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.
Updated 2026-01-22. Numbers and descriptions here follow the published literature rather than marketing material.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
== Epidemiology == In the United States, the incidence of osteogenesis imperfecta is estimated to be one per 20,000 live births. An estimated 20,000 to 50,000 people are affected by OI in the United States. The most common types are I, II, III, and IV, while the rest are very rare. Type I is the most common and has been reported to be around three times more common than type II. The prevalence of types III and IV is less certain. In a 1989 study in Denmark, type I was found to comprise 71% of cases and type II 12% of cases, with other types comprising the other 17%. In a 2015 study in Sweden, type I was nearly six times more common than type III and nearly four times more common than type IV. Most people with OI receive it from a parent, but in many cases, it is a brand new (de novo or "sporadic") mutation in a family. Among a study of patients with survivable types of OI, OI type III is most often de novo (85%), followed by type IV (50%) and type I (34%). Some populations can have a higher incidence of OI than would be otherwise expected if they have a larger-than-average number of carriers of the recessive forms of the disease.
== Production == Unlike plutonium-238, plutonium-239, plutonium-240, plutonium-241, and plutonium-242, plutonium-244 is not produced in quantity by the nuclear fuel cycle, because further neutron capture on plutonium-242 produces plutonium-243 which has a short half-life (~5 hours) and quickly beta decays to americium-243 before having much opportunity to further capture neutrons in any but very high neutron flux environments. The global inventory of 244Pu is about 20 grams. Plutonium-244 is also a minor constituent of thermonuclear fallout, with a global 244Pu/239Pu fallout ratio of (5.7 ± 1.0) × 10−5.
==== Mushrooms ==== Conventional heat-drying methods for mushrooms shrink and tighten the fungal tissue, yielding a leathery product that is slow to reconstitute. Freeze drying mushrooms causes solid ice crystals to form and then sublimate within the mycelial tissue, leaving behind microscopic pores that create a light, airy, sponge-like texture that absorbs water rapidly. Studies of freeze-dried mushroom powder show higher solubility and better dispersibility than powders from heat-dried mushrooms.
=== Agents of spontaneous missense mutation === Environmental mutagens, such as tobacco smoke or UV radiation, may be a cause of spontaneous missense mutations. Tobacco smoke has been implicated in transversion mutations in the K-ras gene, with a meta-analysis of lung carcinomas showing 25 tumours containing a G to T mutation causing an amino acid change from glycine to cysteine, and 11 tumours with a G to T mutation causing an amino acid change from glycine to valine. Similarly, numerous studies have shown ultraviolet light induces missense mutations in the p53 gene, which when unregulated, reduces the cell's ability to recognize DNA damage and engage in apoptosis, leading to cell proliferation and potential skin carcinogenesis.
Sources: en.wikipedia.org
β particles emit lower energy as compared to α-emitters, but they have the advantage of having longer path length. However, due to their lower energy, more β particles are required to cause damage to tumor cells as compared to α-emitters. Some examples of β-emitters are 177Lu, 90Y, and 131I.
A study to compare the results of people taking a new treatment with the results of people taking the standard treatment (for example, which group has better survival rates or fewer side effects). In most cases, studies move into phase III only after a treatment seems to work in phases I and II. Phase III trials may include hundreds of people. (NCI) Expanded controlled and uncontrolled trials after preliminary evidence suggesting effectiveness of the drug has been obtained, and are intended to gather additional information to evaluate the overall benefit-risk relationship of the drug and provide and adequate basis for physician labeling. (NLM) Phase 3 studies are expanded controlled and uncontrolled trials. They are performed after preliminary evidence suggesting effectiveness of the drug has been obtained, and are intended to gather the additional information about effectiveness and safety that is needed to evaluate the overall benefit-risk relationship of the drug and to provide an adequate basis for physician labeling. Phase 3 studies usually include from several hundred to several thousand subjects. (21CFR312) Phase IV clinical trial
Soy protein products can be good substitutes for animal products because, unlike some other beans, soy offers a 'complete' protein profile. ... Soy protein products can replace animal-based foods—which also have complete proteins but tend to contain more fat, especially saturated fat—without requiring major adjustments elsewhere in the diet. Although soybeans have high protein content, soybeans also contain high levels of protease inhibitors, which can prevent digestion. Protease inhibitors are reduced by cooking soybeans, and are present in low levels in soy products such as tofu and soy milk. The Protein Digestibility Corrected Amino Acid Score (PDCAAS) of soy protein is the nutritional equivalent of meat, eggs, and casein for human growth and health. Soybean protein isolate has a biological value of 74, whole soybeans 96, soybean milk 91, and eggs 97.
=== 2025–present: Reunion with new line-up === On October 6, 2025, Lee and Lifeson announced that they were reforming Rush for a tour called Fifty Something which was scheduled from June to December 2026, with Anika Nilles on drums. Lee suggested that the tour would include up to two more musicians, including a backing keyboardist. Lee and Lifeson also stated that 35 songs would be performed on the tour, with the intention of varying their setlist at each show. Lee said that he and Lifeson began thinking more seriously about a reunion tour after they travelled to a health spa in Austria. Two years prior, Lifeson had undergone a surgery that left him with gastroparesis. Lee said when they returned home, both felt willing and able to consider a small number of tour dates in limited North American cities. What started as 12 dates quickly grew into 58 shows with more cities added. When asked in an interview with The Globe and Mail if the tour would include dates outside of North America, Lee said, "We're wrestling with extending the tour into 2027. I really don't know. We'll see how that all shakes down." On February 23, 2026, Rush announced that their first tour outside of North America is set to take place from January to April 2027, starting with their first live dates in South America in seventeen years, followed by the band's first tour in Europe in fourteen years.
On 17 September, the "All American" Division conducted its fourth and final combat jump of World War II. Fighting off German counterattacks, the division captured its objectives between Grave, and Nijmegen. The division failed to initially capture Nijmegen Bridge when the opportunity presented itself early in the battle. When the British XXX Corps arrived in Nijmegen, six hours ahead of schedule, they found themselves having to fight to take a bridge that should have already been in Allied hands. In the afternoon of Wednesday 20 September 1944, the 82nd Airborne Division successfully conducted an opposed assault crossing of the Waal river. War correspondent Bill Downs, who witnessed the assault, described it as "a single, isolated battle that ranks in magnificence and courage with Guam, Tarawa, Omaha Beach. A story that should be told to the blowing of bugles and the beating of drums for the men whose bravery made the capture of this crossing over the Waal possible." The Market Garden salient was held in a defensive operation for several weeks until the 82nd was relieved by Canadian troops, and sent into reserve in France. During the operation, 19-year-old Private John R. Towle of the 504th PIR was posthumously awarded the 82nd Airborne Division's second Medal of Honor of World War II.
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.