The short version of Tuftsin analogue fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-10-10. Anything still debated is marked as such rather than presented as settled.
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.
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.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Derived from the seven-residue sequence |
| Molecular weight | About 751.9 g/mol | Average mass; the monoisotopic value is slightly lower |
| Residue count | Seven amino acids | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Parent compound | Tuftsin (Thr-Lys-Pro-Arg) | Selank extends tuftsin at the C-terminus |
| Compound class | Synthetic short peptide | Studied in a research setting; not a licensed drug in most markets |
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.
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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter notation. Its structure consists of the immunomodulatory tetrapeptide tuftsin, Thr-Lys-Pro-Arg, extended at the carboxyl terminus by a Pro-Gly-Pro segment. The molecular formula is commonly given as C33H57N11O9, corresponding to a monoisotopic mass near 751.4 Da and an average molecular mass near 751.9 Da. All seven residues are proteinogenic amino acids, and the molecule carries no modified side chains or non-natural linkages.
The compound was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences during the 1980s and 1990s. The stated design goal was to retain the immunomodulatory and central nervous system activity attributed to tuftsin while improving resistance to enzymatic breakdown. Adding a proline-rich tail to the short parent peptide was a deliberate strategy, because proline residues restrict the conformations available to many peptidases. The same laboratory produced Semax, an ACTH fragment analog, and both compounds were developed in parallel as short, enzymatically stabilized peptides intended for intranasal use.
After returning from the DL, Helton played only 6 games before announcing that he would have season-ending hip surgery in order to prepare for the 2013 season. Helton was healthier in 2013, playing in 124 games, while hitting 15 home runs with 61 RBIs. On September 14, 2013, Helton announced that he would be retiring at the conclusion of the 2013 season. On September 25, before his last game at Coors Field, Helton was honored by the Rockies in a pre-game ceremony. In the game, Helton hit a home run and drove in three runs versus the Boston Red Sox. On August 17, 2014, the Rockies retired Helton's number 17 before a game at Coors Field. He was the first Rockies player to have his number retired in the franchise's history.
The new 37th district is based in all but the westernmost parts of Austin, with virtually all of the precincts of the exclusively Travis County-based district favoring Democrats to varying degrees; the new district has a White plurality with a 34% Hispanic voting age population. The incumbent is Democrat Lloyd Doggett, who was re-elected with 75.9% of the vote in 2024. On August 21, 2025, Doggett announced that he would not seek re-election due to mid-decade redistricting, and fellow Democratic Rep. Greg Casar being moved into the 37th district. On August 25, 2025, Casar announced his bid for re-election from this district. Kamala Harris won 76.8% of the vote in the new 37th District, which also gave 79.2% of the vote to Colin Allred; in both cases, the highest of any district amongst the state's new congressional districts.
The loose connective tissue plugs occupying the alveolar spaces often connect to other connective tissue plugs in nearby alveoli via the pores of Kohn creating a characteristic butterfly pattern on histology. There is usually minimal to no interstitial inflammatory changes in biopsies of organizing pneumonia.
== References == Hunter, R. L.; Merkert, C.L. (1957). "Histochemical demonstration of enzymes separated by zone electrophoresis in starch gels". Science. 125 (3261): 1294–1295. doi:10.1126/science.125.3261.1294-a. PMID 13432800. Weiss, B.; Hait, W.N. (1977). "Selective cyclic nucleotide phosphodiesterase inhibitors as potential therapeutic agents". Annu. Rev. Pharmacol. Toxicol. 17: 441–477. doi:10.1146/annurev.pa.17.040177.002301. PMID 17360. Wendel, JF, and NF Weeden. 1990. "Visualisation and interpretation of plant isozymes." pp. 5–45 in D. E. Soltis and P. S. Soltis, eds. Isozymes in plant biology. Chapman and Hall, London. Weeden, NF, and JF Wendel. 1990. "Genetics of plant isozymes". pp. 46–72 in D. E. Soltis and P. S. Soltis, eds. Isozymes in plant biology. Chapman and Hall, London Crawford, DJ. 1989. "Enzyme electrophoresis and plant systematics". pp. 146–164 in D. E. Soltis and P. S. Soltis, eds. Isozymes in plant biology. Dioscorides, Portland, Oregon. Hamrick, JL, and MJW Godt. 1990. "Allozyme diversity in plant species". pp. 43–63 in A. H. D. Brown, M. T. Clegg, A. L. Kahler and B. S. Weir, eds. Plant Population Genetics, Breeding, and Genetic Resources. Sinauer, Sunderland Biochemistry by jeremy M. Berg, John L. Tymoczko, Lubert Stryer (Intro taken from this textbook) Specific
== Manufacturing == Industrial production of cottage cheese relies on two primary methodologies: the traditional cultured method and the direct acid-set method. The global adoption of these processes varies by region due to local clean-label food regulations, factory scales, and consumer flavour preferences. Both processes begin with pasteurised skimmed milk, concentrated non-fat milk, or reconstituted non-fat dry milk to control baseline protein ratios.
Sources: en.wikipedia.org
==== Celanese synthesis ==== An alternative industrial synthesis developed at Celanese involves firstly direct acylation of phenol with acetic anhydride in the presence of hydrogen fluoride to give a methyl ketone, then the conversion of the ketone with hydroxylamine to a ketoxime, and finally the acid-catalysed Beckmann rearrangement of the oxime to the amide in the para-acetylaminophenol product.
Ribosomes are classified as being either "free" or "membrane-bound". Free and membrane-bound ribosomes differ only in their spatial distribution; they are identical in structure. Whether the ribosome exists in a free or membrane-bound state depends on the presence of an ER-targeting signal sequence on the protein being synthesized, so an individual ribosome might be membrane-bound when it is making one protein, but free in the cytosol when it makes another protein. Ribosomes are sometimes referred to as organelles, but the use of the term organelle is often restricted to describing sub-cellular components that include a phospholipid membrane, which ribosomes, being entirely particulate, do not. For this reason, ribosomes may sometimes be described as "non-membranous organelles".
Slavery existed in ancient China as early as the Shang dynasty. Slavery was employed largely by governments as a means of maintaining a public labour force. After the Southern and Northern Dynasties, due to years of poor harvests, the influx of foreign tribes, and the resulting wars, the number of slaves exploded. They became a class and were called "jianmin (Chinese: 贱民)" (literally "inferior person"). As stated in The commentary of Tang Code: "Slaves and inferior people are legally equivalent to livestock products". They always had a low social status, and even if they were deliberately murdered, the perpetrators received only a year in prison, and were punished even when they reported the crimes of their lords. However, in the later period of the dynasty, perhaps because the increase in the number of slaves slowed down again, the penalties for crimes against them became harsh again. For example, the famous contemporary female poet Yu Xuanji was publicly executed for murdering her own slave. Many Han Chinese were enslaved in the process of the Mongol invasion of China proper. According to Japanese historians Sugiyama Masaaki (杉山正明) and Funada Yoshiyuki (舩田善之), Mongolian slaves were owned by Han Chinese during the Yuan dynasty. Slavery has taken various forms throughout China's history. It was reportedly abolished as a legally recognized institution, including in a 1909 law fully enacted in 1910, although the practice continued until at least 1949.
== Child drownings == As of 2020, Thailand leads ASEAN in child drownings and its death rate for drowning by children less than 15 years of age is twice the world average. From 2000 to 2018, there were more than 22,700 drowned children, averaging about 1,262 children per year or five per day. Drownings are decreasing—in 2018, 727 children drowned, down from 1,244 a decade earlier. Most drownings occur around the time of the Songkran holiday.
The surgeon replaces missing parts with tissue of like quality and quantity; nasal lining with mucosa, cartilage with cartilage, bone with bone, and skin with skin that best match the native skin color and skin texture of the damaged nasal subunit. For such surgical repairs, skin flaps are preferable to skin grafts, because skin flaps generally are the superior remedy for matching the color and the texture of nasal skin, better resist tissue contracture, and provide better vascularisation of the nasal skeleton; thus, when there is sufficient skin to allow tissue harvesting, nasal skin is the best source of nasal skin. Furthermore, despite its notable scarring propensity, the nasal skin flap is the prime consideration for nasal reconstruction, because of its greater verisimilitude. The most effective nasal reconstruction for repairing a defect (wound) of the nasal skin, is to re-create the entire nasal subunit; thus, the wound is enlarged to comprehend the entire nasal subunit. Technically, this surgical principle permits laying the scars in the topographic transition zone(s) between and among adjacent aesthetic subunits, which avoids juxtaposing two different types of skin in the same aesthetic subunit, where the differences of color and texture might prove too noticeable, even when reconstructing a nose with skin flaps. Nonetheless, in the final stage of nasal reconstruction—replicating the "normal nose" anatomy by subcutaneous sculpting, the surgeon does have technical allowance to revise the scars, and render them (more) inconspicuous.
Sources: en.wikipedia.org
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.
Tuftsin contains four residues, while selank carries an additional Pro-Gly-Pro segment at the carboxyl end. That extension is intended to reduce enzymatic cleavage. Comparative pharmacokinetic data in humans remain limited.
No single receptor target is widely accepted as the definitive mediator of the reported effects. Proposed contributors include GABAergic modulation, shifts in monoamine turnover, and altered neuropeptide degradation. The mechanism is treated in the literature as unresolved.
Dry powder is normally held at -20 degrees Celsius or below in a sealed, light-protected container with desiccant. Brief room-temperature handling during weighing is generally tolerated. Storage instructions vary between suppliers, so the accompanying certificate of analysis should be followed.