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1.
We report our experience of pediatric liver transplantation with partial grafts from non-heart beating donors (NHBD). Controlled donors less than 40 years of age with a warm ischemia time (WI) of less than 30 min were considered for pediatric recipients. Death was declared 5 min after asystole. A super-rapid recovery technique with aortic and portal perfusion was utilized. Mean donor age was 29 years and WI 14.6 min (range 11–18). Seven children, mean age 4.9 years (0.7–11), median weight 20 kg (8.4–53) received NHBD segmental liver grafts. Diagnoses included seronegative hepatitis, neonatal sclerosing cholangitis, familial intrahepatic cholestasis, hepatoblastoma, primary hyperoxaluria and factor VII deficiency (n = 2).The grafts included four reduced and one split left lateral segments, one left lobe and one right auxiliary graft. Mean cold ischemia was 7.3 h (6.2–8.8). Complications included one pleural effusion and one biliary collection drained percutaneously. At 20 months (10–36) follow-up all children are alive and well with functioning grafts.
Donation after cardiac death is a significant source of liver grafts for adults and children with careful donor selection and short cold ischemic times.  相似文献   
2.
Wilson's disease (WD) is a rare liver-based disorder of copper metabolism. Prognostic criteria described by our group in 1986 to predict death without transplantation have not been universally validated. The clinical features of 88 children were reviewed, retrospectively in 74 and prospectively in 14. Data from the retrospectively recruited patients that died or survived on long-term chelation were used to evaluate the validity of our old scoring system and to devise a new prognostic index, then assessed in the 14 prospectively recruited patients. Using the old scoring system, 5 children scoring > or = 7, the cutoff value for death without transplantation, survived, whereas 4 scoring < or = 7 died (sensitivity 87% and specificity 90%). A new index based on serum bilirubin, international normalized ratio, aspartate aminotransferase (AST), and white cell count (WCC) at presentation identified a cutoff score of 11 for death and proved to be 93% sensitive and 98% specific, with a positive predictive value of 88%. When the new index was evaluated prospectively in 14 patients, it predicted the need for transplantation in only the 4 who required it, although 1 child with a score of 11 survived on medical treatment. In conclusion, the new Wilson Index is more sensitive and specific in predicting mortality without transplantation than the old scoring system, but needs to be validated in a larger number of patients.  相似文献   
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The relative virulence of different isolates of Mycobacterium avium has been linked to their capacity to trigger the secretion of TNF from the macrophages they infect. Smooth opaque (SmOp) variants of Myco. avium have been shown to trigger higher expression of TNF-alpha by macrophages in vitro than the smooth transparent (SmTr) variants. To analyse the role of TNF in resistance to infection by Myco. avium, we studied the infection by two different morphotypes of strain 2.151 of Myco. avium both in vitro and in vivo in the presence or absence of neutralizing antibodies to TNF. No effects were found in vitro regarding the growth of either isolate of Myco. avium. In vivo, only the virulent SmTr morphotype showed enhanced growth in the presence of the neutralizing antibodies. This enhancement occurred relatively late when priming for TNF secretion in vivo was evident. Among four isolates of Myco. avium, three virulent ones induced a marked priming for TNF release and one avirulent strain did not. Mycobacterium tuberculosis H37Ra, which is very active in inducing TNF release due to its lipoarabinomannan moiety, was used to compare with the previous results. The growth of H37Ra in macrophages was increased in vitro by the neutralization of TNF and neutralization of either TNF and/or interferon-gamma (IFN-gamma) enhanced the in vivo proliferation of this microbe in the spleen and liver of infected animals, whereas only the combination of both anti-TNF and anti-IFN-gamma enhanced bacterial proliferation in the lung. We conclude that resistance to the avirulent strains of Myco. avium did not involve TNF, but rather antimicrobial mechanisms expressed constitutively in the mononuclear phagocytes. In contrast, TNF plays an important role in the control of Myco. tuberculosis H37Ra infection.  相似文献   
5.
Activated circulating T lymphocytes expressing HLA-DR (mean +/- s.d. 11.0 +/- 5.2%) or interleukin-2 receptor (IL-2R) (2.1 +/- 1.7%) were significantly increased in 63 children with chronic hepatitis B virus (HBV) infection when compared with 33 age-matched healthy controls (3.0 +/- 1.3%, P less than 0.01, and 0.1 +/- 0.4%, P less than 0.01). HBeAg-positive patients had higher percentage of DR (11.9 +/- 5.1%) or IL-2R (2.4 +/- 1.7%) positive T lymphocytes than anti-HBe-positive children (7.4 +/- 3.6% and 1.1 +/- 1.5%, P less than 0.01 and P = 0.02 respectively). Similarly, HBV DNA-positive patients had higher percentage of DR (10.5 +/- 3.3) or IL-2R (3.2 +/- 1.7%) positive T cells than HBV DNA-negative children (6.6 +/- 2.8% and 1.2 +/- 1.5%, P less than 0.01 for both). There was a positive correlation between percentage of DR positive T lymphocytes and levels of HBV DNA. Sixty-two per cent of the DR-positive T lymphocytes were cytotoxic/suppressor and 35% helper/inducer. The relationship between viral replication and T lymphocyte activation is discussed.  相似文献   
6.
To study the possible role of T cells bearing the gamma delta T cell receptor (TCR) heterodimer in the pathogenesis of autoimmune chronic active hepatitis (AI-CAH) and primary sclerosing cholangitis (PSC) in children, we measured levels of gamma delta+ T cells in the peripheral blood, assessed the proportion of cells bearing the disulphide-linked (BB3+) and non-disulphide-linked (A13+) subtypes of the receptor, and studied the co-expression of TCR-gamma delta and the activation markers HLA-DR and IL-2 receptor (IL-2R), and the memory cell marker CD45RO. Percentage levels and absolute numbers of gamma delta +T cells were higher in both groups of patients than in controls (P less than 0.01), mainly as a result of an increase in both percentage levels and absolute numbers of the A13+ subtype (P less than 0.001). Co-expression of IL-2R and TCR-gamma delta was not found in controls but was present in some patients with AI-CAH (four out of 17) and PSC (six out of 12) at low levels (median 2.3%, range 1.7-5.0%). Expression of HLA-DR on gamma delta+ T cells was similar in both groups of patients and controls. The majority of gamma delta+ T cells in children with AI-CAH and PSC also expressed CD45RO (74.7 +/- 18.4% and 79.8 +/- 24.3%, respectively) at levels significantly higher than in controls (53.3 +/- 17.2%, P less than 0.01). These results suggest that autoimmune liver diseases in children are associated with an expansion and activation of gamma delta+ T cells in the peripheral blood, which may be important in the pathogenesis of these disorders.  相似文献   
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Background: Anti-mitochondrial antibody is the diagnostic hallmark of primary biliary cirrhosis. Its role in the aetiology of primary biliary cirrhosis is controversial. Methods: Two cases of neonatal hepatitis seropositive for anti-mitochondrial antibody are described. Anti-mitochondrial antibody Ig isotype and epitopic specificity were investigated by immunofluorescence and enzyme immunoassays. Results: In both infants anti-mitochondrial antibody was of the G class, mainly G1 and G3 subclasses, and reacted with two synthetic peptides reproducing major M2 epitopic regions: inner lipoyl domain pyruvate dehydrogenase complex (PDC)-E2162-176 and PDC-E3 binding protein (PDC-E3BP)86-100. One infant also reacted with outer lipoyl domain PDC-E235-49, and 2-oxoglutarate dehydrogenase complex (OGDC)-E299-113. An identical pattern of reactivity was present in their mothers, indicating the maternal origin of the antibodies. Anti-mitochondrial antibody disappeared in the infants with the disappearance of the liver pathology. Conclusions: The simultaneous disappearance of hepatitis and anti-mitochondrial antibody in the infants suggests a possible causal link between the two.  相似文献   
9.
BACKGROUND/AIMS: Data regarding hepatitis B virus (HBV) genomic heterogeneity in perinatal infection are incomplete, although HBV variants might be involved in neonatal fulminant hepatitis (ALF). We investigated HBV variability in infected babies showing different clinical courses. METHODS: We analyzed HBV genomes isolated from nine vertically infected babies and the mothers of four of them. Two infants born to HBe-antigen (HBeAg)-positive women developed a chronic infection; seven babies (six born to anti-HBe mothers) developed acute hepatitis that had a fulminant course in four cases and a benign course in three. Two babies developing ALF received anti-HBV immunoprophylaxis at birth. RESULTS: Viruses carrying no significant mutation infected infants born to HBeAg-positive women. HBeAg-defective viruses were detected both in children with benign and fulminant hepatitis and their mothers. A double nucleotide mutation at positions 1762 and 1764 of the HBV core-promoter was found in two of the four infants with ALF, although it was not detected in isolates from the mother of one of them. No significant S gene mutation was found in HBV from any of the babies. CONCLUSIONS: This study indicates that HBV genomic heterogeneity is not primarily involved either in the evolution of the infection or the failure of neonatal HBV immunoprophylaxis.  相似文献   
10.
Hepatocytes isolated from patients with chronic liver disease are often covered by immunoglobulin. The aim of the present study was to establish whether this surface immunoglobulin (SIg) mediates liver cell damage. Freshly isolated hepatocytes from percutaneous liver biopsy of 16 patients with chronic active hepatitis (CAH) (6 HBsAg positive), 3 with HBsAg-positive chronic lobular hepatitis (CLH), 5 with HBsAg-positive chronic persistent hepatitis (CPH) and 12 with minor histological abnormalities (MHA) (5 HBsAg positive) were divided into two aliquots. One was studied for the presence of membrane-bound immunoglobulin and the third component of complement by direct immunofluorescence and the other was incubated, in an allogeneic cytotoxic assay, with peripheral blood mononuclear cells prepared from healthy volunteers as a source of effectors for antibody-dependent cell-mediated cytotoxicity (ADCC). Liver biopsies were scored for portal and parenchymal inflammatory activity. The percentage of SIg positive hepatocytes was significantly higher in patients with CAH (median 52.5%) than in patients with CLH/CPH (20.5%) or in patients with MHA (1%). Percentages of SIg-positive liver cells were significantly correlated with total liver biopsy scores and with both portal or parenchymal scores considered independently. SIg were found to belong to the IgG class in all groups of patients. When hepatocytes were cultured with normal human lymphocytes, allogeneic cytotoxicity values were significantly higher in patients with CAH (median 34%) than in patients with CLH and CPH (18%) or in those with MHA (12%). Percentage cytotoxicity was positively correlated with total biopsy scores and with portal activity but not with parenchymal activity, suggesting that ADCC might play a damaging role mainly in the portal areas.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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