ACTH fragment 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 2025-10-15. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
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.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Pathology Messaging Implementation Project (PMIP) is the project that introduced universal delivery of electronic pathology results to GPs in Great Britain. The resulting standard was formalised in 2003 as ISB 1557. It uses UN-EDIFACT based messages. More than 20 years later it remains extensively used by the British National Health Service (NHS) to transmit pathology orders and pathology test results. PMIP began in the United Kingdom as the PMEP (Pathology Messaging Enabling Project) under the control of the NHS Information Authority and was supported by the Royal College of Pathologists (Dr Rick Jones), the Royal College of GPs (Dr Stephen Pill) and the British Medical Association. PMIP was designed for the transmission of structured pathology orders and their associated results between pathology and primary care systems. The message definition followed the work on standardisation led by Dr Jonathan Kay and Dr John McVittie and was implemented in UN-EDIFACT as required at the time by the Department of Health. Originally messages were to be encrypted end-to-end (organisation-to-organisation) using public key infrastructure (PKI). The NHS subsequently moved to an alternative strategy using Data Transfer Service (DTS). Messages are encrypted from the pathology laboratory to the DTS server, and again from the DTS server to the General Practitioner using the PMIP interim messaging cryptographic service. The DTS provides application-to-application messaging within the NHS as well as providing a replacement for the X.400 service.
In college basketball, the NCAA Division I men's and women's tournaments will expand to 76 teams beginning next year. The Pentagon releases declassified documents about UFOs and extraterrestrial life. May 10 – Six people are found dead inside a boxcar on a Union Pacific freight train in Laredo, Texas. May 12 2025–2026 United States redistricting: The Republican-led South Carolina Senate rejects redistricting efforts to redraw the congressional districts in South Carolina, including efforts to eliminate the seat represented by congressman Jim Clyburn. American autonomous driving technology company Waymo recalls 3,800 robotaxis over risks that they could enter flooded areas.
Another strategy for site-specific amine conjugation to proteins is to replace lysine residues with arginine residues (LDVs). If all lysines are depleted then the only remaining free amine is at the amino terminus (N-terminus) of the protein. In the case where the protein is an antibody Fc domain, a recombinant LDV Fc can still be purified using protein A. LDV Fc proteins fused with short peptide targeting sequences can be used to deliver conjugated payloads, including nanoparticles, to specific cell surface proteins. The majority of ADCs under development or in clinical trials are for oncological and hematological indications. This is primarily driven by the inventory of monoclonal antibodies, which target various types of cancer. However, some developers are looking to expand the application to other important disease areas.
Several artificial nucleobases have been synthesized, and successfully incorporated in the eight-base DNA analogue named Hachimoji DNA. Dubbed S, B, P, and Z, these artificial bases are capable of bonding with each other in a predictable way (S–B and P–Z), maintain the double helix structure of DNA, and be transcribed to RNA. Their existence could be seen as an indication that there is nothing special about the four natural nucleobases that evolved on Earth. On the other hand, DNA is tightly related to RNA which does not only act as a transcript of DNA but also performs as molecular machines many tasks in cells. For this purpose it has to fold into a structure. It has been shown that to allow to create all possible structures at least four bases are required for the corresponding RNA, while a higher number is also possible but this would be against the natural principle of least effort.
Sources: en.wikipedia.org
=== Pyrolysis === In the typical operating temperature range of e-cigarettes (250–400 °C (482–752 °F)), 25–52% of CBD is transformed into other chemical substances: Δ9-THC, Δ8-THC, cannabinol and cannabichromene as predominant pyrolysates. From a chemical point of view, CBD in e-cigarettes can be considered a precursor of THC.
In 2023, Vasquez introduced bipartisan legislation aimed at addressing the teacher shortage in Indian Country. The bill proposed providing federal pension benefits to educators working in tribal schools, seeking to improve teacher retention and support Native American students. Vasquez voted that year in favor of requiring healthcare workers to receive the COVID-19 vaccine. The following day, he opposed a resolution to end the COVID-19 national emergency. On women's health, he has supported abortion rights and advocated for codifying Roe v. Wade into federal law. In 2024, Vasquez voted in favor of the Protecting Americans from Foreign Adversary Controlled Applications Act, sometimes called the TikTok ban, which sought to address concerns over data security and foreign influence. On July 19, he called for President Joe Biden to withdraw from the 2024 presidential election, citing concerns over his age and ability to campaign effectively. In December 2025, NBC News and The New York Times reported that Vasquez had voted against a bill to reopen the federal government and then touted the money the bill delivered to his district. After the federal government was reopened, primarily with Republican votes, after a 43-day shutdown, Vasquez was among Democrats who "claimed credit for some provisions in the bill." Former Speaker Nancy Pelosi coined the term "vote no and take the dough" when Republicans took credit for money brought to their districts under bills they opposed.
== Uses == Industry, agriculture, and other sectors employ many poisonous substances, usually for reasons other than their toxicity to humans. Examples include medicines (e.g. anthelmintics used on chickens), solvents (e.g. rubbing alcohol, turpentine), cleaners (e.g. bleach, ammonia), coatings (e.g. arsenic wallpaper), and feedstocks. The toxicity itself sometimes has economic value, when it serves agricultural purposes such as weed control and pest control. Most poisonous industrial compounds have associated material safety data sheets and are classified as hazardous substances. Hazardous substances are subject to extensive regulation on production, procurement, and use in overlapping domains of occupational safety and health, public health, drinking water quality standards, air pollution, and environmental protection. Due to the mechanics of molecular diffusion, many poisonous compounds rapidly diffuse into biological tissues, air, water, or soil on a molecular scale. By the principle of entropy, chemical contamination is typically costly or infeasible to reverse, unless specific chelating agents or micro-filtration processes are available. Chelating agents are often broader in scope than the acute target, and therefore their ingestion necessitates careful medical or veterinarian supervision. Pesticides are one group of substances whose prime purpose is their toxicity to various insects and other animals deemed to be pests (e.g., rats and cockroaches). Natural pesticides have been used for this purpose for thousands of years (e.g.
=== Others === A number of fusion proteins belong to none of the three main classes. Poxviruses employ a multiprotein system of 11 different genes and their relatives in the broader group of Nucleocytoviricota appear to do likewise. The structure of the fusion complex is not yet resolved. Scientists have produced some information on what each of the components bind to, but still not enough to produce a full picture. Hepadnaviridae, which includes the Hep B virus, uses different forms of the surface antigen (HBsAg - S, M and L) to fuse. It was found in 2021 that it has a fusion peptide in preS1, which is found in the L form.
=== Notable product use === Bruker products are used globally in a variety of situations. The National High Magnetic Field Laboratory at Florida State University selected Bruker to build the world's first 21.0 tesla FT-ICR MS. The Total Carbon Column Observing Network uses high resolution FT-IR spectrometers made by Bruker to measure various greenhouse gases across the globe.
Sources: en.wikipedia.org
The peer-reviewed journal facilitated discourse around regenerative medicine by publishing innovative research on stem cell therapies, gene therapies, tissue engineering, and biomechanical prosthetics. The Society for Regenerative Medicine, later renamed the Regenerative Medicine and Stem Cell Biology Society, served a similar purpose, creating a community of like-minded experts from around the world. In June 2008, at the Hospital Clínic de Barcelona, Professor Paolo Macchiarini and his team, of the University of Barcelona, performed the first tissue engineered trachea (wind pipe) transplantation. Adult stem cells were extracted from the patient's bone marrow, grown into a large population, and matured into cartilage cells, or chondrocytes, using an adaptive method originally devised for treating osteoarthritis. The team then seeded the newly grown chondrocytes, as well as epithelial cells, into a decellularised (free of donor cells) tracheal segment that was donated from a 51-year-old transplant donor who had died of cerebral hemorrhage. After four days of seeding, the graft was used to replace the patient's left main bronchus. After one month, a biopsy elicited local bleeding, indicating that the blood vessels had already grown back successfully. In 2009, the SENS Foundation was launched, with its stated aim as "the application of regenerative medicine – defined to include the repair of living cells and extracellular material in situ – to the diseases and disabilities of ageing".
) is 2.4×1034 years (in the decay channel into a positron and a neutral pion: p → e+ + π0). According to the Standard Model, the proton, a type of baryon, is stable because baryon number is conserved. Since protons are the lightest baryons in the model, they cannot decay into other particles on their own and are therefore stable. However, baryon number conservation is an accidental global symmetry of the Standard Model, not associated with any fundamental gauge symmetry, slightly violated by non-perturbative SU(2)L sphaleron effects, negligible at low temperatures but relevant in the early Universe. Positron emission and electron capture—forms of radioactive decay in which a proton becomes a neutron—are not proton decay, because in these processes the proton interacts with other particles within the atom. Grand Unified Theories (GUTs) explicitly break the baryon number symmetry, allowing protons to decay via the Higgs particle, magnetic monopoles, or new X bosons with a half-life in the range 1031 to 1036 years. For comparison, the universe is roughly 1.4×1010 (14 billion) years old, which is at least twenty orders of magnitude lower. Although at first glance it may seem nearly impossible to explore such long lifetimes, it is sufficient to monitor 1034 protons per year (with efficiency = 1) to be sensitive to average lifetimes of 1034 years. About 1034 protons are contained in approximately 30 kton of water, slightly more than the fiducial volume of the most sensitive experiment currently in operation, Super-Kamiokande.
=== WPATH Standards of Care === The WPATH Standards of Care, most recently published in 2022, outlines a series of guidelines which should be met before a patient should be allowed gender-affirming hormone therapy:
=== 1. FC Lokomotive (since 2003–04) === In late 2003, the club was re-established by a group of fans as 1. FC Lokomotive Leipzig. The renewed side had to start in the lowest league, eleventh-tier 3. Kreisklasse, Staffel 2, in 2004–05. Even so, they continued to receive solidly enthusiastic fan support: their match against Eintracht Großdeuben's second team in the Leipzig Zentralstadion on 9 October 2004, broke the world record for lower-league attendance with 12,421 spectators. Thanks to a merger with SSV Torgau, the club could play in the seventh-tier Bezirksklasse Leipzig, Staffel 2, in 2005–06. Finishing this league as champions, the team qualified for the sixth-tier Bezirksliga. In 2006, 1. FC Lokomotive Leipzig also played a friendly match against FC United of Manchester (4–4) and qualified for the 2006–07 Landespokal by winning the Bezirkspokal. 1. FC Lokomotive Leipzig finished as champions of their group and were promoted to the fifth-tier Landesliga Sachsen Group for the 2007–08 season. The club finished second to Erzgebirge Aue and missed out on direct promotion to the NOFV-Oberliga Süd by two points in the 2007–08 season. It still had the chance to regain Oberliga status through a relegation play-off with Schönberg, winning the first leg 2–1 at Schönberg. In the return leg, in front of almost 10,000 spectators, the club lost 0–1 but still gained Oberliga promotion via the away goals rule. 1. FC Lokomotive Leipzig finished the Oberliga in third place in 2008–09, 12th in 2009–10, and eighth in 2010–11. 1.
Sources: en.wikipedia.org
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.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is 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.