The short version of ACTH(4-10) fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
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.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
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.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
=== Weaving pattern examination === The shroud is a large cloth woven in a 3/1 chevron herringbone twill, which according to the Scientific American requires a specific four-shaft treadle loom. Such floor looms appear in China around 1000 CE, with the four-shaft treadle loom only being introduced to Europe in the 13th century as indicated by Andrea Nicolotti and Susan Foulkes. In 2020, a test was conducted by weaver Antoinette Merete Olsen, who attempted to replicate the shroud's weave and size using the simpler warp-weighted loom of antiquity. Her results revealed that the Shroud of Turin must have been created on a treadle loom. History Today added that no manufactured three-in-one herringbone linen weave like the shroud has ever been discovered in ancient archaeological sites. The only other surviving parallel is a 14th century block-printed textile held at the Victoria and Albert Museum in London. Additionally, the shroud's linen yarn features a counter-clockwise Z-twist, a spinning technique typical of medieval Western Europe, contrasting with the clockwise S-twist which was traditional to Ancient Egypt and the Levant.
Commodore Tim Hare, former Director of Nuclear Policy at the British Ministry of Defence, has described "sub-strategic use" as offering the Government "an extra option in the escalatory process before it goes for an all-out strategic strike which would deliver unacceptable damage". However, this sub-strategic capacity has been criticized as potentially increasing the "acceptability" of using nuclear weapons. Combined with the trend in the reduction in the worldwide nuclear arsenal as of 2007 is the warhead miniaturization and modernization of the remaining strategic weapons that is presently occurring in all the declared nuclear weapon states, into more "usable" configurations. The Stockholm International Peace Research Institute suggests that this is creating a culture where use of these weapons is more acceptable and therefore is increasing the risk of war, as these modern weapons do not possess the same psychological deterrent value as the large Cold-War era, multi-megaton warheads. In many ways, this present change in the balance of terror can be seen as the complete embracement of the switch from the 1950s Eisenhower doctrine of "massive retaliation" to one of "flexible response", which has been growing in importance in the US nuclear war fighting plan/SIOP every decade since. For example, the United States adopted a policy in 1996 of allowing the targeting of its nuclear weapons at non-state actors ("terrorists") armed with weapons of mass destruction.
Allergen immunotherapy is useful for environmental allergies, allergies to insect bites, and asthma. Its benefit for food allergies is unclear and thus not recommended. Immunotherapy involves exposing people to larger and larger amounts of allergen in an effort to change the immune system's response. Meta-analyses have found that injections of allergens under the skin is effective in the treatment in allergic rhinitis in children and in asthma. The benefits may last for years after treatment is stopped. It is generally safe and effective for allergic rhinitis and conjunctivitis, allergic forms of asthma, and stinging insects. To a lesser extent, the evidence also supports the use of sublingual immunotherapy for rhinitis and asthma. For seasonal allergies the benefit is small. In this form the allergen is given under the tongue and people often prefer it to injections. Immunotherapy is not recommended as a stand-alone treatment for asthma.
Sources: en.wikipedia.org
Adoptive immunity acts in a host after their immunological components are withdrawn, their immunological activity is modified extracorporeally, and then reinfused into the same host. This process in its former part is analogous to adoption: a child is once adopted out from their home, grown up, and then returned to their home of birth. Transferred immunological components include immune cells such as T lymphocytes or tumour-infiltrating lymphocytes, NK cells, macrophages, or B cells. There seems to be some variation in usage of this term.
== In nuclear power reactors == In any operating nuclear reactor containing 238U, some plutonium-239 will accumulate in the nuclear fuel. Unlike reactors used to produce weapons-grade plutonium, commercial nuclear power reactors typically operate at a high burnup that allows a significant amount of plutonium to build up in irradiated reactor fuel. Plutonium-239 will be present both in the reactor core during operation and in spent nuclear fuel that has been removed from the reactor at the end of the fuel assembly's service life (typically several years). Spent nuclear fuel commonly contains about 0.8% plutonium-239. Plutonium-239 present in reactor fuel can absorb neutrons and fission just as uranium-235 can. Since plutonium-239 is constantly being created in the reactor core during operation, the use of plutonium-239 as nuclear fuel in power plants can occur without reprocessing of spent fuel; the plutonium-239 is fissioned in the same fuel rods in which it is produced. Fissioning of plutonium-239 provides more than one-third of the total energy produced in a typical commercial nuclear power plant. Reactor fuel would accumulate much more than 0.8% plutonium-239 during its service life if some plutonium-239 were not constantly being "burned off" by fissioning. A small percentage of plutonium-239 can be deliberately added to fresh nuclear fuel. Such fuel is called MOX (mixed oxide) fuel, as it contains a mixture of uranium dioxide (UO2) and plutonium dioxide (PuO2). The addition of plutonium-239 reduces the need to enrich the uranium in the fuel.
13 July Air pollution particles are shown to reduce insects' ability to find food and a mate, in experiments. This may be contributing to the dramatic fall in global insect populations, the scientists conclude. Scientists use CRISPR gene-editing to reduce the lignin content in poplar trees by as much as 50%, offering a potentially more sustainable method of fiber production. 14 July – The Indian Space Research Organisation (ISRO) successfully launches its Chandrayaan-3 spacecraft towards the Moon, aiming to become the fourth nation to achieve a soft landing on the lunar surface. 17 July – Astronomers of the Breakthrough Listen project report the development of a novel technique that can help distinguish between potential deliberate artificial alien signals and Earth-based radio interference via unique signatures from passing through ionized plasma of interstellar medium. 19 July – Astronomers report the discovery of a bizarre 'two-faced' star, with one side made up of hydrogen and the other consisting of helium. The object, designated ZTF J203349.8+322901.1, is a white dwarf located about 1,000 light years away. 18 July – The first example of naturally occurring graphene is reported, at a gold mine in South Africa. 19 July – Researchers report the discovery of self-healing of fatigue cracks in metals in vacuum.
Sources: en.wikipedia.org
=== Insomnia === Ramelteon is approved for the treatment of insomnia characterized by difficulty with sleep onset in adults. In regulatory clinical trials, it was found to significantly reduce latency to persistent sleep (LPS). A 2009 pooled analysis of four clinical trials found that ramelteon at a dose of 8 mg reduced sleep onset by 13 minutes (30% decrease) relative to placebo on the first and second nights of use. Subsequent meta-analyses of longer-duration use have found that ramelteon decreases subjective sleep latency by about 4 to 7 minutes. Meta-analyses are mixed on whether ramelteon increases total sleep time. Ramelteon also improves sleep quality (SMDTooltip standardized mean difference –0.074, 95% CITooltip confidence interval –0.13 to –0.02) and sleep efficiency. The clinical improvement in insomnia with ramelteon is small and of questionable benefit. Ramelteon is approved in the United States but was not approved in the European Union owing to concerns that it lacked effectiveness. The Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) noted that ramelteon had only been found to improve sleep onset and not other sleep outcomes, only one of three clinical trials actually found that it improved sleep onset, and that the improvement in sleep onset was too small to be clinically meaningful. The CHMP also noted that the long-term effectiveness of ramelteon had not been demonstrated.
=== Pruning === Blackcurrant fruit is borne primarily on one-year-old shoots. Newly planted bushes should be pruned severely, cutting all shoots back to two buds above ground level. This gives the plant a chance to get properly established before needing to put its energy into producing fruit. The general rule when pruning is to remove all weak shoots and those growing out sideways which may get weighed down when fruiting. The remaining branches should be thinned to remove old unproductive wood and to encourage new shoots. An established bush should not be allowed to become overcrowded and should have about one third of its main branches or stems removed each year. When harvesting by machine, plants with an upright growth habit are encouraged.
=== Very long-chain acyl-Coenzyme A dehydrogenase (VLCAD) deficiency === Very long-chain acyl-coenzyme A dehydrogenase deficiency (VLCAD deficiency) is a genetic disorder that affects the body's ability to break down certain fats. In the β-oxidation cycle, VLCAD's role involves the removal of two hydrogen atoms from the acyl-CoA molecule, forming a double bond and converting it into trans-2-enoyl-CoA. This crucial first step in the cycle is essential for the fatty acid to undergo further processing and energy production. When there is a deficiency in VLCAD, the body struggles to effectively break down long-chain fatty acids. This can lead to a buildup of these fats and a shortage of energy, particularly during periods of fasting or increased physical activity. Symptoms
Sources: en.wikipedia.org
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.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
Solid peptide is best kept frozen at about minus 20 degrees Celsius in a sealed container with desiccant. It should be allowed to reach room temperature before opening to prevent condensation. Repeated warming and cooling of the same vial is discouraged.