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D Wendum

Publications and source records attributed to D Wendum.

At least 19 recordsLinked to original sources
PubMed2006

Ciliated hepatic foregut cyst with extensive squamous metaplasia: report of a case.

Ciliated hepatic foregut cysts (CHFC) are rare cystic lesions of the liver composed of a ciliated pseudostratified columnar epithelium with mucous cells, connective tissue, and smooth muscles bundles. We report the first case of CHFC with extensive squamous metaplasia without dysplasia or carcinoma. A unilocular, avascular, hypoechoic 60-mm liver lesion located in segment IV was detected by ultrasonography in a 31-year-old woman. The cyst was surgically removed and was lined mainly by a regular squamous epithelium without keratin formation. After extensive sampling, a ciliated pseudostratified columnar epithelium with some alcian blue-positive goblet cells was identified. The lesion was totally examined and there was no epithelial dysplasia or carcinoma. Squamous epithelium is very rare in hepatic foregut cysts and may degenerate into squamous carcinoma. Squamous epithelium is also described in biliary cysts. When squamous epithelium is identified in a liver cyst, an extensive sampling is recommended to identify possible foci of squamous carcinoma and to classify more precisely the histological type of the lesion. Because some cases of squamous carcinoma have been described in CHFC, surgical removal of the lesion may be more appropriate than close follow-up or sclerosing therapy.

Adult↗
PubMed2005

HHV-6-related acute liver failure in two immunocompetent adults: favourable outcome after liver transplantation and/or ganciclovir therapy.

Fulminant hepatitis of unknown origin remain a significant cause of mortality, for which liver transplantation is often considered as the only therapeutic option. In retrospective studies, human herpesvirus 6 (HHV-6) infections have been associated with such diseases, but the diagnosis of HHV-6 infection of the liver is rarely established during the acute phase of liver failure. Using real-time polymerase chain reaction (PCR), we diagnosed two cases of severe acute liver failure (ALF) related to HHV-6 occurring in immunocompetent young adults. Both cases had a favourable outcome, one after valganciclovir therapy, one after liver transplantation associated with ganciclovir. Viral origin was evidenced in each case by the detection of high amounts of HHV-6 DNA in liver tissue by the PCR assay. The decrease of intrahepatic viral load after therapeutic intervention was also monitored by quantitative PCR and paralleled in the two cases the clinical improvement. Diagnosis of HHV-6 infection must be systematically evoked in case of unexplained ALF, since it might lead to specific therapeutic interventions, in addition of liver transplantation.

Administration, Oral↗
PubMed2005

Insulin resistance is a cause of steatosis and fibrosis progression in chronic hepatitis C.

BACKGROUND: Insulin resistance is a frequent feature of chronic hepatitis C. Whether insulin resistance could be the cause or consequence of steatosis and fibrosis is unknown. The ability of HCV genotype 3 to promote steatosis by itself provides an unique opportunity to answer this question. AIMS: The aim of the present study was to assess the relationships between insulin resistance, steatosis, and fibrosis according to genotype in 141 non-diabetic patients with biopsy proven non-cirrhotic chronic hepatitis C. METHODS: All patients had fasting serum glycaemia and insulinaemia measurements. Insulin resistance was evaluated using the homeostasis model assessment (HOMA IR) method. Liver steatosis was determined according to hepatitis C virus genotype (1 or 3). Logistic regression and multivariate regression analysis were used to identify variables independently associated with insulin resistance, fatty liver, and fibrosis. RESULTS: Although steatosis and fibrosis were more severe in genotype 3 patients, median HOMA IR was significantly higher in patients with genotype 1 related steatosis than in those with genotype 3 related steatosis (2.1 v 1; p = 0.001). Independent risk factors for steatosis were insulin resistance in genotype 1 patients (p = 0.001) and viral load in genotype 3 patients (p = 0.003). Among genotype 1 patients, independent parameters associated with insulin resistance were age (p = 0.04) and steatosis (p = 0.004). Steatosis was associated with more severe fibrosis whatever the genotype (p = 0.002). Among genotype 1 patients, although there was a significant relationship between circulating insulin level and fibrosis stage (p = 0.006), only steatosis and inflammatory score were independently associated with fibrosis. CONCLUSION: This study shows that insulin resistance is the cause rather than the consequence of steatosis and fibrosis in genotype 1 patients and that increased circulating insulin is a risk factor for fibrosis through insulin resistance induced steatosis.

Adult↗
PubMed2004

Significance of hepatitis C virus coinfection with persistently normal alanine aminotransferase levels in HIV-1-infected patients.

OBJECTIVES: To assess the prevalence of chronic hepatitis C virus (HCV) infection with persistently normal alanine aminotransferase (ALT) levels in HIV-1-infected patients, together with its clinical, biological and histological characteristics and predictive factors. METHODS: We retrospectively studied all HCV/HIV-coinfected patients treated in our Infectious Diseases Department, for whom data on both HIV and HCV infection were available. We compared the demographic characteristics and parameters of HIV and HCV infection between cases, defined by persistently normal ALT levels (<45 IU/L) and detectable serum HCV-RNA (determined by PCR), and controls with high ALT levels and HCV PCR positivity during the previous 3 years. RESULTS: Among the 815 HIV-infected patients assessed for this study, 179 (22%) were HCV-coinfected, of whom 155 were eligible for this analysis. Of these 155 HCV-coinfected patients, 137 (88%) were HCV-PCR-positive, of whom 39 (28.5%) had persistently normal ALT levels (cases) and 98 (71.5%) had high ALT levels (controls). Relative to controls, cases had a significantly lower fibrosis score and a lower fibrosis progression rate (2.2 vs. 1.3, P=0.004; 0.3 vs. 0.2, P=0.006, respectively). Three factors associated with persistently normal ALT levels were identified, namely: HBsAg negativity (P=0.003), HCV genotype 4 (P=0.01) and female sex (P=0.05). CONCLUSION: Persistently normal ALT levels may be considered as a marker of slow HCV disease progression in HIV-coinfected patients, with significantly less severe hepatic lesions.

Adult↗
PubMed2003

Cyclooxygenase-2 is expressed frequently and early in Barrett's oesophagus and associated adenocarcinoma.

AIMS: To establish the prevalence of cyclooxygenase-2 (COX-2) expression in a large series of resected Barrett's adenocarcinoma and associated preneoplastic lesions and to correlate this expression with clinicopathological data and prognosis. METHODS: COX-2 expression was assessed by immunohistochemistry in resected surgical specimens of 66 Barrett's adenocarcinomas and 32 cases of Barrett's mucosa (with dysplasia in 17 cases). RESULTS: Epithelial expression of COX-2 protein was increased in Barrett's mucosa compared with normal oesophagus. Epithelial expression of COX-2 was found in 91% of Barrett's specialized mucosa negative for dysplasia, 94% of Barrett's mucosa with dysplasia, and 97% of Barrett's adenocarcinoma. COX-2 expression was significantly higher in the well-differentiated adenocarcinomas when compared with the poorly differentiated tumours. There was no significant correlation between COX-2 expression and the other pathological features of the tumours. Survival analysis showed no significant prognostic value for COX-2. CONCLUSION: Our results confirm up-regulation of COX-2 in Barrett's oesophagus-metaplastic and dysplastic-and in Barrett's adenocarcinoma. Increased COX-2 expression did not differ during the progression from Barrett's oesophagus negative for dysplasia to Barrett's adenocarcinoma and is related to adenocarcinoma whose histology is well differentiated. This suggests that enhanced expression of COX-2 may occur early during Barrett's-associated neoplastic transformation.

Adenocarcinoma↗
PubMed2003

Immunohistochemical analysis of adenocarcinoma of the small intestine: a tissue microarray study.

BACKGROUND: Primary adenocarcinomas of the small intestine are rare, and the genetic mechanisms involved in their carcinogenesis remain unclear. AIM: To examine the expression of candidate proteins in small intestinal adenocarcinomas by immunohistochemistry performed on tissue microarrays (TMAs). METHODS: Twenty seven primary sporadic small intestinal adenocarcinomas were analysed. The TMA technique was validated by comparing immunohistochemical labelling of hMLH1 and hMSH2 on TMAs and the tissue sections they derived from. The expression of Smad4, hMSH6, beta catenin, and p53 was investigated and results compared with those obtained in 14 malignant ampullary tumours. RESULTS: TMA technology with threefold redundancy adequately represented the immunohistochemical pattern of small intestinal adenocarcinomas. Loss of hMLH1 expression, but not hMSH2 or hMSH6, was seen in two of 27 small intestinal adenocarcinomas. All ampullary tumours showed nuclear staining for hMSH2 and hMSH6. One case showed lack of immunostaining for hMLH1. Smad4 expression was absent in five small intestinal adenocarcinomas and two ampullary tumours. Overexpression of p53 was detected in the nuclei of 14 of the 27 small intestinal adenocarcinomas, and five of the 14 ampullary tumours. Nuclear or cytoplasmic expression of beta catenin was present in all specimens. CONCLUSION: Inactivation of the SMAD4/DPC4 gene seems to be involved in small intestinal adenocarcinoma tumorigenesis. Overexpression of p53 and abnormal expression of beta catenin are two common events, unlike the loss of expression of the DNA mismatch repair proteins (hMLH1, hMSH2, and hMSH6). The carcinogenetic process appears to be similar in small intestinal adenocarcinomas and malignant ampullary tumours.

Adenocarcinoma↗
PubMed2001

Impact of early-untreated HIV infection on chronic hepatitis C in intravenous drug users: a case-control study.

OBJECTIVE: The impact of early-untreated HIV infection on chronic hepatitis C was determined in a case-control study, aimed at limiting factors associated with the progression of immunodeficiency. METHODS: HIV-infected patients attending for a medical examination during 1995-1996 were systematically screened for: previous intravenous drug use without other HIV or Hepatitis C virus (HCV) risk factor, CD4 cell count > 200/microl, no AIDS, no antiretroviral treatment, positive anti-HCV antibody, negative hepatitis B surface antigen, abnormal aminotransferase activity. Thirty-eight consecutive eligible HIV-infected patients (cases) were included. Thirty-eight HCV-infected patients without HIV infection whose unique risk factor was intravenous drug use (controls) were paired to cases according to age, sex, and duration of HCV infection. RESULTS: Cases and controls had similar ages, sex ratios, duration of HCV infection, and alcohol intake. They were infected predominantly by genotypes 1 and 3. Viraemia was higher in cases than in controls. METAVIR histological scores of activity and fibrosis in cases versus controls were 2.2 +/- 0.8 versus 1.6 +/- 0.7 (P = 0.0008) and 1.8 +/- 1 versus 1.5 +/- 0.8 (P = 0.06), respectively. The percentage of cirrhosis was higher in cases, without reaching statistical difference. The progression rate of fibrosis was higher in cases. Age at contamination and METAVIR activity score were significantly associated with the progression of fibrosis in cases. CONCLUSION: Early-untreated HIV infection is associated with higher HCV viraemia and more severe liver injury in intravenous drug users with chronic hepatitis C.

Adult↗
PubMed2001

Hepatic stellate cell proliferation is an early platelet-derived growth factor-mediated cellular event in rat cholestatic liver injury.

SUMMARY: After liver injury, hepatic stellate cells (HSC) undergo a pleiotropic response termed "activation" that also occurs in culture models and ultimately leads to the conversion of HSC into myofibroblasts expressing smooth muscle alpha-actin (alpha-SMA). The onset of HSC proliferation in primary culture coincides with the induction of platelet-derived growth factor receptor-beta (PDGFR-beta) expression, while platelet-derived growth factor (PDGF) is the most potent mitogen for culture-activated HSC. Yet, the mechanisms and the stage of activation required for HSC proliferation in the intact liver are still uncertain. In the present study, we analyzed the proliferative response of HSC to rat cholestatic liver injury and the role of PDGF in this response. After in vivo incorporation of bromodeoxyuridine (BrdU), pure vitamin A-containing HSC were isolated at different time points after bile duct ligation (BDL) or sham operation and were analyzed by means of flow cytometry. The induction of HSC proliferation, as ascertained by BrdU incorporation, occurred between 24 and 48 hours and reached a plateau as soon as 48 hours after BDL. Flow cytometry and immunoblot analyses of HSC indicated that the induction of proliferation in HSC coincided with the up-regulation of PDGFR-beta protein on their surface but preceded that of alpha-SMA. A dose-dependent inhibition of PDGF-BB-induced HSC proliferation by STI571, a PDGF receptor tyrosine kinase inhibitor, was documented in vitro. Daily intraperitoneal injections of STI571 (20 mg/kg) caused a 60% reduction in BrdU positive isolated HSC and in the amount of desmin-immunoreactive sinusoidal cells on liver tissue sections in 48-hour bile duct-ligated rats. These results indicate that cholestatic liver injury elicits an early proliferative response in HSC that is mainly mediated by PDGF, and which precedes HSC phenotypic conversion into myofibroblasts.

Actins↗
PubMed2001

[HIV and the liver].

Explore the source record for details and available documents.

Alanine Transaminase↗
PubMed2000

Adenosarcoma arising in hepatic endometriosis.

We report a case of adenosarcoma arising in hepatic endometriosis. Both CT and MR scans demonstrated a huge heterogeneous mass containing septated, thick-walled cystic lesions. After enlarged right hepatectomy, the patient was asymptomatic with no abnormalities at liver and abdominal CT scan at 2-year follow-up.

Adenosarcoma↗
PubMed2000

PDGF-mediated chemoattraction of hepatic stellate cells by bile duct segments in cholestatic liver injury.

The accumulation of myofibroblasts and fibrosis around proliferating bile ducts in cholestatic liver disease has been attributed to the proliferation and phenotypic modulation of portal fibroblasts, whereas the contribution of hepatic stellate cells remains uncertain. There is increasing evidence to indicate that bile ducts may stimulate chemoattraction of hepatic stellate cells (HSC). In the present study, we undertook dynamic tests to examine such a possibility and to investigate the role of two potential mediators: platelet-derived growth factor-BB (PDGF-BB) and endothelin-1. Cholestasis was induced by bile duct ligation in rats. HSC were isolated from normal rats and culture activated into myofibroblasts expressing PDGF-beta receptors. Migration of myofibroblastic HSC was investigated in a Transwell chemotaxis filter assay. As compared with basal conditions, PDGF-BB (100 microg/l) and endothelin-1 (10(-8) M) induced a 3-fold and 1.7-fold increase in HSC migration, respectively. Bile duct segments isolated from cholestatic rats triggered a 3-fold increase in migration. This stimulation was significantly more potent than that observed in the presence of normal bile ducts. It was inhibited by neutralizing anti-PDGF antibodies and by STI571 PDGF receptor tyrosine kinase inhibitor, by 60% and 85%, respectively, whereas Bosentan, an endothelin receptor antagonist, had no significant inhibiting effect. In bile duct segments from cholestatic rats PDGF-B chain mRNA was detected at higher levels than in controls, whereas PDGF-BB was immunolocalized in bile duct epithelial cells. The results indicate that chemotaxis of HSC towards bile duct structures may contribute to the development of periductular fibrosis in cholestatic disorders, and that PDGF-BB is the major mediator in this process. In addition, anti-liver fibrogenic properties of STI571 are suggested by potent inhibition of myofibroblastic HSC function.

Animals↗
PubMed2000

Differential HFE allele expression in hemochromatosis heterozygotes.

BACKGROUND & AIMS: Hereditary hemochromatosis is associated with C282Y homozygosity. Some heterozygotes may also present with abnormal iron parameters. However, the precise role of H63D and C282Y mutations in iron overload is poorly understood. We investigated the level of expression of the mutated and unmutated HFE alleles in these heterozygous patients. METHODS: We studied the expression of HFE messenger RNAs in peripheral blood mononuclear cells from 34 heterozygotes using reverse-transcription polymerase chain reaction (PCR) followed by enzymatic digestion or sequence analysis of the PCR products, which allows relative quantification of mutated and unmutated transcripts. HFE proteins were quantified by Western blotting in Epstein-Barr virus-immortalized lymphocyte extracts from 2 C282Y and H63D homozygotes and a compound heterozygote. RESULTS: (187C > G; H63D) mutated transcripts predominated in H63D and compound heterozygotes and the normal transcripts in C282Y heterozygotes. The amount of HFE protein was increased in the H63D homozygotes and the compound heterozygote compared with the C282Y homozygotes. In addition, we found a new mutation at codon 282 (C282S) associated with severe iron overload. CONCLUSIONS: We demonstrate the existence of differential allelic expression of the HFE alleles, suggesting that the (187C > G; H63D) mutation plays a role in the disease expression in H63D heterozygotes, in particular when associated with environmental or host factors.

Adult↗
PubMed2000

Hepatocellular carcinoma and focal hepatic glycogenosis after prolonged azathioprine therapy.

A 22-year-old woman without predisposing liver disease developed focal hepatic glycogenosis and hepatocellular carcinoma after 6 years of azathioprine therapy for Crohn's disease. Hepatocellular carcinoma without cirrhosis has previously been described during immunosuppression, but this is the first report of disseminated focal hepatic glycogenosis after long-term azathioprine therapy.

Adult↗
PubMed1999

Phase I and phase II drug-metabolizing enzymes are expressed and heterogeneously distributed in the biliary epithelium.

Tissue expression of drug-metabolizing enzymes influences susceptibility to drugs and carcinogens. Because the biliary epithelium, exposed to bile-borne chemicals, may give rise to drug-induced cholangiopathies and to cholangiocarcinomas, we determined the pattern of expression of drug-metabolizing enzymes in this epithelium. We first demonstrated by blot analyses that biliary epithelial cells (BEC) isolated from human gallbladders display cytochrome P450 (CYP) 1A, 2E1, and 3A, microsomal epoxide hydrolase (mEH), alpha, mu, and pi glutathione S-transferase (GST), transcripts and proteins. We also identified CYP-associated steroid 6beta-hydroxylase activity in BEC. CYP and mEH expression was 5- to 20-fold lower in BEC than in autologous hepatocytes, and further differed by a higher ratio of CYP3A5/CYP3A4, and by CYP1A1 predominance over CYP1A2. alphaGST was highly expressed in both hepatocytes and BEC, while piGST was restricted to BEC. In approximately 50% of individuals, muGST was expressed in hepatocytes and at lower levels in BEC. By using the same antibodies as those used in immunoblots, we could show by immunohistochemistry that CYP2E1, CYP3A, mEH, alpha, mu, and piGST immunoreactivities are expressed and display a heterogeneous distribution in the epithelium lining the entire biliary tract except for small intrahepatic bile ducts that were devoid of CYP3A and alphaGST immunoreactivities. In conclusion, BEC contribute to phase II, and although to a lesser extent than hepatocytes, to phase I biotransformation. The distribution of drug-metabolizing enzymes in BEC suggest that they are heterogeneous in their ability to generate and detoxicate reactive metabolites, which may contribute to specific distributions of cholangiopathies.

Aryl Hydrocarbon Hydroxylases↗