Everything below concerns RP-HPLC. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-02-16. Numbers and descriptions here follow the published literature rather than marketing material.
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。
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。
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.
| 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 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。
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。
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
The federation can be granted exclusive legislative authority. In this case, the federation alone is authorized to legislate in this area. This applies, for example, to foreign and defense policy. The federation can be granted the right to concurrent legislation. In this case, the federation and the states can both enact laws in the respective area; in case of doubt, however, a federal law takes precedence over a state law. This applies, for example, to tax law. In other areas, only the states are authorized to legislate; this includes, among other things, police law and culture (which in Germany also encompasses the school, vocational training, and university systems). Even in the areas that the Basic Law assigns to the federal government in whole or in part, the states retain influence on legislation, since the state governments are involved in legislation at the federal level through the Bundesrat. Above all, the federal government can only assume additional powers that have so far resided with the states if the constitution is amended, which requires, among other things, a two-thirds majority in the Bundesrat. The states cannot therefore be disempowered against their will.
Other: Other tools to monitor remission in rheumatoid arthritis are: ACR-EULAR Provisional Definition of Remission of Rheumatoid arthritis, Simplified Disease Activity Index and Clinical Disease Activity Index. Some scores do not require input from a healthcare professional and allow self-monitoring by the person, like HAQ-DI.
Cinnarizine is an antihistamine and calcium channel blocker of the diphenylmethylpiperazine group. It is prescribed for nausea and vomiting due to motion sickness or other sources such as chemotherapy, vertigo, or Ménière's disease. Cinnarizine is one of the leading causes of drug-induced parkinsonism. Cinnarizine was first synthesized as R1575 by Janssen Pharmaceutica in 1955. The nonproprietary name is derived from the cinnamyl substituent on the free nitrogen atom of the benzhydrylpiperazine core, combined with the generic ending "-rizine" for "antihistaminics/cerebral (or peripheral) vasodilators". It is not available in the United States or Canada. It has also been cited as one of the most used drugs for seasickness within the British Royal Navy.
Sources: en.wikipedia.org
dendrite Any of multiple freely branching protoplasmic processes extending from a vertebrate nerve cell that receive electrical signals from other nerve cells or sensory receptors and integrate them in order to generate electrical impulses known as action potentials. These pulse-like changes in electrical polarity are then propagated along an axon and transmitted to other cells.
=== Anti-mold === In certain cases, a nystatin derivative has been used to prevent the spread of mold on objects such as works of art. For example, it was applied to wood panel paintings damaged as a result of the Arno River Flood of 1966 in Florence, Italy.
==== Wound healing ==== Clients who are cleaned by blue tang benefit after suffering an injury. Blue tangs incur many minor injuries, but infection as a result of injuries rarely leads to death. Recovery rates from both minor and major injuries are very high in blue tangs. Injured blue tangs are found to spend more time in cleaning stations compared to those further along in the healing process. This indicates that cleaning plays an important role in the wound healing process. Cleaners pick at the wound and eat the dead tissue in the peripheral area.
Sources: en.wikipedia.org
== Results == The procedure results in a decrease in nearsightedness. According to the PERK study, 58% of eyes were corrected within 1.00D of goal 3 years after surgery. Additionally, 76% of eyes had uncorrected vision of 20/40 or better at 3 years. From 2 to 10 years post-operatively 43% of eyes had an increase in farsightedness by 1.00D or more. Despite this, 70% of patients reported not requiring corrective lenses for distance vision 10 years after surgery.
In the Histidine variant, the enzyme is much more effective at the aforementioned conversion. The enzyme responsible for the conversion of acetaldehyde to acetate, however, remains unaffected, which leads to differential rates of substrate catalysis and causes a buildup of toxic acetaldehyde, causing cell damage. This provides some protection against excessive alcohol consumption and alcohol dependence (alcoholism). Various haplotypes arising from this mutation are more concentrated in regions near Eastern China, a region also known for its low alcohol tolerance and dependence. A study was conducted in order to find a correlation between allelic distribution and alcoholism, and the results suggest that the allelic distribution arose along with rice cultivation in the region between 12,000 and 6,000 years ago. In regions where rice was cultivated, rice was also fermented into ethanol. This led to speculation that increased alcohol availability led to alcoholism and abuse, resulting in lower reproductive fitness. Those with the variant allele have little tolerance for alcohol, thus lowering chance of dependence and abuse. The hypothesis posits that those individuals with the Histidine variant enzyme were sensitive enough to the effects of alcohol that differential reproductive success arose and the corresponding alleles were passed through the generations. Classical Darwinian evolution would act to select against the detrimental form of the enzyme (Arg variant) because of the lowered reproductive success of individuals carrying the allele.
Independence stimulated the development of Polish culture in the Interbellum and intellectual achievement was high. Warsaw, whose population almost doubled between World War I and World War II, was a restless, burgeoning metropolis. It outpaced Kraków, Lwów and Wilno, the other major population centers of the country. Mainstream Polish society was not affected by the repressions of the Sanation authorities overall; many Poles enjoyed relative stability, and the economy improved markedly between 1926 and 1929, only to become caught up in the global Great Depression. After 1929, the country's industrial production and gross national income slumped by about 50%. The Great Depression brought low prices for farmers and unemployment for workers. Social tensions increased, including rising antisemitism. A major economic transformation and multi-year state plan to achieve national industrial development, as embodied in the Central Industrial Region initiative launched in 1936, was led by Minister Eugeniusz Kwiatkowski. Motivated primarily by the need for a native arms industry, the initiative was in progress at the time of the outbreak of World War II. Kwiatkowski was also the main architect of the earlier Gdynia seaport project.
Rhodiola rosea (commonly golden root, rose root, roseroot, Aaron's rod, Arctic root, king's crown, lignum rhodium, orpin rose) is a perennial flowering plant in the family Crassulaceae. It grows naturally in wild Arctic regions of Europe (including Britain), Asia, and North America (New Brunswick, Newfoundland and Labrador, Nova Scotia, Quebec; Alaska, Maine, New York, North Carolina, Pennsylvania, Vermont), and can be propagated as a groundcover. Although Rhodiola rosea has been used in traditional medicine, there is no high-quality clinical evidence of its effectiveness to treat any disease. The United States Food and Drug Administration has issued several warnings to manufacturers of R. rosea based dietary supplements for making false health claims about safety and efficacy. The plant is threatened in many countries due to rapidly growing demand. R. rosea has been identified by various farmers and researchers as a potential cash crop naturally suited for cultivation in Arctic climates. Supply comes mostly from wild harvesting on an industrial scale, and a combination of growing scarcity and a lack of regulation has led to environmental degradation, substitution or adulteration in the market, and illegal harvesting in protected areas.
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。
Reversed-phase high-performance liquid chromatography is the standard method, with detection in the ultraviolet range. Peak area percentage yields a purity figure for the main component. Mass spectrometry is normally run alongside to confirm molecular identity.