elevated plus maze 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 2025-11-28 and is reviewed periodically as new material appears.
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.
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 |
|---|---|---|
| Route studied | Intranasal | Predominant route in published reports |
| Circulation stability | Short, minutes scale | Peptidases cleave it; the tail slows the process |
| Analytical method | RP-HPLC with mass spectrometry | Used for identity and purity assessment |
| Reported outcome domains | Anxiety and cognitive measures | Derived from small, mostly regional trials |
| Regulatory status | Marketed in Russia | Availability outside that market is limited |
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
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.
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 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.
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.
Vitamin D toxicity, or hypervitaminosis D, is the toxic state of an excess of vitamin D. It is rare, having occurred historically during a time of unregulated fortification of foods, especially those provided to infants, or more recently, with consumption of high-dose vitamin D dietary supplements following inappropriate prescribing, non-prescribed consumption of high-dose, over-the-counter preparations, or manufacturing errors resulting in content far in excess of what is on the label. Ultraviolet light alone – sunlight or tanning beds – can raise serum 25(OH)D concentration to a bit higher than 100 nmol/L, but not to a level that causes hypervitaminosis D, the reasons being that there is a limiting amount of the precursor 7-dehydrocholesterol synthesized in the skin and a negative feedback in the kidney wherein the presence of calcitriol induces diversion to metabolically inactive 24,25-hydroxyvitamin D rather than metabolically active calcitriol (1,25-hydroxyvitamin D). Further metabolism yields calcitroic acid, an inactive water-soluble compound that is excreted in bile. There is no general agreement about the intake levels at which vitamin D may cause harm. According to the IOM review, "Doses below 10,000 IU/day are not usually associated with toxicity, whereas doses equal to or above 50,000 IU/day for several weeks or months are frequently associated with toxic side effects including documented hypercalcemia." The normal range for blood concentration of 25-hydroxyvitamin D in adults is 20 to 50 nanograms per milliliter (ng/mL; equivalent to 50 to 125 nmol/L).
They are said to exert influence both across all domains of experience and throughout the stages of each individual's unique development. Being in part based on heritable physiology, they are thought to have "existed" since humans became a differentiated species. They have been deduced through the development of storytelling over tens of thousands of years, indicating repeating patterns of individual and group experience, behaviours, and effects across the planet, apparently displaying common themes. Jung argued that the different stages of life (childhood, adolescence, adulthood etc.) are mediated through different archetypes.
Mary Engle Pennington (October 8, 1872 – December 27, 1952) was an American bacteriological chemist, food scientist and refrigeration engineer. She was an innovator in the preservation, handling, storage, and transportation of perishable foods and the first female lab chief at the U.S. Food and Drug Administration. She was awarded 5 patents (3 of which were shared), received the Notable Service Medal from President Herbert Hoover, and received the Garvin-Olin Medal from the American Chemical Society. She is an inductee of the National Inventor's Hall of Fame, the National Women's Hall of Fame and the ASHRAE Hall of Fame.
==== Australia ==== DET is considered a Schedule 9 prohibited substance in Australia under the Poisons Standard (October 2015). A Schedule 9 substance is a substance which may be abused or misused, the manufacture, possession, sale or use of which should be prohibited by law except when required for medical or scientific research, or for analytical, teaching or training purposes with approval of Commonwealth and/or State or Territory Health Authorities.
Sources: en.wikipedia.org
=== Fellows of ASMS (since 2025) === 2026 Veronica M. Bierbaum, Catherine E. Costello, Kristina Hakansson, Lisa M. Jones, Susan D. Richardson 2025 Erin S. Baker, Catherine C. Fenselau, P. Jane Gale, Susan Weintraub
==== Section B: Thermodynamics, Equipment and Systems ==== Section B on Thermodynamics, Equipment and Systems of the IIR focuses on the technological and scientific fundamentals of classical refrigeration, excluding cryogenic temperatures. The fundamentals are represented by its Commission B1 Thermodynamics and Transfer Processes, whereas Commission B2 Refrigerating Equipment covers all kinds of refrigeration technology. Section B is a key player in most of the IIR international conferences; except for the International Conference of Refrigeration (ICR), organised every four years for all 10 IIR Commissions, where approximately 50% of all presentations are related to Section B topics. Independently, and together with other Sections, Section B hosts a multitude of conferences such as the Gustav Lorentzen Conference on Natural Working Fluids and the Ohrid Conference on Ammonia and CO2 Refrigeration Technologies; or conferences on Thermodynamic Properties and Transfer Processes of Refrigerants, on Magnetic Refrigeration at Room Temperature, on Compressors and Coolants, and on Phase Change Materials and Slurries for Refrigeration and Air Conditioning. Several Working Groups, where emerging topics in refrigeration are discussed by IIR experts to publish results in handbooks or other forms of publications, are organised within the scope of Section B.
==== E ==== Powdered eggs – are fully dehydrated eggs made using spray drying in the same way that powdered milk is made. Powdered eggs have a storage life of 5 to 10 years when stored without oxygen in a cool environment. Another dried egg product is freeze-dried eggs, which can be shelf-stable for up to 25 years.
=== Electrical and electronics industry === Corona discharge on electrical apparatus can be detected by its ultraviolet emissions. Corona causes degradation of electrical insulation and emission of ozone and nitrogen oxide. EPROMs (Erasable Programmable Read-Only Memory) are erased by exposure to UV radiation. These modules have a transparent (quartz) window on the top of the chip that allows the UV radiation in.
In May 2007, Unilever became the first company to commit to sourcing all tea in a sustainable manner. Working with the Rainforest Alliance, an international environmental NGO, Unilever, announced all Lipton Yellow Label tea bags sold in Western Europe would be certified by 2010 and all Lipton tea bags sold globally by 2015. Lipton's own tea estates were among the first to be certified. Lipton tea bearing the Rainforest Alliance seal appeared on Western European markets in 2008 and started appearing in North America in 2009. On 6 May 2009, Lipton received a Corporate Green Globe Award for its work with the Rainforest Alliance. In 2011, PETA criticized Unilever for conducting and funding experiments on rabbits, pigs and other animals in an attempt to make human health claims about the tea's ingredients. According to the animal rights organization, Unilever decided to end the practice after receiving more than 40,000 appeals from PETA supporters and days before PETA made plans to launch its "Lipton CruelTEA" campaign. Unilever no longer tests their products on animals unless required to by governments as part of their regulatory requirements. Unilever reached an agreement in November 2021 to sell the majority of its tea business to private equity firm CVC Capital Partners for €4.5 billion. This included the Lipton brand except where Unilever retained its use for tea in India, Nepal, and Indonesia, for ready to drink teas globally, and for soup mixes in North America. The sale was completed in July 2022, with the new company named ‘Lipton Teas and Infusions’.
Sources: en.wikipedia.org
Reports describe effects on GABA-A receptor expression, monoamine turnover, and neurotrophic factor levels. These are proposed mechanisms drawn mainly from animal models. No single molecular target has been established.
Intranasal delivery is the route described in most published work. It is used because the peptide is degraded quickly once it reaches circulation. Direct evidence of brain penetration in humans is lacking.
Most trials are small, regionally concentrated, and often lack rigorous blinding or placebo control. Independent replication is limited. Reviews in English generally rate the evidence as preliminary.
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.