The short version of prothymosin alpha fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-12-22 and is reviewed periodically as new material appears.
Stability depends on temperature, pH, and the number of freeze-thaw events the sample has experienced. Freeze-dried material is commonly held at -20 °C or colder, while reconstituted liquid is kept cold and used within a short window. Extreme pH and prolonged light exposure can promote deamidation, oxidation, or aggregation, particularly at asparagine and methionine positions. Adsorption to container walls can lower the measured concentration of a dilute solution even when the peptide molecules themselves remain intact.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or chemically modified byproducts. Mass spectrometry confirms the expected molecular mass and can indicate acetylation state or sequence errors. Amino acid analysis and peptide mapping supply complementary sequence-level information, while endotoxin testing is relevant for preparations intended for cell or animal work. Purity figures reported by suppliers refer to the method used and are not directly comparable across laboratories unless conditions are stated.
The peptide occurs naturally in thymic tissue and has been detected in serum and other biological fluids. Reported concentrations are low, and reliable measurement generally requires immunoassay or mass spectrometry with an enrichment step. It is released from a larger precursor, prothymosin alpha, by proteolytic cleavage, although the enzymes involved are not fully characterized. Whether circulating levels reflect thymic output specifically remains an open question.
Thymosin alpha 1 is a 28-amino-acid peptide first isolated from thymosin fraction 5, a bovine thymic extract. Its sequence begins with an acetylated serine residue and carries a high proportion of acidic residues, so the molecule has a net negative charge near neutral pH. Despite the shared name, it is unrelated in sequence to the thymosin beta family. Synthetic material prepared by solid-phase peptide synthesis is identical in sequence to the natural peptide.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white lyophilized powder | Visual description varies by batch |
| Solubility | Freely soluble in water | Aqueous buffers are commonly used |
| Typical storage temperature | -20 °C or below for powder | Reconstituted liquid kept at 2-8 °C short term |
| Purity method | Reversed-phase HPLC | Value derived from peak area integration |
| Identity method | Mass spectrometry | Confirms mass and sequence integrity |
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Findings across trials are mixed; some report changes in selected immune markers, while others find no clear clinical benefit. Many studies are small and define outcomes differently, which limits comparison. Regulatory approval is confined to a few countries, and the compound is not an approved drug in the United States or most of Europe.
Overall evidence quality varies considerably. A large share of published reports come from single centers, rely on surrogate immunological markers, or lack adequate control groups. Systematic reviews have highlighted this heterogeneity as a barrier to pooling results. Open questions include which patients, if any, might benefit, what treatment duration is appropriate, and whether any effect is independent of standard care. The peptide is often described as an immune modulator rather than a therapy for one disease, which complicates confirmatory trial design.
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.
Laboratory work indicates that the peptide acts on cells of both the innate and adaptive immune systems. Reported effects include signalling through Toll-like receptors on dendritic cells, enhanced T-cell maturation, and increased natural killer cell activity. These actions are described largely from cell-culture and animal experiments, and the precise receptor-level events remain incompletely defined. Studies in humans have generally measured immune markers rather than a single defined molecular target. The resulting picture remains partly descriptive.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Results across trials have been mixed, and several studies were small or conducted under differing protocols. Regulatory status varies by country, and the compound is not approved in every jurisdiction where it is studied. Evidence for any single indication should be read with attention to sample size and endpoint choice.
Thymosin alpha-1 is a 28-residue peptide first isolated from thymus tissue in the 1970s. It corresponds to the N-terminal portion of thymosin beta-4, from which it is cleaved in vivo. The peptide carries an acetyl group at its N-terminus, a modification that affects its charge and stability. Synthetic material produced by solid-phase peptide synthesis is chemically identical to the natural fragment and is the form used in research and clinical studies.
Due to their similar atomic radii, rubidium and caesium in the body mimic potassium and are taken up similarly. Rubidium has no known biological role, but may help stimulate metabolism, and, similarly to caesium, replace potassium in the body causing potassium deficiency. Partial substitution is quite possible and rather non-toxic: a 70 kg person contains on average 0.36 g of rubidium, and an increase in this value by 50 to 100 times did not show negative effects in test persons. Rats can survive up to 50% substitution of potassium by rubidium. Rubidium (and to a much lesser extent caesium) can function as temporary cures for hypokalemia; while rubidium can adequately physiologically substitute potassium in some systems, caesium is never able to do so. There is only very limited evidence in the form of deficiency symptoms for rubidium being possibly essential in goats; even if this is true, the trace amounts usually present in food are more than enough. Caesium compounds are rarely encountered by most people, but most caesium compounds are mildly toxic. Like rubidium, caesium tends to substitute potassium in the body, but is significantly larger and is therefore a poorer substitute. Excess caesium can lead to hypokalemia, arrhythmia, and acute cardiac arrest, but such amounts would not ordinarily be encountered in natural sources. As such, caesium is not a major chemical environmental pollutant. The median lethal dose (LD50) value for caesium chloride in mice is 2.3 g per kilogram, which is comparable to the LD50 values of potassium chloride and sodium chloride.
The high percentage of alcohol in absinthe would result in mortality long before thujone could become a factor. In documented cases of acute thujone poisoning as a result of oral ingestion, the source of thujone was not commercial absinthe, but rather non-absinthe-related sources, such as common essential oils (which may contain as much as 50% thujone). One study published in the Journal of Studies on Alcohol concluded that high doses (0.28 mg/kg) of thujone in alcohol had negative effects on attention performance in a clinical setting. It delayed reaction time, and caused subjects to concentrate their attention on the central field of vision. Low doses (0.028 mg/kg) did not produce an effect noticeably different from the plain alcohol control. While the effects of the high dose samples were statistically significant in a double blind test, the test subjects themselves were unable to reliably identify which samples contained thujone. For the average 65 kg (143 lb) man, the high dose samples in the study would equate to 18.2 mg of thujone. The EU limit of 35 mg/L of thujone in absinthe means that given the highest permitted thujone content, that individual would need to consume approximately 0.5 litres of high-proof (e.g. 50%+ ABV) spirit before the thujone could be metabolized to display effects detectable in a clinical setting, which would result in a potentially lethal BAC of >0.4%.
Progestogens, including both progesterone and progestins, are used medically in hormonal birth control, hormone therapy, to treat gynecological disorders, to suppress sex hormone levels for various purposes, and for other indications.
=== Doping in sport === There was a case in the World Anti-Doping Agency practice in 2007, when an athlete, who reportedly consumed Yohimbine prior to a given athletic event, was later tested positive for 19-norandrosterone, which is a prohibited substance. However, WADA did not yet list Yohimbine (which can come into a body via an energy drink, also in a form of pre-workout supplement or fat burner) as a prohibited substance, nor did it confirm that its use can increase the endogenous level of anabolic steroids, in particular of 19-norandrostenedione and testosterone.
=== Dosimetry === The radiation absorbed dose is the amount energy absorbed per unit weight of the target material. Dose is used because, when the same substance is given the same dose, similar changes are observed in the target material(Gy or J/kg). Dosimeters are used to measure dose, and are small components that, when exposed to ionizing radiation, change measurable physical attributes to a degree that can be correlated to the dose received. Measuring dose (dosimetry) involves exposing one or more dosimeters along with the target material. For purposes of legislation doses are divided into low (up to 1 kGy), medium (1 kGy to 10 kGy), and high-dose applications (above 10 kGy). High-dose applications are above those currently permitted in the US for commercial food items by the FDA and other regulators around the world, though these doses are approved for non commercial applications, such as sterilizing frozen meat for NASA astronauts (doses of 44 kGy) and food for hospital patients. The ratio of the maximum dose permitted at the outer edge (Dmax) to the minimum limit to achieve processing conditions (Dmin) determines the uniformity of dose distribution. This ratio determines how uniform the irradiation process is.
Sources: en.wikipedia.org
=== Mutations === Heterozygous loss-of-function mutations in the YAP1 gene have been identified in two families with major eye malformations with or without extra-ocular features such as hearing loss, cleft lip, intellectual disability and renal disease.
==== Fistula formation and gallstone ileus ==== The inflammation of cholecystitis can lead to adhesions between the gallbladder and other parts of the gastrointestinal tract, most commonly the duodenum. These adhesions can lead to the formation of direct connections between the gallbladder and gastrointestinal tract, called fistulas. With these direct connections, gallstones can pass from the gallbladder to the intestines. Gallstones can get trapped in the gastrointestinal tract, most commonly at the connection between the small and large intestines (ileocecal valve). When a gallstone gets trapped, it can lead to an intestinal obstruction, called gallstone ileus, leading to abdominal pain, vomiting, constipation, and abdominal distension.
As mentioned above, the naturally occurring nucleotides (nucleoside-3'- or 5'-phosphates) and their phosphodiester analogs are insufficiently reactive to afford an expeditious synthetic preparation of oligonucleotides in high yields. The selectivity and the rate of the formation of internucleosidic linkages is dramatically improved by using 3'-O-(N,N-diisopropyl phosphoramidite) derivatives of nucleosides (nucleoside phosphoramidites) that serve as building blocks in phosphite triester methodology. To prevent undesired side reactions, all other functional groups present in nucleosides have to be rendered unreactive (protected) by attaching protecting groups. Upon the completion of the oligonucleotide chain assembly, all the protecting groups are removed to yield the desired oligonucleotides. Below, the protecting groups currently used in commercially available and most common nucleoside phosphoramidite building blocks are briefly reviewed:
Gelatine art desserts, also known as 3D gelatine desserts, are made by injecting colourful shapes into a flavoured gelatine base. Creations by Lourdes Reyes Rosas of Mexico City kicked off the growth in popularity of this 3D gelation art technique in the early 1990s, which spread to Western and Pacific countries. These desserts are made using high-quality gelatine that has a high bloom value and low odour and taste. The clear gelatine base is prepared using gelatine, water, sugar, citric acid and food flavouring. When the clear gelatine base sets, colourful shapes are injected using a syringe. The injected material usually consists of a sweetener (most commonly sugar), some type of edible liquid (milk, cream, water, etc.), food colouring and a thickening agent such as starch or additional gelatine. The shapes are drawn by making incisions in the clear gelatine base using sharp objects. Coloured liquid is then allowed to fill the crevice and make the cut shape visible. Most commonly, the shapes are drawn using sterile medical needles or specialised pre-cut gelatine art tools that allow the shape to be cut and filled with colour at the same time. Gelatine art tools are attached to a syringe and used to inject a predetermined shape into gelatine. When combined with other ingredients, such as whipping cream or mousse, gelatine art desserts can be assembled into formations resembling a cake.
Sources: en.wikipedia.org
Succimer is indicated for the treatment of lead poisoning in children with blood level measured above 45 μg/dL. The use of dimercaptosuccinic acid is not approved for prevention of lead poisoning in anticipation of exposure in known lead-contaminated environments. Dimercaptosuccinic acid can cross the blood–brain barrier of mice, but it is not known if this is also the case in humans. Even if dimercaptosuccinic acid cannot reverse the damages done to the central nervous system, it might prevent further deterioration. Succimer facilitates urinary excretion of lead, and with sufficiently aggressive treatment, can reduce lead content in the brain. It also increases urinary excretion of copper and zinc. Dimercaptosuccinic acid improved cognitive function in rats that had been exposed to lead, but reduced cognitive function in rats that had not been exposed to lead.
The acetolactate synthase (ALS) enzyme (also known as acetohydroxy acid or acetohydroxyacid synthase, abbr. AHAS) is a protein found in plants and micro-organisms. ALS catalyzes the first step in the synthesis of the branched-chain amino acids (valine, leucine, and isoleucine).
Bernoulli's principle can be used to calculate the lift force on an airfoil, if the behaviour of the fluid flow in the vicinity of the foil is known. For example, if the air flowing past the top surface of an aircraft wing is moving faster than the air flowing past the bottom surface, then Bernoulli's principle implies that the pressure on the surfaces of the wing will be lower above than below. This pressure difference results in an upwards lifting force. Whenever the distribution of speed past the top and bottom surfaces of a wing is known, the lift forces can be calculated (to a good approximation) using Bernoulli's equations, which were established by Bernoulli over a century before the first man-made wings were used for the purpose of flight. The basis of a carburetor used in many reciprocating engines is a throat in the air flow to create a region of low pressure to draw fuel into the carburetor and mix it thoroughly with the incoming air. The low pressure in the throat can be explained by Bernoulli's principle, where air in the throat is moving at its fastest speed and therefore it is at its lowest pressure. The carburetor may or may not use the difference between the two static pressures which result from the Venturi effect on the air flow in order to force the fuel to flow, and as a basis a carburetor may use the difference in pressure between the throat and local air pressure in the float bowl, or between the throat and a Pitot tube at the air entry. An injector on a steam locomotive or a static boiler.
Sources: en.wikipedia.org
Cold storage slows the chemical degradation reactions that occur in solution. Lyophilized powder is more stable than reconstituted liquid and tolerates longer storage periods. Repeated temperature cycling should still be avoided because it can drive aggregation and loss of material.
Mass spectrometry is the standard confirmation of molecular mass and acetylation state. Chromatography establishes purity but does not identify the molecule on its own. The two techniques are normally applied together during verification.
No, because the reported value reflects the detection method and wavelength used, which vary between laboratories. A number stated without method details cannot be compared directly with another supplier's figure. Requesting the chromatogram and the method conditions is a common way to interpret it.
It is a 28-amino-acid peptide originally purified from a bovine thymic extract and later produced synthetically. It is studied mainly for its effects on immune cell function.