amino acid sequence 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 2026-04-04 and is reviewed periodically as new material appears.
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.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
Quality assessment of Selank samples typically combines purity determination with identity confirmation and counter-ion analysis. Purity is usually reported as a percentage by chromatographic area, with values above 95 percent often quoted for research-grade material. Water content and residual solvents are checked in lyophilized batches because they affect both stability and accurate mass determination. A reported purity figure does not by itself establish that a sample is the intended sequence, so orthogonal methods are needed to rule out sequence isomers or truncation products.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Stabilized analog of tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Monoisotopic mass about 751.9 Da |
| Appearance | White to off-white powder | Typically supplied as lyophilized solid |
| Solubility | Freely soluble in water | Also soluble in common polar solvents |
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
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.
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.
An alternative method used to create ATP is through oxidative phosphorylation, which takes place during cellular respiration. This process utilizes the oxidation of NADH to NAD+, yielding 3 ATP, and of FADH2 to FAD, yielding 2 ATP. The potential energy stored as an electrochemical gradient of protons (H+) across the inner mitochondrial membrane is required to generate ATP from ADP and Pi (inorganic phosphate molecule), a key difference from substrate-level phosphorylation. This gradient is exploited by ATP synthase acting as a pore, allowing H+ from the mitochondrial intermembrane space to move down its electrochemical gradient into the matrix and coupling the release of free energy to ATP synthesis. Conversely, electron transfer provides the energy required to actively pump H+ out of the matrix.
Dawson—who dropped out of Occidental College in December 1965 and remained in Los Angeles for several years thereafter, "hanging out with musicians and weirdos"—had returned to Los Altos Hills by early 1969, allowing him to contribute to the Aoxomoxoa sessions and briefly enroll at Foothill College. After a mescaline experience at Pinnacles National Park with Torbert and Matthew Kelly, he began to compose songs on a regular basis. Some (such as "Glendale Train" and "I Don't Know You") were traditional country pastiches; a number of others ("Last Lonely Eagle", "Garden of Eden", and "Dirty Business") found him working in a "psychedelic country" fusion milieu redolent of Gram Parsons' nascent Flying Burrito Brothers. "Henry", a traditional shuffle with contemporary lyrics about marijuana smuggling, also dates from this period. Dawson's vision was prescient, as 1969 marked the emergence of country rock via Bob Dylan, The Band, The Flying Burrito Brothers, Poco, the Dillard & Clark Band, and the Clarence White-era Byrds. Around this time, Garcia was similarly inspired to take up the pedal steel guitar, and an informal line-up including Dawson, Garcia, and Peninsula folk veteran Peter Grant (on banjo) began playing coffeehouse and hofbrau concerts together when the Grateful Dead were not touring. Their repertoire included country standards, traditional bluegrass, Dawson originals, and a few Dylan covers ("Lay Lady Lay", "You Ain't Goin' Nowhere", "Mighty Quinn").
Dimerization and oligomerization processes have been observed and attributed to several molecular mechanisms, including intermolecular disulfide formation, bridging through metals bound by either Cys or His residues on different MTs, or inorganic phosphate-mediated interactions. Dimeric and polymeric MTs have been shown to acquire novel properties upon metal detoxification, but the physiological significance of these processes has been demonstrated only in the case of prokaryotic Synechococcus SmtA. The MT dimer produced by this organism forms structures similar to zinc fingers and has Zn-regulatory activity. Metallothioneins have diverse metal-binding preferences, which have been associated with functional specificity. As an example, the mouse MT1 preferentially binds divalent metal ions (Zn(II), Cd(II),...), while yeast CUP1 is selective for monovalent metal ions (Cu(I), Ag(I),...). Strictly metal-selective MTs with metal-specific physiological functions were discovered by Dallinger et al. (1997) in pulmonate snails (Gastropoda, Mollusca). The Roman snail (Helix pomatia), for example, possesses a Cd-selective (CdMT) and a Cu-selective isoform (CuMT) involved in Cd detoxification and Cu regulation, respectively. While both isoforms contain unvaried numbers and positions of Cys residues responsible for metal ligation, metal selectivity is apparently achieved by sequence modulation of amino acid residues not directly involved in metal binding (Palacios et al. 2011).
As early as 1960, ZAPU's predecessor, the National Democratic Party (NDP), had established informal contacts with the Soviet Union and Czechoslovakia, and discussed the possibility of obtaining military training in Eastern Europe for its members. In July 1962, Nkomo visited Moscow and discussed plans for a ZAPU-led armed uprising in Rhodesia. He made formal requests for Soviet funding and arms for ZIPRA, explaining that "for these purposes ZAPU needs arms, explosives, revolvers...the party also needs money to bribe persons who guard important installations, to carry out sabotage". The Soviets agreed to supply ZAPU with limited funds beginning in 1963, and increased its level of financial support after UDI. In 1963, ZIPRA also made its first formal request to the Soviet Union for military training. The Soviets began training ZIPRA militants in guerrilla warfare in early 1964. Nkomo's public endorsement of a violent strategy confirmed white politicians' opposition to ZAPU and fed their negative attitudes towards black nationalists at large. In response to the formation of ZIPRA, the Rhodesian government banned ZAPU, driving that party's supporters underground. It also passed draconian security legislation restricting the right to assembly and granting the security forces broad powers to crack down on suspected political subversives. For the first time, the death sentence was also introduced for any act of politically inspired terrorism which involved arson or the use of explosives.
Sources: en.wikipedia.org
Muscle cells work by detecting a flow of electrical impulses from the brain which signals them to contract through the release of calcium by the sarcoplasmic reticulum. Fatigue (reduced ability to generate force) may occur due to the nerve, or within the muscle cells themselves.
== As a sweetener == As miraculin is a readily soluble protein and relatively heat stable, it is a potential sweetener in acidic food, such as soft drinks. While attempts to express it in yeast and tobacco plants have failed, researchers have succeeded in preparing genetically modified E. coli bacteria that express miraculin. Lettuce and tomato have also been used for mass production of miraculin. The use of miraculin as a food additive was denied in 1974 by the United States Food and Drug Administration. However, it can still be sold in the form of whole berries or tablets (as "dietary supplements"). In 2011 the FDA banned a certain brand of miraculin tablets imported from Taiwan as it was thought to be "hard candy" with non-approved sweeteners. Miraculin has a novel food status in the European Union. It is approved in Japan as a safe food additive, according to the List of Existing Food Additives published by the Ministry of Health and Welfare (published by the Japan External Trade Organization).
transactinides Also superheavy elements. In the periodic table, the set of chemical elements with an atomic number greater than 103, i.e. those heavier than the actinides. The transactinides are a subset of the transuranic elements.
Sortases are membrane anchored enzyme that sort these surface proteins onto the bacterial cell surface and anchor them to the peptidoglycan. There are different types of sortases and each catalyse the anchoring of different proteins to cell walls. It is very important for bacteria to acquire iron during infection, Iron is perhaps the most important micronutrient required for bacteria to proliferate and cause disease. Sortase B, is a 246 amino acids polypeptide with putative N-terminal membrane anchor and an active site cysteine located within the TLXTC signature motif of sortases. It appears these enzymes are dedicated to helping the bacteria acquire iron by anchoring iron acquisition proteins to the cell membrane Sortase B recognises and cleaves the NPQTN motif. It links IsDC to mature assemble peptidoglycan, The enzyme catalyses a cell wall sorting reaction in which a surface protein with a sorting signal containing a NXTN motif is cleaved. This enzyme belongs to the peptidase family C60.
== Mechanism == The underlying mechanism involves injury and inflammation of epithelial and sub-epithelial cells. These cells then lose the ability to repair the tissue, in particular they lose the ability to regenerate the epithelial or outermost layer, leading to the excess growth of cells that cause scarring. There are multiple pathways of the disease including fibrotic, lymphocytic, and antibody-mediated that have been described. However, while each pathway has a more unique starting point and cause, the result is still injury and inflammation leading to scarring of the lung tissue. The scarred tissue then makes the expiration phase of respiration more difficult, leading to air not being expelled from the lungs. This is termed "air-trapping", which can be seen on medical imaging. Since the scarring is non-reversible, the disease generally does not improve over time, and depending on the inciting can progress to death.
Sources: en.wikipedia.org
== Side effects == Dihydroergocryptine has been suggested to produce fewer side-effects and have similar efficacy to a classical dopamine agonist due to its biochemical profile. There is also no interference with levodopa metabolism. Although DHEC may come with some acute side-effects described further below, DHEC has overall good tolerability with little to no withdrawal or changes in its scheduling. Acute side-effects usually accompany the beginning of treatment but tend to decrease as the patient develops increased tolerance to the drug. In randomized, double-blinded trials, individuals on different dopamine agonists, including dihydroergocryptine, did not differ in discontinuation rate associated with adverse events. However, there do seem to be a higher incidence of dopaminergic related side-effects such as hallucinations and gastrointestinal complaints tend to be more frequent.
===== Tuberculosis ===== Infants whose mothers have suspected untreated tuberculosis (TB) should be isolated from their mothers to reduce the risk of transmission. As such, these infants should not be breastfed during this time and until the mother has been treated appropriately for 2 weeks and is no longer contagious. However, these infants may be fed expressed breastmilk from their mother. Transmission of TB through breastmilk, without an isolated breast infection caused by the Tuberculosis bacteria (Mycobacterium tuberculosis), has never been documented in the scientific literature. Mothers who do have an isolated breast infection caused by Mycobacterium tuberculosis, termed tuberculous mastitis, should not feed their infants with their own breastmilk, even if it is fed by bottle.
=== Psychological === Early theories of the cause of anorexia linked it to childhood sexual abuse or dysfunctional families; evidence is conflicting, and well-designed research is needed. The fear of food is known as sitiophobia or cibophobia, and is part of the differential diagnosis. Other psychological causes of anorexia include low self-esteem, feeling as if there is lack of control, depression, anxiety, and loneliness. People with anorexia are, in general, highly perfectionistic and most have obsessive compulsive personality traits which may facilitate sticking to a restricted diet. It has been suggested that patients with anorexia are rigid in their thought patterns, and place a high level of importance upon being thin. In the context of anorexia nervosa, this cognitive rigidity refers to the diminished ability to adapt one's behavioral approaches in response to changing circumstances. This weaker cognitive flexibility is a result of neurobiological factors, such as structural differences in prefrontal cortex connectivity, that contribute to the persistence of anorexic behaviors. Although the prevalence rates vary greatly, between 37% and 100%, there appears to be an association between traumatic events and eating disorder diagnosis. Approximately 72% of individuals with anorexia report experiencing a traumatic event prior to the onset of eating disorder symptoms, with binge-purge subtype reporting the highest rates.
==== Eliminated in primary ==== Keith Allen, retail manager Luis Buentello, lobbyist Mayra Flores, former U.S. representative (2022–2023) (previously ran in the 28th district) Gregory Kunkle, musician and candidate for this district in 2022 and 2024
Sources: en.wikipedia.org
Selank is a synthetic heptapeptide designed as a stabilized analog of the natural tetrapeptide tuftsin. It has been investigated mainly for anxiolytic and cognitive effects. It is not an approved pharmaceutical in most countries.
It was developed in Russia, at the Institute of Molecular Genetics of the Russian Academy of Sciences, during the 1990s. Most published research originates from Russian institutions. Independent international replication remains limited.
Tuftsin is a natural tetrapeptide with the sequence Thr-Lys-Pro-Arg that participates in immune signaling. Selank extends that sequence with Pro-Gly-Pro at the C-terminus. The added residues are linked to greater resistance to enzymatic breakdown.
The most common approach combines reverse-phase liquid chromatography with mass spectrometry. Chromatography separates the components while mass spectrometry confirms the molecular mass. Peptide sequencing or tandem mass analysis can further verify the amino acid order.