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Notes: A hydrogen beam probing system developed for the REPUTE-1 reversed field pinch device is described. With this system, the plasma ion line density, the central ion temperature, and the magnetic field profile can be measured. Before being applied to the REPUTE-1 device, the probing system was tested on the TORIUT-5 tokamak and TORIUT-6 ultralow-q (ULQ) devices. The experimental results show the availability of the system. The measured line density agrees well with that measured by the microwave interferometry. The measurable density ranges from 1019 m−3 to 3×1020 m−3. A new method of magnetic field measurement which is effective and important for RFP plasmas is proposed. The resolution and the accuracy of this measurement have been confirmed by experiments on the TORIUT-5 device. Experimental results agree well with computation.

Notes: The aim of the present study was to examine the role of CD28-B7 signalling in the development of glomerulonephritis in ddY mice, an animal model for IgA nephropathy. To achieve this aim, we investigated whether the CTLA-4 (CD152) fusion protein, which binds to B7.1 (CD80) and B7.2 (CD86), affects glomerular pathological changes (including IgA deposition), or functional parameters (such as serum creatinine and proteinuria). Each group (n = 4) was given either human CTLA-4 fused with human IgG (CTLA4Ig) or control human IgG1. All treated groups of mice were injected intraperitoneally at a dose of 0.1 mg twice a week for the duration of the study. Mice given control human IgG1 progressively developed typical mesangioproliferative glomerulonephritis, with remarkable glomerular IgA deposits. In contrast, mice treated with CTLA4Ig showed a significant reduction in proteinuria and mesangioproliferative change, with an expansion of the mesangial matrix at 40 weeks of age. The serum IgA levels of these mice were considerably lower than those in mice given the control human IgG1. A direct immunofluorescence study showed the reduction of glomerular IgA deposits in CTLA4Ig-treated mice. We have demonstrated for the first time that the development of spontaneously occurring IgA nephropathy can be prevented in ddY mice by blocking the CD28-B7 interaction using a soluble form of CTLA4Ig. These results suggest that a costimulatory signal via CD28-B7 may play a crucial role in the development and progression of IgA nephropathy.

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: The performance characteristics of a microwave plasma source are presented. The plasma source consists of two chambers: chamber 1 generates a high-density plasma over which a magnetic field is applied at electron cyclotron resonance condition or greater, and chamber 2 makes the plasma uniform in its lower region by surrounding the peripheral region with magnetic multipole line-cusp fields. Plasma parameters were measured with a movable Langmuir probe located 1 cm above a plasma grid which is attached at the bottom of chamber 2. The dependence of plasma parameters on the magnetic field configuration, gas pressure and microwave power were examined, and radial distributions were measured. Uniform high-density plasmas over a 9-cm-diam area were produced on the plasma grid in a suitable magnetic field configuration, and uniformity was maintained over a wide pressure range. The uniform density region was determined by the magnetic multipole fields existing in chamber 2's peripheral region. The ion beam current density evaluated from the extracted ion beam correlated well with the ion saturation current density estimated from the plasma parameters.

Notes: Abstract Acute renal failure (ARF) occurred in a 47-year-old man with hemophagocytic syndrome. Histological findings of the kidney revealed diffuse infiltration of interstitium by phagocytosing cells mixed with atypical lymphoid cells of varying size. The cytological features of the lymphoid population in liver and spleen were consistent with a diagnosis of peripheral T-cell lymphoma. We believe that this ARF could have been exacerbated by the interstitial infiltration of phagocytosing cells, reactive lymphoid cells, and T-cell lymphoma cells.

Notes: Abstract Background. Vascular endothelial growth factor (VEGF) is a selective endothelial growth factor which potently enhances microvascular permeability. In the kidney, VEGF mRNA is known to be highly expressed in visceral epithelial cells in glomeruli. However, the physiological role of VEGF in glomerular function and its involvement in the pathogenesis of proteinuria are not clear. The present studies were designed to determine whether altered expression of VEGF mRNA was observed in the course of puromycin aminonucleoside (PAN) nephrosis in rats (a model of human minimal change nephrosis). Methods. The message level of VEGF in isolated glomeruli of PAN nephrosis rats was measured using a ribonuclease protection assay. Results. VEGF expression began to decrease 4 days after PAN injection and could not be detected in the nephrotic stage of PAN nephrosis (on days 8 and 16). In the remission of stage of PAN nephrosis (on day 28), mRNA was restored to the control level. Conclusions. According to our results, a functional defect in the VEGF expression of visceral epithelial cells was observed in PAN nephrosis. VEGF could be a functional marker of visceral epithelial cells, and the loss of normal expression of VEGF after damage to visceral epithelial cells could affect glomerular endothelial cell function in PAN nephrosis.