951
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Wu L, Xi B, Zhang M, Shen Y, Zhao X, Wang T, Cheng H, Hou D, Liu G, Wang X, Mi J. A sex-specific effect of the CYP17A1 SNP rs11191548 on blood pressure in Chinese children. J Hum Hypertens 2011; 26:731-6. [DOI: 10.1038/jhh.2011.96] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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952
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Shi Z, Wang S, Ma L, Lu W, Zhao X, Yang Y, Li X, Wang H, Sun W. Acupuncture: how objective is the evidence from randomised clinical trials? BJOG 2011; 118:1141-2; author reply 1142. [PMID: 21749612 DOI: 10.1111/j.1471-0528.2011.02978.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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953
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Cao J, Zhang X, Wang Q, Jia L, Zhang Y, Zhao X. Influence of flavonoid extracts from celery on oxidative stress induced by dichlorvos in rats. Hum Exp Toxicol 2011; 31:617-25. [PMID: 22045891 DOI: 10.1177/0960327111426585] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The present work was to investigate the effects of flavonoid extracts from celery on oxidative stress induced by dichlorvos (DIC) in male Wistar rats maintained on a normal diet. The rats were given DIC through intragastric administration by the dose of 7.2 mg/kg·body weight (bw)/day and additionally added 5% flavonoid extracts to the diet for 4 weeks continuously. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione-S-transferase (GST) and the content of malondialdehyde (MDA) in livers of rats were measured at the end of the experiment. Under the influence of DIC, there were significant decrease in the activities of SOD, CAT and GST and significant increase in GPx activity and MDA content. The results also showed that the activities of SOD, GST and CAT in the DIC-treated group declined significantly when compared with the flavonoid extracts group and the DIC + flavonoid extracts group, respectively. With regard to GPx activity and MDA content, significant increase were showed in the DIC-treated group in comparison to those in the flavonoid extracts group and the DIC + flavonoid extracts group, respectively. The observations presented lead us to conclude the harmful effects of DIC during the exposure and the protective role of flavonoids in minimizing these effects.
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954
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Wang H, Li Q, Wang T, Yang G, Wang Y, Zhang X, Sang Q, Wang H, Zhao X, Xing Q, Shi J, He L, Wang L. A common polymorphism in the human aromatase gene alters the risk for polycystic ovary syndrome and modifies aromatase activity in vitro. Mol Hum Reprod 2011. [DOI: 10.1093/molehr/gar046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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955
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Iyengar BG, Chou CJ, Vandamme KM, Klose MK, Zhao X, Akhtar-Danesh N, Campos AR, Atwood HL. Silencing synaptic communication between random interneurons duringDrosophilalarval locomotion. GENES BRAIN AND BEHAVIOR 2011; 10:883-900. [DOI: 10.1111/j.1601-183x.2011.00729.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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956
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Zhao X, Qian D, Wu N, Yin Y, Song M, Yu S, Chen J, Cui B. Spleen recruits endothelial progenitor cells (EPCs) via SDF-1/CXCR4 axis. Heart 2011. [DOI: 10.1136/heartjnl-2011-300867.254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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957
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Zhao X, Qian D, Wu N, Yin Y, Song M, Yu S, Chen J, Cui B. Spleen recruits endothelial progenitor cells (EPCs) via SDF-1/CXCR4 axis(*). BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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958
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Zhao X, Yu X. Role of ischaemic postconditioning regulates endoplasmic reticulum stress in prevention of myocardial reperfusion injury. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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959
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Liu Y, Zhao X. The epidemiological study of the prevalence and risk factors of hypertension among residents of Oroqen nationality. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.265] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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960
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Rao N, Trotti A, Kim J, Schell M, Zhao X, Amdur R, Brizel D, Chambers M, Miyamoto C, Rosenthal D. Phase II Multicenter Trial of Caphosol for the Reduction of Mucositis in Patients Receiving Radiation Therapy for Head and Neck Cancer. Int J Radiat Oncol Biol Phys 2011. [DOI: 10.1016/j.ijrobp.2011.06.150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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961
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Naryshkin N, Narasimhan J, Dakka A, Gabbeta V, Haley M, Crona J, Jung S, Vazirani P, Furia B, Qi H, Woll M, Yang T, Lee S, Choi S, Chen G, Zhang S, Zhang N, Huang S, Li C, Turpoff A, Hedrick J, Zhao X, Mollin A, Letinski S, Risher N, Paushkin S, Kobayashi D, McCarthy K, Pleiss M, Chen K, Almstead N, Colacino J, Babiak J, Peltz S, Karp G, Weetall M, Welch E. P3.12 Small molecule compounds that correct alternative splicing of the SMN2 gene and restore SMN protein expression and function. Neuromuscul Disord 2011. [DOI: 10.1016/j.nmd.2011.06.906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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962
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Zhao X, Yu X. Ischaemic postconditioning protects cardiomyocyte from ischaemia/reperfusion injury by attenuating endoplasmic reticulum stress via PI3K-Akt pathway. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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963
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Xiong TL, Zhang XG, Zhao X, Ma HF. Research of induced pluripotent stem cells fused with cardiac myocyte. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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964
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Li L, Wang R, Wilcox D, Zhao X, Song J, Lin X, Kohlbrenner WM, Fesik SW, Shen Y. Tumor vasculature is a key determinant for the efficiency of nanoparticle-mediated siRNA delivery. Gene Ther 2011; 19:775-80. [PMID: 21956688 PMCID: PMC3389750 DOI: 10.1038/gt.2011.146] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Delivering small interfering RNA (siRNA) to tumors using clinically viable formulations remains the primary technical hurdle that prevents the development of siRNA therapy for cancer treatment. Over the past several years, significant effort has been devoted to explore novel delivery strategies, whereas relatively little attention has been paid to understand the impact of physiological constrains such as tumor vasculature on the efficiency of siRNA delivery. Using the previously described positive-readout tumor models where successful siRNA delivery leads to an upregulation of β-galactosidase within tumor sections, we analyzed the spatial distribution of localized target knockdown within tumor sections relative to tumor hypoxia and found that stable nucleic acid lipid particle (SNALP), a lipid nanoparticle-based delivery system, predominantly delivers siRNA to areas adjacent to functional tumor blood vessels. Increasing tumor vascularity by ectopic expression of VEGF resulted in more efficient siRNA delivery to tumors using SNALP. SNALP-mediated delivery of a siRNA-targeting Ran GTPase led to target knockdown and significant antitumor efficacy in the highly vascularized HepG2-derived liver tumors, but not in the poorly vascularized HCT-116-derived liver tumors. These results highlight the significant impact of tumor vasculature on siRNA delivery and call for a more focused effort on addressing tumor penetration after extravasation, an area of only limited attention currently.
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965
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Bushnell CD, Olson DM, Zhao X, Pan W, Zimmer LO, Goldstein LB, Alberts MJ, Fagan SC, Fonarow GC, Johnston SC, Kidwell C, Labresh KA, Ovbiagele B, Schwamm L, Peterson ED. Secondary preventive medication persistence and adherence 1 year after stroke. Neurology 2011; 77:1182-90. [PMID: 21900638 PMCID: PMC3265047 DOI: 10.1212/wnl.0b013e31822f0423] [Citation(s) in RCA: 181] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2011] [Accepted: 05/25/2011] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVE Data on long-term use of secondary prevention medications following stroke are limited. The Adherence eValuation After Ischemic stroke-Longitudinal (AVAIL) Registry assessed patient, provider, and system-level factors influencing continuation of prevention medications for 1 year following stroke hospitalization discharge. METHODS Patients with ischemic stroke or TIA discharged from 106 hospitals participating in the American Heart Association Get With The Guidelines-Stroke program were surveyed to determine their use of warfarin, antiplatelet, antihypertensive, lipid-lowering, and diabetes medications from discharge to 12 months. Reasons for stopping medications were ascertained. Persistence was defined as continuation of all secondary preventive medications prescribed at hospital discharge, and adherence as continuation of prescribed medications except those stopped according to health care provider instructions. RESULTS Of the 2,880 patients enrolled in AVAIL, 88.4% (2,457 patients) completed 1-year interviews. Of these, 65.9% were regimen persistent and 86.6% were regimen adherent. Independent predictors of 1-year medication persistence included fewer medications prescribed at discharge, having an adequate income, having an appointment with a primary care provider, and greater understanding of why medications were prescribed and their side effects. Independent predictors of adherence were similar to those for persistence. CONCLUSIONS Although up to one-third of stroke patients discontinued one or more secondary prevention medications within 1 year of hospital discharge, self-discontinuation of these medications is uncommon. Several potentially modifiable patient, provider, and system-level factors associated with persistence and adherence may be targets for future interventions.
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966
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Maeda Y, Nagano K, Yamashita T, Kanasaki S, Inoue M, Zhao X, Abe Y, Kamada H, Tsutsumi Y, Tsunoda S. 5028 POSTER Functional Analysis of a Novel Breast Cancer Related Protein, Ephrin Receptor A10. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)71470-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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967
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Kanasaki S, Nagano K, Yamashita T, Maeda Y, Inoue M, Zhao X, Abe Y, Kamada H, Tsutsumi Y, Tsunoda S. 5029 POSTER Possibility of Ephrin Receptor A10 as a Drug Target in Triple Negative Breast Cancer. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)71471-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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968
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Hersleth HP, Zhao X, Magliozzo RS, Andersson KK. Combining X-ray diffraction and in situspectroscopy to study haem proteins. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311096085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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969
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Wang H, Ji Y, Zeng X, Zhao X, Huang W. In situX-ray diffraction study of the phase transitions in C4 olefin catalysts. Acta Crystallogr A 2011. [DOI: 10.1107/s010876731109386x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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970
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Cong DY, Zhang YD, Esling C, Wang YD, Zhao X, Zuo L. Modification of preferred martensitic variant distribution by high magnetic field annealing in an Ni–Mn–Ga alloy. J Appl Crystallogr 2011. [DOI: 10.1107/s0021889811027671] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The preferred martensitic variant distribution in Ni53Mn25Ga22ferromagnetic shape memory alloy (FSMA) samples annealed without and with a high magnetic field of 12 T applied during the annealing process was investigated by electron backscatter diffraction. It is revealed that the high magnetic field applied during annealing enhances the regular arrangement of martensitic variants from the morphological point of view and effectively modifies the preferred orientation distribution of martensitic variants without changing the misorientation between them from the crystallographic point of view. Only one texture component, \{ 1{\overline 1}0\} \langle 33{\overline 2}\rangle, exists in the sample annealed without a magnetic field, whereas two additional texture components, \{ 4{\overline 6} 3\} \langle 31{\overline 2}\rangle and \{ 1\overline 1 0\} \langle 110 \rangle, are developed in the sample annealed in a high magnetic field. The new finding that the preferred martensitic variant distribution can be efficiently modified by introducing a high magnetic field during the annealing process will shed light on the development of high-performance polycrystalline FSMAsvianovel processing techniques.
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971
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Zhao X, Yang ZB, Yang WR, Wang Y, Jiang SZ, Zhang GG. Effects of ginger root (Zingiber officinale) on laying performance and antioxidant status of laying hens and on dietary oxidation stability. Poult Sci 2011; 90:1720-7. [PMID: 21753209 DOI: 10.3382/ps.2010-01280] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To investigate the effects of ginger root (Zingiber officinale) on laying performance and antioxidant status of laying hens and on dietary oxidation stability, 675 Hy-Line brown laying hens at 27 wk of age were randomly allocated to 5 treatments with 5 replicates in a complete randomized design. Laying hens were fed corn-soybean meal based diets and supplemented with 0, 5, 10, 15, or 20 g of ginger powder/kg of diet for 10 wk. The ADFI, laying rate, average egg weight, egg mass, and feed conversion of each replicate were measured weekly. Blood samples from 10 laying hens and 15 egg samples/treatment were obtained on d 35 and 70 of the experiment to determine the serum or egg yolk antioxidant enzymatic activities. Three separate batches of each treatment diet were also made at the beginning of the experiment and stored at 20°C. Subsamples were taken at 10-d intervals to determine the dietary oxidation stability over a 60-d period. All laying hens had similar ADFI, laying rate, average egg weight, and feed conversion. However, laying hens supplemented with ginger powder had higher (P = 0.024) egg mass than the control group. Supplementation of ginger powder increased (P < 0.05) the serum and egg yolk antioxidant enzymatic activities of laying hens on d 35 and 70. Increasing ginger powder from 0 to 20 g/kg of diet linearly increased (P < 0.05) the peroxide value but linearly reduced (P < 0.05) the acid value of lipid extracted from stored diets for the first 30 d, but not for the second 30 d. Dietary supplementation of ginger powder improved laying performance and serum and egg yolk antioxidant status and enhanced dietary oxidation stability in a dose-dependent manner. The optimum supplementation rate of ginger powder in the diet of laying hens appeared to be between 10 and 15 g/kg of diet.
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972
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Huang B, Zhao X, Zheng LB, Zhang L, Ni B, Wang YW. Different expression of tissue inhibitor of metalloproteinase family members in rat dorsal root ganglia and their changes after peripheral nerve injury. Neuroscience 2011; 193:421-8. [PMID: 21782897 DOI: 10.1016/j.neuroscience.2011.07.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Revised: 07/12/2011] [Accepted: 07/12/2011] [Indexed: 12/13/2022]
Abstract
Matrix metalloproteinase 9 (MMP9) and MMP2 are important in the development and maintenance of neuropathic pain behavior induced by peripheral nerve injury. The enzymatic activity of MMP9 and MMP2 is balanced specifically by tissue inhibitor of metalloproteinase 1 (TIMP1) and TIMP2, respectively. In present study, we measured the effect of peripheral nerve injury on the expression of TIMP1 and TIMP2 in adult dorsal root ganglia (DRG). A dramatic increase of TIMP1 mRNA and a decrease of TIMP2 in DRG after sciatic nerve transection (SNT) were displayed through a real-time PCR method. Furthermore, data showed by in situ hybridization that TIMP1 mRNA was only localized in DRG satellite cells under normal conditions. TIMP1 mRNA was increased in satellite cells, and induced within sensory neurons after SNT. Analysis of neuronal profiles showed that induced TIMP1 mRNA was mainly contained in small and medium DRG neurons. Further study displayed that induced TIMP1 mRNA was predominantly present in activating transcription factor 3 (ATF3)-positive injured DRG neurons. Comparatively, TIMP2 mRNA was mostly contained within sensory neurons and the overall amount decreased at the late stage after nerve injury. These data showed different change of TIMPs in DRG after peripheral nerve injury.
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973
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Zhao X, Geltinger C, Kishikawa S, Ohshima K, Murata T, Nomura N, Nakahara T, Yokoyama KK. Treatment of mouse melanoma cells with phorbol 12-myristate 13-acetate counteracts mannosylerythritol lipid-induced growth arrest and apoptosis. Cytotechnology 2011; 33:123-30. [PMID: 19002819 DOI: 10.1023/a:1008129616127] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Mannosylerythritol lipid (MEL), an extracellularglycolipid from yeast, induces the differentiation ofHL-60 promyelocytic leukemia cells towardsgranulocytes. We show here that MEL is also a potentinhibitor of the proliferation of mouse melanoma B16cells. Flow-cytometric analysis of the cell cycle ofMEL-treated B16 cells revealed the accumulation ofcells in the sub-G(0)/G(1) phase, which is a hallmark ofcells undergoing apoptosis. Treatment of B16 cellsfor 24 h with phorbol 12-myristate 13-acetate (PMA),an activator of protein kinase C (PKC), did notinterfere with the growth and survival of the cells,but it effectively counteracted the MEL-induced growtharrest and apoptosis. The activity of PKC was reducedin B16 cells treated with MEL at a concentration atwhich MEL induced apoptosis. However, incubation withPMA in addition to MEL reversed this reduction in theactivity of PKC. These results suggest thatconverging signaling pathways are triggeredindependently by MEL and PMA and that the signalsmight both be mediated by PKC.
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974
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Hong Y, Yang D, Liu W, Zhao X, Chen X, Li L. Dyslipidemia in relation to body mass index and insulin resistance in Chinese women with polycystic ovary syndrome. J BIOL REG HOMEOS AG 2011; 25:365-374. [PMID: 22023761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Dyslipidemia is a common metabolic disorder in women with polycystic ovary syndrome (PCOS) and has been reported to be different in PCOS sufferers from various ethnic and geographic backgrounds. This study aims to investigate the prevalence of dyslipidemia in Chinese women with PCOS and its relationship to body mass index (BMI) and insulin resistance (IR). In this paper, a retrospective study was performed on 507 PCOS patients and 1246 age- and BMI-matched controls. Anthropometric indices of hormonal, adiposity, and metabolic variables were measured. All patients were divided into subgroups according to BMI and the homeostasis model assessment (HOMA) values. Accordingly, the prevalence of IR was 38.1 percent in our subjects. We found that mean fasting total triglyceride, low density lipoprotein (LDL) cholesterol and total cholesterol levels were significantly higher and the mean high density lipoprotein (HDL) cholesterol level was significantly lower in the IR group than in the non-IR (NIR) group. The prevalence of dyslipidemia was 24.7 percent in PCOS patients and the prevalence of dyslipidemia was significantly higher in the IR group than in the NIR group (39.9 percent vs 15.3 percent, P<0.05). The HOMA index was found to be positively correlated with TG, TC and LDL, and negatively correlated with HDL. TG and HDL levels remained significantly correlated with HOMA even after adjustment for BMI. Generally, the prevalence of various patterns of dyslipidemia in PCOS patients increased with HOMA value. In conclusion, the prevalence of IR and dyslipidemia were both found to be high in PCOS women in our study, although no higher than other ethnicities. Lipid abnormality was demonstrated to be associated with IR and BMI in Chinese PCOS women. We speculate that insulin sensitizer might ameliorate dyslipidemia through improving IR in PCOS women.
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975
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Kawamura S, Sato I, Wada T, Yamaguchi K, Li Y, Li D, Zhao X, Ueno S, Aoki H, Tochigi T, Kuwahara M, Kitamura T, Takahashi K, Moriya S, Miyagi T. Plasma membrane-associated sialidase (NEU3) regulates progression of prostate cancer to androgen-independent growth through modulation of androgen receptor signaling. Cell Death Differ 2011; 19:170-9. [PMID: 21681193 DOI: 10.1038/cdd.2011.83] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Prostate cancers generally become androgen-independent and resistant to hormone therapy with progression. To understand the underlying mechanisms and facilitate the development of novel treatments for androgen-independent prostate cancer, we have investigated plasma membrane-associated sialidase (NEU3), the key enzyme for ganglioside hydrolysis participating in transmembrane signaling. We have discovered NEU3 to be upregulated in human prostate cancer compared with non-cancerous tissue, correlating with the Gleason score. NEU3 silencing with siRNA in prostate cancer PC-3 and LNCaP cells resulted in increased expression of differentiation markers and in cell apoptosis, but decrease in Bcl-2 as well as a progression-related transcription factor, early growth response gene (EGR-1). In androgen-sensitive LNCaP cells, forced overexpression of NEU3 significantly induced expression of EGR-1, androgen receptor (AR) and PSA both with and without androgen, the cells becoming sensitive to androgen. The NEU3-mediated induction was abrogated by inhibitors for PI-3 kinase and MAP kinase and more specifically by their silencing in the absence of androgen, being confirmed by increased phosphorylation of AKT and ERK1/2 in NEU3 overexpressing cells. NEU3 siRNA introduction caused reduction of cell growth of an androgen-independent PC-3 cells in culture and of transplanted tumors in nude mice. These data suggest that NEU3 regulates tumor progression through AR signaling, and thus be a potential tool for diagnosis and therapy of androgen-independent prostate cancer.
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