China
Africa
Explore chapters and articles related to this topic
Fundoplication
Published in Mark Davenport, James D. Geiger, Nigel J. Hall, Steven S. Rothenberg, Operative Pediatric Surgery, 2020
Douglas C. Barnhart, Robert A. Cina
The squamous epithelium of the esophagus is unable to resist the irritant effect of gastric juices. The acid pepsin causes a chemical inflammation with erythema of the mucosa. With continued reflux, the mucosa becomes friable and bleeds easily on contact. Later, frank ulceration develops, which, with repeated attempts at repair and relapse, eventually leads to stricture formation. This process is summarized in Figure 28.3.
The Small IntestineSecretions, Digestion and Motility
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
The actions of secretin are (i) the stimulation of pancreatic and water secretion, (ii) inhibition of gastric acid secretion and trophic effects of gastrin (nature's antacid), (iii) stimulation of pepsin secretion in the stomach and (iv) trophic effects on exocrine pancreas.
Macromolecular Absorption From The Digestive Tract In Young Vertebrates
Published in Károly Baintner, Intestinal Absorption of Macromolecules and Immune Transmission from Mother to Young, 2019
Besides splitting the Met-Phe bond, chymosin has a ‘‘general proteolytic activity.” This is much slower than that of pepsin, but its pH optimum is higher, approximately pH 3.0 to 3.5.1448 Chymosin is widely used in cheese production, and may have been the first enzyme used in the industry.
Recent advances in proteolytic stability for peptide, protein, and antibody drug discovery
Published in Expert Opinion on Drug Discovery, 2021
Xianyin Lai, Jason Tang, Mohamed E.H. ElSayed
The stomach secretes a mixture of compounds, including water, mucus, hydrochloric acid, pepsin, and intrinsic factors. Among them, pepsin is the principal enzyme involved in peptide, protein, and antibody digestion, generating smaller peptides and amino acids [52]. Pepsin is an endopeptidase that breaks down peptide bonds within a polypeptide sequence through aspartic catalysis mechanism at a low pH (1.5–2.0) [53]. The proteolytic stabilities of the bovine serum albumin, ovomucoid, β-lactoglobulin A, β-lactoglobulin B, and lysozyme were evaluated with 3.2 mg/mL pepsin in simulated gastric fluids prepared as described in the United States Pharmacopoeia. Bovine serum albumin and ovomucoid were observed to be rapidly digested within 0.25 min at the beginning of the incubation time. Lysozyme was completely degraded in 30 min. β-lactoglobulin A and β-lactoglobulin B had degradation percentages of 34.3% and 17.2% after 60 min of incubation [51].
Narrow-band imaging combined with salivary pepsin to diagnose patients with laryngopharyngeal reflux
Published in Acta Oto-Laryngologica, 2021
Pepsin is a proteolytic enzyme whose precursor pepsinogen is produced only in the stomach. Therefore, an increased pepsin level in the saliva is considered a specific biomarker for gastric reflux or LPR. Detecting salivary pepsin using the fibrinogen digestion method, western blot analysis, and enzyme-linked immunosorbent assay (ELISA) is considered to be convenient and non-invasive [4]. Given the non-invasive nature of this test, it was considered to be a useful method in the diagnosis of gastroesophageal reflux disease [19]. In a study with 58 patients with GERD (diagnosed by esophagitis and/or abnormal pH) compared to 51 controls, a salivary pepsin test was performed with an 81% positive predictive value and a 78% negative predictive value [20]. In our study, we initially defined the threshold of pepsin as 33 ng/mL through ROC analysis. Further analysis showed that salivary pepsin levels were significantly correlated with RFS/RSI scores which means that salivary pepsin measurements have compared well against RFS/RSI score system.
Educational intervention can improve appropriateness of acid suppression therapy in hospitalized geriatric patients
Published in Journal of Community Hospital Internal Medicine Perspectives, 2019
Sankalp Dwivedi, Jaya Edukulla, Sindhu Rajendra, Sandesh Murali, Serge A. Sorser, Marc S. Piper, Michael Piper, Bradley J. Warren, Harsha Ramchandani
Gastric acid plays an essential role in the digestion of protein by converting pepsinogen to the active form, pepsin. It also prevents against enteric infection, bacterial overgrowth and facilitates the absorption of vitamin B12, non-heme iron, and medications such as calcium and thyroxin [1]. Consequences of hypochlorhydria have been well defined in the literature: (1) Osteoporosis and Hip Fracture [2]; (2) Hospital acquired pneumonia and community acquired pneumonia [3,4]; (3) Clostridium difficile infection [5]; (4) Vitamin B 12 deficiency [6]; (5) Alteration in the lower intestinal microflora [7]; (6) Various forms of kidney injury have also been linked to the Proton Pump Inhibitors (PPIs) use such as acute allergic interstitial nephritis, acute kidney injury, increased incidence of chronic kidney disease and progression to end stage renal disease [8].