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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.
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.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
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.
| 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 |
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.
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.
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.
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.
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.
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.
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.
== Labeling methods == Proteins can be biotinylated chemically or enzymatically. Chemical biotinylation utilises various conjugation chemistries to yield nonspecific biotinylation of amines, carboxylates, sulfhydryls and carbohydrates (e.g., NHS-coupling gives biotinylation of any primary amines in the protein). Enzymatic biotinylation results in biotinylation of a specific lysine within a certain sequence by a bacterial biotin ligase. Most chemical biotinylation reagents consist of a reactive group attached via a linker to the valeric acid side chain of biotin. As the biotin binding pocket in avidin / streptavidin is buried beneath the protein surface, biotinylation reagents possessing a longer linker are desirable, as they enable the biotin molecule, once it has been attached to its target, to be more accessible to binding avidin/streptavidin/Neutravidin protein. This linker can also mediate the solubility of biotinylation reagents; linkers that incorporate poly(ethylene) glycol (PEG) can make water-insoluble reagents soluble or increase the solubility of biotinylation reagents that are already soluble to some extent.
A DNA helix usually does not interact with other segments of DNA, and in human cells, the different chromosomes even occupy separate areas in the nucleus called "chromosome territories". This physical separation of different chromosomes is important for the ability of DNA to function as a stable repository for information, as one of the few times chromosomes interact is in chromosomal crossover which occurs during sexual reproduction, when genetic recombination occurs. Chromosomal crossover is when two DNA helices break, swap a section and then rejoin. Recombination allows chromosomes to exchange genetic information and produces new combinations of genes, which increases the efficiency of natural selection and can be important in the rapid evolution of new proteins. Genetic recombination can also be involved in DNA repair, particularly in the cell's response to double-strand breaks. The most common form of chromosomal crossover is homologous recombination, where the two chromosomes involved share very similar sequences. Non-homologous recombination can be damaging to cells, as it can produce chromosomal translocations and genetic abnormalities. The recombination reaction is catalyzed by enzymes known as recombinases, such as RAD51. The first step in recombination is a double-stranded break caused by either an endonuclease or damage to the DNA.
=== Familia Neo/323C/323 Neo === The Familia Neo started production for the Japanese domestic market in 1994 (axed in 1996), and was also sold as the 323C in Europe and the 323 in Canada. Ford released a rebadged version which was mechanically the same although different bumpers, headlights and bonnet were fitted, badged as the Ford Laser Lynx in Japan and Australia, and the Ford Aztec in Taiwan. This model was only available as the Ford Laser Lynx in the Australian market, as Mazda already had the 323 Astina Hatch filling the gap for a hatchback in the Mazda range. To contradict this, Mazda Australia also offered two 323 saloons, the Astina/Lantis hardtop and the 323 Protegé until production of both models ceased in 1998. It featured a rear hatch with a divided glass, much like the Honda CR-X. Aesthetically the Familia Neo was very close in looks to a Mazda Lantis/323F and equated to a three-door version and also shared the Lantis suspension. The top specced Familia Neo was fitted with a DOHC 1839 cc BP-ZE engine which produced around 114–135 PS (84–99 kW) (depending on the market), and this was the same engine fitted to the base model Mazda Lantis. It was also sold for a single year (1995) in Canada as 323 GS. In Europe it was named Mazda 323C (for coupé), available for sale until September 1998 and it was equipped with 1.3 L SOHC, 1.5 L DOHC 16V, and 1.8 L DOHC 16V engine.
Also known as mediastinal emphysema to divers, pneumomediastinum is a volume of gas inside the mediastinum, the central cavity in the chest between the lungs and surrounding the heart and central blood vessels, usually formed by gas escaping from the lungs as a result of lung rupture. Gas bubbles escaping from a ruptured lung can travel along the outside of bronchioles and blood vessels until they reach the mediastinal cavity round the heart, major blood vessels, oesophagus and trachea. Gas trapped in the mediastinum expands as the diver continues to rise. The pressure of the trapped gas may cause intense pain inside the rib cage and in the shoulders, and the gas may compress the respiratory passageways, making breathing difficult, and collapse blood vessels. Symptoms range from pain under the sternum, shock, shallow breathing, unconsciousness, respiratory failure, and associated cyanosis. The gas will usually be absorbed by the body over time, and when the symptoms are mild, no treatment may be necessary. Otherwise it may be vented through a hypodermic needle inserted into the mediastinum. Recompression is not usually indicated.
Sources: en.wikipedia.org
=== U.S. federal government actions === In 2002, a panel of toxicologists, including several from EPA, proposed a level of 150 ppb for drinking water in the PFOA contaminated area around DuPont's Washington Works plant. This initially proposed level was much higher than any known environmental concentration and was over 2,000 times the level EPA eventually settled on for the drinking water health advisory. In July 2004, EPA filed a suit against DuPont alleging "widespread contamination" of PFOA near the Parkersburg, West Virginia plant "at levels exceeding the company's community exposure guidelines"; the suit also alleged that "DuPont had—over a 20 year period—repeatedly failed to submit information on adverse effects (in particular, information on liver enzyme alterations and birth defects in offspring of female Parkersburg workers)." In October 2005, a USFDA study was published revealing PFOA and PFOA precursor chemicals in food contact and PTFE products. On January 25, 2006, EPA announced a voluntary program with several chemical companies to reduce PFOA and PFOA precursor emissions by the year 2015. On February 15, 2005, EPA's Science Advisory Board (SAB) voted to recommended that PFOA should be considered a "likely human carcinogen". On May 26, 2006, EPA's SAB addressed a letter to Administrator Stephen L. Johnson. Three-quarters of advisers thought the stronger "likely to be carcinogenic" descriptor was warranted, in opposition to EPA's own PFOA hazard descriptor of "suggestive evidence of carcinogenicity, but not sufficient to assess human carcinogenic potential".
=== Higher education === During his 2022 gubernatorial campaign, Moore called a plan to cancel up to $20,000 in federal student loan debt a "good first step" and said he would push the Biden administration to forgive more federal student debt if elected governor. In June 2023, Moore opposed the U.S. Supreme Court's ruling in Students for Fair Admissions v. Harvard, which held that race-based affirmative action in college admissions violated the Equal Protection Clause, calling it a "misguided ruling". In April 2024, Moore signed into law a bill banning legacy admissions at Maryland colleges and universities.
Seven people, including Pitt police officers, were injured and two, including the shooter, were killed during the incident. Shick was reported to have a history of mental illness and had behaved erratically in the weeks before the shooting. Handwritten messages complaining about his medical treatment and the evils of "corporate America," floor plans and blueprints of Thomas Detre Hall, and supplies for making Molotov cocktails were found in his apartment after the shooting.
Sources: en.wikipedia.org
=== Medical use === The appeal of conotoxins for creating pharmaceutical drugs is the precision and speed with which the chemicals act; many of the compounds target only a particular class of receptor. This means that they can reliably and quickly produce a particular effect on the body's systems without side effects; for example, almost instantly reducing heart rate or turning off the signaling of a single class of nerve, such as pain receptors. Ziconotide, a powerful atypical painkiller, was initially isolated from the venom of the magician cone snail, Conus magus. It was approved by the U.S. Food and Drug Administration in December 2004 under the name Prialt. Other drugs based on cone snail venom targeting Alzheimer's disease, Parkinson's disease, depression, and epilepsy are in clinical or preclinical trials. Many peptides produced by the cone snails show prospects for being potent pharmaceuticals, such as AVC1, isolated from the Australian species, the Queen Victoria cone, Conus victoriae, and have been highly effective in treating postsurgical and neuropathic pain, even accelerating recovery from nerve injury. Geography and tulip cone snails, as well as the Conus kinoshitai, are known to secrete a type of insulin that paralyzes nearby fish by causing hypoglycaemic shock. They are the only two non-human animal species known to use insulin as a weapon. Cone snail insulin is capable of binding to human insulin receptors and researchers are studying its use as a potent fast-acting therapeutic insulin.
==== Medicaid restrictions and funding cuts ==== The law cuts over $1.2 trillion in federal spending, primarily from the low-income health insurance program Medicaid and the nutrition funding program SNAP. The law:
==== US Federal Trade Commission ==== On 27 February 2019, the United States Federal Trade Commission (FTC) reached a consent decree with ByteDance, fining it US$5.7 million for collecting information from minors under the age of 13 in violation of the Children's Online Privacy Protection Act (COPPA). ByteDance responded by adding a kids-only mode to TikTok which blocks the upload of videos, the building of user profiles, direct messaging, and commenting on others' videos, while still allowing the viewing and recording of content. In May 2020, an advocacy group filed a complaint with the FTC saying that TikTok had violated the terms of the February 2019 consent decree with the FTC, which sparked subsequent congressional calls for a renewed FTC investigation. In March 2022, following a class action lawsuit for violations of COPPA, TikTok settled for US$1.1 million. In March 2024, it was reported that the FTC continues to investigate TikTok. In August 2024, the FTC and US Department of Justice filed a joint lawsuit alleging violations of the 2019 consent decree. In August 2026, TikTok and ByteDance agreed to pay $400 million to settle the lawsuit.
2 Er(s) + 3 F2(g) → 2 ErF3(s) [pink] 2 Er(s) + 3 Cl2(g) → 2 ErCl3(s) [violet] 2 Er(s) + 3 Br2(g) → 2 ErBr3(s) [violet] 2 Er(s) + 3 I2(g) → 2 ErI3(s) [violet] Erbium dissolves readily in dilute sulfuric acid to form solutions containing hydrated Er(III) ions, which exist as rose red [Er(H2O)9]3+ hydration complexes:
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.
Selank is a synthetic seven-amino-acid peptide modeled on tuftsin, a fragment of the immunoglobulin G heavy chain. It was designed in Russia to combine anxiolytic and immunomodulatory properties in one molecule.