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BackgroundMicroRNAs (miRNAs) are small, non-coding RNAs capable of postranscriptionally regulating gene expression. Accurate expression profiling is crucial for understanding the biological roles of miRNAs, and exploring them as biomarkers of diseases.Methodology/Principal FindingsA novel, highly sensitive, and reliable miRNA quantification approach,termed S-Poly(T) miRNA assay, is designed. In this assay, miRNAs are subjected to polyadenylation and reverse transcription with a S-Poly(T) primer that contains a universal reverse primer, a universal Taqman probe, an oligo(dT)11 sequence and six miRNA-specific bases. Individual miRNAs are then amplified by a specific forward primer and a universal reverse primer, and the PCR products are detected by a universal Taqman probe. The S-Poly(T) assay showed a minimum of 4-fold increase in sensitivity as compared with the stem-loop or poly(A)-based methods. A remarkable specificity in discriminating among miRNAs with high sequence similarity was also obtained with this approach. Using this method, we profiled miRNAs in human pulmonary arterial smooth muscle cells (HPASMC) and identified 9 differentially expressed miRNAs associated with hypoxia treatment. Due to its outstanding sensitivity, the number of circulating miRNAs from normal human serum was significantly expanded from 368 to 518.Conclusions/SignificanceWith excellent sensitivity, specificity, and high-throughput, the S-Poly(T) method provides a powerful tool for miRNAs quantification and identification of tissue- or disease-specific miRNA biomarkers.

It is well known that the recently developed photoinduced metal-free atom transfer radical polymerization (ATRP) has been considered as a promising methodology to completely eliminate transition metal residue in polymers. However, a serious problem needs to be improved, namely, large amount of organic photocatalysts should be used to keep the controllability over molecular weights and molecular weight distributions. In this work, a novel photocatalyst 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) with strong excited state reduction potential is successfully used to mediate a metal-free ATRP of methyl methacrylate just with parts per million (ppm) level usage under irradiation of blue light emitting diode at room temperature, using ethyl α-bromophenyl-acetate as a typical initiator with high initiator efficiency. The polymerization kinetic study, multiple controlled "on-off" light switching cycle regulation, and chain extension experiment confirm the "living"/controlled features of this promising photoinduced metal-free ATRP system with good molecular weight control in the presence of ppm level photocatalyst 4CzIPN.

Although antimicrobial resistance poses a great challenge to clinicians in China, there are limited antimicrobial resistance data on Gram-negative bacteria nationwide. We investigated the phenotypic characteristics of carbapenem-resistant Escherichia coli (CREC) and Klebsiella pneumoniae (CRKP) as well as extensively drug-resistant strains of Pseudomonas aeruginosa (XDRPA) and Acinetobacter baumannii (XDRAB) isolated from blood cultures in China. Data were collected on 24113 isolates from the China surveillance of antimicrobial resistance program in 2013, which comprised 208 hospitals located in all seven administrative regions of China. Minimum inhibitory concentrations (MICs) for common antimicrobials were determined by commercial automated systems available at local hospitals, and associations with geographic and clinical distributions was further studied. The overall prevalence of CREC, CRKP, XDRAB and XDRPA strains was 1.0, 5.5, 13.7 and 4.2%, respectively. Except for CREC, which did not differ greatly by region, the prevalence of the remaining three strains varied significantly across regions. The highest prevalence of CRKP (10.6%) and XDRAB (13.1%) were found in the pediatric group, and higher prevalence of all four target strains was found in the intensive care unit. For imipenem, 55.8% of CREC and 22.9% of CRKP strains had MICs of ≤4 μg/mL, while 97.4% XDRAB and 84% XDRPA isolates had MICs of ≥16 μg/mL. All CREC, CRKP and 81.2% of XDRAB strains were susceptible to tigecycline, with MIC90 values of 0.5, 2 and 4 μg/mL, respectively. In conclusion, a high prevalence of CRKP and XDRAB has emerged in China, especially in children and in the intensive care unit.

The COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused nations to adopt unprecedented control measures in order to curb its spread.As the first nation to respond, China's aggressive control measures appeared to have been effective in suppressing the first wave and keeping new cases under control. Here, we provide the historical context and details of China's public health response to COVID-19. We highlight the lessons and impact of the 2002-2003 SARS outbreak, which demonstrated the importance of transparency, surveillance and testing laboratories during an outbreak. We provide an overview of China's response strategy that was based on the principles of early detection, isolation, management and treatment and involved not only the largescale coordination of multiple governmental bodies but also grass-root community participation throughout the country. These community-based organizations conducted active surveillance for febrile cases and provided support for those in quarantine and communities in lockdown. Importantly, these broader measures were supported by digital technology, including the extensive use of internet-based platforms and mobile applications (APPs). While there have been no significant increases in case numbers since April, there is still much concern over a second wave, considering the resumption of work and school, the lifting of travel restrictions and the outbreaks occurring globally. Control measures has since been implemented by provincial authorities, which includes continued surveillance and rapid testing. Although China's strict control measures may not suit every nation, the principles of early detection and isolation continue to hold true and have been a cornerstone of the initial and ongoing response to the COVID-19.

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Chemical looping of bio-oil is a promising route to convert this low-quality fuel to pure hydrogen with inherent gas separation and low energy penalty. In that the oil is liable to form coke during the heating process, the current chemical looping cycles usually suffer from low hydrogen purity and poor OC recyclability. In this paper, we proposed a strategy of adding steam in FR to suppress coke formation and enhance the hydrogen purity. To perform the chemical looping cycles, we first built a dual fluidized bed and attained the optimal operating conditions. The results showed the higher hydrogen purity, yield and good recyclability at 950 °C. Afterwards, we investigated effects of the steam to oil ratios on hydrogen purity, yield and the recyclability of oxygen carrier, and found adding steam in the fuel reactor was an efficiency way to enhance the hydrogen purity. The results suggested the hydrogen purity can reach 98%; nevertheless, it suppressed the hydrogen yield simultaneously. In terms of the redox performance of oxygen carrier, we also found the steam can weaken the reduction reactions, and therefore increased the particle recyclability. Our current study suggested the enhancement of the hydrogen purity was at the cost of the suppression in hydrogen yield, and we need to find a compromise between the hydrogen yield and the purity to pursue high system efficiency.

Background: Berberine (BBR) plays a neuroprotective role in the pathogenesis of Alzheimer’s disease (AD), inhibiting amyloid-β (Aβ) production and promoting Aβ clearance. Advanced glycation end products (AGEs) promote Aβ aggregation and tau hyperphosphorylation. The activation of mTOR signaling occurring at the early stage of AD has a prominent impact on the Aβ production. This work focused on whether BBR regulates the production and clearance of ribosylation-induced Aβ pathology via inhibiting mTOR signaling. Objective: To explore whether BBR ameliorates ribosylation-induced Aβ pathology in APP/PS1 mice. Methods: Western blot and immunofluorescence staining were used to detect the related proteins of the mammalian target of Rapamycin (mTOR) signaling pathway and autophagy, as well as the related kinases of Aβ generation and clearance. Tissue sections and Immunofluorescence staining were used to observe Aβ42 in APP/PS1 mice hippocampal. Morris water maze test was used to measure the spatial learning and memory of APP/PS1 mice. Results: BBR improves spatial learning and memory of APP/PS1 mice. BBR limits the activation of mTOR/p70S6K signaling pathway and enhances autophagy process. BBR reduces the activity of BACE1 and γ-secretase induced by D-ribose, and enhances Aβ-degrading enzymes and Neprilysin, and inhibits the expression of Aβ in APP/PS1 mice. Conclusion: BBR ameliorates ribosylation-induced Aβ pathology via inhibiting mTOR/p70S6K signaling and improves spatial learning and memory of the APP/PS1 mice.