The short version of Thymalfasin fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-04-01. 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.
Lyophilized thymosin alpha 1 is typically stored refrigerated at 2 to 8 degrees Celsius and kept away from light. Reconstituted solutions are less stable and are usually used promptly after preparation. Repeated freeze-thaw cycles are avoided because they can promote aggregation and loss of activity. The peptide adsorbs to some plastic and glass surfaces, so a carrier protein is often added to dilute working solutions. Manufacturer instructions and published protocols both govern handling.
Identity and purity testing for thymosin alpha 1 relies mainly on reversed-phase high-performance liquid chromatography and mass spectrometry. Chromatography separates the parent peptide from truncated or modified variants, while mass spectrometry confirms the expected molecular mass. Amino acid analysis and peptide mapping provide additional sequence confirmation. Counterion content, water content, and residual solvents are measured separately as part of specification testing. No single method captures every attribute, so laboratories combine several techniques.
| 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 |
Thymosin alpha 1 is a short peptide of 28 amino acid residues that derives from the amino terminal region of a larger precursor protein known as prothymosin alpha. The peptide carries an acetyl group on its first residue and contains no disulfide bonds or carbohydrate chains. Its sequence is highly conserved across mammalian species, which is one reason laboratories treat it as a molecule with a defined and reproducible structure rather than a variable tissue extract. The name follows an early naming convention for thymus-derived fractions and does not imply that the peptide acts as a hormone in the classical endocrine sense.
Biologically, the peptide is studied mainly in the context of immune cell development and regulation. It is produced in the thymus and in several other tissues, and it appears to influence the maturation and activity of T cells and other immune populations. Laboratory work describes effects on cytokine production, on the balance between T cell subsets, and on the function of dendritic cells. Much of this evidence comes from cell culture and animal models, so the extent to which the same pathways operate in humans remains an open question.
The lyophilized peptide is generally stable for extended periods when kept cold and dry. Once dissolved, aqueous solutions are less stable; hydrolysis, oxidation, and aggregation can degrade the material. Storage at -20 °C or lower slows these processes. Repeated freeze-thaw cycles are best avoided because they can promote aggregation. The exact shelf life depends on formulation, pH, and concentration, so stability studies are typically performed for each specific product.
Quality control for thymosin alpha-1 focuses on identity, purity, and potency. Identity is confirmed by mass spectrometry and amino acid analysis, while purity is assessed by chromatography with limits on related substances and residual solvents. Potency assays may use cell-based immune readouts, but these are not standardized across laboratories. Regulatory status differs by jurisdiction; no product is approved in the United States for clinical use, whereas some other countries register injectable forms for specific indications.
The propionyl-CoA is later converted into succinyl-CoA through biotin-dependant propionyl-CoA carboxylase (PCC) and Vitamin B12-dependant methylmalonyl-CoA mutase (MCM), sequentially. Succinyl-CoA is first converted to malate, and then to pyruvate where it is then transported to the matrix to enter the citric acid cycle. In the liver oxaloacetate can be wholly or partially diverted into the gluconeogenic pathway during fasting, starvation, a low carbohydrate diet, prolonged strenuous exercise, and in uncontrolled type 1 diabetes mellitus. Under these circumstances, oxaloacetate is hydrogenated to malate, which is then removed from the mitochondria of the liver cells to be converted into glucose in the cytoplasm of the liver cells, from where it is released into the blood. In the liver, therefore, oxaloacetate is unavailable for condensation with acetyl-CoA when significant gluconeogenesis has been stimulated by low (or absent) insulin and high glucagon concentrations in the blood. Under these conditions, acetyl-CoA is diverted to the formation of acetoacetate and beta-hydroxybutyrate. Acetoacetate, beta-hydroxybutyrate, and their spontaneous breakdown product, acetone, are frequently, but confusingly, known as ketone bodies (as they are not "bodies" at all, but water-soluble chemical substances). The ketones are released by the liver into the blood.
Quantum mechanics is another domain where there is a continuity equation related to conservation of probability. The terms in the equation require the following definitions, and are slightly less obvious than the other examples above, so they are outlined here:
"The Omega Glory" is the twenty-third episode of the second season of the American science fiction television series Star Trek. Written by Gene Roddenberry and directed by Vincent McEveety, it was first broadcast March 1, 1968. In the episode, Captain Kirk must find the cure to a deadly disease and put an end to another Starfleet captain's cultural interference. The story was one of three outlines submitted for selection as the second pilot of Star Trek, the others being "Mudd's Women" and "Where No Man Has Gone Before". Retrospective reviews of "The Omega Glory" rank it among the worst episodes of the original series.
Sources: en.wikipedia.org
== Pharmacology == Like Δ9-THC, 11-hydroxy-THC is a partial agonist at the cannabinoid receptor CB1, but with significantly higher binding affinity (Ki = 0.37 nM compared to Δ9-THC Ki = 35 nM). With respect to cAMP inhibition at CB1 it displays a similar potency to that of Δ9-THC (EC50 = 11 nM vs. EC50 = 5.2 nM, respectively), but a lower maximum response, i.e., efficacy (Emax = 28% vs. Emax = 70%).
Many exercises are partially aerobic and anaerobic; for example, soccer and rock climbing. The presence of lactic acid has an inhibitory effect on ATP generation within the muscle. It can even stop ATP production if the intracellular concentration becomes too high. However, endurance training mitigates the buildup of lactic acid through increased capillarization and myoglobin. This increases the ability to remove waste products, like lactic acid, out of the muscles in order to not impair muscle function. Once moved out of muscles, lactic acid can be used by other muscles or body tissues as a source of energy, or transported to the liver where it is converted back to pyruvate. In addition to increasing the level of lactic acid, strenuous exercise results in the loss of potassium ions in muscle. This may facilitate the recovery of muscle function by protecting against fatigue. Delayed onset muscle soreness is pain or discomfort that may be felt one to three days after exercising and generally subsides two to three days later. Once thought to be caused by lactic acid build-up, a more recent theory is that it is caused by tiny tears in the muscle fibers caused by eccentric contraction, or unaccustomed training levels. Since lactic acid disperses fairly rapidly, it could not explain pain experienced days after exercise. A meta-analysis of 15 studies compared the average number of steps walked per day to the risk of mortality, both for adults over 60 years old and for adults under 60 years old.
== Diagnosis == AGAT deficiency can be suspected from clinical findings, although there is significant phenotypic overlap with the most common presenting symptoms of intellectual disability and muscle weakness. Laboratory testing of plasma and urine will show decreased levels of creatine and guanidinoacetate. Non-specific elevations of metabolites on urine testing that are normalized to creatinine may appear falsely elevated. Magnetic resonance spectroscopy (MRS) of the brain will also show an absence of creatine, which is normally present. This finding is not specific to AGAT deficiency, it can be observed in all three cerebral creatine deficiencies. The combination of biochemical testing and MRS findings can be strongly suggestive of AGAT deficiency. Confirmation would most often be done with molecular testing of GATM. Identification of biallelic pathogenic variants in GATM would be confirmation of a diagnosis of AGAT deficiency. Uncertain findings on molecular testing may be able to be confirmed by enzyme assays, or by measuring creatine uptake in fibroblasts. Prenatal testing for AGAT deficiency can be performed on chorionic villi samples if the causative pathogenic variants in the family are known.
Sources: en.wikipedia.org
=== Neuromuscular adaptations === Strength training is not only associated with an increase in muscle mass, but also an improvement in the nervous system's ability to recruit muscle fibers and activate them at a faster rate. Neural adaptations can occur in the motor cortex, the spinal cord, and/or neuromuscular junctions. The initial significant improvements in strength amongst new lifters are a result of increased neural drive, motor unit synchronization, motor unit excitability, rate of force development, muscle fiber conduction velocity, and motor unit discharge rate. Together, these improvements provide an increase in strength separate from muscle hypertrophy. Typically, the main barbell lifts – squat, bench, and deadlift – are performed with a full range of motion, which provides the greatest neuromuscular improvements compared to one-third or two-thirds range of motion. However, there are reasons to perform these lifts with less range of motion, particularly in the powerlifting community. By limiting range of motion, lifters can target a specific joint angle in order to improve their sticking points by training their neural drive. Neuromuscular adaptations are critical for the development of strength, but are especially important in the aging adult population, as the decline in neuromuscular function is roughly three times as great (≈3% per year) as the loss of muscle mass (≈1% per year). By staying active and following a resistance training program, older adults can maintain their movement, stability, balance, and independence.
On the basis of the type of human cells/tissues that have been used for engraftment, humanized mouse models for cancer can be classified as patient-derived xenografts or cell line-derived xenografts. PDX models are considered to retain the parental malignancy characteristics at a greater extent and hence these are regarded as the more powerful tool for evaluating the effect of anticancer drugs in pre-clinical studies. Humanized mouse models for studying cancers of various organs have been designed. A mouse model for the study of breast cancer has been generated by the intrahepatic engraftment of SK-BR-3 cells in NSG mice. Similarly, NSG mice intravenously engrafted with patient-derived AML cells, and those engrafted (via subcutaneous, intravenous or intra-pancreatic injections) with patient-derived pancreatic cancer tumors have also been developed for the study of leukemia and pancreatic cancer respectively. Several other humanized rodent models for the study of cancer and cancer immunotherapy have also been reported.
The strain lacked the outer membrane proteins OmpF and OmpC, and showed increased expression of a multidrug efflux pump, but did not produce carbapenemase. CR Pseudomonas aeruginosa is commonly present in intensive-care units, and can lead to dangerous infections. In Thai hospitals, of 261 multidrug-resistant samples collected of P. aeruginosa (not part of the Enterobacteriaceae), 71.65% were carbapenem-resistant.
=== February === 1 February A ban on owning an American XL Bully dog comes into force in England and Wales. It is now a criminal offence to own one of the dogs unless the owner has successfully applied for the dog to be exempt. The Bank of England holds interest rates at 5.25%. Climate activist Greta Thunberg appears at Westminster Magistrates' Court, charged with breaching section 14 of the Public Order Act 1986. Her case, and that of four co-defendants, is thrown out the following day. COVID-19 vaccination in the United Kingdom: The first private service for COVID-19 vaccination begins rolling out to pharmacies around the UK, allowing those who are under 65 to receive the latest booster. 2 February Senior Labour MP Darren Jones confirms that the party has ditched its commitment to spend £28bn a year on green investment schemes if it wins the next general election. The killers of 16-year-old transgender girl Brianna Ghey are named as Scarlett Jenkinson and Eddie Ratcliffe, both aged 15 at the time of the murder in February 2023. They are sentenced at Manchester Crown Court to minimum terms of 22 and 20 years, respectively. Water UK, the umbrella trade organisation for the UK's water companies, says that the average annual water bill is expected to increase by 6% in England and Wales from April, an average rise of £27 to £473. 3 February 2024 Northern Ireland Executive formation: The Northern Ireland Assembly meets to elect a new Speaker. Edwin Poots, a former leader of the DUP, is chosen to be the Assembly's 7th Speaker.
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.
The lyophilized powder is kept refrigerated at 2 to 8 degrees Celsius and protected from light. Reconstituted solutions should be used promptly. Freezing and thawing repeatedly is avoided.