albumin binding 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 2025-09-23 and is reviewed periodically as new material appears.
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.
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.
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 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 |
Development began in the early 2010s with the goal of extending GLP-1 activity beyond the brief window achieved by native peptide infusion. The earliest approved formulation was a subcutaneous injection given once weekly. A later oral tablet pairs the peptide with an absorption enhancer, sodium N-(8-[2-hydroxybenzoyl] amino) caprylate, usually shortened to SNAC. That carrier lowers local pH and helps the peptide cross gastric tissue. Both routes deliver the same active molecule.
Semaglutide is a synthetic peptide analog of human glucagon-like peptide-1, a gut hormone released after meals. Its backbone retains the GLP-1 sequence but incorporates two substitutions that slow enzymatic breakdown by dipeptidyl peptidase-4. A short polyethylene glycol linker and a C18 fatty diacid are attached to the peptide chain, allowing the molecule to bind serum albumin and remain in circulation far longer than the native hormone. The result is a circulating half-life measured in days rather than the minutes typical of endogenous GLP-1.
Receptor activation occurs at GLP-1 receptors distributed across pancreatic islets, the hypothalamus, and the gastrointestinal tract. Binding triggers G protein signaling that raises cyclic AMP and enhances glucose-dependent insulin release. Because the effect depends on prevailing glucose levels, insulin secretion does not rise when blood sugar is already low. Signaling in the brain and gut also influences appetite and gastric emptying, which is why the compound appears in both metabolic and weight-related research literature.
Receptor activation raises intracellular cyclic AMP through Gs coupling, which promotes glucose-dependent insulin release and suppresses glucagon secretion when blood glucose is elevated. Effects outside the pancreas include slower gastric emptying and altered appetite signalling in the hypothalamus and hindbrain. The relative contribution of each tissue to overall metabolic outcomes remains an area of active investigation. Central mechanisms in particular are inferred mainly from animal models and indirect human measures rather than direct observation.
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.
Material described as research-grade is not necessarily manufactured to pharmaceutical standards, and purity figures depend on the method used to obtain them. A certificate of analysis states the measured purity, the analytical technique, and the batch identifier, but the underlying data are not always included. Independent testing by a second laboratory is a common way to confirm identity and purity. Uncertainties remain about how storage history affects long-term stability, and about how well results from one laboratory transfer to another. Documentation of handling conditions supports comparison between batches.
Peptides are sensitive to temperature, light, oxygen, and repeated freeze-thaw cycles. Semaglutide in dry form is generally held at refrigerated temperatures, while reconstituted solutions require a defined short-term storage window. Vials should be kept in secondary packaging to limit photodegradation, and exposure to alkaline conditions is avoided because it accelerates chemical degradation. Adsorption to glass and some plastics can reduce the measured concentration of dilute solutions, so low-binding polypropylene containers are preferred for analytical work. Each transfer step introduces a small risk of contamination, and closed handling practices reduce that risk.
=== Musculoskeletal examination of congenital muscular dystrophies === Muscle fibrosis and Joint contractures or fixed deformities are cardinal clinical signs of congenital muscular dystrophies. Muscle fibrosis and shortening eventually lead to joint contractures or fixed deformities. They are important to the diagnosis of CMD. However, some patients initially present with joint laxity. Joint deformities can occur in the extremities and spine. Severe deformities can result in joint dislocation and walking difficulties or gait abnormalities. However, the specific pattern of muscle involvement in each of the CMD subtypes is not fully elucidated. A recent review identified CMD subtype-specific clinical patterns of muscle and Joint involvement which could be of help to the differential diagnosis of CMD subtypes. This was especially true for Merosin-deficient congenital muscular dystrophy (MDC1A) or LAMA2-related CMD subtype. Nonetheless, these muscle and Joint patterns of involvement have to be correlated with other clinical signs, neuro-imaging reports, muscle biopsy immune-staining and molecular or genetic analysis results, whenever available. This comprehensive approach is critical for the correct and timely diagnosis of CMDs.
Most cell types in loose connective tissue are transient wandering cells that migrate from local blood vessels in response to specific stimuli. Loose connective tissue, therefore, is a site of inflammatory and immune reactions. In areas of the body where foreign substances are continually present, large populations of immune cells are maintained. For example, the lamina propria, the loose connective tissue of mucous membranes, such as those of the respiratory and alimentary systems, contains large numbers of these cells.
=== Pancreatic === Although most of the glucokinase in the body is in the liver, smaller amounts in the beta and alpha cells of the pancreas, certain hypothalamic neurons, and specific cells (enterocytes) of the gut play an increasingly appreciated role in regulation of carbohydrate metabolism. In the context of glucokinase function, these cell types are collectively referred to as neuroendocrine tissues, and they share some aspects of glucokinase regulation and function, especially the common neuroendocrine promoter. Of the neuroendocrine cells, the beta cells of the pancreatic islets are the most-studied and best-understood. It is likely that many of the regulatory relationships discovered in the beta cells will also exist in the other neuroendocrine tissues with glucokinase.
Deadlift – 400 kg (882 lb) (2005 Pojedynek Gigantów) Keg drop Deadlift – 295–350 kg (650–771 lb) x 6 lifts in 33.89 seconds (2005 World's Strongest Man) Keg drop Squat – 265–340 kg (584–750 lb) x 7 reps in 21.28 seconds (2007 World's Strongest Man - Group 4) Keg drop Squat – 260–360 kg (573–794 lb) x 7 reps in 27.53 seconds (2005 World's Strongest Man) (former world record) Log lift – 172 kg (379 lb) (2005 Met-Rx Grand Prix) Log lift (for reps) – 130 kg (287 lb) x 14 reps (2006 Moscow Grand Prix) Axle press (for reps) – 140 kg (309 lb) x 11 reps (2006 WSMC Poland) (World Record) Apollon wheel press – 166 kg (366 lb) x 4 reps (2004 Arnold Strongman Classic) Viking press – 150 kg (331 lb) x 12 reps (2007 Mohegan Sun Grand Prix) Kettlebell press – 80 kg (176 lb) x 8 reps (2009 Globe's Strongest Man) Atlas Stones – 5 stones weighing 115–155 kg (254–342 lb) on tall platforms in 21.09 seconds (2006 Strongman Super Series Moscow Grand Prix) (World Record) Ding carry – 160 kg (353 lb) for 90 metres (2005 World's Strongest Man) (World Record) Asia Stone / shield carry – 175 kg (386 lb) for 127.4 metres (2002 World's Strongest Man) (World Record) Africa Stone carry – 175 kg (386 lb) for 110 metres (2000 World's Strongest Man - Group 5) (World Record) Block carry – 180 kg (397 lb) for 80 metre course in 41.32 seconds (2002 Europe's Strongest Man) (World Record) Fridge carry (super yoke) – 410 kg (904 lb) for 20 metres in 15.29 seconds (2005 World's Strongest Man) Timber carry – 392 kg (864 lb) (40' ramp) in 22.93 seconds (Raw grip) (2006 Arnold Strongman Classic) Wheelbarrow carry (no straps) – 300 kg (661 lb) (25m course) in 15.50 seconds (2003 IFSA Finland Grand Prix) (World Record) Farmer's walk (no straps) – 150 kg (331 lb) per each hand for 60m course in 19.90 seconds (2006 Strongman Super Series Poland Grand Prix) (World Record) Farmer's walk (no straps) – 137.5 kg (303 lb) per each hand for 70m course in 22.48 seconds (2003 Strongman Super Series Finland Grand Prix) (World Record) Super Yoke – 360 kg (794 lb) for 20 meters in 7.66 seconds (2006 World Strongman Cup Federation, Poland) (World Record) Medicine Ball Toss – 23 kg (51 lb) for 4.88 meters (2004 Arnold Strongman Classic) Power Stairs – (225 kg (496 lb) total of 14 steps) – 40.94 seconds (2008 World's Strongest Man) (World Record) Power Stairs – (230 kg (507 lb) total of 23 shallow steps) – 26.33 seconds (2006 World's Strongest Man) (World Record) Power Stairs – (200 kg (441 lb), 230 kg (507 lb) & 250 kg (551 lb) total of 15 high steps) – 31.22 seconds (2004 Europe's Strongest Man) (World Record) Power Stairs – (225 kg (496 lb), 250 kg (551 lb) & 275 kg (606 lb) total of 15 steps) – 28.56 seconds (2005 Nautilus Grand Prix) (World Record) Tyre Flip – 380 kg (838 lb) Tyre x 8 flips - 20.81 seconds (2004 Holland Champions Trophy) and 400 kg (882 lb) Tyre x 8 flips - 22.87 seconds (2006 Moscow Grand Prix) (former world records) Flip & drag – 400 kg (882 lb) tyre x 4 flips and 300 kg (661 lb) anchor & chain drag for 30 meters – 39.01 seconds (2002 World's Strongest Man) (world record) Conan's wheel (Basque circle) – 360 kg (794 lb) 765° rotation (2006 World Strongman Cup Russia) (World Record) Conan's wheel (Basque circle) – 317.5 kg (700 lb) 1,203° rotation (2003 Strongman Super Series Holland Grand Prix) (World Record) Conan's wheel (Basque circle) – 300 kg (661 lb) 1,440° rotation (2002 World's Strongest Man - Group 5) (former world record) Train pull – 16,000 kg (35,274 lb) for 25 meter course in 30.78 seconds (2003 World's Strongest Man) (World Record) Truck pull – 24,000 kg (52,911 lb) for 20 meter course in 26.05 seconds (2003 IFSA Strongman World Record Breakers) (World Record) Plane pull – 40,000 kg (88,185 lb) for 25 meter course in 36.67 seconds (2008 World's Strongest Man) (World Record) During training: (Self-claims)
Sources: en.wikipedia.org
=== Sequence-based methods === Prime, NetMHCpan, MHCnuggets, MHCflurry, DeepNeo, and BigMHC are among the most popular methods to predict peptide-MHC immunogenicity from protein amino acid sequences. They essentially parse the protein sequences as text data, using 1-dimensional convolutional neural networks, recurrent neural networks, or Transformer models.
=== History === Fu, Jia-Chen; King, Michelle; Klein, Jakob, eds. (2025). Modern Chinese Foodways. MIT Press. ISBN 9780262381642. Chang, Kwang-chih (1977). Food in Chinese Culture: Anthropological and Historical Perspectives. New Haven: Yale University Press. ISBN 0300019386. David R. Knechtges, "A Literary Feast: Food in Early Chinese Literature," Journal of the American Oriental Society 106.1 (1986): 49–63. Newman, Jacqueline M. (2004). Food Culture in China. Westport, Conn.: Greenwood Press. ISBN 0313325812. Roberts, J. A. G. (2002). China to Chinatown: Chinese Food in the West. London: Reaktion. ISBN 1861891334. Sterckx, Roel. Food, Sacrifice, and Sagehood in Early China. New York: Cambridge University Press, 2011 (2015). Sterckx, Roel. Chinese Thought. From Confucius to Cook Ding. London: Penguin, 2019. Swislocki, Mark (2009). Culinary Nostalgia: Regional Food Culture and the Urban Experience in Shanghai. Stanford, CA: Stanford University Press. ISBN 9780804760126. Waley-Cohen, Joanna (2007). "Celebrated Cooks of China's Past". Flavor & Fortune. 14 (4): 5–7, 24. Archived from the original on 2 April 2015. Endymion Wilkinson, "Chinese Culinary History (Feature Review)," China Review International 8.2 (Fall 2001): 285–302. Wilkinson, Endymion (2022). Chinese History: A New Manual. Cambridge, MA: Harvard University Press. ISBN 978-0674260184. Wu, David Y. H.; Cheung, Sidney C. H. (2002). The Globalization of Chinese Food. Richmond, Surrey: Curzon. ISBN 0700714030.
== In plants == The light reactions of photosynthesis generate ATP by the action of chemiosmosis. The photons in sunlight are received by the antenna complex of Photosystem II, which excites electrons to a higher energy level. These electrons travel down an electron transport chain, causing protons to be actively pumped across the thylakoid membrane into the thylakoid lumen. These protons then flow down their electrochemical potential gradient through an enzyme called ATP-synthase, creating ATP by the phosphorylation of ADP to ATP. The electrons from the initial light reaction reach Photosystem I, then are raised to a higher energy level by light energy and then received by an electron acceptor and reduce NADP+ to NADPH. The electrons lost from Photosystem II get replaced by the oxidation of water, which is "split" into protons and oxygen by the oxygen-evolving complex (OEC, also known as WOC, or the water-oxidizing complex). To generate one molecule of diatomic oxygen, 10 photons must be absorbed by Photosystems I and II, four electrons must move through the two photosystems, and 2 NADPH are generated (later used for carbon dioxide fixation in the Calvin Cycle).
=== Breastfeeding and the prosthetic breast === The breasts of a woman are apocrine glands that produce breastmilk with which to feed an infant child. A woman with implanted prosthetic breasts can breastfeed an infant, yet the breast implants can interfere with the breastfeeding function, especially in the case of a woman whose breast augmentation surgery accidentally cut into the nipple-areola complex (NAC) and might either have damaged the lactiferous ducts or damaged the nerves that serve the nipple-areola complex.
For example, the values for glucose, sucrose, and starch are 15.57, 16.48 and 17.48 kilojoules per gram (3.72, 3.94 and 4.18 kcal/g) respectively. The differing energy density of foods (fat, alcohols, carbohydrates and proteins) lies mainly in their varying proportions of carbon, hydrogen, and oxygen atoms. Carbohydrates that are not easily absorbed, such as fibre, or lactose in lactose-intolerant individuals, contribute less food energy. Polyols (including sugar alcohols) and organic acids contribute 10 kJ/g (2.4 kcal/g) and 13 kJ/g (3.1 kcal/g) respectively. The energy contents of a food or meal can be approximated by adding the energy contents of its components, though the entire amount of calories calculated may not be absorbed during digestion.
Sources: en.wikipedia.org
A member of the People's Assembly (Arabic: عضو مجلس الشعب) refers to members of the Parliament of Syria. Historically, members of the Syrian parliament have been referred to in Arabic as nā'ib (نائب, "deputy"), plural nuwāb (نواب), a usage rooted in the legislature's earlier incarnation as the Chamber of Deputies (1932–1963). Following the parliament's reconstitution as the People's Assembly under Ba'athist rule in 1971, members came to be more commonly styled "member of the People's Assembly" in official and state-media usage. Nonetheless, "deputy" has persisted as a recognised designation, including in coverage of the current transitional-era Assembly formed after 2024.
The heart is an organ located in the thoracic cavity between the lungs and slightly to the left. It is surrounded by the pericardium, which holds it in place in the mediastinum and serves to protect it from blunt trauma, infection and help lubricate the movement of the heart via pericardial fluid. The heart works by pumping blood around the body allowing oxygen, nutrients, waste, hormones and white blood cells to be transported.
=== Presbyopia === In 2025, the U.S. Food and Drug Administration (FDA) approved aceclidine 1.44 % ophthalmic solution (Vizz) for the topical treatment of presbyopia. The treatment involves a once-daily application to constrict the pupil, creating a pinhole effect that increases the depth of focus and improves near vision. Data from the Clarity 1 and 2 clinical trials showed that the administration of aceclidine resulted in a statistically significant improvement in near visual acuity within approximately 30 minutes, with a duration of effect of up to 8–10 hours. Distance vision was not significantly affected due to the drug's limited action on the ciliary muscle. No serious adverse events were reported in the trials. Common side effects included transient ocular irritation, mild headache, and reduced vision in low-light conditions. Aceclidine became the second pharmacological agent approved for presbyopia in the U.S., following a pilocarpine-based product approved in 2021.
== Further reading == Walker, John (November 21, 2007). "RPS Exclusive: Gabe Newell Interview". Rock, Paper, Shotgun. Bramwell, Tom (August 29, 2007). "Valve's Gabe Newell". Eurogamer. Gamer Network. Keighley, Geoff (November 12, 2004). "The Final Hours of Half-Life 2". GameSpot. CBS Interactive. Psycho_byte (June 26, 2003). "An interview with Gabe Newell". HL2Central. Game Central Network. Archived from the original on August 11, 2018. Retrieved February 9, 2016. Peterson, Andrea (January 3, 2014). "Gabe Newell on what makes Valve tick". The Washington Post.
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.
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.