The short version of freeze-thaw cycling 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.
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 |
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.
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.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or chemically modified byproducts. Mass spectrometry confirms the expected molecular mass and can indicate acetylation state or sequence errors. Amino acid analysis and peptide mapping supply complementary sequence-level information, while endotoxin testing is relevant for preparations intended for cell or animal work. Purity figures reported by suppliers refer to the method used and are not directly comparable across laboratories unless conditions are stated.
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.
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.
Terrestrial plants make leaf waxes to coat the surfaces of their leaves, to minimize water loss. These waxes are largely straight-chain n-alkyl lipids. They are insoluble, non-volatile, chemically inert, and resistant to degradation, making them easily preserved in the sedimentary record, and therefore good targets as biomarkers. The main water source for land plants is soil water, which largely resembles the HIC of rain water, but varies between environments and with enrichment by precipitation, depletion by evaporation, and exchange with atmospheric water vapor. There can be a significant offset between the δD value of source water and the δD value of leaf water at the site of lipid biosynthesis. No fractionation is associated with water uptake by roots, a process usually driven by capillary tension, with the one exception of xerophytes that burn ATP to pump water in extremely arid environments (with a roughly 10‰ depletion). However, leaf water can be substantially enriched relative to soil water due to transpiration, an evaporative process which is influenced by temperature, humidity, and the composition of surrounding water vapor. The leaf water HIC can be described with a modified Craig-Gordon model, where ΔDe is the steady state enrichment of leaf water, εeq is the temperature-dependent equilibrium fractionation between liquid water and vapor, εk is the KIE from diffusion between leaf internal air space and the atmosphere, ΔDv is the leaf/air disequilibrium, ea is atmospheric vapor pressure, and ei is internal leaf vapor pressure.
Finally, on June 15, 1977, the general election took place without any incident and with a very high turnout, close to 80% of the census. The victory went to Unión de Centro Democrático, a coalition of moderate parties and "independents" led by Prime Minister Adolfo Suárez, although it failed to achieve an absolute majority in the Congress of Deputies ─ it obtained 34% of the votes and 165 seats: it was 11 seats short of an absolute majority. The second winner was the PSOE, which became the hegemonic party of the left, obtaining 29.3% of the votes and 118 deputies, ousting by a wide margin the PCE, which obtained 9.4% of the votes and remained with 20 deputies, even though it was the party that had borne the greatest weight in the anti-Francoist struggle. The Partido Socialista Popular of Enrique Tierno Galván was also ousted, obtaining only six deputies and 4% of the votes. The other big loser of the elections, together with the PCE, was the neofranquist Alianza Popular of Manuel Fraga who only obtained 8.3% of the votes and 16 deputies ─ 13 of whom had been ministers under Franco. But the biggest setback was suffered by the Christian democracy of Joaquín Ruiz-Giménez and José María Gil Robles, the leader of the CEDA during the Second Republic, who did not obtain any deputies. On the other hand, neither the extreme right nor the extreme left achieved parliamentary representation.
=== Photodynamic (PDT) mechanism === PDT can induce many cellular pathways, and its main purpose is to induce cell death, either by apoptosis or necrosis. The fundamental process of photodynamic reactions involves three elements: photosensitizers (PS), light of a specific wavelength, and oxygen present in the cell. The interaction of these three components produced a desirable effect inside targeted tissues. Apart from light and oxygen, photosensitizers are compounds designed to absorb light at particular wavelengths during therapy, which enables them to initiate therapeutic processes. Two pathway branches interact and contribute to different ratios during PDT therapy, affecting its efficiency. Both mechanisms have the same first stage. When cells absorb photosensitizers and are exposed to light that aligns with their absorption spectrum, these substances photo-excite from their stable ground state (S°) to an energised excited singlet state (S1). Some energy is emitted as fluorescence, remaining energy directs the photosensitizer molecule into triplet state T1. Type I pathway of photodynamic reaction: T1 state PS can then interact with nearby molecules. Energy transfers between the photosensitizer and other molecules in the form of hydrogen and electrons, resulting in the creation of free radicals and anion radicals. These radicals remain in ground state and react with oxygen, leading to the formation of reactive oxygen species (ROS) and superoxide anion radicals (O2•−), which further react with oxygen to generate ROS.
North Korea was one of the first countries to close borders due to COVID-19. Starting from 23 January 2020, North Korea banned foreign tourists, and all flights in and out of the country were halted. The authorities also started placing patients with suspected COVID, including those with slight, flu-like symptoms, in quarantine for two weeks in Sinuiju. On 30 January, the state news agency of North Korea, the Korean Central News Agency (KCNA), declared a "state emergency", and reported the establishment of anti-epidemic headquarters around the country. Though many parts of the border were closed, the bridge between Dandong and Sinuiju remained open and allowed supplies to be delivered. In late February, the North Korean government said that it would keep the border closed until a cure was found. On 2 February, KCNA reported that all the people who had entered the country after 13 January were placed under "medical supervision". South Korean media outlet Daily NK reported that five suspected COVID-19 patients in Sinuiju, on the Chinese border, had died on 7 February. The same day, The Korea Times reported that a North Korean female living in the capital Pyongyang was infected. Although there was no confirmation by North Korean authorities of the claims, the country implemented further strict measures to combat the spread of the virus. Schools were closed starting on 20 February. On 29 February, Supreme Leader Kim Jong Un called for stronger measures to be taken to prevent COVID-19 from spreading within North Korea.
When ice crystals are aligned with their basal planes parallel to the temperature gradient (z-crystals), they can be represented as two resistors in parallel. The thermal resistance of the ceramic is significantly smaller than that of the ice however, so the apparent resistance can be expressed as the lower Rceramic. If the ice crystals are aligned perpendicular to the temperature gradient (r-crystals), they can be approximated as two resistor elements in series. For this case, the Rice is limiting and will dictate the localized thermal conditions. The lower thermal resistance for the z-crystal case leads to lower temperatures and greater heat flux at the growing crystals tips, driving further growth in this direction while, at the same time, the large Rice value hinders the growth of the r-crystals. Each ice crystal growing within the slurry will be some combination of these two scenarios. Thermodynamics dictate that all crystals will tend to align with the preferential temperature gradient causing r-crystals to eventually give way to z-crystals, which can be seen from the following radiographs taken within the TZ. When z-crystals become the only significant crystal orientation present, the ice-front grows in a steady-state manner except there are no significant changes to the system conditions. It was observed in 2012 that, in the initial moments of freezing, there are dendritic r-crystals that grow 5 - 15 times faster than the solidifying front. These shoot up into the suspension ahead of the main ice front and partially melt back.
Sources: en.wikipedia.org
=== Qualitative filter paper === Qualitative filter paper is used in qualitative analytical techniques to determine materials. There are different grades of qualitative filter paper according to different pore size. There are total 13 different grades of qualitative filter paper. The largest pore size is grade 4; the smallest pore size is grade 602 h; the most commonly used grades are grade 1 to grade 4.
In medicine, collateralization, also vessel collateralization and blood vessel collateralization, is the growth of a blood vessel or several blood vessels that serve the same end organ or vascular bed as another blood vessel that cannot adequately supply that end organ or vascular bed sufficiently. Coronary collateralization is considered a normal response to hypoxia and may be induced, under some circumstances, by exercise. It is considered to be protective. Collateral or anastomotic blood vessels also exist even when blood supply is adequate to an area, and these blood vessels are often taken advantage of in surgery. Some notable areas where this occurs include the abdomen, rectum, knee, shoulder, and head.
=== Recreational use === Recreational use of bupropion is uncommon. While bupropion demonstrates some potential for recreational use, this potential is less than that of other commonly used stimulants, being limited by features of its pharmacology. Case reports describe the recreational use of bupropion as producing a "high" similar to cocaine or amphetamine usage but with less intensity. There have been some anecdotal and case-study reports of bupropion abuse, but the bulk of evidence indicates that the subjective effects of bupropion when taken orally are markedly different from those of addictive stimulants such as cocaine or amphetamine. However, bupropion, by non-conventional routes of administration like injection or insufflation, has been reported to be used recreationally in the United States and Canada, notably in prisons. Bupropion has also been encountered as a novel designer drug or adulterant in the United States and Europe.
Thiamine: Thiamine acts as an essential cofactor in glucose metabolism, therefore, it may modulate diabetic complications by controlling glycemic status in diabetic patients. Additionally, deficiency of thiamine was observed to be associated with dysfunction of β-cells and impaired glucose tolerance. Different studies indicated possible role of thiamin supplementation on the prevention or reversal of early stage diabetic nephropathy, as well as significant improvement on lipid profile.
Sources: en.wikipedia.org
Fermentation begins once the growth medium is inoculated with the organism of interest. Growth of the inoculum does not occur immediately. This is the period of adaptation, called the lag phase. Following the lag phase, the rate of growth of the organism steadily increases, for a certain period—this period is the log or exponential phase. After a phase of exponential growth, the rate of growth slows down, due to the continuously falling concentrations of nutrients and/or a continuously increasing (accumulating) concentrations of toxic substances. This phase, where the increase of the rate of growth is checked, is the deceleration phase. After the deceleration phase, growth ceases and the culture enters a stationary phase or a steady state. The biomass remains constant, except when certain accumulated chemicals in the culture chemically break down the cells in a process called chemolysis. Unless other microorganisms contaminate the culture, the chemical constitution remains unchanged. If all of the nutrients in the medium are consumed, or if the concentration of toxins is too great, the cells may become senescent and begin to die off. The total amount of biomass may not decrease, but the number of viable organisms will decrease.
=== Cardiovascular === Medtronic's cardiovascular therapies span the major specialties of interventional cardiology, cardiac surgery, and vascular surgery. The products are used to reduce the potentially debilitating effects of coronary, aortic, and structural heart disease. As of August 2024, cardiovascular portfolio included four product segments - cardiac rhythm products, heart failure products, structural heart and aortic products, coronary and peripheral products.
Unusually-shaped ends of one or more bones where they form a joint, or an abnormally shallow angle of the bone, such as in coxa valga. A mutation in collagen or collagen-related genes (as found in certain types of Ehlers-Danlos syndrome) or other connective tissue (as found in Loeys–Dietz syndrome and Marfan syndrome) resulting in weakened ligaments/ligamentous laxity. Ligaments hold bones together at the joints. Abnormal joint proprioception (an impaired ability to locate body parts in space and/or monitor an extended joint) Hypermobility tends to run in families, suggesting a genetic basis for at least some forms. The term double jointed is often used to describe hypermobility; however, the name is a misnomer and should not be taken literally, as people with hypermobile joints do not have any extra joints, or any extra bones or parts in the joint. Symptoms are often exacerbated during pregnancy. During pregnancy, the body releases relaxin and certain hormones that alter ligament physiology, easing the stretching needed to accommodate fetal growth as well as the birthing process. The combination of hypermobility and pregnancy-related pelvic girdle during pregnancy can be debilitating. The pregnant woman with hypermobile joints may be in significant pain as muscles and joints adapt to the pregnancy. Pain makes standing or walking difficult during pregnancy, so some women who have one of these disorders find they need to use a wheelchair during pregnancy.
== Production == On 14 October 2025, it was announced via the shows official Instagram page, that casting for the fourth season was now open. Applications remained open for four weeks until closing on 6 November 2025. Ten contestants were announced on 24 April 2024. Participants include Malawitte, the Drag Race franchise's fifth cisgender female contestant. On the same day it was announced that Nicky Doll and Daphné Bürki would recur in their roles again during the season, while Loïc Prigent (who was already on the judging panel during the All Stars installment) and Anggun are joining the judging panel to take the place of Kiddy Smile.
=== Generic names === Gonadorelin is the generic name of the drug and its INNTooltip International Nonproprietary Name, BANTooltip British Approved Name, and JANTooltip Japanese Accepted Name, while gonadorelina is its DCITTooltip Denominazione Comune Italiana and gonadoréline is its DCFTooltip Dénomination Commune Française. The diacetate salt is known as gonadorelin acetate and this is its USANTooltip United States Adopted Name, BANMTooltip British Approved Name, and JANTooltip Japanese Accepted Name, while the hydrochloride salt is known as gonadorelin hydrochloride and this is its USANTooltip United States Adopted Name and BANMTooltip British Approved Name.
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.