PubMed Health⌕ Search

Biomedical subjects

C Degott

Publications and source records attributed to C Degott.

At least 91 records · Page 5Linked to original sources
PubMed1997

Persistence of hepatitis B virus DNA in serum and liver from patients with chronic hepatitis B after loss of HBsAg.

BACKGROUND/AIMS: The persistence of serum and liver hepatitis B virus (HBV) sequences in patients with chronic hepatitis B after loss of HBsAg has already been described. We have attempted to elucidate the significance of these HBV sequences after loss of HBsAg. METHODS: Fifteen patients were studied. We looked for serum and liver HBV DNA, using polymerase chain reaction (PCR) with different sets of primers and in situ hybridization. The sedimentation velocity of serum HBV DNA was measured on a gradient of sucrose in two patients. RESULTS: Serum HBV DNA was detected by PCR in four of the 14 patients tested at 0 months after loss of HBsAg, two patients remained HBV DNA positive until 12 months, and none was positive at 24 months. The sedimentation velocity of serum HBV DNA in sucrose was relatively similar to that of a chronic HBV carrier with active viral replication. Liver HBV DNA was demonstrated by PCR in all 15 patients and by in situ hybridization in six patients. CONCLUSIONS: Our results show that: 1) HBV DNA may persist in the serum in a minority of patients and may be associated with circulating viral particles; 2) HBV DNA persists in the liver in all patients and its extrachromosomal localization was shown by in situ hybridization technique in some cases. These results suggest the persistence of low-level HBV replication after loss of HBsAg.

Adult↗
PubMed1997

Interphase cytogenetic analysis reveals numerical chromosome aberrations in large liver cell dysplasia.

BACKGROUND/AIMS: Little is known about genetic alterations in large or small liver cell dysplasia. The aim of this study was to determine whether these lesions present numerical chromosome aberrations. METHODS: Eight patients with hepatocellular carcinoma on cirrhosis, five with large liver cell dysplasia and three with small liver cell dysplasia, were analysed by in situ hybridization with different centromeric nucleic acid probes specific respectively for chromosomes 1, 7, 17 and 18. In each case results were compared between dysplastic, tumoral and non-dysplastic cirrhotic cells. Four normal livers were also studied with the same method and served as cytogenetic controls. RESULTS: All cases of large liver cell dysplasia dysplayed a polysomic population for each investigated chromosome. A high variability of numerical chromosome aberrations was observed with a copy number of chromosomes which ranged from two to more than six. By contrast, only one case of small liver cell dysplasia showed chromosomal anomalies. Numerical aberrations of at least one chromosome were observed in six of the eight hepatocellular carcinoma while the non-dysplastic cirrhosis and normal liver always showed a diploid pattern. CONCLUSIONS: These results demonstrate that cellular modifications in large liver cell dysplasia coexist with an early acquisition of genomic alterations, supporting the view that these phenotypic changes are preneoplastic.

Adult↗
PubMed1997

Subfulminant syncytial giant cell hepatitis: recurrence after liver transplantation treated with ribavirin.

We report the case of an adult patient affected by acute syncytial giant cell hepatitis which had a subfulminant course leading to liver transplantation. Syncytial giant cell hepatitis recurred after transplantation and was efficiently treated with ribavirin. In this patient, the recurrence of the disease, the presence of filamentous strands on electron microscopy during both bouts of hepatitis and the efficacy of ribavirin on post-transplantation hepatitis suggest that the disease was caused by an original virus. This observation also suggests that early administration of ribavirin in patients affected by acute syncytia; giant cell hepatitis of unknown origin could avoid liver transplantation.

Acute Disease↗
PubMed1997

Complement activation after ischemia-reperfusion in human liver allografts: incidence and pathophysiological relevance.

BACKGROUND & AIMS: Little is known about the occurrence and possible consequences of local complement activation in human liver transplantation. The aim of this study was to search for signs of complement activation in human liver allografts and evaluate their relationship to cell injury and leukocyte sequestration. METHODS: In 33 postreperfusion biopsy specimens, 9 preoperative specimens, and 10 intraoperative specimens, the cytolytic membrane attack complex of complement was localized, expression of complement inhibitors was evaluated, and intragraft accumulation of leukocytes and platelets was quantitated. RESULTS: In control samples and preoperative biopsy specimens, the membrane attack complex was detected only in extracellular deposits, associated with its soluble inhibitors clusterin and vitronectin. Comparable observations were performed in 14 postoperative specimens. In the remaining 19 postoperative specimens, membrane attack complex decorated a variable proportion of hepatocytes. The extent of membrane attack complex deposition correlated with the increase in postoperative aspartate aminotransferase levels in serum (P = 0.002) and the decrease in postoperative factor V levels in serum (P = 0.002). It also correlated with the number of leukocytes and platelets accumulating within the graft (P < or = 0.001). CONCLUSIONS: Local complement activation is frequent during human liver transplantation and probably contributes to cell injury and leukocyte sequestration in the allograft.

Adult↗
PubMed1997

Premature oxidative aging of hepatic mitochondrial DNA in Wilson's disease.

BACKGROUND & AIMS: Aging is associated with and may be caused by acquired somatic mutations of the mitochondrial genome. In Wilson's disease, inherited mutations of a nuclear gene encoding a copper transporter cause accumulation of copper in the liver, particularly within mitochondria. Because copper has prooxidant properties and the mitochondrial genome is particularly susceptible to oxidative damage, we hypothesized that Wilson's disease may cause premature oxidative aging of mitochondrial DNA. METHODS: Hepatic DNA was screened for large mitochondrial DNA deletion(s) in 16 patients with Wilson's disease and 67 control subjects. Deleted mitochondrial DNA copies were amplified by polymerase chain reaction and were sequenced. RESULTS: Although 15 of the 16 patients with Wilson's disease were 30 years old or younger, 8 of them (50%), including the 6 patients with cirrhosis (100%), had diverse mitochondrial DNA deletions, whereas only 2 controls (3%), aged 39 and 45 years, showed a mitochondrial DNA deletion. CONCLUSIONS: Wilson's disease is associated with frequent, diverse, and early deletions of mitochondrial DNA. Accumulation of prooxidant copper within hepatic mitochondria may cause this premature oxidative aging of mitochondrial DNA. Thus, inherited mutations of a nuclear gene may cause somatic mutations of the mitochondrial genome in this condition.

Adolescent↗
PubMed1997

Prolonged interferon-alpha therapy of hepatitis B virus-related decompensated cirrhosis.

Interferon alpha therapy of hepatitis B virus-related decompensated cirrhosis with the dose and the duration generally used is frequently associated with severe side-effects and reactivations. Between 1989 and 1996, 15 patients with hepatitis B virus-related decompensated cirrhosis received prolonged (3-48 months) low-dose (3 million units) IFN-alpha therapy. Ten patients (66%) had a sustained loss of serum hepatitis B virus DNA and hepatitis Be antigen (if present initially) associated with a decrease of aminotransferase levels into the normal range. During follow-up of these 10 patients, seven had a marked clinical improvement and are alive and fully active. One has an hepatocellular carcinoma, and two died without reactivation. Among the five other patients, two had a transient loss of serum HBV DNA followed by reactivation and three did not respond to therapy. During follow-up, one of these five patients died and one underwent liver transplantation. Severe complications, possibly related to interferon were uncommon and included bacterial infection in one case and variceal bleeding in two cases. Eleven of the 15 patients treated are alive after 1.5-7 years of follow-up. Hence, in patients with hepatitis B-related cirrhosis, prolonged low-dose IFN-alpha therapy is relatively well tolerated and may induce a sustained inhibition of hepatitis B virus replication with marked clinical improvement.

Adult↗
PubMed1996

Organ-specific disease provoked by systemic autoimmunity.

Rheumatoid arthritis (RA) is a chronic joint disease characterized by leukocyte invasion and synoviocyte activation followed by cartilage and bone destruction. Its etiology and pathogenesis are poorly understood. We describe a spontaneous mouse model of this syndrome, generated fortuitously by crossing a T cell receptor (TCR) transgenic line with the NOD strain. All offspring develop a joint disease highly reminiscent of RA in man. The trigger for the murine disorder is chance recognition of a NOD-derived major histocompatibility complex (MHC) class II molecule by the transgenic TCR; progression to arthritis involves CD4+ T, B, and probably myeloid cells. Thus, a joint-specific disease need not arise from response to a joint-specific antigen but can be precipitated by a breakdown in general mechanisms of self-tolerance resulting in systemic self-reactivity. We suggest that human RA develops by an analogous mechanism.

Alleles↗
PubMed1996

Auxiliary liver transplantation: regeneration of the native liver and outcome in 30 patients with fulminant hepatic failure--a multicenter European study.

Auxiliary liver transplantation (LT) is a special procedure of LT which could be proposed to patients with fulminant hepatic failure (FHF) and has for aim that complete regeneration of the native liver (NL) left in place will allow the graft recipient to resume normal liver function after allograft withdrawal. We report 30 cases of auxiliary LT performed for FHF in 12 European centers. Twenty-five of 30 patients were younger than 50 years. The cause of FHF was hepatitis A virus (HAV) in 4 patients, hepatitis B virus (HBV) in 7, paracetamol overdose in 5, ecstasy in 2, hepatotoxic drugs in 4, autoimmune hepatitis in 2, liver lesions of preeclampsia in 1 and unknown in 5. A postoperative, both clinical and histological follow-up of more than 3 weeks was obtained in 22 patients, enabling us to look for indicators predictive of NL regeneration and outcome. Histological changes observed in the NL included complete regeneration in 68%, incomplete regeneration with obvious fibrous sequelae in 14% and severe liver fibrosis or cirrhosis in 18%, of the 22 patients studied. The percentage and distribution of necrosis observed in tissue samples of the NL at the time of transplantation was not related to the final outcome. Complete NL regeneration was observed in 15 patients, out of whom 14 were younger than 40 years. Patients with complete regeneration were mainly affected by FHF due to HAV, HBV, or paracetamol overdose. After a follow-up of 18/11 (mean/median) months (range, 3 to 67 months), 19 of the 30 patients (63%) survived and 13 of them (68%), i.e., 43% of the 30 patients, had resumed normal NL function, with interrupted immunosuppression, the ultimate goal of emergency auxiliary LT. We conclude that, in patients with FHF, auxiliary LT is a procedure feasible in a number of centers and is associated with a complete regeneration capability of the NL in a majority of survivors, especially in those younger than 40 years. Confirmation of these encouraging preliminary results by large-scale prospective studies is required.

Adolescent↗
PubMed1996

Acute and chronic hepatic steatosis lead to in vivo lipid peroxidation in mice.

BACKGROUND/AIMS: Several liver diseases that are characterized by chronic steatosis lead to steatohepatitis lesions in some susceptible subjects. We tested the hypothesis that acute or chronic steatosis may lead to lipid peroxidation. METHODS: Diverse steatogenic treatments were administered to mice, and lipid peroxidation was assessed by measuring thiobarbituric acid reactants in the liver and the exhalation of ethane in breath. RESULTS: Administration of ethanol (5 g/kg), tetracycline, chlortetracycline, demeclocycline (0.25 mmol/kg each), amineptine (1 mmol/kg), amiodarone (1 mmol/kg), pirprofen (2 mmol/kg), or valproate (2 mmol/kg) led to microvesicular steatosis of the liver and lipid peroxidation. After tetracycline administration, hepatic triglycerides reached a maximum at 24 h and then declined; ethane exhalation followed a similar time course. Microvesicular steatosis and lipid peroxidation were also observed after 4 days of treatment with either ethionine (0.02 mmol/kg daily) or dexamethasone (0.25 mmol/kg daily) or after 7 days of tetracycline (0.25 mmol/kg daily) administration. Administration of ethanol in the drinking water for 5.5 months led to macrovacuolar and microvesicular steatosis, lipid peroxidation, and a few necrotic hepatocytes. CONCLUSIONS: We conclude that acute or chronic fat deposition due to a variety of compounds was associated with lipid peroxidation in mice. We suggest that the presence of oxidizable fat in the liver leads to peroxidation, and that chronic lipid peroxidation might represent the common (but not exclusive) mechanism for the possible development of steatohepatitis lesions in conditions characterized by chronic steatosis.

Acute Disease↗
PubMed1996

Survival and prognostic factors in patients with severe alcoholic hepatitis treated with prednisolone.

BACKGROUND & AIMS: Corticosteroids have been shown to significantly decrease short-term mortality in patients with severe alcoholic hepatitis. However, independent factors associated with a favorable outcome and long-term survival are unknown. The aim of this study was to examine prognostic factors and long-term survival in patients with biopsy-proven severe alcoholic hepatitis. METHODS: Of 183 patients studied, 61 had been randomized in a previous trial; 32 of them were treated with prednisolone (group I) and 29 were not treated (group II); 61 were treated from the end of this randomized trial (group III); and 61 were simulated (group IV). RESULTS: At 1 year, survival in group I (69%; confidence interval [CI], 57%-81%) and group III (71%; CI, 55%-87%) was better than in the nontreated groups (group II, 41%; CI, 23%-59%; P = 0.01) (group IV, 50%; CI, 37%-63%; P = 0.05). At 2 years, survival was not significantly different. Treated patients with marked liver polymorphonuclear infiltrate had better 1-year survival (76%; CI, 64%-88%) than the others (53%; CI, 35%-71%; P = 0.05). Treated patients with polymorphonuclear counts of > 5500/mm3 had better 1-year survival (77%; CI, 65%-89%) than the others (40%; CI, 14%-66%; P = 0.003). In the 93 treated patients, liver polymorphonuclear infiltrate (P < 0.03) and polymorphonuclear count (P < 0.001) were independently correlated with 1-year survival. CONCLUSIONS: Prednisolone reduced mortality by at least 1 year. Liver polymorphonuclear infiltrate and polymorphonuclear count were independent prognostic factors.

Female↗
PubMed1996

Relationship between composition of lymphoid cell infiltrates in the liver and replication status in chronic hepatitis B: an immunohistochemical study.

The purpose of this in situ immunophenotyping study was to assess the nature of lymphoid cells involved in chronic hepatitis B with various levels of replication. Replicative status was studied in 25 patients with chronic hepatitis B. Different subsets of T cells, B cells, natural killer cells, and follicular dendritic cells were counted with a computerized image analyzer. Twelve patients had chronic hepatitis B with a high level of replication, nine without replication, and four with a low level of replication. The number of CD3+ T cells was significantly higher in the liver of patients with replication. In all cases, CD8+ T cells were the most numerous cells in the lobules and CD4+ T cells were the most numerous cells in the portal tract. Intra-portal lymphoid follicles were observed in 33% of patients with a high level of replication. The CD57+ natural killer cells were more numerous in patients with a low level of replication. This study suggests that in immunocompetent patients, the intensity and type of hepatic immune response are directly determined by the HBV replication.

Adult↗
PubMed1996

Plasma cell variant of Castleman's disease localized to the liver: a case report.

Localized plasma cell variant of Castleman's disease is an uncommon lymphoproliferative disorder. It is characterized by numerous, evenly distributed germinal centres with moderate or extensive sheets of plasma cells in between. It may be associated with a wide variety of systemic manifestations that disappear after removal of lesion. Rare cases of Castleman's disease have been reported in extranodal locations, i.e. muscle, larynx, vulva, lung, pericardium and cranium. We report the first the case of a liver tumour with clinico-pathological features of the plasma cell variant of Castleman's disease. This tumour differs from the hepatic inflammatory pseudotumour, which is frequently associated with infectious conditions.

Adult↗
PubMed1996

A new hepadnavirus endemic in arctic ground squirrels in Alaska.

We present evidence for a novel member of the hepadnavirus family that is endemic in wild arctic ground squirrels (Spermophylus parryi kennicotti) in Alaska. This virus, designated arctic squirrel hepatitis virus (ASHV), was initially detected in the livers of animals bearing large hepatic nodules by nucleic acid hybridization with hepadnavirus probes and in plasma by cross-reactivity with antibodies to hepadnavirus surface and core antigens. The complete nucleotide sequence of the 3,302-bp-long ASHV genome was determined and compared with those of ground squirrel hepatitis virus (GSHV) and woodchuck hepatitis virus (WHV); all sequences were organized into four open reading frames, designated pre-C/C, pre-S/S, pol, and X. Despite roughly equivalent variability among the three rodent hepadnaviruses (around 16% base and 19% amino acid exchanges), ASHV appeared to be more closely related to GSHV than to WHV in phylogenetic analysis. Accordingly, preliminary studies of the pathology of ASHV infection suggested that ASHV may be a less efficient oncogenic agent than WHV. About one-third of aged animals maintained in captivity, including virus-infected as well as uninfected squirrels, developed large liver nodules, consisting of hepatocellular adenomas or carcinomas or nonmalignant lesions characterized by drastic microvesicular steatosis. ASHV-infected arctic ground squirrels may serve as a new model with which to analyze the contribution of hepadnavirus- and host-specific determinants to liver pathology and tumorigenesis.

Alaska↗
PubMed1995

PML nuclear bodies are general targets for inflammation and cell proliferation.

Acute promyelocytic leukemia is associated with a t(15;17) translocation that generates a fusion product between PML and the retinoic acid receptor alpha. Recently, PML was shown to concentrate within subnuclear domains, referred to as nuclear bodies, that are disorganized in acute promyelocytic leukemia cells. This observation provided the first evidence that alteration of a nuclear structure may play a role in human pathogenesis. In an attempt to clarify the role of PML and, more generally, of the associated nuclear bodies, we used immunohistochemistry to explore the expression of PML in normal, inflammatory, and neoplastic human tissues. With the exception of endothelial cells and macrophages that contain a high amount of PML protein, a weak speckled labeling pattern was observed in the nucleus of all cell types analyzed. By contrast to normal tissues, the level of PML expression was considerably enhanced in inflammatory tissues, predominantly around the mononuclear cell infiltrate, as well as during either normal or pathological proliferative states, in particular in tumoral pathology. Surprisingly, in most hepatocellular carcinoma, a cytoplasmic delocalization of PML was observed. Finally, the number of PML nuclear bodies increased up to twice their normal value as quiescent cultured cells were stimulated to grow upon serum addition. Altogether these results strongly suggest that the PML-associated nuclear bodies are implicated both in the inflammatory process and in cell growth control.

Adenocarcinoma↗