Everything below concerns GABA-A receptor. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-09-28. Where a claim depends on a specific study, the study is described rather than over-claimed.
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 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.
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
| 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 |
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.
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.
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.
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.
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.
As a salt, its dominant use is as an emulsifier for the emulsion polymerization of fluoropolymers such as PTFE, polyvinylidene fluoride, and fluoroelastomers. For this use, 3M subsidiary Dyneon has a replacement emulsifer despite DuPont stating PFOA is an "essential processing aid". In the past PFOA was used in the production of Gore-Tex as it is PTFE-based. In PTFE processing, PFOA is in aqueous solution and forms micelles that contain tetrafluoroethylene and the growing polymer. PFOA can be used to stabilize fluoropolymer and fluoroelastomer suspensions before further industrial processing and in ion-pair reversed-phase liquid chromatography it can act as an extraction agent. PFOA also finds uses in electronic products and as an industrial fluorosurfactant. In a 2009 EPA study of 116 products, purchased between March 2007 and May 2008 and found to contain at least 0.01% fluorine by weight, the concentrations of PFOA were determined. Concentrations shown below range from not detected, or ND, (with the detection limit in parentheses) to 6750 with concentrations in nanograms of PFOA per gram of sample (parts per billion) unless stated otherwise.
Briefly, the steps in beta oxidation are as follows: Dehydrogenation by acyl-CoA dehydrogenase, yielding 1 FADH2 Hydration by enoyl-CoA hydratase Dehydrogenation by 3-hydroxyacyl-CoA dehydrogenase, yielding 1 NADH + H+ Cleavage by thiolase, yielding 1 acetyl-CoA and a fatty acid that has now been shortened by 2 carbons (forming a new, shortened acyl-CoA) This beta oxidation reaction is repeated until the fatty acid has been completely reduced to acetyl-CoA or, in the case of fatty acids with odd numbers of carbon atoms, acetyl-CoA and 1 molecule of propionyl-CoA per molecule of fatty acid. Each beta oxidative cut of the acyl-CoA molecule eventually yields 5 ATP molecules in oxidative phosphorylation. The acetyl-CoA produced by beta oxidation enters the citric acid cycle in the mitochondrion by combining with oxaloacetate to form citrate. Coupled to oxidative phosphorylation this results in the complete combustion of the acetyl-CoA to CO2 and water. The energy released in this process is captured in the form of 1 GTP and 11 ATP molecules per acetyl-CoA molecule oxidized. This is the fate of acetyl-CoA wherever beta oxidation of fatty acids occurs, except under certain circumstances in the liver.
Etanidazole is a nitroimidazole drug that was investigated in clinical trials for its radiosensitizing properties in cancer treatment. Administration of etanidazole results in a decrease of glutathione concentration and inhibits glutathione S-transferase. The result is that tissues become more sensitive to the ionizing radiation.
R−H + M+ = R−M + H+. Similar to anion resins, in cation resins the regeneration involves the use of a strongly acidic solution, e.g. aqueous hydrochloric acid. During regeneration, the regenerant chemical passes through the resin and flushes out the trapped positive ions, renewing the resin exchange capacity.
=== Life Expectancy After Starting Kidney Dialysis === Life expectancy after starting kidney dialysis for end-stage kidney disease (ESKD) varies significantly based on factors such as age, comorbidities, dialysis modality, and access to healthcare. Dialysis extends life compared to untreated ESKD but does not restore normal kidney function. Median survival is approximately 3–5 years, with 5-year survival rates around 35–42% for hemodialysis (HD) patients. Mortality is highest in the first year (15–20%), primarily from cardiovascular events or infections.
Sources: en.wikipedia.org
At the advent of this conference, several armed groups were immediately organized and began operating in Central Luzon. A significant event was on March 13, 1942, when a squadron headed by Felipa Culala (alias Dayang-Dayang) encountered and defeated Japanese forces in Mandili, Candaba, Pampanga. News of Culala's successful raid raised morale for the resistance fighters. On March 29, 1942, peasant leaders met in a forest clearing located in Sitio Bawit, Barrio San Julian, at the junction of Tarlac, Pampanga, and Nueva Ecija to form a united organization. Hukbong Bayan Laban sa mga Hapon was chosen as the name of the organization. After the meeting, a military committee was formed with Taruc (Supremo), Castro Alejandrino (Vice Commander), Bernardo Poblete (Tandang Banal), and Culala as members. The Hukbalahap high command was also joined by the military commissariat; a party apparatus that provided guidance to the Huks. The CLB was regarded as the "wartime version of the PKP". While PKP officials did assume important positions in the Huk structure, the movement encompassed more that simply members of the PKP and its affiliated organizations. Robert Lapham reports either Luis Taruc or Casto Alejandrino met with Lieutenant Colonel Claude Thorp at Camp Sanchez in the spring of 1942, and the conferees agreed to cooperate, share equipment and supplies, with the Americans providing trainers.
Chemical elements data references List of chemical elements – atomic mass, atomic number, symbol, name List of minerals – Minerals Electron configurations of the elements (data page) – electron configuration, electrons per shell Densities of the elements (data page) – density (solid, liquid, gas) Electron affinity (data page) – electron affinity Melting points of the elements (data page) – melting point Boiling points of the elements (data page) – boiling point Critical points of the elements (data page) – critical point Heats of fusion of the elements (data page) – heat of fusion Heats of vaporization of the elements (data page) – heat of vaporization Heat capacities of the elements (data page) – heat capacity Vapor pressures of the elements (data page) – vapor pressure Electronegativities of the elements (data page) – electronegativity (Pauling scale) Ionization energies of the elements (data page) – ionization energies (in eV) and molar ionization energies (in kJ/mol) Atomic radii of the elements (data page) – atomic radius (empirical), atomic radius (calculated), van der Waals radius, covalent radius Electrical resistivities of the elements (data page) – electrical resistivity Thermal conductivities of the elements (data page) – thermal conductivity Thermal expansion coefficients of the elements (data page) – thermal expansion Speeds of sound of the elements (data page) – speed of sound Elastic properties of the elements (data page) – Young's modulus, Poisson ratio, bulk modulus, shear modulus Hardnesses of the elements (data page) – Mohs hardness, Vickers hardness, Brinell hardness Abundances of the elements (data page) – Earth's crust, sea water, Sun and solar system List of oxidation states of the elements – oxidation states List of compounds List of CAS numbers by chemical compound List of Extremely Hazardous Substances List of inorganic compounds List of organic compounds List of alkanes List of alloys Other List of thermal conductivities List of purification methods in chemistry List of unsolved problems in chemistry
As per the Taliban officials, 55 Pakistani soldiers were killed, and several others were captured. Taliban-led Afghanistan's officials further added that one military headquarters and 19 border outposts had been captured, while 4 border outposts were destroyed during the operation. Zabihullah Mujahid named seven of the border outposts that Taliban officials claimed to have captured. According to reports, the outposts were located inside Afghanistan, and it remained unclear how border outposts belonging to Pakistani forces were located on Afghan soil. At midnight local time (19:30 GMT), the Taliban-led Afghan Ministry of Defense announced the end of its four-hour operation. Pakistani officials rejected Taliban claims and stated that military action against Taliban forces was continuing. They further added that the attack had been repulsed, that the Taliban had suffered heavy losses, and that two Pakistani soldiers had been killed and three others were injured during the four-hour engagement. In response to the Taliban's operation, Pakistan carried out air and ground strikes against Afghan Taliban positions in Kabul, Kandahar, Paktia, and Nangarhar. Faisal Karim Kundi, governor of Khyber Pakhtunkhwa, stated that the Afghan Taliban started the war and Pakistan will be the one to end it, while Khawaja Asif, Pakistan's defence minister, announced the start of an "open war" between the two countries. Pakistani officials stated that around 133 Taliban fighters were killed and more than 200 were injured during the clashes and subsequent operation.
== History == The approach was promulgated as an alternative medicine concept by Andrew Taylor Still, inventor of osteopathy, and his early students. The exact phrase "myofascial release" was coined in the 1960s by Robert Ward, an osteopath who studied with Ida Rolf, the originator of Rolfing. Ward, along with physical therapist John Barnes, are considered the two primary founders of Myofascial Release. Ward also suggests, in other sources, that the term "myofascial release" was coined in 1981, when it was used as the name of a course taught at Michigan State University. It was popularized and taught to therapists, massage therapists and occupational therapists by John F. Barnes through his seminars.
== Nomenclature and structure == The terms polyaromatic hydrocarbon, or polynuclear aromatic hydrocarbon (abbreviated as PNA) are also used for this concept. By definition, polycyclic aromatic hydrocarbons have multiple aromatic rings, precluding benzene from being considered a PAH. Sources such as the US EPA and CDC consider naphthalene to be the simplest PAH. Most authors exclude compounds that include heteroatoms in the rings, or carry substituents. A polyaromatic hydrocarbon may have rings of various sizes, including some that are not aromatic. Those that have only six-membered rings are said to be alternant. The following sets of examples illustrate several of the types of variations that are possible.
Sources: en.wikipedia.org
On 21 July, the Syrian Observatory for Human Rights said that nine civilians were injured by a drone attack on the city of Shahba by Bedouin tribes. On 25 July, the Syrian Observatory for Human Rights reported ceasefire violations in Umm al-Zaytoun village and areas of Reema Hazem and in Walgha. Tensions persisted in the Kanaker region with the presence of tribal gunmen. On 26 July, the spiritual leadership of the Druze, headed by Sheikh Hikmat al-Hijri, announced the formation of a "Supreme Legal Committee" consisting of six judges, including four judicial advisors, and three lawyers. The committee outlined its responsibilities as managing public affairs across all sectors in Suwayda, including administrative, security, and service-related matters.
Logical Observation Identifiers Names and Codes (LOINC) is a database and universal standard for identifying medical laboratory observations. First developed in 1994, it was created and is maintained by the Regenstrief Institute, a US nonprofit medical research organization. LOINC was created in response to the demand for an electronic clinical care and management database and is publicly available at no cost. It is endorsed by the American Clinical Laboratory Association. Since its inception, the database has expanded to include not just medical laboratory code names but also nursing diagnosis, nursing interventions, outcomes classification, and patient care data sets.
Many proteins produced within the cell are secreted outside the cell to function as extracellular proteins. Extracellular proteins are exposed to a wide variety of conditions. To stabilize the 3D protein structure, covalent bonds are formed either within the protein or between the different polypeptide chains in the quaternary structure. The most prevalent type is a disulfide bond (also known as a disulfide bridge). A disulfide bond is formed between two cysteine amino acids using their side chain chemical groups containing a Sulphur atom, these chemical groups are known as thiol functional groups. Disulfide bonds act to stabilize the pre-existing structure of the protein. Disulfide bonds are formed in an oxidation reaction between two thiol groups and therefore, need an oxidizing environment to react. As a result, disulfide bonds are typically formed in the oxidizing environment of the endoplasmic reticulum catalyzed by enzymes called protein disulfide isomerases. Disulfide bonds are rarely formed in the cytoplasm as it is a reducing environment.
In tissue engineering, a highly porous artificial extracellular matrix is needed to support and guide cell growth and tissue regeneration. Natural and synthetic biodegradable polymers have been used to create such scaffolds. Simon, in a 1988 NIH SBIR grant report, showed that electrospinning could be used to produce nano- and submicron-scale polystyrene and polycarbonate fibrous mats specifically intended for use as in vitro cell substrates. This early use of electrospun fibrous lattices for cell culture and tissue engineering showed that Human Foreskin Fibroblasts (HFF), transformed Human Carcinoma (HEp-2), and Mink Lung Epithelium (MLE) would adhere to and proliferate upon the fibers. Nanofiber scaffolds are used in bone tissue engineering to mimic the natural extracellular matrix of the bones. The bone tissue is arranged either in a compact or trabecular pattern and composed of organized structures that vary in length from the centimeter range all the way to the nanometer scale. Nonmineralized organic component (i.e. type 1 collagen), mineralized inorganic component (i.e. hydroxyapatite), and many other noncollagenous matrix proteins (i.e. glycoproteins and proteoglycans) make up the nanocomposite structure of the bone ECM. The organic collagen fibers and the inorganic mineral salts provide flexibility and toughness, respectively, to ECM. Although the bone is a dynamic tissue that can self-heal upon minor injuries, it cannot regenerate after experiencing large defects such as bone tumor resections and severe nonunion fractures because it lacks the appropriate template.
=== Collagen-like characteristics === Spongin and collagen exhibit comparable filament structure, both displaying a hierarchical organization of nanofibrils, microfibrils, and fibers, as well as a triple-helical based structure. Spongin microfibrilis measure approximately 10 nm in diameter and exhibit a periodic banding pattern every 60 nm, comparing to collagen's 67 nm periodicity. Despite the structural similarities, amino acid analysis reveals that spongin contains significantly higher levels of tyrosine residues, approximately 90% of which are mono- or di-brominated derivatives. This abundance of tyrosine is related to the oxidation of phenylalanine residues, which are prevalent in collagen but nearly absent in spongin. The brominated tyrosine derivatives are hypothesized to play a crucial role in stabilizing spongin's triple-helical structure through cross-linking.
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.
Reports describe effects on GABA-A receptor expression, monoamine turnover, and neurotrophic factor levels. These are proposed mechanisms drawn mainly from animal models. No single molecular target has been established.