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Porcine reproductive and respiratory syndrome virus (PRRSV) is an RNA virus that causes great economic losses globally to the swine industry. Innate immune RNA receptors mainly sense it during infection. As a DNA sensor, cyclic GMP-AMP synthase (cGAS) plays an important role in sensing cytosolic DNA and activating innate immunity to induce IFN-I and establish an antiviral cellular state. In contrast, the role of innate immune DNA sensors during PRRSV infection has not been elucidated. In this study, we found that cGAS facilitates the production of IFN-β during PRRSV infection. Western blot and virus titer assays suggested that cGAS overexpression suppressed the replication of multiple PRRSV strains, while knockout of cGAS increased viral titer and nucleocapsid protein expression. Besides, our results indicated that the mitochondria were damaged during PRRSV infection and leaked mitochondrial DNA (mtDNA) into the cytoplasm. The mtDNA in the cytoplasm co-localizes with the cGAS, and the cGAMP activity was increased when the cGAS was overexpressed during PRRSV infection. Furthermore, the cGAMP also possesses an anti-PRRSV effect. These results indicate for the first time that cGAS restricts PRRSV replication by sensing the mtDNA in the cytoplasm to increase cGAMP activity, which not only explains the molecular mechanism by which cGAS inhibits PRRSV replication but also provides research ideas for studying the role of the cGAS-STING signaling pathway in the process of RNA virus infection.

Background Radiotherapy is one of the essential components of breast cancer treatment. It destroys the remaining cells in the chest area after breast cancer surgery and is useful for reducing the necessity of mastectomies. As a single dose of radiation at the time of breast conserving surgery, intraoperative radiotherapy delivers radiotherapy directly and accurately to the tumor itself or the tumor bed whilst delivering minimal dose to the surrounding normal tissues. Hypofractionated postmastectomy radiotherapy with shorter and more convenient hypofractionated dose schedules might help to treat more patients and reduce cost. We will conduct a comprehensive systematic review and meta-analysis to compare the effectiveness of these 2 therapies in the management of early stage breast cancer. Methods Four English databases (PubMed, Embase, Cochrane Library, and Web of Science) and 3 Chinese databases (China National Knowledge Infrastructure, China Science and Technology Journal Database, and Chinese Biomedical Literature Database) will be searched from inception of databases to December 2020 without language limitation. Two reviewers will independently conduct selection of studies, data extraction and management, and assessment of risk of bias. Any disagreement will be resolved by the third reviewer. Review Manager 5.3 (The Cochrane Collaboration, Software Update, Oxford, UK) will be used for data synthesis. Cochrane risk of bias assessment tool will be used to assess the risk of bias. Results This study will provide a systematic synthesis of current published data to compare the effectiveness of intraoperative radiotherapy vs hypofractionated postmastectomy radiotherapy for early stage breast cancer. Conclusions This systematic review and meta-analysis will provide clinical evidence for the effectiveness of intraoperative radiotherapy vs hypofractionated postmastectomy radiotherapy for early stage breast cancer, and inform our understanding of the value of intraoperative radiotherapy and hypofractionated postmastectomy radiotherapy for early stage breast cancer. Study registration number INPLASY2020110115.

Biofiltration of hydrophobic and/or recalcitrant volatile organic compounds in industry is currently limited. A laboratory-scale system integrating ultraviolet (UV) photodegradation and a biotrickling filter (BTF) was developed to treat dichloromethane (DCM), and this was compared to BTF alone. A combined UV-BTF approach permitted faster biofilm formation and greater removal than BTF. DCM distribution and its photodegradation intermediates revealed that the lower filter of the UV-BTF contributed more to CO2 production; the upper filter assisted more with DCM removal. The UV-BTF kept secretion of extracellular polymeric substances at a normal level with an evenly distributed biomass. Pyrosequencing analysis showed that the dominant population in the combined biofilter was more diverse than that in BTF alone. Our data provide a foundation for understanding the effect of UV pretreatment on BTF performance and the microbial community.

Ultraviolet photodegradation (UV) was utilized as a pretreatment to enhance the biofiltration process (BF and BTF) for the removal of hydrophobic α-pinene. Based on the experimental data, the mass transfer behavior and microbial activity were analyzed by the theoretical models. The gas phase saturated constant K m of α-pinene was 1.0 g m -3 in the UV-BTF, 20 times than that in the sole BTF; while this value in the sole BF was slightly higher than that in the UV-BF. Fitted by the Ottengraf-van den Oever model, the critical inlet concentration in the UV-BTF was 555.22 mg m -3 , which was much higher than that in other systems. Through the analysis of microbial activity and specific oxygen utilization rate, the biofilm in the UV-BTF was much more active, and the maximum specific oxygen utilization rates for α-pinene and its photodegradation intermediates were respectively 1.16, 0.34, 0.41and 0.25 mgO 2 mg -1 DW h -1 , slightly higher than 150%–200% of the values in other systems. Such results illustrated that UV photodegradation could reduce the mass transfer inhibition for α-pinene and simulate the growths of microorganisms in the subsequent BTF, thus enhancing the overall removal capabilities. But the UV technology was not a suitable pretreatment for the subsequent BF owing to BF’s own characteristics and cumulative toxic effects of ozone.

Chironomus kiiensis larvae, which cannot be exterminated by conventional disinfection processes, propagate prolifically in eutrophic water bodies, therefore posing a potential problem for drinking water quality. In this work, quantitative experimental studies were carried out on inactivation of Chironomus kiiensis larvae using conventional oxidants of chlorine (Cl 2 ), chlorine dioxide (ClO 2 ) and ozone under conditions of different oxidant dosages, organic precursor concentration and pH values. The results showed that three oxidants used could inactivate Chironomus kiiensis larvae to some extent. Chlorine and chlorine dioxide were proved to be the least and most efficient oxidant for inactivating Chironomus kiiensis larvae, respectively. In addition, the synergic removal effects with pre-oxidation followed by conventional water treatment processes were also evaluated. The results showed that pre-oxidation could lead to enhanced removal of the inactivated organism by the subsequent coagulation process while lowering the dosage of oxidant. In view of the need to secure drinking water quality, it is necessary to combine oxidant inactivation with conventional processes for removing Chironomus kiiensis larvae from micro-polluted water sources.

In Wuxi Wastewater Treatment Plant, the Anaerobic, anoxic and oxic (A2/O) process was employed to remove the nitrogen and phosphorus, which exhibited the positive results of the high removal efficiency for phosphorus with a range of 67.7% to 89.9% and an average value of 78.0. The effluent of phosphorus met the national discharge standard. The removal of TN was effected by both BOD variation of influent and wastewater temperature. TN removal was in the range of 28.5% to 55.8% with an average value of 39.4%. The energy cost was 0.15 kWh (m3d)−1 or 1.35 kWh (kgBOD·d)−1. The annual average sludge production was 46.3 m3d−1, the annual average dosage for dewatering was 40 kg d−1.

PCR-DGGE was applied to analyze the microbial communities in rotating drum biofilter (RDB) for nitric oxide denitrifying removal under anaerobic conditions. The 16S rRNA genes (V3 region) were amplified with two universal primers (338F-GC and 518R). These amplified DNA fragments were separated by parallel DGGE. The DGGE profiles of biofilm samples from different sections of RDB are similar and about sixteen types of microorganisms are identified in the biofilm samples. These results show that microbial diversity of RDB firstly increases but then decreases with the addition of Cu II (EDTA) and the increase of NO removal efficiency. However, the change of microbial community is not significant during the process. Eight major bands of 16S rRNA genes fragments from DGGE profiles of biofilm samples were further eluted from gel, re-amplified, cloned and sequenced. The sequences of these fragments were compared with the database in GeneBank (NCBI). The gene analysis of 16S rRNA showed that the major populations are Cytopahga-Flexibacteria-Bacteroides (CFB) group Bacteroides, beta -Proteobacterium, gamma-Proteobacterium and Clostridium sp.. In addition, denitrification is related with band G-5, G-6 and G-8. G-5 is affiliated with gamma-Proteobacterium. Both G-6 and G-8 are affiliated with beta-Proteobacterium.