Multiparametric mri-based radiomics nomogram for predicting lymph-vascular space invasion in cervical cancer.

PURPOSE: To develop and validate a multiparametric magnetic resonance imaging (mpMRI)-based radiomics model for predicting lymph-vascular space invasion (LVSI) of cervical cancer (CC). METHODS: The data of 177 CC patients were retrospectively collected and randomly divided into the training cohort (n=123) and testing cohort (n = 54). All patients received preoperative MRI. Feature selection and radiomics model construction were performed using max-relevance and min-redundancy (mRMR) and the least absolute shrinkage and selection operator (LASSO) on the training cohort. The models were established based on the extracted features. The optimal model was selected and combined with clinical independent risk factors to establish the radiomics fusion model and the nomogram. The diagnostic performance of the model was assessed by the area under the curve. RESULTS: Feature selection extracted the thirteen most important features for model construction. These radiomics features and one clinical characteristic were selected showed favorable discrimination between LVSI and non-LVSI groups. The AUCs of the radiomics nomogram and the mpMRI radiomics model were 0.838 and 0.835 in the training cohort, and 0.837 and 0.817 in the testing cohort. CONCLUSION: The nomogram model based on mpMRI radiomics has high diagnostic performance for preoperative prediction of LVSI in patients with CC.

Organoelectrophotocatalytic C-H Silylation of Heteroarenes.

An organoelectrophotocatalytic approach for the C-H silylation of heteroarenes through dehydrogenation cross-coupling with H2 evolution has been developed. The organoelectrophotocatalytic strategy is carried out under a simple and efficient monocatalytic system by employing 9,10-phenanthrenequinone both as an organocatalyst and as a hydrogen atom transfer (HAT) reagent, which avoids the need for an external HAT reagent, an oxidant, or a metal reagent. A variety of heteroarenes can be compatible in satisfactory yields with excellent regioselectivity.

[Effects of Different Types of Plastic Film Mulching on Soil Quality, Root Growth, and Yield].

Aiming to address the problem of soil environmental pollution caused by the large-scale use of plastic film in agricultural production in China, field experiments were carried out by applying degradable plastic film. Pumpkin was used as the research material to explore the effects of black common plastic film (CK), white degradation plastic film (WDF), black degradation plastic film (BDF), and black CO2-based degradable plastic film (C-DF) on soil physicochemical properties, root growth and yield, and soil quality. The results showed that the soil water content and temperature of the three degradable plastic films were lower than those of ordinary plastic films to different degrees; there was no significant difference in soil organic matter content among the treatments. The soil available potassium content of the C-DF treatment was lower than that of CK, and WDF and BDF had no significant effect. Compared with those in CK and WDF, soil total nitrogen and available nitrogen contents in the BDF and C-DF treatments were lower, and the difference between treatments reached a significant level. Compared with that of CK, the catalase activities of the three types of degradation membranes were significantly increased by 2.9%-6.8%, and the sucrase was significantly decreased by 33.3%-38.4%. Compared with that in CK, the soil cellulase activity in the BDF treatment was significantly increased by 63.8%, whereas WDF and C-DF had no significant effects. The three types of degradable film treatments could promote the growth of underground roots, and the growth vigor was obviously enhanced. The yield of pumpkin treated with BDF and C-DF was close to that of CK, and the yield of pumpkin treated with BDF was significantly lower than that of CK by 11.4%. The experimental results showed that the effects of the BDF and C-DF treatments on soil quality and yield were comparable to those of CK. According to the results, two types of black degradable plastic film can effectively replace ordinary plastic film in the high-temperature production season.

De novo synthesis of nervonic acid and optimization of metabolic regulation by Yarrowia lipolytica.

Nervonic acid, a natural fatty acid compound and also a core component of nerve fibers and nerve cells, has been widely used to prevent and treat related diseases of the brain nervous system. At present, fatty acids and their derivatives are mainly obtained by natural extraction or chemical synthesis which are limited by natural resources and production costs. In this study, the de novo synthetic pathway of nervonic acid was constructed in Yarrowia lipolytica by means of synthetic biology, and the yield of nervonic acid was further improved by metabolic engineering and fermentation optimization. Specially, heterologous elongases and desaturases derived from different organism were successfully expressed and evaluated for their potential for the production of nervonic acid in Y. lipolytica. Meanwhile, we overexpressed the genes involved in the lipid metabolism to increase the nervonic acid titer to 111.6 mg/L. In addition, the potential of adding oil as auxiliary carbon sources for nervonic acid production by the engineered Y. lipolytica was analyzed. The results indicated that supplementation with colleseed oil as an auxiliary carbon source can be beneficial for the nervonic acid productivity, which led to the highest concentration of 185.0 mg/L in this work. To summarize, this study describes that the Y. lipolytica can be used as a promising platform for the production of nervonic acid and other very long-chain fatty acids.

Yarrowia lipolytica as a Metabolic Engineering Platform for the Production of Very-Long-Chain Wax Esters.

The oleaginous yeast Yarrowia lipolytica is an attractive cell factory platform strain and can be used for sustainable production of high-value oleochemical products. Wax esters (WEs) have a good lubricating property and are usually used as a base for the production of advanced lubricants and emollient oils. In this study, we reported the metabolic engineering of Y. lipolytica to heterologously biosynthesize high-content very-long-chain fatty acids (VLCFAs) and fatty alcohols and efficiently esterify them to obtain very-long-chain WEs. Co-expression of fatty acid elongases from different sources in Y. lipolytica could yield VLCFAs with carbon chain lengths up to 24. Combining with optimization of the central metabolic modules could further enhance the biosynthesis of VLCFAs. Furthermore, through the screening of heterologous fatty acyl reductases (FARs), we enabled high-level production of fatty alcohols. Genomic integration and heterologous expression of wax synthase (WS) and FAR in a VLCFA-producing Y. lipolytica strain yielded 95-650 mg/L WEs with carbon chain lengths from 32 to 44. Scaled-up fermentation in 5 L laboratory bioreactors significantly increased the production of WEs to 2.0 g/L, the highest content so far in yeasts. This study contributes to the further efficient biosynthesis of VLCFAs and their derivatives.

[Environmental geochemical baseline of heavy metals in soils of the Ili river basin and pollution evaluation].

Environmental geochemical baseline models of Cu, Zn, Pb, As, Hg were established by standardized method in the ehernozem, chestnut soil, sierozem and saline soil from the Ili river valley region. The theoretical baseline values were calculated. Baseline factor pollution index evaluation method, environmental background value evaluation method and heavy metal cleanliness evaluation method were used to compare soil pollution degrees. The baseline factor pollution index evaluation showed that As pollution was the most prominent among the four typical types of soils within the river basin, with 7.14%, 9.76%, 7.50% of sampling points in chernozem, chestnut soil and sierozem reached the heavy pollution, respectively. 7.32% of sampling points of chestnut soil reached the permitted heavy metal Pb pollution index in the chestnut soil. The variation extent of As and Pb was the largest, indicating large human disturbance. Environmental background value evaluation showed that As was the main pollution element, followed by Cu, Zn and Pb. Heavy metal cleanliness evaluation showed that Cu, Zn and Pb were better than cleanliness level 2 and Hg was the of cleanliness level 1 in all four types of soils. As showed moderate pollution in sierozem, and it was of cleanliness level 2 or better in chernozem, chestnut soil and saline-alkali soil. Comparing the three evaluation systems, the baseline factor pollution index evaluation more comprehensively reflected the geochemical migration characteristics of elements and the soil formation processes, and the pollution assessment could be specific to the sampling points. The environmental background value evaluation neglected the natural migration of heavy metals and the deposition process in the soil since it was established on the regional background values. The main purpose of the heavy metal cleanliness evaluation was to evaluate the safety degree of soil environment.