The short version of clinical endpoint fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-18. Anything still debated is marked as such rather than presented as settled.
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.
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.
Early work on thymic extracts in the 1960s described a heat-stable acidic fraction containing many polypeptides. Separation of that mixture yielded individual components, and thymosin alpha-1 was named as one of them on the basis of assays for T-cell activity. The first preparations came from calf thymus, while subsequent research and clinical material has been chemically synthesized. Nomenclature in older papers is inconsistent, and the same peptide sometimes appears under different designations, which complicates literature searches.
| Property | Value | Notes |
|---|---|---|
| First described | 1977 | Reported as a component of thymosin fraction 5 |
| Sequence length | 28 amino acids | N-terminal residue is acetylated |
| Net charge at neutral pH | Negative | Reflects a high proportion of acidic residues |
| Principal studied uses | Chronic hepatitis B and vaccine adjuvant | Research uses outnumber approved indications |
| Regulatory status | Approved in a limited number of countries | Not approved in the United States or most of Europe |
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.
Lyophilized material is typically treated as a hygroscopic solid that should be brought to room temperature before the container is opened, which limits condensation on the powder. Reconstitution is commonly done with sterile water or a buffered diluent, and gentle mixing is preferred over vigorous agitation to reduce foaming and surface adsorption. Because peptides can bind to plastic and glass, diluents containing a small amount of carrier protein are sometimes used in laboratory work. Working solutions are generally aliquoted and prepared fresh rather than subjected to repeated freezing and thawing.
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.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids, corresponding to the N-terminal fragment of prothymosin alpha. Its sequence begins with acetylation at the N-terminus, a modification that affects stability and receptor interaction. The peptide is acidic, with a calculated isoelectric point near 4.2, and carries no disulfide bonds, so its secondary structure is largely flexible in solution. Molecular mass is approximately 3108 daltons. The native form was first isolated from bovine thymus tissue, while pharmaceutical material is produced by solid-phase peptide synthesis.
Within the immune system, the peptide acts on several cell types rather than a single target. Reported activities include promotion of T-cell maturation, enhancement of natural killer cell activity, and modulation of cytokine production by dendritic cells and macrophages. Some of these effects appear to operate through toll-like receptor signaling, though the precise receptor-level mechanism remains debated. Whether the observed immune changes translate into clinical benefit is a separate question and depends on the indication studied.
The peptide was described in the 1970s as a component of thymic extracts, and early research focused on restoring immune function in immunodeficiency states. A synthetic version entered clinical development in the 1980s and is approved as a drug in several countries for conditions such as chronic hepatitis B and certain immunodeficiencies. Approval status varies widely by jurisdiction, and in the United States it is not an approved therapeutic. Regulatory and clinical positions differ, so statements about efficacy should be tied to specific indications and studies.
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。
=== Democratic primary === Caitlin Rourk, Democratic Nominee for the 10th Congressional District, grew up near Washington, D.C., as the daughter of two public school teachers. She served as an intelligence officer in the Texas Army National Guard and U.S. Army Reserve, participating in full-time missions supporting disaster response, border operations, and public health programs. Early in her career, Rourk engaged in bipartisan public policy work focused on deficit reduction and energy security, later leading corporate communications at Dell Technologies. A resident of Central Texas for over a decade, she lives in the Eanes Independent School District, where her children attend public school. Rourk is the Democratic nominee running to represent Texas's 10th Congressional District in the 2026 election, winning her primary with more than 60% of the vote for an open seat created by the retirement of long-serving Republican Representative Michael McCaul. The newly drawn district encompasses 13 counties, stretching from the Houston suburbs through rural East Texas to northern Austin. Positioning herself as a pragmatic problem solver and servant leader, Rourk has centered her campaign on grassroots door-knocking, deep organizing, and restoring accountability through proposals such as mandating regular open town halls in every congressional district.
== Chart performance == "Chains of Love" became Erasure's sixth consecutive top 20 hit on the UK Singles Chart, just missing the top 10 by peaking at number 11. In the United States, it became Erasure's mainstream breakthrough by climbing to number 12 on the Billboard Hot 100 and becoming the group's first entry on the Billboard Modern Rock Tracks chart. It also hit number four on the Billboard Hot Dance Music/Club Play chart. "Chains of Love" remains Erasure's highest-charting single in the United States.
On 2 December 2025, the Southern Transitional Council (STC) launched a large-scale offensive with a force of 10,000 fighters against Yemeni government positions in the Hadhramaut Governorate, eventually expanding into the Al-Mahrah Governorate and other adjacent governorates. By 8 December, STC forces had seized control of nearly all the governorates that were once part of South Yemen, in addition to Dhale Governorate, including the entire southern coastline of Yemen, the border region with Oman, and the oil fields in Hadhramaut Governorate. The STC claimed control over all 8 governorates by 9 December. By 9 December, STC forces were estimated to control 90–95% of the populated areas in the former South Yemen, in addition to holding at least 80% of Yemen's proven oil reserves. Of all the regions seized by the STC, the Hadhramaut Governorate was the most strategically valuable one by far. This was seen as marking a major victory for the UAE, and a significant setback for Saudi ambitions in the region, as it could have provided the conditions for the STC eventually declaring the secession of southern Yemen. During the offensive, Saudi Arabia withdrew its remaining forces from Aden and Aden International Airport. Tensions escalated further in late December. Saudi Arabia demanded STC withdrawal from the seized territories and conducted airstrikes on STC positions starting 26 December, including reported strikes in Wadi Nahb (Hadhramaut) and later on a port shipment in Mukalla alleged to contain UAE-supplied weapons.
== Precautions == Promethium, similar to most other lanthanides, has no biological role. Promethium-147 can emit gamma rays, which are dangerous for all lifeforms, during its beta decay.⟨Simmons1964⟩ Interactions with tiny quantities of promethium-147 are not hazardous if certain precautions are observed.⟨Army1987⟩ In general, gloves, footwear covers, safety glasses, and an outer layer of easily removed protective clothing should be used.⟨Pmlist⟩ It is not known what human organs are affected by interaction with promethium; a possible candidate is the bone tissues. Sealed promethium-147 is not dangerous. However, if the packaging is damaged, then promethium becomes dangerous to the environment and humans. If radioactive contamination is found, the contaminated area should be washed with water and soap, but, even though promethium mainly affects the skin, the skin should not be abraded. If a promethium leak is found, the area should be identified as hazardous and evacuated, and emergency services must be contacted. No dangers from promethium aside from the radioactivity are known.
PUFA-fortified foods available on the market have been increasing since epidemiological and clinical researches have revealed possible effects of PUFA on brain development and curative and/or preventive effects on cardiovascular disease. However, PUFA are very labile and easily oxidizable, thus the maximum beneficial effects of PUFA supplements may not be obtained if they contain significant amounts of toxic OαβUAs, which as commented on above, are being considered as possible causal agents of numerous diseases. Special attention must also be paid to cooking oils used repeatedly in catering and households because in those processes very high amounts of OαβUAs are generated and they can be easily absorbed through the diet.
Sources: en.wikipedia.org
== Overdose == Overdosage leads to drowsiness, agitation, nausea and anticholinergic effects like tachycardia (high heart rate), dry mouth, blurred vision, glaucoma, or urinary retention. Especially in children, pentoxyverine can cause hypoventilation, but much more seldom than codeine and other opioid antitussives. The treatment of overdosage aims at the symptoms; there are no specific antidotes available.
This diagram represents the biosynthetic and metabolic pathways by which phytocannabinoids (e.g., CBD, THC, CBN) are created in the cannabis plant. Starting with CBG-A, the acidic forms of certain phytocannabinoids are generated via enzymatic conversion. From there, decarboxylation (i.e., catalyzed by combustion or heat) yields the most well-known metabolites present in the cannabis plant. CBN is unique in that it does not arise from a pre-existing acidic form, but rather is generated through the oxidation of THC. CBN is unique among phytocannabinoids in that its biosynthetic pathway involves conversion directly from Δ9-THC, rather than from an acidic precursor form of CBN (e.g., Δ9-THC arises through decarboxylation of THC-A). CBN can be found in trace amounts in the Cannabis plant, found mostly in cannabis that is aged and stored, allowing for CBN formation through the oxidation of the cannabis plant's main psychoactive and intoxicating chemical, tetrahydrocannabinol (THC). This process of oxidation occurs via exposure to heat, oxygen, and/or light. Although reports are limited, CBN-A has also been measured at very low levels in the cannabis plant, thought to have formed via hydrolyzation of THC-A (see Phytocannabinoid Biosynthesis diagram, below).
Absorption spectroscopy techniques (e.g., FTIR, ultraviolet-visible ("UV-vis") spectroscopy) measure how much light a sample absorbs at each wavelength. The most straightforward way to do this, the "dispersive spectroscopy" technique, is to shine a monochromatic light beam at a sample, measure how much of the light is absorbed, and repeat for each different wavelength. The dispersive spectroscopy technique is used by some UV–vis spectrometers to take measurements. Fourier transform spectroscopy is a less intuitive way to obtain the same information. Rather than shining a monochromatic beam of light (a beam composed of only a single wavelength) at the sample, this technique shines a beam containing many frequencies of light at once and measures how much of that beam is absorbed by the sample. Next, the beam is modified to contain a different combination of frequencies, giving a second data point. This process is rapidly repeated many times over a short time span. Afterwards, a computer takes all this data and works backward to infer what the absorption is at each wavelength. The beam described above is generated by starting with a broadband light source—one containing the full spectrum of wavelengths to be measured. The light shines into a Michelson interferometer—a certain configuration of mirrors, one of which is moved by a motor. As this mirror moves, each wavelength of light in the beam is periodically blocked, transmitted, blocked, transmitted, by the interferometer, due to wave interference.
== Applications == Alpha emitters such as actinium-225 are favored in cancer treatment because of the short range (a few cell diameters) of alpha particles in tissue and their high energy, rendering them highly effective in targeting and killing cancer cells—specifically, alpha particles are more effective at breaking DNA strands. The 10-day half-life of 225Ac is long enough to facilitate distribution, but short enough that little remains in the body months after treatment. Additionally, each decay of 225Ac to 209Bi nets four high-energy alpha particles, greatly increasing its potency. Despite its limited availability, several clinical trials have been completed, demonstrating the effectiveness of 225Ac in targeted alpha therapy. Complexes including 225Ac—such as antibodies labeled with 225Ac—have been tested to target various types of cancer, including leukemia, prostate carcinoma, and breast carcinoma in humans. For example, one experimental 225Ac-based drug has shown effectiveness against acute myeloid leukemia without harming the patient. Further clinical trials of other drugs are underway such as the SatisfACtion trial (NCT04597411), a Phase I/II, open-label, multi-center study that is evaluating 225Ac-PSMA-R2 in patients with metastatic hormone-sensitive prostate cancer (mHSPC) and metastatic castration-resistant prostate cancer (mCRPC).
Sources: en.wikipedia.org
Trials differ in patient population, dose schedule, background treatment, and the endpoints used to judge success. Many are small and single-center, so random variation can dominate the reported effects.
Authorization is limited to a small number of countries and covers specific indications such as chronic hepatitis B and vaccine adjuvant use. Availability and labelling differ by jurisdiction.
Most reviews describe it as an immunomodulatory agent with an uncertain clinical effect. They generally call for larger, better-controlled trials before firm conclusions are drawn.
Its sequence corresponds to the amino-terminal portion of prothymosin alpha, a larger protein present in many cell types. The isolated 28-residue peptide is a fragment of that protein rather than a separately encoded molecule, and laboratory material is produced by synthesis.