A practical reference on clinical endpoint: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-08-02 and is reviewed periodically as new material appears.
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。
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。
Thymosin alpha 1 was identified in 1977 as a component of thymosin fraction 5, a heterogeneous preparation used in early studies of thymic function. Investigators purified the active material and determined its amino acid sequence, which enabled chemical synthesis. Work in the following decades concentrated on T-cell maturation and immune reconstitution in animals and small human cohorts. Early preparations varied in composition, so results from that period are difficult to compare with studies using defined synthetic peptide.
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.
| Property | Value | Notes |
|---|---|---|
| 化学分类 | 线性肽 | 由28个氨基酸组成 |
| 分子量 | 约3108 Da | 合成版本一致 |
| 外观 | 白色至类白色粉末 | 冻干品 |
| 溶解度 | 易溶于水 | 微溶于有机溶剂 |
| 储存温度 | -20°C(冻干) | 溶解后2-8°C |
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.
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.
Knoll Pharmaceuticals was a drug development company founded by Albert Knoll and Hans Knoll in Germany in 1886. The company was taken over by German BASF in 1975, which sold it to Abbott Laboratories on 30 June 2002 for $6.9 billion. It was the developer of several drugs: Dilaudid (hydromorphone), a powerful and very water-soluble narcotic analgesic (Betäubungsmittel) introduced in 1926, as small oral tablets of a number of strengths, multipurpose (hypodermic) tablets, compounding powder, ampoules of solution for injection, and dry ampoules for reconstitution. Knoll also produced somewhat similar hydrocodone tablets named Dicodid; this drug which compares to codeine as hydromorphone compares to morphine was first synthesised and announced in Germany in 1920. The obverse sides of the oral tablets bear a stylised letter "K" and the reverse has the relevant imprint code for the medication in the locale of sale and/or number of milligrams of hydromorphone. Sibutramine, a serotonin-norepinephrine reuptake inhibitor, prescribed as an adjunct in the treatment of exogenous obesity, marketed by Abbott but withdrawn from the market in the United States and most other countries in 2010 Propafenone, an antiarrhythmic agent, marketed by Abbott. Isophan, a slightly modified version of the methamphetamine drug Pervitin, which the Nazi government in 1940 distributed to the German army and air force in an effort to win WW2.
== Mod of the Year == ModDB's Mod of the Year competition, the Golden Spanner awards, was established to recognize what it described as “inventive and high-quality” mods. Mods are chosen via a community vote and are then reviewed by staff to produce the final list of winners. The competition aims to encourage all fields of modding, with different categories such as graphics and gameplay, as well as a traditional "best mod" winner. Notable winners include Garry's Mod for Half-Life 2 in 2005, Insurgency: Modern Infantry Combat for Half-Life 2 in 2007, Black Mesa for Half-Life 2 in 2012, and Brutal Doom for Doom in 2017. Similarly, ModDB's Mod Hall of Fame retrospectively reviews mods and inducts what it judges to be the greatest mods of the year of their release. Inductees include PlayerUnknown's Battle Royale for ARMA 3 in 2014.
Rachel Frances Shaw (born 1981 or 1982) is an American actress, writer and director. She is best known for playing Bridgette Bird on the Showtime series SMILF, based on the 2015 short film of the same title, which she wrote, directed and starred in. Shaw is also known for playing Mary Jo Cacciatore on the 2010–2011 Spike TV series Blue Mountain State, and her recurring role as Shayla Nico in the first season of the USA Network television series Mr. Robot.
Sources: en.wikipedia.org
There are no FDA-approved Health Claims or Qualified Health Claims for vitamin B6. Structure/Function Claims can be made without FDA review or approval as long as there is some credible supporting science. Examples for this vitamin are "Helps support nervous system function" and "Supports healthy homocysteine metabolism."
=== Israeli stamps === Kuwait, Lebanon, Libya, and Yemen do not allow entry to people with passport stamps from Israel or whose passports have either a used or an unused Israeli visa, or where there is evidence of previous travel to Israel such as entry or exit stamps from neighbouring border posts in transit countries such as Jordan and Egypt. To circumvent this Arab League boycott of Israel, the Israeli immigration services have now mostly ceased to stamp foreign nationals' passports on either entry to or exit from Israel (unless the entry is for some work-related purposes). Since 15 January 2013, Israel no longer stamps foreign passports at Ben Gurion Airport. Passports are still (as of 22 June 2017) stamped at Erez when passing into and out of Gaza. Iran refuses admission to holders of passports containing an Israeli visa or stamp that is less than 12 months old.
== Types == Originally, seven such proteins were discovered. Of these, six (BMP2 through BMP7) belong to the Transforming growth factor beta superfamily of proteins. BMP1 is a metalloprotease. Since then, thirteen more BMPs, all of which are in the TGF-beta family, have been discovered, bringing the total to twenty. The current nomenclature only recognizes 13, as many others are put under the growth differentiation factor naming instead.
Sources: en.wikipedia.org
它不是经典的内分泌激素,而是一种免疫调节肽。其作用主要通过局部免疫细胞间的信号传递实现,而非经血液循环作用于远隔器官。
天然胸腺素α1主要从胸腺组织提取,也可在脾脏和淋巴结中检出。目前研究和临床使用的多为化学合成版本,不再依赖动物组织。
胸腺素组分5是牛胸腺提取物的粗组分,包含多种肽。胸腺素α1是其中一种被纯化和表征的单一肽,具有明确的28个氨基酸序列。
Trials differ in patient population, dose schedule, background treatment, and the endpoints used to judge success. Many are small and single-center, so random variation can dominate the reported effects.