Everything below concerns Pro-Gly-Pro. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-03-02. Numbers and descriptions here follow the published literature rather than marketing material.
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analog of the tetrapeptide tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Reported consistently across pharmacopoeial descriptions |
| Appearance | White to off-white lyophilized powder | Typical form of research-grade material |
| Solubility | Freely soluble in water | Aqueous buffers; poor in nonpolar solvents |
| Typical storage temperature | -20 degrees Celsius | Lyophilized powder; protect from moisture |
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.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Laboratory work relies on standard behavioral paradigms. Rodents are tested in the elevated plus maze, open field, and passive avoidance tasks, with outcomes compared against diazepam or vehicle controls. Intranasal dosing is used most often because it bypasses first-pass metabolism, though intraperitoneal and intravenous routes also appear in published protocols. Biochemical endpoints include tissue BDNF concentrations, cytokine levels, and monoamine metabolites. Human data are limited to small Russian trials reporting reduced anxiety scores; most were not prospectively registered, and few employed independent outcome assessment.
Measuring peptide exposure inside the brain is technically difficult. Selank is degraded rapidly in plasma, and assays must separate intact peptide from fragments, which favors targeted mass spectrometry over immunoassays alone. Reported half-lives are short, on the order of minutes, so effects observed hours later are attributed to downstream signaling rather than to the parent compound. Blood-brain barrier permeability is debated and rarely quantified directly. Gaps include absent dose-response characterization, inconsistent reporting of purity, and almost no pharmacokinetic data from human participants.
Selank is studied chiefly as an animal-model anxiolytic with proposed secondary effects on memory and immune signaling. Reported mechanisms include modulation of the GABA-A receptor complex, inhibition of enkephalin-degrading enzymes, and shifts in monoamine turnover within limbic structures. Some experiments describe increased expression of brain-derived neurotrophic factor in the hippocampus after repeated dosing. No single molecular target has been confirmed, and the peptide does not bind any receptor with the selectivity typical of a conventional small-molecule drug. Mechanism therefore remains a set of hypotheses rather than an established pathway.
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.
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
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.
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.
In the US, the additive is not for direct consumer sale. Lean finely textured beef can constitute up to 15% of ground beef without additional labeling, and it can be added to other meat products such as beef-based processed meats. USDA disallows the use of spinal cord, organ meat such as cow intestines, bones, and connective tissue such as tendons in LFTB. USDA requires the trimmings used to make LFTB to meet the same microbiological standards as other beef. Because of ammonium hydroxide use in its processing, the lean finely textured beef by BPI is not permitted in Canada. Health Canada stated that: "Ammonia is not permitted in Canada to be used in ground beef or meats during their production" and may not be imported, as the Canadian Food and Drugs Act requires that imported meat products meet the same standards and requirements as domestic meat. Canada does allow Cargill's citric acid-produced Finely Textured Meat (FTM) to be "used in the preparation of ground meat" and "identified as ground meat" under certain conditions. Production of mechanically separated meat via use of bones or bone-in cuts of bovine, ovine and caprine animals are prohibited in the European Union.
=== Antithrombotics === Aspirin, an antiplatelet drug, is given as a loading dose to reduce the clot size and reduce further clotting in the affected artery. It is known to decrease mortality associated with acute myocardial infarction by at least 50%. P2Y12 inhibitors such as clopidogrel, prasugrel and ticagrelor are given concurrently, also as a loading dose, with the dose depending on whether further surgical management or fibrinolysis is planned. Prasugrel and ticagrelor are recommended in European and American guidelines, as they are active more quickly and consistently than clopidogrel. P2Y12 inhibitors are recommended in both NSTEMI and STEMI, including in PCI, with evidence also to suggest improved mortality. Heparins, particularly in the unfractionated form, act at several points in the clotting cascade, help to prevent the enlargement of a clot, and are also given in myocardial infarction, owing to evidence suggesting improved mortality rates. In very high-risk scenarios, inhibitors of the platelet glycoprotein αIIbβ3a receptor such as eptifibatide or tirofiban may be used. There is varying evidence on the mortality benefits in NSTEMI. A 2014 review of P2Y12 inhibitors such as clopidogrel found they do not change the risk of death when given to people with a suspected NSTEMI prior to PCI, nor do heparins change the risk of death. They do decrease the risk of having a further myocardial infarction.
In 2003, following the Soccer Australia team's failure to qualify for the 2002 FIFA World Cup, allegations of fraud and mismanagement were levelled at Soccer Australia by elements within the Australian press including the ABC. Soccer Australia commissioned an independent inquiry known as the Crawford Report as a result of the Australian government's threat to withdraw funding to the sport. Any political interference would have constituted a breach of FIFA statutes. The findings of the report were critically analysed by the board of Soccer Australia who believed that the recommendations contained therein were not capable of being implemented. The report recommended, among other things, the reconstitution of the organisation with an interim board headed by prominent businessman Frank Lowy. Some three months after Lowy's appointment, Soccer Australia was placed into liquidation and the Australian Soccer Association (ASA) was created and seized control of the premier soccer competitions and teams without encompassing the Crawford Report recommendations and effectively disenfranchised all other organisations and parties with an interest in Soccer Australia. The Australian government provided approximately $15 million to the ASA. On 1 January 2005, ASA renamed itself Football Federation Australia (FFA), aligning with the international usage of the name "football" in preference to "soccer" and, by a more distinct name, distancing itself from the failings of the former Soccer Australia. It coined the phrase "old soccer, new football" to emphasise this.
Paracetamol, or acetaminophen, is an analgesic and antipyretic agent used to treat fever and mild to moderate pain. It is a widely available over-the-counter drug sold generically or under various brand names, including Tylenol and Panadol. Paracetamol relieves pain in acute mild migraine and episodic tension headaches. At a standard dose, paracetamol slightly reduces fever, though it is inferior to ibuprofen in that respect: the benefits of its use for fever are unclear, particularly in the context of fever of viral origins. Paracetamol is effective for pain after wisdom tooth extraction, but it is less effective than ibuprofen. The combination of paracetamol and ibuprofen provides greater analgesic efficacy than either drug alone. The pain relief paracetamol provides in osteoarthritis is small and clinically insignificant. Evidence supporting its use in low back pain, cancer pain, and neuropathic pain is insufficient. Paracetamol is the first-line treatment for pain and fever in pregnancy; no causal association with neurodevelopmental disorders has been established, while untreated pain and fever can harm the mother and fetus. At a recommended maximum daily dose for an adult of three to four grams, paracetamol is safe and effective in the short term when used as directed, with uncommon adverse effects similar to those of ibuprofen. It is often used in patients who cannot tolerate nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen.
He also stated that "Nations should not be punished in place of terrorists." According to Radio Farda's website, when the news of the attacks was released, some Iranian citizens gathered in front of the Embassy of Switzerland in Tehran, which serves as the protecting power of the United States in Iran, to express their sympathy, and some of them lit candles as a symbol of mourning. Radio Farda's website also states that in 2011, on the anniversary of the attacks, the United States Department of State published a post on its blog, in which the Department thanked the Iranian people for their sympathy and stated that it would never forget Iranian people's kindness. After the attacks, both the President and the Supreme Leader of Iran condemned the attacks. The BBC and Time magazine published reports on holding candlelit vigils for the victims by Iranian citizens on their websites. According to Politico Magazine, following the attacks, Ali Khamenei, the Supreme Leader of Iran, "suspended the usual 'Death to America' chants at Friday prayers" temporarily.
Sources: en.wikipedia.org
Teva and Sandoz are by far the largest generics companies. They differ from their competitors not only in sales revenues but also because they are backwards integrated and have proprietary drugs in their portfolios. They also vie for the biosimilars market. Several thousand small or virtual pharma companies focus on R&D of just a few lead compounds. They typically originate mostly from academia. Therefore, their R&D strategy is more focused on the elucidation of the biological roots of diseases rather than developing synthesis methods.
UIUC Histology Subject 777 Illustration at wku.edu Anatomy photo: Musculoskeletal/muscle/skeletal1/skeletal3 - Comparative Organology at University of California, Davis MedEd at Loyola histo/practical/muscle/hp7-42.html
Hendrickx commented that both S. lingyuanensis and Huadanosaurus can alternatively be suggested as juveniles of already known tyrannosauroids from the Jehol Biota, since the describers did not provide strong arguments against this possibility.
the argyrophilic (silver staining) fibrous structures present in basement membranes histologically similar fibers present in developing connective tissue. The history of the reticulin silver stain is reviewed by Puchtler et al. (1978). The abstract of this paper says:
=== Differential diagnosis === Given the variety and nonspecific nature of symptoms that can be associated with autoimmune diseases, differential diagnosis—determining which of several diseases with similar symptoms is causing a patient's illness—is an important part of the diagnostic process. This often involves ruling out other potential causes of symptoms, such as infections, malignancies, or genetic disorders.
Sources: en.wikipedia.org
==== Effect on differentiation ==== ECM elasticity can direct cellular differentiation, the process by which a cell changes from one cell type to another. In particular, naive mesenchymal stem cells (MSCs) have been shown to specify lineage and commit to phenotypes with extreme sensitivity to tissue-level elasticity. MSCs placed on soft matrices that mimic the brain differentiate into neuron-like cells, showing similar shape, RNAi profiles, cytoskeletal markers, and transcription factor levels. Similarly stiffer matrices that mimic muscle are myogenic, and matrices with stiffnesses that mimic collagenous bone are osteogenic.
In addition to the base stations, the Index's headset and controllers feature Inertial Measurement Units (IMUs) that provide rapid updates on movement and orientation. The IMUs track motion at several hundred Hz, but are prone to drift. The Lighthouse system compensates for this drift by using the base stations’ lasers to provide a precise positional reference, integrating this data with the IMU information to maintain accurate tracking even during fast movements. This combination of external base stations and internal sensors on the tracked devices ensures the Valve Index provides accurate and responsive tracking performance.
In 1838, France enacted a law to regulate both the admissions into asylums and asylum services across the country. In the United States, the erection of state asylums began with the first law for the creation of one in New York, passed in 1842. The Utica State Hospital was opened around 1850. Many state hospitals in the United States were built in the 1850s and 1860s on the Kirkbride Plan, an architectural style meant to have curative effect. At the turn of the century, England and France combined had only a few hundred individuals in asylums. By the late 1890s and early 1900s, this number had risen to the hundreds of thousands. However, the idea that mental illness could be ameliorated through institutionalization ran into difficulties. Psychiatrists were pressured by an ever-increasing patient population, and asylums again became almost indistinguishable from custodial institutions. In the early 1800s, psychiatry made advances in the diagnosis of mental illness by broadening the category of mental disease to include mood disorders, in addition to disease level delusion or irrationality. The 20th century introduced a new psychiatry into the world, with different perspectives of looking at mental disorders. For Emil Kraepelin, the initial ideas behind biological psychiatry, stating that the different mental disorders are all biological in nature, evolved into a new concept of "nerves", and psychiatry became a rough approximation of neurology and neuropsychiatry.
=== Cuban Communist Party and government === Initially, First Secretary of the Cuban Communist Party Miguel Díaz-Canel condemned "U.S. imperialism", and called on people to prepare for a "war of the entire nation", while organizing state-sponsored demonstrations against the American oil blockade. On 6 February, he declared that "Cuba is ready for a talk with Washington on every topic without prerequisites", while rejecting negotiations on cases that he viewed as "internal Cuban affairs".
Sources: en.wikipedia.org
Selank is a synthetic seven-amino-acid peptide modeled on tuftsin, a fragment of the immunoglobulin G heavy chain. It was designed in Russia to combine anxiolytic and immunomodulatory properties in one molecule.
The first four residues of Selank reproduce the tuftsin sequence Thr-Lys-Pro-Arg. A Pro-Gly-Pro extension at the C-terminus was added to slow enzymatic breakdown and extend residence time.
It holds marketing authorization in Russia, where nasal drop formulations are sold. No equivalent approval exists in the European Union, the United States, or most other countries.
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.