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Antibiotic Resistance of <i>Helicobacter pylori</i>and Eradication Rate in j.panese Pediatric Patients

Advances in Microbiology 2017年第4期7卷 241-252页

作者： Tamaki Ikuse Yo Aoyagi Naho Obayashi Keisuke j.mbo Takahiro Kudo Yoshikazu Ohtsuka Thomas G. Blanchard steven j. czinn Toshiaki Shimizu Department of Pediatric and Adolescent Medicine Juntendo University Graduate School of Medicine Tokyo Japan Department of Pediatrics University of Maryland School of Medicine Baltimore USA

Helicobacter pylori (H. pylori) eradication rates achieved with a proton pump inhibitor (PPI), amoxicillin and clarithromycin have recently decreased to about 75% because of the increase in clarithromycin resistance in j.pan. In the present study, H. pylori resistance rates against clarithromycin, amoxicillin and metronidazole were investigated in pediatric patients and eradication rates were evaluated when tailored antibiotics regimens based on antibiotic sensitivity data were used. We isolated H. pylori endoscopically from 77 pediatric patients suffering from abdominal symptoms. The susceptibility tests of H. pylori strains to clarithromycin, amoxicillin and metronidazole were examined and eradication therapy was tailored using the appropriate antibiotics. Seventy-seven patients were treated with a mean age of 12.16 ± 3.34 years (range, 4.92-19.75) consisting of 40 males and 37 females. The average resistance rates between 1998 and 2016 to clarithromycin, amoxicillin and metronidazole were 54.5% (42 of 77), 6.5% (5 of 77) and 5.2% (4 of 77) respectively. The prevalence of clarithromycin resistance increased significantly over time to reach 88.9% by 2013-2016. Successful eradication rates using tailored antibiotic treatment was 93.8% (61 of 65). Clarithromycin-based eradication therapy rate reached 92.6% against clarithromycin-sensitive strains. Metronidazole-based initial eradication therapy also had a high successful rate (97.0%) to clarithromycin-resistant strains. Although high rates of clarithromycin resistant H. pylori reaching about 90% were observed in j.panese children, tailored eradication therapy using the appropriate antibiotic agents were highly successful. H. pylori sensitivity testing and eradication therapy with appropriate antibacterial agents may contribute to accomplishment of high initial eradication rates and consequently reducing the incidence of developing gastric cancer.

关键词： Resistance Eradication Rate Susceptibility Test Clarithromycin Metronidazole

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A Retrospective Analysis of Three Non-Invasive Tests for Initial Diagnosis of <i>Helicobacter pylori</i>Infection in Children

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Advances in Microbiology 2017年第4期7卷 253-264页

作者： Tamaki Ikuse Takahiro Kudo Naho Obayashi Keisuke j.mbo Yo Aoyagi Yoshikazu Ohtsuka Thomas G. Blanchard steven j. czinn Toshiaki Shimizu Department of Pediatric and Adolescent Medicine Juntendo University Graduate School of Medicine Tokyo Japan Department of Pediatrics University of Maryland School of Medicine Baltimore USA

Proper diagnosis in the pediatric population is required to eradicate Helicobacter pylori (H. pylori) and prevent gastric cancer. Our aim was to assess the performance of non-invasive tests to diagnose H. pylori infection in pediatric patients. A retrospective analysis was performed on 141 pediatric patients requiring endoscopic evaluation and diagnostic tests for H. pylori infection to define the cause of abdominal symptoms. Non-invasive tests included the 13C-urea breath test (UBT), a monoclonal stool antigen test using enzyme-linked immuno-sorbent assay (mSAT), and a serum immunoglobulin G antibody test using antigens derived from j.panese individuals (S-Ab). This study investigated sensitivity, specificity, likelihood ratios for a positive and a negative test (LR+ and LR-), and accuracy of non-invasive tests, in comparison with invasive tests. Eighty two of 141 patients (58%) were recognized as H. pylori positive by invasive methods. When UBT, mSAT or S-Ab were analyzed, all were found to be effective over 94% accurate. Specificity ranged between 86.7% and 95.8%, and sensitivity ranged between 93.8% and 97.1%. When subj.cts were stratified into three distinct age groups, the best performance was achieved for 1-6 years old with mSAT at 100% for sensitivity, specificity, and accuracy. S-Ab yielded the best results for children 7-12 years old and the UBT test performed best for 13-18 years old. These results demonstrate the utility of UBT, mSAT, and S-Ab non-invasive tests in diagnosing H. pylori but suggest that certain tests may be optimal for children of distinct ages. Three non-invasive tests, UBT, mSAT and S-Ab showed sufficient sensitivity, specificity and accuracy for the initial diagnosis of H. pylori infection among pediatric patients. Non-invasive tests may contribute to achieving minimum invasive diagnosis with combining with a histological test and a culture test in children.

关键词： Accuracy Non-Invasive Tests Urea Breath Test Stool Antigen Test Serum Antibody Test

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Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

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Science China Earth Sciences 2025年第1期68卷 74-93页

作者： Ye YANG steven A.BINNIE Sheng XU Cong-Qiang LIU Tibor j.DUNAI Institute of Surface-Earth System Science School of Earth System Science Tianjin University Institute of Geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

关键词： 10Be-derived denudation rate Climate change Tectonic uplift Topographic gradient Asian mountains

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VARIABLE STEP-SIZE IMPLICIT-EXPLICIT LINEAR MULTISTEP METHODS FOR TIME-DEPENDENT PARTIAL DIFFERENTIAL EQUATIONS

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j.urnal of Computational Mathematics 2008年第6期26卷 838-855页

作者： DongWang steven j. Ruuth Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign B231 Newmark Civil Engineering Laboratory Urbana IL 61801 USA Department of Mathematics Simon Fraser University Burnaby BC Canada V5A 1S6

Implicit-explicit （IMEX） linear multistep methods are popular techniques for solving partial differential equations （PDEs） with terms of different types. While fixed timestep versions of such schemes have been developed and studied, implicit-explicit schemes also naturally arise in general situations where the temporal smoothness of the solution changes. In this paper we consider easily implementable variable step-size implicit-explicit （VSIMEX） linear multistep methods for time-dependent PDEs. Families of order-p, pstep VSIMEX schemes are constructed and analyzed, where p ranges from 1 to 4. The corresponding schemes are simple to implement and have the property that they reduce to the classical IMEX schemes whenever constant time step-sizes are imposed. The methods are validated on the Burgers＇ equation. These results demonstrate that by varying the time step-size, VSIMEX methods can outperform their fixed time step counterparts while still maintaining good numerical behavior.

关键词： Implicit-explicit (IMEX) linear multistep methods Variable step-size Zero-stability Burgers' equation.

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Mitogen-activated protein kinases mediate the oxidative burst and saponin synthesis induced by chitosan in cell cultures of Panax ginseng

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Science China(Life Sciences) 2004年第4期47卷 303-312页

作者： steven j. NEILL Centre for Research in Plant Science University of the West of England Bristol Coldharbour Lane Bristol BS16 1QY United Kingdom

Chitosan (CHN) specially induced the activities of 39 kD and 42 kD protein kinases in ginseng cells, which could be suppressed by an inhibitor of mitogen-activated protein kinase (MAPK) pathway, PD98059. The immunoprecipitation (IP) using MAPK antibody or kinase assay in vitro also showed that CHN-induced 42 kD and 39 kD protein kinases belonged to the MAPK family. PD98059 suppressed CHN-induced transcriptions of ginseng squalene synthase and ginseng squalene epoxidase genes (gss and gse), CHN-induced accumulation of β-Amyrin synthase (β-AS) and synthesis of saponin. These results showed that CHN-induced activities of MAPKs were necessary for the CHN-induced saponin synthesis. EGTA and LaCl3 suppressed CHN-induced 39 kD and 42 kD MAPK activities. Ruthenium red (RR) could suppress CHN-induced 39 kD activity. All of them suppressed CHN-induced saponin synthesis. These results indicated that CHN-induced increment of cytosolic calcium was necessary for CHN-induced saponin synthesis. PD98059 also suppressed CHN-induced oxidative burst (including the increment of activity of plasma membrane NADPH oxidase and production of H2O2), but diphenylene iodonium (DPI), dimethylthiourea (DMTU) and 2,5-dihydroxycinnamic acid methyl ester (DHC) could not suppress CHN-induced MAPK activities, which indicated that MAPK was possibly function upstream of CHN-induced oxidative burst. Keywords mitogen-activated protein kinase - chitosan - saponin

关键词： mitogen-activated protein kinase,chitosan,saponin.

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NUMERICAL SIMULATION OF THE XZ TAURI SUPERSONIC ASTROPHYSICAL j.T

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Acta Mathematica Scientia 2009年第6期29卷 1677-1683页

作者： Carl L. Gardner steven j. Dwyer School of Mathematical and Statistical Sciences Arizona State University Tempe AZ 85287 USA

Computational gas dynamical simulations using the WENO-LF method are applied to modeling the high Mach number astrophysical j.t XZ Tauri, including the effects of radiative cooling. Mach 55 simulations of the pulsed proto-j.t are presented and analyzed in terms of interacting nonlinear waves： terminal Mach disks, bow shocks, and Meshkov-Richtmyer instabilities of the leading j.t contact boundary.

关键词： astrophysical j.ts ENO. method gas dynamics

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Closed 3-stop Center and Periphery in Graphs

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Acta Mathematica Sinica,English Series 2012年第3期28卷 439-452页

作者： Linda EROH Ralucca GERA steven j. WINTERS Department of Mathematics University of Wisconsin Oshkosh Department of Applied Mathematics Naval Postgraduate School

A delivery person must leave the central location of the business, deliver packages at a number of addresses, and then return. Naturally, he/she wishes to reduce costs by finding the most efficient route. This motivates the following： Given a set of k distinct vertices S = {x1, x2,..., xk } in a simple graph G, the closed k-stop-distance of set S is defined to be

关键词： Central appendage number peripheral appendage number Steiner distance

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Scales of snow depth variability in high elevation rangeland sagebrush

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Frontiers of Earth Science 2017年第3期11卷 469-481页

作者： Molly E. TEDESCHE steven R. FASSNACHT Paul j. MEIMAN Watershed Science Department of Ecosystem Science and Sustainability Colorado State University Fort Collins CO 80523-1476 USA Intemational Arctic Research Center Water & Environmental Research Center Institute of Northern Engineering University of Alaska Fairbanks Fairbanks AK 99775 USA Cooperative Institute for Research in the Atmosphere Fort Collins CO 80523-1375 USA Natural Resources Ecology Laboratory Fort Collins CO 80523-1499 USA Abt. Kartographie GIS & Femerkundung Geographisches Institut Georg-August-Universitat Gottingen 37077 Gottingen Germany Rangeland Ecosystem Science Department of Forest and Rangeland Stewardship Colorado State University Fort Collins CO 80523 USA

In high elevation semi-arid rangelands, sage- brush and other shrubs can affect transport and deposition of wind-blown snow, enabling the formation of snowdrifts. Datasets from three field experiments were used to investigate the scales of spatial variability of snow depth around big mountain sagebrush （Artemisia tridentata Nutt.） at a high elevation plateau rangeland in North Park, Colorado, during the winters of 2002, 2003, and 2008. Data were collected at multiple resolutions （0.05 to 25 m） and extents （2 to 1000 m）. Finer scale data were collected specifically for this study to examine the correlation between snow depth; sagebrush microtopogra- phy, the ground surface, and the snow surface, as well as the temporal consistency of snow depth patterns. Vario- grams were used to identify the spatial structure and the Moran＇s I statistic was used to determine the spatial correlation. Results show some temporal consistency in snow depth at several scales. Plot scale snow depth variability is partly a function of the nature of individual shrubs, as there is some correlation between the spatial structure of snow depth and sagebrush, as well as between the ground and snow depth. The optimal sampling resolution appears to be 25-cm, but over a large area, this would require a multitude of samples, and thus a random stratified approach is recommended with a fine measurement resolution of 5-cm.

关键词： snow hydrology high elevation rangelands,spatial statistics variograms snow pack spatial variability,snow drifts

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Influence of free water availability on a desert carnivore and herbivore

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Current Zoology 2017年第2期63卷 121-129页

作者： Bryan M. KLUEVER Eric M. GESE steven j. DEMPSEY Department of Wildland Resources Utah State University Logan UT 84322-5230 USA United States Department of Agriculture Animal and Plant Health Inspection Service Wildlife Services National Wildlife Research Center Department of Wildland Resources Utah State University Logan UT 84322-5230 USA

Anthropogenic manipulation of finite resources on the landscape to benefit individual species or communities is commonly employed by conservation and management agencies. One such action in arid regions is the construction and maintenance of water developments （i.e., wildlife guzzlers） adding free water on the landscape to buttress local populations, influence animal movements, or af- fect distributions of certain species of interest. Despite their prevalence, the utility of wildlife guzzlers remains largely untested. We employed a before-after control-impact （BACI） design over a 4-year period on the US Army Dugway Proving Ground, Utah, USA, to determine whether water avaij.bility at wildlife guzzlers influenced relative abundance of black-tailed j.ckrabbits Lepus californicus and relative use of areas near that resource by coyotes Canis latrans, and whether coyote visitations to guzzlers would decrease following elimination of water. Eliminating water availability at guzzlers did not influence j.ckrabbit relative abundance. Coyote relative use was impacted by water availability, with elimination of water reducing use in areas associated with our treatment, but not with areas associated with our control. Visitations of radio-collared coyotes to guzzlers declined nearly 3-fold following elimination of water. Our study provides the first evidence of a potential direct effect of water sources on a mammalian carnivore in an arid environment, but the ecological relevance of our finding is debatable. Future investigations aimed at determining water effects on terrestrial mam- mals could expand on our findings by incorporating manipulations of water availability, obtaining absolute estimates of population parameters and vital rates and incorporating fine-scale spatiotem- poral data.

关键词： arid black-tailed j.ckrabbit Canis latrans coyote Lepus cafifornicus.

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Mate choice decisions by searchers

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Current Zoology 2013年第2期59卷 184-199页

作者： Daniel D. WIEGMANN Lisa M. ANGELONI steven M. SEUBERT j. GordonWADE Department of Biological Sciences and j. P. Scott Center for Neuroscience Mind and Behavior Bowling Green State University Bowling Green OH 43403 USA Department of Biology Colorado State University Fort Collins CO 80523 USA Department of Mathematics and Statistics Bowling Green State University Bowling Green OH 43403 USA

For more than two decades rudimentary versions of the fixed sample and sequential search strategies have provided the primary theoretical foundation for the study of mate choice decisions by searchers. The theory that surrounds these models has expanded markedly over this time period. In this paper, we review and extend results derived from these models, with a focus on the empirical analysis of searcher behavior. The basic models are impractical for empirical purposes because they rely on the as- sumption that searchers--and, for applied purposes, researchers--assess prospective mates based on their quality, the fitness consequences of mate choice decisions. Here we expound versions of the models that are more empirically useful, reformulated to reflect decisions based on male phenotypic characters. For some organisms, it may be possible to use preference functions to de- rive predictions from the reformulated models and thereby avoid difficulties associated with the measurement of male quality per se. But predictions derived from the two models are difficult to differentiate empirically, regardless of how the models are formu- lated. Here we develop ideas that illustrate how this goal might be accomplished. In addition, we clarify how the variability of male quality should be evaluated and we extend what is known about how this variability influences searcher behavior under each model. More general difficulties associated with the empirical study of mate choice decisions by searchers are also discussed [Current Zoology 59 （2）： 184-199, 2013].

关键词： Dispersive order Fixed sample strategy Mate choice Preference functions Sequential search Stochastic dominance

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