A practical reference on Neurotrophic signalling: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-02-24 and is reviewed periodically as new material appears.
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.
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.
| 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 |
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
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.
At the third AU summit, held in Tripoli, Libya, in July 2005, Gaddafi called for greater integration, advocating a single AU passport, a common defence system, and a single currency, using the slogan: "The United States of Africa is the hope." His proposal for a Union of African States, a project originally conceived by Ghana's Kwame Nkrumah in the 1960s, was rejected at the 2001 Assembly of Heads of States and Government (AHSG) summit in Lusaka by African leaders who thought it "unrealistic" and "utopian". In June 2005, Libya joined the Common Market for Eastern and Southern Africa (COMESA). In March 2008 in Uganda, Gaddafi gave a speech once again urging Africa to reject foreign aid. In August 2008, Gaddafi was proclaimed "King of Kings" by a committee of traditional African leaders; they crowned him in February 2009, in a ceremony held in Addis Ababa, Ethiopia. That same month, Gaddafi was elected as the chairperson of the African Union, a position he retained for one year. In October 2010, Gaddafi apologized to African leaders for the historical enslavement of Africans by the Arab slave trade.
=== Career === In 1989 he was appointed assistant professor at Harvard University where he studied the interaction of the potassium channel with a specific toxin derived from scorpion venom, acquainting himself with methods of protein purification and X-ray crystallography. In 1996 he moved to Rockefeller University as a professor and head of the Laboratory of Molecular Neurobiology and Biophysics where he started to work on the structure of the potassium channel. These channels are of particular importance to the nervous system and the heart and enable potassium ions to cross the cell membrane.
== Diabetes / Insulin Tutorial == There is an abundance of textual / static graphical information about insulin and diabetes on the web. However an AIDA-based Diabetes / Insulin Tutorial has been developed. The tutorial is unusual in that — in addition to offering textual / static graphical information about insulin and diabetes — it is also integrated with the AIDA on-line web-based diabetes simulator. In this way, visitors can not only read about insulin dosage adjustment in diabetes, but also interactively simulate examples of what they are learning about. The tutorial is currently arranged in four sections: (1) Insulin-dosage adjustment, (2) Choosing the insulin dose, (3) Timing of meals & diet planning, and (4) Glucose & the kidney.
== Cosmeses == Certain hair shampoos and ointments visually thicken existing hair, without affecting the growth cycle. There have also been developments in the fashion industry with wig design. The fashion accessory has also been shown to be a source of psychological support for women undergoing chemotherapy, with cancer survivors in one study describing their wig as a "constant companion". Other studies in women have demonstrated a more mixed psychosocial impact of hairpiece use. Specialized tattoos, commonly known as scalp micropigmentation, can mimic the appearance of a short buzzed haircut.
In the early part of 1982, Carrey reportedly performed for The Tonight Show bookers Jim McCawley and Bud Robinson as part of the program's audition process for stand-up comic spots. However, rather than being booked on the show, Carrey got advised to further hone his act, so he went back home to the Toronto area where he had already built a significant following. Touring venues throughout North America as the opening act for Rodney Dangerfield, Carrey made a stop at home in Toronto on June 19, 1982, performing two sold-out shows at Massey Hall.
Sources: en.wikipedia.org
Deborah Kay Dunn-Walters FMedSci (born September 1963) is a British immunologist who is Professor of Immunology and Associate Dean for Research and Innovation at the University of Surrey. Her research considers B-cell development in healthy ageing and in disease, particularly from the viewpoint of antibody repertoires. During the COVID-19 pandemic, Dunn-Walters focussed on mapping responses to SARS-CoV-2 infection and the development of single cell analyses of the immunological responses to a COVID-19 vaccine. She was a member of the Scientific Advisory Group for Emergencies, and provided the government with scientific advice during the pandemic.
On the other hand, other than the lightest nuclides, nuclides with an odd number of protons and an odd number of neutrons (odd Z, odd N) are usually short-lived (a notable exception is neptunium-236 with a half-life of 154,000 years) because they readily decay by beta-particle emission to their isobars with an even number of protons and an even number of neutrons (even Z, even N) becoming much more stable. The physical basis for this phenomenon also comes from the pairing effect in nuclear binding energy, but this time from both proton–proton and neutron–neutron pairing. The relatively short half-life of such odd-odd heavy isotopes means that they are not available in quantity and are highly radioactive. According to the fissility rule proposed by Yigal Ronen, for a heavy element with Z between 90 and 100, an isotope is fissile if and only if 2 × Z − N ∈ {41, 43, 45} (where N = number of neutrons and Z = number of protons), with a few exceptions. This rule holds for all but fourteen nuclides – seven that satisfy the criterion but are nonfissile, and seven that are fissile but do not satisfy the criterion.
== Function == Pepsinogen is activated into the digestive enzyme pepsin when it comes in contact with hydrochloric acid produced by gastric parietal cells. This type of cell also secretes gastric lipase enzymes, which help digest triglycerides into free fatty acids and di- and mono-glycerides. There is also evidence that the gastric chief cell secretes leptin in response to the presence of food in the stomach. Leptin has been found in the pepsinogen granules of chief cells. Chief cells also produce the acidic mammalian chitinase (CHIA, AMCase), a chitin-digesting enzyme resistant to pepsin digestion. AMCase production requires a local type 2 immune response.
His dialogue sounds composed entirely of sentences memorized from tourist phrase books." Mark Olsen of the Los Angeles Times wrote that "All of the film's purposeful weirdness is conveyed with an unaffected simplicity that recalls the dead-aim haphazard compositions of photographer William Eggleston", concluding that, "as a film, it's pure and singular, but it's not quite fully formed enough to be what one could call truly visionary." A. O. Scott of The New York Times wrote that the film "at times seems as much an exercise in perversity as an examination of it", and that "The static wide-screen compositions are beautiful and strange, with the heads and limbs of the characters frequently cropped. The light is gauzy and diffuse, helping to produce an atmosphere that is insistently and not always unpleasantly dreamlike. You might think of paintings by Balthus or maybe Alex Katz, though the implied stories in those pictures are more genuinely evocative and haunting than the actual narrative of Dogtooth." Several reviewers, such as Harkness and Bradshaw, made comparisons to the 2008 Fritzl case, although they noted that the screenplay was written before the case emerged. Scott, like Ebert, made references to homeschooling. The film's larger meaning eluded easy expression. Scott called the film "a conversation piece. Though the conversation may... be more along the lines of: 'What was that?' 'I don't know. Weird.' 'Yeah.' [shudder].
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.
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.