Semax comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-06-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
| 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 |
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.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
=== Generic names === Drostanolone propionate is the generic name of the drug and its BANMTooltip British Approved Name, while dromostanolone propionate is the USANTooltip United States Adopted Name and USPTooltip United States Pharmacopeia; there is no INNTooltip International Nonproprietary Name for this form. The generic name of the unesterified form of the drug is drostanolone or dromostanolone and the former is its INNTooltip International Nonproprietary Name, BANTooltip British Approved Name, and DCFTooltip Dénomination Commune Française while there is no USANTooltip United States Adopted Name.
==== Leaves ==== Edible raw or cooked (depending on hardiness), the leaves can be used in many ways. They are perhaps most commonly added to clear broth-based soups, such as the Filipino dishes tinola and utan. Tender moringa leaves, finely chopped, are used as garnish for vegetable dishes and salads, such as the Kerala dish thoran. It is also used in place of or along with coriander leaves (cilantro). The leaves are also cooked and used in ways similar to spinach, and are commonly dried and crushed into a powder for soups and sauces. For long-term use and storage, moringa leaves may be dried and powdered to preserve their nutrients. Sun, shade, freeze and oven drying at 50–60 °C are all acceptable methods, albeit variable in their retention efficacy of specific micro- and macronutrients. The powder is commonly added to soups, sauces, and smoothies. Owing to its high nutritional density, moringa leaf powder is valued as a dietary supplement and may be used to enrich food products ranging from dairy, such as yogurt and cheese, to baked goods, such as bread and pastries, with acceptable palatability.
Luminol in an alkaline solution with hydrogen peroxide in the presence of iron or copper, or an auxiliary oxidant, produces 3-aminophtalate in an excited state, which exhibits chemiluminescence. The luminol reaction is
Ribosomes are essential for protein synthesis in all living organisms. Prokaryotic and eukaryotic ribosomes both contain a scaffold of ribosomal RNA (rRNA) on which are arrayed an extensive variety of ribosomal proteins (RP). Ribosomopathies can arise from abnormalities of either rRNA or the various RPs. The nomenclature of rRNA subunits is derived from each component's Svedberg unit, which is an ultracentrifuge sedimentation coefficient, that is affected by mass and also shape. These S units of the rRNA subunits cannot simply be added because they represent measures of sedimentation rate rather than of mass. Eukaryotic ribosomes are somewhat larger and more complex than prokaryotic ribosomes. The overall 80S eukaryotic rRNA structure is composed of a large 60S subunit (LSU) and a small 40S subunit (SSU). In humans, a single transcription unit separated by 2 internally transcribed spacers encodes a precursor, 45S. The precursor 45S rDNA is organized into 5 clusters (each has 30-40 repeats) on chromosomes 13, 14, 15, 21, and 22. These are transcribed in the nucleolus by RNA polymerase I. 45S is processed in the nucleus via 32S rRNA to 28S and 5.8S, and via 30S to 18S, as shown in the diagram. 18S is a component of the ribosomal 40S subunit. 28S, 5.8S and 5S, which is transcribed independently, are components of 60S. The 5S DNA occurs in tandem arrays (~200-300 true 5S genes and many dispersed pseudogenes); the largest is on chromosome 1q41-42. 5S rRNA is transcribed by RNA polymerase III.
Each chemical element has a unique atomic number (Z— for "Zahl", German for "number") representing the number of protons in its nucleus. Each distinct atomic number therefore corresponds to a class of atom: these classes are called the chemical elements. The chemical elements are what the periodic table classifies and organizes. Hydrogen is the element with atomic number 1; helium, atomic number 2; lithium, atomic number 3; and so on. Each of these names can be further abbreviated by a one- or two-letter chemical symbol; those for hydrogen, helium, and lithium are respectively H, He, and Li. Neutrons do not affect the atom's chemical identity, but do affect its weight. Atoms with the same number of protons but different numbers of neutrons are called isotopes of the same chemical element. Naturally occurring elements usually occur as mixes of different isotopes; since each isotope usually occurs with a characteristic abundance, naturally occurring elements have well-defined atomic weights, defined as the average mass of a naturally occurring atom of that element. All elements have multiple isotopes, variants with the same number of protons but different numbers of neutrons. For example, carbon has three naturally occurring isotopes: all of its atoms have six protons and most have six neutrons as well, but about one per cent have seven neutrons, and a very small fraction have eight neutrons. Isotopes are never separated in the periodic table; they are always grouped together under a single element.
Sources: en.wikipedia.org
==== Legal Considerations ==== In the United States brands applied by any method often must be registered with a state or county office. In some jurisdictions, it is illegal to brand an animal without first registering the design with a state office. The following table summarizes the legal recognition and requirements for equine freeze brands in the United States:
Because the Solar Wind Spectrometer made continuous measurements, it was possible to measure how the Earth's magnetic field affects arriving solar wind particles. For about two-thirds of each orbit, the Moon is outside of the Earth's magnetic field. At these times, a typical proton density was 10 to 20 per cubic centimeter, with most protons having velocities between 400 and 650 kilometers per second. For about five days of each month, the Moon is inside the Earth's geomagnetic tail, and typically no solar wind particles were detectable. For the remainder of each lunar orbit, the Moon is in a transitional region known as the magnetosheath, where the Earth's magnetic field affects the solar wind, but does not completely exclude it. In this region, the particle flux is reduced, with typical proton velocities of 250 to 450 kilometers per second. During the lunar night, the spectrometer was shielded from the solar wind by the Moon and no solar wind particles were measured. Protons also have extrasolar origin from galactic cosmic rays, where they make up about 90% of the total particle flux. These protons often have higher energy than solar wind protons, and their intensity is far more uniform and less variable than protons coming from the Sun, the production of which is heavily affected by solar proton events such as coronal mass ejections. Research has been performed on the dose-rate effects of protons, as typically found in space travel, on human health.
The pelB leader sequence is a sequence of amino acids which, when attached to a protein, directs the protein to the bacterial periplasm, where the sequence is removed by a signal peptidase. Specifically, pelB refers to pectate lyase B of Erwinia carotovora CE. The leader sequence consists of the 22 N-terminal amino acid residues. This leader sequence can be attached to any other protein (on the DNA level) resulting in a transfer of such a fused protein to the periplasmic space of Gram-negative bacteria, such as Escherichia coli, often used in genetic engineering. Protein secretion can increase the stability of cloned gene products. For instance it was shown that the half-life of the recombinant proinsulin is increased 10-fold when the protein is secreted to the periplasmic space. (vijji. Narne, R.S.Ramya) One of pelB's possible applications is to direct coat protein-antigen fusions to the cell surface for the construction of engineered bacteriophages for the purpose of phage display. The Pectobacterium carotovorum pelB leader sequence commonly used in molecular biology has the sequence MKYLLPTAAAGLLLLAAQPAMA (UniProt Q04085).
9-Carboxymethoxymethylguanine (CMMG) is a compound which is known as the principal metabolite of the antiviral medication aciclovir (and its prodrug valaciclovir), and has been suggested as the causative agent in the neuropsychiatric side effects sometimes associated with these medications. These are mainly suffered by patients with kidney failure or otherwise decreased kidney function, and can include psychotic reactions, hallucinations, and rarely more complex disorders such as Cotard delusion. Patients suffering these symptoms following aciclovir treatment were found to have much higher levels of CMMG than normal, and since this is the first time Cotard delusion has been linked to a drug as a side effect, this discovery may be useful in the study of Cotard delusion and its treatment.
Sources: en.wikipedia.org
=== Quantitative analysis === Quantitative approach requires large number of grain analyses within a sample rock in order to represent the overall detrital zircon population statistically (i.e. the total number of analyses should achieve an appropriate level of confidence). Because of the large sample size, secondary ion mass spectrometry (SIMS) and laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) are used instead of thermal ionization mass spectrometry (TIMS). In this case, BSE and CL imagery are applied to select the best spot on a zircon grain for acquiring reliable age.
== History == Famotidine was developed by Yamanouchi Pharmaceutical Co. It was licensed in the mid-1980s by Merck & Co. and is marketed by a joint venture between Merck and Johnson & Johnson. The imidazole ring of cimetidine was replaced with a 2-guanidinothiazole ring. Famotidine proved to be nine times more potent than ranitidine, and thirty-two times more potent than cimetidine. It was first marketed in 1981. Pepcid RPD orally disintegrating tablets were released in 1999. Generic preparations became available in 2001, e.g. Fluxid (Schwarz) or Quamatel (Gedeon Richter Ltd.). In the United States and Canada, a product called Pepcid Complete, which combines famotidine with an antacid in a chewable tablet to relieve the symptoms of excess stomach acid quickly, is available. In the UK, this product was known as PepcidTwo until its discontinuation in April 2015. Famotidine has poor bioavailibility (50%) due to its low solubility in the high pH of the intestines. Researchers are developing formulations that use gastroretentive drug delivery systems such as floating tablets to increase bioavailability by promoting local delivery (directly into the stomach wall) of these drugs to receptors in the parietal cell membrane.
31 May: David Seymour succeeds Winston Peters as deputy prime minister, under the terms of the coalition agreement in 2023. Strong winds cause power outages in parts of Otago and the Southland Region.
== Reversed phase SPE == Reversed phase SPE separates analytes based on their polarity. The stationary phase of a reversed phase SPE cartridge is derivatized with hydrocarbon chains, which retain compounds of mid to low polarity due to the hydrophobic effect. The analyte can be eluted by washing the cartridge with a non-polar solvent, which disrupts the interaction of the analyte and the stationary phase. A stationary phase of silicon with carbon chains is commonly used. Relying on mainly non-polar, hydrophobic interactions, only non-polar or very weakly polar compounds will adsorb to the surface.
== Pathophysiology == Hutchinson–Gilford progeroid syndrome (HGPS) is an extremely rare autosomal dominant genetic disorder in which symptoms resembling aspects of aging are manifested at an early age. Its occurrence is usually the result of a sporadic germline mutation; although HGPS is genetically dominant, people rarely live long enough to have children, preventing them from passing the disorder on in a hereditary manner.
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 synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.