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991.
David Nderu Francis Kimani Kelvin Thiongo Maureen Akinyi Evaline Karanja Christian G. Meyer Thirumalaisamy P. Velavan 《Parasitology international》2018,67(6):793-799
Rapid diagnostic tests (RDT) are valuable tools that support prudent and timely use of antimalarial drugs, particularly if reliable microscopy is not available. However, the performance and reliability of these tests vary between and within geographical regions. The present study evaluated the performance of routine malaria RDT in Kenyan febrile patients in Busia County, Kenya. A cross sectional study design was employed to recruit febrile patients attending health facilities between August and November 2016. A total of 192 febrile patients who were slide positive and negative were evaluated for their infection status by nested PCR and RDTs (PfHRP2/pLDH). In addition, P. falciparum diversity of the histidine-rich proteins 2 and 3, that influences the RDT test results were determined. All individuals were P. falciparum positive. Among the investigated 192 febrile patients, 76 (40%) were positive by microscopy, 101 (53%) by RDTs and 80 (42%) were PCR positive. The performance of the CareStart? HRP2/pLDH (pf) RDTs was better than microscopy (Sensitivity 94%; Specificity 75%) and Nucleic acid testing (sensitivity 95%, specificity 77%) with high negative predictive values, indicating the suitability of the RDT in routine practice. Specific pfhrp2/pfhrp3 deletions shown to associate with RDT false negativity was not observed. However, high genetic diversity among pfhrp2 gene was observed. Eleven new PfHRP2 and nine PfHRP3 repeats were observed. False positivity by microscopy and under reporting of infections may thus be a barrier in malaria control and elimination programs. The HRP2/pLDH(Pf) based RDT yet demonstrate to be an effective tool for malaria surveillance program. 相似文献
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994.
Jessica St-Pierre Philippe J. Dufresne Alex Carignan Émilie Lévesque Francis Bernard Jean Longtin Louiselle LeBlanc 《Mycopathologia》2018,183(2):399-406
We report the two first cases of human C. gattii meningoencephalitis acquired on the Canadian east coast, from the province of Quebec. Unlike C. neoformans, C. gattii is not known to have an established ecological niche on the North American east coast. C. gattii has recently been responsible for major outbreaks in British Columbia, Canada, and in the American pacific northwest. However, no human cases acquired in other Canadian provinces have been reported to our knowledge. The source of acquisition remains unclear for both patients but since neither had traveled outside of the province of Quebec, we discuss the possibilities of environmental and animal-associated acquisition, as well as the possible established endemicity in new areas. These cases add to the growing reported human and animal cases in areas previously not thought to be endemic for C. gattii. 相似文献
995.
Proteins Identified from Saliva and Salivary Glands of the Chinese Gall Aphid Schlechtendalia chinensis
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Zixiang Yang Lin Ma Frederic Francis Ying Yang Hang Chen Haixia Wu Xiaoming Chen 《Proteomics》2018,18(9)
Aphid saliva plays an essential role in the interaction between aphids and their host plants. Several aphid salivary proteins have been identified but none from galling aphids. Here the salivary proteins from the Chinese gall aphid are analyzed, Schlechtendalia chinensis, via an LC‐MS/MS analysis. A total of 31 proteins are identified directly from saliva collected via an artificial diet, and 141 proteins are identified from extracts derived from dissected salivary glands. Among these identified proteins, 17 are found in both collected saliva and dissected salivary glands. In comparison with salivary proteins from ten other free‐living Hemipterans, the most striking feature of the salivary protein from S. chinensis is the existence of high proportion of proteins with binding activity, including DNA‐, protein‐, ATP‐, and iron‐binding proteins. These proteins maybe involved in gall formation. These results provide a framework for future research to elucidate the molecular basis for gall induction by galling aphids. 相似文献
996.
Review on Challenges and Recent Advances in the Electrochemical Performance of High Capacity Li‐ and Mn‐Rich Cathode Materials for Li‐Ion Batteries
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Prasant Kumar Nayak Evan M. Erickson Florian Schipper Tirupathi Rao Penki Nookala Munichandraiah Philipp Adelhelm Hadar Sclar Francis Amalraj Boris Markovsky Doron Aurbach 《Liver Transplantation》2018,8(8)
Li and Mn‐rich layered oxides, xLi2MnO3·(1–x)LiMO2 (M=Ni, Mn, Co), are promising cathode materials for Li‐ion batteries because of their high specific capacity that can exceed 250 mA h g?1. However, these materials suffer from high 1st cycle irreversible capacity, gradual capacity fading, low rate capability, a substantial charge‐discharge voltage hysteresis, and a large average discharge voltage decay during cycling. The latter detrimental phenomenon is ascribed to irreversible structural transformations upon cycling of these cathodes related to potentials ≥4.5 V required for their charging. Transition metal inactivation along with impedance increase and partial layered‐to‐spinel transformation during cycling are possible reasons for the detrimental voltage fade. Doping of Li, Mn‐rich materials by Na, Mg, Al, Fe, Co, Ru, etc. is useful for stabilizing capacity and mitigating the discharge‐voltage decay of xLi2MnO3·(1–x)LiMO2 electrodes. Surface modifications by thin coatings of Al2O3, V2O5, AlF3, AlPO4, etc. or by gas treatment (for instance, by NH3) can also enhance voltage and capacity stability during cycling. This paper describes the recent literature results and ongoing efforts from our groups to improve the performance of Li, Mn‐rich materials. Focus is also on preparation of cobalt‐free cathodes, which are integrated layered‐spinel materials with high reversible capacity and stable performance. 相似文献
997.
Dieu-Hien Truong Hoang Chinh Nguyen Julien Bauwens Gabriel Mazzucchelli Georges Lognay Frédéric Francis 《Journal of Plant Interactions》2018,13(1):30-36
The interactions between Arabidopsis thaliana and Plutella xylostella have been considered as a model system to unravel the responses of plants to herbivorous insects. Here, we use a 2-DE proteome approach to detect protein expression changes in the leaves of Arabidopsis plants exposed to P. xylostella larval infestation at 27°C within 8?h. Approximately 450 protein spots were reproducibly detected on gels. Of these, comparing healthy and infested leaves, we identified 18 differentially expressed protein spots. Thirteen proteins were successfully identified by MALDI-TOF/MS and LC-ESI-MS/MS. Functional classification analysis indicated that the differentially identified proteins were associated with amino acid, carbohydrate, energy, lipid metabolism, and photosynthesis. In addition, their relative abundances were assessed according to larval pest feeding on Arabidopsis leaves. These data provide valuable new insights for further works in plant-biotic and environmental stress interaction. 相似文献
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999.
Generality in multispecies responses to ocean acidification revealed through multiple hypothesis testing
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Allison K. Barner Francis Chan Annaliese Hettinger Sally D. Hacker Kelsey Marshall Bruce A. Menge 《Global Change Biology》2018,24(10):4464-4477
Decades of research have demonstrated that many calcifying species are negatively affected by ocean acidification, a major anthropogenic threat in marine ecosystems. However, even closely related species may exhibit different responses to ocean acidification and less is known about the drivers that shape such variation in different species. Here, we examine the drivers of physiological performance under ocean acidification in a group of five species of turf‐forming coralline algae. Specifically, quantitating the relative weight of evidence for each of ten hypotheses, we show that variation in coralline calcification and photosynthesis was best explained by allometric traits. Across ocean acidification conditions, larger individuals (measured as noncalcified mass) had higher net calcification and photosynthesis rates. Importantly, our approach was able to not only identify the aspect of size that drove the performance of coralline algae, but also determined that responses to ocean acidification were not dependent on species identity, evolutionary relatedness, habitat, shape, or structural composition. In fact, we found that failure to test multiple, alternative hypotheses would underestimate the generality of physiological performances, leading to the conclusion that each species had different baseline performance under ocean acidification. Testing among alternative hypotheses is an essential step toward determining the generalizability of experiments across taxa and identifying common drivers of species responses to global change. 相似文献
1000.
Contribution of the β‐glucosidase BglC to the onset of the pathogenic lifestyle of Streptomyces scabies
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