Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.

Adult↗

PubMedDate not supplied

Residual contrast medium in the cortex of the kidney around an infected renal cyst on CT: case report.

We present a case of a patient with an infected renal cyst. Delayed computed tomography showed residual contrast medium in the cortex of the kidney around it. Delayed computed tomography might be useful to identify an infected renal cyst.

Contrast Media↗

PubMedDate not supplied

Astrocytic contributions to blood-brain barrier (BBB) formation by endothelial cells: a possible use of aortic endothelial cell for in vitro BBB model.

Astrocytic contribution of endothelial cell monolayer permeability was examined in two blood-brain barrier (BBB) models, using the coculture in a double chamber system: rat astrocytes and bovine aortic endothelial cells (BAECs) or bovine brain endothelial cells (BBECs). In system 1, where astrocytes were separated from endothelial cells, a 40% reduction in L-glucose permeability of the BBEC monolayer, but not the BAEC monolayer, was observed by cocultivation with astrocytes. Although several passages of BBEC in culture elicited morphological transformation from spindle-shapes to cobblestone-like features, the passaged BBECs remained responsive to astrocytes in coculture in system 1 (37% reduction of the L-glucose permeability). By contrast, in system 2, where respective endothelial cells and astrocytes layered on the upper and lower surfaces of a membrane, the permeability of both BAEC and BBEC monolayers was reduced by cocultivation with astrocytes (75% reduction for BAEC and 40% reduction for BBEC). BAECs in this contiguous coculture (system 2) with astrocytes showed numerous tight junction-like structures characteristic of the BBB in vivo. These results suggest that primary cultured BBECs, which had been primed by astrocytes in vivo, retain a higher sensitivity to astrocytes possibly through an astrocytic soluble factor (s) to exhibit BBB-specific phenotypes, and that even BAEC from extra-neural tissues, when cultured with astrocytes in close proximity in vitro, may acquire the similar phenotypes and serve for an extensive use of BBB model in vitro.

Animals↗

PubMedDate not supplied

Detection of Grb-2-related adaptor protein gene (GRAP) and peptide molecule in salivary glands of MRL/lpr mice and patients with Sjögren's syndrome.

The pathogenesis of Sjögren's syndrome (SS) is poorly understood. In this study we used an in-house mouse spleen cDNA microarray to analyse genes in spleens from MRL/lpr (an SS mouse model) mice. We have previously demonstrated that GRAP genes were up-regulated in salivary glands of the same mice. The microarray analysis showed that seven out of 2304 genes were highly expressed in spleens from the MRL/lpr mice, one of which was the GRAP gene. In other words, the GRAP gene is highly expressed in the salivary glands and spleen of MRL/lpr mice. We also carried out immunohistochemical studies. Mouse and human Grb-2-related adaptor protein (GRAP) antigens were expressed on ductal cells and infiltrating lymphocytes in salivary glands of MRL/lpr mice and SS patients, but only weakly in controls (MRL/+ mice and individuals with salivary cysts). These results suggest that the GRAP gene might have a role in the pathogenesis of SS.

Adaptor Proteins, Signal Transducing↗

PubMedDate not supplied

Phenotypical characteristics of undifferentiated carcinoma of the pancreas: a comparison with pancreatic ductal adenocarcinoma and relevance of E-cadherin, alpha catenin and beta catenin expression.

The characteristics of undifferentiated (anaplastic) carcinoma (UC) of the pancreas were analysed and compared with those of poorly differentiated adenocarcinoma (PA). Eight cases of UC of the pancreas were evaluated by clinicopathological and immunohistochemical methods and compared with 20 cases of PA. Large size of the tumor, local invasion and lymph node metastasis were frequently seen in UC, leading to a significantly worse prognosis compared to that of PA (p=0.022). Immunohistochemically, E-cadherin expression was completely lost in 7/8 UC cases, whereas half the PA cases revealed a strong reactivity for E-cadherin. alpha- and beta-catenin expressions tended to be impaired in UC compared with PA. The results suggest that the altered expression of adhesion molecules is correlated with dedifferentiated change and is contributory to its aggressive biological behaviour.

Adenocarcinoma↗

PubMedDate not supplied

Suppressive effect of sesamin against 7,12-dimethylbenz[a]-anthracene induced rat mammary carcinogenesis.

The effects of dietary supplementation of sesamin on 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary carcinogenesis in female Sprague-Dawley rats were studied. Experimental diets containing 0.2% sesamin (an equiweight mixture of sesamin and episesamin) or 0.2% alpha-tocopheryl acetate were given to rats starting 1 week before intragastric administration of DMBA (10 mg/rat). Sesamin significantly (p less than 0.05) reduced the cumulative number of palpable mammary cancers by 36% at 12 weeks post-DMBA administration compared with animals on a control diet. Alpha-tocopheryl acetate inhibited both the incidence and the cumulative number of mammary tumors by 20% and 45%, respectively. Concentrations of lipid peroxides in plasma, liver and tumors were all decreased in both sesamin and alpha-tocopheryl acetate groups. The activity of peripheral blood mononuclear cells (PBMC) increased in rats fed sesamin (140 to 150% of the control and alpha-tocopheryl acetate groups). Fatty acid compositions of plasma, liver and tumor phosphatidylcholine showed a decreased tendency of the metabolism of linoleic acid to arachidonic acid and hence of the plasma concentration of prostaglandin E2 in the sesamin group. The inhibitory effect of sesamin on DMBA-induced mammary carcinogenesis may be ascribed, at least in part, to immunopotentiation and increased antioxidative activity.

9,10-Dimethyl-1,2-benzanthracene↗

PubMedDate not supplied

Effect of dietary fat and cholesterol on dimethylbenz[a]-anthracene-induced mammary tumorigenesis in Sprague-Dawley rats.

The effect of dietary fats and cholesterol on dimethylbenz[a]-anthracene-induced mammary tumorigenesis was studied in female Sprague-Dawley rats. When the dietary fat source (at the 5% level) was palm oil (saturated fat) or corn oil (unsaturated fat), dietary cholesterol at the 0.2% level increased the tumor number of rats fed corn oil, but not those fed palm oil. Perilla oil (rich in alpha-linolenic acid) reduced tumor development as compared with safflower oil (rich in linoleic acid), but again dietary cholesterol at the 0.5% level diminished the favorable effect of n-3 polyunsaturated fatty acid (PUFA). The adverse effect of cholesterol was also observed in the n-6 PUFA fat. The promotive effect of dietary cholesterol was not necessarily associated with the change in the production of prostaglandin E2 by the tumor tissue or in the immunopotentiation. These results at least stress that the contrasting effects of dietary fats should be carefully evaluated whether cholesterol is present simultaneously or not.

9,10-Dimethyl-1,2-benzanthracene↗

PubMedDate not supplied

Retrovirus-mediated gene therapy for hepatocellular carcinoma: selective and enhanced suicide gene expression regulated by human alpha-fetoprotein enhancer directly linked to its promoter.

We have previously reported that a retrovirus vector (LNAF0.3TK) carrying a herpes simplex virus thymidine kinase gene regulated only by the 0.3-kb human alpha-fetoprotein (AFP) promoter provides ganciclovir (GCV)-mediated cytotoxicity in high AFP-producing human hepatoma cells but not in low AFP-producing cells. In the present study, a retrovirus vector (LNAF0.3(E+)TK), in which herpes simplex virus thymidine kinase gene expression is under the control of a human AFP enhancer directly linked to its promoter, was constructed and compared with LNAF0.3(E+)TK. In the intermediate and low AFP-producing human hepatoma cells PLC/PRF/5 and huH1/cl.2, respectively, as well as in the high AFP-producing human hepatoma cells (HepG2), LNAF0.3(E+)TK sensitized these cells to GCV in vitro but did not affect cell growth in nonhepatoma cells (HeLa). In an animal model using athymic mice harboring PLC/PRF/5 cells, GCV treatment resulted in more pronounced growth inhibition in the LNAF0.3(E+)TK virus-infected cells than in the LNAF0.3(E+)TK virus-infected cells. These results indicate that the human AFP enhancer that is directly linked to its promoter involves selective and enhanced tumoricidal activity in gene therapy for hepatocellular carcinoma.

Animals↗