tuftsin comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-04-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | -20 °C or below | For lyophilized powder, long term |
| Common analytical method | Reverse-phase HPLC | Usually paired with mass spectrometry |
| Typical reported purity | At or above 95 percent by area | Research-grade material |
| Aqueous solubility | High | Solutions used in laboratory assays |
| Moisture sensitivity | Hydrolyzes in solution | Aseptic handling reduces degradation |
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.
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
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.
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.
The reduction and subsequent reoxidation of vitamin K coupled with carboxylation of Glu is called the vitamin K cycle. Humans are rarely deficient in vitamin K because, in part, vitamin K2 is continuously recycled in cells. Warfarin and other 4-hydroxycoumarins block the action of VKOR. This results in decreased concentrations of vitamin K and vitamin K hydroquinone in tissues, such that the carboxylation reaction catalyzed by the glutamyl carboxylase is inefficient. This results in the production of clotting factors with inadequate Gla. Without Gla on the amino termini of these factors, they no longer bind stably to the blood vessel endothelium and cannot activate clotting to allow formation of a clot during tissue injury. As it is impossible to predict what dose of warfarin will give the desired degree of clotting suppression, warfarin treatment must be carefully monitored to avoid underdose and overdose.
On 4 March, at the Extraordinary Arab Summit in Cairo on Developments in the Palestinian Issue, Arab leaders adopted a $53 billion plan proposed by Egypt that did not involve displacing Palestinians from the Strip. The plan was to create an interim committee of "independent, professional Palestinian technocrats" to govern Gaza to prepare for the Palestinian Authority’s return. Hamas said that it would not bring its own candidates to the proposed governing committee but that it would need to give its permission in regards to the committee’s tasks, members and agenda. Mahmoud Abbas said that he would be prepared to hold elections, which Hamas welcomed. The summit released an AI-enhanced presentation showing modern housing developments, as well as blueprints for resorts and attractions. The plan was to seek international funding. The plan outlines a six-month phase of recovery providing temporary housing for 1.5 million displaced Palestinians within seven sites in Gaza, followed by a two-stage reconstruction program: a two-year first stage of $20 billion and a 2.5 year second stage of $30 billion. The New York Times reported the funding for the plan remains unclear as Gulf states will be reluctant to invest in rebuilding Gaza only to see it destroyed again if violence returns. The Israeli foreign ministry said the plan had "outdated" outlooks and rejected the plan's dependence on the Palestinian Authority, adding that Hamas would be given power by the plan.
=== Diet === Diet may be a modifiable risk factor for the development of Alzheimer's disease, but more research needs to be conducted. The Mediterranean diet, and the DASH diet are both associated with less cognitive decline. A different approach has been to incorporate elements of both of these diets into one known as the MIND diet. Results from large-scale epidemiological studies and clinical trials have not demonstrated an independent role for most individual dietary components.
== Further reading == Martino D, Tanner A, Defazio G, et al. (May 2005). "Tracing Sydenham's chorea: historical documents from a British paediatric hospital". Archives of Disease in Childhood. 90 (5): 507–11. doi:10.1136/adc.2004.057679. PMC 1720385. PMID 15851434.
Sources: en.wikipedia.org
Starbucks has faced allegations of anti-union practices in the United States, including allegations of retaliation against employees involved in union organizing. In 2022, over a period of several months, Starbucks terminated more than 85 U.S. workers who had been involved in union organizing. Workers and their union also accused Starbucks of creating a culture of fear and surveillance in its stores. In November 2022, the company announced the closure of a Seattle location that had been the first Starbucks store to unionize in the city, citing safety concerns. In December, workers at more than 100 U.S. stores went on strike over allegations of anti-union practices and working conditions. In December 2024, workers at more than 300 U.S. stores went on strike during the holiday season over stalled contract negotiations concerning wages, staffing, and working conditions. In January 2025, Starbucks and Workers United agreed to use a mediator to help resume stalled negotiations. The union had filed more than 90 unfair labor practice complaints against the company in the preceding weeks. In November 2025, more than 1,000 unionized Starbucks workers in more than 40 U.S. cities began an open-ended strike over stalled contract negotiations. Union organizing and collective bargaining continued into 2026, with Workers United winning representation elections at additional Starbucks locations and new organizing petitions being filed with the National Labor Relations Board.
The Ordre des Palmes académiques (French pronunciation: [ɔʁdʁ de palm(z‿)akademik]; French for 'Order of Academic Palms') is a national order bestowed by the French Republic on distinguished academics and teachers and for valuable service to universities, education and science. Originally established in 1808 by Emperor of the French Napoleon as a decoration to honour eminent members of the University of Paris, it was changed into its current form as an order of merit on 4 October 1955 by President René Coty, making it one of the oldest civil honours bestowed by the French Republic.
=== Mechanism of action === Oclacitinib is not a corticosteroid or antihistamine, but rather modulates the production of signal molecules called cytokines in some cells. Normally, a cytokine binds to a JAK (Janus kinase) receptor, driving the two individual chains to come together and self-phosphorylate. This brings in STAT proteins, which are activated and then go to the nucleus to increase transcription of genes coding for cytokines, thus increasing cytokine production. Oclacitinib inhibits signal JAK family members (JAK1, JAK2, JAK3, and tyrosine kinase 2), most effectively JAK1, while not significantly inhibiting non-JAK kinases.
In 2014, Hart starred as Ben in Ride Along, opposite Ice Cube. The film received generally negative reviews from critics, but was a major box office success. Hart returned in the sequel, Ride Along 2, which was released in 2016. In 2015, Hart starred in the films Get Hard with Will Ferrell and The Wedding Ringer. In 2016, he starred in Central Intelligence with Dwayne Johnson and the animated The Secret Life of Pets. In 2017, he starred in Captain Underpants: The First Epic Movie (in a voice role), and Jumanji: Welcome to the Jungle with Jack Black, Karen Gillan, and reteaming again with Johnson. He earned an estimated $32.5 million in 2017. In 2018, he produced his first film under his production company HartBeat Productions, Night School. In October 2018, his production company announced that he signed a first-look deal with Nickelodeon. Under the deal, Hart and his HartBeat Productions banner will develop and produce live-action, scripted kids content for the network. Hart also has a first-look film deal with Universal Studios. In 2019, Hart's film The Upside, his first headlining role in a drama, was theatrically released. It also starred Bryan Cranston and Nicole Kidman. Hart also reprised his role of Snowball in the sequel The Secret Life of Pets 2, and Franklin Finbar in Jumanji: The Next Level. In 2021, Hart starred in Fatherhood, a drama about a man whose wife dies shortly after childbirth, leaving him to raise their daughter on his own. It premiered on Netflix on June 18, 2021.
where the solubility product for [Ca2+][CO2−3] is given as anywhere from Ksp = 3.7×10−9 to Ksp = 8.7×10−9 at 25 °C, depending upon the data source. What the equation means is that the product of molar concentration of calcium ions (moles of dissolved Ca2+ per liter of solution) with the molar concentration of dissolved CO2−3 cannot exceed the value of Ksp. This seemingly simple solubility equation, however, must be taken along with the more complicated equilibrium of carbon dioxide with water (see carbonic acid). Some of the CO2−3 combines with H+ in the solution according to
Sources: en.wikipedia.org
The most common approach combines reverse-phase liquid chromatography with mass spectrometry. Chromatography separates the components while mass spectrometry confirms the molecular mass. Peptide sequencing or tandem mass analysis can further verify the amino acid order.
Lyophilized powder is usually kept frozen and protected from moisture. Solutions are less stable and are often used promptly or divided into aliquots to avoid repeated freeze-thaw cycles. Exact shelf-life values depend on purity and handling.
No. A purity figure derived from chromatographic area does not prove the amino acid sequence. Identity requires an orthogonal method such as mass spectrometry or sequencing. Truncated or isomerized peptides can co-elute with the target compound.
Dry powder is normally held at -20 degrees Celsius or below in a sealed, light-protected container with desiccant. Brief room-temperature handling during weighing is generally tolerated. Storage instructions vary between suppliers, so the accompanying certificate of analysis should be followed.