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C Ara

Publications and source records attributed to C Ara.

15 recordsLinked to original sources
PubMed2006

Liver pathology and cell proliferation after calcineurin inhibitors and antiproliferative drugs following partial hepatectomy in rats.

Immunosuppressants are the cornerstones of treatment after solid organ transplantation. This study investigated the pathology and cell proliferation following partial hepatectomy (PH) in rats undergoing immunosuppressive treatment. After 1 day, all rats were subjected to 70% PH. Groups A and B (n = 10) received calcineurin inhibitors subcutaneously: either FK506 or cyclosporine (CyA). Groups C and D (n = 10) received antiproliferative drugs: either mycophenolate mofetil (MMF) or sirolimus (SRL) by gavage. A control group (n = 5) received 1 mL of tap water daily. On postoperative day 2, all rats were sacrificed to obtain liver tissue for pathologic examination. Using immunohistochemistry we separately examined the hepatectomy surface and the liver parenchyma. In the parenchyma, the Ki-67 indices were higher in the CyA and FK506 groups and lower in the SRL and MMF groups compared with controls (P < .01). CyA had the highest and MMF the lowest values. On the hepatectomy surface, Ki-67 indices and TGF-alpha expressions were higher in the CyA group and lower in the SRL and MMF groups compared with the control group (P < .01). Slightly higher values in the FK506 group were not significantly different compared with the control group (P > .05). All groups other than FK506 showed prominent cholangiolar epithelial phenotypes compared with the control group. In the CyA and SRL groups, the number of cholangiolar cells was higher (P < .01), and in the MMF group lower than in the control group (P < .01). Among all groups, SRL had the highest values.

Animals↗
PubMed2006

Partial hepatectomy is curative for the localized type of Caroli's disease: a case report and review of the literature.

The case of a 58-year-old woman who was diagnosed with the localized type of Caroli's disease is presented. This disease involves the whole of the left half of the liver. A left hepatectomy was followed by complete resolution of symptoms. The current article suggests that hepatic resection may be aggressively performed in selected patients with the localized form of Caroli's disease.

Caroli Disease↗
PubMed2003

Gliadin and tissue transglutaminase complexes in normal and coeliac duodenal mucosa.

Tissue transglutaminase (tTG) seems to be the target self-antigen for endomysial antibodies in coeliac disease (CD) and to catalyse the critical deamidation of gliadin which strengthens its recognition by HLA-restricted gut-derived T cells. To date, it has not been demonstrated whether gliadin is cross-linked to tTG within the gut wall, a phenomenon known to occur in vitro. We therefore investigated the putative presence of tTG and gliadin complexes directly in duodenal mucosa. The immunoprecipitation and Western blotting experiments were performed on mucosal biopsies obtained from untreated, treated CD patients and biopsied controls, by using either anti-tTG or anti-gliadin antibodies, in both denaturating/reducing or nondenaturating/nonreducing conditions. A subset of experiments was performed by using anti-tTG antibodies purified by affinity chromatography from sera of untreated coeliac patients. The localization of tTG and gliadin was studied by immunofluorescence at confocal laser microscopy on seriate sections of diseased and normal duodenal mucosa by using the same antibodies of the coimmunoprecipitation section. The amounts of tTG and gliadin coimmunoprecipitated with anti-tTG monoclonal antibody in untreated CD mucosa were significantly increased compared to those of the other two groups. When performing the experiments in nondenaturating/nonreducing conditions, a high molecular weight band formed by both molecules, was evidenciated. Also the anti-tTG antibodies purified from patients' sera turned out to be able to coimmunoprecipitate the two molecules. The analysis by confocal microscopy showed that tTG colocalizes with gliadin at the epithelial and subepithelial levels in active CD, and only in the lamina propria of the villi in normal mucosa. Our findings firstly demonstrated that gliadin was directly bound to tTG in duodenal mucosa of coeliacs and controls, and the ability of circulating tTG-autoantibodies to recognize and immunoprecipitate the tTG-gliadin complexes.

Adult↗
PubMed2002

Influence of a low background radiation environment on biochemical and biological responses in V79 cells.

We present the results of an experiment aimed at comparing the effects of different background radiation environments on metabolism and responses to gamma-rays and cycloheximide of cultured mammalian cells. Chinese hamster V79 cells were maintained in exponential growth in parallel for up to 9 months at the Istituto Superiore di Sanità (ISS) and at the INFN-Gran Sasso underground Laboratory (LNGS) where exposure due to gamma-rays and to radon was reduced by factors of about 70 and 25, respectively. After 9 months the cells grown at the LNGS (cumulative gamma dose about 30 microGy, average radon concentration around 5 Bq/m(3)), compared to the cells grown at the ISS (cumulative gamma-ray dose about 2 mGy, average radon concentration around 120 Bq/m(3)), exhibited i). a significant increase of the cell density at confluence, ii). a significantly higher capacity to scavenge organic and inorganic hydroperoxides but a reduced scavenging capacity towards superoxide anions and iii). an increase in both the basal hprt mutation frequency and sensitivity to the mutagenic effect of gamma-rays. The cells grown at the LNGS also showed a greater apoptotic sensitivity starting at the third month of culture, that was no longer detected after 9 months. Overall, these data suggest a role of background ionizing radiation in determining an adaptive response, although they cannot be considered conclusive.

Air Pollution, Indoor↗
PubMed2002

Retinoic acid modulates gap junctional intercellular communication in hepatocytes and hepatoma cells.

Gap junctional communication permits the direct exchange of small molecules and ions and has been implicated in tissue homeostasis/metabolite exchange. The lack of gap junctional intercellular communication (GJIC) plays important roles in the promotion and progression of carcinogenesis. In the present study, we demonstrate that treatment of human hepatoma Hep G2 cells with retinoic acid (RA) results in increased amounts and phosphorylation of connexins, their stabilisation in plasma membrane plaques and enhanced GJIC. In cultured fetal hepatocytes, which represent a non-transformed, proliferating and incompletely differentiated liver system, the effects of RA are limited to the establishment of connexin in areas of cell-cell contact and the improvement of GJIC. This suggests that modulation of cell-cell channel communication by RA occurs differently in these two experimental models: while RA is able to revert cell transformation in Hep G2 cells, in fetal hepatocytes it may induce the expression of a more differentiated phenotype.

Animals↗
PubMed2001

Morphologic changes in breast biopsies after duct endoscopy.

Duct endoscopy is a recent technique used for a direct view of the breast ductal system. The aim of this study is to determine any morphological changes in breast tissue attributable to low-pressure irrigation with saline solution that the technique requires. A total of 26 breast biopsies from patients who underwent ductal endoscopy before surgery were compared with 26 breast specimens from the retroareolar region. Breast specimens from duct endoscopy showed more frequent epithelial detachment (73%), epithelial loss (35%), periductal clefts (77%), stromal disaggregation (46%) and displacement of epithelial cells into the stroma (27%) than the control group in which epithelial detachment was seen in 4% of patients, periductal clefts in 15%, and stromal disaggregation in 15%. Epithelial loss and epithelial displacement where not seen in the control group. Although low-pressure fluid perfusion used for duct endoscopy induced morphological changes in breast tissue, these can easily be distinguished from malignancy, and are most likely to occur as the result of duct rupture.

Journal Article↗
PubMed2001

Randomised clinical trial of two bypass operations for unresectable cancer of the pancreatic head.

OBJECTIVE: To compare two different types of prophylactic gastric bypass in patients with cancer of the pancreatic head who were not suitable for curative resection. DESIGN: Prospective study. SETTING: University hospital, Turkey. SUBJECTS: 44 patients with unresectable cancer of the pancreatic head without duodenal obstruction who presented between May 1995 and June 2000 who were randomised into 2 groups. INTERVENTIONS: 22 patients had an antecolic, isoperistaltic gastrojejunostomy, jejunojejunostomy, and hepaticojejunostomy after cholecystectomy. The remaining 22 had a hepaticojejunostomy and antecolic, antiperistaltic gastrojejunostomy procedure after cholecystectomy. MAIN OUTCOME MEASURES: Mortality, morbidity, postoperative course, and survival. RESULTS: There were no significant differences between the groups in the incidence of postoperative complications, time until restoration of oral diet, relaparotomy rate, late upper gastrointestinal bleeding, mortality, duration of hospital stay, and survival. The isoperistaltic operation took significantly longer than the antiperistaltic operation (p < 0.001) and there was less delayed gastric emptying in the antiperistaltic group but not significantly so. Both operations caused a significant lengthening in the postoperative gastric emptying time (p = 0.04 and p = 0.01, respectively). CONCLUSION: Both procedures are suitable for patients with unresectable carcinoma of the pancreatic head without impending duodenal obstruction. There was a trend towards better clinical results with the isoperistaltic procedure.

Adult↗
PubMed2001

Lack of correlation between clinical characteristics and serum soluble Fas ligand levels in patients with multiple myeloma.

Multiple myeloma is characterized by the accumulation of malignant plasma cells in the bone marrow and rarely cured by chemotherapy. Villunger et al. showed that the neoplastic plasma cells express Fas ligand (FasL), which transmits a signal of apoptosis upon ligation to Fas, and suggested that the FasL suppresses the T-cells activated against malignant cells, resulting in escape from tumour immunity. We examined serum soluble FasL (sFasL) levels in 35 multiple myeloma patients to evaluate the correlation between sFasL levels and clinical characteristics. The serum sFasL levels were not affected by the disease status, serum monoclonal protein levels, or other prognostic factors. We could not determine whether the expression of FasL is involved in the poor clinical course of the disease.

Adult↗
PubMed1998

The effect of retinoic acid on the re-establishment of differentiated hepatocyte phenotype in primary culture.

The usefulness of cultured hepatocytes is limited by the gradual loss of their typical physiological functions that occurs in vitro, mainly due to the absence of microenviromental conditions found in vivo. In this study we describe the effect of retinoic acid on the re-establishment of morphological characteristics and on the reorganization of the cytoskeletal network in cultured rat hepatocytes. Results obtained demonstrate that retinoic acid can influence hepatocyte differentiation, as regards the recovery of cell polarity, polyhedric shape and reformation of bile canaliculi and junctional complexes. The main target of this action appears to be the cytoarchitecture of cytoskeletal components, particularly cytokeratin filaments, which regain the configuration present in intact liver. The reorganization of the intermediate filaments does not seem to be dependent on the induction of higher levels of cytokeratin proteins, but rather appears to be due to post-translational regulation. The effect of retinoic acid on the cytoskeletal organization could determine the stabilization of intercellular contacts by means of junctions, leading to the appearance of morpho-functional characteristics typical of well-differentiated hepatocytes.

Animals↗
PubMedDate not supplied

Proton magnetic resonance spectroscopy findings of a sacrococcygeal schwannoma.

Schwannoma is tumor of peripheral nerves, originating from Schwann cells. It is a rare nerve sheath tumor, which frequently occurs in the intracranial acoustic nerve and spinal nerves. We report on a 28-year-old woman who suffered from a large pelvic mass that was diagnosed to be sacrococcygeal schwannoma. The features of proton magnetic resonance spectroscopy (MRS) study are discussed. The magnetic resonance imaging instrument was a 1.5 T, Gyroscan Intera with a body coil as a radiofrequency transmitter and a signal receiver. T2-weighted images were obtained under the following conditions-turbo spin echo (TSE) T2: turbo spin echo repeat time (TR) = 4500 msec, echo time (TE) = 96 msec. Single voxel MRS was performed by the point-resolved spectroscopy technique with a long TE (136 msec). MRS measurement was performed on two different parts of the tumor. As well as strongly elevated choline and lipid signals, the tumor spectrum showed increased N-acetylaspartate resonances. MRS can be used effectively in the preoperative diagnosis of retroperitoneal and pelvic masses, which demonstrate unusual clinical features.

Adult↗
PubMedDate not supplied

Growth inhibition and induction of specific hepatic phenotype expression by retinoic acid in HEPG2 cells.

Retinoic acid, the active metabolite of vitamin A, plays a role in the growth and differentiation of a variety of normal and malignant cells. In response to 5 microM retinoic acid the human hepatoma-derived cell line HepG2 underwent significant growth inhibition (not associated with cell death), which reached a level of 80% in comparison with controls, after 12 days of continuous treatment. Retinoic acid also induced morphological changes in these cells, in particular the development of canalicular-like structures, indicating progression to a more differentiated phenotype. In addition, a reduced expression of alpha-fetoprotein was found. We suggest that our results may be important for the design of novel therapeutic approaches using RA for the treatment of liver tumors.

Cell Division↗