If you have been reading about Peptide stability and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-10-02. Numbers and descriptions here follow the published literature rather than marketing material.
Thymosin alpha 1 is a 28-amino-acid peptide first isolated from thymosin fraction 5, a bovine thymic extract. Its sequence begins with an acetylated serine residue and carries a high proportion of acidic residues, so the molecule has a net negative charge near neutral pH. Despite the shared name, it is unrelated in sequence to the thymosin beta family. Synthetic material prepared by solid-phase peptide synthesis is identical in sequence to the natural peptide.
Several names appear in the literature for this peptide, including thymalfasin and the abbreviation T-alpha-1. Naming conventions differ among research articles, regulatory documents, and supplier catalogs, which complicates literature searches. Both synthetic and recombinant production routes yield a peptide with the same 28-residue sequence as the thymic isolate. Because the thymosin label also covers unrelated peptides, sources should be compared by sequence rather than by name alone.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C129H215N33O55 | Calculated for the acetylated 28-residue peptide |
| Appearance | White to off-white powder | Lyophilized solid recovered from aqueous buffer |
| Solubility | Freely soluble in water | Typically dissolved in water or buffer before use |
| Typical storage | -20 C or below, desiccated | Protect from light and avoid repeated freeze-thaw cycles |
| Identity testing | Reverse-phase HPLC with mass spectrometry | Retention time and measured mass confirm the sequence |
Routine handling calls for storage of the lyophilized powder at refrigerated temperatures, away from light, in a sealed container. Working solutions are often prepared in sterile water or buffer and kept cold between uses. Repeated freeze-thaw cycles are generally avoided because they can promote aggregation and loss of material. Laboratories usually record lot number, reconstitution date, and storage conditions so that any change in behavior can be traced to a specific preparation.
Reverse-phase high-performance liquid chromatography is the standard technique for assessing purity and concentration, because the peptide's hydrophobicity allows clean separation from related impurities. Mass spectrometry confirms molecular identity and detects sequence errors or truncations. Amino acid analysis and peptide mapping supply additional structural confirmation when required. Chromatographic purity values reported on certificates of analysis describe the proportion of the main peak and do not by themselves establish biological activity.
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。
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。
== Diagnosis == Detection of APCA (anti-parietal cell antibodies), anti-intrinsic factor antibodies (AIFA), and Helicobacter pylori (HP) antibodies in conjunction with serum gastrin are effective for diagnostic purposes.
The four substrates of this enzyme are 3-hydroxybenzoic acid, reduced nicotinamide adenine dinucleotide (NADH), oxygen and a proton. Its products are gentisic acid, oxidised NAD+, and water. The enzyme is a flavin-containing monooxygenase that uses molecular oxygen as oxidant and incorporates one of its atoms into the starting material. The systematic name of this enzyme class is 3-hydroxybenzoate,NADH:oxygen oxidoreductase (6-hydroxylating). Other names in common use include 3-hydroxybenzoate 6-hydroxylase, m-hydroxybenzoate 6-hydroxylase, and 3-hydroxybenzoic acid-6-hydroxylase. It participates in benzoate degradation via hydroxylation and uses flavin adenine dinucleotide as a cofactor.
Many exiled Poles could not return to the country for which they had fought because they belonged to political groups incompatible with the new communist regimes, or because they originated from areas of pre-war eastern Poland that were incorporated into the Soviet Union (see Polish population transfers (1944–1946)). Some were deterred from returning simply on the strength of warnings that anyone who had served in military units in the West would be endangered. Many Poles were pursued, arrested, tortured and imprisoned by the Soviet authorities for belonging to the Home Army or other formations (see Anti-communist resistance in Poland (1944–1946)), or were persecuted because they had fought on the Western front.
Sources: en.wikipedia.org
– details how the Philippine Constabulary, aided by the Scout Rangers, defeated the Huk insurgency in Central Luzon. Weir, Fraser (1998). "American Colony and Philippine Commonwealth 1901–1941". A Centennial History of Philippine Independence, 1898–1998. Archived from the original on July 24, 2020. Retrieved July 24, 2020. "IV. The Rebirth of the Army". (Title unknown).
== Description == An annual to perennial plant with creeping or erect branched stems to about 40 cm in height. The stems are square in cross-section and can vary from hairless on some plants to densely hairy on others, with a green to sometimes red or purplish colour. The leaves, which grow in opposite pairs, are narrowly oval, 2–3 cm long x 1 cm wide, downy, sparsely toothed towards the tip, and taper into a short stalk. All parts of the plant are strongly scented when crushed but it does not have noticeable glands on its surface. The small (6 mm) flowers are densely packed in whorls at the nodes, widely separated, above pairs of leaf-like bracts. The calyx is a ribbed tube about 3 mm long, with five triangular teeth, the lower two being narrower and slightly longer than the upper three; it is hairy both on the inside and the outside. The corolla has four mauve lobes or "petals" and is hairy only on the outside. The flowers are bisexual and have four long stamens, two (or all four) of which project well beyond the corolla lobes. There is one long style which is forked to produce two stigmas, which also project from the flower. The fruits consist of a cluster of four brown, 1-seeded nutlets, each about 0.7 mm long.
Under the United States Federal Analogue Act, compounds which are analogues of and "substantially similar" to Schedule I and Schedule II controlled substances may themselves be treated as Schedule I controlled substances. Consequent to this law, such substances may be considered illegal to sell, purchase, or possess. However, the law applies only if the compounds are intended for human consumption. The Federal Analogue Act has been considered "void for vagueness" as the meaning of "substantially similar" is not precisely defined. In addition, the law only applies to compounds explicitly intended for human consumption. As a result, if compounds are not marketed this way, they can still be legally sold. This has resulted in such compounds being marketed as "research chemicals", "bath salts", "plant food", and "not for human consumption", even though they actually are intended for human use. Such flaws have limited the law and led to calls for reform.
== Synthesis and degradation == Increasing cyclin D1 levels during the G1 phase is induced by mitogenic growth factors primarily through Ras-mediated pathways, and hormones. These Ras-mediated pathways lead to the increase in transcription of cyclin D1, and inhibit its proteolysis and export from the nucleus. Cyclin D1 is degraded by the proteasome upon phosphorylation of threonine 286 and subsequent ubiquitylation via the CRL4-AMBRA1 E3 ubiquitin ligase complex.
Sources: en.wikipedia.org
=== Cancer progression, tumor characterization === The mammographic density is correlated with the collagen density, thus SHG can be used for identifying breast cancer. SHG is usually coupled to other nonlinear techniques such as Coherent anti-Stokes Raman Scattering or Two-photon excitation microscopy, as part of a routine called multiphoton microscopy (or tomography) that provides a non-invasive and rapid in vivo histology of biopsies that may be cancerous.
== Iron-60 == Iron-60 has a half-life of 2.62 million years, but was thought until 2009 to have a half-life of 1.5 million years. It undergoes beta decay to 60Co, which then decays with the much shorter half-life of about 5 years to stable 60Ni. In phases of the meteorites Semarkona and Chervony Kut, a correlation between the excess concentration of 60Ni, the granddaughter isotope of 60Fe, and the abundance of the stable iron isotopes could be found, which is evidence for the existence of 60Fe at the time of formation of the Solar System. Depending on its original abundance, the energy from the decay of 60Fe may have been significant, along with that of 26Al, to the remelting and differentiation of asteroids and planetesimals after their formation. These nickel abundances in extraterrestrial materials may also provide further insight into the origin of the Solar System and its early history. Live (interstellar) iron-60 was first identified in deep sea sediments in 1999. These are deep sea ferromanganese crusts, which are constantly growing, aggregating iron, manganese, and other elements. Iron-60 has been found in fossilized bacteria in sea floor sediments. In 2019, researchers found 60Fe in Antarctica. Iron-60 shows two peaks in deep sea sediments, the first 1.7–3.2 million years ago and the second 6.5–8.7 million years ago. The peaks are related to the passage of the Solar System through the Local Bubble and likely the Orion–Eridanus Superbubble. These superbubbles were created by multiple supernovae. Traces of iron-60 have also been found in lunar samples.
Israel: GBL was classified as a proscribed substance from 2007. Netherlands: GBL is unlike GHB not listed in the narcotics law, but its distribution is controlled. Possession is not illegal but may be punished according to the Medicines Act, when intended to be sold for human consumption or synthesis of GHB. People's Republic of China: GBL was regulated as a Class III drug precursor since 7 June 2021. Poland: GBL is classified as a drug. A license is mandatory for the manufacture, processing, reworking, importing, distribution of GBL. Russia: GBL has been classified as a psychotropic substance since 22 February 2012. Its trafficking is limited, and non-licensed selling, buying or any other use is punishable by imprisonment up to 20 years. Sweden: GBL is not classified as a drug but as a health-endangering substance. Although recently passed legislation to enter into force on 1 April 2011 will make it possible to handle narcotics for industrial purposes will enable GBL and 1,4-Butanediol to be classified as controlled substances. United Kingdom: Because of their legitimate uses, regulation 4B of the 2001 regulations makes it lawful to import, export, produce, supply, offer to supply or possess GBL and 1,4-BD, except where a person does so knowing or believing that they will be used for the purpose of human ingestion. Otherwise it is a class B controlled substance. United States: GBL is regulated as a List I controlled chemical. As a GHB analog, it is also treated as a controlled substance under Schedule I of the Controlled Substances Act if intended for human consumption.
== AI Technology == In 2026, chief technology officer Mo Elshenawy described the rollout of an AI-assisted service for Hers weight-loss customers, combining AI coaches, clinicians and customer support in a single conversation. He said the system used clinical guidelines encoded in software, automated evaluation of AI responses, and escalation to human clinicians.
=== Category:EC 1.14 (act on paired donors with incorporation of molecular oxygen) === Cytochrome P450 oxidase Category:Cytochrome P450 Aromatase EC 1.14.14.1 CYP2D6 EC 1.14.14.1 CYP2E1 EC 1.14.14.1 CYP3A4 EC 1.14.14.1 Cytochrome P450 oxidase Category:EC 1.14.12 Nitric oxide dioxygenase Category:EC 1.14.13 Nitric oxide synthase EC 1.14.13.39 Category:EC 1.14.14 Aromatase EC 1.14.14.1 CYP2D6 EC 1.14.14.1 CYP2E1 EC 1.14.14.1 CYP3A4 EC 1.14.14.1 Category:EC 1.14.16 Phenylalanine hydroxylase EC 1.14.16.1 Category:EC 1.14.18 Tyrosinase EC 1.14.18.1
Sources: en.wikipedia.org
It is a 28-amino-acid peptide originally purified from a bovine thymic extract and later produced synthetically. It is studied mainly for its effects on immune cell function.
No. The two peptides share part of a name but differ in length, sequence, and net charge. Literature searches that treat them as one compound return misleading results.
Solid-phase peptide synthesis is the usual route, and recombinant expression has also been described. Both approaches produce material matching the natural sequence.
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.