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Continuous-flow left ventricular assist devices (LVADs) provide acceptable clinical results, but the long waiting period for heart transplantation leads to diverse complications. LVAD support can cause reverse left ventricular (LV) remodeling that results in the improvement of LV function and allows LVAD removal. We present a case of successful removal of a DuraHeart LVAD because of sufficient recovery of LV function. Before LVAD removal, we conducted an “LVAD weaning test” by decreasing pump speed and performing an additional normal saline infusion test. We consider that the LVAD weaning test can be used in place of the “pulsatile LVAD off test.”  相似文献   
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Regulation of nuclear retention of glucocorticoid receptor by nuclear Hsp90   总被引:3,自引:0,他引:3  
Heat shock protein 90 (Hsp90) has been demonstrated in both cytoplasm and nucleus, and regulates cytoplasmic retention of glucocorticoid receptor (GR). However, the role of nuclear Hsp90 in GR trafficking is less characterized. The present study examined the role of Hsp90 in nuclear retention of GR after ligand withdrawal. Hsp90 inhibitors; geldanamycin (GA) and radicicol (Rad), significantly accelerated nuclear export of GR after withdrawal of ligands including dexamethasone, corticosterone and RU486. GA accelerated relocalization of GR in the cytoplasm even when reimport of GR into the nucleus was inhibited by okadaic acid or when novel GR synthesis was inhibited by cycloheximide. Overexpression of wild type or nuclear-targeted Hsp90 attenuated Hsp90 inhibitor-induced acceleration of GR nuclear export, although nuclear Hsp90 showed higher activity than the wild type. Only nuclear-targeted Hsp90 prolonged basal nuclear retention of GR after withdrawal of dexamethasone and corticosterone. These results suggest that nuclear Hsp90 regulates the nuclear retention of GR.  相似文献   
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Amyopathic dermatomyositis (ADM) is a clinical subtype of dermatomyositis, characterized by the lack of motor weakness and the presence of normal muscle enzyme levels. ADM is sometimes accompanied by interstitial pneumonia that shows a rapid progressive course associated with a poor prognosis. We report a 49-year-old patient who presented with nonspecific interstitial pneumonia (NSIP) associated with ADM. The patient failed to respond to prednisolone and immunosuppressive therapy and died. Although idiopathic NSIP is known to have a better prognosis, NSIP in ADM could be a fatal disease. Therefore, we should appropriately treat interstitial pneumonia in ADM even if it is NSIP.  相似文献   
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Anti-von Willebrand factor (vWF) monoclonal antibody NMC-4 completely inhibited vWF binding to platelet glycoprotein (GP) lb induced by either ristocetin or botrocetin at an IgG concentration of approximately 10 micrograms/mL, and also blocked binding of asialo-vWF to GP lb. NMC-4 coupled beads isolated a 97-Kd fragment (Fr) from a whole tryptic digest of vWF. The N-terminal sequencing of the nonreduced 97-Kd Fr, in combination with amino acid analysis, showed it to be a homodimer of residues 449 through 728 of the constituent subunit. Present data, together with the results obtained from previous studies, confirm the existence of one or three possible inter-subunit disulfide bonds between cysteine residues 459, 462, and 464. NMC-4 bound to reduced vWF Fr(s) more weakly than to nonreduced Fr(s), but it did not react with Fr III-T2 of vWF, a disulfide-linked twin heterodimer of residues 273 through 511 and 674 through 728 (Marti et al, Biochemistry 26:8099, 1987). Fr III-T2 completely inhibited ristocetin-induced vWF binding at a concentration of 100 mumol/L but had no effect on botrocetin-induced binding. In addition, both the N- and C-terminal polypeptides, residues 449 through 549 and 674 through 728, generated by subdigestion of the 52/48-Kd Fr (Fujimura et al, J Biol Chem 261:381, 1986), inhibited preferentially ristocetin-induced vWF binding without affecting to botrocetin-induced vWF binding. These findings suggest that amino acid residues 512 through 673 of the vWF subunit are involved in botrocetin-induced vWF binding.  相似文献   
99.
Factors predicting the efficacy of interferon therapy were statistically analyzed on 111 patients with chronic hepatitis C. Of the treated patients (total doses of interferon; 96–468 MU), 35 (31.5%) had a long-term remission. On multivariate analysis, hepatitis C virus genotype (p<0.0001), histological diagnosis (p<0.05), fibrosis score of histological activity index (p<0.01) and source of infection (p<0.05) were found useful for predicting the response to interferon therapy. Our findings suggest that the outcome of interferon therapy can be predicted to some degree from pretreatment data, and that a new therapeutic strategy is necessary for the group of patients who are predicted to be nonresponders.  相似文献   
100.
Background and objectives: The aim was to produce HBcAg from plants more cheaply than can be done by other currently available means, and to apply such antigen to immunoassay procedures for pretransfusion testing of donor blood. Materials and methods: Transgenic Nicotiana tabacum cv. SR-1 plants expressing the human hepatitis B virus (HBV) core antigen (HBcAg) gene were generated by Agrobacterium-mediated transformation. The recombinant product, called tHBcAg, can assemble itself into a spherical particle with a diameter of 25 to 30 nm, and can maintain two antigenic determinants of HBcAg, namely HBc/α and HBc/β. Partly purified tHBcAg was used in the hemagglutinationinhibition (HI) test, as routinely used by the Japanese Blood Center, to test a panel of 524 blood units taken from HBV-positive donors. Results: In the HI test, tHBcAg showed serologic properties comparable to that from Escherichia coli, the standard antigen used in the Japanese Blood Center. Conclusions: Transgenic plants can produce reagents for serologic testing and perhaps even such medical materials as oral vaccines.  相似文献   
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