synthetic peptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-01-04 and is reviewed periodically as new material appears.
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.
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.
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.
| 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 |
Thymosin alpha-1 is supplied as a lyophilized powder in most research settings. The solid dissolves readily in water and in common aqueous buffers, and it is typically reconstituted shortly before use. Solutions are clear and colourless at ordinary working concentrations. Because the peptide is hygroscopic, weighing and reconstitution are usually performed with minimal exposure to ambient air. Aliquots are prepared to avoid repeated freeze-thaw cycles, and working solutions are kept cold.
Long-term storage is generally at minus twenty degrees Celsius or colder, preferably desiccated and protected from light. Lyophilized material is more stable than reconstituted solution, which degrades faster at room temperature. Stability depends on pH, ionic strength, and the presence of oxidising agents. Published stability data for the peptide are limited, so storage claims in catalogues should be treated as general guidance rather than measured guarantees. Freeze-thaw cycles are kept to a minimum.
Identity and purity are normally confirmed by reversed-phase high-performance liquid chromatography and mass spectrometry. The expected mass for the acetylated 28-residue peptide is close to 3108 daltons, and a mass shift indicates a modification or truncation. Peptide mapping after enzymatic digestion can resolve sequence-level questions. Counter-ion content, water content, and residual solvents are separate quality attributes that a certificate of analysis may or may not report. Aggregation is monitored by size-exclusion chromatography when relevant.
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.
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.
Lyophilized material is generally held at reduced temperature to slow degradation, and storage at minus twenty degrees Celsius or lower is common practice for long-term retention. Short-term working portions are often kept between two and eight degrees Celsius. Once dissolved, the peptide is less stable than the dry powder, and repeated freeze-thaw cycles are associated with loss of material and with aggregate formation. Vials are usually allowed to reach room temperature before opening so that condensation does not introduce moisture, and solutions are protected from light where practical.
Identity and purity are assessed mainly by reversed-phase high-performance liquid chromatography, which separates the peptide from closely related impurities and from truncated or oxidized variants. Mass spectrometry supplies the molecular mass and confirms the expected sequence length, while amino acid analysis can be used to check composition. Because the molecule has no chromophore beyond the peptide backbone, ultraviolet detection is typically performed at a low wavelength, where baseline interference from solvents and buffers is a practical concern. Water content and counter-ion content are often reported alongside purity.
Practical handling focuses on limiting adsorption and contamination. The peptide dissolves readily in water, and dilute solutions tend to adhere to plastic and glass surfaces, so an inert carrier protein or a defined buffer can reduce losses in laboratory work. Workers also record the counter-ion form, since an acetate or trifluoroacetate salt changes the mass balance of the weighed powder. Documentation of lot number, purity value, and storage history supports reproducibility when results from different laboratories are compared.
where J0(λnr/R) is the Bessel function of the first kind of order zero and λn are the positive roots of this function and J1(λn) is the Bessel function of the first kind of order one. As t → ∞, Poiseuille solution is recovered.
Watson was selected at pick 40 under the father–son rule in the 2002 national draft. He was initially coached as a key forward by Kevin Sheedy, who also coached his father Tim. His poor kicking by AFL standards drew criticism, and it was determined that he would be more suited to the midfield at Essendon. At the time, his weight was criticised by the media, as he was overweight for an AFL player. Over the next two seasons, he began to develop his craft in the Essendon midfield and became one of the competition's elite midfielders. Watson had a consistent season in 2009, polling ten Brownlow Medal votes and winning the Essendon best-and-fairest award, the Crichton Medal. Watson polled 335 votes in 15 of the 21 games he played in the 2009 season, with only one game missed due to an ankle injury. Watson was 46 votes ahead of runner-up Dustin Fletcher, who polled 289 votes. By the end of the 2009 season, Watson had gathered a reputation as Essendon's most important midfielder (coming first in the club's overall clearances) and improved his once-criticised kicking ability to above the standard of an AFL player. Watson was announced as Essendon captain on 21 December 2009, taking over from retired goalkicker Matthew Lloyd. Despite Essendon suffering a disappointing 2010 season, winning only seven games and finishing 14th on the AFL ladder, Watson enjoyed a successful first year as captain.
== Taxonomy == This species is named in honor of Keisuke Ito, a Japanese physician and biologist. A named cultivar of this species, "Koidzumi", refers to botanist Gen'ichi Koizumi. The Japanese name of Angelica keiskei, "ashitaba" (tomorrow-leaf), stems from the above-average regenerative capabilities it exhibits after injury.
During an episode of Superstars, old friend Brian Pillman conducted an interview with Austin regarding his upcoming match. After Pillman inadvertently complimented Hart, Austin grew angry and attacked him. He then proceeded to wedge Pillman's ankle in between a steel chair and stomp on it, breaking his ankle in storyline. It would lead to the infamous "Pillman's got a gun" segment on Raw wherein Austin broke into Pillman's home while he was nursing his injury. At Survivor Series, Austin met Hart as expected in a match to determine the number-one contender for the WWF Championship, in what would be Austin's first major PPV match in his WWF career. Hart defeated Austin by using a turnbuckle to push himself backward while locked in the Million Dollar Dream, in a match that lasted almost half an hour. Despite the loss and his status as a heel character, Austin received significant cheers from the crowd. During the 1997 Royal Rumble match, Austin was originally eliminated by Hart but the officials did not see it; he snuck back into the ring and eliminated Hart by throwing him over the ropes, winning the match. This led to the first-ever PPV main event of Austin's WWF career at In Your House 13: Final Four, where he competed in a four corners elimination match against Hart, The Undertaker, and Vader for the vacant WWF Championship. Austin was eliminated early from the match after injuring his knee; Hart would win the match and the championship. Hart lost the championship the next night on Raw to Sycho Sid due to Austin's interference, continuing their feud.
Sources: en.wikipedia.org
2011: Icon acquired Oxford Outcomes, an international health outcomes consultancy and Firecrest Clinical, a technology provider specialising in site performance and study management 2012: Icon acquired PriceSpective, a global value strategy consultancy and Chinese CRO, BeijingWits 2013: Icon acquired staffing and FSP providers, ClinForce and Assent and Akos, an EU provider of pharmacovigilance and drug safety services 2014: Icon acquired Aptiv Solutions, a market leader in adaptive trial design and execution 2015: Icon acquired MediMedia Pharma Solutions to enhance market access and scientific communications capabilities, and PMG Research Inc., an integrated network of clinical research sites in the US 2016: Icon acquired Clinical Research Management Inc., to extend its presence in the government-sponsored research market 2017: Icon acquired MAPI Group, thereby becoming the world's second-largest provider of late-phase services 2019: Icon acquired Symphony Clinical Research, a leading provider of at-home patient services and site-support services; MediNova, an integrated network of clinical research sites across EMEA; and MolecularMD, to enhance its laboratory offerings in molecular diagnostic testing and immunohistochemistry 2020: Icon acquired MedPass International, a leading European medical device CRO, regulatory and reimbursement consultancy 2021: Icon acquired PRA Health Sciences, a competitor offering clinical research services, for US$12 billion.
=== BrMASS Manuel Riveros Medal === 2024 Livia S. Eberlin, Debora Azevedo 2022 Lidija Nikolaevna Gall, Julia Laskin, Claudia Moraes de Rezende, Rosa Erra-Balsells Maria Fernanda Georgina Gine Rosias Conchetta Cacheres
Topical hydrocortisone is a drug under the class of corticosteroids, which is used for the treatment of skin inflammation, itchiness and allergies. Some examples include insect bites, dermatitis and rash. Hydrocortisone was discovered by Nobel laureates Edward C. Kendall and Philip S. Hench in the 1930s while they were conducting research on rheumatoid arthritis. Its topical use was first recorded in the 1950s. The most common adverse effects after the application of topical hydrocortisone are burning and stinging sensations. Side effects after long-term usage include eyesight damage, elevated blood sugar levels and adrenal gland disorders. Topical hydrocortisone is available in several dosage forms such as solution, lotion, cream, ointment and spray. Some brand names for topical hydrocortisone include Anusol HC, Cortizone 10, and Synacort.
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 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.