Everything below concerns methionine sulfoxide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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。
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.
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.
| 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 |
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下,同时避免光照与反复升温。短期运输有时采用冷藏条件,但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数,以降低吸湿和微生物污染的风险。开封后若未一次用完,建议在干燥环境中密封并尽快放回低温储存。
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集,其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸,因此氧化风险相对突出。工作液一般主张现配现用,或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率,而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱,并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成,肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同,因此各实验室报告的纯度数值不宜直接横向比较。
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
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.
===== Secondary infection ===== While a primary infection can practically be viewed as the root cause of an individual's current health problem, a secondary infection is a sequela or complication of that root cause. For example, an infection due to a burn or penetrating trauma (the root cause) is a secondary infection. Primary pathogens often cause primary infection and often cause secondary infection. Usually, opportunistic infections are viewed as secondary infections (because immunodeficiency or injury was the predisposing factor).
=== Functional categorization === Nonsense mutations include stop-gain and start-loss. Stop-gain is a mutation that results in a premature termination codon (a stop was gained), which signals the end of translation. This interruption causes the protein to be abnormally shortened. The number of amino acids lost mediates the impact on the protein's functionality and whether it will function whatsoever. Stop-loss is a mutation in the original termination codon (a stop was lost), resulting in abnormal extension of a protein's carboxyl terminus. Start-gain creates an AUG start codon upstream of the original start site. If the new AUG is near the original start site, in-frame within the processed transcript and downstream to a ribosomal binding site, it can be used to initiate translation. The likely effect is additional amino acids added to the amino terminus of the original protein. Frame-shift mutations are also possible in start-gain mutations, but typically do not affect translation of the original protein. Start-loss is a point mutation in a transcript's AUG start codon, resulting in the reduction or elimination of protein production. Missense mutations code for a different amino acid. A missense mutation changes a codon so that a different protein is created, a non-synonymous change. Conservative mutations result in an amino acid change. However, the properties of the amino acid remain the same (e.g., hydrophobic, hydrophilic, etc.) At times, a change to one amino acid in the protein is not detrimental to the organism as a whole.
During the years that followed, Gaddafists adopted quotes from The Green Book, such as "Representation is Fraud", as slogans. Meanwhile, in September 1975, Gaddafi implemented further measures to increase popular mobilization, introducing objectives to improve the relationship between the Councils and the ASU. In 1975, Gaddafi's government declared a state monopoly on foreign trade. Its increasingly radical reforms, coupled with the large amount of oil revenue being spent on foreign causes, generated discontent in Libya, particularly among the country's merchant class. In 1974, Libya saw its first civilian attack on Gaddafi's government when a Benghazi army building was bombed. Much of the opposition centred around RCC member Umar Muhayshi. With fellow RCC members Bashir Saghir al-Hawaadi and Awad Ali Hamza, he began plotting a coup against Gaddafi. In 1975, their plot was exposed and Muhayshi fled to Tunisia, eventually receiving asylum from Sadat's Egypt. Hawaadi, Hamza, and Omar El-Hariri were arrested. Most of the other conspirators were executed in March 1976. Another RCC member, foreign minister Abdul-Munim al-Huni, also fled to Egypt. In the aftermath, only five RCC members remained: Gaddafi, Jalloud, Abu-Bakr Yunis Jabr, Mustafa Kharubi, and Kweldi al-Hamidi. Thus, power was further concentrated in Gaddafi's hands. This ultimately led to the RCC's official abolition in March 1977. In September 1975, Gaddafi purged the army, arresting around 200 senior officers, and in October he founded the clandestine Office for the Security of the Revolution.
=== Infants and microwave ovens === There are several cases of child abuse where an infant or child has been placed in a microwave oven. The typical feature of such injuries are well-defined burns on the skin nearest to the microwave emitter, and histology examination shows higher damage extent in tissues with high content of water (e.g., muscles) than in tissues with less water (e.g., adipose tissue). One such case involved a teenage babysitter who admitted to having placed a child in the microwave oven for approximately sixty seconds. The child developed a third degree burn to the back, measuring 5 inches x 6 inches. The babysitter later took the child to the emergency department, where multiple skin grafts were placed on the back. There were no signs of lasting emotional, cognitive or physical effects. CT scan of the head was normal, and there were no cataracts. Another case involved a five-week-old female infant that had multiple full-thickness burns totaling 11% of the body surface area. The mother claimed the infant had been near a microwave oven, but not inside it. The infant survived but required amputations of parts of one leg and one hand. Additionally, there have been two alleged infant deaths caused by microwave ovens. In all these cases, the babies were placed within microwaves and died of subsequent injuries.
Sources: en.wikipedia.org
PFOA exposure in the Danish general population was not associated with an increased risk of prostate, bladder, pancreatic, or liver cancer. Maternal PFOA levels were not associated with an offspring's increased risk of hospitalization due to infectious diseases, behavioral and motor coordination problems, or delays in reaching developmental milestones.
=== Book bans === In May 2023, during a commencement speech at Morehouse College, Moore criticized efforts to ban books and restrict curriculum in schools, suggesting that politicians who sought to "silence or rewrite the history of Black and brown people are actually afraid of people understanding their power". In April 2024, Moore signed into law the Freedom to Read Act, which prohibits public and school libraries from banning books based on partisan, ideological, or religious reasons, or based an author's origin, background, or views.
=== Oily skin === Healthy sebaceous glands produce a substance called sebum, a naturally healthy skin lubricant. When the skin produces excessive sebum, it becomes heavy and thick in texture, known as oily skin. Oily skin is typified by shininess, blemishes and pimples. The oily-skin type is not necessarily bad, since such skin is less prone to wrinkling, or other signs of ageing, because the oil helps to keep needed moisture locked into the epidermis (outermost layer of skin). The negative aspect of the oily-skin type is that oily complexions are especially susceptible to clogged pores, blackheads, and buildup of dead skin cells on the surface of the skin. Oily skin can be sallow and rough in texture and tends to have large, clearly visible pores everywhere, except around the eyes and neck. A high glycemic-index diet and dairy products (except for cheese) consumption increase IGF-1 generation, which in turn increases sebum production. Overwashing the skin does not cause sebum overproduction but may cause dryness; it is possible to have skin that is both dry and oily.
Sources: en.wikipedia.org
Back pain can also be referred from another source. Referred pain occurs when pain is felt at a location different than the source of the pain. Disease processes that can present with back pain include pancreatitis, kidney stones, severe urinary tract infections and abdominal aortic aneurysms.
== Works == Gish, Duane T. 15 Scopus Publishers. Gish, Duane T. (1972). Speculations and Experiments on the Origins of Life. New Leaf Pr. ISBN 0-89051-010-5. Gish, Duane T. (1972). Evidence against evolution. Wheaton, Ill: Tyndale House Publishers. ISBN 0-8423-0790-7. Gish, Duane T. (1986) [1972]. Evolution, the fossils say no!. San Diego, Calif: Institute for Creation Research Publishing. ISBN 0-89051-057-1. Gish, Duane T. (1973). Have You Been... Brainwashed?. Seattle, Washington: Life Messengers. p. 32. OCLC 10930514. Hillestad, George M.; Morris, Henry; Gish, Duane T. (1974). Creation: acts, facts, impacts. San Diego, Calif: ICR Pub. Co. ISBN 0-89051-020-2. Gish, Duane T. (1977). Dinosaurs: Those Terrible Lizards. Green forest, Arkansas: Master Books. ISBN 0-89051-039-3. Rohrer, Donald H.; Gish, Duane T. (1978). Up with creation!: ICR acts/facts/impacts, 1976-1977. San Diego, California: Creation-Life Publishers. ISBN 0-89051-048-2. Gish, Duane T.; Wilson, Clifford (1981). Manipulating life, where does it stop?: Genetic engineering. Green Forest, Arkansas: Master Books. ISBN 0-89051-071-7. Gish, Duane T. (1985). Evolution: the challenge of the fossil record. San Diego, Calif: Creation-Life Publishers. ISBN 0-89051-112-8. Gish, Duane T. (1988). Creationist Research 1964-1988. Creation Research Society. ISBN 0-940384-06-X. Bonnie Snellenberger; Gish, Duane T.; D Dish; Earl Snellenberger (1990). The Amazing Story of Creation: From Science and the Bible. Green Forest, Arkansas: Master Books. ISBN 0-89051-120-9.
==== UK ==== Loperamide can be sold freely to the public and is available in most supermarkets, convenience stores and chemists for the treatment of diarrhea and acute diarrhea associated with medically diagnosed irritable bowel syndrome to adults 18 years of age and older.
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。
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.