A practical reference on 合成肽: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-05-03. Anything still debated is marked as such rather than presented as settled.
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.
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.
Within the immune system, the peptide acts on several cell types rather than a single target. Reported activities include promotion of T-cell maturation, enhancement of natural killer cell activity, and modulation of cytokine production by dendritic cells and macrophages. Some of these effects appear to operate through toll-like receptor signaling, though the precise receptor-level mechanism remains debated. Whether the observed immune changes translate into clinical benefit is a separate question and depends on the indication studied.
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.
| 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 |
Immunological studies connect the peptide to multiple parts of the immune response. It has been reported to engage Toll-like receptor signaling, to promote dendritic cell maturation, and to influence the balance of T helper cell subsets. Changes in natural killer cell activity and in cytokine release appear in cell culture and animal models. These observations describe broad immunomodulatory behavior rather than a single defined receptor target, and the primary molecular interaction has not been settled.
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.
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。
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Findings across trials are mixed; some report changes in selected immune markers, while others find no clear clinical benefit. Many studies are small and define outcomes differently, which limits comparison. Regulatory approval is confined to a few countries, and the compound is not an approved drug in the United States or most of Europe.
Overall evidence quality varies considerably. A large share of published reports come from single centers, rely on surrogate immunological markers, or lack adequate control groups. Systematic reviews have highlighted this heterogeneity as a barrier to pooling results. Open questions include which patients, if any, might benefit, what treatment duration is appropriate, and whether any effect is independent of standard care. The peptide is often described as an immune modulator rather than a therapy for one disease, which complicates confirmatory trial design.
Thymosin alpha 1 was identified in 1977 as a component of thymosin fraction 5, a heterogeneous preparation used in early studies of thymic function. Investigators purified the active material and determined its amino acid sequence, which enabled chemical synthesis. Work in the following decades concentrated on T-cell maturation and immune reconstitution in animals and small human cohorts. Early preparations varied in composition, so results from that period are difficult to compare with studies using defined synthetic peptide.
Subcutaneous injection of racemic synephrine into rabbits was reported to cause a large rise in blood sugar. In experiments on anesthetized cats, Papp and Szekeres found that synephrine (stereochemistry unspecified) raised the thresholds for auricular and ventricular fibrillation, an indication of anti-arrhythmic properties. Evidence that synephrine might have some central effects comes from the research of Song and co-workers, who studied the effects of synephrine in mouse models of anti-depressant activity. These researchers observed that oral doses of 0.3 – 10 mg/kg of racemic synephrine were effective in shortening the duration of immobility produced in the assays, but did not cause any changes in spontaneous motor activity in separate tests. This characteristic immobility could be counteracted by the pre-administration of prazosin. Subsequent experiments using the individual enanatiomers of synephrine revealed that although the d-isomer significantly reduced the duration of immobility in the tail suspension test, at an oral dose of 3 mg/kg, the l-isomer had no effect at the same dose. In mice pre-treated with reserpine, an oral dose of 0.3 mg/kg d-synephrine significantly reversed the hypothermia, while l-synephrine required a dose of 1 mg/kg to be effective. Experiments with slices of cerebral cortex taken from rat brain showed that d-synephrine inhibited the uptake of [3H]-norepinephrine with an IC50 = 5.8 μM; l-synephrine was less potent (IC50 = 13.5 μM).
The degrees of Freemasonry in Cuba are overseen by two bodies; the Grand Lodge oversees the first three degrees of the Blue Lodge, while the Supreme Council oversees the higher 4th through the 33rd degrees. Master Masons are made at the fourth Degree. The Grand Master of Cuba oversees the Grand Lodge, while the Sovereign Grand Commander of Cuba oversees the Supreme Council. The Daughters of Acacia are overseen by the Great Gentle Mother of the Daughters of Acacia. The National Masonic Retirement Home is overseen by a Board of Trustees. The government of this institution is bicameral and parliamentary; with an institution called the Upper House of the Grand Lodge and another High Chamber of the Supreme Council that coordinate to draft Cuban Masonic Law. Presiding over the judicial system of that Masonic Law is the Supreme Court of Masonic Justice that decides cases. The Supreme Court of Masonic Justice is subdivided into Chambers, including the First Chamber of the Supreme Court and the Second Chamber of the Supreme Court, which are overseen by magistrates and a President of the Chamber. For cases that involve the government of Cuba outside of Masonic Law, the Grand Lodge and Supreme Council report to the Office of Religious Affairs (OAR) of the Communist Party of Cuba. The Grand Lodge and Supreme Council are also registered entities on the Registry of Associations, which is overseen by the Office of Associations at the Ministry of Justice.
=== Oak Park River Forest High School Outbreak === After 17 new cases were diagnosed in one week, the Oak Park Health Department forced Oak Park River Forest High School to cancel all extracurricular activities on December 3, 2021 and hinted toward a future move to suspend in-person learning. Oak Park Public Health Director Dr. Theresa Chapple expressed concerns that "only about 100 to 200 students" were tested each week which left the department blind to the actual size of the outbreak. SHIELD Illinois was engaged by the district on Saturday, December 4 about the possibility of testing the entire school population in one day. SHIELD rallied every employee trained to collect specimens, including executive leadership, accounting specialists, and logistics team members. Monday, December 6, 2021, SHIELD Illinois collected specimens from 1,651 students, faculty, and staff. This initial round of testing identified 20 positive patients. The health department allowed extracurricular activities to resume on December 7, 2021. SHIELD Illinois repeated the same process on December 9. This time testing 1,396 faculty, staff, and students--identifying an additional 3 positive cases.
== External links == WHO fact sheet on opioid overdose Community management of opioid overdose (PDF). World Health Organization. 2014. ISBN 978-92-4-154881-6. Archived from the original (PDF) on 1 September 2022.
Sources: en.wikipedia.org
Informed consent approaches include conversations between the medical provider and person seeking care on the details of risks and outcomes, current understandings of scientific research, and how the provider can best assist the person in making decisions. Local standards of care exist in many countries, with most local standards being based on the WPATH standards, with some minor exceptions.
=== Library of the School of Medicine === The School of Medicine at the University of Patras have an independent library to be used from the student's community of the School. The library provides a reading room (150 seats), a copy machine with charge of use and computers. Users may also borrow books from the library as long as they have the library card.
=== Miscellaneous applications === Molecular carpet/paint peptides can be used in diverse industries. They can be used as 'nano-organizers' for non-biological materials, or could be used to study cell-cell communications and behavior. It has also been found that the catalytic abilities of the lipase enzyme is greatly improved when encapsulated in a peptide nanotube. After incubation in a nanotube for a week, the catalytic activities of the enzyme is improved by 33%, compared with free-standing lipases at room temperature; at 65 °C the improvement rises to 70%. It is suggested that the enhanced ability is due to a conformational change to an enzymatically active structure.
In most of Central and Eastern Europe, poppy seed is commonly used for traditional pastries and cakes, and it is legal to grow poppies throughout the region, although Germany requires a license. Since January 1999 in the Czech Republic, according to the 167/1998 Sb. Addictive Substances Act, poppies growing in fields larger than 100 square metres (120 sq yd) is obliged for reporting to the local Custom Office. Extraction of opium from the plants is prohibited by law (§ 15 letter d/ of the act). It is also prohibited to grow varieties with more than 0.8% of morphine in dry matter of their capsules, excluding research and experimental purposes (§24/1b/ of the act). The name Czech blue poppy refers to blue poppy seeds used for food. The United Kingdom does not require a license for opium poppy cultivation, but does for extracting opium for medicinal products. When the European Union attempted to ban the cultivation of Papaver somniferum by private individuals on a small scale (such as personal gardens), citizens in EU countries where poppy seed is eaten heavily, such as countries in the Central-Eastern region, strongly resisted the plan, causing the EU to change course.
Kubitschek's successor, Jânio Quadros, resigned in 1961 less than a year after taking office. His vice-president, João Goulart, assumed the presidency, but aroused strong political opposition and was deposed in April 1964 by a coup that resulted in a military dictatorship.
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 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.