This paper deals with the problem of stability for systems with delay varying in an interval.A new Lyapunov functional,which makes use of the information of both the lower and upper bounds of the interval time-varying...This paper deals with the problem of stability for systems with delay varying in an interval.A new Lyapunov functional,which makes use of the information of both the lower and upper bounds of the interval time-varying delay,is proposed to derive some new stability criteria.Furthermore,the relationship of the time-varying delay and its lower bound and upper bound is taken into account.As a result,some less conservative delay-dependent stability criteria are obtained without ignoring any useful information in the derivative of Lyapunov functional,which are established in the forms of linear matrix inequalities.Numerical examples are provided to show that the obtained results are better than existing ones.展开更多
Renal tubulointerstitialfibrosis(TIF)is the common end stage of various chronic renal diseases,and pirfenidone(PFD)is a novel,broad-spectrum anti-fibrotic compound but little is known about its effect and mechanism of a...Renal tubulointerstitialfibrosis(TIF)is the common end stage of various chronic renal diseases,and pirfenidone(PFD)is a novel,broad-spectrum anti-fibrotic compound but little is known about its effect and mechanism of action on renal TIF.In this work,we employed a unilateral ureteral obstruction(UUO)rat model to investigate the apoptosis of renal tubular epithelial cells(RTC)after PFD treatment.Thirty-five Sprague Dawley(SD)rats were randomized into three groups:sham-operated group(n=7),UUO group(n=14)and PFD group(n=14).All rats were sacrificed at day 7 or 14 after operation.Renal histology was studied by using periodic acid schiff reagent(PAS)and Masson trichromic stain(MASSON);apoptosis was detected by in situ terminal deoxynucleotide transferase-mediated dUTP-biotin nick end-labeling(TUNEL)method;tubular caspase-3 expression was assessed by immunohistochemistry.The content of malondialdehyde(MDA)and total activity of superoxide dismutase(T-SOD)in the renal cortex were determined by chemical colorimetry method.TIF,apopto-sis of RTC,tubular expression of caspase-3 and the content of MDA were increased in the UUO group compared with those in the sham-operated group,and were ameliorated significantly by PFD treatment(P<0.05).The activity of SOD was decreased in the UUO group,but was increased by PFD treatment(P<0.05).Our results showed that PFD could ameliorate TIF in the UUO group,and the possible mechanism was by reducing the apoptosis of RTC,which involved oxidative stress and caspase-3.展开更多
基金supported by the National Natural Science Foundation of China (60874025)the Natural Science Foundation of Hunan Province(10JJ6098)the Scientific Research Fund of Hunan Provincial Education Department (10C0638)
文摘This paper deals with the problem of stability for systems with delay varying in an interval.A new Lyapunov functional,which makes use of the information of both the lower and upper bounds of the interval time-varying delay,is proposed to derive some new stability criteria.Furthermore,the relationship of the time-varying delay and its lower bound and upper bound is taken into account.As a result,some less conservative delay-dependent stability criteria are obtained without ignoring any useful information in the derivative of Lyapunov functional,which are established in the forms of linear matrix inequalities.Numerical examples are provided to show that the obtained results are better than existing ones.
文摘Renal tubulointerstitialfibrosis(TIF)is the common end stage of various chronic renal diseases,and pirfenidone(PFD)is a novel,broad-spectrum anti-fibrotic compound but little is known about its effect and mechanism of action on renal TIF.In this work,we employed a unilateral ureteral obstruction(UUO)rat model to investigate the apoptosis of renal tubular epithelial cells(RTC)after PFD treatment.Thirty-five Sprague Dawley(SD)rats were randomized into three groups:sham-operated group(n=7),UUO group(n=14)and PFD group(n=14).All rats were sacrificed at day 7 or 14 after operation.Renal histology was studied by using periodic acid schiff reagent(PAS)and Masson trichromic stain(MASSON);apoptosis was detected by in situ terminal deoxynucleotide transferase-mediated dUTP-biotin nick end-labeling(TUNEL)method;tubular caspase-3 expression was assessed by immunohistochemistry.The content of malondialdehyde(MDA)and total activity of superoxide dismutase(T-SOD)in the renal cortex were determined by chemical colorimetry method.TIF,apopto-sis of RTC,tubular expression of caspase-3 and the content of MDA were increased in the UUO group compared with those in the sham-operated group,and were ameliorated significantly by PFD treatment(P<0.05).The activity of SOD was decreased in the UUO group,but was increased by PFD treatment(P<0.05).Our results showed that PFD could ameliorate TIF in the UUO group,and the possible mechanism was by reducing the apoptosis of RTC,which involved oxidative stress and caspase-3.
