tuftsin comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-06-27. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilised solid form |
| Solubility class | Freely soluble in water | Hydrophilic heptapeptide |
| Dry storage temperature | -20 degrees Celsius or lower | Sealed, desiccated, protected from light |
| Solution storage | 2 to 8 degrees Celsius short term | Avoid repeated freeze-thaw cycles |
| Common identification method | Reversed-phase HPLC with mass spectrometry | Confirms purity and molecular mass |
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
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.
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.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
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.
== Causes == The "a calorie is a calorie" model of obesity posits a combination of excessive food energy intake and a lack of physical activity as the cause of most cases of obesity. A limited number of cases are due primarily to genetics, medical reasons, or psychiatric illness. The satiety value shows that the feeling of satiety per calorie varies between food types. Increasing rates of obesity at a societal level are felt to be due to an easily accessible and palatable diet, increased reliance on cars, and mechanized manufacturing. Some other factors have been proposed as causes towards rising rates of obesity worldwide, including insufficient sleep, endocrine disruptors, increased usage of certain medications (such as atypical antipsychotics), increases in ambient temperature, decreased rates of smoking, demographic changes, increasing maternal age of first-time mothers, changes to epigenetic regulation from the environment, increased phenotypic variance via assortative mating, social pressure to diet, among others. According to one study in 2006, factors like these may play as big of a role as excessive food energy intake and a lack of physical activity; however, the relative magnitudes of the effects of any proposed cause of obesity is varied and uncertain, as there is a general need for randomized controlled trials on humans before definitive statement can be made.
== Premise == It takes place after a 1980 plane crash claims America's Olympic boxing team. It shows a determined coach taking on the monumental task of assembling and training new fighters for glory at the 1984 Summer Olympics.
The polysaccharide synthesis operon and cyclic di-GMP form a positive feedback loop. This 15-gene operon is responsible for the cell-cell and cell-surface interactions required for cell communication. PEL is a cationic exopolysaccharide that cross-links extracellular DNA in the P. aeruginosa biofilm matrix. Upon certain cues or stresses, P. aeruginosa revert the biofilm program and detach. Recent studies have shown that the dispersed cells from P. aeruginosa biofilms have lower cyclic di-GMP levels and different physiologies from those of planktonic and biofilm cells, with unique population dynamics and motility. Such dispersed cells are found to be highly virulent against macrophages and C. elegans, but highly sensitive towards iron stress, as compared with planktonic cells.
Beta-adrenergic receptors (β1, β2, β3) stimulate lipolysis through Gs-protein-coupled activation of adenylyl cyclase and subsequent cAMP production, while alpha-2 adrenergic receptors (α2A) inhibit lipolysis through Gi-protein-mediated suppression of adenylyl cyclase. Subcutaneous abdominal adipose tissue exhibits a higher α2:β ratio compared to visceral adipose tissue, which is predominantly β3-receptor-expressing and more lipolytically responsive to catecholamine stimulation.
Sources: en.wikipedia.org
McClements, David Julian (2023). "Bug Meat: Assembling Meat from Insects". Meat Less: The Next Food Revolution. Copernicus Books. Cham: Springer. pp. 185–212. doi:10.1007/978-3-031-23961-8_8. ISBN 978-3-031-23961-8. FAO (2021): Looking at edible insects from a food safety perspective. Challenges and opportunities for the sector. Rome. doi: https://doi.org/10.4060/cb4094en van Huis/Tomberlin (2017). Insects As Food and Feed: From Production to Consumption. Wageningen Academic Publishers. ISBN 978-90-8686-296-2. Dossey, Morales-Ramos and Rojas. Insects as Sustainable Food Ingredients: Production, Processing and Food Applications. Archived from the original on 2020-07-03. Retrieved 2018-10-24. {{cite book}}: |work= ignored (help) Shockley and Dossey (2014). "Insects for Human Consumption". Mass Production of Beneficial Organisms: 617–652. doi:10.1016/B978-0-12-391453-8.00018-2. ISBN 978-0-12-391453-8.{{cite journal}}: CS1 maint: periodical has ISBN (link) Calder, Daniel. The Dietitian's Guide to Eating Bugs 2013 ebook [2] Archived 2016-05-09 at the Wayback Machine Dossey, Aaron (2013). "Why Insects Should Be in Your Diet". The Scientist. 27: 22–23.
=== Relapse === Rates of relapse after treatment range 30–72% over a period of 2–26 months, with a rate of approximately 50% in 12 months after weight restoration. Relapse occurs in approximately a third of people in hospital, and is greatest in the first six to eighteen months after release from an institution. BMI or measures of body fat and leptin levels at discharge were the strongest predictors of relapse, as well as signs of eating psychopathology at discharge. Duration of illness, age, severity, the proportion of AN binge-purge subtype, and presence of comorbidities are also contributing factors.
According to Smith's account, "each one, quietly but firmly, without hesitation, said: 'Yes'." At 11:00 local time on 11 November 1965, Armistice Day, during the traditional two minutes' silence to remember the fallen of the two World Wars, Smith declared Rhodesia independent and signed the proclamation document, with Dupont and the other 10 ministers of the Cabinet following. The timing was intended to emphasise the sacrifices Rhodesia had made for Britain in wartime. As Ken Flower later said, "the rebellion was made to appear as though it was not a rebellion". Smith and his ministers still pledged allegiance to Queen Elizabeth II, whose official portrait hung prominently behind them as they signed; the declaration even ended "God Save The Queen". Four junior members of the Cabinet—Lance Smith, Ian Dillon, Andrew Dunlop and P. K. van der Byl—did not sign, but were included in the official photograph.
Sources: en.wikipedia.org
On 11 September 2008, fresh reports of massive outbreak of melamine contamination found in China led to recall of infant formula products in China. Some Chinese reports said the manufacturer of the milk products might not have consciously added Melamine to their powdered milk, however they could have used a soy protein substitute to lower production costs, and the source of their soy substitute had melamine added to it. Many Chinese babies had developed kidney stones and other acute kidney problems in recent months across China, investigation led to the discovery of this contaminant. Some people were wondering how much melamine has already entered food products designated for adults without discovery. More worrying are claims reported in China that there are now new chemicals that can be added to food to lower production costs, and yet pass the tests for melamine and other related chemicals. Impact of this incident to dairy industry outside China is beginning to unravel. By the end of September 2008, the Chinese government said that 22 dairy companies, including Sanlu and export brands like Mengniu and Yili, had produced powdered baby formula that contained traces of melamine. Some dairy farmers interviewed in Hebei Province said it was an open secret that milk was adulterated. Some dairies routinely watered down milk to increase profits, then added other cheap ingredients so the milk could pass a protein test.
== History == The first flame ionization detectors were developed simultaneously and independently in 1957 by McWilliam and Dewar at Imperial Chemical Industries of Australia and New Zealand (ICIANZ, see Orica history) Central Research Laboratory, Ascot Vale, Melbourne, Australia and by Harley and Pretorius at the University of Pretoria in Pretoria, South Africa. In 1959, Perkin Elmer Corp. included a flame ionization detector in its Vapor Fractometer.
Some scholars believe Christian elements are deeply embedded in Druze beliefs, introduced through Isma'ili traditions. This is evident in the Druze creed, which deifies al-Hākim bi Amrillāh. The initiation text, "Mīthāq Walī al-Zamān" (Pact of Time Custodian), which begins with, "I rely on our Moula Al-Hakim the lonely God, the individual, the eternal,... Obedience of almighty Moulana Al-Hākim, exalted be him and that obedience is worship and that he does not have any partners ever, present or coming", closely resembles Christian beliefs about Jesus' divinity. The Druze also view figures like Jesus, al-Hākim bi Amrillāh, and Hamza ibn Ali as the Messiah or Mahdi. They believe al-Hākim will return at the end of times to judge the world and establish his kingdom, while Hamza ibn Ali is considered a reincarnation of Jesus, the Universal Mind 'Aql, closely associated with al-Hākim. Druze doctrine regards Christianity, Judaism, and Islam as preceding religions that embody different manifestations of Druzism, which they consider superior to all. According to Druze beliefs, Adam and Jesus hold a unique status among prophets, sharing in divine essence. The Druze conception of Jesus ('Īsa ibn-Yūsuf) differs somewhat from the portrayal in the New Testament; he resembles the Muslim interpretation of Jesus as envisioned by the ancient Docetae sect, who believed that Christ suffered only in appearance. Christian influences are evident in the writings of the Druze missionary Baha al-Din al-Muqtana (d. 1042).
Nasal skeleton Therefore, the successful rhinoplastic outcome depends entirely upon the respective maintenance or restoration of the anatomic integrity of the nasal skeleton, which comprises (a) the nasal bones and the ascending processes of the maxilla in the upper third; (b) the paired upper-lateral cartilages in the middle third; and (c) the lower-lateral, alar cartilages in the lower third. Hence, managing the surgical reconstruction of a damaged, defective, or deformed nose, requires that the plastic surgeon manipulate three anatomic layers:
Sources: en.wikipedia.org
Dry powder is normally held at -20 degrees Celsius or below in a sealed, light-protected container with desiccant. Brief room-temperature handling during weighing is generally tolerated. Storage instructions vary between suppliers, so the accompanying certificate of analysis should be followed.
Reversed-phase HPLC establishes purity, while mass spectrometry confirms the expected molecular mass. Sequence confirmation may use tandem mass spectrometry or peptide mapping. A certificate of analysis typically reports these results alongside the analytical method applied.
In Russia it is a registered medicine available by prescription. In many other countries it is not approved for human use and is supplied only as a research chemical. Import and possession rules differ by jurisdiction, and buyers are responsible for checking local requirements.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, designed as a metabolically stabilized analogue of the endogenous tetrapeptide tuftsin. It has been studied mainly against anxiety-related and cognitive endpoints rather than as an approved medicine in most jurisdictions.