Enkephalinase comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-04-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Calculated for the free peptide |
| Molecular weight | About 751.9 g/mol | Derived from the sequence |
| Appearance | White to off-white powder | Typical lyophilised form |
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.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
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.
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.
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.
Immediately after the split, William Reid went solo as Lazycame—having already released a solo EP in April 1998—and Jim Reid founded Freeheat along with Lurie and ex-Gun Club bassist Romi Mori and Earl Brutus drummer Nick Sanderson, although neither act received much attention or found any success. In October 2005, it was announced that the Reids were reunited; Jim Reid's track "Song for a Secret" a duet with his wife Julie Barber, was released as a single, paired up with Sister Vanilla's "Can't Stop The Rock", which was written and produced by William and the brothers' younger sibling, Linda. The single was released by Transistor Records on 17 October. Jim promoted his side of the single with a very rare solo gig at London's Sonic Cathedral club on John Peel Day, Thursday 13 October 2005. He finished the appearance with a performance of the early Mary Chain classic "Never Understand". Jim also performed new material at low-key gigs with a new band comprising Phil King on guitar, Loz Colbert (Ride) on drums and bassist Mark Crozer (International Jetsetters). In 2006 five albums were reissued through Rhino Records: Psychocandy, Darklands, Automatic, Honey's Dead and Stoned & Dethroned on 11 July 2006. Each album was released with a DVD containing three promo videos from that particular album.
English is the official language of Belize, a legacy of its former status as a British colony. Belize is the only country in Central America with English as the official language. English is the primary language of public education, government, and most media outlets. Although English is widely used, Belizean Creole is spoken in several situations, whether informal, formal, social, or interethnic dialogue, even in meetings of the House of Representatives. When a creole language exists alongside its lexifier language, as is the case in Belize, a continuum forms between the creole and the lexifier language. Approximately 52.9% of Belizeans self-identify as Mestizo or Hispanic. When Belize was a British colony, Spanish was banned in schools, but since then it has become widely spoken. "Kitchen Spanish" is an intermediate form of Spanish mixed with Belize Creole, spoken in the northern districts. Some good examples are Corozal and San Pedro. Over half the population is multilingual, owing to Belize's status as a small, multiethnic state, surrounded by Spanish-speaking nations. Belize is also home to three Mayan languages: Q'eqchi', Mopan (an endangered language), and Yucatec Maya. Approximately 7,481 people speak the Arawakan-based Garifuna language, and in the mid-1990s about 6,900 Mennonites in Belize spoke Plautdietsch while a minority of Mennonites spoke Pennsylvania Dutch.
== Fragrance == Sandalwood oil is used extensively for its woody-floral scent. Sandalwood oil can also, under certain conditions, have a creamy or even pickled aroma. It pairs well with other wood or floral scents such as violet, rose, tuberose, clove, and oakmoss. But since the wood is so rare and expensive, cosmetic companies use synthetic substitutes of similar structure and scent. There are several synthetic odorants with odor similar to sandalwood oil, used as lower-cost alternatives for perfumes, emollients, and skin cleaning agents. Common synthetic substitutes include Bacdanlol, Brahmanol, Ebanol, Firsantol, Sandalore, and Sandaxol. Two of these, Sandalore and Brahmanol, have been found to be agonists of the cutaneous olfactory receptor OR2AT4, with potential therapeutic benefits for wound healing. Natural sandalwood oil, and other synthetic sandalwood odorants, did not have the same effect.
=== Food tracing systems === The first prize went to Dominique Grégoire from the company TechniGREG who developed new tracing systems: TraciLOG and TraciMEAL. This improved monitoring of the cold chain is a major step forward as far as consumer safety is concerned. The principle is to endow each mobile container with "electronic intelligence", thus enabling it to log each of the phases through which it passes, monitor its internal temperature and record information about whether its doors are open or closed. This information is gathered automatically and securely, without any contact with the contents, and requires no human intervention. It is a reliable global management indicator for use by the logistics service in charge of maintaining the cold chain. Altran engineers worked side by side with the prize-winner, on conducting market studies, on the choice of suppliers, at developing product packaging, on the design of an electronic module and on the transition to the production stage for both TraciLOG and TraciMEAL. After the support, TechniGREG increased its capital of more than 1 million euros. The efforts of these teams were rewarded in March 2001, when a fully operational version of TraciLOG was installed for the first time by a supermarket distributor. TraciMEAL was adopted last May by an institutional food service provider in Toulouse. Since then, TechniGREG, which has registered many patents related to this innovation, has come into business with many companies, particularly in the air transport sector.
Sources: en.wikipedia.org
== Further metabolism == 12-HHT is further metabolized by 15-hydroxyprostaglandin dehydrogenase (NAD+) in a wide variety of human and other vertebrate cells to its 12-oxo (also termed 12-keto) derivative, 12-oxo-5Z,8E,10E-heptadecatrienoic acid (12-oxo-HHT or 12-keto-HHT). Pig kidney tissue also converted 12-HHT to 12-keto-5Z,8E-heptadecadienoic acid (12-oxo-5Z,8E-heptadecadienoic acid) and 12-hydroxy-heptadecadienoic acid. Acidic conditions (pH~1.1–1.5) cause 12-HHT to rearrange in a time- and temperature-dependent process to its 5-cis isomer, 12-hydroxy-5E,8E,10E-heptadecatrienoic acid.
The first use of the term in this sense, to describe the post–World War II geopolitical tensions between the USSR and its satellites and the United States and its western European allies, is attributed to Bernard Baruch, an American financier and presidential advisor. In South Carolina, on April 16, 1947, he delivered a speech (by journalist Herbert Bayard Swope) saying, "Let us not be deceived: we are today in the midst of a cold war." Newspaper reporter-columnist Walter Lippmann gave the term wide currency, with the book Cold War (1947). The term "hot war" is also occasionally used by contrast, but remains rare in literature on military theory. According to academic Covell Meyskens, the term "cold war" was not employed in China during the Maoist era.
A slight majority of Generation Z would like to see fewer instances of romance and sex in the movies and television programs they watch, and more of friendships, platonic love, and other types of relationships, including opposite-sex friendships that do not evolve into romantic or sexual relationships. Pluralities of this cohort also want to see more aromantic or asexual characters. Even so, certain television series such as The Sex Lives of College Girls (2021–2025) and movies like Poor Things (2023) have proven to be popular among younger audiences. A slight majority of Generation Z prefers films and movies with original plots to adaptations, franchises, and remakes. In particular, they would like more contents that are authentic and that reflect their own lives. As members of Generation Z re-watch their favorite childhood films, some have become cult classics for their cohorts, including Charlie and the Chocolate Factory (2005), Star Wars: Episode III – Revenge of the Sith (2005), and Aquamarine (2006). By the mid-2020s, Generation Z has become a key demographic group for movie theaters. As they grow older, members of Generation Z still broadly prefer family-friendly movies, such as the Disney film Lilo & Stitch (2025), and the summer blockbuster Spider-Man: Brand New Day (2026). The animated series Bluey (2018–present), despite being made for preschool children, has captured the imagination of many Millennials and members of Generation Z.
=== Human use === Cobweb paintings, which began during the 16th century in a remote valley of the Austrian Tyrolean Alps, were created on fabrics consisting of layered and wound cobwebs, stretched over cardboard to make a mat, and strengthened by brushing with milk diluted in water. A small brush was then used to apply watercolor to the cobwebs, or custom tools to create engravings. Fewer than a hundred cobweb paintings survive today, most of which are held in private collections. In traditional European medicine, cobwebs were used on wounds and cuts to reduce bleeding and aid healing. This use was recorded in ancient Greece and Rome, and was mentioned in Shakespeare's A Midsummer Night's Dream. Spider webs have been shown to significantly reduce wound healing times. They are rich in vitamin K, which is essential in blood clotting, and their large surface area is also thought to help coagulation. During the 1st century BC, the Roman army used spider webs as field dressings, which also served as a fungicide. The effects of some drugs can be measured by examining their effects on a spider's web-building. In northeastern Nigeria, cow horn resonators in traditional xylophones often have holes covered with spider webs to create a buzzing sound. Spider web strands have been used for crosshairs or reticles in telescopes. Development of technologies to mass-produce spider silk has led to the manufacturing of prototype military protection, wound dressings and other medical devices, and consumer goods. Spider webs can be used as a single step catalyst to make nanoparticles.
The three substrates of this enzyme are L-aspartic acid, water, and oxidised nicotinamide adenine dinucleotide (NAD+}. Its products are oxaloacetic acid, ammonia, reduced NADH, and a proton. Nicotinamide adenine dinucleotide phosphate can be used as an alternative cofactor. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH2 group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is L-aspartate:NAD(P)+ oxidoreductase (deaminating). Other names in common use include NAD-dependent aspartate dehydrogenase, NADH2-dependent aspartate dehydrogenase, and NADP+-dependent aspartate dehydrogenase. This enzyme participates in nicotinate and nicotinamide metabolism.
Sources: en.wikipedia.org
Social activities termed "organic work" consisted of self-help organizations that promoted economic advancement and work on improving the competitiveness of Polish-owned businesses, industrial, agricultural or other. New commercial methods of generating higher productivity were discussed and implemented through trade associations and special interest groups, while Polish banking and cooperative financial institutions made the necessary business loans available. The other major area of effort in organic work was educational and intellectual development of the common people. Many libraries and reading rooms were established in small towns and villages, and numerous printed periodicals manifested the growing interest in popular education. Scientific and educational societies were active in a number of cities. Such activities were most pronounced in the Prussian Partition. Positivism in Poland replaced Romanticism as the leading intellectual, social and literary trend. It reflected the ideals and values of the emerging urban bourgeoisie. Around 1890, the urban classes gradually abandoned the positivist ideas and came under the influence of modern pan-European nationalism.
Along with the international protection, Mexico has also sought similar protection for tequila in other important countries and regions through a number of bilateral and multilateral agreements. Pursuant to Annex 313 of the North American Free Trade Agreement (NAFTA), Canada and the United States recognize tequila and mezcal as products originating from Mexico and, consequently, do not permit the sale of any product as tequila and/or mezcal unless they have been lawfully prepared in Mexico. The Mexican government enforces the tequila intellectual property through the Mexican Institute of Industrial Property (IMPI). The use of the name tequila is authorized and administered only by IMPI. IMPI may prohibit any unauthorized use of the name that may create confusion for the consumers, or constitute an act of unfair competition. Despite protection under the Lisbon Agreement and NAFTA, tequila still faced competition from some pseudo tequilas. During the mid-1990s, as much as 3.5 million liters of these liquors were sold annually in Europe. The European liquors were produced from sugars of agave-like plants and were illegally labeled as tequila. Following the NAFTA precedent, Mexico entered into a bilateral agreement with the European Union concerning the mutual recognition and protection of AO in the spirits sector. Under this agreement the EU recognizes tequila and mezcal as "denominations of origin", although enforcement has still been quite lax in Europe.
musculoskeletal pain neck pain muscle spasms extremity pain muscle fatigue anaphylaxis malignancy The most common adverse effect of reslizumab was oropharyngeal (mouth and throat) pain. According to the phase III clinical trials data, oropharyngeal pain occurred in ≥2% of individuals along with elevated baseline creatine phosphokinase (CPK), which was more common in patients treated with reslizumab versus placebo. Myalgia was also reported more in patients in the reslizumab 3 mg/kg group versus the placebo group as well as some musculoskeletal adverse reactions. Lastly, some serious adverse reactions that occurred in subjects treated with reslizumab but not in those treated with placebo included anaphylaxis and malignancy.
==== Conceptual history ==== The third season episode "Piper Maru" marked the first occurrence of the black oil. The on-screen appearance of the substance was achieved through visual effects, with the shimmering oil effect being digitally placed over the actors' corneas in post-production. The crew went through various iterations to find the two "right" types of fluids. According to physical effects crewman David Gauthier, they used a mix of oil and acetone, which he believed gave the substance a more globular look. Special effects technician Mat Beck was able to digitally bend the oil effect around the shape of the actors' eyes. The season eight episode, "Vienen", marked the last appearance of the black oil in the series. Molasses and chocolate syrup were used for the visual effects of the black oil. The scene with the black oil coming out of the eyes, ears and mouth was mostly done on a visual effects stage. Due to the uncontrollable nature of the substance, it took nine takes to get the syrup to spill on the right places.
Sources: en.wikipedia.org
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, commonly written as TKPRPGP. It shares the first four residues with tuftsin and carries three prolines in the chain. The proline-rich tail is the main structural feature that separates it from the parent tetrapeptide.
Selank is a synthetic analogue built on the tuftsin tetrapeptide Thr-Lys-Pro-Arg. Extra proline residues were added to the C-terminus during design work. That modification is intended to make the peptide less vulnerable to rapid enzymatic degradation.
Transliteration from Russian produces variant spellings such as Selanc. Many suppliers avoid the trade-style name entirely and list the peptide sequence. Comparing sequences rather than names is the reliable way to confirm two entries describe the same molecule.
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.