nasal formulation raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-07-18. Anything still debated is marked as such rather than presented as settled.
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。
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。
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
| 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 |
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
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.
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.
Curran TW, Lawrence DN, Jaffe HS, Kaplan JE, Zyla LD, Chamberland M, Weinstein R, Lui KJ, Schonberger LB, Spira TJ, Alexander WJ, Swinger G, Ammann AJ, Solomon S, Auerbach D, Mildvan D, Stoneburner R, Jason JM, Haverkos HW, Evat BL. Acquired immunodeficiency associated with transfusions. NEJM, 310:69-75, 1984. Cowan MJ, Hellmann D, Chudwin D, Wara DW, Chang RS, Ammann AJ. Maternal transmission of acquired immune deficiency syndrome. Pediat, 73:382-386, 1984. Cao Y, Krogstad P, Korber BT, Koup RA, Muldoon M, Macken C, Song J-L, Jin Z, Zhao J-Q, Clapp S, Chen ISY, Ho DD., Ammann AJ and the Ariel Project Investigators. Maternal HIV-1 viral load and vertical transmission of infection: The Ariel Project for the prevention of HIV transmission from mother to infant. Nature Medicine 3: 549-552 1997. Ammann AJ. HIV in China: An Opportunity to Halt an Emerging Epidemic. Ammann AJ AIDS Patient Care and STDs 14:109-112, 2000. Ammann AJ. Introduction to the Second Conference on Global Strategies for the Prevention of HIV Transmission from Mothers to Infants. Annals NY Academy of Sciences 918:1-2, 2000. Kim JY, Ammann AJ. Is the "3 by 5" initiative the best approach to tackling the HIV pandemic? PLoS Med. 2004 Nov;1(2):e37. Epub 2004 Nov 30. Ammann AJ. Feminization of the HIV Epidemic. Radix 32:8-13 2006 Ammann AJ. Advances in HIV Care and Treatment in Resource Poor Countries. HIV Therapy. 2009 3:329-338.
=== Amphetamines === Amphetamines are a chemical class of stimulants, entactogens, hallucinogens, and other drugs. They feature a phenethylamine core with a methyl group attached to the alpha carbon resulting in amphetamine, along with additional substitutions.
== Complications == The plastic surgical emplacement of breast implant devices, either for breast reconstruction or for aesthetic purpose, presents the same health risks common to surgery, such as adverse reaction to anesthesia, hematoma (post-operative bleeding), late hematoma (post-operative bleeding after 6 months or more), seroma (fluid accumulation), incision-site breakdown (wound infection). Complications specific to breast augmentation include breast pain, altered sensation, impeded breast-feeding function, visible wrinkling, asymmetry, thinning of the breast tissue, and symmastia, the "bread loafing" of the bust that interrupts the natural plane between the breasts. Specific treatments for the complications of indwelling breast implants—capsular contracture and capsular rupture—are periodic MRI monitoring and physical examinations. Furthermore, complications and re-operations related to the implantation surgery, and to tissue expanders (implant place-holders during surgery) can cause unfavorable scarring in approximately 6–7 percent of the patients. Statistically, 20 percent of women who underwent cosmetic implantation, and 50 percent of women who underwent breast reconstruction implantation, required their explantation (surgical removal) at the 10-year mark.
To be a Royal Arch Purpleman, one must be a professing reformed Christian, sober and temperate, not prone to cursing or swearing, and a faithful attender in his Church. Marksman for example within the Royal Arch Purple refers to the Israelites who marked the location of the Ark of the Covenant. The Royal Arch Purple Degree is now established as a separate Order, in Ireland at least, and has over 30,000 members. The collarette of a Royal Arch Purpleman is a collarette of Orange and Purple in which the colour purple predominates. The Royal Arch Purple Degree is now established as a separate Order and is widely practised as a natural step of advancement from the Orange Institution to the Royal Black Institution.
Sources: en.wikipedia.org
== Applications == Synthetic antibodies have shown their utility in a number of applications. Their use within the field of research lies predominantly in the life sciences as reagents for protein capture and as protein inhibitors. Within diagnostics they have been utilised in applications ranging from infection and cancer screening to mycotoxin detection in grain samples. Synthetic antibodies are currently the fastest growing class of therapeutics.
"...and much more likely to endure their miseries publicly; a tired walker, after all, merely sits down – a tired cyclist falls off and possibly brings others crashing down as well. That's much more fun". The fascination with six-day bicycle races spread across the Atlantic and appealed to the crowds in America as well. And the more spectators paid at the gate, the higher the prizes could be and the greater was the incentive of riders to stay awake—or be kept awake—to ride the greatest distance. Their exhaustion was countered by soigneurs (the French word for "healers"), helpers akin to seconds in boxing. Among the treatments they supplied was nitroglycerine, a drug used to stimulate the heart after cardiac attacks and which was credited with improving riders' breathing. Riders had hallucinations from the exhaustion and perhaps the drugs. The American champion Major Taylor refused to continue the New York race, saying: "I cannot go on with safety, for there is a man chasing me around the ring with a knife in his hand." Public reaction turned against such trials, whether individual races or in teams of two. One report said:
== Diagnosis == Substance use disorders can be confused with other psychiatric disorders. There are diagnoses for substance-induced mood disorders and substance-induced anxiety disorders and thus such overlap can be complicated. For this reason, the DSM-IV advises that diagnoses of primary psychiatric disorders not be made in the absence of sobriety (of a duration sufficient to allow for any substance-induced post-acute-withdrawal symptoms to dissipate) up to 1 year.
Sources: en.wikipedia.org
== Chemistry == Tofu is made from soy milk which is a turbid colloid liquid/solution. Tofu structure is related to soy milk components, particularly colloid components such as protein particles and oil globules. Protein particle content increases with the increase of the globulin ratio in the soybeans. Tofu varieties ensue from adding coagulants at various concentrations.
== Return to competition == In 1988, the IOC formed the Apartheid and Olympism Commission, including Kevan Gosper, the SCSA, and SANROC. While SANOC agreed it could not seek readmission to the IOC until apartheid was dismantled, negotiations to prepare the way for South Africa's reintegration into world sport proceeded in tandem with the political negotiations to end apartheid. Within South Africa, in each sport there were competing race-specific and multi-racial bodies, which would have to merge into one in order to affiliate into both a nonracial NOC and the IF for its sport. ANOCA took the lead in negotiations in 1990 and 1991, and an Interim National Olympic Committee of South Africa (INOCSA) was formed with Sam Ramsamy as president. Ramsamy had been a leading anti-apartheid campaigner and advocate of sports boycotts. In June 1991, the Population Registration Act, 1950, a cornerstone of apartheid legislation, was repealed by the government of F. W. de Klerk, and in July an INOCSA delegation met with the Apartheid and Olympism Commission at the IOC headquarters in Lausanne. The IOC recognised INOCSA on 9 July 1991, such that the "interim" was removed from its name (NOCSA). It first competed at the 1992 Summer Olympics in Barcelona. The official flag of South Africa and national anthem "Die Stem van Suid-Afrika" were still the apartheid-era ones, but the Olympic team competed under an interim flag and Ludwig van Beethoven's "Ode to Joy". Likewise it decided not to use the Springbok emblem or green-and-gold colours of white sports teams.
transfer RNA (tRNA) Formerly referred to as soluble RNA (sRNA). A special class of RNA molecule, typically 76 to 90 nucleotides in length, that serves as a physical adapter allowing mRNA transcripts to be translated into sequences of amino acids during protein synthesis. Each tRNA contains a specific anticodon triplet corresponding to an amino acid that is covalently attached to the tRNA's opposite end; as translation proceeds, tRNAs are recruited to the ribosome, where each mRNA codon is paired with a tRNA containing the complementary anticodon. Depending on the organism, cells may employ as many as 41 distinct tRNAs with unique anticodons; because of codon degeneracy within the genetic code, several tRNAs containing different anticodons carry the same amino acid.
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。
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.