The short version of Enkephalinase fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-01-10 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue with a C-terminal Pro-Gly-Pro tail |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Abbreviated TKPRPGP in most catalogues |
| Molecular mass | About 752 Da | Value for the free peptide |
| Solubility | Freely soluble in water | Aqueous solutions are kept cold and used promptly |
| Typical storage | -20 °C, dry, protected from light | Applies to the lyophilised powder before reconstitution |
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.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
The research results (see table) indicate that about 1 in 5 people have a slow transit (type 1 and 2 stools), while 1 in 12 has an accelerated transit (type 5 and 6 stools). Moreover, the nature of the stool is affected by age, sex, body mass index, whether or not they had cholecystectomy and possible psychosomatic components (somatisation); there were no effects from factors such as smoking, alcohol, the level of education, a history of appendectomy or familiarity with gastrointestinal diseases, civil state, or the use of oral contraceptives.
Several studies have found that Acraspeda is paraphyletic, with Hydrozoa being more closely related to Scyphozoa than to the other classes. At the same time, other studies have recovered Acraspeda as being monophyletic. The subphylum Anthozoa is argued to have either two or three classes, but the relationships between them is not disputed; the tube-dwelling anemones of the class Ceriantharia have consistently shown to be more closely related to the Hexacorallia than to the Octocorallia.
Senate Majority Leader John Thune and U.S. Senate Republican Whip John Barrasso say that McConnell has spoken with them. July 8 2026 United States Senate elections: U.S. Senate Democratic Party nominee Graham Platner suspends his campaign in the upcoming U.S. Senate race in Maine amidst ongoing controversies surrounding his campaign, leaving the party to seek a replacement challenger to incumbent Republican Susan Collins. Iran war: The interim ceasefire between the United States and Iran breaks down after Iranian attacks on commercial vessels in the Strait of Hormuz. Trump declares the agreement "over", while saying that negotiations may continue. The U.S. Central Command says it struck around 90 Iranian military targets, including air defense, missile, drone and naval facilities. An additional U.S. strike hits a railway bridge in Golestan province on a trade route linking Iran with Russia and China. At the 2026 NATO summit in Ankara, Trump says that he has ordered Treasury Secretary Scott Bessent to halt all U.S. trade with Spain, calls Spain a "terrible partner" in NATO amid disputes over Spain's defense spending and the Iran War, and declares that the US will provide Ukraine a license to build Patriot missiles. July 9 Iran war: Trump says that Iran contacted him and they want to make an agreement. The U.S. Department of Justice announces that a federal grand jury has indicted eight men over an alleged plot to attack the UFC Freedom 250 event at the White House in Washington, D.C. last month.
Sources: en.wikipedia.org
=== General Information about the Museum === Timings: 10 am to 7 pm (Monday to Friday) Closed: Saturday, Sunday, and All Gazetted Holidays Entry: Free Photography: Allowed Videography: After prior permission of the Competent Authority
==== Hepatitis ==== In this pattern, hepatocellular necrosis is associated with infiltration of inflammatory cells. There can be three types of drug-induced hepatitis. (A) viral hepatitis is the most common, where histological features are similar to acute viral hepatitis. (B) in focal or non-specific hepatitis, scattered foci of cell necrosis may accompany lymphocytic infiltration. (C) chronic hepatitis is very similar to autoimmune hepatitis clinically, serologically, and histologically.
Cape Verde, Curaçao, Jordan, and Uzbekistan made their World Cup debuts. Qatar qualified for the tournament through qualification for the first time, as its only previous appearance was as host in 2022. DR Congo and Haiti returned to the tournament after appearing in their only previous tournament in 1974. Iraq returned to the tournament after appearing in its only previous tournament in 1986. Austria, Norway, and Scotland returned to the tournament after last appearing in 1998. Four-time champion Italy failed to qualify after losing the European playoff final to Bosnia and Herzegovina on penalties, becoming the first former champion to miss three consecutive World Cups; as in 2018 and 2022, Italy was the only former champion that did not qualify. With a FIFA Men's World Ranking of 12, Italy was also the highest-ranking team that did not qualify. The qualified teams, listed by region, with numbers in parentheses indicating final positions in the FIFA Men's World Ranking before the tournament were:
where ABCD+ is selected by MS1, dissociates into molecule AB and ion CD+. The ion is selected in the second mass spectrometry stage MS2 then undergoes further fragmentation to form ion D+ which is selected in the third mass spectrometry stage MS3 and detected. Multiple reaction monitoring (MRM) is the application of selected reaction monitoring to multiple product ions from one or more precursor ions, for example
Sources: en.wikipedia.org
== Causes == Colombia has a long history of political violence. Land, power, and wealth were unevenly distributed and many rural citizens were used to having to fend for themselves. There is no consensus about the date on which the conflict began, with some saying 1958 (with the start of the Frente Nacional (National Front)) and others 1964 (with the creation of the FARC). In the mid-1980s, Colombia granted local governments greater political and fiscal autonomy. This strengthened the government's position in more remote regions. In 1985, during peace talks with then-President Belisario Betancur, the FARC created the left-wing Patriotic Union party as a route from violence to mainstream politics. Between 1985 and 2002, 4,153 members and supporters of the party were kidnapped and murdered by right-wing paramilitaries with government support. This included two presidential candidates, 6 out of 16 congressmembers, 17 regional representatives, and 163 councilmembers. These killings aggravated the conflict. In the 1980s, drug trafficking increased, bringing a concomitant increase in violence. Trafficking began in the 1960s and 70s when a group of Americans began to smuggle marijuana. Later, the American Mafia moved into drug trafficking in Colombia alongside local marijuana producers. Cocaine and other drugs produced in Colombia were mostly consumed in the US, as well as Europe. Organized crime in Colombia grew increasingly powerful in the 1970s and 80s with the introduction of massive drug trafficking to the United States from Colombia.
The Center for Surveillance, Epidemiology and Laboratory Services (CSELS) was a branch of the US Centers for Disease Control and Prevention (CDC) from 2013-2022 that provided scientific service, expertise, skills, and tools in support of national efforts to promote health; prevent disease, injury and disability; and prepare for emerging health threats. It was founded in 2013 and had over 700 employees and contractors before its divisions and office of the director were reorganized. CSELS managed over 30 programs across four divisions: Division of Health Informatics and Surveillance, Division of Laboratory Systems, Division of Public Health Information Dissemination, and the Division of Scientific Education and Professional Development.
=== Diels-Alder reaction === Diels-Alder reaction between cyclopentadiene and chlorosulfonyl isocyanate (CSI) can be utilized to obtain both β- as well as γ-lactam. At lower temp (−78 °C), β-lactam is the preferred product. At optimum temperatures, a highly useful γ-lactam known as Vince Lactam is obtained.
== External links == SR-17018 - Isomer Design r/SR17018 - Reddit SR-17018 Guide: How to Take It and Some Simplified Science - Reddit SR-17018 Education and Discussion - Facebook Groups - Facebook SR-17018 Harm Reduction (sr17018.org) Save SR-17018 (stop-sr17-ban.com) SR-17018 - Wikipedia Pageviews Analysis
In addition, Brazil already managed a peacekeeping mission in Haiti ($350 million) and makes in-kind contributions to the World Food Programme ($300 million). The scale of this aid places it on par with China and India. The Brazilian South-South aid has been described as a "global model in waiting".
Sources: en.wikipedia.org
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.
Tuftsin is a natural tetrapeptide derived from the Fc portion of immunoglobulin G. Selank retains that tetrapeptide at its N-terminus and adds three residues to improve resistance to enzymatic breakdown. The relationship is structural, and the two molecules are not interchangeable in experimental work.
It holds a product registration in Russia for intranasal use as an anxiolytic. Registrations of that kind are not automatically accepted by regulators elsewhere. In most other countries it is treated as an unapproved substance or a research material.
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.