Semax 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.
Last reviewed on 2026-05-23. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
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。
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。
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.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
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.
A trial with the primary objective of showing that the response to the investigational product is not clinically inferior to a comparative agent (active or placebo control). (ICH E9) Nonrandomized clinical trial
Soybean plants are vulnerable to a wide range of bacterial diseases, fungal diseases, viral diseases, and parasites. The primary bacterial diseases include bacterial blight, bacterial pustule and downy mildew affecting the soybean plant. The Japanese beetle (Popillia japonica) poses a significant threat to agricultural crops, including soybeans, due to its voracious feeding habits. Found commonly in both urban and suburban areas, these beetles are frequently observed in agricultural landscapes where they can cause considerable damage to crops like corn, soybeans, and various fruits. Soybean cyst nematode (SCN) is the worst pest of soybean in the US. Losses of 30% or 40% are common even without symptoms. The corn earworm moth and bollworm (Helicoverpa zea) is a common and destructive pest of soybean growth in Virginia. Soybeans are consumed by whitetail deer which may damage soybean plants through feeding, trampling and bedding, reducing crop yields by as much as 15%. Groundhogs are also a common pest in soybean fields, living in burrows underground and feeding nearby. One den of groundhogs can consume a tenth to a quarter of an acre of soybeans. Chemical repellents or firearms are effective for controlling pests in soybean fields.
absolute zero A theoretical condition concerning a system at the lowest limit of the thermodynamic temperature scale, or zero kelvins, at which the system does not emit or absorb energy (i.e. all atoms are at rest). By extrapolating the ideal gas law, the internationally agreed-upon value for absolute zero has been determined as −273.15 °C (−459.67 °F; 0.00 K).
Roseanne Park. Musician/Performer. For services to the United Kingdom COP 26 Presidency and advocacy for the 2021 United Nations Climate Change Conference of the Parties. Gina Cecile Petrie. Director, Department of Environment, Cayman Islands. For services to the Environment and to the community in the Cayman Islands. Richard Anthony Power. Orthopaedic Surgeon, University Hospitals of Leicester NHS Trust; Chair, Health Action Leicester in Ethiopia. For services to Health in Gondar, Northern Ethiopia. Natalie Ray Pray. Former President, the St George's Society, New York, United States of America. For services to UK/US Cultural Relations and to Philanthropy. Phillip Christopher Robinson. Team Leader, Foreign, Commonwealth and Development Office. For services to National Security. James Andrew Rogers. Head of Coordination, Windsor Framework Taskforce, Foreign, Commonwealth and Development Office. For services to British Foreign Policy. Lynette Silver. Historian and Author. For services to British Families of World War II personnel. Claire Sonia van Straubenzee. Founder and Trustee, The Henry van Straubenzee Memorial Fund. For services to Children's Education in Uganda. Edward Robert Syfret. Angola Programme Manager, the HALO Trust. For services to Humanitarian Demining in Angola. Margery Anne Taylor. District Treasurer and District Training Officer, Royal British Legion, Spain South. For services to Veterans in Spain. Jacqueline Barbara Teasdale (Tig James). Co-President, British in Portugal. For services to the British Community in Portugal. John Robert Thurlow.
Sources: en.wikipedia.org
It is removed under harsh conditions using HBr in acetic acid, or milder conditions of catalytic hydrogenation. This methodology was first used in the synthesis of oligopeptides by Zervas and Max Bergmann in 1932. Hence, this became known as the Bergmann-Zervas synthesis, which was characterized "epoch-making" and helped establish synthetic peptide chemistry as a distinct field. It constituted the first useful lab method for controlled peptide synthesis, enabling the synthesis of previously unattainable peptides with reactive side-chains, while Z-protected amino acids are also prevented from undergoing racemization. The use of the Bergmann-Zervas method remained the standard practice in peptide chemistry for two full decades after its publication, superseded by newer methods (such as the Boc protecting group) in the early 1950s. Nowadays, while it has been used periodically for α-amine protection, it is much more commonly used for side chain protection.
=== Approvals === The oral formulations of doxepin are FDATooltip Food and Drug Administration-approved for the treatment of depression and sleep-maintenance insomnia, and its topical formulations are FDA-approved the short-term management for some itchy skin conditions. In Australia and the United Kingdom, the only licensed indications are in the treatment of major depression and pruritus in eczema.
Despite his criticisms against Marcos, Duterte clarified the prayer rallies were not meant to overthrow the administration but warned Marcos of extending his six-year term, reminding Marcos of his father's fate.
From the early days of the development of AI, there have been arguments put forward by ELIZA creator Joseph Weizenbaum and others about whether tasks that can be done by computers actually should be done by them, given the difference between computers and humans, and between quantitative calculations and qualitative, value-based judgements. In April 2023, it was reported that image generation AI has resulted in 70% of the jobs for video game illustrators in China being lost. In July 2023, developments in generative AI contributed to the 2023 Hollywood labor disputes. Fran Drescher, president of the Screen Actors Guild, declared that "artificial intelligence poses an existential threat to creative professions" during the 2023 SAG-AFTRA strike. Voice generation AI has been seen as a potential challenge to the voice acting sector. However, a 2025 study concluded that the US labor market had so far not experienced a discernible disruption from generative AI. Another study reported that Danish workers who used chatbots saved 2.8% of their time on average, and found no significant change in earnings or hours worked.
== Use as a dietary supplement == Citicoline is available as a supplement in over 70 countries under a variety of brand names: CereBleu, Cebroton, Ceraxon, Cidilin, Citifar, Cognizin, Difosfocin, Hipercol, NeurAxon, Nicholin, Sinkron, Somazina, Synapsine, Startonyl, Trausan, Xerenoos, etc. When taken as a supplement, citicoline is hydrolyzed into choline and cytidine in the intestine. Once these cross the blood–brain barrier, they are reformed into citicoline by the rate-limiting enzyme in phosphatidylcholine synthesis, CTP-phosphocholine cytidylyltransferase.
Sources: en.wikipedia.org
==== Louis Vuitton fashion shows ==== Williams was hand-selected to be the new creative director of menswear at luxury fashion house Louis Vuitton in 2023. In a story with the New York Times about the job and his upcoming debut fashion show with the brand, an unheard song with Pusha T ("Chains & Whips") was teased, although it was not yet revealed as a Clipse song. The three annual spring–summer shows from this point until Let God Sort Em Out's release all featured new Clipse music in their soundtracks, along with other songs. "Chains & Whips" was debuted at the Louis Vuitton's Men's Spring–Summer Show 2024 on June 20, 2023, although Kendrick Lamar's guest verse was not yet included. Pusha T and Malice also walked on the runway in Williams's designs. For the Men's Spring–Summer Show 2025 on June 18, 2024, "The Birds Don't Sing" was previewed for the first time, featuring vocals by John Legend. The Men's Spring–Summer Show 2026 debuted "So Be It Pt. II" on June 24, 2025.
=== Part One === Part One is set during the second half of events of Half-Life 2: Episode One. Dr. Isaac Kleiner is making his "Kleinercasts" on City 17's PA system, warning that the Combine Citadel is set to explode at any moment; should the Citadel detonate, the resulting explosion will destroy the city and the surrounding area. Prior to the film's events, Gordon Freeman's actions within the Citadel have held down the impending explosion, opening a small window of time for civilians to escape. Members of the Lambda Resistance are seen fighting their way out of the city as the Combine's Civil Protection forces try to hold them back. CP officers are also seen executing captured rebels, while Combine synths wreak havoc on the warzone. Two male Resistance members (Derek Chan and Ian Purchase) are introduced escaping through an overrun trainyard. Through radio communication, the two learn from a third rebel (David Purchase) that the last evacuation train has already left, and are urged to escape the city on foot through the canal system (a route similar to that of Gordon Freeman's in Half-Life 2) in order to catch up with David, who is en route to the Resistance stronghold of White Forest. After a brief argument, the two resolve to escape City 17 before "the Citadel blows us up first". Suddenly, CP officers appear and fire on the Resistance members. The two retaliate with their own weaponry (Derek using a 9mm pistol, then a crowbar found hanging on a handrail; Ian using an SMG with a grenade launcher) and manage to escape.
By-products of the reaction are diethylene glycol, triethylene glycol, and polyglycols with the total of about 10%, which are separated from the ethylene glycol by distillation at reduced pressure. Another synthesis method is the reaction of ethylene oxide and CO2 (temperature 80–120 °C (176–248 °F) and pressure of 5.2 MPa (750 psi)) yielding ethylene carbonate and its subsequent hydrolysis with decarboxylation:
Recently, sequence context-specific amino acid similarities have been derived that do not need substitution matrices but that rely on a library of sequence contexts instead. Using this idea, a context-specific extension of the popular BLAST program has been demonstrated to achieve a twofold sensitivity improvement for remotely related sequences over BLAST at similar speeds (CS-BLAST).
The HEVC encoder has 17 3G-SDI inputs and uses 17 boards for parallel processing with each board encoding a row of 7680 × 256 pixels to allow for real time video encoding. The HEVC encoder is compliant with draft 4 of the HEVC standard and has a maximum bit rate of 340 Mbit/s. The HEVC encoder was shown at the NHK Science & Technology Research Laboratories Open House 2013 that took place from May 30 to June 2. At the NHK Open House 2013 the HEVC encoder used a bit rate of 85 Mbit/s, which gives a compression ratio of 350∶1. On May 21, 2013, Microsoft announced the Xbox One, which supports 4K resolution (3840 × 2160) video output and 7.1 surround sound. Yusuf Mehdi, corporate vice president of marketing and strategy for Microsoft, has stated that there is no hardware restriction that would prevent Xbox One games from running at 4K resolution. On May 30, 2013, Eye IO announced that their encoding technology was licensed by Sony Pictures Entertainment to deliver 4K Ultra HD video. Eye IO encodes their video assets at 3840 × 2160 and includes support for the xvYCC color space. In mid-2013, a Chinese television manufacturer produced the first 50-inch UHD television set costing less than $1,000. On June 11, 2013, Comcast announced that they had demonstrated the first public U.S.-based delivery of 4K Ultra HD video at the 2013 NCTA show. The demonstration included segments from Oblivion, Defiance, and nature content sent over a DOCSIS 3.0 network.
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
Each freeze-thaw cycle can degrade a fraction of the peptide and promote aggregation. Dividing a stock solution into single-use volumes removes repeated cycling as a variable. It also limits the time a thawed solution spends at room temperature.