The short version of heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-06-30 and is reviewed periodically as new material appears.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
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.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
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.
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。
A large-scale study was conducted in Mexico. The study compared 793,487 adults vaccinated with different vaccines with 4,792,338 unvaccinated adults between 24 December 2020, and 27 September 2021.The results were as follows:
The 19th century Sinologist Samuel Wells Williams wrote that in China, the best soy sauce was "made by boiling beans soft, adding an equal quantity of wheat or barley, and leaving the mass to ferment; a portion of salt and three times as much water are afterwards put in, and the whole compound left for two or three months when the liquid is pressed and strained".
== Advantages == SMB provides lower production cost by requiring less column volume, less chromatographic separation media ("packing" or "stationary phase"), using less solvent and less energy, and requiring far less labor. At industrial scale an SMB chromatographic separator is operated continuously, requiring less resin and less solvent than batch chromatography. The continuous operation facilitates operation control and integration into production plants.
=== Saturation binding === Saturation binding measures the specific binding of a radioligand at varying concentrations while at equilibrium. Through this method, the number of receptors can be determined as well as affinity of the ligand to these receptors. Saturation binding experiments are often called "Scatchard experiments" as they can be graphed as a Scatchard plot.
A document that describes the rights of the study participants, and includes details about the study, such as its purpose, duration, required procedures, and key contacts. Risks and potential benefits are explained in the informed consent document. The participant then decides whether or not to sign the document. Informed consent is not a contract, and the participant may withdraw from the trial at any time. (NLM) Inspection
Sources: en.wikipedia.org
== Bioinformatics resources and tools == Databases and computational tools for mimotopes have been an important part of phage display study. Databases, programs and web servers have been widely used to exclude target-unrelated peptides, characterize small molecules-protein interactions and map protein-protein interactions. Users can use three dimensional structure of a protein and the peptides selected from phage display experiment to map conformational epitopes. Some of the fast and efficient computational methods are available online.
Parasitic infections include trichomoniasis, pediculosis pubis, and scabies. Trichomoniasis is transmitted by a parasitic protozoan and is the most common non-viral STI. Most cases are asymptomatic but may present symptoms of irritation and a discharge of unusual odor. Pediculosis pubis, commonly called crabs, is a disease caused by the crab louse an ectoparasite. When the pubic hair is infested, the irritation produced can be intense. Scabies, also known as the "seven year itch", is caused by another ectoparasite, the mite Sarcoptes scabiei, giving intense irritation.
Classic maple syrup urine disease Intermediate maple syrup urine disease Intermittent maple syrup urine disease Thiamine-responsive maple syrup urine disease E3-deficient maple syrup urine disease These types can be classified based on time of onset, severity of symptoms, and level of BCKAD complex enzyme activity. Generally, the majority of patients will be classified into one of these five categories but some patients affected by maple syrup urine disease do not fit the criteria for the listed sub-divisions and may be categorized into unclassified maple syrup urine disease.
Most venous diseases involve obstruction such as a thrombus or insufficiency of the valves, or both of these. Other conditions may be due to inflammation, or compression. Ageing is a major independent risk factor for venous disorders. The medical speciality involved with the diagnosis and treatment of venous disorders is known as phlebology (also venology), and the specialist concerned is a phlebologist. There are a number of vascular surgeries and endovascular surgeries carried out by vascular surgeons to treat many venous diseases.
Sources: en.wikipedia.org
=== October–December 2007: Participatory notes issue === 18,000, 9 October 2007- The SENSEX crossed the 18,000 mark for the first time on 9 October 2007, gaining 788 points, to close at 18,280. The journey from 17,000 to 18,000 took just 8 trading sessions, which is the third fastest 1000-point rise in the history of the SENSEX. 19,000, 15 October 2007- The SENSEX crossed the 19,000 mark for the first time on 15 October 2007, gaining 640 points, to close at 19,059. It took just 4 trading sessions for the SENSEX to move from 18,000 to 19,000. This is the fastest 1000-point rise ever for the index. In addition, the rise from 16,000 to 19,000 in 17 trading sessions sets a record for the fastest 3,000-point rally in the history of the SENSEX. On 16 October 2007, SEBI (Securities & Exchange Board of India) proposed curbs on participatory notes which accounted for roughly 50% of FII investment in 2007. SEBI was not happy with P-notes because it was not possible to know who owned the underlying securities, and hedge funds acting through P-notes might therefore cause volatility in the Indian markets. However the proposals of SEBI were not clear and this led to a knee-jerk crash when the markets opened on the following day (17 October 2007). Within a minute of opening trade, the SENSEX crashed by 1,744 points or about 9% of its value – the biggest intra-day fall in Indian stock markets in absolute terms until then. This led to the automatic suspension of trade for one hour. Finance Minister P.
Paracetamol, or acetaminophen, is an analgesic and antipyretic agent used to treat fever and mild to moderate pain. It is a widely available over-the-counter drug sold generically or under various brand names, including Tylenol and Panadol. Paracetamol relieves pain in acute mild migraine and episodic tension headaches. At a standard dose, paracetamol slightly reduces fever, though it is inferior to ibuprofen in that respect: the benefits of its use for fever are unclear, particularly in the context of fever of viral origins. Paracetamol is effective for pain after wisdom tooth extraction, but it is less effective than ibuprofen. The combination of paracetamol and ibuprofen provides greater analgesic efficacy than either drug alone. The pain relief paracetamol provides in osteoarthritis is small and clinically insignificant. Evidence supporting its use in low back pain, cancer pain, and neuropathic pain is insufficient. Paracetamol is the first-line treatment for pain and fever in pregnancy; no causal association with neurodevelopmental disorders has been established, while untreated pain and fever can harm the mother and fetus. At a recommended maximum daily dose for an adult of three to four grams, paracetamol is safe and effective in the short term when used as directed, with uncommon adverse effects similar to those of ibuprofen. It is often used in patients who cannot tolerate nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen.
The National Commission on Terrorist Attacks Upon the United States, popularly known as the 9/11 Commission, chaired by Thomas Kean, was formed in late 2002 to prepare a thorough account of the circumstances surrounding the attacks, including preparedness for and the immediate response to the attacks. The commission issued the 9/11 Commission Report in July 2004, a 585-page report based on its investigations. The report detailed the events leading up to the attacks, concluding that they were carried out by al-Qaeda. The commission also examined how security and intelligence agencies were inadequately coordinated to prevent the attacks. According to the report, "We believe the 9/11 attacks revealed four kinds of failures: in imagination, policy, capabilities, and management." The commission made numerous recommendations on how to prevent future attacks, and in 2011 was dismayed that several of its recommendations had yet to be implemented.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
Reversed-phase high-performance liquid chromatography is the standard method, with detection in the ultraviolet range. Peak area percentage yields a purity figure for the main component. Mass spectrometry is normally run alongside to confirm molecular identity.