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The acute toxicity of six metals [Hg, Cd, Cu, Zn, Cr(II), and Cr(VI)] to Daphnia magna neonates was evaluated using three different test media (Elendt M7, a complex medium containing EDTA; ASTM hard water and EEC, two simple media free of chelators). The EC50 values, at both 24 and 48 h, obtained for Zn, Cr(II), and Cr(VI) were similar in all of the media tested. Hg was more toxic in ASTM than in M7 and in EEC media. The toxicity of Cd and Cu was similar in ASTM and EEC media and higher when evaluated in M7 medium. Thus, M7 should be used only carefully for the toxicity evaluation of mixtures and effluents containing metals. It is recommended, however, that it be excluded from use in tests evaluating samples of unknown composition, or those known to contain Cu and Cd. For the metals tested in this study, a factor of five applied to each 48-h EC50 would be sufficient in order to attain the respective acute NOECs for immobility.  相似文献   

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The immunoglobulin (Ig) isotype (IgG, IgA, IgM) production of peripheral blood mononuclear cells from 28 patients having multiple myeloma (MM) was analyzed. The total Ig secreting capacity of the cells, as measured by ELISA from the cell culture medium, was not found to be significantly reduced in MM (1,118 +/- 1,394 micrograms/l) as compared to the values of 9 controls (898 +/- 520 micrograms/l), but a significant isotype switching towards the tumor paraprotein type was observed in the patients with active MM (p < 0.001). The percentage of IgG in the active IgG-MM was 88 +/- 11% and that of IgA in the active IgA-MM 83 +/- 13%, the control values being 44 +/- 11% for IgG and 44 +/- 13% for IgA. The proportions of isotypes resembled those of the controls in the inactive phase of the disease. Despite this dominating paraprotein class isotype production, no evidence of Ig gene clonal rearrangements was found in cells studied by either Southern blotting or the more sensitive polymerase chain reaction method, which suggests that polyclonal rather than monoclonal PB B cells are responsible for the Ig production observed.  相似文献   

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BACKGROUND: Hepatic artery thrombosis (HAT) after orthotopic liver transplantation remains a significant cause of graft loss in pediatric patients. We previously reported that the microsurgical techniques for arterial anastomosis can reduce the incidence of HAT in living related liver transplantation (LRLT). The purpose of this study is to analyze the risk factors for HAT after LRLT. A total of 245 patients received 250 liver transplants. METHODS: Eight arteries in eight patients, reconstructed with the use of loupe magnification (HAT; 1/8, 12.5%), were excluded from this study. We observed HAT in 4 patients of the 242 transplants (1.7%, HAT group). Seventeen factors were compared between the HAT and the control group (those without HAT). RESULTS: HAT occurred in 3 of 33 grafts (9%) from ABO-incompatible donors, whereas it occurred in 1 of 209 grafts (0.5%) from identical or compatible donors (P=0.008). The corrected volume of fresh-frozen plasma intraoperatively transfused in the HAT group (46.9+/-30.3 ml/kg) was significantly (P=0.015) different from that in the control group (10.2+/-1.9 ml/mg). In all four patients with HAT, emergent revisions of the anastomosis were performed. Two patients with ABO-incompatible grafts died of hepatic failure and sepsis. CONCLUSIONS: Although microsurgical techniques can minimize the surgical risk factors for HAT, overtransfusion of fresh-frozen plasma in high-risk patients (ABO incompatible) may be a critical factor in the development of HAT in LRLT.  相似文献   

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The most effective treatment for alcoholic liver disease is abstinence from alcohol and it is the only treatment for patients with alcoholic fatty liver. Although many empirical therapeutic agents have been studied in the short-term and long-term treatment of alcoholic hepatitis, results have been mainly inconclusive. To date, only corticosteroids have proved to decrease the short-term mortality rate of patients with severe forms of acute alcoholic hepatitis. Corticosteroids are not beneficial to the majority of patients with mild or moderate forms of acute alcoholic hepatitis; such patients improve with abstinence from alcohol and general supportive measures and do not need a specific short-term treatment. Most long-term trials have only showed that most patients with alcoholic liver disease were neither abstinent nor compliant, and that long-term survival was strongly correlated to abstinence from alcohol. In one study, propylthiouracil decreased the long-term mortality rate of compliant patients with severe alcoholic liver disease who reduced their alcohol intake; however, further clinical trials are needed before propylthiouracil can be recommended. In another study, colchicine decreased the long-term mortality rate of cirrhotic patients, 45% of whom had alcoholic cirrhosis. Results were highly significant, and the need for further clinical trials of colchicine in the long-term treatment of alcoholic and non-alcoholic cirrhosis is imperative. Enteral nutrition should also be studied in severely malnourished cirrhotic patients, since it was shown to decrease the short-term mortality rate of such patients in a recent study.  相似文献   

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Until the 1960s, liver disease of the alcoholic patient was attributed exclusively to dietary deficiencies. Since then, however, our understanding of the impact of alcoholism on nutritional status has undergone a progressive evolution. Alcohol, because of its high energy content, was at first perceived to act exclusively as 'empty calories' displacing other nutrients in the diet, and causing primary malnutrition through decreased intake of essential nutrients. With improvement in the overall nutrition of the population, the role of primary malnutrition waned and secondary malnutrition was emphasized as a result of a better understanding of maldigestion and malabsorption caused by chronic alcohol consumption and various diseases associated with chronic alcoholism. At the same time, the concept of the direct toxicity of alcohol came to the forefront as an explanation for the widespread cellular injury. Some of the hepatotoxicity was found to result from the metabolic disturbances associated with the oxidation of ethanol via the liver alcohol dehydrogenase (ADH) pathway and the redox changes produced by the generated NADH, which in turn affects the metabolism of lipids, carbohydrates, proteins and purines. Exaggeration of the redox change by the relative hypoxia which prevails physiologically in the perivenular zone contributes to the exacerbation of the ethanol-induced lesions in zone 3. In addition to ADH, ethanol can be oxidized by liver microsomes: studies over the last twenty years have culminated in the molecular elucidation of the ethanol-inducible cytochrome P450IIE1 (CYP2E1) which contributes not only to ethanol metabolism and tolerance, but also to the selective hepatic perivenular toxicity of various xenobiotics. Their activation by CYP2E1 now provides an understanding for the increased susceptibility of the heavy drinker to the toxicity of industrial solvents, anaesthetic agents, commonly prescribed drugs, 'over the counter' analgesics, chemical carcinogens and even nutritional factors such as vitamin A. Ethanol causes not only vitamin A depletion but it also enhances its hepatotoxicity. Furthermore, induction of the microsomal pathway contributes to increased acetaldehyde generation, with formation of protein adducts, resulting in antibody production, enzyme inactivation and decreased DNA repair; it is also associated with a striking impairment of the capacity of the liver to utilize oxygen. Moreover, acetaldehyde promotes glutathione depletion, free-radical mediated toxicity and lipid peroxidation. In addition, acetaldehyde affects hepatic collagen synthesis: both in vivo and in vitro (in cultured myofibroblasts and lipocytes), ethanol and its metabolite acetaldehyde were found to increase collagen accumulation and mRNA levels for collagen. This new understanding of the pathogenesis of alcoholic liver disease may eventually improve therapy with drugs and nutrients.  相似文献   

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Hepatic lymphangiomatosis is a rare disorder characterized by cystic dilatation of the lymphatic vessels in the hepatic parenchyma. It can occur in the liver alone, in the liver and spleen, or in multiple organs. Clinically, diagnosis can be difficult because of the rarity and protean manifestations of this disorder. We describe a 53-year-old woman with hepatic lymphangiomatosis in whom polycystic liver disease had been previously diagnosed. In addition, we review 12 cases of hepatic, splenic, and hepatosplenic lymphangiomatosis with or without systemic lymphangiomatosis and discuss the differential diagnosis.  相似文献   

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The present study examined the effects of progesterone (P4) treatments on estrous cyclicity and the loss of ovarian follicles during aging. Young rats received repeated treatments with P4 or empty implants between 3.5 and 8 mo of age. At 8 mo, ovaries were obtained from some animals to determine the numbers of resting follicles, and estrous cycle patterns and hormone levels were determined from other groups of treated females. In contrast to the cyclic increases in P4, estradiol (E2), LH, and FSH in control animals, P4-implanted rats exhibited elevated serum P4 but low E2, LH, and FSH levels. After implant treatments, the follicular reserve was significantly (p < 0.05) larger in P4-treated females (2012 +/- 297 resting follicles per ovary, n = 5 rats per group) than in regularly cyclic control rats (713 +/- 226 follicles per ovary, n = 7). The effects of P4 implants on the follicular reserve were associated with a subsequently higher incidence of regular estrous cycles after P4 treatment. These results demonstrate that P4 prevents cyclic increases in E2 secretion and is associated with a conservation of the ovarian follicular reserve and the maintenance of regular estrous cycle patterns, indicating a protective effect of P4 on the age-related loss of ovarian follicles.  相似文献   

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The following article reviews available data of the interaction of alcohol related liver disease and hepatitis C viral infection as well as special considerations for the treatment of these patients. Alcohol worsens the degree and accelerates the progression of hepatic injury, enhances the risk of developing hepatocellular carcinoma and decreases response to interferon therapy. Patients with hepatitis C should avoid alcohol ingestion.  相似文献   

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OBJECTIVE: To document the profile and role of malnutrition in alcoholic hepatitis, compared with chronic alcoholics and nonalcoholic chronic liver disease. METHODS: To this end, we studied 67 patients with alcoholic liver disease (ALD) (group I), 52 chronic alcoholics without histological evidence of liver disease (group II), 44 nonalcoholic cirrhotics (group III), and 52 healthy controls (group IV). Alcoholic and nonalcoholic calories were calculated and percentage dietary and nutritional deficiencies computed. Anthropometric indices, nitrogen balance, and immune status of the patients were assessed. RESULTS: Alcohol constituted about 48% of daily caloric intake in patients with ALD. The percentage mean intake of carbohydrate, protein, and energy was decreased in all three study groups compared with controls. The deficiencies were more pronounced in patients with severe than with moderate ALD. These deficiencies were more severe in the group III patients. Whereas body fat stores were maintained in groups I and II, reduction in lean body mass and serum transferrin was significant in patients in groups I and III. In group II patients compared to group I patients, the body mass index (19.9 +/- 4.0 vs. 22.3 +/- 3.4) and triceps skinfold thickness (6.1 +/- 4.8 vs. 10.2 +/- 5.6 mm) were significantly lower. CONCLUSIONS: 1) protein energy malnutrition is common in both alcoholic and nonalcoholic cirrhotics, but is more pronounced in the latter; 2) the degree and profile of malnutrition in chronic alcoholics and in alcoholic cirrhotics are comparable; 3) based on our results, we hypothesize that malnutrition may not play a primary role in the pathogenesis of ALD.  相似文献   

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It has been reported that serum hyaluronate [hyaluronic acid (HA)] concentrations are increased in liver diseases, especially in alcoholic liver disease (ALD). However, the characteristics of serum HA concentration in patients with ALD have not been studied. In this study, first, we measured serum HA concentrations in patients with different stages of both ALD and non-ALD to clarify the characteristics of serum HA concentration in patients with ALD. Second, we measured serum HA concentrations in patients with ALD sequentially after abstinence. We also measured serum HA concentrations in patients with chronic type C hepatitis before and after treatment with interferon. Finally, we analyzed the relationship between serum HA concentrations and the contents of type IV collagen and laminin in the livers of both ALD and non-ALD patients. Serum HA concentrations in liver disease were higher than the cut-off value, and increased significantly (p < 0.001) in parallel with the progression of hepatic fibrosis in both ALD and non-ALD patients. Serum HA concentrations in patients actively drinking with ALD were significantly higher (p < 0.001) than those in non-ALD. After 4 weeks of abstinence, these concentrations fell to the levels of non-ALD. Although serum ALT levels were decreased in 80% of patients treated with interferon, serum HA concentrations were not changed or increased. A significant correlation between serum HA concentrations and hepatic type IV collagen and laminin content was present in ALD, but not in non-ALD. These results clearly suggest that the increase of serum HA concentrations in ALD may be associated with not only hepatic fibrosis, but also alcohol drinking.  相似文献   

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BACKGROUND & AIMS: Inflammatory stimuli and lipid peroxidation up-regulate cyclooxygenase (COX)-2. This study evaluated the relationship between inflammatory mediators, COX expression, and pathological changes in experimental alcoholic liver disease. METHODS: Rats (5 per group) were fed ethanol and a diet containing saturated fat, corn oil, or fish oil by intragastric infusion. Dextrose isocalorically replaced ethanol in controls. In the first set of experiments, whole livers were analyzed. In the second set of experiments, Kupffer cells, endothelial cells, and hepatocytes were isolated from rats in each group. Pathological analyses and measurements of lipid peroxidation, tumor necrosis factor (TNF)-alpha, COX-1 and COX-2 messenger RNA (mRNA), endotoxin, and liver and plasma thromboxane were performed. RESULTS: Increased expression of COX-2 mRNA was detected in the livers of rats showing necroinflammatory changes. The Kupffer cell was the cell primarily responsible for the increase in COX-2 mRNA level. Increased expression of COX-2 was associated with increased levels of endotoxin, TNF-alpha mRNA, lipid peroxidation, and synthesis of thromboxane. COX-1 mRNA was decreased in Kupffer cells in rats with the most severe liver injury. CONCLUSIONS: Up-regulation of COX-2 in alcoholic liver injury occurred in the presence of proinflammatory stimuli and resulted in increased synthesis of inflammatory and vasoactive eicosanoids. Down-regulation of COX-1 may result in decreased synthesis of cytoprotective eicosanoids and additionally exacerbate liver injury.  相似文献   

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BACKGROUND: Elevation of serum IgA is a characteristic feature of alcoholic liver disease. It has been proposed that this occurs partly as an antigenic response to gut-derived proteins or acetaldehyde-modified liver proteins, but the principal antigens responsible remain unknown. AIMS: The goal of this study was to determine if serum IgA antibodies were present against human gut luminal antigens or liver antigens in alcoholic liver disease. PATIENTS AND METHODS: Twenty-nine patients with alcoholic liver disease, 10 with primary biliary cirrhosis, 12 with "other" liver diseases, 8 alcoholics, and 20 healthy subjects were studied. Western blotting was used to examine the reactivity of sera from these groups against human small and large bowel aspirates and liver tissue from alcoholic liver disease patients. RESULTS: Serum IgA antibodies to a 140 kDa colonic luminal protein were found in 22 (76%) patients in the alcoholic liver disease group (p < 0.0001), and 7 (24%) patients had serum IgA antibodies to a 40 kDa colonic luminal protein (p = 0.04). These responses were confined to colonic aspirates and not observed in other disease groups, alcoholics or healthy subjects. There was no significant serum IgA response to human liver proteins in alcoholic liver disease. CONCLUSIONS: Serum IgA antibodies to a human 140 kDa colonic luminal protein are frequently found in alcoholic liver disease. This novel antigen may contribute to the increased levels of circulating IgA in alcoholic liver disease.  相似文献   

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Recently, hepatitis GB virus C (HGBV-C) has been recovered from patients with non-A-E hepatitis. However, it has been unclear whether HGBV-C may be related to the development of alcoholic liver disease (ALD) or not. In this study, we determined HGBV-C RNA in sera from alcoholic patients without markers for hepatitis C and B viruses to evaluate the role of HGBV-C in ALD. Serum samples were obtained from 68 patients with ALD and 40 nonalcoholic patients with chronic type C liver disease. HGBV-C RNA was detected in only 3 of 68 (4.4%) patients with ALD, in 2 of 27 patients with hepatic fibrosis, and in 1 of 5 patients with chronic hepatitis. There was no HGBV-C RNA in sera from patients with fatty liver, alcoholic hepatitis, or cirrhosis. Serum levels of AST, ALT, and gamma-glutamyltranspeptidase in alcoholic patients with, as well as without, HGBV-C RNA decreased to normal levels after abstinence. In addition, an inflammatory change was not observed in liver biopsy specimens obtained from two HGBV-C-positive patients with alcoholic hepatic fibrosis. Our results clearly suggest that the prevalence of HGBV-C infection in patients with ALD is rare and that HGBV-C may not play an important role in the development of liver disease in alcoholics.  相似文献   

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One hundred and sixty-five coded liver biopsy specimens were studied by light microscopy to evaluate the occurrence and diagnostic significance of giant mitochondria, which have been identified as periodic acid-Schiff-negative globular hyaline cytoplasmic inclusions of regular outline, clearly distinguishable from Mallory bodies. In 4 cases, electron microscopy confirmed that these globules were in fact enlarged mitochondria. The incidence of giant mitochondria was significantly higher in patients with high alcohol consumption (72%) than in those with low or no alcohol intake (10%). Their presence was related to the amount of daily ethanol consumption and to the shortness of abstinence before the biopsy. It was independent of other changes in the liver, and was detected with similar frequency in biopsies showing different alcoholic liver diseases. Our study emphasizes that giant mitochondria may be detected by light microscopy in a high proportion of alcoholics, and rarely in nonalcoholic liver diseases. Although less specific, they are much more frequent than Mallory bodies. Consequently they should be considered as a diagnostic hint of recent and heavy alcoholsm.  相似文献   

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Report on 8 cases of congenital atresia or severe stenosis of the choanae. In 2 cases early transnasal surgery followed by canulation was necessary. One child died of pleuropneumonia and sepsis following asphyxia on the 10th day, when mouth-breathing had already been established.  相似文献   

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