thymalfasin raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-05-06. Anything still debated is marked as such rather than presented as settled.
Thymosin alpha-1 is a synthetic 28-amino-acid peptide whose sequence was first identified in extracts of bovine thymus tissue during the 1970s. The chain carries an acetyl group on its N-terminal serine. Its acidic residue content is high, which produces strong water solubility and an isoelectric point well below neutrality. Material supplied for laboratory and clinical use is manufactured by solid-phase peptide synthesis rather than purified from animal tissue. Different salt forms, such as the acetate, alter the counter-ion content without changing the peptide backbone.
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.
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。
| Property | Value | Notes |
|---|---|---|
| Amino acid length | 28 residues | Single chain with an acetylated N-terminus |
| Molecular mass | Approximately 3,108 Da | Small shifts occur with counter-ion and water content |
| Isoelectric point | Around 3.5 | Low value follows from the many acidic residues |
| Parent molecule | N-terminal region of prothymosin alpha | Free circulating form in humans is not firmly established |
| Common synonyms | Thymalfasin; T alpha 1 | Older literature also uses the full spelled-out form |
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.
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.
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.
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.
Bobby Flay's Bold American Food (Warner Books, May 31, 1994) – ISBN 978-0-4465-1724-9 Bobby Flay's From My Kitchen to Your Table (Clarkson Potter, March 31, 1998) – ISBN 978-0-517-70729-6 Bobby Flay's Boy Meets Grill (Hyperion, May 19, 1999) – ISBN 978-0-7868-6490-4 Bobby Flay Cooks American (Hyperion, September 30, 2001) – ISBN 978-0-7868-6714-1 Bobby Flay's Boy Gets Grill (Scribner, May 18, 2004) – ISBN 978-0-7432-5481-6 Bobby Flay's Grilling For Life (Scribner, May 3, 2005) – ISBN 978-0-7432-7272-8 Bobby Flay's Mesa Grill Cookbook (Clarkson Potter, October 16, 2007) – ISBN 978-0-3073-5141-8 Bobby Flay's Grill It! (Clarkson Potter, April 18, 2008) – ISBN 978-0-3073-5142-5 Bobby Flay's Burgers, Fries and Shakes (Clarkson Potter, April 11, 2009) – ISBN 978-0-3074-6063-9 Bobby Flay's Bar Americain Cookbook: Celebrate America's Great Flavors (Clarkson Potter, September 20, 2011) – ISBN 978-0-307-46138-4 Bobby Flay's Throwdown (Clarkson Potter, October 12, 2012) – ISBN 978-0-3077-1916-4 Bobby Flay's Barbecue Addiction (Clarkson Potter, April 23, 2013) – ISBN 978-0-3074-6139-1 Bobby Flay Fit: 200 Recipes for a Healthy Lifestyle (Co-authors: Stephanie Banyas and Sally Jackson; Publisher – Clarkson Potter, December 5, 2017) - ISBN 978-0-3853-4593-4 Bobby at Home: Fearless Flavors from My Kitchen (Clarkson Potter, September 24, 2019) – ISBN 978-0-3853-4591-0
In 2009, Lilly pleaded guilty for illegally marketing antipsychotic medication Zyprexa and agreed to pay a $1.415 billion penalty that included a criminal fine of $515 million, the largest ever in a healthcare case and the largest criminal fine for an individual corporation ever imposed in a US criminal prosecution of any kind at the time. Eli Lilly has faced many lawsuits from people who claimed they developed diabetes or other diseases after taking olanzapine (branded Zyprexa), an antipsychotic medication, as well as by various governmental entities, insurance companies, and others. Internal documents provided to The New York Times revealed that Lilly had downplayed the risks of Zyprexa. According to the documents, 16 percent of people taking Zyprexa gained more than 66 pounds in their first year, a much larger figure than Eli Lilly had shared with doctors. In 2006, Lilly paid $700 million to settle around 8,000 of these lawsuits, and in early 2007, Lilly settled around 18,000 suits for $500 million, which brought the total Lilly had paid to settle suits related to the drug to $1.2 billion. In March 2008, Lilly settled a suit with the state of Alaska, and in October 2008, Lilly agreed to pay $62 million to 32 states and the District of Columbia to settle suits brought under state consumer protection laws. In 2009, four sales representatives for Eli Lilly filed separate qui tam lawsuits against the company for illegally marketing Zyprexa for uses not approved by the Food and Drug Administration.
Norepinephrine has been reported to exist in a wide variety of animal species, including protozoa, placozoa and cnidaria (jellyfish and related species), but not in ctenophores (comb jellies), whose nervous systems differ greatly from those of other animals. It is generally present in deuterostomes (vertebrates, etc.), but in protostomes (arthropods, molluscs, flatworms, nematodes, annelids, etc.) it is replaced by octopamine, a closely related chemical with a closely related synthesis pathway. In insects, octopamine has alerting and activating functions that correspond (at least roughly) with the functions of norepinephrine in vertebrates. It has been argued that octopamine evolved to replace norepinephrine rather than vice versa; however, the nervous system of amphioxus (a primitive chordate) has been reported to contain octopamine but not norepinephrine, which presents difficulties for that hypothesis.
The Inter-American Commission on Human Rights called "upon the United States to: refrain from employing lethal military force in the context of public security operations, ensuring that any counter-crime or security operation fully complies with international human rights standards; conduct prompt, impartial, and independent investigations into all deaths and detentions resulting from these actions; and adopt effective measures to prevent recurrence" and urged the US to "to ensure that all security operations, including those carried out beyond its borders, are consistent with international human rights obligations, particularly regarding the protection of the right to life, the use of force, due process guarantees, and accountability mechanisms."
Sources: en.wikipedia.org
Severe respiratory instability Acute psychiatric instability Uncontrolled suicide risk Diagnosed non-nicotine substance abuse QTc intervals longer than 500 milliseconds if prescribed methadone Acute diversion of controlled substances Intolerance from previous trial use with specific opioids Serious adverse effects or lack of efficacy
=== Mechanism of action === As an adenosine nucleoside triphosphate analog (GS-443902), the active metabolite of remdesivir interferes with the action of viral RNA-dependent RNA polymerase and evades proofreading by viral exoribonuclease (ExoN), causing a decrease in viral RNA production. In some viruses, such as the respiratory syncytial virus, it causes the RNA-dependent RNA polymerases to pause, but its predominant effect (as in Ebola) is to induce an irreversible chain termination. Unlike with many other chain terminators, this is not mediated by preventing addition of the immediately subsequent nucleotide, but is instead delayed, occurring after five additional bases have been added to the growing RNA chain. For the RNA-dependent RNA polymerases of MERS-CoV, SARS-CoV-1, and SARS-CoV-2, arrest of RNA synthesis occurs after incorporation of three additional nucleotides. Hence, remdesivir is classified as a direct-acting antiviral agent that works as a delayed chain terminator.
== Synaptic plasticity == AMPA receptors (AMPAR) are both glutamate receptors and cation channels that are integral to plasticity and synaptic transmission at many postsynaptic membranes. One of the most widely and thoroughly investigated forms of plasticity in the nervous system is known as long-term potentiation (LTP). There are two necessary components of LTP: presynaptic glutamate release and postsynaptic depolarization. Therefore, LTP can be induced experimentally in a paired electrophysiological recording when a presynaptic cell is stimulated to release glutamate on a postsynaptic cell that is depolarized. The typical LTP induction protocol involves a "tetanus" stimulation, which is a 100-Hz stimulation for 1 second. When one applies this protocol to a pair of cells, one will see a sustained increase of the amplitude of the excitatory postsynaptic potential (EPSP) following tetanus. This response is interesting because it is thought to be the physiological correlation for learning and memory in the cell. In fact, it has been shown that, following a single paired-avoidance paradigm in mice, LTP can be recorded in some hippocampal synapses in vivo. The molecular basis for LTP has been extensively studied, and AMPARs have been shown to play an integral role in the process. Both GluR1 and GluR2 play an important role in synaptic plasticity.
The state prosecuted the accused as Marxist revolutionaries seeking to establish a Soviet-backed regime in South West Africa. In what became known as the "1967 Terrorist Trial", six of the accused were found guilty of committing violence in the act of insurrection, with the remainder convicted for armed intimidation, or having received military training for the purpose of insurrection. During the trial, the defendants unsuccessfully argued against allegations that they were privy to an external communist plot. All but three received sentences ranging from five years to life imprisonment on Robben Island.
Secondhand smoke is tobacco smoke which affects people other than the 'active' smoker. It is made up of the exhaled smoke (15%) and mostly of smoke coming from the burning end of the cigarette, known as sidestream smoke (85%). Secondhand smoke contains more than 7000 chemicals, of which hundreds are harmful to health. Secondhand tobacco smoke includes both a gaseous and a particulate materials which, with particular hazards arising from levels of carbon monoxide and small particulates (fine particulate matter, especially PM2.5 and PM10) which get into the bronchioles and alveoles in the lung. Inhaling secondhand smoke on multiple occasions can cause asthma, pneumonia, lung cancer, and sudden infant death syndrome, among other conditions. Thirdhand smoke (THS) refers to chemicals that settle on objects and bodies indoors after smoking. Exposure to thirdhand smoke can happen even after the actual cigarette smoke is not present anymore and affect those entering the indoor environment much later. Toxic substances of THS can react with other chemicals in the air and produce new toxic chemicals that are otherwise not present in cigarettes. The only certain method to improve indoor air quality as regards secondhand smoke is to eliminate smoking indoors. Indoor e-cigarette use also increases home particulate matter concentrations.
Sources: en.wikipedia.org
==== Hong Kong ==== The scandal led to an erosion of trust in locally produced infant formula and from then on, many Shenzhen residents and parallel traders travelled across the border to purchase powdered milk from Hong Kong shops. Lower confidence in mainland Chinese production, combined with the relaxation of visa requirements for mainland residents, had resulted in shortages of infant formula in Hong Kong for an extended time. Because of a great public outcry, the Import and Export (General) (Amendment) Regulation 2013 was passed in Hong Kong, prohibiting the unlicensed export of powdered formula, including milk and soya milk powder for infants and children under 36 months. According to the HK government, the regulation is not applicable to "powdered formula that is exported in the accompanied personal baggage of a person aged 16 or above leaving Hong Kong if the person did not leave Hong Kong in the last 24 hours and the formula does not exceed 1.8 kg [4 lb] in total net weight". Although the Hong Kong government imposed a strict 2-can limit on the export of infant formula in March 2013, spurred price differentials caused by sales tax on the mainland and lax customs, trafficking activity including for powdered milk has continued, exacerbating the Hong Kong-Mainland conflict. The catchment area for traffickers spread from Fan Ling and Sheung Shui southward to Yuen Long and Tuen Mun, causing localist camp such as Civic Passion and Hong Kong Indigenous to take to the streets in direct action in 2015.
=== 2007–2013 === Helton's power and RBI production stayed relatively level to his previous year's stats during the 2007 season, as he managed 17 home runs and 91 RBI. These numbers were well below his career norms, yet Helton kept up his string of seven consecutive seasons with an on-base percentage higher than .400, nine consecutive seasons with a batting average above .300, and also walked more times than he struck out (a feat he accomplished in seven of his first ten full seasons). Helton recorded his 1,000th career hit at Coors Field on June 20, in a 6–1 home win over the New York Yankees, becoming only the fifth active player to have 1,000 career hits in one ballpark. On September 9, in 4–2 home victory over the San Diego Padres, Helton hit his 35th double of the season. This made him the only player in MLB history to have hit 35 or more doubles in at least 10 consecutive seasons (1998–2007). Helton hit his 300th career home run on September 16 in a 13–0 home win over the Florida Marlins. He became the first player to hit 300 home runs for the Rockies. The 2007 season was a wild see-saw affair for the Rockies. After they began the season with a 13-1 record, threatening to run away with the division, they underwent multiple red hot and ice cold streaks, leaving them in a desperate spot in September, as they tried to earn a playoff spot for the first time since their brief October appearance of 1995.
== Censorship == During the conflict, the Taliban's intelligence agency, the General Directorate of Intelligence (GDI), ordered Afghan domestic media outlets not to cover areas targeted in recent Pakistani airstrikes. In some cases, intelligence personnel monitored media offices and newsroom operations to enforce the directive, and media outlets were warned against defying the order. Taliban intelligence officials also warned residents against publishing images or details of locations in Afghanistan targeted by Pakistani strikes. Afghan local sources stated that the Taliban were restricting access to information about their own casualties, as well as those among civilians. They added that only Taliban members were allowed to take images of affected areas and victims, making independent verification of casualties and damage difficult. According to the sources, even Taliban controlled media outlets were not allowed to photograph the sites and areas targeted by Pakistan's airstrikes, and there were no accurate statistics on the casualties of civilians and Taliban fighters. On 1 March, the Taliban suspended the broadcasts of Rah-e-Farda radio and television in Kabul, a channel affiliated with Mohammad Mohaqiq. The suspension was linked to remarks by Mohammad Mohaqiq, which reportedly criticized the Taliban's recent retaliatory attacks against Pakistan. On 5 March, the Taliban increased pressure on local media outlets, warning journalists not to report on attacks, particularly those targeting Taliban military sites.
== Signs and symptoms == Benign tumors are very diverse; they may be asymptomatic or may cause specific symptoms, depending on their anatomic location and tissue type. They grow outward, producing large, rounded masses which can cause what is known as a "mass effect". This growth can cause compression of local tissues or organs, leading to many effects, such as blockage of ducts, reduced blood flow (ischaemia), tissue death (necrosis) and nerve pain or damage. Some tumors also produce hormones that can lead to life-threatening situations. Insulinomas can produce large amounts of insulin, causing hypoglycemia. Pituitary adenomas can cause elevated levels of hormones such as growth hormone and insulin-like growth factor-1, which cause acromegaly; prolactin; ACTH and cortisol, which cause Cushing's disease; TSH, which causes hyperthyroidism; and FSH and LH. Bowel intussusception can occur with various benign colonic tumors. Cosmetic effects can be caused by tumors, especially those of the skin, possibly causing psychological or social discomfort for the person with the tumor. Vascular tissue tumors can bleed, in some cases leading to anemia.
Sources: en.wikipedia.org
It is usually described as an immunomodulatory peptide rather than a classic circulating hormone. No endocrine gland is known to release it as a primary secretory product, and its measured presence in blood is not firmly established.
Prothymosin alpha is a much larger acidic protein, roughly 111 to 113 residues long, and the thymosin alpha-1 sequence matches its N-terminal region. The small peptide is therefore best understood as a fragment of that parent protein rather than a separate gene product.
Trials and clinical reports have examined chronic hepatitis B and C, use as a vaccine adjuvant, and supportive treatment in some immunodeficiency and oncology settings. Results vary by indication, and regulatory approval differs between countries.
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。