Preoperative MRCP to detect choledocholithiasis in acute calculous cholecystitis.

PURPOSE: There are risks of common bile duct (CBD) stones in acute cholecystitis, and there is a move among surgeons to identify choledocholithiasis before surgery. Magnetic resonance cholangiopancreaticography (MRCP) has the potential to accurately detect choledocholithiasis in patients with acute cholecystitis. The aim of this study was to evaluate the predictive values of MRCP and elevated biochemical predictors for choledocholithiasis in patients with acute cholecystitis. METHODS: Between September 2006 and August 2008, of 84 patients with acute cholecystitis based on the diagnosis criteria of the Tokyo guidelines, 57 had MRCP preoperatively. The predictive values of six biochemical predictors for choledocholithiasis were also evaluated. RESULTS: Of the 57 patients, seven (12.28%) had choledocholithiasis, of whom three had CBD stones in nondilated ducts. The smallest stone detected in a dilated CBD and nondilated duct was 3.19 and 4.55 mm in diameter, respectively. None of our patients whose MRCP showed a clear CBD returned with symptomatic choledocholithiasis during the follow-up period. All biochemical predictors and CBD diameter had limited positive predictive values. CONCLUSIONS: Magnetic resonance cholangiopancreaticography is a reliable evaluation technique for the detection of choledocholithiasis. It reduces the misdiagnosis of retained choledocholithiasis with normal biochemical predictors and prevents the risk of overlooking choledocholithiasis. No single predictor or combined markers have been found to be reliable for including/excluding the presence of choledocholithiasis.

Plectin deficiency on cytoskeletal disorganization and transformation of human liver cells in vitro.

Plectin is a versatile cytoplasmic cross-linking protein that connects intermediate filaments to microfilaments, microtubules, and membrane adhesion sites. The cross-linking functions of plectin help organize the cytoskeleton into a stable meshwork important for maintaining uniformity in cell size and shape. As cells of hepatocellular carcinoma are morphologically different from normal human hepatocytes, we hypothesized that altered plectin expression and cytoskeletal organization underlies this pleomorphic transformation. To test this hypothesis, we analyzed expression levels and organization of all cytoskeletal elements, including intermediate filaments, microfilaments, and microtubules, after plectin knockdown in human Chang liver cells. We found that expression of cytokeratin 18, but not actin or tubulin, was downregulated by suppression of plectin protein. Furthermore, cytokeratin networks were partially collapsed and actin-rich stress fibers were increased. The organization of microtubule networks, by contrast, was unaltered. These findings support our hypothesis that, via effects on cytoskeletal organization, plectin deficiency might play an important role in the transformation of human liver cells.

Assessment of common bile duct using laparoscopic ultrasound during laparoscopic cholecystectomy.

BACKGROUND: Several reports have shown that laparoscopic ultrasound (LUS) examination of the bile duct is promising and suggest it as a primary method for bile duct imaging during laparoscopic cholecystectomy (LC). This study was designed to evaluate the feasibility of LUS during LC, and the occurrence rate of common bile duct (CBD) stones during LC. MATERIALS AND METHODS: One hundred and fifteen consecutive patients with gallstones were enrolled into this study. LUS was used to assess the CBD routinely during LC, which was successfully performed in 112 cases. Choledocholithiasis was rated before LC as being of low, intermediate, or high probability on the basis of clinical, laboratory, and/or imaging findings (Cotton criteria). Duct calculi were defined as echogenic material within the CBD, which cast discrete acoustic shadows. Sludge was defined as mobile or floating low-amplitude echogenic material without discrete acoustic shadowing. RESULTS: The CBD could be evaluated in 112 of 115 LC (97.4%) patients (72 females and 40 males). The mean age was 54+/-16 years old. The occurrence rate of CBD stones in the low-risk group was 7%, that in the intermediate group was 36.4%, and the high-risk group was 78.9%. The overall incidence of CBD stones was 25.0%. CONCLUSIONS: With increasing experience, LUS can become the routine method for evaluating the bile duct during LC. A more aggressive preoperative evaluation of CBD is mandated in the intermediate and high-risk groups of patients suspected of having CBD stones.

Degradation of plectin with modulation of cytokeratin 18 in human liver cells during staurosporine-induced apoptosis.

BACKGROUND: Hepatoma cells are morphologically different from those of the normal liver. Intermediate filaments (IFs) are important in building the cellular architecture and maintaining the outline of cells. Plectin is a cross-linking protein that organizes the cytoskeleton into a stable meshwork, which can maintain the uniform size and shape of hepatocytes. Apoptosis might be the most possible pathway for creating plectin deficiency in the in vivo state. MATERIALS AND METHODS: Apoptosis was induced by staurosporine (STS) treatment in liver cells. The protein expression of cytokeratin 18 (CK18) and plectin as well as the morphology of the liver cells and the distribution of CK18 and plectin in the cells was studied after STS treatment. RESULTS: Plectin was cleaved in the liver cells during apoptosis and CK18 was modulated. Morphological changes were observed in the liver cells. CONCLUSION: By affecting the organization of IFs, plectin might play an important role in the pleomorphism of hepatoma cells and even the tumorigenesis of hepatoma.

Possible relation between histone 3 and cytokeratin 18 in human hepatocellular carcinoma.

BACKGROUND: Previously we found some low molecular weight proteins identified as histone in hepatocelluar carcinoma. Our objective was to clarify whether the coimmunoprecipitation of histone and cytokeratin 18 was an artifact or not. MATERIALS AND METHODS: Histone 3 and cytokeratin 18 were investigated in three cases of human hepatocellular carcinoma and one case of normal liver tissue. Nuclei of the tissues were isolated; the proteins inside the nuclei were analyzed by Western blot. RESULTS: The results revealed histone was co-immunoprecipitated with cytokeratin 18 in hepatocellular carcinoma. It was speculated that modulation of the cytoskeleton in human hepatocellular carcinoma might disturb the organization of the nucleoskeleton. The unstable nucleoskeleton might further cause instability and fragility of nuclei, thus possibly exposing the histone and co-immunoprecipitating it with cytokeratin 18. CONCLUSION: The evidence might indicate that expression of histone 3 was highly related to modulation of cytokeratin 18 and might play an important role in tumorigenesis of hepatocellular carcinoma.

The influence of plectin deficiency on stability of cytokeratin18 in hepatocellular carcinoma.

Intermediate filaments are important in building the cellular architecture. Previously we found cytokeratin18 was modulated in human hepatocellular carcinoma. Plectin is a cross-linking protein that organizes the cytoskeleton into a stable meshwork, which can maintain the uniform size and shape of hepatocytes. Because the cells of hepatocellular carcinoma were morphologically different from the hepatocytes, we speculated that expression of plectin and organization of intermediate filament might play roles in the pleomorphism of hepatocellular carcinoma cells. In this paper, we studied the plectin expression of hepatocellular carcinoma and liver tissues by immunohistochemistry and immunoblot. The results revealed that plectin was deficient and cytokeratin18 was modulated in hepatocellular carcinoma. Furthermore, we knockdown the plectin mRNA in Chang cells, the result revealed the plectin was deficient and the organization of cytokeratin18 was altered. Conclusively, this study offers a hypothesis that plectin deficient might play an important role in the tumorigenesis of hepatocellular carcinoma.