BDNF raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-05-19 and is reviewed periodically as new material appears.
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.
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.
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.
| 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 |
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.
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.
== Properties == Films of PPy are yellow but darken in the air due to some oxidation. Doped films are blue or black depending on the degree of polymerization and film thickness. They are amorphous, showing only weak diffraction. PPy is described as "quasi-unidimensional" vs one-dimensional since there is some crosslinking and chain hopping. Undoped and doped films are insoluble in solvents but swellable. Doping makes the materials brittle. They are stable in the air up to 150 °C at which temperature the dopant starts to evolve (e.g., as HCl). Doping the polymer requires that the material swell to accommodate the charge-compensating anions. The physical changes associated with this charging and discharging have been discussed as a form of artificial muscle. The surface of polypyrrole films present fractal properties and ionic diffusion through them show anomalous diffusion pattern.
In construction engineering, in situ construction refers to building work carried out directly on-site using raw materials, as opposed to prefabrication, where components are manufactured off-site and assembled on-site. In situ concrete is poured at its final location, offering structural stability compared to precast construction. In wall construction, reinforcing bars are assembled first, followed by the installation of formwork to contain the poured concrete. Once the concrete has cured, the formwork is removed, leaving the wall in place. Prefabrication, in contrast, reduces on-site labor requirements and shortens project timelines, but requires precise pre-planning and involves higher manufacturing and transportation costs. In geotechnical engineering, the term in situ describes soil in its natural, undisturbed state, as opposed to fill material, which has been excavated and relocated. The differences between undisturbed soil and fill material affect how well a site can support structures, install underground utilities, and manage water drainage. Proper assessment of soil conditions is necessary to prevent issues such as uneven settling, unstable foundations, and poor water infiltration.
=== Amateur career === Casey made her amateur debut in 2012, losing a split decision to future UFC Strawweight Emily Kagan. Casey then went on a four fight win streak, earning three wins by armbar and capturing the Tuff-N-Uff Flyweight title in the process and defending it once.
Activation of presynaptic dopamine autoreceptors by dihydroergocriptine leads to reduced dopamine receptor turnover and indirect antioxidant effects. In particular, further activation of intracellular kinase systems due to dopamine agonists are hypothesized to lead to antiapoptotic effects that also help in halting and slowing the disease progression. This may also contribute to prevention of development of motor fluctuations, though more research is needed. Modern agonists like dihydroergocryptine typically cost two to three times more than levodopa therapy. More health economics assessments may be needed to determine whether the initial increased costs of the agonists are offset by less patients needing surgery in later stages of the disease.
Sources: en.wikipedia.org
Users have reported that mephedrone causes euphoria, stimulation, an enhanced appreciation for music, an elevated mood, decreased hostility, improved mental function and mild sexual stimulation; these effects are similar to the effects of cocaine, amphetamines and MDMA, and last different lengths of time depending on the way the drug is taken. Of 70 Dutch users of mephedrone, 58 described it as an overall pleasant experience, and 12 described it as an unpleasant experience. In a survey of UK users who had previously taken cocaine, most users found it produced a better-quality and longer-lasting high and was less addictive. The users were also asked to compare the "risk", and they answered that it was equal. A study of users in Northern Ireland found they did not equate the fact that mephedrone was legal with it being safe to use. This was contrary to another study in New Zealand, where users of benzylpiperazine thought that because it was legal, it was safe.
Activity-based proteomics, or activity-based protein profiling (ABPP) is a chemoproteomic strategy that employs modular probes to directly assess the functional state of enzymes within complex proteomes. Unlike expression-based proteomics, which measures protein abundance, ABPP provides information about catalytic activity, thereby enabling researchers to distinguish between active and inactive forms of enzymes. This functional perspective has proven valuable for identifying drug targets, mapping ligandable sites, and understanding enzyme regulation in physiological and pathological contexts. By covalently modifying active sites, activity-based probes (ABPs) allow selective tagging, enrichment, and isolation of proteins, reducing the complexity of proteomic samples and facilitating downstream analysis. ABPP has been applied across diverse biological systems, including cells, tissues, and whole organisms, and has contributed to advances in biomarker discovery, drug development, and in vivo imaging.
Infant formulas made with soy protein phytoestrogens are considered safe alternatives to formulas containing dairy ingredients, which may be excluded for infants with galactosemia and hereditary lactose intolerance. Some reviews express the opinion that more research is needed to answer the question of what effect phytoestrogens may have on infants, but their authors did not find any adverse effects. Studies conclude there are no adverse effects in human growth, development, or reproduction as a result of the consumption of soy-based infant formula compared to conventional cow-milk formula. The American Academy of Pediatrics states: "although isolated soy protein-based formulas may be used to provide nutrition for normal growth and development, there are few indications for their use in place of cow milk-based formula. These indications include (a) for infants with galactosemia and hereditary lactase deficiency (rare) and (b) in situations in which a vegetarian diet is preferred."
== Bibliography == Audi, G.; Kondev, F. G.; Wang, M.; et al. (2017). "The NUBASE2016 evaluation of nuclear properties". Chinese Physics C. 41 (3) 030001. Bibcode:2017ChPhC..41c0001A. doi:10.1088/1674-1137/41/3/030001. Beiser, A. (2003). Concepts of modern physics (6th ed.). McGraw-Hill. ISBN 978-0-07-244848-1. OCLC 48965418. Hoffman, D. C.; Ghiorso, A.; Seaborg, G. T. (2000). The Transuranium People: The Inside Story. World Scientific. ISBN 978-1-78-326244-1. Kragh, H. (2018). From Transuranic to Superheavy Elements: A Story of Dispute and Creation. Springer. ISBN 978-3-319-75813-8. Zagrebaev, V.; Karpov, A.; Greiner, W. (2013). "Future of superheavy element research: Which nuclei could be synthesized within the next few years?". Journal of Physics: Conference Series. 420 (1) 012001. arXiv:1207.5700. Bibcode:2013JPhCS.420a2001Z. doi:10.1088/1742-6596/420/1/012001. ISSN 1742-6588. S2CID 55434734.
=== Phase 2 === AD-036 – undefined mechanism of action [6] Atomoxetine/mineralocorticoid receptor antagonist (atomoxetine/antimineralocorticoid; AD-113) – combination of atomoxetine (norepinephrine reuptake inhibitor) and a mineralocorticoid receptor antagonist [7] Atomoxetine/trazodone (trazodone/atomoxetine; AD-504) – combination of atomoxetine (norepinephrine reuptake inhibitor) and trazodone (various actions/hypnotic) [8] BAY-2586116 – potassium channel blocker [9] CX-1739 – ampakine (AMPA receptor positive allosteric modulator) [10] Dronabinol low-dose (tetrahydrocannabinol; THC; PP-001) – cannabinoid CB1 and CB2 receptor agonist [11] Dronabinol/palmidrol (SCI-110; THX-OSA01; THX-RS01; THX-110; THX-TS01; THC/PEA) – combination of dronabinol (THC; cannabinoid receptor agonist) and palmidrol (palmitoylethanolamine (PEA); various actions) [12] Lorundrostat (MLS-101; MT-4129) – aldosterone synthase (CYP11B2) inhibitor [13] Phentermine/topiramate (Qnexa; Qsiva; Qsymia; topiramate/phentermine; VI-0521) – combination of phentermine (norepinephrine releasing agent) and topiramate (various actions) [14] Research programme: Sleep disordered breathing therapeutics - Shinogi-Apnimed Sleep Science – undefined mechanisms of action [15] SASS-001 – purinergic P2X3 receptor antagonist [16] Sivopixant (S-600918) – purinergic P2X3 receptor antagonist [17] Sulthiame (SASS-002; sulthiame; Sultia; sultiame) – carbonic anhydrase inhibitor [18] [19] Trazodone/viloxazine (AD-816; viloxazine/trazodone) – combination of trazodone (various actions/hypnotic) and viloxazine (norepinephrine reuptake inhibitor) [20]
Sources: en.wikipedia.org
== External links == Kavkaz-2008 leaflet ("Soldier, know your probable enemy"), The Guns of August 2008: Russia's War in Georgia, p. xi - xii Anna Nemtsova, Q&A: Georgia's Mikheil Saakashvili on Russia Fight, Newsweek, 11 August 2008 William Rees-Mogg, Georgia: another Sarajevo moment avoided, The Times, 11 August 2008 Illarionov: Russia Lost the Georgian War, The Other Russia, 13 August 2008 (in Russian) "We Will never surrender", Der Spiegel, 18 August 2008 (in Russian) Vadim Rechakolv's comment on the movement of Russian tank column through the Roki Tunnel on 7 August Denis Macshane, Denis MacShane Explores the Myths About Russia, Newsweek, 5 September 2008 Ministry of Foreign Affairs of Georgia, Media and telephone intercepts confirm Russia started the war, 20 September 2008 (in Russian) André Glucksmann, Putin's doctrine, 22 October 2008 The Government of Georgia, Factual Evidence Contradicts War Claims in Recent Media Stories;, 18 November 2008 Bear on the Prowl? The Return of Russia as a Great Power Archived 17 March 2024 at the Wayback Machine; Australian Institute of International Affairs, November 2008 Julia Latynina - Articles on August war (Translations) Report by the Government of Georgia on the aggression by the Russian Federation against Georgia, 7 August 2009. PDF file. (in Russian) Grani TV, Andrei Nekrasov, Movie director, Garry Kasparov about "Russian Lessons", 14 September 2009 Caucasus Analytical Digest No.
The manual differential can identify cell types that are not counted by automated methods and detect clinically significant changes in the appearance of white blood cells. In 1674, Antonie van Leeuwenhoek published the first microscopic observations of blood cells. Improvements in microscope technology throughout the 18th and 19th centuries allowed the three cellular components of blood to be identified and counted. In the 1870s, Paul Ehrlich invented a staining technique that could differentiate between each type of white blood cell. Dmitri Leonidovich Romanowsky later modified Ehrlich's stain to produce a wider range of colours, creating the Romanowsky stain, which is still used to stain blood smears for manual differentials. Automation of the white blood cell differential began with the invention of the Coulter counter, the first automated hematology analyzer, in the early 1950s. This machine used electrical impedance measurements to count cells and determine their sizes, allowing white and red blood cells to be enumerated. In the 1970s, two techniques were developed for performing automated differential counts: digital image processing of microscope slides and flow cytometry techniques using light scattering and cell staining. These methods remain in use on modern hematology analyzers.
=== Discovery chemistry === BioDuro’s chemistry division supports medicinal chemistry, hit-to-lead, lead optimization, and synthetic route development. Its laboratories carry out small-molecule synthesis, peptide synthesis, and bioconjugation, including payload–linker development for antibody- drug conjugate (ADC) programs. The chemistry group works closely with DMPK and biology teams to support iterative design and structure- activity relationship (SAR) cycles.
==== Active metabolites ==== A few of the metabolites of oxycodone have also been found to be active as MOR agonists, some of which notably have much higher affinity for (as well as higher efficacy at) the MOR in comparison. Oxymorphone possesses 3- to 5-fold higher affinity for the MOR than does oxycodone, while noroxycodone and noroxymorphone possess one-third of and 3-fold higher affinity for the MOR, respectively, and MOR activation is 5- to 10-fold less with noroxycodone but 2-fold higher with noroxymorphone relative to oxycodone. Noroxycodone, noroxymorphone, and oxymorphone also have longer biological half-lives than oxycodone.
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.
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.