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Background Acute bacterial meningitis (ABM) is a serious health issue in Yemen where civil war, which continues unabated, has crippled the healthcare system. We conducted a nationwide retrospective observational study in Yemeni sentinel hospitals to identify the prevalence, aetiology, vaccination coverage and spatio-temporal pattern of ABM in children aged <5 years before and during the civil war, 2014–20. Methods Cerebrospinal fluid samples were collected from hospitalized children and were analysed macroscopically for appearance and microscopically by Gram stain and white blood cell count. Culture and latex agglutination tests were performed. Data on the prevalence of and vaccination coverage for ABM were obtained from the Ministry of Health. Joinpoint regression was used to assess the annual percent change (APC) of ABM prevalence and vaccination coverage. Pearson's correlation was used to evaluate the association between ABM prevalence and vaccination coverage. Results In total, 11 339 hospitalized children had suspected cases of ABM (prevalence, 40.07/100 000 of the whole Yemeni population) and 2.6% (293/11 339) of suspected ABM cases were confirmed (prevalence, 1.04/100 000 of the whole Yemeni population). The dominant pathogens were Streptococcus pneumoniae , Neisseria meningitidis and Haemophilus influenzae type b (Hib). The civil war reduced the Hib and pneumococcal vaccination coverage (APC = –1.92), reaching its lowest (79.5%) in 2018. The prevalence of suspected ABM increased (APC = 3.46), reaching its maximum (6.08/100 000 of the whole Yemeni population) in 2019. The conflict inversely correlated with the ABM prevalence and vaccination coverage (Pearson correlation coefficient (r), –0.69 to –0.53). Ta'izz region, which was severely affected by the civil war, had the highest prevalence of suspected ABM (120.90/100 000 of the whole Yemeni population) and lowest vaccination coverage (60%). Conclusions The civil war had a negative impact on vaccination coverage and coincided with increasing prevalence of ABM in Yemen. Streptococcus pneumoniae is the dominant causative pathogen. [ABSTRACT FROM AUTHOR]

The calcium carbide slag and boron mud were used as raw materials to react with acetic acid to prepare acetate snow melting agent. The microstructure of the snow-melting agent was analyzed by XRD, TG and other methods. The pH, dissolution rate and relative snow-melting ability of the prepared snow-melting agent were tested to evaluate the snow-melting performance of the snow-melting agent. The results show that the acetate phase is mainly calcium acetate when calcium carbide slag is used as the raw material. The product is mixed acetate of calcium acetate and magnesium acetate after adding boron mud. The extraction rate decreased significantly, and the snow melting performance of the acetate product also decreased. When the calcium carbide slagu boron mud is 8u 2,the acetate snow melting agent prepared has high output efficiency, and the three technical indicators of disolution rate, pH and relative snow melting and ice melting ability conform to GB/T 23851-2017 Snow Melting Agents standard. [ABSTRACT FROM AUTHOR]

Enterovirus (EV) 71 caused episodes of outbreaks in China and Southeast Asia during the last few decades. We have previously reported that EV71 induces reactive oxygen species (ROS). However, the underlying mechanism remains elusive. Co-immunoprecipitation-proteomic analysis revealed that enteroviral 2B protein interacted with mitochondrial voltage-dependent anion channel 3 (VDAC3). Knockdown (KD) of VDAC3 expression specifically inhibited enteroviral replication. Single-round viral replication was also inhibited in KD cells, suggesting that VDAC3 plays an essential role in replication. Consistent with this, VDAC3 gene KD significantly reduced the EV71-induced mitochondrial ROS generation. Exogenous 2B expression could induce the mitochondrial ROS generation that was significantly reduced in VDAC3-KD cells or in the Mito-TEMPO-treated cells. Moreover, VDAC3 appears to be necessary for regulation of antioxidant metabolism. VDAC3 gene KD led to the enhancement of such pathways as hypotaurine/taurine synthesis in the infected cells. Taken together, these findings suggest that 2B and VDAC3 interact to enhance mitochondrial ROS generation, which promotes viral replication. [ABSTRACT FROM AUTHOR]

The experiment studied the screening of α -galactosidase producing strain of Aspergillus niger variants and optimization of fermentation conditions. After UV mutagenesis and subculture of Aspergillus niger strain MX-H, a strain MX-H1 with stable α-galactosidase production was obtained, and its medium for enzyme production was optimized. The 18S rDNA identification showed that strain MX-H1 was identified as Aspergillus niger. The results showed that the optimal conditions were carbon source 15 g/L sucrose, nitrogen source 10 g/L beef extract, the production inducer 0.5 g/L raffinose, the initial pH 6.0, the culture temperature 30 °C, the sample size 30 mL/250 mL and the shaking table 180 r/min for 96 h. Under the optimal conditions, the activity of α-galactosidase was 4.95 U/mL. The experiment provides a reference for industrial production of α-galactosidase. [ABSTRACT FROM AUTHOR]

The life cycle of leaves, from sprout to senescence, is the phenomenon of regular changes such as budding, branching, leaf spreading, flowering, fruiting, leaf fall, and dormancy due to seasonal climate changes. It is the effect of temperature and moisture in the life cycle on physiological changes, so the detection of newly grown leaves (NGL) is helpful for the estimation of tree growth and even climate change. This study focused on the detection of NGL based on deep learning convolutional neural network (CNN) models with sparse enhancement (SE). As the NGL areas found in forest images have similar sparse characteristics, we used a sparse image to enhance the signal of the NGL. The difference between the NGL and the background could be further improved. We then proposed hybrid CNN models that combined U-net and SegNet features to perform image segmentation. As the NGL in the image were relatively small and tiny targets, in terms of data characteristics, they also belonged to the problem of imbalanced data. Therefore, this paper further proposed 3-Layer SegNet, 3-Layer U-SegNet, 2-Layer U-SegNet, and 2-Layer Conv-U-SegNet architectures to reduce the pooling degree of traditional semantic segmentation models, and used a loss function to increase the weight of the NGL. According to the experimental results, our proposed algorithms were indeed helpful for the image segmentation of NGL and could achieve better kappa results by 0.743. [ABSTRACT FROM AUTHOR]

Enterovirus 71 (EV71) infection is an endemic disease in Southeast Asia and China. We have previously shown that EV71 virus causes functional changes in mitochondria. It is speculative whether EV71 virus alters the host cell metabolism to its own benefit. Using a metabolomics approach, we demonstrate that EV71-infected Vero cells had significant changes in metabolism. Glutathione and its related metabolites, and several amino acids, such as glutamate and aspartate, changed significantly with the infectious dose of virus. Other pathways, including glycolysis and tricarboxylic acid cycle, were also altered. A change in glutamine/glutamate metabolism is critical to the viral infection. The presence of glutamine in culture medium was associated with an increase in viral replication. Dimethyl α-ketoglutarate treatment partially mimicked the effect of glutamine supplementation. In addition, the immunoblot analysis revealed that the expression of glutamate dehydrogenase (GDH) and trifunctional carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase (CAD) increased during infection. Knockdown of expression of glutaminase (GLS), GDH and CAD drastically reduced the cytopathic effect (CPE) and viral replication. Furthermore, we found that CAD bound VP1 to promote the de novo pyrimidine synthesis. Our findings suggest that virus may induce metabolic reprogramming of host cells to promote its replication through interactions between viral and host cell proteins. [ABSTRACT FROM AUTHOR]