Application of AlGaAs/GaAs HBTs for wideband direct-coupled amplifiers

An AlGaAs/GaAs HBT direct-coupled amplifier has been designed and its characteristics described for the first time. The amplifier consists of two HBTs and three resistors without level-shift diodes. A superior amplifier performance of 11 dB gain with a 4 GHz bandwidth was obtained.     

Autocrine/paracrine role of adrenomedullin in cultured endothelial and mesangial cells

Neuropsychological profiles were assessed in a large group of nondemented control subjects (n = 261) and individuals with dementia of the Alzheimer type (DAT) (n = 407) by subjecting their psychometric test results to a factor analysis. Nondemented control subjects were functionally homogeneous with only one factor accounting for the results. The results of the factor analysis on the very mild DAT and mild DAT groups, however, yielded a mental control/frontal factor, a memory-verbal/temporal factor, and a visuospatial/parietal factor. Forty-one of the original set of participants came to autopsy an average of 5.1 years after psychometric testing and had neurofibrillary tangles, total senile plaques, and cored senile plaques estimated from frontal, temporal, and parietal regions. The results of correlations indicated that the relative burden of cored senile plaques was systematically related to the three psychometric factors. These results suggest a connection between the specific functions as defined by neuropsychological measures and specific neuropathology occurring in associated areas of cortex.     

Analysis of T-cell receptor beta of the T-cell clones reactive to the human PDC-E2 163-176 peptide in the context of HLA-DR53 in patients with primary biliary cirrhosis

T-cell-mediated autoimmune mechanisms are considered to be involved in the pathogenesis of primary biliary cirrhosis (PBC). In the previous study, we identified the immunodominant T-cell epitope on the E2 component of pyruvate dehydrogenase complex (PDC-E2) in patients with PBC who have HLA-DRB4*0101. In this report, we revealed that the frequency of the T cells reactive to the human PDC-E2 163-176 peptide is significantly increased in the peripheral blood of patients with PBC as compared with healthy subjects. We also confirmed that these T cells were all restricted with HLA-DRB4*01 (DR53) by using HLA-DR-transfected L cells. These results together with the evidence that the immunodominant B-cell epitope overlaps with the human T-cell epitope of the PDC-E2 antigen indicate that the T cells reactive to this epitope are closely associated with the pathogenesis of PBC at least in patients who have HLA-DR53. Therefore, we analyzed the T-cell receptor (TCR) Vbeta sequence of the five different T-cell clones and the three T-cell clones derived from three patients with PBC and healthy subjects, respectively, which are reactive to the human PDC-E2 163-176 peptide in the context of HLA-DR53. The Vbeta- and the Jbeta-gene usages were diverse among the T-cell clones (Vbeta11-Jbeta1.4, Vbeta8-Jbeta1.2, Vbeta12-Jbeta2.1, Vbeta10-Jbeta1.5, and Vbeta20-Jbeta2.1) in patients with PBC. By contrast, in the third complementarity determining region (CDR3), G was frequently found and GXG or GXS motif was identified in all T-cell clones. Moreover, RGXG motif was found in three clones generated from two patients. In healthy subjects, the Vbeta- and the Jbeta-gene usages were also diverse, and GXG and RGXG motif were found. These results indicate that the T cells may recognize the ligand (the human PDC-E2 163-176 peptide/HLA-DR53 complex) using the limited motif in the CDR3 region and that the design of CDR3-specific immunotherapy would be possible using these motifs.     

Neoadjuvant intra-arterial chemotherapy based on chemosensitivity tests for locally invasive bladder cancer

We investigated the clinical usefulness of individualization of chemotherapeutic regimen in neoadjuvant intra-arterial chemotherapy for locally invasive bladder cancer. Anticancer drugs were selected according to the results of an in vitro chemosensitivity test (collagen matrix assay or succinic dehydrogenase inhibition test). Nine patients with locally invasive bladder cancer received 1 to 4 courses of neoadjuvant intra-arterial chemotherapy, followed by radical cystectomy. Histopathological responses in the cystectomized specimens were grade 3 in 3 cases, grade 2 in 2, grade 1b in 2 and no response in 2. Pathologically, a complete response and downstaging were observed in 3 and 4 cases, respectively. Seven of the 9 patients were alive no evidence of disease with a mean follow-up period of 38.9 months, whereas 2 patients died of metastasis within 2 years. Six of the 7 patients who showed a complete response or down staging have been free of recurrence. These findings suggest that our chemotherapeutic strategy may improve the prognosis for locally invasive bladder cancer.     

Apolipoprotein E polymorphism is associated with plasma cholesterol response in a 7-day hospitalization study for metabolic and dietary control in NIDDM

An 81-year-old woman in whom liver dysfunction had been pointed out 3 years previously was diagnosed as having liver cirrhosis due to lupoid hepatitis. Considering the poor prognosis of cirrhosis and her age, immunosuppressive therapy was not adopted. Nine months later, a small liver tumor was found by ultrasonography and was diagnosed as hepatocellular carcinoma (HCC). The tumor was treated with transcatheter arterial embolization, but grew continuously. She also developed gingival lymphoma that was successfully treated. Three years after initial diagnosis of lupoid hepatitis, she died of hepatic failure. An autopsy was performed and confirmed the clinical diagnosis, liver cirrhosis with HCC. HCC is regarded as a rare complication of lupoid hepatitis, but cases of HCC complicating lupoid hepatitis may increase with progress in treatment methods and elongation of survival. The present case suggests that any malignancy can be developed in long-term surviving patients with lupoid hepatitis.     

Interferon therapy after ablation of Kent bundle for a patient with chronic hepatitis type B complicated with WPW syndrome

Cardiotoxicity of interferon-alpha or gamma, such as fatal arrhythmia and myocardial infarction, has been reported. Therefore cardiotoxicity of interferon should be seriously considered before administration for patients with a pre-existing heart disease. We treated a patient with chronic active hepatitis type B, coexisted with Wolff-Parkinson-White syndrome, who has had frequent attacks of paroxysmal atrial fibrillation. To prevent the occurrence of fatal arrhythmia with an interferon therapy in this patient, we performed radiofrequency catheter ablation of the Kent bundle. After the successful ablation, we could safely administered recombinant interferon alpha-2b for chronic hepatitis type B.     

Inhibitory effect of vitamin E succinate on the proliferation of cultured bovine choroidal endothelial cells

We report the effect of vitamin E succinate (VE succinate) on the proliferation of cultured bovine choroidal endothelial cells (BCECs). BCECs were incubated with a medium containing vitamin E (VE) or one of the VE derivatives gamma-tocopherol, VE phosphate, VE succinate, VE nicotinate, VE acetate, or trolox, at a concentration of 10 microM. The proliferation of BCECs was assessed by 3H-thymidine uptake and cell counting. Especially in VE and VE succinate, the proliferation assay was performed on BCECs at two different stages, that is, the proliferating stage and the quiescent stage. The effect of protein kinase C (PKC) stimulator phorbol ester (PMA) on the VE succinate-induced inhibition of BCEC proliferation was also examined. VE succinate was found to significantly inhibit BCEC proliferation at a concentration of 10 microM or greater both by 3H-thymidine uptake assay and by cell counting. This inhibitory effect was not noted in other VE derivatives. The inhibitory effect was the most prominent in the proliferating BCECs and co culture of PMA. VE succinate inhibits the proliferation of cultured BCECs and PKC is involved in this action at least in part.