Neurotrophic signalling is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-02-12. Where a claim depends on a specific study, the study is described rather than over-claimed.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
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.
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 peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
=== Breastfeeding === ACE inhibitors may be used with caution during breastfeeding due to evidence showing small amounts being present in breastmilk. Enalapril is most commonly prescribed and has the most data published. The medications are considered safe for the mother.
Bilawal Bhutto Zardari (born 21 September 1988) is a Pakistani politician who served as the 37th Minister of Foreign Affairs from 2022 to 2023. He became the chairman of the Pakistan People's Party in 2007 following his mother's assassination. Born in Karachi, Sindh, Bilawal maternally belongs to the Bhutto family and paternally to the Zardari family, he is the son of former Prime Minister Benazir Bhutto and President Asif Ali Zardari, and the grandson of former President Zulfikar Ali Bhutto. Bilawal Zardari was a member of the National Assembly of Pakistan from 2018 to 2023. He was re-elected as a Member of the National Assembly of Pakistan in the 2024 Pakistani general election from newly formed constituency NA-194 Larkana-I, taking oath in 2024.
Over the following decades, Article 370 was steadily diluted through presidential orders that extended various provisions of the Indian constitution to the state without full legislative consent, weakening its autonomy. This deepened political disillusionment, particularly in the Kashmir Valley. In 1965, through a Presidential Order, the Bakshi Ghulam Mohammad-led Congress government in Jammu and Kashmir amended the constitution to replace the titles of Prime Minister and Sadr-e-Riyasat with Chief Minister and Governor, aligning them with other Indian states. Abdullah was released in 1968 and, following the Indira–Sheikh Accord of 1975, returned to power as chief minister after a political reconciliation with the central government. After his death in 1982, unrest and violence persisted in the Kashmiri Valley and, following a disputed state election in 1987, an insurgency persisted in protest over autonomy and rights. In the early 1990s, amid the rise of militancy and targeted violence, a mass exodus of Kashmiri Hindus occurred from the Kashmir Valley. Through the 1990s and 2000s, the region witnessed prolonged violence between insurgent groups and Indian security forces. While Article 370 had come to be seen as effectively permanent, it historically faced ideological opposition. In the 1950s, Syama Prasad Mookerjee, founder of the Bharatiya Jana Sangh (BJS), opposed Article 370 on grounds that it hindered national integration and created unequal constitutional treatment.
RSH + SO2Cl2 → RSCl + HCl + SO2 Occasionally, sulfinyl chlorides result from such reactions. SO2Cl2 can also convert alcohols to alkyl chlorides. In industry, sulfuryl chloride is most used in producing pesticides. Phosphorus pentachloride is prepared by the reaction of white phosphorus with sulfuryl chloride. Sulfuryl chloride can also be used to treat wool to prevent shrinking.
==== Psychosis ==== Cocaine has a similar potential to induce temporary psychosis with more than half of cocaine abusers reporting at least some psychotic symptoms at some point. Typical symptoms include paranoid delusions that they are being followed and that their drug use is being watched, accompanied by hallucinations that support the delusional beliefs. Delusional parasitosis with formication ('cocaine bugs') is also a fairly common symptom. Cocaine-induced psychosis shows sensitization toward the psychotic effects of the drug. This means that psychosis becomes more severe with repeated intermittent use.
Sources: en.wikipedia.org
After tobacco is harvested, it is cured (dried), and then aged to improve its flavor. There are four common methods of curing tobacco: air curing, fire curing, flue curing, and sun curing. The curing method used depends on the type of tobacco and its intended use. Air-cured tobacco is sheltered from wind and sun in a well-ventilated barn, where it air-dries for six to eight weeks. Air-cured tobacco is low in sugar, which gives the tobacco smoke a light, sweet flavour, and high in nicotine. Cigar and burley tobaccos are air-cured. In fire curing, smoke from a low-burning fire on the barn floor permeates the leaves. This gives the leaves a distinctive smoky aroma and flavor. Fire curing takes three-to-ten weeks and produces a tobacco low in sugar and high in nicotine. Pipe tobacco, chewing tobacco, and snuff are fire-cured. Flue-cured tobacco is kept in an enclosed barn heated by flues (pipes) of hot air, but the tobacco is not directly exposed to smoke. This method produces cigarette tobacco that is high in sugar and has medium-to-high levels of nicotine. It is the fastest method of curing, requiring about a week. Virginia tobacco that has been flue-cured is also called bright tobacco, because flue curing turns its leaves gold, orange, or yellow. Sun-cured tobacco dries uncovered in the sun. This method is used in Greece, Turkey, and other Mediterranean countries to produce oriental tobacco. Sun-cured tobacco is low in sugar and nicotine and is used in cigarettes.
Dopamine receptors (subtypes D1, D2, D3 and D4), which account for its different antipsychotic properties on productive and unproductive symptoms, in the mesolimbic dopamine system accounts for the antipsychotic effect whereas the blockade in the nigrostriatal system produces the extrapyramidal effects Serotonin receptors (5-HT2, 5-HT6 and 5-HT7), with anxiolytic, antidepressant and antiaggressive properties as well as an attenuation of extrapyramidal side effects, but also leading to weight gain and ejaculation difficulties. Histamine receptors (H1 receptors, accounting for sedation, antiemetic effect, vertigo, and weight gain) α1- and α2-adrenergic receptors (accounting for sympatholytic properties, lowering of blood pressure, reflex tachycardia, vertigo, sedation, hypersalivation and incontinence as well as sexual dysfunction, but may also attenuate pseudoparkinsonism – controversial. Also associated with weight gain as a result of blockage of the adrenergic alpha 1 receptor as well as with intraoperative floppy iris syndrome due to its effect on the iris dilator muscle. M1 and M2 muscarinic acetylcholine receptors (causing anticholinergic symptoms such as dry mouth, blurred vision, constipation, difficulty or inability to urinate, sinus tachycardia, electrocardiographic changes and loss of memory, but the anticholinergic action may attenuate extrapyramidal side effects). The presumed effectiveness of the antipsychotic drugs relied on their ability to block dopamine receptors.
Around the acquisition of Twitter by Elon Musk (27 Oct), interest in alternatives to the site – described as "one of the world's most high-profile information ecosystems", a contemporary suboptimal public square, and as heavily used by many journalists and news media – increases substantially. However, no alternative such as Mastodon, Reddit or the Bluesky protocol was found to match its features such as ease of use to date, in terms of being able to substitute the site. Two studies demonstrate platform-built-in as well browser-integrated misinformation mitigation (11 Nov). Researchers develop falsity scores for over 800 contemporary elites on Twitter and associated exposure scores (21 Nov). News outlets report about the first fully self-supervised anti–money laundering AI software using contemporary suboptimal datasets, LaundroGraph (24 Nov/26 Oct). 11 November – The Global Carbon Project reports that carbon emissions in 2022 remain at record levels, with no sign of the decrease that is needed to limit global warming to 1.5 °C. At the current rate, the carbon that can still be emitted while still meeting the 1.5 °C global goal will likely (at a 50% chance) be emitted within only around nine years. 12 November – Astronomers, using the Hubble Space Telescope, report the discovery of one of the most metal-poor galaxies known. This nearby dwarf galaxy, 20 million light-years away and 1,200 light-years across, is named HIPASS J1131–31 (nicknamed the "Peekaboo" galaxy).
C-4 (explosive), a high explosive solid C4, butyl-type hydrocarbon chain, a type of four-carbon molecule, especially in C4 reversed-phase chromatography columns Cluster 4, an ESA satellite that studies the Earth's magnetosphere over the course of an entire solar cycle C-4 Protective Mask, standard issue gas mask of the Canadian Armed Forces
Sources: en.wikipedia.org
== Affected drugs == Researchers have identified over 85 drugs with which grapefruit reacts adversely. According to a review done by the Canadian Medical Association, there is an increase in the number of potential drugs that can interact with grapefruit juice, and of the number of fruit types that can interact with those drugs. From 2008 to 2012, the number of drugs known to potentially interact with grapefruit, with risk of harmful or even dangerous effects (gastrointestinal bleeding, nephrotoxicity), increased from 17 to 43.
The generation of a protein sequence is much easier than the determination of a protein structure. However, the structure of a protein gives much more insight in the function of the protein than its sequence. Therefore, a number of methods for the computational prediction of protein structure from its sequence have been developed. Ab initio prediction methods use just the sequence of the protein. Threading and homology modeling methods can build a 3-D model for a protein of unknown structure from experimental structures of evolutionarily-related proteins, called a protein family. Predictive machine learning-based approaches tackle the structure problem at multiple levels. At the 1D level, secondary structure and solvent accessibility are predicted. The 2D level works on distances and points of contact along the protein chain; these predictions are orientation independent. At the 3D level, the coordinates of all the atoms in the protein are estimated; this level is the primary goal of most prediction efforts. Finally, the 4D level predicts complexes of multiple proteins. Progress at these levels is assessed annually at the biannual Critical Assessment of Structure Prediction event. The results from structure studies can be fed in to machine learning techniques deployed to understand protein-protein interactions.
=== Plasma in clinical diagnosis === Plasma contains an abundance of proteins many of which can be used as biomarkers, indicating the presence of certain diseases in an individual. Currently, 2D Electrophoresis is the primary method for discovery and detection of biomarkers in plasma. This involves the separation of plasma proteins on a gel by exploiting differences in their size and pI. Potential disease biomarkers may be present in plasma at very low concentrations, so, plasma samples must undergo preparation procedures for accurate results to be obtained using 2D Electrophoresis. These preparation procedures aim to remove contaminants that may interfere with detection of biomarkers, solubilize the proteins so they are able to undergo 2D Electrophoresis analysis, and prepare plasma with minimal loss of low concentration proteins, but optimal removal of high abundance proteins. The future of laboratory diagnostics are headed toward lab-on-a-chip technology, which will bring the laboratory to the point-of-care. This involves integration of all of the steps in the analytical process, from the initial removal of plasma from whole blood to the final analytical result, on a small microfluidic device. This is advantageous because it reduces turn around time, allows for the control of variables by automation, and removes the labor-intensive and sample wasting steps in current diagnostic processes.
It combines peptide-coated iron oxide attached to "reporter chemicals". When a peptide binds to a thrombin molecule, the report is released and appears in the urine where it can be detected. Human testing has not been conducted.
Higher pressure than CCC (typical operation pressures of 40–160 bar vs 5–25 bar) As the pressure drops on the LiLiChro's rotor with the new cells is less than 10bar, this disadvantage has been overcome by the technology and the all-new rotary union seals will last for years of continuous use. Rotary seal wear over time
Sources: en.wikipedia.org
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.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
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.