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PURPOSE: We studied the sonographic appearance of the anterior liver surface using an ultrasound scanner equipped with a 7.5-MHz annular-array transducer to determine the accuracy of this imaging modality in monitoring the course of chronic liver diseases. METHODS: We prospectively evaluated patterns of the liver surface in the sonograms of 77 consecutive patients with chronic liver diseases who had undergone sonographic examination with a 7.5-MHz annular-array transducer and a 3.75-MHz convex-array transducer over a 2-year period and compared these findings with those of laparoscopy (using previously described categories) and histopathology. RESULTS: Histopathologically confirmed disease prevalences for inactive chronic hepatitis, active chronic hepatitis, liver cirrhosis, and others were 10% (8/77), 56% (43/77), 29% (22/77), and 5% (4/77), respectively. The sonographic appearance of the liver surface with the 3.75-MHz transducer was classified as either a regular or an irregular pattern. The regular pattern corresponded to 69% (34/50) of the cases in laparoscopic category 200 or 300 and the irregular pattern with 85% (23/27) of the cases in category 400 or 500. The sonographic appearance of the liver surface with the 7.5-MHz transducer was classified as regular, unevenly irregular, diffusely irregular, or nodular. These 4 patterns detected 75% (24/32), 78% (14/18), 52% (12/23), and 75% (3/4) of the cases of laparoscopic categories 200, 300, 400, and 500, respectively. In a comparison of the sonographic patterns of the liver surface with the differential histopathologic findings, the regular sonographic pattern corresponded to 88% (7/8) of the cases of inactive chronic hepatitis, the unevenly irregular pattern with 35% (15/43) of the cases of active chronic hepatitis, and the diffusely irregular and nodular patterns (considered as 1 group) with 68% (15/22) of the cases of liver cirrhosis. CONCLUSIONS: Our results suggest that sonographic evaluation of the liver surface with a 7.5-MHz annular-array transducer using this classification provides detailed information on the evolution of chronic liver diseases that correlates with the laparoscopic and histopathologic findings and thus is a useful noninvasive method for monitoring the disease course to cirrhosis.  相似文献   
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Accumulating evidence has revealed pivotal roles of glycogen synthase kinase-3β (GSK3β) inactivation on cardiac protection. Because the precise mechanisms of cardiac protection against ischemia/reperfusion (I/R) injury by GSK3β-inactivation remain elusive, we investigated the relationship between GSK3β-mediated mitochondrial hexokinase II (mitoHK-II; a downstream target of GSK3β) dissociation and mitochondrial permeability transition pore (mPTP) opening. In Langendorff-perfused hearts, GSK3β inactivation by SB216763 improved the left ventricular-developed pressure and retained mitoHK-II binding after I/R. In permeabilized myocytes, GSK3β depolarized mitochondrial membrane potential with accelerated mitochondrial calcein release (suggesting GSK3β-mediated mPTP opening) and decreased mitoHK-II bindings. GSK3β-mediated mPTP opening depended on mitoHK-II binding, i.e., it was accelerated by dissociation of mitoHK-II (dicyclohexylcarbodiimide) and attenuated by enhancement of mitoHK-II binding (dextran). However, inactivation of mitoHK-II by glucose-depletion or glucose-6-phosphate inhibited the GSK3β-mediated mPTP opening. We conclude that GSK3β-mediated mPTP opening may be involved in I/R injury and regulated by mitoHK-II binding and activity.  相似文献   
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We investigated the therapeutic effect of zonisamide against 1-methyl-4-phenyl- 1,2,3,6-tetrahydropyridine (MPTP) neurotoxicity in mice, using Western blot analysis, immunohistochemistry and behavioral test. Our Western blot analysis and immunohistochemical study showed that the post-treatment with zonisamide prevented significantly dopaminergic cell damage, the depletion of tyrosine-hydroxylase (TH) protein levels and the proliferation of microglia in the striatum and/or substantia nigra 8 days after MPTP treatment. Furthermore, our behavioral study showed that the post-treatment with zonisamide attenuated significantly the motor deficits 7 days after MPTP treatment. These results show that zonisamide has the therapeutic effect in the MPTP model of Parkinson’s disease (PD) in mice. Our study also demonstrates the neuroprotective effect of zonisamide against dopaminergic cell damage after MPTP treatment in mice. Thus our present findings suggest that therapeutic strategies targeted to the activation of TH protein and/or the inhibition of microglial activation with zonisamide may offer a great potential for restoring the functional capacity of the surviving dopaminergic neurons in individuals affected with PD.  相似文献   
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We developed a novel ultrarapid immunohistochemical staining method in which an AC electric field is used to facilitate detection of tumor cells. Frozen sections of non-small cell lung cancer in lymph nodes were fixed in acetone for 2 min, after which they were incubated for 2 min with an anti-pancytokeratin antibody cocktail and then with EnVision(TM) complex under an alternating current (AC) electric field. The sections were then incubated with a chromogen (3,3'diaminobenzidine) for 3 min and counterstained with hematoxylin. This method enabled detection of tumor cells in frozen sections in less than 15 min. In addition, we were able to reduce the amount of antibody used by more than 90% when the sections were incubated under the AC electric field for a longer period. This method could be a useful tool for frozen section diagnosis and research. Furthermore, with this method the cost of immunohistochemical staining can be reduced.  相似文献   
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Anti-CD20 antibody (rituximab) is recently being used as a B cell-depleting agent in renal transplantation (RTx). However, the incidence of infectious complications associated with rituximab therapy remains uncertain. We evaluated the incidence of cytomegalovirus (CMV) infection associated with rituximab therapy in RTx. A total of 83 patients were enrolled. The immunosuppressive regimen consisted of tacrolimus or cyclosporin, mycophenolate mofetil, methylprednisolone and basiliximab. In 54 patients, only one dose of rituximab (200 or 500 mg/kg body weight) was given before RTx. A total of 25 of 43 (58.1%) recipients who were CMV seropositive prior to RTx and who received rituximab induction therapy developed CMV infection, compared to 18 of 24 (75%) CMV seropositive recipients who did not receive rituximab therapy ( P  = 0.1676). A total of 8 of 11 patients who were CMV seronegative prior to RTx and who received rituximab developed CMV infection. However, CMV seroconversion was seen in all 8 of these infected patients. Low-dose rituximab induction therapy in renal transplant recipients appears to have no influence on the incidence of CMV infection and CMV seroconversion. However, we have to consider anti-CMV prophylaxis therapy, because of high incidents of CMV infection, especially for CMV seronegative recipients who received rituximab.  相似文献   
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