Everything below concerns intranasal delivery. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-10-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
该化合物于二十世纪八十年代在俄罗斯被开发,相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性,而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示,这一方向促成了多个相关短肽的合成与筛选,而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上,包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升,但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验,人体对照研究数量有限。因此,该化合物的作用机制在文献中属于活跃讨论,而非已经确立的定论。
Semax 是一种人工合成的七肽,氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro,单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物,但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly,Semax 替换了中间两个残基,并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
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。
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。
| Property | Value | Notes |
|---|---|---|
| 化学类别 | 合成七肽 | ACTH(4-10) 结构类似物 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | 单字母写作 MEHFPGP |
| 分子量 | 约 813.9 Da | 随确切形式和盐型略有变化 |
| 常见同义词 | ACTH(4-10) 类似物 | 俄语文献称 Семакс |
| 开发来源 | 俄罗斯 | 二十世纪八十年代 |
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
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.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
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.
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.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
Between the 3rd and 1st centuries BC, the Roman Republic established hegemony over the eastern Mediterranean, while its government developed into the one-person rule of an emperor. The Roman Empire enjoyed a period of relative stability until the 3rd century AD, when external threats and internal crises caused it to splinter, as regional armies acclaimed their generals as "soldier-emperors". One of these, Diocletian (r. 284–305), recognised that the state was too big to be ruled by a single person. He instituted the Tetrarchy, a system which divided the empire into eastern and western halves. The Tetrarchy quickly failed, but the division of the empire proved an enduring concept. Constantine I (r. 306–337) secured absolute power in 324. Over the next six years, he rebuilt the city of Byzantium as a new capital that he called "New Rome" (later named Constantinople). The old capital Rome was farther from the prosperous eastern provinces and in a less strategically important location; its esteem had already been somewhat lessened in the eyes of the "soldier-emperors", who ruled from the frontiers, and of the empire's population. Having been granted citizenship, the empire's subjects considered themselves just as Roman as those in the city of Rome. Constantine continued reforms of the empire's military and civil administration and instituted the gold solidus as a stable currency. He favoured Christianity and became an opponent of paganism.
In Uganda, cooking bananas are referred to as matooke or matoke, which is also the name of a cooking banana stew that is widely prepared in Kenya, Uganda, Tanzania, Rwanda and eastern Congo. The cooking bananas (specifically East African Highland bananas) are peeled, wrapped in the plant's leaves and set in a cooking pot (a sufuria) on the stalks that have been removed from the leaves. The pot is then placed on a charcoal fire and the matoke is steamed for a few hours. While uncooked, the matoke is white and fairly hard, but cooking turns it soft and yellow. The matoke is then mashed while still wrapped in the leaves and is served with a sauce made of vegetables, ground peanuts, or some type of meat such as goat or beef. Cayeye, also called Mote de Guineo, is a traditional Colombian dish from the Caribbean Coast of the country. Cayeye is made by cooking small green bananas or plantains in water, then mashing and mixing them with refrito, made with onions, garlic, red bell pepper, tomato and achiote. Cayeye are usually served for breakfast with fresh grated Colombian cheese (Queso Costeño) and fried fish, shrimp, crab, or beef. Most popular is Cayeye with fresh cheese, avocado and fried egg on top. Funche criollo, a dish served for breakfast or dinner, varies on ingredients. Breakfast funche is made with coconut milk, butter, milk, sugar, cornmeal, sweet plantains, and topped with cinnamon, honey, nuts and fruit. The dinner version typically includes green or yellow plantains boiled in broth, butter, sofrito and mashed with taro, cornmeal, or yams.
=== Europe === Marketing authorisation for 177Lu-DOTATATE was granted by the European Medicines Agency on 26 September 2017. 90Y-DOTATOC (international nonproprietary name: yttrium (90Y) edotreotide) and 177Lu-DOTATOC are designated as orphan drugs, but have not yet received marketing authorisation.
Sources: en.wikipedia.org
Hox genes A subset of highly conserved homeobox-containing genes whose protein products function as transcription factors essential for the proper organization of the body plan in developing animal embryos, ensuring that the correct structures are formed in the correct places. Hox genes are usually arranged on a chromosome in tandem arrays and are expressed sequentially during development, with the sequence of gene activation corresponding to their physical arrangement within the genome and/or the physical layout of the tissues in which they are expressed along the organism's anterior–posterior axis.
== Clinical significance == Gastroesophageal reflux disease (GERD) is a common disorder that occurs when stomach acid repeatedly flows back into the esophagus, this backwash of acid (reflux) also known as heartburn can irritate the lining of the esophagus. Most people are able to manage the discomfort of GERD with lifestyle changes and medications, notably proton pump inhibitors, and H2 blockers. Antacids may also be used to neutralise gastric acid. Sometimes, surgery may be needed to ease symptoms. Chronic inflammation of the gastric mucosa can lead to atrophic gastritis resulting in a decreased secretion of gastric acid, and consequent digestive problems. In hypochlorhydria and achlorhydria, gastric acid is either low or absent, respectively. This can potentially lead to less protection against ingested pathogens such as Vibrio or Helicobacter bacteria. In Zollinger–Ellison syndrome gastrin levels are increased, leading to excess gastric acid production, which can cause gastric ulcers. Hypercalcemia also increases gastrin and gastric acid and can cause ulcers. In diseases featuring excess vomiting, hypochloremic metabolic alkalosis (decreased blood acidity by H+ and chlorine depletion) may develop.
Joseph Abram, Le Havre: Modern City, 2011 Nathalie Castetz, Le Havre, Seine Estuary, Paris, Héliopoles, 2012, ISBN 978-2-919006-10-6 Franck Godard and Olivier Bouteiller, Le Havre, Déclics, 2011, ISBN 978-2-84768-231-1 Unusual Le Havre, Renée Grimaud, Les beaux jours, 2012, ISBN 978-2-35179-101-1 Jean-François Massé, Le Havre, attached port, Acanthe, 2003, ISBN 2-84942-003-4 Tristan Gaston-Breton, Le Havre 1802–2002: Two centuries of economic adventure, Le Cherche midi, 2002, ISBN 2-7491-0028-3 E. Simon, A. Fiszlewicz, Le Havre: What an Estuary!, Petit à Petit, 2002, ISBN 2-914401-26-4 Madeleine Brocard, Atlas of the Estuary of the Seine, Rouen, Presses de l'université de Rouen, 1996 Emanuelle Real, The Industrial Landscape of Basse-Seine, Connaissance du patrimoine en Haute-Normandie, 2009, ISBN 2-910316-33-5, 264 pages Jacques Basile and Didier Guyot, Another Blue City, Editions Point de Vues, 2011, 120 pages, ISBN 978-2-915548-63-1
Sources: en.wikipedia.org
N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD) is an enzyme that catalyzes the release of N-acylethanolamine (NAE) from N-acyl-phosphatidylethanolamine (NAPE). This is a major part of the process that converts ordinary lipids into chemical signals like anandamide and oleoylethanolamine. In humans, the NAPE-PLD protein is encoded by the NAPEPLD gene.
β-Alanine (beta-alanine) is a naturally occurring beta amino acid. Beta amino acids are amino acids in which the amino group is attached to the β-carbon atom (i.e. the carbon atom two carbon atoms away from the carboxylate group) instead of the more usual α-carbon atom for alanine (α-alanine). The IUPAC name for β-alanine is 3-aminopropanoic acid. Unlike its counterpart α-alanine, β-alanine has no stereocenter.
=== Against warts === Repeated daily application of silver nitrate can induce adequate destruction of cutaneous warts, but occasionally pigmented scars may develop. In a placebo-controlled study of 70 patients, silver nitrate given over nine days resulted in clearance of all warts in 43% and improvement in warts in 26% one month after treatment compared to 11% and 14%, respectively, in the placebo group.
== Types of signaling == Hormonal effects are dependent on where they are released, as they can be released in different manners. Not all hormones are released from a cell and into the blood until it binds to a receptor on a target. The major types of hormone signaling are:
Sources: en.wikipedia.org
不是。Semax 是完全人工合成的七肽,自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10),但序列经过了替换和延长。
Semax 被描述为 ACTH(4-10) 的结构类似物,两者共享部分序列特征。它保留了该片段的部分神经相关活性方向,但去除了完整片段带来的激素释放效应。二者并非同一物质,也不能互相替代。
加入的 Pro-Gly-Pro 三肽被普遍认为能提升分子对蛋白水解酶的稳定性。这种设计让短肽在体内维持时间更长。具体延长的程度以及不同组织中是否一致,文献中仍存在不同报告。
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。