Everything below concerns N-acetyl Semax. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-12-29. Numbers and descriptions here follow the published literature rather than marketing material.
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。
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。
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.
| Property | Value | Notes |
|---|---|---|
| 外观 | 白色至类白色粉末 | 常见于冻干制剂 |
| 溶解度 | 易溶于水 | 在极性溶剂中一般也可溶 |
| 建议储存温度 | -20 °C | 冻干粉,避光密封 |
| 常见分析手段 | 反相高效液相色谱 | 常与质谱联用 |
| 主要降解路径 | 水解与氧化 | 溶液状态更显著 |
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。
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.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
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.
In 1927, fossils of an ancient wild species of cow, Hanaizumi Moriushi (Leptobison hanaizumiensis), dating from the Paleolithic period about 20,000 years ago, were discovered at the Hanaizumi Site in Ichinoseki City, Iwate Prefecture. The Hanaizumi Moriushi is a species similar to the bison and is said to be close to the steppe bison (Bison priscus) lineage. Fossil bones of Aurochs (Bos primigenius) have also been found in Ichinoseki City. Since Hokkaido and Honshu were land-locked with the Eurasian continent during the Ice Age, these animals came from the continent via Hokkaido. In addition, projectile points made from polished wild cattle bones have been found at the same site, although in small quantities, suggesting that humans existed during this period and that Hanaizumi Moriushi and aurochs were hunted. At the Ohama Site in Goto City, Nagasaki Prefecture, cattle teeth dating to the middle Yayoi period were excavated. Among them were also processed cattle molars. However, this excavation was controversial because it contradicted the statement in Chen Shou's Records of the Three Kingdoms (Wajinden) that there were no cattle or horses in Japan. Later, radiocarbon dating of the excavated cattle molars yielded a date of around 40 AD (±90 years).
== Genes == The gene for the alpha subunit is located on chromosome 6q12.21. The luteinizing hormone beta subunit gene is localized in the LHB/CGB gene cluster on chromosome 19q13.32. In contrast to the alpha gene activity, beta LH subunit gene activity is restricted to the pituitary gonadotropic cells. It is regulated by the gonadotropin-releasing hormone from the hypothalamus. GnRH activates Egr1 which interacts with transcription factors NR5A1 and PITX1 at the gene promoter to up-regulate LHB transcription.
== Degradation mechanism == PLGA degradation is mainly governed by bulk erosion rather than surface erosion, specifically in microspheres and implants. Water penetration throughout the polymer matrix in these systems results in homogeneous hydrolysis of its ester linkages, leading to a progressive decrease in molecular weight before significant loss of mass occurs. It has been shown that the time required for degradation of PLGA is related to the monomers' ratio used in production: the higher the content of glycolide units, the lower the time required for degradation as compared to predominantly lactide materials. An exception to this rule is the copolymer with 50:50 monomers' ratio which exhibits the faster degradation (about two months). In addition, polymers that are end-capped with esters (as opposed to the free carboxylic acid) demonstrate longer degradation half-lives. This flexibility in degradation has made it convenient for fabrication of many medical devices, such as, grafts, sutures, implants, prosthetic devices, surgical sealant films, micro and nanoparticles. Degradation behavior is also influenced by factors like polymer composition, molecular weight, pH, ionic strength, etc. This process is usually accompanied by the formation of an acidic environment within the polymer matrix due to the accumulation of lactic and glycolic acid degradation products, which can further accelerate autocatalytic degradation. Limited diffusion of acidic byproducts can lead to localized pH gradients and heterogeneous degradation within larger PLGA systems.
=== Depositional environments === Dinosaur eggs are known from a variety of depositional environments. Beach sands: Beach sands were a good place for dinosaurs to lay their eggs because the sand would be effective at absorbing and holding enough heat to incubate the eggs. One ancient beach deposit in northeastern Spain actually preserves about 300,000 fossil dinosaur eggs. Floodplains: Dinosaurs often laid their eggs on ancient floodplains. The mudstones deposited at these sites are therefore excellent sources of dinosaur egg fossils. Sand dunes: Many dinosaur eggs have been recovered from sandstone deposits that formed in the ancient dune fields of what are now northern China and Mongolia. The presence of Oviraptor preserved in their life brooding position suggests that the eggs, nests, and parents may have been rapidly buried by sandstorms.
Sources: en.wikipedia.org
== Overdose == Enobosarm has been assessed in clinical trials at doses ranging from 0.1 to 18 mg/day. However, most research has been done at doses of 0.1 to 3 mg/day, with two phase 3 clinical trials using a dosage of 3 mg/day. A few small phase 1 and phase 2 trials of enobosarm for breast cancer have employed doses of 9 to 18 mg/day. Larger, phase 3 trials of enobosarm at a dose of 9 mg/day for breast cancer (e.g., ARTEST, n=210) are now underway. Doses of up to 100 mg have been assessed in single-dose pharmacokinetic studies and doses of up to 30 mg/day have been given in short 14-day pharmacokinetic studies. Enobosarm sold via black-market Internet suppliers and used non-medically is often taken at much higher doses than those used widely in clinical trials (e.g., 10–30 mg/day), with unknown adverse effects and risks.
The organization of solvent systems into "families" has greatly facilitated the choice of solvent systems as well. A solvent system can be tested with a one-flask partitioning experiment. The measured partition coefficient from the partitioning experiment will indicate the elution behavior of the compound. Typically, it is desirable to choose a solvent system where the target compound(s) have a partition coefficient between 0.25 and 8. Historically, it was thought that no commercial countercurrent chromatograph could cope with the high viscosities of ionic liquids. However, modern instruments that can accommodate 30 to 70+ % ionic liquids (and potentially 100% ionic liquid, if both phases are suitably customized ionic liquids) have become available. Ionic liquids can be customized for polar / non-polar organic, achiral and chiral compounds, bio-molecule, and inorganic separations, as ionic liquids can be customized to have extraordinary solvency and specificity. After the biphasic solvent system has been chosen a batch of is formulated and equilibrated in a separatory funnel. This step is called pre-equilibration of the solvent system. The two phases are separated. Then the column is filled with stationary with a pump. Next, the column is set an equilibration conditions, such as the desired rotation speed, and the mobile phase is pumped through the column. The mobile phase displaces the a portion of the stationary phase until column equilibration is achieved and the mobile phase elutes from the column.
DD-Transpeptidase (EC 3.4.16.4, DD-peptidase, DD-transpeptidase, DD-carboxypeptidase, D-alanyl-D-alanine carboxypeptidase, D-alanyl-D-alanine-cleaving-peptidase, D-alanine carboxypeptidase, D-alanyl carboxypeptidase, and serine-type D-Ala-D-Ala carboxypeptidase.) is a bacterial enzyme that catalyzes the transfer of the R-L-αα-D-alanyl moiety of R-L-αα-D-alanyl-D-alanine carbonyl donors to the γ-OH of their active-site serine and from this to a final acceptor. It is involved in bacterial cell wall biosynthesis, namely, the transpeptidation that crosslinks the peptide side chains of peptidoglycan strands. The antibiotic penicillin irreversibly binds to and inhibits the activity of the transpeptidase enzyme by forming a highly stable penicilloyl-enzyme intermediate. Because of the interaction between penicillin and transpeptidase, this enzyme is also known as penicillin-binding protein (PBP).
Sources: en.wikipedia.org
Apples grown for consumption are suitable for cider making, though some regional cider-makers prefer to use a mix of eating and cider apples (as in Kent, England), or exclusively cider apples (as in the West Country, England and West of England). There are many hundreds of varieties of cultivars developed specifically for cider making.
=== Multiwell plate === Multiwell plates are multiple petri dishes incorporated into one container, with the number of individual wells ranging from 6 to over 1536. Multiwell Plate Assays are convenient for handling necessary dosages and replicates. There are a wide range of plate types that have a standardized footprint, supporting equipment, and measurement systems. Electrodes can be integrated into the bottom of the plates to capture information as a result of the binding assays. The binding reagents become immobilized on the electrode surface and then can be analyzed. The multiwell plates are manufactured to allow researchers to create and manipulate different types of assays (i.e., bioassays, immunoassays, etc.) within each multiwell plate. Due to the variability in multiwell plate formatting, it is not uncommon for artifacts to arise. Artifacts are due to the different environments found within the different wells on the plate, especially near the edges and center of the wells. Such effects are known as well effects, edge effects, and plate effects. Thus, emphasizing the necessity to position assay designs in the correct manner both within, and between, each plate. The use of multiwell plates are common when measuring in vitro biological assay activity, or measuring immunoreactivity through immunoassays. Artifacts can be avoided by maintaining plate uniformity by applying the same dose of the specific medium in each well, in addition to maintaining atmospheric pressure and temperature rates in order to reduce humidity.
=== Sniper: Rogue Mission (2022) === After discovering a human sex trafficking ring working with a corrupt agent, Brandon Beckett teams up with allies from his past, Agent Zeke "Zero" Rosenberg and Yuki "Lady Death" Mifune, to discover the identity of the agent and stop the ring.
== Embryonic development == During embryo development in mice, CCN1 is highly expressed in the cardiovascular, skeletal, and neuronal systems. CCN1 knockout mice are embryonic lethal due to defects in cardiac septal morphogenesis, deficient blood vessel formation in placenta, and compromised vascular integrity. In Xenopus laevis, CCN1 is required for normal gastrulation and modulation of Wnt signaling.
Sources: en.wikipedia.org
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受,但会加快降解风险。
公开资料对此没有统一答案。普遍建议现配现用,或冷藏并在数日内用完。含甲硫氨酸的序列更易氧化,放置时间越长风险越高。
反相高效液相色谱是最常用的手段,配合质谱确认分子量。氨基酸组成分析和肽图分析可补充序列层面的验证。
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.