Everything below concerns GABA-A receptor. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-09-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
| 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 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.
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.
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.
‰ The KIE associated with diffusion reflects the mass difference of the heavy-isotope water molecules H2H16O and H218O relative to the normal isotopolog (H216O). After water evaporates to the air, condensation and precipitation transport it and return it to the surface. Water vapor condenses in ascending air masses that develop a lower temperature and saturation vapor pressure. Since the cooling and condensation happen relatively slowly, it is a process with equilibrium isotope effects. However, as water vapor is progressively condensed and lost from the air during moisture transport, the isotopic composition of the remaining vapor, as well as the resulting precipitation, can be largely depleted due to the process of Rayleigh distillation. The equation for Rayleigh distillation is:
Many species have so-called sex chromosomes that determine the sex of each organism. In humans and many other animals, the Y chromosome contains the gene that triggers the development of the specifically male characteristics. In evolution, this chromosome has lost most of its content and also most of its genes, while the X chromosome is similar to the other chromosomes and contains many genes. This being said, Mary Frances Lyon discovered that there is X-chromosome inactivation during reproduction to avoid passing on twice as many genes to the offspring. Lyon's discovery led to the discovery of X-linked diseases.
At the third AU summit, held in Tripoli, Libya, in July 2005, Gaddafi called for greater integration, advocating a single AU passport, a common defence system, and a single currency, using the slogan: "The United States of Africa is the hope." His proposal for a Union of African States, a project originally conceived by Ghana's Kwame Nkrumah in the 1960s, was rejected at the 2001 Assembly of Heads of States and Government (AHSG) summit in Lusaka by African leaders who thought it "unrealistic" and "utopian". In June 2005, Libya joined the Common Market for Eastern and Southern Africa (COMESA). In March 2008 in Uganda, Gaddafi gave a speech once again urging Africa to reject foreign aid. In August 2008, Gaddafi was proclaimed "King of Kings" by a committee of traditional African leaders; they crowned him in February 2009, in a ceremony held in Addis Ababa, Ethiopia. That same month, Gaddafi was elected as the chairperson of the African Union, a position he retained for one year. In October 2010, Gaddafi apologized to African leaders for the historical enslavement of Africans by the Arab slave trade.
Sources: en.wikipedia.org
The first of China's nuclear weapons tests took place in 1964, and its first hydrogen bomb test occurred in 1967 at Lop Nur. Tests continued until 1996, when the country signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT), but did not ratify it. The number of nuclear warheads in China's arsenal remains a state secret. There are varying estimates of the size of China's arsenal. The Bulletin of the Atomic Scientists and Federation of American Scientists estimated in 2024 that China has a stockpile of approximately 438 nuclear warheads, while the United States Department of Defense put the estimate at more than 500 operational nuclear warheads, making it the third-largest in the world. China's policy has traditionally been one of no first use while maintaining a deterrent retaliatory force targeted for countervalue targets. According to a 2023 study by the National Defense University, China's nuclear doctrine has historically leaned toward maintaining a secure second-strike capability.
Wiederrecht GJ, Brown GM (1984). "Purification and properties of the enzymes from Drosophila melanogaster that catalyze the conversion of dihydroneopterin triphosphate to the pyrimidodiazepine precursor of the drosopterins". J. Biol. Chem. 259 (22): 14121–7. doi:10.1016/S0021-9258(18)89865-9. PMID 6438092.
== Outpatient and home care == Today, chemotherapy is frequently given in outpatient clinics or taken at home as pills rather than during long hospital stays. It allows patients to recover in a more comfortable environment. Because of how the human body processes these medications, home care introduces unique safety needs. Chemotherapy drugs leave the patient’s system through body fluids like urine, stool, vomit, sweat, and saliva mostly during the first 24 hours to 7 days after treatment. Because these trace toxic chemicals can accidentally expose healthy family members through touch, shared surfaces or as aerosolized droplets during waste disposal, public health groups recommend basic safety habits at home. These typically include washing the patient's laundry separately, double-flushing toilets with the lid down, and having caregivers wear disposable gloves when handling body fluids. Epidemiological guidelines similarly address residential sexual intimacy and recommend basic safety habits to prevent healthy partners from absorbing the medicine, noting that because teratogenic trace elements are shed via saliva, semen, vaginal secretions and other body fluids, oncologists mandate the temporary use of barrier contraceptives and avoiding deep kissing during the drug-clearance window to prevent healthy partner exposure and avoid potential fetal complications. Consequently, family members are advised to avoid close contact or kissing if they show any signs of illness, such as a cold or cold sore, to keep the patient safe from secondary infections.
Sources: en.wikipedia.org
=== Early clinical trials, supply and the transfer to BMS === Phase I clinical trials began in April 1984, and the decision to start Phase II trials was made a year later. These larger trials needed more bark and collection of a further 12,000 pounds was commissioned, which enabled some phase II trials to begin by the end of 1986. But by then it was recognized that the demand for taxol might be substantial and that more than 60,000 pounds of bark might be needed as a minimum. This unprecedentedly large amount brought ecological concerns about the impact on yew populations into focus for the first time, as local politicians and foresters expressed unease at the program. The first public report from a phase II trial in May 1988 showed promising effects in melanoma and refractory ovarian cancer. At this point, Gordon Cragg of the NCI's Natural Product Branch calculated the isolation of enough taxol to treat all the ovarian cancer and melanoma cases in the US would require the destruction of 360,000 trees annually. For the first time, serious consideration was given to the problem of supply.
== See also == Artificial intelligence in Brazilian industry Artificial intelligence industry in India Artificial intelligence industry in Italy Artificial intelligence industry in Taiwan Artificial intelligence industry in Canada Parliamentary Under-Secretary of State for AI and Digital Government Science and technology in the United Kingdom
Morgan State University (MSU) is a historically black college in Baltimore, Maryland. It was founded in 1867 as the Centenary Biblical Institute, a Methodist Episcopal seminary, to train young men in the ministry. At the time of his death, Thomas Kelso, co-founder and president of the board of directors, endowed the Male Free School and Colored Institute through a legacy of his estate. It later broadened its mission to educate both men and women as teachers. The school was renamed as Morgan College in 1890 in honor of the Reverend Lyttleton Morgan, the first chairman of its board of trustees, who donated land to the college. In 1895, the institution awarded its first baccalaureate degree to George W. F. McMechen, after whom the building of the school of business and management is named today. McMechen later earned a law degree from Yale University and, after establishing his career, became one of Morgan's main financial supporters. John O. Spencer became the fifth president of Morgan College in 1902, and served in that position until 1937. In 1902, Morgan's assets were a little over $100,000 in grounds, equipment and endowments, including its branch schools at the time; the then Princess Anne Academy and the Virginia Collegiate and Industrial Institute. During his tenure as president, the university saw major expansions across the campus. By 1937, the school's assets were more than $1,000,000 and its enrollment had grown from 150 to 487.
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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, designed as a metabolically stabilized analogue of the endogenous tetrapeptide tuftsin. It has been studied mainly against anxiety-related and cognitive endpoints rather than as an approved medicine in most jurisdictions.