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1.
Background and Aim: This study investigated the clinical features of hepatocellular carcinoma in patients with sustained virological response to interferon for hepatitis C viral (HCV) infection. Methods: A total of 7715 patients with HCV infection were treated with interferon and followed up for more than 1 year after withdrawal of interferon in 64 Japanese hospitals and clinics between July 1988 and August 2001. Sustained virological response was obtained in 2515 (32.6%) patients. Of these 2515 patients, clinical data were collected for 38 patients in whom hepatocellular carcinoma developed. Sustained virological response was defined as HCV RNA negativity more than 6 months after the termination of interferon. Results: All patients were HCV RNA negative at the time of diagnosis of hepatocellular carcinoma. The median period until the detection of hepatocellular carcinoma was 4.7 years (range 1.4–9.0 years). There were significant improvements in hepatic function including serum albumin, aspartate aminotransferase, alanine aminotransferase, indocyanine green test, platelet count and histological activity grade in comparison with those before interferon therapy and at the onset of hepatocellular carcinoma. The maximum tumor size in patients without medical follow‐up for 1 year or more (median: 60 mm) was significantly larger than in patients who were periodically followed up for 6 months or less (median: 25 mm) (P = 0.002). Conclusions: The present findings emphasize the importance of regular medical follow up of patients with HCV infection, as even patients showing a sustained virological response to interferon and in whom hepatic function has improved have the potential to develop hepatocellular carcinoma.  相似文献   
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Background and Aim:  We recently reported that cyclooxygenase (COX)-2 is upregulated in the rat small intestine after administration of indomethacin, and this may be the key to non-steroidal anti-inflammatory drug (NSAID)-induced intestinal damage. The present study investigated the mechanism for COX-2 expression induced in the rat small intestine by indomethacin, in relation with ulcerogenic processes.
Methods:  Animals were given indomethacin or SC-560 p.o., and the intestinal mucosa was examined 24 h later.
Results:  Indomethacin caused hemorrhagic lesions in the small intestine, accompanied with an increase in intestinal motility, bacterial invasion and inducible nitric oxide synthase (iNOS) activity, as well as the expression of COX-2 mRNA in the mucosa. Although SC-560 did not cause any damage, this agent caused intestinal hypermotility, the bacterial invasion and the upregulation of COX-2 expression. The mucosal PGE2 content was decreased by SC-560 at 3 h but recovered 12 h later, and this recovery of PGE2 was attenuated by both atropine and ampicillin, in addition to rofecoxib. The intestinal hypermotility response to indomethacin was prevented by both 16,16-dimethyl PGE2 and atropine, but not ampicillin. Yet all these agents inhibited not only the bacterial invasion but also the expression of COX-2 and iNOS activity in the intestinal mucosa following indomethacin treatment, resulting in the prevention of intestinal lesions.
Conclusion:  These results suggest that COX-2 expression in the intestinal mucosa following the administration of indomethacin is associated with intestinal hypermotility and bacterial invasion. The intestinal hypermotility caused by COX-1 inhibition may be a key to COX-2 expression after administration of NSAIDs and their intestinal ulcerogenic properties.  相似文献   
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Two infants with biliary atresia who exhibited three-fold increased trough levels of tacrolimus and required reduced doses during episodes of acute infantile diarrhea within 5 months of liver transplantation are described. The cause of the increase was not explained simply by hemoconcentration as a result of significant loss of extracellular fluid during these episodes. It does highlight an important issue: that of the continuing need to carefully monitor the trough levels of tacrolimus in such infants.  相似文献   
4.
Mixed cryoglobulinaemia is frequently associated with chronic hepatitis. We report a patient with mixed cryoglobulinaemia, hepatitis C virus (HCV) infection and palpable purpura. The skin manifestations were diagnosed as leucocytoclastic vasculitis in view of both the clinical appearance and the histological findings. In this study, we demonstrated the presence of IgG–class anti–HCV–antibody. HCV–RNA and IgA–class rheumatoid factor in the cryoprecipitate. These results suggest that the cryoglobulinaemia in this case was caused by aggregation of an immune complex comprised of HCV and anti–HCV antibody with IgA–type–rheumatoid factor, and that this led to a cutaneous vasculitis.  相似文献   
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Background The role of IgE in airway hyperreaetivity is obscure. Objective In order to clarify the role of IgE in airway hyperreactivity, we investigated the effect of anti-IL-4 monoclonal antibody, rapamycin and interferon-γ on the antigen-induced IgE response, airway eosinophilia and hyperreactivity in mice. Methods Mice were immunized with an antigen (ovalbumin; OA) at intervals of 12 days. OA was inhaled 10 days after the secondary immunization. Twenty-four hours after the last inhalation, airway reactivity to acetylcholine was measured and bronchoalveolar lavage fluid (BALF) was obtained. Results Three inhalations of antigen caused an increase in the number of eosinophils in bronchoalveolar lavage fluid (BALF) and in airway hyperreactivity to acetylcholine with a significant elevation of serum IgE level. Anti-IL-4 at a dose of 1000 μg/animal and rapamycin at doses between 0.1 and 1 mg/kg inhibited the IgE production, but did not affect the airway eosinophilia or hyperreactivity to acetylcholine. In contrast, IFN-γ clearly inhibited the antigen-induced airway eosinophilia and hyperreactivity, but did not affect the IgE antibody production. Conclusion These results suggest that the inhibition of IgE production does not suppress the onset of airway hyperreactivity and eosinophilia in mice, and that IFN-γ inhibits the antigen-induced airway hyperreactivity, probably due to the inhibition of airway eosinophilia.  相似文献   
8.
BACKGROUND: Decreased energy expenditure and increased food intake are principal causes for obesity. In the present study, genotypes of beta(3)-adrenergic receptor (beta(3)AR) and of melanocortin-4 receptor (MC4R), both of which are believed to have a close link to the cause of obesity, were analyzed and compared with phenotypes of childhood obesity. METHODS: Thirty-five obese children with moderate to severe obesity were enrolled. Direct sequencing of the MC4R coding region and pinpoint-polymerase chain reaction were used to detect genomic variation in the beta(3)AR gene using peripheral blood-derived DNA. RESULTS: Allele frequency of Trp64Arg variation in the beta(3)AR gene in the obese subjects was 0.16, which is comparable with that in the healthy general population in eastern Asia. Comparison of phenotypical characteristics did not show a significant difference between Trp/Trp and Trp/Arg subjects. It was notable that body height SD was significantly higher in the Trp/Trp than the Trp/Arg subjects (0.93 +/- 1.0 SD vs 0.07 +/- 1.3 SD, P= 0.03). Annual weight gains were far beyond a hypothetical fat gain in an Arg64 heterozygote with decreased energy consumption, suggesting increased food intake in childhood obesity. There was, however, no variation in the MC4R gene despite thorough sequencing of the entire coding region. CONCLUSIONS: The Trp64Arg variation in the beta(3)AR gene has no relationship to the degree or the incidence of childhood obesity. The majority of childhood obesity can be characterized as tall stature, more rapid weight gain than that expected by decreased energy expenditure. Further investigation is necessary in regard to the increased food intake as a major cause of childhood obesity.  相似文献   
9.
Some recent works suggest that extranodal atrial fibers may form part of the reenlry circuit in the atrioventricular (AV) nodal reentrant tachycardia (AVNRT). This hypothesis is based on the fact that the perinodal dissection successfully abolished AVNRT while preserving intact AV conduction. Apart from the surgical success, the electrophysiological evidence supporting this hypothesis has not been demonstrated, especially in the uncommon (fast-slow) form of AVNRT. We present some electrophysiological evidence suggesting atrial participation in eight patients with the fast-slow form of AVNRT. During the tachycardia, rapid pacing or extrastimulation was done from the orifice of the coronary sinus (CS) and the right atrium (RA), while recording the electrograms of the CS and the low septal RA. In seven patients, right and left atrial dissociation was demonstrated during pacing from the RA, while in the remaining one this was demonstrated from the CS. The interatrial dissociation will be unlikely if the intranodal reentry circuit connects with the atria via a single upper common pathway. This suggests that the upper turnaround of the reentry circuit involves atrial tissue and that the extranodal accessory pathway with long conduction times may form the ascending limb of the circuit (atrionodal reentry). Alternatively, the reentry circuit is entirely intranodal and two or more connecting pathways are present between the atria and the circuit.  相似文献   
10.
The neurotoxic effects of single subcutaneous injections of1000 mg triphenyl phosphite (TPP)/kg body weight were investigatedin White Leghorn hens. At 7 days postexposure, birds began toshow signs of mild to moderate ataxia that progressed to severeataxia and paralysis at 21 days. Inhibition of whole brain neuropathytarget esterase was 85% at 48 hr and 73% by 21 days postexposure.After postexposure periods of 7, 14, and 21 days, hens werekilled and their brains and spinal cords were examined for degeneratingaxons and terminals using the Fink-Heimer silver impregnationmethod. A small amount of degeneration was noted at 7 days.By 21 days, dense degeneration was noted in the spinal graymatter and funiculi. Degeneration was also present in the granularcell layer of cerebellar folia I-VI and in nuclei and fibertracts of the medulla. Moderate to dense degeneration was alsoseen in several forebrain and midbrain areas including the paleostriatum,ansa lenticularis, the dorsointermediate thalamic nucleus, lateralspiriform, pedunculopontine tegmental, and lateral mesencephalicnuclei and in the deeper layers of the optic tectum. These resultsindicate that, in addition to affecting the spinal cord andbrainstem, exposure to TPP also damages higher order centersresponsible for processing and integrating sensorimotor, visual,and auditory information.  相似文献   
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