PLC Rice Series: Low-Protein Rice Products.

Dietary therapy through a low-protein diet (LPD) has long been used for preserving the renal function of patients with chronic kidney disease (CKD). Reducing the amount of protein ingested from rice would make it possible to allocate the difference to side dishes, thereby improving the quality of meals and facilitating adherence to LPD. If it is possible to remove protein from rice, it would minimize the need to cut down on main dishes and make it easier for patients to follow the LPD. We developed exclusive technology for digesting and removing protein from rice grain using microorganism-derived enzyme product, and technology for processing the Low-Protein Rice (LPR) thus obtained into a palatable food product. By combining these technologies, we can reliably manufacture delicious, high quality, low protein rice product, which can be eaten repeatedly as staple. Our LPR products, "PLC Rice" series are helpful to enhance the quality of mealtimes for CKD patients by increasing their range of food choices. It is therefore reasonable to say that PLC Rice products offer high added value, as it not only facilitates adhesion to LPD but also add satisfaction and contentment to daily meals, helping to enhance the quality of life of patients with CKD.

Antimicrobial activity and mechanism of action of a novel cationic α-helical dodecapeptide, a partial sequence of cyanate lyase from rice.

CL(14-25), a dodecapeptide, that is a partial region near N-terminus of cyanate lyase (CL, EC 4.3.99.1) from rice (Oryza sativa L. japonica), contains three arginine and two lysine residues. It was a novel cationic α-helical antimicrobial peptide. The antimicrobial activity of CL(14-25) against Porphyromonas gingivalis, a periodontal pathogen, was quantitatively evaluated by a chemiluminescence method that measures ATP derived from viable cells. The 50% growth-inhibitory concentration of CL(14-25) against P. gingivalis cells was 145 µM. CL(14-25), even at a concentration of 800 µM, had no hemolytic activity. When giant unilamellar vesicles (GUVs) that mimic the membrane composition of Gram-negative bacteria were used, microscopy image analysis suggested that CL(14-25) disrupted GUVs in a detergent-like manner. Therefore, CL(14-25) appears to exhibit antimicrobial activity through membrane disruption. To investigate the contribution of cationic amino acid residues in CL(14-25) to its antimicrobial activity, we synthesized four truncated CL analogs, in which one or two cationic amino acid residues were deleted from the N- and C- termini of CL(14-25). The degrees of calcein leakage from large unilamellar vesicles (LUVs) and 3,3'-dipropylthiadicarbocyanine iodide (diSC3-5) release from P. gingivalis cells induced by truncated CL analogs were closely related to their antimicrobial activities. CL analogs, which were truncated by removing an arginine residue from the N-terminus and a lysine residue from the C-terminus maintained their antimicrobial activity. However, CL analogs, which were further truncated by removing two arginine residues from the N-terminus, and an arginine and a lysine residue from the C-terminus, rarely exhibited antimicrobial activity.

[Genetic basis for dementia].

A goal of genetic research is to identify risk factor loci for complex disorders, and to understand a molecular mechanism of the factor on development of the disease. Dementia is the most common neurodegererative disorder in the elderly. Three frequent neurodegererative dementias are Alzheimer disease, dementia with Lewy bodies, and frontotemporal lobar degeneration, characterized by senile plaque with amyloid beta and neurofibrillary tangles with tau, Lewy body with alpha-synuclein, tau or tau-negative ubiquitin-immunoreactive neuronal inclusions with TDP-43, respectively. Overlapping symptoms, progress and neuropathological findings often complicate the diagnosis. Genetic risk factors obtained by genome-wide association study might provide new insight into etiology common to dementia.

Genetic association study on in and around the APOE in late-onset Alzheimer disease in Japanese.

The epsilon4 allele of APOE is a well-characterized genetic risk factor for late-onset Alzheimer disease (LOAD). Nevertheless, using high-density single nucleotide polymorphisms (SNPs), there have only been a few studies involving genetic association and linkage disequilibrium (LD) analyses of in and around the APOE. Here, we report fine mapping of a genomic region (about 200 kb) including the APOE in Japanese using 260 SNPs (mean intermaker distance, 0.77 kb). A case-control study demonstrated that 36 of these SNPs exhibited significance after adjustment for multiple testing. These SNPs are located in a genomic region including four genes, PVRL2, TOMM40, APOE and APOC1. Recombination rate estimation revealed that the associated region is firmly sandwiched between two recombination hotspots. Strong LD between these SNPs was observed (mean |D'|=0.914). These data suggest that the three genes other than APOE, i.e. PVRL2, TOMM40 and APOC1, could also yield a predisposition to LOAD.