Limonoids from the roots of Trichilia sinensis and their cytotoxicities

Zhu-Nian Wang,Wen-Li Mei,Hui-Qin Chen,Jun Wang,Zhu-Nian Wang,Hao Fu Dai 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.12

Six new compounds (1–4, 8, 10), along with six known limonoids (5–7, 9, 11, 12), were isolated from the roots of Trichilia sinensis. Their structures were elucidated on the basis of extensive spectroscopic methods including 1H NMR, 13C NMR, DEPT, HSQC, HMBC, 1H–1H COSY and ROESY experiments, as well as by comparison with the literature. All the compounds were evaluated for cytotoxicities against K562, SGC-7901 and BEL-7402 cell lines. Compounds 2, 7, 10, 11, and 12 showed weak inhibitory activity to the selected cell lines.

Ischemic postconditioning protects cardiomyocytes against ischemia/reperfusion injury by inducing MIP2

Zhu, Hong-Lin,Wei, Xing,Qu, Shun-Lin,Zhang, Chi,Zuo, Xiao-Xia,Feng, Yan-Sheng,Luo, Qi,Chen, Guang-Wen,Liu, Mei-Dong,Jiang, Lei,Xiao, Xian-Zhong,Wang, Kang-Kai Korean Society for Biochemistry and Molecular Bion 2011 Experimental and molecular medicine Vol.43 No.8

Cardiomyocytes can resist ischemia/reperfusion(I/R) injury through ischemic postconditioning (IPoC) which is repetitive ischemia induced during the onset of reperfusion. Myocardial ischemic preconditioning up-regulated protein 2 (MIP2) is a member of the WD-40 family proteins, we previously showed that MIP2 was up-regulated during ischemic preconditioning (IPC). As IPC and IPoC engaged similar molecular mechanisms in cardioprotection, this study aimed to elucidate whether MIP2 was up-regulated during IPoC and contributed to IPoC-mediated protection against I/R injury. The experiment was conducted on two models, an $in$ $vivo$ open chest rat coronary artery occlusion model and an $in$ $vitro$ model with H9c2 myogenic cells. In both models, 3 groups were constituted and randomly designated as the sham, I/R and IPoC/hypoxia postconditioning (HPoC) groups. In the IPoC group, after 45 min of ischemia, hearts were allowed three cycles of reperfusion/ischemia phases (each of 30 s duration) followed by reperfusion. In the HPoC group, after 6 h of hypoxia, H9c2 cells were subjected to three cycles of 10 minute reoxygenation and 10 minute hypoxia followed by reoxygenation. IPoC significantly reduced the infarct size, plasma level of Lactate dehydrogenase and creatine kinase MB in rats. 12 h after the reperfusion, MIP2 mRNA levels in the IPoC group were 10 folds that of the sham group and 1.4 folds that of the I/R group. Increased expression of MIP2 mRNA and attenuation of apoptosis were similarly observed in the HPoC group in the $in$ $vitro$ model. These effects were blunted by transfection with MIP2 siRNA in the H9c2 cells. This study demonstrated that IPoC induced protection was associated with increased expression of MIP2. Both MIP2 overexpression and MIP2 suppression can influence the IPoC induced protection.

Atom Transfer Radical Polymerization of Hexadecyl Acrylate Using CuSCN as the Catalyst

Wen Jian Xu,Xiu Lin Zhu,Zhen Ping Cheng,Jian Ying Chen,Jian Mei Lu 한국고분자학회 2004 Macromolecular Research Vol.12 No.1

Selection and optimization of nutritional risk screening tools for esophageal cancer patients in China

Wen Dong,Xiguang Liu,Shunfang Zhu,Di Lu,Kaican Cai,Ruijun Cai,Qing Li,Jingjing Zeng,Mei Li 한국영양학회 2020 Nutrition Research and Practice Vol.14 No.1

BACKGROUND/OBJECTIVES: Malnutrition has multiple impacts on surgical success, postoperative complications, duration of hospital stay, and costs, particularly for cancer patients. There are various nutrition risk screening tools available for clinical use. Herein, we aim to determine the most appropriate nutritional risk screening system for esophageal cancer (EC) patients in China. SUBJECTS/METHODS: In total, 138 EC patients were enrolled in this study and evaluated by experienced nurses using three different nutritional screening tools, the Nutrition Risk Screening 2002 tool (NRS2002), the Patient-generated Subjective Globe Assessment (PG-SGA), and the Nutrition Risk Index (NRI).We compared sensitivity, specificity, positive and negative likelihood ratios, and Youden index generated by each of the three screening tools. Finally, cut-off points for all three tools were re-defined to optimize and validate the best nutritional risk screening tool for assessing EC patients. RESULTS: Our data suggested that all three screening tools were 100% sensitive for EC patients, while the specificities were 44.4%, 2.96%, and 59.26% for NRS 2002, PG-SGA, and NRI, respectively. NRI had a higher positive likelihood ratio as well as a higher area under the receiver operating characteristic curve compared to those of NRS 2002 and PG-SGA; although, all three tools had null negative likelihood ratios. After adjusting the cut-off points, the specificity and accuracy for all tools were significantly improved, however, the NRI remained the most appropriate nutritional risk screening system for EC patients. CONCLUSIONS: The NRI is the most suitable (highest sensitivity and accuracy) nutritional risk screening tool for EC patients. The performance of the NRI can be significantly improved if the cut-off point is modified according to the results obtained using MedCalc software.

Novel method for equivalent stiffness and Coulomb’s damping ratio analyses of leaf spring

Wu Wen-jun,Zhu Le-mei,Xiang Yu,He Li-jun 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.11

The leaf spring is a representative type of laminated structure. Based on the linear theories of curve beams, the first derivatives of the leave’s status-vector of the leaf spring are provided. The first derivatives of the combination status-vector are obtained by properly dealing with the nonlinear interacted forces between adjacent leaves. Moreover, the precise integration technology and the transform matrix method are introduced to solve the equations. The force-displacement curve of a leaf spring is then calculated separately by using the present method and the finite element software ANSYS. From the results, the precision and advantages of the present methods for analyzing the leaf spring are revealed. The Coulomb’s damping ratio of the leaf spring is studied by using the present method.

Ischemic postconditioning protects cardiomyocytes against ischemia/reperfusion injury by inducing MIP2

Hong-Lin Zhu,Kang-Kai Wang,Xing Wei,Shun-Lin Qu,Chi Zhang,Xiao-Xia Zuo,Yan-Sheng Feng,Qi Luo,Guang-Wen Chen,Mei-Dong Liu,Lei Jiang,Xian-Zhong Xiao 생화학분자생물학회 2011 Experimental and molecular medicine Vol.43 No.8

Cardiomyocytes can resist ischemia/reperfusion (I/R)injury through ischemic postconditioning (IPoC)which is repetitive ischemia induced during the onset of reperfusion. Myocardial ischemic preconditioning up-regulated protein 2 (MIP2) is a member of the WD-40family proteins, we previously showed that MIP2 was up-regulated during ischemic preconditioning (IPC). As IPC and IPoC engaged similar molecular mechanisms in cardioprotection, this study aimed to elucidate whether MIP2 was up-regulated during IPoC and contributed to IPoC-mediated protection against I/R injury. The experiment was conducted on two models,an in vivo open chest rat coronary artery occlusion model and an in vitro model with H9c2 myogenic cells. In both models, 3 groups were constituted and randomly designated as the sham, I/R and IPoC/hypoxia postconditioning (HPoC) groups. In the IPoC group, after 45 min of ischemia, hearts were allowed three cycles of reperfusion/ischemia phases (each of 30 s duration)followed by reperfusion. In the HPoC group, after 6 h of hypoxia, H9c2 cells were subjected to three cycles of 10 minute reoxygenation and 10 minute hypoxia followed by reoxygenation. IPoC significantly reduced the infarct size, plasma level of Lactate dehydrogenase and creatine kinase MB in rats. 12 h after the reperfusion,MIP2 mRNA levels in the IPoC group were 10 folds that of the sham group and 1.4 folds that of the I/R group. Increased expression of MIP2 mRNA and attenuation of apoptosis were similarly observed in the HPoC group in the in vitro model. These effects were blunted by transfection with MIP2 siRNA in the H9c2cells. This study demonstrated that IPoC induced protection was associated with increased expression of MIP2. Both MIP2 overexpression and MIP2 suppression can influence the IPoC induced protection.

Processing Errors in an On-Machine Measurement Method Based on the Adaptive Triangular Mesh

Wu Shi,Mei-wen Zhu,Xian-li Liu,Li-jian Bian,Yang Lin 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.5

A novel, on-machine method applying the adaptive triangular mesh sampling measuring process on automotive parts mold was elaborated in order to obtain the processing errors of free-form surfaces. This process has firstly generated a triangular mesh through the advancing front method. This has allowed us to extract the coordinate data corresponding to the mesh nodes. Subsequently, the processed surfaces were fitted by the mean of NURBS surface reconstruction. The final stage has employed the determination of the normal distance between the reconstructed and theoretical surfaces using the generalized Newtonian method, which has eventually allowed us to obtain the free-form surface machining errors as well as the model surface profile errors corresponding to the experimental process. Therefore, we have effectively determined the free-form surface processing errors by using the processing surface reconstruction methodology based on the adaptive triangular mesh sampling.

Genome-wide analysis of codon usage bias patterns in an enterotoxigenic Escherichia coli F18 strain

Ri Wei Xia,Wen Bin Bao,Xue Mei Yin,Wei Yun Qin,Guo Qiang Zhu,Sheng Long Wu 한국유전학회 2017 Genes & Genomics Vol.39 No.11

Enterogenic Escherichia coli (ETEC) F18 strains are the main pathogenic bacteria causing severe diarrhea in humans and domestic animals. However, the information about synonymous codon usage pattern of ETEC F18 genome remains unclear. We conducted a genome-wide analysis of synonymous codon usage patterns in the ETEC F18 strain SRA: SAMN02471895. After filtering of the complete genome sequence, 4327 coding sequences were analyzed using multivariate statistical methods to calculate synonymous codon usage patterns and to evaluate the influence of various factors in shaping the codon usage. The mean GC content was 51.38%, with a slight preference for G/C-ending codons. Twenty-two codons were determined as ‘‘optimal codons”. ENC plots showed some of the genes were on or close to the expected curve, while only points with low-ENC values were below the curve. PR2 analysis showed that GC and AT were not used proportionally, suggesting major roles for mutational pressure and natural selection in shaping usage. Neutrality plots showed a significant correlation between GC12 and GC3, suggesting that mutational pressure is responsible for nucleotide composition in shaping the strength of codon usage. Translational selection was the main factor shaping the codon usage pattern of ETEC F18 genome, while other factors such as protein length, GRAVY and ARO values also influenced codon usage to some extent. We analyzed the codon usage pattern systematically and identified the factors shaping codon usage bias in the ETEC F18 genome. Such information further elucidates the mechanisms of synonymous codon usage bias and provides the basis of molecular genetic engineering and evolutionary studies.

RNA silencing-mediated resistance is related to biotic/abiotic stresses and cellular RdRp expression in transgenic tobacco plants

( Xiao Liang Wu ),( Wen Cui Hou ),( Mei Mei Wang ),( Xiao Ping Zhu ),( Fang Li ),( Jie Dao Zhang ),( Xin Zheng Li ),( Xing Qi Guo ) 생화학분자생물학회 2008 BMB Reports Vol.41 No.5

Genetic Overlap in the Quantitative Resistance of Rice at the Seedling and Adult Stages to Xanthomonas oryzae pv. oryzae

Yong-Li Zhou,Xue-Wen Xie,Mei-Rong Xu,Jin-Ping Zang,Ling-Hua Zhu,Jian-Long Xu,Zhi-Kang Li 한국식물학회 2012 Journal of Plant Biology Vol.55 No.2

The genetic components responsible for the qualitative and quantitative resistance of rice to three Chinese races (C2, C4, and C5) of Xanthomonas oryzae pv. oryzae (Xoo)were investigated at the seedling and adult stages in two successive years in set of Lemont/Teqing cross introgression lines (ILs) in a Teqing background, to create a complete linkage map using 160 well-distributed SSR markers. Teqing was resistant to C2 and C4, but moderately susceptible to C5,whereas Lemont was susceptible to all three races. Highly significant correlations were detected among the resistance to different races at different developmental stages. A major gene (Xa4), 14 main-effect QTLs (M-QTLs), and 18 epistatic QTLs were identified in the two developmental stages over 2 years,and were largely responsible for the segregation of resistance in the ILs. In 2007, the Lemont alleles at all loci in the seedling stage, except QBbr10 to C4, increased lesion length (LL) or decreased resistance. The Teqing allele at the Xa4 locus acted as a resistance gene against C2 and C4, but acted as a M-QTL when its resistance was overcome by the virulent race C5. MQTLs showed a degree of race specificity and had a cumulative effect on resistance. Most M-QTLs (94%) consistently expressed resistance to the same race at the seedling and adult stages, indicating that a high degree of genetic overlap exists between Xoo resistance at both developmental stages in rice. Among the digenic interactions, most co-introgressed Lemont alleles at the two epistatic loci lead to significantly smaller LL with all three races, compared to other types of interacting alleles at both development stages. The results indicate that a high level of resistance may be achieved by the cumulative effect of multiple M-QTLs, including the residual effects of “defeated” major resistance genes and the epistatic effects of co-introgression from diverse susceptible varieties.