Everything below concerns intranasal route. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-03-21. Where a claim depends on a specific study, the study is described rather than over-claimed.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
| Property | Value | Notes |
|---|---|---|
| Purity assay | RP-HPLC, UV 214 nm | Typical research grade 95 percent or higher |
| Mass confirmation | ESI-MS or MALDI-TOF | Compared with theoretical value |
| Main degradation route | Methionine oxidation | Sulfoxide formation in solution |
| Powder storage | -20 °C, desiccated | Amber vial, minimal headspace |
| Working solution | Sterile water or saline | Prepare fresh; avoid repeated thawing |
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
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.
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.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
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.
=== Drug target === The anticonvulsant gabapentin [Neurontin; 1-(aminomethyl)cyclohexaneacetic acid] is a drug often used to treat patients with neuropathic pain. This neuropathic pain can be caused by a number of things, including diabetic neuropathy and postherpetic neuralgia. Gabapentin is an amino acid drug structurally similar to the two neurotransmitters glutamate (synthesized by BCATs) and GABA. The drug competitively inhibits both BCAT isoforms in the brain, slowing down glutamate production. Gabapentin also inhibits GABA aminotransferase (GABA-T) and glutamate dehydrogenase (GDH), two other enzymes in the glutamate and GABA metabolic pathway.
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula SO2. It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is released naturally by volcanic activity and is produced anthropogenically as a by-product of metals refining and the burning of fossil fuels for energy. Sulfur dioxide is somewhat toxic to humans, although only when inhaled in relatively large quantities for a period of several minutes or more. It was known to medieval alchemists as "volatile spirit of sulfur".
The carotid sheath is a condensation of the deep cervical fascia enveloping multiple vital neurovascular structures of the neck, including the common and internal carotid arteries, the internal jugular vein, the vagus nerve (CN X), and ansa cervicalis. The carotid sheath helps protects the structures contained therein.
== Lipid metabolism disorders == Lipid metabolism disorders (including inborn errors of lipid metabolism) are illnesses that disrupt normal processes in breaking down or synthesizing fats (or fat-like substances). Lipid metabolism disorders are associated with an increase in the concentrations of plasma lipids in the blood such as LDL cholesterol, VLDL, and triglycerides, which most commonly leads to cardiovascular diseases. Often these disorders are hereditary. Gaucher's disease (types I, II, and III), Niemann–Pick disease, Tay–Sachs disease, and Fabry's disease are all disorders of lipid metabolism. Rarer disorders of lipid metabolism include sitosterolemia, Wolman's disease, Refsum's disease, and cerebrotendinous xanthomatosis.
==== 2017–2018 service disruptions and track improvements ==== Since the early 2010s, Amtrak had planned to fix the deteriorating rails and infrastructure around Penn Station, but due to the prioritization of other projects, applied only minimal fixes. In early 2017, this culminated in numerous power outages, derailments, and delays due to track maintenance delays. There were frequent service disruptions to train schedules caused by the deterioration of its tracks and their supporting infrastructure, as well as in those of the East River and North River tunnels that respectively connect the station to Long Island and New Jersey. A string of early 2017 service disruptions started on March 23, 2017, when an Acela train derailed, causing delays for the day. On April 3, a NJ Transit train derailed at a known problem site, where repairs had been deferred. This caused four days of reduced service along the Northeast Corridor for both Amtrak and NJ Transit, because the incident damaged the switch that connects Tracks 1–8 to the North River tunnels. This closure caused a cascading failure, delaying Amtrak and Long Island Rail Road trains on the unaffected tracks. On April 14, a New Jersey Transit train became stuck in the North River tunnels, causing the station to grow crowded with waiting passengers. After an Amtrak police officer used a Taser on a man who was acting disruptively, rumors of gunshots sparked a stampede that injured 16 people. Following the stampede, U.S. Senator Chuck Schumer called on Amtrak to centralize law enforcement response.
Sources: en.wikipedia.org
=== Lewis acid === SO3 is a strong Lewis acid readily forming adducts with Lewis bases. With pyridine, it gives the sulfur trioxide pyridine complex. Related adducts form from dioxane and trimethylamine.
=== Legal status === In December 2016, a new drug application was filed with the US Food and Drug Administration (FDA), and in October 2017, an FDA advisory committee approved it unanimously. In December 2017, the injectable version with the brand name Ozempic was approved in the US for use by people with diabetes, and, in January 2018, in Canada. In February 2018, authorization was granted in the European Union, in March 2018 in Japan, and in August 2019 in Australia. A version of semaglutide to treat diabetes that can be taken orally (Rybelsus) was approved for medical use in the US in September 2019, and in the European Union in April 2020. In January 2023, the US FDA prescription label for Rybelsus was updated to reflect that it can be used as a first-line treatment for adults with type 2 diabetes. In June 2021, a higher-dose version for injectable use, sold under the brand name Wegovy, was approved by the FDA as an anti-obesity medication for long-term weight management in adults. In January 2022, Wegovy was approved for medical use in the European Union. In December 2025, an oral version of semaglutide, sold under the brand name Wegovy, was approved in the US for weight management. In March 2026, the CHMP recommended granting a conditional marketing authorization for Kayshild (semaglutide), a GLP-1 receptor agonist for the treatment of non-cirrhotic metabolic dysfunction-associated steatohepatitis (MASH) with liver fibrosis, a serious disease where fat deposits accumulate in the liver causing inflammation.
== Professional life == Following university, Eltenton began work in 1930 at the British Cotton Research Institute. In the summer of 1931 however, Eltenton visited a friend he had known at Cambridge, Yulii Khariton, at the Institute of Problems of Chemical Physics in Leningrad. He was offered a post in there, and moved to the USSR to work from 1933 until 1938, only leaving because, with the Soviet Great Purge, there was suspicion of foreigners. Like many others, his visa was not renewed, so he returned to England. The same year he published a paper in the prestigious journal Nature, showing the first identification of free radicals by mass spectrometer, and was invited to the research laboratories of Shell Development Corporation, California to build one of the first mass spectrometers in the US. Here he produced significant work on free radical mass spectrometry. In 1947 he returned to England, joining the research laboratory of Shell plc at Ellesmere Port, later transferring to the physics laboratory of Stanlow Refinery and producing a number of patents.
== Adverse effects == Nephrotoxicity: Like cisplatin, nephrotoxicity, harm to the kidneys, is the primary dose-limiting factor. However, the nephrotoxicity of nedaplatin has been shown to be less severe than cisplatin. In rats, nedaplatin primarily affected the renal papilla, with papillary necrosis in severe cases. Neurotoxicity: Nedaplatin is widely reported to be neurotoxic, especially to the nerves of the ear. Causing symptoms like numbness and tingling in mild cases, or sensory ataxia in more severe cases. Nausea and vomiting: The emetogenic effects of nedaplatin are commonly managed with prophylactic antiemetics, such as duplex dexamethasone and ondansetron or triplex dexamethasone, ondansetron and aprepitant. Ototoxicity: Nedaplatin is toxic to the nerve and hair cells in the cochlea. In rats, nedaplatin was severely toxic to the nerve cells at a concentration of 10 μM, with damage to hair cells becoming more severe exceeding 100 μM. Neutropenia, leukopenia, anemia and thrombocytopenia (see "Aqupla アクプラ" in External Links): Nedaplatin is toxic to the hemopoietic cells of the bone marrow, combined with reduced levels of erythropoietin, leads to elevated incidence of bone marrow suppression compared to cisplatin. Incidence of severe grades of leukopenia and neutropenia are reported to be higher than cisplatin in treatment combined with radiotherapy. These haematological adverse effects are common in general.
Animation – Astro Bot Artistic Achievement – Neva Audio Achievement – Astro Bot Best Game – Astro Bot British Game – Thank Goodness You're Here! Debut Game – Balatro Evolving Game – Vampire Survivors Family – Astro Bot Game Beyond Entertainment – Tales of Kenzera: Zau Game Design – Astro Bot Multiplayer – Helldivers 2 Music – Helldivers 2 Narrative – Metaphor: ReFantazio New Intellectual Property – Still Wakes the Deep Performer in a Leading Role – Alec Newman as Cameron "Caz" McLeary in Still Wakes the Deep Performer in a Supporting Role – Karen Dunbar as Finlay in Still Wakes the Deep Technical Achievement – Senua's Saga: Hellblade II
Sources: en.wikipedia.org
== See also == Allergy Diamine oxidase Food intolerance Granulocyte Histamine intolerance Histamine N-methyltransferase or HNMT Histamine List of distinct cell types in the adult human body Mast cell activation syndrome Mastocytosis
== Early life and education == Young grew up in southern Los Angeles, between Compton and Lynwood. He was raised by his great-grandparents. He spent most days at church, where he played drums for the choir. Channel left home to study music at Oral Roberts University, a private Christian university in Tulsa, Oklahoma.
The Tahitians (Tahitian: Māʼohi; French: Tahitiens) are the Indigenous Polynesian people of Tahiti and thirteen other Society Islands in French Polynesia. The numbers may also include the modern population in these islands of mixed Polynesian and French ancestry (French: demis). Indigenous Tahitians are one of the largest Polynesian ethnic groups, behind the Māori, Samoans and Hawaiians.
The flowering period starts in June and continues into mid-summer, although in northern countries it flowers rather later, sometimes as late as September, when it can fail to set seed. Its chromosome number is 2n = 20.
According to the International Programme on Chemical Safety (IPCS) and the U.S. Food and Drug Administration (FDA), amphetamine is contraindicated in people with a history of drug abuse, cardiovascular disease, severe agitation, or severe anxiety. It is also contraindicated in individuals with advanced arteriosclerosis (hardening of the arteries), glaucoma (increased eye pressure), hyperthyroidism (excessive production of thyroid hormone), or moderate to severe hypertension. These agencies indicate that people who have experienced allergic reactions to other stimulants or who are taking monoamine oxidase inhibitors (MAOIs) should not take amphetamine, although safe concurrent use of amphetamine and monoamine oxidase inhibitors has been documented. These agencies also state that anyone with anorexia nervosa, bipolar disorder, depression, hypertension, liver or kidney problems, mania, psychosis, Raynaud's phenomenon, seizures, thyroid problems, tics, or Tourette syndrome should monitor their symptoms while taking amphetamine. Evidence from human studies indicates that therapeutic amphetamine use does not cause developmental abnormalities in the fetus or newborns (i.e., it is not a human teratogen), but amphetamine abuse does pose risks to the fetus. Amphetamine has also been shown to pass into breast milk, so the IPCS and the FDA advise mothers to avoid breastfeeding when using it. Due to the potential for reversible growth impairments, the FDA advises monitoring the height and weight of children and adolescents prescribed an amphetamine pharmaceutical.
Sources: en.wikipedia.org
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.
The main chemical risks are methionine oxidation and backbone hydrolysis in solution. Moisture and repeated temperature cycling accelerate both processes. Dry powder held cold and desiccated is considerably more stable than any reconstituted preparation.
It holds a medicine registration in Russia, where it has been used clinically for decades. In most other countries it is treated as a research chemical. That split explains the uneven distribution of clinical literature.
不存在。它是依据 ACTH 的一段序列人工设计的分子，天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号，而非天然物质名。