ACTH fragment raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-05-13. 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. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
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.
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
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.
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.
=== Waste disposal === The long half-life of technetium-99 and its potential to form anionic species creates a major concern for long-term disposal of radioactive waste. Many of the processes designed to remove fission products in reprocessing plants aim at cationic species such as caesium (e.g., caesium-137) and strontium (e.g., strontium-90). Hence the pertechnetate escapes through those processes. Current disposal options favor burial in continental, geologically stable rock. The primary danger with such practice is the likelihood that the waste will contact water, which could leach radioactive contamination into the environment. The anionic pertechnetate and iodide tend not to adsorb into the surfaces of minerals, and are likely to be washed away. By comparison plutonium, uranium, and caesium tend to bind to soil particles. Technetium could be immobilized by some environments, such as microbial activity in lake bottom sediments, and the environmental chemistry of technetium is an area of active research. An alternative disposal method, transmutation, has been demonstrated at CERN for technetium-99. In this process, the technetium (technetium-99 as a metal target) is bombarded with neutrons to form the short-lived technetium-100 (half-life = 16 seconds) which decays by beta decay to stable ruthenium-100.
== Adverse effects == Adverse effects in studies that were significantly more common under ertugliflozin than under placebo included mycosis of the genitals in both men and women, vaginal itch, increased urination, thirst, hypoglycaemia (low blood sugar), and weight loss under the higher dosing scheme. A rare but life-threatening side effect of gliflozins is ketoacidosis; it occurred in three patients (0.1%) in ertugliflozin studies. To lessen the risk of developing ketoacidosis (a serious condition in which the body produces high levels of blood acids called ketones) after surgery, the FDA has approved changes to the prescribing information for SGLT2 inhibitor diabetes medicines to recommend they be stopped temporarily before scheduled surgery. Symptoms of ketoacidosis include nausea, vomiting, abdominal pain, tiredness, and trouble breathing.
== Statements by Russian analysts == In August 2008, Pavel Felgenhauer, a Moscow-based analyst of military affairs, wrote in Novaya Gazeta that the Russian plan was for the Ossetians to deliberately provoke the Georgians so that "any response, harsh or soft, would be used as an occasion for the attack". He noted that Russia's invasion of Georgia had been planned in advance, with the final political decision to start the war apparently having been made back in April. The war was planned to start no later than the second half of August, because in the following months the weather would deteriorate. The goal of the war was to expel all Georgians from Abkhazia and South Ossetia, to free Tbilisi from Saakashvili, and to force NATO and Americans to abandon the Caucasus region. If the Georgians had not responded to South Ossetian attacks, then Abkhaz separatists would have started the operation to reclaim the Kodori Gorge. But Saakashvili succeeded in destroying the Ossetian militia and Moscow had no other option rather than to confront Georgia itself openly. Felgenhauer also made similar arguments in another English-language article. He wrote that "The invasion was inevitable, no matter what the Georgians did." Earlier, on 7 August, Felgenhauer claimed that although South Ossetian separatists wanted Russia to intervene, "apparently not everyone in Moscow" was "ready to plunge headlong into war." It was Felgenhauer who predicted in June 2008 that Vladimir Putin would start a war against Georgia in Abkhazia and South Ossetia supposedly in late August 2008.
=== In drug discovery and biomedical research === The ability to grow up functional adult tissues indefinitely in culture through Directed differentiation creates new opportunities for drug research. Researchers are able to grow up differentiated cell lines and then test new drugs on each cell type to examine possible interactions in vitro before performing in vivo studies. This is critical in the development of drugs for use in veterinary research because of the possibilities of species-specific interactions. The hope is that having these cell lines available for research use will reduce the need for research animals used because effects on human tissue in vitro will provide insight not normally known before the animal testing phase.
Sources: en.wikipedia.org
Starring a principal cast of Josh Hartnett, Bruce Willis, Lucy Liu, Stanley Tucci, and Ben Kingsley, the film garnered mixed reception. David Mattin of BBC wrote: "Kingsley and Freeman shine individually, but their inevitable, climactic clash of heads lacks force. Like its leading man [Hartnett], this movie presents a charming façade with nothing much underneath." Next, Freeman portrayed himself in the low-budget comedy 10 Items or Less opposite Paz Vega. Two weeks after its theatrical release, 10 Items or Less was made available for download from ClickStar, a film distribution company that Freeman co-founded that year. In 2007, Freeman reprised his role as God in Evan Almighty, a sequel to 2003's Bruce Almighty, with Steve Carell. Evan Almighty was a box-office failure and negatively received; The Guardian critic wrote: "A cast full of people who have been frequently funny elsewhere flounder in this deluge of sentimentality and CGI. Avoid like the Ten Plagues." The drama Feast of Love was Freeman's second release of 2007. It is based on the 2000 novel The Feast of Love by Charles Baxter, about a group of friends living in suburban Oregon who come into contact with a free spirit who changes their outlook on life; Peter Bradshaw of The Guardian sarcastically remarked that it was great to see Freeman in a challenging role. Freeman had a supporting part in Gone Baby Gone (2007), a mystery thriller that was also Ben Affleck's directorial debut. Adapted from the 1998 novel of the same name by Dennis Lehane, Freeman plays Captain Jack Doyle of the Boston Police Department.
Birch wood is fine-grained and pale in colour, often with an attractive satin-like sheen. Ripple figuring may occur, increasing the value of the timber for veneer and furniture-making. The highly decorative Masur (or Karelian) birch, from Betula verrucosa var. carelica, has ripple textures combined with attractive dark streaks and lines. Birch plywood is made from laminations of birch veneer. It is light but strong, and has many other good properties. It is among the strongest and dimensionally most stable plywoods, although it is unsuitable for exterior use. Birch plywood is used to make longboards (skateboard), giving it a strong yet flexible ride. It is also used (often in very thin grades with many laminations) for making model aircraft. Birch wood is often used in the manufacture of popsicle sticks due to its durability, smoothness and neutral flavour. Extracts of birch are used for flavoring and leather oil, and in cosmetics such as soap and shampoo. In the past, commercial oil of wintergreen (methyl salicylate) was made from the sweet birch (Betula lenta). Birch-tar or Russian oil extracted from birch bark is thermoplastic and waterproof; it was used as a glue on, for example, arrows, and also for medicinal purposes. Fragrant twigs of wintergreen group birches are used in saunas. Birch is also associated with the feast of Pentecost in Central and Eastern Europe and Siberia, where its branches are used as decoration for churches and homes on this day.
=== NAADP inhibitors === Back in 2009, a selective cell-permeant NAADP antagonist, trans-Ned-19 was discovered which blocks Ca2+ signals and downstream Ca2+-dependent processes such as differentiation. Prior to that, only high concentrations of blockers of L-type Ca2+ channels (e.g. diltiazem, dihydropyridines) could be used (with obvious concerns over non-NAADP effects). A minor modification of Ned-19 produced another, more soluble antagonist, Ned-K. Although not true antagonism, the NAADP 'receptor' can self-inactivate when bound to non-releasing concentrations of NAADP itself. Such inactivating pre-pulses of NAADP were the first strategy for implicating NAADP in subsequent physiological pathways.
While osteoarthritis is a degenerative joint disease that may cause gross cartilage loss and morphological damage to other joint tissues, more subtle biochemical changes occur in the earliest stages of osteoarthritis progression. The water content of healthy cartilage is finely balanced by compressive force driving water out and hydrostatic and osmotic pressure drawing water in. Collagen fibres exert the compressive force, whereas the Gibbs–Donnan effect and cartilage proteoglycans create osmotic pressure which tends to draw water in. However, during the onset of osteoarthritis, the collagen matrix becomes more disorganized, and there is a decrease in proteoglycan content within cartilage. The breakdown of collagen fibers results in a net increase in water content. This increase occurs because whilst there is an overall loss of proteoglycans (and thus a decreased osmotic pull), it is outweighed by a loss of collagen. Other structures within the joint can also be affected. The ligaments within the joint become thickened and fibrotic, and the menisci can become damaged and wear away. Menisci can be completely absent by the time a person undergoes a joint replacement. New bone outgrowths, called "spurs" or osteophytes, can form on the margins of the joints, possibly in an attempt to improve the congruence of the articular cartilage surfaces in the absence of the menisci. The subchondral bone volume increases and becomes less mineralized (hypo mineralization). All these changes can cause problems functioning.
== National variants == Similar meat and pastry recipes include the Czech klobásník, the Belgian worstenbroodje, the Dutch saucijzenbroodje, the German Münsterländer Wurstbrötchen and sausage bread in the United States. Hong Kong has developed its own style of sausage roll. Instead of having sausage meat wrapped in puff pastry like the traditional Western style, the Hong Kong style "sausage bun" (Chinese: 腸仔包) consists of a sausage wrapped inside a soft milk bread style bun.
Sources: en.wikipedia.org
Jindřich "Henry" Kopeček (born January 27, 1940) is a Czech-American chemist. He is a professor of pharmaceutical chemistry and a professor of biomedical engineering at the University of Utah in Salt Lake City, Utah. Kopeček is also an honorary professor at Sichuan University in Chengdu, China. His research focuses on biorecognition of macromolecules, bioconjugate chemistry, drug delivery systems, self-assembled biomaterials, and drug-free macromolecular therapeutics. Kopeček is regarded as one of the pioneers in development of biomedicinal polymers such as hydrogel implants and design of new polymer-drug conjugates. He was a key figure in a group which created the first clinically tested polymeric cancerostatics (PK1 and PK2). Hydrogels from his laboratory have been in clinical use. He was elected a member of the U.S. National Academy of Engineering in 2011 for contributions to the design of hydrogel biomaterials and polymeric drug delivery systems. In 2018, he was elected Fellow of the National Academy of Inventors. As of July 15, 2021, Kopeček has been cited over 35,000 times, with an h-index of 100, and I-10 index of 408.
Radiation therapy is usually reserved for people who have tumours remaining after surgery. These people often also receive medication to lower GH levels. Radiation therapy is given in divided doses over four to six weeks. This treatment lowers GH levels by about 50 percent over 2 to 5 years. People monitored for more than 5 years show significant further improvement. Radiation therapy causes a gradual loss of production of other pituitary hormones with time. Loss of vision and brain injury, which have been reported, are very rare complications of radiation treatments.
Dual-flow, also known as dual, countercurrent chromatography occurs when both phases are flowing in opposite directions inside the column. Instruments are available for dual-flow operation for both Hydrodynamic and hydrostatic CCC. Dual-flow countercurrent chromatography was first described by Yoichiro Ito in 1985 for foam CCC where gas-liquid separations were performed. Liquid–liquid separations soon followed. The countercurrent chromatography instrument must be modified so that both ends of the column have both inlet and outlet capabilities. This mode may accommodate continuous or sequential separations with the sample being introduced in the middle of the column or between two bobbins in a hydrodynamic instrument. A technique called intermittent countercurrent extraction (ICcE) is a quasi-continuous method where the flow of the phases is alternated "intermittently" between normal and reversed-phase elution so that the stationary phase also alternates.
2 Bh + 3 O2 + 2 HCl → 2 BhO3Cl + H2 The longer-lived heavy isotopes of bohrium, produced as the daughters of heavier elements, offer advantages for future radiochemical experiments. Although the heavy isotope 274Bh requires a rare and highly radioactive berkelium target for its production, the isotopes 272Bh, 271Bh, and 270Bh can be readily produced as daughters of more easily produced moscovium and nihonium isotopes.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受，但会加快降解风险。