A practical reference on anxiolytic: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-04-10 and is reviewed periodically as new material appears.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
Quality assessment of Selank samples typically combines purity determination with identity confirmation and counter-ion analysis. Purity is usually reported as a percentage by chromatographic area, with values above 95 percent often quoted for research-grade material. Water content and residual solvents are checked in lyophilized batches because they affect both stability and accurate mass determination. A reported purity figure does not by itself establish that a sample is the intended sequence, so orthogonal methods are needed to rule out sequence isomers or truncation products.
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
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.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | -20 °C or below | For lyophilized powder, long term |
| Common analytical method | Reverse-phase HPLC | Usually paired with mass spectrometry |
| Typical reported purity | At or above 95 percent by area | Research-grade material |
| Aqueous solubility | High | Solutions used in laboratory assays |
| Moisture sensitivity | Hydrolyzes in solution | Aseptic handling reduces degradation |
The primary structure of Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, corresponding to the molecular formula C33H57N11O9 and a monoisotopic mass of roughly 751.9 daltons. The N-terminal threonine and the arginine residue in the fourth position are shared with tuftsin, which carries the sequence Thr-Lys-Pro-Arg. The three additional residues at the C-terminus, Pro-Gly-Pro, extend the chain and are associated with greater resistance to enzymatic degradation. This extension also separates Selank from the shorter parent peptide.
Naming conventions place Selank in the same research family as Semax, another Russian-developed peptide investigated for cognitive effects. The two compounds share a lineage but differ in sequence and in the biological systems proposed as their targets. Semax descends from ACTH fragments, whereas Selank descends from tuftsin. Publications sometimes identify Selank by its full peptide sequence or by laboratory codes rather than one uniform trade name. Because replication outside Russia is limited, reports on its properties are best read alongside the study design and the purity of the material tested.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
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.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
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.
==== MeSH E05.318.780 – epidemiologic research design ==== MeSH E05.318.780.074 – control groups MeSH E05.318.780.150 – cross-over studies MeSH E05.318.780.300 – double-blind method MeSH E05.318.780.485 – matched-pair analysis MeSH E05.318.780.500 – meta-analysis MeSH E05.318.780.700 – random allocation MeSH E05.318.780.725 – reproducibility of results MeSH E05.318.780.762 – sample size MeSH E05.318.780.800 – sensitivity and specificity MeSH E05.318.780.800.650 – predictive value of tests MeSH E05.318.780.800.750 – roc curve MeSH E05.318.780.850 – single-blind method
== Medical uses == Vancomycin is indicated for the treatment of serious, life-threatening infections by Gram-positive bacteria of both aerobic and anaerobic types that are unresponsive to other antibiotics. The increasing emergence of vancomycin-resistant enterococci (VRE) has resulted in the development of guidelines for use by the Centers for Disease Control Hospital Infection Control Practices Advisory Committee. These guidelines restrict use of vancomycin to these indications:
=== Epilepsy === As an adjunctive therapy in epilepsy, it is used in patients who have not responded to first-line drugs and in children who are refractory to first-line drugs. It is unclear if there are any benefits to clobazam over other seizure medications for children. It is not recommended for use in children between the ages of six months and three years, unless there is a compelling need. Clobazam is approved in Canada (Frisium) for add-on use in tonic–clonic, complex partial, and myoclonic seizures. Clobazam is approved for adjunctive therapy in complex partial seizures, certain types of status epilepticus, specifically the myoclonic, myoclonic-absent, simple partial, complex partial, and tonic varieties, and non-status absence seizures. In the United States, clobazam (Onfi) was not marketed until October 2011 and was only approved for use in combination with other medications to control epilepsy in people aged two years of age and older who have Lennox–Gastaut syndrome.
Sources: en.wikipedia.org
==== Renaissance and Reformation (c. 1400–1550) ==== Johannes Gutenberg's moveable‐type printing press (c. 1450s) ushered in the information age and rise of newspapers. Conquest of Constantinople by the Ottoman Empire (1453) marked the fall of the Byzantine Empire. Christopher Columbus's first voyage to the Americas (1492) initiated sustained contact between Europe and the New World. Amerigo Vespucci's Mundus Novus letter (1503), the first explicit articulation in print of the hypothesis that the lands discovered by European navigators to the west were not the edges of Asia but rather an entirely different continent, is published. Niccolò Machiavelli's The Prince (c. 1513), a foundational work of modern political philosophy. Martin Luther's posting of the 95 Theses (1517) ignited the Reformation. The broader Age of Discovery saw unprecedented maritime exploration and early colonial empires. Nicolaus Copernicus's De revolutionibus orbium coelestium (1543) proposes that the Earth revolves around the Sun. Council of Trent (1545) begins the Catholic Counter-Reformation. Rise of Mercantilism as the prevailing economic theory.
These central and peripheral actions are associated with decreased plasma norepinephrine and reduced urinary catecholamine excretion, and with reductions in plasma renin and urinary aldosterone reported alongside decreases in total peripheral resistance and heart rate. With intravenous administration, clonidine may cause a short-lived increase in blood pressure attributed to α2 adrenoceptor-mediated vasoconstriction in vascular smooth muscle, followed by a more sustained hypotensive response once clonidine crosses the blood brain barrier and binds to its receptor sites in the medulla oblongata; this biphasic pattern is generally less evident with oral or transdermal routes of administration due to dilution of the drug before reaching circulation. In the prefrontal cortex, α2A is the predominant α2 adrenoceptor subtype, and clonidine's attention- and working memory-related effects are attributed to postsynaptic α2A activation. Across the brain more generally, α2A and α2C adrenoceptors are widely distributed, while α2B is primarily expressed in the thalamus. α2A adrenoceptors on dendritic spines of prefrontal pyramidal neurons can close hyperpolarization-activated cyclic nucleotide-gated channels (HCNs) to promote attentional control and working memory. The mechanism behind this behavioral effect has been described as the consequence of improved signal-to-noise ratio in the prefrontal cortex, which can facilitate focused attention on relevant stimuli and improved cognitive control of behavior.
At this time there is no direct evidence of a causative link between growth hormone and the respiratory problems seen in PWS (among both those receiving and those not receiving GH treatment), including sudden death. A follow-up sleep study after one year of GH treatment may also be indicated. GH (specifically Pfizer's version, Genotropin) is the only treatment that has received an FDA indication for children with PWS. The FDA indication only applies to children. Children short because of intrauterine growth retardation are small for gestational age at birth for a variety of reasons. If early catch-up growth does not occur and their heights remain below the third percentile by 2 or 3 years of age, adult height is likely to be similarly low. High-dose GH treatment has been shown to accelerate growth, but data on long term benefits and risks are limited. Idiopathic short stature (ISS) is one of the most controversial indications for GH as pediatric endocrinologists do not agree on its definition, diagnostic criteria, or limits. The term has been applied to children with severe unexplained shortness that will result in an adult height below the 3rd percentile. In the late 1990s, the pharmaceutical manufacturer Eli Lilly and Company sponsored trials of their brand of rHGH (Humatrope) in children with extreme ISS, those at least 2.25 standard deviations below mean (in the lowest 1.2 percent of the population). These boys and girls appeared to be headed toward heights of less than 160 cm and 150 cm respectively.
The officer commanding the Army of India was the Commander-in-Chief, India who reported to the civilian Governor-General of India. The title was used before the creation of a unified British Indian Army; the first reported holder was then-Major Stringer Lawrence in 1748. Lawrence went to India with no larger command than a "small undisciplined garrison of two or three hundred men" facing a significant French presence. In 1903, Lord Kitchener became the Commander-in-Chief of the Indian Army. He instituted large-scale reforms, the greatest of which was the merger of the three armies of the Presidencies into a unified force. He formed higher level formations, eight army divisions, and brigaded Indian and British units. He left his command in 1909. Following Kitchener's reforms, the terminology used for the forces in India was altered. The Indian Army referred from that time to "the force recruited locally and permanently based in India, together with its expatriate British officers;" the British Army in India referred to the British Army units posted to India for a tour of duty, and which would then be posted to other parts of the Empire or back to the UK. The Army of India was used to describe the combined forces of both the Indian Army and the British Army in India. By the early 1900s the three previous separate army staffs had been amalgamated into Headquarters, India (see 1906 Birthday Honours) which by 1922 had become GHQ India (see 1922 New Year Honours).
Sources: en.wikipedia.org
These findings mirror human epidemiological data showing a link between nicotine use and increased risk of later cannabis and cocaine use, as well as other substances. Similarly, in rats, alcohol consumption raises the probability of later cocaine addiction and is associated with changes in the brain's reward system. Human studies also show that alcohol use increases the risk of transitioning from cocaine use to addiction. Experimentally, cocaine injections can be delivered to animals such as fruit flies to study the mechanisms of cocaine addiction.
Despite getting a late start in publishing his research (he did not publish a paper until 10 years after finishing graduate school), Fenn had over 100 publications at the time of his death. He also wrote a book, entitled Engines, Energy, and Entropy: A Thermodynamics Primer. The Science History Institute Museum in Philadelphia, PA has the instrument Fenn and his graduate students built while they were developing electrospray ionization on display, after receiving it as a gift from Fenn.
Along with Mastodon and Deftones, Alice in Chains toured the United States and Canada in late 2010 on the Blackdiamondskye tour, an amalgam of the three bands' latest album titles (Black Gives Way to Blue, Diamond Eyes, and Crack the Skye). On March 8, 2011, former Alice in Chains bassist Mike Starr was found dead at his home in Salt Lake City. Police told Reuters they were called to Starr's home at 1:42 pm and found his body; Starr was 44. Reports later surfaced that Starr's roommate had seen him mixing methadone and anxiety medication hours before he was found dead. Later reports indicated Starr's death may have been linked to two different types of antidepressants prescribed to him by his doctor. A public memorial was held for Starr at the Seattle Center's International Fountain on March 20, 2011. A private memorial was also held, which Jerry Cantrell and Sean Kinney attended according to Mike Inez.
As of 2018, there are around 470 million pet dogs. Pet food production is responsible for 20–30% of the environmental impacts from animal production. It has been estimated that global greenhouse gas emissions from dog and cat dry food represents around 1.1%−2.9% of global emissions, an amount close to the total emissions of countries such as Mozambique or the Philippines. Like humans, dogs are omnivores. There is research on alternative protein sources for pet food including insects and algae. A life-cycle analysis of contemporary pet foods suggests wet foods for cats and dogs tend to have a larger impact than dry foods. It also suggests there are substantial opportunities for improvement in "all phases of the pet food life cycle, including formulation, ingredient selection, manufacturing processes" and so on.
Mizell led the league in strikeouts with 257, finished second in ERA to Tom Gorman (1.97 to 1.94), and tied for seventh in the league with 16 wins. With a record of 99–61, Houston won the pennant by 13.5 games over the San Antonio Missions.
Sources: en.wikipedia.org
The most common approach combines reverse-phase liquid chromatography with mass spectrometry. Chromatography separates the components while mass spectrometry confirms the molecular mass. Peptide sequencing or tandem mass analysis can further verify the amino acid order.
Lyophilized powder is usually kept frozen and protected from moisture. Solutions are less stable and are often used promptly or divided into aliquots to avoid repeated freeze-thaw cycles. Exact shelf-life values depend on purity and handling.
No. A purity figure derived from chromatographic area does not prove the amino acid sequence. Identity requires an orthogonal method such as mass spectrometry or sequencing. Truncated or isomerized peptides can co-elute with the target compound.
Selank is a synthetic peptide made of seven amino acids. It is modeled on tuftsin, a natural tetrapeptide, with an added three-residue tail. It is not a small-molecule drug.