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Liang Z.,First Peoples Hospital of Jining | Li Y.,Central Hospital of Zibo
Solid State Sciences | Year: 2012

A highly sensitive and selective small molecule detection platform has been developed using aptamers immobilized on electrode surface. In our system, two aptamers were used - one of which is for ATP recognition and the other is for signal produce. We designed two probes L1 (containing ATP aptamer and a part of hemin aptamer) and L2 (containing the complementary strand of ATP aptamer and the rest of hemin aptamer) and immobilized L1 on electrode surface. L2 was used to hybridize to L1 and form L1-L2 duplex which brought the two parts of hemin aptamer into close proximity. Then hemin can be captured by this duplex and detected by electrochemical methods. When we introduced ATP into the system, the ATP binding destroyed the duplex and L2 diffused into the solution. As a result, hemin cannot be captured to bring electrochemical signal. © 2012 Elsevier Masson SAS. All rights reserved. Source

Fei Y.,Huazhong University of Science and Technology | Wang J.,Huazhong University of Science and Technology | Liu W.,Central Hospital of Zibo | Zuo H.,Huazhong University of Science and Technology | And 4 more authors.
Molecular Medicine Reports | Year: 2012

CD151 is a member of the tetraspanin family that is implicated as a promoter of the tumor metastasis of malignant cells. Tetraspanins form membrane complexes with integrins. In the present study, we constructed a CD151-AAA mutant to assess the roles of Rac, cdc42 and phospho-Rac/cdc42 (P-Rac/cdc42) and the effects of CD151-integrin complexes on the proliferation, migration and invasion of HepG2 cells. The pAAV-CD151 and pAAV-CD151-AAA mutant plasmids were constructed and used to transiently transfect HepG2 cells using the Qiagen Attractene transfection reagent. Following transfection, the expression of CD151 was determined by western blotting. A cell proliferation assay was performed using the cell counting kit-8 (CCK-8) method, cell migration was assessed by a cell wound-healing assay and cell invasion was evaluated in microchemotaxis chambers using FBS as the chemotactic stimulus. The potential involvement of various signaling pathways was explored using relevant antibodies. The association between CD151 and integrins was evaluated by immunoblotting analysis. We found that CD151 promoted cell proliferation, migration and chemotaxis and increased P-Rac/cdc42 activity. The CD151-AAA mutant had reduced cellular proliferation, migration and invasion compared with the CD151 mutant. Moreover, the CD151-AAA mutant abrogated the association between CD151 and integrins. These data suggest that CD151 forms complexes by interacting with integrins, particularly α3β1 and α6β1, and thereby affects the functioning of the HepG2 cells. The mechanism is possibly related to the Rac, cdc42 and P-Rac/cdc42 signaling pathways. Source

Sun Y.,Tongji University | Zhang Y.,Shanghai JiaoTong University | Li N.,Central Hospital of Zibo | Zhang H.,Tongji University | And 2 more authors.
Experimental and Therapeutic Medicine | Year: 2014

Cells continually adjust their gene expression profiles in order to adapt to the availability of nutrients. Glucose is a major regulator of pxancreatic β-cell function and cell growth. However, the mechanism of β-cell adaptation to high levels of glucose remains uncertain. To identify the specific targets responsible for adaptation to high levels of glucose, the differentially expressed genes from primary rat islets treated with 3.3 and 16.7 mmol/l glucose for 24 h were detected by DNA microarray. The results revealed that the expression levels of genes that encode enzymes required for de novo cholesterol biosynthesis [3-hydroxy-3-methylglutaryl-CoA synthase 1 (Hmgcs1), 3-hydroxy-3-methylglutaryl-CoA reductase (Hmgcr), mevalonate (diphospho) decarboxylase (Mvd), isopentenyl-diphosphate δ-isomerase 1 (Idi1), squalene epoxidase (Sqle) and 7-dehydrocholesterol reductase (Dhcr7)] were significantly increased in islets treated with high levels of glucose compared with those in the islets treated with lower glucose levels. Quantitative polymerase chain reaction further confirmed that glucose stimulated the expression levels of these genes in a dose-and time-dependent manner. A similar result was obtained in islets isolated from rats subjected to 12, 24, 48 and 72 h of continuous glucose infusion. It has previously been recognized that cholesterol homeostasis is important for β-cell function. The present study provides, to the best of our knowledge, the first evidence for the involvement of the de novo cholesterol biosynthesis pathway in the adaptation of rat islets to high levels of glucose in vitro and in vivo. Source

Liu W.-F.,Huazhong University of Science and Technology | Zuo H.-J.,Huazhong University of Science and Technology | Chai B.-L.,Huazhong University of Science and Technology | Peng D.,Huazhong University of Science and Technology | And 5 more authors.
International Journal of Biochemistry and Cell Biology | Year: 2011

Tetraspanin CD151 mainly associates with laminin-binding integrins and forms CD151-integrin complex. We previously reported that CD151 could be a potential target for angiogenesis, but the mechanisms involved are still unclear. This study investigated the role of CD151-integrin complex in angiogenesis and the signaling mechanisms involved. Here we showed that CD151 and CD151-AAA mutant were both well expressed at the protein level. CD151 gene transfer promoted angiogenesis and improved skin temperature of the lateral ischemic hindlimb, whereas CD151-AAA mutant abrogated the increase in capillary density and skin temperature. Further, CD151-AAA mutant failed to activate the FAK, ERK, PI3K/Akt/eNOS, and Rac1/Cdc42 signaling pathways. Moreover, CD151-AAA mutant was unavailable to promote bovine aortic endothelial cells (BAECs) proliferation and migration, in contrast to the effects of CD151. The results suggested that formation of CD151-integrin complex was likely to be a prerequisite for CD151-induced angiogenesis and signaling pathways. © 2011 Elsevier Ltd. All rights reserved. Source

Wei Y.,Shandong University | Ji X.-B.,Liaocheng Peoples Hospital | Wang Y.-W.,Shandong University | Wang J.-X.,Peoples Hospital of Rizhao | And 9 more authors.
Blood | Year: 2016

This study compared the efficacy and safety of high-dose dexamethasone (HD-DXM) and conventional prednisone (PDN) on the largest cohort to date as first-line strategies for newly diagnosed adult primary immune thrombocytopenia (ITP). Patients enrolled were randomized to receive DXM 40 mg/d for 4 days (n 5 95, nonresponders received an additional 4-day course ofDXM) or prednisone 1.0mg/kg daily for 4 weeks and then tapered (n 5 97). One or 2 courses of HD-DXM resulted in a higher incidence of overall initial response (82.1% vs 67.4%, P 5 .044) and complete response (50.5% vs 26.8%, P 5 .001) compared withprednisone. Time to responsewas shorter in theHD-DXMarm(P .001), and a baseline bleeding score 8 was associated with a decreased likelihood of initial response. Sustained response was achieved by 40.0% of patients in the HD-DXM arm and 41.2% in the PDN arm (P 5 .884). Initial complete response was a positive indicator of sustained response, whereas presence of antiplatelet autoantibodies was a negative indicator. HD-DXM was generally tolerated better. We concluded that HD-DXM could be a preferred corticosteroid strategy for first-linemanagement of adult primary ITP. This study is registered at www.clinicaltrials.gov as #NCT01356511. © 2016 by The American Society of Hematology. Source

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