The short version of ACTH fragment fits in a sentence. The long version — which is the one that helps — is below.
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The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
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。
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.
=== Industrial synthesis === Vitamin D3 (cholecalciferol) is produced industrially by exposing 7-dehydrocholesterol to UVB and UVC light, followed by purification. The 7-dehydrocholesterol is sourced as an extraction from lanolin, a waxy skin secretion in sheep's wool. Vitamin D2 (ergocalciferol) is produced in a similar way using ergosterol from yeast as a starting material.
In March 2016, the International Narcotics Control Board stated that the UN's international drug treaties do not mandate a "war on drugs" and that the choice is not between "'militarized' drug law enforcement on one hand and the legalization of non-medical use of drugs on the other", health and welfare should be the focus of drug policy. That April, the UN General Assembly Special Session (UNGASS) on the "World Drug Problem" was held. The Wall Street Journal assessed the attendees' positions as "somewhat" in two camps: "Some European and South American countries as well as the U.S. favored softer approaches. Eastern countries such as China and Russia and most Muslim nations like Iran, Indonesia and Pakistan remained staunchly opposed." The outcome document recommended treatment, prevention and other public health measures, and committed to "intensifying our efforts to prevent and counter" drug production and trafficking, through, "inter alia, more effective drug-related crime prevention and law enforcement measures." Under President Donald Trump (2017–2021), Attorney General Jeff Sessions reversed the previous Justice Department's cannabis policies, rescinding the Cole Memo that deferred federal enforcement in states where cannabis had been legalized He instructed federal prosecutors to "charge and pursue the most serious, readily provable offense" in drug cases, regardless of whether mandatory minimum sentences applied, which could trigger mandatory minimums for lower-level charges.
A trap requires confining forces in all three spatial directions. Electric and magnetic fields exert forces on ions, called the Lorentz force. Due to Earnshaw's theorem it is not possible to confine an ion using only static electric fields. However, a static magnetic and electric field (a Penning trap), or the combination of an oscillating electric field with a static electric field (a Paul trap), can trap ions. The confining fields and the resulting motion of ions in a trap are generally decomposed into one axial and two radial components with respect to the trap geometry. In both Paul and Penning traps, a static electric field provides the axial confinement. Paul traps confine the ion radially with an oscillating electric field whereas Penning traps use a static magnetic field.
=== Pharmacokinetics === Flurpiridaz (18F) has peak blood radioactivity at 2.3 minutes after administration, followed by a rise and plateau. Distribution of this radiopharmaceutical is complex, as it transfuses into the liver (13%), kidneys (9%), brain (8%) and epicardium (3%, radioactivity retains for 1 hour after administration). Full clearance is achieved within 48 hours. Only metabolites of flurpiridaz are excreted, mainly in urine and feces. Flurpiridaz metabolises into many different polar metabolites. There are no differences in pharmacokinetics caused by age, sex, body mass index (BMI), diabetic status, Clid Pugh A hepatic impairment and renal impairment at eGFR≥19-89 mL/min.
Centers for Disease Control: Obesity Data and Statistics American Obesity Treatment Association: Obesity Education and Statistics Archived February 28, 2021, at the Wayback Machine Contributors to Obesity | Tableau Public Archived January 3, 2015, at the Wayback Machine (infographic for the United States)
Sources: en.wikipedia.org
both patentable and otherwise, should be shared 'without fee or stipulation'", or, given the "[difference] between patenting for personal gain and patenting in the public interest" whether "a new process or discovery [should be patented] in the public interest" — the medical profession had a further concern. The term, "patented medicine" strongly suggested the unscientific, testimonial-promoted, "cure all" preparation of the charlatan, quack, or snake oil salesman, universally known as a patent medicine. In 1911, the "free use" of more than 90% of the 250 patents that had been issued by the Patent Office to government employees had been given over, by those patentees, to "the government and the people of the United States". Given that, if the invention was "of any value", and the employee had not patented it, "there is the chance at any time that somebody else may take out the patent and collect royalties from the public", patenting was "for the protection of the public rather than for the protection of the patentee" and, in doing so, also "prevent[ed] some more mercenary individual from collecting royalties". In 1907, Frederick Cottrell, a colleague of Robertson's at the University of California, patented his electrostatic precipitator, designed to produce cleaner industrial chimney emissions (FC.1), and offered the rights to the University. From their view that the university's Charter precluded any commercial activity, the Regents of the University of California declined Cottrell's offer.
=== Personal care products === Personal care products often contain a complex mixture of chemicals such as preservatives (e.g., parabens), UV filters (e.g., oxybenzone), plasticizers (e.g., phthalates), antimicrobials (e.g., triclosan), fragrances, and colorants. Many of these compounds are synthesized chemicals that are not typically found in nature. Chemicals from personal care products can enter the environment through various pathways. After use, they are often washed down the drain and can end up in the wastewater stream. These substances are not all completely removed by conventional wastewater treatment processes, leading to their release into natural water bodies. Some of these chemicals are persistent in the environment and can bioaccumulate in the tissues of organisms, potentially causing ecological disruptions. They can also have endocrine-disrupting properties that interfere with the hormonal systems of wildlife and humans.
Drug decriminalisation, such as allowing the possession of small amounts of cannabis and possibly its cultivation for personal use, would alleviate these harms. Where decriminalisation has been implemented, such as in several states in Australia and United States, as well as in Portugal and the Netherlands no, or only very small adverse effects have been shown on population cannabis usage rate. The lack of evidence of increased use indicates that such a policy shift does not have adverse effects on cannabis-related harm while, at the same time, decreasing enforcement costs. In the last few years certain strains of the cannabis plant with higher concentrations of THC and drug tourism have challenged the former policy in the Netherlands and led to a more restrictive approach; for example, a ban on selling cannabis to tourists in coffeeshops suggested to start late 2011. Sale and possession of cannabis is still illegal in Portugal and possession of cannabis is a federal crime in the United States.
A method of sunless tanning is consumption of certain carotenoids—antioxidants found in some fruits and vegetables such as carrots and tomatoes—which can result in changes to skin color when ingested chronically and/or in high amounts. Carotenoids are long-lasting. In addition, carotenoids have been linked to a more attractive skin tone (defined as a more golden skin color) than suntan. Carotenes also fulfil the function of melanin in absorbing UV radiation and protecting the skin. For example, they are concentrated in the macula of the eye to protect the retina from damage. They are used in plants both to protect chlorophyll from light damage and harvest light directly. Carotenaemia (xanthaemia) is the presence in blood of the yellow pigment carotene from excessive intake of carrots or other vegetables containing the pigment resulting in increased serum carotenoids. It can lead to subsequent yellow-orange discoloration (xanthoderma or carotenoderma) and their subsequent deposition in the outermost layer of skin. Carotenemia, or carotenoderma, is in itself harmless, and does not require treatment. In primary carotenoderma, when the use of high quantities of carotene is discontinued the skin color will return to normal. It may take up to several months, however, for this to happen.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
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.