A practical reference on Freeze-thaw: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-01-17. Anything still debated is marked as such rather than presented as settled.
Serum protein binding dominates the pharmacokinetic profile. The attached chain associates strongly with albumin, shielding the peptide from enzymatic attack and slowing filtration by the kidney. This interaction extends the circulation half-life to roughly one week in humans, which supports weekly administration intervals. An oral version pairs the peptide with an absorption enhancer that transiently alters gastric epithelium, permitting limited uptake; bioavailability by that route is substantially lower than by injection.
Semaglutide belongs to the glucagon-like peptide-1 receptor agonist class, a group of synthetic peptides that imitate an incretin hormone released by intestinal L cells after food intake. Native GLP-1 circulates for only a few minutes because dipeptidyl peptidase-4 cleaves it rapidly. The hormone acts on pancreatic islets, the gastrointestinal tract, and several brain regions. Because the natural peptide is short-lived, development work concentrated on analogues that keep receptor activity while resisting enzymatic breakdown and renal clearance.
Semaglutide is a synthetic peptide analogue of glucagon-like peptide-1, a gut hormone released by intestinal L cells after food intake. The natural hormone acts on pancreatic and central receptors but is degraded within minutes by dipeptidyl peptidase-4 and other peptidases. Semaglutide belongs to the class of long-acting GLP-1 receptor agonists, a group distinguished by structural changes that slow breakdown and extend circulation time. Its development followed earlier short-acting analogues and reflects a general strategy in peptide drug design: preserve receptor activity while blocking proteolytic clearance.
Three structural changes define the molecule. At position 8 an alpha-aminoisobutyric acid residue replaces alanine, which blocks dipeptidyl peptidase-4 cleavage. At position 34 arginine replaces lysine, and at position 26 a lysine carries a C18 fatty diacid attached through a short linker. The fatty chain binds serum albumin, and this albumin association reduces renal filtration and enzymatic attack. The unchanged backbone retains the receptor contacts that produce signalling. The free base has the formula C187H291N45O59 and a molecular weight near 4114 daltons.
Receptor activation follows the canonical Gs pathway: binding increases intracellular cyclic AMP, which promotes protein kinase A activity. In pancreatic beta cells this amplifies glucose-dependent insulin release, so secretion rises when blood glucose is high and changes little when it is low. The same signalling suppresses glucagon release from alpha cells and slows gastric emptying. Receptors in the hypothalamus and brainstem are thought to contribute to reduced appetite and lower energy intake. Which of these effects dominates clinical outcomes remains an area of active study.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide, GLP-1 receptor agonist | 31 amino acid residues |
| Molecular formula | C187H291N45O59 | free peptide, no counter-ion |
| Approximate mass | 4114 Da | matches theoretical value |
| Receptor target | Glucagon-like peptide-1 receptor | Gs-coupled, cyclic AMP pathway |
| Circulation half-life | About one week in humans | extended by albumin association |
The primary target is the GLP-1 receptor, a class B G protein-coupled receptor expressed on pancreatic beta cells, in the gut, and in several brain regions. Receptor activation raises intracellular cyclic AMP, which potentiates glucose-dependent insulin secretion and lowers glucagon release when blood glucose is elevated. Signalling in the hypothalamus and brainstem is associated with reduced appetite and slower gastric emptying. Because the insulinotropic effect depends on prevailing glucose levels, the hypoglycaemic risk of the peptide alone is described as low in most study settings. The relative contribution of peripheral and central actions remains an active research question.
Large randomised trials in adults with type 2 diabetes and in adults with obesity have reported reductions in body weight and improvements in several cardiovascular risk markers. One outcome trial found a lower incidence of major adverse cardiovascular events in participants with diabetes and established cardiovascular disease. Gastrointestinal effects such as nausea and vomiting are the most frequently reported adverse events and often diminish over time. Changes in lean body mass during weight loss are an area of ongoing investigation. Effects in adolescents and in pregnancy are less well characterised, and current labelling advises against use during pregnancy.
Semaglutide is a synthetic peptide analogue of glucagon-like peptide-1, a gut hormone released after nutrient intake. The molecule contains 31 amino acid residues and differs from the native sequence at several positions. A non-natural residue at position eight resists the enzyme that normally truncates the hormone, while a lysine-linked fatty diacid side chain promotes binding to serum albumin. These two modifications extend the circulating half-life from minutes to roughly one week. The peptide is produced by solid-phase synthesis followed by selective acylation, and its identity and purity are confirmed by spectrometric and chromatographic techniques.
Lyophilised material appears as a white to off-white cake or powder that is hygroscopic, and containers are usually equilibrated to room temperature before opening to limit condensation. Dissolution is performed in water, phosphate-buffered saline, or a mildly alkaline buffer, since solubility rises above neutral pH. Gentle inversion or low-speed mixing is preferred, because vigorous vortexing can promote surface denaturation and aggregation. Complete dissolution may require several minutes, and brief sonication is sometimes applied. Passing the solution through a 0.22 micrometre membrane removes particulates but does not by itself sterilise the liquid.
Storage at minus 20 degrees Celsius or lower in a desiccated container preserves the peptide for extended periods, while working solutions are commonly held at two to eight degrees Celsius for short intervals. Light exposure and repeated freeze-thaw cycles accelerate degradation, so dividing material into single-use aliquots is generally recommended. Adsorption to glass and plastic surfaces can lower the measured concentration of dilute solutions, particularly below one milligram per millilitre. The degradation routes most often reported for GLP-1 analogues are deamidation, methionine oxidation, and backbone hydrolysis. Relative rates under specific conditions are frequently described only for individual formulations.
Reverse-phase high-performance liquid chromatography with ultraviolet detection near 214 or 280 nanometres is widely used to assess purity and to resolve related impurities. Liquid chromatography coupled to mass spectrometry confirms identity through the protonated molecular ion and fragment ions formed in tandem experiments. Capillary electrophoresis and peptide mapping after enzymatic digestion supply complementary information on charge variants and modification sites. Circular dichroism and nuclear magnetic resonance can report on secondary structure in solution. Absolute quantification usually depends on an external standard, and reported purity depends on the detection wavelength and integration parameters chosen.
Genes express their functional effect through the production of proteins, which are molecules responsible for most functions in the cell. Proteins are made up of one or more polypeptide chains, each composed of a sequence of amino acids. The DNA sequence of a gene is used to produce a specific amino acid sequence. This process begins with the production of an RNA molecule with a sequence matching the gene's DNA sequence, a process called transcription. This messenger RNA molecule then serves to produce a corresponding amino acid sequence through a process called translation. Each group of three nucleotides in the sequence, called a codon, corresponds either to one of the twenty possible amino acids in a protein or an instruction to end the amino acid sequence; this correspondence is called the genetic code. The flow of information is unidirectional: information is transferred from nucleotide sequences into the amino acid sequence of proteins, but it never transfers from protein back into the sequence of DNA—a phenomenon Francis Crick called the central dogma of molecular biology. The specific sequence of amino acids results in a unique three-dimensional structure for that protein, and the three-dimensional structures of proteins are related to their functions. Some are simple structural molecules, like the fibers formed by the protein collagen. Proteins can bind to other proteins and simple molecules, sometimes acting as enzymes by facilitating chemical reactions within the bound molecules (without changing the structure of the protein itself).
The LCD panel is designed for medical equipment and professional video equipment. On October 25, 2012, LG Electronics began selling the first flat panel Ultra HD display in the United States with a resolution of 3840 × 2160. The LG 84LM9600 is an 84 in (210 cm) flat panel LED-backlit LCD with a price of US$19,999 though the retail store was selling it for US$16,999. On November 29, 2012, Sony announced the 4K Ultra HD Video Player—a hard disk server preloaded with ten 4K movies and several 4K video clips that they planned to include with the Sony XBR-84X900. The preloaded 4K movies are The Amazing Spider-Man, Total Recall (2012), The Karate Kid (2010), Salt, Battle: Los Angeles, The Other Guys, Bad Teacher, That's My Boy, Taxi Driver, and The Bridge on the River Kwai. Additional 4K movies and 4K video clips will be offered for the 4K Ultra HD Video Player in the future. On November 30, 2012, Red Digital Cinema Camera Company announced that they were taking pre-orders for the US$1,450 REDRAY 4K Cinema Player, which can output 4K resolution to a single 4K display or to four 1080p displays arranged in any configuration via four HDMI 1.4 connections. Video output can be DCI 4K (4096 × 2160), 4K Ultra HD, 1080p, and 720p at frame rates of up to 60 fps with a color depth of up to 12 bpc with 4:2:2 chroma subsampling. Audio output can be up to 7.1 channels. Content is distributed online using the ODEMAX video service. External storage can be connected using eSATA, Ethernet, USB, or a Secure Digital memory card.
Allyn Taylor International Prize in Medicine for Diabetes, Toronto, Canada (2002) Manpei Suzuki International Prize for Top Diabetes Researcher Worldwide (Inaugural Recipient), Tokyo, Japan (2009) Hans Falk Memorial Lecture, National Institute of Environmental Health Science (2009) Presidential Lecture, Memorial Sloan Kettering Cancer Institute, New York (2010) Alpha Omega Alpha Visiting Professor, Columbia University Medical School, New York, NY (2010) Frontiers in Science Award, American Association of Clinical Endocrinologists (2010) Cockrell Foundation Award in Basic and Clinical Research, Houston, TX (2010) Distinguished Leader in Insulin Resistance, World Congress of Insulin Resistance in Diabetes and Cardiovascular Disease, Los Angeles, CA (2010) David Murdock Dole Honorary Lecture, Mayo Clinic-Karolinska, Nobel Forum, Stockholm, Sweden (2011) Wallace H. Coulter Award, American Association of Clinical Chemistry (2013) Helmholtz Diabetes Research Lifetime Achievement Award, Munich, Germany (2013) Honorary Adjunct Member, Max Planck Institute, Cologne, Germany (2014) Ipsen Foundation Prize in Endocrine Regulation (2015) Harold Hamm Prize in Diabetes (2015) Wolf Prize in Medicine, Jerusalem, Israel (2016)
Sources: en.wikipedia.org
Examples of landmark, and frequently controversial judgments, include Van Gend en Loos (holding EU law to created a new legal order, and citizens could sue for treaty rights), Mangold v Helm (establishing equality as a general principle of EU law), and Kadi v Commission (confirming international law had to conform with basic principles of EU law). Until 2016, there was the European Union Civil Service Tribunal, which dealt with EU institutions' staff issues.
===== Daniela Carneiro ===== In the same month Minister of Tourism Daniela Carneiro came under scrutiny for her association with individuals believed to command militias in Rio de Janeiro. Carneiro, a member of the Brazil Union party, had been included by the Lula government in the Ministry of Tourism in order to increase its alliance with parties of different political positions. According to a report by Veja, Daniela, the most voted federal deputy in Rio de Janeiro in 2022, was introduced to Lula by Washington Quaquá, coordinator of Lula's campaign in Rio, and was also chosen for other characteristics considered important for the PT: being a woman and evangelical. After the appointment of Daniela, previously known as Daniela do Waguinho, press outlets began publishing a series of reports showing involvement of Carneiro's political group with militias in the Baixada Fluminense, which had also previously shown involvement and links with other politicians from right-wing parties. On 3 January, g1 published a 2018 photo of Daniela alongside Juracy Alves Prudêncio, better known as Jura, a former military police sergeant identified as the leader of a militia responsible for killings in the Baixada Fluminense. Juracy appears in videos working as a campaign worker for her. He was sentenced to 26 years in prison for murder, moved to the semi-open prison regime in 2017, and went to work at the city hall of Belford Roxo, where the mayor was Wagner dos Santos Carneiro, known as Waguinho, Daniela's husband.
=== Batten disease === Milasen is a novel individualized therapeutic agent that was designed and approved by the FDA for the treatment of Batten disease. This therapy serves as an example of personalized medicine. In 2019, a report was published detailing the development of milasen, an antisense oligonucleotide drug for Batten disease, under an expanded-access investigational clinical protocol authorized by the Food and Drug Administration (FDA). Milasen "itself remains an investigational drug, and it is not suited for the treatment of other patients with Batten's disease" because it was customized for a single patient's specific mutation. However it is an example of individualized genomic medicine therapeutical intervention.
17α-OHP is the parent compound of a class of progestins referred to as the 17α-hydroxyprogesterone derivatives. Among others, this class of drugs includes chlormadinone acetate, cyproterone acetate, hydroxyprogesterone caproate, medroxyprogesterone acetate, and megestrol acetate.
Sources: en.wikipedia.org
=== Ischemic fasciitis === Ischemic fasciitis (IF) is a benign tumor in the class of fibroblastic and myofibroblastic tumors that, like pressure ulcers, may develop in elderly, bed-ridden individuals. These tumors commonly form in the subcutaneous tissues (i.e. lower most tissue layer of the skin) that overlie bony protuberances such as those in or around the hip, shoulder, greater trochanter of the femur, iliac crest, lumbar region, or scapular region. IF tumors differ from pressure ulcers in that they typically do not have extensive ulcerations of the skin and on histopathological microscopic analysis lack evidence of acute inflammation as determined by the presence of various types of white blood cells. These tumors are commonly treated by surgical removal.
== Early life == Rosanna Jeanne Reardon was born on June 8, 1985, in Seattle, Washington, where she was raised alongside her younger sister Molly Lu. She is of Italian, Croatian, German, and Irish ancestry. She was baptized Catholic. Throughout her childhood, she was known by friends and family as a "nerdy", "awkward" kid, and she struggled with dyslexia and ADHD in school. She originally wanted to become an actress, and after attending West Seattle High School and Pacific Lutheran University, she moved to Los Angeles to pursue acting. Prior to her YouTube career, Pansino worked as a teacher in China and as a Methodist church secretary. Pansino's interest in cooking was inspired by her father and grandmother, and she stated in 2014 that "...baking has always been a hobby of mine. I have always loved being creative with my food and making themed sweets for my friends."
Environmental vegetarianism is based on the concern that the production of meat and animal products for mass consumption, especially through factory farming, is environmentally unsustainable. According to a 2006 United Nations initiative, the livestock industry is one of the largest contributors to environmental degradation worldwide, and modern practices of raising animals for food contribute on a "massive scale" to air and water pollution, land degradation, climate change, and loss of biodiversity. The initiative concluded that "the livestock sector emerges as one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global." In addition, animal agriculture is a large source of greenhouse gases. According to a 2006 report it is responsible for 18% of the world's greenhouse gas emissions as estimated in 100-year CO2 equivalents. Livestock sources (including enteric fermentation and manure) account for about 3.1 percent of US anthropogenic GHG emissions expressed as carbon dioxide equivalents. This EPA estimate is based on methodologies agreed to by the Conference of Parties of the UNFCCC, with 100-year global warming potentials from the IPCC Second Assessment Report used in estimating GHG emissions as carbon dioxide equivalents. Meat produced in a laboratory (called in vitro meat) may be more environmentally sustainable than regularly produced meat. Reactions of vegetarians vary.
Sources: en.wikipedia.org
It is a synthetic peptide of 31 amino acids, built to resemble the natural incretin hormone GLP-1. Because of its size and composition it is handled analytically like other therapeutic peptides, using chromatographic and mass spectrometric methods rather than the techniques typical of small organic drugs.
The substitution at position 8 removes the site recognised by dipeptidyl peptidase-4, the enzyme that destroys the native hormone within minutes. The linked lipophilic chain then binds circulating albumin, which further limits access by degradative enzymes and reduces renal loss. Together these features lengthen the effective circulation time considerably.
It acts at the glucagon-like peptide-1 receptor, a G protein-coupled receptor that signals mainly through cyclic AMP. Activation is glucose dependent, meaning insulin release is stimulated more strongly when blood glucose is already elevated. Other tissues carrying the same receptor respond as well, which explains effects beyond glucose control.
Native GLP-1 is a short-lived peptide cleared within one to two minutes by dipeptidyl peptidase-4 and related enzymes. Semaglutide keeps the receptor-binding backbone but adds substitutions and a lipid chain. These changes block the main cleavage site and allow reversible albumin binding, extending the half-life to roughly 165 hours.