The short version of amino acid sequence fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-03-18. 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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences as a structural analogue of tuftsin, a naturally occurring tetrapeptide fragment of the immunoglobulin heavy chain. The added Pro-Gly-Pro tail was intended to slow enzymatic degradation and extend biological activity. In Russia it is registered as an anxiolytic nasal preparation, while regulators elsewhere have not approved it for clinical use.
Proposed mechanisms centre on modulation of the GABAergic system, with reports of altered expression of genes related to GABA-A receptor subunits and changed monoamine turnover. Some studies describe inhibition of enkephalinase, the enzyme that degrades endogenous enkephalins, which may prolong opioid peptide signalling. Effects on brain-derived neurotrophic factor and on cytokine expression have also been reported. These findings come largely from animal models and small human studies, and the precise primary target remains unresolved.
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
| 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 |
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
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.
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.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
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.
== Adverse effects == GLP-1 agonists' most common adverse effects are gastrointestinal. These limit the maximum tolerated dose and require gradual dose escalation. Nausea, vomiting, diarrhea, and constipation are commonly reported. Nausea is directly related to serum concentration and is reported in up to three-quarters of people using short-acting GLP-1 agonists, but fewer of those using long-acting agonists. Injection site reactions are common, especially with shorter-acting drugs. GLP-1 agonists appear to increase the risk of non-arteritic anterior ischemic optic neuropathy. Some people develop anti-drug antibodies, which are more common with exenatide (the antibodies were detectable in a third or more of people) than other GLP-1 agonists and can decrease efficacy. Gallstones may form while attempting to induce rapid weight loss. The risk of aspiration under anesthesia is higher due to delayed gastric emptying, according to case reports. In 2024, the American Society of Anesthesiologists and others suggested suspending GLP-1 agonist treatment in most people on the day of the procedure for daily dosing or a week before for weekly dosing. A 2024 study suggested that GLP-1 weight-loss medications do not increase the risk of suicide or suicidal thoughts in children and adolescents, contrary to some previous concerns. The study included over 54,000 U.S. adolescents and reported a 33% reduction in the risk of suicidal thoughts and attempts among those using the drugs compared to those who did not.
== Further reading == Kelly, Evelyn B. (2013-01-07). Encyclopedia of Human Genetics and Disease [2 volumes]. ABC-CLIO. ISBN 9780313387142. Carakushansky, Gerson; Ribeiro, Marcia Gonçalves; Kahn, Evelyn (2011). "Moderately progressive Ullrich congenital muscular dystrophy". Jornal de Pediatria. 88 (1): 93–96. doi:10.2223/JPED.2112. ISSN 0021-7557. PMID 22016142. "National Guideline Clearinghouse | Evidence-based guideline summary: evaluation, diagnosis, and management of congenital muscular dystrophy: report of the Guideline Development Subcommittee of the American Academy of Neurology and the Practice Issues Review Panel of the American Association of Neuromuscular and Electrodiagnostic Medicine". www.guideline.gov. Archived from the original on 2016-04-08. Retrieved 2016-05-12. Hicks, D.; Lampe, A. K.; Laval, S. H.; Allamand, V.; Jimenez-Mallebrera, C.; Walter, M. C.; Muntoni, F.; Quijano-Roy, S.; Richard, P.; Straub, V.; Lochmuller, H.; Bushby, K. M. D. (16 November 2008). "Cyclosporine A treatment for Ullrich congenital muscular dystrophy: a cellular study of mitochondrial dysfunction and its rescue" (PDF). Brain. 132 (1): 147–155. doi:10.1093/brain/awn289. PMID 19015158. Retrieved 12 May 2016.
Difficulty staying awake Mental confusion Impaired motor functions Impaired reflexes Impaired coordination Impaired balance Dizziness Respiratory depression Low blood pressure Coma Death Coma can be cyclic, with the individual alternating from a comatose state to a hyper-alert state of consciousness, which occurred in a four-year-old boy who overdosed on clonazepam. The combination of clonazepam and certain barbiturates (for example, amobarbital), at prescribed doses has resulted in a synergistic potentiation of the effects of each drug, leading to serious respiratory depression. Overdose symptoms may include extreme drowsiness, confusion, muscle weakness, and fainting.
Sources: en.wikipedia.org
government experiment that infected hundreds of Guatemalans with syphilis". A previous suit against the United States government was dismissed in 2011 for the Guatemala syphilis experiments when a judge determined that the U.S. government could not be held liable for actions committed outside of the U.S. An experiment was conducted by Vanderbilt University in the 1940s where they gave 800 pregnant women radioactive iron, 751 of which were pills, without their consent. In a 1969 article published in the American Journal of Epidemiology, it was estimated that three children had died from the experiment.
== Nanotechnology applications == Many potential applications have been suggested in literature, including enzyme immobilization, drug delivery systems, and nanotechnological self-assembly of materials. Though DNA is not the natural choice for building active structures for nanorobotic applications, due to its lack of structural and catalytic versatility, several papers have examined the possibility of molecular walkers on origami and switches for algorithmic computing. The following paragraphs list some of the reported applications conducted in the laboratories with clinical potential. In a study conducted by a group of scientists from iNANO center and CDNA Center at Aarhus university, researchers were able to construct a small multi-switchable 3D DNA Box Origami. The proposed nanoparticle was characterized by AFM, TEM and FRET. The constructed box was shown to have a unique reclosing mechanism, which enabled it to repeatedly open and close in response to a unique set of DNA or RNA keys. The authors proposed that this "DNA device can potentially be used for a broad range of applications such as controlling the function of single molecules, controlled drug delivery, and molecular computing."
=== Chinese public and the trade === Public concerns have resulted in demand and egg prices falling throughout the country. Prices at a large Beijing wholesale market dropped 10%, and prices fell by 10% the day after news of the contamination broke in Hong Kong. Wholesalers have refused to stock products without melamine inspection certificates. The Beijing Youth Daily reported that farmers had been forced to slaughter tens of thousands of chickens. In 2008, Zhao Lianhai (赵连海), a Chinese man whose son was sickened by tainted milk earlier that year, started a website called "Home for the Kidney Stone Babies" (结石宝宝之家, jieshibaobao.com), which helped families with children affected by tainted milk share their experiences, in part by maintaining a database of medical records. The website upset Chinese authorities, who detained Zhao in November 2009 and arrested him in December 2009.
STE20/SPS1-related proline-alanine-rich protein kinase is an enzyme that in humans is encoded by the STK39 gene. This gene encodes a serine/threonine kinase that is thought to function in the cellular stress response pathway. The kinase is activated in response to hypotonic stress, leading to phosphorylation of several cation-chloride-coupled cotransporters. The catalytically active kinase specifically activates the p38 MAP kinase pathway, and its interaction with p38 decreases upon cellular stress, suggesting that this kinase may serve as an intermediate in the response to cellular stress. Some studies suggest that this gene might be linked to high blood pressure.
Sources: en.wikipedia.org
Becky's absence is written as her dropping out of high school to elope with Mark and moving to Minneapolis. Producers, however, wanted the character to return but, with Goranson unavailable, they recast the role with Canadian actress Sarah Chalke. Chalke appeared as Becky starting mid-Season 6 and all of Season 7. Goranson returned as Becky for Season 8. When Goranson's school schedule occasionally conflicted with her filming schedule, Chalke filled in. Goranson, not wanting to put the show through more scheduling conflicts, declined to sign on for Season 9 so Chalke returned full time. In the series revival, Goranson once again played Becky. In Season 10, Goranson, as Becky, and Chalke, as a character named Andrea, meet and comment on how much they resemble one another. The Andrea character hires Becky to be her surrogate; this arrangement fails due to Becky's age (she is 43) making it unlikely she can conceive. In Season 1 of The Conners, which deals with life after Roseanne's death from an accidental opiate overdose, Becky, who never expected to get pregnant, announces she is expecting. The child's father, Becky's restaurant coworker Emilio, is an undocumented immigrant from Mexico and unable to help out financially, as he is a small-wage earner. With her family's support, Becky proceeds with the pregnancy. Becky likes but does not love Emilio, though she later warms to him and accepts his being part of her and her child's lives; Dan hires him as a drywall worker at his construction business, and Jackie tutors him in English.
American kestrels are sexually mature by their first spring. In migratory populations, the males arrive at the breeding ground before females, then the female selects a mate. Pair bonds are strong, often permanent. Pairs usually use previous nesting sites in consecutive years. This gives birds an advantage over younger or invading individuals, as they would already be familiar with the hunting grounds, neighbors, predators, and other features of the site. Males perform elaborate dive displays to advertise their territory and attract a mate. These displays consist of several climbs and dives, with three or four "klee" calls at their peaks. Females are promiscuous for about one to two weeks after their arrival at the nesting site. This is thought to stimulate ovulation. Food transfers from the male to the female occur from about four to five weeks prior to egg laying to one to two weeks after. American kestrels are cavity nesters, but they are able to adapt to a wide variety of nesting situations. They generally prefer natural cavities (such as in trees) with closed tops and tight-fitting entrances that provide for maximum protection of the eggs and young. Kestrels occasionally nest in holes created by large woodpeckers, or use the abandoned nests of other birds, such as red-tailed hawks, merlins, and crows. They have been recorded nesting on cliff ledges and building tops, as well as in abandoned cavities in cactuses. American kestrels also commonly utilize nesting boxes. Three to seven eggs (typically four or five) are laid approximately 24–72 hours apart.
=== Video games === Half-Life (1998) Half-Life 2 (2004) Half-Life 2: Episode One (2006) Half-Life 2: Episode Two (2007) Portal (2007) Counter-Strike: Global Offensive (additional music, 2015) Vanishing Realms: Rite of Steel (2016-2019)
2 HO–CH2CH2–Cl + Ca(OH)2 → 2 (CH2CH2)O + CaCl2 + 2H2O The produced ethylene oxide is purified by distillation. The chlorohydrin process allows to reach 95% conversion of ethylene chlorohydrin. The yield of ethylene oxide is about 80% of the theoretical value; for 1 tonne (0.98 long tons; 1.1 short tons) of ethylene oxide, about 200 kg (440 lb) of ethylene dichloride is produced. But, the major drawbacks of this process are high chlorine consumption and effluent load. This process is now obsolete.
His career has spanned the academic world and the BBC, while his books include Kissing Cousins (a comparative study of British and American social attitudes); critical portraits of the Amadeus Quartet and of Plácido Domingo; a study of the cultural impact of The Hitler Émigrés; an anthology of essays about today's leading historians; The Gilded Stage: A Social History of Opera and Just Passing Through – Interactions with the World 1938 – 2021; born in London, his parents coming from Anglo-Jewish families with roots in 19th-century Eastern Europe. Flora Solomon, (née Benenson; 28 September 1895 – 18 July 1984) was an influential Zionist. The first woman hired to improve working conditions at Marks & Spencer in London, Solomon was later instrumental in the exposure of the spy Kim Philby. She was the mother of Peter Benenson, founder of Amnesty International and founder of Blackmore Press, a British printing house. Her life was described in her autobiography A Woman's Way, written in collaboration with Barnet Litvinoff and published in 1984 by Simon & Schuster. The work was also titled Baku to Baker Street: The Memoirs of Flora Solomon.
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.
It is a seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, produced by chemical synthesis rather than extracted from biological tissue. Its design is based on tuftsin, a natural immunomodulatory tetrapeptide. The C-terminal Pro-Gly-Pro segment is a common stabilising motif in short regulatory peptides.