Diarrhea in the International Traveler.

PubMed

Duchini; Rodgers

1999-06-01

International travelers to developing countries have a 40% risk of developing a diarrheal illness, usually acute and occasionally chronic. Preventive measures, including diet and lifestyle modifications, are highly recommended but may not be sufficient. Prophylaxis with bismuth subsalicylate or an antimicrobial should be considered in travelers with immunodeficiencies, co-morbid conditions, achlorhydria, or those who cannot afford a loss of time. Oral rehydration is the primary goal of therapy. Bismuth-subsalicylate is a first-line agent for treatment of milder cases with less than three watery bowel movements per day and prominent nausea. Use of an antibiotic is indicated for more severe cases or in the presence of fever, dysentery, or severe dehydration. A short course of a quinolone is highly effective, safe and well tolerated. Antimicrobial resistance among enteropathogens is growing and appropriate therapeutic modifications should be considered according to specific geographic areas. Metronidazole may be empirically added in those cases that do not respond to quinolones. Specific guidelines for particular pathogens are highlighted.

Autoimmune gastritis: relationships with anemia and Helicobacter pylori status.

PubMed

Villanacci, Vincenzo; Casella, Giovanni; Lanzarotto, Francesco; Di Bella, Camillo; Sidoni, Angelo; Cadei, Moris; Salviato, Tiziana; Dore, Maria Pina; Bassotti, Gabrio

Autoimmune gastritis (AIG) is a gastric pathologic condition affecting the mucosa of the fundus and the body and eventually leading to hypo-achlorhydria. We report our clinical and pathological experience with AIG. Data from patients with a diagnosis of AIG seen in the period January 2002-December 2012 were retrieved. Only patients with complete sets of biopsies were analyzed. Data from 138 patients were available for analysis. Pernicious anemia was present in 25% of patients, iron deficiency anemia was found in 29.7% of patients, hypothyroidism in 23% of patients, type 1 diabetes in 7.9% of patients, and vitiligo in 2.8% of patients. Parietal cell antibodies were positive in 65% of patients, and no patient had serology positive for celiac disease. All gastric biopsies showed glandular atrophy associated with enterochromaffin-like (ECL)-cells hyperplasia, features limited to the mucosa of the fundus and body, and focal glandular intestinal metaplasia. Helicobacter pylori was negative in all cases. AIG was strongly associated with anemia; atrophy, intestinal metaplasia and ECL hyperplasia in the gastric fundus and body are hallmarks of this condition.

Dual isotope Schilling test for measuring absorption of food-bound and free vitamin B12 simultaneously

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doscherholmen, A.; Silvis, S.; McMahon, J.

1983-10-01

A prototype food-bound vitamin B12 (food-B12) absorption test has been developed in which /sup 57/Co-B12 was incorporated in vitro into egg yolk (yolk-B12) and served to volunteers in 50-g cooked portions together with toast and coffee for breakfast. Six hours later, 1 mg nonlabeled B12 was given intramuscularly and 24-hour urine was collected for radioactivity measurement. In separate tests, the absorption of yolk-B12 and crystalline /sup 57/Co-B12 was equally poor in patients with pernicious anemia. However, in patients with simple gastric achlorhydria and those who had undergone gastric surgery, the assimilation of yolk-B12 was impaired greatly, whereas the absorption ofmore » crystalline radio-B12 was normal. Egg yolk labeled with /sup 58/Co-B12 was administered together with crystalline /sup 57/Co-B12 in a dual isotope test with results similar to those obtained when the tests were prepared separately. This yolk-/sup 58/Co-B12 test with its ability to detect malabsorption of food-B12 may be considered as an addition to the first part of the Schilling test.« less

Review article: Pathogenesis and management of gastric carcinoid tumours.

PubMed

Burkitt, M D; Pritchard, D M

2006-11-01

Gastric carcinoid tumours are rare, but are increasing in incidence. To discuss tumour pathogenesis and outline current approaches to patient management. Review of published articles following a Pubmed search. Although interest in gastric carcinoids has increased since it was recognized that they are associated with achlorhydria, to date there is no definite evidence that humans taking long-term acid suppressing medication are at increased risk. Type I tumours are associated with autoimmune atrophic gastritis and hypergastrinaemia, type II are associated with Zollinger-Ellison syndrome, multiple endocrine neoplasia-1 and hypergastrinaemia and sporadic type III carcinoids are gastrin-independent and carry the worst prognosis. Careful investigation of these patients is required, particularly to identify the tumour type, the source of hypergastrinaemia and the presence of metastases. Treatment can be directed at the source of hypergastrinaemia if type I or II tumours are still gastrin responsive and not growing autonomously. Type III tumours should be treated surgically. Advances in our understanding of the pathogenesis of gastric carcinoids have led to recent improvements in investigation and management. Challenges remain in identifying the genetic and environmental factors, in addition to hypergastrinaemia, that are responsible for tumour development in susceptible patients.

Small intestinal function and dietary status in dermatitis herpetiformis.

PubMed Central

Gawkrodger, D J; McDonald, C; O'Mahony, S; Ferguson, A

1991-01-01

Small intestinal morphology and function were assessed in 82 patients with dermatitis herpetiformis, 51 of whom were taking a normal diet and 31 a gluten free diet. Methods used were histopathological evaluation of jejunal mucosal biopsy specimens, quantitation of intraepithelial lymphocytes, cellobiose/mannitol permeability test, tissue disaccharidase values, serum antigliadin antibodies, and formal assessment of dietary gluten content by a dietician. There was no correlation between dietary gluten intake and the degree of enteropathy in the 51 patients taking a normal diet, whereas biopsy specimens were normal in 24 of the 31 patients on a gluten free diet, all previously having been abnormal. Eighteen patients on gluten containing diets had normal jejunal histology and in seven of these all tests of small intestinal morphology and function were entirely normal. Intestinal permeability was abnormal and serum antigliadin antibodies were present in most patients with enteropathy. Studies of acid secretion in seven patients showed that hypochlorhydria or achlorhydria did not lead to abnormal permeability in the absence of enteropathy. This study shows that a combination of objective tests of small intestinal architecture and function will detect abnormalities in most dermatitis herpetiformis patients, including some with histologically normal jejunal biopsy specimens. Nevertheless there is a small group in whom all conventional intestinal investigations are entirely normal. PMID:2026337

[Iron deficiency and pernicious anemia: a rare association?].

PubMed

Zulfiqar, Abrar-Ahmad; Dramé, Moustapha; Pennaforte, Jean-Loup; Novella, Jean-Luc; Vogel, Thomas; Andres, Emmanuel

2015-01-01

The aim of this study was to determine the prevalence of iron deficiency among patients with pernicious anemia. We realized a retrospective study from 2000 to 2010 including 55 patients suffering from pernicious anemia who were followed in Reims and Strasbourg university hospitals. Inclusion criteria were histological diagnosis of immune atrophic fundic gastritis and criteria of gastric autoimmuninty, and for which ferritin was measured. Iron deficiency is defined as serum ferritin level <20 μg/L in women and <30 μg/L in men. 45 (81.8%) patients were female. The mean age was 61 ± 17 years (range: 25/98).There was anemia in 32 patients (58.2%). Macrocytosis was noted, with or without anemia, in 30 patients (54.5%); microcytosis, with or without anemia, was noted in 8 (14.5%) patients. 17 patients (30.9%) had normal mean corpuscular volume. Vitamin B12 deficiency was objectived in 42 patients (76.4%) in our series. 16 patients (29%) had iron deficiency. 14 patients were female. They were significantly younger than female subjects without iron deficiency (p =0.004). In conclusion, iron deficiency is not rare in patients with pernicious anemia. It could be a complication of achlorhydria. We suggest a dosage of serum ferritin for all patients with pernicious anemia.

Reliability of the dual-isotope Schilling test for the diagnosis of pernicious anemia or malabsorption syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Domstad, P.A.; Choy, Y.C.; Kim, E.E.

1981-05-01

To evaluate the dual-isotope Schilling test for the diagnosis of pernicious anemia or malabsorption syndrome, 65 studies were selected for clinical correlation. Criteria for pernicious anemia included mean corpuscular volume greater than 100 cu micrometer, serum B12 greater than 100 ng/l, megaloblastic marrow, achlorhydria, reticulocytes greater than 5% on B12 therapy, atrophic gastritis, and elevated serum antibodies to parietal cells or intrinsic factor. Criteria for malabsorption syndrome included: decreased serum B12, folate, and carotene; increased fecal fat; abnormal D-xylose absorption; abnormal radiographic and biopsy findings. /sup 58/Co-cyanocobalamin and /sup 57/Co-cyanocobalamin bound to intrinsic factor were given orally to fasting patients;more » 1 mg of nonradioactive B12 was injected intramuscularly within two hours. Aliquots of 24-hour urine samples were counted. If the excretion of /sup 58/Co was less than 7% and the /sup 57/Co//sup 58/Co ratio was greater than 1.7, the test indicated pernicious anemia; a ratio less than 1.7 indicated malabsorption syndrome. Sensitivity, specificity, and accuracy of the dual-isotope Schilling test were 83%, 98%, and 94% for pernicious anemia, and 67%, 90%, and 86% for malabsorption syndrome, respectively.« less

Serum Gastrin in Chronic Gastritis

PubMed Central

Korman, M. G.; Strickland, R. G.; Hansky, J.

1971-01-01

Fasting gastrin levels in serum were measured in 49 patients with different types of chronic gastritis and in matched controls. In 15 patients with established pernicious anaemia the mean (± S.E. of mean) level of gastrin was greatly raised (699 ± 99 pg/ml). In 17 patients with chronic atrophic gastritis, seropositive for parietal cell antibody but with adequate vitamin-B12 absorption, the level was also raised (476 ± 74 pg/ml). By contrast, in “simple” atrophic gastritis seronegative for parietal cell antibody the gastrin levels were significantly lower for both diffuse atrophic gastritis (129 ± 31 pg/ml) and multifocal gastritis (14 ± 4 pg/ml). These levels were similar to those in the controls (46 ± 7 pg/ml). The mechanism of the raised gastrin levels remains uncertain, but neither achlorhydria nor in vivo action of the parietal cell antibody wholly accounted for the hypergastrinaemia. We conclude that hypergastrinaemia is characteristic of gastritis associated with autoimmune reactions to gastric antigens and pernicious anaemia and that a raised serum gastrin is a useful marker of the type of gastritis that tends to progress to the gastric lesion of pernicious anaemia. The findings suggest that this type of gastritis is an essentially different disease from “simple” atrophic gastritis, and the differences in gastrin levels may be due to sparing of the antral mucosa in the autoimmune type but not in “simple” gastritis. PMID:5550864

[Gastric Cancer in Early Stage: study of 371 lesions in 340 patients in the E. Rebagliati National, Lima-Peru].

PubMed

Espejo Romero, Hernán; Navarrete Siancas, Jesús

2005-01-01

The first concrete description of the Gastric Cancer in Early Stage is attributed to the German, M. Versé in 1903, in his book Die Histogenese der Schleimhautcarcinome, but the first to use the term, was the French, Bayle in 1833, calling it First Stage Gastric Cancer. From 1963 to 2002, 5118 gastric cancers were histologically diagnosed, in our hospital from which 2337 (46%) were resected in 340 of the resected specimens, 371 early gastric cancers (EGC) (15.87%) were found. For every five periods, the number and proportion of early cancers increases, from 10 (6.8%) in the first five years to 78 (21.0%) in the last one. AGE: The average is: 64 years old for men and 58 for women with a global average of 61 years old. The youngest case was in a woman of 23 years old. The oldest case in men was 93 years old, and in women, 81 years old. SEX: 235 males and 105 females, with a ratio of 2,2:1. elevated type: Type l 70 (18.9%) Ila 66 (17.8%) Ila+Ilc 26 (7.0%) lla+l 1 (0.3%) I+lla 0 (0.0) IIa+III 1 (0.3%) IIa+IIb 1 (0.3%). Global average of the elevated type: 44.6%. llb 17 (4.6%), DEPRESSED TYPE: llb+llc 10 (2.7%), llc 127 (34.2%), llc+l 0 (0.0%) llc+lll 43 (11.6%) lll 3 (0.8%) lll+llc 5 (1.3%) llc+lla 1 (0.3%) lla+llb 0 (0.0%). The global average of the depressed type is: 50.9%. Antrum 171 (46.1%) body 138 (37.3%) bottom 46 (12.3%) antrum-body 12 (3%) and body-bottom 3 (1%). SIZE: Maximum 90 mm, minimum 1.5 mm, average 24.9 mm; 25 (8%) diminute (microcarcinomas), 58 (21%) small. Differentiated 219 (64%) undifferentiated 121 (36%). Degree of differentiation in men 74% and in women 26%. Degree of differentiation in diminutes 92%, in small 79% and in large 69%. DEPTH: 204(55%) in mucous, 167(45%) in mucous/submucous. In differentiated 182 (63%) in mucous, 108 (37%) in mucous/submucous. In the 187 located in mucous, 13 (3.8%) were positive, in the 153 located in mucous/submucous 30 (8.8%) were positive. Global percentage of positive ganglions: 12.3%. General in synchronic lesions in 54.6% in other types of cancer 12.7%. Present in 65%, of which 50% of them were uncompleted. Dyspepsia 82.2%, hyperoxia 32.9%, loss of weight 23.3%, non-characteristic pain 23.3%, ulcer pain 20.5%, melena 8.2%, anemia 7.7%, diarrhea and/or constipation 7.4%, vomiting 2.2%, hematemesis 1.9%. O (63.2%) A (24.7%) B (11.3%) AB (0.6%). This was determined in 70 patients: In 55 with ulcer, none showed achlorhydria 0%, 20 (36%) hypochlorhydria, 20 (36%) normochlorhydria and 15 (28%) hyperacidity. In 16 in an elevated form 13 (87.5%) with achlorhydria, 1 (6.5%) with hypochlorhydria, 1 (6.5%) with normal acidity. Average in ulcerated cases DAB 3.04 +/- 1.25 mEqh and DAM 12.31 +/- 8.00. In elevated cases: DAB 0.89 +/- 0.32 and DAM 2.20 +/- 0.95 mEqh.

[Plummer-Vinson syndrome or related syndrome in 3 black African women].

PubMed

Aubry, P; Oddes, B; Chazouillères, O; Lebourgeois, M; Delanoue, G; Seurat, P L

1985-01-01

The Plummer-Vinson syndrome or "sideropenic dysphagia" is exceptional among Blacks. One case was recently reported in a female patient from Guadeloupe. This study pertains to three cases observed in Senegalese Black women aged 28, 27, and 41 years. These three women were admitted for a dysphagia, in fact in evidence 10, 4, and 7 years respectively before the diagnosis was made. A clinical anemia was noted twice in addition to mucocutaneous disorders (cases 1 and 2). The laboratory tests showed in all three cases a hypochromic microcytic sideropenic anemia (serum iron levels at 32, 14, and 31 mcg 100 ml respectively). Barium swallow films showed esophageal rings in front of C5-C6 (case 1) of T2-T3 (case 2) and a web of fine mucosal folds in front of C5-C6 (case 3). These films were confirmed cineradiographically by esophagoscopy. The treatment consisted of blood transfusions (cases 1 and 2) and administration of iron by injections and or per os. The endoscopic exams were repeated two or three times. Medical treatment rapidly changed the course of disease for the better. No cause for bleeding was found. A chemical achlorhydria (case 1), a provoked hypoachlorhydria (cases 2 and 3) can be retained as associated factors. In light of the frequency of esophageal membranes in the general population and the incidence of sideropenic anemias among African women, the Plummer-Vinson syndrome should be more often detected in Black Africa.

Epstein-Barr virus-associated gastric carcinoma among patients with pernicious anemia.

PubMed

Boysen, Trine; Friborg, Jeppe; Stribolt, Katrine; Hamilton-Dutoit, Stephen; Goertz, Sanne; Wohlfahrt, Jan; Melbye, Mads

2011-12-01

Approximately 9% of gastric carcinomas worldwide are associated with Epstein-Barr virus (EBV), making it the most frequent EBV-associated malignancy. Pernicious anemia, a condition with chronic gastritis and achlorhydria, is strongly associated with gastric carcinoma. Both chronic inflammation and the lack of stomach acid may influence the likelihood of EBV infection of the neoplastic gastric epithelium, but the prevalence of EBV-associated gastric carcinoma among patients with pernicious anemia is unknown. Therefore, we conducted a Danish nationwide case-control study comparing gastric carcinoma patients with pernicious anemia (PA-GC) with those without pernicious anemia (nonPA-GC), frequency matched 1:2. Tumor tissues were reclassified by expert histopathologists blinded to pernicious anemia and EBV status. In total, 186 samples (55 PA-GC and 131 nonPA-GC) were identified. EBV-associated gastric carcinoma (EBV-GC) was more common among PA-GC compared with nonPA-GC, adjusted odds ratio (OR) = 2.53 (CI: 0.88; 7.14), p = 0.08, with further adjustment for lymphocytic infiltrate OR = 2.94 (0.99-8.67), p = 0.05. Gastric carcinomas with signet-ring cell morphology were significantly less common in patients with PA-GC compared with nonPA-GC (OR = 0.05, CI 0.01; 0.24). Although these conditions are rare, we found suggestive evidence that EBV-associated gastric carcinomas are more common among gastric carcinoma patients with pernicious anemia compared with those without. Copyright © 2011 UICC.

Small intestinal bacterial overgrowth syndrome

PubMed Central

Bures, Jan; Cyrany, Jiri; Kohoutova, Darina; Förstl, Miroslav; Rejchrt, Stanislav; Kvetina, Jaroslav; Vorisek, Viktor; Kopacova, Marcela

2010-01-01

Human intestinal microbiota create a complex polymicrobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequence for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO). SIBO is defined as an increase in the number and/or alteration in the type of bacteria in the upper gastrointestinal tract. There are several endogenous defence mechanisms for preventing bacterial overgrowth: gastric acid secretion, intestinal motility, intact ileo-caecal valve, immunoglobulins within intestinal secretion and bacteriostatic properties of pancreatic and biliary secretion. Aetiology of SIBO is usually complex, associated with disorders of protective antibacterial mechanisms (e.g. achlorhydria, pancreatic exocrine insufficiency, immunodeficiency syndromes), anatomical abnormalities (e.g. small intestinal obstruction, diverticula, fistulae, surgical blind loop, previous ileo-caecal resections) and/or motility disorders (e.g. scleroderma, autonomic neuropathy in diabetes mellitus, post-radiation enteropathy, small intestinal pseudo-obstruction). In some patients more than one factor may be involved. Symptoms related to SIBO are bloating, diarrhoea, malabsorption, weight loss and malnutrition. The gold standard for diagnosing SIBO is still microbial investigation of jejunal aspirates. Non-invasive hydrogen and methane breath tests are most commonly used for the diagnosis of SIBO using glucose or lactulose. Therapy for SIBO must be complex, addressing all causes, symptoms and complications, and fully individualised. It should include treatment of the underlying disease, nutritional support and cyclical gastro-intestinal selective antibiotics. Prognosis is usually serious, determined mostly by the underlying disease that led to SIBO. PMID:20572300

Review article: the investigation and management of gastric neuroendocrine tumours.

PubMed

Basuroy, R; Srirajaskanthan, R; Prachalias, A; Quaglia, A; Ramage, J K

2014-05-01

Gastric carcinoids (GCs) or neuroendocrine tumours (NETs) are increasingly identified at endoscopy, and account for 0.6-2% of all gastric polyps identified. The SEER database in the US has demonstrated a rising incidence of gastric NETs amongst all NETs; from 2.2% between 1950 and 1969 to 6.0% between 2000 and 2007. To review the literature and assist clinicians in managing patients with GCs. A literature search was conducted through MEDLINE using search terms: gastric, carcinoid, neuroendocrine tumour, therapy, endoscopy, mucosal resection, submucosal dissection. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles. There are three types of GCs with important epidemiological, pathophysiological, histological and endoscopic differences that affect prognosis and management. Type 1 and 2 GCs develop in the context of hypergastrinaemia that originates from achlorhydria in atrophic gastritis and a gastrinoma, respectively. Type 3 GCs occur sporadically and independent of gastrin. The histological type, grade and Ki67 index are used to determine prognosis and direct clinical management. Type 1 GCs >1 cm in size and type 2 GCs should be assessed for invasion beyond the submucosa with EUS prior to endoscopic resection with EMR or ESD. Type 3 GCs should be managed as per recommendations for gastric adenocarcinoma. The treatment of advanced disease is multimodal. Patients with gastric carcinoids should be discussed in a specialist neuroendocrine tumour multidisciplinary meeting to ensure all treatment options are explored in localised and advanced disease. Areas of controversy exist that need further research. © 2014 John Wiley & Sons Ltd.

Regular Article Macroautophagy is Defective in Mucolipin 1-Deficient Mouse Neurons

PubMed Central

Curcio-Morelli, Cyntia; Charles, Florie A.; Micsenyi, Matthew C.; Cao, Yi; Venugopal, Bhuvarahamurthy; Browning, Marsha F.; Dobrenis, Kostantin; Cotman, Susan L.; Walkley, Steven U.; Slaugenhaupt, Susan A.

2013-01-01

Mucolipidosis Type IV is a neurodegenerative lysosomal disease clinically characterized by psychomotor retardation, visual impairment, and achlorhydria. In this study we report the development of a neuronal cell model generated from cerebrum of Mcoln1-/- embryos. Prior functional characterization of MLIV cells has been limited to fibroblast cultures gleaned from patients. The current availability of the mucolipin-1 knockout mouse model Mcoln1-/- allows the study of mucolipin1-defective neurons, which is important since the disease is characterized by severe neurological impairment. Electron microscopy studies reveal significant membranous intracytoplasmic storage bodies, which correlate with the storage morphology observed in cerebral cortex of Mcoln1-/- P7 pups and E17 embryos. The Mcoln1-/- neuronal cultures show an increase in size of LysoTracker and Lamp1 positive-vesicles. Using this neuronal model system, we show that macroautophagy is defective in mucolipin-1 deficient neurons and that LC3-II levels are significantly elevated. Treatment with rapamycin plus protease inhibitors did not increase levels of LC3-II in Mcoln1-/- neuronal cultures, indicating that the lack of mucolipin-1 affects LC3-II clearance. P62/SQSTM1 and ubiquitin levels were also increased in Mcoln1-/- neuronal cultures, suggesting an accumulation of protein aggregates and a defect in macroautophagy which could help explain the neurodegeneration observed in MLIV. This study describes, for the first time, a defect in macroautophagy in mucolipin-1 deficient neurons, which corroborates recent findings in MLIV fibroblasts and provides new insight into the neuronal pathogenesis of this disease. PMID:20600908

Enterococcus faecalis infection causes inflammation, intracellular oxphos-independent ROS production, and DNA damage in human gastric cancer cells.

PubMed

Strickertsson, Jesper A B; Desler, Claus; Martin-Bertelsen, Tomas; Machado, Ana Manuel Dantas; Wadstrøm, Torkel; Winther, Ole; Rasmussen, Lene Juel; Friis-Hansen, Lennart

2013-01-01

Achlorhydria caused by e.g. atrophic gastritis allows for bacterial overgrowth, which induces chronic inflammation and damage to the mucosal cells of infected individuals driving gastric malignancies and cancer. Enterococcus faecalis (E. faecalis) can colonize achlohydric stomachs and we therefore wanted to study the impact of E. faecalis infection on inflammatory response, reactive oxygen species (ROS) formation, mitochondrial respiration, and mitochondrial genetic stability in gastric mucosal cells. To separate the changes induced by bacteria from those of the inflammatory cells we established an in vitro E. faecalis infection model system using the gastric carcinoma cell line MKN74. Total ROS and superoxide was measured by fluorescence microscopy. Cellular oxygen consumption was characterized non-invasively using XF24 microplate based respirometry. Gene expression was examined by microarray, and response pathways were identified by Gene Set Analysis (GSA). Selected gene transcripts were verified by quantitative real-time polymerase chain reaction (qRT-PCR). Mitochondrial mutations were determined by sequencing. Infection of MKN74 cells with E. faecalis induced intracellular ROS production through a pathway independent of oxidative phosphorylation (oxphos). Furthermore, E. faecalis infection induced mitochondrial DNA instability. Following infection, genes coding for inflammatory response proteins were transcriptionally up-regulated while DNA damage repair and cell cycle control genes were down-regulated. Cell growth slowed down when infected with viable E. faecalis and responded in a dose dependent manner to E. faecalis lysate. Infection by E. faecalis induced an oxphos-independent intracellular ROS response and damaged the mitochondrial genome in gastric cell culture. Finally the bacteria induced an NF-κB inflammatory response as well as impaired DNA damage response and cell cycle control gene expression. Array Express accession number E-MEXP-3496.

Effect of famotidine on the pharmacokinetics of apixaban, an oral direct factor Xa inhibitor

PubMed Central

Upreti, Vijay V; Song, Yan; Wang, Jessie; Byon, Wonkyung; Boyd, Rebecca A; Pursley, Janice M; LaCreta, Frank; Frost, Charles E

2013-01-01

Background Apixaban is an oral, selective, direct factor Xa inhibitor approved for thromboprophylaxis after orthopedic surgery and stroke prevention in patients with atrial fibrillation, and under development for treatment of venous thromboembolism. This study investigated the effect of a gastric acid suppressant, famotidine (a histamine H2-receptor antagonist), on the pharmacokinetics of apixaban in healthy subjects. Methods This two-period, two-treatment crossover study randomized 18 healthy subjects to receive a single oral dose of apixaban 10 mg with and without a single oral dose of famotidine 40 mg administered 3 hours before dosing with apixaban. Plasma apixaban concentrations were measured up to 60 hours post-dose and pharmacokinetic parameters were calculated. Results Famotidine did not affect maximum apixaban plasma concentration (Cmax) or area under the plasma concentration-time curve from zero to infinite time (AUC∞). Point estimates for ratios of geometric means with and without famotidine were close to unity for Cmax (0.978) and AUC∞ (1.007), and 90% confidence intervals were entirely contained within the 80%–125% no-effect interval. Administration of apixaban alone and with famotidine was well tolerated. Conclusion Famotidine does not affect the pharmacokinetics of apixaban, consistent with the physicochemical properties of apixaban (lack of an ionizable group and pH-independent solubility). Apixaban pharmacokinetics would not be affected by an increase in gastrointestinal pH due to underlying conditions (eg, achlorhydria), or by gastrointestinal pH-mediated effects of other histamine H2-receptor antagonists, antacids, or proton pump inhibitors. Given that famotidine is also an inhibitor of the human organic cation transporter (hOCT), these results indicate that apixaban pharmacokinetics are not influenced by hOCT uptake transporter inhibitors. Overall, these results support that apixaban can be administered without regard to coadministration of gastric acid modifiers. PMID:23637566

Assessing the risk of pH-dependent absorption for new molecular entities: a novel in vitro dissolution test, physicochemical analysis, and risk assessment strategy.

PubMed

Mathias, Neil R; Xu, Yan; Patel, Dhaval; Grass, Michael; Caldwell, Brett; Jager, Casey; Mullin, Jim; Hansen, Luke; Crison, John; Saari, Amy; Gesenberg, Christoph; Morrison, John; Vig, Balvinder; Raghavan, Krishnaswamy

2013-11-04

Weak base therapeutic agents can show reduced absorption or large pharmacokinetic variability when coadministered with pH-modifying agents, or in achlorhydria disease states, due to reduced dissolution rate and/or solubility at high gastric pH. This is often referred to as pH-effect. The goal of this study was to understand why some drugs exhibit a stronger pH-effect than others. To study this, an API-sparing, two-stage, in vitro microdissolution test was developed to generate drug dissolution, supersaturation, and precipitation kinetic data under conditions that mimic the dynamic pH changes in the gastrointestinal tract. In vitro dissolution was assessed for a chemically diverse set of compounds under high pH and low pH, analogous to elevated and normal gastric pH conditions observed in pH-modifier cotreated and untreated subjects, respectively. Represented as a ratio between the conditions, the in vitro pH-effect correlated linearly with clinical pH-effect based on the Cmax ratio and in a non-linear relationship based on AUC ratio. Additionally, several in silico approaches that use the in vitro dissolution data were found to be reasonably predictive of the clinical pH-effect. To explore the hypothesis that physicochemical properties are predictors of clinical pH-effect, statistical correlation analyses were conducted using linear sequential feature selection and partial least-squares regression. Physicochemical parameters did not show statistically significant linear correlations to clinical pH-effect for this data set, which highlights the complexity and poorly understood nature of the interplay between parameters. Finally, a strategy is proposed for implementation early in clinical development, to systematically assess the risk of clinical pH-effect for new molecular entities that integrates physicochemical analysis and in vitro, in vivo and in silico methods.

Lack of commensal flora in H. pylori-infected INS-GAS mice reduces gastritis and delays intraepithelial neoplasia

PubMed Central

Lofgren, Jennifer L.; Whary, Mark T.; Ge, Zhongming; Muthupalani, Sureshkumar; Taylor, Nancy S.; Mobley, Melissa; Potter, Amanda; Varro, Andrea; Eibach, Daniel; Suerbaum, Sebastian; Wang, Timothy C.; Fox, James G.

2010-01-01

Background & Aims Transgenic, insulin–gastrin (INS–GAS) mice have high circulating levels of gastrin. On a FVB/N background, these mice develop spontaneous atrophic gastritis and gastrointestinal intraepithelial neoplasia (GIN) with 80% prevalence 6 months after Helicobacter pylori infection. GIN is associated with gastric atrophy and achlorhydria, predisposing mice to non-helicobacter microbiota overgrowth. We determined if germ-free INS–GAS mice spontaneously develop GIN and if H. pylori accelerates GIN in gnotobiotic INS–GAS mice. Methods We compared gastric lesions and levels of mRNA, serum inflammatory mediators, antibodies, and gastrin among germ-free and H. pylori-monoinfected INS-GAS mice. Microbiota composition of specific pathogen-free (SPF) INS-GAS mice was quantified by pyro-sequencing. Results Germ-free INS-GAS mice had mild hypergastrinemia but did not develop significant gastric lesions until they were 9 months old; they did not develop GIN through 13 months. H. pylori monoassociation caused progressive gastritis, epithelial defects, oxyntic gland atrophy, marked foveolar hyperplasia and dysplasia, and strong serum and tissue proinflammatory immune responses (particularly in male mice) between 5 and 11 months post infection (P<0.05, compared with germ-free controls). Only 2 of 26 female, whereas 8 of 18 male, H. pylori-infected INS-GAS mice developed low- to high-grade GIN by 11 months post infection. Stomachs of H. pylori-infected SPF male mice had significant reductions in Bacteroidetes and significant increases in Firmicutes. Conclusions Gastric lesions take 13 months longer to develop in germ-free INS–GAS mice than male SPF INS-GAS mice. H. pylori-monoassociation accelerated gastritis and GIN but caused less-severe gastric lesions and delayed onset of GIN compared to H. pylori-infected INS-GAS mice with complex gastric microbiota. Changes of gastric microbiota composition might promote GIN in the achlorhydric stomachs of SPF mice. PMID:20950613

Impact on human health of Salmonella spp. on pork in The Netherlands and the anticipated effects of some currently proposed control strategies.

PubMed

Berends, B R; Van Knapen, F; Mossel, D A; Burt, S A; Snijders, J M

1998-11-10

The impact on human health of Salmonella spp. on pork in The Netherlands is described. Subsequently, the effects of some currently proposed control strategies in the Dutch pork production chain are evaluated and quantified with the aid of a simple mathematical model. The estimated average incidence of cases of salmonellosis in the Netherlands is about 450 cases per 100,000 person years at risk (pyar). Some special risk groups for which the risks could be quantified are (1) persons with underlying diseases, such as neoplasms or diabetes mellitus (1200 cases/100,000 pyar); (2) persons with achlorhydria or who excessively use antacids (1100 cases/100,000 pyar); (3) persons who have recently been treated with antibiotics that disturb the normal gut flora (1700 cases/100,000 pyar); (4) nurses (900 cases/100,000 pyar); (5) caterers (900 cases/100,000 pyar); (6) slaughterline personnel (1800 cases/100,000 pyar). Furthermore, it is estimated that 15% (5-25%) of all cases of salmonellosis in The Netherlands are associated with the consumption of pork. Currently, proposed control measures regarding Salmonella in pigs and on pork in The Netherlands are codes of good manufacturing practices (GMP) that, in fact, formalize recommendations that can be found in many handbooks about pig breeding and pig slaughtering. When evaluated by a mathematical model constructed for this purpose, the proposed GMP codes from farm to cutting/retail could, at best, reduce the current levels of Salmonella-positive pigs and pork by 50-60%. If pigs were bred according to the rather costly specific pathogen-free concept (SPF), the prevalence of contaminated carcasses and pork could in total be reduced by 95% or more. However, implementing GMP codes from the transport phase up to the cutting/retail phase coupled with a decontamination step at the end of the slaughterline would be just as effective as GMP in combination with breeding using the SPF-concept. It is therefore concluded that the most efficient and cost-effective way of reducing the 'Salmonella problem' entailed by the consumption of pork would be to decontaminate carcasses under the precondition that the entire production chain strictly adheres to GMP principles. Therefore, the EU should also allow for more possibilities regarding the decontamination of carcasses than is currently the case. It is also concluded that current EU regulations relying on hazard analysis of critical control points (HACCP)-inspired production in cutting plants will not be effective in reducing the prevalence of Salmonella spp. on pork. This is mainly because (1) there is currently an almost steady stream of Salmonella-positive carcasses that enter the cutting process; (2) when contaminated carcasses are being processed, further cross-contamination during working hours is unavoidable; (3) no steps in the cutting process are intentionally designed to effectively reduce the risks or consequences of cross contamination of cuts and retail-ready products.