Everything below concerns nootropic. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-04-10. Where a claim depends on a specific study, the study is described rather than over-claimed.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Reported pharmacological effects center on reduced anxiety-like behavior in animal models and on measures of memory and learning. Proposed contributing mechanisms include modulation of GABAergic signaling, shifts in monoamine turnover, and changes in the activity of enzymes that degrade neuropeptides. Effects on the expression of genes linked to neuroplasticity have also been described. No single molecular target is widely accepted, and whether the behavioral findings arise from one pathway or several remains an open question.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Derived from the seven-residue sequence |
| Molecular weight | About 751.9 g/mol | Average mass; the monoisotopic value is slightly lower |
| Residue count | Seven amino acids | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Parent compound | Tuftsin (Thr-Lys-Pro-Arg) | Selank extends tuftsin at the C-terminus |
| Compound class | Synthetic short peptide | Studied in a research setting; not a licensed drug in most markets |
Laboratory work relies on standard behavioral paradigms. Rodents are tested in the elevated plus maze, open field, and passive avoidance tasks, with outcomes compared against diazepam or vehicle controls. Intranasal dosing is used most often because it bypasses first-pass metabolism, though intraperitoneal and intravenous routes also appear in published protocols. Biochemical endpoints include tissue BDNF concentrations, cytokine levels, and monoamine metabolites. Human data are limited to small Russian trials reporting reduced anxiety scores; most were not prospectively registered, and few employed independent outcome assessment.
Measuring peptide exposure inside the brain is technically difficult. Selank is degraded rapidly in plasma, and assays must separate intact peptide from fragments, which favors targeted mass spectrometry over immunoassays alone. Reported half-lives are short, on the order of minutes, so effects observed hours later are attributed to downstream signaling rather than to the parent compound. Blood-brain barrier permeability is debated and rarely quantified directly. Gaps include absent dose-response characterization, inconsistent reporting of purity, and almost no pharmacokinetic data from human participants.
Selank is studied chiefly as an animal-model anxiolytic with proposed secondary effects on memory and immune signaling. Reported mechanisms include modulation of the GABA-A receptor complex, inhibition of enkephalin-degrading enzymes, and shifts in monoamine turnover within limbic structures. Some experiments describe increased expression of brain-derived neurotrophic factor in the hippocampus after repeated dosing. No single molecular target has been confirmed, and the peptide does not bind any receptor with the selectivity typical of a conventional small-molecule drug. Mechanism therefore remains a set of hypotheses rather than an established pathway.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Quality assessment of Selank samples typically combines purity determination with identity confirmation and counter-ion analysis. Purity is usually reported as a percentage by chromatographic area, with values above 95 percent often quoted for research-grade material. Water content and residual solvents are checked in lyophilized batches because they affect both stability and accurate mass determination. A reported purity figure does not by itself establish that a sample is the intended sequence, so orthogonal methods are needed to rule out sequence isomers or truncation products.
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
Due to its property of being a prodrug of GHB which increases sleep related growth hormone (GH) secretion, GBL was sold as a nutritional supplement after the scheduling of GHB, under the names Revivarant and Renewtrient, until they were banned by the FDA.
In March 1945, he gave key cabinet positions to Czechoslovak communist exiles in Moscow. Especially after the German reprisals for the assassination of Reinhard Heydrich, most of the Czech resistance groups demanded, with eerie irony and based on Nazi terror during the occupation, ethnic cleansing or the "final solution of the German question" (Czech: konečné řešení německé otázky) which would have to be "solved" by deportation of the ethnic Germans from their homeland. These reprisals included massacres in villages Lidice and Ležáky, although these villages were not connected with Czech resistance. These demands were adopted by the government-in-exile, which sought the support of the Allies for this proposal, beginning in 1943. During the occupation of Czechoslovakia, the Government-in-Exile promulgated a series of laws that are now referred to as the "Beneš decrees". One part of these decrees dealt with the status of ethnic Germans and Hungarians in postwar Czechoslovakia, and laid the ground for the deportation of some 3,000,000 Germans and Hungarians from the land that had been their home for centuries (see expulsion of Germans from Czechoslovakia, and Hungarians in Slovakia). The Beneš decrees declared that German property was to be confiscated without compensation. However, the final agreement authorizing the forced population transfer of the Germans was not reached until 2 August 1945 at the end of the Potsdam Conference.
DavePhos, the first reported dialkylbiaryl phosphine ligand, was initially used in Pd-catalyzed Suzuki-Miyaura cross-coupling reactions as well as Buchwald-Hartwig aminations. Complexes of this ligand also catalyze a wide array of reactions, including the arylation of ketones and esters, borylation of aryl chlorides, and the arylation of indoles. Many modified versions of DavePhos have been synthesized. t-BuDavePhos has been shown to be an even more reactive variant of DavePhos in the room temperature Suzuki-Miyaura coupling of aryl bromides and chlorides. The biphenyl equivalent (PhDavePhos) is also available.
Sources: en.wikipedia.org
== Types == Hydroquinone is a commonly used agent in skin whiteners. The European Union banned it from cosmetics in 2000. It works by decreasing melanin production. Tretinoin, also known as all-trans retinoic acid, may be used to whiten specific areas. It may be used in combination with steroids and hydroquinone. Alpha hydroxy acid (AHA) is used as a skin bleacher. Its biochemical mechanism is unclear. Side effects may include sun sensitivity, skin redness, thickening, or itching. Low concentrations may be used in cosmetics. Kojic acid has been found to be an effective lightener in some studies and is also allowed to be used in cosmetics. Side effects include redness and eczema. Glutathione is the most common agent taken by mouth to whiten the skin. It can be used as a cream. It is an antioxidant normally made by the body. Whether or not it actually works is unclear as of 2019. Due to side effects that may result from intravenous use, the government of the Philippines recommends against such use. One 2017 review found tentative evidence of benefit of tranexamic acid in melasma. Another 2017 review found that evidence to support its use was insufficient. Azelaic acid may be a second-line option for melasma. Decapaptide-12 and related peptides which act as tyrosinase inhibitors have been used as skin-lightening agents. A number of types of laser treatments have been used in melasma with some evidence of benefit. Reoccurrence is common, and certain types of lasers can result in more pigmentation.
== Early life == Lamont Bentley was born in Milwaukee, Wisconsin on October 25, 1973, the son of Donald Gardison and Loyce Bentley. Lamont grew up on Milwaukee's north side of town and attended Webster Middle School. He moved to Los Angeles with his mother, who wished to pursue a career as a professional singer.
Adjuvants may make vaccines too reactogenic, which often leads to fever. This is often an expected outcome upon vaccination and is usually controlled by oral paracetamol if necessary. Some more severe adverse effects that may exist are: Aluminium salts used in many human vaccines are regarded as safe by Food and Drug Administration. Aluminum has been suspected to play a role in the development of Alzheimer's disease (AD) ever since 1910 (the modern hypothesis dates to 1965); if there is a link between Al and AD, some concern about intentionally injecting aluminum would be reasonable. However, this "aluminum hypothesis" is not accepted by mainstream AD researchers: the evidence for aluminum having such an effect is scarce and weak compared to the evidence against such an idea. This theory is treated with great disinterest in the mainstream as there's no point in testing something that has failed almost every test. The aluminum hypothesis is one of the medical theories that has wider public acceptance than among professions. About one in 100,000 French people who receive aluminum adjuvants are diagnosed with macrophagic myofasciitis (MMF). When treated as a medical condition, MMF has symptoms such as muscle pain and fever. Many people who have these symptoms have the "MMF lesion", where an aluminum deposit seems to be causing a perpetual cycle of macrophages ingesting Al and dying from it, though it remains debated whether the two things have a link. It can be treated by a surgery that removes the deposit.
=== Evidence === At trial, the prosecution presented evidence from parents, clinicians and expert witnesses. The mother of Baby E testified that she had heard her son cry and found blood around his mouth while Letby was present; Letby attributed the blood to a nasogastric tube. Baby E died later that day. Letby subsequently sent a sympathy card to the family, photographs of which were later found on her phone. The court also heard that she had been advised more than once not to enter a room where bereaved parents were grieving. Prosecutors cited text messages sent by Letby to colleagues, which they said showed inappropriate interest in clinical events. Messages included offers to take additional intensive‑care shifts shortly after deaths or collapses, expressions of frustration when not allocated to intensive‑care rooms, and comments about fate following a series of deaths. The court also heard that Letby had searched for the families of several infants on Facebook, sometimes on anniversaries or significant dates. She told the jury this reflected general curiosity and frequent phone use. Consultants testified that they believed suspicious incidents began after Letby qualified to work in intensive care in 2015 and that the pattern of collapses shifted after she was moved from night to day shifts in 2016. One consultant said he had found Letby standing over a deteriorating infant in February 2016 and believed she had not intervened promptly; the infant survived.
Sources: en.wikipedia.org
== Overview == VersaCold started in 1946 as B.C. Ice & Cold Storage Co., serving Vancouver’s fishing industry. In the decades that followed, the company expanded steadily east. By the 1980s the company had established a strong base in the West with eight facilities in BC, Alberta and Washington. A series of mergers and acquisitions throughout the 1990s put VersaCold on the continental and, by 2005, global map, as the purchase of P&O Cold Storage added operations in the US, Australia, New Zealand and Argentina. In 2010, VersaCold sold its offshore operations and returned to its Canadian roots. VersaCold is jointly owned by Toronto-based private equity firm KingSett Capital and Quebec-based investor Ivanhoé Cambridge. Today, VersaCold operates the largest temperature-sensitive logistics network in Canada, with 27 temperature-controlled warehouses and distribution centres and a fleet of trucks providing local, regional, national and international transportation across Canada and the United States. In August 2022, American multinational logistics chain Lineage announced its acquisition of VersaCold for an undisclosed sum.
== External links == IRAC website home page Ralf Nauen, PhD IRAC Chairman (September 2012). "Activities of the Insecticide Resistance Action Committee (IRAC)" (PDF). EPPO Resistance Panel Meeting, Paris. Archived from the original (PDF) on 2015-06-05. Retrieved 2017-06-21. Insecticide Resistance Management from IRAC on YouTube
=== Regular packing === Nanoparticles of sufficiently uniform size may spontaneously settle into regular arrangements, forming a colloidal crystal. These arrangements may exhibit original physical properties, such as observed in photonic crystals.
Sources: en.wikipedia.org
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, designed as a metabolically stabilized analogue of the endogenous tetrapeptide tuftsin. It has been studied mainly against anxiety-related and cognitive endpoints rather than as an approved medicine in most jurisdictions.
Tuftsin contains four residues, while selank carries an additional Pro-Gly-Pro segment at the carboxyl end. That extension is intended to reduce enzymatic cleavage. Comparative pharmacokinetic data in humans remain limited.
No single receptor target is widely accepted as the definitive mediator of the reported effects. Proposed contributors include GABAergic modulation, shifts in monoamine turnover, and altered neuropeptide degradation. The mechanism is treated in the literature as unresolved.
Selank is a synthetic peptide made of seven amino acids. It is modeled on tuftsin, a natural tetrapeptide, with an added three-residue tail. It is not a small-molecule drug.