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81.
Gastric perception thresholds are low and sensory neuropeptide levels high in helicobacter pylori-positive functional dyspepsia 总被引:7,自引:0,他引:7
Mönnikes H van der Voort IR Wollenberg B Heymann-Monnikes I Tebbe JJ Alt W Arnold R Klapp BF Wiedenmann B McGregor GP 《Digestion》2005,71(2):111-123
BACKGROUND AND AIMS: In functional dyspepsia (FD) decreased perception levels can be shown on gastric distension. Substance P (SP) and calcitonin gene-related peptide (CGRP) are involved in the sensitization of afferent neuronal pathways due to chronic inflammation. The role of Helicobacter pylori-induced gastric mucosal inflammation in the pathogenesis of FD is controversial. The aim of this study was to assess whether FD patients have altered mucosal concentrations of CGRP and SP, and to investigate whether this is associated with visceral hypersensitivity or H. pylori infection. METHODS: Gastrointestinal symptoms, H. pylori status, perception thresholds at gastric balloon distension, and gastric mucosal concentrations of CGRP and SP were determined in 13 FD patients and 18 healthy controls (HC). RESULTS: In H. pylori-positive FD patients discomfort and pain thresholds on gastric distension were lower compared to other groups. Antral mucosal levels of CGRP and SP were higher in H. pylori-positive subjects. In FD significantly negative correlations between discomfort and pain thresholds and antral mucosal concentrations of CGRP and SP were observed. CONCLUSIONS: In FD low perception thresholds on gastric distension are associated with high levels of CGRP and SP in the antrum, suggesting that sensory neuropeptides are involved in FD pathophysiology. 相似文献
82.
Ivo Rudolf Oldřich Šebesta Jan Mendel Lenka Betášová Eva Bocková Petra Jedličková Kristýna Venclíková Hana Blažejová Silvie Šikutová Zdeněk Hubálek 《Parasitology research》2014,113(12):4663-4667
The surveillance of vectors for arthropod-borne pathogens is nowadays an important tool in surveillance programmes throughout Europe. Whereas many studies have been performed to screen arthropods for viruses or bacterial pathogens, only limited information is available concerning the geographical distribution and vector range of pathogenic filariae in Central Europe. To consider the prevalence of filarial parasites in mosquito vectors, we performed a molecular survey of mosquitoes for filarial DNA. Mosquito collection was conducted at six study sites in the South Moravian region (Czech Republic) close to the borders with Slovakia and Austria from 2009 to 2011. Molecular screening of mosquitoes was conducted using conventional PCR with primers designed to amplify the mitochondrial cytochromoxidase subunit I gene as well as the partial 5.8S ribosomal RNA gene. A total of 13,222 mosquitoes belonging to six species were captured and distributed into 237 pools with different numbers of individuals. Overall, four pools were positive for Dirofilaria repens (a minimum infection rate 0.03 %) at two study sites (both natural and urban). Another filarial parasite detected during a study into Aedes vexans mosquitoes revealed the closest homology to Setaria spp. We detected specific D. repens DNA in Ae. vexans mosquitoes for the first time in the Czech Republic and confirmed the circulation of Dirofilaria spp. in a natural focus of infection providing an epidemiological link between autochthonous canine cases and mosquito vectors in the area studied. 相似文献
83.
Pascale Mustapha Isabelle Paris Magali Garcia Cong Tri Tran Julie Cremniter Martine Garnier Jean-Pierre Faure Thierry Barthes Ivo G. Boneca Franck Morel Jean-Claude Lecron Christophe Burucoa Charles Bodet 《Infection and immunity》2014,82(7):2881-2889
Helicobacter pylori infection systematically causes chronic gastric inflammation that can persist asymptomatically or evolve toward more severe gastroduodenal pathologies, such as ulcer, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. The cag pathogenicity island (cag PAI) of H. pylori allows translocation of the virulence protein CagA and fragments of peptidoglycan into host cells, thereby inducing production of chemokines, cytokines, and antimicrobial peptides. In order to characterize the inflammatory response to H. pylori, a new experimental protocol for isolating and culturing primary human gastric epithelial cells was established using pieces of stomach from patients who had undergone sleeve gastrectomy. Isolated cells expressed markers indicating that they were mucin-secreting epithelial cells. Challenge of primary epithelial cells with H. pylori B128 underscored early dose-dependent induction of expression of mRNAs of the inflammatory mediators CXCL1 to -3, CXCL5, CXCL8, CCL20, BD2, and tumor necrosis factor alpha (TNF-α). In AGS cells, significant expression of only CXCL5 and CXCL8 was observed following infection, suggesting that these cells were less reactive than primary epithelial cells. Infection of both cellular models with H. pylori B128ΔcagM, a cag PAI mutant, resulted in weak inflammatory-mediator mRNA induction. At 24 h after infection of primary epithelial cells with H. pylori, inflammatory-mediator production was largely due to cag PAI substrate-independent virulence factors. Thus, H. pylori
cag PAI substrate appears to be involved in eliciting an epithelial response during the early phases of infection. Afterwards, other virulence factors of the bacterium take over in development of the inflammatory response. Using a relevant cellular model, this study provides new information on the modulation of inflammation during H. pylori infection. 相似文献
84.
Izabela Strużyńska‐Piron Johan Loccufier Luc Vanmaele Ivo F. J. Vankelecom 《Macromolecular chemistry and physics.》2014,215(7):614-623
Polysulfone‐based membranes with excellent chemical resistance and a wet thickness up to 200 μm are obtained via UV curing of unmodified polymers after careful tuning of the photoinitiating system and the crosslinker structure. Combinations of photoinitiator and crosslinker are studied in depth, followed by a characterization of the formed macromolecular structure. The performance of the resulting membranes is then evaluated through long‐term immersion in solvents. Classical depth‐curing acyl phosphine oxide‐based photoinitiators in combination with a pentaacrylate crosslinker are found to be the optimal system.
85.
1q gain is a frequent finding in preoperatively treated Wilms tumors,but of limited prognostic value for risk stratification in the SIOP2001/GPOH trial 下载免费PDF全文
86.
87.
Jo?o Luiz Langer Manica M?nica Scott Borges Rogério Fachel de Medeiros Leandro dos Santos Fischer Gabriel Broetto Raul Ivo Rossi Filho 《Arquivos brasileiros de cardiologia》2014,103(2):131-137
Background
The use of three-dimensional rotational angiography (3D-RA) to assess patients with congenital heart diseases appears to be a promising technique despite the scarce literature available.Objectives
The objective of this study was to describe our initial experience with 3D-RA and to compare its radiation dose to that of standard two-dimensional angiography (2D-SA).Methods
Between September 2011 and April 2012, 18 patients underwent simultaneous 3D-RA and 2D-SA during diagnostic cardiac catheterization. Radiation dose was assessed using the dose-area-product (DAP).Results
The median patient age and weight were 12.5 years and 47.5 Kg, respectively. The median DAP of each 3D-RA acquisition was 1093µGy.m2 and 190µGy.m2 for each 2D-SA acquisition (p<0.01). In patients weighing more than 45Kg (n=7), this difference was attenuated but still significant (1525 µGy.m2 vs.413µGy.m2, p=0.01). No difference was found between one 3D-RA and three 2D-SA (1525µGy.m2 vs.1238 µGy.m2, p = 0.575) in this population. This difference was significantly higher in patients weighing less than 45Kg (n=9) (713µGy.m2 vs.81µGy.m2, P = 0.008), even when comparing one 3D-RA with three 2D-SA (242µGy.m2, respectively, p<0.008). 3D-RA was extremely useful for the assessment of conduits of univentricular hearts, tortuous branches of the pulmonary artery, and aorta relative to 2D-SA acquisitions.Conclusions
The radiation dose of 3D-RA used in our institution was higher than those previously reported in the literature and this difference was more evident in children. This type of assessment is of paramount importance when starting to perform 3D-RA. 相似文献88.
Scherptong RW Henkens IR Kapel GF Swenne CA van Kralingen KW Huisman MV Schuerwegh AJ Bax JJ van der Wall EE Schalij MJ Vliegen HW 《Journal of electrocardiology》2012,45(3):312-318
PurposeThe aim of this study was to investigate the use of the electrocardiogram-derived ventricular gradient, projected on the x-axis (VGx), for detection of pulmonary hypertension (PH) and for prediction of all-cause mortality in PH patients.MethodsIn patients referred for PH screening (n = 216), the VGx was calculated semiautomatically from the electrocardiogram and was defined as abnormal when less than 24 mV·ms. The VGx of PH patients was compared with the VGx of patients without PH. The association between a reduced VGx and mortality was investigated in PH patients.ResultsPatients with PH (n = 117) had a significantly reduced VGx: 14 ± 27 vs 45 ± 23 mV·ms, P < .001. Furthermore, a severely reduced VGx (<0 mV·ms) was associated with increased mortality in PH patients: hazard ratio, 1.025 (95% confidence interval, 1.006-1.045; P = .012) per mV·ms VGx decrease.ConclusionReduced VGx is associated with the presence of PH and, more importantly, within PH patients, a severely reduced VGx predicts mortality. 相似文献
89.
90.
To gain more insight into the consequences of curing contraction within the tooth cavity, we assessed the margin behavior of 12 contemporary restorative systems in class V restorations with margins located on enamel and dentin after mechanical loading and water storage. Mixed class V cavities were prepared on extracted human molars and restored using five etch and rinse and seven self-etch adhesive systems with their corresponding composites. Marginal adaptation was evaluated by using a computer-assisted quantitative marginal analysis in a scanning electron microscope (SEM) on epoxy replicas before, after thermal and mechanical stressing and after 1 year of water storage. The interactions of "testing conditions", "adhesive-composite combination" and "tooth substrate" with "marginal adaptation" were evaluated by two-way ANOVA. Fatigue, stress and storage conditions had significant effects on the marginal adaptation. Only two groups (Optibond FL and G Bond) presented equal percentages of marginal adaptation on enamel and dentin; in the other groups, the rate of degradation was product dependent. All materials tested showed a distinct behavior on enamel and dentin. In addition to mechanical resistance and long-term stability, differences within materials also exist in their ability to simultaneously bond to enamel and dentin. 相似文献