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[Display omitted] Surface-associated microbe contamination by Gram-negative bacteria poses a serious problem in medical care. Cationic peptides or polymers are the main materials used for antibacterial surface coating, but the positive charge may lead to blood coagulation. Therefore, exploiting surface coating which is free of positive charge and is effective for Gram-negative bacteria inactivation is in urgent need. In this study, inspired by the affinity between lipopolysaccharides of Gram-negative bacteria and Toll-like receptors of immune cells, we develop a leucine-based tetrapeptide coating strategy for combating Gram-negative bacteria. The obtained surface has excellent bactericidal activity against Gram-negative bacteria like Pseudomonas aeruginosa and Escherichia coli. A 1 mm2 coated glass surface could kill > 9.9 × 104 CFU bacteria in 1 h and has nearly no damage to mammal cells. Moreover, this surface coating strategy could be applied on various surfaces like glass slices, glass capillary cavity and thermoplastic polyurethane slices. And the coated surface could largely mitigate the microbe contamination in an in vivo subcutaneous implantation. This work paves a new way for antibacterial surface-coating which is behaving no positive charge and is of great importance for biomedical devices. [ABSTRACT FROM AUTHOR]

Abstract The two-spotted spider mite, Tetranychus urticae Koch, is a serious agricultural pest that has developed resistance to many pesticides. A leaf dip assay was used to assess the resistance of seven field populations of T. urticae to 11 pesticides in China. The mutation frequencies of target genes related to pesticide resistance were also determined. The results showed that all seven field populations had high or extremely high resistance to abamectin and had low or moderate resistance to newly developed pesticides including bifenazate, cyenopyrafen, chlorfenapyr, B-azolemiteacrylic, and spinetoram. The RF values for the traditional acaricides bifenthrin, pyridaben, and profenofos were low for all seven populations. For target sites related to abamectin resistance, the frequency of the mutations ranged from 28.33 to 63.64% for G314D in the glutamate-gated chloride channel gene 1 (GluCl1), and from 0 to 95% for G326E in the glutamate-gated chloride channel gene 3 (GluCl3). For target sites related to organophosphate resistance, the frequency of mutations ranged from 33.33 to 56.67% for G119S and from 5.00 to 43.33% for A201S in the acetycholinesterase gene (Ace). For target sites related to pyrethroid resistance, the frequency of the mutations ranged from 76.67 to 98.33% for A1215D and from 3.33 to 100% for F1538I in the voltage-gated sodium channel gene (VGSC). No mutations were detected in the bifenazate resistance-related cytochrome b gene (Cytb). These results will be useful for managing T. urticae resistance to pesticides in China. Graphical abstract Unlabelled Image Highlights • Multiple levels of resistance to insecticides were observed in the field populations of Tetranychus urticae in China. • The mutation frequencies of GluCl, Ace, VGSC genes differed among the populations. • No mutations were detected for the Cytb gene. [ABSTRACT FROM AUTHOR]

Persistent exposure of emerging contaminants (ECs) in freshwater ecosystem has initiated intense global concerns. Freshwater ecosystem dominated by submerged plants (SP-FES) has been widely constructed to control eutrophic water. However, the environmental behaviors (e.g. migration, transformation, and degradation) of ECs in SP-FES have rarely been concerned and summarized. This review briefly introduced the sources of ECs, the pathways of ECs entering into SP-FES, and the constituent elements of SP-FES. And then the environmental behaviors of dissolved ECs and refractory solid ECs in SP-FES were comprehensively summarized, and the feasibility of removing ECs from SP-FES was critically evaluated. Finally, the challenges and perspectives on the future development for ECs removal from SP-FES were prospected, giving possible research gaps and key directions. This review will provide theoretical and technical support for the effective removal of ECs in freshwater ecosystem, especially in SP-FES. [Display omitted] • Freshwater ecosystem dominated by submerged plants (SP-FES) was reviewed firstly. • Environmental behaviors of emerging contaminants (ECs) were summarized. • Dissolved ECs and refractory solid ECs could be effectively removed by SP-FES. • The development directions of SP-FES for ECs removal were prospected. [ABSTRACT FROM AUTHOR]

Abstract: RNA interference (RNAi) mediated by microRNA (miRNA) is an evolutionarily conserved mechanism of posttranscriptional gene regulation in all eukaryotes, involving in natural antiviral immunity. The RNAase III Drosha is a key component for miRNA maturation. To date, however, the roles of Drosha in virus infection remain to be addressed. In this study, the Drosha was characterized in Marsupenaeus japonicus shrimp. The sequence analysis revealed that the shrimp Drosha gene encoded a 1081-amino-acid peptide, which comprised two tandem ribonuclease III C terminal domains and a double-stranded RNA binding motif. The shrimp Drosha was homologous with those of other animal species. The quantitative RT-PCR analysis revealed that the Drosha gene was highly expressed in lymphoid organ and was significantly up-regulated in response to WSSV challenge, suggesting that the Drosha was involved in the antiviral immunity of shrimp. The results showed that the knock down of Drosha gene led to the defect of miRNA maturation, and subsequent higher virus loads in shrimp. Our study presented that Drosha played important roles in the antiviral defense of shrimp. [Copyright &y& Elsevier]

Red sufu is a traditional food produced by the fermentation of soybean. In this study, sufu samples were periodically collected during the whole fermentation to investigate the dynamic changes of fungal and bacterial communities using high-throughput sequencing technology. The overall process can be divided into pre- and post-fermentation. During post-fermentation, the pH value showed a gradual decrease over time while the amino nitrogen content increased. Trichosporon , Actinomucor and Cryptococcus were the main genera in pre-fermentation while Monascus and Aspergillus were dominant in post-fermentation. This huge shift in fungal composition was caused by process procedure of pouring dressing mixture. However, the bacterial composition was not greatly changed after pouring dressing mixture, the Acinetobacter and Enterobacter were the predominant genera throughout the whole process. Furthermore, Bacillus species were first detected after adding dressing mixture, but declined abruptly to a very low level (0.07%) by the end of the fermentation. Our work demonstrates the dynamic changes of physicochemical properties and microbial composition in every fermentation stage, the knowledge of which could potentially serve as a foundation for improving the safety and quality of sufu in the future. • Trichosporon , Actinomucor and Cryptococcus were the main genera in pre-fermentation. • Monascus and Aspergillus were the dominant genus in post-fermentation. • Acinetobacter and Enterobacter were the predominant genus throughout the whole fermentation process. • Bacillus were first detected after adding dressing mixture, but declined to a very low level by the end of fermentation. [ABSTRACT FROM AUTHOR]

• Taste profiles of Monascus rice vinegar were evaluated. • Seven organic acids and four FAAs were taste active indicators. • Correlation of taste active indicators and antioxidant activity was performed. • Seven key components were taste active indicators of antioxidant activity. The present study evaluated the changes of taste profiles, taste active indicators, and antioxidant activity in Monascus rice vinegar during the solid-state fermentation process, as well as their potential relationships. The results showed that the contents of antioxidant components and antioxidant activity increased with fermentation time. According to the taste active value (TAV) evaluation, seven organic acids and four free amino acids (FAAs) with high TAVs were considered as taste active indicators. The correlation analysis between antioxidant activity and major antioxidant compounds in Monascus rice vinegar followed the order: FAAs＞total phenols＞total flavonoids＞organic acids. Further analysis revealed that seven key components including acetic acid, lactic acid, tartaric acid, succinic acid, Glu, Ala, and Val were taste active indicators of antioxidant activity, which had significant effects on the taste characteristic and antioxidant activity in Monascus rice vinegar. Thus, our findings would provide references to regulate the antioxidant characteristic of Monascus rice vinegar through the key taste active indicators, and would provide new insights to further explore the development of new vinegar-based functional foods. [ABSTRACT FROM AUTHOR]

Because of micro/nanoscale manipulation and task-performing capability, micro/nanomotors (MNMs) have attracted lots of research interests for potential applications in biomedical and environmental applications. Owing to the low-cost, good motion behavior, and environmental friendliness, various low-cost metal oxides based MNMs become promising alternatives to the precious metal based MNMs, in particular for environmental remediation applications. Hereby, we demonstrate the facile and scalable fabrication of two types of bubble-propelled iron oxides-MnO 2 core–shell micromotors (Fe 3 O 4 -MnO 2 and Fe 2 O 3 -MnO 2) for pollutant removal. The Fe 2 O 3 -MnO 2 micromotor exhibits efficient removals of both aqueous organics and suspended microplastics via the synergy of catalytic degradation, surface adsorption, and adsorptive bubbles separations mechanisms. The adsorptive bubbles separation achieved more than 10% removal of the suspended microplastics from the polluted water in 2 h. We clarified the major contributions of different remediation mechanisms in pollutants removals, and the findings may be beneficial to a wide range of environmental applications of MNMs. [ABSTRACT FROM AUTHOR]

The rapid evolution of pest resistance threatens the sustainable utilization of bioinsecticides such as abamectin, and so deciphering the molecular mechanisms affecting toxicity and resistance is essential for their long-term application. Historical studies of abamectin resistance in arthropods have mainly focused on mechanisms involving the glutamate-gated chloride channel (GluCl) targets, with the role of metabolic processes less clear. The two-spotted spider mite, Tetranychus urticae , is a generalist herbivore notorious for rapidly developing resistance to pesticides worldwide, and abamectin has been widely used for its control in the field. After reanalyzing previous transcriptome and RNA-seq data, we here identified an ABC transporter subfamily C gene in T. urticae named multidrug resistance-associated protein 1 (TuMRP1), whose expression differed between susceptible and resistant populations. Synergism bioassays with the inhibitor MK-571, the existence of a genetic association between TuMRP1 expression and susceptibility to abamectin, and the effect of RNA interference mediated silencing of TuMRP1 were all consistent with a direct role of this transporter protein in the toxicity of abamectin. Although ABC transporters are often involved in removing insecticidal compounds from cells, our data suggest either an alternative role for these proteins in the mechanism of action of abamectin or highlight an indirect association between their expression and abamectin toxicity. [Display omitted] • A novel ABCC transporter gene (TuMRP1) was cloned in Tetranychus urticae. • The spatial-temporal expression pattern of TuMRP1 was analyzed. • TuMRP1 expression levels were significantly decreased in resistant strains. • TuMRP1 silencing significantly reduced susceptibility to abamectin in T. urticae. • TuMRP1 reduction is indirectly associated with abamectin toxicity in T. urticae. [ABSTRACT FROM AUTHOR]

Background Many multi-center epidemiological studies have robustly examined the acute health effects of exposure to low concentrations of fine particulate matter (PM 2.5 ) on cardiovascular mortality in developed counties. However, data limitations have resulted in few related studies being conducted in developing counties with high levels of PM 2.5 exposure. In recent years, people in China with a heavy cardiovascular disease burden have been exposed to particularly high levels of PM 2.5 . Objective We conducted a multi-county time series study investigating the acute effects of PM 2.5 on the increased risk of cardiovascular death across China, and explored subpopulations susceptible to PM 2.5 exposure. Methods Appling a county-specific Poisson regression in 30 Chinese counties, we estimated PM 2.5 effects on all-cause mortality and cause-specific mortality of cardiovascular health for 2013–2015. We also considered PM 2.5 effects on several subpopulations, including males, females, and three age groups (< 65, 65–74 and > 74 years old). We pooled the county-specific results across China using a random effects meta-analysis by cause and by subpopulation. Results We found a 0.13% (95% confidence interval (CI), 0.04–0.22) increase in all-cause mortality, a 0.12% increase (95% CI, 0.001–0.25) increase in cardiovascular disease (CVD), a 0.42% (95% CI, 0.03–0.81) increase in AMI, a 0.17% (95% CI, −0.04–0.40) increase in coronary heart disease, and a 0.13% (95% CI, −0.12–0.33) increase in stroke in association with a 10-μg/m 3 increase in PM 2.5 concentrations on the same day. The magnitudes of the associations were less than those reported in developed counties with lower PM 2.5 levels. A vulnerable effect on all-cause mortality was observed in the elderly population (older than 65 years) and on CVD in males. Conclusions This study showed the positive magnitude of PM 2.5 effects with high exposure on all natural, CVD, and cause-specific mortality and on the susceptible populations in China. The findings complemented evidence related to exposure-mortality relationships at the higher end of short-term exposure to PM 2.5 on a global scale. [ABSTRACT FROM AUTHOR]