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Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or chemically modified byproducts. Mass spectrometry confirms the expected molecular mass and can indicate acetylation state or sequence errors. Amino acid analysis and peptide mapping supply complementary sequence-level information, while endotoxin testing is relevant for preparations intended for cell or animal work. Purity figures reported by suppliers refer to the method used and are not directly comparable across laboratories unless conditions are stated.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white lyophilized powder | Visual description varies by batch |
| Solubility | Freely soluble in water | Aqueous buffers are commonly used |
| Typical storage temperature | -20 °C or below for powder | Reconstituted liquid kept at 2-8 °C short term |
| Purity method | Reversed-phase HPLC | Value derived from peak area integration |
| Identity method | Mass spectrometry | Confirms mass and sequence integrity |
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 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.
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 Court of Criminal Appeal reduces the sentence of teenager Daniel Haig, sentenced to life imprisonment for the 2021 murder of Justin McLaughlin, himself a teenager. Haig will now be required to serve 13 rather than 16 years before becoming eligible to be considered for parole following an appeal against the original sentence handed out in August 2023. A pod of 77 whales dies after washing ashore on a beach in Orkney in what is believed to be the largest incident of its kind for several decades. 12–16 July – 2024 World Orienteering Championships at Edinburgh 13 July – Staff at Five Sisters Zoo confirm the death of Yampil, a black Asiatic bear who was rehomed from an abandoned zoo in Ukraine in January. 15 July – Figures show Edinburgh City Council issued over 6,000 low emission zone fines since the city's low emission zone was introduced.
== Function == Fasciae were traditionally thought of as passive structures that transmit mechanical tension generated by muscular activities or external forces throughout the body. An important function of muscle fasciae is to reduce friction of muscular force. In doing so, fasciae provide a supportive and movable wrapping for nerves and blood vessels as they pass through and between muscles. In the tradition of medical dissections it has been common practice to carefully clean muscles and other organs from their surrounding fasciae in order to study their detailed topography and function. However, this practice tends to ignore that many muscle fibers insert into their fascial envelopes and that the function of many organs is significantly altered when their related fasciae are removed. This insight contributed to several modern biomechanical concepts of the human body, in which fascial tissues take over important stabilizing and connecting functions, by distributing tensional forces across several joints in a network-like manner similar to the architectural concept of tensegrity. Starting in 2018 this concept of the fascial tissue serving as a body-wide tensional support system has been successfully expressed as an educational model with the Fascial Net Plastination Project. Fascial tissues – particularly those with tendinous or aponeurotic properties – are also able to store and release elastic potential energy.
Similarly, altered somatosensory integration and introspection may relate to abnormal body image. A review of functional neuroimaging studies reported reduced activations in "bottom up" limbic region and increased activations in "top down" cortical regions which may play a role in restrictive eating. Compared to controls, people who have recovered from anorexia show reduced activation in the reward system in response to food, and reduced correlation between self reported liking of a sugary drink and activity in the striatum and anterior cingulate cortex. Increased binding potential of 11C radiolabelled raclopride in the striatum, interpreted as reflecting decreased endogenous dopamine due to competitive displacement, has also been observed. Structural neuroimaging studies have found global reductions in both gray matter and white matter, as well as increased cerebrospinal fluid volumes. Regional decreases in the left hypothalamus, left inferior parietal lobe, right lentiform nucleus and right caudate have also been reported in acutely ill patients. However, these alterations seem to be associated with acute malnutrition and largely reversible with weight restoration, at least in nonchronic cases in younger people. In contrast, some studies have reported increased orbitofrontal cortex volume in currently ill and in recovered patients, although findings are inconsistent. Reduced white matter integrity in the fornix has also been reported.
Double-A (officially Class AA) is the second-highest level of play in Minor League Baseball in the United States since 1946, below only Triple-A. There are 30 teams classified at the Double-A level, one for each team in Major League Baseball, organized into three leagues: the Eastern League, the Southern League, and the Texas League.
== Career == Tew was appointed the G. Willing Chair in Cancer Research at the Medical University of South Carolina from 1999 to 2004. He was the Director of the Developmental Cancer Therapeutics Program at Hollings Cancer Center from 2004 to 2019, and serves as a professor in the Department of Cell & Molecular Pharmacology at the Medical University of South Carolina. Tew has been the John C. West Chair in Cancer Research at the Medical University of South Carolina since 2004. Tew held the position of Associate Editor from 1993 to 2007 and later assumed the role of Senior Editor in the Experimental Therapeutics, Molecular Targets, and Chemical Biology Section from 2007 to 2018 for the journal Cancer Research. Concurrently, he held editorial positions including, Editor for Cellular Pharmacology, and Editor-in-Chief of Journal of Pharmacology and Experimental Therapeutics. Tew has been the Editor (USA) of Biomedicine & Pharmacotherapy since 2002 and Serial Editor for Advances in Cancer Research since 2011. Additionally, he has held appointments at InVaMet Therapeutics and the Greehey Children's Cancer Research Institute Scientific External Advisory Board since 2019.
Sources: en.wikipedia.org
Leucine-rich repeats and death domain containing, also known as LRDD or p53-induced protein with a death domain (PIDD), is a protein which in humans is encoded by the LRDD gene. The leucine-rich repeat (LRR), first identified by Patthy, is a domain involved in protein-protein interactions and is present in numerous proteins that serve a variety of cellular roles. Leucine-rich repeats (LRR) proteins in eukaryotic cells are found in the nucleus, cytoplasm, extracellular matrix and plasma membrane.
Reformist Mikhail Gorbachev, General Secretary of the Communist Party of the Soviet Union, also wished to reduce defence expenditures, including the enormous open-ended commitment of military aid to FAPLA, and was more open to a political settlement accordingly.
=== Dopamine === Dopamine is a neurotransmitter that regulates arousal, motivation, muscular coordination, and endurance performance, among other things. Dopamine levels have been found to be lower after prolonged exercise. A decrease in dopamine can decrease athletic performance as well as mental motivation. Dopamine itself cannot cross the blood brain barrier and must be synthesized within the brain. In rats bred for running, increased activity of the ventral tegmental area have been observed, and VTA activity correlates with voluntary wheel running. As the VTA is an area dense in dopaminergic neurons that project to many areas of the brain, this suggests that dopaminergic neurotransmission drives physical performance. Further supporting this theory is the fact that dopamine reuptake inhibitors as well as norepinephrine dopamine reuptake inhibitors are able to increase exercise performance, especially in the heat.
== Risks == CJC-1295 was under investigation for the treatment of lipodystrophy and growth hormone deficiency and reached phase II clinical trials but was discontinued upon the death of one of the trial subjects. The attending physician of the trial believed that the most likely explanation for the incident was that the patient had asymptomatic coronary artery disease with plaque rupture and occlusion, and that the occurrence was unrelated to treatment with CJC-1295. Research was terminated nonetheless as a precaution.
Sources: en.wikipedia.org
== Regulatory harmonization == In an effort to reduce the burden on manufacturers applying for orphan drug status, the FDA and the European Medicines Agency (EMA) agreed in late 2007 to utilize a common application process for both agencies. However, the two agencies will continue to maintain separate approval processes.
== Subcellular distribution == The peptide recognition domain of epiplakin is able to bind to keratins in vitro; however, in cells the epiplakin associates with keratin intermediate filaments networks only under conditions in which cellular stress is absent. Otherwise, epiplakin remains universally cytoplasmic and not bound to the intermediate filaments.
Saturated fatty acids have no C=C double bonds. They have the formula CH3(CH2)nCOOH, where n is some positive integer. An important saturated fatty acid is stearic acid (n = 16), which when neutralized with sodium hydroxide is the most common form of soap.
Sources: en.wikipedia.org
Cold storage slows the chemical degradation reactions that occur in solution. Lyophilized powder is more stable than reconstituted liquid and tolerates longer storage periods. Repeated temperature cycling should still be avoided because it can drive aggregation and loss of material.
Mass spectrometry is the standard confirmation of molecular mass and acetylation state. Chromatography establishes purity but does not identify the molecule on its own. The two techniques are normally applied together during verification.
No, because the reported value reflects the detection method and wavelength used, which vary between laboratories. A number stated without method details cannot be compared directly with another supplier's figure. Requesting the chromatogram and the method conditions is a common way to interpret it.
It corresponds to a fragment of the larger protein prothymosin alpha, which is present in many tissues. The isolated 28-amino-acid peptide was originally obtained from thymus preparations, and the pharmaceutical product is synthesized rather than extracted. The term therefore describes both a natural fragment and a manufactured drug substance.