Crystal structures of the 3C proteases from Coxsackievirus B3 and B4.

Enteroviruses cause a wide range of disorders with varying presentations and severities, and some enteroviruses have emerged as serious public health concerns. These include Coxsackievirus B3 (CVB3), an active causative agent of viral myocarditis, and Coxsackievirus B4 (CVB4), which may accelerate the progression of type 1 diabetes. The 3C proteases from CVB3 and CVB4 play important roles in the propagation of these viruses. In this study, the 3C proteases from CVB3 and CVB4 were expressed in Escherichia coli and purified by affinity chromatography and gel-filtration chromatography. The crystals of the CVB3 and CVB4 3C proteases diffracted to 2.10 and 2.01 Šresolution, respectively. The crystal structures were solved by the molecular-replacement method and contained a typical chymotrypsin-like fold and a conserved His40-Glu71-Cys147 catalytic triad. Comparison with the structures of 3C proteases from other enteroviruses revealed high similarity with minor differences, which will guide the design of 3C-targeting inhibitors with broad-spectrum properties.

The Effect of Paternal Co-Parenting on Preschool Children's Problem Behaviors: The Chain-Mediating Role of Maternal Parenting Burnout and Psychological Aggression.

Objective: With the social changes, a growing number of women have joined the workforce, leading to a shift in the traditional roles of child-rearing. There has been a growing focus on the significance of fathers' roles in child development, particularly the influence of fathers on children's problematic behaviors, making it an increasingly prominent issue. However, there is limited understanding regarding the potential mechanisms through which fathers may exert influence on children's problem behaviors. To address this gap, this study sought to investigate the link between paternal co-parenting and preschool children's problem behaviors, and the mediating effects of maternal parenting burnout and psychological aggression. Methods: This study used the Personal Information Form and four scales to administer questionnaires to 1164 mothers of preschool children (Mage = 4.26 ± 0.85) in Guangdong Province, China. The collected data underwent processing and analysis using SPSS 22.0. Results: Paternal co-parenting demonstrated a significantly positive correlation with problem behaviors among preschool children. The impact of paternal co-parenting on children's problem behaviors was mediated by maternal parenting burnout, maternal psychological aggression, and the combined effect of maternal parenting burnout and psychological aggression. Conclusion: Maternal parenting burnout and maternal psychological aggression play a sequential mediating role between paternal co-parenting and problem behaviors among preschool children. This study revealed the internal mechanism through which paternal co-parenting influenced problem behaviors exhibited by children. It provides some evidence to support the important role of fathers in child development, and provides a reference for policymakers and educators to develop interventions for children's problem behaviors.

Transformation of bisphenol AF by chlorination: kinetic study and product identification.

Bisphenol AF (BPAF), commonly used as a substitute for bisphenol A (BPA), is also an endocrine disruptor with cytotoxicity, neurotoxicity, genotoxicity, and biotoxicity. In this study, we found that BPAF could be effectively degraded by free chlorine. The second order rate constant of the reaction ranged from 1.67 to 126.67 M-1·s-1 in the pH range of 5.0-11.0. Nineteen products were detected by LC-Q-TOF-MS analysis, including chlorinated BPAF (i.e., mono/di/tri/tetrachloro-BPAF), 8 dimers, and 6 trimers. According to the identified products, two transformation pathways of electrophilic substitution and electron transfer are proposed. Humic acid (HA) could inhibit the degradation rate of BPAF due to its ability to reduce the reactive BPAF radical intermediates to the parent compound. The addition of low concentrations of Br- and I- accelerates the reaction rate of BPAF, due to the formation of HOBr and HOI with a higher oxidizing capacity. In seawater, BPAF degraded rapidly, and 16 new halogenated products were formed. Theoretical calculation shows that electrophilic substitution is more prone to occur at the ortho position of the hydroxyl group to form chlorinated products, while electron transfer tends to occur at the hydroxyl oxygen, resulting in the formation of BPAF radical and its subsequent coupling products.

Transformation of bromophenols by aqueous chlorination and exploration of main reaction mechanisms.

Bromophenols (BPs) are ubiquitous phenolic contaminants and typical halogenated disinfection byproducts (DBPs) that are commonly detected in aquatic environments. The transformation of 2,4-dibromophenol (2,4-DBP) during chlorination process was fully explored in this research. It was found that active chlorine can react with 2,4-DBP effectively in a wide pH range of 5.0-11.0, with an apparent second-order rate constant (kapp) varying from 0.8 M-1 s-1 to 110.3 M-1 s-1. The addition of 5 mM ammonium ions almost completely suppressed the reaction via competitive consumption of free chlorine. With the concentration of HA increasing from 1.0 to 10.0 mg L-1, the inhibition on the degradation of 2,4-DBP increased from 8.7% to 63.4%. By contrast, bromide ions at a concentration of 5 mM accelerated the process by about 4 times, due to the formation of hypobromous acid. On the basis of the eleven products (with eight nominal masses) identified by LC-TOF-MS, electrophilic substitution reactions and single-electron transfer reactions were mainly involved in the chlorination process. The concentration of primary chlorine-substituted products was about 4 times that of the dimer products, demonstrating that electrophilic substitution reaction was predominant during chlorination of 2,4-DBP. Density functional theory (DFT) based calculations revealed that HOCl is the dominant active oxidizing species for elimination of 2,4-DBP and coupling reaction occurs more easily at para and ortho position of hydroxyl group in the phenolic moiety. These findings could provide some new insights into the environmental fate of bromophenols during chlorine disinfection of water and wastewaters.

Transurethral balloon dilatation of the Prostate and Transurethral Plasmakinetic resection of the Prostate in the treatment of Prostatic Hyperplasia.

BACKGROUND & OBJECTIVE: With the aggravation of global aging, benign prostate hyperplasia tends to have a higher incidence and has been the most common disease in urinary surgery. It is usually treated by surgery. Our objective was to select an effective treatment scheme, the clinical efficacy and relevant indicators of transurethral balloon dilatation of the prostate (TUDP) and transurethral plasmakinetic resection of the prostate (PKRP) in the treatment of benign prostate hyperplasia were emphatically compared. METHODS: Ninety-eight patients with benign prostate hyperplasia who were admitted to the hospital of between May 2014 and July 2016 were selected and divided into a TUDP group (n=49) and PKRP (n=49) using random number table. The intraoperative blood loss, duration of surgery, international prostate symptom score (IPSS), quality of life (QOL), post-void residual urine (PVR) and complications of the two groups were observed. RESULTS: The results demonstrated that the postoperative blood loss and duration of surgery of the patients in the PKRP group were significantly higher than those of the TUDP group (P<0.05); the IPSS, QOL and PVR of the patients in the two groups after surgery were much lower than those before surgery (P<0.05); the IPSS, QOL and PVR of the patients in the PKRP group were significantly lower than those in the TUDP group after surgery (P<0.05). The incidence of postoperative complications of the PKRP group was 38.8%, which was apparently higher than 14.3% in the TUDP group (P<0.05). CONCLUSION: PKRP has better efficacy than TUDP in treating benign prostatic hyperplasia, but QOL was poor and there are many complications. Proper surgical procedure should be selected according to the specific disease condition of patients.

Development of the molecular methods for rapid detection and differentiation of Fusarium oxysporum and F. oxysporum f. sp. niveum in Taiwan.

Fusarium wilt, caused by Fusarium oxysporum (Fo), is one of the most important fungal diseases worldwide. Like other plant pathogens, Fo displays specialized forms in association with its hosts. For example, F. oxysporum f. sp. niveum (Fon) is the damaging pathogen causing Fusarium wilt disease on watermelon, whereas F. oxysporum f. sp. cubense is the pathogen that infects banana. A rapid and reliable pathogen identification or disease diagnosis is essential for the integrated disease management practices in many crops. In this study, two new primer sets, Fon-1/Fon-2 and FnSc-1/FnSc-2, were developed to differentiate Fon and Fo, respectively. The PCR method using the novel primer sets has high sensitivity to detect Fon when the DNA concentration was as low as 0.01 pg or when the conidia number was as few as 5. In comparison with the published primer set, the Fon-1/Fon-2 primer set, derived from the sequence of OP-M12 random primer-amplified fragment, produced a 174 bp DNA fragment, and was more specific to Fon in Taiwan. In addition, with optimized PCR parameters, the molecular method using the Fon-1/Fon-2 primer set could directly detect Fon even when watermelon samples were collected in its early stage of disease development.