Everything below concerns mass spectrometry. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-01-30. Where a claim depends on a specific study, the study is described rather than over-claimed.
Several names appear in the literature for this peptide, including thymalfasin and the abbreviation T-alpha-1. Naming conventions differ among research articles, regulatory documents, and supplier catalogs, which complicates literature searches. Both synthetic and recombinant production routes yield a peptide with the same 28-residue sequence as the thymic isolate. Because the thymosin label also covers unrelated peptides, sources should be compared by sequence rather than by name alone.
The peptide occurs naturally in thymic tissue and has been detected in serum and other biological fluids. Reported concentrations are low, and reliable measurement generally requires immunoassay or mass spectrometry with an enrichment step. It is released from a larger precursor, prothymosin alpha, by proteolytic cleavage, although the enzymes involved are not fully characterized. Whether circulating levels reflect thymic output specifically remains an open question.
Thymosin alpha 1 is a 28-amino-acid peptide first isolated from thymosin fraction 5, a bovine thymic extract. Its sequence begins with an acetylated serine residue and carries a high proportion of acidic residues, so the molecule has a net negative charge near neutral pH. Despite the shared name, it is unrelated in sequence to the thymosin beta family. Synthetic material prepared by solid-phase peptide synthesis is identical in sequence to the natural peptide.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C129H215N33O55 | Calculated for the acetylated 28-residue peptide |
| Appearance | White to off-white powder | Lyophilized solid recovered from aqueous buffer |
| Solubility | Freely soluble in water | Typically dissolved in water or buffer before use |
| Typical storage | -20 C or below, desiccated | Protect from light and avoid repeated freeze-thaw cycles |
| Identity testing | Reverse-phase HPLC with mass spectrometry | Retention time and measured mass confirm the sequence |
The peptide lacks cysteine, methionine, and tryptophan, so disulfide scrambling and sulfur oxidation are not major degradation routes. Instead, aspartate residues can undergo isomerization or cyclization to succinimide intermediates, generating isoaspartate variants. Hydrolysis of peptide bonds also occurs slowly in solution. These changes may reduce biological activity even when the main peak remains detectable. Stability studies therefore track both potency and the appearance of related substances.
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.
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.
Clinical interest has centered on chronic viral hepatitis, on immune restoration in various conditions, and on use as an adjuvant intended to improve responses to vaccines. Trials have reported mixed results, and regulatory status differs sharply between countries; in some places it is a prescription product, while elsewhere it is sold without an approved therapeutic indication. Because published studies vary widely in design, population, and endpoints, comparisons across them are difficult and no single conclusion covers the whole literature.
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.
Quantifying thymosin alpha-1 in a sample usually relies on reverse-phase high-performance liquid chromatography. The peptide lacks strong chromophores, so detection often occurs at 214 nm, where the peptide backbone absorbs. Mass spectrometry provides confirmatory identification and can detect sequence variants or truncations. Immunoassays have been used in biological matrices, but they may cross-react with related fragments. For purity assessment, chromatographic peak area gives the main component percentage, while mass accuracy verifies molecular identity.
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.
The ability to quantitate the βhCG level is useful in monitoring germ cell and trophoblastic tumors, follow-up care after miscarriage, and diagnosis of and follow-up care after treatment of ectopic pregnancy. The lack of a visible fetus on vaginal ultrasound after βhCG levels reach 1500 mIU/mL is strongly indicative of an ectopic pregnancy. Still, even an hCG over 2000 IU/L does not necessarily exclude the presence of a viable intrauterine pregnancy in such cases. As pregnancy tests, quantitative blood tests and the most sensitive urine tests usually detect hCG between 6 and 12 days after ovulation. It must be taken into account, however, that total hCG levels may vary in a very wide range within the first 4 weeks of gestation, leading to false results during this period. A rise of 35% over 48 hours is proposed as the minimal rise consistent with a viable intrauterine pregnancy.
It is believed that the tyrosine amino acid found along the amino acid sequence of alpha-sarcin allows for the specificity when alpha-sarcin binds to the rRNA. It is the alcohol group found on the tyrosine amino acid that allows for this binding. This was determined in tests that removed the alcohol group, replacing tyrosine with phenylalanine, and the binding affinity was greatly reduced. The region of the DNA that makes alpha-sarcin is highly conserved, along with the corresponding sequence on the targeted ribosome. The corresponding sequence on the targeted ribosome is a centered around a guanine nucleotide located on what is called the "bulged-G motif".
Silicon (14Si) has 25 known isotopes, with mass number ranging from 22 to 46. 28Si (the most abundant isotope, at 92.24%), 29Si (4.67%), and 30Si (3.07%) are stable. The longest-lived radioisotope is 32Si, which occurs naturally in tiny quantities from cosmic ray spallation of argon. Its half-life has been determined to be approximately 157 years; it beta decays with energy 0.21 MeV to 32P, which in turn beta-decays, with half-life 14.269 days to 32S; neither step has gamma emission. After 32Si, 31Si has the second longest half-life at 157.2 minutes. All others have half-lives under 7 seconds.
[Citation Needed] All of the above have been, owing to their somewhat sophisticated yet straightforward synthesis from pharmaceutical opioids, consistently if in vanishingly small quantities since at least the 1960s by law enforcement around the world as the results of clandestine synthesis, and acetylmorphone itself was banned by the League of Nations in 1930 to prevent its use as a legal heroin substitute.[Citation Needed][Relevance] Therefore, all or most of this group and its hydromorphone analogues along with some others more closely related to heroin such as acetylpropionylmorphine were the first designer drugs in the 1920s.
Henriksen states that ice-nine represents a collaboration between science and the military that, as with the atomic bomb, proves their "indifference to the fate of the human race", and the "inhuman and immoral results of [...] pure research". The book notes that the pure search for knowledge without "living human principles" as depicted in Cat's Cradle ultimately tarnishes science.
Sources: en.wikipedia.org
The greater sac, represented in red in the diagrams above. The lesser sac, represented in blue. The lesser sac is divided into two "omenta": The lesser omentum (or hepatogastric) is attached to the lesser curvature of the stomach and the liver. The greater omentum (or gastrocolic) hangs from the greater curvature of the stomach and loops down in front of the intestines before curving back upwards to attach to the transverse colon. In effect it is draped in front of the intestines like an apron and may serve as an insulating or protective layer. The mesentery is the part of the peritoneum through which most abdominal organs are attached to the abdominal wall and supplied with blood and lymph vessels and nerves.
== Principles and history == Water was the original coolant for internal combustion engines. It is cheap, nontoxic, and has a high heat capacity. It however has only a 100 Kelvin liquid range, and it expands upon freezing. To address these problems, alternative coolants with improved properties were developed. Freezing and boiling points are colligative properties of a solution, which depend on the concentration of dissolved substances. Salts, for example, lower the melting points of aqueous solutions and as such are commonly used for de-icing due to their low cost. However, salt solutions typically cannot be used in cooling systems because they induce corrosion of metals. Solutions of organic compounds, especially alcohols, in water are effective. Alcohols such as methanol, ethanol, ethylene glycol, etc. have been the basis of all antifreezes since they were commercialized in the 1920s.
Aviv (1981), surgeon known for inventing the Flexible Endoscopic Evaluation of Swallowing with Sensory Testing technique and developing the transnasal esophagoscopy method Adrian R. Krainer (1981), co-winner of the 2018 Breakthrough Prize in Life Sciences Neil Shubin (1982), paleontologist and co-discoverer of Tiktaalik, provost of the Field Museum of Natural History Michael Travisano (1983), evolutionary biologist and professor at University of Minnesota, Twin Cities Peter Lunenfeld (1984), critic and theorist of digital media Peter Marks (1985), director of the Center for Biologics Evaluation and Research and member of the White House Coronavirus Task Force James Nowick (1985), professor of chemistry at the University of California, Irvine Eric M. Genden (1987), head and neck surgeon who performed the first jaw transplant using the patient's jaw and bone marrow Geoffrey Miller (1987), psychologist, professor at the University of New Mexico Leslie B. Vosshall (1987), neurobiologist known for her contributions in the field of olfaction Patrick Ball (1988), data scientist, executive director of the Human Rights Data Analysis Group Rebecca N. Wright (1988), computer scientist and professor at Barnard College, former director at DIMACS Jonathan Rosand (1989), professor of neurology at Harvard Medical School, son of art historian David Rosand '59 Christopher S.
== History == The term "hydrocolloid" was coined in the 1960s during the development of mucoadhesives, first used to treat mouth ulcers. The term was later adopted for a new dressing type in which a hydrophilic gelable mass was applied to a flexible semipermeable carrier. It was first sold under the brand Granuflex in the United Kingdom in 1982, and then DuoDERM in the United States in 1983. Different products subsequently came to market with slightly varying formulations, designed for specific areas of the body or specific purposes (for example, postoperative dressings). More recently, the term has sometimes been used to describe hydrogel dressings which are fundamentally different to hydrocolloid dressings.
Following Val Belcher's retirement from professional football, Belcher began a successful career as a restaurant entrepreneur. In 1986, Belcher founded the Lone Star Cafe restaurant with former Ottawa Rough Rider teammate Larry Brune in the Ottawa suburb of Nepean. Over the years, it expanded into a franchise business. It was renamed Lone Star Texas Grill, operating under the Lone Star Group of Companies. As of 2020, Lone Star Texas Grill operates over 20 locations across southern and eastern Ontario, including seven in the Greater Ottawa Area where it originated, as a family-style restaurant specializing in wood-fire grill fajitas, authentic Tex-Mex fare and frozen margaritas.
Sources: en.wikipedia.org
These crystals stop growing at the point where the TZ will eventually fully transition to the SSZ. Researchers determined that this particular point marks the position where the suspension is in an equilibrium state (i.e. freezing temperature and suspension temperature are equal). We can say then that the size of the initial and transition zones are controlled by the extent of supercooling beyond the already low freezing temperature. If the freeze-casting setup is controlled so that nucleation is favored at only small supercooling, then the TZ will give way to the SSZ sooner.
Insulin therapy can be injection under the skin multiple times a day, or can be delivered continuously as a basal amount with boluses for high blood sugar or before meals using an insulin pump. A diabetic diet, exercise, and lifestyle modifications are considered cornerstones of management. If left untreated, type 1 diabetes results in death. Type 1 diabetes can cause many complications if blood sugar control is not very well controlled. Complications of relatively rapid onset include diabetic ketoacidosis and nonketotic hyperosmolar coma. Long-term complications include heart disease, stroke, kidney failure (Diabetic Nephropathy), foot ulcers, and damage to the eyes (diabetic retinopathy). As insulin lowers blood sugar levels, complications may arise from low blood sugar if more insulin is taken than necessary. Type 1 diabetes makes up an estimated 5–10% of all diabetes cases. The number of people affected globally is unknown, although it is estimated that about 80,000 children develop the disease each year. Within the United States the number of people affected is estimated to be one to three million. Rates of disease vary widely, with approximately one new case per 100,000 per year in East Asia and Latin America and around 30 new cases per 100,000 per year in Scandinavia and Kuwait. It typically begins in children and young adults but can begin at any age.
=== Contestants === 1st - Karl Fong, Bakery Owner from Hercules, California 2nd - Jessica Brockway, Bakery Owner from Seattle, Washington 3rd - Pete Tidwell, Bakery Owner from Provo, Utah 4th - Julie Montgomery, Pastry Instructor from Toronto, Canada 5th - Jocelyn Jung, Bakery Owner from San Diego, California 6th - Sheldon Taylor-Timothy, Home Baker from Toronto, Canada 7th - Brittany Lombardi, Pastry Cook from The Bronx, New York 8th - Jess Eddy, Bakery Owner from Hartland, Wisconsin
==== United States ==== As of 2018, Zipline was working with the FAA to develop rules for drone operation beyond the line of sight. During the COVID-19 pandemic in 2020, the FAA granted a Part 107 waiver to Novant Health in partnership with Zipline for the delivery of medical supplies and personal protective equipment to facilities in North Carolina. The company plans to offer deliveries to homes. On November 18, 2021, Zipline started a trial service with Walmart for e-commerce shopping deliveries in Pea Ridge, Arkansas. The service, selectable to online shoppers using a special mobile app, could deliver to all residences within 50 miles (80 km) of a particular Walmart store in Pea Ridge during daylight hours. On June 21, 2022, the license "Package Delivery by Drone (Part 135)" was granted. On October 4, 2022, Zipline began commercial delivery services in Salt Lake City, Utah, in partnership with Intermountain Healthcare. On September 18, 2023, the FAA announced it had authorized Zipline to begin making commercial deliveries beyond the line of sight without visual observers. In April 2025, Zipline began making deliveries for Walmart in the Dallas–Fort Worth metroplex using Platform 2 drones.
Sources: en.wikipedia.org
It is a 28-amino-acid peptide originally purified from a bovine thymic extract and later produced synthetically. It is studied mainly for its effects on immune cell function.
No. The two peptides share part of a name but differ in length, sequence, and net charge. Literature searches that treat them as one compound return misleading results.
Solid-phase peptide synthesis is the usual route, and recombinant expression has also been described. Both approaches produce material matching the natural sequence.
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.