Low methane concentration in the breath of Japanese

A survey of breath methane excretion in Japanese is reported in this paper. The prevalence of methane excretion was 15% in 231 Japanese subjects, which was significantly lower than the range 33-60% reported in Canada and the USA. The prevalence of methane excretion was only 3% in males between the ages of 18-29 years old. However, it increased with age, and both males and females within the ages of 50-59 years old reached to almost the same value of 25-27%. When both parents were methane producers, 67% of their children were also methane producers. On the other hand, only 6% of the children were methane producers when both parents were methane non-producers. The prevalence of methane excretion was 55% in Caucasians who have lived in Japan for four years or longer. This is the same level reported in Canada and the USA. The effect of familial component and ethnic origin suggested that breath methane excretion is strongly affected by genetic factors.     

Association of solute carrier family 12 (sodium/chloride) member 3 with diabetic nephropathy, identified by genome-wide analyses of single nucleotide polymorphisms

To identify genetic elements that might confer susceptibility to diabetic nephropathy, we performed a genome-wide analysis of gene-based single nucleotide polymorphisms (SNPs) in a large cohort of Japanese patients with diabetes. In case-control association studies, patients with type 2 diabetes were divided into two groups, one having retinopathy as well as overt nephropathy and the other (the control group) having diabetic retinopathy but with no signs of renal involvement. Genotyping of these patients at >55,000 SNP loci indicated a gene encoding solute carrier family 12 member 3 (SLC12A3) to be a good candidate for the susceptibility to diabetic nephropathy, in view of a significant association of one landmark SNP located in the 24th intron (chi(2) = 15.4, P = 0.000087, odds ratio = 2.53 [95% CI 1.57-4.09]). Subsequent analysis of additional genetic variations in this gene identified several SNPs that were significantly associated with nephropathy, especially one in exon 23 (+78 G to A: Arg913Gln, chi(2) = 18.5, P = 0.00002, odds ratio = 2.53 [95% CI 1.64-3.90]). The results implicated that substitution of Arg913 to Gln in the SLC12A3 gene might reduce the risk to develop diabetic nephropathy and suggested that the gene product might be a potential target for the prevention or treatment of this disease.     

Brain fiber tracking with clinically feasible diffusion-tensor MR imaging: initial experience

Two technical challenges must be overcome before brain fiber tracking with diffusion-tensor magnetic resonance (MR) imaging can be applied to clinical practice: Imaging time must be shortened, and image distortion must be minimized. Single-shot echo-planar MR imaging with parallel imaging technique enabled both objectives to be accomplished. Twenty-three consecutive patients with brain tumors underwent MR imaging with a 1.5-T whole-body MR system. Fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. This diffusion-tensor MR imaging method with the parallel imaging technique allows clinically feasible brain fiber tracking.     

Comparison of Tc-99m-GSA scintigraphy with hepatic fibrosis and regeneration in patients with hepatectomy

OBJECTIVE: Liver regeneration after hepatectomy is correlated with liver fibrosis. Retrospectively, we compared three quantitative indices (HH15, LHL15 and LU15) of Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (Tc-99m-GSA) liver scintigraphy with liver fibrosis; in particular, we compared the HH15 index and the rate of remnant liver regeneration. METHODS: Fifty-three patients who had undergone hepatectomy were enrolled in this study. The non-neoplastic parts of their resected specimens were divided into 5 groups (F0-F4) according to the degree of liver fibrosis, as determined using the New Inuyama classification system: F0, no fibrosis (n = 12); F1, portal fibrosis widening (n = 12); F2, portal fibrosis widening with bridging fibrosis (n = 14); F3, bridging fibrosis plus lobular distortion (n = 7); F4, liver cirrhosis (n = 8). RESULTS: When the cases were divided into a no or mild fibrosis group (F0 and F1) and a moderate or severe fibrosis or cirrhosis group (F2, F3 and F4), all of the indices were significantly different between the two groups. In this analysis, the areas (Az) under the receiver operating characteristic (ROC) curves for the HH15 and LHL15 indices were very similar, while the Az for the LU15 index was smaller. An HH15 index equal to 0.52 was the most accurate, producing a 79.3% sensitivity and a 75.0% specificity rating. When 18 patients that had received a CT scan one month after hepatectomy were divided into 2 groups according to their HH15 value (group A, HH15 < or = 0.52; group B, HH15 > 0.52), group A exhibited a better regeneration rate. CONCLUSION: Tc-99m-GSA scintigraphy is well correlated with liver fibrosis and may be useful for non-invasive, preoperative evaluations of liver fibrosis. The HH15 index, in particular, may be useful for predicting the rate of liver regeneration after hepatectomy.     

Four-dimensional computed tomography (4D CT)--concepts and preliminary development

Four-dimensional computed tomography (4D CT) is a dynamic volume imaging system of moving organs with an image quality comparable to that of conventional CT. 4D CT will be realized by several technical breakthroughs for dynamic cone-beam CT: (1) a large-area two-dimensional (2D) detector; (2) high-speed data transfer system; (3) reconstruction algorithms; (4) ultra-high-speed reconstruction computer; and (5) high-speed, continuously rotating gantry. Among these, development of the 2D detector is one of the main tasks because it should have as wide a dynamic range and as high a data acquisition speed (view rate) as present CT detectors. We are now developing a 4D CT scanner together with the key components. It will take one volume image in 0.5 sec with a 3D matrix of 512 x 512 x 512. This paper describes the concepts and designs of the 4D CT system, as well as preliminary development of the 2D detector.     

A case of renal cell carcinoma metastasizing to contralateral perirenal fat

Extremely rarely renal cell carcinoma metastasizes to the contralateral perirenal fat. A 57-year-old male was admitted with macroscopic hematuria and lower left abdominal pain in December 1994. He was diagnosed with left renal cancer, and underwent left radical nephrectomy (RCC pT2, grade 1) in January 1995. Followup imaging studies showed a tumor arising from the right perirenal fat in 5 years. Tumor excision was performed in May 2000. Pathological findings revealed renal cell carcinoma growing in the fat, which had the same, pathology as the left renal cancer.     

Surgical treatment for esophageal cancer in elderly patients over 75 years of age

We performed 127 esophageal resections for the esophageal cancer patient from December 1995 to September 2001. It was separated to under 70 years old patients group (group I), 71-74 years old patients group (group II), and over 75 years old patients group (group III). RESULTS: Postoperative complication was occurred in 53 cases (41.7%) within all of 127 esophageal resected cases. It was 33.7% in group I, 53.6% in group II, 62.5% in group III. Four years survival rate of each group is 38.3% in group I, 44.6% in group II, 31.3% in group III. It is significantly better in group II rather than in group III. Operative death rate is 12.5% (2 cases) in group III, 7.1% (2 cases) in group II, 3.6% (3 cases) in group I, and it is gradually higher and higher by patient's age. CONCLUSIONS: (1) In the esophageal cancer patient over 75 years old, postoperative complication rate is higher than under 74 years old patients, and prognosis is significantly poor rather than in 70-74 years old patients group. (2) In the esophageal cancer patient over 75 years old, we considered it is good indication of esophagectomy for stage I and stage II patient without preoperative complication, however, there are no operative indication for stage III and stage IV patient.