If you have been reading about RP-HPLC and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-12-04. Where a claim depends on a specific study, the study is described rather than over-claimed.
Early work on thymic extracts in the 1960s described a heat-stable acidic fraction containing many polypeptides. Separation of that mixture yielded individual components, and thymosin alpha-1 was named as one of them on the basis of assays for T-cell activity. The first preparations came from calf thymus, while subsequent research and clinical material has been chemically synthesized. Nomenclature in older papers is inconsistent, and the same peptide sometimes appears under different designations, which complicates literature searches.
Most published studies on thymosin alpha-1 report changes in immune measurements rather than clinical outcomes, and findings differ across designs and populations. Whether the peptide signals through one defined receptor or through several less specific interactions remains an open question. Its reported circulation half-life of a few hours complicates comparison of dosing schedules across trials. Mechanistic claims are frequently drawn from isolated cell cultures, and how far those results extend to whole organisms is unresolved.
Identity and purity are normally confirmed by reversed-phase high-performance liquid chromatography and mass spectrometry. The expected mass for the acetylated 28-residue peptide is close to 3108 daltons, and a mass shift indicates a modification or truncation. Peptide mapping after enzymatic digestion can resolve sequence-level questions. Counter-ion content, water content, and residual solvents are separate quality attributes that a certificate of analysis may or may not report. Aggregation is monitored by size-exclusion chromatography when relevant.
Thymosin alpha-1 is supplied as a lyophilized powder in most research settings. The solid dissolves readily in water and in common aqueous buffers, and it is typically reconstituted shortly before use. Solutions are clear and colourless at ordinary working concentrations. Because the peptide is hygroscopic, weighing and reconstitution are usually performed with minimal exposure to ambient air. Aliquots are prepared to avoid repeated freeze-thaw cycles, and working solutions are kept cold.
| Property | Value | Notes |
|---|---|---|
| Class | Synthetic peptide | 28 residues; not a small-molecule compound |
| Molecular mass | About 3,106 Da | Monoisotopic mass of the unmodified chain |
| N-terminal group | Acetylated serine | Present in both native and synthetic forms |
| Secondary structure | Disulfide-constrained loop | One bridge between two cysteine residues |
| Typical source | Solid-phase synthesis | Early isolates came from bovine thymus extracts |
== Notable people == Michael Dunn, Oscar- and Tony-nominated American actor, The Wild Wild West, Star Trek Warwick Davis, English actor and TV presenter, Willow, Return of the Jedi, Leprechaun film series. His two children also have SED. Lenny Rush, English actor, Am I Being Unreasonable? Natalia Grace, Ukrainian-born American with dwarfism, The Curious Case of Natalia Grace Alexander Katan, Dutch Jewish accountant, teacher, and translator who was murdered by the Nazis during the Holocaust, photos of him were notoriously on display in various museums.
Ibogaine biosynthesis begins with tryptophan undergoing enzymatic decarboxylation by tryptophan decarboxylase (TDC) to form tryptamine. Secologanin, an iridoid synthesized from isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), is reacted with tryptamine to make strictosidine. A glycosidic bond cleavage of strictosidine by strictosidine β-deglucosidase (SGD) produces a lactol. The lactol opens and produces an aldehyde, then condenses to form an iminium. Through isomerization and reduction by geissoschizine synthase 1 (GS1), 19E-geissoschizine is yielded. The indole is oxidized, and the molecule undergoes an intramolecular Mannich reaction and Grob fragmentation to form preakuammicine. Preakuammicine is highly unstable and therefore reduced to stemmadenine by oxidation-reduction reactions (REDOX 1 and REDOX 2). Stemmadine is acylated by stemmadine Ο-acetyltransferase (SAT) to yield stemmadine acetate. Through oxidation by precondylocarpine acetate synthase (PAS) and reduction by dihydroprecondylocarpine acetate synthase (DPAS), an enamine intermediate is formed. The intermediate undergoes fragmentation to produce an iminium that tautomerizes to yield dehydrosecodine. Coronaridine synthase (CorS) catalyzes the isomerization of dehydrosecodine, and an unusual cycloaddition is completed. DPAS and NADPH reduce the iminium to form (-)-coronaridine. There are two pathways (-)-coronaridine can take to become (-)-ibogaine.
Yeast extracts consist of the cell contents of yeast without the cell walls; they are used as food additives or flavorings, or as nutrients for bacterial culture media. They are often used to create savoury flavors and umami taste sensations and can be found in a large variety of packaged foods including frozen meals, crackers, snack foods, gravy, stock and more. They are rich in B vitamins (but not B12). Yeast extracts and fermented foods contain glutamic acid (free glutamates), an amino acid which adds an umami flavor. Glutamic acid is found in meat, cheese, fungi (mushrooms and yeast) and vegetables—such as broccoli and tomatoes. A number of other substances found in yeast extract provide aromas, some meat-like, when allowed to react under heat. The thermal process to make yeast extract of the autolysate type was invented in the 19th century by Justus von Liebig. Yeast cells are heated until they rupture, then the cells' own digestive enzymes combined with the intense heat help to break large proteins down into simpler compounds (amino acids and peptides), a process called autolysis. The insoluble cell walls are then separated by centrifuge, filtered, and usually spray-dried. This is the process used for spreads such as Vegemite and Marmite. Yeast extracts in liquid form can be dried to a light paste or a dry powder. This is not the same as nutritional yeast seasonings, which are made from lyophilized intact cells and consequently have a lighter flavor.
On 16 May 2023, three weeks after Tangaraju was put to death, 36-year-old Muhammad Faizal Mohd Shariff, a Singaporean who was found guilty in 2019 of trafficking 1.5 kg of marijuana was reported to have lost his final appeal to commute his sentence. A day after losing his appeal, Muhammad Faizal was hanged at dawn on 17 May 2023, with the authorities confirming his execution despite not naming Muhammad Faizal out of consideration for his family's need for privacy. Two executions of a 56-year-old man and 45-year-old woman (both convicted of drug offences) were scheduled to take place on 26 July and 28 July 2023 respectively; the female offender Saridewi Djamani was believed to be the first woman to be executed in 19 years, as the last known execution of a woman took place on 19 March 2004, when 37-year-old Yen May Woen was put to death for diamorphine trafficking. The 56-year-old male drug offender Mohd Aziz Hussain, as well as Saridewi, were both hanged as scheduled, becoming the third and fourth persons respectively to be executed in Singapore in the year of 2023. On 3 August 2023, Singapore carried out the hanging of Mohamed Shalleh Abdul Latiff, a 39-year-old Singaporean and former delivery driver found guilty of trafficking 54.04g of diamorphine in 2016. In total, five executions, all once again for drug trafficking, took place in the year 2023. When 35-year-old Ahmed Salim was hanged on 28 February 2024 for murdering his former fiancée, he was the first criminal hanged in Singapore in that year.
==== Indications ==== Platelet transfusion is most frequently used to correct unusually low platelet counts, either to prevent spontaneous bleeding (typically at counts below 10 billion/L) or in anticipation of medical procedures that necessarily involve some bleeding. For example, in patients undergoing surgery, a level below 50 billion/L is associated with abnormal surgical bleeding, and regional anaesthetic procedures such as epidurals are avoided for levels below 80 billion/L. Platelets may also be transfused when the platelet count is normal but the platelets are dysfunctional, such as when an individual is taking aspirin or clopidogrel. Finally, platelets may be transfused as part of a massive transfusion protocol, in which the three major blood components (red blood cells, plasma, and platelets) are transfused to address severe hemorrhage. Platelet transfusion is contraindicated in thrombotic thrombocytopenic purpura (TTP), as it fuels the coagulopathy. Platelet transfusion is generally ineffective, and thus contraindicated, for prophylaxis in immune thrombocytopenia (ITP), because the transfused platelets are immediately cleared; however, it is indicated to treat bleeding.
Sources: en.wikipedia.org
== References == "Trichopsis vittata". Integrated Taxonomic Information System. Retrieved 11 March 2006. Froese, Rainer; Pauly, Daniel (eds.). "Trichopsis vittata". FishBase. February 2014 version. Ladich, F., W. Brtittenger, and H. Kratochvil (1992). Significance Of Agonistic Vocalization In The Croaking Gourami. Shafland, P. L. (1996). "Exotic Fishes of Florida-1994". Reviews in Fisheries Science 4(2). Sterba, G. (1983). The Aquarium Fish Encyclopedia. The MIT Press.
A number of Neanderthal fossils had been discovered before their antiquity was fully understood. The first Neanderthal remains—Engis 2 (a skull)—were discovered in 1829 by Dutch/Belgian prehistorian Philippe-Charles Schmerling in the Grottes d'Engis, Belgium. He concluded that these "poorly developed" human remains must have been buried at the same time and by the same causes as the co-existing remains of extinct animal species. In 1848, Gibraltar 1 from Forbes' Quarry was presented to the Gibraltar Scientific Society by their Secretary Lieutenant Edmund Henry Réné Flint, but was thought to be a modern human skull. In 1856, local schoolteacher Johann Carl Fuhlrott recognised bones from Kleine Feldhofer Grotte in Neander Valley—Neanderthal 1—as distinct from modern humans, and gave them to German anthropologist Hermann Schaaffhausen to study in 1857. It comprised the cranium, thigh bones, right arm, left humerus and ulna, left ilium (hip bone), part of the right shoulder blade, and pieces of the ribs.
Since 1947, the Doomsday Clock of the Bulletin of the Atomic Scientists has visualized how close the world is to a nuclear war. The Doomsday Clock reached a high point in 1953, when the Clock was set to two minutes until midnight after the U.S. and the Soviet Union began testing hydrogen bombs, and in 2018, following the failure of world leaders to address tensions relating to nuclear weapons and climate change issues. Since 2026, the Clock has been set at 85 seconds to midnight, the closest it has ever been.
== External links == CRBN protein, human at the U.S. National Library of Medicine Medical Subject Headings (MeSH) Overview of all the structural information available in the PDB for UniProt: Q96SW2 (Protein cereblon) at the PDBe-KB.
Sources: en.wikipedia.org
Its sequence corresponds to the amino-terminal portion of prothymosin alpha, a larger protein present in many cell types. The isolated 28-residue peptide is a fragment of that protein rather than a separately encoded molecule, and laboratory material is produced by synthesis.
The single bridge between two cysteine residues holds the chain in a folded loop that influences its shape and its behavior in solution. Loss of the bridge through reduction or oxidation shifts chromatographic retention and is tracked during stability work.
It is a defined 28-residue sequence derived from a larger precursor, whereas many other thymic preparations are mixtures of several polypeptides. Its acetylated amino terminus and single disulfide bridge distinguish it chemically from unrelated thymic extracts.
Lyophilized powder is normally kept at minus twenty degrees Celsius or below, in a sealed container, desiccated and away from light. Reconstituted solutions are less stable and are usually refrigerated and used quickly. Repeated temperature cycling should be avoided.