The short version of heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
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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.
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.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Free peptide form |
| Molecular mass | About 751.9 Da | Calculated average mass |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form TKPRPGP |
| Structural basis | Tuftsin analogue | Extended version of a natural tetrapeptide |
| Development origin | Russian Academy of Sciences | Work carried out from the 1980s onward |
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.
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 as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
Lyophilized material is generally stable for extended periods when kept dry at or below minus twenty degrees Celsius. Working solutions are less stable, and common practice is to aliquot and freeze them so that repeated freeze-thaw cycles are avoided. Aqueous solutions are sensitive to pH extremes and to microbial growth, so short-term storage at refrigerator temperature is typical. Oxidation and hydrolysis are the principal degradation routes. Reconstitution with sterile water or a mild buffer is standard, and solutions should be protected from light.
Regulatory treatment varies by jurisdiction. In Russia the compound is a registered prescription product, while in the European Union and the United States it is generally handled as a research chemical without a marketing authorization. Suppliers therefore operate outside pharmaceutical oversight, and buyers rely on supplier documentation for purity and identity claims. Chain of custody and third-party testing are the main verification tools. Analysts note that the absence of a pharmacopoeial monograph for research-grade material limits standardization across vendors.
Purity assessment relies mainly on reverse-phase high-performance liquid chromatography with ultraviolet detection. Because the peptide lacks a strong chromophore, detection often uses backbone absorbance near 214 nm. Identity is confirmed by mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, comparing the measured mass against the expected value. Amino acid analysis can verify composition after acid hydrolysis. Diastereomer content and residual counterions are reported less often, although both can influence biological assays.
=== Monoamine oxidase inhibitor === Monoamine oxidase inhibitors, have historically been plagued by questionable efficacy (although early studies used dosages now considered too low) and life-threatening adverse effects. They are still used only rarely, although newer agents of this class (RIMA), with a better side effect profile, have been developed. In older patients TCAs and SSRIs are of the same efficacy. However, there are differences between TCA related antidepressants and classical TCAs in terms of side effect profiles and withdrawal when compared to SSRIs. There is evidence a prominent side-effect of antidepressants, emotional blunting, is confused with a symptom of depression itself. The cited study, according to Professor Linda Gask was:
== Controversies == Al-Fawzan has attracted criticism for a number of public statements and religious opinions. In 2003, he was quoted as saying that "slavery is a part of Islam" and that Muslims who deny this are ignorant and not scholars, comments that drew criticism for contradicting some contemporary interpretations of Islamic law. He has also described public demonstrations as haram, characterizing them as practices of non-Muslims that can lead to division and violence. In 2010, he called for a boycott against Adil al-Kalbani, who had stated that music was not haram (forbidden in Islam). The campaign was a fiasco, as the mosque was overcrowded during Adil al-Kalbani's next sermon. In 2011, opposing the Saudi Ministry of Justice's proposal to set a minimum age for girls' marriage, he reportedly issued a legal opinion authorizing fathers to marry off their daughters "even if they are still in the cradle". In 2014, Saleh al-Fawzan denied reports that he issued a fatwa banning open buffets, clarifying on his website that he had only commented that food of unspecified quantity should not be sold without specification. His statement addressed restaurants where customers pay a fixed price for unspecified portions. In 2015, he was quoted as saying that “Muslims must set aside games and frivolity and take up God’s work. They must not waste their time following games and frivolity, especially not during the blessed month of Ramadan. This is true for Muslims in general, and the younger generation in particular...
== Signs and symptoms == Most individuals with G6PD deficiency are asymptomatic. When it induces hemolysis, the effect is usually short-lived. Most people who develop symptoms are male, due to the X-linked pattern of inheritance, but female carriers can be affected due to unfavorable lyonization or skewed X-inactivation, where random inactivation of an X chromosome in certain cells creates a population of G6PD-deficient red blood cells coexisting with unaffected red blood cells. A female with one affected X chromosome will show the deficiency in approximately half of her red blood cells. However, in some cases, including double X-deficiency, the ratio can be much more than half, making the individual almost as sensitive as males. Red blood cell breakdown (also known as hemolysis) in G6PD deficiency can manifest in many ways, including the following:
50S is the larger subunit of the 70S ribosome of prokaryotes, i.e. bacteria and archaea. It is the site of inhibition for antibiotics such as macrolides, chloramphenicol, clindamycin, and the pleuromutilins. It includes the 5S ribosomal RNA and 23S ribosomal RNA. Despite having the same sedimentation rate, bacterial and archaeal ribosomes can be quite different.
Sources: en.wikipedia.org
The need to recognize sugars is commonly encountered in nature and lectins have independently evolved many times, so that proteins that act as "lectins" come in many structurally distinct folds. The functionality of lectins have also evolved beyond simple recognition: "legume-type" lectins act as toxins to deter predation (with the most famous example being phytohaemagglutinin from legumes) while the separate ricin-type lectin serves to guide the catalytic A chain into victim cells.
In 1893, Prof. Niels Ryberg Finsen (1860–1904) began to treat lupus vulgaris, a tubercular condition of the skin, in the direct mode with heat-filtered light from a carbon arc lamp. He established the Phototherapy treatment at the Whitechapel Hospital in London, which had a Light Department in the first decade of the 20th century. His activity had royal patronage, and Niels Ryberg Finsen received the Nobel Prize in 1903. In 1894, neurologist and psychiatrist Edward Flatau published a human brain atlas, "Atlas of the Human Brain and the Course of the Nerve-Fibres," which consisted of long-exposure photographs of fresh brain sections. It contained an overview of the knowledge of the time on the fibre pathways in the central nervous system. In 1924, the German psychiatrist Hans Berger attached electrodes to the scalp and detected small currents in the brain. In the 1940s, the US War Department investigated the use of electrical stimulation and used so-called "galvanic exercises" on the atrophied hands of patients with ulnar nerve damage from wound surgery, not only to slow and prevent atrophy, but also to restore muscle mass and strength. In the mid-20th century, the scientific study of neuromodulation in humans expanded significantly. Neurologist Professor Spiegel and neurosurgeon Professor Weissys of Temple University presented a stereotactic device to perform "ablation procedures" in humans; in 1947, "intraoperative electrical stimulation" was introduced to test the brain's target zone before surgery.
== Background == A glucose sensitive treatment method for diabetes has long been pursued by researchers since 1979. Such a platform is expected to solve the problem of fluctuations of blood sugar levels. For diabetic patients, skipping a single meal can lead to hypoglycemia, a common complication which can lead to loss of consciousness or seizures. There have been several attempts to create such a medicine, with various levels of success.
Organoselenium chemistry is the science exploring the properties and reactivity of organoselenium compounds, chemical compounds containing carbon-to-selenium chemical bonds. Selenium belongs with oxygen and sulfur to the group 16 elements or chalcogens, and similarities in chemistry are to be expected. Organoselenium compounds are found at trace levels in ambient waters, soils and sediments. Selenium can exist with oxidation state −2, +2, +4, +6. Se(II) is the dominant form in organoselenium chemistry. Down the group 16 column, the bond strength becomes increasingly weaker (234 kJ/mol for the C−Se bond and 272 kJ/mol for the C−S bond) and the bond lengths longer (C−Se 198 pm, C−S 181 pm and C−O 141 pm). Consistent with the inertness of large-n s orbitals, dicoordinate selenium compounds have a bond angle of nearly 90°. Selenium compounds are more nucleophilic than the corresponding sulfur compounds and also more acidic. The pKa values of XH2 are 16 for oxygen, 7 for sulfur and 3.8 for selenium. In contrast to sulfoxides, the corresponding selenoxides are unstable in the presence of β-protons and this property is utilized in many organic reactions of selenium, notably in selenoxide oxidations and in selenoxide eliminations. The first organoselenium compound to be isolated was diethyl selenide in 1836.
Nearly 40,000 workers and harvesters in the provinces of Newfoundland and Labrador applied for the federal relief program TAGS (the Atlantic Groundfish Strategy). Abandoned and rusting fishing boats still litter the coasts of Newfoundland and the Canadian northwest to this day. The fishery minister, John Crosbie, after delivering a speech on the day before the declaration of the moratorium, or July 1, 1992, was publicly heckled and verbally harassed by disgruntled locals at a fishing village. The moratorium, initially lasting for only two years, was indefinitely extended after it became evident that cod populations had not recovered at all but, instead, had continued to spiral downward in both size and numbers, due to the damage caused by decades of destructive fishing practices, and the fact that the moratorium had permitted exceptions for food fisheries for "personal consumption" purposes to this very day. Some 12,000 tons of Northwest cod are still being caught every year along the Newfoundland coast by local fishermen. The collapse of the four-million ton biomass, which had persevered through several previous marine extinctions over tens of millions of years, in a timespan of no more than 20 years, is oft-cited by researchers as one of the most visible examples of the phenomenon of the "Tragedy of the Commons." Factors which had been implicated as contributing to the collapse include: overfishing; government mismanagement; the disregard of scientific uncertainty; warming habitat waters; declining reproduction; and plain human ignorance.
Sources: en.wikipedia.org
== Overview == LLNL is a research and development institution for science and technology applied to national security. Its principal responsibility is ensuring the safety, security and reliability of the nation's nuclear weapons through the application of advanced science, engineering, and technology. The laboratory also applies its special expertise and multidisciplinary capabilities towards preventing the proliferation and use of weapons of mass destruction, bolstering homeland security, and solving other nationally important problems, including energy and environmental needs, scientific research and outreach, and economic competitiveness. The laboratory is located on a 1 square mile (2.6 km2) site at the eastern edge of Livermore. It also operates a 7,000 acres (28 km2) remote experimental test site known as Site 300, situated about 15 miles (24 km) southeast of the main lab site. LLNL has an annual budget of about $3.25 billion and a staff of nearly 10,000 employees.
Troika attempted to equalize the disciplines, keeping the effect intact and normalizing the cost, so a first-level power requires one blood point, a second-level two points, and so on. To balance the clans, the aristocratic Ventrue were only allowed to feed on noble blood, though this was changed to allow them to feed on lower-class humans, receiving less blood. During character creation, the game had an optional character biography with unique positive and negative characteristics (increasing one ability while limiting another). This was removed from the released game; Activision felt there was insufficient test time, and removing it was a more stable option. The team's previous experience was with turn-based combat games, and it struggled to develop a real-time combat system affected by customizable attributes and abilities that provided feedback to the player on how those statistics affected the battle. It initially found that by adhering too closely to the White Wolf source material rules for guns, where the effectiveness of a shot is determined in a contest between the player's skill and the opponent's defense, the firearms seemed broken; the player would not hit where they aimed. Troika found it difficult to mesh the available factors in a real-time setting. Melee combat had to deal with various melee weapons and animations and adjust for melee-on-melee and melee-on-ranged combat. Troika used first-person perspective to immerse the player in the setting, interacting face-to-face with the characters and seeing their facial reactions to the player.
==== Bipolar disorder ==== Pioglitazone has been repurposed as an add-on treatment for depressive episodes in subjects with bipolar disorder. However, meta-analytic evidence is based on very few studies and does not suggest any efficacy of pioglitazone in the treatment of bipolar depression.
==== August 2008 ==== Nezavisimaya Gazeta reported in June 2008 that when Chechen peacekeepers from Vostok Battalion began serving in South Ossetia in the autumn of 2007, they began arresting armed people with fake peacekeeping IDs. However, the Chechens were soon ordered to cease the arrest of the impostors and armed people with unknown affiliations were now freely roaming South Ossetia. On 4 August 2008, Life.ru reported that after the end of the "Kavkaz 2008" exercises, the paratroopers from Pskov remained to occupy the key positions on the Roki and Mamison passes on the border. Several battalions of 58th Army were deployed close to the border and the South Ossetian sources told the newspaper that the deployment of troops began on the night of 2–3 August 2008. Life.ru reported, "The deployment of the Russian military hardware near the Roki Tunnel will allow as soon as possible to move troops to help the peacemaking forces." On 6 August 2008, OsRadio reported that the volunteers were also arriving in Tskhinvali from Moscow. On 26 September 2008, Trud reported on the special battalion Vostok. One member of the battalion Khamzat said, "See what the "Red Star" wrote about us: Volunteers from neighboring republics arrive in South Ossetia. So we are volunteers?!" Khamzat added, "We are the regular subunit of 291-th Regiment of 42nd Guards Motor Rifle Division of the North Caucasus Military District. And we only act on orders." On 8 August 2008, Nezavisimaya Gazeta published an article by journalist who had spent previous three days in Chechnya.
Sources: en.wikipedia.org
It is a seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, produced by chemical synthesis rather than extracted from biological tissue. Its design is based on tuftsin, a natural immunomodulatory tetrapeptide. The C-terminal Pro-Gly-Pro segment is a common stabilising motif in short regulatory peptides.
The core four residues correspond to tuftsin, which occurs naturally as part of immunoglobulin G. The full seven-residue sequence, however, is not a known endogenous peptide. It is a laboratory-designed analogue intended to combine tuftsin-like activity with greater resistance to breakdown.
No single receptor has been confirmed as the primary target. Reports describe involvement of the GABAergic system, interference with enkephalin degradation, and shifts in neurotrophic factor expression. Because these observations come from different models and assays, they have not yet been integrated into one accepted mechanism.
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.