The short version of Peptide mapping fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-07-29. Anything still debated is marked as such rather than presented as settled.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
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.
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.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
== External links == Chorionic+Gonadotropin at the U.S. National Library of Medicine Medical Subject Headings (MeSH) "History of pregnancy test". U.S. National Institutes of Health. Archived from the original on 2011-01-13. Retrieved 2011-01-10.
Vehicle accidents (cars, motorcycles, bicycles, trains, etc.) Labor accidents (equipment, instruments, cylinders, chainsaws, press machines, meat machines, wood machines, etc.) Agricultural accidents, with machines and mower equipment Electric shock hazards Firearms, bladed weapons, explosives Violent rupture of ship rope or industry wire rope Ring traction (ring amputation, de-gloving injuries) Building doors and car doors Animal attacks Gas cylinder explosions Other rare accidents
Li R, Bianchet MA, Talalay P, Amzel LM (1995). "The three-dimensional structure of NAD(P)H:quinone reductase, a flavoprotein involved in cancer chemoprotection and chemotherapy: mechanism of the two-electron reduction". Proc. Natl. Acad. Sci. U.S.A. 92 (19): 8846–50. Bibcode:1995PNAS...92.8846L. doi:10.1073/pnas.92.19.8846. PMC 41064. PMID 7568029.
Sources: en.wikipedia.org
Francisco Rodríguez, an economist, called on Venezuela's National Assembly to reject the deal, describing it as "predatory" and arguing that transferring Venezuelan oil wealth to the United States was unconstitutional and not in the country's interest, particularly when carried out under the threat of force. Gregory Brew, an energy historian and analyst at the Eurasia Group, expressed skepticism about the agreement, predicting significant opposition to any deal that would give the U.S. government effective control over Venezuelan resources. He compared the arrangement to the early 20th-century control exercised by the Anglo-Persian Oil Company over oil resources in Iraq and Iran, and suggested that for Trump, control over oil appeared to be an objective in itself, with the arrangement carrying colonial overtones. On 31 August, The New York Times reported that the arrangement would give the Defense Department the option to acquire up to 35 per cent of the parent company of Betancourt's firm through a warrant, described by two people familiar with the deal as a penny warrant convertible into shares for as little as one cent. The White House said the same day that the partnership came "all at zero cost to the United States", that the federal government would be guaranteed 20 per cent of the company's output at production cost with the State Department holding a right of first refusal over the remainder, and that the United States would hold a veto over appointments to the company's board, a majority of whose members would have to be American citizens.
== Ecology == Parmotrema perlatum is an important species within specific lichen communities in British woodlands, particularly those in late successional mesotrophic settings in oceanic or humid microclimates. It is associated with the Type K Lobaria pulmonaria-Isothecium myosuroides ecological community. This community type is characterised by its occurrence in mature mesotrophic environments, which are often warmer in winter climates or specific microhabitats. This community includes, in addition to P. perlatum, dominant foliose lichens like Lobaria pulmonaria, Hypotrachyna taylorensis, and Parmotrema crinitum, as well as bryophytes such as Isothecium myosuroides. A 2017 study investigated the physiological responses of Parmotrema perlatum along an aridity gradient in Southern Portugal. The researchers transplanted thalli of P. perlatum to rural and forested sites characterised by varying levels of aridity and measured several physiological parameters, including photosynthetic performance, pigment content, ergosterol content, and sample viability, both before and after a six-month exposure period. The study found that P. perlatum showed lower photosynthetic performance (measured as FV/FM and the performance index on an absorption basis, PIABS) in drier sites compared to more humid sites. In humid environments, the content of photosynthetic pigments increased post-exposure, while in drier sites, this increase was less pronounced. Additionally, ergosterol content was lower in drier sites, indicating a stress response to arid conditions. These results highlight that P.
=== Mechanism of action === Omeprazole is a selective and irreversible proton pump inhibitor. It suppresses stomach acid secretion by specific inhibition of the H+/K+-ATPase system found at the secretory surface of gastric parietal cells. Because this enzyme system is regarded as the acid (proton, or H+) pump within the gastric mucosa, omeprazole inhibits the final step of acid production. Omeprazole also inhibits both basal and stimulated acid secretion irrespective of the stimulus as it blocks the last step in acid secretion. The drug binds non-competitively so it has a dose-dependent effect. The inhibitory effect of omeprazole occurs within one hour after oral administration. The maximum effect occurs within two hours. The duration of inhibition is up to 72 hours. When omeprazole is stopped, baseline stomach acid secretory activity returns after three to five days. The inhibitory effect of omeprazole on acid secretion will plateau after four days of repeated daily dosing. Omeprazole is only effective on active H+/K+-ATPase pumps. These pumps are stimulated in the presence of food to aid in digestion.
Sources: en.wikipedia.org
Filament notching is due to uneven evaporation of the filament. Small variations in resistivity along the filament cause "hot spots" to form at points of higher resistivity; a variation of diameter of only 1% will cause a 25% reduction in service life. Since filament resistance is highly temperature-dependent, spots with higher temperature will have higher resistance, causing them to dissipate more energy, making them hotter – a positive feedback loop. These hot spots evaporate faster than the rest of the filament, permanently increasing the resistance at that point. The process ends in the familiar tiny gap in an otherwise healthy-looking filament. Lamps operated on direct current develop random stairstep irregularities on the filament surface which may cut lifespan in half compared to AC operation; different alloys of tungsten and rhenium can be used to counteract the effect. Since a filament breaking in a gas-filled bulb can form an electric arc, which may spread between the terminals and draw very heavy current, intentionally thin lead-in wires or more elaborate protection devices are therefore often used as fuses built into the light bulb. More nitrogen is used in higher-voltage lamps to reduce the possibility of arcing.
For one thing, because there is an extra NADPH-catalyzed reduction, this can contribute to depletion of cellular stores of NADPH and also reduce levels of alpha-ketoglutarate available to the cell. In particular, the depletion of NADPH is problematic because NADPH is highly compartmentalized and cannot freely diffuse between the organelles in the cell. It is produced largely via the pentose phosphate pathway in the cytoplasm. The depletion of NADPH results in increased oxidative stress within the cell as it is a required cofactor in the production of GSH, and this oxidative stress can result in DNA damage. There are also changes on the genetic and epigenetic level through the function of histone lysine demethylases (KDMs) and ten-eleven translocation (TET) enzymes; ordinarily TETs hydroxylate 5-methylcytosines to prime them for demethylation. However, in the absence of alpha-ketoglutarate this cannot be done and there is hence hypermethylation of the cell's DNA, serving to promote epithelial-mesenchymal transition (EMT) and inhibit cellular differentiation. A similar phenomenon is observed for the Jumonji C family of KDMs which require a hydroxylation to perform demethylation at the epsilon-amino methyl group. Additionally, the inability of prolyl hydroxylases to catalyze reactions results in stabilization of hypoxia-inducible factor alpha, which is necessary to promote degradation of the latter (as under conditions of low oxygen there will not be adequate substrate for hydroxylation).
Iraqi commandos infiltrated the Kuwaiti border first to prepare for the major units, which began the attack at midnight. The Iraqi attack had two prongs, with the primary attack force driving south straight for Kuwait City down the main highway, and a supporting attack force entering Kuwait farther west, but then turning and driving east, cutting off Kuwait City from the country's southern half. The commander of a Kuwaiti armored battalion, 35th Armoured Brigade, deployed them against the Iraqi attack and conducted a robust defense at the Battle of the Bridges near Al Jahra, west of Kuwait City. Kuwaiti aircraft scrambled to meet the invading force, but approximately 20% were lost or captured. A few combat sorties were flown against Iraqi ground forces. The main Iraqi thrust into Kuwait City was conducted by commandos deployed by helicopters and boats to attack the city from the sea, while other divisions seized the airports and two airbases. The Iraqis attacked the Dasman Palace, the Royal Residence of Kuwait's emir, Jaber Al-Ahmad Al-Jaber Al-Sabah, which was defended by the Emiri Guard supported with M-84 tanks. In the process, the Iraqis killed Fahad Al-Ahmed Al-Jaber Al-Sabah, the Emir's youngest brother. Within 12 hours, most resistance had ended within Kuwait, and the royal family had fled, allowing Iraq to control most of Kuwait. After two days of intense combat, most of the Kuwaiti military were either overrun by the Iraqi Republican Guard, or had escaped to Saudi Arabia. The emir and key ministers fled south along the highway for refuge in Saudi Arabia.
Sources: en.wikipedia.org
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.