Complications of Gastric Surgery
Stephen M. Cohn, Matthew O. Dolich in Complications in Surgery and Trauma, 2014
Gastric surgery inherently has adverse effects on GI motility. The stomach functions to receive and store food, to mix it with gastric juice and begin the process of digestion, and to propel the prepared chyme into the duodenum at a rate optimal for digestion and absorption by the small intestine. The proximal stomach is capable of sustained alteration in tension via two vagally mediated reflexes: accommodation and receptive relaxation. Receptive relaxation refers to the anticipatory relaxation of the proximal stomach to accept a food bolus from the esophagus. Accommodation describes the stomach’s ability to adapt to large changes in volume with only minimal increases in intragastric pressure. If accommodation is impaired, proximal gastric tone increases markedly during distension, and this increase leads to increased intragastric pressure and rapid emptying of liquids. Control of gastric emptying of solids is a function of the distal stomach. Solids are retained in the distal stomach, where they are mixed with gastric juice and broken down to particles before they are allowed to pass into the duodenum.
The Risks of Silver Nanoparticles to the Human Body
Huiliang Cao in Silver Nanoparticles for Antibacterial Devices, 2017
Nanosilver can also enter the human body by gastrointestinal absorption. Nanoparticles are used as ‘food contact substances’ and thus may come in contact with drinking water (e.g. nanosilver being present in various water filters and purifiers). NS present in inhaled air may be dammed by ciliated epithelium in airways and absorbed in the mucosa of airways. During the process of cleansing of the ciliated epithelium the mucus containing absorbed NS can be swallowed. Nanosilver is unstable to oxidation and can release ions through gradual reaction with dioxygen and protons. Gastric juice contains hydrochloric acid that is responsible for its acidic pH and accelerates this process. Silver ions generated in the digestive tract can enter the bloodstream through ion or nutrient uptake channels. Both microparticles and nanoparticles can be taken up in the gut via endocytosis by M-cells in Peyer’s patches. Once nanosilver enters the bloodstream, it is distributed throughout the body (Liu et al. 2012).
For The Want of a Nail … Trace Elements in Health and Disease
Owen M. Rennert, Wai-Yee Chan in Metabolism of Trace Metals in Man, 2017
Iron is found in three chemical states in the crust of the earth. As Fe° it is the metallic iron familiar to all of us. Metallic iron in the presence of oxygen and water is gradually converted to “ferric hydroxide”, Fe(OH)3 This is the familiar particulate rust of automobile radiators and chemically is identical to the “rust” that accumulates in iron-overloaded organs described above. Iron exists primarily in the more stable Fe3+ oxidation state. Salts are formed with many anions. These are soluble, but only under extremely acid conditions. The neutralization of acidic ferric salts by the addition of base results in the total precipitation of ferric hydroxide. The pH of gastric juice is about 2, while the contents of the small intestine, where the primary absorption of metals takes place, has a pH of 6.5 to 7.0. Under these conditions, the maximum solubility of ferric iron is 10-17M. The insolubility of ferric ion is in contrast with the much greater solubility of reduced ferrous iron, Fe2+. Under similar conditions in the small intestine, ferrous ion can exist at 10-1M. As we will see, this difference in solubility plays a profound role in the absorption and availability of iron from our diets.26
Clinical consequences of controversies in gastric physiology
Published in Scandinavian Journal of Gastroenterology, 2020
This review describes how misinterpretations in gastric physiology have affected development in the treatment and understanding of diseases in the upper gastrointestinal tract. Moreover, these errors have often supported the view that long-term marked hypoacidity does not imply any risk, although production of acid in the upper gastrointestinal tract has been preserved during evolution. This review will not cover the biological consequences of removal of the biological function of the gastric juice; killing of swallowed microorganisms. Taking into consideration that we do not know the cause of most diseases that thus may be due to microorganisms, the lack of this biological function may by itself have serious consequences [1]. Instead, the focus will be on the relationship between physiology and clinical medicine including carcinogenesis.
Prebiotic Chondroitin Sulfate Disaccharide Isolated from Chicken Keel Bone Exhibiting Anticancer Potential Against Human Colon Cancer Cells
Published in Nutrition and Cancer, 2019
Aruna Rani, Rwivoo Baruah, Arun Goyal
CS-Keel disaccharide was studied for its hydrolysis in the presence of artificial gastric juice by the method adapted from previous study (28). The artificial gastric juice was composed of 1000 U mL−1 of pepsin in 1x Phosphate Buffer Saline (PBS) (29). The pH of artificial gastric juice was adjusted to 1, 2, 3, and 4 by 4 N HCl. CS-Keel disaccharide (0.5%, w/v) was dissolved in 20 mL of artificial gastric juice of each pH and incubated at 37 °C for 5 h. At intervals of 0, 0.5, 1, 2, 3, 4 and 5 h, an aliquot of 500 µL from the reaction mixture was withdrawn. The samples collected were quantified using HPLC system, connected with Phenomenex Rezex ROA-Organic Acid column (Phenomenex, CA) using RI and UV detectors set at 232 nm. The eluent used was 5 mM H2SO4 with a flow rate of 0.5 mL min−1. C4S disaccharide (Sigma–Aldrich, USA) from 0.05 to 0.5% (w/v) was used as a standard. The percent hydrolysis of the sample was estimated by the CS-Keel disaccharide content before and after the reaction using the equation as follows:
Fluorescent nanoparticles present in Coca-Cola and Pepsi-Cola: physiochemical properties, cytotoxicity, biodistribution and digestion studies
Published in Nanotoxicology, 2018
Shen Li, Chengkun Jiang, Haitao Wang, Shuang Cong, Mingqian Tan
Artificial digestive juices for in vitro digestion experiments were prepared according to the literature (Peters et al. 2012). The saliva (pH = 6.8) contained 896 mg KCl, 200 mg KSCN, 1021 mg NaH2PO4·H2O, 570 mg Na2SO4, 298 mg NaCl, 1694 mg NaHCO3, 200 mg urea, 290 mg amylase, 15 mg uric acid, 25 mg mucin and 1000 mL distilled water. The gastric juice (pH = 1.3) consisted of 2752 mg NaCl, 306 mg NaH2PO4·3H2O, 824 mg KCl, 302 mg CaCl2, 6.5 mL glucose, 20 mg glucuronic acid, 85 mg urea, 330 mg glucosamine hydrochloride, 1 g BSA, 2.5 g pepsin, 3 g mucin and 1000 mL distilled water. The duodenal juice (pH = 8.1) was composed of 7012 mg NaCl, 3388 mg NaHCO3, 80 mg KH2PO4, 564 mg KCl, 50 mg MgCl2·6H2O, 180 μL HCl (37%), 100 mg urea, 151 mg CaCl2, 1 g BSA, 9 g pancreatin, 1.5 g lipase and 100 mL distilled water. The bile juice (pH = 8.2) contained 5259 mg NaCl, 5785 mg NaHCO3, 376 mg KCl, 150 μL HCl (37%), 250 mg urea, 167.5 mg CaCl2, 1.8 g BSA, 30 g bile and 100 mL distilled water. The NaHCO3 solution was prepared by adding 84.0 g NaHCO3 in to 1000 mL distilled water. HEPES (4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid, 1 M) buffer was prepared by adding 119.15 g HEPES to 500 mL distilled water, and adjusting with 1 M NaOH solution to pH 7.0.