Clinical implication of crescentic lesions in immunoglobulin A nephropathy

Lee, Mi Jung,Kim, Seung Jun,Oh, Hyung Jung,Ko, Kwang Il,Koo, Hyang Mo,Kim, Chan Ho,Doh, Fa Mee,Yoo, Tae-Hyun,Kang, Shin-Wook,Choi, Kyu Hun,Lim, Beom Jin,Jeong, Hyeon Joo,Han, Seung Hyeok Oxford University Press 2014 Nephrology, dialysis, transplantation Vol.29 No.2

<P><B>Background</B></P><P>To date, there has been much controversy about the role of crescentic lesion as a significant prognostic factor in immunoglobulin A nephropathy (IgAN). This study evaluated whether crescentic lesions predict adverse renal outcomes in IgAN patients.</P><P><B>Methods</B></P><P>A total of 430 patients with biopsy-proven IgAN between January 2000 and December 2009 were included. Histological variables of the Oxford classification (Oxford-MEST) and the presence of crescents were assessed. The primary endpoint was a 50% decline in estimated glomerular filtration rate.</P><P><B>Results</B></P><P>Of the 430 patients, 81 (18.8%) had a crescentic lesion. During a mean follow-up of 61 months, the primary outcome occurred in 19 (23.5%) patients with crescents compared with 40 (11.5%) patients without crescents (P = 0.01). A Kaplan–Meier plot showed that the 10-year renal survival rate was significantly lower in patients with crescents than patients without crescents (P = 0.01). However, in a multivariable Cox analysis which included clinical factors and the Oxford-MEST, crescents were not significantly associated with an increased risk of developing the primary outcome [hazard ratio: 0.71, 95% confidence interval (CI) 0.36–1.41, P = 0.33]. Furthermore, adding crescents to the Oxford-MEST did not improve the discriminative ability for the prediction of renal outcomes [<I>c</I>-statistic: 0.86 (0.81–0.91) vs. 0.86 (0.80–0.91), P = 0.21].</P><P><B>Conclusion</B></P><P>Crescentic lesion was not an independent prognostic factor, suggesting that crescents have limited value in predicting renal outcomes of IgAN.</P>

Interdialytic Weight Gain and Cardiovascular Outcome in Incident Hemodialysis Patients

Lee, Mi Jung,Doh, Fa Mee,Kim, Chan Ho,Koo, Hyang Mo,Oh, Hyung Jung,Park, Jung Tak,Han, Seung Hyeok,Yoo, Tae-Hyun,Kim, Yong-Lim,Kim, Yon Su,Yang, Chul Woo,Kim, Nam-Ho,Kang, Shin-Wook S. Karger AG 2014 American journal of nephrology Vol.39 No.5

<P>Abstract</P><P><B><I>Background:</I></B> Interdialytic weight gain (IDWG) has been regarded as a surrogate of volume overload, but also as a marker of a better nutritional status in end-stage renal disease (ESRD) patients on hemodialysis (HD). This paradoxical meaning of IDWG requires further investigation, particularly in adverse cardiovascular outcomes. <B><I>Methods:</I></B> A prospective cohort of 1,013 incident HD patients from 36 HD centers of the Clinical Research Center for ESRD in Korea was included. Patients were categorized into five groups according to the IDWG%, a ratio of absolute IDWG to dry weight: <1.0, ≥4.0, and every 1.0 increment in between. Primary outcome was major adverse cardiac and cerebrovascular events (MACCE). <B><I>Results:</I></B> During a mean follow-up of 18.7 months, primary outcome was observed in 104 patients (10.3%). In multivariate analysis, compared to patients with IDWG% of 1.0-1.9 (reference group), the hazard ratios (HRs) for primary outcome in the IDWG% <1.0, 2.0-2.9, 3.0-3.9, and ≥4.0 groups were 1.10 [95% confidence interval (CI) 0.55-2.20, p = 0.80], 1.15 (95% CI 0.59-2.27, p = 0.68), 1.80 (95% CI 0.95-3.41, p = 0.07), and 1.93 (95% CI 1.02-3.64, p = 0.04), respectively. Furthermore, even when residual renal function and 24-hour urine volume were adjusted, IDWG% ≥4.0 remained as a significant predictor of primary outcome (HR 2.03, 95% CI 1.02-4.02, p = 0.04). <B><I>Conclusion:</I></B> Increased IDWG% is a significant independent predictor of MACCE in incident HD patients. It could be helpful to prevent excessive IDWG for improving clinical outcomes in incident HD patients.</P><P>© 2014 S. Karger AG, Basel</P>

Decreased Circulating Klotho Levels in Patients Undergoing Dialysis and Relationship to Oxidative Stress and Inflammation

Oh, Hyung Jung,Nam, Bo Young,Lee, Mi Jung,Kim, Chan Ho,Koo, Hyang Mo,Doh, Fa Mee,Han, Jae Hyun,Kim, Eun Jin,Han, Ji Suk,Park, Jung Tak,Yoo, Tae-Hyun,Kang, Shin-Wook,Han, Dae-Suk,Han, Seung Hyeok International Society for Peritoneal Dialysis 2015 Peritoneal dialysis international Vol.35 No.1

<P>♦ <I>Introduction:</I> It has been reported that klotho deficiency is associated with oxidative stress and inflammation in experimental kidney disease models. Patients with endstage renal disease (ESRD) are particularly characterized by increased oxidative stress and inflammation. However, little is known about the relationship between these features and klotho in patients with ESRD.</P><P>♦ <I>Methods:</I> We conducted a single-center, cross-sectional study of 78 patients receiving peritoneal dialysis (PD). Serum concentrations of klotho, high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and 8-isoprostane were measured by enzyme-linked immunosorbent assay. To define factors independently associated with klotho, we determined Spearman’s correlation coefficients for between co-variates and conducted multiple linear regression analyses.</P><P>♦ <I>Results:</I> Patients were classified by median concentration of klotho. In patients with klotho levels > 329.6 pg/mL, serum 8-isoprostane and IL-6 levels were significantly higher than in those with klotho levels < 329.6 pg/mL. In correlation analyses, log 8-isoprostane (γ = –0.310, <I>p</I> = 0.006) and log IL-6 (γ = –0.343, <I>p</I> = 0.002) were inversely correlated with log klotho. After adjustment for age, gender, mean arterial pressure, log intact parathyroid hormone, and log IL-6, log 8-isoprostane was independently associated with log klotho (β = –0.158, <I>p</I> = 0.040). However, the significant relationship between klotho and IL-6 was not seen in an adjusted model.</P><P>♦ <I>Conclusions:</I> This study showed that circulating klotho levels were significantly associated with 8-isoprostane levels in patients undergoing PD, suggesting a potential link between klotho deficiency and enhanced oxidative stress in ESRD patients.</P>

Thyroid Hormone Replacement Therapy Attenuates the Decline of Renal Function in Chronic Kidney Disease Patients with Subclinical Hypothyroidism

Shin, Dong Ho,Lee, Mi Jung,Lee, Hye Sun,Oh, Hyung Jung,Ko, Kwang Il,Kim, Chan Ho,Doh, Fa Mee,Koo, Hyang Mo,Kim, Hyoung Rae,Han, Jae Hyun,Park, Jung Tak,Han, Seung Hyeok,Yoo, Tae-Hyun,Kang, Shin-Wook Mary Ann Liebert 2013 Thyroid Vol.23 No.6

Preservation of renal function by thyroid hormone replacement therapy in chronic kidney disease patients with subclinical hypothyroidism.

Shin, Dong Ho,Lee, Mi Jung,Kim, Seung Jun,Oh, Hyung Jung,Kim, Hyoung Rae,Han, Jae Hyun,Koo, Hyang Mo,Doh, Fa Mee,Park, Jung Tak,Han, Seung Hyeok,Yoo, Tae-Hyun,Kang, Shin-Wook Issued for the Endocrine Society by the Williams W 2012 The Journal of clinical endocrinology & metabolism Vol.97 No.8

<P>Subclinical hypothyroidism is not a rare condition, but the use of thyroid hormone to treat subclinical hypothyroidism is an issue of debate.</P>

Increased Dialysate MCP-1 is Associated with Cardiovascular Mortality in Peritoneal Dialysis Patients: A Prospective Observational Study

Ko, Kwang Il,Park, Kyoung Sook,Lee, Mi Jung,Doh, Fa Mee,Kim, Chan Ho,Koo, Hyang Mo,Oh, Hyung Jung,Park, Jung Tak,Han, Seung Hyeok,Kang, Shin-Wook,Yoo, Tae-Hyun S. Karger AG 2014 American journal of nephrology Vol.40 No.4

<P>Abstract</P><P><B><I>Background:</I></B> The aim of this study was to investigate the association between the dialysate MCP-1 (dMCP-1) and systemic inflammatory and nutritional markers in peritoneal dialysis (PD) patients. In addition, we examined the prognostic value of dMCP-1 on all-cause or cardiovascular mortality in these patients. <B><I>Methods:</I></B> We prospectively followed 169 prevalent PD patients from April 1st 2008 to December 31st 2012. At baseline, dMCP-1 and serum biochemical parameters including high sensitivity CRP (hs-CRP) and albumin were checked. All-cause mortality and cause of death were evaluated during the follow-up period. Based on the median level of dMCP-1, patients were classified as either low or high dMCP-1 groups. <B><I>Results:</I></B> Mean age, hs-CRP, and D/Pcr ratio at 4 h were significantly higher, while serum albumin levels and %lean body mass (LBM) were significantly lower in the high dMCP-1 group. During the mean follow-up period of 47.7 months, all-cause mortality and cardiovascular mortality rate were significantly higher in the high dMCP-1 group (9.6 and 6.3 per 100 person-years, respectively) compared to the low dMCP-1 group (5.1 and 3.1 per 100 person-years, respectively; p = 0.021, 0.038). In multivariate Cox analysis, high dMCP-1 was a significant independent predictor of all-cause mortality (hazard ratio: 1.83, 95% confidence interval: 1.03-3.24, p = 0.039). <B><I>Conclusions:</I></B> dMCP-1 levels are closely correlated with nutritional and systemic inflammatory markers in PD patients. In addition, increased dMCP-1 is significantly associated with higher all-cause and cardiovascular mortality. These findings suggest that local peritoneal inflammation could contribute to poor clinical outcomes in PD patients.</P><P>© 2014 S. Karger AG, Basel</P>

SynRM Servo-Drive CVT Systems Using MRRHPNN Control with Mend ACO

Jung-Chu Ting,Der-Fa Chen 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

Compared with classical linear controllers, a nonlinear controller can result in better control performance for the nonlinear uncertainties of continuously variable transmission (CVT) systems that are driven by a synchronous reluctance motor (SynRM). Improved control performance can be seen in the nonlinear uncertainties behavior of CVT systems by using the proposed mingled revised recurrent Hermite polynomial neural network (MRRHPNN) control with mend ant colony optimization (ACO). The MRRHPNN control with mend ACO can carry out the overlooker control system, reformed recurrent Hermite polynomial neural network (RRHPNN) control with an adaptive law, and reimbursed control with an appraised law. Additionally, in accordance with the Lyapunov stability theorem, the adaptive law in the RRHPNN and the appraised law of the reimbursed control are established. Furthermore, to help improve convergence and to obtain better learning performance, the mend ACO is utilized for adjusting the two varied learning rates of the two parameters in the RRHPNN. Finally, comparative examples are illustrated by experimental results to confirm that the proposed control system can achieve better control performance.

Nonlinear Backstepping Control of SynRM Drive Systems Using Reformed Recurrent Hermite Polynomial Neural Networks with Adaptive Law and Error Estimated Law

Jung-Chu Ting,Der-Fa Chen 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

The synchronous reluctance motor (SynRM) servo-drive system has highly nonlinear uncertainties owing to a convex construction effect. It is difficult for the linear control method to achieve good performance for the SynRM drive system. The nonlinear backstepping control system using upper bound with switching function is proposed to inhibit uncertainty action for controlling the SynRM drive system. However, this method uses a large upper bound with a switching function, which results in a large chattering. In order to reduce this chattering, a nonlinear backstepping control system using an adaptive law is proposed to estimate the lumped uncertainty. Since this method uses an adaptive law, it cannot achiever satisfactory performance. Therefore, a nonlinear backstepping control system using a reformed recurrent Hermite polynomial neural network with an adaptive law and an error estimated law is proposed to estimate the lumped uncertainty and to compensate the estimated error in order to enhance the robustness of the SynRM drive system. Further, the reformed recurrent Hermite polynomial neural network with two learning rates is derived according to an increment type Lyapunov function to speed-up the parameter convergence. Finally, some experimental results and a comparative analysis are presented to verify that the proposed control system has better control performance for controlling SynRM drive systems.

Novel mingled reformed recurrent hermite polynomial neural network control system applied in continuously variable transmission system

Jung-Chu Ting,Der-Fa Chen 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.9

Compared with the classical linear controller, the nonlinear controller can result better control performance for the nonlinear uncertainties of the continuously variable transmission (CVT) system which is spurred by the synchronous reluctance motor (SynRM). The better control performance obtained by use of the proposed novel mingled reformed recurrent Hermite polynomial neural network (MRRHPNN) control system can be presented dynamic behavior for the nonlinear uncertainties of CVT system. The novel MRRHPNN control system can carry out overlooker control system, reformed recurrent Hermite polynomial neural network control (RRHPNN) with an adaptive law, and reimbursed control with an appraised law. Additionally, in accordance with the Lyapunov stability theorem, the adaptive law in the RRHPNN and the appraised law of the reimbursed control are established. Furthermore, two varied learning rates of two weights for the RRHPNN according to increment-type Lyapunov function are derived to help improving convergence. At last the obtained better control performances by use of the proposed control method are verified through the illustrated results by the comparative experimentations.

Nonlinear Backstepping Control of SynRM Drive Systems Using Reformed Recurrent Hermite Polynomial Neural Networks with Adaptive Law and Error Estimated Law

Ting, Jung-Chu,Chen, Der-Fa The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

The synchronous reluctance motor (SynRM) servo-drive system has highly nonlinear uncertainties owing to a convex construction effect. It is difficult for the linear control method to achieve good performance for the SynRM drive system. The nonlinear backstepping control system using upper bound with switching function is proposed to inhibit uncertainty action for controlling the SynRM drive system. However, this method uses a large upper bound with a switching function, which results in a large chattering. In order to reduce this chattering, a nonlinear backstepping control system using an adaptive law is proposed to estimate the lumped uncertainty. Since this method uses an adaptive law, it cannot achiever satisfactory performance. Therefore, a nonlinear backstepping control system using a reformed recurrent Hermite polynomial neural network with an adaptive law and an error estimated law is proposed to estimate the lumped uncertainty and to compensate the estimated error in order to enhance the robustness of the SynRM drive system. Further, the reformed recurrent Hermite polynomial neural network with two learning rates is derived according to an increment type Lyapunov function to speed-up the parameter convergence. Finally, some experimental results and a comparative analysis are presented to verify that the proposed control system has better control performance for controlling SynRM drive systems.