused by the presence of an altered allele in the genome. If a pair of achondroplasia alleles are present, the result is fatal, usually perinatally. Achondroplasia is a mutation in the fibroblast growth factor receptor 3. In the context of achondroplasia, this mutation causes FGFR3 to become constitutively active, inhibiting bone growth.
=== Agriculture and decontamination === During the growth, microalgae produce and secrete metabolites such as acetate or glycerol into the medium. Extracellular metabolites (EM) from microalgae have important ecological significances. For instance, marine microalgae release a large amount of dissolved organic substances (DOS), which serve as energy sources for heterotrophs in algal-bacterial symbiotic interactions. Excretions into the pericellular space determine, to a great degree, the course of allelopathic interactions between microalgae and other microorganisms. Some allelopathic compounds from microalgae are realized as environment-friendly herbicides or biocontrol agents with direct perspectives for their biotechnological use. In B. subtilis, the protein matrix component, TasA, and the exopolysaccharide have both been shown to be essential for effective plant-root colonization in Arabidopsis and tomato plants. It was also suggested that TasA plays an important role in mediating interspecies aggregation with streptococci. Due to the growing need to find a more efficient and environmentally friendly alternative to conventional waste removal methods, industries are paying more attention to the function of bacteria and their EPS sugars in bioremediation. Researchers found that adding EPS sugars from cyanobacteria to wastewaters removes heavy metals such as copper, cadmium and lead. EPS sugars alone can physically interact with these heavy metals and take them in through biosorption.
Entire genomes of lichen-forming fungi can be sequenced, offering a wealth of characters for phylogenetic analysis and revealing genes involved in symbiosis. These advances have led to a surge of new insights—for instance, the discovery of many previously unrecognized species within what were thought to be single, widespread taxa. Yet, traditional morphology and chemistry remain indispensable in the field. A 2018–2020 survey found that fewer than half of newly described lichen species were accompanied by any DNA data, and only about 10% had more than three genetic loci sequenced. Most new species are still identified and circumscribed using features like spores, reproductive structures, and secondary metabolites. Lichenologists thus operate with a blend of old and new methods: high-throughput sequencing might pinpoint lineages of interest, but microscopy, spot tests, and thin-layer chromatography are still routinely used to characterize and confirm the organisms. The field is moving toward an integrative approach in which morphological, chemical, and molecular evidence are all brought to bear on defining species and higher taxa.
Sources: en.wikipedia.org
According to the procedure described in the 1975 Aron patent, and the Pharmaceutical Manufacturing Encyclopedia, equimolar amounts of dimethylamine and 2-cyanoguanidine are dissolved in cold toluene to make a concentrated solution, and an equimolar amount of hydrogen chloride is slowly added. The mixture begins to boil, and after cooling, metformin hydrochloride precipitates with a 96% yield. Excess addition of hydrogen chloride results in the formation of the more soluble metformin dichloride salt, a recently reported impurity.
== External links == "Do insects have blood?". Boston Globe. October 17, 2005. Archived from the original on October 2, 2022. Bolstad, Kat (May 2, 2008). "Blue Squid Blood - Murky Water". Te Papa Tongarewa Museum of New Zealand. Archived from the original on April 2, 2015.
This is an example of the Nernst equation. The potential is known as a reduction potential. Standard electrode potentials are available in a table of values. Using these values, the actual electrode potential for a redox couple can be calculated as a function of the ratio of concentrations. The equilibrium potential for a general redox half-reaction (See #Equilibrium constant above for an explanation of the symbols)
Sources: en.wikipedia.org
It consists mainly of animal experiments and small clinical reports, with much of the clinical material published in Russian-language journals. Large independent trials are scarce. Separating reliable effects from chance findings is consequently difficult.
A fraction of an intranasal dose is thought to reach the central nervous system, and this route is favoured partly for that reason. The proportion is not well characterized. Direct measurement in humans remains difficult with current methods.
Raised BDNF and NGF expression has been reported across several animal studies, which makes the signal fairly consistent. Whether the same change occurs in humans at usable doses is not established. It is best treated as a working hypothesis rather than a confirmed clinical mechanism.
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.