The short version of thymalfasin fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-12-27. Anything still debated is marked as such rather than presented as settled.
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。
Stability depends on temperature, pH, and the number of freeze-thaw events the sample has experienced. Freeze-dried material is commonly held at -20 °C or colder, while reconstituted liquid is kept cold and used within a short window. Extreme pH and prolonged light exposure can promote deamidation, oxidation, or aggregation, particularly at asparagine and methionine positions. Adsorption to container walls can lower the measured concentration of a dilute solution even when the peptide molecules themselves remain intact.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or chemically modified byproducts. Mass spectrometry confirms the expected molecular mass and can indicate acetylation state or sequence errors. Amino acid analysis and peptide mapping supply complementary sequence-level information, while endotoxin testing is relevant for preparations intended for cell or animal work. Purity figures reported by suppliers refer to the method used and are not directly comparable across laboratories unless conditions are stated.
| 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 |
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.
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.
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 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.
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.
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.
Inclusion body myositis (IBM) () (sometimes called sporadic inclusion body myositis, sIBM) is the most common inflammatory muscle disease in older adults. The disease is characterized by slowly progressive weakness and wasting of both proximal muscles (located on or close to the torso) and distal muscles (close to hands or feet), most apparent in the finger flexors and knee extensors. IBM is often confused with an entirely different class of diseases, called hereditary inclusion body myopathies (hIBM). The "M" in hIBM is an abbreviation for "myopathy" while the "M" in IBM is for "myositis". In IBM, two processes appear to occur in the muscles in parallel, one autoimmune and the other degenerative. Inflammation is evident from the invasion of muscle fibers by immune cells. Degeneration is characterized by the appearance of holes, deposits of abnormal proteins, and filamentous inclusions in the muscle fibers. sIBM is a rare disease, with a prevalence ranging from 1 to 71 individuals per million. Weakness comes on slowly (over months to years) in an asymmetric manner and progresses steadily, leading to severe weakness and wasting of arm and leg muscles. IBM is more common in men than women. Patients may become unable to perform activities of daily living and most require assistive devices within 5 to 10 years of symptom onset. sIBM does not significantly affect life expectancy, although death related to malnutrition and respiratory failure can occur. The risk of serious injury due to falls is increased. There is no effective treatment for the disease as of 2019.
== Challenges and future outlook == The commercial viability of Pakistan’s oil potential remains uncertain, constrained by geopolitical volatility, investor hesitation, and logistical hurdles. Governance remains a concern—including equitable integration of provincial stakeholders and transparency in licensing. There is anticipation for the first shipment of U.S. crude oil to Pakistan, likely in October 2025 via Cnergyico and Vitol, symbolizing the deal's early implementation. The potential of exports to India remains speculative, heavily contingent on regional diplomacy and stability.
== History == Medea was first performed in 431 BC at the City Dionysia festival. Here every year, three tragedians competed against each other, each writing a tetralogy of three tragedies and a satyr play (alongside Medea were Philoctetes, Dictys and the satyr play Theristai). In 431 the competition was among Euphorion (the son of famed playwright Aeschylus), Sophocles (Euripides's main rival) and Euripides. Euphorion won, and Euripides placed third (and last). Medea has survived the transplants of culture and time and continues to captivate audiences with its riveting power. The play's influence can be seen in the works of later playwrights, such as William Shakespeare. While Medea is considered one of the great plays of the Western canon, Euripides's place in the competition suggests that his first audience might not have responded so favorably. A scholium to line 264 of the play suggests that Medea's children were traditionally killed by the Corinthians after her escape; so Euripides's apparent invention of the filicide might have offended, as his first treatment of the Hippolytus myth did. That Euripides and others took liberties with Medea's story may be inferred from the 1st-century-BC historian Diodorus Siculus: "Speaking generally, it is because of the desire of the tragic poets for the marvellous that so varied and inconsistent an account of Medea has been given out." A common urban legend claimed that Euripides put the blame on Medea because the Corinthians had bribed him with a sum of five talents.
In September 2024, Israel intensified its operations with two waves of electronic device attacks targeting Hezbollah's communication systems, and later assassinated the group's leading figures, including Secretary-General Hassan Nasrallah, and his successor, Hashem Safieddine. On 1 October, the Israeli military began an invasion of southern Lebanon, although it had been conducting limited ground operations for some time. Israeli operations led to the significant dismantling of Hezbollah's military infrastructure in southern Lebanon and the destruction of a large portion of its missile stockpile. A 60-day ceasefire agreement was brokered and took effect on 27 November 2024. The ceasefire required Hezbollah to move its fighters north of the Litani River, approximately 30 kilometres (19 miles) from the Israeli border, while Israel began withdrawing its forces from southern Lebanon. The Lebanese Army was tasked with deploying around 5,000 soldiers to monitor the situation and maintain peace in the region. The ceasefire is being monitored by a panel of five countries, led by the United States, though Israel retains the right to strike at immediate threats in Lebanon during this period. The ceasefire was extended to 18 February 2025, at which time the Israel Defense Forces (IDF) withdrew from most of southern Lebanon. Airstrikes resumed on 2 March 2026 between Hezbollah and Israel following the 2026 Iran war and the killing of Ali Khamenei. On 16 April, President Trump announced that Israel and Lebanon agreed to a 10-day truce.
Sources: en.wikipedia.org
Large randomised controlled trials have shown that dapagliflozin significantly reduces worsening heart failure and heart failure hospitalisation across the spectrum of heart failure, including patients with reduced ejection fraction (LVEF <40%), mildly reduced ejection fraction (LVEF 41–49%) and preserved ejection fraction (LVEF ≥50%). Research shows that early initiation during hospitalization for acute heart failure appears safe in stable patients. Combined results of multiple trials also found that starting SGLT2 inhibitors in the hospital significantly lowers the risk of death from heart problems and prevents heart failure from getting worse. Dapagliflozin and other SGLT2 inhibitors may reduce hospitalisation for heart failure in Type 2 diabetic patients, with or without atherosclerotic cardiovascular disease,however evidence across these patient groups remains incomplete. Some meta-analyses and cohort studies have demonstrated consistent efficacy among SGLT2 inhibitors in reducing specific heart failure hospitalization, but there are no direct and definitive studies indicating the superiority of dapagliflozin over other SGLT2 inhibitors like empagliflozin and further studies are needed to support this claim In the European Union, dapagliflozin is indicated in adults for treatment of:
N-methyl putrescine then undergoes deamination into 4-methylaminobutanal by the N-methyl putrescine oxidase (MPO) enzyme, 4-methylaminobutanal then spontaneously cyclize into N-methyl-Δ1-pyrrollidium cation. The final step in the synthesis of nicotine is the coupling between N-methyl-Δ1-pyrrollidium cation and nicotinic acid. Although studies conclude some form of coupling between the two component structures, the definite process and mechanism remains undetermined. The current agreed theory involves the conversion of nicotinic acid into 2,5-dihydropyridine through 3,6-dihydronicotinic acid. The 2,5-dihydropyridine intermediate would then react with N-methyl-Δ1-pyrrollidium cation to form enantiomerically pure (−)-nicotine.
Despite the underlying notion of the lab as a confined space for experts, the term "laboratory" is also increasingly applied to workshop spaces such as Living Labs, Fab Labs, or Hackerspaces, in which people meet to work on societal problems or make prototypes, working collaboratively or sharing resources. This development is inspired by new, participatory approaches to science and innovation and relies on user-centred design methods and concepts like Open innovation or User innovation. One distinctive feature of work in Open Labs is the phenomenon of translation, driven by the different backgrounds and levels of expertise of the people involved.
=== Pharmacokinetics === Esketamine is eliminated from the human body more quickly than arketamine (R(–)-ketamine) or racemic ketamine, although arketamine slows the elimination of esketamine. The half-life of esketamine was found to be approximately 5 hours. When administered intranasally, esketamine's bioavailability is approximately 30–50%.
=== Intra-city on-demand delivery === SF Intra-City focuses on on-demand delivery services, with end-to-end instant delivery throughout the city as its core business, providing delivery services for merchants, consumers, couriers and partners. With the rise of e-commerce and live streaming in China, it launched on-demand delivery services combined with e-commerce live streaming. The company was listed on the Hong Kong Stock Exchange in 2021 and was included in the Hong Kong Stock Connect in September 2024.
Sources: en.wikipedia.org
=== Airspheres === These are vast, brown dwarf-sized bubbles of atmosphere enclosed by force fields, and (presumably) set up by an ancient advanced race at least one and a half billion years ago (see: Look to Windward). There is only minimal gravity within an airsphere. They are illuminated by moon-sized orbiting planetoids that emit enormous light beams. Citizens of the Culture live there only very occasionally as guests, usually to study the complex ecosystem of the airspheres and the dominant life-forms: the "dirigible behemothaurs" and "gigalithine lenticular entities", which may be described as inscrutable, ancient intelligences looking similar to a cross between gigantic blimps and whales. The airspheres slowly migrate around the galaxy, taking anywhere from 50 to 100 million years to complete one circuit. In the novels no one knows who created the airspheres or why, but it is presumed that whoever did has long since sublimed but may maintain some obscure link with the behemothaurs and lenticular entities. Guests in the airspheres are not allowed to use any force-field technology, though no reason has been offered for this prohibition. The airspheres resemble in some respects the orbit-sized ring of breathable atmosphere created by Larry Niven in The Integral Trees, but spherical not toroidal, require a force field to retain their integrity, and arose by artificial rather than natural processes.
== Health benefits == In the absence of liver disease, high levels of total bilirubin confers various health benefits. Studies have also revealed that levels of serum bilirubin (SBR) are inversely related to risk of certain heart diseases. While the poor solubility and potential toxicity of bilirubin limit its potential medicinal applications, current research is being done on whether bilirubin encapsulated silk fibrin nanoparticles can alleviate symptoms of disorders such as acute pancreatitis. In addition to this, there have been recent discoveries linking bilirubin and its ε-polylysine-bilirubin conjugate (PLL-BR), to more efficient insulin medication. It seems that bilirubin exhibits protective properties during the islet transplantation process when drugs are delivered throughout the bloodstream.
N-Desethylisotonitazene (norisotonitazene) is a benzimidazole opioid with potent analgesic effects which has been sold as a designer drug. It was first identified in 2023 as an active metabolite of the closely related compound isotonitazene, and was found to have similar potency. It is one of the strongest benzimidazole opioids discovered, with an analgesic strength 20 times stronger than fentanyl. Starting in 2023, it has become an increasingly widespread drug of abuse in its own right, linked to numerous overdose cases, and may be considered an analog of the schedule 1 drug metonitazene. In October 2023, the DEA published an intent to temporarily schedule etonitazepipne and N-desethylisotonitazene. As of April 2024, it is not yet controlled in the United States.
=== Pharmacodynamics === DPIA is a norepinephrine transporter inhibitor with an IC₅₀ value of 3.1 µM, as well as a dopamine transporter inhibitor with a potency approximately 13 times weaker than that of amphetamine, but 7 times more potent than amphetamine in inhibiting the serotonin transporter, although, unlike amphetamine, DPIA does not exhibit monoamine-releasing activity. It exhibits moderate affinity for 5-HT1A serotonin receptors (Ki = 3.5 µM) and for alpha-1A-adrenoreceptors (Ki = 0.12 µM), and binds to alpha-2A-adrenoreceptors and TAAR1. In experiments on rodents, DPIA produced the same central effects and toxicity as amphetamine, but was less potent. Interestingly, unlike amphetamine, DPIA caused a reduction in heart rate and blood pressure (exhibiting cardiodepressant properties).
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。
Cold storage slows the chemical degradation reactions that occur in solution. Lyophilized powder is more stable than reconstituted liquid and tolerates longer storage periods. Repeated temperature cycling should still be avoided because it can drive aggregation and loss of material.