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51.
Kate M. Scott Karestan C. Koenen Sergio Aguilar-Gaxiola Jordi Alonso Matthias C. Angermeyer Corina Benjet Ronny Bruffaerts Jose Miguel Caldas-de-Almeida Giovanni de Girolamo Silvia Florescu Noboru Iwata Daphna Levinson Carmen C. W. Lim Sam Murphy Johan Ormel Jose Posada-Villa Ronald C. Kessler 《PloS one》2013,8(11)
Background
Associations between lifetime traumatic event (LTE) exposures and subsequent physical ill-health are well established but it has remained unclear whether these are explained by PTSD or other mental disorders. This study examined this question and investigated whether associations varied by type and number of LTEs, across physical condition outcomes, or across countries.Methods
Cross-sectional, face-to-face household surveys of adults (18+) were conducted in 14 countries (n = 38, 051). The Composite International Diagnostic Interview assessed lifetime LTEs and DSM-IV mental disorders. Chronic physical conditions were ascertained by self-report of physician''s diagnosis and year of diagnosis or onset. Survival analyses estimated associations between the number and type of LTEs with the subsequent onset of 11 physical conditions, with and without adjustment for mental disorders.Findings
A dose-response association was found between increasing number of LTEs and odds of any physical condition onset (OR 1.5 [95% CI: 1.4–1.5] for 1 LTE; 2.1 [2.0–2.3] for 5+ LTEs), independent of all mental disorders. Associations did not vary greatly by type of LTE (except for combat and other war experience), nor across countries. A history of 1 LTE was associated with 7/11 of the physical conditions (ORs 1.3 [1.2–1.5] to 1.7 [1.4–2.0]) and a history of 5+ LTEs was associated with 9/11 physical conditions (ORs 1.8 [1.3–2.4] to 3.6 [2.0–6.5]), the exceptions being cancer and stroke.Conclusions
Traumatic events are associated with adverse downstream effects on physical health, independent of PTSD and other mental disorders. Although the associations are modest they have public health implications due to the high prevalence of traumatic events and the range of common physical conditions affected. The effects of traumatic stress are a concern for all medical professionals and researchers, not just mental health specialists. 相似文献52.
Kate Rowntree 《African Journal of Aquatic Science》2013,38(1-2):28-43
Summary Invasion of the riparian zone by alien vegetation is recognised as a serious problem in many areas of South Africa. Vegetation is a dynamic component of river channels. It is an important control variable affecting channel form whereas the flow and sediment regime influences vegetation growth. Wherever alien vegetation invades the riparian zone it can be expected that there will be some impact on the physical structure of the riparian habitat. This paper reviews the effect of riparian vegetation on channel processes and channel form and discusses the implications of the invasion of riparian zones by alien vegetation. Woody species in particular are seen as having a significant potential for inducing channel modification, whilst their removal could lead to significant channel instability and mobilisation of sediment. The need for further research into the impact of alien vegetation on the geomorphology of South African river channels is stressed. 相似文献
53.
Plant integrity looks like a “very easy and expanded topic,” but the reality is totally different. Thanks to the very high specialization of scientists, we are losing a holistic view of plants and are making mistakes in our research due to this drawback. It is necessary to sense a plant in their whole complexity—in both roots and shoot, as well as throughout their life cycles. Only such an integrated approach can allow us to reach correct interpretations of our experimental results. 相似文献
54.
The relationship between inherent internal conformational processes and enzymatic activity or thermodynamic stability of proteins has proven difficult to characterize. The study of homologous proteins with differing thermostabilities offers an especially useful approach for understanding the functional aspects of conformational dynamics. In particular, ribonuclease HI (RNase H), an 18 kD globular protein that hydrolyzes the RNA strand of RNA:DNA hybrid substrates, has been extensively studied by NMR spectroscopy to characterize the differences in dynamics between homologs from the mesophilic organism E. coli and the thermophilic organism T. thermophilus. Herein, molecular dynamics simulations are reported for five homologous RNase H proteins of varying thermostabilities and enzymatic activities from organisms of markedly different preferred growth temperatures. For the E. coli and T. thermophilus proteins, strong agreement is obtained between simulated and experimental values for NMR order parameters and for dynamically averaged chemical shifts, suggesting that these simulations can be a productive platform for predicting the effects of individual amino acid residues on dynamic behavior. Analyses of the simulations reveal that a single residue differentiates between two different and otherwise conserved dynamic processes in a region of the protein known to form part of the substrate-binding interface. Additional key residues within these two categories are identified through the temperature-dependence of these conformational processes. 相似文献
55.
Kate Kosmac Glenn R. Bantug Ester P. Pugel Djurdjica Cekinovic Stipan Jonjic William J. Britt 《PLoS pathogens》2013,9(3)
Infection of the developing fetus with human cytomegalovirus (HCMV) is a major cause of central nervous system disease in infants and children; however, mechanism(s) of disease associated with this intrauterine infection remain poorly understood. Utilizing a mouse model of HCMV infection of the developing CNS, we have shown that peripheral inoculation of newborn mice with murine CMV (MCMV) results in CNS infection and developmental abnormalities that recapitulate key features of the human infection. In this model, animals exhibit decreased granule neuron precursor cell (GNPC) proliferation and altered morphogenesis of the cerebellar cortex. Deficits in cerebellar cortical development are symmetric and global even though infection of the CNS results in a non-necrotizing encephalitis characterized by widely scattered foci of virus-infected cells with mononuclear cell infiltrates. These findings suggested that inflammation induced by MCMV infection could underlie deficits in CNS development. We investigated the contribution of host inflammatory responses to abnormal cerebellar development by modulating inflammatory responses in infected mice with glucocorticoids. Treatment of infected animals with glucocorticoids decreased activation of CNS mononuclear cells and expression of inflammatory cytokines (TNF-α, IFN-β and IFNγ) in the CNS while minimally impacting CNS virus replication. Glucocorticoid treatment also limited morphogenic abnormalities and normalized the expression of developmentally regulated genes within the cerebellum. Importantly, GNPC proliferation deficits were normalized in MCMV infected mice following glucocorticoid treatment. Our findings argue that host inflammatory responses to MCMV infection contribute to deficits in CNS development in MCMV infected mice and suggest that similar mechanisms of disease could be responsible for the abnormal CNS development in human infants infected in-utero with HCMV. 相似文献
56.
Kerry A. Miller Casey J. Ah-Cann Megan F. Welfare Tiong Y. Tan Kate Pope Georgina Caruana Mary-Louise Freckmann Ravi Savarirayan John F. Bertram Michael S. Dobbie John F. Bateman Peter G. Farlie 《PLoS genetics》2013,9(8)
Cilia are architecturally complex organelles that protrude from the cell membrane and have signalling, sensory and motility functions that are central to normal tissue development and homeostasis. There are two broad categories of cilia; motile and non-motile, or primary, cilia. The central role of primary cilia in health and disease has become prominent in the past decade with the recognition of a number of human syndromes that result from defects in the formation or function of primary cilia. This rapidly growing class of conditions, now known as ciliopathies, impact the development of a diverse range of tissues including the neural axis, craniofacial structures, skeleton, kidneys, eyes and lungs. The broad impact of cilia dysfunction on development reflects the pivotal position of the primary cilia within a signalling nexus involving a growing number of growth factor systems including Hedgehog, Pdgf, Fgf, Hippo, Notch and both canonical Wnt and planar cell polarity. We have identified a novel ENU mutant allele of Ift140, which causes a mid-gestation embryonic lethal phenotype in homozygous mutant mice. Mutant embryos exhibit a range of phenotypes including exencephaly and spina bifida, craniofacial dysmorphism, digit anomalies, cardiac anomalies and somite patterning defects. A number of these phenotypes can be attributed to alterations in Hedgehog signalling, although additional signalling systems are also likely to be involved. We also report the identification of a homozygous recessive mutation in IFT140 in a Jeune syndrome patient. This ENU-induced Jeune syndrome model will be useful in delineating the origins of dysmorphology in human ciliopathies. 相似文献
57.
Nikola Ková?ová Tomá? Mrá?ek Hana N?sková Eli?ka Holzerová Marek Vrbacky Petr Pecina Kate?ina Hejzlarová Katarína K?u?ková Jakub Rohlena Jiri Neuzil Josef Hou?těk 《PloS one》2013,8(8)
Mitochondrial respiratory chain is organised into supramolecular structures that can be preserved in mild detergent solubilisates and resolved by native electrophoretic systems. Supercomplexes of respiratory complexes I, III and IV as well as multimeric forms of ATP synthase are well established. However, the involvement of complex II, linking respiratory chain with tricarboxylic acid cycle, in mitochondrial supercomplexes is questionable. Here we show that digitonin-solubilised complex II quantitatively forms high molecular weight structures (CIIhmw) that can be resolved by clear native electrophoresis. CIIhmw structures are enzymatically active and differ in electrophoretic mobility between tissues (500 – over 1000 kDa) and cultured cells (400–670 kDa). While their formation is unaffected by isolated defects in other respiratory chain complexes, they are destabilised in mtDNA-depleted, rho0 cells. Molecular interactions responsible for the assembly of CIIhmw are rather weak with the complexes being more stable in tissues than in cultured cells. While electrophoretic studies and immunoprecipitation experiments of CIIhmw do not indicate specific interactions with the respiratory chain complexes I, III or IV or enzymes of the tricarboxylic acid cycle, they point out to a specific interaction between CII and ATP synthase. 相似文献
58.
Martine Stead Crawford Moodie Kathryn Angus Linda Bauld Ann McNeill James Thomas Gerard Hastings Kate Hinds Alison O'Mara-Eves Irene Kwan Richard I. Purves Stuart L. Bryce 《PloS one》2013,8(10)
Background and Objectives
Standardised or ‘plain’ tobacco packaging was introduced in Australia in December 2012 and is currently being considered in other countries. The primary objective of this systematic review was to locate, assess and synthesise published and grey literature relating to the potential impacts of standardised tobacco packaging as proposed by the guidelines for the international Framework Convention on Tobacco Control: reduced appeal, increased salience and effectiveness of health warnings, and more accurate perceptions of product strength and harm.Methods
Electronic databases were searched and researchers in the field were contacted to identify studies. Eligible studies were published or unpublished primary research of any design, issued since 1980 and concerning tobacco packaging. Twenty-five quantitative studies reported relevant outcomes and met the inclusion criteria. A narrative synthesis was conducted.Results
Studies that explored the impact of package design on appeal consistently found that standardised packaging reduced the appeal of cigarettes and smoking, and was associated with perceived lower quality, poorer taste and less desirable smoker identities. Although findings were mixed, standardised packs tended to increase the salience and effectiveness of health warnings in terms of recall, attention, believability and seriousness, with effects being mediated by the warning size, type and position on pack. Pack colour was found to influence perceptions of product harm and strength, with darker coloured standardised packs generally perceived as containing stronger tasting and more harmful cigarettes than fully branded packs; lighter coloured standardised packs suggested weaker and less harmful cigarettes. Findings were largely consistent, irrespective of location and sample.Conclusions
The evidence strongly suggests that standardised packaging will reduce the appeal of packaging and of smoking in general; that it will go some way to reduce consumer misperceptions regarding product harm based upon package design; and will help make the legally required on-pack health warnings more salient. 相似文献59.
A Modified RNA-Seq Approach for Whole Genome Sequencing of RNA Viruses from Faecal and Blood Samples
Elizabeth M. Batty T. H. Nicholas Wong Amy Trebes Karène Argoud Moustafa Attar David Buck Camilla L. C. Ip Tanya Golubchik Madeleine Cule Rory Bowden Charis Manganis Paul Klenerman Eleanor Barnes A. Sarah Walker David H. Wyllie Daniel J. Wilson Kate E. Dingle Tim E. A. Peto Derrick W. Crook Paolo Piazza 《PloS one》2013,8(6)
To date, very large scale sequencing of many clinically important RNA viruses has been complicated by their high population molecular variation, which creates challenges for polymerase chain reaction and sequencing primer design. Many RNA viruses are also difficult or currently not possible to culture, severely limiting the amount and purity of available starting material. Here, we describe a simple, novel, high-throughput approach to Norovirus and Hepatitis C virus whole genome sequence determination based on RNA shotgun sequencing (also known as RNA-Seq). We demonstrate the effectiveness of this method by sequencing three Norovirus samples from faeces and two Hepatitis C virus samples from blood, on an Illumina MiSeq benchtop sequencer. More than 97% of reference genomes were recovered. Compared with Sanger sequencing, our method had no nucleotide differences in 14,019 nucleotides (nt) for Noroviruses (from a total of 2 Norovirus genomes obtained with Sanger sequencing), and 8 variants in 9,542 nt for Hepatitis C virus (1 variant per 1,193 nt). The three Norovirus samples had 2, 3, and 2 distinct positions called as heterozygous, while the two Hepatitis C virus samples had 117 and 131 positions called as heterozygous. To confirm that our sample and library preparation could be scaled to true high-throughput, we prepared and sequenced an additional 77 Norovirus samples in a single batch on an Illumina HiSeq 2000 sequencer, recovering >90% of the reference genome in all but one sample. No discrepancies were observed across 118,757 nt compared between Sanger and our custom RNA-Seq method in 16 samples. By generating viral genomic sequences that are not biased by primer-specific amplification or enrichment, this method offers the prospect of large-scale, affordable studies of RNA viruses which could be adapted to routine diagnostic laboratory workflows in the near future, with the potential to directly characterize within-host viral diversity. 相似文献
60.
Kate Bramham Carlos E. Poli-de-Figueiredo Paul T. Seed Annette L. Briley Lucilla Poston Andrew H. Shennan Lucy C. Chappell 《PloS one》2013,8(10)