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We investigate historical regional climate changes in Japan from 1959 to 2020, analyzing a high-resolution dynamical downscaling forced by the Japanese 55-year Reanalysis (JRA-55). One-year continuous simulations are conducted by the non-hydrostatic regional climate model with a land surface model that includes the snow accumulation process, which enables us to evaluate the seasonal variation of snow cover in all of Japan. Our simulation reproduces interannual variations of the annual mean surface air temperature and annual total precipitation, and it shows rapid warming since around 1980. The annual maximum snow depth and annual maximum daily snowfall show significant decreasing trends at lower elevations on the Japan Sea sides of eastern and western Japan. Areas at higher elevations in eastern Japan show no trend in the maximum snow depth and a significant increasing trend in the maximum daily snowfall. In northern Japan, altitudinal dependencies in snow depth and snowfall changes are smaller on the Japan Sea side than on the Pacific Ocean side: the Japan Sea side shows insignificant changes in snow depth at all elevations, while the Pacific Ocean side shows decreasing and significant increasing trends at lower and higher elevations, respectively. The total number of snow-covered days is decreasing at most elevations in all regions, while the rate of decrease is smaller at higher elevations and latitudes. Composite analyses of annual maximum daily snowfall events at one prefectural city facing the Japan Sea in central Japan indicate that heavy daily snowfall occurs when the Japan Polar air mass Convergence Zone appears over the Japan Sea and the snowfall amounts show increasing and decreasing trends over the mountainous and coastal areas, respectively, due to historical warming and moistening. Our results are basically consistent with previous studies that have focused on future changes in snow depth and snowfall.

Both monocyte-granulocytapheresis (M-GCAP) and leukocytapheresis (LCAP) are categorized as extracorporeal leukocyte removal therapies (ECCTs). These therapies have been recognized as efficient adjuncts for patients of steroid-resistant ulcerative colitis (UC). This study aimed to consider the adaptation and the limitation of these new therapies from the clinical standpoint based on a case of UC showing strong resistance to high-dose continuous steroid injection therapy. The patient successfully underwent a scheduled colectomy while maintaining remission after applying M-GCAP and LCAP independently. Surgical therapy was chosen because of a deep ulcer in the patient's sigmoid colon, which was assumed to constitute a future risk for perforation. This case suggests that combining ECCT with steroid therapy can maintain such poorly controlled and high-risk UC patients safely for the scheduled colectomy while improving the prognosis by reducing the dosage of steroid efficiently prior to operation.

The importance of tumor necrosis factor (TNF)-alpha and the TNF receptor gene polymorphisms in the etipathogenesis of inflammatory bowel disease (IBD) has not been elucidated. DNA from peripheral blood samples was obtained from 124 patients with Crohn's disease (CD), 106 patients with ulcerative colitis (UC), and 111 unrelated healthy controls. We examined two single nucleotide polymorphisms (SNPs) of the TNF-alpha gene, TNF (–308 G/A and –238 G/A), an SNP of the TNF receptor superfamily member 1A gene, TNFRSF1A(also known as TNFR1), at codon 12 in exon 1 (CCA/CCG), and two SNPs of the 1B gene, TNFRSF1B (also known as TNFR2), (1466 A/G and 1493 C/T). There was a difference in the carrier frequency for haplotype AG (–308 A, –238 G) between UC patients and the controls (OR=4.76, 95% CI=1.53–14.74, P

As we consider succinic acid to be an exacerbating factor in ulcerative colitis, we investigated its influence on rat colonic mucosa in terms of mucosal blood flow and superoxide generation. We measured mucosal blood flow by the hydrogen gas clearance method and superoxide generation by the chemiluminescence method, and observed histopathological findings to determine the effects of succinic acid. After the instillation of succinic acid of any concentration tested to the colon, mucosal blood flow decreased. Histopathologically, the higher the concentration of succinic acid, the greater was the erosion formation in the colonic mucosa, while significant polymorpho-nuclear cell infiltration and superoxide generation from colon tissue were observed with 0.01% succinic acid compared with higher or lower concentrations. Succinic acid, at fecal concentrations found in active stage ulcerative colitis, appears to be implicated in mucosal injury, mediated by a decrease in colonic mucosal blood flow and infiltration of superoxide-generating polymorpho-nuclear cells into the mucosa.