This is a working overview of intranasal delivery, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-07-18. 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 proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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.
| 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 |
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
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.
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.
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.
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.
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。
Haas solved for the Planck constant using the then-current value for the radius of the hydrogen atom. Three years later, Bohr would use similar equations with different interpretation. Bohr took the Planck constant as given value and used the equations to predict, a, the radius of the electron orbiting in the ground state of the hydrogen atom. This value is now called the Bohr radius.
Hitchens supported Ralph Nader in the 2000 US presidential election. He elaborated on his support for Nader in a discussion with Eric Alterman on Bloggingheads.tv, indicating that he was disenchanted with the candidacy of both George W. Bush and Al Gore. Prior to the September 11 attacks in 2001, and the invasion of Iraq and Afghanistan, Hitchens was critical of President George W. Bush's "non-interventionist" foreign policy. He also criticised Bush's support for intelligent design and capital punishment. Hitchens defended Bush's post-11 September foreign policy, but he also criticised the actions of US troops in Abu Ghraib and Haditha, and the US government's use of waterboarding, which, after voluntarily undergoing it, he argued was definitely torture. After Dick Cheney chief of staff Scooter Libby was found guilty of obstruction of justice and perjury, Hitchens defended Libby and called on Bush to pardon him. Hitchens supported George W. Bush in the 2004 US presidential election. He made a brief return to The Nation just before the election and wrote that he was "slightly" for Bush; shortly afterwards, Slate polled its staff on their positions on the candidates and mistakenly printed Hitchens' vote as pro-John Kerry. Hitchens shifted his opinion to "neutral", saying: "It's absurd for liberals to talk as if Kristallnacht is impending with Bush, and it's unwise and indecent for Republicans to equate Kerry with capitulation. There's no one to whom he can surrender, is there? I think that the nature of the jihadist enemy will decide things in the end".
Pictures of scarification in Africa – Features by Jean-Michel Clajot, Belgian photographer and Saï Sotima Tchantipo Doctor Anthropology Extensive Scarification Article – Features different scarification techniques and advice BME Website – Chronicles the current and historical body modifications world internationally Scarification – entry in BME Encyclopedia
==== Disbandment ==== Though it was not until October 1999 that the split was made official, on 12 September 1998, William had a falling out in the tour bus with Lurie, the guitarist, before they were to play a sold out performance at the famous Los Angeles House of Blues. Jim appeared onstage apparently drunk and barely able to stand or sing. William walked offstage about 15 minutes into their set, and the show ended. The audience was later refunded the price of their tickets. The band finished up their U.S. and Japanese dates without William, but from that point, it was clear that the band was at its end. Jim Reid said in 2006 of the tension between himself and William: "After each tour we wanted to kill each other, and after the final tour we tried". On the final night of the tour in Providence, Rhode Island, the band's promoter ran off with the money and the band reportedly got in a fight with the cast of the show Riverdance.
Sources: en.wikipedia.org
== External links == Long, Nguyen Van Duc; Sengupta, Sourjo; Zhuang, Changping; Richter, Katharina; Hessel, Volker (January 2026). "Plasma-activated water in agriculture, food safety, and healthcare". Chemical Engineering Journal. 528 172535. Bibcode:2026ChEnJ.52872535L. doi:10.1016/j.cej.2025.172535. Plasma Activated Water [PAW] Application Note Wong, Kiing S.; Chew, Nicholas S. L.; Low, Mary; Tan, Ming K. (23 July 2023). "Plasma-Activated Water: Physicochemical Properties, Generation Techniques, and Applications". Processes. 11 (7): 2213. doi:10.3390/pr11072213. Plasma activated water Xiang, Qisen; Fan, Liumin; Li, Yunfei; Dong, Shanshan; Li, Ke; Bai, Yanhong (20 March 2022). "A review on recent advances in plasma-activated water for food safety: current applications and future trends". Critical Reviews in Food Science and Nutrition. 62 (8): 2250–2268. Bibcode:2022CRFSN..62.2250X. doi:10.1080/10408398.2020.1852173. PMID 33261517. The power of plasma: turning water into an eco-friendly disinfectant Scholtz, Vladimír; Jirešová, Jana; Lokajová, Eliška; Měřínská, Tereza; Thonová, Laura; Šerá, Božena (July 2025). "Is Plasma Activated Water Really Magical? A Reflection on the Phenomenon". Plasma Chemistry and Plasma Processing. 45 (4): 1337–1351. Bibcode:2025PCPP...45.1337S. doi:10.1007/s11090-025-10565-0. Gan, Dingwei; Hong, Longfei; Yuan, Shuai; Zhu, Mengying; Gao, Yuting; Zhang, Tianqi; Li, Tianyu; Chen, Bohan; Dzimitrowicz, Anna; Jamroz, Piotr; Cullen, Patrick J.; Zhou, Renwu (2025).
=== Food tracing systems === The first prize went to Dominique Grégoire from the company TechniGREG who developed new tracing systems: TraciLOG and TraciMEAL. This improved monitoring of the cold chain is a major step forward as far as consumer safety is concerned. The principle is to endow each mobile container with "electronic intelligence", thus enabling it to log each of the phases through which it passes, monitor its internal temperature and record information about whether its doors are open or closed. This information is gathered automatically and securely, without any contact with the contents, and requires no human intervention. It is a reliable global management indicator for use by the logistics service in charge of maintaining the cold chain. Altran engineers worked side by side with the prize-winner, on conducting market studies, on the choice of suppliers, at developing product packaging, on the design of an electronic module and on the transition to the production stage for both TraciLOG and TraciMEAL. After the support, TechniGREG increased its capital of more than 1 million euros. The efforts of these teams were rewarded in March 2001, when a fully operational version of TraciLOG was installed for the first time by a supermarket distributor. TraciMEAL was adopted last May by an institutional food service provider in Toulouse. Since then, TechniGREG, which has registered many patents related to this innovation, has come into business with many companies, particularly in the air transport sector.
==== Syncytium formation and direct cell-to-cell infection transmission ==== Two of SeV proteins: HA and F, after their binding directly to a cellular membrane, promote a cell-cell fusion, which leads to a large multinuclear cell formation (syncytium). This formation involves the fusion of infected cells with adjacent target cells and remains an important mechanism of direct cell-to-cell spread of viral components. Thus, a SeV infection in a form of genetic material in partially assembled virions can spread without any exposure to host neutralizing antibodies (see the section "Directed cells fusion (syncytium formation)" for details and references).
Sources: en.wikipedia.org
As a matter of fact, Millennials and Generation Z have given life to nostalgia as an industry in the late 2010s and early 2020s, a trend that coincides with the resurgence of some cultural phenomena of the late 1990s and early 2000s (Y2K), such the television series Friends (1994–2004), something that is well-received among young people despite its age. Nostalgia has also contributed to the anticipation and subsequent commercial success of the summer film Barbie (2023) based on a well-known doll of the same name, even though it was intended for adults rather than children. Millennials and Generation Z on average begin using cosmetics in their mid-teens, or a few years earlier than the Baby Boomers and Generation X.
=== Data validation === Data validation is the application of validation rules to the data. For electronic CRFs the validation rules may be applied in real time at the point of entry. Offline validation may still be required (e.g. for cross checks between data types)
Pyrolysis is the basis of several methods for producing fuel from biomass, i.e. lignocellulosic biomass. Crops studied as biomass feedstock for pyrolysis include native North American prairie grasses such as switchgrass and bred versions of other grasses such as Miscantheus giganteus. Other sources of organic matter as feedstock for pyrolysis include greenwaste, sawdust, waste wood, leaves, vegetables, nut shells, straw, cotton trash, rice hulls, and orange peels. Animal waste including poultry litter, dairy manure, and potentially other manures are also under evaluation. Some industrial byproducts are also suitable feedstock including paper sludge, distillers grain, and sewage sludge. In the biomass components, the pyrolysis of hemicellulose happens between 210 and 310 °C. The pyrolysis of cellulose starts from 300 to 315 °C and ends at 360–380 °C, with a peak at 342–354 °C. Lignin starts to decompose at about 200 °C and continues until 1000 °C. Synthetic diesel fuel by pyrolysis of organic materials is not yet economically competitive. Higher efficiency is sometimes achieved by flash pyrolysis, in which finely divided feedstock is quickly heated to between 350 and 500 °C (660 and 930 °F) for less than two seconds. Syngas is usually produced by pyrolysis. The low quality of oils produced through pyrolysis can be improved by physical and chemical processes, which might drive up production costs, but may make sense economically as circumstances change.
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。
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.