neuropeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-09-06. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
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.
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 |
|---|---|---|
| Chemical class | Synthetic heptapeptide | ACTH(4-7) analogue |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Free N terminus, unmodified side chains |
| Molecular weight | 813.9 Da | Free base; salt forms differ |
| Appearance | White to off-white powder | Lyophilised solid |
| Solubility | Freely soluble in water | Hydrophilic; polar solvents preferred |
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
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.
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。
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.
==== Henry Clay ==== The facility at Henry Clay, also in New Orleans, was constructed in 2012 with 127,000 square feet (5,100,000 cubic feet) of cold storage warehouse with a total storage capacity of 38,000,000 pounds of product. This plant has riverfront bulk break access as well as direct access to the Port of New Orleans container port. This facility has two vessel berths and 20 dock doors and is located within one mile of the container terminal. This facility has access to all major U.S. rail carriers. It maintains USDA export certification and approval from the Russian confederation for poultry exports. It is especially designed to blast freeze meat and poultry at 0 degrees Fahrenheit within 24 hours with a total capacity of 1,240,000 lbs. a day.
The Ocean Race is a yacht race around the world, held every three or four years since 1973. Originally named the Whitbread Round the World Race after its initiating sponsor, British brewing company Whitbread, in 2001 it became the Volvo Ocean Race after Swedish automobile manufacturer Volvo took up the sponsorship, and in 2019 it was renamed The Ocean Race. Each of the entries has a sailing crew who race day and night for more than 20 days at a time on some of the legs. Since the 2008–2009 race there has also been a dedicated media crew member called the On Board Reporter (OBR), who does not contribute to the sailing of the boat, but is responsible for sending images and video to race headquarters via satellite from the middle of the ocean. In the 2017–2018 race, the number of crew ranged between 7 and 10 (plus the OBR) depending on the gender ratio, with the rules providing an incentive to having women sailors on board. To minimize weight, crews overwhelmingly rely on freeze-dried fare for sustenance. Crews are also subjected to temperature variations from −5 to +40 degrees Celsius and will often take only one change of clothes.
== Selected publications == Kiessling, Laura L.; Pohl, Nicola L. (1996-02-01). "Strength in numbers: non-natural polyvalent carbohydrate derivatives". Chemistry & Biology. 3 (2): 71–77. doi:10.1016/S1074-5521(96)90280-X. ISSN 1074-5521. PMID 8807830. Ko, Kwang-Seuk; Jaipuri, Firoz A.; Pohl, Nicola L. (2005-09-28). "Fluorous-Based Carbohydrate Microarrays". Journal of the American Chemical Society. 127 (38): 13162–13163. Bibcode:2005JAChS.12713162K. doi:10.1021/ja054811k. ISSN 0002-7863. PMID 16173741. Wacker, Michael; Feldman, Mario F.; Callewaert, Nico; Kowarik, Michael; Clarke, Bradley R.; Pohl, Nicola L.; Hernandez, Marcela; Vines, Enrique D.; Valvano, Miguel A.; Whitfield, Chris; Aebi, Markus (2006-05-02). "Substrate specificity of bacterial oligosaccharyltransferase suggests a common transfer mechanism for the bacterial and eukaryotic systems". Proceedings of the National Academy of Sciences. 103 (18): 7088–7093. Bibcode:2006PNAS..103.7088W. doi:10.1073/pnas.0509207103. ISSN 0027-8424. PMC 1459022. PMID 16641107.
=== Frank Wade === Frank Wade (Joel Kim Booster) is a research analyst at Pierpoint covering the energy sector. After the tumultuous IPO of green-energy startup Lumi, Wade publishes a research report with a "hold" recommendation on Lumi stock, which is tantamount to a "sell" given that Pierpoint underwrote the IPO.
Sources: en.wikipedia.org
Half-Life 2: Episode Two is a 2007 first-person shooter game developed and published by Valve. Following Episode One (2006), it is the second of two episodic games that continue the story of Half-Life 2 (2004). The player controls Gordon Freeman, who travels through the mountains surrounding City 17 to a resistance base with his ally Alyx Vance. Like previous Half-Life games, Episode Two combines shooting, puzzle-solving and narrative elements, and adds expansive environments and less linear sequences. Episode Two was released on October 10, 2007, for Windows on Valve's distribution service Steam, and as a part of The Orange Box, a compilation of Valve games for Windows, Xbox 360, and PlayStation 3. The PlayStation version was produced by Electronic Arts. Episode Two received positive reviews. Valve canceled Half-Life 2: Episode Three when they abandoned episodic development and began developing a new game engine. In 2020, after canceling several further Half-Life projects, Valve released Half-Life: Alyx.
There are very few cases of hypoparathyroidism. Most often, it is related with surgical removal of the parathyroid glands. It can also be due to a head or neck injury and further loss of function of the glands. Hypoparathyroidism can also be linked to a low serum magnesium level in the blood. Serum magnesium is necessary for full secretion of PTH. Without the parathyroid glands, there is no trigger to release calcium into the blood. Another consequence of hypoparathyroidism is the lack of calcium in the blood to trigger muscle contraction. Without calcium present, muscles innervation is unable to take place. This is especially crucial in the function of the most important muscle of the body – the heart.
== Neurons == The PVN contains magnocellular neurosecretory cells whose axons extend into the posterior pituitary, parvocellular neurosecretory cells that project to the median eminence, ultimately signalling to the anterior pituitary, and several populations of other cells that project to many different brain regions including parvocellular preautonomic cells that project to the brainstem and spinal cord.
Deployment of such agents began to accelerate in late 2023 after OpenAI's "function-calling" API was made available, and especially after Anthropic's late 2024 introduction of Model Context Protocol (MCP), a standardised way for LLM agents to gain contextual awareness, and to act on the world by calling various external tools. The term "agentic" only began to be used with any frequency in 2024, popularised in part by researcher Andrew Ng.
== Production == Homoarginine is formed as a derivative from lysine through reactions similar to those of the urea cycle. Just as in the urea cycle, in its synthesis, ornithine is replaced by lysine. Ornithine transcarbamylase is the main enzyme for homoarginine synthesis. The production of homoarginine is based around the activity of this enzyme. Although ornithine transcarbamylase has a higher affinity to ornithine, it ends up catalyzing the transaminidation reaction of lysine as well, which starts homoarginine production. The reason it also catalyzes this reaction with lysine is because of the low substrate selectivity in the reaction. Another pathway for the production of Homoarginine includes glycine amidinotransferase (AGAT). This enzyme normally acts through the transfer of an amidino group from arginine to glycine, resulting in formation of guanidinoacetic acid, which is subsequently methylated by guanidinoacetate methyltransferase (GAMT) to form creatine. However, glycine amidinotransferase (AGAT) sometimes acts by using lysine instead of glycine in the reaction, therefore lysine becomes the acceptor of the amidino group, resulting in the production of homoarginine.
Sources: en.wikipedia.org
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.
It contains the 4-7 fragment of adrenocorticotropic hormone extended at the C terminus. That truncation removes the region associated with steroidogenic activity. The design intent was to keep neurotrophic properties while avoiding full hormonal effects.
No natural source of the intact heptapeptide is known. It is produced by solid-phase peptide synthesis. Some related ACTH fragments arise as hormone processing products, but the Pro-Gly-Pro extension is a designed addition rather than a natural sequence.
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。