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Kaempferol and quercetin possess various biological activities, making them valuable in food and medicine. However, their production via traditional methods is often inefficient. This study aims to address this gap by engineering the yeast Yarrowia lipolytica to achieve high yields of these flavonoids. We designed a kaempferol biosynthetic pathway by integrating multiple-copy fusion enzyme expression modules, F3H-(GGGGS)2-FLS, into the genome with an optimized linker (GGGGS)2 to enhance kaempferol production from naringenin. To synthesize quercetin de novo, we introduced the FMOCPR gene into the kaempferol-synthesizing strain using the optimized pFBAin promoter. Notably, increasing glucose concentration effectively boosted the production of both flavonoids. Our results demonstrated kaempferol and quercetin titers reaching 194.30 ± 7.69 and 278.92 ± 11.58 mg/L, respectively, in shake-flask cultures. These findings suggest that Y. lipolytica is a promising platform for the efficient production of flavonoid-derived products. [ABSTRACT FROM AUTHOR]

Objective To use in vitro experiments to verify the changes of proliferation, senescence and apoptosis of hepatocellular carcinoma cells after inhibiting the expression of NEK7, and to explore the related molecular mechanism. Methods Western blot and RT-PCR were used to detect the expression of NEK7 in hepatocellular carcinoma cells and THLE-2 cells. A viral vector was designed to inhibit the expression of NEK7 based on the gene sequence. After hepatocellular carcinoma cells were transfected, we observed the changes of proliferation activity, cell senescence, cell apoptosis and cell cycle in vitro. Western blot was used to detect the expression of cell cycle-related factors. Results Compared with THLE-2 cells, NEK7 was highly expressed in hepatocellular carcinoma cells. After inhibiting the expression of NEK7 with shRNA, the proliferation of hepatocellular carcinoma cells was inhibited, the proportions of cell senescence and apoptosis were increased, meanwhile, the cell number in stage S and G2/M was significantly reduced, the cell cycle progression was blocked, the expression levels of C-myc, c-Fos, cyclin D1 and cyclin E were inhibited, P16 and P27 expression were increased, and CDK2, CDK4 and CDK6 expression were not significantly changed. Conclusion After inhibiting the expression of NEK7, the proliferation ability of hepatocellular carcinoma cells is reduced, cell senescence is promoted and apoptosis is induced; meanwhile, the cell cycle progress is blocked.

Objective: The prevalence of childhood asthma has been increasing in recent years. This study aims to investigate the involvement of the key molecules of IL‐1 (interleukin‐1) signaling pathways in pediatric patients with asthma. Methods: Differentially expressed genes (DEGs) associated with IL‐1 signaling pathways were identified with RNA‐seq from peripheral blood samples collected from asthmatic or healthy children and were further verified in clinical peripheral blood samples. Cellular models and asthmatic mice were subsequently developed to validate the identified asthmatic markers. Results: Among the DEGs identified by RNA‐seq, eight signal transducers associated with the IL‐1 signaling network, namely IL‐1RN, IL‐1β, IL‐1RAP, IRAK3, IL‐1R1, MYD88, IRAK2, and PELI1, were found to be substantially upregulated in children with asthma. Interestingly, a significant serially increased expression of four genes (IL‐1RN, IL‐1RAP, IRAK3, and PELI1) was observed in healthy subjects, patients with chronic persistent asthma and patients with acute exacerbation asthma. In particular, these four genes were continuously overexpressed in recurrent patients. A significant induction of the above four genes was then observed in house dust mite (HDM)–stimulated peripheral blood mononuclear cells (PBMCs) and ovalbumin (OVA)–induced asthmatic mice. In addition, a time‐dependent induction of IL‐1RAP and PELI1 was also detected in HDM‐treated THP‐1 cells, an acute monocytic leukemia cell line. Conclusions: These results demonstrate that IL‐1RN, IL‐1RAP, IRAK3, and PELI1, which are signal transducers of the IL‐1 signaling pathway, could serve as biomarkers for the pathogenesis of childhood asthma and for potential therapeutic targets of asthma. [ABSTRACT FROM AUTHOR]

Previous studies have reported that T cell immunoglobulin domain and mucin domain-3 (TIM-3) 574T>G and 1516G>T are associated with the risk of asthma. However, the results are inconsistent due to the small sample size and varied age in studies. We performed this meta-analysis to systematically evaluated the effect of TIM-3 574T>G and 1516G>T genetic polymorphisms on asthma. Eligible articles that reported an association between TIM-3 574T>G and 1516G>T genetic polymorphisms and asthma were searched in PubMed, Medline, EMBASE, Google Scholar, and China National Knowledge Infrastructure up to April 2020. Random or fixed-effects models were used to calculate the summary of odds ratios (ORs) and 95% confidence intervals (CIs) to detect any potential associations between TIM-3 genetic polymorphisms and asthma. Subgroup and sensitivity analyses were performed to assess the potential sources of heterogeneity and the robustness of the pooled estimation. Publication bias was analyzed using the Egger test. A total of 11 case-control studies including 2077 asthma patients and 2122 control subjects were finally analyzed (published data form 2004-2018). The pooled results indicated that TIM-3 574T>G genetic polymorphisms were significantly associated with an increased risk of asthma under the dominant model (GG vs. GT +TT: ORs=2.26, 95% CI 1.09-4.69) and allele model (G vs T: ORs=2.60, 95% CI 1.20-5.64). However, no significant associations between TIM-3 1516G>T genetic polymorphisms with asthma in any model was found. No evidence of publication bias was observed.  Our study indicates that TIM-3 574T>G genetic polymorphisms were associated with increased risk of asthma and the TIM-3 1516G>T genetic polymorphisms may not be correlated with asthma. [ABSTRACT FROM AUTHOR]

Background: MRI signal diffusion-weighted imaging (DWI) hyperintensity in the hippocampus in patients with transient global amnesia (TGA) are resolved within several days after the onset of TGA.Purpose: To use multiparametric MRI to unravel the sequelae of TGA.Study Type: A prospective longitudinal study.Population: Eight TGA patients.Field Strength/sequence: A 3.0T Siemens Tim Trio MRI scanner with T1 -weighted MPRAGE, diffusion-weighted echo planar imaging, and multiecho gradient-recalled echo sequences.Assessment: Brain MRI scanned within 72 hours, 2 weeks, and 3 months after onset of TGA, respectively. T1 image hippocampus was first segmented into 12 subregions using FreeSurfer and registered to DWI to locate DWI lesion. Then a T1 image with segmented hippocampus was registered to its corresponding apparent diffusion coefficient (ADC) map, fractional anisotropy (FA) map, and quantitative susceptibility map, respectively. Finally, the volume, water diffusion and anisotropy, and magnetic susceptibility of DWI lesion were analyzed.Statistical Tests: A paired samples t-test was performed to detect measurement differences between three tests. Pearson correlation was used to assess the correlations between all measurements.Results: Hyperintensity was detected in the head, body, and caudate of CA1 and hippocampal tail. No significant changes existed in CA1/unit volume across the three timepoint measurements (all, P > 0.480). In Test 1, ratio ADC (DWI lesion / adjacent healthy, rADC) and ratio FA (rFA) decreased below, while ratio susceptibility increased above 1.0. In Test 2, all the episodes normalized around 1.0. In Test 3, rADC remained normalization, but rFA decreased and ratio susceptibility increased again. In Test 1 and Test 3 (vs. Test 2), decreased FA values were accompanied with lower axial diffusivity and/or higher radial diffusivity (all, P < 0.001). Moreover, rFA significantly correlated with ratio susceptibility in Test 3 (r = -0.665, P = 0.039).Data Conclusion: Microstructural sequelae in hippocampus were demonstrated, which indicates that ischemic lesions may be associated with TGA.Level Of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1350-1358. [ABSTRACT FROM AUTHOR]

Methane is the second most significant greenhouse gas. Landfill cover soils play an important role in mitigation of methane emission from critical sources – Landfills. In this study, methane removal biocover materials based on cattle manure compost (CMC) were constructed and its performance was investigated. When comparing CH4removal abilities of sand (S), clay soil (CS), paddy soil (PS) and CMC, CMC was the most effective biocover material for the reduction of methane emission. The maximum removal rate (Vmax) and half saturation constant (Km) of CMC peaked at 3451.25 ± 18.57 μg g−1 h−1and 3.67 ± 0.02 × 105 ppm, respectively, which are higher than those in previous studies. Thereafter, three compounded biocover materials (CBMs) were established based on the mixture of CMC and other three materials (ratio of 2:8). The rate of the three CBMs was enhanced by 13.56, 13.27 and 16.42 times, respectively, more than the S, CS and PS by adding CMC. Saturated water content of 80% and 35°C were found to be the optimum moisture and temperature, respectively, for CBMs. Analysis of community diversity using terminal restriction fragment length polymorphism (T-RFLP) showed that the diversity and evenness indexes of the CBMs decreased after adding CMC; Type I methanotroph was the most dominated methanotroph in the CBMs. CMC not only influenced bacterial community but also improved nutrient and CH4removal capacity of CBMs. All results showed that CMC and CBMs could effectively remove CH4, and the screening and construction of CBMs are important for decreasing CH4emission. [ABSTRACT FROM AUTHOR]