If you have been reading about immune modulation 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 2026-07-23. Where a claim depends on a specific study, the study is described rather than over-claimed.
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。
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.
| 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 |
Laboratory work indicates that the peptide acts on cells of both the innate and adaptive immune systems. Reported effects include signalling through Toll-like receptors on dendritic cells, enhanced T-cell maturation, and increased natural killer cell activity. These actions are described largely from cell-culture and animal experiments, and the precise receptor-level events remain incompletely defined. Studies in humans have generally measured immune markers rather than a single defined molecular target. The resulting picture remains partly descriptive.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Results across trials have been mixed, and several studies were small or conducted under differing protocols. Regulatory status varies by country, and the compound is not approved in every jurisdiction where it is studied. Evidence for any single indication should be read with attention to sample size and endpoint choice.
Thymosin alpha-1 is a 28-residue peptide first isolated from thymus tissue in the 1970s. It corresponds to the N-terminal portion of thymosin beta-4, from which it is cleaved in vivo. The peptide carries an acetyl group at its N-terminus, a modification that affects its charge and stability. Synthetic material produced by solid-phase peptide synthesis is chemically identical to the natural fragment and is the form used in research and clinical 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.
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 Springboks had fulfilled all of their touring commitments through the Fifties and Sixties but the oppressive, claustrophobic political pressures overwhelmed them during the Seventies. They have not been able to play in Britain, Ireland, France or Australia since 1974, and their only major tour abroad in the last ten years to New Zealand in 1981, was full of controversy, and mass demonstrations. There is no doubt that giant steps have been taken to make Rugby totally integrated in South Africa in recent years, and their supporters feel that no sooner have they fulfilled the conditions required of them by world opinion than the goalposts are moved. Their opponents, who are against having any sporting links with a country which practises apartheid, accept that sport in South Africa has become increasingly integrated but claim it is impossible to have normal sport in an abnormal society.
Philip Zimbardo suggests we might also analyze happiness from a "time perspective". He suggested the sorting of people's focus in life by valence (positive or negative) and also by their time perspective (past, present, or future orientation). Doing so may reveal some individual conflicts, not over whether an activity is enjoyed, but whether one prefers to risk delaying gratification further. Zimbardo also believes research reveals an optimal balance of perspectives for a happy life; commenting, our focus on reliving positive aspects of our past should be high, followed by time spent believing in a positive future, and finally spending a moderate (but not excessive) amount of time in enjoyment of the present.
The chemical ecology of plant-insect interaction is a significant subfield of chemical ecology. In particular, plants and insects are often involved in a chemical evolutionary arms race. As plants develop chemical defenses to herbivory, insects which feed on them co-evolved to develop immunity to these poisons, and in some cases, repurpose these poisons for their own chemical defense against predators. For example, caterpillars of the monarch butterfly sequester cardenolide toxins from their milkweed host-plants and are able to use them as an anti-predator defense. Whereas most insects are killed by cardenolides, which are potent inhibitors of the Na+/K+-ATPase, monarchs have evolved resistance to the toxin over their long evolutionary history with milkweeds. Other examples of sequestration include the tobacco hornworm Manduca sexta, which use nicotine sequestered from tobacco plants in predator defense; and the bella moth, which secretes a quinone-containing froth to deter predators obtained from feeding on Crotalaria plants as a caterpillar. Chemical ecologists also study chemical interactions involved in indirect defenses of plants, such as the attraction of predators and parasitoids through herbivore-induced volatile organic compounds (VOCs).
Hypothermia, especially during winter months Metabolic disruption including hypoglycemia, hyponatremia, acidosis, and hypercalcemia Respiratory compromise including hypoxemia and hypercapnia Infections including pneumonia, cellulitis, and urosepsis Congestive heart failure Cerebrovascular accidents Gastrointestinal bleeding Trauma, motor vehicle accidents, and fractures Medications including anesthetics, sedatives, tranquilizers, narcotics, amiodarone, and lithium Withdrawal of thyroid supplements, especially in relation to a hospitalization Other precipitating factors include:
Hamdullah Fitrat, Taliban's deputy spokesperson, said the Pakistani forces targeted a home in Paktia's Chamkani district, killing an elder and a child, while injuring others. The area was struck again 25 minutes after the first strike when residents had gathered to rescue people. 28 villagers died in the second strike while 158 more were wounded. Hospital footage showed infants and elderly victims on stretchers. A survivor directly refuted Pakistan's claims that the targets were terrorists. Additionally, six more civilians were killed in a Giyan district village in Paktika province. Pakistani electronic jammers also downed a drone in North Waziristan. On 29 June, insurgents killed a police constable in Bannu District, while four TTP militants were also killed in an operation in the district. An explosion and fire were reported in Kabul. Six border guards were killed, nine wounded and one abducted as Pakistani Taliban militants overrun a border post in Chitral District. On 30 June, an Afghan Refugees Camp was hit in a drone strike/shootdown in Pishin District and a school was hit by a drone strike in Kila Abdullah District, Pakistan Air Force also downed a drone in Quetta. Pakistan claimed to have shot down a total of four "rudimentary" drones from Afghanistan. Afghanistan claimed that its forces successfully hit an ISKP camp in Pishin District. Border post No. 2417 in Kurram District was targeted by sniper fire killing one Pakistani FC soldier. On 1 July, an Afghan drone was shot down by Pakistani forces in Khyber District.
Sources: en.wikipedia.org
Among other things, the parathyroid hormone causes calcium and phosphate to be released from the bones, which ultimately leads to renal bone disorders and calcification of the kidneys, skin, heart and blood vessels. In the kidneys, this calcification contributes to further destruction of the kidney tissue. The reduced responsiveness of the parathyroid cells to calcium disrupts the negative feedback of parathyroid hormone secretion, so that parathyroid hormone continues to be secreted despite the increase in calcium levels. As less phosphate reaches the renal tubules due to the reduced filtration rate, the inhibitory effect of parathyroid hormone on reabsorption in the main body has only a minor effect on the blood phosphate level. The loss of nephrons and the associated decrease in the number of sodium ion channels leads to a decrease in the concentration gradient in the kidney. However, this is the driving force for water reabsorption in the mid-piece and—in the presence of ADH—also in the collecting ducts. The result is a loss of water via the urine and thus drying out of the body, which is exacerbated by the loss of fluid during vomiting. One consequence of the kidneys' reduced ability to excrete hydrogen ions, phosphate and sulphate and the excessive loss of bicarbonate is the metabolic acidification of the blood (metabolic acidosis). Metabolic acidosis occurs in 80% of cats with chronic kidney disease.
=== Pharmacokinetics === Buserelin is ineffective via oral administration due to first-pass metabolism in the gastrointestinal tract. Its bioavailability is 2.5 to 3.3% by intranasal administration and 70% by subcutaneous injection. The plasma protein binding of buserelin is approximately 15%. The metabolism of buserelin occurs in the liver, kidneys, and gastrointestinal tract and is mediated by peptidases, specifically pyroglutamyl peptidase and chymotrypsin-like endopeptidase. The elimination half-life of buserelin regardless of route of administration is about 72 to 80 minutes. Buserelin and its metabolites are eliminated in urine and bile, with approximately 50% of buserelin excreted in urine unchanged.
Above-ground nuclear tests by the Soviet Union and the United States in the 1950s and early 1960s and by France into the 1970s and 1980s spread a significant amount of fallout from uranium daughter isotopes around the world. Additional fallout and pollution occurred from several nuclear accidents. Uranium miners have a higher incidence of cancer. An excess risk of lung cancer among Navajo uranium miners, for example, has been documented and linked to their occupation. The Radiation Exposure Compensation Act, a 1990 law in the US, required $100,000 in "compassion payments" to uranium miners diagnosed with cancer or other respiratory ailments. During the Cold War between the Soviet Union and the United States, huge stockpiles of uranium were amassed and tens of thousands of nuclear weapons were created using enriched uranium and plutonium made from uranium. After the break-up of the Soviet Union in 1991, an estimated 600 short tons (540 metric tons) of highly enriched weapons grade uranium (enough to make 40,000 nuclear warheads) had been stored in often inadequately guarded facilities in the Russian Federation and several other former Soviet states. Police in Asia, Europe, and South America on at least 16 occasions from 1993 to 2005 have intercepted shipments of smuggled bomb-grade uranium or plutonium, most of which was from ex-Soviet sources. From 1993 to 2005 the Material Protection, Control, and Accounting Program, operated by the federal government of the United States, spent about US$550 million to help safeguard uranium and plutonium stockpiles in Russia.
=== Designed nucleic acid systems === Scientists can encode digital information onto a single strand of synthetic DNA. In 2012, George M. Church encoded one of his books about synthetic biology in DNA. The 5.3 Mb of data was more than 1000 times greater than the previous largest amount of information to be stored in synthesized DNA. A similar project encoded the complete sonnets of William Shakespeare in DNA. More generally, algorithms such as NUPACK, ViennaRNA, Ribosome Binding Site Calculator, Cello, and Non-Repetitive Parts Calculator enables the design of new genetic systems. Many technologies have been developed for incorporating unnatural nucleotides and amino acids into nucleic acids and proteins, both in vitro and in vivo. For example, in May 2014, researchers announced that they had successfully introduced two new artificial nucleotides into bacterial DNA. By including individual artificial nucleotides in the culture media, they were able to exchange the bacteria 24 times; they did not generate mRNA or proteins able to use the artificial nucleotides.
Sources: en.wikipedia.org
Erythritol (, US: ) is an organic compound, the naturally occurring achiral meso four-carbon sugar alcohol (or polyol). It is the reduced form of either D- or L-erythrose and one of the two reduced forms of erythrulose. It is used as a food additive and sugar substitute. It is synthesized from corn using enzymes and fermentation. Its formula is C4H10O4, or HO(CH2)(CHOH)2(CH2)OH. Erythritol is 60–70% as sweet as table sugar. However, erythritol is almost completely noncaloric and does not affect blood sugar or cause tooth decay. Japanese companies pioneered the commercial development of erythritol as a sweetener in the 1990s.
Neuropeptide FF group Neuropeptide AF Neuropeptide FF Neuropeptide SF (RFRP-1) Neuropeptide VF (RFRP-3) (GnIH - avian species) Prolactin-releasing peptide (PrRP) Pyroglutamylated RFamide peptide (QRFP) Kisspeptin (disputed)
=== Myeloid cells === The effects of TGF-β1 on macrophages and monocytes are predominantly suppressive; this cytokine can inhibit the proliferation of these cells and prevent their production of reactive oxygen (e.g. superoxide (O2−)) and nitrogen (e.g. nitric oxide (NO)) intermediates. However, as with other cell types, TGF-β1 can also have the opposite effect on cells of myeloid origin. For example, TGF-β1 acts as a chemoattractant, directing an immune response to certain pathogens. Likewise, macrophages and monocytes respond to low levels of TGF-β1 in a chemotactic manner. Furthermore, the expression of monocytic cytokines (such as interleukin(IL)-1α, IL-1β, and TNF-α), and macrophage's phagocytic can be increased by the action of TGF-β1. TGF-β1 reduces the efficacy of the MHC II in astrocytes and dendritic cells, which in turn decreases the activation of appropriate helper T cell populations.
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。
Its sequence corresponds to the amino-terminal portion of prothymosin alpha, a larger protein present in many cell types. The isolated 28-residue peptide is a fragment of that protein rather than a separately encoded molecule, and laboratory material is produced by synthesis.