elevated plus maze is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-05-19. Numbers and descriptions here follow the published literature rather than marketing material.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
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.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Reversed-phase HPLC retention time versus reference standard | Retention depends on column, gradient, and ion-pairing agent |
| Mass confirmation | Electrospray or MALDI mass spectrometry | Doubly protonated ion near m/z 377 is consistent with about 752 Da |
| Typical purity specification | 95 percent or higher by chromatographic peak area | Lower values suggest truncated or modified peptide species |
| Storage of lyophilized powder | -20 °C, desiccated, protected from light | Powder tolerates long storage better than solution |
| Storage of solution | 2-8 °C for short periods | Freeze-thaw cycling promotes aggregation and surface adsorption |
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.
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.
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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
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.
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.
=== Mosquitoes === Methods of resistance include thickening of the cuticle of the insect to limit permeation of the insecticide, metabolic resistance via overexpression of metabolizing cytochrome P450 mono-oxygenases and glutathione-S-transferases, and the knockdown resistance (kdr) sodium channel mutations which render the action of insecticides ineffectual, even when co-administered with piperonyl butoxide. Characterization of the different forms of resistance among mosquitoes has become a top priority in groups studying tropical medicine due to the high mortality of those who reside in endemic areas.
Other investigational drugs using RNAi that are being developed by pharmaceutical companies such as Arrowhead Pharmaceuticals, Dicerna, Alnylam Pharmaceuticals, Amgen, and Sylentis. These medications cover a variety of targets via RNAi and diseases. Investigational RNAi therapeutics in development:
Thus, irisin was found to positively regulate the expression of BDNF and negatively influence the levels of GHbA1c (human glycated hemoglobin A1c) and AGEs, suggesting that irisin influences cognitive dysfunction in rats with type 2 diabetes by regulating the expression of BDNF and glycometabolism. It appears that these proteins are connected and related to each other in terms of cardiovascular/metabolic diseases, such as hypertension and diabetes.
Half shade device: It consist of two semicircular plates ACB and ADB. One half ACB is made of glass while other half is made of quartz. Both halves are cemented together. The quartz is cut parallel to the optic axis. Thickness of the quartz is selected in such a way that it introduces a path difference of ’A/2 between ordinary and extraordinary ray. The thickness of the glass is selected in such a way that it absorbs the same amount of light as is absorbed by the quartz half. Consider that the vibration of polarization is along OP. On passing through the glass half the vibrations remain along OP. But on passing through the quartz half these vibrations will split into 0- and £-components. The £-components are parallel to the optic axis while O- component is perpendicular to optic axis. The O-component travels faster in quartz and hence an emergence 0-component will be along OD instead of along OC. Thus components OA and OD will combine to form a resultant vibration along OQ which makes the same angle with optic axis as OP. Now if the Principal plane of the analyzing Nicol is parallel to OP then the light will pass through the glass half unobstructed. Hence the glass half will be brighter than the quartz half or we can say that the glass half will be bright and the quartz half will be dark. Similarly if the principal plane of the analyzing Nicol is parallel to OQ then the quartz half will be bright and the glass half will be dark. When the principal plane of the analyzer is along AOB then both halves will be equally bright.
Sources: en.wikipedia.org
=== West Asia === In Saudi Arabia, about 4.2% of the population carries the sickle cell trait, and 0.26% have sickle cell disease. The highest prevalence is in the Eastern province, where approximately 17% of the population carries the gene and 1.2% have sickle cell disease. In 2005, Saudi Arabia introduced a mandatory premarital test including HB electrophoresis, which aimed to decrease the incidence of sickle cell disease and thalassemia. In Bahrain, a study published in 1998 that covered about 56,000 people in hospitals in Bahrain found that 2% of newborns have sickle cell disease, 18% of the surveyed people have the sickle cell trait, and 24% were carriers of the gene mutation causing the disease. The country began screening of all pregnant women in 1992, and newborns started being tested if the mother was a carrier. In 2004, a law was passed requiring couples planning to marry to undergo free premarital counselling. These programmes were accompanied by public education campaigns.
== University presidents and administrators == John M. Mason (1789), provost of Columbia College and president of Dickinson College Philip Milledoler (1793), fifth president of Rutgers University Nathaniel Fish Moore (1802), eighth President of Columbia University Isaac Ferris (1816), third president of New York University James Hall Mason Knox (1841), 8th president of Lafayette College John Aikman Stewart (1841), businessman, banker, acting president of Princeton University John Howard Van Amringe (1860), mathematician and dean of Columbia College Seth Low (1870), president of Columbia University and mayor of New York City Nicholas Murray Butler (1882), president of Columbia University, chairman of the Carnegie Endowment for International Peace and Nobel Peace Prize winner, founder of Horace Mann School and the College Board Francis Lister Hawks Pott (1883), Episcopal missionary and president of St. John's University, Shanghai 1888–1941 Thomas Fiske (1885), professor of mathematics at Columbia University; acting dean of Barnard College; president of the American Mathematical Society 1902–1904; secretary of the College Board Frank Pierrepont Graves (1890), former president of the University of Washington, University of Wyoming; commissioner of Education of the State of New York 1921–1940 Frank D. Fackenthal (1906), acting president of Columbia University Dixon Ryan Fox (1911), Union College president 1934–1945 Louis L.
Increased pressure also plays a roles in many diabetic foot ulcerations as changes due to the disease causes the foot to have limited joint mobility and creates pressure points on the bottom of the foot. Effective measures to treat this includes a surgical procedure called the gastrocnemius recession in which the calf muscle is lengthened to decrease the fulcrum created by this muscle and resulting in a decrease in plantar forefoot pressure.
Create a core breeding population of important buffalo breeds. Conducts comprehensive research on buffalo breeding and production, and transfer technology to the farmers, herders, institutes, NGOs, etc. Collate and disseminate comprehensive information on buffalo.
Lindow Man, also known as Lindow II and (in jest) as Pete Marsh, is the preserved bog body of a man discovered in a peat bog at Lindow Moss near Wilmslow in Cheshire, North West England. The remains were found on 1 August 1984 by commercial peat cutters. Lindow Man is not the only bog body to have been found in the moss; Lindow Woman was discovered the year before, and other body parts have also been recovered. The find was described as "one of the most significant archaeological discoveries of the 1980s" and caused a media sensation. It helped invigorate the study of British bog bodies, which had previously been neglected. Dating the body has proven problematic, but it is thought that he was deposited into Lindow Moss, face down, sometime between 2 BC and 119 AD, in either the Iron Age or Romano-British period. At the time of death, Lindow Man was a healthy male in his mid-20s, and may have been of high social status as his body shows little evidence of having done heavy or rough physical labour during his lifetime. There has been debate over the reason for his death; his death was violent and perhaps ritualistic. The recovered body has been preserved by freeze-drying and is on permanent display at the British Museum, although it occasionally travels to other venues such as the Manchester Museum.
Sources: en.wikipedia.org
== Hosting == Hanoi has hosted the Vietnam National Games five times in 1985, 1990, 1995, 2002 and 2018. The other provinces & cities to have hosted the Vietnam National Games are Đà Nẵng, Nam Định (now Ninh Bình), Quảng Ninh, and Ho Chi Minh City. with provinces & cities having hosted only one occasion. The 10th Vietnam National Games in Ho Chi Minh City will mark the second time on which the Vietnam National Games have been hosted.
telophase The final stage of cell division in both mitosis and meiosis, occurring after anaphase and before or simultaneously with cytokinesis, during which a nuclear membrane is synthesized around each set of chromatids, nucleoli are reassembled, and the mitotic spindle is disassembled. Following cytokinesis, the new daughter cells resume interphase.
Electroluminescence from a solid state diode was discovered in 1906 by Henry Joseph Round of Marconi Labs, and was published in February 1907 in Electrical World. Round observed that various carborundum (silicon carbide) crystals would emit yellow, light green, orange, or blue light when a voltage was passed between the poles. A silicon carbide LED was created by Soviet inventor Oleg Losev in 1927. Commercially viable LEDs only became available after Texas Instruments engineers patented efficient near-infrared emission from a diode based on GaAs in 1962. Commercial LEDs were extremely costly and saw no practical use until Monsanto and Hewlett-Packard developed them to the point where a unit cost less than five cents in the 1970s. In the early 1990s, Shuji Nakamura, Hiroshi Amano and Isamu Akasaki developed blue light-emitting diodes, bringing white lighting and full-color LED displays into practical use. For this work, they won the 2014 Nobel Prize in Physics.
For services to Education. Donna Jones. Team Leader, Ministry of Defence. For services to Defence. Janet Elizabeth Kay. Kinship Carer, Kinship. For services to Children and Families. Professor Simon Edward Kenny. National Clinical Director for Children and Young People, NHS England and Consultant Paediatric Surgeon, Alder Hey Children's Hospital. For services to Paediatric Surgery. Professor Bienvenido Arturo Langa Ferreira. Consultant Psychiatrist, NHS Lanarkshire. For services to Vulnerable People in Scotland. Nicholas David Leader. Lately Governor, HM Prison Berwyn. For Public Service. Kathryn Maria Leahy. Director of Operations, Heathrow Airport. For services to Aviation Transport and to Major Events. Cathryn Lee. Chief Executive, Alzheimer's Society. For services to Charity. Janet Legrand, KC. Lately Chair of Trustees, The Children's Society. For services to Young People. Carl Anthony Les. Leader, North Yorkshire Council. For services to Local Government. Philip John Loach, QFSM. Lately Chief Fire Officer, West Midlands Fire and Rescue Service. For services to Fire and Rescue. Dr. William Patrick James Lockhart. Deputy Director, International Biodiversity and Wildlife, Department for Environment, Food and Rural Affairs. For services to the Environment. Antony Craig Lockley. Director of Strategy and Assistant Chief Executive, Blackpool Council. For services to Local Government. Professor Mark Logan, FRSE. Chief Entrepreneurial Adviser to the Scottish Government. For services to the Economy. Sally-Ann Loudon.
Sources: en.wikipedia.org
Identity is confirmed by matching the retention time in reversed-phase chromatography against a reference standard and by measuring the molecular mass with mass spectrometry. Tandem mass spectrometry or amino acid analysis can verify the sequence of the seven residues. Because the peptide contains no aromatic amino acids, detection at 280 nm is not useful.
Lyophilized powder is normally stored desiccated at -20 °C, protected from light and moisture. Powder kept under these conditions is generally stable for long periods. Solutions are less stable and are usually prepared immediately before use.
A purity value from one chromatographic method does not capture every possible impurity. Related peptides with similar retention behavior, counterions, and residual solvents may not appear in the same analysis. Independent testing with an orthogonal method provides stronger assurance of identity and content.
Dry powder is best kept sealed, protected from light, and held at minus 20 degrees Celsius or below. Desiccant packaging helps limit moisture uptake because the material is hygroscopic. A sealed vial should be allowed to equilibrate to room temperature before opening to reduce condensation.