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Notes: Abstract High-power electrostatic microactuators using LIGA process have been fabricated. Comb drive type actuators and a wobble motor were designed and fabricated. A basic structure of the microactuators was composed of movable and fixed electrodes of Ni, a sacrificial layer of SiO2 and a Si substrate, and carried out by one mask process. As design rules, a minimum resist width of 2 μm, resist height of 120 μm, maximum width of movable parts of 10 μm, minimum width of fixed parts of 40 μm and driving voltage of about 100 V, were decided. A 120 μm-thick PMMA resist was formed on a Si substrate by a casting method. The PMMA was exposed using a compact SR source “AURORA”, using an X-ray mask with 7 μm-thick Au absorber on a 2 μm-thick poly-Si membrane. The exposed PMMA was developed by a developer. Ni microstructures with 100 μm-height, 2 μm-minimum width, 2 μm-minimum gap, and then maximum aspect ratio of 50, were made by electroforming. Ni microstructures used for movable electrodes were separated from the substrate by lateral etching of SiO2. After lateral etching of SiO2, Au wires were bonded to electrodes. Actuation of the comb drive type actuator and rotation of the wobble motor were confirmed. The applied voltage to the comb drive actuator and the wobble motor were 65 and 125 V.

Notes: : :Suitability of the dielectric constant for real time and continuous evaluation of frying oil was investigated. Measurements of the dielectric capacitance, in the frequency range 1 kHz to 100 kHz, were made on soybean oil heated at several temperatures (180, 200, 220, and 240 °C) for a few d. Frequency dependence was also measured between 50 Hz and 30 MHz. The dielectric constant of the soybean oil increased with increase in the heating time, and was well correlated with acid value, density, and relative viscosity. Our equipment for measuring capacitance would be available for real time and continuous evaluation of frying oil quality in the food industry.

Notes: In the alternating current plasma display panel, a widespread discharge can take place accidentally in a large number of cells in the upper or lower panel ends. The undesirable discharge is referred to as global breakdown. This is a serious problem, with consequences not only for display quality, but also for product reliability. The mechanism of the global breakdown was examined experimentally using a surface electrometer and theoretically using plasma simulation. From these examinations, the global breakdown mechanism was clarified as follows. Global breakdown was accompanied by charge separation in the horizontal direction of the panel. This charge separation was caused by electron transport downward in the panel during the address discharge. The electron transport formed a negative wall charge on the phosphor surface. When the wall voltage exceeded the insulation voltage of the protective layer, global breakdown occurred. Furthermore, it was clarified that increasing the front dielectric thickness or reducing the back dielectric thickness could suppress the electron transport during the address discharge. These optimizations of cell geometry could eliminate the global breakdown. © 2001 American Institute of Physics.

Notes: 1. We investigated the effect of intermittent exposure to hypobaric hypoxia on the ability of neutrophils to generate ·O2–.2. Seven male volunteers were exposed intermittently to hypobaric hypoxia, equivalent to an altitude of 4500 m, for 7 successive days. Peripheral blood samples were collected before and after the 2 h course of hypobaric hypoxia on days 1 and 7 and neutrophils were subjected to a chemiluminescence assay for ·O2– production.3. On day 1, 2 h exposure to hypobaric hypoxia induced granulocytosis (P 〈 0.01), but the ability of neutrophils to generate ·O2– was unchanged.4. On day 7, such granulocytosis was not observed, suggesting acclimatization to hypobaric hypoxia.5. The ability of neutrophils to generate ·O2– was significantly increased on day 7 (P 〈 0.01), although there was no definite change in the mRNA expression of NADPH oxidase subunits in the cells.6. The results suggest that the ability of neutrophils to generate ·O2– may be gradually potentiated by intermittent exposure to hypobaric hypoxia, even after the number of neutrophils in peripheral blood stabilizes.

Notes: Background: Incidental IgA deposition in glomerular mesangium exists in 10–20% of autopsy kidneys1,2 or renal allograft donors.3 In the present study, we examined the clinicopathological features of incidental mesangial IgA deposition in renal biopsy from patients with minimal change nephrotic syndrome (MCNS) to understand the significance of mesangial IgA deposition in MCNS and pathogenesis of IgA nephropathy.Patients and Methods: From January 1994 to September 2000, 63 patients were diagnosed with MCNS by renal biopsy at Kidney Center, Tokyo Women’s Medical University. Mesangial IgA and C3 deposition was examined by immunofluorescence staining using frozen sections. The frequency of IgA and C3 deposition in MCNS and clinicopathological features of IgA-positive patients with MCNS were investigated.Results: The mesangial IgA deposition was present in 15 out of 63 patients (23.8%). Among these 15 patients, codeposition of C3 was present in 10 patients (66.7%) (〈link href="#f1"〉Fig. 1). The serum IgA concentration was significantly higher in the IgA-positive patients than in the IgA-negative patients (309 ± 75 mg/dL versus 245 ± 106 mg/dL, P = 0.043) (〈link href="#f2"〉Fig. 2). The urinary red blood cell count was higher in IgA-positive patients than in IgA-negative patients, although not significantly different (11.7 ± 12.7 counts/HPF versus 5.3 ± 4.0 counts/HPF, P = 0.067) (〈link href="#f3"〉Fig. 3). Other clinical parameters (age, sex, amount of proteinuria, serum creatinine and creatinine clearance) were not significantly different. Histologically, no significant differences were observed between IgA-positive and IgA-negative patients in following parameters: grade of mesangial cell proliferation and mesangial matrix increase, extents of tubular atrophy and interstitial fibrosis and grade of vascular sclerosis. After steroid treatment, all 15 patients with mesangial IgA deposition had become complete remission, although three patients once relapsed proteinuria. The haematuria also disappeared after steroid treatment in these patients.〈figure xml:id="f1"〉1〈mediaResource alt="image" href="urn:x-wiley:13205358:NEP14:NEP_14_f1"/〉The frequency of mesangial IgA and C3 deposition in MCNS patients (n = 63). The mesangial IgA deposition was present in 15 out of 63 patients (23.8%). Among these 15 patients, codeposition of C3 was present in 10 patients (66.7%).〈figure xml:id="f2"〉2〈mediaResource alt="image" href="urn:x-wiley:13205358:NEP14:NEP_14_f2"/〉The serum IgA concentration of the MCNS patients with and without mesangial IgA deposition. The serum IgA concentration was significantly higher in IgA-positive patients (n = 15) than in IgA-negative patients (n = 48) (309 ± 75 mg/dL vs 245 ± 106 mg/dL, P = 0.043).〈figure xml:id="f3"〉3〈mediaResource alt="image" href="urn:x-wiley:13205358:NEP14:NEP_14_f3"/〉The urinary red blood cell counts of the MCNS patients with and without mesangial IgA deposition. The urinary red blood cell count was higher in IgA-positive patients (n = 15) than in IgA-negative patients (n = 48), although not significantly different (11.7 ± 12.7 counts/HPF vs 5.3 ± 4.0 counts/HPF, P = 0.067).Conclusion: The incidental mesangial IgA deposition was frequently observed in MCNS patients (15/60 patients, 23.8%). The phenomenon of mesangial IgA deposition in MCNS patients was related to higher serum IgA concentration and might cause slight haematuria. However, no influence of mesangial IgA deposition was found on the renal function and the clinical outcome of MCNS after treatment.

Notes: Background Food allergies are more prevalent in children, due to the immature gastrointestinal epithelial membrane barrier allowing more proteins through the barrier and into circulation. Ovomucoid (OM) is one of the major allergens that is found in egg white.Objective The aim of this study was to determine T cell epitopes, antigen-presenting human leucocyte antigen (HLA) class II molecules of the T cell lines (TCLs) and T cell clones (TCCs), and complementarity determining region (CDR) 3 loops of the T cell receptor (TCR) α and β chains of the TCCs specific to OM.Methods We established TCLs and TCCs specific to OM from peripheral blood mononuclear cells (PBMCs) of four atopic patients with egg-white allergy using a mixture of a panel of overlapping synthetic peptides corresponding to the amino acid sequence of the entire OM. We identified the T cell epitopes by antigen-induced proliferative responses, antigen-presenting molecules using allogeneic PBMCs and CDR3 loops of the TCR α and β chains by cloning and sequence analysis.Results The TCLs and TCCs responded to seven different peptides, and their antigen-presenting molecules were different from each other. Sequence analysis of the TCR α and β gene usage of the TCCs showed marked heterogeneity, and the usage of the CDR3 loop of the TCCs involved heterogenous amino acid residues. Interestingly, TCCs ‘IH3.3’ and ‘YT6.1’ recognized the same OM peptides, and had the same TCR Vβ-Jβ gene usage. Considering that peptide motifs bind to HLA class II molecules, the electrically charged residue (positive or negative) on the CDR3α and the CDR3β loops of TCR of TCC may form ionic bonds with a charged residue on the HLA class II molecules-peptide complex.Conclusions TCCs that have the same TCR gene usage were established from patients who had shown similar hypersensitivity-type, indicating that antigen recognition by a specific TCR is closely associated with the characteristics of each patient's symptoms.

Notes: Background The hypertrophy/hyperplasia of airway smooth muscle (ASM) cells is one of the characteristic features of bronchial asthma. This structural change leads to the thickening of airway walls resulting in the amplification of airway narrowing. However, the pathogenesis of this structural change has not yet been determined. Eosinophils, which play a pathogenic role in asthma, have been demonstrated to have proliferative effects on fibroblasts and vascular smooth muscle cells.Objective We attempted to investigate the potential of eosinophils to induce the proliferation of ASM cells.Methods We examined the effect of lysates of eosinophils purified from peripheral blood of healthy donors on cultured human ASM cell proliferation.Results Eosinophil lysates significantly induced ASM cell proliferation in time- and dose-dependent manners, reaching a maximum on day 6 at 50% of eosinophil lysates (6.0 ± 0.7 × 104[mean ± SD] /well, n = 5 vs. 4.5 ± 1.1 × 104/well, n = 5; P 〈 0.05). This proliferative activity was heat-sensitive and recovered in the soluble fraction of the eosinophil lysates. Furthermore, the molecular weight of the mitogenic activity in the soluble fraction was identified as lower than 10 kDa. The inhibitory activity to ASM cell proliferation was also found in the insoluble fraction of the lysates.Conclusion These results indicate that circulating eosinophils store mitogenic activity for ASM cells, suggesting that eosinophils might contribute to the development of the hyperplasia of ASM cells in asthmatics through the release of the stored mitogenic activity upon stimulation at the site of inflammation.

Notes: Background Allergic individuals respond to only a few specific antigens, therefore allergic diseases are characterized by antigen specificity. Clarification of the mechanism of antigen specificity will lead to progress in the therapy of allergic diseases.Objectives The purpose of this study is to determine the specific association among T cell epitopes, antigen-presenting molecules and T cell receptor (TCR), and to determine the TCR usage in the pathogenesis of allergies using antigen-specific T cell clones (TCCs). The results can clarify the mechanism of the antigen specificity of allergic diseases, and provide new therapeutic possibilities using analogue peptides.Methods Short-term T cell clones specific to β-lactoglobulin (BLG) were established from peripheral blood mononuclear cells (PBMCs) collected from five patients allergic to cow's milk. We then identified the T cell epitopes and antigen-presenting molecules, and examined TCR usage. We also determined the sequence of the TCR-complementarity-determining region 3 (CDR3).Results Six TCCs established from the five patients recognized three different peptides, and BLGp97–117 was recognized by four of the six TCCs. BLGp101–112 (KYLLFCMENSAE) was the core sequence in the fragment. Sequence analysis of TCR by the RT-PCR method revealed a marked heterogeneity in TCR usage, and similar amino acid sequences were recognized in the CDR3 region. Four of the six TCCs recognized BLG in association with human leucocyte antigen (HLA)-DRB1*0405 as antigen-presenting molecules.Conclusion We proposed the motif of the interaction between the HLA-DRB1*0405 allele and antigen peptide, and suggested that HLA-DRB1*0405 is an immunoregulatory gene product for T cell responses to BLG.

Notes: Background Eosinophilic tracheobronchitis with cough hypersensitivity, abbreviated as atopic cough, is an important cause of chronic cough. The reason for the absence of airway hyper-responsiveness is unknown, differing from asthma, a Th2 cytokine-mediated disorder.Objective To compare the type 1 helper T cell (Th1)/Th2 balance in the peripheral blood from subjects with atopic cough and atopic asthma, we assessed the intracellular cytokine production at the single-cell level.Methods Thirty-six subjects (10 patients with atopic cough, 18 with atopic asthma, and eight control subjects) were included. Intracellular IL-4 and IFN-γ were detected in CD4+ T cells by flow cytometry.Results A significantly lower ratio of IFN-γ-/IL-4-producing CD4+ T cells after phorbol 12-myristate acetate/ionomycin stimulation was found in patients with atopic cough and atopic asthma compared with normal subjects. In comparison between atopic patients, the ratio of IFN-γ-/IL-4-producing cells was significantly higher in atopic cough than in atopic asthma. However, the proportion of IL-4-producing CD4+ T cells was significantly higher in patients with atopic asthma than in normal control subjects and no significant difference was detected between patients with atopic cough and normal subjects. No significant difference in the proportion of IFN-γ-producing cells was found between the subjects. Overall, the total IgE levels were positively correlated to the IL-4-producing cells and inversely correlated to the ratio of IFN-γ-/IL-4-producing cells.Conclusion These results show the lower degree of Th2 cytokine predominance in atopic cough compared with atopic asthma and suggest the relation between the Th1/Th2 balance and atopic status.

Notes: Regulation of fluoride release from restorative resin or sealant is beneficial to patients as it will prevent the occurrence of the secondary caries. In this study, we evaluated whether or not the formation of a hydrophobic polysiloxane layer on the surface of the fluoride compound could contribute to the regulation of fluoride release from resin. First, sodium hexafluorosilicate (Na2SiF6) powder was treated with γ-methacryloxypropyltrimethoxysilane (γ-MPTS) and analysed with scanning electronmicroscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and electron spectroscopy for chemical analysis (ESCA). Analysis revealed that a hydrophobic polysiloxane layer was formed on the surface of Na2SiF6 powder. Heat treatment commonly used during γ-MPTS treatment was not necessary for the polysiloxane layer formation on the surface of Na2SiF6 powder. Then Na2SiF6 powder treated with γ-MPTS was loaded in bis-GMA/TEGDMA resin, immersed in distilled water and fluoride release was measured using a fluoride electrode. We found that the rate of fluoride release was significantly lower from the resin containing Na2SiF6 powder treated with c-MPTS. We concluded, therefore, that c-MPTS treatment and the resulting hydrophobic polysiloxane layer formation are very effective for the regulation of fluoride release from resin.