If you have been reading about prothymosin alpha 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 2026-03-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Quantifying thymosin alpha-1 in a sample usually relies on reverse-phase high-performance liquid chromatography. The peptide lacks strong chromophores, so detection often occurs at 214 nm, where the peptide backbone absorbs. Mass spectrometry provides confirmatory identification and can detect sequence variants or truncations. Immunoassays have been used in biological matrices, but they may cross-react with related fragments. For purity assessment, chromatographic peak area gives the main component percentage, while mass accuracy verifies molecular identity.
The lyophilized peptide is generally stable for extended periods when kept cold and dry. Once dissolved, aqueous solutions are less stable; hydrolysis, oxidation, and aggregation can degrade the material. Storage at -20 °C or lower slows these processes. Repeated freeze-thaw cycles are best avoided because they can promote aggregation. The exact shelf life depends on formulation, pH, and concentration, so stability studies are typically performed for each specific product.
Quality control for thymosin alpha-1 focuses on identity, purity, and potency. Identity is confirmed by mass spectrometry and amino acid analysis, while purity is assessed by chromatography with limits on related substances and residual solvents. Potency assays may use cell-based immune readouts, but these are not standardized across laboratories. Regulatory status differs by jurisdiction; no product is approved in the United States for clinical use, whereas some other countries register injectable forms for specific indications.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids, corresponding to the N-terminal fragment of prothymosin alpha. Its sequence begins with acetylation at the N-terminus, a modification that affects stability and receptor interaction. The peptide is acidic, with a calculated isoelectric point near 4.2, and carries no disulfide bonds, so its secondary structure is largely flexible in solution. Molecular mass is approximately 3108 daltons. The native form was first isolated from bovine thymus tissue, while pharmaceutical material is produced by solid-phase peptide synthesis.
Within the immune system, the peptide acts on several cell types rather than a single target. Reported activities include promotion of T-cell maturation, enhancement of natural killer cell activity, and modulation of cytokine production by dendritic cells and macrophages. Some of these effects appear to operate through toll-like receptor signaling, though the precise receptor-level mechanism remains debated. Whether the observed immune changes translate into clinical benefit is a separate question and depends on the indication studied.
The peptide was described in the 1970s as a component of thymic extracts, and early research focused on restoring immune function in immunodeficiency states. A synthetic version entered clinical development in the 1980s and is approved as a drug in several countries for conditions such as chronic hepatitis B and certain immunodeficiencies. Approval status varies widely by jurisdiction, and in the United States it is not an approved therapeutic. Regulatory and clinical positions differ, so statements about efficacy should be tied to specific indications and studies.
| Property | Value | Notes |
|---|---|---|
| Detection wavelength | 214 nm | Peptide bond absorption; 280 nm is not useful. |
| Confirmatory method | Electrospray mass spectrometry | Verifies mass near 3108 Da. |
| Solution stability | Limited at room temperature | Aqueous solutions degrade faster than powder. |
| Recommended storage | -20 °C | For lyophilized powder; protect from moisture. |
| Purity criterion | ≥95% by RP-HPLC | Typical research-grade specification. |
Commission E1: Air Conditioning "Commission E1: Air Conditioning" often collaborates with "Commission E2: Heat Pumps and Energy Recovery" as they have at least one common aspect, the compressor. Both Commissions frequently work with the same equipment, which is adapted according to the seasons, alternating between air conditioners and heat pumps. The commission is involved in various aspects of air conditioning, from equipment to systems. In recent years, it has developed a particular focus on energy saving and sustainability, whilst maintaining good conditions of thermal comfort, ranging from topics such as free cooling, solar cooling or long-term energy storage. The general importance of the themes addressed by the Commission results in relevant International Conferences. Commission members work on new refrigerants in air conditioning systems, annual comparative studies of renewable energy systems, part-load operation of air conditioning systems, and related research fields.
=== Gold plating === For space missions, gold is used because it is useful at reflecting light, which helps to detect celestial objects from far away and gold does not oxidize so it will not tarnish, unlike most other metals. Due to both benefits, the James Webb Space Telescope uses gold on its mirrors. NASA partnered with Epner Technology, a Brooklyn-based business that has been gold-plating for generations to develop the technology to gold plate the telescope's parts. This NASA technology transfer to Epner gave the company a reputation for durable gold coatings. Academy of Motion Picture Arts and Sciences occasionally needs to replate Oscar statues that have faded over time. Epner has contracted with the academy to gold plate all future Oscars while offering a lifetime guarantee to replate, for free, any faded Oscar; its gold plating has lasted for decades in space without fading.
In 1515, the scholar Qasim from Herat in contrast had identified both wild and garden tulips (lale) as anemones (shaqayq al-nu'man) but described the crown imperial as laleh kakli. In a Turkic text written before 1495, the Chagatay Husayn Bayqarah mentions tulips (lale). Babur, the founder of the Mughal Empire, also names tulips in the Baburnama. He may actually have introduced them from Afghanistan to the plains of India, as he did with other plants like melons and grapes. The tulip represents the official symbol of Turkey. In Moorish Andalus, a "Makedonian bulb" (basal al-maqdunis) or "bucket-Narcissus" (naryis qadusi) was cultivated as an ornamental plant in gardens. It was supposed to have come from Alexandria and may have been Tulipa sylvestris, but the identification is not wholly secure.
Sources: en.wikipedia.org
S-adenosyl-L-homocysteine + [myelin basic protein]-Nomega-methyl-arginine Thus, the two substrates of this enzyme are S-adenosyl methionine and myelin basic protein-arginine, whereas its two products are S-adenosylhomocysteine and myelin basic protein-Nomega-methyl-arginine. This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:[myelin-basic-protein]-arginine Nomega-methyltransferase. Other names in common use include myelin basic protein methylase I, protein methylase I, S-adenosyl-L-methionine:[myelin-basic-protein]-arginine, and omega-N-methyltransferase.
electron capture A type of nuclear transformation by which the proton-rich nucleus of an electrically neutral atom absorbs or 'captures' an electron from one of its own inner shells, often those closest to the nucleus, which provokes a reaction that results in a nuclear proton changing into a neutron accompanied by the simultaneous emission of an electron neutrino.
9 June – A study in the Journal of Peace Research, using data from the Uppsala Conflict Data Program, reports a record 65 state-based armed conflicts in 2025, including eight interstate conflicts, the highest number since data collection began in 1946. It estimates that 244,600 people were killed in organised violence during the year, driven partly by a sharp rise in one-sided violence against civilians in Sudan. 11 June – The National Oceanic and Atmospheric Administration declares the onset of an El Niño event in the tropical Pacific, and forecasts a 63% chance that it will rank among the largest since records began in 1950. 18 June – A study published in The Lancet, led by Queen Mary University of London and funded by Cancer Research UK, estimates that the HPV vaccine has prevented around 200 deaths from cervical cancer in England, and finds that no women aged 20–24 died from the disease between 2020 and 2024, the first such period on record. 19 June – A study published in Science Advances finds that high-end but physically plausible meltwater from the Greenland ice sheet could significantly worsen the long-term weakening of the Atlantic meridional overturning circulation (AMOC), especially after 2100, but does not make projected AMOC changes abrupt or irreversible on centennial timescales in the model used. In a carbon dioxide reversal experiment beginning in 2250, AMOC strength recovers after carbon dioxide concentrations return to 2015 levels by around the year 2420.
A Novichok agent was used in 1995 to poison Russian banker Ivan Kivelidi, who died three days later in a hospital at the age of 46. The poison was believed to have been applied to Kivelidi's office phone in Moscow. His secretary Zara Ismailova also developed symptoms one month later and then died a day later in a hospital at the age of 35. Kivelidi was the head of the Russian Business Round Table, and had close ties to Viktor Chernomyrdin, who was at that time Prime Minister of Russia. Russian opposition–linked historians Yuri Felshtinsky and Vladimir Pribylovsky speculated that the murder became "one of the first in the series of poisonings organised by Russia's security services". The Russian Ministry of Internal Affairs analysed the substance and announced that it was "a phosphorus-based military-grade nerve agent" "whose formula was strictly classified". According to Nesterov, the administrative head of Shikhany, he did not know of "a single case of such poison being sold illegally" and noted that the poison "is used by professional spies". Vladimir Khutsishvili, a former business partner of Kivelidi's, was subsequently convicted of the killings. According to The Independent, "A closed trial found that his business partner had obtained the substance via intermediaries from an employee of the State Research Institute of Organic Chemistry and Technology (ГосНИИОХТ / GosNIIOKhT), which was involved in the development of Novichok agents. However, Khutsishvili, who claimed that he was innocent, had not been detained at the time of the trial and freely left the country.
Sources: en.wikipedia.org
=== 2010–2013: Films with high-profile directors === DiCaprio continued to collaborate with Scorsese in the 2010 psychological thriller film Shutter Island, based on the 2003 novel of the same name by Dennis Lehane. He played Edward "Teddy" Daniels, a U.S. Marshal investigating a psychiatric facility located on an island, who comes to question his own sanity. DiCaprio and Scorsese became interested in the project in 2007, and the former co-produced the film under Appian Way with Phoenix Pictures. Because of the film's disturbing scenes, DiCaprio had nightmares of mass murder during production and considered relaxing with his friends a form of therapy. The film was released to mixed reviews; Peter Bradshaw of The Guardian praised Scorsese's direction and the acting but criticized its twist ending. Peter Travers called it DiCaprio's "most haunting and emotionally complex performance yet", and particularly liked his cave scene with co-star Patricia Clarkson. The film was a commercial success, grossing $294 million worldwide against a budget of $80 million.
The carpal tunnel is an anatomical compartment located at the base of the palm. Nine flexor tendons and the median nerve pass through the carpal tunnel, which is surrounded on three sides by the carpal bones that form an arch. The median nerve provides feeling or sensation to the thumb, index finger, long finger, and half of the ring finger. At the level of the wrist, the median nerve supplies the muscles at the base of the thumb that allow it to abduct, move away from the other four fingers, as well as move out of the plane of the palm. The carpal tunnel is located at the middle third of the base of the palm, bounded by the bony prominence of the scaphoid tubercle and trapezium at the base of the thumb, and the hamate hook that can be palpated along the axis of the ring finger. From the anatomical position, the carpal tunnel is bordered on the anterior surface by the transverse carpal ligament, also known as the flexor retinaculum. The flexor retinaculum is a strong, fibrous band that attaches to the pisiform and the hamulus of the hamate. The proximal boundary is the distal wrist skin crease, and the distal boundary is approximated by a line known as Kaplan's cardinal line. This line uses surface landmarks, and is drawn between the apex of the skin fold between the thumb and index finger to the palpated hamate hook.
== Isotope ratio measurement == The relative abundances of different isotopes are then used to describe the chemical fractionation of different isotopes, travel in different reservoirs of non-radiogenic isotopes, and age or origins of solar system objects by the presence of radiogenic daughter isotopes. Elemental analysis is a predominant application of TIMS as it gives reliable isotopic ratios. Following the trend of decreasing ionization energy, elements located towards the bottom left of the periodic table are viable for TIMS. In addition, the high electron affinity seen towards the upper right of the periodic table makes these nonmetals excellent candidates. The technique is used extensively in isotope geochemistry, geochronology, and in cosmochemistry. Quantitative isotope ratio techniques include isotope dilution thermal ionization mass spectrometry (ID-TIMS) and chemical abrasion thermal ionization mass spectrometry (CA-TIMS). Isotope dilution method is used because the signal intensity in TIMS isn't proportional to the amount that is placed into TIMS. For age dating, mass spectrometers with magnetic sectors have better precision than a quadrupole mass spectrometer or quadrupole mass analyzer. Inductively coupled plasma-quadrupole mass spectrometers allows for an even higher precision of detecting the change of isotopic ratios by radioactive decay. The more precision means the higher resolution in age dating.
Sources: en.wikipedia.org
Reverse-phase HPLC with ultraviolet detection at 214 nm is common. Mass spectrometry is used to confirm molecular identity and detect modifications. Immunoassays exist but may not distinguish the intact peptide from fragments.
The lyophilized powder is usually stored at -20 °C or below. Dissolved solutions are less stable and should be prepared fresh when possible. Freeze-thaw cycling can reduce integrity.
It lacks aromatic residues, so it does not absorb strongly at 280 nm. Its negative charge and hydrophilic nature can affect chromatographic retention. These properties require method development for reliable separation.
It corresponds to a fragment of the larger protein prothymosin alpha, which is present in many tissues. The isolated 28-amino-acid peptide was originally obtained from thymus preparations, and the pharmaceutical product is synthesized rather than extracted. The term therefore describes both a natural fragment and a manufactured drug substance.