Everything below concerns Pro-Gly-Pro. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-01-10. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Derived from the seven-residue sequence |
| Molecular weight | About 751.9 g/mol | Average mass; the monoisotopic value is slightly lower |
| Residue count | Seven amino acids | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Parent compound | Tuftsin (Thr-Lys-Pro-Arg) | Selank extends tuftsin at the C-terminus |
| Compound class | Synthetic short peptide | Studied in a research setting; not a licensed drug in most markets |
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.
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.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
A number of factors, including diet, obesity, and exercise, affect the level of deoxycholate in the human colon. When humans were switched from their usual diet to a meat, egg and cheese based diet for five days, deoxycholate in their feces increased by factors of 2 to 10 fold. Rats fed diets with 30% beef tallow (high fat) had almost 2-fold more deoxycholate in their feces than rats fed 5% beef tallow (low fat). In the same study, adding the further dietary elements of curcumin or caffeic acid to the rats' high fat (30% beef tallow) diet reduced the deoxycholate in their feces to levels comparable to levels seen in the rats on a low fat diet. Curcumin is a component of the spice turmeric, and caffeic acid is a component high in some fruits and spices. Caffeic acid is also a digestive break-down product of chlorogenic acid, high in coffee and some fruits and vegetables. In addition to fats, the type or amount of protein in the diet may also affect bile acid levels. Switching from a diet with protein provided by casein to a diet with protein provided by salmon protein hydrolysate led to as much as a 6-fold increase in levels of bile acids in the blood plasma of rats. In humans, adding high protein to a high fat diet raised the level of deoxycholate in the plasma by almost 50%. Obesity has been linked to cancer, and this link is in part through deoxycholate.
Another perspective hypothesis suggests that electromagnetic fields increase in adenosine receptors release, which facilitates neuronal communication. Because A(2A) adenosine receptors control the release of other neurotransmitters (e.g., glutamate and dopamine), this contributes to adjusting neuronal functions. According to the natural neurostimulation hypothesis, energy stimuli induce mitochondrial stress and microvascular vasodilation. These promote increasing Adenosine triphosphate (ATP) protein and oxygenation, inducing synaptic strength. This position explains neuromodulation from different scale levels: from interpersonal dynamics to nonlocal neuronal coupling. According to natural neurostimulation, the innate natural mechanism of physical interactions between the mother and embryo ensures the balanced development of the embryonic nervous system. The drivers of these interactions, the electromagnetic properties of the mother's heart, enable brain waves to interact between the mother's and fetal nervous systems. The electromagnetic and acoustic oscillations of the mother's heart converge the neuronal activity of both nervous systems in an ensemble, shaping harmony from a cacophony of separate oscillations. These interactions synchronize brain oscillations, influencing neuroplasticity in the fetus. During the mother's intentional actions with her environment, these interchanges provide hints to the fetus's nervous system, binding synaptic activity with relevant stimuli.
=== Personal care products === Personal care products often contain a complex mixture of chemicals such as preservatives (e.g., parabens), UV filters (e.g., oxybenzone), plasticizers (e.g., phthalates), antimicrobials (e.g., triclosan), fragrances, and colorants. Many of these compounds are synthesized chemicals that are not typically found in nature. Chemicals from personal care products can enter the environment through various pathways. After use, they are often washed down the drain and can end up in the wastewater stream. These substances are not all completely removed by conventional wastewater treatment processes, leading to their release into natural water bodies. Some of these chemicals are persistent in the environment and can bioaccumulate in the tissues of organisms, potentially causing ecological disruptions. They can also have endocrine-disrupting properties that interfere with the hormonal systems of wildlife and humans.
== Author == Fascia: The Tensional Network of the Human Body: The science and clinical applications in manual and movement therapy. Elsevier Health Sciences. 26 February 2013. ISBN 978-0-7020-5228-6. Fascia in Sport and Movement. Handspring. 2015. ISBN 978-1-909141-07-0. Fascial Fitness: How to be Vital, Elastic and Dynamic in Everyday Life and Sport. Lotus. 2017. ISBN 978-1-905367-71-9. Fascia: The Tensional Network of the Human Body Expert Consult: Fascia: The Tensional Network of the Human Body - E-Book. Elsevier Health Sciences. 8 December 2021. ISBN 978-0-7020-8413-3. Fascial Fitness, Second Edition: Practical Exercises to Stay Flexible, Active and Pain Free in Just 20 Minutes a Week. North Atlantic Books. 6 July 2021. ISBN 978-1-62317-675-4. Fascia in Sport and Movement, Second edition. Jessica Kingsley Publishers. 30 March 2021. ISBN 978-1-912085-78-1. Der Faszien-Code: Wie die Genetik des Bindegewebes deine Gesundheit beeinflusst und du typgerecht trainierst, um Beweglichkeit und Fitness zu optimieren. Riva Verlag. 18 February 2024. ISBN 978-3-7453-2298-9.
Sources: en.wikipedia.org
Some molecules have simple spectra which are easy to identify, whilst others (even some small molecules) have extremely complex spectra with flux spread among many different lines, making them far harder to detect. Interactions between the atomic nuclei and the electrons sometimes cause further hyperfine structure of the spectral lines. If the molecule exists in multiple isotopologues (versions containing different atomic isotopes), the spectrum is further complicated by isotope shifts. Detection of a new interstellar or circumstellar molecule requires identifying a suitable astronomical object where it is likely to be present, then observing it with a telescope equipped with a spectrograph working at the required wavelength, spectral resolution and sensitivity. The first molecule detected in the interstellar medium was the methylidyne radical (CH•) in 1937, through its strong electronic transition at 4300 angstroms (in the optical). Advances in astronomical instrumentation have led to increasing numbers of new detections. From the 1950s onwards, radio astronomy began to dominate new detections, with sub-mm astronomy also becoming important from the 1990s. The inventory of detected molecules is highly biased towards certain types which are easier to detect. For example, radio astronomy is most sensitive to small linear molecules with a high molecular dipole.
== Biography == Langevin received an MD degree from McGill University in 1978. She did a post doctoral research fellowship in Neurochemistry at the MRC Neurochemical Pharmacology Unit in Cambridge, England, a residency in Internal Medicine and a fellowship in Endocrinology and Metabolism at Johns Hopkins Hospital. She was a Professor in Residence of Medicine at Harvard Medical School, Brigham and Women's Hospital. She was also a part-time Professor of Neurology, Orthopedics and Rehabilitation at the University of Vermont College of Medicine. She was the Principal Investigator of two NIH-funded studies investigating the role of connective tissue in low back pain and the mechanisms of manual and movement based therapies. Her previous studies in humans and animal models have found that "needle grasp", the biomechanical component of de qi, may be caused by connective tissue winding around the needle. Helene Langevin was appointed as Director of the Osher Center for Integrative Medicine at Harvard Medical School and Brigham and Women's Hospital in November 2012.
A very important modification of eukaryotic pre-mRNA is RNA splicing. The majority of eukaryotic pre-mRNAs consist of alternating segments called exons and introns. During the process of splicing, an RNA-protein catalytical complex known as spliceosome catalyzes two transesterification reactions, which remove an intron and release it in form of lariat structure, and then splice neighbouring exons together. In certain cases, some introns or exons can be either removed or retained in mature mRNA. This so-called alternative splicing creates series of different transcripts originating from a single gene. Because these transcripts can be potentially translated into different proteins, splicing extends the complexity of eukaryotic gene expression and the size of a species proteome. Extensive RNA processing may be an evolutionary advantage made possible by the nucleus of eukaryotes. In prokaryotes, transcription and translation happen together, whilst in eukaryotes, the nuclear membrane separates the two processes, giving time for RNA processing to occur.
==== Arrhenoblastoma ==== Arrhenoblastoma is an uncommon tumor of the ovary. It is composed of sterol cells, Leydig cells, or some combination of the two. The tumor can produce male or female hormones and may cause masculinization. In a prepubescent child, a tumor may cause precocious puberty. Malignant arrhenoblastoma accounts for 30% of cases of arrhenoblastoma, the other 70% being largely benign and curable with surgery.
== Professional and political career == He was into real estate business on large scale in and around Hyderabad. He was a successful businessman and was paying IT returns of 9 lakhs and 12 lakhs per annum in 2012–13 and 2013–14. He does not have any criminal cases pending against him as of 2014. After the reconstitution of constituencies in 2009 and subsequent defeat of TDP in Repalle, probable retirement of Mummaneni Venkata Subbaih (Then TDP candidate) brought Anagani Satya Prasad into the political arena. The decision of TDP to allot 100 seats to BCs then was an enabling factor for him. In 2009 he contested the elections but lost. But he emerged victorious in the 2014 and 2019 elections.
Sources: en.wikipedia.org
Once the substrate is bound and oriented to the active site, catalysis can begin. The residues of the catalytic site are typically very close to the binding site, and some residues can have dual-roles in both binding and catalysis. Catalytic residues of the site interact with the substrate to lower the activation energy of a reaction and thereby make it proceed faster. They do this by a number of different mechanisms including the approximation of the reactants, nucleophilic/electrophilic catalysis and acid/base catalysis. These mechanisms will be explained below.
== Outpatient and home care == Today, chemotherapy is frequently given in outpatient clinics or taken at home as pills rather than during long hospital stays. It allows patients to recover in a more comfortable environment. Because of how the human body processes these medications, home care introduces unique safety needs. Chemotherapy drugs leave the patient’s system through body fluids like urine, stool, vomit, sweat, and saliva mostly during the first 24 hours to 7 days after treatment. Because these trace toxic chemicals can accidentally expose healthy family members through touch, shared surfaces or as aerosolized droplets during waste disposal, public health groups recommend basic safety habits at home. These typically include washing the patient's laundry separately, double-flushing toilets with the lid down, and having caregivers wear disposable gloves when handling body fluids. Epidemiological guidelines similarly address residential sexual intimacy and recommend basic safety habits to prevent healthy partners from absorbing the medicine, noting that because teratogenic trace elements are shed via saliva, semen, vaginal secretions and other body fluids, oncologists mandate the temporary use of barrier contraceptives and avoiding deep kissing during the drug-clearance window to prevent healthy partner exposure and avoid potential fetal complications. Consequently, family members are advised to avoid close contact or kissing if they show any signs of illness, such as a cold or cold sore, to keep the patient safe from secondary infections.
Chemical synthesis, either from petrochemical starting materials or from natural products extracts. Biotechnology, specifically biocatalysis (enzymatic methods) and biosynthesis (fermentation) for small molecules, and cell culture technology for big molecules. Extraction from animals, microorganisms, or plants; for example, isolation and purification is used for alkaloids, antibacterials (especially penicillins), and steroids. Hydrolysis of proteins, especially when combined with ion exchange chromatography, used, for instance, for amino acids. Chemical synthesis and biotechnology are most frequently used, sometimes in combination.
The placula hypothesis, proposed by Otto Bütschli, holds that the last common ancestor of animals was an amorphous blob with no symmetry or axis. The center of this blob rose slightly above the silt, forming a hollow that aided feeding on the sea floor underneath. As the cavity grew deeper and deeper, the organisms resembled a thimble, with an inside and an outside. This body shape is found in sponges and cnidaria. This explanation leads to the formation of the bilaterian body plan; the urbilaterian would develop its symmetry when one end of the placula became adapted for forward movement, resulting in left-right symmetry. The planula hypothesis, proposed by Bütschli, suggests that metazoa are derived from planula; that is, the larva of certain cnidaria, or the adult form of the placozoans. Under this hypothesis, the larva became sexually mature through paedomorphosis, and could reproduce without passing through a sessile phase. The gastraea hypothesis was proposed by Ernst Haeckel in 1874, shortly after his work on the calcareous sponges. He proposed that this group of sponges is monophyletic with all eumetazoans, including the bilaterians. This suggests that the gastrulation and the gastrula stage are universal for eumetazoans. It has been perceived as problematic that gastrulation by invagination is by no means universal among eumetazoans. Only recently has an invagination been confirmed in a Calcarea sponge, albeit too early to form a remaining inner space (archenteron).
=== C1q chains A, B and C === C1q is composed of 18 polypeptide chains: six A-chains, six B-chains, and six C-chains. Each chain contains a collagen-like region located near the N terminus and a C-terminal globular region. The A-, B-, and C-chains are arranged in the order A-C-B on chromosome 1.
Sources: en.wikipedia.org
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.
Tuftsin contains four residues, while selank carries an additional Pro-Gly-Pro segment at the carboxyl end. That extension is intended to reduce enzymatic cleavage. Comparative pharmacokinetic data in humans remain limited.
No single receptor target is widely accepted as the definitive mediator of the reported effects. Proposed contributors include GABAergic modulation, shifts in monoamine turnover, and altered neuropeptide degradation. The mechanism is treated in the literature as unresolved.
Purity is usually reported as an HPLC area percentage, most often measured at 214 nm. Identity is confirmed separately by mass spectrometry. A certificate of analysis should state both the method and the observed value.