The short version of 甲硫氨酸氧化 fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-10-08. Anything still debated is marked as such rather than presented as settled.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
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 mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
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。
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。
Here, ethylene oxide is obtained as the overhead product, whereas the bottom product obtained is known as the glycol bleed. When ethylene oxide is scrubbed from the recycle gas with an aqueous solution, ethylene glycols (viz. mono-ethylene glycol, di-ethylene glycol and other poly-ethylene glycols) get unavoidably produced. Thus, in-order to prevent them from building up in the system, they are continuously bled off. Stripping and distillation column: Here, the ethylene oxide stream is stripped off its low boiling components and then distilled in-order to separate it into water and ethylene oxide. CO2 scrubber: The recycle stream obtained from the ethylene oxide scrubber is compressed and a side-stream is fed to the CO2 scrubber. Here, CO2 gets dissolved into the hot aqueous solution of potassium carbonate (i.e., the scrubbing media). The dissolution of CO2 is not only a physical phenomenon, but a chemical phenomenon as well, for, the CO2 reacts with potassium carbonate to produce potassium hydrogen carbonate.
Maurice Glasman, Baron Glasman (born 8 March 1961) prolific author, political theorist, academic, social commentator, and Labour life peer in the House of Lords; senior lecturer in Political Theory at London Metropolitan University and Director of its Faith and Citizenship Programme; best known as a founder of Blue Labour, a term he coined in 2009;called on the Labour Party to establish dialogue with the far-right English Defence League (EDL) in order to challenge their views; called for some immigration to be temporarily halted and for the right of free movement of labour, a key provision of the Treaty of Rome, to be abrogated, dividing opinion among Labour commentators.; accepted the visiting professorship he was offered by Haifa University, telling The Jewish Chronicle: "If people I know say they want to boycott Israel, I say they should start by boycotting me". At the 2016 Limmud conference, he suggested the Labour Party's antisemitism harked back to Jewish Marxists, who wanted to "liberate Jews" from their Judaism. Ralph Glasser wrote Growing up in the Gorbals Donny Gluckstein (b. 1954); historian at Edinburgh College; son of Tony Cliff and Chanie Rosenberg, is author of numerous books and articles; his book A People's History of the Second World War shortlisted for the Bread and Roses Award.
== Function == The function galectin-7 has recently been found to be a critical role in is with skin tissue linking to skin cancers because of its involvement with apoptosis from the LGALS7 gene that the protein is produced from, though it still is involved with the oral cavity, esophagus, epidermis, and cornea, with skin cancer being the most notable one. During skin repair, cell migration is the process by which cells close a wound which includes the epidermal keratinocytes migration which re-established the skin barrier, re-epithelialization. The protein's involvement, if deficient, can result in a defect of cell migration leading to less proficient skin repair as well. Re-epithelialization, skin repair, the regulation of cell migration, and cell adhesion is also expressed within skin tumors and still needs to be better researched as its abnormal expression in carcinomas, cancer progression, and metastasis is still not understood in terms of its function. While the protein's function in the nucleus is still unknown, the diverse studies for the cellular function in mitochondria and cytosol link pathways to regulation of keratinocyte and differentiation while also having a mutation bind to a hot spot called the galectin-7 promoter. Galectin-7 regulates cell growth, cell differentiation, and apoptosis in epithelial maintenance roles but there are still many unknowns when it comes to this protein in its role of cellular processes.
Sources: en.wikipedia.org
Bilberry (), also known as European blueberry, is a Eurasian low-growing shrub in the genus Vaccinium of the flowering plant family Ericaceae. Vaccinium myrtillus L. is the species most commonly called bilberry, but other closely related Vaccinium species may also have this name. Bilberries, which are native to Europe, are different from North American blueberries, although the species are closely related and belong to the same genus, Vaccinium; they produce edible, dark blue berries. The dark blue colour of bilberries derives from the high content of anthocyanins. Well known in folklore, bilberry extracts and dried powders are sold as dietary supplements promoted mainly for eye disorders, although there is no substantial clinical evidence that consuming bilberry fruit or its preparations provides any health benefits.
Troponin C binds to calcium ions (Ca2+) to produce a conformational change in TnI Troponin T binds to tropomyosin, interlocking them to form a troponin-tropomyosin complex with thin filaments Troponin I binds to actin in thin myofilaments to hold the actin-tropomyosin complex in place. It inhibits the ATPase activise of actomyosin. Inside the cardiac troponin complex, the strongest interaction between molecules is the cTnI–TnC binary complex, especially in the presence of Ca2+ (KA = 1.5 × 10−8 M−1). TnC, forming a complex with cTnI, changes the conformation of cTnI molecule and shields part of its surface. According to the latest data cTnI is released in the blood stream of the patient in the form of binary complex with TnC or ternary complex with cTnT and TnC. cTnI-TnC complex formation plays an important positive role in improving the stability of cTnI molecule. cTnI, which is extremely unstable in its free form, demonstrates significantly better stability in complex with TnC or in ternary cTnI-cTnT-TnC complex. It has been demonstrated that stability of cTnI in native complex is significantly better than stability of the purified form of the protein or the stability of cTnI in artificial troponin complexes combined from purified proteins.
Japanese centenarians receive a silver cup and a certificate from the prime minister of Japan upon the Respect for the Aged Day following their 100th birthday, honouring them for their longevity and prosperity in their lives. In Madhya Pradesh, India, the award known as Shatayu Samman is given out to people who live at least 100 years to promote awareness of good health. North Korean centenarians receive a birthday congratulatory letter from the Supreme Leader of the DPRK. On 6 July 2022, Pak Hak Sil, a centenarian living in Koup-ri of Kangnam County, Pyongyang, received a birthday letter sent by Kim Jong Un. In the Philippines, Republic Act No. 10868 better known as the Centenarians Act of 2016 mandates that all living Filipinos residing in the Philippines or overseas receive a birthday congratulatory letter from the President of the Philippines and a ₱100,000 "Centenarian Gift" from the Department of Social Welfare and Development (DSWD). In Taiwan, people aged 100 or above receive a golden pendant necklace on Chong Yang Festival each year from the president and Ministry of Health and Welfare. Mahathir Mohamad became the first prime minister of Malaysia to reach the age of 100 on 10 July 2025. His wife, Siti Hasmah, reached the age of 100 on 12 July 2026; before passing away two months later due to heart failure.
Sources: en.wikipedia.org
San Juan Bautista was built in 1613 by Date Masamune, the daimyō of Sendai in northern Japan, in Tsuki-No-Ura harbour (Ishinomaki, Miyagi Prefecture). The project had been approved by the Bakufu, the shōgun's government in Edo. The shōgun already had two smaller ships (80 and 120 tons) built for him by the English pilot William Adams. The larger, the San Buena Ventura, was given to Spanish shipwrecked sailors to return to New Spain in 1610. The shōgun also issued numerous permits for Red seal ships, destined for Asian trade and incorporating many elements of Western ship design. San Juan Bautista is reported to have required 45 days' work, with the participation of technical experts from the Bakufu, 800 shipwrights, 700 smiths, and 3000 carpenters. Two Spanish men also participated to the endeavour: the friar Luis Sotelo, and the Spanish captain Sebastián Vizcaíno. These efforts were seen with disapproval by the Spanish government in Manila, and Los Rios Coronel suggested that Luis Sotelo should not be allowed into Japan any further (C. R. Boxer).
Testing during and for many weeks after a hemolytic episode will lead to false-negative results, as the G6PD-deficient RBC will have been excreted, and the young RBC (reticulocyte) will not yet be G6PD deficient. False-negative results will also be likely following any blood transfusions. For this reason, many hospitals wait three months after a hemolytic episode before testing for G6PD deficiency. Females should have their G6PD activity measured by a quantitative assay to avoid being misclassified by screening tests.
=== Pancreatic and thyroid safety === Historically, GLP-1 receptor agonists have carried warnings regarding acute pancreatitis and pancreatic cancer. However, large-scale cardiovascular outcome trials for semaglutide have not found a statistically significant increase in the incidence of these conditions in humans. The US prescription label contains a boxed warning for thyroid C-cell tumors. This warning is based on rodent studies; rodents possess a high density of GLP-1 receptors in their thyroid C-cells, which leads to hyperplasia and tumors when stimulated. In contrast, human thyroids express these receptors only marginally, making the risk of medullary thyroid carcinoma highly specific to rodents and clinically unlikely in humans. Semaglutide remains contraindicated in individuals with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2.
Sources: en.wikipedia.org
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
Dry powder is normally held at -20 °C or lower, away from light and moisture. Sealed vials can also be kept at 2-8 °C for shorter intervals. Warming to room temperature before opening prevents condensation.