neurotrophic factor raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-10-14. Anything still debated is marked as such rather than presented as settled.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
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.
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。
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。
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
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.
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。
In January 2010, at President Obama's request, Bush and Bill Clinton established the Clinton Bush Haiti Fund to raise contributions for relief and recovery efforts after the 2010 Haiti earthquake earlier that month. On May 2, 2011, President Obama called Bush, who was at a restaurant with his wife, to inform him that Osama bin Laden had been killed. The Bushes joined the Obamas in New York City to mark the tenth anniversary of the September 11, 2001, terrorist attacks. At the Ground Zero memorial, Bush read a letter that President Abraham Lincoln wrote to a widow who had lost five sons during the Civil War. On September 7, 2017, Bush partnered with former presidents Jimmy Carter, George H. W. Bush, Bill Clinton, and Barack Obama to work with One America Appeal to help the victims of Hurricane Harvey and Hurricane Irma in the Gulf Coast and Texas communities. Over the years, President Bush has had a good-natured friendship with Michelle Obama. "President Bush and I, we are forever seatmates because of protocol, and that's how we sit at all the official functions," Obama told the Today Show. "He's my partner in crime at every major thing where all the 'formers' gather. So we're together all the time." Bush famously passed mints to Obama during the McCain funeral in September 2018 and gave them to her again during the funeral of his father in December 2018.
==== United States ==== Luvesilocin is not an explicitly controlled substance in the United States. However, it could be considered a controlled substance under the Federal Analogue Act if intended for human consumption.
Meanwhile the affected person undergoes myeloablative conditioning, after which the altered HSCs can be infused back, becoming engrafted in the bone marrow where they proliferate. This results in a progressive increase in beta-globin synthesis which improves the balance of alpha and beta globins in all subsequent developing red blood cells. Healthy hemoglobin A is generated resolving the anemia. Exagamglogene autotemcel, sold under the brand name Casgevy, is a gene therapy for the treatment of transfusion-dependent beta thalassemia which induces increased production of fetal hemoglobin HbF. The treatment was approved in the United Kingdom for the treatment of transfusion-dependent beta thalassemia in November 2023 and in the United States in January 2024. Casgevy works by editing the BCL11A gene, which normally inhibits the production of HbF in adults. The edit has the effect of increasing production of gamma globin, a component of fetal hemoglobin HbF, and thereby resolving the anemia.
=== Holter monitor === A Holter monitor records a continuous EKG rhythm pattern (rarely a full EKG) for 24 hours or more. These monitors are used for suspected frequent rhythm abnormalities, especially ones the wearer may not recognize by symptoms. They are more expensive than event monitors.
Sources: en.wikipedia.org
== Oxidants and reductants == Oxidizing agents are added to flour to help with gluten development. They may or may not also act as bleaching agents. Originally flour was naturally aged through exposure to the atmosphere. Oxidizing agents primarily affect sulfur-containing amino acids, ultimately helping to form disulfide bridges between the gluten molecules. The addition of these agents to flour will create a stronger dough. Dehydroascorbic acid and potassium bromate are oxidants, acting on sulfhydryl groups and disulfide bonds in wheat dough, in particular oxidizing glutathione. Potassium bromate acts more directly or with fewer chemical conversion steps than ascorbic acid. Glutathione increases wheat dough's extensibility, or relaxes it, while oxidizing a dough's glutathione increases elasticity. Common oxidizing agents are:
=== Diagnostic use === Immunohistochemistry using antibodies to ubiquitin can identify abnormal accumulations of this protein inside cells, indicating a disease process. These protein accumulations are referred to as inclusion bodies (which is a general term for any microscopically visible collection of abnormal material in a cell). Examples include:
The South Atlantic plant was built in 1987 in Charleston, SC. At 1,500,000 cubic feet (42,000 m3), this facility can blast freeze up to 320,000 lbs of meat and poultry a day. There are 16 truck platforms and the warehouse is accessible to all railroads that serve Charleston, SC (Norfolk Southern and CSX directly). This facility is certified for Russian meat and poultry shipments.
It is commonly believed that during the Middle Ages, pepper was often used to conceal the taste of partially rotten meat. No evidence supports this claim, and historians view it as highly unlikely; in the Middle Ages, pepper was a luxury item, affordable only to the wealthy, who certainly had unspoiled meat available, as well. In addition, people of the time certainly knew that eating spoiled food would make them sick. Similarly, the belief that pepper was widely used as a preservative is questionable; it is true that piperine, the compound that gives pepper its spiciness, has some antimicrobial properties, but at the concentrations present when pepper is used as a spice, the effect is small. Salt is a much more effective preservative, and salt-cured meats were common fare, especially in winter. However, pepper and other spices played a role in improving the taste of long-preserved meats. Archaeological evidence of pepper consumption in late medieval Northern Europe comes from excavations on the Danish-Norwegian flagship, Gribshunden, which sank in the summer of 1495. In 2021, archaeologists recovered more than 2,000 peppercorns from the wreck, along with a variety of other spices and exotic foodstuffs including clove, ginger, saffron, and almond. The ship was carrying King Hans to a political summit at the time of its loss. The spices were likely intended for feasts at the summit, which would have included the Danish, Norwegian, and Swedish Councils of State.
Criminologist Jane Monkton-Smith said it was particularly unusual that Norris didn't behave as if he wanted to defend himself in interviews, but instead challenged the police and acted evasively. Norris later admitted that he was trying to show how much more he knew than the police in interviews. In 2004, during the investigation, he walked into the offices of the Yorkshire Evening Post and declared that the police had "nothing on him" to reporters. Chief superintendent on the case Chris Gregg claimed that Norris's prediction of Hall's illness showed that it wasn't just a spontaneous incident where a criminal nurse at work had, for whatever reason decided to kill someone, saying "he actually premeditated this, hours before". Gregg said: "I think he was cocky; I think he was over-confident. He was showing off". A criminal psychologist stated that, despite Norris's prediction, it was unlikely that he wanted to get caught, rather that he merely wanted to demonstrate a sense of superior knowledge. Police noted that, in interviews, Norris showed no empathy for the women who had died or for their families, and claimed he couldn't remember any of the women.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
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。