Everything below concerns Heptapeptide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-11-06. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| 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 |
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter notation. Its structure consists of the immunomodulatory tetrapeptide tuftsin, Thr-Lys-Pro-Arg, extended at the carboxyl terminus by a Pro-Gly-Pro segment. The molecular formula is commonly given as C33H57N11O9, corresponding to a monoisotopic mass near 751.4 Da and an average molecular mass near 751.9 Da. All seven residues are proteinogenic amino acids, and the molecule carries no modified side chains or non-natural linkages.
The compound was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences during the 1980s and 1990s. The stated design goal was to retain the immunomodulatory and central nervous system activity attributed to tuftsin while improving resistance to enzymatic breakdown. Adding a proline-rich tail to the short parent peptide was a deliberate strategy, because proline residues restrict the conformations available to many peptidases. The same laboratory produced Semax, an ACTH fragment analog, and both compounds were developed in parallel as short, enzymatically stabilized peptides intended for intranasal use.
Peptide bonds are vulnerable to protease attack, and Selank is no exception. Measured half-life in serum is short, on the order of minutes in several reports, which explains why intranasal administration is the common route described in the literature. Absorption across the nasal mucosa partially bypasses first-pass hepatic metabolism. Quantitative data on human bioavailability remain limited and are difficult to compare across studies.
Lyophilised material kept dry at minus 20 degrees Celsius or colder is the most stable form, and suppliers commonly state a shelf life of two years or more under those conditions. Once dissolved, degradation accelerates through hydrolysis and deamidation, particularly at alkaline pH or elevated temperature. Working solutions are usually divided into single-use aliquots to avoid repeated freeze-thaw cycles. The choice of reconstitution solvent affects both stability and the ionic strength of the final preparation.
=== Metabolic pathways === Genomic analysis indicates that "Ca. M. multicellularis" has the potential to use both autotrophic and heterotrophic pathways. For autotrophic growth, it utilises the Wood–Ljungdahl pathway (also known as the reductive acetyl-coenzyme A pathway) for carbon fixation. For heterotrophy, it is able to use small organic molecules including acetate, propionate, and succinate as carbon donors and/or electron sources. "Ca. M. multicellularis" has also been found to contain a complete glycolysis pathway, a full TCA cycle and group-1 nickel-iron hydrogenases coupled to oxidative phosphorylation. As found in SCM sequencing, the consortium exhibits both genetic and metabolic differentiation. The use of nano-scale secondary ion mass spectrometry (NanoSIMS) and bioorthogonal noncanonical amino acid tagging (BONCAT) demonstrated that anabolic activity and protein synthesis is not uniform across the organism. The most active regions of protein synthesis were found to be concentrated around the acellular centre. A 2024 study suggests the potential for an internal division of labour, with certain cells metabolising specific substrates and transferring them to surrounding cells by membrane vesicles.
Independent research: this would be work done with core or flexible funding that allows the researchers the liberty to choose their research questions and method. It may be long term and could emphasize 'big ideas' without direct policy relevance. However, it could emphasize a major policy problem that requires a thorough research and action investment. Consultancy: this would be work done by commission with specific clients and addressing one or two major questions. Consultancies often respond to an existing agenda. Influencing/advocacy: this would be work done by communications, capacity development, networking, campaigns, lobbying, etc. It is likely to be based on research based evidence emerging from independent research or consultancies. Second, policy institutes may base their work or arguments on:
The excess of said expense, compared to the average cost of neighboring countries, was close to 0.79% of GDP. A Fedesarrollo study stated that the spending on defense and security carried out during 2004 "represented 4.5% of GDP", which does not have precedents in the history of Colombia. This is directly related to the Democratic Security Policy (Política de seguridad democrática) undertaken by the government of then-president Álvaro Uribe, who focused on military strikes on groups outside the law in order to regain security national. For the year 2004, the expenses of the Colombian Government in war and security were 6.59%, placing the country between the tenth that invest the most in war as a proportion of GDP.
Sources: en.wikipedia.org
Thiopental is a barbiturate with one of the C=O double bonds (with the carbon being labelled 2 in the adjacent diagram) replaced with a C=S double bond, R1 being CH2CH3 (ethyl) and R3) being CH(CH3)CH2CH2CH3 (sec-pentyl). Thiopental is no longer available in the United States.
Following the 1494 Treaty of Tordesillas, the land now called Brazil was claimed for the Portuguese Empire on 22 April 1500, with the arrival of the Portuguese fleet commanded by Pedro Álvares Cabral. Along the coast, the Portuguese encountered various Indigenous communities, most of whom spoke languages of the Tupi–Guarani family. Though the first settlement, São Vicente, was founded in 1532, colonization effectively began in 1534, when King John III of Portugal divided the territory into the fifteen private and autonomous captaincies. However, the decentralized and unorganized captaincy system proved unsuccessful, and in 1549 the Portuguese king restructured them into the Governorate General of Brazil in the city of Salvador, which became the capital of a single and centralized Portuguese colony in South America. In the first two centuries of colonization, Indigenous and European groups lived in constant war, establishing opportunistic alliances in order to gain advantages against each other.
== Allegations and events leading up to the arrests == In the spring of 2022, Belgian security services mounted a surveillance operation against former MEP Antonio Panzeri, following a tip-off from another European intelligence service that he had been accepting bribes from Morocco. Information was passed on to the federal prosecutor's office, which opened an investigation in July 2022. According to the testimony of Francesco Giorgi, since 2019, Qatar has funneled cash to Antonio Panzeri. Panzeri, a former member of the European Parliament, and Eva Kaili, a sitting member, were trying to influence voting at the European Parliament in favour of Qatar. Bribes related to Qatar, as well as the Mauritanian government, were, according to Giorgi, channeled through a Brussels-based organization co-founded by Panzeri called Fight Impunity. Iqbal Survé, a controversial businessman from South Africa, was found to be the largest donor to Fight Impunity via his Sekunjalo Development Foundation. Survé's foundation made a donation of €250,000 to the lobbying group between July and September 2020. Belgian authorities are investigating a broader scheme, aimed at influencing decisions by the European Parliament in favour of Qatar. Panzeri's testimony contradicts that of Giorgi, who is Kaili's partner and a former parliamentary advisor to Panzeri, in certain aspects. In his leaked interview with Belgian authorities, Panzeri claimed that the first cash payments came from Morocco, prior to Qatar's involvement.
Sources: en.wikipedia.org
A reading frame is defined by the initial triplet of nucleotides from which translation starts. It sets the frame for a run of successive, non-overlapping codons, which is known as an "open reading frame" (ORF). For example, the string 5'-AAATGAACG-3' (see figure), if read from the first position, contains the codons AAA, TGA, and ACG; if read from the second position, it contains the codons AAT and GAA; and if read from the third position, it contains the codons ATG and AAC. Every sequence can, thus, be read in its 5' → 3' direction in three reading frames, each producing a possibly distinct amino acid sequence: in the given example, Lys (K)-Trp (W)-Thr (T), Asn (N)-Glu (E), or Met (M)-Asn (N), respectively (when translating with the vertebrate mitochondrial code). When DNA is double-stranded, six possible reading frames are defined, three in the forward orientation on one strand and three reverse on the opposite strand. Protein-coding frames are defined by a start codon, usually the first AUG codon in the RNA, (ATG in DNA) sequence. In eukaryotes, open reading frames in exons are often interrupted by introns.
The result of the Jeddah talks was an Iraqi demand for $10 billion to cover the lost revenues from Rumaila. Kuwait offered $500 million. The Iraqi response was to immediately order an invasion, which started on 2 August 1990 with the bombing of Kuwait's capital, Kuwait City. Before the invasion, the Kuwaiti military was believed to have numbered 16,000 men, arranged into three armored, one mechanized infantry and one under-strength artillery brigade. The pre-war strength of the Kuwait Air Force was around 2,200 Kuwaiti personnel, with 80 fixed-wing aircraft and 40 helicopters. In spite of Iraqi sabre-rattling, Kuwait did not mobilize its force; the army had been stood-down on 19 July, and during the Iraqi invasion many Kuwaiti military personnel were on leave. By 1988, at the end of the Iran–Iraq war, the Iraqi Army was the world's fourth largest army, consisting of 955,000 standing soldiers and 650,000 paramilitary forces in the Popular Army. A low estimate shows the Iraqi Army capable of fielding 4,500 tanks, 484 combat aircraft and 232 combat helicopters. A high estimate shows the Iraqi Army capable of fielding one million troops and 850,000 reservists, 5,500 tanks, 3,000 artillery pieces, 700 combat aircraft and helicopters; it held 53 divisions, 20 special-forces brigades, and several regional militias, and had a strong air defense.
== In popular culture == In Winter Light (1963), directed by Ingmar Bergman, the church sexton Algot Frövik was modeled on prop master K.A. Bergman, whose Bekhterev's disease (ankylosing spondylitis) served as the basis for the character's illness. The Oxbow Cure (2013) follows Lena, a woman recently diagnosed with ankylosing spondylitis as she comes to terms with the disease while living in rural Ontario.
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 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.