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Gastrointestinal system
Published in Jagdish M. Gupta, John Beveridge, MCQs in Paediatrics, 2020
Jagdish M. Gupta, John Beveridge
6.7. Which of the following statements is/are correct?Enteropeptidase (enterokinase) deficiency causes malabsorption.Amylase deficiency usually causes diarrhoea.Cholestatic disorders of the liver give rise to fat globules in the stools.Massive diarrhoea can occur with neuroblastoma.The peripheral neuritis associated with abetalipoproteinaemia is due to vitamin A deficiency.
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
Enterokinase already is active in the proximal small intestine of young mammals, as indicated by the activation of trypsinogen. Enterokinase activity is not suppressed by the colostral inhibitor,51 which affects only the product of the reaction, namely, the activated trypsin. The remainder of the pancreatic zymogens (chymotrypsinogens, proelastase, procarboxypeptidases, and prophospholipases) are activated by trypsin, and in vitro addition of excess trypsin inhibitor suppresses these secondary reactions. The requirement of trypsin for the activation of zymogens may explain the wider occurrence of trypsin inhibitors than any other protease inhibitor in nature; however, chemical causes may also underlie the phenomenon. We have no experimental proof for the in vivo inhibition of activation of zymogens by any of the trypsin inhibitors.
The digestive system
Published in Laurie K. McCorry, Martin M. Zdanowicz, Cynthia Y. Gonnella, Essentials of Human Physiology and Pathophysiology for Pharmacy and Allied Health, 2019
Laurie K. McCorry, Martin M. Zdanowicz, Cynthia Y. Gonnella
Protein digestion begins in the stomach by the action of the gastric enzyme, pepsin. This enzyme fragments large protein molecules into smaller peptide chains. Digestion is continued in the small intestine by the pancreatic enzymes, trypsin, chymotrypsin, and carboxypeptidase. Similar to pepsin (pepsinogen), these enzymes are secreted as inactive precursors (trypsinogen, chymotrypsinogen and procarboxypeptidase). The intestinal enzyme enterokinase activates trypsin at the brush border. Trypsin then activates chymotrypsin and carboxypeptidase. These pancreatic enzymes hydrolyze the peptide chains into amino acids (40%), as well as dipeptides and tripeptides (60% combined).
Medicinal plants in mitigating electromagnetic radiation-induced neuronal damage: a concise review
Published in Electromagnetic Biology and Medicine, 2022
Shamprasad Varija Raghu, Avinash Kundadka Kudva, Golgodu Krishnamurthy Rajanikant, Manjeshwar Shrinath Baliga
Curcuma amada, also known as mango ginger (Figure 1), has a morphological resemblance to ginger (Zingiber officinale) and imparts a raw mango flavor (Mangifera indica).It is related to turmeric and belongs to the Zingiberaceae family. Mango ginger rhizomes are a popular spice and vegetable due to their rich flavor.It is used in South Asian, Southeast Asian, and Far East Asian cuisines. It is primarily used in chutneys and pickles in India (Jatoi et al. 2007). Phenolic acids, volatile oils, starch, curcuminoids, terpenoids, flavonoids, alkaloids, glycosides, tannins, phytosterols, and saponins are among the major phytochemicals found in Curcuma amada. The ethanolic extract of mango zinger rhizome revealed the presence of hydroxyl, carbonyl, ester, and olefin functional groups. It also contains methyl, methylene, methionine proteins and olefinic proteins (Mujumdar et al. 2004). It has different pharmacological activities and medicinal values such as antibacterial, cytotoxic, antiallergic, hypo-triglyceridemic and enterokinase inhibitory activities. It also has central nervous system (CNS) depressant, analgesic, and aphrodisiac activities (Policegoudra et al. 2011).
Trypsinogen and chymotrypsinogen: potent anti-tumor agents
Published in Expert Opinion on Biological Therapy, 2021
Aitor González-Titos, Pablo Hernández-Camarero, Shivan Barungi, Juan Antonio Marchal, Julian Kenyon, Macarena Perán
Trypsinogen is activated to the proteolytic enzyme Trypsin in the duodenum by enterokinase (Figure 2) which recognizes the specific sequence in the propeptide of Trypsinogen, Asp-Asp-Asp-Asp-Lys, and cleaves after the Lysine residue in the peptide bond Lys-23 and Ile-24 [15]. Other proteinases, such as matrix metalloproteinase-9 and cathepsin B, activate Trypsinogen but are related to acute pancreatitis [16,17]. Once the activation peptide is removed, a conformational change is observed in the protein structure which allows the substrate attachment in the specific pocket [18]. After Trypsin activation, in the 70–80 loop, three amino acids Glu-70, Glu-72 and Glu-80 bind Ca2+ increasing the stability of the active protein [19], so it is well within reason to assume that the Ca2+ concentration may condition Trypsin half-life and hence its biological activity.
The Prognostic Value of External vs Internal Pancreatic Duct Stents in CR-POPF after Pancreaticoduodenectomy: A Systematic Review and Meta-analysis
Published in Journal of Investigative Surgery, 2021
Yuancong Jiang, Qin Chen, Zhize Wang, Yi Shao, Chen Hu, Yuan Ding, Zhenhua Shen, Ming Jin, Sheng Yan
Catheter drainage has now been considered the first step of intervention for pancreatic fistula [46]. Many studies have indicated that an external stent can fully drain pancreatic juice which prevent the accumulation of pancreatic juice in the jejunal cavity and to maintain the patency of the main pancreatic duct. Pancreatic enzymes have also been drained out without being initiated by enterokinase in the jejunal cavity after surgery [47, 48]. However, external stents may cause the loss of large amounts of liquid and digestive enzymes, which results in delayed gastrointestinal function. Moreover, compared with internal stents, external stents result in a greater chance of stent-related complications, such as drainage tube discomfort, displacement, shedding or clogging, which may result in peritonitis, chronic pancreatitis or stenosis after removal of the stent [49]. In general, the effect of external stents on the prevention of CR-POPF is controversial.