Everything below concerns certificate of analysis. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Principal proposed target | GABA-A receptor complex | Hypothesis derived mainly from animal pharmacology |
| Common behavioral assay | Elevated plus maze | Rodent test for anxiety-like behavior |
| Reported molecular marker | Hippocampal BDNF expression | Measured by immunoassay or mRNA quantification |
| Typical dosing route | Intranasal | Chosen to reduce first-pass metabolism |
| Reported plasma half-life | Minutes | Based on limited peptide stability data |
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.
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.
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.
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.
== Grand Mufti of Saudi Arabia == On 22 October 2025, under recommendation by Crown Prince Muhammad bin Salman, King Salman appointed al-Fawzan as Grand Mufti of Saudi Arabia, succeeding Abdulaziz Al al-Sheikh.
== Applications == LSF has been demonstrated in an alkaloid toxin (veratridine) and used to introduce an azobenzene group to control the toxin activity with light. The two reported LSF routes may allow introducing other functional groups like radioactive or fluorescent labels.
In effect, the Spanish Constitution of 1812 adopted by the Cortes of Cádiz served as the basis for independence in New Spain and Central America, since in both regions it was a coalition of conservative and liberal royalist leaders who led the establishment of new states. The Spanish Constitution of 1812 attempted to return to the policies that the Spanish government had implemented under Habsburg rule. These policies gave recognized Spanish colonial territory as fellow kingdoms with equal standing to Spain. The policies under the Habsburgs, moreover, allowed for constant revisionism, through corruption and the sale of office, that provided the opportunity to grant more rights and change policy to respond to the demands of the populations. The restoration of the Spanish Constitution and representative government was enthusiastically welcomed in New Spain and Central America. Elections were held, local governments formed and deputies sent to the Cortes. The Spanish Constitution of 1812 could have been an opportunity to enact social change slowly and without the threat of a radicalized uprising from the lower social classes by offering an opportunity to enact change that those in power would believe would best benefit their respective territories. Among liberals, however, there was fear that the new regime would not last; and conservatives and the Church worried that the new liberal government would expand its reforms and anti-clerical legislation.
Sources: en.wikipedia.org
==== Biofilm management ==== We are developing greater insight into the association between delayed healing and the presence of biofilm. The relationship between delayed healing and the need for debridement is also being acknowledged. It has been suggested that the presence of wound slough provides an indication of biofilm presence, therefore, indicating the need to reduce the wound bioburden. Methods of effectively managing wound biofilms have been reported and include the use of topical agents, systemic antibiotics and regular episodes of debridement. Despite these advances it has been recognised that indiscriminate and widespread use of antibiotics both inside and outside of medicine is playing a substantial role in the emergence of bacterial resistance. On a more positive note, antiseptics have been reported to possess a clear cut role in the control of wound bioburden where there are indications or risk of infection.
=== Slovak === Traditionally, the word najneobhospodarovávateľnejšieho ("of the least cultivable", 31 letters) is considered as the longest Slovak word, but there are some longer artificial words. Most of them are compound adjectives in dative, instrumental or other grammatical case and derived from the iterative or frequentative verbal form or the ability adjective form (like -able).
Even greater inconsistency and confusion is associated with various "Non-GMO" or "GMO-free" labeling schemes in food marketing, where even products such as water or salt, which do not contain any organic substances and genetic material (and thus cannot be genetically modified by definition), are being labeled to create an impression of being "more healthy".
The prothrombin time (PT) – along with its derived measures of prothrombin ratio (PR) and international normalized ratio (INR) – is an assay for evaluating the extrinsic pathway and common pathway of coagulation. This blood test is also called protime INR and PT/INR. They are used to determine the clotting tendency of blood, in conditions such as the measure of warfarin dosage, liver damage (cirrhosis), and vitamin K status. PT measures the following coagulation factors: I (fibrinogen), II (prothrombin), V (proaccelerin), VII (proconvertin), and X (Stuart–Prower factor). PT is often used in conjunction with the activated partial thromboplastin time (aPTT) which measures the intrinsic pathway and common pathway of coagulation.
Sources: en.wikipedia.org
Intranasal administration predominates in both animal and human research because it avoids hepatic first-pass metabolism. Injectable and intraperitoneal routes appear in animal work mainly for comparison.
Behavioral endpoints include time spent in open arms of the elevated plus maze and avoidance latencies. Biochemical endpoints include BDNF concentration, cytokine levels, and monoamine metabolite ratios in brain tissue.
Most published studies are small, originate from a limited number of laboratories, and lack independent replication. Dose-response relationships, measured brain exposure, and long-term outcomes are not well characterized.
Reports describe modulation of GABA signalling, changes in monoamine turnover and effects on neurotrophic factor expression. These observations come mainly from animal and cell studies. A single unifying mechanism has not been demonstrated.