Yoshinari Yasuda

Chubu University, Nagoya-shi, Aichi-ken, Japan

Are you Yoshinari Yasuda?

Claim your profile

Publications (67)209.54 Total impact

  • Article: Comparison of oxygen desaturation patterns in children and adults with sleep-disordered breathing.
    [show abstract] [hide abstract]
    ABSTRACT: PURPOSE: Although the number of apnea-hypopnea episodes per hour apnea-hypopnea index (AHI) is typically used to evaluate sleep-disordered breathing (SDB) in adults, it does not provide an accurate characterization of SDB in children. We investigated differences in SDB patterns in children and adults to evaluate SDB severity in children. MATERIALS AND METHODS: Fifteen adults (mean age, 45.3±8.4years) and 15 children (mean age, 6.7±3.9years) with adenotonsillar hypertrophy underwent standard polysomnography. The change of oxygen saturation (ΔSpO2) was defined as the difference between baseline SpO2 during stable nighttime breathing and the lowest SpO2 accompanied by an apnea-hypopnea event. The number of apnea-hypopnea episodes was determined using two different criteria to define an episode (criterion 1: cessation of airflow for at least 10s; criterion 2: cessation of airflow for at least two consecutive breaths). RESULTS: Mean ΔSpO2 accompanied by obstructive apneas lasting ≤10s was significantly greater in children than in adults, although there was no significant difference in the duration of apnea-hypopnea episodes. The slope of the regression line between ΔSpO2 and apnea-hypopnea duration in children was greater than in adults (P<0.005). AHI in children was higher when calculated using criterion 2 compared to criterion 1 (10.9±9.4 vs. 6.5±4.9/h, P=0.003). CONCLUSIONS: ΔSpO2 is a good indicator of SDB severity in children, and should therefore be considered in the diagnosis and treatment of pediatric SDB along with AHI.
    American journal of otolaryngology 02/2013; · 0.77 Impact Factor
  • Article: Therapeutic Strategies for Sleep Apnea in Hypertension and Heart Failure.
    Akiko Noda, Seiko Miyata, Yoshinari Yasuda
    [show abstract] [hide abstract]
    ABSTRACT: Sleep-disordered breathing (SDB) causes hypoxemia, negative intrathoracic pressure, and frequent arousal, contributing to increased cardiovascular disease mortality and morbidity. Obstructive sleep apnea syndrome (OSAS) is linked to hypertension, ischemic heart disease, and cardiac arrhythmias. Successful continuous positive airway pressure (CPAP) treatment has a beneficial effect on hypertension and improves the survival rate of patients with cardiovascular disease. Thus, long-term compliance with CPAP treatment may result in substantial blood pressure reduction in patients with resistant hypertension suffering from OSAS. Central sleep apnea and Cheyne-Stokes respiration occur in 30-50% of patients with heart failure (HF). Intermittent hypoxemia, nocturnal surges in sympathetic activity, and increased left ventricular preload and afterload due to negative intrathoracic pressure all lead to impaired cardiac function and poor life prognosis. SDB-related HF has been considered the potential therapeutic target. CPAP, nocturnal O2 therapy, and adaptive servoventilation minimize the effects of sleep apnea, thereby improving cardiac function, prognosis, and quality of life. Early diagnosis and treatment of SDB will yield better therapeutic outcomes for hypertension and HF.
    Pulmonary medicine. 01/2013; 2013:814169.
  • Article: A Decade After the KDOQI CKD Guidelines: A Perspective From Japan.
    Enyu Imai, Yoshinari Yasuda, Seiichi Matsuo
    American Journal of Kidney Diseases 11/2012; 60(5):729-30. · 5.43 Impact Factor
  • Article: Performance of GFR equations in Japanese subjects.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND: Japanese GFR equations based on serum creatinine (Scr) (Eq(cr)), serum cystatin C (Scys) (Eq(cys)) and average value of Eq(cr) and Eq(cys) (Eq(average)), and coefficient-modified CKD-EPI equations based on Scr (CKD-EPI(cr)), Scys (CKD-EPI(cys)) and Scys in combination with Scr (CKD-EPI(cr-cys)) are now available for Japanese subjects. Performance of these equations has not been well evaluated in subjects stratified by GFR. Therefore, the bias, precision and accuracy of the GFR equations were compared in Japanese subjects stratified by measured GFR. METHODS: Three hundred fifty Japanese subjects were included for validation. These subjects were stratified by measured GFR (0-29, 30-59, 60-89, 90-119 ml/min/1.73 m(2) and total). Japanese equations (Eq(cr), Eq(cys) and Eq(average)) were compared with coefficient-modified CKD-EPI equations (0.813 × CKD-EPI(cr), CKD-EPI(cys) and 0.908 × CKD-EPI(cr-cys)), respectively. GFR was measured by inulin renal clearance. Standardized Scr was measured by enzymatic method. Standardized Scys was measured by colloidal gold immunoassay. RESULTS: Bias and accuracy were not significantly different between Japanese GFR equations and coefficient-modified CKD-EPI equations in all mGFR ranges. The precision of Eq(cr) was significantly better in GFR 0-29 ml/min/1.73 m(2) and significantly worse in GFR 60-89 and GFR 90-119 ml/min/1.73 m(2) compared with 0.813 × CKD-EPI(cr). The precision of Eq(cys) was significantly better in GFR 30-59 and GFR 60-89 ml/min/1.73 m(2) compared with CKD-EPI(cys). The precision of Eq(average) was significantly better in GFR 30-59 ml/min/1.73 m(2) and significantly worse in GFR 90-119 ml/min/1.73 m(2) compared with 0.908 × CKD-EPI(cr-cys). CONCLUSION: Japanese GFR equations performed well in subjects with GFR under 60 ml/min/1.73 m(2) compared with the coefficient-modified CKD-EPI equations.
    Clinical and Experimental Nephrology 10/2012; · 1.37 Impact Factor
  • Article: GFR Estimation Using Standardized Serum Cystatin C in Japan.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND: Recently, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) developed glomerular filtration rate (GFR)-estimating equations based on standardized serum cystatin C (CKD-EPI(cys)) and standardized serum creatinine plus standardized serum cystatin C (CKD-EPI(cr-cys)). We developed new GFR-estimating equations based on standardized cystatin C for a Japanese population and compared their accuracy with the CKD-EPI equations. STUDY DESIGN: Accuracy of diagnostic test study. SETTING & PARTICIPANTS: 413 (development data set) and 350 individuals (validation data set). INDEX TEST: CKD-EPI(cys); CKD-EPI(cr-cys); modifications to CKD-EPI(cys) and CKD-EPI(cr-cys) using Japanese coefficients; and newly developed Japanese eGFR equations based on standardized serum cystatin C (Eq(cys)), cystatin C with a nonrenal factor reflecting hypothesized extrarenal elimination (Eq(cys+nonrenal)), and creatinine in combination with cystatin C (Eq(cr-cys)). Standardized cystatin C values were determined by a colloidal gold immunoassay traceable to the international certified reference material ERM-DA471/IFCC. REFERENCE TEST: Measured GFR by inulin renal clearance. RESULTS: In a development data set, we calculated Japanese coefficients for CKD-EPI(cys) and CKD-EPI(cr-cys) of 0.977 (95% CI, 0.853-1.002) and 0.908 (95% CI, 0.889-0.928), respectively. In a validation data set, we compared CKD-EPI(cys), Eq(cys), and Eq(cys+nonrenal) with each other. Bias and accuracy were not significantly different among the 3 equations. The precision of CKD-EPI(cys) was significantly better than for Eq(cys) (P = 0.007) and not significantly different from Eq(cys+nonrenal) (P = 0.6). We then compared 0.908 × CKD-EPI(cr-cys), Eq(cr-cys), and Eq(average) (the average value of Eq(cr) [previous Japanese equation based on standardized serum creatinine] and Eq(cys+nonrenal)) with each other in the validation data set. Bias and accuracy were not significantly different among the 3 equations. The precision of 0.908 × CKD-EPI(cr-cys) was significantly better than for Eq(cr-cys) (P = 0.004) and not significantly different from Eq(average) (P = 0.06). LIMITATIONS: Limited number of participants with measured GFR >90 mL/min/1.73 m(2). Extrarenal elimination of cystatin C was not measured. CONCLUSIONS: CKD-EPI(cys) performed well in Japanese individuals, suggesting that equations based on serum cystatin C could be used in patients with different races without modification. Accounting for extrarenal elimination of cystatin C may improve the performance of estimating equations.
    American Journal of Kidney Diseases 08/2012; · 5.43 Impact Factor
  • Article: Pharmacokinetic study of S-1 in patients in whom inulin clearance was measured.
    [show abstract] [hide abstract]
    ABSTRACT: This pharmacokinetic study of S-1 was conducted in patients in whom glomerular filtration rate (GFR) was directly measured to explore the possibility of adjusting the S-1 dose on the basis of GFR in patients with normal or nearly normal renal function. S-1 was given to 12 patients twice daily for 28 consecutive days followed by 14 days of rest, repeated every 6 weeks. GFR was measured on the basis of inulin clearance (CLin) before the first day of treatment. The area under the time-concentration curve (AUC) of 5-fluorouracil (5-FU) correlated with that of 5-chloro-2,4-dihydroxypyridine (CDHP, r = 0.750, p = 0.005). The AUC of CDHP correlated with the measured 24-hour creatinine clearance (CLcr) per subject (r = -0.620, p = 0.032), but not with the CLin (r = -0.356, p = 0.257). The AUC of 5-FU did not correlate with either the 24-hour CLcr per subject (r = -0.401, p = 0.187) or with the CLin (r = -0.300, p = 0.351). Dosage adjustment based on the GFR does not reduce individual variations in 5-FU concentrations among patients with normal or nearly normal renal function who receive S-1.
    Oncology 06/2012; 83(1):38-44. · 2.27 Impact Factor
  • Article: Complete remission within 2 years predicts a good prognosis after methylprednisolone pulse therapy in patients with IgA nephropathy.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND: Pozzi et al. reported the effectiveness of steroid pulse therapy (Pozzi's regimen) in IgA nephropathy (IgAN). The present study was performed to clarify the predictive factors for IgAN patients treated with Pozzi's regimen. METHODS: One hundred nine IgAN patients treated by Pozzi's regimen were observed for up to 112.6 (median 39.7) months, and remission of proteinuria (PR) and disappearance of urinary abnormalities [complete remission (CR)] after Pozzi's regimen were analyzed. Predictive factors for the glomerular filtration rate (GFR) slopes for up to 5 years were analyzed among 81 patients who were observed for at least 2 years. The outcome of a 50 % increase in sCr was compared between the CR and non-CR groups within 2 years. RESULTS: Cumulative PR and CR rates increased rapidly until 2 years (54.5 and 46.8 % at 2 years), and then slowly but steadily up to 6 years (72.8 and 66.4 % at 6 years). Baseline characteristics of the CR and non-CR groups within 2 years were similar except for proteinuria. GFR slope was steeper in the non-CR group than in the CR group (-2.44 ± 5.12 vs. -0.32 ± 3.34 ml/min/1.73 m(2)/year). On multivariate analysis, sex and CR within 2 years were associated with GFR slope. Kaplan-Meier analysis demonstrated a better survival rate in CR group patients without a 50 % increase in sCr (p = 0.024). CONCLUSIONS: Among IgAN patients treated with Pozzi's regimen, CR within 2 years predicts a good prognosis.
    Clinical and Experimental Nephrology 05/2012; · 1.37 Impact Factor
  • Article: Percutaneous coronary intervention with bare metal stent vs. drug-eluting stent in hemodialysis patients.
    [show abstract] [hide abstract]
    ABSTRACT: Percutaneous coronary intervention (PCI) with drug-eluting stent (DES) is widely performed in patients with coronary artery disease, but the high restenosis rate remains a major clinical problem after implantation of DES in patients on hemodialysis (HD). Until now, there are limited reports regarding the long-term clinical outcome after implantation of DES in this patient population. We compared bare metal stent (BMS) and DES for long-term clinical outcomes, such as target lesion revascularization (TLR), in HD patients undergoing PCI. BMS and DES were implanted in 204 and 301 patients, respectively. Baseline and lesion characteristics were comparable between the 2 groups. By Kaplan-Meier analysis, event rates of major adverse cardiac events for 6 years were significantly lower in the DES group than in the BMS group (42.5% vs. 58.0%, P=0.036). Although there were no significant differences in TLR rates between patients treated with DES and those with BMS at 1 year after PCI (17.8% vs. 21.3%, P=0.32), patients treated with DES had significantly lower rates of TLR compared with those treated with BMS beyond the 1-year follow-up after PCI (16.4% vs. 30.9%, P=0.019). In patients on HD, implantation of DES might be more effective for preventing TLR in the medium to long follow-up period than BMS, although restenosis after PCI with DES is common in the short term.
    Circulation Journal 04/2012; 76(7):1609-15. · 3.77 Impact Factor
  • Article: Ethnic factors of the glomerular filtration rate estimating equation.
    Masaru Horio, Yoshinari Yasuda, Enyu Imai
    Kidney International 04/2012; 81(8):799; author reply 799-800. · 6.61 Impact Factor
  • Article: A rare case of acute kidney injury associated with autoimmune hemolytic anemia and thrombocytopenia after long-term usage of oxaliplatin.
    [show abstract] [hide abstract]
    ABSTRACT: Oxaliplatin is effective in advanced colorectal cancer and is known to have relatively few side effects, such as hemolysis and renal toxicity. We report a case of acute kidney injury (AKI) after treatment with a combination of oxaliplatin, folinic acid and 5-fluorouracil or capecitabine. The patient developed acute renal failure, hemolytic anemia and thrombocytopenia after the 34th course of chemotherapy including oxaliplatin. A positive direct antiglobulin test and detection of immunoglobulin G and complement C3b and C3d on erythrocytes suggested the diagnosis of immune-related severe intravascular hemolytic anemia. She was successfully treated and recovered using plasma exchange, corticosteroids and hemodialysis therapy. Only seven other cases of AKI associated with oxaliplatin use have been reported to date. As in this case, acute hemolysis due to autoimmune mechanisms and subsequent AKI occurred suddenly after frequent use of oxaliplatin in four of those cases. We should be aware that oxaliplatin may cause sudden life-threatening hemolysis by drug-induced antibodies and subsequent AKI, even though oxaliplatin is frequently administered without side effects. This represents the first case report of AKI-related hemolysis due to oxaliplatin in Japan.
    Clinical and Experimental Nephrology 03/2012; 16(3):490-4. · 1.37 Impact Factor
  • Article: Performance of the Japanese GFR equation in potential kidney donors.
    [show abstract] [hide abstract]
    ABSTRACT: Japanese GFR equation was developed from mainly chronic kidney disease (CKD) subjects. Only a small number of healthy subjects were included in the development and validation of the GFR equation. We assessed the performance of the equation in potential kidney donors. A total of 113 potential kidney donors was included. The data of CKD subjects that were previously reported were also included for comparison. GFR (mGFR) was measured by inulin clearance. The estimated GFR (eGFR) was calculated by the Japanese GFR equation. Bias of the equation (eGFR - mGFR) and urinary creatinine excretion were evaluated. There was no significant difference between eGFR and mGFR in 340 CKD subjects (54.2 ± 31.6 and 55.7 ± 33.2 ml/min/1.73 m(2), respectively). Contrarily, the eGFR was significantly lower than mGFR in 113 potential kidney donors (78.9 ± 16.2 and 93.6 ± 19.2 ml/min/1.73 m(2), respectively). The biases in potential kidney donors with eGFR 30-59 and 60-89 ml/min/1.73 m(2) were significantly greater than those in CKD subjects (-19.2 ± 12.2 and -18.3 ± 16.4 ml/min/1.73 m(2) in potential kidney donors and -3.8 ± 15.6 and -3.4 ± 17.6 ml/min/1.73 m(2) in CKD subjects, respectively). Creatinine excretion per body weight of potential kidney donors was significantly higher than that of CKD subjects, suggesting higher creatinine generation in potential kidney donors. The Japanese GFR equation underestimated GFR in potential kidney donors. Higher creatinine generation compared with CKD subjects may contribute to the underestimation of GFR by the Japanese GFR equation in potential kidney donors.
    Clinical and Experimental Nephrology 01/2012; 16(3):415-20. · 1.37 Impact Factor
  • Source
    Article: DNA hypermethylation and inflammatory markers in incident Japanese dialysis patients.
    [show abstract] [hide abstract]
    ABSTRACT: Inflammation is an established mortality risk factor in chronic kidney disease (CKD) patients. Although a previous report showed that uremic Caucasian patients with inflammation had signs of global DNA hypermethylation, it is still unknown whether DNA hypermethylation is linked to inflammatory markers including a marker of bacterial infections in Japanese CKD patients. In 44 consecutive incident dialysis patients (26 males, mean age 59 ± 12 years) without clinical signs of infection, global DNA methylation was evaluated in peripheral blood DNA using the HpaII/MspI ratio by the luminometric methylation assay method. A lower ratio of HpaII/MspI indicates global DNA hypermethylation. Procalcitonin (PCT), a marker of inflammation due to bacterial infections, was measured using an immunochromatographic assay. The patients were divided into hyper- and hypomethylation groups based on the median value of the HpaII/MspI ratio 0.31 (range 0.29-0.37). Whereas patients in the hypermethylation group had higher ferritin levels [133.0 (51.5-247.3) vs. 59.5 (40.0-119.0) ng/ml; p = 0.046], there were no significant differences in age, gender, diabetes, smoking, anemia or serum albumin levels. However, the HpaII/MspI ratio showed significant negative correlations with PCT (ρ = -0.32, p = 0.035) and ferritin (ρ = -0.33, p = 0.027) in Spearman's rank test. In a multiple linear regression analysis, PCT and ferritin were associated with a lower HpaII/MspI ratio (R(2) = 0.24, p = 0.013). In this study, global DNA hypermethylation was associated with ferritin and, most likely, PCT, suggesting that inflammation induced by subclinical bacterial infection promoted DNA methylation.
    Nephron extra. 01/2012; 2(1):159-68.
  • Article: Effects of carperitide on contrast-induced acute kidney injury with a minimum volume of contrast in chronic kidney disease patients.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND/AIMS: Although contrast-induced acute kidney injury (CIAKI) is a major complication associated with angiography, the prophylaxis is not well established. Use of a low dose of carperitide for preventing CIAKI remains controversial. We examined the protective effect of carperitide on CIAKI after coronary angiography with a small contrast volume in chronic kidney disease (CKD) patients with coronary artery disease. METHODS: We randomly assigned 112 consecutive patients to a carperitide or a control group. The contrast volume was kept under 150 ml. The primary endpoint was the incidence of CIAKI defined by a serum creatinine of ≥25% or a serum creatinine of ≥0.5 mg/dl from baseline within 48 h. The secondary endpoint was a change in renal function at 1 week after the procedure. Results: The baseline characteristics and contrast volumes (carperitide group: 67.4 ± 38.2 ml vs. control group: 64.8 ± 20.5 ml, p = 0.661) were comparable in the two groups. The incidence of CIAKI was similar in the two groups (carperitide group: 8.5% vs. control group: 5.7%, p = 0.564). A multivariate analysis revealed that a hypotension ≥20 mm Hg was a significant predictor of developing CIAKI in the carperitide group (p = 0.015). The incidence of CIAKI in the carperitide group without hypotension was rare, but not significantly different (carperitide group: 2.4% vs. control group: 5.7%, p = 0.432). Conclusions: This study indicated that the use of a small contrast volume suppressed the incidence of CIAKI and that carperitide had no prophylactic effect against CIAKI. Our results also revealed the impact of hypotension on the development of CIAKI in the carperitide group.
    Nephron extra. 01/2012; 2(1):303-10.
  • Article: Glomerular hyperfiltration in prediabetes and prehypertension.
    [show abstract] [hide abstract]
    ABSTRACT: This study aimed to investigate the associations of hyperfiltration and hypofiltration with prediabetes and prehypertension. The study subjects included 99 140 people aged 20-89 years who underwent health checkups in Aichi Prefecture, Japan. The prevalence of hyperfiltration [estimated glomerular filtration rate (eGFR) above the age-/sex-specific 95th percentile] and hypofiltration (eGFR below the age-/sex-specific 5th percentile) was compared among stages of prediabetes (fasting plasma glucose <100, 100-109, 110-125 and ≥126 mg/dL for no prediabetes, Stage 1 prediabetes, Stage 2 prediabetes and diabetes, respectively) and prehypertension [blood pressure (BP) <120/80, 120-129/80-84, 130-139/85-89 and ≥140/90 mmHg for no prehypertension, Stage 1 prehypertension, Stage 2 prehypertension and hypertension, respectively). The prevalence of hyperfiltration increased with increasing stage of prediabetes [odds ratios (ORs): 1.29, 1.58 and 2.47 for Stage 1 prediabetes, Stage 2 prediabetes and diabetes, respectively] and prehypertension (ORs: 1.10, 1.33 and 1.52 for Stage 1 prehypertension, Stage 2 prehypertension and hypertension, respectively). Hypofiltration was not associated with prediabetes or prehypertension. The prevalence of glomerular hyperfiltration increased with increasing stages of prediabetes and prehypertension. Therefore, kidney function should be monitored in subjects with prediabetes or prehypertension. In subjects with hyperfiltration, earlier treatment of hyperglycemia and high BP may be necessary to prevent the development of kidney damage.
    Nephrology Dialysis Transplantation 12/2011; 27(5):1821-5. · 3.40 Impact Factor
  • Source
    Article: Nuclear retention of importin α coordinates cell fate through changes in gene expression.
    [show abstract] [hide abstract]
    ABSTRACT: Various cellular stresses including oxidative stress induce a collapse of the Ran gradient, which causes accumulation of importin α in the nucleus and a subsequent block of nuclear protein import. However, it is unknown whether accumulated importin α performs roles in the nucleus after its migration in response to stress. In this study, we found that nuclear-retained importin α2 binds with DNase I-sensitive nuclear component(s) and exhibits selective upregulation of mRNA encoding Serine/threonine kinase 35 (STK35) by microarray analysis. Chromatin immunoprecipitation and promoter analysis demonstrated that importin α2 can access to the promoter region of STK35 and accelerate its transcription in response to hydrogen peroxide exposure. Furthermore, constitutive overexpression of STK35 proteins enhances caspase-independent cell death under oxidative stress conditions. These results collectively reveal that nuclear-localized importin α2 influences gene expression and contributes directly to cell fate outcomes including non-apoptotic cell death.
    The EMBO Journal 09/2011; 31(1):83-94. · 9.20 Impact Factor
  • Article: Validation of the equations for estimating daily sodium excretion from spot urine in patients with chronic kidney disease.
    [show abstract] [hide abstract]
    ABSTRACT: Measuring sodium excretion in a 24-h urine collection is the most reliable method of estimating salt intake, but it is not applicable to all patients. As an alternative, equations for estimating Na excretion from Japanese by a spot urine sample were created, but they have not been validated in patients with chronic kidney disease (CKD), which are frequently associated with nocturia and medication. We enrolled 136 patients with CKD and collected both 24-h urine and the first morning urine. Na excretion was estimated from the first morning urine by Kawasaki's equation, which was originally used for the second morning urine, and Tanaka's equation, which is applied for spot urine samples taken at any time from 9 am to 7 pm. We evaluated the two equations for bias, RMSE and accuracy within 30 and 50% of the measured Na excretion. Bias, RMSE and accuracy within 30% of the estimated Na excretion were 48 ± 69 and 2 ± 69 mmol/day, 84 and 69 mmol/day, and 35 and 49% using Kawasaki's equation and Tanaka's equation, respectively. Na excretion in the first morning urine was accurately estimated by Tanaka's equation, but it was overestimated by Kawasaki's equation. Nocturia and medication such as diuretics and ACE inhibitor or angiotensin receptor blocker did not affect the accuracy with which Na excretion was estimated by Tanaka's equation substantially. Tanaka's equation for estimating Na excretion from the first morning urine in patients with CKD is accurate enough for use in clinical practice.
    Clinical and Experimental Nephrology 09/2011; 15(6):861-7. · 1.37 Impact Factor
  • Article: Performance of serum cystatin C versus serum creatinine as a marker of glomerular filtration rate as measured by inulin renal clearance.
    [show abstract] [hide abstract]
    ABSTRACT: Serum cystatin C was recently proposed as an alternative marker of glomerular filtration rate (GFR), with a suggested better performance than creatinine. However, detailed studies are limited. We evaluated the performance of cystatin C as a GFR marker. GFR was measured by inulin clearance in 763 Japanese subjects. Factors other than GFR influencing serum cystatin C or serum creatinine were analyzed by multivariate analyses. After adjustment for GFR, the value of serum creatinine was 25.2% lower in females than males, and decreased by 5.2% for every 20 years of age. Serum cystatin C was 8.2% lower in females, and did not change significantly with aging. Creatinine but not cystatin C was significantly affected by body weight, height and body mass index after adjustment for GFR, gender and age. The correlation coefficient between GFR and 1/cystatin C was significantly higher than that of 1/creatinine in total subjects (0.866 and 0.810, respectively, p < 0.001). Unlike serum creatinine, serum cystatin C did not increase in association with the reduction of GFR in subjects with very low GFR. The regression line of 1/cystatin C against GFR showed a significantly negative intercept of about -8 ml/min/1.73 m(2). The performance of serum cystatin C was not good in the subjects with very low GFR. Non-renal elimination of cystatin C may contribute to the result. The correlation between reciprocal cystatin C and GFR suggested its superiority in predicting GFR compared to creatinine in subjects with normal and mildly reduced GFR.
    Clinical and Experimental Nephrology 08/2011; 15(6):868-76. · 1.37 Impact Factor
  • Article: Continuous positive airway pressure intolerance associated with elevated nasal resistance is possible mechanism of complex sleep apnea syndrome.
    [show abstract] [hide abstract]
    ABSTRACT: Complex sleep apnea syndrome (CompSAS) is diagnosed after an elimination of obstructive events with continuous positive airway pressure (CPAP), when a central apnea index ≥5/h or Cheyne-Stokes respiration pattern emerges in patients with obstructive sleep apnea syndrome (OSAS). However, the pathophysiology of CompSAS remains controversial. Of the 281 patients with suspected OSAS, all of whom underwent polysomnography conducted at Nagoya University Hospital, we enrolled 52 patients with apnea-hypopnea index ≥15/h (age 51.4 ± 13.3 years). The polysomnographic findings, left ventricular ejection fraction (LVEF), and nasal resistance were compared between the CompSAS patients and OSAS patients. Forty-three patients were diagnosed with OSAS and nine patients with central sleep apnea syndrome by natural sleep PSG. Furthermore, 43 OSAS patients were classified into the OSAS patients (OSAS group, n = 38) and the CompSAS patients (CompSAS group, n = 5) by the night on CPAP PSG. The nasal resistance was significantly higher in CompSAS group than in OSAS group (0.30 ± 0.10 vs. 0.19 ± 0.07 Pa/cm(3)/s, P = 0.004). The arousal index, percentage of stage 1 sleep, and oxygen desaturation index were significantly decreased, and the percentage of stage REM sleep was significantly increased in the OSAS group with the initial CPAP treatment, but not in the CompSAS group. In addition, the patients with CompSAS showed normal LVEF. CPAP intolerance secondary to an elevated nasal resistance might relate to frequent arousals, which could presumably contribute to an increase in central sleep apnea. Further evaluation in a large study is needed to clarify the mechanism of CompSAS.
    Sleep And Breathing 08/2011; 16(3):747-52. · 1.84 Impact Factor
  • Article: Evaluation of GFR measurement method as an explanation for differences among GFR estimation equations.
    American Journal of Kidney Diseases 06/2011; 58(3):496-8. · 5.43 Impact Factor
  • Article: Nup358, a nucleoporin, functions as a key determinant of the nuclear pore complex structure remodeling during skeletal myogenesis.
    [show abstract] [hide abstract]
    ABSTRACT: The nuclear pore complex (NPC) is the only gateway for molecular trafficking across the nuclear envelope. The NPC is not merely a static nuclear-cytoplasmic transport gate; the functional analysis of nucleoporins has revealed dynamic features of the NPC in various cellular functions, such as mitotic spindle formation and protein modification. However, it is not known whether the NPC undergoes dynamic changes during biological processes such as cell differentiation. In the present study, we evaluate changes in the expression levels of several nucleoporins and show that the amount of Nup358/RanBP2 within individual NPCs increases during muscle differentiation in C2C12 cells. Using atomic force microscopy, we demonstrate structural differences between the cytoplasmic surfaces of myoblast and myotube NPCs and a correlation between the copy number of Nup358 and the NPC structure. Furthermore, small interfering RNA-mediated depletion of Nup358 in myoblasts suppresses myotube formation without affecting cell viability, suggesting that NUP358 plays a role in myogenesis. These findings indicate that the NPC undergoes dynamic remodeling during muscle cell differentiation and that Nup358 is prominently involved in the remodeling process.
    FEBS Journal 02/2011; 278(4):610-21. · 3.79 Impact Factor

Institutions

  • 2013
    • Chubu University
      Nagoya-shi, Aichi-ken, Japan
  • 2007–2012
    • Osaka City University
      • Department of Nephrology
      Ōsaka-shi, Osaka-fu, Japan
  • 2004–2012
    • Nagoya University
      • • Division of Nephrology
      • • Department of Preventive Medicine
      • • Division of Cardiology
      • • Graduate School of Medicine
      Nagoya-shi, Aichi-ken, Japan
  • 2004–2011
    • Osaka University
      • • Graduate School of Frontier Biosciences
      • • Biochemistry
      Ōsaka-shi, Osaka-fu, Japan
  • 2010
    • The University of Tokyo
      • College of Art and Science & Graduate School of Arts and Sciences
      Tokyo, Tokyo-to, Japan
  • 2006
    • Ludwig-Maximilian-University of Munich
      • Department of Internal Medicine I
      München, Bavaria, Germany