immunomodulation 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 2026-02-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
The name itself causes confusion, because several unrelated thymic peptides share the thymosin label. Thymosin beta-4, for example, is a different molecule with different functions. Naming conventions in the literature also mix descriptive research terms with assigned nonproprietary names, so a reader should confirm which entity a given paper addresses. Clarifying that point is usually the first step in interpreting any claim about this peptide.
Thymosin alpha-1 is a short peptide of 28 amino acid residues first described in the 1970s as a component of thymic extracts. Its N-terminal residue carries an acetyl group, and the sequence is highly conserved across mammalian species. The peptide is not encoded as a standalone gene product; it is released by proteolytic cleavage from the N-terminus of prothymosin alpha, a larger acidic nuclear protein. That precursor relationship places it within a broader family of thymic and immune-associated peptides that have been studied for decades.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Residue count | 28 amino acids | Acetyl group on the first residue |
| Approximate molecular mass | 3108 daltons | Calculated from the consensus sequence |
| Origin | Cleavage product of prothymosin alpha | Not encoded as a separate gene product |
| Primary research focus | Immune modulation | Studied in viral hepatitis and as a vaccine adjuvant |
| Common synonyms | Thymalfasin, Tα1, thymosin alpha 1 | Thymalfasin is the assigned nonproprietary name |
Lyophilized thymosin alpha-1 is generally stored at or below minus twenty degrees Celsius, protected from moisture and light. Short-term handling at ambient temperature is possible for dry powder, but reconstituted solutions degrade faster and are usually kept at two to eight degrees Celsius with a defined expiry of days rather than weeks. Repeated freeze-thaw cycles should be avoided because they promote aggregation and loss of potency. Exact limits depend on the formulation and should follow the supplier's documentation.
Identity and purity are normally assessed by reversed-phase high-performance liquid chromatography, which separates the peptide from related impurities and truncation products. Mass spectrometry confirms molecular mass and detects modifications such as deamidation or oxidation. Amino acid analysis and peptide mapping provide additional sequence-level confirmation. For research material, a certificate of analysis typically reports these results together with water content and counter-ion identity, since the lyophilized powder is often supplied as an acetate or trifluoroacetate salt.
Several factors accelerate degradation: alkaline pH, elevated temperature, exposure to oxidants, and the presence of residual moisture. Deamidation of asparagine residues and oxidation of methionine are the most commonly reported degradation routes. Because the peptide lacks disulfide bonds, it does not undergo the thiol-related aggregation seen in some other biologics, but physical aggregation can still occur at high concentration. Stability data are product-specific, and extrapolating shelf life between formulations is not reliable.
Thymosin alpha 1 is a synthetic 28-amino-acid peptide first isolated in 1966 from thymosin fraction 5, a bovine thymus extract. Its chain begins with an acetylated serine residue and ends with asparagine. The native peptide carries a molecular mass near 3,108 daltons. Researchers classify it as an immunomodulatory agent rather than a hormone with a single endocrine target. Early work framed it as a thymus-derived factor that supports T-cell maturation. The synthetic form used in research and clinical products matches the natural sequence.
Immune signaling studies link thymosin alpha 1 to Toll-like receptor pathways, particularly TLR2 and TLR9, on dendritic cells and other antigen-presenting cells. Activation of these receptors promotes maturation of T cells and increases natural killer cell activity. The peptide shifts cytokine output toward a T helper 1 profile, raising interferon gamma and interleukin 2 while modulating interleukin 10. Whether these effects translate into clinical benefit for any specific disease remains a subject of debate. Reported outcomes vary across trials and populations.
Thymosin alpha 1 is approved as a medicine in several countries, including Italy and China, for indications such as chronic hepatitis B and as an immune adjuvant. It is not approved by the United States Food and Drug Administration as a therapeutic product. In research settings the peptide appears in studies of sepsis, vaccine response, and oncology support, often with mixed or inconclusive results. The evidence base is uneven, and reviews note that many trials were small. Regulatory status therefore differs widely between jurisdictions.
Identity and purity are assessed mainly by reversed-phase high-performance liquid chromatography, which separates the peptide from closely related impurities and from truncated or oxidized variants. Mass spectrometry supplies the molecular mass and confirms the expected sequence length, while amino acid analysis can be used to check composition. Because the molecule has no chromophore beyond the peptide backbone, ultraviolet detection is typically performed at a low wavelength, where baseline interference from solvents and buffers is a practical concern. Water content and counter-ion content are often reported alongside purity.
Practical handling focuses on limiting adsorption and contamination. The peptide dissolves readily in water, and dilute solutions tend to adhere to plastic and glass surfaces, so an inert carrier protein or a defined buffer can reduce losses in laboratory work. Workers also record the counter-ion form, since an acetate or trifluoroacetate salt changes the mass balance of the weighed powder. Documentation of lot number, purity value, and storage history supports reproducibility when results from different laboratories are compared.
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。
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。
== Pharmacology == Volufralin works by increasing expression of the melanocortin MC4 receptor and of its endogenous agonist in the brain. In relation to this, its mechanism of action differs from that of earlier direct melanocortin receptor agonists like bremelanotide. As such, the drug is described as a potential first-in-class medication. Volufralin produces non-acute long-lasting pro-erectile effects in rodents and humans, with short-term dosing resulting in gradually increasing improvement that is then sustained for weeks despite cessation of dosing. The pro-erectile effects of volufralin can be reversed by a melanocortin MC4 receptor antagonist in rodents.
1936: The first all-steel reefers entered service. 1946: Two experimental aluminum-body refrigerator cars entered service on the PFE; an experimental reefer with a stainless-steel body was built for the SFRD. 1950: The U.S. refrigerator car roster dropped to 127,200. 1957: The last ice bunker refrigerator cars were built. 1958: The first mechanical reefers (using diesel-powered refrigeration units) entered revenue service. 1959: The flush, "plug" style sliding door was introduced as an option, providing a larger door to ease loading and unloading. The tight-fitting doors were better insulated, helping the car maintain a more even temperature. An early example is the DT&I XL-1 car by Evans. 1966: Japanese National Railways started operation of fish freight express trains by newly built "resa 10000" type refers. 1969: ACF constructed several experimental center flow hopper cars incorporating mechanical cooling systems and insulated cargo cells. The units were intended for shipping bulk perishables. 1971: The last ice-cooled reefers were retired. 1980: The U.S. refrigerator car roster dropped to 80,000. 1986: The last reefers in Japan were replaced by reefer containers. 1990s: The first cryogenically cooled reefers entered service. 2001: The number of refrigerator cars in the United States bottomed out at approximately 8,000. 2005: The number of reefers in the United States climbs to approximately 25,000, due to significant new refrigerator car orders. 2006: Railex launches 55-car unit train reefer service between the U.S. West Coast and New York.
In two-dimensional structures like graphene, thermal and quantum fluctuations cause relative displacement, with fluctuations growing logarithmically with structure size as per the Mermin–Wagner theorem. This shows that the amplitude of long-wavelength fluctuations grows logarithmically with the scale of a 2D structure, and would therefore be unbounded in structures of infinite size. Local deformation and elastic strain are negligibly affected by this long-range divergence in relative displacement. It is believed that a sufficiently large 2D structure, in the absence of applied lateral tension, will bend and crumple to form a fluctuating 3D structure. Researchers have observed ripples in suspended layers of graphene, and it has been proposed that the ripples are caused by thermal fluctuations in the material. As a consequence of these dynamical deformations, it is debatable whether graphene is truly a 2D structure. These ripples, when amplified by vacancy defects, induce a negative Poisson's ratio into graphene, resulting in the thinnest auxetic material known so far. Graphene-nickel (Ni) composites, created through plating processes, exhibit enhanced mechanical properties due to strong Ni-graphene interactions inhibiting dislocation sliding in the Ni matrix.
== Awards and accolades == 1984 Elected Fellow of the National Academy of Clinical Biochemistry (now FADLM) 1988 Distinguished Scientist Award, (Clinical Ligand Assay Society) 1990-92 Co-Editor-in-Chief, Clinical Biochemistry 1996-97 President, International Clinical Ligand Assay Society 1998 Doctor of Medicine honoris causa (Leopold-Franzens-Universität Innsbruck, Austria) 1998 University of Louisville Symposium honoring the career of James L. Wittliff 2001 American Association for Clinical Chemistry (Award for Outstanding Contributions to Clinical Chemistry in a Selected Area of Research) 2001 American Association for Clinical Chemistry (Hall of Fame recognition) 2002 Interagency Coordinating Committee on the Validation of Alternative Methods/ National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods- Expert Panel 2004 Goldsmith Research Excellence Award, American Cancer Society, Kentucky Division 2008 President's Award for Career Achievements: Outstanding Scholarship, Research and Creative Activity, University of Louisville 2011 Interagency Coordinating Committee on the Validation of Alternative Methods/ National Toxicology Program Independent Scientific Peer Review Panel for the Evaluation of the LUMI-CELL® ER (BG1Luc ER TA) Test Method 2012 The CPT Paul W. Peña Outstanding Alumni Award - San Marcos Academy, San Marcos, TX 2014 Morton K.
Sources: en.wikipedia.org
=== Red algal derived chloroplasts === Secondary chloroplasts derived from red algae appear to have only been taken up only once, which then diversified into a large group called chromists or chromalveolates. Today they are found in the haptophytes, cryptomonads, heterokonts, dinoflagellates and apicomplexans (the CASH lineage). Red algal secondary chloroplasts usually contain chlorophyll c and are surrounded by four membranes. However, chromist monophyly has been rejected, and it is considered more likely that some chromists acquired their plastids by incorporating another chromist instead of inheriting them from a common ancestor. Cryptophytes seem to have acquired plastids from red algae, which were then transmitted from them to both the Heterokontophytes and the Haptophytes, and then from these last to the Myzozoa.
Carefully designing the sequences of the staple strands enables scientists to precisely direct the scaffold strand's folding into a predetermined shape with high precision. On a chemical level, the hydrogen bonds that exist between the complementary base pairs provide strength and stability to the folded DNA origami structures. Additionally, DNA is a relatively stable molecule, offering resilience in physiological conditions. One of the advantages of using a DNA origami nanostructure over an otherwise classified DNA nanostructure is the ease of defining finite structures. In the design of some other DNA nanostructures, it can be impractical to design an extremely large number of individualized strands if the entire structure is composed of smaller strands. One method of bypassing the need for a huge number of different strands is to use repeating units, which comes with the disadvantage of a distribution of sizes and sometimes shapes. DNA Origami, however, forms discrete structures. Applications for DNA origami are primarily focused around the ability to exert fine control on systems, especially by constraining positions of molecules, typically by attachment to the DNA origami nanostructures. Current applications are primarily focused on sensing and drug delivery, but many additional applications have been investigated.
The Times reported that while one child in 20 in Shanghai could have kidney damage as a result of drinking contaminated formula milk, on the other hand, "like the emperors of old, the new communist elite enjoy the finest produce from all over China, sourced by a high-security government department." Access Asia, a Shanghai-based consumer consultancy, said Fonterra was an example of western executives in China "believ[ing] advice in business books that they must avoid making their local partners 'lose face' at all costs". It suggested that Fonterra paid the price for this both financially and in damage to their reputation. Caijing said the crisis revealed that there had been a "serious dereliction of duty" at the AQSIQ, and that the government had failed as a "night watchman". Citing public consensus that government should limit itself to a supervisory role, it urged the construction of a regulatory system which addressed the role of regulators watching over the production process, avoiding over-regulation, 'regulatory capture' and abuse of power by regulators. "Keeping the market in order and ensuring independent law enforcement should be part of the mandate."
Sources: en.wikipedia.org
== History == Potassium sulfate (K2SO4) has been known since early in the 14th century. It was studied by Glauber, Boyle, and Tachenius. In the 17th century, it was named arcanuni or sal duplicatum, as it was a combination of an acid salt with an alkaline salt. It was also known as vitriolic tartar and Glaser's salt or sal polychrestum Glaseri after the pharmaceutical chemist Christopher Glaser who prepared it and used medicinally. Known as arcanum duplicatum ("double secret") or panacea duplicata in pre-modern medicine, it was prepared from the residue (caput mortuum) left over from the production of aqua fortis (nitric acid, HNO3) from nitre (potassium nitrate, KNO3) and oil of vitriol (sulphuric acid, H2SO4) via Glauber's process:
Disney films are usually co-directed and some directors have served on several winning teams: Wilfred Jackson, Hamilton Luske, Clyde Geronimi, David Hand, Ben Sharpsteen, Wolfgang Reitherman and Bill Roberts have all co-directed at least two films on the list. Only seven directors have topped the chart in consecutive years: McCarey (1944 and 1945), Nichols (1966 and 1967), Spielberg (1981 and 1982), Jackson (2002 and 2003), Verbinski (2006 and 2007) and the Russo brothers (2018 and 2019). Because of release schedules—especially in the case of films released towards the end of the year—and different release patterns across the world, many films can do business in two or more calendar years; therefore the grosses documented here are not confined to just the year of release. Grosses are not limited to original theatrical runs either, with many older films often being re-released periodically so the figures represent all the business a film has done since its original release; a film's first-run gross is included in brackets after the total if known. Because of incomplete data, it cannot be known for sure how much money some films have made and when they made it, but generally the chart chronicles the films from each year that went on to earn the most. In the cases where estimates conflict both films are recorded, and in cases where a film has moved into first place because of being re-released the previous record-holder is also retained.
== Childhood and education == Joseph Fruchtgarten was born in Częstochowa, Poland; his father Shama Nuta (Charles) Fruchtgarten was a grain merchant, and his mother Ella (Aisenstadt) Fruchtgarten was a French teacher. Like many other Polish Jews, the Fruchtgartens immigrated to the United States shortly before the outbreak of World War I. They lived in New York City from 1913 to 1917, and in April 1917 they moved to Minsk (then occupied by the Red Army in the midst of the Russian Civil War). Between 1917 and 1923, Fruchtgarten attended school intermittently, moving from Minsk to Siedlce to Warsaw to Berlin, and learning French, German and Latin (in addition to Polish and English). In 1923, the Fruchtgartens returned to New York and changed their name to Fruton to avoid being targets of anti-Semitism. Joseph Fruton followed his father in rejecting religion, but learned early on "not to advertise either [his] Jewishness or [his] atheism." After a few months at De Witt Clinton High School, Fruton joined the first class of students at James Madison High School. He graduated in 1927, excelling particularly in chemistry. He applied to Columbia University, and after an initial rejection—possibly because he was only 15 at the time, possibly because the school had already admitted the quota of New York Jews—his mother convinced an admissions official to reverse the decision. Inspired by the character Max Gottlieb from the Sinclair Lewis novel Arrowsmith, Fruton planned his Columbia education around becoming a scientist. The lectures and lab-work of organic chemist John M.
Sources: en.wikipedia.org
It is usually classified as an immunomodulatory peptide rather than a classical hormone. It derives from the larger protein prothymosin alpha and acts mainly on immune cells. The thymosin label covers a group of distinct peptides, so the naming can be misleading.
The two share a family name but have different sequences, sizes, and functions. Thymosin beta-4 is a 43-residue peptide associated with actin binding and cell migration. Thymosin alpha-1 is a 28-residue peptide linked mainly to immune signaling.
Thymalfasin is the assigned international nonproprietary name for the synthetic 28-residue peptide. Thymosin alpha-1 is the descriptive research name for the same molecule. Which term appears depends on the context and the regulatory document.
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.