147 research outputs found

    Enterococcus faecalis utilizes maltose by connecting two incompatible metabolic routes via a novel maltose-6-P phosphatase (MapP)

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    Similar to Bacillus subtilis, Enterococcus faecalis transports and phosphorylates maltose via a phosphoenolpyruvate (PEP):maltose phosphotransferase system (PTS). The maltose-specific PTS permease is encoded by the malT gene. However, E. faecalis lacks a malA gene encoding a 6-phospho-a-glucosidase, which in B. subtilis hydrolyses maltose 6-P into glucose and glucose 6-P. Instead, an operon encoding a maltose phosphorylase (MalP), a phosphoglucomutase and a mutarotase starts upstream from malT. MalP was suggested to split maltose 6-P into glucose 1-P and glucose 6-P. However, purified MalP phosphorolyses maltose but not maltose 6-P. We discovered that the gene downstream from malT encodes a novel enzyme (MapP) that dephosphorylates maltose 6-P formed by the PTS. The resulting intracellular maltose is cleaved by MalP into glucose and glucose 1-P. Slow uptake of maltose probably via a maltodextrin ABC transporter allows poor growth for the mapP but not the malP mutant. Synthesis of MapP in a B. subtilis mutant accumulating maltose 6-P restored growth on maltose. MapP catalyses the dephosphorylation of intracellular maltose 6-P, and the resulting maltose is converted by the B. subtilis maltose phosphorylase into glucose and glucose 1-P. MapP therefore connects PTS-mediated maltose uptake to maltose phosphorylase-catalysed metabolism. Dephosphorylation assays with a wide variety of phosphosubstrates revealed that MapP preferably dephosphorylates disaccharides containing an O-aglycosyl linkageFil: Mokhtari, Abdelhamid. Institut National de la Recherche Agronomique. Microbiologie de l’Alimentation au Service de la Santé Humaine; Francia. University Mentouri. Faculty of Natural Science and Life. Department of Biochemistry-Microbiology. Laboratory of Environmental Biology; ArgeliaFil: Blancato, Victor Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Repizo, Guillermo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Henry, Céline. Institut National de la Recherche Agronomique. Microbiologie de l’Alimentation au Service de la Santé Humaine; FranciaFil: Pikis, Andreas. Center for Drug Evaluation and Research. Food and Drug Administration; Estados UnidosFil: Bourand, Alexa. Institut National de la Recherche Agronomique. Microbiologie de l’Alimentation au Service de la Santé Humaine; FranciaFil: Alvarez, Maria de Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Immel, Stefan. Technische Universität Darmstad. Institut für Organische Chemie; AlemaniaFil: Mechakra Maza, Aicha. University Mentouri. Faculty of Natural Science and Life. Department of Biochemistry-Microbiology. Laboratory of Environmental Biology; ArgeliaFil: Hartke, Axel. Universite de Caen Basse Normandie; FranciaFil: Thompson, John. National Institutes of Health. Laboratory of Cell and Developmental Biology. Microbial Biochemistry and Genetics Section; Estados UnidosFil: Magni, Christian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Deutscher, Josef. Institut National de la Recherche Agronomique. Microbiologie de l’Alimentation au Service de la Santé Humaine; Franci

    Putting surveillance data into context: The role of health care utilization surveys in understanding population burden of pneumonia in developing countries

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    AbstractBackgroundSurveillance is essential to estimating the global burden of pneumonia, yet differences in surveillance methodology and health care-seeking behaviors limit inter-country comparisons.MethodsResults were compared from community surveys measuring health care-seeking for pneumonia defined as: (1) cough and difficulty breathing for ⩾2days; or, (2) provider-diagnosed pneumonia. Surveys were conducted in six sites in Guatemala, Kenya and Thailand; these sites also conduct, active, hospital- and population-based disease surveillance for pneumonia.ResultsFrequency of self-reported pneumonia during the preceding year ranged from 1.1% (Thailand) to 6.3% (Guatemala) and was highest in children aged <5years and in urban sites. The proportion of persons with pneumonia who sought hospital-based medical services ranged from 12% (Guatemala, Kenya) to 80% (Thailand) and was highest in children <5years of age. Hospitals and private provider offices were the most common places where persons with pneumonia sought health care. The most commonly cited reasons for not seeking health care were: (a) mild illness; (b) already recovering; and (3) cost of treatment.ConclusionsHealth care-seeking patterns varied widely across countries. Using results from standardized health care utilization surveys to adjust facility-based surveillance estimates of pneumonia allows for more accurate and comparable estimates

    Characterization of cleavage events in the multifunctional cilium adhesin Mhp684 (P146) reveals a mechanism by which mycoplasma hyopneumoniae regulates surface topography

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    Mycoplasma hyopneumoniae causes enormous economic losses to swine production worldwide by colonizing the ciliated epithelium in the porcine respiratory tract, resulting in widespread damage to the mucociliary escalator, prolonged inflammation, reduced weight gain, and secondary infections. Protein Mhp684 (P146) comprises 1,317 amino acids, and while the N-terminal 400 residues display significant sequence identity to the archetype cilium adhesin P97, the remainder of the molecule is novel and displays unusual motifs. Proteome analysis shows that P146 preprotein is endogenously cleaved into three major fragments identified here as P50P146, P40P146, and P85P146 that reside on the cell surface. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) identified a semitryptic peptide that delineated a major cleavage site in Mhp684. Cleavage occurred at the phenylalanine residue within sequence 672ATEF2QQ677, consistent with a cleavage motif resembling S/T-X-F2XD/E recently identified in Mhp683 and other P97/P102 family members. Biotinylated surface proteins recovered by avidin chromatography and separated by two-dimensional gel electrophoresis (2-D GE) showed that more-extensive endoproteolytic cleavage of P146 occurs. Recombinant fragments F1P146-F3P146 that mimic P50P146, P40P146, and P85P146 were constructed and shown to bind porcine epithelial cilia and biotinylated heparin with physiologically relevant affinity. Recombinant versions of F3P146 generated from M. hyopneumoniae strain J and 232 sequences strongly bind porcine plasminogen, and the removal of their respective C-terminal lysine and arginine residues significantly reduces this interaction. These data reveal that P146 is an extensively processed, multifunctional adhesin of M. hyopneumoniae. Extensive cleavage coupled with variable cleavage efficiency provides a mechanism by which M. hyopneumoniae regulates protein topography

    Comparing patient characteristics and treatment processes in patients receiving physical therapy in the United States, Israel and the Netherlands. Cross sectional analyses of data from three clinical databases

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    <p>Abstract</p> <p>Background</p> <p>Many assume that outcomes from physical therapy research in one country can be generalized to other countries. However, no well designed studies comparing outcomes among countries have been conducted. In this exploratory study, our goal was to compare patient demographics and treatment processes in outpatient physical therapy practice in the United States, Israel and the Netherlands.</p> <p>Methods</p> <p>Cross-sectional data from three different clinical databases were examined. Data were selected for patients aged 18 years and older and started an episode of outpatient therapy between January 1<sup>st </sup>2005 and December 31<sup>st </sup>2005. Results are based on data from approximately 63,000 patients from the United States, 100,000 from Israel and 12,000 from the Netherlands.</p> <p>Results</p> <p>Age, gender and the body part treated were similar in the three countries. Differences existed in episode duration of the health problem, with more patients with chronic complaints treated in the United States and Israel compared to the Netherlands. In the United States and Israel, physical agents and mechanical modalities were applied more often than in the Netherlands. The mean number of visits per treatment episode, adjusted for age, gender, and episode duration, varied from 8 in Israel to 11 in the United States and the Netherlands.</p> <p>Conclusion</p> <p>The current study showed that clinical databases can be used for comparing patient demographic characteristics and for identifying similarities and differences among countries in physical therapy practice. However, terminology used to describe treatment processes and classify patients was different among databases. More standardisation is required to enable more detailed comparisons. Nevertheless the differences found in number of treatment visits per episode imply that one has to be careful to generalize outcomes from physical therapy research from one country to another.</p

    Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data

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    We use 2009-2011 space-borne methane observations from the Greenhouse Gases Observing SATellite (GOSAT) to estimate global and North American methane emissions with 4° x 5° and up to 50 km x 50 km spatial resolution, respectively. GEOS-Chem and GOSAT data are first evaluated with atmospheric methane observations from surface and tower networks (NOAA/ESRL, TCCON) and aircraft (NOAA/ESRL, HIPPO), using the GEOS-Chem chemical transport model as a platform to facilitate comparison of GOSAT with in situ data. This identifies a high-latitude bias between the GOSAT data and GEOS-Chem that we correct via quadratic regression. Our global adjoint-based inversion yields a total methane source of 539 Tg a−1 with some important regional corrections to the EDGARv4.2 inventory used as a prior. Results serve as dynamic boundary conditions for an analytical inversion of North American methane emissions using radial basis functions to achieve high resolution of large sources and provide error characterization. We infer a US anthropogenic methane source of 40.2-42.7 Tg a−1, as compared to 24.9-27.0 Tg a−1 in the EDGAR and EPA bottom-up inventories, and 30.0-44.5 Tg a−1 in recent inverse studies. Our estimate is supported by independent surface and aircraft data and by previous inverse studies for California. We find that the emissions are highest in the southern-central US, the Central Valley of California, and Florida wetlands; large isolated point sources such as the US Four Corners also contribute. Using prior information on source locations, we attribute 29-44 % of US anthropogenic methane emissions to livestock, 22-31 % to oil/gas, 20 % to landfills/wastewater, and 11-15 % to coal. Wetlands contribute an additional 9.0-10.1 Tg a−1

    Respiration driven CO2 pulses dominate Australia's flux variability

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    The Australian continent contributes substantially to the year-to-year variability of the global terrestrial carbon dioxide (CO2) sink. However, the scarcity of in-situ observations in remote areas prevents deciphering the processes that force the CO2 flux variability. Here, examining atmospheric CO2 measurements from satellites in the period 2009-2018, we find recurrent end-of-dry-season CO2 pulses over the Australian continent. These pulses largely control the year-to-year variability of Australia's CO2 balance, due to 2-3 times higher seasonal variations compared to previous top-down inversions and bottom-up estimates. The CO2 pulses occur shortly after the onset of rainfall and are driven by enhanced soil respiration preceding photosynthetic uptake in Australia's semi-arid regions. The suggested continental-scale relevance of soil rewetting processes has large implications for our understanding and modelling of global climate-carbon cycle feedbacks.Comment: 28 pages (including supplementary materials), 3 main figures, 7 supplementary figure

    Culture and collective action: Japan, Germany and the United States after 11 September 2001

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    In order to put a lens on the issue of international security cooperation after 11 September 2001, this article examines the question of how collective action in International Relations becomes possible. The author maintains that a fair amount of inter-state collective action can be understood, even explained, by analysing the culture of the international system. Using discourse analysis as a tool, the analysis addresses the underlying ideas, norms and identities that constitute the relationship between the United States and Japan, on the one hand, and Germany and the United States, on the other, as it has evolved since September 2001. The method exposes how some ideas are privileged over others, how norms are maintained, reformulated and abandoned, how identity is constructed and how power is legitimized in the 'war on terror'

    Who Is at Risk for Diagnostic Discrepancies? Comparison of Pre- and Postmortal Diagnoses in 1800 Patients of 3 Medical Decades in East and West Berlin

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    <div><h3>Background</h3><p>Autopsy rates in Western countries consistently decline to an average of <5%, although clinical autopsies represent a reasonable tool for quality control in hospitals, medically and economically. Comparing pre- and postmortal diagnoses, diagnostic discrepancies as uncovered by clinical autopsies supply crucial information on how to improve clinical treatment. The study aimed at analyzing current diagnostic discrepancy rates, investigating their influencing factors and identifying risk profiles of patients that could be affected by a diagnostic discrepancy.</p> <h3>Methods and Findings</h3><p>Of all adult autopsy cases of the Charité Institute of Pathology from the years 1988, 1993, 1998, 2003 and 2008, the pre- and postmortal diagnoses and all demographic data were analyzed retrospectively. Based on power analysis, 1,800 cases were randomly selected to perform discrepancy classification (class I-VI) according to modified Goldman criteria. The rate of discrepancies in major diagnoses (class I) was 10.7% (95% CI: 7.7%–14.7%) in 2008 representing a reduction by 15.1%. Subgroup analysis revealed several influencing factors to significantly correlate with the discrepancy rate. Cardiovascular diseases had the highest frequency among class-I-discrepancies. Comparing the 1988-data of East- and West-Berlin, no significant differences were found in diagnostic discrepancies despite an autopsy rate differing by nearly 50%. A risk profile analysis visualized by intuitive heatmaps revealed a significantly high discrepancy rate in patients treated in low or intermediate care units at community hospitals. In this collective, patients with genitourinary/renal or infectious diseases were at particularly high risk.</p> <h3>Conclusions</h3><p>This is the current largest and most comprehensive study on diagnostic discrepancies worldwide. Our well-powered analysis revealed a significant rate of class-I-discrepancies indicating that autopsies are still of value. The identified risk profiles may aid both pathologists and clinicians to identify patients at increased risk for a discrepant diagnosis and possibly suboptimal treatment intra vitam.</p> </div
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