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H Tanaka

Publications and source records attributed to H Tanaka.

At least 73 records · Page 4Linked to original sources

Evaluation of intraoperative infusion solution using a complete anhepatic model in baby pigs.

Compared to cadaveric liver transplantation, living-related liver transplantation (LRLT) has the physiological advantage of avoiding hemodynamic changes due to the nonsystemic clamping of the inferior vena cava (IVC). However, metabolic changes in the level of blood glucose and lactate usually occur during the anhepatic phase in LRLT. For pediatric patients, intraoperative infusions have the potential to maintain immature homeostasis during LRLT. In the present study, a complete anhepatic model of baby pigs with nonsystemic clamping of IVC, which mimics the procedure of pediatric LRLT, was established using a heparin-coated tube as an internal shunt lactate Ringer solution (LR, Lactec), acetate Ringer solution (AR, VeenF), and a solution comprising acetate Ringer with 1% glucose (AR-G, Phisio140) were tested using piglets. Hemodynamic and metabolic (blood gas analysis, electrolytes, blood lactate, and glucose) changes were observed during the anhepatic phase. Although no major difference was observed in hemodynamic parameters, arterial blood gas data, or concentration of electrolytes among the three solution groups, significant progressive hyperlactatemia was observed in the LR group. Also, though severe hypoglycemia was found in the LR and AR groups, the AR-G group maintained blood glucose levels throughout the anhepatic phase. To conclude, using the simplified pig anhepatic model, we evaluated various solutions for pediatric LRLT.

Animals↗

Long-period accelerometer monitoring shows the role of physical activity in overweight and obesity.

CONTEXT: Physical activity (PA) plays an important role in obesity. A new accelerometer has been developed to assess total energy expenditure as well as PA. OBJECTIVE: To investigate the association of PA with overweight and obesity in Japanese men and women, a large cross-sectional study was performed using a single-axis accelerometer. DESIGN, SETTING AND PARTICIPANTS: Population-based cross-sectional study of Japanese 18-84 y of age. Height, body weight and PA were measured in 400 male and 388 female Japanese volunteers from 1999 to 2000. The outcome measurements were overweight and obesity, which are defined as a body mass index >/=25 kg/m(2). PA was measured for 1 to 4 weeks and was then categorized into three activity levels, which were defined as light, moderate and vigorous PA. RESULTS: Prevalence of overweight and obesity was 22.3%. Number of steps and time spent in moderate and vigorous PA per day were lower in overweight and obese individuals. No difference was found in time spent in light PA. Individuals who are in the 4th and 5th quintile of moderate and vigorous PA showed a significantly lower body mass index. When odd ratios (ORs) of overweight and obesity estimated by logistic regression were used as effect measures, overweight and obesity were negatively associated with vigorous PA (ORs=0.91). CONCLUSION: These results indicate that overweight and obese individuals have a lower step rate and are spending less time for moderate to vigorous PA. Participation in vigorous PA is an important predictor of overweight and obesity.

Adolescent↗

Brachial-ankle pulse wave velocity: an index of central arterial stiffness?

Brachial-ankle pulse wave velocity (baPWV) is a promising technique to assess arterial stiffness conveniently. However, it is not known whether baPWV is associated with well-established indices of central arterial stiffness. We determined the relation of baPWV with aortic (carotid-femoral) PWV, leg (femoral-ankle) PWV, and carotid augmentation index (AI) by using both cross-sectional and interventional approaches. First, we studied 409 healthy adults aged 18-76 years. baPWV correlated significantly with aortic PWV (r = 0.76), leg PWV (r = 0.76), and carotid AI (r = 0.52). A stepwise regression analysis revealed that aortic PWV was the primary independent correlate of baPWV, explaining 58% of the total variance in baPWV. Additional 23% of the variance was explained by leg PWV. Second, 13 sedentary healthy men were studied before and after a 16-week moderate aerobic exercise intervention (brisk walking to jogging; 30-45 min/day; 4-5 days/week). Reductions in aortic PWV observed with the exercise intervention were significantly and positively associated with the corresponding changes in baPWV (r = 0.74). A stepwise regression analysis revealed that changes in aortic PWV were the only independent correlate of changes in baPWV (beta = 0.74), explaining 55% of the total variance. These results suggest that baPWV may provide qualitatively similar information to those derived from central arterial stiffness although some portions of baPWV may be determined by peripheral arterial stiffness.

Adolescent↗

Gene expression profiling of exercise-induced cardiac hypertrophy in rats.

AIMS: Exercise training causes physiological cardiac hypertrophy, which acts to enhance cardiac function during exercise. However, the underlying molecular mechanisms are unclear. We investigated gene expression profile of exercise training-induced cardiac hypertrophy using left ventricle (LV) excised from exercise-trained and sedentary control rats (12-week old). METHOD: Rats in the training group exercised on a treadmill for 8-week. RESULTS: Left ventricular mass index and wall thickness in the exercise-trained group were significantly greater than that in the control group, indicating that the trained rats developed cardiac hypertrophy. Of the 3800 genes analysed in the microarray analyses, a total of 75 relevant genes (upregulation of 33 genes and downregulation of 42 genes) displayed alterations with exercise training. Among these genes, we focused on glycogen synthase kinase (GSK)-3beta, calcineurin-inhibitor (Cain), and endothelin (ET)-1 for their implicated roles in pathological cardiac hypertrophy, and confirmed the results of microarray analysis at mRNA and protein/peptide levels using quantitative PCR, Western blot, and EIA analyses. The gene expression of GSK-3beta decreased significantly and those of Cain and ET-1 increased significantly with exercise training. Furthermore, LV mass index was significantly correlated with GSK-3beta protein activity (r = -0.70, P < 0.01) and tissue ET-1 concentration (r = 0.52, P < 0.05). There were no changes in gene expressions in brain natriuretic peptide (BNP), angiotensin-correcting enzyme (ACE), interleukin-6, and vascular cell adhesion molecule (VCAM)-1. CONCLUSION: These findings suggest that physiological and pathological LV hypertrophy may share some of the same molecular mechanisms in inducing LV hypertrophy (e.g. GSK-3beta, Cain, and ET-1) and that other genes (e.g. BNP, ACE) may differentiate physiological from pathological LV hypertrophy.

Adaptation, Physiological↗

Sox2 expression in human stomach adenocarcinomas with gastric and gastric-and-intestinal-mixed phenotypes.

AIMS: Other than ectopic expression of intestinal transcription factors, Cdx1 and Cdx2, the molecular mechanisms underlying gastric and intestinal phenotypes of human stomach adenocarcinomas have yet to be clarified in detail. We have reported that Sox2, an HMG-box gastric transcription factor, is expressed in normal gastric mucosa and down-regulated in intestinal metaplasia. METHODS AND RESULTS: We analysed mRNA levels of Sox2 and other differentiation markers in 50 surgically resected stomach adenocarcinomas, immunohistochemically classified into gastric (G), gastric-and-intestinal (GI)-mixed, solely intestinal (I), and null (N) types. Sox2 was found to be transcribed in G and GI-mixed type adenocarcinomas in accordance with MUC5AC and MUC6 expression, while Cdx1 and Cdx2 were up-regulated in GI-mixed and I types along with the expression of MUC2 and villin. In the N type, both gastric and intestinal transcription factors were suppressed. Immunohistochemistry confirmed expression of Sox2 in MUC5AC+ lesions and Cdx2 localization together with MUC2. A stomach adenocarcinoma cell line, KATOIII, demonstrated both MUC5AC and Sox2, although MUC5AC mRNA was not detected in the Sox2+ AGS cell line. CONCLUSIONS: Sox2 may play an important role in maintaining a gastric phenotype in stomach cancers as well as in normal tissue, in cooperation with other cofactor(s).

Adenocarcinoma↗

HLA class II DPB1, DQA1, DQB1, and DRB1 genotypic associations with occupational allergic cough to Bunashimeji mushroom.

We previously reported that two-third of workers in a Bunashimeji mushroom (Hypsizigus marmoreus) farm complained of respiratory allergic symptoms, but one-third workers did not suffer from such symptoms even when working for a long period. CD4+ T-helper (Th) cells increased, and Th2/Th1 ratio increased in the allergic workers. To address these immunological backgrounds, we have investigated whether there is any relationship between mushroom allergy and human leukocyte antigen (HLA) class II alleles of DPB1, DQA1, DQB1, and DRB1 by using the polymerase chain reaction-restriction fragment length polymorphism (RFLP) and sequencing-based typing methods. We observed that the allele frequencies of DQA1*0103, DQB1*0601, and DRB1*0803 were significantly higher in the workers having no allergic symptoms than allergic workers (DQA1*0103: 57 vs 25%, DQB1*0601: 49 vs 14%, and DRB1*0803: 29 vs 0%). However, this phenomenon was not seen in workers producing another kind of mushroom, Honshimeji (Lyophyllum aggregatum). The HLA-DRB1*0803 allele alone, the DRB1*0803, DQA1*0103, DQB1*0601 haplotype, or both were negatively associated with allergy to Bunashimeji, and these alleles might be involved in the prevention of Bunashimeji mushroom-specific respiratory allergy.

Adult↗

Detection of periodontopathic bacteria and an oxidative stress marker in saliva from periodontitis patients.

We assessed the salivary levels of periodontopathic bacteria and 8-hydroxydeoxyguanosine (8-OHdG) in patients with periodontitis. The salivary levels of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia (formerly Bacteroides forsythus) were assessed using real-time polymerase chain reaction. The 8-OHdG levels were determined using an enzyme-linked immunosorbent assay. The salivary levels of 8-OHdG, P. gingivalis, and T. forsythia in the periodontitis patients were significantly higher than those in healthy subjects. By contrast, the A. actinomycetemcomitans level in healthy subjects was higher than that in periodontitis patients. 8-OHdG was significantly correlated with P. gingivalis. Statistically significant decreases in the levels of P. gingivalis, probing depth, bleeding on probing, and 8-OHdG were observed after initial periodontal treatment. These results suggest that the 8-OHdG levels in saliva reflect the load of periodontal pathogens. 8-OHdG could be a useful biomarker for assessing periodontal status accurately, and for evaluating the efficacy of periodontal treatment.

8-Hydroxy-2'-Deoxyguanosine↗

Floral variant of follicular lymphoma containing marginal zone B-cell component. Report of two cases.

We here report two unusual cases of floral variant of follicular lymphoma containing marginal zone B-cells. Histologically, the neoplastic follicles consisted of three distinct layers. The inner layer was composed of neoplastic germinal centers exhibiting a floral design and the middle layer had unusually prominent mantle zones. The outer zone of neoplastic follicles was surrounded by a pale cuff of marginal zone B-cells. Immunohistological study demonstrated that both the germinal center and marginal zone component lay within the follicular dendritic cell network. The germinal center component was CD10+ and bcl-2+. However, a portion of the marginal zone component weakly expressed bcl-2 but not CD10. Nodal marginal zone B-cell lymphoma (NMZBL) occasionally possesses "floral" lymphoid follicles. Follicular lymphoma with marginal zone differentiation is a high-risk variant of follicular lymphoma. In diagnostic practice, the differential diagnosis between the floral variant of follicular lymphoma containing marginal zone B-cells and the "floral variant" of NMZBL is important.

Adult↗

Implication of the peak serum level of mizoribine for control of the serum anti-dsDNA antibody titer in patients with lupus nephritis.

AIM: Mizoribine (MZR) is a novel selective inhibitor of inosine monophosphatase dehydrogenase that was developed in Japan. We previously reported the efficacy and safety of oral MZR pulse therapy, which is associated with elevated peak serum MZR levels, in selected patients with lupus nephritis. However, only limited information is available as yet on the optimal peak serum level of MZR that would yield an enhanced clinical efficacy without serious toxicity in patients with lupus nephritis. METHODS: A total of 11 patients with clinically stable lupus nephritis treated with oral MZR pulse therapy combined with low-dose prednisolone were enrolled in the cross-sectional study. The peak serum concentrations of MZR (as determined by HPLC) and the serum anti-dsDNA antibody titers (as determined by ELISA) were examined in the patients in order to evaluate the correlation between these two parameters. The correlation between the dose of MZR (mg/kg) administered orally as a single daily dose and the peak serum level of the drug was also examined. In two of the patients, serial measurements of the changes in the peak serum levels of MZR and anti-dsDNA titers could be conducted over 10 months. RESULTS: A significant inverse correlation (r = -0.596, p = 0.0116) was observed between the peak serum levels of MZR and the serum anti-dsDNA antibody titers in the study participants, while the dose of prednisolone remained unchanged. The peak level of MZR in the serum was significantly correlated with the single dose of MZR (r = 0.509, p = 0.0371). In the two patients in whom serial measurements were conducted, the first patient who showed a peak serum MZR level of less than 2.5-3.0 microg/ml eventually developed an increase of the serum anti-dsDNA titer with hypocomplementemia and proteinuria. On the other hand, in the second patient who showed a peak serum MZR level in excess of 4.0 microg/ml, persistently low serum anti-dsDNA titers with normocomplementemia were observed. CONCLUSION: Although this study is only a preliminary study conducted on a small sample, we speculate from the results that a peak serum level of MZR of at least more than 2.5-3.0 mirog/ml is necessary to achieve satisfactory clinical efficacy of the drug for the treatment of lupus nephritis. Further study is needed to confirm these preliminary findings.

Administration, Oral↗

C1-C2 point monitoring of low-dose cyclosporin a given as a single daily dose in children with steroid-dependent relapsing nephrotic syndrome.

AIM: It has been reported that the pharmacokinetics of cyclosporin A (CsA) in children is different from that in adults. It appears that, in general, pediatric patients metabolize CsA more rapidly than adult patients, necessitating the use of higher dose of the drug in pediatric transplant recipients. In this context, we speculated that single-dose daily administration of low-dose CsA may be associated with a higher peak blood level without associated trough blood level elevation, and thereby yield better results and allow safer use of the drug than the conventional twice daily administration dosing used for the treatment of childhood idiopathic nephrotic syndrome (INS). METHODS: A total of 10 children with steroid-dependent relapsing INS (9 with biopsy-proven minimal-change disease) who showed steroid toxicity were enrolled in the study. The initial daily dose of CsA (Neoral) used was around 2.0 mg/kg, given as a single daily dose before breakfast. The dose was subsequently adjusted to achieve a C1-C2 point blood level between 600 - 800 ng/ml. The dose of the concomitantly administered prednisolone was tapered following the commencement of CsA. RESULTS: The mean daily CsA dosage, the mean C1-C2 point blood level and the mean trough blood level in the subjects were 2.2 +/- 0.8 mg/kg, 754.0 +/- 71.9 ng/ml and 42.7 +/- 29.2 ng/ml, respectively. At the latest observation, after a mean duration of 17 months (6 - 24 months) of CsA therapy, the minimum dose of prednisolone required for maintenance of clinical remission and the calculated relapse rate were significantly decreased as compared to the respective pretreatment values (0.52 +/- 0.46 mg/kg on alternate days, vs. 0.97 +/- 0.63 mg/kg on alternate days, and 0.28 +/- 0.32 times per six months, vs. 1.06 +/- 0.41 times per six months, respectively, p = 0.005). No significant change was observed in the mean estimated GFR value as compared to the pretreatment value (183.1 +/- 35.4 ml/min/1.73 m2vs. 185.4 +/- 39.3 ml/min/1.73 m2). No evidence of CsA nephrotoxicity was observed in a repeat renal biopsy performed around 12 months after the commencement of CsA therapy in two patients. CONCLUSIONS: Despite the limitations of the study, our results suggest that administration of low-dose CsA as a single daily dose with C1-C2 point blood level monitoring might be an equally effective and safe and, therefore, more cost-beneficial, protocol for the treatment of steroid-dependent cases of relapsing INS, as conventional twice-daily administration of CsA with trough blood level monitoring. Further studies to confirm the long-term efficacy and safety of this CsA treatment protocol in larger numbers of patients are, however, needed.

Adolescent↗

[Pulmonary thromboembolism after thoracoscopic pulmonary wedge resection; report of a case].

We encountered a case of acute pulmonary embolism after lung cancer surgery. The case was a 64-year-old female. She was admitted to our hospital with an abnormal shadow on chest X-ray. There was a past history of hypopituitarism medicated with steroids. Chest computed tomography (CT) demonstrated ground glass attenuation shadow measuring 10 mm in the left upper lobe. She underwent left thoracoscopic pulmonary wedge resection due to bronchioloalveolar cell carcinoma. Postoperatively, the patient suddenly complained of chest pain and dyspnea the day after surgery. Chest CT showed left and right pulmonary arterial thromboembolism. Thrombolytic and anticoagulation therapy with urokinase and heparin sodium were immediately started. Venography demonstrated thrombus located in the vein of the bilateral lower leg region. We inserted an inferior vena cava filter to prevent aggravation of pulmonary embolism. After 11 days, CT showed completed thrombolysis in the bilateral pulmonary artery. The patient was discharged on the 25th postoperative day, and has been followed with anticoagulation therapy.

Acute Disease↗

[Left-sided adult Bochdalek hernia with right lung cancer; report of a case].

Bochdalek hernia is a common congenital anomaly in neonatal patients with risky respiratory distress and high mortarity, but can be seen in adults. A case of left-sided adult Bochdalek hernia with right lung cancer is reported. A 71-year-old female had been performed radition therapy for lung cancer in the right lower lobe. She was admitted to our hospital due to advanced lung cancer and pneumonia. On the 7th day after admission, she felt dyspnea and abdominal distention due to herniation of the stomach through the posterolateral defect of the diaphragma into the left hemithorax. Her condition did not allow us a radical surgery of Bochdalek hernia, so that we performed a palliative surgery, that is reduction of the stomach and gastrostomy. After surgery, her respiratory distress was lightened and she came to be able to ingest. She was less uncomfortable until she died due to progression of the lung cancer.

Aged↗

Development of on-site fish exposure system placed in water quality monitoring stations along a river.

Estrogen-like substances have been suspected to cause feminization of wild fish in rivers in Japan. To elucidate the influence of estrogen-like substances on fish in river, we have started to develop the on-site continuous fish exposure system using medaka Oryzias latipes that were placed in water quality monitoring stations along a river. Adult male medaka were exposed to the river water in a glass exposure tank placed in the monitoring stations. Flow rate of water and water temperature were controlled at 30 L/hour and 26 degrees C respectively, and a light: dark cycle was maintained 16:8 hours. A commercial diet free from phytoestrogens was fed 4 times in a day using automatic feeder. After 2-week exposure, hepatic vitellogenin concentration of each male medaka was measured. The exposure tests were repeatedly performed at both the upstream and the downstream of sewage treatment plants along the River Tama which is a representative urbanized river in Japan. At the control site Haijimabashi monitoring station, vitellogenin was not detected in male medaka. On the other hand, at the Ishihara monitoring station which is the most downstream in this test area, every male medaka were produced vitellogenin in the test performed in the spring of 2004. As the results of the water quality analysis, it could be inferred that the estrone derived from effluents of sewage treatment plants caused the feminization of male medaka. The reason why the concentrations of the estrone and the estrogenic activity using DNA recombinant yeast varied in proportion to the electric conductivity of river water measured at the water quality monitoring station. Furthermore, after continuous 2-week exposure, the vitellogenin production of male medaka was reduced similar to the decrease of the concentrations of the estrone and the estrogenic activity of river water.

Animal Feed↗

Electron scattering from perfluorocyclobutane (c-C4F8).

We report experimental results for electron scattering from perfluorocyclobutane, c-C(4)F(8), obtained from measurements in our two laboratories. A set of differential, integral, and momentum transfer cross sections is provided for elastic scattering for incident electron energies from 1.5 to 100 eV. Inelastic scattering (vibrational excitation) cross sections have been measured for incident electron energies of 1.5, 2, 5, 6, and 7 eV. In order to investigate the role of intermediate negative ions (resonances) in the scattering process we have also measured an excitation function for elastic scattering and vibrational excitation of the ground electronic state of C(4)F(8) for incident energies between 0.6 and 20 eV. These results are compared with the limited amount of data available in the literature for scattering from this molecule.

Journal Article↗

Electron scattering from tetrafluoroethylene.

We report experimental results for electron scattering from tetrafluoroethylene, C2F4, obtained from measurements in two laboratories. An extensive set of differential, integral, and momentum transfer cross sections is provided for elastic scattering for incident electron energies from 1 to 100 eV and inelastic (vibrational excitation) scattering for incident electron energies at 3, 6, 7.5, 8, and 15 eV, and for scattering angles ranging from 10 degrees to 130 degrees. To highlight the role of intermediate negative ions (resonances) in the scattering process we have also measured excitation functions for elastic scattering and vibrational excitation of the ground electronic state of C2F4 for incident energies between 1.5 and 20 eV. Our results are compared with recent theoretical calculations and a limited number of other experimental results.

Journal Article↗