The short version of thymosin alpha-1 fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-03-02 and is reviewed periodically as new material appears.
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.
Long-term storage is generally at minus twenty degrees Celsius or colder, preferably desiccated and protected from light. Lyophilized material is more stable than reconstituted solution, which degrades faster at room temperature. Stability depends on pH, ionic strength, and the presence of oxidising agents. Published stability data for the peptide are limited, so storage claims in catalogues should be treated as general guidance rather than measured guarantees. Freeze-thaw cycles are kept to a minimum.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Soluble in water | Also soluble in aqueous buffers |
| Storage temperature | -20 °C or below | Desiccated, protected from light |
| Typical analytical method | RP-HPLC with mass spectrometry | Purity and identity |
| Common synonyms | Thymalfasin, T alpha 1 | Sequence identical to natural fragment |
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.
Several names appear in the literature for this peptide, including thymalfasin and the abbreviation T-alpha-1. Naming conventions differ among research articles, regulatory documents, and supplier catalogs, which complicates literature searches. Both synthetic and recombinant production routes yield a peptide with the same 28-residue sequence as the thymic isolate. Because the thymosin label also covers unrelated peptides, sources should be compared by sequence rather than by name alone.
Immunological studies connect the peptide to multiple parts of the immune response. It has been reported to engage Toll-like receptor signaling, to promote dendritic cell maturation, and to influence the balance of T helper cell subsets. Changes in natural killer cell activity and in cytokine release appear in cell culture and animal models. These observations describe broad immunomodulatory behavior rather than a single defined receptor target, and the primary molecular interaction has not been settled.
Thymosin alpha-1 is a synthetic 28-amino-acid peptide whose sequence was first identified in extracts of bovine thymus tissue during the 1970s. The chain carries an acetyl group on its N-terminal serine. Its acidic residue content is high, which produces strong water solubility and an isoelectric point well below neutrality. Material supplied for laboratory and clinical use is manufactured by solid-phase peptide synthesis rather than purified from animal tissue. Different salt forms, such as the acetate, alter the counter-ion content without changing the peptide backbone.
Whether the free 28-residue peptide circulates in human tissue remains debated. The best-documented human source is prothymosin alpha, a larger acidic protein that carries the sequence at its N-terminus. Reports of measurable peptide levels in serum and lymphoid tissue exist, yet some of that signal may come from cross-reacting fragments or from the parent protein. Most reviews therefore treat prothymosin alpha as the established human molecule and describe independent circulation of the small peptide as an unresolved question.
Botox is usually injected in the three lip elevator muscles that converge on the lateral side of the ala of the nose; the levator labii superioris (LLS), the levator labii superioris alaeque nasi muscle (LLSAN), and the zygomaticus minor (ZMi). In 2025 there were 19,701 professionals administering botox in the United Kingdom, an increase of 437% since 2023. There was a similar increase in the USA.
== Structure == OTC is a trimeric protein. There are three active sites of the protein which are located at the cleft between the monomers. The carbamoyl phosphate binding domain resides on the N-terminal end of each monomer, while the C-terminal end contains the binding domain for ornithine. Both binding domains have a similar structural pattern with a central parallel β-pleated sheet bordered by α-helices and loops. In addition to the binding domains, OTCs have SMG loops. These swing to close the binding site once both substrates have bound. SMG stands for the conserved amino acid motif of Ser-Met-Gly. Upon closure, these residues interact with L-ornithine. The binding of CP induces a global conformational change, while the binding of L-ornithine only induces movement of the SMG loop to close and isolate the activation site.
When SWAPO's executive committee proved unable to suppress the PLAN revolt, the Zambian National Defence Force (ZNDF) mobilised several army battalions and attacked the camps held by the mutineers, rounding up an estimated 1,800 PLAN dissidents. SWAPO's Secretary for Information, Andreas Shipanga, was found responsible by the Zambian government for inciting the revolt. Zambian president Kenneth Kaunda deported Shipanga and several other high-ranking dissidents to Tanzania, while incarcerating the others at remote army facilities. Sam Nujoma accused them of being South African agents and carried out a purge of the surviving political leadership and PLAN ranks. Forty mutineers were formally sentenced to death by a PLAN tribunal in Lusaka, and hundreds of others were subject to enforced disappearances. Additionally, the heightened tension between Kaunda's government and PLAN resulted in the ZNDF confiscating PLAN arms caches. The fallout from the Shipanga Affair prompted PLAN to relocate its headquarters from Lusaka to Lubango, Angola, at the invitation of the MPLA. It was joined shortly afterwards by SWAPO's political wing, which relocated to Luanda. SWAPO's closer affiliation and proximity to the MPLA may have influenced its concurrent slide to the left; the party adopted a more overtly Marxist discourse, such as a commitment to a classless society based on the ideals and principles of scientific socialism. From 1976 onward, SWAPO considered itself the ideological as well as the military ally of the MPLA.
=== Limitations === The UK Government's Department of Health compiled a factsheet in 2014, in which it is stated that the key limitations to well-being, quality of life and life satisfaction research are that:
In 2018, El Salvador cut diplomatic ties with Taiwan and recognized the People's Republic of China as China's legitimate government. This led to Bukele and the United States accusing China of interfering in Salvadoran and Latin American politics. Despite Bukele's criticism of China before becoming president, Vice President Félix Ulloa stated in May 2019 that Bukele's government would not restore diplomatic relations with Taiwan. In December 2019, Bukele met Chinese leader Xi Jinping in Beijing and signed a "gigantic" infrastructure agreement with China for an unknown amount of money. El Salvador and China have cooperated on infrastructure projects in El Salvador such as the National Library of El Salvador (completed in November 2023) and the National Stadium of El Salvador (construction began in November 2023). In November 2022, Bukele announced that El Salvador and China had begun negotiations for a free trade agreement between the countries. China donated fertilizer and wheat flour to El Salvador and, according to a Salvadoran government official, offered to buy El Salvador's external bond debt. Bukele stated that a free trade agreement with China was "very important" because El Salvador had been "isolated from [the] potential" of China's economic strength.
Sources: en.wikipedia.org
He mostly appears during radio transmissions while guiding Alyx and Gordon to White Forest, and argues bitterly with Magnusson, whom Vance states was Kleiner's rival for grant money at Black Mesa. Upon the discovery of the Borealis in Judith Mossman's decoded message, Kleiner expresses a wish to use the technology residing in the ship against the Combine, opposing Eli's vehement desire to destroy it in order to prevent "another Black Mesa".
Plants grown under UVB light are more resistant to insect herbivory compared with plants grown under filters that exclude the radiation. When tomato plants are exposed to a pulse of UVB radiation and then weakly wounded, PIs accumulate throughout the plant. By themselves, neither the radiation nor weak wounding is sufficient to induce systemic PI accumulation. Tomato cell cultures respond similarly, with systemin and UVB acting together to activate MAPKs. Short pulses of UVB also cause alkalisation of the culturing medium.
== Further reading == Bryan, J. III; Reed, Philip G. (1945). Mission Beyond Darkness: The story of USS Lexington's Air Group 16 June 20, 1944 attack on the Japanese carrier fleet as told by the men who flew that day. New York: Duell, Sloan and Pearce. OCLC 899039875. Buell, Thomas B. (1974). The Quiet Warrior: A Biography of Admiral Raymond A. Spruance. Boston: Little, Brown & Co. ISBN 0-316-11470-7. OCLC 1036813407. OL 5041914M. Retrieved 25 November 2020. D'Albas, Andrieu (1965). Death of a Navy: Japanese Naval Action in World War II. New York: Devin-Adair. ISBN 0-8159-5302-X. Dull, Paul S. (1978). A Battle History of the Imperial Japanese Navy, 1941–1945. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-097-1. Hornfischer, James D. (2016). The Fleet at Flood Tide: The U.S. at Total War in the Pacific, 1944–1945. Random House. ISBN 978-0-345-54872-6. Lacroix, Eric; Wells, Linton (1997). Japanese Cruisers of the Pacific War. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-311-3. Smith, Douglas V. (2006). Carrier Battles: Command Decision in Harm's Way. Annapolis, Maryland: Naval Institute Press. ISBN 1-59114-794-8. Toll, Ian W. (2015). The Conquering Tide: War in the Pacific Islands, 1942–1944. New York: W. W. Norton.
=== Acute poisoning === Exposure to high level of nitrogen dioxide may lead to inflammation of the mucous membrane and the lower and upper respiratory tracts. The symptoms of acute nitrogen dioxide poisoning is non-specific and have a semblance with ammonia gas poisoning, chlorine gas poisoning, and carbon monoxide poisoning. The symptoms also resembles that of pneumonia or viral infection and other inhalational injuries but common symptoms includes rhinitis wheezing or coughing, conjunctivitis, headache, throat irritation and dyspnea which may progress to nasal fissures, ulcerations, or perforation. The patient is usually ill-appearing and presents with hypoxemia coupled with shallow rapid breathing. Therapy is supportive and includes removal from further nitrogen dioxide exposure. Systemic symptoms include fever and anorexia. Electrocardiography and chest radiography can help in revealing diffuse, bilateral alveolar infiltrates. Chest radiography may be used in diagnosis and the baseline could be established with pulmonary function testing. There is no specific laboratory diagnostic test for acute nitrogen dioxide poisoning but analysis of arterial blood gas level, methemoglobin level, complete blood count, glucose test, lactate threshold measurement and r peripheral blood smear may be helpful in the diagnosis of nitrogen dioxide poisoning. The determination of nitrogen dioxide in urine or tissue does not establish the diagnosis, and there are technical and interpretive problems with these tests.
Because of the long-term effects of inflation, notably the significant increase of movie theater ticket prices, the list unadjusted for inflation gives far more weight to later films. The unadjusted list, while commonly found in the press, is therefore largely meaningless for comparing films widely separated in time, as many films from earlier eras will never appear on a modern unadjusted list, despite achieving higher commercial success when adjusted for price increases. To compensate for the devaluation of the currency, some charts make adjustments for inflation, but not even this practice fully addresses the issue, since ticket prices and inflation do not necessarily parallel one another. For example, in 1970, tickets cost $1.55 or about $6.68 in inflation-adjusted 2004 dollars; by 1980, prices had risen to about $2.69, a drop to $5.50 in inflation-adjusted 2004 dollars. Ticket prices have also risen at different rates of inflation around the world, further complicating the process of adjusting worldwide grosses. Another complication is release in multiple formats for which different ticket prices are charged. One notable example of this phenomenon is Avatar, which was also released in 3D and IMAX: almost two-thirds of tickets for that film were for 3D showings with an average price of $10, and about one-sixth were for IMAX showings with an average price over $14.50, compared to a 2010 average price of $7.61 for 2D films.
Sources: en.wikipedia.org
2,4,6-Triisopropylbenzenesulfonyl azide (trisyl azide) is an organic chemical used as a reagent to supply azide for electrophilic amination reactions, such as for the asymmetric synthesis of unnatural amino acids. Introduction of an azide on the α carbon of carboxylic acid derivatives using trisyl azide is an efficient alternative to electrophilic halogenation followed by nucleophilic substitution using anionic azide. Using an oxazolidinone as chiral auxiliary typically gives good induction of the stereochemistry at the α position. Subsequent reduction converts the α-azide to an α-amine.
== Production == Rabbit-skin glue is an animal glue created by prolonged boiling of animal connective tissue. Rabbit-skin glue can be bought in powder form, in little pellets, or in larger chunks. Preparation involves using the correct proportion of water to glue to achieve the correct consistency and strength. The mixture should be heated to just below the boiling point. Too much heat results in a product with reduced adhesive qualities. Manufacturers of rabbit, cow, and horse hide glues recommend dissolving at 60–63 °C (140–145 °F).
== Research == Besides treatment of ADHD, atomoxetine was under formal development by Eli Lilly and Company for the treatment of major depressive disorder, Alzheimer's disease, and Parkinson's disease. However, development for these indications was discontinued. The drug reached phase 3 clinical trials for treatment of Parkinson's disease prior to being discontinued. Though not approved for depression, atomoxetine has been studied and used off-label in the treatment of this condition, for instance as an adjunct to selective serotonin reuptake inhibitors (SSRIs) and to treat residual symptoms such as fatigue, but data are limited. It has also been studied and used to treat comorbid depression in people with ADHD. Atomoxetine has been studied in the treatment of social anxiety disorder, with mixed findings. The drug has been found to reduce anxiety symptoms in children and adolescents with ADHD and comorbid anxiety disorders. Atomoxetine may be used in those with ADHD and bipolar disorder although such use has not been well established. Some benefit has also been seen in people with ADHD and autism. As with other norepinephrine reuptake inhibitors it appears to reduce anxiety and depression symptoms, although research has focused mainly on specific patient groups such as those with concurrent ADHD or methamphetamine dependence. Atomoxetine has been studied and used in the treatment of orthostatic hypotension. It has been reported to be more effective than midodrine. The drug synergistically increased blood pressure in combination with pyridostigmine.
== Adverse effects == BCG immunization generally causes some pain and scarring at the site of injection during infancy. The mechanism of this side effect is not fully understood, however it can be mitigated by performing the vaccination later in life. Usually wealthier regions have lower scar rate among the population, such as Western Europe, unlike its Eastern counterpart, where the BCG scar is considered widespread. The insertion to the deltoid muscle is typically used because the local complication rate is smallest for that site. In most countries it is the left shoulder, although some, like Brazil, administer the vaccination to the right. Nonetheless, the buttock is an alternative site of administration because it provides better cosmetic outcomes.
=== Serotonylation === Protein serotonylation refers to the post-translational modification in which serotonin is covalently attached to glutamine residues on substrate proteins via a transamidation reaction catalyzed by TGM2. Serotonylation is a type of monoaminylation, which itself refers to the overall class of post-translational modifications involving monoamines. However, monoaminylation reactions are further classified by the individual monoamine reactant they describe (ie., serotonylation, dopaminylation, histaminylation). Serotonylation has been reported for both histone and non-histone protein substrates, and thus represents a distinct neuroepigenetic and neuroproteomic regulatory mechanism with various implications in health and disease. Since 2003, multiple studies have revealed the critical role of serotonylation in mediating a wide range of physiological processes, both in the nervous system and beyond. Serotonylation is known to contribute to several significant diseases, including neuropsychiatric disorders such as depression and schizophrenia, as well as a variety of cancers. To date, notable protein serotonylation substrates include several metabolic enzymes (GAPDH, mTOR), Rab GTPases (Rab3a, Rab27a), Rho GTPases (RhoA, Rac1, Cdc42), proteins involved in muscle contractility (⍺-actinin, SERCA2a), extracellular matrix proteins (fibronectin), neural surface proteins, and Ras, as well as histone H3.
Sources: en.wikipedia.org
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.
Mass spectrometry gives the molecular mass, which is compared with the calculated value. Reversed-phase liquid chromatography shows purity and the presence of related impurities. Peptide mapping can verify the amino acid sequence when a higher level of detail is needed.
It reports the tests the supplier performed, which may vary between laboratories and lots. Methods and acceptance criteria are not standardised across suppliers. Buyers often request the actual chromatograms and spectra rather than a summary statement.
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.