reconstitution 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.
Last reviewed on 2026-04-04. 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.
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 |
|---|---|---|
| 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 |
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。
在信号层面，Tα1可能通过Toll样受体等模式识别受体发挥作用。部分实验显示，它能激活髓样分化因子88依赖的通路，进而促进核因子κB进入细胞核。这导致白细胞介素2、干扰素γ和白细胞介素12等细胞因子的转录增加。这些细胞因子偏向辅助性T细胞1型应答，有助于细胞免疫。然而，具体受体和结合位点尚未完全确定，不同实验模型的结果存在差异。
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。
Biologically, the peptide is studied mainly in the context of immune cell development and regulation. It is produced in the thymus and in several other tissues, and it appears to influence the maturation and activity of T cells and other immune populations. Laboratory work describes effects on cytokine production, on the balance between T cell subsets, and on the function of dendritic cells. Much of this evidence comes from cell culture and animal models, so the extent to which the same pathways operate in humans remains an open question.
Clinical interest has centered on chronic viral hepatitis, on immune restoration in various conditions, and on use as an adjuvant intended to improve responses to vaccines. Trials have reported mixed results, and regulatory status differs sharply between countries; in some places it is a prescription product, while elsewhere it is sold without an approved therapeutic indication. Because published studies vary widely in design, population, and endpoints, comparisons across them are difficult and no single conclusion covers the whole literature.
Thymosin alpha 1 is a short peptide of 28 amino acid residues that derives from the amino terminal region of a larger precursor protein known as prothymosin alpha. The peptide carries an acetyl group on its first residue and contains no disulfide bonds or carbohydrate chains. Its sequence is highly conserved across mammalian species, which is one reason laboratories treat it as a molecule with a defined and reproducible structure rather than a variable tissue extract. The name follows an early naming convention for thymus-derived fractions and does not imply that the peptide acts as a hormone in the classical endocrine sense.
The National Safety Council calculated that the lifetime odds of dying from an opioid overdose (1 in 96) in 2017 were greater than the lifetime odds of dying in an automobile accident (1 in 103) in the United States. The opioid epidemic, combined with the Patient Protection and Affordable Care Act, has led to a situation called the Florida shuffle, where a drug user moves between drug rehabilitation centers so those centers may bill the user's insurance company. In one study, a decision analytical model of the US population aged 12 years or older found that "under the status quo, an estimated 484,429 individuals were projected to die of fatal opioid overdose" between 2020 and 2029. However, a combination of "reducing opioid prescribing, increasing naloxone distribution, and expanding treatment for opioid use disorder was associated with an estimated 179,151 lives saved when compared to the status quo." Healthcare professionals are also among those heavily affected by this epidemic. Studies have been done to determine how well nursing students, nurses, and even doctors are prepared to treat patients affected by opioid addictions. The studies have pointed to the fact that nurses and other healthcare professionals are highly undertrained in this area. As a result, many specific education programs have been proposed and implemented into nursing education institutions.
Researchers at universities or other institutions outside of the NIH can apply for research project grants (RPGs) from the NIH. There are numerous funding mechanisms for different project types (e.g., basic research, clinical research, etc.) and career stages (e.g., early career, postdoc fellowships, etc.). The NIH regularly issues "requests for applications" (RFAs), e.g., on specific programmatic priorities or timely medical problems (such as Zika virus research in early 2016). In addition, researchers can apply for "investigator-initiated grants" whose subject is determined by the scientist. The total number of applicants has increased substantially, from about 60,000 investigators who had applied during the period from 1999 to 2003 to slightly less than 90,000 in who had applied during the period from 2011 to 2015. Due to this, the "cumulative investigator rate", that is, the likelihood that unique investigators are funded over a 5-year window, has declined from 43% to 31%. R01 grants are the most common funding mechanism and include investigator-initiated projects. The roughly 27,000 to 29,000 R01 applications had a funding success of 17-19% during 2012 though 2014. Similarly, the 13,000 to 14,000 R21 applications had a funding success of 13-14% during the same period. In FY 2016, the total number of grant applications received by the NIH was 54,220, with approximately 19% being awarded funding. Institutes have varying funding rates.
Metabolism (, from Greek μεταβολή (metabolē) 'change') refers to the set of life-sustaining chemical reactions that occur within living organisms. The three main functions of metabolism are the conversion of energy in food into a usable form for cellular processes; the conversion of food to building blocks of macromolecules (biopolymers) such as proteins, lipids, nucleic acids, and some carbohydrates; and the excretion of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow, reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells. In a broader sense, the set of reactions occurring within the cells is called intermediary (or intermediate) metabolism. Metabolic reactions may be categorized as catabolic—the breaking down of compounds (for example, of glucose to pyruvate by cellular respiration); or anabolic—the building up (biosynthesis) of compounds (such as proteins, carbohydrates, lipids, and nucleic acids). Usually, catabolism releases energy, and anabolism consumes energy. The chemical reactions of metabolism are organized into metabolic pathways, in which one chemical is transformed through a series of steps into another chemical, each step being facilitated by a specific enzyme.
Barbiturates are a class of depressant drugs that are chemically derived from barbituric acid. They are effective when used medically as anxiolytics, hypnotics, and anticonvulsants, but have physical and psychological addiction potential as well as overdose potential among other possible adverse effects. They have been used recreationally for their anti-anxiety and sedative effects, and are thus controlled in most countries due to the risks associated with such use. Barbiturates have largely been replaced by benzodiazepines and nonbenzodiazepines ("Z-drugs") in routine medical practice, particularly in the treatment of anxiety disorders and insomnia, because of the significantly lower risk of overdose, and the lack of an antidote for barbiturate overdose. Despite this, barbiturates are still in use for various purposes: in general anesthesia, epilepsy, treatment of acute migraines or cluster headaches, acute tension headaches, euthanasia, capital punishment, and assisted suicide.
Sources: en.wikipedia.org
== Inventions == James Watt did not invent the steam engine, nor were his ideas on steam engine power inspired by a kettle lid pressured open by steam. Watt improved upon the already commercially successful Newcomen atmospheric engine (invented in 1712 by Thomas Newcomen) in the 1760s and 1770s, making certain improvements critical to its future usage; his new steam engine later gained huge fame as a result. Although the guillotine was named after the French physician Joseph-Ignace Guillotin, he neither invented nor was executed with this device. He died peacefully in his own bed in 1814. Rather, it was Guillotin's speech favoring beheadings over other forms of execution that led to the device being referred to as "La machine Guillotine" and later simply guillotine. Thomas Crapper did not invent the flush toilet. A forerunner of the modern toilet was invented by the Elizabethan courtier Sir John Harington in the 16th century, and in 1775 the Scottish mechanic Alexander Cumming developed and patented a design for a toilet with an S-trap and flushing mechanism. Crapper, however, did much to increase the popularity of the flush toilet and introduced several innovations in the late 19th century, holding nine patents, including one for the floating ballcock. Thomas Edison did not invent the light bulb.
=== Disease === The normal bone marrow architecture can be damaged or displaced by aplastic anemia, malignancies such as multiple myeloma, or infections such as tuberculosis, leading to a decrease in the production of blood cells and blood platelets. The bone marrow can also be affected by various forms of leukemia, which attacks its hematologic progenitor cells. Furthermore, exposure to radiation or chemotherapy will kill many of the rapidly dividing cells of the bone marrow, and will therefore result in a depressed immune system. Many of the symptoms of radiation poisoning are due to damage sustained by the bone marrow cells. To diagnose diseases involving the bone marrow, a bone marrow aspiration is sometimes performed. This typically involves using a hollow needle to acquire a sample of red bone marrow from the crest of the ilium under general or local anesthesia.
== History == The discovery of coordination polymers, or as later termed metal-organic frameworks, was a logical continuation of research on post-zeolite materials. In 1989 Richard Robson reported the first organic copper-based coordination network by complexation of anions with tetrahedral bridging ligands. Similar copper(I) coordination polymers have been synthesized in 1992 by Susumu Kitagawa, which contained pores with loosely bound acetone molecules, but the structure would collapse upon their removal. Further efforts were devoted to develop extended 3D porous networks that would be stable upon removal of guest molecule and would exhibit permanent porosity. In 1995, Omar M. Yaghi demonstrated interpenetrated 2-D structure with carboxylate-based linkers that remained stable upon guest removal and could re-adsorb specific aromatic molecules. Permanent porosity in 3-D coordination polymer was first demonstrated in 1997 by Susumu Kitagawa. A year later, Yaghi proposed a new synthetical concept that employs secondary building units (SBUs) — metal-carboxylate clusters that serve as rigid building blocks for constructing frameworks with permanent porosity. In 1999, Yaghi and colleagues used SBU approach to synthesize MOF-5 that consists of zinc oxide clusters and terephthalate linkers. MOF-5 exhibits strong bonds between metal centers and coordinating organic molecules and hence exhibits high thermal stability while maintaining high porosity..
Sources: en.wikipedia.org
=== Biosimilar drugs === Biosimilar drugs are biological products that are highly similar to an already approved biologic drug, with few or no clinically meaningful differences in terms of safety, purity, and potency. These drugs are developed to be equivalent to the reference biologic, often at a lower cost, providing alternative treatment options. In the context of ankylosing spondylitis, biosimilars are typically used as alternatives to the original biologic drugs. Biosimilars for ankylosing spondylitis may include versions of tumor necrosis factor inhibitors or other biologics commonly used in the treatment of the condition. When possible, physicians are recommended to use the original drugs over the biosimilar versions. Even biosimilars with perfect replication of the quality, composition, and other properties of the original drug are susceptible to nocebo effects.
Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) Psilocin (4-hydroxy-N,N-dimethyltryptamine) Baeocystin (4-phosphoryloxy-N-methyltryptamine) Norbaeocystin (4-phosphoryloxytryptamine) Aeruginascin (N,N,N-trimethyl-4-phosphoryloxytryptamine) The potential psychoactivity of other compounds other than psilocybin and psilocin has been speculated but not confirmed. The concentrations of psilocin and psilocybin, as determined by high-performance liquid chromatography, are in the range of 0.14–0.42% (wet weight) and 0.37–1.30% (dry weight) in the whole mushroom 0.17–0.78% (wet weight) and 0.44–1.35% (dry weight) in the cap, and 0.09%–0.30% (wet weight) and 0.05–1.27% (dry weight) in the stem, respectively. For quickly and practically measuring the psychoactive contents of most healthy Psilocybe cubensis varieties, it can generally be assumed that there is approximately 15 mg (± 5 mg) of psilocybin per gram of dried mushroom. Furthermore, due to factors such as age and storage method, the psilocybin and psilocin content of a given sample of mushrooms will vary. Individual body composition, brain chemistry and psychological predisposition play a significant role in determining appropriate doses. For a modest psychedelic effect, a minimum of one gram of dried Psilocybe cubensis mushrooms is ingested orally, 0.25–1 gram is usually sufficient to produce a mild effect, 1–2.5 grams usually provides a moderate effect and 2.5 grams and higher usually produces strong effects.
==== Employees and DuPont exposed community ==== In 2010, the three members of the C8 Science Panel published a review of the epidemiological evidence on PFOA exposure in Environmental Health Perspectives. Insufficient evidence exists to conclude PFOA causes adverse health effects in humans, but consistent evidence exists on associations with higher cholesterol and uric acid. Whether or not these potential effects result in an increase in cardiovascular disease is unknown. Further data on the 69,030 member cohort that is being studied by the panel is scheduled for release through 2012. A 2011 epidemiological study demonstrated "probable link" between PFOA and kidney cancer, testicular cancer, thyroid disease, high cholesterol, pre-eclampsia and ulcerative colitis. Facial birth defects, an effect observed in rat offspring, occurred with the children of two out of seven female DuPont employees from the Washington Works facility from 1979 to 1981. Bucky Bailey is one of the affected individuals; DuPont, however, does not accept any liability from the toxicity of PFOA. While 3M sent DuPont results from a study that showed birth defects to rats administered PFOA and DuPont moved the women out of the Teflon production unit, subsequent animal testing led DuPont to conclude there was no reproductive risk to women, and they were returned to the production unit. However, data released in March 2009 on the community around DuPont's Washington Works plant showed "a modest, imprecise indication of an elevation in risk ... above the 90th percentile ...
During his 2022 gubernatorial campaign, Moore said he supported the Inclusive Schools Act, a bill introduced in the 2022 legislative session that banned schools from discriminating against students based on their sexual orientation and gender identity. He also supported the Trans Health Equity Act, a bill that would have required the state's Medicaid program to cover gender-affirming treatments. In December 2022, Moore praised the signing of the Respect for Marriage Act, which codifies same-sex and interracial marriage rights. On March 31, 2023, Moore became the first Maryland governor to recognize International Transgender Day of Visibility when he issued an official proclamation. In May 2023, Moore signed the Trans Health Equity Act into law and allowed a bill furthering an earlier repeal of the state's sodomy law to become law without his signature. In June 2023, he signed an executive order to protect people or entities that provide gender-affirming care from legal punishments by other states. During the 2024 legislative session, Moore signed into law the Trans Shield Act, which prevents states with anti-trans laws from prosecuting patients or entities within Maryland for providing gender-affirming care. In May 2025, Moore signed into law a bill decriminalizing the spread of HIV.
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.
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。