Circulating RNA Molecules as Biomarkers in Liver Disease

Liver disease is a major cause of morbidity and mortality worldwide. As in other fields of medicine, there is a stringent need for non-invasive markers to improve patient diagnostics, monitoring and prognostic ability in liver pathology. Cell-free circulating RNA molecules have been recently acknowledged as an important source of potential medical biomarkers. However, many aspects related to the biology of these molecules remain to be elucidated. In this review, we summarize current concepts related to the origin, transportation and possible functions of cell-free RNA. We outline current development of extracellular RNA-based biomarkers in the main forms of non-inherited liver disease: chronic viral hepatitis, hepatocellular carcinoma, non-alcoholic fatty liver, hepato-toxicity, and liver transplantation. Despite recent technological advances, the lack of standardization in the assessment of these markers makes their adoption into clinical practice difficult. We thus finally review the main factors influencing quantification of circulating RNA. These factors should be considered in the reporting and interpretation of current findings, as well as in the proper planning of future studies, to improve reliability and reproducibility of results.     

Bimodal X‐ray and Infrared Imaging of an Organometallic Derivative of Praziquantel in Schistosoma mansoni

An organometallic derivative of praziquantel was studied directly in worms by using inductively coupled plasma‐mass spectrometry (ICP‐MS) for quantification and synchrotron‐based imaging. X‐ray fluorescence (XRF) and IR absorption spectromicroscopy were used for the first time in combination to directly locate this organometallic drug candidate in schistosomes. The detection of both CO (IR) and Cr (XRF) signatures proved that the Cr(CO)₃ core remained intact in the worms. Images showed a preferential accumulation at the worm's tegument, consistent with a possible targeting of the calcium channel but not excluding other biological targets inside the worm.     

Energy harvest with mangrove benthic microbial fuel cells

Benthic microbial fuel cells (BMFCs) are continuous electricity generators using electroactive microorganisms and organic matter from aquatic environment, respectively, as catalysts and substrate. In this paper, first a low‐cost PVC‐made structure is constructed to harvest electricity from mangrove environment located in French Guiana. An in situ BMFC has given power density of 30 mW/m² of the anodic surface area. This performance has been confirmed by experience in laboratory where inter‐electrode distance and electrode surface area appeared to be power increasing factors. However, the output power of one BMFC is not used to supply real devices such as autonomous sensors. Second, to meet this expectation, in parallel and in series associations were considered. These associations were made in order to increase the output voltage and consequently the power, to reach levels that can supply small sensors (about 3 V). Finally, to improve the performance of the series association and to avoid the voltage reversal phenomenon, a voltage balancing circuit was simulated and added to the series connections. With balancing method, the cell voltage of BMFCs can be equalized, and the performances can be improved. This allows an optimal energy harvesting and a better global efficiency of the set. Copyright © 2014 John Wiley & Sons, Ltd.     

驱动LED串的DCM升压转换器简化分析(1)——理论分析

固定频率升压转换器采用不连续导电模式(DCM)工作,能够有效地用于快速调光操作,提供比采用连续导电模式(CCM工作的竞争器件更优异的瞬态响应,这种转换器非常适合于以恒流模式驱动LED串。但驱动LED的升压转换器的交流分析,与使用标准电阻型负载的升压转换器的交流分析不同,在推导最终的传递函数时必须非常审慎。本文分为两个单元:⑴理论分析,介绍如何推导驱动LED串的升压转换器的小信号响应;⑵实际考虑,深入研究实施方案,并验证经验结果及与理论推导比较。     

Microstructural Investigations of the White and Deformed Layers Close to the Turned Surface of Ti-6Al-4V

In the aircraft industry, along with geometrical and dimensional integrity, the surface integrity of manufactured parts is a necessity. In fact, severe anomalies generated during machining may have a substantial impact on the lifetime of the parts. Nevertheless, these anomalies are not well known in terms of microstructures such as the white layer in titanium alloys. Based on this observation, the present paper deals with microstructural investigations performed on Ti-6Al-4V white and deformed layers generated during turning with a round uncoated carbide insert. The aim of this study is to characterize these anomalies in terms of microstructure and phases. In particular, this study provides a better understanding of metallurgical transformations in the sublayer of machined surfaces through qualitative models.

     

Duplex High-Resolution Melting Assay for the Simultaneous Genotyping of IL28B rs12979860 and PNPLA3 rs738409 Polymorphisms in Chronic Hepatitis C Patients

Chronic hepatitis C (CHC) is a major burden for public health worldwide. Although newer direct-acting antivirals show good efficacy, their cost precludes their wide adoption in resource-limited regions. Thus, strategies are being developed to help identify patients with high susceptibility to response to classic PEG-interferon + ribavirin therapy. IL28B polymorphism rs12979860 C/T is an important predictor for an efficient response to interferon-based therapy. A genetic variant in adiponutrin (PNPLA3) gene, rs738409 C/G, is associated with steatosis, severity, and progression of liver fibrosis in CHC patients, and predicts treatment outcome in difficult-to-cure HCV-infected patients with advanced fibrosis. We developed a rapid and inexpensive assay based on duplex high-resolution melting (HRM) for the simultaneous genotyping of these two polymorphisms. The assay validation was performed on synthetic DNA templates and 132 clinical samples from CHC patients. When compared with allele-specific PCR and sequencing, our assay showed 100% (95% CI: 0.9724–1) accuracy, with 100% sensitivity and specificity. Our assay was robust against concentration and quality of DNA samples, melting curve normalization intervals, HRM analysis algorithm, and sequence variations near the targeted SNPs (single nucleotide polymorphism). This duplex assay should provide useful information for patient-oriented management and clinical decision-making in CHC.     

Synthesis Optimization and Catalytic Activity Screening of Industrially Relevant Ruthenium-Based Metathesis Catalysts

Olefin metathesis is a powerful catalytic reaction that has a huge potential in the pharmaceutical, polymer and specialty chemicals industries. Cost-effective industrial applications require large-scale availability of catalyst precursors which combine high activity, high selectivity and long life-time. Among the known numerous families of olefin metathesis catalysts, the Umicore M7-catalyst family represents a novel class of Hoveyda-type complexes showing excellent chemical stabilities and modular activity profiles. Relevant aspects related to their industrial synthesis as well as their catalytic performance in valuable olefin metathesis transformations are overviewed here.