Everything below concerns thymalfasin. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-03-11. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
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.
| 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 |
Lyophilized thymosin alpha 1 is typically stored refrigerated at 2 to 8 degrees Celsius and kept away from light. Reconstituted solutions are less stable and are usually used promptly after preparation. Repeated freeze-thaw cycles are avoided because they can promote aggregation and loss of activity. The peptide adsorbs to some plastic and glass surfaces, so a carrier protein is often added to dilute working solutions. Manufacturer instructions and published protocols both govern handling.
Identity and purity testing for thymosin alpha 1 relies mainly on reversed-phase high-performance liquid chromatography and mass spectrometry. Chromatography separates the parent peptide from truncated or modified variants, while mass spectrometry confirms the expected molecular mass. Amino acid analysis and peptide mapping provide additional sequence confirmation. Counterion content, water content, and residual solvents are measured separately as part of specification testing. No single method captures every attribute, so laboratories combine several techniques.
The peptide lacks cysteine, methionine, and tryptophan, so disulfide scrambling and sulfur oxidation are not major degradation routes. Instead, aspartate residues can undergo isomerization or cyclization to succinimide intermediates, generating isoaspartate variants. Hydrolysis of peptide bonds also occurs slowly in solution. These changes may reduce biological activity even when the main peak remains detectable. Stability studies therefore track both potency and the appearance of related substances.
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。
The activity of this peptide is generally described as immunomodulatory rather than directly antimicrobial. Experimental work links it to signaling through certain Toll-like receptors on dendritic cells and to downstream maturation of antigen-presenting cells. Reported effects include expansion of T cell subsets, shifts in cytokine profiles, and increased natural killer cell activity. These observations come largely from cell culture and animal models, and the precise receptor-level events in humans remain incompletely characterized.
The compound has been investigated as an adjunct in chronic viral hepatitis and as a vaccine adjuvant, with results that vary by study design and population. Regulators in some countries have approved a synthetic form for specific indications, while other agencies have not. Whether the peptide produces consistent clinical benefit across diverse patient groups is still an open question, and many trials have been small. Its status is therefore best described as investigational in many contexts and established only narrowly.
The name itself causes confusion, because several unrelated thymic peptides share the thymosin label. Thymosin beta-4, for example, is a different molecule with different functions. Naming conventions in the literature also mix descriptive research terms with assigned nonproprietary names, so a reader should confirm which entity a given paper addresses. Clarifying that point is usually the first step in interpreting any claim about this peptide.
== Other uses == The nutrition-rich nature of yeast extract lends it to a variety of uses. It was historically popular as a vitamin supplement for humans. Rich in proteins and nucleotides, it currently finds use in animal feed and microbiology (see yeast extract agar) as nutritional supplements. It also finds use in cosmetics and skincare products due to its alleged moisturizing and antioxidant properties.
The death penalty response by Shanmugam during the BBC interview was well-received and supported by many members of the public on social media, who also voiced their support for capital punishment for drugs in Singapore. In light of the execution of Abdul Rahim Shapiee (and his accomplice), Pritam Singh, opposition leader of Parliament and chairman of Workers' Party, wrote to Singapore newspaper Today to express his support for the death penalty for drug crimes in Singapore and the execution of drug traffickers. Singh nonetheless argued that there should be changes made to rectify the shortcomings in determining the extent of one's cooperation with the authorities during investigations before sentencing, citing cases of traffickers receiving death sentences before courts decided they were couriers and could sentence them for life, as well as cases like Abdul Rahim's, who was sentenced to death despite being a courier and having provided substantive assistance. Singh also expressed concern about the need to curb the frequent abuse of court processes by drug traffickers and their lawyers. The Ministry of Home Affairs (MHA) revealed that from 2013 to early 2022, certificates of substantive assistance were issued to 82 out of 104 drug traffickers regardless of nationality, while there were 14 out of the remaining 22 sentenced to death and the other eight traffickers sentenced to life imprisonment due to mental illnesses.
Another factor that critics have focused on is Jung's use of anthropological 'stage theory' and colonial conceptions of history and the psychology of pre-modern cultures. This theory postulated various stages that human cultures go through from hunter-gathering to settled villages and complex hierarchical civilizations. While it has been subject to criticism the theory has been adopted by numerous contemporary anthropologists. Consequently, given the continuing relevance of anthropological stage theory, it has been argued that Jung's anthropological thought, despite elements of colonial racism, nevertheless still offers researchers an evidence-based paradigm for psychological approaches to evolutionary anthropology. As one scholar has commented, we should not, based on a simplistic analysis of the anthropological thought that inspired Jung, throw 'the anthropological baby out with the colonial bathwater.' The same author argues that Jung's anthropological theories provide an explanatorily powerful framework for analysing anthropological field data and particularly that associated with ritual life, shamanism, altered states of consciousness and traditional psychedelic plant use.
=== Paramount and CBS partnership === On August 11, 2025, the UFC announced a seven-year media rights agreement with Paramount Skydance Corporation worth $7.7 billion. Paramount+ will exclusively stream all events for seven years, starting in 2026. Some numbered events will also air on CBS. The agreement will allow the UFC to move away from pay-per-view as events will stream on Paramount+ at no additional cost. All 13 of the UFC's flagship events and 30 Fight Nights a year will be streamed on the Paramount+ service. UFC CEO and President Dana White announced the UFC would produce four big events per year on CBS, and that the UFC's planned card for the White House on June 14th, 2026 would be one of those events.
Sources: en.wikipedia.org
Jie Jack Lie et al. made use of the Stille-Kelly coupling in their synthesis of a variety of benzo[4,5]furopyridines ring systems. They invoke a three-step process, involving a Buchwald-Hartwig amination, another palladium-catalyzed coupling reaction, followed by an intramolecular Stille-Kelly coupling. Note that the aryl-iodide bond will oxidatively add to the palladium faster than either of the aryl-bromide bonds.
==== Elimination ==== Alvimopan undergoes 35% renal excretion and greater than 50% biliary excretion. Drug metabolized by intestinal flora is excreted in the feces. Alvimopan's half-life of elimination is 10 to 17 hours, while that of the gut metabolite is 10 to 18 hours.
A third, only marginally related concept was proposed in 1923 by Gilbert N. Lewis, which includes reactions with acid–base characteristics that do not involve a proton transfer. A Lewis acid is a species that accepts a pair of electrons from another species; in other words, it is an electron pair acceptor. Brønsted acid–base reactions are proton transfer reactions while Lewis acid–base reactions are electron pair transfers. Many Lewis acids are not Brønsted–Lowry acids. Contrast how the following reactions are described in terms of acid–base chemistry:
Sources: en.wikipedia.org
The tree was created by maximum likelihood analysis without bootstrap: consequently accuracy is traded off for size and many phylum level clades are not correctly resolved (such as the Firmicutes). (Eukaryotes not present in analysis). This phylogeny is a summary of the 16S rRNA based LTP_07_2026 and contains all type species with validly published names up to July 2026. Branching order of bacterial phyla (Woese, 1987) Branching order of bacterial phyla (Gupta, 2001) Branching order of bacterial phyla (Cavalier-Smith, 2002) Branching order of bacterial phyla (Rappe and Giovanoni, 2003) Branching order of bacterial phyla (Battistuzzi et al., 2004) Branching order of bacterial phyla (Ciccarelli et al., 2006) Branching order of bacterial phyla (Genome Taxonomy Database, 2018) Bacterial phyla List of Archaea genera List of bacteria genera List of bacterial orders LPSN, list of accepted bacterial and archaeal names http://www.arb-silva.de/projects/living-tree/
Conversely, venlafaxine robustly inhibited the SERT but only inhibited the NET at high doses. Atomoxetine has been found to act as an NMDA receptor antagonist in rat cortical neurons at therapeutic concentrations (IC50Tooltip half-maximal inhibitory concentration = ~3,000 nM). It causes a use-dependent open-channel block and its binding site overlaps with the Mg2+ binding site. Atomoxetine's ability to increase prefrontal cortex firing rate in anesthetized rats could not be blocked by D1 or α1-adrenergic receptor antagonists, but could be potentiated by NMDA or an α2-adrenergic receptor antagonist, suggesting a glutaminergic mechanism. In Sprague Dawley rats, atomoxetine reduces NR2B protein content without altering transcript levels. Aberrant glutamate and NMDA receptor function have been implicated in the etiology of ADHD. Atomoxetine also reversibly inhibits G protein-coupled inwardly rectifying potassium channel (GIRK) currents in Xenopus oocytes in a concentration-dependent, voltage-independent, and time-independent manner. Kir3.1/3.2 ion channels are opened downstream of M2, α2, D2, and A1 stimulation, as well as other Gi-coupled receptors. Therapeutic concentrations of atomoxetine are within range of interacting with GIRKs, especially in CYP2D6 poor metabolizers. It is not known whether this contributes to the therapeutic effects of atomoxetine in ADHD. It has been found to inhibit voltage-gated sodium channels.
== History == Gemtuzumab ozogamicin was created in a collaboration between Celltech and Wyeth that began in 1991. The same collaboration later produced inotuzumab ozogamicin. Celltech was acquired by UCB in 2004 and Wyeth was acquired by Pfizer in 2009. In the United States, gemtuzumab ozogamicin was approved under an accelerated-approval process by the FDA in 2000, for use in patients over the age of 60 with relapsed acute myelogenous leukemia (AML); or those who are not considered candidates for standard chemotherapy. The accelerated approval was based on the surrogate endpoint of response rate. It was the first antibody-drug conjugate to be approved. Within the first year after approval, the FDA required a black box warning be added to gemtuzumab packaging. The drug was noted to increase the risk of veno-occlusive disease in the absence of bone marrow transplantation. Later the onset of VOD was shown to occur at increased frequency in gemtuzumab patients even following bone marrow transplantation. The drug was discussed in a 2008 JAMA article, which criticized the inadequacy of postmarketing surveillance of biologic agents. A randomized Phase III comparative controlled trial (SWOG S0106) was initiated in 2004, by Wyeth in accordance with the FDA accelerated-approval process. The study was stopped on August 20, 2009, prior to completion due to worrisome outcomes. Among the patients evaluated for early toxicity, fatal toxicity rate was significantly higher in the gemtuzumab combination therapy group vs the standard therapy group.
She concluded "I find it somewhat difficult to believe that, in a single raid, we find two new forms of Captagon." Videos compiled by the Israeli government of the Hamas attack—cobbled together from cell phones, GoPros, as well as car and surveillance cameras—allege that at least some of the militants were under the influence of the drug. Rose also said that "Fighters might have taken cocaine right before, or captagon, or no substances at all. Some might have taken caffeine, some may be sleep deprived...but there's no way that captagon was a factor to blame in the violence and atrocities that we witnessed on October 7".
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.
Thymosin fraction 5 is a mixture of many peptides obtained from thymus tissue, while thymosin alpha 1 is a single defined 28-residue molecule. The two names appear together in older literature because the purified peptide was first obtained from that mixture.