Thymosin fraction 5 is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-08-01. Numbers and descriptions here follow the published literature rather than marketing material.
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。
Thymosin beta-4 is a separate 43-residue peptide that binds actin and participates in cell migration; it shares no sequence similarity with thymosin alpha-1 despite the common family name. Other preparative materials, such as thymosin fraction 5 and thymopoietin, contain distinct mixtures or peptides. The shared thymosin label reflects the tissue of origin used in early purification, not a common structural core. Treating these molecules as interchangeable is a frequent source of confusion in laboratory reports and in popular summaries alike.
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.
| Property | Value | Notes |
|---|---|---|
| 主要靶细胞 | T细胞、树突状细胞 | 也影响NK细胞 |
| 信号通路 | TLR/MyD88/NF-κB | 部分实验模型 |
| 细胞因子偏向 | Th1型 | 增加IL-2、IFN-γ |
| 给药途径 | 皮下注射 | 临床常用 |
| 半衰期 | 约2小时 | 血浆中较短 |
The first arc of the series, Trails in the Sky, consists of three games. They are set within the Liberl Kingdom and primarily follow Estelle Bright and her adopted brother Joshua, members of the Bracer's Guild, a civilian peacekeeping and monster-hunting organization. The first game, Trails in the Sky, was released in Japan in 2004 for Windows and for the PlayStation Portable (PSP) in 2006. The second game, Trails in the Sky SC, continues the plot of the first and was released in Japan for Windows in 2006 and the PSP the following year. The third game, Trails in the Sky the 3rd, follows Septian Church agent Kevin Graham, who is sent to an otherworldly dimension known as Phantasma alongside many characters from the previous two games. Sky the 3rd also features vignettes exploring character backstories as well as foreshadowing plot elements explored in later arcs. It was released in Japan in 2007 for Windows and the PSP in 2008. A 3D remake of the first game, Trails in the Sky 1st Chapter, released worldwide for Nintendo Switch, Nintendo Switch 2, PlayStation 5, and Windows in 2025. A remake of the sequel, Trails in the Sky 2nd Chapter, has been released for the same platforms in 2026. In 2010, Xseed Games acquired the rights to localize and publish the trilogy in English.
That the notochord evolved de novo in chordates by combining development programs in new ways. That the notochord derives from a homologous muscular structure, the axochord, that was present in annelid-like ancestors of the chordates. Supported by gene expression patterns and identification of said muscular structures in various inveterates, but cannot fully rule out the possibility of homoplasy. Deciding between these two scenarios (or possibly another yet to be proposed) should be facilitated by much more thorough studies of gene regulatory networks in a wide spectrum of animals.
== Definition == Vitamin B12 is a coordination complex of cobalt, which occupies the center of a corrin ligand and is further bound to a benzimidazole ligand and adenosyl group. Several related species behave similarly to function as vitamins. This collection of compounds is sometimes referred to as "cobalamins". These chemical compounds have a similar molecular structure, each of which shows vitamin activity in a vitamin-deficient biological system. They are referred to as vitamers having vitamin activity as a coenzyme, meaning that its presence is required for some enzyme-catalyzed reactions.
=== Brown adipose tissue === Brown adipose tissue stores free fatty acids rather than triglycerides, and is especially abundant in newborn and hibernating mammals. Brown adipose tissue is involved in thermogenesis, and has a considerably higher glyceroneogenesis activity. Brown adipose tissue contains more glyceroneogenesis-related enzymes, in particular PEPC-K and glycerol kinase. PEPC-K is around 10 times more active than in white adipose tissue, and is the key regulatory enzyme that controls the activity of the pathway. Glycerol kinase phosphorylates glycerol to generate glycerol 3-phosphate, which is used to build triglycerides. An increase in the activity of glycerol kinase will increase the production of glycerol 3-phosphate. Glyceroneogenesis in brown adipose tissue contributes to thermogenesis, a process that generates heat in warm-blooded animals by delivering free fatty acids to the mitochondria. In normal conditions, thermogenesis is down-regulated by the low concentration of free fatty acids in the cytosol, because glyceroneogenesis re-esterifies fatty acids to triglycerides. When exposed to cold, a neurotransmitter hormone called norepinephrine suppresses the activity of PEPC-K and thus the glyceroneogenesis re-esterification, increasing the availability of free fatty acids within the cell. Excess free fatty acids in the cytosol will consequently be delivered to the mitochondria for thermogenesis.
A supercentenarian, sometimes hyphenated as super-centenarian, is a person who has reached the age of 110 years. This age milestone is only achieved by about one in a thousand centenarians. Even rarer is a person who has lived to 115. There are 82 people in recorded history who have indisputably reached 115. Only three of the people who have reached 115 are men. Ethel Caterham, Naomi Whitehead, Lucia Laura Sangenito, Yolanda Beltrão de Azevedo, and Beatriz Ferreira Duarte are the only people currently alive who have verifiably reached the 115 year milestone. Jeanne Calment from France is the only age-verified person in human history to have reached the age of 120 years.
Sources: en.wikipedia.org
However, in polluted urban areas, lichen bodies often die before reaching these later developmental stages. Morphological effects of pollution include smaller thalli, fewer and smaller apothecia, and weaker substrate attachment at later developmental stages. Rather than accelerating development under stress, as some plant species do, X. parietina exhibits retarded development of pregenerative individuals and elimination of less tolerant generative individuals. Its pollution tolerance also varies with light availability; optimal conditions appear to be in areas with low pollution and good illumination, where young generative individuals dominate and reproductive capacity is highest. The species also demonstrates high metal tolerance. A key mechanism is the immobilization of toxic metals in the apoplast (the extracellular space between the cell wall and plasma membrane), preventing them from entering living cells. Additionally, it produces protective thiol peptides, increases antioxidant production, and maintains membrane integrity under metal stress. Laboratory studies indicate differential sensitivity to various metals, with its tolerance being higher for cadmium and nickel but lower for copper and mercury. It also shows resilience to pesticide exposure, persisting in untreated gardens but declining in semi-intensive orchards and disappearing in intensively sprayed orchards. These physiological responses to various pollutants make this species valuable for environmental monitoring applications.
== Interactions == Concomitant or recent (previous 14 days) monoamine oxidase inhibitor (MAOI) use can lead to hypertensive reactions, including hypertensive crisis, and should be avoided. Clinical studies have found minimal or no influence of certain MAOIs like the weak non-selective MAOI linezolid and the potent selective MAO-B inhibitor selegiline (as a transdermal patch) on the pharmacokinetics of pseudoephedrine. This is in accordance with the fact that pseudoephedrine is not metabolized by monoamine oxidase (MAO). However, pseudoephedrine induces the release of norepinephrine, which MAOIs inhibit the metabolism of, and as such, MAOIs can still potentiate the effects of pseudoephedrine. No significant pharmacodynamic interactions have been found with selegiline, but linezolid potentiated blood pressure increases with pseudoephedrine. However, this was deemed to be without clinical significance in the case of linezolid, though it was noted that some individuals may be more sensitive to the sympathomimetic effects of pseudoephedrine and related agents. Pseudoephedrine is contraindicated with MAOIs like phenelzine, tranylcypromine, isocarboxazid, and moclobemide due to the potential for synergistic sympathomimetic effects and hypertensive crisis. It is also considered to be contraindicated with linezolid and selegiline as some individuals may react more sensitively to coadministration.
What we have got is the smoking gun - the thing that caused his illness and was given to him with malice." Subsequently, French and Russian teams claimed that the elevated 210Po levels were not the result of deliberate poisoning, and did not cause Arafat's death. It has also been suspected that Russian businessman Roman Tsepov was killed with polonium. He had symptoms similar to Litvinenko's.
== Product == The extract is available commercially as Calocurb, an oral dietary supplement for appetite management which was launched in New Zealand in 2018. The capsule has an enteric coating to pass through the stomach and allow delivery to the small intestine.
=== Legacy === Hahn is considered the father of radiochemistry and nuclear chemistry. He is chiefly remembered for the discovery of nuclear fission, the basis of nuclear power and nuclear weapons. Glenn Seaborg wrote that "it has been given to very few men to make contributions to science and to humanity of the magnitude of those made by Otto Hahn". His award of the 1944 Nobel Prize for Chemistry was in recognition for this discovery. However later commentators have argued that Lise Meitner's exclusion reflected sexism and antisemitism within the Nobel Committee. Conflict between chemists and physicists and the theorists and experimentalists also played a role. Hahn's efforts to rehabilitate the image of Germany after the war have also been viewed as problematic. Hahn has been described as politically passive during the Nazi era, suggesting that while he was not a party member, he tolerated colleagues who were and thus shared moral complicity. In a letter to James Franck dated 22 February 1946, Meitner wrote:Hahn is without doubt a decent man with many good traits. He only lacks thoughtfulness and perhaps also a certain strength of character, things that in normal times are minor flaws, but in the complicated times of today have deeper implications.
Sources: en.wikipedia.org
== Medical uses == Hyaluronic acid has been FDA-approved to treat osteoarthritis of the knee via intra-articular injection. A 2012 review showed that the quality of studies supporting this use was mostly poor, with a general absence of significant benefits, and that intra-articular injection of HA could possibly cause adverse effects. A 2020 meta-analysis found that intra-articular injection of high molecular weight HA improved both pain and function in people with knee osteoarthritis. Hyaluronic acid has been used to treat dry eye. Hyaluronic acid is a common ingredient in skin care products. Hyaluronic acid is used as a dermal filler in cosmetic surgery. It is typically injected using either a classic sharp hypodermic needle or a micro-cannula. Hyaluronic acid may be used as a soft tissue filler, including to separate tissues exposed to radiation for prostate cancer. Complications may involve injury to nerves and microvessels, pain, and bruising, with possible side effects including erythema, itching, and vascular occlusion. In some cases, hyaluronic acid fillers can result in a granulomatous foreign body reaction.
Inadequate nutritional intake: Alcoholics tend to take in less than the recommended amount of thiamine. Decreased uptake of thiamine from the GI tract: Active transport of thiamine into enterocytes is disturbed during acute alcohol exposure. Liver thiamine stores are reduced due to hepatic steatosis or fibrosis. Impaired thiamine utilization: Magnesium, which is required for the binding of thiamine to thiamine-using enzymes within the cell, is also deficient due to chronic alcohol consumption. The inefficient use of any thiamine that does reach the cells will further exacerbate the thiamine deficiency. Ethanol per se inhibits thiamine transport in the gastrointestinal system and blocks phosphorylation of thiamine to its cofactor form (ThDP). Following improved nutrition and the removal of alcohol consumption, some impairments linked with thiamine deficiency are reversed, in particular poor brain functionality, although in more severe cases, Wernicke–Korsakoff syndrome leaves permanent damage. (See delirium tremens.)
Sioux Nation of Indians and was involved in the Black Hills Land Claim John Lowenthal (1947), lawyer and documentary filmmaker known for his defense of Alger Hiss Norman Dorsen (1950), professor at the New York University School of Law and former president of the American Civil Liberties Union Robert O. Harris (1951), labor lawyer and chairman of the National Mediation Board Norman Marcus (1953), New York City Planning Commission general counsel and zoning expert Richard H. Stern (1953), attorney and law professor David Braun (1954), music industry lawyer, former president of PolyGram Records Alvin Hellerstein (1954), US federal judge Isaac Shapiro (1954), head of international practice at Skadden, Arps, Slate, Meagher & Flom, former president of Japan Society Clarence Benjamin Jones (1956), attorney and advisor to Martin Luther King Jr. Jerome H. Kern (1957), founder of Wachtell, Lipton, Rosen & Katz, former CEO of Playboy and Colorado Symphony Bernard Nussbaum (1958), White House counsel under Bill Clinton Ezra G. Levin (1959), lawyer, co-chair of international law firm Kramer Levin Naftalis & Frankel David G. Trager (1959), judge on the United States District Court for the Eastern District of New York Robert Abrams (1960), Bronx borough president and New York state attorney general Frank Tuerkheimer (1960), Watergate prosecutor and former U.S. attorney for the Western District of Wisconsin José A. Cabranes (1961), judge of the U.S. Court of Appeals; first Puerto Rican to sit in a U.S. District Court; current trustee of Columbia University Michael B.
== Pathophysiology == Chronic wounds may affect only the epidermis and dermis, or they may affect tissues all the way to the fascia. They may be formed originally by the same things that cause acute ones, such as surgery or accidental trauma, or they may form as the result of systemic infection, vascular, immune, or nerve insufficiency, or comorbidities such as neoplasias or metabolic disorders. The reason a wound becomes chronic is that the body's ability to deal with the damage is overwhelmed by factors such as repeated trauma, continued pressure, ischemia, or illness. Though much progress has been accomplished in the study of chronic wounds lately, advances in the study of their healing have lagged behind expectations. This is partly because animal studies are difficult because animals do not get chronic wounds, since they usually have loose skin that quickly contracts, and they normally do not get old enough or have contributing diseases such as neuropathy or chronic debilitating illnesses. Nonetheless, current researchers now understand some of the major factors that lead to chronic wounds, among which are ischemia, reperfusion injury, and bacterial colonization.
Sources: en.wikipedia.org
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。
It is a 28-residue synthetic peptide studied as an immune-modulating agent and approved as a drug in some countries. The sequence matches a naturally occurring fragment isolated from thymus tissue. It is not a hormone in the endocrine sense.