Everything below concerns ACTH fragment. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-07-22. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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。
| 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.
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 the early modern period, successor states to the Adal Sultanate and Ajuran Sultanate began to flourish in Somalia. These included the Hiraab Imamate, the Isaaq Sultanate led by the Guled dynasty, the Habr Yunis Sultanate led by the Ainanshe dynasty, the Sultanate of the Geledi (Gobroon dynasty), the Majeerteen Sultanate (Migiurtinia), and the Sultanate of Hobyo (Obbia). They continued the tradition of castle-building and seaborne trade established by previous Somali empires. Sultan Yusuf Mahamud Ibrahim, the third Sultan of the House of Gobroon, started the golden age of the Gobroon Dynasty. His army came out victorious during the Bardheere Jihad, which restored stability in the region and revitalised the East African ivory trade. He also had cordial relations and received gifts from the rulers of neighbouring and distant kingdoms such as the Omani, Witu and Yemeni Sultans. Sultan Ibrahim's son Ahmed Yusuf succeeded him as one of the most important figures in 19th-century East Africa, receiving tribute from Omani governors and creating alliances with important Muslim families on the East African coast.
Arthrobacter atrocyaneus Arthrobacter crystallopoietes Arthrobacter polychromogones Corynebacterium insidiosum Erwinia chrysanthemi renamed to Dickea dadantii Vogesella indigofera previously Bacillus indigoferus and Pseudomonas indigofera
February 3 – The government shutdown ends with a bill that funds DHS for two weeks. February 4 The Central Intelligence Agency announces it will no longer publish The World Factbook. Decline of newspapers: The Washington Post announces 300 journalist layoffs, roughly one-third of its employees, as part of a major restructuring. February 5 The New START treaty limiting strategic nuclear weapons with Russia expires. Three people are killed and seven others are injured when a car crashes into a 99 Ranch Market in Westwood, Los Angeles, California. February 6 – Trump shares a video on social media depicting Barack and Michelle Obama as apes. Trump receives bipartisan condemnation. February 8 – Super Bowl LX is played at Levi's Stadium in Santa Clara, California, with the Seattle Seahawks prevailing over the New England Patriots. Bad Bunny headlines the halftime show with special guests Lady Gaga and Ricky Martin, while Kid Rock performs at the Turning Point alternate All-American Halftime Show. February 10 – Trump threatens the opening of the Gordie Howe International Bridge, saying the U.S. should be "fully compensated for everything" it has given to Canada, and demanding that Ottawa "treats the United States with the Fairness and Respect that we deserve". February 11 – The Federal Aviation Administration abruptly announces a 10-day temporary flight restriction (TFR) over El Paso, Texas and surrounding areas (specifically a 10-mile radius surrounding El Paso International Airport).
== Further reading == Brown, T. L.; Bursten, B. E.; LeMay, H. E. (2006). J. Challice; N. Folchetti (eds.). Chemistry: The Central Science (10th ed.). Pearson Education. pp. 276& 289. ISBN 978-0-13-109686-8. Lide, D. R. (2005). "Properties of the Elements and Inorganic Compounds; Melting, boiling, triple, and critical temperatures of the elements". CRC Handbook of Chemistry and Physics (86th ed.). CRC Press. §4. ISBN 978-0-8493-0486-6. On triple point pressure at 69 kPa. Preston-Thomas, H. (1990). "The International Temperature Scale of 1990 (ITS-90)". Metrologia. 27 (1): 3–10. Bibcode:1990Metro..27....3P. doi:10.1088/0026-1394/27/1/002. S2CID 250785635. On triple point pressure at 83.8058 K.
Sources: en.wikipedia.org
Backup process monitoring: Enterprise client-server backup applications need a user interface that allows administrators to monitor the backup process, and proves compliance to regulatory bodies outside the organization; for example, an insurance company in the USA might be required under HIPAA to demonstrate that its client data meet records retention requirements. User-initiated backups and restores: To avoid or recover from minor disasters, such as inadvertently deleting or overwriting the "good" versions of one or more files, the computer user—rather than an administrator—may initiate backups and restores (from not necessarily the most-recent backup) of files or folders.
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functional groups in solid, liquid, or gaseous forms. It can be used to characterize new materials or identify and verify known and unknown samples. The method or technique of infrared spectroscopy is conducted with an instrument called an infrared spectrometer (or spectrophotometer) which produces an infrared spectrum. An IR spectrum can be visualized in a graph of infrared light absorbance (or transmittance) on the vertical axis vs. frequency, wavenumber or wavelength on the horizontal axis. Typical units of wavenumber used in IR spectra are reciprocal centimeters, with the symbol cm−1. Units of IR wavelength are commonly given in micrometers (formerly called "microns"), symbol μm, which are related to the wavenumber in a reciprocal way. A common laboratory instrument that uses this technique is a Fourier transform infrared (FTIR) spectrometer. Two-dimensional IR is also possible as discussed below. The infrared portion of the electromagnetic spectrum is usually divided into three regions; the near-, mid- and far- infrared, named for their relation to the visible spectrum. The higher-energy near-IR, approximately 14,000–4,000 cm−1 (0.7–2.5 μm wavelength) can excite overtone or combination modes of molecular vibrations.
=== Ga–Gl === Johan Gadolin (1760–1852), Finnish chemist who discvered yttrium Joseph Louis Gay-Lussac (1778–1850), French chemist and physicist who discovered the Gay-Lussac law, known for discovering that water is made of two parts hydrogen and one part oxygen by volume Charles Frédéric Gerhardt (1816–1856), French chemist known for reforming the notation for chemical formulas, and for synthesizing acetylsalicylic acid (aspirin) Jnan Chandra Ghosh (1894–1959), Indian chemist known for research on strong electrolytes and the dissociation--ionization theory William Giauque (1895–1982), 1949 Nobel Prize in Chemistry for studies of the properties of matter at temperatures close to absolute zero Josiah Willard Gibbs (1839–1903), American chemist and physicist whose work on thermodynamics helped to transform physical chemistry into a rigorous deductive science Walter Gilbert (born 1932), 1980 Nobel Prize in Chemistry for a method of sequencing nucleic acids Cornelia Gillyard (born 1941), American organic chemist known for work with chemicals in the environment Henry Gilman (1893–1986), American chemist who developed organometallic chemistry, and discovered the Gilman reagent Judith Giordan (Thesis 1980), American chemist who worked on unsaturated hydrocarbons and became President-Elect of the American Chemical Society Johann Rudolf Glauber (1604–1670), Dutch-German alchemist and chemist who discovered sodium sulfate and wrote many books Lawrence E. Glendenin (1918–2008), American chemist, co-discovered the element promethium
Hard tissue, referring to "normal" calcified tissue, is tissue which is mineralized and has a firm intercellular matrix. The hard tissues of humans are bone, tooth enamel, dentin, and cementum. The term is in contrast to soft tissue.
The serial analyses of beta thalassemic mice indicate that hemoglobin levels decrease over time, while the concentration of iron in the liver, spleen, and kidneys increases significantly. The overload of iron is associated with low levels of hepcidin. Patients with beta thalassemia also have low hepcidin levels. The observations led researchers to hypothesize that more iron is absorbed in beta thalassemia than is required for erythropoiesis. Increasing expression of hepcidin in beta thalassemic mice limits iron overload, and also decreases formation of insoluble membrane-bound globins and reactive oxygen species, and improves anemia. Mice with increased hepcidin expression also demonstrated an increase in the lifespan of their red cells, reversal of ineffective erythropoiesis and splenomegaly, and an increase in total hemoglobin levels. From these data, researchers suggested that therapeutics to increase hepcidin levels or act as hepcidin agonists could help treat the abnormal iron absorption in individuals with beta thalassemia and related disorders. In later studies with mice, erythroferrone has been suggested to be the factor that is responsible for the hepcidin suppression. Correcting hepcidin and iron levels in these mice did not improve their anemia.
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。