Tuftsin analogue is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2025-09-26. Numbers and descriptions here follow the published literature rather than marketing material.
Once dissolved, the peptide is markedly less stable than the dry powder. Aqueous solutions are subject to backbone hydrolysis and to microbial growth when they are handled without sterile technique. Buffered solutions near neutral pH are common for short-term laboratory work, while acidic conditions are sometimes used to improve solubility. Analytical laboratories generally prepare working solutions fresh rather than storing them, and a residual water film left in a reopened vial can seed degradation even when the container appears dry.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity specification | 95 percent or higher by RP-HPLC | Area percentage of the main peak |
| Identity confirmation | Electrospray ionization mass spectrometry | Observed mass compared with the theoretical value near 751.9 Da |
| Recommended dry storage | -20 °C, desiccated | -80 °C for multi-year archival material |
| Solution handling | Prepare fresh; avoid long storage | Sterile filtration reduces microbial load |
| Common synonyms | TKPRPGP; TP-7 | Sequence code and laboratory designation used interchangeably |
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.
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.
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.
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.
=== Interaction with cellular proteins === Localization of CK1δ to certain subcellular compartments can furthermore be initiated by its interaction with cellular proteins. In order to mediate interaction with CK1δ appropriate docking motifs need to be present in the respective proteins. Docking motif Phe-X-X-X-Phe has been identified in NFAT, β-catenin, PER, and proteins of the FAM83 family. As an example, nuclear CK1δ can be localized to nuclear speckles by its interaction with FAM83H. Another interaction motif is represented by the sequence Ser-Gln-Ile-Pro, which is present in microtubule plus-end-binding protein 1 (EB1). Numerous interaction partners for CK1δ have been described within recent years, forming strong interactions with CK1δ and therefore being more than simple substrate proteins. As mentioned above, interactions with CK1δ have been shown for AKAP450 and DDX3X. By initially performing yeast two-hybrid screens, interaction could also be confirmed for the Ran-binding protein in the microtubule-organizing center (RanBPM), microtubule-associated protein 1A, and snapin, a protein associated with neurotransmitter release in neuronal cells. Interactions with CK1δ have also been detected for the development-associated factors LEF-1 (lymphocyte enhancer factor-1) and the proneural basic helix-loop-helix (bHLH) transcription factor Atoh1. Finally, interaction of CK1δ with PER and CRY circadian clock proteins have been demonstrated, facilitating nuclear translocation of PERs and CRYs.
=== Breast changes === Spironolactone can cause breast pain and enlargement in women. This is "probably because of estrogenic effects on target tissue." At low doses, breast tenderness has been reported in only 5% of women, but at high doses, it has been reported in up to 40% of women. Breast enlargement and tenderness may occur in 26% of women at high doses. Some women regard spironolactone-induced breast enlargement as a positive effect. Spironolactone also commonly and dose-dependently produces gynecomastia (breast development) as a side effect in men. At low doses, the rate is only 5 to 10%, but at high doses, up to or exceeding 50% of men may develop gynecomastia. In the RALES, 9.1% of men taking 25 mg/day spironolactone developed gynecomastia, compared to 1.3% of controls. Conversely, in studies of healthy men given high-dose spironolactone, gynecomastia occurred in 3 of 10 (30%) at 100 mg/day, in 5 of 8 (62.5%) at 200 mg/day, and in 6 of 9 (66.7%) at 400 mg/day, relative to none of 12 controls. The severity of gynecomastia with spironolactone varies considerably, but is usually mild. As with breast enlargement caused by spironolactone in women, gynecomastia due to spironolactone in men is often, although inconsistently, accompanied by breast tenderness. In the RALES, only 1.7% of men developed breast pain, relative to 0.1% of controls. The time to onset of spironolactone-induced gynecomastia has been found to be 27 ± 20 months at low doses and 9 ± 12 months at high doses.
Transamination is mediated by several types of aminotransferase enzymes. An aminotransferase may be specific for an individual amino acid, or it may be able to process any member of a group of similar ones, for example the branched-chain amino acids, which comprises valine, isoleucine, and leucine. The two common types of aminotransferases are alanine aminotransferase (ALT) and aspartate aminotransferase (AST).
Sources: en.wikipedia.org
== History == The FODMAP concept was first published in 2005. In this paper, it was proposed that a collective reduction in the dietary intake of all indigestible or slowly absorbed, short-chain carbohydrates would minimize stretching of the intestinal wall. This was proposed to reduce stimulation of the gut's nervous system and provide the best chance of reducing symptom generation in people with IBS (see below). At the time, there was no collective term for indigestible or slowly absorbed, short-chain carbohydrates, so the term FODMAP was created to improve understanding and facilitate communication of the concept. The low-FODMAP diet was originally developed by a research team at Monash University in Melbourne, Australia. The Monash team undertook the first research to investigate whether a low-FODMAP diet improved symptom control in patients with IBS and established the mechanism by which the diet exerted its effect. Monash University also established a rigorous food analysis program to measure the FODMAP content of a wide selection of Australian and international foods. The FODMAP composition data generated by Monash University updated previous data that was based on limited literature, with guesses (sometimes wrong) made where there was little information.
The continued influx of foreign players at Arsenal has, however, attracted criticism. In a league match against Crystal Palace on 14 February 2005, Arsenal fielded a 16-man squad that featured no British players for the first time in the club's history. This prompted Professional Footballers' Association (PFA) chief executive Gordon Taylor to express it would begin "a worrying pattern for English football". A year later, manager Alan Pardew commented that Arsenal's Champions League success was "not necessarily a triumph for British football". Wenger saw the issue of nationality as irrelevant and said, "When you represent a club, it's about values and qualities, not about passports". Other pundits including Trevor Brooking, the director of football development at the FA, have defended Wenger. Brooking has stated that a lack of English players in "one of England's most successful clubs" was more of a reflection on England's limited talent pool rather than on Wenger, an opinion shared by youth-team coach and former Liverpool player Craig Johnston. Several English players have started their careers at Arsenal under Wenger, such as Ashley Cole, David Bentley and Matthew Upson, Wenger commented that an advantage of building his team around British players was the guarantee of stability.
Islam is the largest religion in Ningxia, adhered to by 34% of the population according to a 2010 survey. Many of the Han Chinese practise Chinese folk religions, Taoism, Confucianism and Chinese Buddhism. Christianity was the religion of 1.17% of the province's population according to the Chinese General Social Survey of 2004. In 2008, there were 3,760 mosques in Ningxia, which is about one per 1730 residents.
==== 4.D Polysaccharide Synthase/Exporters ==== 4.D.1 The Putative Vectorial Glycosyl Polymerization (VGP) Family 4.D.2 The Glycosyl Transferase 2 (GT2) Family 4.D.3 The Glycan Glucosyl Transferase (OpgH) Family
Sources: en.wikipedia.org
== Crystal structure == More than six crystalline forms of aluminum sulfide are known and only some are listed below. Most of them have rather similar, wurtzite-like structures, and differ by the arrangement of lattice vacancies, which form ordered or disordered sublattices.
== Education and training == Initial glance, forensic intelligence may appear as a nascent facet of forensic science facilitated by advancements in information technologies such as computers, databases, and data-flow management software. However, a more profound examination reveals that forensic intelligence represents a genuine and emerging inclination among forensic practitioners to actively participate in investigative and policing strategies. In doing so, it elucidates existing practices within scientific literature, advocating for a paradigm shift from the prevailing conception of forensic science as a conglomerate of disciplines merely aiding the criminal justice system. Instead, it urges a perspective that views forensic science as a discipline studying the informative potential of traces—remnants of criminal activity. Embracing this transformative shift poses a significant challenge for education, necessitating a shift in learners' mindset to accept concepts and methodologies in forensic intelligence. Recent calls advocating for the integration of forensic scientists into the criminal justice system, as well as policing and intelligence missions, underscore the necessity for the establishment of educational and training initiatives in the field of forensic intelligence. This article contends that a discernible gap exists between the perceived and actual comprehension of forensic intelligence among law enforcement and forensic science managers, positing that this asymmetry can be rectified only through educational interventions.
== Mechanism of action == Didanosine (ddI) is a nucleoside analogue of adenosine. It differs from other nucleoside analogues, because it does not have any of the regular bases, instead it has hypoxanthine attached to the sugar ring. Within the cell, ddI is phosphorylated to the active metabolite of dideoxyadenosine triphosphate, ddATP, by cellular enzymes. Like other anti-HIV nucleoside analogs, it acts as a chain terminator by incorporation and inhibits viral reverse transcriptase by competing with natural dATP.
=== ATLAS and P-body === ATLAS and P-body (known as Blue and Orange to GLaDOS) are player characters in the co-op campaign of Portal 2. They are two robots that cannot speak and can only produce grunts, which are voiced by Dee Bradley Baker. They are equipped with their own portal guns which bears the colour of its user (blue and purple for ATLAS, yellow and red for P-body). Atlas and P-Body are described as masculine and feminine, respectively, as stated by Chet Faliszek in an interview. During the campaign, GLaDOS calls them Blue and Orange, respectively, and constantly tries to ruin their relationship by awarding one and ignoring the other. GLaDOS sends ATLAS and P-body into four areas to access data discs. Once done, they are blown up, as GLaDOS claims it is the only way they can be retrieved from these areas. Later, GLaDOS commands them to retrieve a certain "surprise" in an area. They go in search, only to find hundreds of thousands of other test subjects in suspended animation. After the co-op campaign is finished, GLaDOS quotes that they saved science. ATLAS and P-body begin to celebrate, only to be promptly blown up by GLaDOS. In the DLC campaign "Peer Review", ATLAS and P-body are reactivated by GLaDOS one week after the original co-op campaign, during which GLaDOS has already wiped out all of the found test subjects in her attempts to turn them into "killing machines". The two robots are sent to find a saboteur that has taken control of a prototype central core and is causing problems in the facility.
== Research == SGLT2 inhibitors increase circulating ketone body concentrations. The cardioprotective effects of SGLT2 inhibitors have been attributed to the elevated ketone levels. Gliflozins have been posited to exhibit protective effects on the heart, liver, kidneys, anti‐hyperlipidemic, anti‐atherosclerotic, anti‐obesity, anti‐neoplastic effects in in vitro, pre‐clinical, and clinical studies. Pleiotropic effects of this class have been attributed to a variety of its pharmacodynamic actions such as natriuresis, hemoconcentration, deactivation of renin–angiotensin–aldosterone system, ketone body formation, alterations in energy homeostasis, glycosuria, lipolysis, anti‐inflammatory, and antioxidative actions. SGLT2 inhibitors have shown beneficial effects on liver function in clinical trials on individuals with NAFLD and type 2 diabetes, and also on those without type 2 diabetes. SGLT2 inhibitors also modified the adverse effects of ozone in heart failure, indicating a potential cardioprotective role. SGLT2 inhibitors have anti-inflammatory and immunomodulatory effects through pathways such as NF-κB, AMPK/mTOR, and JAK/STAT.
Sources: en.wikipedia.org
Sealed, desiccated storage at -20 °C or colder is the standard recommendation for research-grade material. Vials should reach room temperature before they are opened, which limits condensation. Repeated temperature cycling is discouraged.
A reported purity value reflects the share of the main peak in one chromatographic run and says nothing about identity. Confirming that the expected sequence is present requires a separate measurement such as mass spectrometry. Purity and identity are distinct questions.
A mass spectrum reports the molecular masses present in a sample and shows whether they match the value expected for selank, near 751.9 Da. It also flags common artifacts such as truncation or adduct formation. It does not establish correct stereochemistry or complete sequence order on its own.
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.