anxiolytic raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-11-10. Anything still debated is marked as such rather than presented as settled.
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.
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.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Calculated for the free peptide |
| Molecular weight | About 751.9 g/mol | Derived from the sequence |
| Appearance | White to off-white powder | Typical lyophilised form |
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
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.
Reported activity for Selank centers on anxiolytic and nootropic effects. Russian clinical reports describe use in anxiety and in cognitive or attention-related complaints. Most of this evidence comes from studies conducted by the same research groups that developed the peptide. Independent replication in other countries remains limited, and no major Western regulatory agency has approved the compound for any indication. The gap between local reports and external verification is a recurring point in discussions of the peptide.
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.
== Detection == Separation by capillary electrophoresis can be detected by several detection devices. The majority of commercial systems use UV or UV-Vis absorbance as their primary mode of detection. In these systems, a section of the capillary itself is used as the detection cell. The use of on-tube detection enables detection of separated analytes with no loss of resolution. In general, capillaries used in capillary electrophoresis are coated with a polymer (frequently polyimide or Teflon) for increased flexibility. The portion of the capillary used for UV detection, however, must be optically transparent. For polyimide-coated capillaries, a segment of the coating is typically burned or scraped off to provide a bare window several millimeters long. This bare section of capillary can break easily, and capillaries with transparent coatings are available to increase the stability of the cell window. The path length of the detection cell in capillary electrophoresis (~ 50 micrometers) is far less than that of a traditional UV cell (~ 1 cm). According to the Beer-Lambert law, the sensitivity of the detector is proportional to the path length of the cell. To improve the sensitivity, the path length can be increased, though this results in a loss of resolution. The capillary tube itself can be expanded at the detection point, creating a "bubble cell" with a longer path length or additional tubing can be added at the detection point as shown in figure 2. Both of these methods, however, will decrease the resolution of the separation.
=== Thermal stability === The melting point of sucrose esters is between 40 °C and 60 °C depending on the type of fatty acids and the degree of substitution. Sucrose esters can be heated to 185 °C without losing their functionality. However, the color of the product might change due to caramelization of sucrose.
Pharmacometabolomics, also known as pharmacometabonomics, is a field which stems from metabolomics, the quantification and analysis of metabolites produced by the body. It refers to the direct measurement of metabolites in an individual's bodily fluids, in order to predict or evaluate the metabolism of pharmaceutical compounds, and to better understand the pharmacokinetic profile of a drug. Alternatively, pharmacometabolomics can be applied to measure metabolite levels following the administration of a pharmaceutical compound, in order to monitor the effects of the compound on certain metabolic pathways(pharmacodynamics). This provides detailed mapping of drug effects on metabolism and the pathways that are implicated in mechanism of variation of response to treatment. In addition, the metabolic profile of an individual at baseline (metabotype) provides information about how individuals respond to treatment and highlights heterogeneity within a disease state. All three approaches require the quantification of metabolites found in bodily fluids and tissue, such as blood or urine, and can be used in the assessment of pharmaceutical treatment options for numerous disease states.
the vaccination program is not successful in eradicating the disease, on the contrary, it will remain endemic, although at lower levels than the case of absence of vaccinations. This means that the mathematical model suggests that for a disease whose basic reproduction number may be as high as 18 one should vaccinate at least 94.4% of newborns in order to eradicate the disease.
29 September The kārearea is named Bird of the Year for 2025. The government announces a reform of the earthquake-prone building classification system which reduces the amount of buildings nationwide being classed as earthquake-prone by 55%. 30 September: Carter Holt Harvey confirms plans to close its Tokoroa plywood plant in November 2025, affecting 119 jobs. A measles case linked to international travel is reported in Queenstown, bringing the total number of cases to five.
Sources: en.wikipedia.org
=== SPR emission === When the surface plasmon wave interacts with a local particle or irregularity, such as a rough surface, part of the energy can be re-emitted as light. This emitted light can be detected behind the metal film from various directions.
== Personal life == In 1971, Parsons married Gretchen Burrell (née Gretchen Lisl Berrill) at his stepfather's New Orleans estate. Parsons and Burrell went to England, where they visited their friend Ric Grech. With the help of Grech and his friend Hank Wangford, Parsons stopped using heroin. In the summer of 1973, Parsons' Topanga Canyon home burned to the ground, the result of a stray cigarette. Nearly all of his possessions were destroyed with the exception of a guitar and a prized Jaguar. The fire proved to be the last straw in the relationship between Burrell and Parsons, who moved into a spare room in Kaufman's house. Parsons rekindled his relationship with Margaret Fisher, a high school sweetheart from Waycross. Parsons had one child, born to Nancy Ross in 1967, Polly Parsons.
== External links == Picot, J; Hartwell, D; Harris, P; Mendes, D; Clegg, A J; Takeda, A (2012). "The effectiveness of interventions to treat severe acute malnutrition in young children: a systematic review". Health Technology Assessment. 16 (19): 1–316. doi:10.3310/hta16190. PMC 4781582. PMID 22480797. NBK98566. Media related to Kwashiorkor at Wikimedia Commons The dictionary definition of kwashiorkor at Wiktionary
American Society for Pharmacology and Experimental Therapeutics British Pharmacological Society International Conference on Harmonisation US Pharmacopeia International Union of Basic and Clinical Pharmacology IUPHAR Committee on Receptor Nomenclature and Drug Classification IUPHAR/BPS Guide to Pharmacology
The underlined nucleotides indicate the translation start codon, coding for Methionine. upper-case letters indicate highly conserved bases, i.e. the 'AUGG' sequence is constant or rarely, if ever, changes. 'R' indicates that a purine (adenine or guanine) is always observed at this position (with adenine being more frequent according to Kozak) a lower-case letter denotes the most common base at a position where the base can nevertheless vary the sequence in parentheses (gcc) is of uncertain significance. The AUG is the initiation codon encoding a methionine amino acid at the N-terminus of the protein. (Rarely, GUG is used as an initiation codon, but methionine is still the first amino acid as it is the met-tRNA in the initiation complex that binds to the mRNA). Variation within the Kozak sequence alters the "strength" thereof. Kozak sequence strength refers to the favorability of initiation, affecting how much protein is synthesized from a given mRNA. The A nucleotide of the "AUG" is delineated as +1 in mRNA sequences with the preceding base being labeled as −1, i.e. there is no 0 position. For a 'strong' consensus, the nucleotides at positions +4 (i.e. G in the consensus) and −3 (i.e. either A or G in the consensus) relative to the +1 nucleotide must both match the consensus. An 'adequate' consensus has only 1 of these sites, while a 'weak' consensus has neither. The cc at −1 and −2 are not as conserved, but contribute to the overall strength. There is also evidence that a G in the -6 position is important in the initiation of translation.
Sources: en.wikipedia.org
=== Conformation === The protonated form of methadone takes on an extended conformation, while the free base is more compact. In particular, it was found that there is an interaction between the tertiary amine and the carbonyl carbon of the ketone function (R3N ••• >C=O) that limits the molecule's conformation freedom, though the distance (291 pm by X-ray) is far too long to represent a true chemical bond. However, it does represent the initial trajectory of attack of an amine on a carbonyl group and was an important piece of experimental evidence for the proposal of the Bürgi–Dunitz angle for carbonyl addition reactions.
== Effects == Unlike other KOR agonists, nalfurafine does not produce hallucinogenic effects in humans. Single intramuscular injections of up to 30 μg are well tolerated by humans, whereas a dose of 40 μg produced "moderate behavioral/psychological side effects" (possibly referring to sedation), though apparently did not produce any psychotomimetic or dysphoric effects. In rodents, a low dose of nalfurafine (10–40 μg/kg) was found not to produce conditioned place preference or aversion, though a high dose (80 μg/kg) did induce significant place aversion. The most common side effect of low-dose nalfurafine seen in clinical trials was insomnia (observed in 10–15% of patients), with few other adverse effects observed. In addition, tolerance to the antipruritic effects of nalfurafine was not found after treatment of patients with the drug for one year, and nalfurafine has shown no evidence of either physical nor psychological dependence in humans. The drug also shows lower evidence of tolerance for effects such as analgesia and sedation in animals relative to other KOR agonists. In animals, nalfurafine produces anti-scratch, antinociceptive, sedative, and diuretic effects.
The majority of Hetero’s workforce is under 50, with 48.39% of employees aged 30-50 and another 50% under 30. Gender pays ratios ranged from 0.86:1 to 0.97:1 across management levels, reaching parity (1:1) for contract workers. Mahila Abhyudaya Hetero runs a program called Mahila Abhyudaya aimed at integrating women into production roles historically dominated by men, alongside dedicated women’s walk-in recruitment drives. The company reported zero POSH (prevention of sexual harassment) cases and zero incidents of discrimination on any basis during FY 2024-25. All employees are eligible for parental leave. 514 men and 64 women took parental leave during the year, with a 100% return to work rate and 100% 12 month retention rate. Employees received a total of 901175 hours of training during the year, averaging 44/88 hours per employee and 14.12 hours per contract worker. Training is split into roughly 54% Good Manufacturing Practices, 30% safety, and 16% learning and development content. Hetero operates several structured programs for employee training, including Manthan: technical/ functional skills, using AR/VR training technology Pragati: leadership and behavioral skills across three tiers Sammati: compliance training on ethics, safety and green chemistry Unnati: talent development and social outreach Bharosa: mental health and wellness A dedicated Nipuna training center and Darpan skill development centre support technical upskilling and bridge the academia-industry gaps. All employees receive a formal performance and career development review during the year.
In this method, polyvinylpyrrolidone (PVP) is dissolved in water by sonication and mixed with silver colloid particles. Active stirring ensures the PVP has adsorbed to the nanoparticle surface. Centrifuging separates the PVP coated nanoparticles which are then transferred to a solution of ethanol to be centrifuged further and placed in a solution of ammonia, ethanol and Si(OEt4) (TES). Stirring for twelve hours results in the silica shell being formed consisting of a surrounding layer of silicon oxide with an ether linkage available to add functionality. Varying the amount of TES allows for different thicknesses of shells formed. This technique is popular due to the ability to add a variety of functionality to the exposed silica surface.
Venus was of great interest in the field of planetary science due to its thick and opaque atmosphere, the atmospheres of other planets being a novel area of research at the time. In 1961 the Venera Programme was initiated by the Soviet Union, with the launch of Venera 1. The programme would go on to mark many firsts in the exploration of another planet. Despite the later successes however, Venera 1 and Venera 2, intended to flyby Venus, resulted in failure due to losses of contact. NASA would then initiate the Mariner program with the launch of Mariner 1 and Mariner 2. Mariner 1 failed shortly after launch, however Mariner 2 would become the first man-made object to flyby another planet in December 1962 when the probe passed by Venus. Later in 1965/66, Venera 3, marked the first time a man-made object made contact with another planet after it impacted Venus on March 1, 1966, despite operational difficulties resulting in loss of contact with the craft. In 1967, Mariner 5 flew by Venus and conducted atmospheric analysis.
Sources: en.wikipedia.org
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, commonly written as TKPRPGP. It shares the first four residues with tuftsin and carries three prolines in the chain. The proline-rich tail is the main structural feature that separates it from the parent tetrapeptide.
Selank is a synthetic analogue built on the tuftsin tetrapeptide Thr-Lys-Pro-Arg. Extra proline residues were added to the C-terminus during design work. That modification is intended to make the peptide less vulnerable to rapid enzymatic degradation.
Transliteration from Russian produces variant spellings such as Selanc. Many suppliers avoid the trade-style name entirely and list the peptide sequence. Comparing sequences rather than names is the reliable way to confirm two entries describe the same molecule.
Sealed, desiccated storage at -20 °C or colder is the standard recommendation for research-grade material. Vials should reach room temperature before they are opened, which limits condensation. Repeated temperature cycling is discouraged.