peptidase 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 2026-05-12 and is reviewed periodically as new material appears.
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.
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.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
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.
| Property | Value | Notes |
|---|---|---|
| Principal proposed target | GABA-A receptor complex | Hypothesis derived mainly from animal pharmacology |
| Common behavioral assay | Elevated plus maze | Rodent test for anxiety-like behavior |
| Reported molecular marker | Hippocampal BDNF expression | Measured by immunoassay or mRNA quantification |
| Typical dosing route | Intranasal | Chosen to reduce first-pass metabolism |
| Reported plasma half-life | Minutes | Based on limited peptide stability data |
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.
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.
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.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
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.
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.
the "hot dog" was quickly inserted in a gash in a roll and in other newspapers in 1893. This makes the legend that hot dog was coined by the newspaper cartoonist Thomas Aloysius "Tad" Dorgan around 1900 impossible; Dorgan's earliest documented use of hot dog was in 1906.
[xanthine oxidase] + 2 glutathione Thus, the two substrates of this enzyme are xanthine dehydrogenase and glutathione disulfide, whereas its two products are xanthine oxidase and glutathione. This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with a disulfide as acceptor. The systematic name of this enzyme class is [xanthine-dehydrogenase]:glutathione-disulfide S-oxidoreductase. Other names in common use include [xanthine-dehydrogenase]:oxidized-glutathione S-oxidoreductase, enzyme-thiol transhydrogenase (oxidized-glutathione), glutathione-dependent thiol:disulfide oxidoreductase, and thiol:disulfide oxidoreductase. This enzyme participates in glutathione metabolism.
==== Serotonin binding to 5-HT2C ==== Serotonin is an endogenous non-selective agonist for the 5-HT2C receptor with a binding constant of Ki = 16.0 nM. When serotonin binds to the receptors, the most important contacts are in TM helixes 3, 5 and 6 (Figure 3), while the other four TM helixes do not interact directly with the serotonin compound. When binding of serotonin takes place, the protonated primary amine site forms a salt bridge with D134 residue in TM 3, as well as forming a hydrogen bond with residue S138 in TM 3. The aromatic indole ring forms a strong Van der Waals interaction with residues F223 in TM 5 and F328 in TM 6. The ring falls tight into the receptor pocket, stacked between two phenylalanines. Amine of the indole group forms a hydrogen bond with S219 residue in TM 5 and hydroxide substituent of the indole forms hydrogen bonds both with residue S131 in TM 3 and I332 in TM 6. There is also a strong Van der Waals interaction between the indole and I332 in TM 6.
While the "ness team" began moving to Bawdsey, the Orfordness site remained in use. This proved useful during one demonstration when the new system recently completed at Bawdsey failed. The next day, Robert Hanbury-Brown and the new recruit Gerald Touch started up the Orfordness system and were able to run the demonstrations from there. The Orfordness site was not closed until 1937.
=== Dental implants === The most common use of bone grafting is in the application of dental implants to restore the edentulous area of a missing tooth. Dental implants require bones underneath them for support and proper integration into the mouth. As mentioned earlier bone grafts come in various forms such as autologous (from the same person), Allograft, Xenograft (mainly bovine bone), and Alloplastic materials. Bone grafts can be used prior to implant placement or simultaneously. People who have been edentulous (without teeth) for a prolonged period may not have enough bone left in the necessary locations. In this case, autologous bone can be taken from the chin, from the pilot holes for the implants, or even from the iliac crest of the pelvis and inserted into the mouth underneath the new implant. Alternatively, exogenous bone can be used: xenograft is the most commonly used, because it offers the advantage of exceptional volume stability over time. Allograft offers the best regeneration quality but has lower volume stability. Often a mix of different kinds of bone grafts is used. In general, bone graft is either used en bloc (such as from the chin or the ascending ramus area of the lower jaw) or particulated, in order to be able to adapt it better to a defect. Dental bone grafting is a specialized oral surgical procedure that has been developed to reestablish lost jawbone. This loss can be a result of dental infection of abscess, periodontal disease, trauma, or the natural process of aging.
Sources: en.wikipedia.org
== After WWII == In 1968, Victor Saxl died and Eva moved to Santiago, Chile, to live with her brother, her only living relative. There she would remain vigilant as an advocate for people with Type 1 diabetes. Eva Saxl died in 2002 in Santiago. The Saxls' story was dramatized by the 1956–1958 CBS television show Telephone Time in an episode titled "Time Bomb".
The hormone vasopressin also stimulates the activity of NKCC2. Vasopressin stimulates sodium chloride reabsorption in the thick ascending limb of the nephron by activating signaling pathways. Vasopressin increases the traffic of NKCC2 to the membrane and phosphorylates some serine and threonine sites on the cytoplasmic N-terminal of the NKCC2 located in the membrane, increasing its activity. Increased NKCC2 activity aids in water reabsorption in the collecting duct through aquaporin 2 channels by creating a hypo-osmotic filtrate.
Tweezing (hairs are tweezed, or pulled out, with tweezers or with fingers) Waxing (a hot or cold layer is applied and then removed with porous strips) Sugaring (hair is removed by applying a sticky paste to the skin in the direction of hair growth and then peeling off with a porous strip) Threading (also called fatlah or khite in Arabic, or band in Persian) in which a twisted thread catches hairs as it is rolled across the skin Epilators (mechanical devices that rapidly grasp hairs and pull them out). Drugs that directly attack hair growth or inhibit the development of new hair cells. Hair growth will become less and less until it finally stops; normal depilation/epilation will be performed until that time. Hair growth will return to normal if use of product is discontinued. Products include the following: The pharmaceutical drug eflornithine hydrochloride (with the trade names Vaniqa and Follinil) inhibits the enzyme ornithine decarboxylase, preventing new hair cells from producing putrescine for stabilizing their DNA. Antiandrogens, including spironolactone, cyproterone acetate, flutamide, bicalutamide, and finasteride, can be used to reduce or eliminate unwanted body hair, such as in the treatment of hirsutism. Although effective for reducing body hair, antiandrogens have little effect on facial hair. However, slight effectiveness may be observed, such as some reduction in density/coverage and slower growth. Antiandrogens will also prevent further development of facial hair, despite only minimally affecting that which is already there.
Also, gas chimneys have been reported, and exploratory wells have discovered sub-commercial gas accumulations and pockmarks along fault planes. A sound geological and geophysical understanding of the Foz do Amazonas Basin is already available and used by the energy companies. Exploration of new areas, such as potential seep sites off of the east coast of the U.S. and the Laurentian fan where chemosynthetic communities are known deeper than 3,500 m (11,500 ft), and shallower sites in the Gulf of Guinea are need to study in the future.
In advanced cases, bulging of the cornea can result in a localized rupture of Descemet's membrane, an inner layer of the cornea. Aqueous humor from the eye's anterior chamber seeps into the cornea before Descemet's membrane reseals. The patient experiences pain and a sudden severe clouding of vision, with the cornea taking on a translucent milky-white appearance known as a corneal hydrops. Although disconcerting to the patient, the effect is normally temporary and after a period of six to eight weeks, the cornea usually returns to its former transparency. The recovery can be aided nonsurgically by bandaging with an osmotic saline solution. Although a hydrops usually causes increased scarring of the cornea, occasionally it will benefit a patient by creating a flatter cone, aiding the fitting of contact lenses. Corneal transplantation is not usually indicated during corneal hydrops.
Sources: en.wikipedia.org
== Awards == The society sponsors several awards including the Curt Brunnée Award for achievements in instrumentation by a scientist under 45 years of age, the Thomson Medal Award for achievements in mass spectrometry, as well as travel awards and student paper awards:
Hong Kong has two theme parks. Hong Kong Disneyland on Lantau Island is a major theme park and resort destination. Ocean Park Hong Kong combines rides and animal exhibits, with zones across the Waterfront and Summit areas. For big events, Kai Tak Sports Park anchors the city's newest entertainment hub, built on the former airport site, with a 50,000-seat main stadium and a retractable roof. Hong Kong Stadium remains a key venue for football and major fixtures in Causeway Bay, with a capacity of 40,116. AsiaWorld-Expo near the airport hosts concerts, exhibitions, and large-scale conventions across multiple halls and an arena-style space. Hong Kong Convention and Exhibition Centre is the core waterfront venue in Wan Chai for exhibitions, meetings, and shows.
Red yeast rice or red rice koji is a bright reddish purple fermented rice, which acquires its color from being cultivated with the mold Monascus purpureus. Red yeast rice is what is referred to as a kōji in Japanese, meaning "grain or bean overgrown with a mold culture", a food preparation tradition going back to ca. 300 BCE. In addition to its culinary use, red yeast rice is also used in Chinese herbology and Traditional Chinese medicine, possibly during the Tang dynasty around 800 CE. Red yeast rice is described in the Chinese pharmacopoeia Ben Cao Gang Mu by Li Shizhen. Use as a dietary supplement in the modern era developed in the late 1970s, after separate researchers were isolating lovastatin from Aspergillus and monacolins from Monascus, the latter being the type of fungus used to make red yeast rice. Chemical analysis soon showed that lovastatin and monacolin K were identical. Lovastatin became the patented prescription drug Mevacor, and red yeast rice went on to become a non-prescription dietary supplement in the United States and other countries. In 1998, the U.S. Food and Drug Administration (FDA) initiated action to ban dietary supplements containing red yeast rice extract, arguing that red yeast rice products containing monacolin K are identical to a prescription drug, and are thus subject to regulation as a drug.
In June 2020, Health Canada approved the combination for people aged 12 years and older. In September 2021, the provinces Alberta and Saskatchewan announced they will join Ontario in funding the medication. They will determine coverage on a case-by-case basis using criteria that have not yet been announced.
Sources: en.wikipedia.org
Intranasal administration predominates in both animal and human research because it avoids hepatic first-pass metabolism. Injectable and intraperitoneal routes appear in animal work mainly for comparison.
Behavioral endpoints include time spent in open arms of the elevated plus maze and avoidance latencies. Biochemical endpoints include BDNF concentration, cytokine levels, and monoamine metabolite ratios in brain tissue.
Most published studies are small, originate from a limited number of laboratories, and lack independent replication. Dose-response relationships, measured brain exposure, and long-term outcomes are not well characterized.
Reverse-phase HPLC is the usual method and gives a percentage purity value. Mass spectrometry then confirms the molecular mass. Together they provide a basic identity and purity profile for a lot.