This is a working overview of lyophilized powder, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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.
临床研究将Tα1用于慢性病毒感染、肿瘤辅助治疗和疫苗佐剂等场景。部分试验报告了免疫学指标改善，但临床终点获益在不同研究中并不一致。系统综述指出，研究间在人群、剂量和联合方案上差异较大，难以汇总结论。因此，Tα1的确切临床地位仍属开放问题，需要更多高质量随机对照试验来澄清。其机制研究也需从体外实验向体内模型推进。
胸腺素α1对免疫系统的影响涉及多种细胞类型。研究表明，它可促进未成熟T细胞向成熟T细胞分化，并增强T细胞对抗原刺激的增殖反应。树突状细胞在Tα1存在下表达更高水平的共刺激分子，从而更有效地呈递抗原。此外，自然杀伤细胞的活性也观察到上升。这些效应并非直接杀伤病原体，而是调节宿主免疫应答的强度与方向。
| Property | Value | Notes |
|---|---|---|
| Molecular mass | Approximately 3,108 Da | Consistent with a 28-residue acetylated peptide |
| Residue count | 28 | Corresponds to the amino terminal region of prothymosin alpha |
| Appearance of dry powder | White to off-white solid | Slight variation between lots is normal |
| Solubility class | Freely soluble in water | Low solubility in most organic solvents |
| Common synonyms | Thymosin alpha 1, T alpha 1 | The numeral reflects an early fraction numbering scheme |
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。
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.
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.
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.
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.
will begin restricting travel from India starting May 4 due to rising cases of the Lineage B.1.617 which originated in the latter country. Michigan reports its first case of Lineage B.1.617, first discovered in India, in a person from Clinton County.
=== In popular culture === The movie A Civil Action, starring John Travolta, was based on the Grace groundwater contamination lawsuits in Woburn, Massachusetts. The PBS television show P.O.V., which highlights independent films, in August 2007 premiered the movie Libby, Montana which documents the thousands of people in Libby, Montana, that have been exposed to and are suffering the effects of asbestos exposure. The show also discusses the criminal indictments of many Grace executives for covering up asbestos related illnesses and deaths. PBS also aired Dust to Dust, a documentary produced by Michael Brown Productions, Inc. in 2002. Dust to Dust reports on the more than 200 people who have died from asbestos exposure in Libby, Montana. The film focuses on the plights of several of these individuals and the damage done over almost 30 years while the mine was operated by W. R. Grace. NPR aired a piece on All Things Considered discussing the criminal charges against W. R. Grace. A U.S. attorney general alleges that the company and managers of the mine in Libby, Montana, knew about the dangers of the asbestos they were dumping into the air for over 20 years. On February 19, 2008, the NPR-produced radio show Here and Now broadcast a story about the film Libby, Montana, which details the asbestos contamination in the town of that name. On April 22, 2009, the television and radio program Democracy Now! broadcast two segments on the trial of W. R. Grace and some of its employees related to the asbestos contamination in Libby, Montana.
==== Mixed apnea ==== Some people with sleep apnea have a combination of both types; its prevalence ranges from 0.56% to 18%. The condition, also called treatment-emergent central apnea, is generally detected when obstructive sleep apnea is treated with CPAP and central sleep apnea emerges. The exact mechanism of the loss of central respiratory drive during sleep in OSA is unknown but is most likely related to incorrect settings of the CPAP treatment and other medical conditions the person has.
==== Respiratory zone ==== The conducting zone of the respiratory tract ends at the terminal bronchioles when they branch into the respiratory bronchioles. This marks the beginning of the terminal respiratory unit called the acinus which includes the respiratory bronchioles, the alveolar ducts, alveolar sacs, and alveoli. An acinus measures up to 10 mm in diameter. A primary pulmonary lobule is the part of the lung distal to the respiratory bronchiole. Thus, it includes the alveolar ducts, sacs, and alveoli but not the respiratory bronchioles. The unit described as the secondary pulmonary lobule is the lobule most referred to as the pulmonary lobule or respiratory lobule. This lobule is a discrete unit that is the smallest component of the lung that can be seen without aid. The secondary pulmonary lobule is likely to be made up of between 30 and 50 primary lobules. The lobule is supplied by a terminal bronchiole that branches into respiratory bronchioles. The respiratory bronchioles supply the alveoli in each acinus and is accompanied by a pulmonary artery branch. Each lobule is enclosed by an interlobular septum. Each acinus is incompletely separated by an intralobular septum. The respiratory bronchiole gives rise to the alveolar ducts that lead to the alveolar sacs, which contain two or more alveoli. The walls of the alveoli are extremely thin allowing a fast rate of diffusion. The alveoli have interconnecting small air passages in their walls known as the pores of Kohn.
A compound is a pure chemical substance composed of more than one element. The properties of a compound bear little similarity to those of its elements. The standard nomenclature of compounds is set by the International Union of Pure and Applied Chemistry (IUPAC). Organic compounds are named according to the organic nomenclature system. The names for inorganic compounds are created according to the inorganic nomenclature system. When a compound has more than one component, then they are divided into two classes, the electropositive and the electronegative components. In addition the Chemical Abstracts Service (CAS) has devised a method to index chemical substances. In this scheme each chemical substance is identifiable by a number known as its CAS registry number.
Sources: en.wikipedia.org
Thirlby's Anderson was also highlighted, such as by Berkshire for carrying the film's emotional story and said, "one of the film's true thrills comes in watching Thirlby effortlessly balance the conflict between a Judge's merciless duties and a psychic's compassionate understanding." The New Statesman's Laura Sneddon noted that Dredd passed the Bechdel test, lacking in sexism or misogyny and positively portraying female characters who are no weaker, more sexualised or shown less than their male counterparts. Sneddon described Anderson as repeatedly shown to have power over men who underestimate her, while Ma-Ma displays more intelligence and sadism than any of her male gang members, and neither woman interacts with the other on the basis of their gender. Many US newspaper critics were less taken with the film. Mark Olsen of the Los Angeles Times called it "a clunk-headed action picture" that "simply becomes a monotonous series of bad-guy confrontations". Frank Lovece of Newsday described it as a "soullessly gritty" film, which apart from one believable scene involving Thirlby, is "all tough-guy talk and humorless cynicism". Stephen Whitty of The Star-Ledger called it a "gray and ugly film", said that there was little to draw viewers in, and wrote that apart from the drug-induced slow-motion sequences, the film offers nothing new.
== External links == The Macromolecular Structure Database (MSD) at the European Bioinformatics Institute (EBI) – Serves a list of the Probable Quaternary Structure (PQS) for every protein in the Protein Data Bank (PDB). PQS server – PQS has not been updated since August 2009 PISA – The Protein Interfaces, Surfaces and Assemblies server at the MSD. EPPIC – Evolutionary Protein–Protein Interface Classification: evolutionary assessment of interfaces in crystal structures 3D complex[link removed] – Structural classification of protein complexes Proteopedia – Proteopedia Home Page The collaborative, 3D encyclopedia of proteins and other molecules. PDBWiki – PDBWiki Home Page – a website for community annotation of PDB structures. ProtCID – ProtCID—a database of similar protein–protein interfaces in crystal structures of homologous proteins.
{\displaystyle {\begin{aligned}&{\frac {dS}{dt}}=-{\frac {\beta (t)IS}{N}}-v(t)S,\\[6pt]&{\frac {dI}{dt}}={\frac {\beta (t)IS}{N}}-\gamma (t)I,\\[6pt]&{\frac {dR}{dt}}=\gamma (t)I,\\[6pt]&{\frac {dV}{dt}}=v(t)S,\end{aligned}}}
Lori stated that he would be taking a sabbatical from the program until he recovers. She blamed the stroke on Bakker's hard work on his show and wrote that he had described the criticism against him as "the most vicious attack that he has ever experienced". Bakker returned to his program for the first time following his stroke on July 8, 2020. On June 23, 2021, Missouri Attorney General Eric Schmitt announced the settlement of the state's lawsuit against Bakker. Bakker and Morningside Church would be prohibited from saying silver solution could "diagnose, prevent, mitigate, treat, or cure any disease or illness". Restitution of about $157,000 would also be paid to those who bought silver solution between February 12, 2020, and March 10, 2020.
Sources: en.wikipedia.org
Due to their numerous sources indoors, concentrations of VOCs indoors are consistently higher (up to ten times higher) than outdoors. VOCs are emitted by thousands of indoor products. Examples include: paints, varnishes, waxes and lacquers, paint strippers, cleaning and personal care products, pesticides, building materials and furnishings, office equipment such as copiers and printers, correction fluids and carbonless copy paper, graphics and craft materials including glues and adhesives, permanent markers, and photographic solutions. Human activities such as cooking and cleaning can also emit VOCs. Cooking can release long-chain aldehydes and alkanes when oil is heated and terpenes can be released when spices are prepared and/or cooked. Cleaning products contain a range of VOCs, including monoterpenes, sesquiterpenes, alcohols and esters. Once released into the air, VOCs can undergo reactions with ozone and hydroxyl radicals to produce other VOCs, such as formaldehyde. Some VOCs are emitted directly indoors, and some are formed through the subsequent chemical reactions. The total concentration of all VOCs (TVOC) indoors can be up to five times higher than that of outdoor levels. New buildings experience particularly high levels of VOC off-gassing indoors because of the abundant new materials (building materials, fittings, surface coverings and treatments such as glues, paints and sealants) exposed to the indoor air, emitting multiple VOC gases.
== Regulation == AADC regulation, especially as it relates to L-DOPA decarboxylation, has been studied extensively. AADC has several conserved protein kinase A (PKA) and protein kinase G recognition sites, with residues S220, S336, S359, T320, and S429 all as potential phosphate acceptors. In vitro studies have confirmed PKA and PKG can both phosphorylate AADC, causing a significant increase in activity. In addition, dopamine receptor antagonists have been shown to increase AADC activity in rodent models, while activation of some dopamine receptors suppresses AADC activity. Such receptor-mediated regulation is biphasic, with an initial short term activation followed by long term activation. The short term activation is thought to proceed through kinase activation and subsequent phosphorylation of AADC, while the sensitivity of long term activation to protein translation inhibitors suggests regulation of mRNA transcription.
The US Navy dispatched two naval battle groups built around the aircraft carriers USS Dwight D. Eisenhower and USS Independence to the Gulf, where they were ready by 8 August. The US sent the battleships USS Missouri and USS Wisconsin. 48 US Air Force F-15s from the 1st Fighter Wing at Langley Air Force Base, Virginia, landed in Saudi Arabia and commenced round-the-clock air patrols of the Saudi–Kuwait–Iraq border to discourage Iraqi military advances. They were joined by 36 F-15 A-Ds from the 36th Tactical Fighter Wing at Bitburg, Germany. The Bitburg contingent was based at Al Kharj Air Base. The 36th TFW would be responsible for 11 confirmed Iraqi Air Force aircraft shot down during the war. Two Air National Guard units were stationed at Al Kharj Air Base, the South Carolina Air National Guard's 169th Fighter Wing flew bombing missions with 24 F-16s flying 2,000 combat missions and dropping four million pounds (1,800,000 kilograms; 1,800 metric tons) of munitions, and the New York Air National Guard's 174th Fighter Wing from Syracuse flew 24 F-16s on bombing missions. Military buildup continued, reaching 543,000 troops, twice that used in the 2003 invasion. Much of the material was airlifted or carried to the staging areas via fast sealift ships, allowing a quick buildup. Amphibious exercises were carried out in the Gulf, including Operation Imminent Thunder, which involved the USS Midway and 15 other ships, 1,100 aircraft, and a thousand Marines.
Ankylosing spondylitis (AS) is a systemic rheumatic disease, meaning it affects the entire body. 1–2% of individuals with the HLA-B27 genotype develop the disease. Tumor necrosis factor (TNF) and interleukin 1 (IL-1) are also implicated in ankylosing spondylitis. Autoantibodies specific for AS have not been identified. Anti-neutrophil cytoplasmic antibodies (ANCAs) are associated with AS, but do not correlate with disease severity. Single nucleotide polymorphism (SNP) A/G variant rs10440635 is close to the PTGER4 gene on human chromosome 5 has been associated with an increased number of cases of AS in a population recruited from the United Kingdom, Australia, and Canada. The PTGER4 gene codes for the prostaglandin EP4 receptor, one of four receptors for prostaglandin E2. Activation of EP4 promotes bone remodeling and deposition (see prostaglandin EP4 receptor § Bone) and EP4 is highly expressed at vertebral column sites involved in AS. These findings suggest that excessive EP4 activation contributes to pathological bone remodeling and deposition in AS and that the A/G variant rs10440635a of PTGER4 predisposes individuals to this disease, possibly by influencing EP4's production or expression pattern. The association of AS with HLA-B27 suggests the condition involves CD8 T cells, which interact with HLA-B. This interaction is not proven to involve a self-antigen, and at least in the related reactive arthritis, which follows infections, the antigens involved are likely to be derived from intracellular microorganisms.
== Selected awards and honors == 2023 Christian B. Anfinsen Award 2021 American Chemical Society Nakanishi Prize 2018 Nirit and Michael Shaoul Fellow, Sackler Institute of Advanced Studies, Tel Aviv University 2016 Fellow of the International Society of Magnetic Resonance (ISMAR) 2014 Günther Laukien Prize, Experimental NMR Conference 2012 Protein Society Irving Sigal Young Investigator Award 2010 Founders Medal, International Council on Magnetic Resonance in Biological Systems 2010 Fellow of the American Association for the Advancement of Science 2003 Pure Chemistry Award, American Chemical Society 2002 Alfred P. Sloan Research Fellow, Sloan Foundation 2001 CAREER Award, National Science Foundation 1999 Beckman Young Investigator Award, Beckman Foundation
Sources: en.wikipedia.org
The name reflects an early convention for naming thymus-derived fractions. The peptide is characterized and measured as a defined molecule, and it does not operate through a single classical endocrine axis.
它促进未成熟T细胞分化并增强成熟T细胞的增殖与细胞因子分泌。这些作用有助于放大抗原特异性免疫应答。
目前认为它可能通过Toll样受体等模式识别受体传递信号，但精确的受体身份和结合机制尚未完全阐明。
不同试验在患者选择、给药方案、联合治疗和终点定义上差异很大。这些异质性使得跨研究比较困难，结论难以统一。