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Liu X.-W.,Guizhou University | Yao Z.,Guizhou University | Yang J.,Guizhou University | Chen Z.-Y.,Guizhou University | And 5 more authors.
Tetrahedron | Year: 2016

A facile and efficient methodology was developed for the synthesis of isoxazole-fused spiropyrrolidine oxindoles 3-5 via a 1,3-dipolar cycloaddition reaction of 3-methyl-4-nitro-5-alkenyl-isoxazoles with azomethine ylides (thermally generated in situ from isatin derivatives and proline or thioproline or sarcosine). Products bearing adjacent quaternary-tertiary centers were smoothly obtained in high yields (up to 90% yield) with good diastereoselectivity (up to 20:1). Furthermore, their biological activity has been preliminarily demonstrated by in vitro evaluation against human prostate cancer cells PC-3, human lung cancer cells A549 and human leukemia cells K562 by the MTT-based assays using the commercially available standard drug Cisplatin as a positive control. These results suggested that most of isoxazole-fused spiropyrrolidine oxindoles 3-5 showed considerable cytotoxicities to these three cell lines K562, A549 and PC-3, and that isoxazole-fused spiropyrrolidine oxindoles may be potential leads for further biological screening. © 2016 Elsevier Ltd. Source

Gao P.-L.,Linyi Normal University | Li H.-Y.,Hospital Affiliated to Guiyang Medical College | Yang X.-F.,Linyi Normal University | Wang F.-Y.,Linyi Normal University | And 3 more authors.
World Chinese Journal of Digestology | Year: 2015

AIM: To explore the influence of Leptin mediated JAK/STAT3 signaling on human telomerase reverse transcriptase (hTERT) in human liver cancer cells (HepG2) and elucidate the molecular mechanisms by which Leptin induces hTERT expression in hepatocellular carcinoma cells. METHODS: The expression of ob-R in HepG2 cells was determined by Western blot. The expression of hTERT protein in cells after treatment with AG490 inhibitor was also detected by Western blot. Cell proliferation was detected by MTT method. The expression of hTERT mRNA was tested by RT-PCR, and the expression of hTERT protein was tested by Western blot. RESULTS: HepG2 cells expressed ob-R. Western blot analysis showed that the hTERT protein expression in AG490 treatment group and AG490 plus Leptin treatment group was lower than that of Leptin treatment group. HepG2 cell proliferation was reduced after STAT3-siRNA transfection. The expression of hTERT protein and hTERT mRNA was reduced in STAT3-siRNA transfected HepG2 cells after treatment with STAT3 inhibitor. CONCLUSION: HepG2 cells express ob-R. Lept in induc ed JAK-STAT3 s igna l ing downregulates the hTERT mRNA and protein expression in hepatocellular carcinoma cells. © 2015 Baishideng Publishing Group Inc. All rights reserved. Source

Qiao Z.,Hospital Affiliated to Guiyang Medical College | Shi L.-X.,Hospital Affiliated to Guiyang Medical College | Peng N.-C.,Hospital Affiliated to Guiyang Medical College | Xu S.-J.,Hospital Affiliated to Guiyang Medical College | And 9 more authors.
International Journal of Endocrinology | Year: 2013

Objective. To evaluate vitamin D status and serum parathyroid hormone (IPTH) of healthy adults living in Guiyang. Design and Participants. We conducted a cross-sectional evaluation in the General Community in Guiyang by cluster sampling method. The data was a part of 1510 participants (634 men, 876 women) aged 20-79 years median 45.2 years from November 2009 to February 2010 in Guiyang Health Measures Survey. Measurements. Aradioimmunoassay was used to measure the level of 25-hydroxyvitamin D [25(OH)D] and intact parathyroid hormone (iPTH). Results.The mean serum 25(OH)D level was (20.4 ± 9.0) ng/mL and the highest level among participants aged 40-59 years (22.8 ng/mL). The mean serum PTH level was (32.1 ± 13.7) pg/mL and the lowest level among participants aged 40-50 years (30.8 ng/mL). Serum 25(OH)D was below 50 nmol/liter in 52.3%, below 75 nmol/liter in 84.6%, and above 75 nmol/liter in 15.4% of the respondents. Secondary hyperparathyroidism was 5.4% (5.4% among men and 4.6% among women). The prevalence of secondary hyperparathyroidism increased (5.8%, 6.5%, and 7.1%, resp.) with decreasing serum 25(OH)D levels among subjects who were 30 to 20, 19.9 to 10, and <10 ng/mL, respectively. Serum 25(OH)D was inversely associated with serum PTH. Conclusions. Vitamin D insufficiency and its complication of secondary hyperparathyroidism are common. © 2013 Zhang Qiao et al. Source

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