The short version of aggregation fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-04-16. Anything still debated is marked as such rather than presented as settled.
Clinical studies of semaglutide generally measure glycated hemoglobin, fasting plasma glucose, body weight, and composite cardiovascular endpoints. The SUSTAIN program enrolled adults with type 2 diabetes, while the STEP program focused on obesity without diabetes. Administration follows a stepwise escalation schedule designed to limit gastrointestinal effects during the first weeks. Reported outcomes include mean percentage weight change, the proportion of participants reaching defined weight-loss thresholds, and rates of nausea, vomiting, and diarrhea. Long-term data on durability after treatment stops are still limited and remain a topic of ongoing research.
Semaglutide is a synthetic peptide analog of human glucagon-like peptide-1, developed by Novo Nordisk and first approved in 2017 for type 2 diabetes. It belongs to the incretin mimetic class, a group of agents that reproduce the glucose-dependent actions of endogenous GLP-1. The molecule was engineered to resist degradation by dipeptidyl peptidase-4 and to bind serum albumin, extending its half-life from minutes to roughly one week. Approval for chronic weight management followed in 2021, based on large cardiovascular and obesity outcome trials.
GLP-1 receptors are expressed on pancreatic beta cells, in the gut, and in several brain regions. Receptor activation raises cyclic AMP, enhances glucose-dependent insulin secretion, and suppresses glucagon release when blood glucose is high. Effects on gastric emptying and on hypothalamic appetite circuits reduce energy intake. Because insulin release remains glucose-dependent, the risk of hypoglycemia is low when the drug is used alone. The precise contribution of each pathway to body weight change in humans remains an area of active investigation.
Peptide degradation follows several routes. Hydrolysis cleaves the backbone at susceptible residues, oxidation targets methionine and tryptophan side chains, and aggregation produces higher-molecular-weight species that are difficult to reverse. Light exposure accelerates oxidation, which is why amber glass or opaque secondary packaging is common. Repeated freeze-thaw cycles promote aggregation and are best avoided. Stability-indicating methods detect these changes before they become visible.
Quality control for research material typically involves reversed-phase HPLC for purity and identity, mass spectrometry for molecular weight confirmation, and Karl Fischer titration for residual water content. Peptide content is often reported as the mass of actual peptide rather than total powder mass, since counterions and water contribute to the latter. A certificate of analysis should list the method used for each specification. Limits and acceptance criteria vary by supplier and by intended application.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C187H291N45O59 | Peptide backbone with a C18 fatty diacid side chain |
| Molecular weight | Approximately 4113 Da | Consistent with a 31-residue peptide plus linker |
| Appearance | White to off-white powder | Lyophilized solid; hygroscopic if left open |
| Solubility class | Sparingly soluble to soluble in water | Varies with pH and ionic strength |
| Typical analytical method | Reversed-phase HPLC with UV detection | Often paired with mass spectrometry for identity |
Storage guidance for the finished injectable product distinguishes the unused state from the in-use state. Before first use, pens are kept refrigerated between 2 and 8 degrees Celsius, protected from light, and never frozen, since freezing can disrupt the peptide or the device. After first use, label instructions in several markets permit storage at room temperature up to about 30 degrees Celsius for a limited number of days. Solid research-grade material is normally held at or below minus 20 degrees Celsius, often with desiccant, and allowed to equilibrate before opening.
Quantification and purity assessment rely on separation methods coupled to optical or mass detection. Reversed-phase high-performance liquid chromatography resolves the intact peptide from related impurities and is the standard assay technique. Size-exclusion chromatography measures aggregates, while ion-exchange chromatography separates charge variants produced by deamidation. Mass spectrometry confirms identity and detects mass shifts of a few daltons. In biological matrices, liquid chromatography with tandem mass spectrometry is often used because immunoassays can cross-react with endogenous GLP-1 or with circulating fragments.
As a peptide, semaglutide is sensitive to conditions that break amide bonds or modify side chains. Deamidation of asparagine and glutamine residues, oxidation of methionine and tryptophan, and non-covalent aggregation are the main degradation routes described in published stability work. Rate depends strongly on pH, buffer species, ionic strength, temperature and exposure to light. Formulators therefore choose a defined solution pH and often add excipients such as phosphate buffer, propylene glycol and phenol, each of which plays a separate role in pH control, tonicity or preservation.
Quality control for peptide material focuses on identity, purity, content and the profile of impurities. Common degradants include deamidated and oxidised forms, plus aggregates formed during storage or handling. Forced degradation studies under heat, light, acid and peroxide help define which conditions accelerate change and which analytical methods detect it. Limits for individual impurities are set by pharmacopoeial monographs or manufacturer specifications. How much a given impurity affects biological activity is often uncertain, and conclusions may depend on the assay used.
Solid peptide material is generally kept at reduced temperature to limit degradation. Short-term storage at 2 to 8 degrees Celsius is common, while longer archival storage at minus 20 degrees Celsius or below is typical for lyophilised powder. Vials should remain sealed and protected from light, because ultraviolet exposure can oxidise susceptible residues. Repeated freeze-thaw cycles are avoided, as they promote aggregation and loss of soluble material. Solutions are less stable than solids and are usually prepared close to the time of use.
Kalra graduated from Christian Medical College, Ludhiana. He completed his postgraduation (MD) in Medicine at Pandit Bhagwat Dayal Sharma Post Graduate Institute of Medical Sciences, Rohtak, and his fellowship (DM) in Endocrinology and Metabolism at the All India Institute of Medical Sciences, New Delhi.
Jensen "for their discoveries concerning nuclear shell structure" and Eugene Paul Wigner "for his contributions to the theory of the atomic nucleus and the elementary particles, particularly through the discovery and application of fundamental symmetry principles". 1964: American mathematician Irene Stegun completed the work which led to the publication of Handbook of Mathematical Functions, a widely used and widely cited reference work in applied mathematics. 1964: British chemist Dorothy Crowfoot Hodgkin received the Nobel Prize in Chemistry "for her determinations by X-ray techniques of the structures of important biochemical substances". 1964: Egyptian physician and medical geneticist Nemat Hashem established the first medical genetics clinic in the Arab world at Ain Shams University in Cairo. 1964: Scottish virologist June Almeida made the first identification of a human coronavirus. 1965: Sister Mary Kenneth Keller became the first American woman to receive a Ph.D. in computer science. Her thesis was titled "Inductive Inference on Computer Generated Patterns". 1966: Japanese immunologist Teruko Ishizaka, working with Kimishige Ishizaka, discovered the antibody class Immunoglobulin E (IgE). 1966: Serbian astrophysicist Mirjana Vukićević-Karabin founded the School of Astrophysics at the University of Belgrade 1966: Irish chemist Eva Philbin became the first woman president of the Institute of Chemistry of Ireland. 1967: British astrophysicist Jocelyn Bell Burnell co-discovered the first radio pulsars.
Carnation Evaporated Milk (now owned by Nestlé and licensed to Smuckers in Canada) Dairy Isle (Canada by ADL) PET Evaporated Milk (now owned by Smuckers) Magnolia evaporated milk - (now produced by Eagle Family Foods ) Viking Melk (Norway) - invented by Olav Johan Sopp in 1891, a Nestlé brand since 1897 F&N Evaporated Milk California Farms Evaporated Milk Rainbow Milk, a brand of Royal Friesland Foods Nordmilch AG (Now DMK Deutsches Milchkontor) - Germany Jerzee Evaporated Milk (purchased in 2006 from Diehl Food Products) O-AT-KA Evaporated Milk Ferdi Evaporated Milk (Malaysia) Vitalait Evaporated Milk (Senegal) Luna Evaporated Milk (Saudi Arabia) Gloria Evaporated Milk (Peru)
== Research directions == Current research and recommendations to manage severe acute malnutrition (SAM), such as kwashiorkor, in children, are largely based on expert opinions. Only one-third of the WHO guidelines for the management of SAM are based on epidemiological and clinical research. Further studies are needed to "improve treatment outcomes in the large number of children with SAM."
=== Pharmacodynamics === Pharmacodynamics refers to the biochemical and physiological effects of drugs on the body and the mechanism of the action. it answers the question, "What does the drug do to the body?" This include :
Sources: en.wikipedia.org
==== Reduction ==== Reduction of the carbonyl groups of chiral 2,5-diketopiperazine with lithium aluminium hydride (LiAlH4) cleanly gives the corresponding chiral piperazines. For example, cyclo(L-Phe-L-Phe) 1 gives the chiral piperazine (2S,5S)-dibenzylpiperazine 2.
=== Warnings and precautions === In December 2013, the FDA added warnings to the label for clobazam, that it can cause serious skin reactions, Stevens–Johnson syndrome, and toxic epidermal necrolysis, especially in the first eight weeks of treatment.
=== Legal status === In September 2022, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Zynlonta, intended for the treatment of adults with diffuse large B-cell lymphoma (DLBCL) and high-grade B-cell lymphoma (HGBL). The applicant for this medicinal product is ADC Therapeutics (NL) B.V. Loncastuximab tesirine was approved for medical use in the European Union in December 2022.
== Clinical significance == Leukotrienes, which require the FLAP protein to be synthesized, have an established pathological role in allergic and respiratory diseases. Animal and human genetic evidence suggests they may also have an important role in atherosclerosis, myocardial infarction, and stroke. The structure of FLAP provides a tool for the development of novel therapies for respiratory and cardiovascular diseases and for the design of focused experiments to probe the cell biology of FLAP and its role in leukotriene biosynthesis.
Sources: en.wikipedia.org
The modern method of embalming involves the injection of various chemical solutions into the arterial network of the body to primarily disinfect and slow the decomposition process. William Harvey, the 17th century English physician who was the first to detail the system of blood circulation, made his discoveries by injecting colored solutions into corpses. The Scottish surgeon William Hunter was the first to apply these methods to the art of embalming as part of mortuary practice. He wrote a widely read report on the appropriate methods for arterial and cavity embalming in order to preserve bodies for burial. His brother, John Hunter, applied these methods and advertised his embalming services to the general public from the mid-18th century. One of his more notorious clients was dentist Martin Van Butchell. When his wife Mary died on 14 January 1775, he had her embalmed as an attraction to draw more customers. Hunter injected the body with preservatives and color additives that gave a glow to the corpse's cheeks, replaced her eyes with glass eyes, and dressed her in a fine lace dress. The body was embedded in a layer of plaster of Paris in a glass-topped coffin. Butchell exhibited the body in the window of his home and many Londoners came to see it; however, Butchell drew criticism for the display. A rumor, possibly started by Butchell himself, claimed that his wife's marriage certificate had specified that her husband would only have control over her estate after her death for as long as her body was kept unburied.
During the Islamic Golden Age under the Abbasid Caliphate, prominent Muslim physicians preserved, systematized and developed ancient medical knowledge from across the Eurasian continent. They synthesized concepts from classical antiquity (see: Ancient Greece, Ancient Rome), Persia, Ayurveda, and China. This work laid the foundations for later advances in medieval European medicine as European physicians came into contact with Islamic authors through the Renaissance of the 12th century. Rhazes (c. 865–925), or Muhammad ibn Zakariya al-Razi, included writings about diabetes in the more than 230 books he produced in his lifetime. Avicenna (980–1037), or Ibn Sina, was a court physician to the caliphs of Baghdad and a key figure in medicine who compiled an exhaustive medical encyclopedia titled The Canon of Medicine. His account detailed the clinical features of diabetes, and termed the disease albulab ("water wheel") and zalkh el kuliah ("diarrhea of the kidneys"). He documented "the abnormal appetite and the collapse of sexual functions" and the sweet taste of diabetic urine, and further differentiated diabetes associated with emaciation from other causes of polyuria. He also elaborated on diabetic gangrene and treated diabetes using a mixture of lupine, trigonella (fenugreek), and zedoary seed. It has been noted that references to diabetes expanded in the medical texts of this period. Eknoyan and Nagy (2005) speculate that this indicates the increasing prevalence of the disease.
Click chemistry is an approach to chemical synthesis that is used to join two molecules. The application of the term, click, as a qualifier to the type of chemistry refers to an emphasis on efficiency and simplicity. To link two molecular components, each is first fitted with appropriate functional groups, such as azide and alkyne groups. These components are then "clicked" together in a process that is highly favorable and which tolerates many functional groups that might complicate other coupling processes.
Anti-centromere antibodies are associated with limited cutaneous systemic sclerosis, also known as CREST syndrome, primary biliary cirrhosis and proximal scleroderma. There are six known antigens, which are all associated with the centromere; CENP-A to CENP-F. CENP-A is a 17kDa histone H3-like protein. CENP-B is an 80kDa DNA binding protein involved in the folding of heterochromatin. CENP-C is a 140kDa protein involved in kinetochore assembly. CENP-D is a 50kDa protein of unknown function, but may be homologous to another protein involved in chromatin condensation, RCC1. CENP-E is a 312kDa protein from the kinesin motor protein family. CENP-F is a 367kDa protein from the nuclear matrix that associates with the kinetochore in late G2 phase during mitosis. CENP-A, B and C antibodies are most commonly found (16–42% of systemic sclerosis) and are associated with Raynaud's phenomenon, telangiectasias, lung involvement and early onset in systemic sclerosis. Anti-centromere antibodies are found in approximately 60% of patients with limited systemic scleroderma and in 15% of those with the diffuse form of scleroderma. The specificity of this test is >98%. Thus, a positive anti-centromere antibody finding is strongly suggestive of limited systemic scleroderma. Anti-centromere antibodies present early in the course of disease and are notably predictive of limited cutaneous involvement and a decreased likelihood of aggressive internal organ involvement, such as fibrosis in the lungs.
Railway transport in Malaysia is state-run, and spans some 2,783 kilometres (1,729 mi). As of 2016, Malaysia has the world's 26th-largest road network, with some 238,823 kilometres (148,398 mi) of roads. Malaysia's inland waterways are the world's 22nd-longest, and total 7,200 km (4,474 mi). Among Malaysia's 114 airports, the busiest one is Kuala Lumpur International Airport (KLIA), located in the Sepang District; it is also the 12th-busiest airport in Asia. Among the seven federal ports, the major one is Port Klang, which is the 13th-busiest container port. Malaysia's flag carrier is Malaysia Airlines, providing international and domestic air services. Malaysia's telecommunications network is second only to Singapore's in Southeast Asia, with 4.7 million fixed-line subscribers and more than 30 million cellular subscribers. There are 200 industrial parks along with specialised parks such as Technology Park Malaysia and Kulim Hi-Tech Park. Fresh water is available to over 95% of the population, with groundwater accounting for 90% of the freshwater resources. Although rural areas have been the focus of great development, they still lag behind areas such as the West Coast of Peninsular Malaysia. The telecommunication network, although strong in urban areas, is less available to the rural population. Malaysia's energy infrastructure sector is largely dominated by Tenaga Nasional, the largest electric utility company in Southeast Asia. Customers in Peninsular Malaysia are connected to electricity through the National Grid.
Sources: en.wikipedia.org
It is given either as a once-weekly subcutaneous injection or as an oral tablet taken once daily. The two forms use different absorption strategies, so they are not interchangeable on a milligram-for-milligram basis.
Structural modifications, including a fatty acid side chain and non-natural amino acid substitutions, slow enzymatic breakdown and promote albumin binding. These changes support once-weekly dosing rather than twice-daily administration.
The pathways involving insulin, glucagon, gastric emptying, and appetite signaling are well described. How much each pathway contributes to weight reduction in a given person is not fully established.
Sealed, protected from light, and refrigerated at two to eight degrees Celsius for most research material. Desiccated storage limits moisture uptake. Allow the vial to reach room temperature before opening to prevent condensation.