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Last reviewed on 2026-05-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
| 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 |
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.
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.
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.
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。
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。
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.
=== Thermal === Its thermal properties enable it to be used as the barrier material in some fire-resistant safes. It is also used in evacuated powder insulation for use with cryogenics. Diatomaceous earth powder is inserted into the vacuum space to aid in the effectiveness of vacuum insulation. It was used in the classical AGA cookers as a thermal heat barrier.
Erythropoietins available for use as therapeutic agents are produced by recombinant DNA technology in cell culture, and include Epogen/Procrit (epoetin alfa) and Aranesp (darbepoetin alfa); they are used in treating anemia resulting from chronic kidney disease, chemotherapy induced anemia in patients with cancer, inflammatory bowel disease (Crohn's disease and ulcerative colitis) and myelodysplasia from the treatment of cancer (chemotherapy and radiation). The package inserts include boxed warnings of increased risk of death, myocardial infarction, stroke, venous thromboembolism, and tumor recurrence, particularly when used to increase the hemoglobin levels to more than 11 g/dL to 12 g/dL.
In the United States, heroin is not accepted as medically useful. Its classification as a Schedule I drug means it has "no currently accepted medical use and a high potential for abuse." Under the generic name diamorphine, heroin is prescribed as a strong pain medication in the United Kingdom, where it is administered via oral, subcutaneous, intramuscular, intrathecal, intranasal or intravenous routes. It may be prescribed for the treatment of acute pain, such as in severe physical trauma, myocardial infarction, post-surgical pain and chronic pain, including end-stage terminal illnesses. In other countries it is more common to use morphine or other strong opioids in these situations. The UK's National Institute for Health and Clinical Excellence has produced guidance on the management of caesarean section, which recommends the use of intrathecal or epidural diamorphine for post-operative pain relief. For women who have had intrathecal opioids including diamorphine, there should be a minimum hourly observation of respiratory rate, sedation and pain scores for at least 12 hours if risk factors for respiratory depression are present. Women should be offered diamorphine (up to 0.3mg intrathecally) for intra- and postoperative analgesia because it reduces the need for supplemental analgesia after a caesarean section. Epidural diamorphine (up to 3mg) is a suitable alternative. Diamorphine continues to be widely used in palliative care in the UK, where it is commonly given by the subcutaneous route, often via a syringe driver if patients cannot easily swallow morphine solution.
Lipases hydrolyze fats and oils with subsequent release of free fatty acids such as diacylglycerols, monoacylglycerols and glycerol. Lipases have been involved in biotechnology applications because of its ability to catalyze synthetic reactions in non-aqueous solutions. One study has reported the expression of a fungal 11 alpha-steroid hydroxylase from R. oryzae which can be used to perform the 11 alpha-hydroxylation of the steroid skeleton which has simplified steroid drug production.R. oryzae can produce intracellular ribonuclease in a metal ion-regulated liquid medium with the addition of calcium and molybdenum stimulating ribonuclease production. R. oryzae strain ENHE isolated from contaminated soil was found to be capable of tolerating and removing pentachlorophenol. R. oryzae is known to produce L (+)-lactic acid because the fungus cells possess better resistance to high concentration of accumulated lactic acid and lower content of nutrient requirement compared to the commonly used bacterial procedures. Thus, R. oryzae is the most efficient approached to improve lactic acid production process that facilitates multiple reuses of fungal cells for long-term lactic acid production. Ethanol is the main by-product in the fermentation process of R. oryzae during the production of L-lactic acid. R. oryzae can be used as a biocatalyst for ester production in organic solvent. Dry mycelium of four R. oryzae strains proved effective for catalysing the synthesis of different flavor esters.
Sources: en.wikipedia.org
=== Porosity of aerogel === There are several ways to determine the porosity of aerogel: the three main methods are gas adsorption, mercury porosimetry, and scattering method. In gas adsorption, nitrogen at its boiling point is adsorbed into the aerogel sample. The gas being adsorbed is dependent on the size of the pores within the sample and on the partial pressure of the gas relative to its saturation pressure. The volume of the gas adsorbed is measured by using the Brunauer, Emmit and Teller formula (BET), which gives the specific surface area of the sample. At high partial pressure in the adsorption/desorption the Kelvin equation gives the pore size distribution of the sample. In mercury porosimetry, the mercury is forced into the aerogel porous system to determine the pores' size, but this method is highly inefficient since the solid frame of aerogel will collapse from the high compressive force. The scattering method involves the angle-dependent deflection of radiation within the aerogel sample. The sample can be solid particles or pores. The radiation goes into the material and determines the fractal geometry of the aerogel pore network. The best radiation wavelengths to use are X-rays and neutrons. Aerogel is also an open porous network: the difference between an open porous network and a closed porous network is that in the open network, gases can enter and leave the substance without any limitation, while a closed porous network traps the gases within the material forcing them to stay within the pores.
Herein, the electron donor NADPH is used as the reducing agent, ultimately converting the β-keto group of β-ketoacyl-ACP into the β-hydroxyl group of β-hydroxyacyl-ACP. The fifth step of fatty acid elongation is the dehydration of β-hydroxyacyl-ACP to enoyl-ACP, in a reaction catalyzed by 3-hydroxyacyl-ACP dehydratase. 3-hydroxyacyl-ACP dehydratase removes one molecule of H2O to form a double bond between the C2–C3 carbons of β-hydroxyacyl-ACP, thereby saturating the chain and producing enoyl-ACP. The sixth step of fatty acid elongation is the reduction of enoyl-ACP to butyryl-ACP, in a reaction catalyzed by enoyl-ACP reductase. Herein, enoyl-ACP reductase reduces the C2–C3 double bond of enoyl-ACP into a saturated acyl-ACP using one molecule NADPH as the electron donor. The production of butyryl-ACP thus marks the completion of the first cycle of fatty acid elongation, and the reaction sequence thereafter repeats again (condensation → reduction → dehydration → reduction). At the beginning of the second cycle, butyryl-ACP condenses with a molecule of malonyl-ACP, forming the six-carbon β-ketoacyl-ACP molecule and one molecule of CO2. The next three reactions within the second cycle (reduction → dehydration → reduction) convert the six-carbon β-ketoacyl-ACP into a six-carbon ACP molecule, which thus marks the completion of the second cycle of fatty acid elongation, and a third cycle can thereafter begin. These elongation cycles continue (x7) until a (16C) acyl-ACP molecule is formed.
The Rockefeller Foundation continued funding German eugenics research even after it was clear that it was being used to rationalize discrimination against Jewish people and other groups, after the Nuremberg laws in 1935. In 1936, Rockefeller fulfilled pledges of $655,000 to Kaiser Wilhelm Institute, even though several distinguished Jewish scientists had been dropped from the institute at the time. The Rockefeller Foundation did not alert the world about the racist implications of Nazi ideology, but furthered and funded eugenic research through the 1930s. Even into the 1950s, Rockefeller continued to provide some funding for research borne out of German eugenics. The foundation also funded the relocation of scholars threatened by the Nazis to America in the 1930s, known as the Refugee Scholar Program and the Emergency Committee in Aid of Displaced Foreign Scholars. Some of the notable figures relocated or saved, among a total of 303 scholars, were Thomas Mann, Claude Lévi-Strauss and Leó Szilárd. The foundation helped The New School provide a haven for scholars threatened by the Nazis.
mitochondrion (pl.) mitochondria; also formerly chondriosome. A highly pleiomorphic membrane-bound organelle found in the cytoplasm of nearly all eukaryotic cells, usually in large numbers in the form of sausage-shaped structures 5–10 micrometres in length, enclosed by a double membrane, with the inner membrane infolded in an elaborate series of cristae so as to maximize surface area. Mitochondria are the primary sites of ATP synthesis, where ATP is regenerated from ADP via oxidative phosphorylation, as well as many supporting pathways, including the citric acid cycle and the electron transport chain. Like other plastids, mitochondria contain their own genome encoded in circular DNA molecules which replicate independently of the nuclear genome, as well as their own unique set of transcription factors, polymerases, ribosomes, transfer RNAs, and aminoacyl-tRNA synthetases with which to direct transcription and translation of their genes. The majority of the structural proteins found in mitochondria are encoded by nuclear genes, however, such that mitochondria are only partially autonomous. These observations suggest mitochondria evolved from symbiotic prokaryotes living inside eukaryotic cells.
Phlebotonics of heterogeneous composition, consisting partly of citrus peel extracts (flavonoids, such as hesperidin) and synthetic compounds, are used to treat chronic venous insufficiency and hemorrhoids. Some are non-prescription dietary supplements, such as diosmin, while one other – Vasculera (Diosmiplex) – is a prescription medical food intended for treating venous disorders. Their mechanism of action is undefined, and clinical evidence of benefit for using phlebotonics to treat venous diseases is limited.
Sources: en.wikipedia.org
Proteases are a group of enzymes that show a broad range of cleavage specificities. Promiscuous proteases as digestive enzymes unspecifically degrade peptides, whereas highly specific proteases are involved in signaling cascades.
== Applications == The simplicity and efficiency of MEKC have made it an attractive technique for a variety of applications. Further improvements can be made to the selectivity of MEKC by adding chiral selectors or chiral surfactants to the system. Unfortunately, this technique is not suitable for protein analysis because proteins are generally too large to partition into a surfactant micelle and tend to bind to surfactant monomers to form SDS-protein complexes. Recent applications of MEKC include the analysis of uncharged pesticides, essential and branched-chain amino acids in nutraceutical products, hydrocarbon and alcohol contents of the marjoram herb. MEKC has also been targeted for its potential to be used in combinatorial chemical analysis. The advent of combinatorial chemistry has enabled medicinal chemists to synthesize and identify large numbers of potential drugs in relatively short periods of time. Small sample and solvent requirements and the high resolving power of MEKC have enabled this technique to be used to quickly analyze a large number of compounds with good resolution. Traditional methods of analysis, like high-performance liquid chromatography (HPLC), can be used to identify the purity of a combinatorial library, but assays need to be rapid with good resolution for all components to provide useful information for the chemist. The introduction of surfactant to traditional capillary electrophoresis instrumentation has dramatically expanded the scope of analytes that can be separated by capillary electrophoresis.
Social work in mental health, also called psychiatric social work, is a process where an individual in a setting is helped to attain freedom from overlapping internal and external problems (social and economic situations, family and other relationships, the physical and organizational environment, psychiatric symptoms, etc.). It aims for harmony, quality of life, self-actualization and personal adaptation across all systems. Psychiatric social workers are mental health professionals that can assist patients and their family members in coping with both mental health issues and various economic or social problems caused by mental illness or psychiatric dysfunctions and to attain improved mental health and well-being. They are vital members of the treatment teams in Departments of Psychiatry and Behavioral Sciences in hospitals. They are employed in both outpatient and inpatient settings of a hospital, nursing homes, state and local governments, substance use clinics, correctional facilities, health care services, private practice, etc. In the United States, social workers provide most of the mental health services. According to government sources, 60 percent of mental health professionals are clinically trained social workers, 10 percent are psychiatrists, 23 percent are psychologists, and 5 percent are psychiatric nurses. Mental health social workers in Japan have professional knowledge of health and welfare and skills essential for person's well-being.
Cells are capable of synthesizing new proteins, which are essential for the modulation and maintenance of cellular activities. This process involves the formation of new protein molecules from amino acid building blocks based on information encoded in DNA/RNA. Protein synthesis generally consists of two major steps: transcription and translation. Transcription is the process where genetic information in DNA is used to produce a complementary RNA strand. This RNA strand is then processed to give messenger RNA (mRNA), which is free to migrate into the cytoplasm. mRNA molecules bind to protein-RNA complexes called ribosomes located in the cytosol, where they are translated into polypeptide sequences. The ribosome mediates the formation of a polypeptide sequence based on the mRNA sequence. The mRNA sequence directly relates to the polypeptide sequence by binding to transfer RNA (tRNA) adapter molecules in binding pockets within the ribosome. The new polypeptide chain then folds into a functional three-dimensional protein molecule.
== Trade == South Korea spent around $129 million in 2017 to purchase 275,000 metric tons of foreign kimchi, more than 11 times the amount it exported, according to data released by the Korea Customs Service in 2017. South Korea consumes 1.85 million metric tons of kimchi annually, or 36.1 kg per person. It imports a significant fraction of that, mostly from China, and runs a $47.3 million kimchi trade deficit.
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.
Thymosin fraction 5 is a mixture of many peptides obtained from thymus tissue, while thymosin alpha 1 is a single defined 28-residue molecule. The two names appear together in older literature because the purified peptide was first obtained from that mixture.