The short version of neuropeptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity | 95% or higher | By reversed-phase HPLC area |
| Identity method | Electrospray mass spectrometry | Confirms molecular mass |
| Purity method | Reversed-phase HPLC | Detection near 214 nm |
| Primary degradation | Methionine oxidation | Sulfoxide product, +16 Da |
| Solution storage | 2-8 °C, short term | Aliquot to avoid freeze-thaw |
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.
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.
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.
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.
He then moved on to Brazil in their fight for independence from Portugal. At their peak by 1819 around 10,000 men from the British Isles served in South America to fight against the Spanish. British diplomacy also played a key role; in particular the role of foreign secretaries Viscount Castlereagh and later George Canning both of whom wanted to see the demise of Spain's South American colonies. Castlereagh's greatest achievement was to settle a deal with the European powers at the Congress of Aix-La-Chapelle in 1818 and the Congress of Verona four years later. This blocked aid to Spain which inhibited her reconquest of South America. With the Royal Navy in command of the oceans this set the precedence - they were also a decisive factor in the struggle for independence of certain Hispanic American countries.
=== Pharmacokinetics === The oral bioavailability of acetylcysteine is relatively low due to extensive first-pass metabolism in the gut wall and liver. It ranges between 6% and 10%. Intravenous administration of acetylcysteine bypasses the first-pass metabolism, resulting in higher bioavailability compared to oral administration. Intravenous administration of acetylcysteine ensures nearly 100% bioavailability as it directly enters the bloodstream. Acetylcysteine is extensively liver metabolized, CYP450 minimal. After a single IV administration, urine excretion is 30% at 0.11 L/hr/kg, with a half-life of 5.6 hours. Acetylcysteine is the N-acetyl derivative of the amino acid L-cysteine and is a precursor in the formation of the antioxidant glutathione in the body. The thiol (sulfhydryl) group confers antioxidant effects and is able to reduce free radicals.
proved the intracellular uptake of cargo via endocytosis, along with cargo release as a result of coiled-coil dissociation. Dr. Ondřej Vaněk and colleagues utilized the same E3/K3-PHPMA system to attach an antibody to the polymer backbone to target the delivery of the drug system, which was successful in vitro. Coiled-coil polymer hybrid drug delivery systems can also be used in drug-free macromolecular therapeutic (DFMT) applications, whereby a coiled-coil-based system would be used to induce apoptosis in target cells. Specifically, Dr. Jindřich Kopeček and colleagues attempted to induce apoptosis in CD20-positive non-Hodgkin's lymphoma B-cells by mimicking the induction of apoptosis typically caused by the recognition of secondary antibodies to the CD20 antigen. In this case, apoptosis was induced upon the oligomerization of a PHMPA copolymer-conjugated coil to the anti-CD20 FAB fragment-conjugated coil (which would recognize and bind CD20). The coiled-coil motifs used in this system were the anti-parallel heterodimeric CCE/CCK coiled coils, which consist of pentaheptad repeats. This system was found to be successful at inducing apoptosis in those cells in vitro, providing an alternative to the anti-CD20 antibody drug Rituximab. Further studies have shown the efficacy of this system in vivo whereby malignant B-cells implanted in the bone marrow of mice were eradicated completely.
Static secondary-ion mass spectrometry, or static SIMS, is a secondary-ion mass spectrometry technique for chemical analysis including elemental composition and chemical structure of the uppermost atomic or molecular layer of a solid, which may be a metal, semiconductor, or plastic, with insignificant disturbance to its composition and structure. It is one of the two principal modes of operation of SIMS, which is the mass spectrometry of ionized particles emitted by a solid (or sometimes liquid) surface upon bombardment by energetic primary particles.
== Business and economics == Chain (real estate), a group of buyers/sellers that are linked together Chain of command, the line of authority and responsibility along which orders are passed Chain store, a retail shop outlets which share a brand and central management Chained dollars, used to express real dollar amounts adjusted over time for inflation Cinema chain, or movie chain Cold chain, a temperature-controlled supply chain Fast food chain Hotel chain Restaurant chain Supply chain, a coordinated system of organizations, people, activities, information and resources involved in moving a product or service from supplier to customer Value chain, a management concept first described by Michael Porter
Sources: en.wikipedia.org
February 14, 2013: European Union The recession in the Eurozone economy deepens with a fall of 0.6% in GDP in the fourth quarter of 2012. Of the major economies, Germany shrinks by 0.6%, France by 0.3% and Italy by 0.9%. The economy of the 27 members of the EU, including non-Eurozone members such as Denmark and the UK, shrinks by 0.5%.
Urbach–Wiethe disease is a very rare recessive genetic disorder, with approximately 400 reported cases since its discovery. It was first officially reported in 1929 by Erich Urbach and Camillo Wiethe, although cases may be recognized dating back as early as 1908. The symptoms of the disease vary greatly from individual to individual. They may include a hoarse voice, lesions and scarring on the skin, easily damaged skin with poor wound healing, dry, wrinkly skin, and beading of the papules around the eyelids. All of these are results of a general thickening of the skin and mucous membranes. In some cases there is also a hardening of brain tissue in the medial temporal lobes, which can lead to epilepsy and neuropsychiatric abnormalities. The disease is typically not life-threatening and patients do not show a decreased life span. Because Urbach–Wiethe disease is an autosomal recessive condition, individuals can be carriers of the disease but show no symptoms. The disease is caused by loss-of-function mutations to chromosome 1 at 1q21, the extracellular matrix protein 1 (ECM1) gene. The dermatological symptoms are caused by a buildup of a hyaline material in the dermis and the thickening of the basement membranes in the skin. Urbach–Wiethe disease is typically diagnosed by its clinical dermatological manifestations, particularly the beaded papules on the eyelids. The discovery of the mutations within the ECM1 gene has allowed the use of genetic testing to confirm an initial clinical diagnosis.
ALDHs function in cell differentiation, proliferation, oxidation, and drug resistance. These enzymes are only one example of the many different types of dehydrogenases in the human body; their wide array of functions, and the impact that their deactivation or mutations has upon crucial cell processes underscores the importance of all dehydrogenases in maintaining body homeostasis.
Cytolysis occurs when a cell bursts due to an osmotic imbalance that has caused excess water to move into the cell. Cytolysis can be prevented by several different mechanisms, including the contractile vacuole that exists in some paramecia, which rapidly pump water out of the cell. Cytolysis does not occur under normal conditions in plant cells because plant cells have a strong cell wall that contains the osmotic pressure, or turgor pressure, that would otherwise cause cytolysis to occur.
Several different types of fluorescent probes, like cyanine dyes, methyl violegen, or semiconductor quantum dots can be conjugated to silica nanoparticles and delivered into specific cells or injected in vivo. Carrier molecule RGD peptide has been very useful of targeted in vivo imaging. Topically applied surface-enhanced resonance Raman ratiometric spectroscopy (TAS3RS)- TAS3RS is another technique that is starting to make advancement in the medical field. It is an imaging technique that uses Folate Receptors (FR) to detect tumor lesions as small as 370 micrometers. Folate Receptors are membrane bound surface proteins that bind folates and folate conjugates with high affinity. FR is frequently overexpressed in a number of human malignancies including cancer of the ovary, lung, kidney, breast, bladder, brain, and endometrium. Raman imaging is a type of spectroscopy that is used in chemistry to provide structural fingerprint by which molecules can be identified. It relies upon inelastic scattering of photons, which result in ultra high sensitivity. There was a study that was done where two different surface enhanced resonance Raman scattering were synthesized (SERRS).
Sources: en.wikipedia.org
Since 1988, the library has administered the National Film Preservation Board. Established by congressional mandate, it selects twenty-five American films annually for preservation and inclusion in the National Film Registry, a collection of American films, for which the Library of Congress accepts nominations each year. There also exists a National Recording Registry administered by the National Recording Preservation Board that serves a similar purpose for music and sound recordings. The library has made some of these available on the Internet for free streaming and additionally has provided brief essays on the films that have been added to the registry. By 2015, the librarian had named 650 films to the registry. The films in the collection date from the earliest period to ones produced more than ten years ago; they are selected from nominations submitted to the board. Further programs included:
A comparative genomic study (in 2020) analyzed 494 complete genomes from the Pseudomonas genus, of which 189 were P. aeruginosa strains. The study observed that their protein count and GC content ranged between 5500 and 7352 (average: 6192) and between 65.6 and 66.9% (average: 66.1%), respectively. This comparative analysis further identified 1811 aeruginosa-core proteins, which accounts for more than 30% of the proteome. The higher percentage of aeruginosa-core proteins in this latter analysis could partly be attributed to the use of complete genomes. Although P. aeruginosa is a very well-defined monophyletic species, phylogenomically and in terms of ANIm values, it is surprisingly diverse in terms of protein content, thus revealing a very dynamic accessory proteome, in accordance with several analyses. It appears that, on average, industrial strains have the largest genomes, followed by environmental strains, and then clinical isolates. The same comparative study (494 Pseudomonas strains, of which 189 are P. aeruginosa) identified that 41 of the 1811 P. aeruginosa core proteins were present only in this species and not in any other member of the genus, with 26 (of the 41) being annotated as hypothetical. Furthermore, another 19 orthologous protein groups are present in at least 188/189 P. aeruginosa strains and absent in all the other strains of the genus.
== In popular culture == In the movie The Bucket List, billionaire health care magnate Edward Cole (played by Jack Nicholson) brings kopi luwak with him on all of his travels but is unaware of how the drink is produced. Carter Chambers (Morgan Freeman) explains how civets defecate kopi luwak coffee beans, and that the gastric juices of the defecated beans give kopi luwak its unique aroma. The Japanese manga series Beastars features an anthropomorphic civet character named Deshico that produces kopi luwak.
=== 2000s === Stanton was drafted by Essendon with the thirteenth overall selection in the 2003 national draft, Essendon's second pick overall in the draft. Due to many key players being injured in the 2004 pre-season, Stanton was immediately brought into the Essendon team for the round 1 match against Port Adelaide where the Bombers were comfortably defeated by 96 points. Stanton was the round nomination for the Rising Star after the round 20 win against Collingwood. Stanton started his 2005 season by changing to the number 24 jumper, previously worn by former Essendon great Joe Misiti. Stanton had a strong season, in the 19 games that he played, he averaged 18 possessions and kicked 13 goals. In just his second year of football he showed much improvement from his debut season, Stanton finished third in the 2005 Crichton Medal behind Mark Johnson and Jason Johnson with 253 votes. Stanton worked hard during the pre-season, and was able to increase his physical size. During 2006, he played a different role on the wing, opposite Scott Camporeale. During a horror season which netted only three wins and a draw for Essendon (one of which was against reigning premiers Sydney), Stanton was one of only three players in the team who played in every game that season. Stanton averaged 22 possessions and kicked 12 goals finishing fourth in the 2006 Crichton Medal with 196 votes. Stanton became a far more prominent player for the Bombers in 2007, he averaged a career-high 25 possessions in the first 10 rounds of the season.
Sources: en.wikipedia.org
Dry powder is normally held at -20 °C or lower, away from light and moisture. Sealed vials can also be kept at 2-8 °C for shorter intervals. Warming to room temperature before opening prevents condensation.
In solution, hydrolysis of peptide bonds and oxidation of the methionine residue are the principal concerns. Oxidation converts methionine to its sulfoxide form, shifting the mass by sixteen daltons. Both processes are slowed by cold storage and by avoiding alkaline conditions.
A certificate documents what the supplier measured on a specific lot, not how a laboratory will use the material. Independent verification of identity and purity is common practice. Acceptance criteria should be defined before a batch is ordered.
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.