Suppression of genotoxicity of carcinogens by (-)-epigallocatechin gallate.

Epidemiological evidence shows that green tea may be a factor in lowering cancer risk. We have investigated the possibility that (-)-epigallocatechin gallate (EGCG), a major polyphenol in green tea, might be an antimutagenic substance. In the Ames Salmonella test, EGCG suppressed the direct-acting mutagenicity of 3-hydroxyamino-1-methyl-5H-pyrido-[4,3-b]indole (Trp-P-2(NHOH)) and 2-hydroxyamino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1(NHOH)), the activated forms of food-derived carcinogens 3-amino-1-methyl-5H-pyrido[4,3-b]indole and 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole. EGCG was also effective in reducing the mutagenicity of Trp-P-2(NHOH) in mouse FM3A cells in culture. Furthermore, EGCG demonstrated a suppressive effect in the in vivo Drosophila mutation assays, i.e., the wing spot test, and the DNA repair test, on several carcinogens. EGCG was also effective in inhibiting DNA single-strand breaks in vitro caused by Glu-P-1(NHOH). We conclude that the mechanism of inhibition may not have resulted from direct interaction between EGCG and the mutagens, but rather from indirect interception of mutagen action by EGCG.     

Comparison of the effects of isoflurane and sevoflurane on protein tyrosine phosphorylation-mediated vascular contraction

BACKGROUND: Isoflurane induces greater effects on vasodilation and decreasing blood pressure than sevoflurane. Tyrosine kinase-catalyzed protein tyrosine phosphorylation plays an important role in regulating vascular smooth muscle contraction. The aim of the present study was to compare the effects of isoflurane and sevoflurane on tyrosine phosphorylation-mediated vascular constriction, by assessing the degree of sodium orthovanadate (Na(3)VO(4), tyrosine phosphatase inhibitor)-induced contraction and protein tyrosine phosphorylation of rat aortic smooth muscle. METHODS: Na(3)VO(4)-induced contraction and protein tyrosine phosphorylation of rat aortic smooth muscle were measured in the presence of genistein, a tyrosine kinase inhibitor, and different concentrations of isoflurane and sevoflurane, using isometric force measurement and Western blot, respectively. RESULTS: Na(3)VO(4) (10(-4) M) induced sustained contraction and tyrosine phosphorylation of substrates that were both markedly attenuated in the presence of genistein (5 x 10(-5) M). Isoflurane and sevoflurane dose-dependently (1, 2, 3 MAC) attenuated the Na(3)VO(4)-induced contraction (P < 0.05-0.005, n = 8), with a greater degree of inhibition by isoflurane than sevoflurane at 2 MAC (P < 0.01) and 3 MAC (P < 0.05). Both anesthetics also attenuated the total band density of the Na(3)VO(4)-induced, tyrosine-phosphorylated substrates in a concentration-dependent manner (P < 0.05-0.005, n = 4), with much greater attenuation by isoflurane than sevoflurane at 1 and 2 MAC (P < 0.05), respectively. CONCLUSION: The results of the present study demonstrate that isoflurane exhibits a greater degree of inhibition on the Na(3)VO(4)-stimulated contraction and protein tyrosine phosphorylation of rat aortic smooth muscle compared with sevoflurane. These findings suggest that isoflurane depresses the protein tyrosine phosphorylation-mediated contraction of vascular smooth muscle to a greater degree than sevoflurane.     

Use of a Home Water Filter in the Reduction of Trihalomethanes and Total Organic Halogen in Tap Water: Forty-One Samples from Osaka City and Surrounding Cities of Japan in 1999, 2000, and 2004

No abstract available.     

Apatite-wollastonite containing glass ceramic-fibrin mixture as a bone defect filler

The purpose of this study was to evaluate the usefulness of a mixture of apatite-wollastonite containing glass ceramic (A-W.GC, 42-60 mesh in granule size) with fibrin as a bone defect filler. A bone defect was drilled in the proximal metaphysis of the rat tibia and was filled with (1) fibrin glue, (2) A-W.GC granules, or (3) A-W.GC-fibrin mixture. Nothing was placed in the defect of the controls. The animals were serially sacrificed until 8 weeks after the operation, and the defect site was histologically examined and histomorphometrically analyzed for quantitative evaluation of newly formed bone and blood vessels. The use of fibrin glue as the binder markedly increased the ease of handling the A-W.GC granules. In the controls, little trabecular regeneration was observed in the defect site. Early vascularization (confirmed by microangiography) increased and the repairing process was accelerated in the defects filled with fibrin. In these defects filled with A-W.GC granules, good bone formation was observed around the granules. Bone formation was accelerated in the defects filled with A-W.GC fibrin mixture. Thus, the mixture showed good osteoconductive potential as well as acceleration of the repair process. Therefore, A-W.GC-fibrin mixture is considered to be a useful bone defect filler.     

Coding strategy of rice stripe virus: major nonstructural protein is encoded in viral RNA segment 4 and coat protein in RNA complementary to segment 3

The two major proteins found in plants infected with rice stripe virus (RSV), coat protein and a major nonstructural protein (major NS), were purified and their partial amino acid sequences were determined. Oligonucleotides were synthesized according to the amino acid sequence information, and used as probes for Northern blot analyses of four single-stranded RNA species (segments 1-4) and four double-stranded RNA species of RSV. The results indicated that the coding strategy of RSV was similar to those of ambisense viruses: Segment 3 coded for the coat protein in the (-) sense while segment 4 coded for the major NS protein in the (+) sense.     

Impact of Inadequate Calorie Intake on Mortality and Hospitalization in Stable Patients with Chronic Heart Failure

Malnutrition is highly prevalent in patients with heart failure (HF), but the precise impact of dietary energy deficiency on HF patients’ clinical outcomes is not known. We investigated the associations between inadequate calorie intake and adverse clinical events in 145 stable outpatients with chronic HF who had a history of hospitalization due to worsening HF. To assess the patients’ dietary pattern, we used a brief self-administered diet-history questionnaire (BDHQ). Inadequate calorie intake was defined as <60% of the estimated energy requirement. In the total chronic HF cohort, the median calorie intake was 1628 kcal/day. Forty-four patients (30%) were identified as having an inadequate calorie intake. A Kaplan–Meier analysis revealed that the patients with inadequate calorie intake had significantly worse clinical outcomes including all-cause death and HF-related hospitalization during the 1-year follow-up period versus those with adequate calorie intake (20% vs. 5%, p < 0.01). A multivariate logistic regression analysis showed that inadequate calorie intake was an independent predictor of adverse clinical events after adjustment for various factors that may influence patients’ calorie intake. Among patients with chronic HF, inadequate calorie intake was associated with an increased risk of all-cause mortality and rehospitalization due to worsening HF. However, our results are preliminary and larger studies with direct measurements of dietary calorie intake and total energy expenditure are needed to clarify the intrinsic nature of this relationship.     

JTT-130, a novel intestine-specific inhibitor of microsomal triglyceride transfer protein, suppresses high fat diet-induced obesity and glucose intolerance in Sprague-Dawley rats

Aim: Microsomal triglyceride transfer protein (MTP) takes part in the mobilization and secretion of triglyceride‐rich lipoproteins from enterocytes and hepatocytes. We investigated the effects of JTT‐130, a novel intestine‐specific MTP inhibitor, on high fat diet‐induced obesity and glucose intolerance. Methods: Male Sprague‐Dawley rats were fed a 3.1% fat diet or a 35% fat diet with or without JTT‐130 as a food admixture (0.029%). Food intake, body weight, abdominal fat, hepatic triglyceride, faecal free fatty acids and plasma levels of glucagon‐like peptide‐1 (GLP‐1) and peptide YY (PYY) were assessed. Plasma levels of glucose and insulin were measured during intraperitoneal glucose tolerance tests. In addition, indirect calorimetry was performed on rats fed with a 35% fat diet. Results: JTT‐130 treatment decreased body weights, abdominal fat and hepatic triglyceride with suppression of food intake and elevation of faecal free fatty acids and plasma GLP‐1 and PYY levels in rats fed with the 35% fat diet, whereas no significant effects on these parameters except for increased faecal free fatty acids were observed in rats fed with the 3.1% fat diet. JTT‐130 treatment decreased plasma levels of glucose and insulin during intraperitoneal glucose tolerance tests on rats fed with the 35% fat diet, but not on rats fed with the 3.1% fat diet. JTT‐130‐treated rats showed increased O₂ consumption and CO₂ production on a 35% fat diet. Conclusions: JTT‐130 suppresses high fat diet‐induced obesity and glucose intolerance with suppression of food intake and fat absorption and could be useful for prevention and treatment of obesity and obesity‐related insulin resistance.     

Color Doppler endoscopic ultrasonography in identifying groups at a high-risk of recurrence of esophageal varices after endoscopic treatment

BACKGROUND: Our preliminary study indicated that either a high hepatofugal flow velocity in the left gastric vein (LGV) or an anterior branch dominant pattern seen under color Doppler EUS (CD-EUS) were possible contributing risk factors for variceal recurrence after endoscopic treatment. However, the sample size was too small, and in this study we aimed to validate the results of the preliminary study. METHODS: Sixty-eight patients treated for moderate or large esophageal varices between 2001 and 2004 at a single university hospital were enrolled in this study. CD-EUS was followed by endoscopic variceal ligation and sclerotherapy. RESULTS: Patients were classified into either a high-risk group, which exhibited anterior branch dominance and flow velocity of 12 cm/s or more, or a low-risk group, which included all other patients. Half of the patients in the high-risk group exhibited a recurrence within half a year, whereas it took almost 2 years for half of the patients in the other group to exhibit a recurrence (P=0.0044). Using the Cox proportional hazard model with multivariate analysis, only the features of the high-risk group were significant in triggering recurrence of varices (hazard ratio [HR], 3.00; 95% confidence interval [CI], 1.35-6.65; P<0.001). CONCLUSIONS: These results suggest that patients showing anterior branch dominance and rapid hepatofugal flow velocity in the LGV on CD-EUS examination may have a high risk of an early recurrence of esophageal varices.