If you have been reading about heptapeptide and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-07-22. Numbers and descriptions here follow the published literature rather than marketing material.
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。
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应,Semax 属于这一路线。鼻内给药是其主要使用方式,俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上,样本规模与终点设置同西方试验惯例存在差异,国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理,部分东欧国家留有使用记录;欧盟与美国未批准其作为药物上市,市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录,跨境携带则受目的地药品法规约束。
Semax 是人工设计的七肽,序列为 Met-Glu-His-Phe-Pro-Gly-Pro,骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性,同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
| 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 |
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
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.
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.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Keratoconus Global Award (2009) for his work on CXL technology. Carl Camras Award 2014 for translational research (Association for Research in Vision and Ophthalmology [ARVO]) The 2014 IIRSI Gold Medal for his efforts in introducing CXL into clinical ophthalmology Member of The Ophthalmologist Power List Top 100 (2014, 2016, 2018, 2020, and 2023) Casebeer Award (2014) of the International Society for Refractive Surgery. The 2016 El-Maghraby International Award for his contributions to ophthalmology The 2016 Gold Medal of SAMIR for his pioneering work on corneal cross-linking Elected as an honorary member of Hungary's SHIOL (Societas Hungarica Ad Implantandam Oculi Lenticulam) in 2016 Appointed FARVO (Fellow of ARVO) in 2019 Additionally, in 2012, Hafezi and his colleague, Dr. Olivier Richoz, won the University of Geneva's INNOGAP award for the development of a disposable medical device (the C-Eye device) for performing PACK-CXL. Hafezi is one of the most cited ophthalmologists of his generation, with a h index of 45 and a total more than 7,700 citations in the scientific literature.
Sweet soups and desserts Beverages combined with milk or soy milk Porridges and puddings Combined with other ingredients such as snow fungus, red dates, or papaya The texture after preparation is described as gelatinous and slightly chewy.
Isotope masses from: Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001 Isotopic compositions and standard atomic masses from: de Laeter, John Robert; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry. 75 (6): 683–800. doi:10.1351/pac200375060683. Wieser, Michael E. (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry. 78 (11): 2051–2066. doi:10.1351/pac200678112051. "News & Notices: Standard Atomic Weights Revised". International Union of Pure and Applied Chemistry. 19 October 2005. Half-life, spin, and isomer data selected from the following sources. Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001 National Nuclear Data Center. "NuDat 3.0 database". Brookhaven National Laboratory. Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN 978-0-8493-0485-9.
In September 2026, a UN-commissioned fact-finding mission panel found "reasonable grounds" to believe that the United States had committed war crimes during military strikes in Iran during the 2026 Iran war. The report highlighted two 28 February strikes that killed at least 178 civilians. U.S. president Donald Trump's threats to completely destroy Iranian power plants and other essential infrastructure during the 2026 Iran war have been widely condemned by human rights organizations, legal experts, and lawmakers as potential war crimes. The report published by the Independent International Fact-Finding Mission on Iran detailed two specific U.S. military operations on the first day of the 2026 Iran war that it determined constituted indiscriminate attacks on civilian infrastructure, the Minab School Bombing, where a U.S. Tomahawk missile strike targeted the Shajareh Tayyebeh Primary School in the southern city of Minab. The attack killed more than 150 people, including approximately 120 children. The UN mission concluded that the school was the intended point of impact rather than collateral damage, as well as the Lamerd Sports Complex Strike, where a separate U.S. airstrike utilized precision strike missiles to disperse tungsten pellets over a clearly identifiable sports complex and residential area in Lamerd. The attack resulted in the deaths of 22 civilian men and women. The Trump administration firmly rejected the allegations. White House spokeswoman Anna Kelly dismissed the findings as "unserious nonsense," stating that the U.S.
Sources: en.wikipedia.org
The technology of fragrances came with the invention of distillation, which allowed to be concentrated and sometimes even separated into individual components. The purification of cinnamaldehyde, the first single component fragrance, marked the beginning of the fragrance and flavor industries. Other single component fragrance compounds that were purified in the 19th century include benzaldehyde, methyl salicylate (oil of wintergreen), and vanillin. Somewhat in step with the synthetic dye industry, the fragrance and flavor industry was established. Many fragrance compounds were prepared synthetically. Spectroscopic methods coupled with various separation techniques allowed the identification of traces of aroma compounds (e.g. in wines, flower extracts, etc.). Tetramethyl acetyloctahydronaphthalenes have been described as "the most successful synthetic fragrance". The invention of gas chromatography was very important to the development of fragrances. Gas chromatography-olfactometry sometimes involving a human operator sniffing the GC effluent is particularly relevant to the analysis of fragrances. GC-O and related techniques have also been developed to characterize individual enantiomers of chiral aromatic compounds. Studies on synthetic musk reveal that the odors of some compounds are noticeably affected by deuteration. Various fragrant fruits are commercially cultivated to have appealing or intensified aromas.
== Clinical significance == Within this section, the function of CK1δ in the occurrence, development and progress of several diseases and disorders mainly on cancers, neurological diseases and metabolic diseases will be discussed.
== History == Tuscaloosa succeeded Cahaba as Alabama's state capitol. The Childress Hill site fronting Broad Street and adjacent to the river was selected for the new capitol building, designed by English architect William Nichols. In 1829, Alabama Governor Gabriel Holmes addressed the legislature in the new building. The capitol building became Alabama Central Female College. It burned down in 1923.
Sources: en.wikipedia.org
Reversible inhibitors attach to enzymes with non-covalent interactions such as hydrogen bonds, hydrophobic interactions and ionic bonds. Multiple weak bonds between the inhibitor and the enzyme active site combine to produce strong and specific binding. In contrast to irreversible inhibitors, reversible inhibitors generally do not undergo chemical reactions when bound to the enzyme and can be easily removed by dilution or dialysis. A special case is covalent reversible inhibitors that form a chemical bond with the enzyme, but the bond can be cleaved so the inhibition is fully reversible. Reversible inhibitors are generally categorized into four types, as introduced by Cleland in 1963. They are classified according to the effect of the inhibitor on the Vmax (maximum reaction rate catalysed by the enzyme) and Km (the concentration of substrate resulting in half maximal enzyme activity) as the concentration of the enzyme's substrate is varied.
In June 2025, two months after India suspended the Indus Water Treaty over Pakistan's alleged "cross border linkages" to the Pahalgam Attack, Bhutto Zardari threatened war with India stating that "either India shares water fairly or we will secure it from ‘all 6 rivers.’" In August, at a function organized by the Culture Department of the Sindh government, Bhutto Zardari once again raised the prospect of war with India, citing escalating tensions over the Treaty. He warned that if India continued actions perceived as "violations of the treaty", Pakistan would be compelled to consider all options, including military action. He stated that the people of Pakistan were "strong enough" to wage war in order to "reclaim all six rivers".
In January 1877 Eddy spurned an approach from Daniel Spofford, and to everyone's surprise married another of her students, Asa Gilbert Eddy. Eddy already believed that her former student and business partner Richard Kennedy was plotting against her. Weeks after the wedding Spofford was suspected too. She had hinted in October 1876 that he might be a successor, but instead he was expelled from the Christian Scientists' Association for "immorality" after quarrelling with her over money. She filed lawsuits against him and others for royalties or unpaid tuition fees. McClure's wrote that Eddy required "absolute and unquestioning conformity" from her students. The conviction that she was at the center of plots and counter-plots became a feature of Eddy's life. She believed that several students were using what she called "malicious animal magnetism," or evil thought, against her. (She also referred to it as An. Mag., Mes., M.A.M., m.a.m., mesmerism, malicious mesmerism, animal magnetism, mental malpractice, malicious malpractice, and mental influence.) Wilson writes that the concept of malicious animal magnetism was an important one in Christian Science. In 1881 Eddy added a 46-page chapter on it, "Demonology", to Science and Health. From the 16th edition in 1886, when James Henry Wiggin became the book's editor, the chapter was reduced and renamed, and in the final edition is a seven-page chapter called "Animal Magnetism Unmasked". Eddy spoke openly about it, including to the press.
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。
不存在。它是依据 ACTH 的一段序列人工设计的分子,天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号,而非天然物质名。