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Abstract A-to-I mRNA editing in animals is mediated by ADARs, but the mechanism underlying sexual stage-specific A-to-I mRNA editing in fungi remains unknown. Here, we show that the eukaryotic tRNA-specific heterodimeric deaminase FgTad2-FgTad3 is responsible for A-to-I mRNA editing in Fusarium graminearum. This editing capacity relies on the interaction between FgTad3 and a sexual stage-specific protein called Ame1. Although Ame1 orthologs are widely distributed in fungi, the interaction originates in Sordariomycetes. We have identified key residues responsible for the FgTad3-Ame1 interaction. The expression and activity of FgTad2-FgTad3 are regulated through alternative promoters, alternative translation initiation, and post-translational modifications. Our study demonstrates that the FgTad2-FgTad3-Ame1 complex can efficiently edit mRNA in yeasts, bacteria, and human cells, with important implications for the development of base editors in therapy and agriculture. Overall, this study uncovers mechanisms, regulation, and evolution of RNA editing in fungi, highlighting the role of protein-protein interactions in modulating deaminase function.

Abstract Reduced salinity is a major factor that causes macrobenthic degradation in reclaimed wetlands. We investigated populations of the sesarmid crab Chiromantes dehaani in reclaimed and natural wetlands. Then, in the laboratory, we exposed male and female crabs to four salinity levels (0, 6, 12 and 18) for 96 h to analyse the effects of reduced salinity on osmoregulatory enzyme activities in the posterior gills and digestive and immune enzyme activities in the hepatopancreas of C. dehaani. The results revealed a significant positive correlation between the number of crabs and salinity. In the laboratory, we found that the isosmotic point of C. dehaani was close to 16 ppt. The crabs showed strong hyper-osmotic regulation when exposed to 0–6 ppt salinities. Moreover, in this salinity range, amylase activities were significantly inhibited. Under low-salinity stress, the immune enzyme activities were significantly activated. However, phenoloxidase and lysozyme activities were inhibited in the freshwater environment. The male and female crabs showed no significant differences in most of the enzyme activities. Thus, reduced salinity can adversely affect the digestive and immune functions of C. dehaani, which may cause population degradation in reclaimed wetlands. Our findings can provide new insights into the effects of reclamation on macrobenthos.

Abstract To check if it is possible for crayfish to reduce the weed biomass in a paddy field, we hypothesised that crayfish can feed on common weeds in a paddy field. The feeding ability of red swamp crayfish, Procambarus clarkii, males and females for 4 weeds, Ludwigia prostrata Roxb., Leptochloa chinensis (L.) Nees, Echinochloa crusgalli (L.) Beauv and Eclipta prostrata L., commonly found in rice–crayfish fields were evaluated using a quantitative feeding experiment and behaviour observation experiment. The results of the quantitative feeding and behaviour experiments were highly consistent. The P. clarkii gender and weed species had no interactive effects on survival rate, the daily feed intake (FI) and percentage of daily feed intake (PFI). The results of the quantitative feeding experiment showed that the FI and PFI values of both P. clarkii females and males were significantly higher in the P. clarkii feed group than in the weed treatment group. Both FI and PFI were significantly higher in the L. chinensis group than in the other treatment groups. The survival rate of P. clarkii was significantly lower in the E. crusgalli group than in the other treatment groups. The behaviour observation experiment showed that the feeding frequency and duration were in the order of L. chinensis > E. prostrata > L. prostrata > E. crusgalli. The results indicate that the P. clarkii specimens liked to eat L. chinensis (mean PFI was more than 2%), hardly fed on E. crusgalli.

Abstract Accumulating studies appear to suggest that the risk factors for venous thromboembolism (VTE) among young-middle-aged inpatients are different from those among elderly people. Therefore, the current prediction models for VTE are not applicable to young-middle-aged inpatients. The aim of this study was to develop and externally validate a new prediction model for young-middle-aged people using machine learning methods. The clinical data sets linked with 167 inpatients with deep venous thrombosis (DVT) and/or pulmonary embolism (PE) and 406 patients without DVT or PE were compared and analysed with machine learning techniques. Five algorithms, including logistic regression, decision tree, feed-forward neural network, support vector machine, and random forest, were used for training and preparing the models. The support vector machine model had the best performance, with AUC values of 0.806–0.944 for 95% CI, 59% sensitivity and 99% specificity, and an accuracy of 87%. Although different top predictors of adverse outcomes appeared in the different models, life-threatening illness, fibrinogen, RBCs, and PT appeared to be more consistently featured by the different models as top predictors of adverse outcomes. Clinical data sets of young and middle-aged inpatients can be used to accurately predict the risk of VTE with a support vector machine model.

Abstract This study investigated the ultrafiltration (UF) membrane fouling mechanism of intracellular organic matter (IOM) from Chlorella vulgaris (CV) and Microcystis aeruginosa (MA). Both CV- and MA-IOM caused severe membrane fouling during UF; however, there were significant differences in the membrane fouling by these two materials. Neutral hydrophilic (N-HPI) compounds were the organics that caused the most severe membrane fouling during CV-IOM filtration, whereas the MA-IOM membrane fouling was induced by mainly hydrophobic (HPO) organics. From an analysis based on Derjaguin–Landau–Verwey–Overbeek theory, it was found that the interaction energy between the membrane and foulants in the later stage of filtration was the major factor determining the efficiency of filtration for both CV-IOM and MA-IOM. The TPI organics in CV-IOM fouled the membrane to a more severe degree during the initial filtration flux; however, when the membrane surface was covered with CV-IOM foulants, the N-HPI fraction of CV-IOM caused the most severe membrane fouling because its attractive energy with the membrane was the highest. For MA-IOM, regardless of the initial filtration flux or the late stage of filtration, the HPO organics fouled the membrane to the greatest extent. An analysis of modified filtration models revealed that cake layer formation played a more important role than other fouling mechanisms during the filtration of CV-IOM and MA-IOM. This study provides a significant understanding of the membrane fouling mechanism of IOM and is beneficial for developing some strategies for membrane fouling control when treating MA and CV algae-laden waters.