If you have been reading about Thymalfasin 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 2025-10-28. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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 |
|---|---|---|
| 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.
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。
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.
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.
In other words, regardless of how severe a person's depression is at treatment initiation, the efficacy of venlafaxine remains consistent and is not influenced by the severity of depression at the start of treatment.
Lisdexamphetamine is an inactive prodrug that is converted in the body to dextroamphetamine, a pharmacologically active compound that is responsible for the drug's activity. After oral ingestion, lisdexamphetamine is broken down by enzymes in red blood cells to form L-lysine, a naturally occurring essential amino acid, and dextroamphetamine. The half-life of this conversion is roughly 1 hour. The conversion of lisdexamphetamine to dextroamphetamine is not affected by gastrointestinal pH and is unlikely to be affected by alterations in normal gastrointestinal transit times. Studies show a linear relationship between peak plasma concentration of dextroamphetamine and lisdexamphetamine dose up to lisdexamphetamine doses of 250 mg. The optical isomers of amphetamine, i.e., dextroamphetamine and levoamphetamine, are TAAR1 agonists and vesicular monoamine transporter 2 inhibitors that can enter monoamine neurons; this allows them to release monoamine neurotransmitters (dopamine, norepinephrine, and serotonin, among others) from their storage sites in the presynaptic neuron, as well as prevent the reuptake of these neurotransmitters from the synaptic cleft. Lisdexamphetamine was developed to provide a long-duration effect that is consistent throughout the day, with reduced potential for abuse. The attachment of the amino acid lysine slows down the relative amount of dextroamphetamine available in the bloodstream.
If this is the case, similarity in lifetimes of intermediate daughters becomes a meaningless argument, as different isomers of the same nuclide can have different half-lives: for example, the ground state of 180Ta has a half-life of hours, but an excited state 180mTa has never been observed to decay. This study found reason to doubt and criticise the IUPAC approval of the discoveries of elements 115 and 117, but the data from Riken for element 113 was found to be congruent, and the data from the JINR team for elements 115 and 113 to probably be so, thus endorsing the IUPAC approval of the discovery of element 113. Two members of the JINR team published a journal article rebutting these criticisms against the congruence of their data on elements 113, 115, and 117 in June 2017.
== Atrial fibrillation == Pulmonary vein isolation has been the mainstay of atrial fibrillation reduction, but in many cases there are other sources of arrhythmia, including the LoM. Use of ethanol through the VoM has been shown to be an effective way to reduce atrial fibrillation.
Sources: en.wikipedia.org
He explained the importance of O'Higgins and his horse walking over the corpse of a dead enemy tyrant's soldier. The Cuban Army General Staff Band played El Mambi and La Bayamesa. The delegation from the Dominican Republic reminded the room that Máximo Gómez had been born in their country, and had died in Cuba. After a prayer to the Great Architect of the Universe, the Conference conducted its normal business.
In France, students attending clinical practice are known as "externes" and newly qualified practitioners training in hospitals are known as "internes". The residency, called "Internat", lasts from three to six years (depending on the speciality) and follows a competitive national ranking examination. It is customary to delay submission of a thesis. As in most other European countries, many years of practice at a junior level may follow. French residents are often called "doctor" during their residency. Literally speaking, they are still students and become M.D. only at the end of their residency and after submitting and defending a thesis before a jury.
Baran began his independent career at the Scripps Research Institute in the summer of 2003, and received tenure just three years later. In the 20 years since then, he has supervised over 300 graduate students, post-doctoral scholars, visiting scholars and interns. He is currently the Dr. Richard A. Lerner Endowed Chair at Scripps Research
Currently, the standard treatment is autografting which involves obtaining the donor bone from a non-significant and easily accessible site (i.e. iliac crest) in the patient own body and transplanting it into the defective site. Transplantation of autologous bone has the best clinical outcome because it integrates reliably with the host bone and can avoid complications with the immune system. But its use is limited by its short supply and donor site morbidity associated with the harvest procedure. Furthermore, autografted bones are avascular and hence are dependent on diffusion for nutrients, which affects their viability in the host. The grafts can also be resorbed before osteogenesis is complete due to high remodeling rates in the body. Another strategy for treating severe bone damage is allografting which transplants bones harvested from a human cadaver. However, allografts introduce the risk of disease and infection in the host. Bone tissue engineering presents a versatile response to treat bone injuries and deformations. Nanofibers produced via electrospinning mimics the architecture and characteristics of natural extracellular matrix particularly well. These scaffolds can be used to deliver bioactive agents that promote tissue regeneration. These bioactive materials should ideally be osteoinductive, osteoconductive, and osseointegratable. Bone substitute materials intended to replace autologous or allogeneic bone consist of bioactive ceramics, bioactive glasses, and biological and synthetic polymers.
== Causes == Mutations in the COL11A1, COL11A2, and COL2A1 genes cause collagenopathy, types II and XI. These genes carry instructions for the protein strands that make up type II and type XI collagen. All collagen molecules are made of three protein strands (called alpha chains). The alpha chains may be identical or different, depending on the type of collagen. Type II collagen is made by combining three copies of the alpha chain made by the COL2A1 gene. Type XI collagen, on the other hand, is composed of three different alpha chains: the products of the COL2A1, COL11A1, and COL11A2 genes. Mutations in these genes interfere with the proper assembly of type II and XI collagens or reduce the amount of these collagens. Defective or reduced numbers of collagen molecules affect the development of bones and other connective tissues, causing the signs and symptoms of the type II and XI collagenopathies.
Sources: en.wikipedia.org
Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from Penicillium moulds, principally P. chrysogenum and P. rubens. Eight species of Penicillium, in the section Chrysogena, produce penicillins. Most penicillins in clinical use are synthesised by P. chrysogenum using deep tank fermentation and then purified. A number of natural penicillins have been discovered, but only two purified compounds are in clinical use: penicillin G (intramuscular or intravenous use) and penicillin V (given by mouth). Penicillins were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. They are still widely used today for various bacterial infections, though many types of bacteria have developed resistance following extensive use. In the United States, 10% of the population claims penicillin allergies, but because the frequency of positive skin test results decreases by 10% with each year of avoidance, 90% of these patients can eventually tolerate penicillin. Additionally, those with penicillin allergies can usually tolerate cephalosporins (another group of β-lactam) because the immunoglobulin E (IgE) cross-reactivity is only 3%. Penicillin was discovered in 1928 by the Scottish physician Alexander Fleming as a crude extract of P. rubens. Fleming's student Cecil George Paine was the first to successfully use penicillin to treat eye infection (neonatal conjunctivitis) in 1930.
The territory was subsequently claimed and settled by Portugal, which founded the country's first city, São Vicente, in 1532 and imported enslaved Africans to work on plantations. Brazil remained a colony until 1815, when it was elevated to a united kingdom with Portugal after the transfer of the Portuguese court to Rio de Janeiro. Prince Pedro of Braganza declared Brazilian independence in 1822 and, after waging a war against Portugal, established the Empire of Brazil. The country's first constitution in 1824 established a bicameral legislature and enshrined principles such as freedom of religion and the press; slavery was gradually abolished until its final abolition in 1888. Brazil became a presidential republic following a military coup d'état in 1889. An armed revolution in 1930 ended the First Republic and brought Getúlio Vargas to power. Vargas' self-coup in 1937 ushered the authoritarian Estado Novo, in which he oversaw Brazil's involvement in World War II. Democracy was restored after Vargas' ousting in 1945. An authoritarian military dictatorship emerged in 1964 with support from the United States and ruled until 1985, after which civilian governance resumed. Brazil's current constitution, enacted in 1988, defines it as a democratic federal republic. Brazil is a regional and middle power, and has been described as a rising global power.
The endocrine glands belong to the body's control system. The hormones which they produce help to regulate the functions of cells and tissues throughout the body. Endocrine organs are activated to release their hormones by humoral, neural, or hormonal stimuli. Negative feedback is important in regulating hormone levels in the blood. The nervous system, acting through hypothalamic controls, can in certain cases override or modulate hormonal effects.
== Nutrition == Some vitamins and other trace nutrients are lost, particularly from vegetables, partially by enzyme action during cooking and partially due to heat degradation. When vegetables are cooked at higher temperatures these enzymes are rapidly denatured and have less time to act during cooking. Since slow cookers work at temperatures well below boiling point and do not rapidly denature enzymes, vegetables tend to lose trace nutrients. Blanched vegetables, having been exposed to very hot water, have already had these enzymes rendered largely ineffective, so a blanching or sauteing pre-cook stage leaves more vitamins intact. This is often a smaller nutrient loss than over-boiling and can be lessened to an extent by not removing the lid until the food is done. Slow cookers should not be used to cook dried kidney beans and other legume seeds. These foods contain a highly toxic lectin, phytohemagglutinin, making as few as four raw beans toxic. This lectin is only deactivated by long soaking, then boiling in fresh water at 100 °C (212 °F) for at least thirty minutes. Information published by the United States Food and Drug Administration states that slow cookers should not be used to cook bean containing dishes. Commercially canned beans are fully cooked and are safe to use. Pressure cooking also deactivates the lectins.
== Biosynthesis == Early biosynthesis studies in Cetraria islandica showed that protolichesterinic acid is produced in very small quantities (approximately 0.1%) in the whole lichen. The compound is formed through the condensation of a fatty acid derivative with a C3 or C4 fragment derived from pyruvate or related precursors in the glycolytic pathway. Sixteen of its carbon atoms come from head-to-tail linkage of acetate units. The compound is not produced by isolated mycobionts in submerged culture, suggesting that the symbiotic relationship between fungi and algae may be important for its biosynthesis. The production appears to be influenced by aeration conditions. Further studies using radiolabeled precursors revealed seasonal variation in protolichesterinic acid biosynthesis in C. islandica. When [1-14C]acetate and [1,4-14C2]succinic acid were administered to the whole lichen in a glucose solution during summer months, both precursors were incorporated into protolichesterinic acid, supporting the hypothesis that aliphatic lichen acids have common precursors related to the citric acid and fatty acid cycles. However, during winter months, the lichen showed no incorporation of these precursors, indicating that biosynthesis becomes inactive during this season. The extremely low levels of incorporation (approximately 0.004%) suggested that protolichesterinic acid biosynthesis represents a very minor metabolic pathway in C. islandica.
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.