This is a working overview of tuftsin, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-09-15. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| 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 |
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.
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.
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.
In the famous Monty Python "Spam" sketch Bromley was stated to be the location of the fictional Green Midget Café, where every item on the menu was composed of spam in varying degrees. In another Monty Python sketch, it was stated that all seven continents are visible from the top of the Kentish Times building in Bromley. The Bromley Contingent was the name given to the entourage that followed the Sex Pistols and helped popularise the punk movement. It was so called because many of its members were from Bromley, some of whom later became famous as musicians in their own right, like Siouxsie Sioux and Billy Idol. The 2018 comedy film, The Bromley Boys is set in Bromley and surroundings in the late 1960s and early 1970s. Based on a real-life memoir by Dave Roberts about following Bromley F.C., it includes many scenes filmed locally, although Crockenhill F.C. was used as a substitute for the Hayes Lane stadium. Guitarist Billy Jenkins, born in Bromley, released an album titled "Sounds like Bromley" in 1982 and another in 1997 titled "Still Sounds Like Bromley". In a BBC Radio 3 interview he said that "if Kent is the Garden of England then Bromley is one of the compost heaps". He then moved to Lewisham.
=== Redox === Graphene oxide can be reversibly reduced and oxidized via electrical stimulus. Controlled reduction and oxidation in two-terminal devices containing multilayer graphene oxide films are shown to result in switching between partly reduced graphene oxide and graphene, a process that modifies electronic and optical properties. Oxidation and reduction are related to resistive switching.
=== Poroelasticity === Poroelasticity is a characteristic of materials related to the migration of solvent through a porous material and the concurrent deformation that occurs. Poroelasticity in hydrated materials such as hydrogels occurs due to friction between the polymer and water as the water moves through the porous matrix upon compression. This causes a decrease in water pressure, which adds additional stress upon compression. Similar to viscoelasticity, this behavior is time dependent, thus poroelasticity is dependent on compression rate: a hydrogel shows softness upon slow compression, but fast compression makes the hydrogel stiffer. This phenomenon is due to the friction between the water and the porous matrix is proportional to the flow of water, which in turn is dependent on compression rate. Thus, a common way to measure poroelasticity is to do compression tests at varying compression rates. Pore size is an important factor in influencing poroelasticity. The Kozeny–Carman equation has been used to predict pore size by relating the pressure drop to the difference in stress between two compression rates. Poroelasticity is described by several coupled equations, thus there are few mechanical tests that relate directly to the poroelastic behavior of the material, thus more complicated tests such as indentation testing, numerical or computational models are utilized. Numerical or computational methods attempt to simulate the three dimensional permeability of the hydrogel network.
Sources: en.wikipedia.org
Early British political support for an increased Jewish presence in the region of Palestine was based upon geopolitical calculations. This support began in the early 1840s and was led by Lord Palmerston, following the occupation of Syria and Palestine by separatist Ottoman governor Muhammad Ali of Egypt. French influence had grown in Palestine and the wider Middle East, and its role as protector of the Catholic communities began to grow, just as Russian influence had grown as protector of the Eastern Orthodox in the same regions. This left Britain without a sphere of influence, and thus a need to find or create their own regional "protégés". These political considerations were supported by a sympathetic evangelical Christian sentiment towards the "restoration of the Jews" to Palestine among elements of the mid-19th-century British political elite – most notably Lord Shaftesbury. The British Foreign Office actively encouraged Jewish emigration to Palestine, exemplified by Charles Henry Churchill's 1841–1842 exhortations to Moses Montefiore, the leader of the British Jewish community. Such efforts were premature, and did not succeed; only 24,000 Jews were living in Palestine on the eve of the emergence of Zionism within the world's Jewish communities in the last two decades of the 19th century. With the geopolitical shakeup occasioned by the outbreak of the First World War, the earlier calculations, which had lapsed for some time, led to a renewal of strategic assessments and political bargaining over the Middle and Far East.
=== Parallel MRI === It takes time to gather MRI data using sequential applications of magnetic field gradients. Even for the most streamlined of MRI sequences, there are physical and physiologic limits to the rate of gradient switching. Parallel MRI circumvents these limits by gathering some portion of the data simultaneously, rather than in a traditional sequential fashion. This is accomplished using arrays of radiofrequency (RF) detector coils, each with a different 'view' of the body. A reduced set of gradient steps is applied, and the remaining spatial information is filled in by combining signals from various coils, based on their known spatial sensitivity patterns. The resulting acceleration is limited by the number of coils and by the signal to noise ratio (which decreases with increasing acceleration), but two- to four-fold accelerations may commonly be achieved with suitable coil array configurations, and substantially higher accelerations have been demonstrated with specialized coil arrays. Parallel MRI may be used with most MRI sequences. After a number of early suggestions for using arrays of detectors to accelerate imaging went largely unremarked in the MRI field, parallel imaging saw widespread development and application following the introduction of the simultaneous acquisition of spatial harmonics (SMASH) technique in 1996–7. The sensitivity encoding (SENSE) and generalized autocalibrating partially parallel acquisitions (GRAPPA) techniques are the parallel imaging methods in most common use today.
== History == The presence of autoantibodies against citrullinated proteins in rheumatoid arthritis patients was first described in the mid-1970s when the biochemical basis of antibody reactivity against keratin and filaggrin was investigated. Subsequent studies demonstrated that autoantibodies from RA patients react with a series of different citrullinated antigens, including fibrinogen, deiminated Epstein–Barr virus nuclear antigen 1 and vimentin, which is a member of the intermediate filament family of proteins. Several assays for detecting ACPAs were developed in the following years, employing mutated citrullinated Vimentin (MCV-assay), filaggrin-derived peptides (CCP-assay) and viral citrullinated peptides (VCP-assay). A 2006 clinical study showed that anti viral citrullinated peptide (VCP) antibodies of the IgG and IgA isotypes represent a discriminating specific marker of rheumatoid arthritis from other chronic arthritides and disease controls, suggesting an independent production of each isotype. In 2010, ACPA testing has become substantial part of The 2010 ACR-EULAR classification criteria for rheumatoid arthritis.
In sponges, the mesenchyme is called mesohyl. In diploblasts (Cnidaria and Ctenophora), the mesenchyme is fully ectodermally derived. This kind of mesenchyme is called ectomesodermal, and is not considered true mesoderm. In triploblastic acoelomates (such as flatworms), the term parenchyma is sometimes used for the middle (mesenchymal) layer, in which the dense layer includes tissues derived from both ectoderm, and entomesoderm (true mesoderm, derived from entoderm). When cellular material is sparse or densely packed, as in cnidarians, the mesenchyme may sometimes be called collenchyma, or parenchyma in flatworms. When no cellular material is present as in Hydrozoa, the layer is properly called mesoglea. In some colonial cnidarians, the mesenchyme is perforated by gastrovascular channels continuous among colony members. This entire matrix of common basal material is called coenenchyme.
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.
Purity is usually reported as an HPLC area percentage, most often measured at 214 nm. Identity is confirmed separately by mass spectrometry. A certificate of analysis should state both the method and the observed value.