The short version of counter-ion fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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。
Several factors accelerate degradation: alkaline pH, elevated temperature, exposure to oxidants, and the presence of residual moisture. Deamidation of asparagine residues and oxidation of methionine are the most commonly reported degradation routes. Because the peptide lacks disulfide bonds, it does not undergo the thiol-related aggregation seen in some other biologics, but physical aggregation can still occur at high concentration. Stability data are product-specific, and extrapolating shelf life between formulations is not reliable.
Lyophilized thymosin alpha-1 is generally stored at or below minus twenty degrees Celsius, protected from moisture and light. Short-term handling at ambient temperature is possible for dry powder, but reconstituted solutions degrade faster and are usually kept at two to eight degrees Celsius with a defined expiry of days rather than weeks. Repeated freeze-thaw cycles should be avoided because they promote aggregation and loss of potency. Exact limits depend on the formulation and should follow the supplier's documentation.
| Property | Value | Notes |
|---|---|---|
| 化学分类 | 线性肽 | 由28个氨基酸组成 |
| 分子量 | 约3108 Da | 合成版本一致 |
| 外观 | 白色至类白色粉末 | 冻干品 |
| 溶解度 | 易溶于水 | 微溶于有机溶剂 |
| 储存温度 | -20°C（冻干） | 溶解后2-8°C |
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.
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.
Laboratory supplies of the peptide usually arrive as a lyophilized powder in sealed vials. The powder is hygroscopic, so a vial should be allowed to reach room temperature before it is opened to prevent condensation on the contents. Weighing and transfer are best performed in a low-humidity environment with clean tools. Once dissolved, the solution should be mixed gently rather than vortexed, because foaming and shear can reduce recovery of the peptide.
=== Screening === Cardiovascular system screening is considered mandatory by the EASL, as MASLD outcomes often result in cardiovascular complications, which can manifest as subclinical atherosclerosis, the cause of most MASLD-related deaths. People with MASLD are at high risk for cardiovascular morbidity and mortality, and "aggressive modification of cardiovascular disease risk factors is warranted in all patients" according to AASLD. The AASLD further recommends that people with a cirrhotic MASH be systematically screened for gastric and esophageal varices and liver cancer. They do not recommend routine liver biopsies and screening for liver cancer for non-cirrhotic people with MASH, but such screening sometimes occurs on a case-by-case basis. Also, people with MASLD may be considered for screening for hepatocellular carcinoma (liver cancer) and gastroesophageal varices. The NICE advises regular screening of people with MASLD for advanced liver fibrosis every three years for adults and every two years for children using the enhanced liver fibrosis (ELF) blood test. Follow-up is recommended for people with obesity and insulin resistance using the homeostasis model assessment of insulin resistance (HOMA-IR). People with MASH with fibrosis and hypertension merit closer monitoring, as there is a higher risk of disease progression.
=== Other methods in molecular vibrational spectroscopy === Infrared spectroscopy is not the only method of studying molecular vibrational spectra. Raman spectroscopy involves an inelastic scattering process in which only part of the energy of an incident photon is absorbed by the molecule, and the remaining part is scattered and detected. The energy difference corresponds to absorbed vibrational energy. The selection rules for infrared and for Raman spectroscopy are different at least for some molecular symmetries, so that the two methods are complementary in that they observe vibrations of different symmetries. Another method is electron energy loss spectroscopy (EELS), in which the energy absorbed is provided by an inelastically scattered electron rather than a photon. This method is useful for studying vibrations of molecules adsorbed on a solid surface. high-resolution EELS (HREELS) is a technique for performing vibrational spectroscopy in a transmission electron microscope (TEM). In combination with the high spatial resolution of the TEM, unprecedented experiments have been performed, such as nano-scale temperature measurements, mapping of isotopically labeled molecules, mapping of phonon modes in position- and momentum-space, vibrational surface and bulk mode mapping on nanocubes, and investigations of polariton modes in van der Waals crystals. Analysis of vibrational modes that are IR-inactive but appear in inelastic neutron scattering is also possible at high spatial resolution using EELS.
=== Compilation appearances === 2013: Women Who Kill (Tracks 1–3) (Entertainment One) – DVD/download/streaming 2015: Comedy Central Stand-Up Vault# 3 (Comedy Central) – DVD 2018: Just for Laughs: The Nasty Show, Vol. 1 (Tracks 1–2) – CD/download/streaming 2018: Just for Laughs: The Nasty Show, Vol. 2 (Tracks 1–3) – CD/download/streaming 2019: Just for Laughs: Funny AF, Vol. 1 (Track 1) – CD/download/streaming 2019: Just for Laughs: Funny AF, Vol. 2 (Tracks 1–3) – CD/download/streaming 2019: Just for Laughs: Funny AF, Vol. 3 (Track 1) – CD/download/streaming
=== Substrates === Norepinephrine Substrate-type norepinephrine releasing agents (e.g., ephedrine, amphetamine) Catecholaminergic activity enhancers (e.g., selegiline, PPAP, BPAP) Certain noradrenergic neurotoxins (e.g., DSP-4, xylamine)
=== Charge-exchange chemical ionization === This is also similar to CI and the difference lies in the production of a radical cation with an odd number of electrons. The reagent gas molecules are bombarded with high energy electrons and the product reagent gas ions abstract electrons from the analyte to form radical cations. The common reagent gases used for this technique are toluene, benzene, NO, Xe, Ar and He. Careful control over the selection of reagent gases and the consideration toward the difference between the resonance energy of the reagent gas radical cation and the ionization energy of the analyte can be used to control fragmentation. The reactions for charge-exchange chemical ionization are as follows.
Sources: en.wikipedia.org
=== Variability in phenotype and modifying genes === Some affected animals may remain subclinical, others may have mild signs that do not impede athletic performance, while some horses will have clinical signs that prevent any forced exercise. Rarely, horses will die from acute episodes of rhabdomyolysis. The reason for such variability of phenotype is not fully understood. Temperament, sex, and body type have no effect on degree of clinical signs. However, environmental factors such as diet and exercise, whether the horse is heterozygous or homozygous for the mutated GSY1 allele, and the presence of modifying genes all play a role. Additionally, some affected horses may have PSSM Type 2, which will produce different cellular changes and subsequently different phenotypic effects. One such modifying genes is RYR1, which is responsible for calcium regulation in muscle cells. RYR1 mutation causes malignant hyperthermia, a rare but potentially fatal disorder usually associated with anesthesia. While RYR1 mutation is rare in horses, including the general Quarter Horse population, it is much more common in Quarter Horses with GSY1 mutation. Horses with both mutations are more likely to have a severe PSSM phenotype, including higher levels of blood creatine kinase (CK), more severe exercise intolerance, more severe episodes of rhabdomyolysis (more frequent muscle fasciculations, more frequent episodes that are not associated with exercise, acute death), and poor response to PSSM treatment.
If references are made, the Court of Justice will give a preliminary ruling, in order for the member state court to conclude the case and award a remedy. The right to an effective remedy is a general principle of EU law, enshrined in the Charter of Fundamental Rights article 47. Most of the time Regulations and Directives will set out the relevant remedies to be awarded, or they will be construed from the legislation according to the practices of the member state. It could also be that the government is responsible for failure to properly implement a Directive or Regulation, and must therefore pay damages. In Francovich v Italy, the Italian government had failed to set up an insurance fund for employees to claim unpaid wages if their employers had gone insolvent, as the Insolvency Protection Directive required. Francovich, the former employee of a bankrupt Venetian firm, was therefore allowed to claim 6 million Lira from the Italian government in damages for his loss. The Court of Justice held that if a Directive would confer identifiable rights on individuals, and there is a causal link between a member state's violation of EU and a claimant's loss, damages must be paid. The fact that the incompatible law is an Act of Parliament is no defence. So, in Factortame it was irrelevant that Parliament had legislated to require a quota of British ownership of fishing vessels in primary legislation.
A tumor is classified as either benign or malignant based on its invasive potential. Benign tumors are non-invasive: They cannot invade adjacent tissues or metastasize (spread via metastasis). In contrast, malignant tumors are invasive or metastatic. For this reason, benign tumors are not classed as cancer. A benign tumor will grow in a contained area, usually a fibrous connective tissue capsule. The growth rates of benign and malignant tumors usually differ, with benign tumors growing more slowly than malignant tumors. However, cases of fast-growing benign tumors have been documented. Although benign tumors generally pose a lower health risk than malignant tumors, both can be life-threatening. Benign and malignant tumors differ in some general characteristics, but sometimes a benign tumor will exhibit some characteristics of a malignant tumor, or vice versa. For example, benign tumors are mostly well-differentiated, and malignant tumors are often undifferentiated. However, undifferentiated benign tumors can occur, as can differentiated malignant tumors. Certain malignant tumors, such as basal-cell carcinomas, are mostly non-metastatic.
=== Recovery === Before initiating any form of physical activity, the individual must demonstrate a normal level of functioning with all previous symptoms absent. Physical activity should be supervised by a health care professional in case of a recurrence. However, in some low-risk individuals, supervision by a medical professional is not required as long as the individual follows up with weekly checkups. Proper hydration prior to performing physical activity and performing exercise in cool, dry environments may reduce the chances of developing a reoccurring episode of ER. Lastly, it is imperative for urine and blood values to be monitored along with careful observation for the redevelopment of any signs or symptoms. The recovery program focuses on progressive conditioning/reconditioning the individual and improving functional mobility. However, special considerations prior to participating in the rehabilitation program include the individual's 1) extent of muscle injury, if any 2) level of fitness before the incident and 3) weight training experience. These special considerations collectively are a form of assessing the individual's capacity to perform physical activity, which is ultimately used to specify the ExRx design.
Sources: en.wikipedia.org
== Clinical significance == G6PD is remarkable for its genetic diversity. Many variants of G6PD, mostly produced from missense mutations, have been described with wide-ranging levels of enzyme activity and associated clinical symptoms. Two transcript variants encoding different isoforms have been found for this gene. Glucose-6-phosphate dehydrogenase deficiency is very common worldwide, and causes acute hemolytic anemia in the presence of simple infection, ingestion of fava beans, or reaction with certain medicines, antibiotics, antipyretics, and antimalarials.
Isoaspartic acid (isoaspartate, isoaspartyl, β-aspartate) is an aspartic acid residue isomeric to the typical α peptide linkage. It is a β-amino acid, with the side chain carboxyl moved to the backbone. Such a change is caused by a chemical reaction in which the nitrogen atom on the N+1 following peptide bond (in black at top right of Figure 1) nucleophilically attacks the γ-carbon of the side chain of an asparagine or aspartic acid residue, forming a succinimide intermediate (in red). Hydrolysis of the intermediate results in two products, either aspartic acid (in black at left) or isoaspartic acid, which is a β-amino acid (in green at bottom right). The reaction also results in the deamidation of the asparagine residue. Racemization may occur leading to the formation of D-aminoacids.
On February 25, 2007, the Commonwealth of Virginia resolved to 'profoundly regret' and apologize for its role in the institution of slavery. Unique and the first of its kind in the U.S., the apology was unanimously passed in both Houses as Virginia approached the 400th anniversary of the founding of Jamestown. On August 24, 2007, Mayor of London Ken Livingstone issued a public apology for London's role in Atlantic slave trade, which took place at an event commemorating the 200th anniversary of the British slave trade's abolition. In his speech, Livingstone described the slave trade as "the racial murder of not just those who were transported but generations of enslaved African men, women and children. To justify this murder and torture black people had to be declared inferior or not human... We live with the consequences today." City officials in Liverpool, which was a large slave trading port, apologized in 1999. On July 30, 2008, the United States House of Representatives passed a resolution apologizing for American slavery and subsequent discriminatory laws. In June 2009, the U.S. Senate passed a resolution apologizing to African-Americans for the "fundamental injustice, cruelty, brutality, and inhumanity of slavery". The news was welcomed by President Barack Obama, the nation's first president of African descent. Some of President Obama's ancestors may have been slave owners. In 2010, Libyan leader Muammar Gaddafi apologized for Arab involvement in the slave trade, saying: "I regret the behavior of the Arabs...
== Homicides == Thailand ranked 30 of 216 countries for its number of homicides (2,387) in 2015. Other ASEAN nations ranked: Philippines, 14 (9,756 homicides); Vietnam, 39 (1,358); Myanmar, 41 (1,304); Indonesia, 42 (1,277); Malaysia, 74 (540); Laos, 79 (467); Cambodia, 100 (268); Singapore, 175 (14); Brunei, 197 (2). Among ASEAN nations, the Philippines had the highest rate of homicides per 100,000 population (9.84), followed by Laos (6.87), and Thailand (3.51). Singapore had the lowest homicide rate in ASEAN, with just 0.25 murders per 100,000 population.
=== History === Emus were first reported as having been seen by Europeans when explorers visited the western coast of Australia in 1696. This was during an expedition led by Dutch captain Willem de Vlamingh who was searching for survivors of a ship that had gone missing two years earlier. The birds were known on the eastern coast before 1788, when the first Europeans settled there. The birds were first mentioned under the name of the "New Holland cassowary" in Arthur Phillip's Voyage to Botany Bay, published in 1789 with the following description:
Sources: en.wikipedia.org
它不是经典的内分泌激素，而是一种免疫调节肽。其作用主要通过局部免疫细胞间的信号传递实现，而非经血液循环作用于远隔器官。
天然胸腺素α1主要从胸腺组织提取，也可在脾脏和淋巴结中检出。目前研究和临床使用的多为化学合成版本，不再依赖动物组织。
胸腺素组分5是牛胸腺提取物的粗组分，包含多种肽。胸腺素α1是其中一种被纯化和表征的单一肽，具有明确的28个氨基酸序列。
Dry lyophilized powder tolerates short ambient exposure during handling and shipping. Long-term room-temperature storage is not recommended because moisture uptake and slow degradation can occur over months. Storage at minus twenty degrees Celsius is the common practice for extended periods.