The short version of Thymosin fraction 5 fits in a sentence. The long version — which is the one that helps — is below.
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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.
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.
Early work on thymic extracts in the 1960s described a heat-stable acidic fraction containing many polypeptides. Separation of that mixture yielded individual components, and thymosin alpha-1 was named as one of them on the basis of assays for T-cell activity. The first preparations came from calf thymus, while subsequent research and clinical material has been chemically synthesized. Nomenclature in older papers is inconsistent, and the same peptide sometimes appears under different designations, which complicates literature searches.
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 |
|---|---|---|
| Chemical class | Synthetic peptide, 28 residues | N-terminal fragment of prothymosin alpha |
| Molecular mass | About 3108 Da | Acetylated form |
| Isoelectric point | Near 4.2 | Acidic peptide |
| Appearance | White to off-white lyophilized powder | Common supplied form |
| Typical storage | -20 °C or below, dry | Solution stability is lower |
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 molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
The peptide is generated in cells by cleavage of prothymosin alpha, a larger acidic protein encoded by the PTMA gene. Prothymosin alpha is expressed in many tissues, not only in the thymus, and its functions include nuclear roles in chromatin-related processes. The 28-residue fragment corresponds to the N-terminal portion of that precursor. How the cleavage occurs and how the fragment's concentration is regulated remain open questions; circulating amounts are small and difficult to measure reliably with routine assays.
Lyophilized material is typically treated as a hygroscopic solid that should be brought to room temperature before the container is opened, which limits condensation on the powder. Reconstitution is commonly done with sterile water or a buffered diluent, and gentle mixing is preferred over vigorous agitation to reduce foaming and surface adsorption. Because peptides can bind to plastic and glass, diluents containing a small amount of carrier protein are sometimes used in laboratory work. Working solutions are generally aliquoted and prepared fresh rather than subjected to repeated freezing and thawing.
Stability depends on temperature, pH, and the number of freeze-thaw events the sample has experienced. Freeze-dried material is commonly held at -20 °C or colder, while reconstituted liquid is kept cold and used within a short window. Extreme pH and prolonged light exposure can promote deamidation, oxidation, or aggregation, particularly at asparagine and methionine positions. Adsorption to container walls can lower the measured concentration of a dilute solution even when the peptide molecules themselves remain intact.
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.
=== Booster preparations === The Atlas booster used for MA-9 sported several technical improvements, most notably an enhanced propulsion system with a hypergolic igniter that would eliminate the need for hold-down time at launch to prevent rough combustion. With seven successful Mercury launches in a row, the failures of the early days seemed like a distant memory by early 1963 and NASA officials had a high degree of confidence in the Atlas that overshadowed its still spotty launch record. At the first meeting of senior MSFC officials for the year (January 11), Walter Williams noted that the Air Force had yet to provide an explanation for two Atlas F failures during the second half of 1962. Until the investigation committees released their findings and cleared the Atlas D of guilt by association, Cooper's flight could be delayed. During the seven months between Schirra's and Cooper's flights, there were five failures of Atlas D vehicles (one of them an Atlas-Agena, the rest operational ICBM tests). NASA did not let its guard down on the Atlas, despite the recent high degree of success enjoyed by Project Mercury. When Atlas 130D received its factory rollout on January 30, it was found to have damaged wiring and had to be sent back for repairs. At his first press conference on February 8, Gordon Cooper admitted to not knowing much about the booster problems and focused instead on the enhancements made to his Mercury capsule.
=== Generic names === Benorterone is the generic name of the drug and its INNTooltip International Nonproprietary Name and USANTooltip United States Adopted Name. It is also known by its developmental code names SKF-7690 and FC-612.
== Early life and education == Meinrad Busslinger was born on 30 July 1952 in Gebenstorf, Switzerland. He grew up in the Swiss town of Zug, where he obtained his grammar school education. From 1972 to 1976, he studied natural sciences at the Swiss Federal Institute of Technology (ETH Zurich), where he majored in biochemistry. During his PhD studies (1976–1981), Busslinger discovered important regulatory elements involved in the transcriptional control of gene expression by investigating the regulation of sea urchin histone genes. He performed his PhD work under the supervision of Max L. Birnstiel at the University of Zurich, from where he received a PhD degree in molecular biology in 1981.
In week three of the development of the embryo, mesenchyme cells from the primitive streak migrate around the cloacal membrane. Early in the fifth week, the cells form two swellings called the cloacal folds. The cloacal folds meet in front of the cloacal membrane and form a raised area known as the genital tubercle. The urorectal septum fuses with the cloacal membrane to form the perineum. This division creates two areas one surrounded by the urethral folds and the other by the anal folds. These areas become the urogenital triangle and the anal triangle. The area between the vulva and the anus is known as the clinical perineum. At the same time, a pair of swellings on either side of the urethral folds known as the genital swellings develop into the labioscrotal swellings. Sexual differentiation takes place, and at the end of week six in the female, hormones stimulate further development and the genital tubercle bends and forms the clitoris. The urogenital sinus persists as the vulval vestibule, vestibular glands and urethra. The urethral folds form the labia minora and the labioscrotal swellings form the labia majora. The uterovaginal canal or genital canal, forms in the third month of the development of the urogenital system. The lower part of the canal is blocked off by a plate of tissue, the vaginal plate. This tissue develops and lengthens during the third to fifth months and the lower part of the vaginal canal is formed by a process of desquamation or cell shedding.
Sources: en.wikipedia.org
Borodinsky bread is a slightly sweet sourdough rye bread of Russian origin, usually flavoured by caraway and coriander seeds and sweetened with molasses, which augments its already quite dark colour coming from the rye flour. It is named after the Battle of Borodino, and the legend says that it was invented by the widow of one of the Russian generals who died in that battle, though in reality it was probably created much later, at the end of the 19th century.
The serine has an -OH group that is able to act as a nucleophile, attacking the carbonyl carbon of the scissile peptide bond of the substrate. A pair of electrons on the histidine nitrogen has the ability to accept the hydrogen from the serine -OH group, thus coordinating the attack of the peptide bond. The carboxyl group on the aspartic acid in turn hydrogen bonds with the histidine, making the nitrogen atom mentioned above much more electronegative. The whole reaction can be summarized as follows:
Besides that, maintaining a prolonged strict oral hygiene through proper intrasulcular toothbrushing technique could promote the keratinisation of the sulcular epithelium through the elimination of the bacterial flora within the sulcus. However, the clinical significance of the keratinisation of sulcular epithelium remains questionable as its contribution to the strength of the semi-permeable barrier is minimal and inducing keratinisation is also suggested to interfere with the healing process in periodontitis or after surgery. Others also warn against keratinisation of the adjacent junctional epithelium which could compromise its attachment to the tooth, defeating its purpose as a physical barrier.
Joy Osmanski as Paula Brooks / Tigress (season 3; recurring season 1; guest season 2):A member of the ISA who hunts the world's most dangerous humans. She is a gym teacher at Blue Valley High, the wife of "Crusher" Crock, and mother of Artemis Crock. In the second season, she breaks out of prison twice. In the third and final season, she moves in next door to the Whitmore-Dugans. Joel McHale as Sylvester Pemberton / Starman and Gerard Shugel / Ultra-Humanite (season 3; guest season 1; recurring season 2):A member of the original JSA who used an anti gravity Cosmic Staff invented by scientist Ted Knight that Courtney later finds. In the present, Ultra-Humanite forms an alliance with Icicle and Dragon King before transplanting his brain into Sylvester Pemberton's body in order to manipulate Stargirl and her JSA, and Dragon King's brain into Ultra-Humanite's albino gorilla body for him to "defeat" as Starman alongside Jordan's son before intending to run for president as a mouthpiece for Icicle to spread his ideals.
=== Objectification === Hooters has been criticized for objectifying women. The Orange County National Organization for Women (NOW), as well as three other California chapters, filed a complaint against Hooters with several district attorneys in 2010. They criticized Hooters for “having it both ways” and operating as a “legal bait and switch” by simultaneously advertising itself as a “family restaurant” and allowing minors, while defending itself against charges of sex discrimination by claiming that the restaurant is based on female sex appeal. The complaint called on authorities to either force Hooters to stop admitting children onto the premises or stop sex discrimination in its hiring practices. Several studies suggest that working at Hooters and other "breastaurants" takes a psychological toll on its employees, with higher levels of objectification being associated with lower job satisfaction, and higher levels of anxiety and eating disorders. However, others have argued that feminism is about having a choice and that being able to work as a woman in whichever industry the individual woman in question chooses along with the ability for women to make their own money is empowering. Hooters in response to such criticism have said the company regularly donates to charities that help promote women's entrepreneurship and often promote Hooters Girls to management positions. 40% of Hooters restaurants managers are reportedly female.
Sources: en.wikipedia.org
In line with its role as a first line defense system, SP is released when toxicants or poisons come into contact with a range of receptors on cellular elements in the chemoreceptor trigger zone, located in the floor of the fourth ventricle of the brain (area postrema). Presumably, SP is released in or around the nucleus of the solitary tract upon integrated activity of dopamine, serotonin, opioid, and/or acetylcholine receptor signaling. NK1Rs are stimulated. In turn, a fairly complex reflex is triggered involving cranial nerves responsible for respiration, retroperistalsis, and general autonomic discharge. The actions of aprepitant are said to be entirely central, thus requiring passage of the drug into the central nervous system. However, given that NK1Rs are unprotected by a blood brain barrier in the area postrema just adjacent to neuronal structures in the medulla, and the activity of sendide (the peptide based NK1RA) against cisplatin-induced emesis in the ferret, it is likely that some peripheral exposure contributes to antiemetic effects, even if through vagal terminals in the clinical setting.
In March 2007, in the final verdict by the Supreme Court of Cassation, stated that "in the years of 1994 to 1998 there was no ascertained positive case of doping substances by Juventus players, that the purchase of erythropoietin or its administration to the athletes of the club does not emerge from any act of the trial, and that the same expert had identified the possibility of an administration of erythropoietin in distant terms from the sure evidence ("very probable" and in two cases "practically certain"): it is that therefore, the judgement of probability and not of certainty, did not allow for a statement of responsibility." The verdict also went on to say: "In response to the conclusion taken, the territorial court notes that there were no deferred values higher than the limits set in the various antidoping protocols and that the situation of the Juventus players, both with reference to the average hematological values, and in relation to that of material balance, did not differ from the national average population.
Hidden stops are non-stop codons that would be read as stop codons if they were frameshifted +1 or −1. These prematurely terminate translation if the corresponding frame-shift (such as due to a ribosomal RNA slip) occurs before the hidden stop. It is hypothesised that this decreases resource wastage on nonfunctional proteins and the production of potential cytotoxins. Researchers at Louisiana State University propose the ambush hypothesis, that hidden stops are selected for. Codons that can form hidden stops are used in genomes more frequently compared to synonymous codons that would otherwise code for the same amino acid. Unstable rRNA in an organism correlates with a higher frequency of hidden stops. However, this hypothesis could not be validated with a larger data set. Stop-codons and hidden stops together are collectively referred as stop-signals. Researchers at University of Memphis found that the ratios of the stop-signals on the three reading frames of a genome (referred to as translation stop-signals ratio or TSSR) of genetically related bacteria, despite their great differences in gene contents, are much alike. This nearly identical genomic-TSSR value of genetically related bacteria may suggest that bacterial genome expansion is limited by their unique stop-signals bias of that bacterial species.
== Services == The Instituto Universitario de Restauración del Patrimonio is divided into two areas: the area of intervention in the Pictorial and Sculptural Heritage and the area of intervention in the Architectural Heritage, and a Training and Dissemination area. The area of intervention in the pictorial and sculptural heritage operates in both basic research and applied research in seeking to acquire new knowledge to develop new products, techniques, processes, methods and systems that improve existing ones. The area of intervention in the Pictorial and Sculptural Heritage consist in restoration workshops:
Sources: en.wikipedia.org
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.
Thymosin alpha-1 is a single defined 28-residue peptide, while the broader family includes unrelated peptides such as thymosin beta-4. The shared name reflects historical isolation from thymus tissue rather than a common structure. Confusion between the two is common in older literature.
No single pathway fully accounts for its reported effects. Several studies describe interaction with innate immune receptors and downstream cytokine changes, but the complete picture is not settled. Open questions remain about which effects occur at physiological concentrations.
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.