bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human intestinal M cells exhibit enterocyte-like intermediate filaments
Authors: Kucharzik T , Lügering N , Schmid K W , Schmidt M A , Stoll R , Domschke W 
Published: June 2010

Background—The derivation and ultrastructural composition of M cells covering the lymphoid follicles of Peyer’s patches is still unknown. Results from different animal models have shown that there are species specific differences in the composition of intermediate filaments between M cells and neighbouring enterocytes. Little is known, however, about intermediate filaments of human M cells.Aims—To compare components of the cytoskeleton of human M cells with those of adjacent absorptive enterocytes.Methods—The expression and localisation of different cytokeratins, vimentin, and desmin in M cells was determined on follicle associated epithelia of human appendix using immunohistochemistry and immunogold electron microscopy.Results—Cytokeratins specific for human intestinal epithelial cells such as cytokeratins 8, 18, 19, and 20 were expressed in both absorptive enterocytes and M cells with no differences in intensity and cellular distribution between both cell types. Vimentin and desmin, tissue specific markers of either mesenchymal or myogenic cells, as well as other cytokeratins were not detectable in enterocytes or M cells.Conclusion—This is the first study on the structure of intermediate filaments in human intestinal M cells. Our results show that in contrast to several animal models, human M cells apparently do not differ from adjacent enterocytes in the composition of their intermediate filament cytoskeleton. The presence of enterocyte like cytokeratins and the absence of other cytokeratins as well as of vimentin and desmin supports the hypothesis of an epithelial origin of human intestinal M cells and suggests that M cells may derive from differentiated enterocytes.
Predictive factors for survival of patients with inoperable malignant distal biliary strictures: a practical management guideline
Authors: Prat F , Chapat O , Ducot B , Ponchon T , Fritsch J , Choury A D , Pelletier G , Buffet C 
Published: June 2010

Background—Stenting is the treatment of choice for inoperable malignant strictures of the common bile duct. Criteria for the choice of stents (plastic versus metallic) remain controversial because predicting survival is difficult.Aims—To define prognostic factors in order to improve the cost effectiveness of endoscopic palliation.Patients—One hundred and one patients were included in a prospective trial. Seven prognostic variables for survival were analysed (age, sex, bilirubinaemia, weight loss, presence of liver metastases, and tumour histology and size). All patients were followed until death or at least one year after inclusion. By the end of the study, 81 (80.2%) patients had died.Results—In univariate analysis, the variables associated with survival were weight loss (p<0.05) and tumour size (p<0.01). By multivariate analysis, tumour size was the only independent prognostic factor (p<0.05). A threshold of 30 mm at diagnosis distinguished two survival profiles: the median survival of patients with a tumour greater than 30 mm was 3.2 months, whereas it was 6.6 months for patients with a tumour less than 30 mm (p<0.001).Conclusions—A practical strategy could be based on tumour size at diagnosis: a metal stent should be systematically chosen for patients with an inoperable tumour smaller than 30 mm, while larger tumours are efficiently palliated by a plastic stent.
Anticipation in familial Crohn’s disease
Authors: Grandbastien B , Peeters M , Franchimont D , Gower-Rousseau C , Speckel D , Rutgeerts P , Belaïche J , Cortot A , Vlietinck R , Colombel J-F 
Published: June 2010

Background—Offspring with a family history of Crohn’s disease have an earlier age of onset than their parents. This might be due to genetic anticipation, characterised by earlier and/or more severe disease in subsequent generations.Aims—To investigate the possibility of genetic anticipation in affected parent-child pairs with Crohn’s disease from France and Belgium.Patients and methods—In a cohort of 160 multiply affected families with Crohn’s disease, 57 parent-first affected child pairs were detected. Clinical characteristics (age at diagnosis, disease extent, and type) of both parents and children were registered and compared.Results—Children were younger than their parents at diagnosis in 48/57 (84%) pairs. The median age at diagnosis was 16 years younger in children than in parents (p<0.0001). However, the difference was related to the age at diagnosis in the parents and was not present in 12 parent-child pairs with an early age at diagnosis for the parents. In most cases, disease extent and type were not considered more severe in children than in parents. Parental sex affected neither age at diagnosis nor extent and type of disease in children.Conclusion—Patients in the second affected generation acquire their disease at an earlier time in life in some but not all familial cases of Crohn’s disease. Several explanations including genetic anticipation and environmental factors might explain this phenomenon.
Omeprazole induces altered bile acid metabolism
Authors: Shindo K , Machida M , Fukumura M , Koide K , Yamazaki R 
Published: June 2010

Background—It has been reported that the acidity of gastric contents could be an important factor in regulating jejunal flora.Aims—To investigate the effects of omeprazole induced changes in gastric pH on jejunal flora and bile acid metabolism.Methods—Twenty one patients with gastric ulcer and 19 healthy volunteers were studied. Deconjugation of bile acids was detected using a bile acid breath test. Jejunal fluid was aspirated using a double lumen tube with a rubber cover on the tip and deconjugation was examined using thin layer chromatography. Fat malabsorption was detected by a triolein breath test.Results—In the bile acid breath test, expired breath samples from all patients and healthy volunteers showed significantly greater 14CO2 specific activity after omeprazole treatment (20 mg/day) than before treatment. Bacterial overgrowth was found in the jejunal fluid and gastric juice of both ulcer patients and healthy volunteers after omeprazole treatment. The following species were identified: Escherichia coli,Candida albicans, enterococcus, Lactobacillus bifidus, Bacteroides vulgatus, B uniformis, Eubacterium lentum, Eu parvum, and Corynebacterium granulosum. All of these species, except E coli and C albicans, deconjugate bile acids. There was a significant correlation between14CO2 activity and gastric pH, both before and after omeprazole treatment in both groups. The triolein breath test revealed impaired fat absorption in both groups after omeprazole treatment.Conclusions—Both patients with gastric ulcer and healthy volunteers exhibited increased deconjugation of bile acids caused by bacterial overgrowth in the jejunum and fat malabsorption after omeprazole treatment. The bacterial overgrowth consisted of both anaerobes and aerobes with deconjugation ability and was probably associated with an omeprazole induced shift to neutral pH in the gastric juice.
Major virulence factors, VacA and CagA, are commonly positive inHelicobacter pylori isolates in Japan
Authors: Maeda S , Ogura K , Yoshida H , Kanai F , Ikenoue T , Kato N , Shiratori Y , Omata M 
Published: June 2010

Background—VacA and CagA proteins have been reported to be major virulence factors of Helicobacter pylori. However, antibodies against these proteins are frequently found in the sera of Japanese patients regardless of their gastroduodenal status.Aim—To evaluate the expression of VacA and CagA proteins by H pylori strains isolated in Japan.Methods—By using specific antibodies raised against recombinant VacA and CagA proteins, the expression of VacA and CagA was evaluated in 68 H pylori strains isolated from Japanese patients; a vacuolating assay and genotyping of thevacA gene were also used in the evaluation. The results were analysed in relation to the gastroduodenal diseases of the hosts.Results—VacA and CagA proteins were expressed in 59/68 (87%) and in 61/68 (90%) isolates respectively. The vacuolating assay was positive in 57/68 (84%) isolates, indicating that most immunologically VacA positive strains produced active cytotoxin. The prevalence of infection with strains expressing CagA and positive for vacuolating activity (Type I) was very high, 54/68 (79%), irrespective of the gastroduodenal status of the host.Conclusion—Most H pylori isolates in Japan are positive for vacuolating cytotoxin and CagA, and thus these virulence factors cannot be used as markers to discern the risk of developing serious gastroduodenal pathologies in the hosts. However, the high prevalence of infection with strains positive for vacuolating cytotoxin and CagA may contribute to the characteristics of H pylori infection in Japan.
Oxidative DNA damage accumulation in gastric carcinogenesis
Authors: Farinati F , Cardin R , Degan P , Rugge M , Di Mario F , Bonvicini P , Naccarato R 
Published: June 2010

Background—Gastric carcinogenesis is a multifactorial, multistep process, in which chronic inflammation plays a major role.Aims—In order to ascertain whether free radical mediated oxidative DNA damage is involved in such a process, concentrations of 8-hydroxydeoxyguanosine (8OHdG), a mutagenic/carcinogenic adduct, and thiobarbituric acid reactive substances (TBARS), as an indirect measure of free radical mediated damage, were determined in biopsy specimens from patients undergoing endoscopy.Patients—Eighty eight patients were divided into histological subgroups as follows: 27 with chronic non-atrophic gastritis, 41 with atrophic gastritis, six with gastric cancer, and 14 unaffected controls.Methods—Intestinal metaplasia,Helicobacter pylori infection, and disease activity were semiquantitatively scored. 8OHdG concentrations were assessed by HPLC with electrochemical detection, and TBARS concentrations were fluorimetrically assayed.Results—8OHdG concentrations (mean number of adducts/105 dG residues) were significantly higher in chronic atrophic gastritis (p=0.0009). Significantly higher concentrations were also detected in the presence of severe disease activity (p=0.02), intestinal metaplasia (p=0.035), and H pylori infection (p=0.001). TBARS concentrations were also higher in atrophic gastritis, though not significantly so. In a multiple logistic regression analysis, 8OHdG concentrations correlated best with the presence and severity of H pylori infection (r=0.53, p=0.002).Conclusions—Chronic gastritis is characterised by the accumulation of oxidative DNA damage with mutagenic and carcinogenic potential. H pylori infection is the major determinant for DNA adduct formation.
Expression of arylamine N-acetyltransferase in human intestine
Authors: Hickman D , Pope J , Patil S D , Fakis G , Smelt V , Stanley L A , Payton M , Unadkat J D , Sim E 
Published: June 2010

Background—ArylamineN-acetyltransferases in humans (NAT1 and NAT2) catalyse the acetylation of arylamines including food derived heterocyclic arylamine carcinogens. Other substrates include the sulphonamide 5-aminosalicylic acid (5-ASA), which is an NAT1 specific substrate; N-acetylation of 5-ASA is a major route of metabolism. NAT1 and NAT2 are both polymorphic.Aims—To investigate NAT expression in apparently healthy human intestines in order to understand the possible role of NAT in colorectal cancer and in the therapeutic response to 5-ASA.Methods—The intestines of four organ donors were divided into eight sections. DNA was prepared for genotypingNAT1 and NAT2 and enzymic activities of NAT1 and NAT2 were determined in cytosols prepared from each section. Tissue was fixed for immunohistochemistry with specific NAT antibodies. Western blotting was carried out on all samples of cytosol and on homogenates of separated muscle and villi after microdissection.Results—NAT1 activity of all cytosols was greater than NAT2 activity. NAT1 and NAT2 activities correlated with the genotypes of NAT1 and NAT2 and with the levels of NAT1 staining determined by western blotting. The ratio of NAT1:NAT2 activities showed interindividual variations from 2 to 70. NAT1 antigenic activity was greater in villi than in muscle. NAT1 was detected along the length of the villi in the small intestine. In colon samples there was less NAT1 at the base of the crypts with intense staining at the tips.Conclusions—The interindividual variation in NAT1 and NAT2 in the colon could affect how individuals respond to exposure to specific NAT substrates including carcinogens and 5-ASA.
Tumour necrosis factor-α enhances intraepithelial lymphocyte proliferation and migration
Authors: Ebert E C 
Published: June 2010

Background—Tumour necrosis factor α (TNF-α) is a proinflammatory cytokine found in abundance in diseased intestine.Aims—The T cell production of TNF-α and the impact of this cytokine on intestinal T cell proliferation, migration, and cytotoxicity were studied.Methods—Intestinal lymphocytes from normal jejunum were used. TNF-α production in culture supernates was measured by enzyme linked immunosorbent assay (ELISA). Lymphocyte proliferation was measured using 3H thymidine uptake; migration, using transwell chambers; and cytotoxicity of HT-29 colon cancer cells, using the chromium-51 release assay.Results—TNF-α was produced mainly by the CD8+ T cells in the intraepithelial lymphocytes (IEL) and the CD4+ T cells in the lamina propria lymphocytes in response to CD2 stimulation: 478 (94) and 782 (136) pg/ml, respectively. TNF-α (1 ng/ml or greater) augmented proliferation of IEL in response to interleukin 2 (IL-2), IL-7, or antibody to CD3 due to increased activation that did not involve IL-2 production or receptor generation. Conversely, antibody to TNF-α reduced IEL proliferation in response to IL-2 or IL-7. TNF-α also induced calcium mobilisation and chemokinesis (by 2.8 (0.5) fold over spontaneous migration). TNF-α had no effect on lymphokine activated killer cell activity.Conclusions—TNF-α increases the proliferation and migration of IEL, which may expand their number in the epithelium.
Clonal analysis of isolated intestinal metaplastic glands of stomach using X linked polymorphism
Authors: Nomura S , Kaminishi M , Sugiyama K , Oohara T , Esumi H 
Published: June 2010

Background—Monoclonal precancerous cells undergo successive biochemical and genetic changes during the multistep process of carcinogenesis in the gastrointestinal tract. Despite a high association with intestinal-type stomach cancer (differentiated adenocarcinoma of the stomach), the role of intestinal metaplasia is unclear in stomach carcinogenesis.Aims—To study the clonality of intestinal metaplasia.Methods—The clonality of 86 single intestinal metaplastic glands isolated by EDTA treatment from gastrectomy specimens from patients with cancer were investigated. The methylation sensitive restriction enzyme HpaII and polymerase chain reaction (PCR) were used to detect a polymorphic human androgen receptor gene locus linked to an inactive X chromosome.Results—Forty one (48%) intestinal metaplastic glands were heterotypic (mixed cells of different allelic methylation) and 45 (52%) were homotypic (cell population of the same allelic methylation), while almost all the single pyloric glands were homotypic. Eleven of 13 intestinal metaplastic mucosae that were 6 mm in diameter contained glands that had originated from different cells. There were no strong relationships between clonal type and location or histological type of intestinal metaplasia.Conclusion—Intestinal metaplasia in general is not a lesion that arises or proceeds monoclonally.
cagA positive and negative Helicobacter pyloristrains are simultaneously present in the stomach of most patients with non-ulcer dyspepsia: relevance to histological damage
Authors: Figura N , Vindigni C , Covacci A , Presenti L , Burroni D , Vernillo R , Banducci T , Roviello F , Marrelli D , Biscontri M , Kristodhullu S , Gennari C , Vaira D 
Published: June 2010

Background/Aims—Infection with Helicobacter pylori strains harbouring the cagA gene (cagA+) is associated with an increased risk of developing peptic ulcer and gastric cancer. The aim of this study was to assess whether H pylori isolates with different cagA status were present in patients with non-ulcer dyspepsia, and whether a variable cagA status is relevant to histological gastric mucosal damage and glandular cell proliferation.Methods—Well separated H pyloricolonies (between 2 and 25) from primary plates, per gastric area, for each of 19 patients with non-ulcer dyspepsia were examined forcagA by hybridisation. Western blotting was used to examine both representative colonies for CagA expression and the patients’ sera for antibody response to CagA. Glandular gastric cell proliferation was assessed immunohistochemically.Results—Of the 747 colonies examined, 45.3% werecagA+. All colonies from four patients werecagA+, and all colonies from two patients werecagA−. In 13 patients (68%) both cagA+ andcagA− colonies were found. CagA expression of isolates corresponded to their cagA status. H pyloristrains with different CagA molecular masses were present in three patients. Results based on all 19 patients studied showed that the prevalence of cagA+ colonies in areas with mucosal atrophy associated or not with intestinal metaplasia (67.9%) was significantly higher than in normal mucosa (44.7%) and mucosa from patients with chronic gastritis (44.0%) (p< 0.001). High levels of cell proliferation were associated with histological atrophy with or without intestinal metaplasia, but not with the possession of cagA by organisms colonising the same mucosal sites.Conclusions—Most patients with non-ulcer dyspepsia are infected by both cagA+ and cagA−H pylori colonies. The cagA status of infecting organisms may play a role in the development of atrophy and intestinal metaplasia.
Mediation by NF-κB of cytokine induced expression of intercellular adhesion molecule 1 (ICAM-1) in an intestinal epithelial cell line, a process blocked by proteasome inhibitors
Authors: Jobin C , Hellerbrand C , Licato L L , Brenner D A , Sartor R B 
Published: June 2010

Background/aims—The gene promoter for the intercellular adhesion molecule ICAM-1 possesses binding sites for several transcriptional factors, including nuclear factor κB (NF-κB). The role of NF-κB in ICAM-1 gene regulation was therefore examined by using different proteasome inhibitors in tumour necrosis factor α (TNF-α) stimulated IEC-6 rat intestinal epithelial cells.Methods—ICAM-1 expression was analysed by enzyme linked immunosorbent assay (ELISA), reverse transcriptase polymerase chain reaction, and immunohistochemistry. Steady state levels of cytoplasmic IκB protein were evaluated by western blot, and nuclear translocation of NF-κB was determined by electrophoretic mobility shift assay and immunofluorescence staining. Cell adhesion was assayed by measuring the binding of fluorescence labelled MOLT-4 cells.Results—TNF-α induced ICAM-1 mRNA and protein expression in IEC-6 cells, which was followed by increased adhesion of MOLT-4 lymphocytes. Blocking TNF-α induced IκBα degradation with proteasome inhibitors reduced TNF-α induced NF-κB activation and ICAM-1 gene induction and notably decreased MOLT-4 cell adhesion without affecting Jun N-terminal kinase (JNK/SAPK) activity or de novo protein synthesis.Conclusion—TNF-α induction of ICAM-1 expression is mediated by the transcription factor NF-κB and can be inhibited by blocking IκBα degradation. Thus the IκB/NF-κB system is a promising target for pharmacological modulation of the expression of adhesion molecules and other inflammatory genes in the intestine.
Anti-Saccharomyces cerevisiae mannan antibodies combined with antineutrophil cytoplasmic autoantibodies in inflammatory bowel disease: prevalence and diagnostic role
Authors: Quinton J-F , Sendid B , Reumaux D , Duthilleul P , Cortot A , Grandbastien B , Charrier G , Targan S R , Colombel J-F , Poulain D 
Published: June 2010

Background—Perinuclear antineutrophil cytoplasmic autoantibodies (pANCA) are a well recognised marker for ulcerative colitis. Antibodies to oligomannosidic epitopes of the yeastSaccharomyces cerevisiae (ASCA) are a new marker associated with Crohn’s disease.Aims—To assess the value of detecting pANCA and/or ASCA for the diagnosis of ulcerative colitis and Crohn’s disease.Methods—Serum samples were obtained from 100 patients with Crohn’s disease, 101 patients with ulcerative colitis, 27 patients with other miscellaneous diarrhoeal illnesses, and 163 healthy controls. Determination of pANCA and ASCA was performed using the standardised indirect immunofluorescence technique and an ELISA, respectively.Results—The combination of a positive pANCA test and a negative ASCA test yielded a sensitivity, specificity, and positive predictive value of 57%, 97%, and 92.5% respectively for ulcerative colitis. The combination of a positive ASCA test and a negative pANCA test yielded a sensitivity, specificity, and positive predictive value of 49%, 97%, and 96% respectively for Crohn’s disease. Among patients with miscellaneous non-inflammatory bowel disorders, three were ASCA positive and two were pANCA positive. One control was ASCA positive. The presence of ASCA in patients with Crohn’s disease was associated with small bowel involvement.Conclusion—ASCA and pANCA are strongly associated with Crohn’s disease and ulcerative colitis, respectively. Combination of both tests could help the diagnosis of inflammatory bowel disease.
Symptoms and visceral perception in severe functional and organic dyspepsia
Authors: Mertz H , Fullerton S , Naliboff B , Mayer E A 
Published: June 2010

Background—Hypersensitivity of gastric afferent pathways may play an aetiological role in symptoms of functional dyspepsia.Aims—To determine whether patients with severe organic dyspepsia (associated with tissue irritation/injury) and those with functional dyspepsia (no detectable tissue irritation) differ in their perception of gastric distension and whether this difference is reflected in differences in their gastrointestinal and psychological symptoms.Methods—Perceptual thresholds, referral patterns, and gastrointestinal and psychological symptoms were compared in 23 patients with functional dyspepsia, 10 organic dyspeptics, and 15 healthy controls.Results—Fifteen (65%) functional dyspeptics and no organic dyspeptics had reduced perceptual thresholds for fullness, discomfort, or pain (odds ratio (OR) 19.56, 95% confidence interval (CI) 1.95 to 476.09, p=0.0017). Either reduced perceptual thresholds or altered referral was found in 20 (87%) functional dyspeptics and four (20%) organic dyspeptics (OR 10.0, 95% CI 1.34 to 89.54, p=0.014). During sham distension fullness, discomfort and pain were reported by healthy controls, organic dyspeptics, and functional dyspeptics. A sham response of pain but no other sensation was more frequent among functional dyspeptics (43%) than healthy controls (7%) (OR 10.77, 95% CI 1.10 to 257.35, p=0.026). Gastrointestinal and psychological symptoms and gastric compliance were similar in the functional and organic groups.Conclusions—Alterations in the perception of gastric distension distinguishes between functional and organic dyspepsia, while symptoms do not. A total of 87% of functional dyspeptics studied had evidence of altered visceral afferent function. In this study population, psychological abnormalities or changes in compliance did not explain the findings.