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Brunner R Aissaoui H Boss C Bozdech Z Brun R Corminboeuf O Delahaye S Fischli C Heidmann B Kaiser M Kamber J Meyer S Papastogiannidis P Siegrist R Voss T Welford R Wittlin S Binkert C 《The Journal of infectious diseases》2012,206(5):735-743
The increasing spread of drug-resistant malaria strains underscores the need for new antimalarial agents with novel modes of action (MOAs). Here, we describe a compound representative of a new class of antimalarials. This molecule, ACT-213615, potently inhibits in vitro erythrocytic growth of all tested Plasmodium falciparum strains, irrespective of their drug resistance properties, with half-maximal inhibitory concentration (IC(50)) values in the low single-digit nanomolar range. Like the clinically used artemisinins, the compound equally and very rapidly affects all 3 asexual erythrocytic parasite stages. In contrast, microarray studies suggest that the MOA of ACT-213615 is different from that of the artemisinins and other known antimalarials. ACT-213615 is orally bioavailable in mice, exhibits activity in the murine Plasmodium berghei model and efficacy comparable to that of the reference drug chloroquine in the recently established P. falciparum SCID mouse model. ACT-213615 represents a new class of potent antimalarials that merits further investigation for its clinical potential. 相似文献
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Studer V Bobin J Chahid M Mousavi HS Candes E Dahan M 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(26):E1679-E1687
The mathematical theory of compressed sensing (CS) asserts that one can acquire signals from measurements whose rate is much lower than the total bandwidth. Whereas the CS theory is now well developed, challenges concerning hardware implementations of CS-based acquisition devices--especially in optics--have only started being addressed. This paper presents an implementation of compressive sensing in fluorescence microscopy and its applications to biomedical imaging. Our CS microscope combines a dynamic structured wide-field illumination and a fast and sensitive single-point fluorescence detection to enable reconstructions of images of fluorescent beads, cells, and tissues with undersampling ratios (between the number of pixels and number of measurements) up to 32. We further demonstrate a hyperspectral mode and record images with 128 spectral channels and undersampling ratios up to 64, illustrating the potential benefits of CS acquisition for higher-dimensional signals, which typically exhibits extreme redundancy. Altogether, our results emphasize the interest of CS schemes for acquisition at a significantly reduced rate and point to some remaining challenges for CS fluorescence microscopy. 相似文献
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Shah FK Gebreel A Elshokouki AH Habib AA Porwal A 《The journal of advanced prosthodontics》2012,4(2):61-71
PURPOSE
To compare the changes in the occlusal vertical dimension, activity of masseter muscles and biting force after insertion of immediate denture constructed with conventional, tooth-supported and Implant-supported immediate mandibular complete denture.MATERIALS AND METHODS
Patients were selected and treatment was carried out with all the three different concepts i.e, immediate denture constructed with conventional (Group A), tooth-supported (Group B) and Implant-supported (Group C) immediate mandibular complete dentures. Parameters of evaluation and comparison were occlusal vertical dimension measured by radiograph (at three different time intervals), Masseter muscle electromyographic (EMG) measurement by EMG analysis (at three different positions of jaws) and bite force measured by force transducer (at two different time intervals). The obtained data were statistically analyzed by using ANOVA-F test at 5% level of significance. If the F test was significant, Least Significant Difference test was performed to test further significant differences between variables.RESULTS
Comparison between mean differences in occlusal vertical dimension for tested groups showed that it was only statistically significant at 1 year after immediate dentures insertion. Comparison between mean differences in wavelet packet coefficients of the electromyographic signals of masseter muscles for tested groups was not significant at rest position, but significant at initial contact position and maximum voluntary clench position. Comparison between mean differences in maximum biting force for tested groups was not statistically significant at 5% level of significance.CONCLUSION
Immediate complete overdentures whether tooth or implant supported prosthesis is recommended than totally mucosal supported prosthesis. 相似文献57.
Phenotyping is commonly used for detection of extended-spectrum beta-lactamase (ESBL) production in gram-negative isolates. ESBLs are mainly coded for by four important genes, namely bla (TEM), bla (SHV), bla (CTX-M), and bla (OXA). Our aim in this study is to assess use of a multiplex PCR as a rapid method to identify four common genes responsible for ESBL production in different gram-negative isolates. All 793 clinical isolates are subjected to both screen and confirmatory testing for ESBL production using double disc synergy testing (DDST). Two hundred isolates with the ESBL phenotype are subjected to multiplex PCR for detection of the four genes bla (TEM, SHV, CTX-M, and OXA). The isolates were obtained from various clinical specimens: 68 (34 %) were isolated from urine cultures, 43 (21.5 %) from sputum, 26 (13 %) from wounds, 34 (17 %) from blood culture, 20 (10 %) from stool of healthy carrier and nine (4.5 %) from bronchoalveolar lavages. In this study, 83 isolates (41.5 %) were from outpatients (urine and stool specimens only), and the remaining 117 isolates (58.5) were from inpatients. By PCR technique, 181 isolates were found to be ESBL producers. blaTEM was the commonest genotype (39.2 %), followed by blaSHV (32.5 %) and blaCTX-M (30.9 %), either alone or in combination. Acinetobacter baumannii isolate had none of the ESBL genes. Eighteen (9.9 %) out of 181 isolates carried more than one type of beta-lactamase genes. Our study demonstrated rapid detection of bla (TEM, SHV, CTX-M, and OXA) in isolates belonging to Enterobacteriaceae and other nonfermenting clinical isolates using multiplex PCR. This genotypic method provided a rapid and efficient differentiation of ESBLs in the laboratory. 相似文献
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Developments in the fields of lab-on-a-chip and microfluidic technology have benefited nanomaterial production processes due to fluid miniaturization. The ability to acquire, manage, create, and modify structures on a nanoscale is of great interest in scientific and technological fields. Recently, more attention has been paid to the production of core–shell nanomaterials because of their use in various fields, such as drug delivery. Heterostructured nanomaterials have more reliable performance than the individual core or shell materials. Nanoparticle synthesis is a complex process; therefore, various techniques exist for the production of different types of nanoparticles. Among these techniques, microfluidic methods are unique and reliable routes, which can be used to produce nanoparticles for drug delivery applications.Developments in the fields of lab-on-a-chip and microfluidic technology have benefited nanomaterial production processes due to fluid miniaturization. 相似文献