neurotrophic factor raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
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.
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
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.
Vortioxetine increases serotonin concentrations in the brain by inhibiting its reuptake in the synapse, and also modulates (activates or blocks) certain serotonin receptors. This puts it in the class of serotonin modulators and stimulators, which also includes vilazodone. More specifically, vortioxetine is a serotonin reuptake inhibitor, agonist of the serotonin 5-HT1A receptor, partial agonist of the 5-HT1B receptor, and antagonist of the serotonin 5-HT1D, 5-HT3, and 5-HT7 receptors, as well as an apparent ligand of the β1-adrenergic receptor. In terms of functional activity however, vortioxetine appears to be much more potent on serotonin reuptake inhibition and 5-HT3 receptor antagonism than for its interactions with the other serotonin receptors. Whereas vortioxetine has IC50 or EC50 values of 5.4 nM for the SERT and 12 nM for the 5-HT3 receptor, its values are 120 to 450 nM for the 5-HT1A, 5-HT1B, 5-HT1D, and 5-HT7 receptors. This translates to about 22- to 83-fold selectivity for SERT inhibition and 10- to 38-fold selectivity for 5-HT3 antagonism over activities at the other serotonin receptors. 5-HT3 antagonism appears to have a better effect on REM sleep compared to paroxetine. The serotonin transporter (SERT) and 5-HT3 receptor are claimed to be primarily occupied at lower clinical doses of vortioxetine and that the 5-HT1B, 5-HT1A, and 5-HT7 receptors may additionally be occupied at higher doses.
==== Remittance tax ==== Effective January 1, 2026, the law establishes a 1% excise tax on certain electronic transfers of funds from the United States to a foreign country. The tax is on the electronic transfer of funds from an individual located in any U.S. state, U.S. territory, or the District of Columbia to a recipient in a foreign country for personal, family, or household purposes. The excise tax is assessed on electronic transfers sent using cash, money orders, cashier's checks, prepaid card reloads, wire transfers, online bill payments, and similar methods. The excise tax is assessed on the amount transferred and not on any fees that the sending institution charges the sender to complete the transfer. The excise tax is supposed to be paid by the sender of the remittance; the transfer provider must pay the excise tax if the sender does not. A transfer to a U.S. military base located in a foreign country are considered to be received in the United States and is not subject to the remittance tax. Additionally, transfers of $15 or less are not subject to the remittance tax. Certain transfers are exempt, such as those from financial accounts held at institutions subject to the Bank Secrecy Act, such as U.S. banks, U.S. credit unions, U.S. investment companies, and certain U.S. branches of foreign banks; transfers paid with a U.S.-issued debit or credit card; and transfers of cryptocurrency.
Videos that users do not want to post yet can be stored in their "drafts". The user is allowed to see their "drafts" and post when they find it fitting. Users can also use portions of other TikTok videos by creating a "stitch". TikTok announced a "family safety mode" in February 2020 for parents to be able to control their children's presence on the app. There is a screen time management option, restricted mode, and the option to put a limit on direct messages. The app expanded its parental controls feature called "Family Pairing" in September 2020 to provide parents and guardians with educational resources to understand what children on TikTok are exposed to. Content for the feature was created in partnership with online safety nonprofit, Internet Matters. In October 2021, TikTok launched a test feature that allows users to directly tip certain creators. Accounts of users that are of age, have at least 100,000 followers and agree to the terms can activate a "Tip" button on their profile, which allows followers to tip any amount, starting from $1. In December 2021, TikTok started beta-testing Live Studio, a streaming software that would let users broadcast applications open on their computers, including games. The software also launched with support for mobile and PC streaming. However, a few days later, users on Twitter discovered that the software uses code from the open-source OBS Studio. OBS made a statement saying that, under the GNU GPL version 2, TikTok has to make the code of Live Studio publicly available if it wants to use any code from OBS.
== Metabolism == In mammals, 1,6-dichloro-1,6-dideoxyfructose is metabolized in the liver and erythrocytes by a reaction with glutathione that replaces one of the chlorine atoms, forming 6-chlorofructos-1-yl glutathione (or chlorofructosyl glutathione).
Sources: en.wikipedia.org
Through the development of a peptide microarray platform, his group uncovered mechanisms of DNA methylation maintenance and defined modes of chromatin engagement by distinct families of histone-binding effector domains. Recent work has also turned to how recently defined effector domains, including the YEATS domain, contribute to chromatin function and metabolic transcription
== Other animals == Degenerative disc disease can occur in other mammals besides humans. It is a common problem in several dog breeds, such as the Dachshund, and attempts to remove this disease from dog populations have led to several hybrid breeds, such as the Chiweenie.
=== Potency of laudanum === Opium tincture is one of the most potent oral formulations of morphine available by prescription. Accidental or deliberate overdose is easily possible with opium tincture given the highly concentrated nature of the solution. Overdose and death may occur with a single oral dose of between 100 and 150 mg of morphine in a healthy adult who has no tolerance to opiates. This represents the equivalent of between two and three teaspoons (10–15 mL) of opium tincture. Overdose of laudanum was an occurrence in the mid-19th century. Prudent medical judgment necessitates toward dispensing very small quantities of opium tincture in small dropper bottles or in pre-filled syringes to reduce the risk of intentional or accidental overdose.
Rilonacept, sold under the brand name Arcalyst, is a medication used to treat cryopyrin-associated periodic syndromes, including familial cold autoinflammatory syndrome, and Muckle–Wells syndrome; deficiency of interleukin-1 receptor antagonist; and recurrent pericarditis. Rilonacept is an interleukin 1 inhibitor. Rilonacept is a dimeric fusion protein consisting of the ligand-binding domains of the extracellular portions of the human interleukin-1 receptor component (IL-1R1) and IL-1 receptor accessory protein (IL-1RAcP) linked in-line to the fragment-crystallizable portion (Fc region) of human IgG1 that binds and neutralizes IL-1. Rilonacept was given an orphan drug designation by the U.S. Food and Drug Administration (FDA) and is used for the treatment of cryopyrin-associated periodic syndromes (CAPS), including familial cold autoinflammatory syndrome, Muckle–Wells syndrome. Rilonacept is the first drug approved by the FDA to treat recurrent pericarditis. Rilonacept was approved for medical use in the United States in February 2008. On May 8, 2012, an FDA Advisory Panel voted 11–0 against the approval of rilonacept for the treatment of gout, stating that the benefits did not outweigh the risks associated with the drug.
== Biological importance == Aside from the necessity of wobble, that our cells have a limited amount of tRNAs and wobble allows for more flexibility, wobble base pairs have been shown to facilitate many biological functions, most clearly demonstrated in the bacterium Escherichia coli, a model organism. In fact, in a study of E. coli's tRNA for alanine there is a wobble base pair that determines whether the tRNA will be aminoacylated. When a tRNA reaches an aminoacyl tRNA synthetase, the job of the synthetase is to join the t-shaped RNA with its amino acid. These aminoacylated tRNAs go on to the translation of an mRNA transcript, and are the fundamental elements that connect to the codon of the amino acid. The necessity of the wobble base pair is illustrated through experimentation where the Guanine-Uracil pairing is changed to its natural Guanine-Cytosine pairing. Oligoribonucleotides were synthesized on a Gene Assembler Plus, and then spread across a DNA sequence known to code a tRNA for alanine, 2D-NMRs are then run on the products of these new tRNAs and compared to the wobble tRNAs. The results indicate that with that wobble base pair changed, structure is also changed and an alpha helix can no longer be formed. The alpha helix was the recognizable structure for the aminoacyl tRNA synthetase and thus the synthetase does not connect the amino acid alanine with the tRNA for alanine. This wobble base pairing is essential for the use of the amino acid alanine in E. coli and its significance here would imply significance in many related species.
Sources: en.wikipedia.org
Administratively, Le Havre is a commune in the Normandy region in the west of the department of Seine-Maritime. The urban area of Le Havre corresponds roughly to the territory of the Agglomeration community of Le Havre (CODAH) which includes 17 communes and 250,000 people. It occupies the south-western tip of the natural region of Pays de Caux where it is the largest city. Le Havre is sandwiched between the coast of the Channel from south-west to north-west and the estuary of the Seine to the south.
=== Interleukin-4 and -10 === IL-4 is a pleiotropic cytokine that plays a key role in the development of T helper type 2(Th2) cells. IL-4 is important for the differentiation of naïve CD4-T cells into mature Th2 type cells; as well as for Immunoglobulin (Ig) class switching to IgE and IgG4 during the development of immune responses. Ig is a class of antibody found only in mammals that plays an important role in allergy response and defense against many kinds of pathogens by protecting the body against them by complement activation, opsonization for phagocytosis, and neutralization of their toxins. IL-4 and IL-10 have both been shown to reduce the production of metalloproteinases (endopeptidases which break down collagen and other extracellular proteins) by human AMs. IL-4 has dual effects upon macrophage biological function, which may be either stimulatory or inhibitory. It enhances MHC class II antigen (extracellular protein complex that interacts exclusively with CD4-T cells as part of the exogenous pathway) and Mac-1(surface receptor as part of innate complement system) expression, thus promoting phagocytosis. IL-4 has also been shown to inhibit the production of PGE2 by reducing the expression of the enzyme, prostaglandin H synthase -2 (PGHS-2), which is critical in the production of PGE2. However, IL-4 inhibits production of TNF-alpha, IL-1 and -6, which are all important cytokines in the proinflammatory response). IL-10 inhibits the secretion of pro-inflammatory cytokines TNF-alpha and INF-gamma, thus suppressing the proliferation of T-cells, NK cells, and AM.
As of 2014, low-end refurbished 60 MHz and 90 MHz systems were sold as FT–NMR instruments, and in 2010 the "average workhorse" NMR instrument was configured for 300 MHz. CW spectroscopy is inefficient in comparison with Fourier analysis techniques (see below) since it probes the NMR response at individual frequencies or field strengths in succession. Since the NMR signal is intrinsically weak, the observed spectrum suffers from a poor signal-to-noise ratio. This can be mitigated by signal averaging, i.e. adding the spectra from repeated measurements. While the NMR signal is the same in each scan and so adds linearly, the random noise adds more slowly – proportional to the square root of the number of spectra added (see random walk). Hence the overall signal-to-noise ratio increases as the square-root of the number of spectra measured. However, monitoring an NMR signal at a single frequency as a function of time may be better suited for kinetic studies than pulsed Fourier-transform NMR spectrosocopy.
=== Fungal === Fungal steroids include the ergosterols, which are involved in maintaining the integrity of the fungal cellular membrane. Various antifungal drugs, such as amphotericin B and azole antifungals, use this information to kill pathogenic fungi. Fungi can alter their ergosterol content (e.g. through loss of function mutations in the enzymes ERG3 or ERG6, inducing depletion of ergosterol, or mutations that decrease the ergosterol content) to develop resistance to drugs that target ergosterol. Ergosterol is analogous to the cholesterol found in the cellular membranes of animals (including humans), or the phytosterols found in the cellular membranes of plants. All mushrooms contain large quantities of ergosterol, in the range of tens to hundreds of milligrams per 100 grams of dry weight. Oxygen is necessary for the synthesis of ergosterol in fungi. Ergosterol is responsible for the vitamin D content found in mushrooms; ergosterol is chemically converted into provitamin D2 by exposure to ultraviolet light. Provitamin D2 spontaneously forms vitamin D2. However, not all fungi use ergosterol in their cellular membranes; for example, the pathogenic fungal species Pneumocystis jirovecii does not, which has important clinical implications (given the mechanism of action of many antifungal drugs). Using the fungus Saccharomyces cerevisiae as an example, other major steroids include ergosta‐5,7,22,24(28)‐tetraen‐3β‐ol, zymosterol, and lanosterol. S. cerevisiae uses 5,6‐dihydroergosterol in place of ergosterol in its cell membrane.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
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.