selank raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-04-24. Anything still debated is marked as such rather than presented as settled.
Tuftsin, the parent structure, is a naturally occurring immunomodulatory tetrapeptide released from the Fc region of immunoglobulin G by spleen enzymes. Selank extends this four-residue sequence with three additional amino acids. The stated rationale is that the added tail slows enzymatic breakdown and may influence receptor interactions. How the full heptapeptide behaves at the molecular level is not firmly established, and proposed mechanisms often involve indirect modulation of neurotransmitter or immune signaling rather than a single defined target.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Modeled on tuftsin |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Seven residues |
| Approximate molecular mass | Around 750 Da | Depends on counter-ion and hydration |
| Common forms | Lyophilized powder | Also described as aqueous solution |
| Primary origin of research | Russian laboratories | Mid-1990s onward |
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
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.
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.
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.
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.
Romania is a secular state and has no state religion. An overwhelming majority of the population identify themselves as Christians. At the country's 2021 census, 73.60% of respondents identified as Orthodox Christians, with 73.42% belonging to the Romanian Orthodox Church. Other denominations include Protestantism (6.22%), Roman Catholicism (3.89%), and Greek Catholicism (0.61%). From the remaining population 128,291 people belong to other Christian denominations or have another religion, which includes 58,347 Muslims (mostly of Turkish and Tatar ethnicity) and 2,708 Jewish (Jews once constituted 4% of the Romanian population—728,115 persons in the 1930 census). Additionally, 71,430 people are irreligious, 57,229 are atheist, 25,485 are agnostic, and 2,658,165 people chose to not declare their religion. The Romanian Orthodox Church is an autocephalous Eastern Orthodox Church in full communion with other Orthodox churches, with a Patriarch as its leader. It is the third-largest Eastern Orthodox Church in the world, and unlike other Orthodox churches, it functions within a Latin culture and uses a Romance liturgical language. Its canonical jurisdiction covers the territories of Romania and Moldova. Romania has the world's third-largest Eastern Orthodox population.
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=== Antimicrobial peptides and biomembranes === Mechler's research on biomolecular interactions has focused on lipid membranes, their phase and domain dynamics, and membrane disruption by antimicrobial peptides. He utilized spectroscopic imaging and near-field microscopy to show that cholesterol-rich domains in bilayer membranes form optimally at a 15:85 lipid-cholesterol ratio, with specific domain separation occurring at lower concentrations. Additionally, he found that the structure of supported phospholipid bilayers varies with liposome size, composition, and substrate, as shown by quartz crystal microbalance and atomic force microscopy. Working with Imad Younus Hasan, Mechler employed QCM-based measurements to show cholesterol induces phase separation in single bilayer lipid membranes and demonstrated that partially suspended DMPC-based bilayer membranes can form on functionalized gold surfaces in a way that allows natural membrane movement, providing a truly Biomimetic platform for membrane studies and protein insertion. They also mapped thermodynamic phase transitions of lipid membranes, through nanoviscosity measurements, in single bilayer lipid membranes, revealing that domain separation occurs only in planar membranes and that phase transitions are due to the breaking of van der Waals interactions. Using quartz crystal microbalance and atomic force microscopy, Mechler and his research group investigated how specific antimicrobial peptides secreted by insects such as honeybees and amphibians such as Australian tree frogs disrupt bacterial membranes.
== Bibliography == Michel Demopoulos, directeur de publication, Le Cinéma grec [Greek Cinema], Paris, Centre Georges Pompidou, collection «cinéma/pluriel,» 1995, 263 pages, ISBN 2858508135. (in French) Vrasidas Karalis, A History of Greek Cinema, New York, New York and London, Continuum International Publishing Group, 2012, 344 pages, ISBN 978-1-4411-9447-3. Sylvie Rollet, directeur de publication (préface: Theo Angelopoulos), Théorème 9: Théo Angelopoulos au fil du temps [Theo Angelopoulos over the Course of Time], Paris, Presses Sorbonne Nouvelle, 2007, 189 pages, ISBN 978-2-87854-372-8. (in French) Stéphane Sawas, «Grèce (1967–1974) – Les écrans grecs sous la dictature des colonels: la grande rupture,» [Greece (1967–1974) – Greek Screens Under the Dictatorship of the Colonels: The Great Break] dans Raphaël Muller et Thomas Wieder, directeurs de publication, Cinéma et régimes autoritaires au xxe siècle: Écrans sous influence [Cinema and Authoritarian Regimes in the Twentieth Century: Screens Under Influence], Paris, Éditions École Normale Supérieure rue d'Ulm et Presses Universitaires de France, collection «Les rencontres de Normale Sup',» 2008, 285 pages, ISBN 978-2-13-055749-4.
Sources: en.wikipedia.org
== Overdose == LSD at typical recreational doses (~50–250 μg) is considered to be very safe in terms of toxicity, with not a single toxicity-related death having been reported at such doses despite many millions of exposures. In addition, LSD is considered to be a relatively non-toxic drug in overdose. The highest dose of LSD evaluated in clinical trials in humans has been 800 μg (0.8 mg), or 8 times the typical recreational dose of 100 μg. However, other studies reported use of doses of up to 2,000 μg intramuscularly in some individuals, or more than 20 times the typical dose. It is estimated, based on animal studies and human case reports, that the lethal dose of LSD in humans is approximately 100 mg, or 1,000 times the typical dose. There have been a handful of reported cases of fatal overdose with LSD as of 2024. However, critical review of the literature by David E. Nichols found that of five identified cases, one was not consistent with the effects of LSD but instead may have been another drug like 25I-NBOMe; two involved normal doses of LSD in individuals who were placed in maximal physical restraint (hogtied) by police followed by presumed positional asphyxia and fatal cardiovascular collapse (hogtying being a practice that is associated with accidental death generally); and two were associated with massive LSD overdose involving doses of possibly more than 300 mg. Besides death due to toxicity, LSD is rarely associated with death via suicide, accidents, or violent encounters due to induction of abnormal behavior.
== End group removal == Controlled radical polymerization, namely reversible addition−fragmentation chain-transfer polymerization (RAFT), is a common method for the polymerization of acrylates, methacrylates and acrylamides. Usually, a thiocarbonate is used in combination with an effective initiator for RAFT. The thiocarbonate moiety can be functionalized at the R-group for end group analysis. The end group is a result of the propagation of chain-transfer agents during the free-radical polymerization process. The end groups can subsequently be modified by the reaction of the thiocarbonylthio compounds with nucleophiles and ionic reducing agents.
Beginning in the 1990s, the food sector in developing countries has rapidly transformed, particularly in Latin America, South-East Asia, India, China and South Africa. With growth has come considerable competition and some amount of consolidation. The growth has been driven by: increasing affluence and the rise of a middle class; the entry of women into the workforce; a consequent incentive to seek out easy-to-prepare foods; the growth in the use of refrigerators, making it possible to shop weekly instead of daily; and the growth in car ownership, facilitating journeys to distant stores and purchases of large quantities of goods. The opportunities presented by this potential have encouraged several European companies to invest in these markets (mainly in Asia) and American companies to invest in Latin America and China. Local companies also entered the market. Initial development of supermarkets has now been followed by hypermarket growth. In addition there were investments by companies such as Makro and Metro Cash and Carry in large-scale Cash-and-Carry operations. While the growth in sales of processed foods in these countries has been much more rapid than the growth in fresh food sales, the imperative nature of supermarkets to achieve economies of scale in purchasing means that the expansion of supermarkets in these countries has important repercussions for small farmers, particularly those growing perishable crops.
Therefore, it is believed that fermented sake kasu is beneficial against nasal allergies. This may also be a result of its potential to reduce symptoms of inflammation or swelling. Consuming fermented sake kasu can also delay the occurrence of scratching behavior and pathogenesis in NC/Nga mice that are prone to atopic dermatitis.
Until about the time of the Meiji Restoration in 1868, cattle were used only as draught animals, in agriculture, forestry, mining and transport, and as a source of fertilizer. Milk consumption was unknown, and – for cultural and religious reasons – meat was not eaten. Cattle were highly prized and valuable, too expensive for a poor farmer to buy. Japan was effectively isolated from the rest of the world from 1635 until 1854; there was no possibility of the intromission of foreign genes to the cattle population during this time. In western Japan during the Edo period (1603–1867), superior cattle were produced by aggressive inbreeding, and the superior bloodlines were called "tsuru" (蔓, lit. 'vine'), and cattle with superior bloodlines (tsuru-ushi, lit. 'vine cattle') were traded at high prices. Famous tsuru include the Takenotani tsuru (Okayama Prefecture), Bokura tsuru (Shimane Prefecture), Iwakura tsuru (Hiroshima Prefecture), and Shusuke tsuru (Hyōgo Prefecture). In Japan, where meat eating was frowned upon and the use of milk was not widespread, cows in the Edo period were primarily work cattle that plowed the fields, so a good cow in this period meant one that was healthy and obedient.
Sources: en.wikipedia.org
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.
It originates from research in Russia, associated with the Institute of Molecular Genetics of the Russian Academy of Sciences. The first descriptions date to the mid-1990s. Most published studies come from Russian laboratories.
No, Selank itself does not occur naturally. Its backbone is based on tuftsin, which is produced in the body, but the seven-residue version is a synthetic construct. It is supplied as a manufactured peptide.
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.