ACTH fragment raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-01-07. Anything still debated is marked as such rather than presented as settled.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
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.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
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.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
If PCI cannot be performed within 90 to 120 minutes in STEMI then fibrinolysis, preferably within 30 minutes of arrival to hospital, is recommended. If a person has had symptoms for 12 to 24 hours evidence for effectiveness of thrombolysis is less and if they have had symptoms for more than 24 hours it is not recommended. Thrombolysis involves the administration of medication that activates the enzymes that normally dissolve blood clots. These medications include tissue plasminogen activator, reteplase, streptokinase, and tenecteplase. Thrombolysis is not recommended in a number of situations, particularly when associated with a high risk of bleeding or the potential for problematic bleeding, such as active bleeding, past strokes or bleeds into the brain, or severe hypertension. Situations in which thrombolysis may be considered, but with caution, include recent surgery, use of anticoagulants, pregnancy, and proclivity to bleeding. Major risks of thrombolysis are major bleeding and intracranial bleeding. Pre-hospital thrombolysis reduces time to thrombolytic treatment, based on studies conducted in higher income countries; however, it is unclear whether this has an impact on mortality rates.
The band posted a tribute to him on their website in September 2022. In 2023, Johnston, McDonald, and Simmons (as the Doobie Brothers) were nominated for induction into the Songwriters Hall of Fame. In addition, a continuation of their 50th Anniversary tour was planned for the year. The Doobies started their 2023 touring schedule in Australia and Japan in April before making their way to Hawaii and then returning to the continental U.S. in May. Three days before they were set to perform in Hollywood, Florida, the band released a statement that Tom Johnston would be undergoing surgery following severe back pain and would not be able to join the band on the upcoming leg of the 50th Anniversary Tour. Simmons, McDonald, and McFee continued the 2023 touring schedule in Johnston's absence. Lead vocals normally performed by Johnston were shared between Simmons, McDonald, and bassist John Cowan. In June 2023, Simmons said in an interview that the band will be releasing new music the next year with McDonald. The band opened for the Eagles on the latter's The Long Goodbye Tour in November 2023, replacing Steely Dan due to Donald Fagen's health issues. On November 17, 2023, the Doobie Brothers released a new single entitled "Lahaina" to benefit the families and individuals affected by the 2023 Hawaii wildfires. The song, produced by John Shanks, features Mick Fleetwood on drums, Jake Shimabukuro on ukulele, and Henry Kapono on vocals. In 2024 a fully healed Tom Johnston rejoined the Doobies, who continued on with their 50th Anniversary tour.
7-CPP antagonist SRIF-A CyCam cyclo(7-Ahep-Phe-Trp-Lys-Thr(Bzl)) cyclo(7-aminoheptanoylphenylalanyl-tryptophyl-lysyl-benzylthreonyl) cyclo-(7-aminoheptanoyl-Phe-D-Trp-Lys-Thr(Bzl)) Cyclosomatostatin may have the possibility of treating complications of acute hemorrhage. Hepatic insulin sensitizing substance (HISS), a hormone, will be secreted by the liver which stimulates skeletal muscle glucose uptake when responding to insulin. This action makes up around 56% of total insulin action. Hemorrhage was shown to cause insulin resistance by this type of HISS-dependent insulin resistance (HDIR). Two animal studies shows that cyclosomatostatin can help prevent HDIR without correcting the hyperglycemic condition in the situation of hemorrhage and exogenous somatostatin infusion. Cyclosomatostatin may be related to other indications, including the potential of blocking the suppression of gastric emptying triggered by corticotropin-releasing hormone (CRH), the key regulator of the hypothalamic-pituitary-adrenal axis released to alter the body response caused by stress. Furthermore, cyclosomatostatin, even if used alone, may modulate neurotransmitter levels. It increases acetylcholine (ACh) release by reversing the inhibitory effect of a substance, DHP agonist Bay K 8844, to L-type voltage-sensitive Ca2+ calcium channel.
Partly to aid the Apollo missions, the Surveyor program was conducted by NASA, with five successful soft landings out of seven attempts from 1966 to 1968. The Lunar Orbiter program had five successes out of five attempts in 1966–1967. In late 1966, Luna 13 became the third spacecraft to make a soft-landing on the Moon, with the American Surveyor 1 having now taken second. Luna 13 made use of inflatable air-bags to soften it's landing. Surveyor 1 was a 995 kg lander, notably larger than the 112 kg Luna 13 E-6M lander. Surveyor 1 was equipped with a Doppler velocity sensing system that fed information into the spacecraft computer to implement a controllable descent to the surface. Each of the three landing pads also carried aircraft-type shock absorbers and strain gauges to provide data on landing characteristics, important for future Apollo missions. Surveyor 3, which successfully touched down on the Moon April 20, 1967, carried a 'surface sampler' which facilitated tests of the Lunar soil. Based on these experiments, scientists concluded that lunar soil had a consistency similar to wet sand, with a bearing strength of about 10 pounds per square inch (0.7 kilograms per square centimeter, or 98 kilopascals), which was concluded to be solid enough to support an Apollo Lunar Module. The Surveyor 3 lander would be later visited by Apollo 12 astronauts. On Nov. 17, 1967, before mission termination, Surveyor 6 fired its thrusters for 2.5 seconds, becoming the first spacecraft launched from the lunar surface.
BALB/c is an albino laboratory-bred strain from which a number of common substrains are derived. With over 200 generations bred since 1920, BALB/c mice are distributed globally and are among the most widely used inbred strains used in animal experimentation. BALB/c are noted for displaying high levels of anxiety and for being relatively resistant to diet-induced atherosclerosis, making them a useful model for cardiovascular research. Male BALB/c mice are aggressive and will fight other males if housed together. However, the BALB/Lac substrain is much more docile. Most BALB/c mice substrains have a long reproductive life-span. There are noted differences between different BALB/c substrains, though these are thought to be due to mutation rather than genetic contamination. The BALB/cWt is unusual in that 3% of progeny display true hermaphroditism.
Sources: en.wikipedia.org
A cement is a binder used for construction that sets, hardens, and adheres to other materials to bind them together. Cement is seldom used on its own, but rather to bind sand and gravel (aggregate) together. Cement mixed with fine aggregate produces mortar for masonry, or with sand and gravel, produces concrete. Concrete is the most widely used material in existence and is behind only water as the planet's most-consumed resource. Cements used in construction are usually inorganic, often lime- or calcium silicate-based, and are either hydraulic or less commonly non-hydraulic, depending on the ability of the cement to set in the presence of water (see hydraulic and non-hydraulic lime plaster). Hydraulic cements such as Portland cement set and become adhesive through a chemical reaction between the dry ingredients and water. The chemical reaction results in mineral hydrates that are not very water-soluble. This allows setting in wet conditions or under water and further protects the hardened material from chemical attack. The chemical process for hydraulic cement was found by ancient Romans who used volcanic ash (pozzolana) with added lime (calcium oxide). Non-hydraulic cement does not set in wet conditions or under water. Rather, it sets as it dries and reacts with carbon dioxide in the air. It is resistant to attack by chemicals after setting. World production of cement is about 4.4 billion tonnes per year (2021, estimation), of which about half is made in China, followed by India and Vietnam.
An almost immediate move to challenge Gaddis' framework came from Melvyn P. Leffler, who "demonstrated that it was not so much the actions of the Kremlin as it was fears about socioeconomic dislocation, revolutionary nationalism, British weakness, and Eurasian vacuums of power that triggered US initiatives to mold an international system to comport with its concept of security". That provoked "strong rebuttals" from Gaddis and his followers, but Leffler deemed their objections inaccurate and unsubstantiated. However, Leffler himself still falls within the overall post-revisionist camp. Out of the "post-revisionist" literature emerged a new area of inquiry that was more sensitive to nuance and interested less in the question of who started the conflict than in offering insight into United States and Soviet actions and perspectives. From that perspective, the Cold War was not so much the responsibility of either side, but rather the result of predictable tensions between two world powers that had been suspicious of one another for nearly a century. For example, Ernest May wrote in a 1984 essay:
Han Chinese can be divided into subgroups, based on the variety of Chinese that they speak. Waves of migration have occurred throughout China's long history and vast geographical expanse, engendering the emergence of Han Chinese subgroups found throughout the regions of modern China today, with distinct regional features.
=== Physical === Neptunium is a hard, silvery, ductile, radioactive actinide metal (all actinides are metals). In the periodic table, it is located to the right of the actinide uranium, to the left of the actinide plutonium and below the lanthanide promethium. Neptunium is a hard metal, having a bulk modulus of 118 GPa, comparable to that of manganese. Neptunium metal is similar to uranium in terms of physical workability. When exposed to air at normal temperatures, it forms a thin oxide layer. This reaction proceeds more rapidly as the temperature increases. Neptunium melts at 639 ± 3 °C: this low melting point, a property the metal shares with the neighboring element plutonium (which has melting point 639.4 °C), is due to the hybridization of the 5f and 6d orbitals and the formation of directional bonds in the metal. The boiling point of neptunium is not empirically known and the usually given value of 4174 °C is extrapolated from the vapor pressure of the element. If accurate, this would give neptunium the largest liquid range of any element (3535 K passes between its melting and boiling points). Neptunium is found in at least three allotropes. Some claims of a fourth allotrope have been made, but they are so far not proven. This multiplicity of allotropes is common among the actinides. The crystal structures of neptunium, protactinium, uranium, and plutonium do not have clear analogs among the lanthanides and are more similar to those of the 3d transition metals.
Sources: en.wikipedia.org
However, the commission concluded that an attack on Russian peacekeepers was not "a sufficient condition" to be used for self-defence by Russia and "the fact of the Georgian attack on the Russian peacekeepers’ basis could not be definitely confirmed by the mission." The commission said that Russian peacekeepers had the right to immediate, necessary and proportionate response in case of direct attack on them. However, "doubts remain whether the Russian peacekeepers were attacked in the first place," and the mission "was unable to establish whether, at the time of the alleged attacks on Russian peacekeepers’ bases, the peacekeepers had lost their protection owing to their participation in the hostilities." The commission concluded that "the expulsion of the Georgian forces from South Ossetia, and the defence of South Ossetia as a whole was not a legitimate objective", and "according to international law, the Russian military action taken as a whole was therefore neither necessary nor proportionate to protect Russian peacekeepers in South Ossetia." The commission concluded that Russia did not have the right to justify its actions as "a mere reinforcement and fulfilment of its peacekeeping mission." The commission concluded that the South Ossetian separatists "could not validly invite Russia to support them" militarily and Russian military action could not be justified as intervention in a civil war.
== New National Hospital Project == The New National Hospital project (Icelandic: Nýr Landspítali, NLSH) is a large-scale public infrastructure project aimed at replacing the existing facilities of Landspítali. The hospital currently operates across multiple buildings in several locations in the greater Reykjavík area, many of which are said to longer meet modern healthcare requirements.
=== Metallocenium ions === The most famous example is ferrocenium, [Fe(C5H5)2]+, the blue iron(III) complex derived from oxidation of orange iron(II) ferrocene. The lithocene anion, [Li(C5H5)2]–, is the best-documented example of a metallocene anion; otherwise such ions are little known.
Sources: en.wikipedia.org
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.