Heat/moisture‐treated potato and corn starch granules were observed by microscopy and X‐ray diffraction patterns were obtained. A scanning electron microscope (SEM) photograph of the cross section of the heat/moisture‐treated potato and corn starch granules showed a large hollow area about 1/3 of the diameter at the center of the starch granules and a layered structure resembling growth rings. From the X‐ray diagrams it was confirmed that heat/moisture‐treatment caused an alteration from the B‐type in the direction an A‐type structure in potato, whereas corn starch did not change and maintained an A‐type structure. The enzymatic digestibility of heat/moisture‐treated starch was found to be less resistant than that of native starch.

Renal biopsy specimens from patients with membranous nephropathy (MN) were studied using immunohistochemical labelling to clarify the aetiological significance of Helicobacter pylori antigen in this disease. Sixteen specimens were examined, from 7 male and 9 female MN patients. Renal specimens from patients with diabetic nephropathy and IgA nephropathy, and from autopsied patients without renal diseases were obtained as controls. Immunohistochemical labelling was performed using one polyclonal antibody and three monoclonal antibodies against H. pylori. Specimens from 11 of the MN patients revealed granular deposits along the glomerular capillary walls, which reacted positively with polyclonal antibody after trypsin pretreatment. None of the control specimens revealed positive labelling. The MN specimens showed no positive reaction with the primary antibody, which had been treated for immunoabsorption testing using sonicated H. pylori. We also determined H. pylori status in these MN patients histologically and/or serologically. Of the 11 patients whose glomeruli were positive for anti-H. pylori antibody, 7 were suitable for analysis, and all were regarded as positive for H. pylori infection. These results suggest that the presence of a specific antigen in the glomeruli of patients with MN and H. pylori infection may be involved in the pathogenesis of MN.

Lipoprotein glomerulopathy is a disease characterized by intraglomerular lipoprotein thrombi and abnormal lipid metabolism similar to type III hyperlipoproteinemia. Recently, glomerular lesions compatible with lipoprotein glomerulopathy were found in a 38-year-old man. In this case, plasma apolipoprotein (apo) E level was elevated, and the apo E isoform was heterozygous E2/3, similar to most of the reported cases of lipoprotein glomerulopathy. However, the plasma levels of triglyceride and total cholesterol were within their respective normal ranges. Review in 11 cases revealed that lipoprotein glomerulopathy was not always associated with hyperlipidemia, and that apo E abnormality was always recognized. These findings suggest that lipoprotein thrombi associated with lipoprotein glomerulopathy are not induced via systemic hyperlipidemia but may be formed by intraglomerular accumulation of lipoprotein composed of abnormal apo E.

Calpain represents a family of Ca2+-dependent cytosolic cysteine proteases found in almost all eukaryotes and some bacteria, and is involved in a variety of biological phenomena, including brain function. Several substrates of calpain are aggressively proteolyzed under pathological conditions, e.g., in neurodegenerating processes, fodrin is proteolyzed by calpain. Because very small amounts of substrate are proteolyzed by calpain under normal biological conditions, the molecular identities of calpain substrates are largely unknown. In this study, an extensive survey of the substrates of p94/calpain 3 in COS7 cells was executed using iTRAQ™ labeling and 2-D LC-MALDI analysis. p94 was used because: (i) several p94 splicing variants are expressed in brain tissue even though p94 itself is a skeletal-muscle-specific calpain, and (ii) it exhibits Ca2+-independent activity in COS cells, which makes it useful for evaluating the effects of p94 protease activity on proteins without perturbing the cells. Our approach revealed several novel protein substrates for p94, including the substrates of conventional calpains, components of the protein synthesis system, and enzymes of the glycolytic pathway. The results demonstrate the usefulness and sensitivity of this approach for mining calpain substrates. A combination of this method with other analytical methods would contribute to elucidation of the biological relevance of the calpain family.

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