A practical reference on BDNF: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-04-11 and is reviewed periodically as new material appears.
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 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.
| Property | Value | Notes |
|---|---|---|
| Typical purity report | 95% or higher by HPLC | Area percentage at 214 nm |
| Identity confirmation | Mass spectrometry | Electrospray or MALDI |
| Powder storage | -20 C, desiccated | Protect from light |
| Solution storage | 2-8 C short term | Freeze aliquots for longer |
| Quality document | Certificate of analysis | States method and value |
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.
Peptide bonds are vulnerable to protease attack, and Selank is no exception. Measured half-life in serum is short, on the order of minutes in several reports, which explains why intranasal administration is the common route described in the literature. Absorption across the nasal mucosa partially bypasses first-pass hepatic metabolism. Quantitative data on human bioavailability remain limited and are difficult to compare across studies.
Lyophilised material kept dry at minus 20 degrees Celsius or colder is the most stable form, and suppliers commonly state a shelf life of two years or more under those conditions. Once dissolved, degradation accelerates through hydrolysis and deamidation, particularly at alkaline pH or elevated temperature. Working solutions are usually divided into single-use aliquots to avoid repeated freeze-thaw cycles. The choice of reconstitution solvent affects both stability and the ionic strength of the final preparation.
Reverse-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres is the standard purity method. Mass spectrometry, typically electrospray ionisation, confirms identity through the expected mass-to-charge pattern. Amino acid analysis can verify composition independently. Chiral purity requires separate techniques such as derivatisation followed by chromatographic separation, and such data are rarely reported for research-grade material.
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.
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.
==== PC reception ==== Upon its retail release, Counter-Strike received highly favorable reviews. The New York Times reported that E-Sports Entertainment ESEA League started the first professional fantasy e-sports league in 2004 with the game Counter-Strike. Some credit the move into professional competitive team play with prizes as a major factor in Counter-Strike's longevity and success. The game was praised by critics for its emphasis on teamwork and communication among players. Scott Osborne, writing for GameSpot, felt that the audio messages were a decent feature, which covered requests for backup, status reports and warnings. One problem, according to him, was that both teams used the same voice. Clayton Wolfe of IGN expressed the importance of teamwork and stating, "It's the team-based tactics that make [Counter-Strike] so fun." Computer Games Magazine's Bill Hiles also commented about the social aspects of the game, saying that a player should work in teams rather than alone. Joe Dodson for GameRevolution wrote that "Nothing can beat a coordinated, experienced team in [Counter-Strike], except an even more coordinated and experienced team." He also found the team talk favorable. Most reviewers agreed that the GoldSrc engine felt dated, but still praised the graphics. Hiles commented that the visuals were acceptable and "do an admirable job portraying outdoor locations", while Dodson noted the graphics were identical to Half-Life.
=== 1099 reporting === A payor must report payments for goods or services via payment apps, online marketplaces, and payments from credit, debit, or gift cards to the Internal Revenue Service and the payee on Form 1099-K. The law changes the threshold for reporting; now reporting on Form 1099-K is required if a person received at least 200 transactions and received at least $20,000. The law increases the reporting threshold for Form 1099-MISC and Form 1099-NEC from $600 to $2,000 in 2026. The threshold will be adjusted for inflation for future years.
In September 2022, NewsGuard Technologies reported that among the TikTok searches it had conducted and analyzed from the US, 19.4% surfaced misinformation such as questionable or harmful content about COVID-19 vaccines, homemade remedies, the 2020 US elections, the Russian invasion of Ukraine, the Robb Elementary School shooting, and abortion. NewsGuard suggested that in contrast, results from Google were of higher quality. Mashable's own test from Australia found innocuous results after searching for "getting my COVID vaccine" but suggestions such as "climate change is a myth" after typing in "climate change". In November 2023, Singaporean Law and Home Affairs Minister K. Shanmugam applied for court orders requiring TikTok to provide information on the identity of three users that he accuses of spreading false and defamatory information about him. The users had shared on TikTok an article published by celebscritic.com alleging that K. Shanmugam was involved in an extra-marital affair. According to an investigation published in September 2025 by Moldovan newspaper Ziarul de Gardă, before the 2025 Moldovan parliamentary election, hundreds of accounts with false identities were created to spread Russian propaganda in TikTok and Facebook. That month, Bloomberg reported, citing European officials and documents of undisclosed origin, that Russia had prepared a plan to interfere in the election, which would have included a disinformation campaign in both Romanian and Russian on Facebook, Telegram and TikTok.
Sources: en.wikipedia.org
== Pathology == It has been suggested that these cell rests are the histogenetic origins of Brenner tumors, due to the histological similarity of the epithelium of Walthard cell rests and Brenner tumors to the urothelium of the lower urinary tract. Also, it has been proposed that Brenner tumors and Walthard cell rests signify urothelial differentiation within the female genital tract.
(The Ruthenian part, Subcarpathian Rus, made also an attempt to declare its sovereignty as Carpatho-Ukraine but only with ephemeral success since the area was soon annexed by Hungary.) Although "Henlein and the SdP had become accessories in Hitler's escalating campaign to annex the Sudetenland to the German Reich" by the summer of 1938, the supporters of the SdP supported autonomy within Czechoslovakia rather than annexation into Germany. Contemporary reports of The Times found that there was a "large number of Sudetenlanders who actively opposed annexation", and that the pro-German policy was challenged by the moderates within the SdP as well; according to Wickham Steed, over 50% of Henlein's supporters favoured greater autonomy within Czechoslovakia rather than joining Germany. Sudeten German historian Emil Franzel argues that the mainstream wing of Henlein's party was "not striving for annexation to Germany, but for genuine autonomy", and the majority of negotiators who conducted talks with Hodža and Beneš belonged to the pro-autonomy wing and were unaware of Henlein's agreements with Hitler. Part of the borderland had an ethnic Polish majority and was invaded and annexed by Poland in 1938.
In the 13th and 14th centuries, some pilgrims to Canterbury journeyed via Billericay. Some of them may have spent the night in the town before crossing the river Thames at Tilbury; this may account for the large number of inns. The town's most notable historical episode was the Battle of Billericay during the Peasants' Revolt of 1381.
Alfred Guillou Redfield (March 11, 1929 – July 24, 2019) was an American physicist and biochemist. In 1955 he published the Redfield relaxation theory, effectively moving the practice of NMR or Nuclear magnetic resonance from the realm of classical physics to the realm of semiclassical physics. He is known for the development of Redfield equation. He continued to find novel magnetic resonance applications to solve real-world problems throughout his life. Redfield earned degrees at Harvard College (BA 1950, Master's 1952) and the University of Illinois, Urbana-Champaign (Ph.D. 1953). As a postdoc, he worked with Nicolaas Bloembergen at Harvard, where he first published the Redfield relaxation theory. IBM Watson Scientific Computing Laboratory hired him in 1955 and he taught at Columbia. While there, he published his most important work, the Redfield Relaxation Equation. In 1971 he published experiments that helped to draw the veil of H₂O molecules away from hitherto invisible atoms in large, biological molecules. He continued to innovate specific NMR techniques to view the molecular structure of nucleic acids and enzymes. Beginning in 1996, the NMR Field Cycling community began to realize that slow NMR had an advantage over X-ray crystallography for observing large, biological molecule (macromolecule) dynamics, which can't be captured by high-energy NMR or crystallography. In 1996 he released an article exploring field cycling as a way to study macromolecules in more detail. He published his first article using the phosphorus isotope 31P to probe phospholipids in 2004.
Sources: en.wikipedia.org
WebElements – Selenium NIH – Selenium Fact Sheet for Consumers Assay – Supra-Regional Assay Service ATSDR – Toxicological Profile for Selenium Elementymology & Elements Multidict – Selenium page by Peter van der Krogt
Nausea and vomiting are two of the most feared cancer treatment-related side-effects for people with cancer and their families. In 1983, Coates et al. found that people receiving chemotherapy ranked nausea and vomiting as the first and second most severe side-effects, respectively. Up to 20% of people receiving highly emetogenic agents in this era postponed, or even refused potentially curative treatments. Chemotherapy-induced nausea and vomiting (CINV) are common with many treatments and some forms of cancer. Since the 1990s, several novel classes of antiemetics have been developed and commercialized, becoming a nearly universal standard in chemotherapy regimens, and helping to successfully manage these symptoms in many people. Effective mediation of these unpleasant and sometimes debilitating symptoms results in increased quality of life for the recipient and more efficient treatment cycles, as patients are less likely to avoid or refuse treatment.
=== Pressure reduction === Pressure must be removed from high risk body areas by frequent changes in position in bed or chair, including turning side to side. Chair cushions and air mattresses should be used for immobile patients. Heels should be off of the bed.
=== Caucus memberships === Sanders was only the third senator from Vermont to caucus with the Democrats, after Jeffords and Leahy. His caucusing with the Democrats gave them a 51–49 majority in the Senate during the 110th Congress in 2007–08. The Democrats needed 51 seats to control the Senate because Vice President Dick Cheney would likely have broken potential ties in favor of the Republicans. He is a member of the following caucuses:
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.
Sources: en.wikipedia.org
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.
Dry powder is kept frozen, desiccated, and shielded from light. Dissolved material is aliquoted and frozen to limit freeze-thaw cycles. Short-term refrigerated storage is common for working solutions.
Russia registers it as a prescription nasal product. Most other markets classify it as a research chemical with no approved medical use. Oversight of purity and labeling is consequently minimal in those markets.
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.