heptapeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-12-28. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
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.
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.
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.
==== Underaged and pregnant offenders ==== Persons under the age of 18 at the time of their offence and pregnant women cannot be sentenced to death. Previously, offenders under 18 at the time of their offences would be indefinitely detained at the president's pleasure (TPP), with the normal period of detention having been between 10 and 20 years. These inmates would be released after receiving clemency from the President of Singapore, once they were assessed to be suitable for release. In 2010, the law was amended to allow judges to hand down a life imprisonment to offenders convicted of capital offences, but aged below 18 at the time of their crimes. They would be required to serve a minimum of 20 years before they can be reviewed for possible release. As for women who were pregnant at the time of their sentencing, they would automatically be sentenced to life imprisonment upon their conviction of any capital offences, though there have been no such cases as of yet. The first underaged offender to be sentenced to life imprisonment after the abolition of TPP was Myanmar national Zin Mar Nwe, a domestic worker who killed the mother-in-law of her employer in June 2018 at the age of 17. She received a life sentence in July 2023 after the High Court found her guilty of murder, with the trial judge Andre Maniam accepting that Zin was a minor and below 18 years of age when killing the 70-year-old victim and he thus opted to not impose a death sentence in her case.
Some cases of melanoma, such as early, surface-level melanoma (lentigo maligna) or thin invasive melanoma, can be treated with Mohs surgery. This is especially considered in areas where tissue sparing is essential. In these cases, special immunohistochemical staining is used to visualize the melanoma cells, evaluate the margins, and ensure the cancer has been completely removed. More evidence today is linking Mohs surgery with lower recurrence rates of melanoma in these cases. This approach is also used in treating rare skin cancers. For example, dermatofibrosarcoma protuberans, a slow-growing cancer that begins in the deeper layers of the skin, as well as cancers arising from hair follicles, oil glands, or sweat glands, would benefit from Mohs surgery as these are cases where margin clearance is essential. In summary, the Mohs micrographic surgery criteria are as follows:
=== Light === Herbarium specimens are sensitive to visible light and ultraviolet radiation, which can cause fading of biological pigments (fading or shifts in color) and/or damage to chemical bonds (weakened or embrittled).
This sheath could also play an important role in reducing the damage to Osedax skin by absorbing harmful acid. Another potential function of the mucus sheath is that it could inhibit the breakdown of the worm's bone matrix. This is significant because the bone matrix is integral in maintaining the worm's position while in direct contact with a bone.
Sources: en.wikipedia.org
=== Intestinal dialysis === In healthy humans, the intestines both remove uremic toxins (urea, creatine, uric acid) from blood and add uremic toxins (indoxyl sulfate, ammonia, etc.) to blood. More uremic toxins are excreted through the gut (as feces) than through the kidneys (as urine). This exchange of substances is enabled by the massive surface area of the intestinal capillary network and intestinal mucus, together serving as a large semipermeable membrane. In patients with kidney failure, the intestines receive a larger influx of uremic toxins due to a higher concentration in blood, but this does not automatically translate to a benefit in reducing blood toxin levels as gut bacteria use these toxins as food, producing more toxins in the process. The goal of intestinal dialysis is to maximize the removal of uremic toxins into the intestines while minimizing the production of new toxin molecules in the intestines. It serves as a more conservative renal replacement therapy for those unable to tolerate conventional dialysis. There are a few forms of intestinal dialysis:
On 18 January 2024, Natalia Kanem, the executive director of the UN Population Fund, spoke at the World Economic Forum at Davos, stating the situation was the "worst nightmare" the UNPF representative had ever witnessed, as there were 180 women giving birth daily, sometimes on the streets of Gaza, as the territory's health system collapsed. On 17 January, Care International reported a 300 percent increase in the rate of miscarriage in Gaza since the start of Israel's bombing. UNICEF reported on 19 January that 20,000 babies had been born in the Gaza Strip since 7 October. UNICEF described each birth as a baby being "delivered into hell", and stated "humanity cannot allow this warped version of normal to persist any longer." The UN Women's agency reported that since the start of the conflict, two mothers in Gaza had been killed every hour, every day. WHO reported an increase in stress-induced stillbirths. Doctors Without Borders stated that women were giving birth in plastic tents, and that those undergoing C-sections were being released within hours. It also reported that women were being turned away from hospitals due to overcrowding, with some forced to birth in public restrooms. Doctors at Kamal Adwan Hospital performed an emergency c-section on a deceased pregnant woman in February 2024, after which they performed a fetal cardiac resuscitation; however, the baby did not survive.
There are a few slightly more common diagnoses such as pulmonary hypoplasia, cryptorchidism, congenital heart defects, tracheoesophageal fistulas, inguinal hernias, cleft palate, and eye abnormalities.
Immediate untreated crush syndrome death is caused by severe head injury, torso injury with damaged abdominal organs, and asphyxia (excessive loss of oxygen). Early untreated crush syndrome death is caused by hyperkalemia and by hypovolemic shock. Late untreated crush syndrome death is caused by renal failure, coagulopathy and hemorrhage, and sepsis. Due to the risk of crush syndrome, current recommendation to nonprofessional first-aiders (in the UK) is to not release those with a crush injury who have been trapped for more than 15 minutes. A torniquet may be used in the event that treatment is not immediately available, as it traps toxins in the ischemic limb, but it is only a method of postponing medical attention. Upon release, isotonic saline is used for fluid resuscitation.
Constitutionally, the Soviet Union was a federation. In accordance with provisions present in its Constitution (versions adopted in 1924, 1936 and 1977), each republic retained the right to secede from the USSR. Throughout the Cold War, this right was widely considered to be meaningless; however, the corresponding Article 72 of the 1977 Constitution was used in December 1991 to effectively dissolve the Soviet Union, when Russia, Ukraine, and Belarus seceded from the Union. Although the Union was created under an initial ideological appearance of forming a supranational union, it never de facto functioned as one; an example of the ambiguity is that the Ukrainian Soviet Socialist Republic in the 1930s officially had its own foreign minister, but that office did not exercise any true sovereignty apart from that of the union. The Constitution of the Soviet Union in its various iterations defined the union as a federation with the right of the republics to secede. This constitutional status led to the possibility of the parade of sovereignties once the republic with de facto (albeit not de jure) dominance over the other republics, the Russian one, developed a prevailing political notion asserting that it would be better off if it seceded. The de facto dominance of the Russian republic is the reason that various historians (for example, Dmitri Volkogonov and others) have asserted that the union was a unitary state in fact albeit not in law.
Sources: en.wikipedia.org
== Prognosis == G6PD-deficient individuals do not appear to acquire any illnesses more frequently than other people, and may have less risk than other people for acquiring ischemic heart disease and cerebrovascular disease. However, a recent study revealed that G6PD deficiency increases cardiovascular risk by up to 70%. The risk conferred by G6PD deficiency is moderate compared with the impact of primary cardiovascular risk factors. Besides, a published review hypothesized that G6PD deficiency could reduce the antiplatelet efficacy of clopidogrel (clopidogrel resistance).
=== European Union === In the European Union, semaglutide is indicated for the treatment of adults with insufficiently controlled type 2 diabetes as an adjunct to diet and exercise as monotherapy when metformin is considered inappropriate due to intolerance or contraindications, in addition to other medicinal products for the treatment of diabetes. Semaglutide (as Wegovy) is further indicated as an adjunct to a reduced-calorie diet and increased physical activity for weight management, including weight loss and weight maintenance, in adults with obesity (initial BMI ≥ 30 kg/m2) or who are overweight (initial BMI ≥ 27 kg/m2) and have at least one weight-related comorbidity such as dysglycemia (prediabetes or type 2 diabetes), hypertension, dyslipidemia, or cardiovascular disease. It is also indicated as an adjunct to a reduced-calorie diet and increased physical activity for weight management in adolescents (aged twelve years and older) with obesity and body weight above 60 kg (130 lb). Semaglutide (as Kayshild) is indicated in conjunction with diet and exercise for the treatment of adults with non-cirrhotic metabolic dysfunction-associated steatohepatitis (MASH) with moderate or advanced liver fibrosis (stage F2 or F3).
According to generally accepted cosmology theory, only isotopes of hydrogen and helium, traces of some isotopes of lithium and beryllium, and perhaps some boron, were created at the Big Bang, while all other nuclides were synthesized later, in stars and supernovae, and in interactions between energetic particles such as cosmic rays, and previously produced nuclides. (See nucleosynthesis for details of the various processes thought responsible for isotope production.) The respective abundances of isotopes on Earth result from the quantities formed by these processes, their spread through the galaxy, and the rates of decay for isotopes that are unstable. After the initial coalescence of the Solar System, isotopes were redistributed according to mass, and the isotopic composition of elements varies slightly from planet to planet. This sometimes makes it possible to trace the origin of meteorites.
== Overdose == Gastric decontamination measures such as activated charcoal are sometimes recommended in cases of overdose. The symptoms are usually indicative of CNS depression (or conversely CNS stimulation in some) and excess anticholinergic side effects. The LD50 in mice is 123 mg/kg and 295 mg/kg in rats.
== External links == whatisbifidusregularis.org/ – A deconstruction of the terms Bifidus Actiregularis, Bifidus Regularis, Bifidus Digestivum, L. Casei Immunitas and their variants, as well as the marketing strategy, and information about the potential health benefits of live yoghurts. Food-Info.net – How to select a probiotic Type strain of Bifidobacterium animalis at BacDive – the Bacterial Diversity Metadatabase
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
不是。Semax 是完全人工合成的七肽，自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10)，但序列经过了替换和延长。