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Christian Prinz - One of the best experts on this subject based on the ideXlab platform.

  • complications of percutaneous transhepatic biliary drainage in patients with dilated and nondilated intrahepatic Bile Ducts
    European Journal of Radiology, 2009
    Co-Authors: A Weber, Jochen Gaa, Bogdan Rosca, P Born, Bruno Neu, Roland M Schmid, Christian Prinz
    Abstract:

    Abstract Percutaneous transhepatic biliary drainage (PTBD) have been described as an effective technique to obtain biliary access. Between January 1996 and December 2006, a total of 419 consecutive patients with endoscopically inaccessible Bile Ducts underwent PTBD. The current retrospective study evaluated success and complication rates of this invasive technique. PTBD was successful in 410/419 patients (97%). The success rate was equal in patients with dilated and nondilated Bile Ducts ( p =0.820). In 39/419 patients (9%) procedure related complications could be observed. Major complications occurred in 17/419 patients (4%). Patients with nondilated intrahepatic Bile Ducts had significantly higher complication rates compared to patients with dilated intrahepatic Bile Ducts (14.5% vs. 6.9%, respectively [ p =0.022]). Procedure related deaths were observed in 3 patients (0.7%). In conclusion, percutaneous transhepatic biliary drainage is an effective procedure in patients with dilated and nondilated intrahepatic Bile Ducts. However, patients with nondilated intrahepatic Bile Ducts showed a higher risk for procedure related complications.

Vincenzo Mazzaferro - One of the best experts on this subject based on the ideXlab platform.

Yasuni Nakanuma - One of the best experts on this subject based on the ideXlab platform.

  • telomere shortening in the damaged small Bile Ducts in primary biliary cirrhosis reflects ongoing cellular senescence
    Hepatology, 2008
    Co-Authors: Motoko Sasaki, Hiroko Ikeda, Junpei Yamaguchi, Satoko Nakada, Yasuni Nakanuma
    Abstract:

    Telomere shortening is a trigger of cellular senescence. Biliary epithelial cells in damaged small Bile Ducts in primary biliary cirrhosis (PBC) show senescent features such as the expression of senescence-associated β-galactosidase and the increased expression of p16INK4a and p21WAF1/Cip1. We investigated whether the telomere shortening is involved in the pathogenesis of biliary cellular senescence in PBC. We analyzed the telomere length of biliary epithelial cells using quantitative fluorescence in situ hybridization in livers taken from the patients with PBC (n = 13) and control livers (n = 13). We also assessed immunohistochemically the prevalence of DNA damage and the expression of p16INK4a and p21WAF1/Cip1. The study showed a significant decrease in telomere length in biliary epithelial cells in the damaged small Bile Ducts and Bile ductules in PBC compared with normal-looking Bile Ducts and Bile ductules in PBC, chronic viral hepatitis, and normal livers (P < 0.01). γH2AX-DNA-damage-foci were detected in biliary epithelial cells in damaged small Bile Ducts and Bile ductules in PBC but were absent in biliary epithelial cells in chronic viral hepatitis and normal livers. The expression of p16INK4a and p21WAF1/Cip1 was increased corresponding to telomere shortening and γH2AX-DNA-damage-foci in the damaged small Bile Ducts in PBC. Conclusion: Telomere shortening and an accumulation of DNA damage coincide with increased expression of p16INK4a and p21WAF1/Cip1 in the damaged Bile Ducts, characterize biliary cellular senescence, and may play a role in the following progressive Bile duct loss in PBC. (HEPATOLOGY 2008.)

  • Fractalkine and CX3CR1 are involved in the recruitment of intraepithelial lymphocytes of intrahepatic Bile Ducts
    Hepatology (Baltimore Md.), 2005
    Co-Authors: Kumiko Isse, Kenichi Harada, Yoh Zen, Takashi Kamihira, Shinji Shimoda, Mine Harada, Yasuni Nakanuma
    Abstract:

    Fractalkine is a chemokine with both chemoattractant and cell-adhesive functions, and in the intestine it is involved with its receptor CX3CR1 in the chemoattraction and recruitment of intraepithelial lymphocytes. We examined the pathophysiological roles of fractalkine and CX3CR1 in normal and diseased Bile Ducts. Expression of fractalkine and CX3CR1 were examined in liver tissues from patients with primary biliary cirrhosis (17 cases) and controls (9 cases of primary sclerosing cholangitis, 10 cases of extrahepatic biliary obstruction, 20 cases of chronic viral hepatitis C, and 18 cases of histologically normal livers). Expression of fractalkine in biliary epithelial cells (BECs) in response to cytokine treatments was examined using a human cholangiocarcinoma cell line (HuCC-T1) and human intrahepatic BEC line. The chemotaxis of CX3CR1-expressing monocytes (THP-1) toward fractalkine was assayed using chemotaxis chambers. Fractalkine messenger RNA/protein were expressed on BECs of normal and diseased Bile Ducts, and their expression was upregulated in injured Bile Ducts of primary biliary cirrhosis. CX3CR1 was expressed on infiltrating mononuclear cells in portal tracts and on CD3+, CD4+, and CD8+ intraepithelial lymphocytes of injured Bile Ducts in primary biliary cirrhosis. Fractalkine messenger RNA expression was upregulated in two cultured BECs on treatment with lipopolysaccharide and Th1-cytokines (interleukin 1β, interferon gamma, and tumor necrosis factor α). THP-1 cells showed chemotaxis toward fractalkine secreted by cultured cells. In conclusion, Th1-cytokine predominance and lipopolysaccharide in the microenvironment of injured Bile Ducts resulting from primary biliary cirrhosis induce the upregulation of fractalkine expression in BECs, followed by the chemoattraction of CX3CR1-expressing mononuclear cells, including CD4+ and CD8+ T cells, and their adhesion to BECs and the accumulation of biliary intraepithelial lymphocytes. (HEPATOLOGY 2005;41:506–516.)

  • increased expression of waf1 in intrahepatic Bile Ducts in primary biliary cirrhosis relates to apoptosis
    Journal of Hepatology, 2001
    Co-Authors: Kenichi Harada, Shinichi Furubo, Satoru Ozaki, Katsushi Hiramatsu, Yoshiko Sudo, Yasuni Nakanuma
    Abstract:

    Abstract Background/Aims : In primary biliary cirrhosis (PBC), the intrahepatic small Bile Ducts are selectively damaged by immune attacks, followed by progressive loss mainly due to apoptosis. Compared to the intercellular signaling such as the CD95/CD95 ligand interaction, little is known about alterations in intracellular cell cycle regulatory proteins and genotoxic damage in this apoptotic process. WAF1 is a potent and reversible inhibitor of cell cycle progression at both the G1 and G2 checkpoint and upregulated WAF1 induces irreversible G1 arrest and apoptosis. Transcriptional activation of the WAF1 gene is induced by the upregulated p53 in response to DNA damage. In this study, the cell cycle regulatory process of apoptosis in PBC was examined with respect to expression of WAF1. Methods : Immunostaining for WAF1 and p53 was performed using 11 liver sections of PBC and 26 control livers. In addition, Ki67, apoptosis (TUNEL-positive), and human telomerase RNA (hTR) were also detected. Results : WAF1 was expressed in the nuclei of several epithelial cells in most damaged Bile Ducts in PBC but infrequently or rarely in controls. Some of these cells were also positive for p53, while the remainder were not. Ki67 immunostaining and TUNEL disclosed that the Bile Ducts in PBC showed increased cell division as well as enhanced apoptosis. Immunostaining of Ki67 and TUNEL staining showed that WAF1-positive cells were not proliferating, while some WAF1-positive cells were undergoing apoptosis. Moreover, the Bile Ducts lacked hTR expression, implying progressive shortening of telomeres during increased cell divisions. Conclusions : It seems possible that in PBC, expression of WAF1 on biliary epithelial cells relates to the apoptosis. p53 may be involved in this upregulation. This may be due to physiological upregulation of WAF1 and p53 in response to genotoxic damage such as oxidative stress associated with cholangitis, suggesting other processes than CD95/CD95 ligand interaction in biliary epithelial apoptosis in PBC.

A Weber - One of the best experts on this subject based on the ideXlab platform.

  • complications of percutaneous transhepatic biliary drainage in patients with dilated and nondilated intrahepatic Bile Ducts
    European Journal of Radiology, 2009
    Co-Authors: A Weber, Jochen Gaa, Bogdan Rosca, P Born, Bruno Neu, Roland M Schmid, Christian Prinz
    Abstract:

    Abstract Percutaneous transhepatic biliary drainage (PTBD) have been described as an effective technique to obtain biliary access. Between January 1996 and December 2006, a total of 419 consecutive patients with endoscopically inaccessible Bile Ducts underwent PTBD. The current retrospective study evaluated success and complication rates of this invasive technique. PTBD was successful in 410/419 patients (97%). The success rate was equal in patients with dilated and nondilated Bile Ducts ( p =0.820). In 39/419 patients (9%) procedure related complications could be observed. Major complications occurred in 17/419 patients (4%). Patients with nondilated intrahepatic Bile Ducts had significantly higher complication rates compared to patients with dilated intrahepatic Bile Ducts (14.5% vs. 6.9%, respectively [ p =0.022]). Procedure related deaths were observed in 3 patients (0.7%). In conclusion, percutaneous transhepatic biliary drainage is an effective procedure in patients with dilated and nondilated intrahepatic Bile Ducts. However, patients with nondilated intrahepatic Bile Ducts showed a higher risk for procedure related complications.

G Cozzi - One of the best experts on this subject based on the ideXlab platform.