Everything below concerns synthetic peptide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-03-02. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids whose sequence matches the amino-terminal region of prothymosin alpha. The chain is acetylated at its first residue and contains one disulfide bridge between two cysteine residues, which folds the molecule into a compact loop. Its molecular formula, C129H215N33O55, corresponds to a monoisotopic mass of roughly 3,106 daltons. Material used in laboratories is made by solid-phase synthesis rather than isolated from animal tissue.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Peptide | 28 amino acid residues |
| Molecular weight | Approximately 3108 Da | Depends on acetylation state |
| N-terminal modification | Acetylated | Affects charge and stability |
| Natural source | Fragment of thymosin beta-4 | Cleaved in vivo |
| Sequence length | 28 residues | Synthetic form matches natural |
20世纪70年代，研究者从胸腺提取物中纯化出多种小肽，Tα1是其中被较早表征的一种。最初的制备依赖组织匀浆和层析步骤，产量低且成分复杂。随着固相肽合成技术成熟，实验室和工业界能够生产与天然序列一致的合成版本。合成肽的纯度可达95%以上，并可通过反相高效液相色谱和质谱进行鉴定。这一转变使研究不再依赖动物胸腺来源。
市售的胸腺素α1通常以冻干粉形式提供，溶解后用于注射。其氨基酸组成包括多个酸性残基，因此在中性pH下带负电荷。该肽可溶于水和生理盐水，但在有机溶剂中溶解度有限。储存条件通常为冻干状态下负20摄氏度，溶解后需冷藏并避免反复冻融。常见的同义词包括胸腺肽α1、thymalfasin和Tα1。
胸腺素α1（thymosin alpha 1，Tα1）是一种由28个氨基酸组成的酸性肽，N端被乙酰化，分子量约为3108道尔顿。该肽最早从牛胸腺组织提取物中分离，属于胸腺素组分5的一个成分。其序列在不同哺乳动物中高度保守，提示其具有基本的生物学功能。名称中的“α1”指其在电泳中的迁移位置，并非表示亚型编号。它既存在于胸腺，也存在于脾脏和淋巴结等免疫组织。
Thymosin alpha-1 is a synthetic peptide of 28 amino acid residues that corresponds to a naturally occurring fragment first isolated from thymus tissue. Its chain is acetylated at the amino terminus, a modification that shields the peptide from rapid cleavage by aminopeptidases. The molecule carries a net negative charge at physiological pH and dissolves freely in water. Researchers classify it as an immune-modulating agent rather than a classical hormone, because it acts on several cell types of both the innate and the adaptive immune system.
The peptide was identified during work in the 1970s on thymosin fraction 5, a partially purified extract of calf thymus. Investigators separated that mixture and characterized individual components, one of which they named thymosin alpha-1. The same compound later received the international nonproprietary name thymalfasin. Commercial material is produced by solid-phase peptide synthesis rather than by extraction, so synthetic and natural forms share an identical sequence. Naming conventions vary across the literature, and readers should distinguish the alpha-1 peptide from other thymosins that have unrelated sequences and functions.
Biologically, the peptide is studied mainly in the context of immune cell development and regulation. It is produced in the thymus and in several other tissues, and it appears to influence the maturation and activity of T cells and other immune populations. Laboratory work describes effects on cytokine production, on the balance between T cell subsets, and on the function of dendritic cells. Much of this evidence comes from cell culture and animal models, so the extent to which the same pathways operate in humans remains an open question.
Clinical interest has centered on chronic viral hepatitis, on immune restoration in various conditions, and on use as an adjuvant intended to improve responses to vaccines. Trials have reported mixed results, and regulatory status differs sharply between countries; in some places it is a prescription product, while elsewhere it is sold without an approved therapeutic indication. Because published studies vary widely in design, population, and endpoints, comparisons across them are difficult and no single conclusion covers the whole literature.
Thymosin alpha 1 is a short peptide of 28 amino acid residues that derives from the amino terminal region of a larger precursor protein known as prothymosin alpha. The peptide carries an acetyl group on its first residue and contains no disulfide bonds or carbohydrate chains. Its sequence is highly conserved across mammalian species, which is one reason laboratories treat it as a molecule with a defined and reproducible structure rather than a variable tissue extract. The name follows an early naming convention for thymus-derived fractions and does not imply that the peptide acts as a hormone in the classical endocrine sense.
The peptide is generated in cells by cleavage of prothymosin alpha, a larger acidic protein encoded by the PTMA gene. Prothymosin alpha is expressed in many tissues, not only in the thymus, and its functions include nuclear roles in chromatin-related processes. The 28-residue fragment corresponds to the N-terminal portion of that precursor. How the cleavage occurs and how the fragment's concentration is regulated remain open questions; circulating amounts are small and difficult to measure reliably with routine assays.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
== Management == Oxygen therapy may assist with daily living. In case of idiopathic pulmonary fibrosis, certain medications like nintedanib and pirfenidone can help slow the progression. Lastly, lung transplants may help.
Karyolysis: the chromatin of the nucleus fades due to the loss of the DNA by degradation. Karyorrhexis: the shrunken nucleus fragments to complete dispersal. Pyknosis: the nucleus shrinks, and the chromatin condenses. Other typical cellular changes in necrosis include:
Current research also aims to produce these biogenic substances on a commercial level using metabolic engineering techniques. By pairing these techniques with biochemical engineering design, algae and their biogenic substances can be produced on a large scale using photobioreactors. Different system types can be used to yield different biogenic products.
27 October - 1 November The PAVN besieged Landing Zone Kate occupied by the 5th Special Forces Detachments A-233 and A-236 and their Montagnard forces and elements of the 5th Battalion, 22nd Artillery and 1st Battalion, 92nd Artillery. The base was abandoned on the night of 1 November and the US and Montagnard forces evacuated towards the nearby Bu Prang Camp.
=== Divisions === The Scientific Division works to advance the science of clinical chemistry and to apply it to the practice of clinical laboratory medicine. It is responsible for responding to the scientific and technical needs of IFCC member societies, IFCC corporate members and external agencies. It instigates and promotes theoretical and practical developments in the field of standards and standardization in clinical chemistry. The Education and Management Division provides IFCC members and the health-care community with education relevant to clinical chemistry and laboratory medicine. It administers a visiting lecturer program as well as clinical courses and workshops in molecular biology and other specialized areas. The Communications and Publications Division promotes the work of the IFCC to scientists, physicians, and global health policy makers. It also publishes the academic journal eJIFCC. The Emerging Technologies Division identifies new technologies that could be applied to laboratory medicine and explores applications for those technologies.
Sources: en.wikipedia.org
Combinatorial chemistry comprises chemical synthetic methods that make it possible to prepare a large number (tens to thousands or even millions) of compounds in a single process. These compound libraries can be made as mixtures, sets of individual compounds or chemical structures generated by computer software. Combinatorial chemistry can be used for the synthesis of small molecules and for peptides. Strategies that allow identification of useful components of the libraries are also part of combinatorial chemistry. The methods used in combinatorial chemistry are applied of outside chemistry as well.
=== Tolerance and withdrawal === Diazepam, as with other benzodiazepine drugs, can cause tolerance, physical dependence, substance use disorder, and benzodiazepine withdrawal syndrome. Withdrawal from diazepam or other benzodiazepines often leads to withdrawal symptoms similar to those seen during barbiturate or alcohol withdrawal. The higher the dose and the longer the drug is taken, the greater the risk of experiencing unpleasant withdrawal symptoms. Withdrawal symptoms can occur from standard dosages and also after short-term use, and can range from insomnia and anxiety to more serious symptoms, including seizures and psychosis. Withdrawal symptoms can sometimes resemble pre-existing conditions and be misdiagnosed. Diazepam may produce less intense withdrawal symptoms due to its long elimination half-life. Benzodiazepine treatment is recommended to be discontinued as soon as possible by a slow and gradual dose reduction regimen. Tolerance develops to the therapeutic effects of benzodiazepines; for example, tolerance occurs to the anticonvulsant effects and as a result benzodiazepines are not generally recommended for the long-term management of epilepsy. Dose increases may overcome the effects of tolerance, but tolerance may then develop to the higher dose, and adverse effects may increase. The mechanism of tolerance to benzodiazepines includes uncoupling of receptor sites, alterations in gene expression, down-regulation of receptor sites, and desensitization of receptor sites to the effect of GABA.
Reform UK's Mick Barton, the leader of Nottinghamshire County Council, has banned journalists from the Nottingham Post and its online version, Nottingham Live, from speaking to him or any of his councillors following a dispute over a story the newspaper printed about reorganising local government. A few days later Barton says that his councillors are not banned from speaking to journalists from the newspaper. 29 August – The UK government says that an Israeli delegation will not be invited to a global defence exhibition in London in September because of the Gaza war. 2025 Scottish Greens co-leadership election: Ross Greer and Gillian Mackay are elected as co-leaders of the Scottish Greens. 31 August – Conservative Party leader Kemi Badenoch says her party would remove all net zero requirements on oil and gas companies drilling in the North Sea if they win the next general election. Derek Thomson is suspended as Secretary-General of the Scottish branch of Unite the union pending an internal investigation.
In addition, Greek authorities seized a 7,000 square-metre plot of land on Paros, Greece in the Cyclades islands, which had been purchased jointly by Kaili and Giorgi. As the European Parliament convened for the first time following the scandal, on 13 December 2022, at its seat in Strasbourg, France, the offices of MEP Pietro Bartolo and Parliamentary official Mychelle Rieu were sealed by investigators. On 15 December, the European Public Prosecutor's Office (EPPO) requested that the European Parliament lift the parliamentary immunity of Eva Kaili and her fellow Greek MEP Maria Spyraki. The EPPO explained that the request was based on an investigative report from the European Anti-Fraud Office (OLAF), regarding raised "suspicion of fraud detrimental to the EU budget, in relation to the management of the parliamentary allowance." The request particularly pertained to funds paid to parliamentary assistants. On 2 January 2023, Belgian investigators submitted a request to the European Parliament to strip MEPs Marc Tarabella and Andrea Cozzolino of their parliamentary immunity. A hearing of the Parliament's Legal Affairs Committee was scheduled during the parliamentary sitting in Strasbourg on 16 January, allowing the accused MEPs to present their defence. The parties of both Tarabella and Cozzolino expressed their support for President Metsola's requests to assist the European Public Prosecutor's Office in the investigations and agreed to vote in favour of waiving their immunity. On 2 February, the European Parliament approved the request to lift their immunity.
Sources: en.wikipedia.org
== Physiology == Penicillium digitatum is a mesophilic fungus, growing from 6–7 °C (43–45 °F) to a maximum of 37 °C (99 °F), with an optimal growth temperature at 24 °C (75 °F). With respect to water activity, P. digitatum has a relatively low tolerance for osmotic stress. The minimum water activity required for growth at 25 °C (77 °F) is 0.90, at 37 °C (99 °F) is 0.95 and at 5 °C (41 °F) is 0.99. Germination does not occur at a water activity of 0.87. In terms of chemicals that influence fungal growth, the minimum growth inhibitory concentration of sorbic acid is 0.02–0.025% at a pH of 4.7 and 0.06–0.08% at a pH of 5.5. Thiamine, on the other hand, has been observed to accelerate fungal growth, with the effect being co-metabolically enhanced in the presence of tyrosine, casein, or zinc metal. In terms of carbon nutrition, maltose, acetic acid, oxalic acid, and tartaric acid support little, if any, growth. However, glucose, fructose, sucrose, galactose, citric acid, and malic acid all maintain fungal growth. Production of ethylene via the citric acid cycle has been observed in static cultures, and is suggested to be connected to mycelial development. Addition of methionine inhibits such cultures, but can be utilized for the production of ethylene following a lag phase in shake cultures (cultures mixed in liquid media with a shaker). The production observed in shake cultures can be inhibited by actinomycin D and cycloheximide, and modulated by inorganic phosphate.
As of 2019, there were an estimated 72,000 centenarians living in the U.S.; the 2020 census officially counted 80,139, and the 2010 census had 53,364. However, the U.S. Census Bureau claimed in 1999 that as many as a third of people stating their age as over 100 might be exaggerating. In the United States, centenarians may request a letter of congratulation from the president of the United States to mark their longevity. Strom Thurmond became the first sitting Senator to reach 100 on 5 December 2002. Jimmy Carter became the first former president to reach the age of 100 on 1 October 2024. Today also presents a segment honoring centenarians and older, sponsored by Smuckers. The tradition was created in 1983 by weather presenter Willard Scott, and is now presented by his successor Al Roker. In the state of New Mexico, centenarians have been exempt from state income tax since tax year 2002, if they are not dependents of another taxpayer.
The pericardium (pl. pericardia), also called pericardial sac, is a fluid filled sac containing the heart and the roots of the great vessels. It has three layers, an outer layer made of strong inelastic connective tissue (fibrous pericardium), and a double-layered inner membrane serous membrane (serous pericardium), between which the pericardial fluid is contained. It encloses the pericardial cavity, which contains pericardial fluid, and defines the middle mediastinum. It separates the heart from interference of other structures, protects it against infection and blunt trauma, and lubricates the heart's movements.
Sources: en.wikipedia.org
It corresponds to the first 28 amino acids of thymosin beta-4, a larger protein found in many tissues. The fragment is acetylated at its N-terminus and is produced synthetically for research and pharmaceutical use. Synthetic and natural forms share the same sequence.
It is usually described as an immunomodulatory peptide rather than a classical hormone. It does not travel to a single distant organ in the manner of an endocrine hormone. Classification varies across sources, and some texts group it with thymic peptides generally.
The broad outline involves immune cell activation, but the specific molecular steps remain under investigation. Different studies report effects on dendritic cells, T cells, and natural killer cells. No single receptor has been confirmed as the sole mediator.
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.