If you have been reading about Neurotrophic factor and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-11-24. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Route studied | Intranasal | Predominant route in published reports |
| Circulation stability | Short, minutes scale | Peptidases cleave it; the tail slows the process |
| Analytical method | RP-HPLC with mass spectrometry | Used for identity and purity assessment |
| Reported outcome domains | Anxiety and cognitive measures | Derived from small, mostly regional trials |
| Regulatory status | Marketed in Russia | Availability outside that market is limited |
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.
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.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
Regulatory treatment varies by jurisdiction. In Russia the compound is a registered prescription product, while in the European Union and the United States it is generally handled as a research chemical without a marketing authorization. Suppliers therefore operate outside pharmaceutical oversight, and buyers rely on supplier documentation for purity and identity claims. Chain of custody and third-party testing are the main verification tools. Analysts note that the absence of a pharmacopoeial monograph for research-grade material limits standardization across vendors.
Purity assessment relies mainly on reverse-phase high-performance liquid chromatography with ultraviolet detection. Because the peptide lacks a strong chromophore, detection often uses backbone absorbance near 214 nm. Identity is confirmed by mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, comparing the measured mass against the expected value. Amino acid analysis can verify composition after acid hydrolysis. Diastereomer content and residual counterions are reported less often, although both can influence biological assays.
Lyophilized material is generally stable for extended periods when kept dry at or below minus twenty degrees Celsius. Working solutions are less stable, and common practice is to aliquot and freeze them so that repeated freeze-thaw cycles are avoided. Aqueous solutions are sensitive to pH extremes and to microbial growth, so short-term storage at refrigerator temperature is typical. Oxidation and hydrolysis are the principal degradation routes. Reconstitution with sterile water or a mild buffer is standard, and solutions should be protected from light.
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.
=== Leaves === Average yields of 6 tons/ha/year (2 tons per acre) in fresh matter can be achieved. The harvest differs strongly between the rainy and dry seasons, with 1120 kilogram/ha (1000 lb per acre) per harvest and 690 kg/ha (620 lb per acre) per harvest, respectively. The leaves and stems can be harvested from the young plants 60 days after seeding and then another seven times in the year. At every harvest, the plants are cut back to within 60 cm (2') of the ground. In some production systems, the leaves are harvested every 2 weeks. The cultivation of M. oleifera can also be done intensively with irrigation and fertilization with suitable varieties. Trials in Nicaragua with 1 million plants per hectare and 9 cuttings/year over 4 years gave an average fresh matter production of 580 metric tons/ha/year (230 long tons per acre), equivalent to about 174 metric tons of fresh leaves.
An application of the Wittig-Still rearrangement in the context of natural product synthesis can be seen in Still's 1979 formal synthesis of the Cecropia juvenile hormone. The organotin-substituted ether that serves as the substrate for the rearrangement was readily prepared by bis-alkylation of the corresponding diol with iodomethyltributyltin. Treatment of this compound with two equivalents of n-butyllithium at low temperature resulted in transmetalation, initiating a double 2,3-sigmatropic rearrangement to give the bis-homoallylic alcohol product in 79% yield. Notably, this rearrangement is highly stereoselective with regard to the geometry of the trisubstituted olefins, giving exclusively the (Z,Z)-isomer shown.
Raymond Ashley Fulton. For services to Music in Northern Ireland. Dr. Christine Paula Futter. Lately Chief Operating Officer, Norfolk and Suffolk Care Support Ltd. For services to Adult Social Care. Jacqueline Mary Gange. Volunteer, Cannock Chase Advice Centre. For services to the community in Cannock, Staffordshire. Nicholas George Anthony Gardner. For charitable services in Scotland. William Thomas Gavan. Mayor, Sandwell Council. For Political and Public Service, and to the LGBT+ Community. Deborah Gillian Greenslade Geany. Senior Case Manager, Personnel Recovery Unit Wales and West, Ministry of Defence. For services to Military Personnel. Syed Jason Andrew Ghaboos. Deputy Director, Civil Service Employee Experience, Cabinet Office. For Public Service. Professor Panagiotis Giannoudis. Professor of Trauma and Orthopaedics, University of Leeds and Founder, Day One Trauma Support. For services to Trauma and Orthopaedic Surgery. Dr. Dinendra Singh Gill. For services to Pre-Hospital and Trauma Care in Wales. Charity Gladstone. Lately Matron of Cardiology and Respiratory Services, Gloucestershire Hospitals NHS Foundation Trust. For services to Nursing. Jill Sylvia Gladwell. Poppy Appeal Collector. For voluntary services to the Royal British Legion in Suffolk. Judith Anne Godden. Head of Casework, Constituency Office of Tim Farron MP. For services to the community in Westmorland and Lonsdale, Cumbria. Dr. Claire Mairead Goodman. Professor of Health Care Research, Centre for Research in Public Health and Community Care, University of Hertfordshire. For services to Older People.
Sources: en.wikipedia.org
Dry gas is an alcohol-based additive gas used in automobiles to prevent water from freezing in water-contaminated fuels, thereby restoring the combustive power of gasoline spoiled by water. Dry gas is added to the fuel tank and binds to the water to burn it off, and typically contains either methanol or isopropyl alcohol.
Two franchisees bought the chain in 1984 and they sold out to Inno-Pacific Holdings of Singapore in 1989. By that time, the number of franchises had declined to 221. Most of the remaining U. S. stores closed during the time Inno-Pacific owned the chain. Some of the remaining franchisees took Inno-Pacific to court in 2003. Before the case could come to trial, Shakey's was sold to Jacmar Companies of Alhambra, California in 2004. Jacmar had been the franchisee of 19 Shakey's restaurants. On September 30, 2024, SPAVI announced the incorporation of an American subsidiary that would own and operate and franchise stores in the United States. As of October 2018, there were 51 Shakey's Pizza restaurants in the United States - 48 of the locations are in California (all, except Oroville, are in Southern California), and two in Washington. The last location east of the Mississippi River, in Auburn, Alabama, closed in April 2019. The location in Renton, Washington closed on January 20, 2025, leaving Pasco as the only remaining Washington location. All locations closed their dining rooms in mid-March 2020 to combat the COVID-19 pandemic, with take-out service still available. Dining rooms re-opened in May 2021.
== Associated disorders == The most common associated disorder is pre-eclampsia, affecting approximately 7% of all births. It is characterized by a failure of the cytotrophoblast to invade the uterus and its vasculature, specifically the spiral arteries that the endovascular cytotrophoblast should invade. The result of this is decreased blood flow to the fetus which may cause intrauterine growth restriction. Clinical symptoms of pre-eclampsia in the mother are most commonly high blood pressure, proteinuria and edema. Conversely, if there is too much invasion of uterine tissue by the trophoblast then a hydatidiform mole or choriocarcinoma may arise.
Sources: en.wikipedia.org
However, in the event of a radioiodine release too massive and widespread to be controlled by the limited stock of iodide and iodate prophylaxis drugs, then the addition of perchlorate ions to the water supply, or distribution of perchlorate tablets would serve as a cheap, efficacious, second line of defense against carcinogenic radioiodine bioaccumulation. The ingestion of goitrogen drugs is, much like potassium iodide also not without its dangers, such as hypothyroidism. In all these cases however, despite the risks, the prophylaxis benefits of intervention with iodide, iodate, or perchlorate outweigh the serious cancer risk from radioiodine bioaccumulation in regions where radioiodine has sufficiently contaminated the environment.
=== Type 2 diabetes === In the BEGIN Basal-Bolus Type 2 trial, insulin degludec was studied as an alternative to insulin glargine in participants with type 2 diabetes. 995 participants were randomized to receive either insulin degludec (n=755) or insulin glargine (n=251), in addition to either mealtime insulin aspart, metformin, and/or pioglitazone. Participants in this trial had an average HbA1c of 8.3–8.4%, and 49–50% were on a regimen consisting of basal-bolus insulin plus oral antidiabetic medications. After 52 weeks, insulin degludec was found to be noninferior to insulin glargine, providing a similar HbA1c lowering effect (−1.10 vs. −1.18%). Overall rates of hypoglycemia were significantly lower with insulin degludec (11.09 vs. 13.63%/yr, p=0.0359), including cases of nocturnal hypoglycemia (1.39 vs. 1.84%/yr, p=0.0399).
The Ewe in Ghana speak three principal dialects: Anlo (along the coast), Tongu (along the Volta River) and Ewedome (in the hill country side). The Ga-Dangme occupy the Greater Accra Region and parts of the Eastern Region, while the Ewe are found in the Volta Region and the neighbouring Togo, Benin Republic and Nigeria (around Badagry area).
== History == Before automated cell counters were introduced, cell counts were performed manually; white and red blood cells, and platelets were counted using microscopes. The first person to publish microscopic observations of blood cells was Antonie van Leeuwenhoek, who reported on the appearance of red cells in a 1674 letter to the Proceedings of the Royal Society of London; Jan Swammerdam had described red blood cells some years earlier, but had not published his findings at the time. Throughout the 18th and 19th centuries, improvements in microscope technology such as achromatic lenses allowed white blood cells and platelets to be counted in unstained samples. In the 1870s, Paul Ehrlich developed a staining technique that could differentiate between the five white blood cell types. Ehrlich's stain used a combination of an acidic and basic dye to stain white and red blood cells simultaneously. Dmitri Leonidovich Romanowsky improved on this technique in the 1890s by using a mixture of eosin and aged methylene blue, which produced a wide range of hues that was not present when either of the stains was used alone. This was termed the Romanowsky effect and became the basis for Romanowsky staining, the technique that is still used to stain blood smears for manual differentials. By the early years of the 20th century, the white blood cell differential had become a common practice in the United States, but difficulties in interpreting the results cast doubt on the test's utility.
Sources: en.wikipedia.org
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.
Intranasal delivery is the route described in most published work. It is used because the peptide is degraded quickly once it reaches circulation. Direct evidence of brain penetration in humans is lacking.
Most trials are small, regionally concentrated, and often lack rigorous blinding or placebo control. Independent replication is limited. Reviews in English generally rate the evidence as preliminary.
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.