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991.
Daniel Tiller Martin Russ Karin Halina Greiser Sebastian Nuding Henning Ebelt Alexander Kluttig Jan A. Kors Joachim Thiery Mathias Bruegel Johannes Haerting Karl Werdan 《PloS one》2013,8(3)
Background/Objectives
Chronic heart failure (CHF) is one of the most important public health concerns in the industrialized world having increasing incidence and prevalence. Although there are several studies describing the prevalence of heart failure with reduced ejection fraction (HFREF) and heart failure with normal ejection fraction (HFNEF) in selected populations, there are few data regarding the prevalence and the determinants of symptomatic heart failure in the general population.Methods
Cross-sectional data of a population-based German sample (1,779 subjects aged 45–83 years) were analyzed to determine the prevalence and determinants of chronic SHF and HFNEF defined according to the European Society of Cardiology using symptoms, echocardiography and serum NT-proBNP. Prevalence was age-standardized to the German population as of December 31st, 2005.Results
The overall age-standardized prevalence of symptomatic CHF was 7.7% (95%CI 6.0–9.8) for men and 9.0% (95%CI 7.0–11.5) for women. The prevalence of CHF strongly increased with age from 3.0% among 45–54- year-old subjects to 22.0% among 75–83- year-old subjects. Symptomatic HFREF could be shown in 48% (n = 78), symptomatic HFNEF in 52% (n = 85) of subjects with CHF. The age-standardized prevalence of HFREF was 3.8 % (95%CI 2.4–5.8) for women and 4.6 % (95%CI 3.6–6.3) for men. The age-standardized prevalence of HFNEF for women and men was 5.1 % (95%CI 3.8–7.0) and 3.0 % (95%CI 2.1–4.5), respectively. Persons with CHF were more likely to have hypertension (PR = 3.4; 95%CI 1.6–7.3) or to have had a previous myocardial infarction (PR = 2.5, 95%CI 1.8–3.5).Conclusion
The prevalence of symptomatic CHF appears high in this population compared with other studies. While more women were affected by HFNEF than men, more male subjects suffered from HFREF. The high prevalence of symptomatic CHF seems likely to be mainly due to the high prevalence of cardiovascular risk factors in this population. 相似文献992.
Infection Frequency of Hepatitis C Virus and IL28B Haplotypes in Papua New Guinea,Fiji, and Kiribati
G. L. Abby Harrison Jan Pryor Joji Malani Mathias Supuri Andrew Masta Burentau Teriboriki Tebuka Toatu David Penny Jean-Pierre Allain Eleanor Barnes Oliver G. Pybus Paul Klenerman 《PloS one》2013,8(8)
It has been estimated that there are more than 60 million Hepatitis C virus (HCV) carriers in the World Health Organisation''s Western Pacific region (WHO-WPR), where liver cancer is among the top three causes of cancer death. WHO and the US Centres for Disease Control and Prevention report the prevalence of HCV in the South Pacific islands (countries within the WHO-WPR) to be high (5–10% and >2% respectively). However, since HCV is not tested for in many of these countries, there is sparse data available to support this assertion. We screened ∼2000 apparently healthy individuals from Papua New Guinea, Fiji and Kiribati and found a sero-prevalence of 2.0%, 0.1% and 0%, respectively. All sero-positive samples tested negative for HCV RNA. Curious as to why all the sero-positive individuals were negative for HCV-RNA, we also screened them for the HCV protective IL28B SNP markers rs12979860 and rs8099917. All antibody-positive participants bar one had HCV protective haplotypes. Our results suggest that HCV is present in these Pacific island countries, albeit at a prevalence lower than previous estimates. As none of our participants had undergone antiviral treatment, and therefore must have cleared infection naturally, we hypothesise that genotypes 1 and/or 4 are circulating in South Pacific Island people and that these peoples are genetically predisposed to be more likely to spontaneous resolve HCV infection than to become chronic carriers. 相似文献
993.
Tetyana Zakharkina Elke Heinzel Rembert A. Koczulla Timm Greulich Katharina Rentz Josch K. Pauling Jan Baumbach Mathias Herrmann Christiane Grünewald Hendrik Dienemann Lutz von Müller Robert Bals 《PloS one》2013,8(7)
Chronic obstructive pulmonary disease (COPD) is a progressive, inflammatory lung disease that affects a large number of patients and has significant impact. One hallmark of the disease is the presence of bacteria in the lower airways. Objective: The aim of this study was to analyze the detailed structure of microbial communities found in the lungs of healthy individuals and patients with COPD. Nine COPD patients as compared and 9 healthy individuals underwent flexible bronchoscopy and BAL was performed. Bacterial nucleic acids were subjected to terminal restriction fragment (TRF) length polymorphism and clone library analysis. Overall, we identified 326 T-RFLP band, 159 in patients and 167 in healthy controls. The results of the TRF analysis correlated partly with the data obtained from clone sequencing. Although the results of the sequencing showed high diversity, the genera Prevotella, Sphingomonas, Pseudomonas, Acinetobacter, Fusobacterium, Megasphaera, Veillonella, Staphylococcus, and Streptococcus constituted the major part of the core microbiome found in both groups. A TRF band possibly representing Pseudomonas sp. monoinfection was associated with a reduction of the microbial diversity. Non-cultural methods reveal the complexity of the pulmonary microbiome in healthy individuals and in patients with COPD. Alterations of the microbiome in pulmonary diseases are correlated with disease. 相似文献
994.
Stephanie H. Capone Murielle Dufresne Mathias Rechel Marie-José Fleury Anne-Virginie Salsac Patrick Paullier Martine Daujat-Chavanieu Cecile Legallais 《PloS one》2013,8(4)
Recently, interest has focused on hepatocytes’ implantation to provide end stage liver failure patients with a temporary support until spontaneous recovery or a suitable donor becomes available. To avoid cell damage and use of an immunosuppressive treatment, hepatic cells could be implanted after encapsulation in a porous biomaterial of bead or capsule shape. The aim of this study was to compare the production and the physical properties of the beads, together with some hepatic cell functions, resulting from the use of different material combinations for cell microencapsulation: alginate alone or combined with type I collagen with or without poly-L-lysine and alginate coatings. Collagen and poly-L-lysine increased the bead mechanical resistance but lowered the mass transfer kinetics of vitamin B12. Proliferation of encapsulated HepG2/C3A cells was shown to be improved in alginate-collagen beads. Finally, when the beads were subcutaneously implanted in mice, the inflammatory response was reduced in the case of alginate mixed with collagen. This in vitro and in vivo study clearly outlines, based on a systematic comparison, the necessity of compromising between material physical properties (mechanical stability and porosity) and cell behavior (viability, proliferation, functionalities) to define optima hepatic cell microencapsulation conditions before implantation. 相似文献
995.
996.
Onno M. Mets Pim A. de Jong Bram van Ginneken Cas L. J. J. Kruitwagen Mathias Prokop Matthijs Oudkerk Jan-Willem J. Lammers Pieter Zanen 《PloS one》2013,8(4)
Purpose
We aimed to study the association between lung function decline and quantitative computed tomography (CT) air trapping.Materials and Methods
Current and former heavy smokers in a lung cancer screening trial underwent volumetric low-dose CT in inspiration and expiration. Spirometry was obtained at baseline and after 3 years. The expiratory to inspiratory ratio of mean lung density (E/I-ratioMLD) was used to quantify air trapping. CT emphysema was defined as voxels in inspiratory CT below −950 Hounsfield Unit. Linear mixed modeling was used to determine the association between CT air trapping and lung function.Results
We included 985 subjects with a mean age of 61.3 years. Independent of CT emphysema, CT air trapping was significantly associated with a reduction in forced expiratory volume in one second (FEV1) and the ratio of FEV1 over the forced vital capacity (FEV1/FVC); FEV1 declines with 33 mL per percent increase in CT air trapping, while FEV1/FVC declines 0.58% per percent increase (both p<0.001). CT air trapping further elicits accelerated loss of FEV1/FVC (additional 0.24% reduction per percent increase; p = 0.014).Conclusion
In a lung cancer screening cohort, quantitatively assessed air trapping on low-dose CT is independently associated with reduced lung function and accelerated decline of FEV1/FVC. 相似文献997.
Eva C. Arnspang Jeremy Schwartzentruber Mathias P. Clausen Paul W. Wiseman B. Christoffer Lagerholm 《PloS one》2013,8(12)
The lateral dynamics of proteins and lipids in the mammalian plasma membrane are heterogeneous likely reflecting both a complex molecular organization and interactions with other macromolecules that reside outside the plane of the membrane. Several methods are commonly used for characterizing the lateral dynamics of lipids and proteins. These experimental and data analysis methods differ in equipment requirements, labeling complexities, and further oftentimes give different results. It would therefore be very convenient to have a single method that is flexible in the choice of fluorescent label and labeling densities from single molecules to ensemble measurements, that can be performed on a conventional wide-field microscope, and that is suitable for fast and accurate analysis. In this work we show that k-space image correlation spectroscopy (kICS) analysis, a technique which was originally developed for analyzing lateral dynamics in samples that are labeled at high densities, can also be used for fast and accurate analysis of single molecule density data of lipids and proteins labeled with quantum dots (QDs). We have further used kICS to investigate the effect of the label size and by comparing the results for a biotinylated lipid labeled at high densities with Atto647N-strepatvidin (sAv) or sparse densities with sAv-QDs. In this latter case, we see that the recovered diffusion rate is two-fold greater for the same lipid and in the same cell-type when labeled with Atto647N-sAv as compared to sAv-QDs. This data demonstrates that kICS can be used for analysis of single molecule data and furthermore can bridge between samples with a labeling densities ranging from single molecule to ensemble level measurements. 相似文献
998.
Victoria K. Baxter Gillian C. Shaw Nathaniel P. Sotuyo Cathy S. Carlson Erik J. Olson M. Christine Zink Joseph L. Mankowski Robert J. Adams Eric K. Hutchinson Kelly A. Metcalf Pate 《PloS one》2013,8(12)
The increasing use of the common marmoset (Callithrix jacchus) in research makes it important to diagnose spontaneous disease that may confound experimental studies. Bone disease and gastrointestinal disease are two major causes of morbidity and mortality in captive marmosets, but currently no effective antemortem tests are available to identify affected animals prior to the terminal stage of disease. In this study we propose that bone disease and gastrointestinal disease are associated disease entities in marmosets and aim to establish the efficacy of several economical antemortem tests in identifying and predicting disease. Tissues from marmosets were examined to define affected animals and unaffected controls. Complete blood count, serum chemistry values, body weight, quantitative radiographs, and tissue-specific biochemical markers were evaluated as candidate biomarkers for disease. Bone and gastrointestinal disease were associated, with marmosets being over seven times more likely to have either concurrent bone and gastrointestinal disease or neither disease as opposed to lesions in only one organ system. When used in tandem, serum albumin <3.5 g/dL and body weight <325 g identified 100% of the marmosets affected with concurrent bone and gastrointestinal disease. Progressive body weight loss of 0.05% of peak body weight per day predicted which marmosets would develop disease prior to the terminal stage. Bone tissue-specific tests, such as quantitative analysis of radiographs and serum parathyroid hormone levels, were effective for distinguishing between marmosets with bone disease and those without. These results provide an avenue for making informed decisions regarding the removal of affected marmosets from studies in a timely manner, preserving the integrity of research results. 相似文献
999.
Ernst Th. Scholten Bartjan de Hoop Colin Jacobs Saskia van Amelsvoort-van de Vorst Rob J. van Klaveren Matthijs Oudkerk Rozemarijn Vliegenthart Harry J. de Koning Carlijn M. van der Aalst Willem Th M. Mali Hester A. Gietema Mathias Prokop Bram van Ginneken Pim A. de Jong 《PloS one》2013,8(11)
Rationale
Accurate measurement of subsolid pulmonary nodules (SSN) is becoming increasingly important in the management of these nodules. SSNs were previously quantified with time-consuming manual measurements. The aim of the present study is to test the feasibility of semi-automatic SSNs measurements and to compare the results to the manual measurements.Methods
In 33 lung cancer screening participants with 33 SSNs, the nodules were previously quantified by two observers manually. In the present study two observers quantified these nodules by using semi-automated nodule volumetry software. Nodules were quantified for effective diameter, volume and mass. The manual and semi-automatic measurements were compared using Bland-Altman plots and paired T tests. Observer agreement was calculated as an intraclass correlation coefficient. Data are presented as mean (SD).Results
Semi-automated measurements were feasible in all 33 nodules. Nodule diameter, volume and mass were 11.2 (3.3) mm, 935 (691) ml and 379 (311) milligrams for observer 1 and 11.1 (3.7) mm, 986 (797) ml and 399 (344) milligrams for observer 2, respectively. Agreement between observers and within observer 1 for the semi-automatic measurements was good with an intraclass correlation coefficient >0.89. For observer 1 and observer 2, measured diameter was 8.8% and 10.3% larger (p<0.001), measured volume was 24.3% and 26.5% larger (p<0.001) and measured mass was 10.6% and 12.0% larger (p<0.001) with the semi-automatic program compared to the manual measurements.Conclusion
Semi-automated measurement of the diameter, volume and mass of SSNs is feasible with good observer agreement. Semi-automated measurement makes quantification of mass and volume feasible in daily practice. 相似文献1000.
Valentina Coia Marco Capocasa Paolo Anagnostou Vincenzo Pascali Francesca Scarnicci Ilaria Boschi Cinzia Battaggia Federica Crivellaro Gianmarco Ferri Milena Alù Francesca Brisighelli George B. J. Busby Cristian Capelli Frank Maixner Giovanna Cipollini Pier Paolo Viazzo Albert Zink Giovanni Destro Bisol 《PloS one》2013,8(12)
Great European mountain ranges have acted as barriers to gene flow for resident populations since prehistory and have offered a place for the settlement of small, and sometimes culturally diverse, communities. Therefore, the human groups that have settled in these areas are worth exploring as an important potential source of diversity in the genetic structure of European populations. In this study, we present new high resolution data concerning Y chromosomal variation in three distinct Alpine ethno-linguistic groups, Italian, Ladin and German. Combining unpublished and literature data on Y chromosome and mitochondrial variation, we were able to detect different genetic patterns. In fact, within and among population diversity values observed vary across linguistic groups, with German and Italian speakers at the two extremes, and seem to reflect their different demographic histories. Using simulations we inferred that the joint effect of continued genetic isolation and reduced founding group size may explain the apportionment of genetic diversity observed in all groups. Extending the analysis to other continental populations, we observed that the genetic differentiation of Ladins and German speakers from Europeans is comparable or even greater to that observed for well known outliers like Sardinian and Basques. Finally, we found that in south Tyroleans, the social practice of Geschlossener Hof, a hereditary norm which might have favored male dispersal, coincides with a significant intra-group diversity for mtDNA but not for Y chromosome, a genetic pattern which is opposite to those expected among patrilocal populations. Together with previous evidence regarding the possible effects of “local ethnicity” on the genetic structure of German speakers that have settled in the eastern Italian Alps, this finding suggests that taking socio-cultural factors into account together with geographical variables and linguistic diversity may help unveil some yet to be understood aspects of the genetic structure of European populations. 相似文献