This is a working overview of ACTH fragment, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-06-04 and is reviewed periodically as new material appears.
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.
== Educational research == Industrialist John D. Rockefeller was instrumental in establishing the General Education Board (GEB), of which he maintained expenditure control. The GEB adopted his beliefs, promoting vocational education across a 5-decade span. The Rockefeller Foundation, like the Carnegie Corporation, supported early educational broadcasting and the participation of commercial radio, vis-à-vis education-only stations. It explored radio's educational effectivity in both classroom and adult settings and explored methods to share those results. Via GEB dispersals the Rockefeller Foundation provided financial support for Wisconsin's and Ohio's early School of the Air experiments, among other educational project recipients. The Foundation's interest in broadcasting as a tool subsequently led to communication research, e.g. how radio "could be used for public edification, control, and pacification", promoting university-level social science studies. The social engineering success of these early social scientists led to social sciences becoming institutionalized with Rockefeller Foundation's influence leading the transformation.
This glossary of cellular and molecular biology is a list of definitions of terms and concepts commonly used in the study of cell biology, molecular biology, and related disciplines, including molecular genetics, biochemistry, and microbiology. It is split across two articles:
For example in the United States, bills on cosmetics, food packaging, and textiles meant to regulate PFAS failed to pass through Congress in 2022. In 2026, the UK increased testing for PFAS as part of a national plan to tackle the substances, which have prompted environmental and health concerns. The government says that by 2029 it wants to align more closely with regulations issued by the EU, which is looking to prohibit all non-essential uses.
Commander-in-Chief of the Ukrainian Armed Forces Oleksandr Syrskyi confirmed that Ukrainian forces had retreated from the villages of Berdychi, Semenivka, and Novomykhailivka in Donetsk Oblast. He also said that Ukrainian forces had regained control of Nestryha Island in the Dnipro River delta in Kherson Oblast. The ISW assessed that Ukrainian soldiers suffered a "one-to-three manpower disadvantage" northwest of Avdiivka. Russia claimed to have shot down 17 drones over Belgorod, Kursk, Kaluga and Bryansk Oblasts. Russian milbloggers claimed that Ukraine conducted an unsuccessful ATACMS strike on Russian air defense units at Cape Tarkhankut, Crimea. Ukraine announced that it would partially suspend its adherence to the European Convention on Human Rights to be able to fully apply martial law on its territory.
Sources: en.wikipedia.org
Parenchyma () is the bulk of functional substance in an animal organ such as the brain or lungs, or a structure such as a tumour. In zoology, it is the tissue that fills the interior of flatworms. In botany, it is some layers in the cross-section of the leaf.
Extremely strong: Histamine H1 receptor Strong: α1-adrenergic receptor, 5-HT2A and muscarinic acetylcholine receptors Moderate: 5-HT2C and 5-HT1A receptors Weak: α2-adrenergic and D2 receptors Based on its IC50Tooltip half-maximal inhibitory concentration values for monoamine reuptake inhibition, doxepin is relatively selective for the inhibition of norepinephrine reuptake, with a much weaker effect on the serotonin transporter. Although there is a significant effect that takes place at one of the specific serotonergic binding sites, the 5-HT2A serotonin receptor subtype. There is negligible influence on dopamine reuptake. The major metabolite of doxepin, nordoxepin (desmethyldoxepin), is pharmacologically active similarly, but relative to doxepin, is much more selective as a norepinephrine reuptake inhibitor. In general, the demethylated variants of tertiary amine TCAs like Nortriptyline, Desipramine and nordoxepin are much more potent inhibitors of norepinephrine reuptake, less potent inhibitors of serotonin reuptake, and less potent in their antiadrenergic, antihistamine, and anticholinergic activities. Antidepressant doses of doxepin are defined as 25 to 300 mg/day, although are typically above 75 mg/day. Antihistamine doses, including for dermatological uses and as a sedative/hypnotic for insomnia, are considered to be 3 to 25 mg, although higher doses between 25 and 50 mg and in some cases even up to 150 mg have been used to treat insomnia. At low doses, below 25 mg, doxepin is a pure antihistamine and has more of a sedative effect.
In addition, Marcos limited his position on the matter through oral statements and avoided issuing an executive order formalizing his stance. There were also unconfirmed reports, including by former Senator Antonio Trillanes, stating that ICC members had already entered the Philippines and were already secretly conducting the investigation. A House probe initiated in April 2024 by Romualdez into a "status quo" agreement in the South China Sea Duterte made during his presidency with Chinese president Xi Jinping was also seen as a "political payback" to Duterte's verbal attacks on Marcos and diminish Duterte's political influence ahead of the 2025 midterm elections. Amidst growing isolation, Duterte found allies who were previously loyal to Marcos. Among them were Marcos' longtime lawyer, Vic Rodriguez, who served as executive secretary in Marcos' first 79 days before resigning; and Marcos' sister, Senator Imee Marcos. On March 11, 2025, Duterte was arrested upon his arrival at Ninoy Aquino International Airport by the Filipino police, which enforced an arrest warrant issued by the International Criminal Court.
The cover version by Selena Gomez was released on 22 July 2009 as part of the Radio Disney iTunes Pass, serving as a promotional single for the soundtrack of the Disney Channel television series Wizards of Waverly Place. It debuted and peaked at no. 61 on the U.S. Billboard Hot 100 chart with 42,000 downloads. It also peaked at No. 80 on the Canadian Hot 100 chart, No. 5 on the Norwegian Singles Chart and at No. 90 on the UK Singles Chart. It has sold 563,000 copies in the United States. The song was featured in the television film Wizards of Waverly Place: The Movie. The music video premiered on the Disney Channel on 24 July 2009, and was directed by Roman Perez.
=== Generic names === Progesterone is the generic name of the drug in English and its INNTooltip INN, USANTooltip United States Adopted Name, USPTooltip United States Pharmacopeia, BANTooltip British Approved Name, DCITTooltip Denominazione Comune Italiana, and JANTooltip Japanese Accepted Name, while progestérone is its name in French and its DCFTooltip Dénomination Commune Française. It is also referred to as progesteronum in Latin, progesterona in Spanish and Portuguese, and progesteron in German.
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。