The short version of tuftsin fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-07-24. Anything still debated is marked as such rather than presented as settled.
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.
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.
Quality assessment of Selank samples typically combines purity determination with identity confirmation and counter-ion analysis. Purity is usually reported as a percentage by chromatographic area, with values above 95 percent often quoted for research-grade material. Water content and residual solvents are checked in lyophilized batches because they affect both stability and accurate mass determination. A reported purity figure does not by itself establish that a sample is the intended sequence, so orthogonal methods are needed to rule out sequence isomers or truncation products.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Free peptide form |
| Molecular mass | About 751.9 Da | Calculated average mass |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form TKPRPGP |
| Structural basis | Tuftsin analogue | Extended version of a natural tetrapeptide |
| Development origin | Russian Academy of Sciences | Work carried out from the 1980s onward |
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.
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.
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.
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.
Asian citrus psyllid on the UF / IFAS Featured Creatures Web site Species Profile – Citrus Greening and Species Profile – Asian Citrus Psyllid, National Invasive Species Information Center, National Agricultural Library. Lists general information and resources for citrus greening and the Asian citrus psyllid. CISR: Huanglongbing/Citrus Greening Center for Invasive Species Research page on Huanglongbing and Citrus Greening
Small-scale cultivation of P. cubensis is often accomplished with "cakes" that colonize within jars, but fruit inside specially designed tubs called "shotgun fruiting chambers". The most common cake method for beginners is PF-Tek ("Psilocybe Fanaticus technique"), named after Psylocybe Fanaticus, the clandestine cultivator credited for its creation. Cakes are popular for the new cultivator because of their simplicity and low cost of startup materials. As cakes are composed of brown rice flour, vermiculite, and gypsum, they can be steam-sterilized in a large pot. Unlike cereal grains used in bulk growing, brown rice flour contains no bacterial endospores, a contamination vector requiring a pressure cooker to sterilize. The "Uncle Ben's Tek", also known as Spiderman Tek and Instant Rice Tek, is a growing method using microwavable rice sachets. This technique involves utilizing pre-sterilized rice bags for mycelium to colonize upon. Though Uncle Ben's Tek is largely popular among beginners due to its low cost, it faces criticism from those more experienced due to its high rate of contamination compared to other techniques. Other Teks exist, such as Lemon-Tek and Bucket-Tek, though all Tek's do not refer to methods for growth. Rather, they refer to knowledge regarding the cultivation, harvest, processing, and consumption for psychedelic fungi. TEK stands for Traditional Ecological Knowledge, though others claim it stands for Time Experience Knowledge or is simply a shortening of the term 'technique'.
THAP, DHAP, and a mixture of 2-aza-2-thiothymine and phenylhydrazine have been identified as matrices that could be used to minimize loss of sialic acid during MALDI MS analysis of glycosylated peptides. It has been reported that a reduction in loss of some post-translational modifications can be accomplished if IR MALDI is used instead of UV MALDI. Besides proteins, MALDI-TOF has also been applied to study lipids. For example, it has been applied to study the catalytic reactions of phospholipases. In addition to lipids, oligonucleotides have also been characterised by MALDI-TOF. For example, in molecular biology, a mixture of 5-methoxysalicylic acid and spermine can be used as a matrix for oligonucleotides analysis in MALDI mass spectrometry, for instance after oligonucleotide synthesis.
=== Acrylamide controversy === Heating a mixture of asparagine and reducing sugars or other source of carbonyls produces acrylamide in food. These products occur in baked goods such as French fries, potato chips, and toasted bread. Acrylamide is converted in the liver to glycidamide, which is a possible carcinogen.
=== Abuse of Coalition POWs === During the conflict, coalition aircrew shot down over Iraq were displayed as prisoners of war on TV, most with visible signs of abuse. Amongst several testimonies to poor treatment, USAF Captain Richard Storr was allegedly tortured by Iraqis during the Persian Gulf War. Iraqi secret police broke his nose, dislocated his shoulder and punctured his eardrum. Royal Air Force Tornado crew John Nichol and John Peters have both alleged that they were tortured during this time. Nichol and Peters were forced to make statements against the war on television. Members of British Special Air Service Bravo Two Zero were captured while providing information about an Iraqi supply line of Scud missiles to coalition forces. Only one, Chris Ryan, evaded capture while the group's other surviving members were violently tortured. Flight surgeon (later General) Rhonda Cornum was sexually assaulted by one of her captors after the Black Hawk helicopter in which she was riding was shot down while searching for a downed F-16 pilot.
Sources: en.wikipedia.org
=== Mating === When ready to mate, cabbage loopers display by elevating their abdomen and fanning their wings. Males also fan out their abdominal hairs, open their genital claspers, and partially stick out their spermatophores. Males gradually expose more of their spermatophores as they wait for a mate. Upon interest, a potential mate examines the other's abdomen with antennae, and mating occurs if both agree. Mating on average occurs at 2am, but has been observed occurring between 12 and 4am. Mating generally occurs 3–4 days after emergence, but can occur up to 16 days afterwards. Usually, mating does not occur before the third day, as eggs are not fully developed upon emergence and require a few days to reach maturity. Multiple matings is a mating strategy where individuals have multiple mates in their lifetime. This is in contrast to monogamy, where individuals have one mate for life. Mating multiply can be advantageous to both sexes, which is why this strategy has evolved in many species, including the cabbage looper. For female cabbage loopers, rate of oviposition increases with the number of matings, and ultimately lay more eggs total. While it was once believed that multiple matings were necessary to fertilize all eggs, evidence shows that only one mating is needed to fertilize almost all eggs. Instead, it is more likely that the spermatophore provides nutrients to the female that confers reproductive benefits. This may explain why males produce female-attracting pheromones, as females may be seeking nutrient-rich spermatophores.
=== Death === De Duve died on 4 May 2013, at his home in Nethen, Belgium, aged 95. He decided to end his life by legal euthanasia, performed by two doctors and in the presence of his four children. He had been long suffering from cancer and atrial fibrillation, and his health problems were exacerbated by a recent fall in his home. De Duve was cremated as he had willed, and his ashes were distributed among family members and friends.
=== EC 1.3.8 With a flavin as acceptor === EC 1.3.8.1: short-chain acyl-CoA dehydrogenase EC 1.3.8.2: 4,4′-diapophytoene desaturase (4,4′-diapolycopene-forming) EC 1.3.8.3: (R)-benzylsuccinyl-CoA dehydrogenase EC 1.3.8.4: isovaleryl-CoA dehydrogenase EC 1.3.8.5: 2-methyl-branched-chain-enoyl-CoA reductase EC 1.3.8.6: glutaryl-CoA dehydrogenase (ETF) EC 1.3.8.7: medium-chain acyl-CoA dehydrogenase EC 1.3.8.8: long-chain acyl-CoA dehydrogenase EC 1.3.8.9: very-long-chain acyl-CoA dehydrogenase EC 1.3.8.10: cyclohex-1-ene-1-carbonyl-CoA dehydrogenase EC 1.3.8.11: cyclohexane-1-carbonyl-CoA dehydrogenase (electron-transfer flavoprotein) EC 1.3.8.12: (2S)-methylsuccinyl-CoA dehydrogenase EC 1.3.8.13: crotonobetainyl-CoA reductase EC 1.3.8.14: L-prolyl-[peptidyl-carrier protein] dehydrogenase EC 1.3.8.15: 3-(aryl)acrylate reductase EC 1.3.8.16: 2-amino-4-deoxychorismate dehydrogenase EC 1.3.8.17: dehydro coenzyme F420 reductase
=== Apical Constriction and Cementodentinal Junction === The apical constriction is a narrowing of the canal just coronal to the foramen and serves as a histological landmark for endodontic procedures. The cementodentinal junction (CDJ) is located near the apex where cementum meets dentin.
Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment. Water treatment removes contaminants and undesirable components, or reduces their concentration so that the water becomes fit for its desired end-use. This treatment is crucial to human health and allows humans to benefit from both drinking and irrigation use. Advanced water treatment methods have been developed in recent decades due to increased concerns about new pollutants like microplastics, pharmaceuticals, and per- and polyfluoroalkyl substances (PFAS). These include advanced oxidation processes, membrane filtration, and adsorption-based techniques utilizing materials like tailored nanomaterials and activated carbon. Additionally, energy efficiency, resource recovery, and sustainability in water treatment systems are receiving more attention, especially in areas where water is scarce and environmental demands are growing.
Sources: en.wikipedia.org
It is a seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, produced by chemical synthesis rather than extracted from biological tissue. Its design is based on tuftsin, a natural immunomodulatory tetrapeptide. The C-terminal Pro-Gly-Pro segment is a common stabilising motif in short regulatory peptides.
The core four residues correspond to tuftsin, which occurs naturally as part of immunoglobulin G. The full seven-residue sequence, however, is not a known endogenous peptide. It is a laboratory-designed analogue intended to combine tuftsin-like activity with greater resistance to breakdown.
No single receptor has been confirmed as the primary target. Reports describe involvement of the GABAergic system, interference with enkephalin degradation, and shifts in neurotrophic factor expression. Because these observations come from different models and assays, they have not yet been integrated into one accepted mechanism.
The most common approach combines reverse-phase liquid chromatography with mass spectrometry. Chromatography separates the components while mass spectrometry confirms the molecular mass. Peptide sequencing or tandem mass analysis can further verify the amino acid order.