The short version of Neurotrophic factor fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-03-01 and is reviewed periodically as new material appears.
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.
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.
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 |
|---|---|---|
| Primary route studied | Intranasal | Also examined parenterally in animal work |
| Reported plasma half-life | Minutes to tens of minutes | Values vary widely between reports |
| Main model systems | Rodent behavioural and cell assays | Human trials are few and small |
| Principal proposed targets | GABA-A receptor, GABA transaminase | Monoamine and neurotrophic pathways also reported |
| Evidence grade | Preliminary | Limited independent replication |
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
Once dissolved, the peptide is markedly less stable than the dry powder. Aqueous solutions are subject to backbone hydrolysis and to microbial growth when they are handled without sterile technique. Buffered solutions near neutral pH are common for short-term laboratory work, while acidic conditions are sometimes used to improve solubility. Analytical laboratories generally prepare working solutions fresh rather than storing them, and a residual water film left in a reopened vial can seed degradation even when the container appears dry.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
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.
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
Recent economic growth has led to a considerable increase of new millionaires, including the new entrepreneurs, Colombians with a net worth exceeding US$1 billion. In 2017, however, the National Administrative Department of Statistics (DANE) reported that 26.9% of the population were living below the poverty line, of which 7.4% were in "extreme poverty". The multidimensional poverty rate stands at 17.0 percent of the population. The Government has also been developing a process of financial inclusion within the country's most vulnerable population. The contribution of tourism to GDP was US$5,880.3bn (2.0% of total GDP) in 2016. Tourism generated 556,135 jobs (2.5% of total employment) in 2016. Foreign tourist visits were predicted to have risen from 0.6 million in 2007 to 4 million in 2017.
An independent panel upholds the Parliamentary Commissioner for Standards' decision that Scott Benton, MP for Blackpool South, should face a 35-day suspension from Parliament. The suspension will now be voted on by MPs and could trigger another by-election. Heather Woodbridge, aged 29, is appointed as leader of Orkney Islands Council, becoming Scotland's youngest council leader and the first woman to lead Orkney Islands Council. 21 February – An Opposition day House of Commons debate calling for a ceasefire in Gaza descends into chaos after Speaker Sir Lindsay Hoyle breaks with Parliamentary convention to allow a vote on a Labour amendment calling for an "immediate humanitarian ceasefire" over the scheduled SNP motion calling for an "immediate ceasefire". The decision leads to protests from both Conservative and SNP MPs, who walk out of the House, leaving Labour's motion to be nodded through when the other two parties do not take part in the vote. Amid calls for his resignation, Hoyle says that he allowed the House to vote on the Labour motion so MPs could express their view on "the widest range of propositions", and to protect MPs' safety. King Charles III is seen back at work and meeting Prime Minister Rishi Sunak, the first time he has been seen back at work since his cancer diagnosis. Senior civil servant Sarah Munby writes to the Business Secretary to reject allegations by former Post Office chairman Henry Staunton that he was told to delay compensation payments to victims of the Horizon scandal.
== Future == Rönnberg has stated there will not be a sequel to Cry of Fear, as he considers the story completed. A remake was in development by Team Psykskallar, but production time and cost surpassed the original game and the project was abandoned. In August 2023, Rönnberg revealed he has been planning a new horror game, similar to both Afraid of Monsters and Cry of Fear, and the game was currently in the early writing phase.
The history of biology traces the study of the living world from ancient to modern times. Although the concept of biology as a single coherent field arose in the 19th century, the biological sciences emerged from traditions of medicine and natural history reaching back to Ayurveda, ancient Egyptian medicine and the works of Aristotle, Theophrastus and Galen in the ancient Greco-Roman world. This ancient work was further developed in the Middle Ages by Muslim physicians and scholars such as Avicenna. During the European Renaissance and early modern period, biological thought was revolutionized in Europe by a renewed interest in empiricism and the discovery of many novel organisms. Prominent in this movement were Vesalius and Harvey, who used experimentation and careful observation in physiology, and naturalists such as Linnaeus and Buffon who began to classify the diversity of life and the fossil record, as well as the development and behavior of organisms. Antonie van Leeuwenhoek revealed by means of microscopy the previously unknown world of microorganisms, laying the groundwork for cell theory. The growing importance of natural theology, partly a response to the rise of mechanical philosophy, encouraged the growth of natural history (although it entrenched the argument from design). Over the 18th and 19th centuries, biological sciences such as botany and zoology became increasingly professional scientific disciplines. Lavoisier and other physical scientists began to connect the animate and inanimate worlds through physics and chemistry.
Androgens are involved in prostate-related conditions such as benign prostatic hyperplasia (BPH), chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and prostate cancer. In BPH, C21 11-oxygenated steroids (pregnanes) have been identified are precursors to androgens. Specifically, steroids like 11β-hydroxyprogesterone (11OHP4) and 11-ketoprogesterone (11KP4) can be converted to 11-ketodihydrotestosterone (11KDHT), an 11-oxo form of DHT with the same potency. These precursors have also been detected in tissue biopsy samples from patients with BPH, as well as in their serum levels. The relationship between steroid serum levels and CP/CPPS suggests that deficiencies in the enzyme CYP21A2 may contribute to the development of this condition. Non-classical congenital adrenal hyperplasia (CAH) resulting from CYP21A2 deficiency is typically considered asymptomatic in men. However, non-classical CAH could be a comorbidity associated with CP/CPPS.
Sources: en.wikipedia.org
Early diagnosis is difficult, as the disease often first appears like a simple superficial skin infection. While several labs and imaging can raise the suspicion for necrotizing fasciitis, none can rule it out. The gold standard for diagnosis is a surgical exploration and subsequent tissue biopsy. When in doubt, a 2-cm incision can be made into the affected tissue under local anesthesia. If a finger easily separates the tissue along the fascia, then the finger test is positive. This confirms the diagnosis, and an extensive debridement should be performed.
== Computer System Validation == This requirement has naturally expanded to encompass computer systems used both in the development and production of, and as a part of pharmaceutical products, medical devices, food, blood establishments, tissue establishments, and clinical trials. In 1983 the FDA published a guide to the inspection of Computerized Systems in Pharmaceutical Processing, also known as the 'bluebook'. Recently both the American FDA and the UK Medicines and Healthcare products Regulatory Agency have added sections to the regulations specifically for the use of computer systems. In the UK, computer validation is covered in Annex 11 of the EU GMP regulations (EMEA 2011). The FDA introduced 21 CFR Part 11 for rules on the use of electronic records, electronic signatures (FDA 1997). The FDA regulation is harmonized with ISO 8402:1994, which treats "verification" and "validation" as separate and distinct terms. On the other hand, many software engineering journal articles and textbooks use the terms "verification" and "validation" interchangeably, or in some cases refer to software "verification, validation, and testing (VV&T)" as if it is a single concept, with no distinction among the three terms.
Freeman returned to the screen in 2000 with the lead role of Charlie in the comedy Nurse Betty, featuring Renée Zellweger, Chris Rock, and Greg Kinnear. The film premiered at the Cannes Film Festival to mainly positive reviews; the critic from Variety magazine thought Freeman and Rock had "wonderful chemistry". Next, he appeared in Under Suspicion (2000), a thriller remake of the 1981 French film Garde à vue. The film had been "carting round" for twelve years before Freeman was able to produce it under Revelations Entertainment. He co-starred with Gene Hackman; "Working with Gene was wonderful. I didn't find it too hard working with an icon I so respected", Freeman said. Upon release, Under Suspicion was met with lukewarm reception; CNN's Paul Tatara praised the actors but thought the film was "too tawdry to be completely entertaining, and too static to generate much excitement".
Assist with Post Mortem Examinations Preparation and Operation of a Mortuary Prepare for Post Mortem Examinations Team Working Viewing of the Deceased In addition to formal training, dieners learn how to do basic tasks through shadowing a mentor.
Sources: en.wikipedia.org
== Action mechanism, pharmacokinetics == Like other local anesthetics belonging in the amide group trimecaine decreases the cell membrane permeability, causes depolarization and shortens the action potential. Anesthetic effect starts within 15 minutes and remains 60–90 minutes. Its biological half-life is ca. 90 minutes. 10% of trimecaine is excreted unchanged (90% as its metabolites). It passes through the hematoencephalic and placental barriers.
== Income, wealth and income distribution == Average per capita income is high in an international context. According to the World Bank, gross national income per capita was the tenth-highest in the world at $55,220 in 2017. Correcting for purchasing power, income was Int$52,390 or 16th-highest among the 187 countries. During the last three decades household saving rates in Denmark have increased considerably. This is to a large extent caused by two major institutional changes: A series of tax reforms from 1987 to 2009 considerably reduced the effective subsidization of private debt implicit in the rules for tax deductions of household interest payments. Secondly, compulsory funded pension schemes became normal for most employees from the 1990s. Over the years, the wealth of the Danish pension funds have accumulated so that in 2016 it constituted twice the size of Denmark's GDP. The pension wealth consequently is a very important both for the life-cycle of a typical individual Danish household and for the national economy. A large part of the pension wealth is invested abroad, thus giving rise to a fair amount of foreign capital income. In 2015, average household assets were more than 600% of their disposable income, among OECD countries second only to the Netherlands. At the same time, average household gross debt was almost 300% of disposable income, which is also at the highest level in OECD. Household balance sheets are consequently very large in Denmark compared to most other countries.
Most well-nourished people in industrialized countries have 4 to 5 grams of iron in their bodies (~38 mg iron/kg body weight for women and ~50 mg iron/kg body for men). Of this, about 2.5 g is contained in the hemoglobin needed to carry oxygen through the blood (around 0.5 mg of iron per mL of blood), and most of the rest (approximately 2 grams in adult men, and somewhat less in women of childbearing age) is contained in ferritin complexes that are present in all cells, but most common in bone marrow, liver, and spleen. The liver stores of ferritin are the primary physiologic source of reserve iron in the body. The reserves of iron in industrialized countries tend to be lower in children and women of child-bearing age than in men and in the elderly. Women who must use their stores to compensate for iron lost through menstruation, pregnancy or lactation have lower non-hemoglobin body stores, which may consist of 500 mg, or even less. Of the body's total iron content, about 400 mg is devoted to cellular proteins that use iron for important cellular processes like storing oxygen (myoglobin) or performing energy-producing redox reactions (cytochromes). A relatively small amount (3–4 mg) circulates through the plasma, bound to transferrin. Because of its toxicity, free soluble iron is kept in low concentration in the body. Iron deficiency first affects the storage of iron in the body, and depletion of these stores is thought to be relatively asymptomatic, although some vague and non-specific symptoms have been associated with it.
Sources: en.wikipedia.org
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.
The peptide enters plasma rapidly and is broken down by ordinary proteases into amino acids and shorter fragments. Reported half-lives are short. Whether meaningful amounts of the intact molecule reach the brain is an open question.
Most clinical reports are small, published in Russian and not independently replicated. English-language reviews highlight the absence of large randomised trials. Conclusions about efficacy should be treated as provisional.
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.