A practical reference on Tuftsin analog: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-01-22 and is reviewed periodically as new material appears.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Primary route studied | Intranasal | Also examined parenterally in animal work |
| Reported plasma half-life | Minutes to tens of minutes | Values vary widely between reports |
| Main model systems | Rodent behavioural and cell assays | Human trials are few and small |
| Principal proposed targets | GABA-A receptor, GABA transaminase | Monoamine and neurotrophic pathways also reported |
| Evidence grade | Preliminary | Limited independent replication |
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.
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.
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.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
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.
Selank is not a naturally occurring peptide and has no known endogenous counterpart in human physiology. Russian-language sources frequently call it TP-7, while English-language sources use the name Selank almost exclusively. Database indexing is uneven, partly because early reports appeared in regional journals that are not widely cataloged. Some summaries describe the material as a tuftsin analog and others as a synthetic heptapeptide; the labels overlap rather than conflict. Citing the primary sequence resolves ambiguity more reliably than the research or trade name alone.
Alcohol powder, powdered alcohol or dry alcohol is a powder that becomes an alcoholic drink when water is added. It is made using micro-encapsulation of alcohol (specifically ethanol). In March 2015 four product labels for specific powdered alcohol products were approved by the United States Alcohol and Tobacco Tax and Trade Bureau (TTB) which opened the doors for legal product sales. However, as of 4 January 2016, the product is not yet available for sale and legalization remains controversial due to public-health and other concerns. Researchers have expressed concern that, should the product go into production, increases in alcohol misuse, alcohol use disorder, and associated physical harm to its consumers could occur above what has been historically associated with liquid alcohol alone.
1945 In the US, the Gerontological Society of America is formed. The founder is Edmund Vincent Cowdry. 1950 Largely thanks to the collaborative efforts of Korenchevsky and Cowdry, the International Association of Gerontology is formed, later renamed to the International Association of Gerontology and Geriatrics (IAGG). The organization was registered in Belgium, and that is where its first conference took place. Slowly, gradually, the ideas began to spread that the problems of aging cannot be solved within the framework and efforts of one nation – therefore the international interaction is necessary. 1952 Peter Medawar proposed the mutation accumulation theory to explain how the aging process could have evolved. 1954 Vladimir Dilman formulated the hypothesis of aging that at first become known only in the USSR, as the elevation hypothesis. In 1968 it took the form and became known as the neuroendocrine theory of aging. 1956 Denham Harman proposed the free-radical theory of aging and demonstrated that free radical reactions contribute to the degradation of biological systems. The theory is based on the ideas of Rebeca Gerschman and her colleagues put forward in 1945. 1957 George Williams proposed the antagonistic pleiotropy hypothesis for the explanation of the emergence of aging. 1958 Physicist Gioacchino Failla proposed the hypothesis that aging is caused by the accumulation of DNA damage. The next year the hypothesis was developed by the physicist Leo Szilard, resulting in a number of related theories under the general name DNA damage theory of aging.
== History == Since its discovery in 1967, serine protease DPP-4 has been a popular subject of research. Inhibitors of DPP-4 have long been sought as tools to elucidate the functional significance of the enzyme. The first inhibitors were characterized in the late 1980s and 1990s. Each inhibitor was important to establish an early structure activity relationship (SAR) for subsequent investigation. The inhibitors fall into two main classes, those that interact covalently with DPP-4 and those that do not. DPP-4 is a dipeptidase that selectively binds substrates that contain proline at the P1-position, thus many DPP-4 inhibitors have 5-membered heterocyclic rings that mimic proline, e.g. pyrrolidine, cyanopyrrolidine, thiazolidine and cyanothiazolidine. These compounds commonly form covalent bonds to the catalytic residue Ser630. In 1994, researchers from Zeria Pharmaceuticals unveiled cyanopyrrolidines with a nitrile function group that was assumed to form an imidate with the catalytic serine. Concurrently other DPP-4 inhibitors without a nitrile group were published but they contained other serine-interacting motifs, e.g. boronic acids, phosphonates or diacyl hydroxylamines. These compounds were not as potent because of the similarity of DPP-4 and prolyl oligopeptidase (PEP) and also suffered from chemical instability. Ferring Pharmaceuticals filed for patent on two cyanopyrrolidine DPP-4 inhibitors, which they published in 1995. These compounds had excellent potency and improved chemical stability. In 1995, Edwin B.
D-dimer (or D dimer) is a dimer that is a fibrin degradation product (FDP), a small protein fragment present in the blood after a blood clot is degraded by fibrinolysis. It is so named because it contains two D fragments of the fibrin protein joined by a cross-link, hence forming a protein dimer. D-dimer concentration may be determined by a blood test to help diagnose thrombosis. Since its introduction in the 1990s, it has become an important test performed in people with suspected thrombotic disorders, such as venous thromboembolism. While a negative result practically rules out thrombosis, a positive result can indicate thrombosis but does not exclude other potential causes. Its main use, therefore, is to exclude thromboembolic disease where the probability is low. D-dimer levels are used as a predictive biomarker for the blood disorder disseminated intravascular coagulation and in the coagulation disorders associated with COVID-19 infection. A four-fold increase in the protein is an indicator of poor prognosis in people hospitalized with COVID-19.
They also noticed that the game "goes about fixing a lot of the niggling complaints we had about Episode One," applauding the open forests and rocky hills. The New York Times wrote that "while it sows a few seeds for the final episode of the trilogy, the game lacks the driving force of the previous episode". GameSpy felt that it was less consistent than its predecessors, and that the opening segments were "arguably the weakest".
Sources: en.wikipedia.org
==== Endocrine actions ==== Valproic acid has been found to be an antagonist of the androgen and progesterone receptors, and hence as a nonsteroidal antiandrogen and antiprogestogen, at concentrations much lower than therapeutic serum levels. In addition, the drug has been identified as a potent aromatase inhibitor, and suppresses estrogen concentrations. These actions are likely to be involved in the reproductive endocrine disturbances seen with valproic acid treatment. Valproic acid has been found to directly stimulate androgen biosynthesis in the gonads via inhibition of histone deacetylases and has been associated with hyperandrogenism in women and increased 4-androstenedione levels in men. High rates of polycystic ovary syndrome and menstrual disorders have also been observed in women treated with valproic acid.
While roughly 400 public buildings in Ontario contain RAAC, the Science Centre is currently the only one in the province closed due to these concerns. The Ford government expedited its plan to relocate the Science Centre to the waterfront, targeting a 2028 opening, with a temporary location slated for January 2026. This drew further criticism, including from Moriyama Teshima Architects, the firm founded by the Science Centre's original architect. The architects offered to do pro bono design consulting services for the Government of Ontario to support immediate repairs to the roof, and called for other organizations to join the effort to facilitate repairs. Private donors, including Geoffrey Hinton, offered up to $1 million to fund repairs for the existing facility, but the province did not respond to these offers. By October 31, 2024, most of the exhibits had been moved to storage facilities in northern Toronto and Guelph, while the animals and plants had been transferred to the Toronto Zoo and The Village at Black Creek. Temporary pop-up exhibits have since opened at Sherway Gardens and Toronto's Harbourfront Centre.
=== Blood glucose === Postprandial blood glucose levels become lower after consumption of a meal containing β-glucan as a result of increased gut viscosity, which delays gastric emptying and lengthens travel through the small intestine. In one review, the net decrease in blood glucose absorption reduced postprandial blood insulin concentrations, improving insulin sensitivity. A 2021 meta-analysis of clinical trials concluded that oat beta-glucan with molecular weights greater than 300 kg/mol reduced incremental area-under-the-curve by 23%, peak blood glucose by 28%, and insulin by 22% in a dose-responsive fashion, with similar results in participants with or without diabetes. Diabetic people who increased their daily consumption of beta-glucans by more than 3 grams per day for months also lost body weight.
=== International rail transport resumption === In January 2022, the first freight trains between North Korea and China resumed after a two-year hold. Uiju Air Base was converted to a cargo decontamination facility for containers brought in by freight trains. A South Korean–based humanitarian organisation, the Inter-Korean Economic Cooperation Research Center (남북경제협력연구소, IKECRC), received a UN sanctions exemption to send 20 thermal imaging cameras to North Phyongan province for detection of fever symptoms, while the WHO was granted 18 more months to deliver shipments for stalled projects. In November 2022, use of the rail Korea–Russia Friendship Bridge resumed.
Sources: en.wikipedia.org
== June 22, 1915 (Tuesday) == Gorlice–Tarnów Offensive — German and Austro-Hungarian forces captured Lemberg, effectively ending the offensive as most of Galicia was now back under control of the Central Powers. The Central Powers sustained between 87,000 and 90,000 casualties while Russia sustained eight times that, including 250,000 soldiers taken prisoner. The Imperial German Army created the army groups Centre and East to serve on the Western Front. The Airco DH.2 fighter plane was given an evaluative flight before the model was assigned to the No. 5 Squadron for operational test flights in France. The New York City Subway added three new lines in Brooklyn and Queens: BMT Sea Beach Line with stations Eighth Avenue, Fort Hamilton Parkway, New Utrecht Avenue, 18th Avenue, 20th Avenue, Bay Parkway, Kings Highway, Avenue U, and 86th Street. BMT Fourth Avenue Line in Brooklyn with train stations at Myrtle Avenue, DeKalb Avenue, Atlantic Avenue, Union Street, Ninth Street, Prospect Avenue, 25th Street, 36th Street, and 59th Street. IRT Flushing Line from Vernon Boulevard–Jackson Avenue station in Queens to Grand Central in Manhattan. Ishikawa Electric Railway began operating the Ishikawa Line in the Ishikawa Prefecture, Japan, with stations Shin-Nonoichi, Oshino, Nuka-Jūtakumae, Shijima, Sodani, Dōhōji, Oyanagi, and Tsurugi serving the line. The Leichhardt Bus Depot opened in Sydney as a tram depot before it was converted to a bus depot in 1937.
==== School education ==== Positive psychology is beneficial to schools and students because it encourages individuals to strive to do their best, whereas scolding has the opposite effect. Clifton and Rath discussed research conducted by Dr. Elizabeth Hurlock in 1925, where fourth, fifth and sixth graders were either praised, criticized or ignored, based on their work on math problems. Praised students improved by 71%, those criticized improved by 19%, and students provided with no feedback improved a mere 5%. Praise seems an effective method of fostering improvement. According to Clifton and Rath ninety nine out of one hundred people prefer the influence of positive people. The benefits include: increased productivity, and contagious positive emotions, which assists one in working to the best of their abilities. Even a single negative person can ruin the entire positive vibe in an environment. Clifton and Rath cited 'positive emotions as an essential daily requirement for survival'. In 2008, in conjunction with the Positive Psychology Center at the University of Pennsylvania, a whole-of-school implementation of Positive Psychology was undertaken by Geelong Grammar School (Victoria, Australia). This involved training of teaching staff in the principles and skills of positive psychology. Ongoing support was provided by The Positive Psychology Center staff, who remained in-residence for the entire year. Staats, Hupp and Hagley (2008) used positive psychology to explore academic honesty.
=== Lesbian culture === Violets became symbolically associated with romantic love between women. This connection originates from fragments of a poem by Sappho about a lost love, in which she describes her as "Close by my side you put around yourself [many wreaths] of violets and roses." In another poem, Sappho describes her lost love as wearing "violet tiaras, braided rosebuds, dill and crocus twined around her neck". In 1926, one of the first plays to involve a lesbian relationship, La Prisonnière by Édouard Bourdet, used a bouquet of violets to signify lesbian love.
Sources: en.wikipedia.org
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.
The peptide enters plasma rapidly and is broken down by ordinary proteases into amino acids and shorter fragments. Reported half-lives are short. Whether meaningful amounts of the intact molecule reach the brain is an open question.
Most clinical reports are small, published in Russian and not independently replicated. English-language reviews highlight the absence of large randomised trials. Conclusions about efficacy should be treated as provisional.
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.