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排序方式： 共有304条查询结果，搜索用时 15 毫秒
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Roshan Dsouza Darold R. Spillman Ronit Barkalifa Guillermo L. Monroy Eric J. Chaney Karen C. White Stephen A. Boppart 《Journal of biophotonics》2019,12(5)
The formation of biofilms in the endotracheal tubes (ETTs) of intubated patients on mechanical ventilation is associated with a greater risk of ventilator‐associated pneumonia and death. New technologies are needed to detect and monitor ETTs in vivo for the presence of these biofilms. Longitudinal OCT imaging was performed in mechanically ventilated subjects at 24‐hour intervals until extubation to detect the formation and temporal changes of in vivo ETT biofilms. OCT‐derived attenuation coefficient images were used to differentiate between mucus and biofilm. Extubated ETTs were examined with optical and electron microscopy, and all imaging results were correlated with standard‐of‐care clinical test reports. OCT and attenuation coefficient images from four subjects were positive for ETT biofilms and were negative for two subjects. The processed and stained extubated ETTs and clinical reports confirmed the presence/absence of biofilms in all subjects. Our findings confirm that OCT can detect and differentiate between biofilm‐positive and biofilm‐negative groups (P < 10?5). OCT image‐based features may serve as biomarkers for direct in vivo detection of ETT biofilms and help drive investigation of new management strategies to reduce the incidence of VAP. 相似文献
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Habitat management (e.g., intercropping) may alter within‐field spatial distribution patterns of herbivores, from a typical pattern as observed in a monoculture, and may influence patterns of crop injury. Field trials were conducted to study the effect of intercropping maize, Zea mays L. (Poaceae), with sunn hemp, Crotalaria juncea L. (Fabaceae) strips on within‐field spatial distribution patterns of corn planthopper, Peregrinus maidis (Ashmead) (Hemiptera: Delphacidae), and combined severity of hopperburn and Maize mosaic virus (MMV) (Rhabdoviridae: Nucleorhabdovirus) symptoms. In each field trial, spatially explicit data on P. maidis counts and ratings of severity of symptoms were obtained by sampling maize plants at weekly intervals. These data were used to examine the spatial patterns of P. maidis and severity of symptoms in maize‐intercropped and monoculture plots with Spatial Analysis for Distance IndicEs (SADIE) methodology. Spatial aggregation patterns of P. maidis in each treatment plot were not consistent among the field trials and tended to be mediated by their population densities. Interpolation of local cluster indices showed that P. maidis were more often aggregated at the field edges, irrespective of treatment. At times of MMV incidence in field trials (fall 2010 and spring 2011), the patch clusters of P. maidis and symptomatic plants were located at the field edges, but were spatially unassociated in both treatment plots. The results provided an approximation of the unpredictability of P. maidis spatial patterns at different population densities and their association with severity of symptoms in two maize‐cropping systems. However, the gap clusters of symptomatic plants were primarily located at the field interiors and were larger in intercropped than in monoculture plots. Such spatial pattern of symptomatic plants resulted in the reduced incidence of MMV in the intercropped plot compared with the monoculture plot, suggesting intercropping sunn hemp can be a useful tool in the management of MMV in maize fields. 相似文献
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Distinct nuclear gene expression profiles in cells with mtDNA depletion and homoplasmic A3243G mutation 总被引：2，自引：0，他引：2
Jahangir Tafrechi RS Svensson PJ Janssen GM Szuhai K Maassen JA Raap AK 《Mutation research》2005,578(1-2):43-52
The pathobiochemical pathways determining the wide variability in phenotypic expression of mitochondrial DNA (mtDNA) mutations are not well understood. Most pathogenic mtDNA mutations induce a general defect in mitochondrial respiration and thereby ATP synthesis. Yet phenotypic expression of the different mtDNA mutations shows large variations that are difficult to reconcile with ATP depletion as sole pathogenic factor, implying that additional mechanisms contribute to the phenotype. Here, we use DNA microarrays to identify changes in nuclear gene expression resulting from the presence of the A3243G diabetogenic mutation and from a depletion of mtDNA (rho0 cells). We find that cells respond mildly to these mitochondrial states with both general and specific changes in nuclear gene expression. This observation indicates that cells can sense the status of mtDNA. A number of genes show divergence in expression in rho0 cells compared to cells with the A3243G mutation, such as genes involved in oxidative phosphorylation. As a common response in A3243G and rho0 cells, mRNA levels for extracellular matrix genes are up-regulated, while the mRNA levels of genes involved in ubiquitin-mediated protein degradation and in ribosomal protein synthesis is down-regulated. This reduced expression is reflected at the level of cytosolic protein synthesis in both A3243G and rho0 cells. Our finding that mitochondrial dysfunction caused by different mutations affects nuclear gene expression in partially distinct ways suggests that multiple pathways link mitochondrial function to nuclear gene expression and contribute to the development of the different phenotypes in mitochondrial disease. 相似文献
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Jonah Elliff Aparna Biswas Poonam Roshan Sahiti Kuppa Angela Patterson Jenna Mattice Mathivanan Chinnaraj Ryan Burd Sarah E Walker Nicola Pozzi Edwin Antony Brian Bothner Sofia Origanti 《Nucleic acids research》2023,51(4):1803
Assembly of ribosomal subunits into active ribosomal complexes is integral to protein synthesis. Release of eIF6 from the 60S ribosomal subunit primes 60S to associate with the 40S subunit and engage in translation. The dynamics of eIF6 interaction with the uL14 (RPL23) interface of 60S and its perturbation by somatic mutations acquired in Shwachman–Diamond Syndrome (SDS) is yet to be clearly understood. Here, by using a modified strategy to obtain high yields of recombinant human eIF6 we have uncovered the critical interface entailing eight key residues in the C-tail of uL14 that is essential for physical interactions between 60S and eIF6. Disruption of the complementary binding interface by conformational changes in eIF6 disease variants provide a mechanism for weakened interactions of variants with the 60S. Hydrogen–deuterium exchange mass spectrometry (HDX-MS) analyses uncovered dynamic configurational rearrangements in eIF6 induced by binding to uL14 and exposed an allosteric interface regulated by the C-tail of eIF6. Disrupting key residues in the eIF6–60S binding interface markedly limits proliferation of cancer cells, which highlights the significance of therapeutically targeting this interface. Establishing these key interfaces thus provide a therapeutic framework for targeting eIF6 in cancers and SDS. 相似文献
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Hanna Kalliolevo Ascelin Gordon Roshan Sharma Joseph W. Bull Sarah A. Bekessy 《Conservation Science and Practice》2021,3(10):e512
Regular contact with nature provides multiple health benefits for people, but biodiversity is declining fast in an urbanizing world. Biodiversity offsets are implemented to compensate for the negative residual impacts of economic development projects on biodiversity, but the impacts on people who stand to lose biodiversity from their local environment are rarely considered. Offsetting typically involves creating, restoring or protecting biodiversity values at a specified site that can be located some distance away from the development site. In this article, we explore whether any relocation of nature is occurring due to development and offsets in Western Australia (WA); a jurisdiction with one of the world's few spatially referenced and comprehensive public offset registers. We analyzed data from 158 projects within the WA Environmental Offsets Register. We compared the location of development sites within 50 km (the urban and peri urban zone) and 500 km (~one day's drive) of the central business district (CBD) of Perth with the associated offset sites. The development and offset process together can be considered to contribute to a loss of urban nature as the offset sites tended to be further away from urban areas than the associated development sites. The offset sites were also located in significantly lower population density areas. However, offsets increased the publicly accessible land area by changing land ownership and creating amenity benefit by improving nature values on public land. Nevertheless, it is unclear to what extent relocation of nature further from people is balanced by increased public access to nature. In order to maintain nature connectedness, ecosystem service delivery and environmental justice in cities, we argue offset policies should require spatial proximity between impact and offset sites. 相似文献
10.
Isabel Regadas Olle Dahlberg Roshan Vaid Oanh Ho Sergey Belikov Gunjan Dixit Sebastian Deindl Jiayu Wen Mattias Mannervik 《Molecular cell》2021,81(8):1766-1780.e10
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