Everything below concerns Semax. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-05-19. Where a claim depends on a specific study, the study is described rather than over-claimed.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
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.
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 |
|---|---|---|
| Typical analytical method | Reversed-phase HPLC with UV detection | Separates target peptide from truncated and oxidised forms |
| Identity confirmation | LC-MS or ESI-MS | Compares observed and calculated molecular ion |
| Primary degradation route | Methionine oxidation | Forms the sulfoxide; monitored as an early-eluting peak |
| Short-term storage | 2 to 8 degrees Celsius | Applies to working vials and reconstituted portions |
| Common synonyms | ACTH(4–10) analogue, MEHFPGP | Descriptive names used in laboratory catalogues |
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.
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.
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.
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.
Healthy white male volunteers were selected as the typical skin lesions were easier to see in Caucasians and this population was felt to be those least susceptible to the disease, thus provide the strongest evidence that the disease was caused by a nutritional deficiency. Subjects experienced mild, but typical cognitive and gastrointestinal symptoms, and within five months of this cereal-based diet, 6 of the 11 subjects broke out in the skin lesions that are necessary for a definitive diagnosis of pellagra. The lesions appeared first on the scrotum. Goldberger was not given the opportunity to experimentally reverse the effects of diet-induced pellagra, as the prisoners were released shortly after the diagnoses of pellagra were confirmed. In the 1920s, he connected pellagra to the corn-based diets of rural areas rather than infection as contemporary medical opinion would suggest. Goldberger believed that the root cause of pellagra amongst Southern farmers was limited diet resulting from poverty, and that social and land reform would cure epidemic pellagra. His reform efforts were not realized, but crop diversification in the Southern United States, and the accompanying improvement in diet, dramatically reduced the risk of pellagra. Goldberger is remembered as the "unsung hero of American clinical epidemiology". Though he identified that a missing nutritional element was responsible for pellagra, he did not discover the specific vitamin responsible.
=== New Jersey === Because streptomycin was isolated from a microbe discovered on New Jersey soil, and because of its activity against tuberculosis and Gram negative organisms, and in recognition of both the microbe and the antibiotic in the history of New Jersey, S. griseus was nominated as the Official New Jersey state microbe. The draft legislation was submitted by Senator Sam Thompson (R-12) in May 2017 as bill S3190 and Assemblywoman Annette Quijano (D-20) in June 2017 as bill A31900. The bill was passed on 2018-01-08 The bill designates Streptomyces griseus as New Jersey State Microbe (New Jersey Senate Bill 3190 (2017). Governor Phil Murphy signed the bill making it official in 2019.
These two are the heaviest isotopes of dubnium to date, and both were produced as a result of decay of the heavier nuclei 288Mc and 294Ts rather than directly, because the experiments that yielded them were originally designed in Dubna for 48Ca beams. For its mass, 48Ca has by far the greatest neutron excess of all practically stable nuclei, both quantitative and relative, which correspondingly helps synthesize superheavy nuclei with more neutrons, but this gain is compensated by the decreased likelihood of fusion for high atomic numbers.
== Using genomics to infer early lines of evolution == Instead of relying on a single gene such as the small-subunit ribosomal RNA (SSU rRNA) gene to reconstruct early evolution, or a few genes, scientific effort has shifted to analyzing complete genome sequences. Evolutionary trees based only on SSU rRNA alone do not capture the events of early eukaryote evolution accurately, and the progenitors of the first nucleated cells are still uncertain. For instance, analysis of the complete genome of the eukaryote yeast shows that many of its genes are more closely related to bacterial genes than they are to archaea, and it is now clear that archaea were not the simple progenitors of the eukaryotes, in contradiction to earlier findings based on SSU rRNA and limited samples of other genes. One hypothesis is that the first nucleated cell arose from two distinctly different ancient prokaryotic (non-nucleated) species that had formed a symbiotic relationship with one another to carry out different aspects of metabolism. One partner of this symbiosis is proposed to be a bacterial cell, and the other an archaeal cell. It is postulated that this symbiotic partnership progressed via the cellular fusion of the partners to generate a chimeric or hybrid cell with a membrane bound internal structure that was the forerunner of the nucleus. The next stage in this scheme was transfer of both partner genomes into the nucleus and their fusion with one another. Several variations of this hypothesis for the origin of nucleated cells have been suggested.
Sources: en.wikipedia.org
==== Hair clippers ==== Sharp hair clippers are used to shave the animal and expose its bare skin. Close contact between brand and bare skin is much more important in freeze branding than in hot branding. This is due to hair's excellent heat insulation, which can drastically reduce heat flux during cryogenic branding. An animal not being shaved closely enough is the main cause of failed brands.
== Research directions == Key research questions in PMOS focus on the best way to manage the condition, including with new anti-obesity drugs. In terms of criteria for diagnosis, age-specific levels of AMH need to be specified. Biomarkers are needed for early diagnosis and to guide drug development. Another open question is how to define the male phenotype to assess male relatives of women with PMOS. Research is exploring better ways to assess and predict metabolic complications. Current clinical tests for insulin resistance lack accuracy and standardisation, and the gold-standard method is impractical in clinical settings. Emerging approaches include multiomics, which may uncover biomarkers for diagnosis and subtyping, and artificial intelligence (AI)-based methods, which can identify patterns in medical data and also classify patients into subgroups. Combining AI with omics might improve early diagnosis, risk prediction, personalised treatment, and long-term monitoring, though robust validation in large, diverse cohorts remains necessary. As of 2024, studies have successfully developed in vitro PMOS disease models through human embryonic stem cells (hESCs) and induced pluripotent stem cell technology (iPSC). Both can be derived from individuals with PMOS and can differentiate into various cell types. Using adult somatic cells, iPSCs can reprogram the cells into a pluripotent state, which can then be specified to replicate PMOS-like traits.
In chemistry, the biuret test (IPA: , ), also known as Piotrowski's test, is a chemical test used for detecting the presence of at least two peptide bonds in a molecule. In the presence of peptides, a copper(II) ion forms mauve-colored coordination complexes in an alkaline solution. The reaction was first observed in 1833. In Poland, the biuret test is also known as Piotrowski's test in honor of the Polish physiologist Gustaw Piotrowski who independently rediscovered it in 1857. Several variants on the test have been developed, such as the BCA test and the Modified Lowry test. The biuret reaction can be used to assess the concentration of proteins because peptide bonds occur with the same frequency per amino acid in the peptide. The intensity of the color, and hence the absorption at 540 nm, is directly proportional to the protein concentration, according to the Beer–Lambert law. Despite its name, the reagent does not in fact contain biuret [(H2N−CO−)2NH]. The test is so named because it also gives a positive reaction to the peptide-like bonds in the biuret molecule. In this assay, the copper(II) binds with nitrogen atoms present in the peptide bonds of proteins. In a secondary reaction, the copper(II) is reduced to copper(I). Buffers, such as Tris and ammonia interfere with this assay, therefore rendering this assay inappropriate for protein samples purified from ammonium sulfate precipitation. Due to its insensitivity and little interference by free amino acids, this assay is most useful for whole tissue samples and other sources with high protein concentration.
Sources: en.wikipedia.org
On January 17, 2019, Pritzker signed a bill requiring state certification for gun dealers, which passed during the tenure of his predecessor, Bruce Rauner. It also requires gun dealers to ensure the physical security of their stores, to keep a detailed list of items on sale, and employees of such stores to undergo annual training. These requirements come on top of the mandatory federal license issued by the Bureau of Alcohol, Tobacco, Firearms and Explosives. Proponents say Senate Bill 337 prevents guns from falling "into the wrong hands" while opponents argue it creates additional bureaucracy, imposes a financial burden on gun business owners, and will neither enhance public safety nor reduce crime. The Illinois State Rifle Association argued that the bill violates the Second Amendment to the U.S. Constitution because it interferes with the right to bear arms, and filed a lawsuit alongside eight gun dealers. On May 18, 2022, Pritzker signed House Bill 4383, which banned the sale and possession of homemade firearms in Illinois. Illinois became the 11th state and first midwestern state to enact such a policy. On January 11, 2023, Pritzker signed a ban on assault weapons and high-capacity magazines. He said of the legislation, "With this legislation we are delivering on the promises Democrats have made and, together, we are making Illinois's gun laws a model for the nation." The new law took effect immediately, with approximately 2.5 million Illinois gun owners affected.
== See also == Breast hypertrophy – Rare human disease Male bra – Pieces of clothing that fit tightly around the skinPages displaying short descriptions of redirect targets Male lactation – Production of milk in male mammals Mammoplasia – Normal or spontaneous enlargement of breasts
== History == The use of snail slime in cosmetics and pharmaceutical applications dates back to ancient Greece, where it was recommended as a treatment for skin inflammation. Early practices involved crushing secretions from brown garden snails to help alleviate inflammatory skin conditions. This approach is part of a broader tradition known as zootherapy, which has existed since ancient Mesopotamia and Egypt and involves the use of animal-based remedies for healing. Additionally, snails were known to be high in nutrients and as a delicacy to be eaten.
Sources: en.wikipedia.org
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.
Oxidation of the methionine residue to the sulfoxide is a frequently reported change, and it usually appears as an earlier-eluting peak in reversed-phase chromatography. Backbone hydrolysis products can also accumulate in aqueous solution.
Liquid chromatography coupled with mass spectrometry is the usual approach, because the observed molecular ion can be compared with a calculated mass of about 813.9 Da. Retention time alone does not establish identity.
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.