The short version of Regulatory peptide fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-11-23 and is reviewed periodically as new material appears.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analog of the tetrapeptide tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Reported consistently across pharmacopoeial descriptions |
| Appearance | White to off-white lyophilized powder | Typical form of research-grade material |
| Solubility | Freely soluble in water | Aqueous buffers; poor in nonpolar solvents |
| Typical storage temperature | -20 degrees Celsius | Lyophilized powder; protect from moisture |
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.
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.
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.
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.
Autocrine signaling is a form of signaling in which a cell secretes a hormone or chemical messenger (called the autocrine agent) that binds to autocrine receptors on the same cell, leading to changes in the cells.
Nevertheless, phosphatidylinositol-3,4,5-trisphosphate 3-phosphatase, the well-studied tumor suppressor that is better known as PTEN, gets its name from homology with PTPs and tensin 1. More detailed structure comparisons have revealed that tensins 1-3, PTEN, auxilin and other proteins in animals, plants and fungi comprise a PTP-C2 superdomain. An integrated PTP domain and C2 domain, the PTP-C2 superdomain came into existence over 1 billion years ago and has functioned as a single heritable unit since then. The first tensin cDNA sequence was isolated from chicken. Analysis of knockout mice has demonstrated critical roles of tensin in renal function, muscle regeneration, and cell migration. Evidence is now emerging to suggest tensin is an important component linking the ECM, the actin cytoskeleton, and signal transduction. Therefore, tensin and its downstream signaling molecules may be targets for therapeutic interventions in renal disease, wound healing and cancer.
The step of salting the raw materials as well as the addition of red pepper powder inhibits the pathogenic and putrefactive bacteria present in the microflora, allowing the lactic acid bacteria (LAB) to flourish and become the dominant microorganism. These anaerobic microorganisms steadily increase in number during the middle stages of fermentation, and prefer to be kept at low temperatures of about 10 °C, pH of 4.2-4, and remain in the presence of 1.5% – 4% NaCl. A faster fermentation at a higher temperature may be chosen as well to accelerate the growth of bacterial cultures for a faster decrease in pH level. Since the raw cruciferous vegetables themselves are the source of LAB required for fermentation, no starter culture is required for the production of kimchi; rather, spontaneous fermentation occurs. The total population of microorganisms present at the beginning of processing determines the outcome of fermentation, causing the final product to be highly variable in terms of quality and flavor. Currently, there are no recommended approaches to control the microbial community during fermentation to predict the outcome. In the industrial production of kimchi, starter cultures made up of Leu. mesenteroides, Leu. citreum, and Lb. plantarum are used, which are often unsuccessful because they fail to outcompete the naturally occurring cultures on the raw materials.
The initial symptoms were similar to other viral diseases that are still extant, such as influenza and the common cold: fever of at least 38.3 °C (101 °F), muscle pain, malaise, headache and fatigue. As the digestive tract was commonly involved, nausea, vomiting, and backache often occurred. The early prodromal stage usually lasted 2–4 days. By days 12–15, the first visible lesions – small reddish spots called enanthem – appeared on mucous membranes of the mouth, tongue, palate, and throat, and the temperature fell to near-normal. These lesions rapidly enlarged and ruptured, releasing large amounts of virus into the saliva. Variola virus tended to attack skin cells, causing the characteristic pimples, or macules, associated with the disease. A rash developed on the skin 24 to 48 hours after lesions on the mucous membranes appeared. Typically the macules first appeared on the forehead, then rapidly spread to the whole face, proximal portions of extremities, the trunk, and lastly to distal portions of extremities. The process took no more than 24 to 36 hours, after which no new lesions appeared. At this point, variola major disease could take several very different courses, which resulted in four types of smallpox disease based on the Rao classification: ordinary, modified, malignant (or flat), and hemorrhagic smallpox. Historically, ordinary smallpox had an overall fatality rate of about 30%, and the malignant and hemorrhagic forms were usually fatal. The modified form was almost never fatal.
Rhodiola rosea (commonly golden root, rose root, roseroot, Aaron's rod, Arctic root, king's crown, lignum rhodium, orpin rose) is a perennial flowering plant in the family Crassulaceae. It grows naturally in wild Arctic regions of Europe (including Britain), Asia, and North America (New Brunswick, Newfoundland and Labrador, Nova Scotia, Quebec; Alaska, Maine, New York, North Carolina, Pennsylvania, Vermont), and can be propagated as a groundcover. Although Rhodiola rosea has been used in traditional medicine, there is no high-quality clinical evidence of its effectiveness to treat any disease. The United States Food and Drug Administration has issued several warnings to manufacturers of R. rosea based dietary supplements for making false health claims about safety and efficacy. The plant is threatened in many countries due to rapidly growing demand. R. rosea has been identified by various farmers and researchers as a potential cash crop naturally suited for cultivation in Arctic climates. Supply comes mostly from wild harvesting on an industrial scale, and a combination of growing scarcity and a lack of regulation has led to environmental degradation, substitution or adulteration in the market, and illegal harvesting in protected areas.
Sources: en.wikipedia.org
=== PG === The hydrostatic pressure within the glomerular capillaries is determined by the pressure difference between the fluid entering immediately from the afferent arteriole and leaving through the efferent arteriole. The pressure difference is approximated by the product of the total resistance of the respective arteriole and the flux of blood through it:
BASF announced that the transaction would allow the company to focus on its chemical and refinery catalysts business. Since 2016, BASF has partnered with a subsidiary of Xinjiang Zhongtai Group, a company sanctioned under the Uyghur Forced Labor Prevention Act, to operate a plant in Korla. In October 2017, BASF announced it would buy seed and herbicide businesses from Bayer for €5.9 billion ($7 billion), as part of Bayer's acquisition of Monsanto. The company announced the start of a US$10 billion investment project in the south-western Chinese city of Zhanjiang, in November 2019. The project was approved in 2022. This ″Verbund″ site is intended for the production of engineering plastics and TPU. The site would be the third-largest BASF site worldwide, following Ludwigshafen, Germany, and Antwerp, Belgium. The first plant started up in 2022, and the entire site is expected to be completed by 2030.
Phrixotoxins are peptide toxins derived from the venom of the Chilean copper tarantula Phrixotrichus auratus, also named Paraphysa scrofa. Phrixotoxin-1 and -2 block A-type voltage-gated potassium channels; phrixotoxin-3 blocks voltage-gated sodium channels. Similar toxins are found in other species, for instance the Chilean rose tarantula.
== Sources == Tityus serrulatus, also known as the Brazilian yellow scorpion, is from the genus Tityus belonging to the family Buthidae. TsPep2 is identified from the venom of Tityus serrulatus by using a cDNA primer sequence based on the C-terminal amino acid sequence of KTx2 from Androctonus australis.
== Lateral and mid support structures == The midsection of the vagina is supported by its lateral attachments to the arcus tendineus. Some describe the pubocervical fascia as extending from the pubic symphysis to the anterior vaginal wall and cervix. Anatomists do not agree on its existence.
Sources: en.wikipedia.org
== Overdose == MDMA overdose symptoms vary widely due to the involvement of multiple organ systems. Some of the more overt overdose symptoms are listed in the table below. The number of instances of fatal MDMA intoxication is low relative to its usage rates. In most fatalities, MDMA was not the only drug involved. Acute toxicity is mainly caused by serotonin syndrome and sympathomimetic effects. MDMA's toxicity in overdose may be exacerbated by caffeine, with which it is frequently cut in order to increase volume. The estimated fatal dose of MDMA in humans is around 15 or 16 times a typical recreational dose. Sympathomimetic side effects can be managed with carvedilol. A scheme for management of acute MDMA toxicity has been published focusing on treatment of hyperthermia, hyponatraemia, serotonin syndrome, and multiple organ failure.
Furthermore, the optimisation of the conditions for the protease in temperature and pH allows for the completion of the digestion of a sample in 30 min. Surfactant (detergents) can aid in the solubilization and denaturing of proteins in the gel and thereby shorten digestion times and increase protein cleavage and the number and amount of extracted peptides, especially for lipophilic proteins such as membrane proteins. Cleavable detergents are detergents that are cleaved after digestion, often under acidic conditions. This makes the addition of detergents compatible with mass spectrometry.
Guidelines have been set up by various governing bodies regarding the standards that are followed by practicing forensic scientists. For forensic chemists, the international Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) presents recommendations for the quality assurance and quality control of tested materials. In the identification of unknown samples, protocols have been grouped into three categories based on the probability for false positives. Instruments and protocols in category A are considered the best for uniquely identifying an unknown material, followed by categories B and then C. To ensure the accuracy of identifications SWGDRUG recommends that multiple tests using different instruments be performed on each sample, and that one category A technique and at least one other technique be used. If a category A technique is not available, or the forensic chemist decides not to use one, SWGDRUG recommends that at least three techniques be used, two of which must be from category B. Combination instruments, such as GC-MS, are considered two separate tests as long as the results are compared to known values individually For example, the GC elution times would be compared to known values along with the MS spectra. If both of those match a known substance, no further tests are needed. Standards and controls are necessary in the quality control of the various instruments used to test samples. Due to the nature of their work in the legal system, chemists must ensure that their instruments are working accurately.
An yttrium–barium cuprate, YBa2Cu3O7−x (or Y123), was the first superconductor found above liquid nitrogen boiling point. The three different metals in the YBa2Cu3O7 superconductor are in the mole ratio of 1 to 2 to 3 for yttrium to barium to copper, respectively; hence, this particular superconductor has often been referred to as the 123 superconductor. The unit cell of YBa2Cu3O7 consists of three perovskite unit cells, which is pseudocubic, nearly orthorhombic. The other superconducting cuprates have another structure: they have a tetragonal cell. Each perovskite cell contains a Y or Ba atom at the center: Ba in the bottom unit cell, Y in the middle one, and Ba in the top unit cell. Thus, Y and Ba are stacked in the sequence [Ba–Y–Ba] along the c-axis. All corner sites of the unit cell are occupied by Cu, which has two different coordinations, Cu(1) and Cu(2), with respect to oxygen. There are four possible crystallographic sites for oxygen: O(1), O(2), O(3) and O(4). The coordination polyhedra of Y and Ba with respect to oxygen are different. The tripling of the perovskite unit cell leads to nine oxygen atoms, whereas YBa2Cu3O7 has seven oxygen atoms and, therefore, is referred to as an oxygen-deficient perovskite structure. The structure has a stacking of different layers: (CuO)(BaO)(CuO2)(Y)(CuO2)(BaO)(CuO). One of the key feature of the unit cell of YBa2Cu3O7−x (YBCO) is the presence of two layers of CuO2. The role of the Y plane is to serve as a spacer between two CuO2 planes. In YBCO, the Cu–O chains are known to play an important role for superconductivity.
Sources: en.wikipedia.org
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.
The first four residues of Selank reproduce the tuftsin sequence Thr-Lys-Pro-Arg. A Pro-Gly-Pro extension at the C-terminus was added to slow enzymatic breakdown and extend residence time.
It holds marketing authorization in Russia, where nasal drop formulations are sold. No equivalent approval exists in the European Union, the United States, or most other countries.
Selank is a synthetic heptapeptide designed as a stabilized analog of the natural tetrapeptide tuftsin. It has been investigated mainly for anxiolytic and cognitive effects. It is not an approved pharmaceutical in most countries.