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N Nakanishi

Publications and source records attributed to N Nakanishi.

At least 19 recordsLinked to original sources
PubMed2005

The relationship between self-reported difficulty with hearing in the worse ear and the better ear.

OBJECTIVES: To investigate the relationship of self-reported hearing difficulty with hearing in the worse ear and the better ear at 1 and 4 kHz. DESIGN: Receiver-operating characteristic (ROC) curve analysis in community-residing population. SETTINGS: The Settsu City Health Center (Osaka, Japan). PARTICIPANTS: A total of 919 consecutive participants who were provided health check-ups. MAIN OUTCOMES MEASURES: Comparison is based on the measurement of the area under the curve (AUC) of ROC. RESULTS: At 1 kHz, the area under the curve (AUC) of the worse ear (0.625 +/- 0.021) was significantly larger than that of the better ear (0.570 +/- 0.021) (P < 0.01). At 4 kHz, the AUC of the worse ear (0.665 +/- 0.019) was significantly larger than that of the better ear (0.622 +/- 0.020) (P < 0.01). Excluding the subjects with noise exposure, tinnitus and ear disease, at both frequencies, the AUC of the worse ear was not significantly larger than that of the better ear at both 1 and 4 kHz. Hearing in the worse ear was significantly more related to self-reported hearing difficulty than in the better ear without excluding those with noise exposure, tinnitus and ear disease. CONCLUSIONS: ROC curve analysis would provide a method to help us judge the difference between the worse hearing ear and the better hearing ear on the subject of hearing loss.

Adult↗
PubMed2004

Lattice imaging in low-angle and high-angle bright-field scanning transmission electron microscopy.

Atomic resolution low-angle bright-field (LABF) scanning transmission electron-microscope (STEM) images and high-angle bright-field (HABF) STEM images of [011]-orientated Si have been experimentally obtained together with high-angle annular dark-field (HAADF) STEM images. The contrast formation mechanisms of the LABF STEM and HABF STEM images are examined in comparison with HAADF STEM images. The HABF STEM images independent of defocus and thickness have spatial resolution comparable with HAADF STEM images, and are shown to be given as a simple convolution under the non-dispersion approximation of localized Bloch waves.

Journal Article↗
PubMed2004

Daily life activity and risk of developing impaired fasting glucose or type 2 diabetes in middle-aged Japanese men.

AIMS/HYPOTHESIS: The aim of this study was to investigate the association between daily life activity and risk of developing diabetes. METHODS: The study population included 2924 Japanese male office workers aged 35 to 59 years who did not have IFG (fasting plasma glucose level 6.1-6.9 mmol/l), type 2 diabetes (fasting plasma glucose level > or =7.0 mmol/l and/or medication for diabetes) or a history of cardiovascular disease, and were not receiving medication for hypertension. A 1-day activity record during an ordinary weekday was used to estimate daily energy expenditure. Fasting glucose levels were measured at annual health examinations performed in May from 1994 to 2001. RESULTS: Over a 7-year follow-up period the relative risk of IFG and type 2 diabetes decreased with increasing daily energy expenditure after controlling for potential predictors of diabetes (p<0.001 and p=0.001 for trend respectively). The age-adjusted relative risk of IFG or type 2 diabetes decreased with increasing energy expenditure on occupational physical activity, brisk walking, riding on vehicles (standing position) to and from work and other physical activities (all p<0.001 for trend). The association with riding on vehicles (standing position) and other physical activities remained after controlling for other potential confounders of diabetes (p=0.026 and p=0.003 for trend respectively). Results of stratified analyses by the presence or absence of different risk factors for diabetes revealed that the risk of IFG or type 2 diabetes was inversely related to daily energy expenditure both in men at low risk of diabetes and those at high risk. CONCLUSIONS/INTERPRETATION: Physical activity in daily life is inversely associated with the risk of developing IFG or type 2 diabetes.

Activities of Daily Living↗
PubMed2004

Quantitative high-resolution HAADF-STEM analysis of inversion boundaries in Sb(2)O(3)-doped zinc oxide.

[Formula: see text] -doped ZnO crystals including inversion boundaries were investigated by high-resolution high-angle annular-dark field (HAADF) scanning transmission electron microscopy (STEM). The images were analysed with the aid of the image simulation based on Bethe method and also the retrieval processing using deconvolution. Utility of these two approaches for the HAADF-STEM analysis is discussed.

Journal Article↗
PubMed2004

Role of surface amorphous film in high-resolution high-angle annular dark field STEM imaging.

A different scheme for high-angle annular dark-field scanning transmission electron microscopy image calculation of multilayers, such as a crystal covered by amorphous films, has been developed, in which intensities of electrons collected by an annular detector at each layer are evaluated by two kinds of optical potential for thermal diffuse scattering on the layer-by-layer representation. One beam condition caused by an amorphous structure changes the present method into a simplified method. Through a molecular dynamics study of amorphous SiO2, it is found that an off-axis cristobalite, regarded as one-beam condition, can be used for a model of amorphous SiO2 structure. Furthermore, we demonstrate how surface amorphous films adhering to a crystal reduce image contrast and show that a top surface amorphous film acts as changing defocus in coherent convergent electron beam.

Journal Article↗
PubMed2004

Haematocrit and risk of development of Type 2 diabetes mellitus in middle-aged Japanese men.

AIMS: To investigate the association between haematocrit and risk of development of diabetes. Methods The study enrolled 2953 normoglycaemic [fasting plasma glucose (FPG) < 6.1 mmol/l and taking no hypoglycaemic medication] Japanese men aged 35-59 years and free of medication for hypertension and history of cardiovascular disease. FPG was measured at periodic annual health examinations from May 1994 through May 2001. Men in whom Type 2 diabetes mellitus (FPG > or = 7.0 mmol/l or receiving hypoglycaemic medication) was found during repeated surveys were classified as having Type 2 diabetes. RESULTS: The estimated incidence rates for Type 2 diabetes during 7 years of follow-up were 3.1% [[95% confidence interval (CI) 1.6, 4.6]], 4.6% (2.8, 6.4), 5.0% (3.2, 6.9), 6.4% (4.4, 8.5), and 11.5% (8.9, 14.2) for respective haematocrit levels of < 42.6, 42.6-44.0, 44.1-45.3, 45.4-46.8, and >/= 46.9% (the log-rank test: P < 0.001). After controlling for potential predictors of diabetes, the respective relative risks for Type 2 diabetes were 1.0 (reference), 1.52 (95% CI 0.81, 2.86), 1.24 (0.66, 2.31), 1.57 (0.86, 2.88), and 2.30 (1.30, 4.08) (P for trend = 0.002). From stratified analyses by presence or absence of a risk factor, a linear association of haematocrit level with risk of development of Type 2 diabetes was also observed. CONCLUSION: These results indicate that haematocrit contributes to the risk of developing Type 2 diabetes.

Adult↗
PubMed2003

Serum uric acid and risk for development of hypertension and impaired fasting glucose or Type II diabetes in Japanese male office workers.

We examined the association of serum uric acid (SUA) with development of hypertension (blood pressure > or = 140/90 mmHg and/or medication for hypertension) and impaired fasting glucose (IFG) (a fasting plasma glucose level 6.1-6.9 mmol/l) or Type II (non-insulin-dependent) diabetes (a fasting plasma glucose level > or = 7.0 mmol/l and/or medication for diabetes) over a 6-year follow-up among 2310 Japanese male office workers aged 35-59 years who did not have hypertension, IFG, Type II diabetes, or past history of cardiovascular disease at study entry. After controlling for potential predictors of hypertension and diabetes, the relative risk for hypertension compared with quintile 1 of SUA level was 1.27 [95% confidence interval (CI): 1.00-1.62] for quintile 2, 1.34 (95% CI: 1.08-1.74) for quintile 3, 1.48 (95% CI: 1.18-1.89) for quintile 4, and 1.58 (95% CI: 1.26-1.99) for quintile 5 (p for trend <0.001). The respective multivariate-adjusted relative risks for IFG or Type II diabetes compared with quintile 1 of SUA level were 1.55 (95% CI: 0.95-2.63), 1.62 (95% CI: 0.98-2.67), 1.61 (95% CI: 1.01-2.58), and 1.78 (95% CI: 1.11-2.85) (p for trend = 0.030). The association between SUA level and risk for hypertension and IFG or Type II diabetes was stronger among men with a body mass index (BMI) <24.2 kg/m2 than among men with a BMI > or = 24.2 kg/m2, although the absolute risk was greater in more obese men. These results indicate that SUA level is closely associated with an increased risk for hypertension and IFG or Type II diabetes.

Adult↗
PubMed2003

Association of alcohol consumption with white blood cell count: a study of Japanese male office workers.

OBJECTIVES: To investigate the association of alcohol consumption with white blood cell (WBC) count. DESIGN: Cross-sectional study. SETTING: A work site in Japan. SUBJECTS: A total of 5218 Japanese male office workers aged 23-59 years who participated in annual health examinations. MAIN OUTCOME MEASURES: Subjects were classified as nondrinkers, or current drinkers who averaged <12, 12-22, 23-34, 35-45, 46-68 or > or = 69 g day(-1) of ethanol. The association between alcohol consumption and WBC count was examined by smoking status. RESULTS: After controlling for age, body mass index, systolic blood pressure, and levels of total cholesterol, high-density lipoprotein (HDL) cholesterol and fasting plasma glucose, WBC count showed a negative dose-response relation with alcohol consumption in each smoking status. The WBC count increment per category of alcohol intake (x10(9) cells L(-1)) was -0.07 [95% confidence interval (CI), -0.11 to -0.04] for never smokers, -0.11 (95% CI, -0.15 to -0.06) for ex-smokers, and -0.04 (-0.08 to -0.00) for current smokers. For current smokers, additional adjustment for cigarettes smoked per day heightened the magnitude of these associations [the respective WBC count increment (x10(9) cells L(-1)), -0.07 (95% CI, -0.11 to -0.03)]. The risk for high WBC count (fifth quintile) also showed a negative linear trend related to alcohol intake in each smoking status. CONCLUSIONS: The WBC count was inversely associated with alcohol consumption in both nonsmokers and smokers. In view of the firm association of WBC count with the increased risk of coronary heart disease, alcohol consumption seems to have a favourable impact on the link between WBC count and the risk of cardiovascular disease.

Adult↗
PubMed2003

Serum gamma-glutamyltransferase and development of impaired fasting glucose or type 2 diabetes in middle-aged Japanese men.

OBJECTIVE: To investigate the association between serum gamma-glutamyltransferase (GGT) and risk for development of diabetes. DESIGN: Longitudinal study (followed from 1994 to 2001). SETTING: A work site in Japan. SUBJECTS: A total of 2918 Japanese male office workers aged 35-59 years who did not have impaired fasting glucose (IFG) (a fasting plasma glucose concentration of 6.1-6.9 mmol L-1), type 2 diabetes (a fasting plasma glucose concentration of >/=7.0 mmol L-1 or receipt of hypoglycaemic medication), medication for hypertension or hepatitis, alanine aminotransferase concentrations higher than three times the upper limit of the reference range or a history of cardiovascular disease at study entry. MAIN OUTCOME MEASURE: Incidence of IFG or type 2 diabetes over a 7-year period. RESULTS: With adjustment for potential risk factors for diabetes, the relative risk for IFG compared with serum GGT <16 U L-1 was 1.23 (95% CI, 0.79-1.90), 1.50 (CI, 0.97-2.32) and 1.70 (CI, 1.07-2.71) with serum GGT of 16-24, 25-43 and >/=44 U L-1, respectively (P for trend = 0.014). The respective relative risks for type 2 diabetes compared with serum GGT <16 U L-1 were 2.54 (CI, 1.29-5.01), 2.64 (CI, 1.33-5.23) and 3.44 (CI, 1.69-6.70) (P for trend = 0.002). From stratified analyses by body mass index (BMI) and alcohol intake, a stronger linear association between serum GGT and development of IFG or type 2 diabetes was found in men with a BMI >/=23.2 kg m-2 in both those who drank <46 and >/=46 g day-1 of ethanol. CONCLUSIONS: The risk for development of IFG or type 2 diabetes increased in a dose-dependent manner as serum GGT increased in middle-aged Japanese men. The increased relative risk for IFG or type 2 diabetes associated with serum GGT was more pronounced in obese men.

Adult↗
PubMed2002

White blood-cell count and the risk of impaired fasting glucose or Type II diabetes in middle-aged Japanese men.

AIMS/HYPOTHESIS: To investigate the association between white blood-cell (WBC) count and the development of diabetes, independent of cigarette smoking. METHODS: We examined 2953 Japanese men who were office workers and between 35 and 59 years of age and who did not have impaired fasting glucose (IFG) (a fasting glucose concentration of 6.1-6.9 mmol/l), Type II (non-insulin-dependent) diabetes mellitus (a fasting glucose concentration of > or =7.0 mmol/l or more or receipt of hypoglycaemic medication), medication for hypertension, and a history of cardiovascular disease. Fasting glucose concentrations were measured at annual health examinations from May 1994 through May 2000. RESULTS: After controlling for potential predictors of diabetes, the relative risk for IFG or Type II diabetes mellitus compared with a WBC count of less than 5.3-10(9) cells/l was 1.2 (95 %-CI, 0.6-2.3), 1.6 (CI, 0.8-3.1), and 2.5 (CI, 1.2-5.1) among non-smokers (p for trend = 0.009): and 1.0 (CI, 0.4-2.5), 2.3 (CI, 1.0-5.1), and 3.1 (CI, 1.4-7.1) among ex-smokers (p for trend = 0.001) with WBC counts of 5.3-6.1, 6.2-7.2, and 7.3-10(9) cells/l or more, respectively. Among current smokers, the respective multivariate-adjusted relative risks for IFG or Type II diabetes mellitus were 1.1 (CI, 0.6-2.1), 1.4 (CI, 0.8-2.4), and 1.2 (CI, 0.7-2.1) (p for trend = 0.460). CONCLUSION/HYPOTHESIS: Although the selection of a rigorously normoglycaemic cohort might have had an influence on these observations, higher WBC counts seem to predict the development of IFG or Type II diabetes mellitus, primarily in non-smokers.

Adult↗
PubMed2002

Deconvolution processing of HAADF STEM images.

A deconvolution processing of high-resolution high-angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images, combined with maximum entropy method, is applied to two experimental [0 11]-Si images; one having unresolved dumbbells and the other having resolved dumbbells and artificial bright spots. The deconvoluted images for these images show bright spots corresponding to the projected atomic columns and no artificial bright spots. Thus, the deconvolution processing provides almost a real projected atomic structure by eliminating effects of the probe function from HAADF STEM images.

Journal Article↗
PubMed2002

White blood cell count and clustered features of metabolic syndrome in Japanese male office workers.

We assessed the association of white blood cell (WBC) count with different components of metabolic syndrome (MS)-obesity, hypertension, hypercholesterolemia, low high-density lipoprotein cholesterol levels, hypertriglyceridemia, high fasting plasma glucose levels and hyperuricemia-in 5275 Japanese male office workers aged 23-59 years. After controlling for age, smoking and alcohol intake, the relative risks for the presence of 1, 2, 3, 4 and > or =5 features of MS compared with the lowest quintile of WBC count increased in a dose-dependent manner as WBC count increased (P for trend < 0.001 for all) and the increased relative risks for clustered features of MS were more pronounced as the number of features of MS increased. The WBC count increments in subjects with 1, 2, 3, 4 and > or =5 features of MS were 0.28, 0.45, 0.68, 0.76 and 1.40 x10(9) cells/l, respectively, compared with the subjects without features of MS (P for trend < 0.001). These findings indicate a strong association between WBC count and clustered features of MS in middle-aged Japanese men.

Adult↗
PubMed2002

Oral beraprost sodium improves exercise capacity and ventilatory efficiency in patients with primary or thromboembolic pulmonary hypertension.

OBJECTIVE: To investigate the effect of beraprost sodium, an orally active prostacyclin analogue, on exercise capacity and ventilatory efficiency in patients with primary pulmonary hypertension and chronic thromboembolic pulmonary hypertension. PATIENTS AND DESIGN: Symptom limited cardiopulmonary exercise testing was performed before and 3 (1) months (mean (SEM)) after beraprost treatment in 30 patients with precapillary pulmonary hypertension (14 with primary pulmonary hypertension and 16 with chronic thromboembolic pulmonary hypertension). RESULTS: Long term treatment with beraprost resulted in significant increases (mean (SEM)) in peak workload (87 (4) W to 97 (5) W, p < 0.001) and peak oxygen consumption (peak VO2, 14.9 (0.7) ml/kg/min to 16.8 (0.7) ml/kg/min, p < 0.001). Beraprost decreased the ventilatory response to carbon dioxide production during exercise (VE-VCO2 slope, 42 (2) to 37 (1), p < 0.001). No significant difference in the responses of these variables to beraprost treatment was observed between patients with primary pulmonary hypertension and chronic thromboembolic pulmonary hypertension. CONCLUSIONS: Oral administration of beraprost sodium may improve exercise capacity and ventilatory efficiency in patients with both primary and chronic thromboembolic pulmonary hypertension.

Administration, Oral↗
PubMed2001

K(ATP) channels predominantly regulate conduit vessel tone in normoxic cat pulmonary arteries in vivo.

Through our investigations of the intact pulmonary circulation, we aimed to find out whether K(ATP) channels contribute to regulating basal vascular tone and to clarify which vascular segments dilate during K(ATP) channel activation under basal tone conditions. Using an X-ray television system on anesthetized cat lungs, we measured internal diameter (ID) responses to two K(ATP) channel inhibitors (glibenclamide and 4-morpholinecarboximidine-N-1-adamantyl-N'-cyclohexyl-hydrochloride (U-37883A)) and to an activator (levcromakalim) in normoxic pulmonary arteries. In conduit arteries (800-3000 microm ID), the inhibitors and activator induced larger ID constrictions (14-17%) and dilatations (29-32%), respectively. However, in resistance arteries (<500 microm), the constriction response was negligible and the dilatation response relatively small (5-10%). The data suggest that K(ATP) channels are active and capable of regulating basal vascular tone primarily within conduit pulmonary arteries even though these channels are present in all pulmonary arteries.

Adamantane↗
PubMed2001

Synthesis, crystal structure, and thermolysis of the first tetracoordinate 1lambda4,2-selenazetidines: aziridine formation reaction from a four-membered heterocycle bearing highly coordinate selenium.

[structure: see text]. The first tetracoordinate 1lambda4,2-selenazetidines were synthesized by taking advantage of the Martin ligand and characterized by X-ray crystallographic analysis. The selenazetidines gave the corresponding aziridine and the cyclic selenenate on their thermolysis, which indicates the possibility that a highly coordinate 1,2-heterachalcogenetane may provide the corresponding heteracyclopropane regardless of the heteroatoms.

Journal Article↗
PubMed2001

Clinical characteristics of acute pulmonary thromboembolism in Japan: results of a multicenter registry in the Japanese Society of Pulmonary Embolism Research.

BACKGROUND: Although the incidence of acute pulmonary thromboembolism (APTE) has been increasing in Japan, patient characteristics, management strategies, and outcome have not yet been assessed in large series. HYPOTHESIS: The present study was designed to investigate the current status of APTE in Japan. METHODS: Of a total of 533 registry patients with pulmonary thromboembolism, 309 with APTE were analyzed with respect to clinical symptoms and signs, predisposing factors, diagnostic procedures, estimation of deep venous thrombosis, treatment, and clinical course. RESULTS: Main risk factors were recent major surgery, cancer, prolonged immobilization, and obesity; only a few patients had coagulopathy and 36% were in cardiogenic shock at presentation. The majority of registry patients underwent lung scans or pulmonary angiography; 30% were diagnosed only by lung scanning. Venous ultrasonography was used in only 34 patients, while 188 patients underwent at least one diagnostic procedure for deep venous thrombosis. Thrombolysis was more frequently performed in patients with cardiogenic shock, and only a few patients received thromboembolectomy. In-hospital mortality rate was 14%. In patients with cardiogenic shock, the mortality rate was reduced by thrombolysis. The predictors of in-hospital mortality were male gender, cardiogenic shock, cancer, and prolonged immobilization. CONCLUSIONS: The patients in this registry had almost the same findings as those in Western patients, except for some points that had the possibility of demonstrating a difference between Westerners and Japanese in the development of APTE. These results can prove especially helpful in planning prospective, randomized trials that will clarify the impact of widely used treatment modalities on the outcome of patients with APTE.

Age Distribution↗
PubMed2001

Pulmonary artery reflection for differentially diagnosing primary pulmonary hypertension and chronic pulmonary thromboembolism.

OBJECTIVES: The purpose of this investigation was to differentiate chronic pulmonary thromboembolism (CPTE) from primary pulmonary hypertension (PPH) by means of the indexes of pulmonary arterial reflection. BACKGROUND: These differences in the primary lesions would make pulmonary artery reflection occur earlier in CPTE than in PPH. Although the analysis of pulsatility of pulmonary arterial pressure is useful in the differential diagnosis of PPH and CPTE, it is not known whether the analysis of pulmonary artery reflection can differentiate CPTE from PPH. METHODS: Since CPTE predominantly involves the proximal arteries, whereas PPH involve the peripheral arteries, we hypothesized that patients with CPTE have a large augmentation index and a short inflection time. For this study, we enrolled 62 patients who had CPTE (31 patients) and PPH (31 patients). We measured pulmonary arterial pressure using a fluid filled system that included a balloon-tipped flow directed catheter. To quantify the pulmonary artery reflection, we used the augmentation index and inflection time. RESULTS: The augmentation index was markedly higher in CPTE than it was in PPH (27.4% +/- 15.2% [SD] and -25.1% +/- 26.9%, respectively, p < 0.001) and was diagnostic in separating the two groups. Inflection time separated the two groups reasonably well (97 +/- 20 ms and 210 +/- 49 ms, respectively, p < 0.001). CONCLUSIONS: The analysis of pulmonary arterial reflection is useful in the differential diagnosis of CPTE and PPH.

Adult↗