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41.
To characterize posttreatment recurrence of Helicobacter pylori in Peru, 192 adults with H. pylori-positive gastric biopsy specimens were monitored by (14)C-Urea breath test, after eradication of H. pylori by use of amoxicillin, clarithromycin, and omeprazole. The cumulative risk of recurrence at 18 months was 30.3% (95% confidence interval, 21.4%-39.3%). Randomly amplified polymorphic DNA patterns and DNA sequence data established that, among 28 pairs of H. pylori isolates from pretreatment and recurrent infections, 6 (21%) were genetically similar, suggesting recrudescence of the previous infection, and 22 (79%) were different, suggesting reinfection with a new strain that differed from that involved in the initial infection. Eating mainly outside of the home was a risk factor for infection with a new strain (adjusted relative risk [RR], 5.07), whereas older age was a protective factor (adjusted RR, 0.20). Although an increase in the anti-H. pylori IgG antibody titer corresponded to recurrence, pretreatment and recurrent infections were similar with respect to quantitative culture colony counts and histologic characteristics, suggesting that neither prior eradication nor the memory immune response measurably alters the risk or burden of recurrent infection. Although eradication with antibiotics was successful, the high rate of reinfection suggests that treatment is unlikely to have a lasting public health effect in this setting.  相似文献   
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Epigenetic alterations alone or in combination with genetic mechanisms play a key role in brain tumorigenesis. Glioblastoma is one of the most common, lethal and poor clinical outcome primary brain tumors with extraordinarily miscellaneous epigenetic alterations profile. The aim of this study was to investigate new potential prognostic epigenetic markers such as AREG, HOXA11, hMLH1, NDRG2, NTPX2 and Tes genes promoter methylation, frequency and value for patients outcome. We examined the promoter methylation status using methylation-specific polymerase chain reaction in 100 glioblastoma tissue samples. The value for clinical outcome was calculated using Kaplan–Meier estimation with log-rank test. DNA promoter methylation was frequent event appearing more than 45 % for gene. AREG and HOXA11 methylation status was significantly associated with patient age. HOXA11 showed the tendency to be associated with patient outcome in glioblastomas. AREG gene promoter methylation showed significant correlation with poor patient outcome. AREG methylation remained significantly associated with patient survival in a Cox multivariate model including MGMT promoter methylation status. This study of new epigenetic targets has shown considerably high level of analyzed genes promoter methylation variability in glioblastoma tissue. AREG gene might be valuable marker for glioblastoma patient survival prognosis, however further analysis is needed to clarify the independence and appropriateness of the marker.  相似文献   
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Azobenzene photoswitches were recently reported to control the activity of neural cells and heart beat in leeches. Here, we report photocontrol of excitation of cultured cardiomyocytes that have been made light sensitive by using the addition of azobenzene trimethylammonium bromide (AzoTAB). The trans-isomer of AzoTAB reversibly suppresses spontaneous activity and propagation of excitation waves, whereas the cis-isomer has no detectable effect on the electrical properties of cardiomyocytes. Photoisomerization of AzoTAB was achieved by switching the illumination wavelength, λ, from ~440 nm (trans-isomer) to ~350 nm (cis-isomer). Simultaneous irradiation at two wavelengths with properly chosen intensities allowed for dynamic control of the cis-isomer/trans-isomer ratio and the level of excitability from normal to fully unexcitable. Experiments were conducted by using AzoTAB-treated confluent monolayers of neonatal rat cardiomyocytes. Excitation waves were monitored by using the Ca2+-sensitive fluorescent dye Fluo-4. By projecting two-wavelength illumination patterns onto otherwise uniform cell layers, we were able to create excitable networks with the desired topology, dimensions, and functional properties. The present article discusses potential applications of this technique for the analysis of complex patterns of electrical excitation and cardiac arrhythmias.  相似文献   
44.
AIM OF THE STUDY. To evaluate the tooth brushing skills and the prevalence of dental caries as well as its intensity in relation to oral hygiene skills among 4 - 6-year-old children. MATERIAL AND METHODS. The cross-sectional study was performed from November 16, 2009 to January 12, 2010. 235 children (4 - 6-year old) were randomly selected from kindergartens in Plung? and Jonava in Lithuania. The results of study were registered in the special forms prepared in accordance with the recommendations of WHO. Parents of the children were asked to fill in the questionnaires. RESULTS. The results of the study show that 91% (Plung?) and 90% (Jonava) of 4 - 6-year-old children have caries in their primary teeth. The prevalence of caries is different in relation to age: 78.7% of 4-year-old children, 97.3% of 5-year-old children, and 95.3% of 6-year-old children. The intensity of caries is as follows: 4.9 (SN=±4.9), 7.5 (SN=±4.5), and 8.2 (SN=±4.7). CONCLUSIONS. There is the high prevalence of caries, particularly of not treated forms, among 4 - 6-year-old children. The oral hygiene index is just satisfactory.  相似文献   
45.
An infant with hypoplastic left heart syndrome (HLHS) presented with complete heart block and severe myocardial dysfunction requiring ECMO support due to complete left main coronary artery (LMCA) thrombosis. Current guidelines for managing coronary artery thrombosis in infants with single ventricle physiology are inadequate. We describe successful LMCA and branch recanalization via intra coronary infusion of recombinant tissue plasminogen activator and discuss management of acute coronary thrombosis in children with single ventricle physiology.  相似文献   
46.
Myofibroblastoma of the breast is a rare benign mesenchymal tumor. The literature describes relatively few cases of this type of tumor. We report on a new case of myofibroblastoma in a 65-year old man successfully managed at our institution. The purpose of this case report is to highlight characteristics and differential diagnosis of this rare neoplasm.  相似文献   
47.
Activated pancreatic stellate cells (PSC) play a major role in the development of chronic pancreatitis. Flavonoids (C‐3‐O‐G) theoretically may have potential to suppress activated PSC. The aim of our study was to determine the ability of C‐3‐O‐G to invert synthetic and metabolic activity of alcohol stimulated human pancreatic stellate cells (hPSC). In the present study we demonstrate that treatment with C‐3‐O‐G decreased proliferation rate of ethanol activated hPSC by 51%. Synthesis of extracellular matrix proteins in activated hPSC was markedly inhibited, as shown by reduced levels of collagen I and fibronectin expression. The decrease of secretion of fibronectin by 33% and in collagen I‐25% in ethanol activated and C‐3‐O‐G treated hPSC was observed. Moreover, treatment of ethanol activated hPSC with C‐3‐O‐G resulted in the decrease of oxygen consumption rate by 44% and reduced levels of ATP synthesis (i.e. energy production) by 41%. Hence, the effects of C‐3‐O‐G on ethanol activated hPSC may provide new insights for the use of anthocyanins as anti‐fibrogenic agents in treatment and/or prevention of pancreatic fibrosis. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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The development of transgenic mouse lines that selectively label a subset of neurons provides unique opportunities to study detailed neuronal morphology and morphological changes under experimental conditions. In the present study, a mouse line in which a small number of retinal ganglion cells (RGCs) express yellow fluorescent protein (YFP) under control of the Thy-1 promoter was used (Feng et?al., 2000). We characterized the number, distribution by retinal region and eccentricity of YFP-labeled RGCs using fluorescence microscopy and Stereo Investigator software (MicroBrightField, VT, USA). Then, we captured images of 4-6?YFP-expressing RGCs from each of 8 retinal regions by confocal microscopy, producing 3-dimensional and flattened data sets. A new semi-automated method to quantify the soma size, dendritic length and dendritic arbor complexity was developed using MetaMorph software (Molecular Devices, PA, USA). Our results show that YFP is expressed in 0.2% of all RGCs. Expression of YFP was not significantly different in central versus peripheral retina, but there were higher number of YFP-expressing RGCs in the temporal quadrant than in the nasal. By confocal-based analysis, 58% of RGCs expressing YFP did so at a high level, with the remainder distributed in decreasing levels of brightness. Variability in detailed morphometric parameters was as great between two fellow retinas as in retinas from different mice. The analytic methods developed for this selective YFP-expressing RGC model permit quantitative comparisons of parameters relevant to neuronal injury.  相似文献   
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