This is a working overview of Tuftsin, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-12-01 and is reviewed periodically as new material appears.
The primary structure of Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, corresponding to the molecular formula C33H57N11O9 and a monoisotopic mass of roughly 751.9 daltons. The N-terminal threonine and the arginine residue in the fourth position are shared with tuftsin, which carries the sequence Thr-Lys-Pro-Arg. The three additional residues at the C-terminus, Pro-Gly-Pro, extend the chain and are associated with greater resistance to enzymatic degradation. This extension also separates Selank from the shorter parent peptide.
Naming conventions place Selank in the same research family as Semax, another Russian-developed peptide investigated for cognitive effects. The two compounds share a lineage but differ in sequence and in the biological systems proposed as their targets. Semax descends from ACTH fragments, whereas Selank descends from tuftsin. Publications sometimes identify Selank by its full peptide sequence or by laboratory codes rather than one uniform trade name. Because replication outside Russia is limited, reports on its properties are best read alongside the study design and the purity of the material tested.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Stabilized analog of tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Monoisotopic mass about 751.9 Da |
| Appearance | White to off-white powder | Typically supplied as lyophilized solid |
| Solubility | Freely soluble in water | Also soluble in common polar solvents |
Proposed mechanisms centre on modulation of the GABAergic system, with reports of altered expression of genes related to GABA-A receptor subunits and changed monoamine turnover. Some studies describe inhibition of enkephalinase, the enzyme that degrades endogenous enkephalins, which may prolong opioid peptide signalling. Effects on brain-derived neurotrophic factor and on cytokine expression have also been reported. These findings come largely from animal models and small human studies, and the precise primary target remains unresolved.
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
Selank is a synthetic heptapeptide developed in Russia. Its sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, a seven-residue chain built around the natural tetrapeptide tuftsin. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences first described the compound in the mid-1990s. The design combined the tuftsin core with an added Pro-Gly-Pro tail, a modification intended to extend the molecule's stability in biological fluids. Published work on the peptide has appeared mainly in Russian-language journals.
Reported activity for Selank centers on anxiolytic and nootropic effects. Russian clinical reports describe use in anxiety and in cognitive or attention-related complaints. Most of this evidence comes from studies conducted by the same research groups that developed the peptide. Independent replication in other countries remains limited, and no major Western regulatory agency has approved the compound for any indication. The gap between local reports and external verification is a recurring point in discussions of the peptide.
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Purity assessment relies mainly on reverse-phase high-performance liquid chromatography with ultraviolet detection. Because the peptide lacks a strong chromophore, detection often uses backbone absorbance near 214 nm. Identity is confirmed by mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, comparing the measured mass against the expected value. Amino acid analysis can verify composition after acid hydrolysis. Diastereomer content and residual counterions are reported less often, although both can influence biological assays.
Lyophilized material is generally stable for extended periods when kept dry at or below minus twenty degrees Celsius. Working solutions are less stable, and common practice is to aliquot and freeze them so that repeated freeze-thaw cycles are avoided. Aqueous solutions are sensitive to pH extremes and to microbial growth, so short-term storage at refrigerator temperature is typical. Oxidation and hydrolysis are the principal degradation routes. Reconstitution with sterile water or a mild buffer is standard, and solutions should be protected from light.
Regulatory treatment varies by jurisdiction. In Russia the compound is a registered prescription product, while in the European Union and the United States it is generally handled as a research chemical without a marketing authorization. Suppliers therefore operate outside pharmaceutical oversight, and buyers rely on supplier documentation for purity and identity claims. Chain of custody and third-party testing are the main verification tools. Analysts note that the absence of a pharmacopoeial monograph for research-grade material limits standardization across vendors.
== Diversity == There are a large number of different odor receptors, with as many as 2,000 in the mammalian genome which, depending on the species represents up to 5% of the coding-genes in the genome. However, not all of these potential odor receptor genes are expressed and functional. According to an analysis of data derived from the Human Genome Project, humans have approximately 400 functional genes coding for olfactory receptors, and the remaining 600 candidates are pseudogenes. The reason for the large number of different odor receptors is to provide a system for discriminating between as many different odors as possible. Even so, each odor receptor does not detect a single odor. Rather each individual odor receptor is broadly tuned to be activated by a number of similar odorant structures. Analogous to the immune system, the diversity that exists within the olfactory receptor family allows molecules that have never been encountered before to be characterized. However, unlike the immune system, which generates diversity through in-situ recombination, every single olfactory receptor is translated from a specific gene; hence the large portion of the genome devoted to encoding OR genes. Furthermore, most odors activate more than one type of odor receptor. Since the number of combinations and permutations of olfactory receptors is very large, the olfactory receptor system is capable of detecting and distinguishing between a very large number of odorant molecules.
"The social and psychological functions of popular music [are that it] acts like a social cement" "to keep people obedient and subservient to the status quo of existing power structures." Serious music, according to Adorno, achieves excellence when its whole is greater than the sum of its parts. The example he gives is that of Beethoven's symphonies: "[his] greatness shows itself in the complete subordination of the accidentally private melodic elements to the form as a whole." Standardization not only refers to the products of the culture industry but also to the consumers as well. Many times every day consumers are bombarded by media advertising. Consumers are pushed and shoved into consuming products and services presented to them by a media system that takes advantage of musical hooks mass-produced via electronic media. The masses have become conditioned by the culture industry, which makes the impact of standardization far more widespread. Not recognizing the impact of social media and commercial advertising, the individual is caught in a situation where conformity is the norm: "During consumption, the masses become characterized by the commodities which they use and exchange among themselves." Tony Waters and David Philhour have tested Adorno's ideas and used musical intros from pop songs and asked students in the United States, Germany, and Thailand what they recognize. They found that indeed, as Adorno hypothesized, song intro recognition has spread around the world for some specific commercial pop songs.
== Epidemiology == The current estimated global incidence annually is 20,000 to 50,000 people, though a large number of cases are believed to go unreported. Due to the limited habitats of ciguatoxin-producing microorganisms, ciguatera is common only in subtropical and tropical waters, particularly the Pacific and Caribbean, and usually is associated with fish caught in tropical reef waters. Exportation of reef fish, as well as tourism, often account for cases that develop in other regions. Ciguatoxin is found in over 400 species of reef fish. Avoiding consumption of all reef fish is the only sure way to avoid exposure. Imported fish served in restaurants may contain the toxin and produce illness which often goes unexplained by physicians unfamiliar with the symptoms of a tropical toxin. Ciguatoxin can also occur in farm-raised salmon. Furthermore, species substitution, labeling a reef fish as a non-reef fish at restaurants and retail, can complicate efforts by consumers to avoid ciguatera.
== Pathogenicity mechanisms and virulence factors == Burkholderia pseudomallei is an opportunistic pathogen and, since its an environmental organism, has no requirement to pass through an animal host to replicate. From the point of view of the bacterium, human infection is a developmental "dead end". Strains which cause disease in humans differ from those causing disease in other animals, by possessing certain genomic islands. It may have the ability to cause disease in humans via DNA acquired from other microorganisms. Its mutation rate is also high, and the organism continues to evolve even after infecting a host. Burkholderia pseudomallei is able to invade cells - being an intracellular pathogen. It is able to polymerise actin, and to spread from cell to cell, causing cell fusion and the formation of multinucleated giant cells. It possesses a uniquely fusogenic type VI secretion system that is required for cell-cell spread and virulence in mammalian hosts. The bacterium also expresses a toxin called lethal factor 1. B. pseudomallei is one of the first Proteobacteria to be identified as containing an active type VI secretion system. It is also the only organism identified that contains up to six different type VI secretion systems. B. pseudomallei is intrinsically resistant to many antimicrobial agents by virtue of its efflux pump mechanism. This mediates resistance to aminoglycosides (AmrAB-OprA), tetracyclines, fluoroquinolones, and macrolides (BpeAB-OprB).
=== Central nervous system === In general, adenosine has an inhibitory effect in the central nervous system (CNS). Caffeine's stimulatory effects are credited primarily (although not entirely) to its capacity to block adenosine receptors, thereby reducing the inhibitory tonus of adenosine in the CNS. This reduction in adenosine activity leads to increased activity of the neurotransmitters dopamine and glutamate. Experimental evidence suggests that adenosine and adenosine agonists can activate Trk receptor phosphorylation through a mechanism that requires the adenosine A2A receptor. Adenosine in the brain acts through three major receptor subtypes—A1, A2A, and A3—distributed across various neuronal and glial populations. Activation of neuronal A1 receptors generally exerts inhibitory effects, contributing to synaptic regulation. In a preclinical knock-in model of Alzheimer's disease, neuronal hyperexcitability during the asymptomatic stage has been shown to originate at the synaptic compartment and is associated with a deficient adenosinergic tone, suggesting that impaired adenosine signaling may contribute to early synaptic dysfunction.
Sources: en.wikipedia.org
Nanoparticles occur in a great variety of shapes, which have been given many names such as nanospheres, nanorods, nanochains, decahedral nanoparticles, nanostars, nanoflowers, nanoreefs, nanowhiskers, nanofibers, and nanoboxes. The shapes of nanoparticles may be determined by the intrinsic crystal habit of the material, or by the influence of the environment around their creation, such as the inhibition of crystal growth on certain faces by coating additives, the shape of emulsion droplets and micelles in the precursor preparation, or the shape of pores in a surrounding solid matrix. Some applications of nanoparticles require specific shapes, as well as specific sizes or size ranges. Amorphous particles typically adopt a spherical shape (due to their microstructural isotropy).
This basic structure was not touched by the Abbott, Turnbull and Morrison governments, although wages and standards continued to decline through lack of enforcement, growing casualization, and hostile judicial decisions. With the Albanese government, a series of reforms, such as the Fair Work Legislation Amendment (Closing Loopholes) Bill, aimed to raise protection, since Australian labour rights remained significantly below European and wealthier countries' standards. This includes the lack of a restored system for sectoral collective bargaining, weak protection for collective action, and absence of rights for workers to elect directors on boards of enterprises, outside isolated examples in universities or the Australian Broadcasting Corporation, 25 per cent of people on "casual" contracts, and stagnating real wages.
As suggested by the name, the biomass of the mycosymbiont is mostly exterior to the plant root. The fungal structure is composed primarily of three parts: 1) the intraradical hyphae making up the Hartig net; 2) the mantle that forms a sheath surrounding the root tip; and 3) the extraradical hyphae and related structures that spread throughout the soil.
Turnout was 71.42 per cent. Of the 37,807,781 party-list ballots cast, 35,030,601 were valid, 1,669,006 were invalid and 1,108,051 were marked for no party. Bhumjaithai's strength in the constituencies was concentrated geographically. It led the party-list vote in 56 constituencies, compared with 215 for the People's Party, and won no seat in Bangkok, where the People's Party took all 33.
Sources: en.wikipedia.org
The NAD⁺-II riboswitch was first described as the pnuC RNA motif, discovered via computational searches for long GC-rich intergenic regions in bacterial genomes. The original consensus model consists of two base-paired stems (P1 and P1a) separated by a conserved internal loop, with a three-nucleotide segment predicted to form a pseudoknot by base-pairing with a portion of the Shine-Dalgarno sequence of the adjacent open reading frame. Its structure was subsequently confirmed by X-ray crystallography. In contrast to the NAD⁺-I class, NAD⁺-II riboswitches specifically and robustly recognize the oxidized form of the nicotinamide moiety either as part of NMN, NR, or intact NAD⁺. The original examples were found exclusively in the genus Streptococcus, where these riboswitches regulate pnuC genes encoding an NR/NMN transporter. In contrast to the NAD⁺-I class, NAD⁺-II riboswitches specifically and robustly recognize the oxidized form of the nicotinamide moiety either as part of NMN, NR, or intact NAD⁺. The original 43 examples were found exclusively in the genus Streptococcus, where these riboswitches regulate pnuC genes encoding an NR/NMN transporter.
4-Aminosalicylic acid, also known as para-aminosalicylic acid (PAS) and sold under the brand name Paser among others, is an antibiotic primarily used to treat tuberculosis. Specifically it is used to treat active drug resistant tuberculosis together with other antituberculosis medications. It has also been used as a second line agent to sulfasalazine in people with inflammatory bowel disease such as ulcerative colitis and Crohn's disease. It is typically taken by mouth. Common side effects include nausea, abdominal pain, and diarrhea. Other side effects may include liver inflammation and allergic reactions. It is not recommended in people with end stage kidney disease. While there does not appear to be harm with use during pregnancy it has not been well studied in this population. 4-Aminosalicylic acid is believed to work by blocking the ability of bacteria to make folic acid. 4-Aminosalicylic acid was first made in 1902, and came into medical use in 1943. It is on the World Health Organization's List of Essential Medicines.
24. Semaglutide. Drugs and Lactation Database (LactMed®) [Internet]. Bethesda (MD): National Institute of Child Health and Human Development; 2006–. 2026 Aug 15. Semaglutide was not detectable in the milk of mothers taking the drug subcutaneously. Their breastfed infants experienced no adverse effects. Some brands of oral semaglutide, such as Rybelsus, contain the absorption enhancer salcaprozate sodium, which may enter milk and accumulate in infants. Only injectable forms of semaglutide should be used during breastfeeding. Some experts recommend closely monitoring of infant growth and developmental milestones and the nutritional status of the lactating woman.[1]
Sources: en.wikipedia.org
Selank is a synthetic heptapeptide designed as a stabilized analog of the natural tetrapeptide tuftsin. It has been investigated mainly for anxiolytic and cognitive effects. It is not an approved pharmaceutical in most countries.
It was developed in Russia, at the Institute of Molecular Genetics of the Russian Academy of Sciences, during the 1990s. Most published research originates from Russian institutions. Independent international replication remains limited.
Tuftsin is a natural tetrapeptide with the sequence Thr-Lys-Pro-Arg that participates in immune signaling. Selank extends that sequence with Pro-Gly-Pro at the C-terminus. The added residues are linked to greater resistance to enzymatic breakdown.
Reports describe modulation of GABA signalling, changes in monoamine turnover and effects on neurotrophic factor expression. These observations come mainly from animal and cell studies. A single unifying mechanism has not been demonstrated.