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      • KCI등재

        Synthesis and Biological Evaluation of Heterocyclic Ring-substituted Chalcone Derivatives as Novel Inhibitors of Protein Tyrosine Phosphatase 1B

        Zhen-Hua Chen,Liang-Peng Sun,Wei Zhang,Qiang Shen,Li-Xin Gao,Jia Li,Hu-Ri Piao 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.5

        Protein tyrosine phosphatase 1B (PTP1B) is a key factor in negative regulation of the insulin pathway, and is a promising target for the treatment of type-II diabetes, obesity and cancer. Herein, compound (4) was first observed to have moderate inhibitory activity against PTP1B with an IC50 value of 13.72 ± 1.53 μM. To obtain more potent PTP1B inhibitors, we synthesized a series of chalcone derivatives using compound (4) as the lead compound. Compound 4l (IC50 = 3.12 ± 0.18 μM) was 4.4-fold more potent than the lead compound 4 (IC50 = 13.72 ± 1.53 μM), and more potent than the positive control, ursolic acid (IC50 = 3.40 ± 0.21 μM). These results may help to provide suitable drug-like lead compounds for the design of inhibitors of PTP1B as well as other PTPs.

      • KCI등재

        Factors affecting the properties of recycled concrete by using neural networks

        Zhen-Hua Duan,Chi-Sun Poon 사단법인 한국계산역학회 2014 Computers and Concrete, An International Journal Vol.14 No.5

        Artificial neural networks (ANN) has been proven to be able to predict the compressive strength and elastic modulus of recycled aggregate concrete (RAC) made with recycled aggregates (RAs) from different sources. However, ANN is itself like a black box and the output from the model cannot generate an exact mathematical model that can be used for detailed analysis. So in this study, sensitivity analysis is conducted to further examine the influence of each selected factor on the output value of the models. This is not only conducive to the determination and selection of the more important factors affecting the results, but also can provide guidance for researchers in adjusting mix proportions appropriately when designing RAC based on the variation of these factors.

      • KCI등재

        Phosphoric Acid Modified Nb2O5: A Selective and Reusable Catalyst for Dehydration of Sorbitol to Isosorbide

        Zhen-Chen Tang,Ding-Hua Yu,Peng Sun,Heng Li,He Huang 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.12

        Niobium oxide (Nb2O5) and phosphated Nb2O5 were synthesized and used as catalysts for sorbitol dehydration to isosorbide. The characterization results of N2 adsorption, XRD and NH3-TPD revealed that the phosphoric acid modification could well prevent the crystallization of Nb2O5. And the amorphous phosphated Nb2O5 catalysts kept the relatively large surface area and stable acidity at high calcination temperature. The catalytic results showed that the selectivity to isosorbide could be dramatically enhanced over phosphated Nb2O5. The excellent catalytic performance with 100.0% sorbitol conversion and 62.5% isosorbide selectivity were obtained over the .8P/NBO-400 catalyst. Comparing with Nb2O5 catalysts, phosphated Nb2O5 catalysts regenerated through a simple calcination process showed no significant activity loss after recycling three runs.

      • KCI등재

        Production of diacylglycerols by esterification of oleic acid with glycerol catalyzed by diatomite loaded SO4 2-/TiO2

        Zhen Zhang,Hui Hua Huang,Xiang Ma,Guanghui Li,Yong Wang,Guo Sun,Yinglai Teng,Rian Yan,Ning Zhang,AiJun Li 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.53 No.-

        A new and efficient technique is described for the production of diacylglycerols (DAGs) by the esterification of oleic acid with glycerol catalyzed by diatomite-loaded SO4 2/TiO2. DAGs show some potential health benefits compared to triacylglycerols, and also can be used to produce the novel industrial plasticizer epoxy fatty acid methyl ester in material science. Diatomite-loaded SO4 2/TiO2 catalyst was prepared and characterized, and the selected conditions for the synthesis of DAGs were determined to be: reaction time = 6.0 h, temperature = 210 C, catalyst loading = 0.1% of the oleic acid weight, and mass ratio of oleic acid to glycerol = 2:1. Under these conditions, DAGs yield reached 59.6% with a purity of 69.6% after a one-stage molecular distillation. Diatomite-loaded SO4 2/TiO2 as a solid catalyst could be recycled and reused with high catalytic efficiency. Under the same conditions, diatomite-loaded SO4 2/TiO2 showed a better catalytic performance than the commercial solid acid SO4 2/ZrO2-Al2O3. Based on this, a two-step reaction method for the production of DAGs was performed and provided a yield similar to the one-step method (58.3% vs. 59.6%), but with a shorter reaction time (4 h vs. 6 h). It is concluded that a two-step reaction method could be a better alternative to the one-step production of DAGs in the presence of diatomite-loaded SO4 2/TiO2.

      • P53 and PCNA is Positively Correlated with HPV Infection in Laryngeal Epitheliopapillomatous Lesions in Patiets with Different Ethnic Backgrounds in Xinjiang

        Sun, Jie,Xiong, Ju,Zhen, Yan,Chen, Zhao-Lun,Zhang, Hua Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.11

        Objective: To explore the correlation of human papillomavious (HPV) infection with expression of p53 and proliferating cell nuclear antigen (PCNA) in patients with different ethnicity in Xinjiang, China. Methods: 166 biopsy specimens from 83 laryngeal squamous cell carcinomas (LSCC), 63 laryngeal papillomas (LP), and 20 laryngeal inflammatory polyps (LIP) were included in this study. HPV infection was determined by polymerase chain reaction (PCR) using specific types of HPV primers. Expression of p53 and PCNA was assessed using immunohistostaining. Results: The frequency of HPV 6/11 was higher in LP (33.3%) than in LSCC (9.6%) (P<0.0005), whereas the frequency of HPV 16/18 was higher in LSCC (37.3 %) than in LP (6.3%) (P<0.0005). Patients of the Han ethnic group with LSCC had a higher infection rate with HPV 6/11 or HPV 6/11 and HPV 16/18 coinfection than those of Uygur and Kazak ethnicity (P<0.05). Overexpression of p53 and PCNA were higher in LSCC (62.7%, 57.8%) than in LP (38%, 33.3%) (P<0.005, and P<0.005, respectively). That of p53 was not associated with lymph-node metastases and clinical stages, but overexpression of PCNA closely correlated with clinical stage. Conclusions: These results strongly implicate HPV6/11 infection in the carcinogenesis of LSCC and LP, respectively. There was a higher coincidence of increased malignancy of laryngeal tumors with overexpression of p53 and PCNA. Overexpression of p53 may serve as an early risk marker for malignant transformation in HPV infected cells while the overexpression of PCNA may serve as a late marker for progression of LSCC.

      • KCI등재

        H_3PW_12_O40/SiO_2 for sorbitol dehydration to isosorbide: High efficient and reusable solid acid catalyst

        Peng Sun,He Huang,Ding Hua Yu,Yi Hu,Zhen Chen Tang,Jiao Jiao Xia,Heng Li 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.1

        Tungstophosphoric acids (PW) supported on various metal oxides (SiO_2, γ_Al_2O_3, TiO_2, ZrO_2 and CeO_2)were synthesized and used as catalysts for sorbitol dehydration to isosorbide for the first time. 30% PW/SiO_2 exhibited the best catalytic performance for sorbitol dehydration, over which 56% isosorbide selectivity could be gained at a 95% sorbitol conversion at 250℃. The catalytic performance of regenerated 30% PW/SiO_2 catalysts by dichloromethane elution showed no loss after recycling five runs. Characterizations with UV-Vis, XRD, NH3-TPD and thermal analysis techniques revealed that PW had a good dispersion, and the primary Keggin structure was preserved after supporting PW on different supports. The interaction between PW and oxides resulted in different acidity of catalysts,which affected conversion of sorbitol and selectivity for isosorbide. The final acidity order of supported PW catalysts was the following: SiO_2>γ_Al_2O_3>TiO_2 ≈ZrO_2>CeO_2.

      • KCI등재

        Classification of rose petal colors based on optical spectrum and pigment content analyses

        Wang Hua,Fan Youwei,Yang Yuan,Zhang Hui,Li Maofu,Sun Pei,Zhang Xinzhu,Xue Zhen,Jin Wanmei 한국원예학회 2023 Horticulture, Environment, and Biotechnology Vol.64 No.2

        Roses ( Rosa sp.) are an important ornamental crop worldwide. Their colorful fl owers mainly refl ect an accumulation of anthocyanins and carotenoids. Developing a reliable method to classify rose petal color and identifying relationships between pigment contents and color space values may off er better evaluation criteria for rose varieties. In this study, we classifi ed 60 rose varieties into three groups based on their color parameters, corresponding to red varieties, white and yellow varie- ties, and pink and dark pink varieties. We measured the total pigment contents and identifi ed the underlying anthocyanins and carotenoids using both UV spectrophotometry and ultraperformance convergence chromatography coupled to mass spectrometry. Flower petals of white roses contained the lowest pigment levels, while those of yellow roses contained only carotenoids (40.65–244.42 μg/g) and mainly in the form of β-carotene and violaxanthin. The petals of pink and dark pink roses only accumulated anthocyanins (91.72–1703.93 μg/g) and mainly as cyanidin 3,5-diglucoside and cyanidin 3- O-glu- coside. The petals of red roses contained both large amounts of anthocyanins (1484.8–3806.22 μg/g) and small amounts of carotenoids (1.81–18.77 μg/g). We divided the 60 rose varieties tested here into fi ve color groups based on optical spectrum and pigment content analyses. We also explored the relationships between anthocyanin contents, carotenoid contents, and fl ower color space values using principal component analysis, Pearson’s correlations, and non-linear models. In addition to providing a more accurate system of rose petal color classifi cation, our results can be used to predict pigment contents based on color parameters.

      • SCOPUSKCI등재

        Synthesis and Biological Evaluation of Heterocyclic Ring-substituted Chalcone Derivatives as Novel Inhibitors of Protein Tyrosine Phosphatase 1B

        Chen, Zhen-Hua,Sun, Liang-Peng,Zhang, Wei,Shen, Qiang,Gao, Li-Xin,Li, Jia,Piao, Hu-Ri Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.5

        Protein tyrosine phosphatase 1B (PTP1B) is a key factor in negative regulation of the insulin pathway, and is a promising target for the treatment of type-II diabetes, obesity and cancer. Herein, compound ($\mathbf{4}$) was first observed to have moderate inhibitory activity against PTP1B with an $IC_{50}$ value of $13.72{\pm}1.53{\mu}M$. To obtain more potent PTP1B inhibitors, we synthesized a series of chalcone derivatives using compound ($\mathbf{4}$) as the lead compound. Compound $\mathbf{4l}$ ($IC_{50}=3.12{\pm}0.18{\mu}M$) was 4.4-fold more potent than the lead compound $\mathbf{4}$ ($IC_{50}=13.72{\pm}1.53{\mu}M$), and more potent than the positive control, ursolic acid ($IC_{50}=3.40{\pm}0.21{\mu}M$). These results may help to provide suitable drug-like lead compounds for the design of inhibitors of PTP1B as well as other PTPs.

      • SCOPUSKCI등재

        Phosphoric Acid Modified Nb<sub>2</sub>O<sub>5</sub>: A Selective and Reusable Catalyst for Dehydration of Sorbitol to Isosorbide

        Tang, Zhen-Chen,Yu, Ding-Hua,Sun, Peng,Li, Heng,Huang, He Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.12

        Niobium oxide ($Nb_2O_5$) and phosphated $Nb_2O_5$ were synthesized and used as catalysts for sorbitol dehydration to isosorbide. The characterization results of $N_2$ adsorption, XRD and $NH_3$-TPD revealed that the phosphoric acid modification could well prevent the crystallization of $Nb_2O_5$. And the amorphous phosphated $Nb_2O_5$ catalysts kept the relatively large surface area and stable acidity at high calcination temperature. The catalytic results showed that the selectivity to isosorbide could be dramatically enhanced over phosphated $Nb_2O_5$. The excellent catalytic performance with 100.0% sorbitol conversion and 62.5% isosorbide selectivity were obtained over the 0.8P/NBO-400 catalyst. Comparing with $Nb_2O_5$ catalysts, phosphated $Nb_2O_5$ catalysts regenerated through a simple calcination process showed no significant activity loss after recycling three runs.

      • Variation of Blood T Lymphocyte Subgroups in Patients with Non- small Cell Lung Cancer

        Wang, Wen-Jing,Tao, Zhen,Gu, Wei,Sun, Li-Hua Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.8

        Objectives: To study variation in T lymphocyte subgoups and its clinical significance in non-small cell lung cancer (NSCLC). Methods: Levels of CD3+, CD4+, CD8+, CD4+/CD8+, NK and Treg cells in peripheral blood of NSCLC cases and healthy adults were determined by flow cytometry. Results: CD3+, CD4+ and CD4+/CD8+ ratio and NK cells in NSCLCs were decreased significantly in comparison with the control group (P < 0.01), and decreased with increase in the clinical stage of NSCLC, while CD8+ cells demonstrated no significant change (P > 0.05). Treg cells were significantly more frequent than in the control group (P < 0.01), and increased with the clinical stage of NSCLC. Conclusion: The cellular immune function of the NSCLC patients is lowered. It is important to detect change of T lymphocyte subgroups by flow cytometry for the diagnosis, treatment and prognostic assessment of NSCLC patients.

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