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81.
Background and Aim: After hepatitis B virus (HBV) e antigen (HBeAg) seroconversion, HBV‐DNA continues to replicate, and HBeAg‐negative patients still face the risk of liver disease progression. We investigated the predictive factors for alanine aminotransferase (ALT) elevation, antiviral drug use, and hepatocellular carcinoma (HCC) occurrence in HBeAg‐negative patients. Methods: Age, sex, ALT, platelet counts, HBV‐DNA levels, genotype, antidiabetic drug use, body mass index, smoking, and alcohol consumption were analyzed for a total of 244 HBV carriers who were HBeAg‐negative. Results: Of 244 HBeAg‐negative patients, 158 (64.8%) showed normal ALT levels at baseline. Multivariate Cox hazard regression analysis identified high HBV‐DNA levels and high ALT at baseline as independent risk factors for ALT elevation in the patients with normal ALT at baseline. The threshold ALT and HBV‐DNA levels were determined to be 31 IU/L and 5.3 logcopies/mL, respectively. Seventeen (7.0%) patients used antiviral drugs. Multivariate Cox hazard regression analysis identified high HBV‐DNA levels (threshold, 5.7 log copies/mL), the use of antidiabetic drugs, and daily alcohol consumption at baseline as an independent risk factor for the use of antiviral drugs in HBeAg‐negative patients. In 10 patients (4.1%), HCC was detected, and a low platelet count (threshold, 10.0 × 104/mm3) was associated with the occurrence of HCC. Conclusion: This study identified predictors of future active liver disease in HBeAg‐negative patients, i.e. ALT elevation, unavoidable use of antiviral drugs, and occurrence of HCC.  相似文献   
82.
OBJECTIVES: Sixteen national surveys of Kawasaki disease in Japan from 1970 to 2000 have identified a total of 169,117 patients with Kawasaki disease. Based on that figure, 8,460 residents of Hokkaido probably have a history of Kawasaki disease. It is also estimated that almost 270 Hokkaido residents would have Kawasaki disease-related coronary artery disease. We underwent follow-up studies of Hokkaido residents > or = 15 years with Kawasaki disease. METHODS: We mailed a questionnaire to the departments of internal medicine, cardiology or cardiovascular surgery inquiring about the health status of patients with Kawasaki disease at 451 hospitals with 20 or more beds in Hokkaido. RESULTS: We obtained replies from 185 hospitals (41.0%). Only 11 hospitals(5.9%) reported experience of patients with Kawasaki disease(with or without coronary artery disease) at hospital follow-up. Detailed patient histories for 60 patients from 7 hospitals were obtained: Twenty patients had Kawasaki disease complicated with coronary artery disease, whereas 40 patients had a history of Kawasaki disease and no present coronary artery disease. Thirty-seven patients without coronary artery disease were followed up at one hospital. The 60 patients were aged from 15 to 36 years. Thirty-nine patients(65%) were in the 15 to 20 year age bracket. Coronary aneurysms were recognized in 25 patients(24 males and 1 female) with Kawasaki disease(41.7%) at the onset of the disease. Twenty patients had an aneurysm(s) in the left main trunk and/or the left anterior descending artery, and 13 patients in the right coronary artery. There was a history of myocardial infarction in four patients (6.7%) and nine patients(15.0%) still suffered from angina pectoris. Aortocoronary bypass surgery was performed in one patient, whereas two patients required percutaneous coronary intervention. CONCLUSIONS: Our study suggests that the majority of Hokkaido residents with Kawasaki disease(with or without coronary artery disease) are not being followed up at area hospitals. The characteristics of patients who were followed up included age < or = 20 years, male sex and the presence of severe coronary artery disease other than circumflex involvement.  相似文献   
83.
Neuronal cell death accounts for the clinical manifestations in Alzheimer's disease (AD). To establish the curative therapy of AD, neuroprotection is one of the primary therapeutic targets, and the elucidation of the mechanism of neuronal cell death is mandatory. Detailed characterization of neuronal cell death caused by familial AD (FAD)-linked mutant genes revealed that different cell death pathways are evoked by different types of mutants. Humanin (HN), a newly identified neuroprotective peptide, suppresses neuronal cell death caused by all known FAD mutants and A beta, while it has no effect on neuronal cell death caused by AD-irrelevant insults. The functional target of HN is the antagonism to neuronal death, not the modulation of A beta production, suggesting that HN-based medication can be combined with other remedies targeting A beta. HN is a promising seed for a novel therapy aiming at complete cure of AD through the suppression of neuronal loss.  相似文献   
84.
In skeletal muscle cells, voltage-dependent potentiation of Ca2+ channel activity requires phosphorylation by cAMP-dependent protein kinase (PKA) anchored via an A-kinase anchoring protein (AKAP15), and the most rapid sites of phosphorylation are located in the C-terminal domain. Surprisingly, the site of interaction of the complex of PKA and AKAP15 with the alpha1-subunit of Ca(V)1.1 channels lies in the distal C terminus, which is cleaved from the remainder of the channel by in vivo proteolytic processing. Here we report that the distal C terminus is noncovalently associated with the remainder of the channel via an interaction with a site in the proximal C-terminal domain when expressed as a separate protein in mammalian nonmuscle cells. Deletion mapping of the C terminus of the alpha1-subunit using the yeast two-hybrid assay revealed that a distal C-terminal peptide containing amino acids 1802-1841 specifically interacts with a region in the proximal C terminus containing amino acid residues 1556-1612. Analysis of the purified alpha1-subunit of Ca(V)1.1 channels from skeletal muscle by saturation sequencing of the intracellular peptides by tandem mass spectrometry identified the site of proteolytic processing as alanine 1664. Our results support the conclusion that a noncovalently associated complex of the alpha1-subunit truncated at A1664 with the proteolytically cleaved distal C-terminal domain, AKAP15, and PKA is the primary physiological form of Ca(V)1.1 channels in skeletal muscle cells.  相似文献   
85.
The type of leukemia was defined as HLA-DR(-) non-M3-AML, when HLA antigens were detected by flow cytometry at an incidence of < 20% of the blast population excluding M3-AML. Out of 109 patients with de novo acute myeloid leukemia, 8 patients had HLA-DR(-) non-AML-M3. According to the French-American-British criteria, 7 patients could be subdivided into 3 patients with M1, 4 patients with M2 and 1 patient with M4. The morphological features of bone marrow aspiration demonstrated no dysplasia and peroxidase stain positivity was noted in over 86% of the blast cells in all patients, the blast cells with fine granularity in 7 patients. The cytogenetic analysis revealed a normal karyotype. There was no expression marker of the blast antigens except CD13, CD14, CD33, CD34 and CD56. All of 7 patients who underwent induction therapy attained complete remission. Overall survival and disease-free survival showed no significant differences between the HLA-DR(-) non- M3-AML group and the HLA-DR(+) AML group.  相似文献   
86.
Cost-effectiveness analysis for the treatment of non-erosive reflux disease   总被引:1,自引:0,他引:1  
Non-erosive reflux disease(NERD) is a common condition and acid-suppressing agents are the mainstay of treatment. A cost-effectiveness analysis comparing a PPI, lansoprazole (LPZ) and a H2RA, ranitidine (RAN) for the treatment of NERD in Japan was performed using a decision analysis. The time period studied was one month and payer or patient' s perspective was considered. Efficacy data were estimated from a randomized clinical trial. Expected days without symptom (healthy days) were 20 for LPZ 15 mg/day and 16 for RAN 300 mg/day. Direct costs were 4,750 yen for LPZ and 4,358 yen for RAN. Cost-effectiveness ratio (direct costs/healthy days) was 238 yen for LPZ and 272 yen for RAN. Considering the results from a large-scale survey of GERD patients in Japan, the slightly higher price of LPZ was outweighed by its greater efficacy, also from the patient's willingness to pay perspective. Lansoprazole was superior to ranitidine with regard to both efficacy and cost-effectiveness and therefore is the preferred therapeutic agent for treatment of NERD.  相似文献   
87.
Morphological features of megakaryocytes were studied in 31 patients with myelodysplastic syndrome. Mean nuclear size (N), mean cytoplasmic size (C) and mean N/C ratio were 586 +/- 105 mu 2, 1,391 +/- 327 mu 2 and 0.42 +/- 0.04, respectively. Cell sizes were found to be reduced in 12 patients compared to control subjects. Atypical megakaryocytes were frequently found in patients with RAEB and micromegakaryocytes were also often found in patients with CMML. Mean platelet volume was 0.9 +/- 1.6 fl and the giant platelets were seen in one patient with CMML. In the patients with presence of more than 10% of atypical megakaryocytes, template Ivy bleeding time prolonged and epinephrine- and collagen-induced aggregation decreased. We believe that reduction of megakaryocytes' size and appearance of micromegakryocytes would be helpful in diagnosis of MDS.  相似文献   
88.
Here we report the generation and characterization of a monoclonal antibody, mAb 5H7-G1, which recognizes egg antigens in the animal cortex of fertilized, but not unfertilized, Xenopus eggs. The mAb 5H7-G1 was generated by subtractive immunization of mice: primary immunization with unfertilized egg extract followed by immunosuppression treatment with cyclophosphamide and repeated immunization with fertilized egg extract. In immunoblotting analysis, mAb 5H7-G1 recognizes multiple protein bands of fertilized (but not unfertilized or the ionophore-activated) Xenopus eggs. N-linked polysaccharide is most likely the target of mAb 5H7-G1 because immunoreactivity of mAb 5H7-G1 is effectively diminished when protein samples are treated with N-glycosidase F. Moreover, mAb 5H7-G1 recognizes some, but not all, tyrosine-phosphorylated proteins in eggs treated with H2O2, an artificial activator of the egg tyrosine kinase Src, suggesting that these proteins also contain N-linked sugars. When microinjected into fertilized Xenopus embryos, mAb 5H7-G1 causes a retardation or complete inhibition of first cell cleavage, suggesting that the mAb 5H7-G1-reactive antigens play an important role in this event. These results demonstrate that mAb 5H7-G1 is useful to analyze differential proteome display during fertilization and early development. More generally, subtractive immunization may work as a strategy to uncover cellular events that operate during different cellular conditions of interest.  相似文献   
89.
A HeLa cell line continuously expressing recombinant nucleoprotein (rNP) of the Crimean-Congo hemorrhagic fever virus (CCHFV) was established by transfection with an expression vector containing the cDNA of CCHFV NP (pKS336-CCHFV-NP). These cells were used as antigens for indirect immunofluorescence (IF) to detect immunoglobulin G antibodies to CCHFV. The sensitivity and specificity of this IF technique were examined by using serum samples and were compared to those of the IF technique using CCHFV-infected Vero E6 cells (authentic antigen). Staining of the CCHFV rNP expressed in HeLa cells showed a unique granular pattern similar to that of CCHFV-infected Vero E6 cells. Positive staining could easily be distinguished from a negative result. All 13 serum samples determined to be positive by using the authentic antigen were also determined to be positive by using CCHFV rNP-expressing HeLa cells (recombinant antigen). The 108 serum samples determined to be negative by using the authentic antigen were also determined to be negative by using the recombinant antigen. Thus, both the sensitivity and the specificity of this IF technique were 100% compared to the IF with authentic antigen. The novel IF technique using CCHFV rNP-expressing HeLa cells can be used not only for diagnosis of CCHF but also for epidemiological studies on CCHFV infections.  相似文献   
90.
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