Influence of gastric pH on gastric and jejunal flora.

Role of Gastric Colonization in Nosocomial Infections and Endotoxemia: A Prospective Study in Neurosurgical Patients on Mechanical Ventilation

“…The results of this study confirm that intragastric microbial growth is pH-dependent [18][19][20] and promoted by treatment with Hs-receptor blockers or antacids [3][4][5][6][7][8]. However, our data do not support results from previous studies on intubated ICU patients, which suggested that gastric colonization was a significant risk factor for subsequent tracheal colonization or pneumonia [5,[8][9][10].…”

The Interdigestive Motor Complex of Normal Subjects and Patients with Bacterial Overgrowth of the Small Intestine

“…Patient K. L. had undergone a total gastrectomy 3 yr previously. Anacidity may have contributed to the development of bacterial overgrowth in this patient (20,21). A. R. had Crohn's disease of the ileum.…”

Gastrectomy Increases the Expression of Hepatic Cytochrome P450 3A by Increasing Lithocholic Acid-Producing Enteric Bacteria in Mice

“…The pH in the gastrointestinal tract of patients with gastrectomy increases due to a decrease in or lack of gastric acid secretion. 12) In the intestinal environment, where the pH is high, the level of enteric bacteria with an elevated activity of the enzyme 7α-dehydroxylase, which converts chenodeoxycholic acid to LCA, 13) increases. LCA activates hepatic nuclear receptors, such as PXR or CAR, which cause an increase in the expression level of hepatic CYP3A.…”

“…12) In particular, the levels of LCA-producing bacteria, which are known to thrive under alkaline conditions, increased. 13) We therefore hypothesized and attempted to verify that the following reasons may increase the hepatic expression level of CYP3A upon gastrectomy. In patients with gastrectomy, the level of LCA in the large intestine increased due to the increase in the pH of the gastrointestinal tract, which in turn causes the increase in the level of LCA-producing bacteria.…”