A practical reference on ACTH fragment: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-06-02. Anything still debated is marked as such rather than presented as settled.
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。
从分子层面看,Semax 是线性七肽,没有二硫键、糖基或脂链修饰,N 端为游离氨基,C 端为游离羧基。分子含组氨酸与谷氨酸侧链,因此在水和甲醇等极性溶剂中溶解良好,在非极性溶剂中溶解有限。计算分子量约为 814 Da,与其质子化离子的质荷比吻合,可用于质谱确认。
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.
| Property | Value | Notes |
|---|---|---|
| 分子式 | C37H51N9O10S | 游离碱形式 |
| 等电点 | 约 6.5 | 估算值,随缓冲体系变化 |
| 主要降解途径 | 水解与氧化 | 侧链氧化最为常见 |
| 溶液储存 | 2 至 8 摄氏度避光 | 避免反复冻融 |
| 常规分析手段 | 反相色谱与质谱联用 | 氨基酸分析辅助核对 |
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。
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。
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.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
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.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
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.
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.
The IDF said that it killed a senior commander of the elite Redwan Force unit along with a deputy and another fighter in Nabatieh which was confirmed by Hezbollah the next day. A total of seven Hezbollah members were announced dead from the attacks. In response to the launch of a UAV toward the Lower Galilee from Lebanese territory on 19 February, Israeli jets targeted Hezbollah militants in Marwahin, two weapons storage facilities near the city of Sidon, and Hezbollah infrastructure in the Meiss El Jabal and al-Adisa areas of Lebanon. On 21 February, an Israeli airstrike on a residential area of Damascus near a fortified compound used by Syrian security forces killed two civilians. On the same day, an Israeli airstrike on the village of Majdal Zoun killed two more civilians, a mother and her child. In addition, Israeli forces struck a Hezbollah observation post in Ramyeh and shelled an area near Aitaroun with artillery to "remove threats." Later on Israeli jets attacked an observation post in Khaim, a military post in Zibqin—from which a missile was fired at Shlomi—and other Hezbollah infrastructure. On 22 February, after a projectile from Lebanon hit a home in the border town of Yuval, an Israeli drone struck an apartment building in Kfar Remen, killing at least two Hezbollah fighters and wounding three others. The next day, on 23 February, an Israeli strike on a Hezbollah-linked clinic in Blida killed two civilian paramedics and one Hezbollah fighter and injured an unknown number of people.
ALK-negative ALCL tumor cells show products made by chimeric genes: DUSP22-IRF4 (many of which are fused at particular site and termed DUSP22-FRA7H) in 30% of the cases; TP63-TBL1XR1 in 8% of cases; and NFKB2-ROS1, NCOR2-ROS1, NFKB2-TYK2, or PABPC4-TYK2 in rare cases. They also show mutations in the JAK1 and/or STAT3 genes in 18% of cases; the MSC gene in 15% of cases, and the NOTCH1 gene in 15% of cases. About 24% of cases have a truncated ERBB4 gene. DUSP22 gene rearrangements have been associated with favorable outcomes in ALK-negative ALCL while TP63 gene arrangements are often associated with a poorer prognosis in various cancers. ALK-negative ALCL cells overexpress overactive STAT3 in 47% of cases and JAK1 in many cases. Many of these gene abnormalities appear to contribute to the development of ALK-negative ALCL.
The earliest known regulators of gene expression were proteins known as repressors and activators – regulators with specific short binding sites within enhancer regions near the genes to be regulated. Later studies have shown that RNAs also regulate genes. There are several kinds of RNA-dependent processes in eukaryotes regulating the expression of genes at various points, such as RNA interference repressing genes post-transcriptionally, long non-coding RNAs shutting down blocks of chromatin epigenetically, and enhancer RNAs inducing increased gene expression. Bacteria and archaea have also been shown to use regulatory RNA systems such as bacterial small RNAs and CRISPR. Fire and Mello were awarded the 2006 Nobel Prize in Physiology or Medicine for discovering microRNAs (miRNAs), specific short RNA molecules that can base-pair with mRNAs.
Thorium-232 (232Th) is the main naturally occurring isotope of thorium, with a relative abundance of approximately 99.98%. It has a half-life of 14.0 billion years, which makes it the longest-lived isotope of thorium. It decays by alpha decay to radium-228; its decay chain terminates at stable lead-208. Thorium-232 is a fertile material; it can capture a neutron to form thorium-233, which subsequently undergoes two successive beta decays to uranium-233, which is fissile. As such, it has been used in the thorium fuel cycle in nuclear reactors; various prototype thorium-fueled reactors have been designed. However, as of 2024, thorium fuel has not been widely adopted for commercial-scale nuclear power. In 2025, China reported thorium-to-uranium conversion in an experimental molten-salt reactor.
Sources: en.wikipedia.org
Parliament sits at the Houses of Parliament, Cape Town, even though the seat of government is in Pretoria. This dates back to the foundation of the Union, when there was disagreement among the four provinces as to which city would be the national capital. As a compromise, Cape Town was designated the legislative capital, Bloemfontein the judicial capital, and Pretoria the administrative capital. The African National Congress (ANC) government has proposed moving Parliament to Pretoria, arguing that the present arrangement is cumbersome as ministers, civil servants and diplomats must move back and forth when Parliament is in session. However, many Capetonians have spoken out against such a move, accusing the ANC of trying to centralise power. Under the Constitution, there is provision for Parliament to sit elsewhere than Cape Town on grounds of public interest, security or convenience and Parliament is permitted to provide in its rules and orders for sittings outside Cape Town. Rule 24 of the National Assembly Rules accordingly allows the Speaker to direct that the House will sit at 'a place other than the Houses of Parliament in Cape Town' after consulting the Leader of the House and the Chief Whip of each party represented in the House. Rule 23 of the rules of the National Council of Provinces allows the council to pass a resolution providing for it to sit elsewhere. In 2018, the Government of South Africa formed a project steering committee to conduct a feasibility study into moving parliament to Pretoria and to identify potential sites for a new parliament building.
=== Farnesoid X-receptor agonist === A new novel treatment option is the farnesoid X receptor is responsible for regulating bile acid homeostasis. An agonist of this nuclear hormone receptor is seen as a possible treatment as it can downregulate bile acid synthesis and reabsorption. Further the farnesoid X receptor is partly responsible for lipid and glucose homeostasis, as well as pathogen recognition. An agonist for the farnesoid X receptor can therefore lead to an anti-cholestatic environment to minimize the effect of toxic bile acids on the liver. A candidate agonist for the farnesoid X receptor is obeticholic acid with experiments showing it has very strong affinity. A worry though is despite benefits in the biochemical pathways, pruritus was more intense and prevalent than the placebo. A titration strategy may help to mitigate pruritus, but FDA approval for obeticholic acid is currently unlikely. In fact, in February 2018, the FDA gave a black box warning for OCA. A recent study did find that if the drug is given with UDCA, the incidence for cirrhosis and liver transplants decreases. Another target that is being looked into is the all-trans retinoic acid (ATRA), an activator for the retinoid X receptor. In vitro and animal studies found ATRA had lowered the amount of bile acid and decreased hepatic inflammation.
In 1959, Nikita Khrushchev launched an anti-religious campaign. Of the 50 churches that were operating in Moscow in 1959, 30 were closed and six demolished. On 8 May 1965, the 20th anniversary of the Soviet victory in World War II, Moscow was awarded the honorary title of Hero City. The Moscow Ring Road (MKAD) was opened in 1961. It had four lanes running 109 kilometers (68 mi) along city borders. The MKAD marked the administrative boundaries of the city until the 1980s, when outlying suburbs beyond the ring road were incorporated. In 1980, Moscow hosted the Summer Olympic Games, which were boycotted by the United States and other Western countries because the Soviet Union invaded Afghanistan in 1979. In 1991, Moscow was the scene of a coup attempt by conservative communists opposed to the liberal reforms of Mikhail Gorbachev.
Sources: en.wikipedia.org
==== Placental production ==== The role of the placenta in progestogen production varies by species. In the sheep, horse, and human, the placenta takes over the majority of progestogen production, whereas in other species the corpus luteum remains the primary source of progestogens. In the sheep and human, progesterone is the major placental progestogen. The equine placenta produces a variety of progestogens, primarily 5α-dihydroprogesterone and 5α,20α-tetrahydroprogesterone, beginning on day 60. A complete luteo-placental shift occurs by day 120–150.
== History == Metandienone was first described in 1955. It was synthesized by researchers at the CIBA laboratories in Basel, Switzerland. CIBA filed for a U.S. patent in 1957, and began marketing the drug as Dianabol in 1958 in the U.S. It was initially prescribed to burn victims and the elderly. It was also prescribed off-label as a pharmaceutical performance enhancement to weight lifters and other athletes. Early adopters included players for Oklahoma University and San Diego Chargers head coach Sid Gillman, who administered Dianabol to his team starting in 1963. After the Kefauver Harris Amendment was passed in 1962, the U.S. FDA began the DESI review process to ensure the safety and efficacy of drugs approved under the more lenient pre-1962 standards, including Dianabol. In 1965, the FDA pressured CIBA to further document its legitimate medical uses, and re-approved the drug for treating post-menopausal osteoporosis and pituitary-deficient dwarfism. After CIBA's patent exclusivity period lapsed, other manufacturers began to market generic metandienone in the U.S. Following further FDA pressure, CIBA withdrew Dianabol from the U.S. market in 1983. Generic production shut down two years later, when the FDA revoked metandienone's approval entirely in 1985. Non-medical use was outlawed in the U.S. under the Anabolic Steroids Control Act of 1990. While metandienone is controlled and no longer medically available in the U.S., it continues to be produced and used medically in some other countries.
=== Intake === In the developed world, the estimated daily intake of CoQ10 has been determined at 3–6 mg per day, derived primarily from meat. South Koreans have an estimated average daily CoQ (Q9 + Q10) intake of 11.6 mg/d, derived primarily from kimchi.
Sources: en.wikipedia.org
电喷雾或基质辅助激光解吸电离质谱是常用手段,测得的质子化离子质荷比可换算为分子量。结果与理论值落在合理误差内,才支持结构一致的判断。
甲硫氨酸侧链含硫醚,在氧气、光照或金属离子存在时容易被氧化。氧化产物极性略增,常在色谱图上表现为主峰之前的肩峰或前伸峰。
通常建议冷藏避光,并在较短时间内使用。不存在适用于所有配方的统一期限,具体取决于浓度、缓冲体系与容器材质。
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.