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111.
Laercio Martins De Stefano Alex Lombardi Barbosa Ferraz Ana Lúcia dos Anjos Ferreira Ana Lúcia Gut Ana Lúcia Cogni Elaine Farah Beatriz Bojikian Matsubara 《PloS one》2013,8(10)
Purpose
To investigate the predictors of intolerance to beta-blockers treatment and the 6-month mortality in hospitalized patients with acute coronary syndrome (ACS).Methods
This was a single-center, prospective, and longitudinal study including 370 consecutive ACS patients in Killip class I or II. BBs were prescribed according to international guidelines and withdrawn if intolerance occurred. The study was approved by the institutional ethics committee of our university. Statistics: the clinical parameters evaluated at admission, and the related intolerance to BBs and death at 6 months were analyzed using logistic regression (p<0.05)in PATIENTS.Results
BB intolerance was observed in 84 patients and was associated with no prior use of statins (OR: 2.16, 95%CI: 1.26–3.69, p= 0.005) and Killip class II (OR: 2.5, 95%CI: 1.30-4.75, p=0.004) in the model adjusted for age, sex, blood pressure, and renal function. There was no association with ST-segment alteration or left anterior descending coronary artery plaque. Intolerance to BB was associated with the greatest risk of death (OR: 4.5, 95%CI: 2.15–9.40, p<0.001).Conclusions
After ACS, intolerance to BBs in the first 48 h of admission was associated to non previous use of statin and Killip class II and had a high risk of death within 6 months. 相似文献112.
Jack H. Westwood Simon C. Groen Zhiyou Du Alex M. Murphy Damar Tri Anggoro Trisna Tungadi Vijitra Luang-In Mathew G. Lewsey John T. Rossiter Glen Powell Alison G. Smith John P. Carr 《PloS one》2013,8(12)
Background
Virus-induced deterrence to aphid feeding is believed to promote plant virus transmission by encouraging migration of virus-bearing insects away from infected plants. We investigated the effects of infection by an aphid-transmitted virus, cucumber mosaic virus (CMV), on the interaction of Arabidopsis thaliana, one of the natural hosts for CMV, with Myzus persicae (common names: ‘peach-potato aphid’, ‘green peach aphid’).Methodology/Principal Findings
Infection of Arabidopsis (ecotype Col-0) with CMV strain Fny (Fny-CMV) induced biosynthesis of the aphid feeding-deterrent 4-methoxy-indol-3-yl-methylglucosinolate (4MI3M). 4MI3M inhibited phloem ingestion by aphids and consequently discouraged aphid settling. The CMV 2b protein is a suppressor of antiviral RNA silencing, which has previously been implicated in altering plant-aphid interactions. Its presence in infected hosts enhances the accumulation of CMV and the other four viral proteins. Another viral gene product, the 2a protein (an RNA-dependent RNA polymerase), triggers defensive signaling, leading to increased 4MI3M accumulation. The 2b protein can inhibit ARGONAUTE1 (AGO1), a host factor that both positively-regulates 4MI3M biosynthesis and negatively-regulates accumulation of substance(s) toxic to aphids. However, the 1a replicase protein moderated 2b-mediated inhibition of AGO1, ensuring that aphids were deterred from feeding but not poisoned. The LS strain of CMV did not induce feeding deterrence in Arabidopsis ecotype Col-0.Conclusions/Significance
Inhibition of AGO1 by the 2b protein could act as a booby trap since this will trigger antibiosis against aphids. However, for Fny-CMV the interplay of three viral proteins (1a, 2a and 2b) appears to balance the need of the virus to inhibit antiviral silencing, while inducing a mild resistance (antixenosis) that is thought to promote transmission. The strain-specific effects of CMV on Arabidopsis-aphid interactions, and differences between the effects of Fny-CMV on this plant and those seen previously in tobacco (inhibition of resistance to aphids) may have important epidemiological consequences. 相似文献113.
Alex Fernando de Almeida Sâmia Maria Taulk-Tornisielo Eleonora Cano Carmona 《Annals of microbiology》2013,63(4):1225-1234
Microorganisms can produce lipases with different biochemical characteristics making necessary the screening of new lipase-producing strains for different industrial applications. In this study, 90 microbial strains were screened as potential lipase producers using a sensitive agar plate method with a suitable medium supplemented with Tween 20 and also a liquid culture supplemented with olive oil. The highest cell growth and lipase production for Candida viswanathii were observed in triolein and oleic acid when used as the only pure carbon source. Renewable low-cost triacylglycerols supported the best cell growth, and olive oil was found to be the best inducer for lipase production (19.50 g/L and 58.50 U). The selected conditions for enzyme production were found with yeast extract as nitrogen source and 1.5 % (w/v) olive oil (85.70 U) that resulted in a good cell growth yield (YX/S?=?1.234 g/g) and lipase productivity (1.204 U/h) after 72 h of shake-flask cultivation. C. viswanathii lipase presented high hydrolytic activity on esters bonds of triacylglycerols of long-chain, and this strain can be considered an important candidate for future applications in chemical industries. 相似文献
114.
T. Alex Perkins Thomas W. Scott Arnaud Le Menach David L. Smith 《PLoS computational biology》2013,9(12)
The Ross-Macdonald model has dominated theory for mosquito-borne pathogen transmission dynamics and control for over a century. The model, like many other basic population models, makes the mathematically convenient assumption that populations are well mixed; i.e., that each mosquito is equally likely to bite any vertebrate host. This assumption raises questions about the validity and utility of current theory because it is in conflict with preponderant empirical evidence that transmission is heterogeneous. Here, we propose a new dynamic framework that is realistic enough to describe biological causes of heterogeneous transmission of mosquito-borne pathogens of humans, yet tractable enough to provide a basis for developing and improving general theory. The framework is based on the ecological context of mosquito blood meals and the fine-scale movements of individual mosquitoes and human hosts that give rise to heterogeneous transmission. Using this framework, we describe pathogen dispersion in terms of individual-level analogues of two classical quantities: vectorial capacity and the basic reproductive number, . Importantly, this framework explicitly accounts for three key components of overall heterogeneity in transmission: heterogeneous exposure, poor mixing, and finite host numbers. Using these tools, we propose two ways of characterizing the spatial scales of transmission—pathogen dispersion kernels and the evenness of mixing across scales of aggregation—and demonstrate the consequences of a model''s choice of spatial scale for epidemic dynamics and for estimation of , both by a priori model formulas and by inference of the force of infection from time-series data. 相似文献
115.
116.
Carrie B. Moore John R. Wallace Daniel J. Wolfe Alex T. Frase Sarah A. Pendergrass Kenneth M. Weiss Marylyn D. Ritchie 《PLoS genetics》2013,9(12)
Analyses investigating low frequency variants have the potential for explaining additional genetic heritability of many complex human traits. However, the natural frequencies of rare variation between human populations strongly confound genetic analyses. We have applied a novel collapsing method to identify biological features with low frequency variant burden differences in thirteen populations sequenced by the 1000 Genomes Project. Our flexible collapsing tool utilizes expert biological knowledge from multiple publicly available database sources to direct feature selection. Variants were collapsed according to genetically driven features, such as evolutionary conserved regions, regulatory regions genes, and pathways. We have conducted an extensive comparison of low frequency variant burden differences (MAF<0.03) between populations from 1000 Genomes Project Phase I data. We found that on average 26.87% of gene bins, 35.47% of intergenic bins, 42.85% of pathway bins, 14.86% of ORegAnno regulatory bins, and 5.97% of evolutionary conserved regions show statistically significant differences in low frequency variant burden across populations from the 1000 Genomes Project. The proportion of bins with significant differences in low frequency burden depends on the ancestral similarity of the two populations compared and types of features tested. Even closely related populations had notable differences in low frequency burden, but fewer differences than populations from different continents. Furthermore, conserved or functionally relevant regions had fewer significant differences in low frequency burden than regions under less evolutionary constraint. This degree of low frequency variant differentiation across diverse populations and feature elements highlights the critical importance of considering population stratification in the new era of DNA sequencing and low frequency variant genomic analyses. 相似文献
117.
Mohlopheni J. Marakalala Simon Vautier Joanna Potrykus Louise A. Walker Kelly M. Shepardson Alex Hopke Hector M. Mora-Montes Ann Kerrigan Mihai G. Netea Graeme I. Murray Donna M. MacCallum Robert Wheeler Carol A. Munro Neil A. R. Gow Robert A. Cramer Alistair J. P. Brown Gordon D. Brown 《PLoS pathogens》2013,9(4)
118.
Seok-Hyung Kim Sarah A. Scott Michael J. Bennett Robert P. Carson Joshua Fessel H. Alex Brown Kevin C. Ess 《PLoS genetics》2013,9(6)
Multiple Acyl-CoA Dehydrogenase Deficiency (MADD) is a severe mitochondrial disorder featuring multi-organ dysfunction. Mutations in either the ETFA, ETFB, and ETFDH genes can cause MADD but very little is known about disease specific mechanisms due to a paucity of animal models. We report a novel zebrafish mutant dark xavier (dxavu463) that has an inactivating mutation in the etfa gene. dxavu463 recapitulates numerous pathological and biochemical features seen in patients with MADD including brain, liver, and kidney disease. Similar to children with MADD, homozygote mutant dxavu463 zebrafish have a spectrum of phenotypes ranging from moderate to severe. Interestingly, excessive maternal feeding significantly exacerbated the phenotype. Homozygous mutant dxavu463 zebrafish have swollen and hyperplastic neural progenitor cells, hepatocytes and kidney tubule cells as well as elevations in triacylglycerol, cerebroside sulfate and cholesterol levels. Their mitochondria were also greatly enlarged, lacked normal cristae, and were dysfunctional. We also found increased signaling of the mechanistic target of rapamycin complex 1 (mTORC1) with enlarged cell size and proliferation. Treatment with rapamycin partially reversed these abnormalities. Our results indicate that etfa gene function is remarkably conserved in zebrafish as compared to humans with highly similar pathological, biochemical abnormalities to those reported in children with MADD. Altered mTORC1 signaling and maternal nutritional status may play critical roles in MADD disease progression and suggest novel treatment approaches that may ameliorate disease severity. 相似文献
119.
Jotham Suez Steffen Porwollik Amir Dagan Alex Marzel Yosef Ilan Schorr Prerak T. Desai Vered Agmon Michael McClelland Galia Rahav Ohad Gal-Mor 《PloS one》2013,8(3)
Human infection with non-typhoidal Salmonella serovars (NTS) infrequently causes invasive systemic disease and bacteremia. To understand better the nature of invasive NTS (iNTS), we studied the gene content and the pathogenicity of bacteremic strains from twelve serovars (Typhimurium, Enteritidis, Choleraesuis, Dublin, Virchow, Newport, Bredeney, Heidelberg, Montevideo, Schwarzengrund, 9,12:l,v:- and Hadar). Comparative genomic hybridization using a Salmonella enterica microarray revealed a core of 3233 genes present in all of the iNTS strains, which include the Salmonella pathogenicity islands 1–5, 9, 13, 14; five fimbrial operons (bcf, csg, stb, sth, sti); three colonization factors (misL, bapA, sinH); and the invasion gene, pagN. In the iNTS variable genome, we identified 16 novel genomic islets; various NTS virulence factors; and six typhoid-associated virulence genes (tcfA, cdtB, hlyE, taiA, STY1413, STY1360), displaying a wider distribution among NTS than was previously known. Characterization of the bacteremic strains in C3H/HeN mice showed clear differences in disease manifestation. Previously unreported characterization of serovars Schwarzengrund, 9,12:l,v:-, Bredeney and Virchow in the mouse model showed low ability to elicit systemic disease, but a profound and elongated shedding of serovars Schwarzengrund and 9,12:l,v:- (as well as Enteritidis and Heidelberg) due to chronic infection of the mouse. Phenotypic comparison in macrophages and epithelial cell lines demonstrated a remarkable intra-serovar variation, but also showed that S. Typhimurium bacteremic strains tend to present lower intracellular growth than gastroenteritis isolates. Collectively, our data demonstrated a common core of virulence genes, which might be required for invasive salmonellosis, but also an impressive degree of genetic and phenotypic heterogeneity, highlighting that bacteremia is a complex phenotype, which cannot be attributed merely to an enhanced invasion or intracellular growth of a particular strain. 相似文献
120.
Sophie Githinji Samwel Kigen Dorothy Memusi Andrew Nyandigisi Agneta M. Mbithi Andrew Wamari Alex N. Muturi George Jagoe Jim Barrington Robert W. Snow Dejan Zurovac 《PloS one》2013,8(1)