Fractional differential constitutive relationships are introduced to depict the history of dynamic stress inten- sity factors （DSIFs） for a semi-infinite crack in infinite viscoelastic material subjected to anti-pla...Fractional differential constitutive relationships are introduced to depict the history of dynamic stress inten- sity factors （DSIFs） for a semi-infinite crack in infinite viscoelastic material subjected to anti-plane shear impact load. The basic equations which govern the anti-plane deformation behavior are converted to a fractional wave-like equation. By utilizing Laplace and Fourier integral transforms, the fractional wave-like equation is cast into an ordinary differential equation （ODE）. The unknown function in the solution of ODE is obtained by applying Fourier transform directly to the boundary conditions of fractional wave-like equation in Laplace domain instead of solving dual integral equations. Analytical solutions of DSIFs in Laplace domain are derived by Wiener-Hopf technique and the numerical solutions of DSIFs in time domain are obtained by Talbot algorithm. The effects of four parameters α, β, b1, b2 of the fractional dif- ferential constitutive model on DSIFs are discussed. The numerical results show that the present fractional differential constitutive model can well describe the behavior of DSIFs of anti-plane fracture in viscoelastic materials, and the model is also compatible with solutions of DSIFs of anti-plane fracture in elastic materials.展开更多
Objective To investigate the occurrence of basal core promoter(BCP) and pre-C mutations in patients with hepatitis B virus(HBV) infection in Gansu Province, China, and to analyze the correlation of HBV mutation and HB...Objective To investigate the occurrence of basal core promoter(BCP) and pre-C mutations in patients with hepatitis B virus(HBV) infection in Gansu Province, China, and to analyze the correlation of HBV mutation and HBV genotype with primary hepatocellular carcinoma(HCC). Methods PCR-RFLP was applied to detect HBV subgenotypes, and the presence of the pre-C and BCP mutations in 62 patients with HCC, 70 patients with hepatitis B induced liver cirrhosis(LC) and 90 patients with chronic hepatitis B(CHB). Results In HCC patients, genotype C was the major genotype(70.97%). The pre-C mutation was found in 59.68%, 31.43% and 16.67% patients with HCC, LC and CHB, respectively. The frequency of BCP mutations was significantly different between patients with HCC, LC and CHB(74.19%, 51.43% and 37.78%, respectively; χ2=30.727, 19.540, respectively, P < 0.01). Patients in HCC group had a higher incidence of pre-C as well as BCP mutations compared to the other groups. The prevalence of pre-C and BCP mutations was significantly higher in patients with genotype C1(44.32% and 69.32%, respectively) compared to patients with other subgenotypes(P < 0.05). Conclusions The incidence of pre-C and BCP mutations increases with disease progression. Pre-C and BCP mutations frequently occur in patients with genotype C1. HBV genotype C, pre-C mutations and BCP mutations are closely related to the occurrence of HCC.展开更多
Fibroblast-like synoviocytes （FLSs） contribute to synovial hyperplasia in rheumatoid arthritis （RA）. Smoothened （Smo） is a key component of sonic hedgehog （Shh） signaling and contributes to tumor cell prolifer...Fibroblast-like synoviocytes （FLSs） contribute to synovial hyperplasia in rheumatoid arthritis （RA）. Smoothened （Smo） is a key component of sonic hedgehog （Shh） signaling and contributes to tumor cell proliferation. The objective of this study was to investigate the role of Smo in RA synoviocyte proliferation. FLSs were isolated from RA synovium. Shh signaling was studied using a Smo antagonist （GDC-0449） and small interfering RNA （siRNA） targeting the Smo gene in FLSs. Cell proliferation was quantified by using kit-8 assay and cell cycle distribution and apoptosis were evaluated by flow cytometry. Cell cycle-related genes and proteins were detected by real-time PCR and western blot. FLSs treated with GDC-0449 or Smo-siRNA showed significantly decreased proliferation compared to controls （P〈0.05）. Incubation with GDC-0449 or transfection with Smo-siRNA resulted in a significant increase of G1 phase cells compared to controls （P 〈 0.05）. Cell cycle arrest was validated by the significant increase in cyclin D1 and E1 mRNA expression, decrease in cyclin-dependent kinase p21 mRNA expression in Smo-siRNA transfected cells （P 〈 0.05）. Protein expression of cyclin D1 was also downregulated after Smo gene knockdown （P 〈0.05）.The results suggest that Shh signaling plays an important role in RA-FLSs proliferation in a Smo-dependent manner and may contribute to synovial hyperplasia. Targeting Shh signaling may help control joint damage in patients with RA.展开更多
基金supported by the National Natural Science Foundation of China(11072060)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Fractional differential constitutive relationships are introduced to depict the history of dynamic stress inten- sity factors （DSIFs） for a semi-infinite crack in infinite viscoelastic material subjected to anti-plane shear impact load. The basic equations which govern the anti-plane deformation behavior are converted to a fractional wave-like equation. By utilizing Laplace and Fourier integral transforms, the fractional wave-like equation is cast into an ordinary differential equation （ODE）. The unknown function in the solution of ODE is obtained by applying Fourier transform directly to the boundary conditions of fractional wave-like equation in Laplace domain instead of solving dual integral equations. Analytical solutions of DSIFs in Laplace domain are derived by Wiener-Hopf technique and the numerical solutions of DSIFs in time domain are obtained by Talbot algorithm. The effects of four parameters α, β, b1, b2 of the fractional dif- ferential constitutive model on DSIFs are discussed. The numerical results show that the present fractional differential constitutive model can well describe the behavior of DSIFs of anti-plane fracture in viscoelastic materials, and the model is also compatible with solutions of DSIFs of anti-plane fracture in elastic materials.
文摘Objective To investigate the occurrence of basal core promoter(BCP) and pre-C mutations in patients with hepatitis B virus(HBV) infection in Gansu Province, China, and to analyze the correlation of HBV mutation and HBV genotype with primary hepatocellular carcinoma(HCC). Methods PCR-RFLP was applied to detect HBV subgenotypes, and the presence of the pre-C and BCP mutations in 62 patients with HCC, 70 patients with hepatitis B induced liver cirrhosis(LC) and 90 patients with chronic hepatitis B(CHB). Results In HCC patients, genotype C was the major genotype(70.97%). The pre-C mutation was found in 59.68%, 31.43% and 16.67% patients with HCC, LC and CHB, respectively. The frequency of BCP mutations was significantly different between patients with HCC, LC and CHB(74.19%, 51.43% and 37.78%, respectively; χ2=30.727, 19.540, respectively, P < 0.01). Patients in HCC group had a higher incidence of pre-C as well as BCP mutations compared to the other groups. The prevalence of pre-C and BCP mutations was significantly higher in patients with genotype C1(44.32% and 69.32%, respectively) compared to patients with other subgenotypes(P < 0.05). Conclusions The incidence of pre-C and BCP mutations increases with disease progression. Pre-C and BCP mutations frequently occur in patients with genotype C1. HBV genotype C, pre-C mutations and BCP mutations are closely related to the occurrence of HCC.
基金This work was supported in part by grants from the National Natural Science Foundation of China （81072480）, from the Natural Science Foundation of Guangdong Province （$2012020010927）, and from the Science and Technology Program of Guangdong Province （2013B021800076） （Jian-lin Huang） the major projects from Science and Technology Program of Guangzhou City, from the National Natural Science Foundation of Guangdong Province, from the Department of Education of Guangdong Province, and grants from NIH AR059103 and NIH AI084359 （Song Guo Zheng）.
文摘Fibroblast-like synoviocytes （FLSs） contribute to synovial hyperplasia in rheumatoid arthritis （RA）. Smoothened （Smo） is a key component of sonic hedgehog （Shh） signaling and contributes to tumor cell proliferation. The objective of this study was to investigate the role of Smo in RA synoviocyte proliferation. FLSs were isolated from RA synovium. Shh signaling was studied using a Smo antagonist （GDC-0449） and small interfering RNA （siRNA） targeting the Smo gene in FLSs. Cell proliferation was quantified by using kit-8 assay and cell cycle distribution and apoptosis were evaluated by flow cytometry. Cell cycle-related genes and proteins were detected by real-time PCR and western blot. FLSs treated with GDC-0449 or Smo-siRNA showed significantly decreased proliferation compared to controls （P〈0.05）. Incubation with GDC-0449 or transfection with Smo-siRNA resulted in a significant increase of G1 phase cells compared to controls （P 〈 0.05）. Cell cycle arrest was validated by the significant increase in cyclin D1 and E1 mRNA expression, decrease in cyclin-dependent kinase p21 mRNA expression in Smo-siRNA transfected cells （P 〈 0.05）. Protein expression of cyclin D1 was also downregulated after Smo gene knockdown （P 〈0.05）.The results suggest that Shh signaling plays an important role in RA-FLSs proliferation in a Smo-dependent manner and may contribute to synovial hyperplasia. Targeting Shh signaling may help control joint damage in patients with RA.
