Hierarchical TiO2–Ag/hydrogel coating used for outstanding antifouling detection of serotonin

Xiaoyan He,Shuo Ma,Nan Sun,Miaomiao Hou,Zheping Tan,Runze Cao 한국고분자학회 2024 Macromolecular Research Vol.32 No.6

Serotonin (5-HT) is an important neurotransmitter in vivo, regulating almost all human behavior and cognitive processes. Antifouling surface that can prevent undesirable adhesion is a key factor in the detection of 5-HT, hydrogels are considered as excellent candidates for non-fouling materials. It still remains a challenge to fabricate antifouling composites on electrode that can combine the properties of the hydrogels and surface morphology characteristics, at the same time, keeping good conductivity of the electrode. Herein, we report a new antifouling electrochemical biosensor for 5-HT detection. Using the photocatalytic activity of TiO2 and the conductivity of Ag nanoparticles, the antifouling layer of P(VPA-SBMA-GMA) hydrogel was formed by in situ polymerization on the surface of hierarchical nanoscale TiO2– Ag nanocomposite, 5-HT aptamers were further bound on the surface of the hydrogel for specific recognition. With these advantages, the constructed sensor had a wide detection range (0.5 pM–100 nM) and a lower detection limit (5 fM) for 5-HT.

Starch graft copolymer and polymer gel applied in Bohai oilfield for water plugging and profile control and their mechanisms

Weijia Cao,Kun Xie,Xiaoyan Wang,Xiangguo Lu,Xin He,Guorui Xu,Xiang Li 한국자원공학회 2020 Geosystem engineering Vol.23 No.4

Water plugging and profile control are becoming increasingly important in water-flooding oilfields. In this study, the experiments were conducted to determine the microscopic mechanisms and effects of water plugging, profile control, and ‘water plugging + profile control’. Initially, the starch graft copolymer and polymer gel used showed only slight changes in viscosity. However, within 12 h, the viscosities exceeded 100,000 mPa·s, which indicated that the two agents had good plugging effects. When the plugging agent was starch graft copolymer, the oil recovery with water plugging was 2% and 0.8% higher than the values for profile control with polymer gel on a heterogeneous core and parallel core, respectively. The recoveries with the ‘water plugging + profile control’ combination for the heterogeneous core and parallel core were 25.9% and 25.5%, respectively, which showed the superior enhanced oil recovery. The mechanism research showed that when the reservoir entered the middle and high water-cut development stages, the residual oil was mainly distributed in the middle- and low-permeability layers near the oil well. Thus, water plugging provided a greater increase in oil recovery. Under the actual demands of the Bohai oilfield, it would be better to adopt a combined water plugging and profile control operation.

Cantharidin Overcomes Imatinib Resistance by Depleting BCR-ABL in Chronic Myeloid Leukemia

Sun, Xiaoyan,Cai, Xueting,Yang, Jie,Chen, Jiao,Guo, Caixia,Cao, Peng Korean Society for Molecular and Cellular Biology 2016 Molecules and cells Vol.39 No.12

Cantharidin (CTD) is an active compound isolated from the traditional Chinese medicine blister beetle and displayed anticancer properties against various types of cancer cells. However, little is known about its effect on human chronic myeloid leukemia (CML) cells, including imatinib-resistant CML cells. The objective of this study was to investigate whether CTD could overcome imatinib resistance in imatinib-resistant CML cells and to explore the possible underlying mechanisms associated with the effect. Our results showed that CTD strongly inhibited the growth of both imatinib-sensitive and imatinib-resistant CML cells. CTD induced cell cycle arrest at mitotic phase and triggered DNA damage in CML cells. The ATM/ATR inhibitor CGK733 abrogated CTD-induced mitotic arrest but promoted the cytotoxic effects of CTD. In addition, we demonstrated that CTD downregulated the expression of the BCR-ABL protein and suppressed its downstream signal transduction. Real-time quantitative PCR revealed that CTD inhibited BCR-ABL at transcriptional level. Knockdown of BCR-ABL increased the cell-killing effects of CTD in K562 cells. These findings indicated that CTD overcomes imatinib resistance through depletion of BCR-ABL. Taken together, CTD is an important new candidate agent for CML therapy.

Transcriptome analysis of Dioscorea zingiberensis identifies genes involved in diosgenin biosynthesis

Wenping Hua,Weiwei Kong,XiaoYan Cao,Chen Chen,Qian Liu,Xiangmin Li,Zhezhi Wang 한국유전학회 2017 Genes & Genomics Vol.39 No.5

Dioscorea zingiberensis is the main plant source of diosgenin, a precursor for the production of steroid hormones used in the pharmaceutical industry. The extraction process of diosgenin from D. zingiberensis can generate high-acid and high-strength wastewater on a large scale and can threaten the environment. Bioengineering microorganisms to produce diosgenin is an effective way to avoid pollution. However, little is known about the genes that are involved in the biosynthesis of diosgenin. We obtained 85,010 unigenes (average length of 1142 bases) from the D. zingiberensis transcriptome through RNAseq. A large number of unigenes (59,368; 69.83%) were annotated, and 2488 unigenes were assigned to 27 secondary- metabolite pathways. In our database, 66 unigenes encoding up to 40 key enzymes were found to be present in diosgenin biosynthesis pathways. In addition, we found 203 unigenes encoding CYP450 proteins and 47 unigenes encoding UGT proteins that may be involved in modifications of a downstream pathway. The expression patterns of key diosgenin biosynthesis genes were studied to identify the most important members of the enzyme family. These results add to the available genetic data of D. zingiberensis and lay the foundation for the further production of diosgenin using genetic engineering.

Two-Dimensional Shear Wave Elastography Predicts Liver Fibrosis in Jaundiced Infants with Suspected Biliary Atresia: A Prospective Study

Chen Huadong,Zhou Luyao,Liao Bing,Cao Qinghua,Jiang Hong,Zhou Wenying,Wang Guotao,Xie Xiaoyan 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.6

Objective: This study aimed to evaluate the role of preoperative two-dimensional (2D) shear wave elastography (SWE) in assessing the stages of liver fibrosis in patients with suspected biliary atresia (BA) and compared its diagnostic performance with those of serum fibrosis biomarkers. Materials and Methods: This study was approved by the ethical committee, and written informed parental consent was obtained. Two hundred and sixteen patients were prospectively enrolled between January 2012 and October 2018. The 2D SWE measurements of 69 patients have been previously reported. 2D SWE measurements, serum fibrosis biomarkers, including fibrotic markers and biochemical test results, and liver histology parameters were obtained. 2D SWE values, serum biomarkers including, aspartate aminotransferase to platelet ratio index (APRi), and other serum fibrotic markers were correlated with the stages of liver fibrosis by METAVIR. Receiver operating characteristic (ROC) curves and area under the ROC (AUROC) curve analyses were used. Results: The correlation coefficient of 2D SWE value in correlation with the stages of liver fibrosis was 0.789 (p < 0.001). The cut-off values of 2D SWE were calculated as 9.1 kPa for F1, 11.6 kPa for F2, 13.0 kPa for F3, and 15.7 kPa for F4. The AUROCs of 2D SWE in the determination of the stages of liver fibrosis ranged from 0.869 to 0.941. The sensitivity and negative predictive value of 2D SWE in the diagnosis of ≥ F3 was 93.4% and 96.0%, respectively. The diagnostic performance of 2D SWE was superior to that of APRi and other serum fibrotic markers in predicting severe fibrosis and cirrhosis (all p < 0.005) and other serum biomarkers. Multivariate analysis showed that the 2D SWE value was the only statistically significant parameter for predicting liver fibrosis. Conclusion: 2D SWE is a more effective non-invasive tool for predicting the stage of liver fibrosis in patients with suspected BA, compared with serum fibrosis biomarkers.