If you have been reading about 合成肽 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.
Last reviewed on 2026-05-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular mass | About 3.1 kDa | 28 residues, N-terminally acetylated |
| Appearance | White to off-white powder | Lyophilized solid |
| Solubility | Freely soluble in water | Also soluble in aqueous buffers |
| Storage temperature | 2 to 8 °C | Protect from light and moisture |
| Common synonyms | Thymalfasin; Tα1 | Same peptide sequence |
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。
Storage recommendations center on low temperature, dryness, and protection from repeated freezing and thawing. The intact powder is commonly held at 20 degrees below zero Celsius or colder, while a working solution is divided into single-use aliquots to limit freeze-thaw cycles. Buffered saline or phosphate-buffered saline at neutral pH is frequently used as a diluent. Light sensitivity is not well documented, yet amber vials or foil wrapping are common practice for long-term storage of peptide stocks.
Identity and purity are assessed with a small set of standard peptide methods. Reversed-phase high-performance liquid chromatography separates the main peak from truncated or oxidized species, and its area percentage is the usual purity measure. Mass spectrometry confirms the observed molecular mass against the expected value, while amino acid analysis or peptide mapping checks composition and sequence. Specifications for research-grade material are often stated as 95 percent or higher, though the exact limit depends on the supplier and the intended use.
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.
The activity of this peptide is generally described as immunomodulatory rather than directly antimicrobial. Experimental work links it to signaling through certain Toll-like receptors on dendritic cells and to downstream maturation of antigen-presenting cells. Reported effects include expansion of T cell subsets, shifts in cytokine profiles, and increased natural killer cell activity. These observations come largely from cell culture and animal models, and the precise receptor-level events in humans remain incompletely characterized.
The compound has been investigated as an adjunct in chronic viral hepatitis and as a vaccine adjuvant, with results that vary by study design and population. Regulators in some countries have approved a synthetic form for specific indications, while other agencies have not. Whether the peptide produces consistent clinical benefit across diverse patient groups is still an open question, and many trials have been small. Its status is therefore best described as investigational in many contexts and established only narrowly.
This increase in system Xc- activity leads to an increase in extrasynaptic glutamate, causing stimulation of Group 2 mGluRs and an inhibition of synaptic release of glutamate. Cysteine prodrugs also lead to an increase in antioxidant properties by increasing levels of glutathione. Increased levels of glutathione lead to a lower toxicity of methamphetamine and alcohol, and cause a decrease in tumor formation after chronic smoking. N-acetylcysteine has been shown to decrease cravings and use of cocaine and tobacco, as well as other compulsive behaviors such as gambling and trichotillomania. Repeated administration of cocaine causes disruptions in glutamate homeostasis that lead to a decrease in function of EAATs. It is also possible that glutamate is diffusing from surrounding synapses and is stimulating extrasynaptic receptors. All of these factors may be leading to the disruptions in glutamate signaling that are associated with drug addiction.
It was speculations about isotopy that directly gave rise to the building of a mass spectrometer capable of separating the isotopes of the chemical elements. Aston initially worked on the identification of isotopes in the element neon and later chlorine and mercury. In 1912, Aston discovered that the neon splits into two tracts, roughly corresponding to atomic mass 20 and 22. He named the mass 22 one "meta-neon", a name he took from Occult Chemistry. First World War stalled and delayed his research on providing experimental proof for the existence of isotopes by mass spectroscopy and during the war, Aston worked at the Royal Aircraft Establishment in Farnborough as a Technical Assistant working on aeronautical coatings. After the war, he returned to research at the Cavendish Laboratory in Cambridge and completed building his first mass spectrograph that he reported on in 1919. Subsequent improvements in the instrument led to the development of a second and third instrument of improved mass resolving power and mass accuracy. These instruments employing electromagnetic focusing allowed him to identify 212 naturally occurring isotopes. In 1921, Aston became a member of the International Committee on Atomic Weights and a fellow of the Royal Society and received the Nobel Prize in Chemistry the following year.
== Treatment and prognosis == The recommended treatment for individuals presenting with localized MFS tumors is radical surgical resection. The resection should include a 2 cm margin of soft tissue surrounding the tumor, with planned resection of the entire area as defined by MRI-detected increased signals on T2-weighted images. This is done to ensure that all tumor tissue is removed in order to avoid the high risks of local recurrences and worsening prognoses. Historically, about 10% of patients treated with radical surgery developed recurrences at the surgical site and a significant number of these patients developed metastatic disease. Consequently, adjuvant radiotherapy has been used to help reduce these recurrences and metastatic transformations. For patients with a limb tumor that cannot be resected (less than 5% of all cases)), limb amputation is the treatment of choice. Recurrent and metastatic MFS first-line treatment has employed two chemotherapy drugs, anthracycline and Ifosfamide, while second-line treatment has employed two other chemotherapy drugs, gemcitabine and paclitaxel. Triple chemotherapy drug treatment (adriamycin, ifosfamide, and dacarbazine) has also been used to treat MFS. However, there are no randomized clinical trials evaluating the efficacy of these or other chemotherapy drugs in the treatment of inoperable or metastatic MFS and none of the uncontrolled studies have demonstrated a benefit in improving the overall survival in MFS.
Sources: en.wikipedia.org
A 2017 film adaptation of Wonder, starring Julia Roberts, Owen Wilson and Jacob Tremblay, was released in November 2017. A stage adaption premiered in 2025, with actor Garrett McNally, who has Treacher Collins syndrome himself, portraying the character in certain shows. Alison Midstokke, who appears in the drama film Happy Face (2018), is an actress and activist who has the condition.
"I am Shutruk-Nahhunte, son of Hallutush-Inshushinak, beloved servant of the god Inshushinak, king of Anshan and Susa, who has enlarged the kingdom, who takes care of the lands of Elam, the lord of the land of Elam. When the god Inshusinak gave me the order, I defeated Sippar. I took the stele of Naram-Sin and carried it off, bringing it to the land of Elam. For Inshushinak, my god, I set it as an offering."
The first two bus operating contracts for the new Weaver Network were awarded in September 2026 to FirstGroup, covering Huddersfield and parts of Leeds, and Transdev Blazefield, covering Dewsbury. In October 2021, £830 million of funding was announced for the West Yorkshire Combined Authority through the City Region Sustainable Transport Settlement, including funding to develop mass transit proposals for the region. Consultation was undertaken between July and September 2024 on proposed tram routes linking Bradford and Leeds, and St. James Hospital, central Leeds and White Rose Shopping Centre. Following a review by the National Infrastructure and Service Transformation Authority, the programme was moved to a more sequential approach intended to reduce delivery risk, contributing to a delay in the expected timetable for the scheme.
Sources: en.wikipedia.org
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio. These spectra are used to determine the elemental or isotopic signature of a sample, the masses of particles and of molecules, and to elucidate the chemical identity or structure of molecules and other chemical compounds. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures.
"Europeans who visited the area during this period related that the Druze "love the Christians more than the other believers", and that they "hate the Turks, the Muslims and the Arabs [Bedouin] with an intense hatred". Conversely, the relationship between the Druze and Muslims has been characterized by intense persecution. Meanwhile, interactions between Jews and Druze were rare before the establishment of Israel in 1948, as they historically lived isolated from each other.
Activation: Ubiquitin is activated in a two-step reaction by an E1 ubiquitin-activating enzyme, which is dependent on ATP. The initial step involves production of a ubiquitin-adenylate intermediate. The E1 binds both ATP and ubiquitin and catalyses the acyl-adenylation of the C-terminus of the ubiquitin molecule. The second step transfers ubiquitin to an active site cysteine residue, with release of AMP. This step results in a thioester linkage between the C-terminal carboxyl group of ubiquitin and the E1 cysteine sulfhydryl group. The human genome contains two genes that produce enzymes capable of activating ubiquitin: UBA1 and UBA6. Conjugation: E2 ubiquitin-conjugating enzymes catalyse the transfer of ubiquitin from E1 to the active site cysteine of the E2 via a trans(thio)esterification reaction. In order to perform this reaction, the E2 binds to both activated ubiquitin and the E1 enzyme. Humans possess 35 different E2 enzymes, whereas other eukaryotic organisms have between 16 and 35. They are characterised by their highly conserved structure, known as the ubiquitin-conjugating catalytic (UBC) fold. Ligation: E3 ubiquitin ligases catalyse the final step of the ubiquitylation cascade. Most commonly, they create an isopeptide bond between a lysine of the target protein and the C-terminal glycine of ubiquitin. In general, this step requires the activity of one of the hundreds of E3s. E3 enzymes function as the substrate recognition modules of the system and are capable of interaction with both E2 and substrate. Some E3 enzymes also activate the E2 enzymes.
The Seven Years' War (1756–1763) was fought across all of North America, Europe, Asia, Africa, and South America. Most of the great powers of the era participated, notably including the British Empire and French Empire, but polities from many continents played important roles. As a result, some historians describe it as the first global conflict, or as a world war. Historians like Richard F. Hamilton and Holger H. Herwig created a list of eight world wars, including the two generally agreed-upon world wars, the Seven Years' War, and five others: the Nine Years' War (1689–1697), the War of the Spanish Succession (1701–1714), the War of the Austrian Succession (1740–1748), the French Revolutionary Wars (1792–1802), and the Napoleonic Wars (1803–1815). British historian John Robert Seeley dubbed all of those wars between France and Great Britain (later the UK) between 1689 and 1815 (including the American Revolutionary War from 1775 to 1783) as the Second Hundred Years' War, echoing an earlier period of conflict between France and England known as the Hundred Years' War (1337–1453). Some writers have referred to the American Revolutionary War alone as a world war. Others (like William R. Thompson or Chase-Dunn and Sokolovsky) also include the Italian Wars and Dutch wars (Dutch-Spanish and Anglo-Dutch Wars) as part of Global Wars, while classifying WW1 and WW2 as the Global German Wars, and the Coalition Wars with Wars of Louis XIV as the 2nd and 1st Global French Wars.
Sources: en.wikipedia.org
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.
The name traces back to thymosin fraction 5, a crude thymus extract examined in the 1970s. Individual peptides in that mixture were labeled with Greek letters, and alpha-1 was one of them. The international nonproprietary name thymalfasin was assigned later.
No. Thymosin beta-4 contains 43 residues and binds actin, while thymosin alpha-1 contains 28 residues and acts on immune cells. The two sit in a historical naming group but share no sequence similarity, and they are not substitutes for one another.
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.