This is a working overview of intranasal route, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-03-10. Anything still debated is marked as such rather than presented as settled.
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.
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。
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
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.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
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.
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.
=== Biomedical applications === Ethyl carbamate was originally used as an antineoplastic agent, hypnotic, sclerosing agent, adjunct to sulfonamide therapy, and topical bactericide. It was discovered to be carcinogenic in 1943 and largely ineffective at treating multiple myeloma, according to a study published in 1966. It was removed from the market in the US, UK and Canada in 1963 and was classified as a 2B carcinogen by the IARC in 1974. However, its use in Japan as a co-solvent in water for dissolving water-insoluble analgesics used for post-operation pain, at doses estimated to be at levels that are carcinogenic in mice, continued until 1975. Miller has suggested that this may have been the "largest number (millions) of humans exposed to the largest doses of a pure carcinogen that is on record" and called for studies to determine the effects on Japanese cancer rates to be performed. Ethyl carbamate continues to be used as an anaesthetic in animal experiments, with more than 100 animal studies using ethyl carbamate published each year. One advantage of using ethyl carbamate is that it has a very long duration of action, with some adult rats remaining anaesthetised 24 hours after administration of the drug. It also does not depress neuronal activity in the cortex to the same extent as isoflurane.
==== Biden administration ==== On 13 February 2021, the White House said it had "deep concerns" about both the way the WHO's findings were communicated and the process used to reach them. Mirroring concerns raised by the Trump administration, National Security Advisor Jake Sullivan stated that it was essential that the WHO-convened report be independent and "free from alteration by the Chinese government". On 14 April 2021, the Director of National Intelligence Avril Haines, along with other Biden administration officials, said that they had not ruled out the possibility of a laboratory accident as the origin of the COVID-19 virus. On 26 May 2021, President Joe Biden directed the U.S. intelligence community to produce a report within 90 days on whether the COVID-19 virus originated from human contact with an infected animal or from an accidental lab leak, stating his national security staff said there is insufficient evidence to determine either hypothesis to be more likely. On 26 August 2021, the Office of the Director of National Intelligence released an unclassified summary of their findings, with the main point being that the report remained inconclusive as to the origin of the virus, with intelligence agencies divided on the question. The report also concluded that the virus was most likely not genetically engineered, and that China had no foreknowledge of the virus prior to the outbreak.
=== Dating === Dating Lindow Man is difficult as samples from the body and surrounding peat have produced dates spanning a 900-year period. Although the peat encasing Lindow Man has been radiocarbon dated to about 300 BC, Lindow Man himself has a different date. Early tests at different laboratories returned conflicting dates for the body; later tests suggested a date between 2 BC and 119 AD. There has been a tendency to ascribe the body to the Iron Age period rather than Roman because of the interpretation that Lindow Man's death may have been a ritual sacrifice or execution. Explanations for why the peat in which he was found is much older have been sought. Archaeologist P. C. Buckland suggests that as the stratigraphy of the peat appears undisturbed, Lindow Man may have been deposited into a pool that was already some 300 years old. Geographer K. E. Barber has argued against this hypothesis, saying that pools at Lindow Moss would have been too shallow, and suggests that the peat may have been peeled back to allow the burial and then replaced, leaving the stratigraphy apparently undisturbed.
== Career == Sinclair met Massachusetts Institute of Technology professor Leonard P. Guarente in 1993. Guarente had studied yeast as a model of aging, and after meeting him, Sinclair interviewed for a post-doc position in Guarente's lab. He worked as a postdoctoral researcher for Guarente for four years and in 1999 he was hired at Harvard Medical School. In 2004, Sinclair met with the philanthropist Paul F. Glenn who donated $5 million to Harvard to establish the Paul F. Glenn Laboratories for the Biological Mechanisms of Aging at Harvard, of which Sinclair became the founding director. In 2004, Sinclair founded Sirtris Pharmaceuticals along with Andrew Perlman, Christoph Westphal, Richard Aldrich, Richard Pops, and Paul Schimmel. Sirtris was focused on developing Sinclair's research into activators of sirtuins, work that began in the Guarente lab. The company was specifically focused on resveratrol formulations and derivatives as activators of the SIRT1 enzyme; Sinclair became known for making statements about resveratrol like: "(It's) as close to a miraculous molecule as you can find. ... One hundred years from now, people may be taking these molecules on a daily basis to prevent heart disease, stroke, and cancer." Most of the anti-aging field was more cautious, especially with regard to what else resveratrol might do in the body and its lack of bioavailability. The company went public in 2007 and was subsequently purchased by and made a subsidiary of GlaxoSmithKline in 2008 for $720 million.
Eric plans to have Jesse to sell his shares to Felim at the shoot, but Harper instead covertly helps Jesse buy a controlling stake in Rican from FutureDawn Partners, a socially conscious investment fund, seeing as Rican is underperforming and hiding it from Felim to ensure his investment. Felim, realizing Eric has yet again failed to deliver on his promises, cuts ties with him for good.
Sources: en.wikipedia.org
Cnidarians form a phylum of animals that are more complex than sponges, about as complex as ctenophores (comb jellies), and less complex than bilaterians, which include almost all other animals. Both cnidarians and ctenophores are more complex than sponges as they have: cells bound by inter-cell connections and carpet-like basement membranes; muscles; nervous systems; and some have sensory organs. Cnidarians are distinguished from all other animals by having cnidocytes that fire harpoon-like structures that are mainly used to capture prey. In some species, cnidocytes can also be used as anchors. Cnidarians are also distinguished by the fact that they have only one opening in their body for ingestion and excretion i.e. they do not have a separate mouth and anus. Like sponges and ctenophores, cnidarians have two main layers of cells that sandwich a middle layer of jelly-like material, which is called the mesoglea in cnidarians; more complex animals have three main cell layers and no intermediate jelly-like layer. Hence, cnidarians and ctenophores have traditionally been labelled diploblastic, along with sponges. However, both cnidarians and ctenophores have a type of muscle that, in more complex animals, arises from the middle cell layer. As a result, some recent text books classify ctenophores as triploblastic, and it has been suggested that cnidarians evolved from triploblastic ancestors.
As tensions heightened on 8 October 2023 near the Lebanese border, former prime minister Fouad Siniora stressed that Lebanon should not be involved "in any hostilities with the Israeli enemy". Between 7–9 October 2023, many politicians of long-established Christian parties in Lebanon took a stance against Hezbollah's involvement as well. Pierre Bou Assi, a member of the Lebanese Forces's Strong Republic bloc highlighted the kidnapping of two IDF soldiers which led to the 2006 Lebanon war saying, "Hassan Nasrallah promised, in early July, that the summer would be quiet and thriving—but a few days later, Hezbollah kidnapped two Israeli soldiers and the July war broke out". The Kataeb Party took a similar stance and condemned the use of Lebanese territory by non-state actors for launching attacks on Israel. On 4 December 2023, Hamas announced the organization's official establishment in Lebanon. The Lebanon-based unit was named the "al-Aqsa Flood Vanguards unit". The establishment of the Vanguards during the 2023 Hamas-led attack on Israel faced severe criticism from various political figures and factions within Lebanon. Many argued that such an organization, with potential military implications, could infringe upon Lebanon's sovereignty and violate international resolutions, particularly the Taif Agreement. Critics, including members of the Christian Lebanese Forces Party and other political figures, voiced concerns about a potential recurrence of historical issues related to armed Palestinian factions operating from Lebanese territory.
Irresponsibility on the part of the radioactive material's owners, usually a hospital, university, or military, and the absence of regulation concerning radioactive waste, or a lack of enforcement of such regulations, have been significant factors in radiation exposures. For an example of an accident involving radioactive scrap originating from a hospital, see the Goiânia accident. Transportation accidents involving spent nuclear fuel from power plants are unlikely to have serious consequences due to the strength of the spent nuclear fuel shipping casks. On 15 December 2011, top government spokesman Osamu Fujimura of the Japanese government admitted that nuclear substances were found in the waste of Japanese nuclear facilities. Although Japan did commit itself in 1977 to inspections in the safeguard agreement with the IAEA, the reports were kept secret for the inspectors of the International Atomic Energy Agency. Japan did start discussions with the IAEA about the large quantities of enriched uranium and plutonium that were discovered in nuclear waste cleared away by Japanese nuclear operators. At the press conference Fujimura said: "Based on investigations so far, most nuclear substances have been properly managed as waste, and from that perspective, there is no problem in safety management," but according to him, the matter was at that moment still being investigated.
In some cases, withdrawal symptoms may be prevented by taking medication as directed, and when discontinuing, doing so gradually, although symptoms may appear while tapering. When discontinuing an antidepressant with a short half-life, switching to a drug with a longer half-life (e.g., fluoxetine or citalopram) and then tapering, and eventually discontinuing, from that drug can decrease the severity of symptoms in some cases. Gradual tapering over weeks to months is commonly recommended to reduce withdrawal symptoms, although direct comparative evidence on optimal taper duration is limited. A NICE committee noted that variability in withdrawal symptoms and tapering response among patients prevented the recommendation of a specific tapering timeline, and that an individualized approach to tapering is warranted. Treatment is dependent on the severity of the discontinuation reaction and whether or not further antidepressant treatment is warranted. In cases where further antidepressant treatment is prescribed, then the only option suggested may be restarting the antidepressant. If antidepressants are no longer required, treatment depends on symptom severity. If symptoms of discontinuation are severe, or do not respond to symptom management, the antidepressant can be reinstated and then withdrawn more cautiously, or by switching to a drug with a longer half-life (e.g., fluoxetine), and then tapering and discontinuing that drug. In severe cases, hospitalization may be required.
Sources: en.wikipedia.org
Several small-scale studies involving 15 or fewer test subjects conducted in the 1950s and 1960s reported that adrenochrome triggered psychotic reactions such as thought disorder and derealization. In 1954, researchers Abram Hoffer and Humphry Osmond claimed that adrenochrome is a neurotoxic, psychotomimetic substance and may play a role in schizophrenia and other mental illnesses. In what Hoffer called the "adrenochrome hypothesis", he and Osmond in 1967 speculated that megadoses of vitamin C and niacin could cure schizophrenia by reducing brain adrenochrome. The treatment of schizophrenia with such potent anti-oxidants is controversial. In 1973, the American Psychiatric Association reported methodological flaws in Hoffer's work on niacin as a schizophrenia treatment and referred to follow-up studies that did not confirm any benefits of the treatment. Multiple additional studies in the United States, Canada, and Australia similarly failed to find benefits of megavitamin therapy to treat schizophrenia. The adrenochrome theory of schizophrenia waned, despite some evidence that it may be psychotomimetic, as adrenochrome was not detectable in people with schizophrenia. In the early 2000s, interest was renewed by the discovery that adrenochrome may be produced normally as an intermediate in the formation of neuromelanin. This finding may be significant because adrenochrome is detoxified at least partially by glutathione-S-transferase. Some studies have found genetic defects in the gene for this enzyme. Adrenochrome is also believed to have cardiotoxic properties.
=== Medical use === Hemocyte extracts from horseshoe crabs are commonly used in drug and medical device testing for these coagulative properties. Clotting indicates that endotoxins are present in the product.
Following concerns over the fate of 7-Eleven Speak Out Wireless customers, Quickie offered the option for SpeakOut customers to port into the Good2Go mobile provider. SpeakOut subsequently offered online sales as an option, and continues to offer Ottawa-based phone numbers to new and existing customers.
Sources: en.wikipedia.org
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.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
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。