This is a working overview of tuftsin, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-08-30 and is reviewed periodically as new material appears.
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 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 bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
| 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 |
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.
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.
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.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
Prolactin-releasing hormone, also known as PRLH, is a hypothetical human hormone or hormone releasing factor. Existence of this factor has been hypothesized as prolactin is the only currently known hormone for which almost exclusively negative regulating factors are known (such as dopamine, leukemia inhibitory factor, some prostaglandins) but few stimulating factor. Its secretion is mediated by estrogen from placenta during pregnancy to elevate blood level of prolactin. While many prolactin stimulating and enhancing factors are well known (such as thyrotropin-releasing hormone, oxytocin, vasoactive intestinal peptide and estrogen) those have primary functions other than stimulating prolactin release and the search for hypothetical releasing factor or factors continues. The prolactin-releasing peptide identified in 1998 was a candidate for this function, however as of 2008 it appears its function is not yet completely elucidated.
The President believed that a pro-American China would be useful for the United States should the Americans, Soviets, and Chinese agree to jointly occupy Japan and Korea after the war. When Molotov voiced concerns about the stability of China, Roosevelt responded by saying that the combined "population of our nations and friends was well over a billion people". Roosevelt also believed China was the only Asian nation strong enough to be one of the Policemen (as Japan could not be included due to being an Axis member) and this was necessary to help avoid dividing his vision of a new global order along racial lines (Roosevelt also viewed the inclusion of what he saw as the "part-Asian" Soviets as important for the same reason). Churchill objected to Roosevelt's inclusion of China as one of the Big Four because he feared that the Americans were trying to undermine Britain's colonial holdings in Asia. In October 1942, Churchill told Eden that Republican China represented a "faggot vote on the side of the United States in any attempt to liquidate the British overseas empire." Eden shared this view with Churchill and expressed skepticism that China, which was then in the midst of a civil war, could ever return to a stable nation. Roosevelt responded to Churchill's criticism by telling Eden that "China might become a very useful power in the Far East to help police Japan" and that he was fully supportive of offering more aid to China.
Copper(II) sulfate is an inorganic compound with the chemical formula CuSO4. It forms hydrates CuSO4·nH2O, where n can range from 1 to 7. The pentahydrate (n = 5), a bright blue crystal, is the most commonly encountered hydrate of copper(II) sulfate, while its anhydrous form is white. Older names for the pentahydrate include blue vitriol, bluestone, vitriol of copper, and Roman vitriol. It exothermically dissolves in water to give the aquo complex [Cu(H2O)6]2+, which has octahedral molecular geometry. The structure of the solid pentahydrate reveals a polymeric structure wherein copper is again octahedral but bound to four water ligands. The Cu(II)(H2O)4 centers are interconnected by sulfate anions to form chains.
At least five artists have made explicit reference to the α-helix in their work: Julie Newdoll in painting and Julian Voss-Andreae, Bathsheba Grossman, Byron Rubin, and Mike Tyka in sculpture. San Francisco area artist Julie Newdoll, who holds a degree in microbiology with a minor in art, has specialized in paintings inspired by microscopic images and molecules since 1990. Her painting "Rise of the Alpha Helix" (2003) features human figures arranged in an α helical arrangement. According to the artist, "the flowers reflect the various types of sidechains that each amino acid holds out to the world". This same metaphor is also echoed from the scientist's side: "β sheets do not show a stiff repetitious regularity but flow in graceful, twisting curves, and even the α-helix is regular more in the manner of a flower stem, whose branching nodes show the influence of environment, developmental history, and the evolution of each part to match its own idiosyncratic function." Julian Voss-Andreae is a German-born sculptor with degrees in experimental physics and sculpture. Since 2001 Voss-Andreae creates "protein sculptures" based on protein structure with the α-helix being one of his preferred objects. Voss-Andreae has made α-helix sculptures from diverse materials including bamboo and whole trees. A monument Voss-Andreae created in 2004 to celebrate the memory of Linus Pauling, the discoverer of the α-helix, is fashioned from a large steel beam rearranged in the structure of the α-helix.
Sources: en.wikipedia.org
=== Early developments === The first cold breakfast cereal, Granula, was invented in the United States in 1863 by James Caleb Jackson, operator of Our Home on the Hillside which was later replaced by the Jackson Sanatorium in Dansville, New York. The cereal never became popular, due to the inconvenient necessity of tenderizing the heavy bran and graham nuggets by soaking them overnight. George H. Hoyt created Wheatena circa 1879, during an era when retailers would typically buy cereal (the most popular being cracked wheat, oatmeal, and cerealine) in barrel lots, and scoop it out to sell by the pound to customers. Hoyt, who had found a distinctive process of preparing wheat for cereal, sold his cereal in boxes, offering consumers a more sanitary and consumer-friendly option.
Ribonucleoprotein Networks Analyzed by Mutational Profiling (RNP-MaP) is a strategy for probing RNA-protein networks and protein binding sites at a nucleotide resolution. Information about RNP assembly and function can facilitate a better understanding of biological mechanisms. RNP-MaP uses NHS-diazirine (SDA), a hetero-bifunctional crosslinker, to freeze RNA-bound proteins in place. Once the RNA-protein crosslinks are formed, MaP reverse transcription is then conducted to reversely transcribe the protein-bound RNAs as well as introduce mutations at the site of RNA-protein crosslinks. Sequencing results of the cDNAs reveal information about both protein-RNA interaction networks and protein binding sites.
Mary Osborn (born in 1940) is a L'Oréal-UNESCO Women in Science Award-winning English cell biologist who, until she stopped running an active laboratory in 2005, was on the scientific staff at the Max Planck Institute for Biophysical Chemistry, Göttingen, Germany. Osborn established two techniques frequently used by cell biologists. She pioneered both molecular weight determination of proteins using SDS PAGE and immunofluorescence microscopy. Osborn also used the immunofluorescence microscopy method to work out the details of the eukaryotic cytoskeleton. Small differences in the intermediate filament constituents helped her distinguish differentiated cells from each other. She also found intermediate filament immunofluorescence differences between normal versus cancer cells. Mary Osborn has been a prominent spokesperson for women in science.
In the periodic table, mendelevium is located to the right of the actinide fermium, to the left of the actinide nobelium, and below the lanthanide thulium. Mendelevium metal has not yet been prepared in bulk quantities, and bulk preparation is currently impossible. Nevertheless, a number of predictions and some preliminary experimental results have been done regarding its properties. The lanthanides and actinides, in the metallic state, can exist as either divalent (such as europium and ytterbium) or trivalent (most other lanthanides) metals. The former have fns2 configurations, whereas the latter have fn−1d1s2 configurations. In 1975, Johansson and Rosengren examined the measured and predicted values for the cohesive energies (enthalpies of crystallization) of the metallic lanthanides and actinides, both as divalent and trivalent metals. The conclusion was that the increased binding energy of the [Rn]5f126d17s2 configuration over the [Rn]5f137s2 configuration for mendelevium was not enough to compensate for the energy needed to promote one 5f electron to 6d, as is true also for the very late actinides: thus einsteinium, fermium, mendelevium, and nobelium were expected to be divalent metals. The increasing predominance of the divalent state well before the actinide series concludes is attributed to the relativistic stabilization of the 5f electrons, which increases with increasing atomic number. Thermochromatographic studies with trace quantities of mendelevium by Zvara and Hübener from 1976 to 1982 confirmed this prediction.
Deputy Director of Adult Social Care, Care Quality Commission. For services to Adult Social Care. Dr. Meenakshi Nagpaul (Meena Thakur). General Practitioner, Honeypot Medical Centre and Clinical Director, Harrow East Primary Care Network. For services to the NHS. Jacqueline Neilson. Chief Executive Officer, Rain Rescue. For services to Animal Welfare. William Lambton Nicholson. Leader, Newbury Working Party Group. For services to Canal Restoration. June Edna Nicol-Dundas. Foster Carer, Fostering London. For services to Young People. Christopher Mansfeldt Norman. Chief Executive and Founder, GOOD Agency. For services to the Business and Charitable Sectors. John Norris. Chair, B&M Longworth (Edgworth) Ltd. For services to Innovation, to Sustainability and to International Trade. Lawrence John O'Halleron. Chair, Big Local Gateshead. For services to the community in Gateshead, Tyne and Wear. Leona O'Neil. Founder, The Boom Foundation. For services to Charitable Fundraising for People with Sarcoma. Harry Clive O'Neill. For charitable services to the community in County Down. Lanré Charles Olagoke. Founder, Art-Alive Arts Trust. For services to Charity and to Young People. David Edward Olney. Assistant Head Ukraine, Security Policy and Operations, Ministry of Defence. For services to Defence. Tori Pamela Anne Olphin. Chief Data Scientist and Head of Research, Thames Valley Police. For services to Technology in the Public Sector. Ehinor Otaigbe-Amedu. For services to Women in Greater Manchester. Lydia Jean Otter.
Sources: en.wikipedia.org
Susan Weintraub is an American scientist. She is a professor at the University of Texas Health Science Center at San Antonio (UTHSCSA). She received a BS in chemistry from the University of Pennsylvania in 1967, MS in chemistry from Trinity University in 1970 and a PhD in biochemistry from UTHSCSA in 1979. She was the president of the American Society for Mass Spectrometry for the period of 2012-2014. In 2017 she was named a Fellow of the American Association for the Advancement of Science (AAAS), and Fellow of the American Society for Mass Spectrometry in 2025. She is an associate editor of the Journal of Proteome Research. Her research focuses on biomedical mass spectrometry where she used mass spectrometry in the early 1970s for quantitative analysis of brain neurochemicals. She has been director of the mass spectrometry core resource at UTHSCSA since 1979.
. Moreover population dynamics like birth and death processes can be included. Such complex models enable a deeper understanding of infection dynamics and the introduction of different pharmaceutical and non-pharmaceutical interventions.
== Professional career == Esimone started his career as internee pharmacist and then became a laboratory instructor, all in the Department of Pharmaceutics, University of Nigeria Nsukka. He became a professor of biopharmaceutics and pharmaceutical microbiology at the age of 37 years and was the pioneer Dean, Faculty of Pharmaceutical Sciences, Agulu Campus of Nnamdi Azikiwe University Awka. He also served two terms of 2 years each as the Deputy Vice-Chancellor (Academics) of Nnamdi Azikiwe University, Awka. He is a researcher with well over 100 publications and in May 2019 was ranked 18th on the list of 28 Most Published Scholars in Nigeria. Prof. Esimone was also the Director of Confucius Institute of Nnamdi Azikiwe University, Awka. On the 14 of May 2019 he was elected the new Vice Chancellor of Nnamdi Azikiwe University, Awka. He is the State Campus Coordinator for Deeper Life Campus Fellowship, Anambra State and also a member, BOT (Board of Trustees) of Anchor University, Lagos.
== Applications == PEEK is used to fabricate items for demanding applications, including bearings, piston parts, pumps, high-performance liquid chromatography columns, compressor plate valves, and electrical cable insulation. Because of its low moisture uptake, it is one of the few plastics compatible with ultra-high vacuum applications, which makes it suitable for aerospace, automotive, and chemical industries. PEEK is used in medical implants, for example in creating a partial replacement skull in neurosurgical applications. PEEK is used in spinal fusion devices and reinforcing rods. It is radiolucent, but it is hydrophobic causing it to not fully fuse with bone. PEEK seals and manifolds are commonly used in fluid applications. PEEK also performs well in high temperature applications (up to 260 °C/500 °F). Because of this and its low thermal conductivity, it is also used in fused filament fabrication (FFF) printing to thermally separate the hot end from the cold end.
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.
Identity is confirmed by matching the retention time in reversed-phase chromatography against a reference standard and by measuring the molecular mass with mass spectrometry. Tandem mass spectrometry or amino acid analysis can verify the sequence of the seven residues. Because the peptide contains no aromatic amino acids, detection at 280 nm is not useful.