The prevalence and prognostic value of anemia in male and female patients with chronic systolic heart failure / 中国医师杂志

Objective To investigate the prevalence and prognostic value of anemia in male and female patients with chronic systolic heart failure (CSHF).Methods Data of in-hospital patients with CSHF were investigated between 2000 and 2010 from 12 hospitals in Hubei Province.Patients were divided into normal hemoglobin (Hb) group,mild anemia group,moderate anemia group,severe and extreme anemia group.According to age,body mass index (BMI) and correction of glomerular filtration rate (GFRc),patients were divided into several subgroups,respectively.Multivariate logistic regression was performed to determinate the associated factors with anemia.Kaplan-Meier curve was performed to evaluate the difference in all-cause mortality in male and female patients with anemia.Univariate and multivariate Cox proportion hazard analysis was performed to determinate the risk of all-cause mortality among different anemia group in male and female patients.Results A total of 16681 patients were enrolled.Anemia accounted for 23.79％ and 27.29％,separately,in male and female patients with CSHF.BMI and GFRc were related to anemia in both male and female patients with CSHF,while only age was related to anemia for female patients with CSHF.The hazard ratio of all-cause mortality was 1.08 (P ＜ 0.01),1.13 (P ＜ 0.O1) and 1.02 (P =0.74),respectively,for all,male and female anemia patients with CSHF,compared to normal Hb group.Compared to normal Hb group,the hazard ratio of mild anemia group,moderate anemia group,severe and extreme anemia group was 1.05 (P =0.14),1.20 (P ＜0.01) and 1.36 (P ＜0.01),respectively,for all CSHF patients;1.11 (P ＜ 0.01),1.35 (P ＜ 0.01) and 1.37 (P ＜ 0.01),respectively,for male;0.96 (P=0.48),1.08 (P=0.40) and3.47 (P＜0.01),respectively,for female.Conclusions Compared to male,female patients suffer higher prevalence of anemia in patients with CSHF.There is a significant difference in risk factors and prognosis of anemia between male and female patients with CSHF.

Efectos beneficiosos de la simpatectomía renal sobre el remodelado vascular pulmonar en la hipertensión arterial primaria experimental / Beneficial effects of renal denervation on pulmonary vascular remodeling in experimental pulmonary artery hypertension

Introducción y objetivos. La activación tanto del sistema nervioso simpático como del sistema renina-angiotensina-aldosterona está estrechamente relacionada con la hipertensión arterial pulmonar. Nuestra hipótesis era que la simpatectomía renal reduce la actividad del sistema renina-angiotensina-aldosterona e inhibe la progresión de la hipertensión arterial pulmonar. Métodos. Se asignó aleatoriamente a un total de 22 perros beagle a tres grupos de estudio. Se efectuaron determinaciones de la dinámica pulmonar de esos animales antes y 8 semanas después de la inyección de 0,1 ml/kg de dimetilformamida (perros de control) o de 2 mg/kg de deshidromonocrotalina (perros con hipertensión arterial pulmonar y perros con hipertensión arterial pulmonar + simpatectomía renal). Ocho semanas después de la inyección, se determinaron las concentraciones de neurohormonas y se evaluó la morfología del tejido pulmonar. Resultados. Se observó un aumento significativo de la concentración de angiotensina II y endotelina-1 en plasma después de 8 semanas en los perros con hipertensión arterial pulmonar, y los valores obtenidos en los tejidos pulmonares de estos animales eran superiores a los de los perros del grupo de control y el grupo de simpatectomía renal (medias: angiotensina II, 65 ± 9,8 frente a 38 ± 6,7 y 46 ± 8,1; endotelina-1, 96 ± 10,3 frente a 54 ± 6,2 y 67 ± 9,4; p < 0,01). La deshidromonocrotalina aumentó la presión arterial pulmonar media (16 ± 3,4 frente a 33 ± 7,3 mmHg; p < 0,01), y la simpatectomía renal evitó que se produjera este aumento. La proliferación celular del músculo liso pulmonar fue mayor en los perros con hipertensión arterial pulmonar que en los animales de los grupos de control y de hipertensión arterial pulmonar + simpatectomía renal. Conclusiones. La simpatectomía renal atenúa el remodelado vascular pulmonar y reduce la presión arterial pulmonar en la hipertensión arterial pulmonar experimental. El efecto de la simpatectomía renal puede contribuir a reducir las concentraciones de neurohormonas (AU)

Introduction and objectives. Activation of both the sympathetic nervous system and the renin-angiotensin-aldosterone system is closely associated with pulmonary arterial hypertension. We hypothesized that renal denervation decreases renin-angiotensin-aldosterone activity and inhibits the progression of pulmonary arterial hypertension. Methods. Twenty-two beagles were randomized into 3 groups. The dogs’ pulmonary dynamics were measured before and 8 weeks after injection of 0.1 mL/kg dimethylformamide (control dogs) or 2 mg/kg dehydromonocrotaline (pulmonary arterial hypertension and pulmonary arterial hypertension + renal denervation dogs). Eight weeks after injection, neurohormone levels and pulmonary tissue morphology were measured. Results. Levels of plasma angiotensin II and endothelin-1 were significantly increased after 8 weeks in the pulmonary arterial hypertension dogs and were higher in the lung tissues of these dogs than in those of the control and renal denervation dogs (mean [standard deviation] angiotensin II: 65 [9.8] vs 38 [6.7], 46 [8.1]; endothelin-1: 96 [10.3] vs 54 [6.2], 67 [9.4]; P < .01). Dehydromonocrotaline increased the mean pulmonary arterial pressure (16 [3.4] mmHg vs 33 [7.3] mmHg; P < .01), and renal denervation prevented this increase. Pulmonary smooth muscle cell proliferation was higher in the pulmonary arterial hypertension dogs than in the control and pulmonary arterial hypertension + renal denervation dogs (AU)

Beneficial Effects of Renal Denervation on Pulmonary Vascular Remodeling in Experimental Pulmonary Artery Hypertension.

INTRODUCTION AND OBJECTIVES: Activation of both the sympathetic nervous system and the renin-angiotensin-aldosterone system is closely associated with pulmonary arterial hypertension. We hypothesized that renal denervation decreases renin-angiotensin-aldosterone activity and inhibits the progression of pulmonary arterial hypertension. METHODS: Twenty-two beagles were randomized into 3 groups. The dogs' pulmonary dynamics were measured before and 8 weeks after injection of 0.1mL/kg dimethylformamide (control dogs) or 2mg/kg dehydromonocrotaline (pulmonary arterial hypertension and pulmonary arterial hypertension + renal denervation dogs). Eight weeks after injection, neurohormone levels and pulmonary tissue morphology were measured. RESULTS: Levels of plasma angiotensin II and endothelin-1 were significantly increased after 8 weeks in the pulmonary arterial hypertension dogs and were higher in the lung tissues of these dogs than in those of the control and renal denervation dogs (mean [standard deviation] angiotensin II: 65 [9.8] vs 38 [6.7], 46 [8.1]; endothelin-1: 96 [10.3] vs 54 [6.2], 67 [9.4]; P < .01). Dehydromonocrotaline increased the mean pulmonary arterial pressure (16 [3.4] mmHg vs 33 [7.3] mmHg; P < .01), and renal denervation prevented this increase. Pulmonary smooth muscle cell proliferation was higher in the pulmonary arterial hypertension dogs than in the control and pulmonary arterial hypertension + renal denervation dogs. CONCLUSIONS: Renal denervation attenuates pulmonary vascular remodeling and decreases pulmonary arterial pressure in experimental pulmonary arterial hypertension. The effect of renal denervation may contribute to decreased neurohormone levels.

Prognostic value of right ventricular end-diastolic diameter in patients with chronic systolic heart failure / 中华老年医学杂志

Objective To investigate the prognostic value of right ventricular end-diastolic diameter (RVDD) in patients with chronic systolic heart failure (CHF).Methods A retrospective study was conducted with clinical data of inpatients from 12 third-grade class-A hospitals of Hubei Province between 2000 to 2010,followed up by phone calls.Based on RVDD,patients diagnosed with chronic systolic CHF were divided into four groups:＞38 mm,31-38 mm,25-30 mm and ＜25 mm groups;based on prognosis,patients were divided into the death group and the survival group.Of the death group,patients were further divided into the heart failure death subgroup and the sudden cardiac death subgroup.Single-factor and multi-factor Cox survival analyses were conducted to analyze the relationships between RVDD and mortality,including all-cause mortality,CHF mortality and sudden cardiac death (SCD).Results A total of 16681 patients were enrolled in this study.They were followed up for 1-4 years,during which 6453 died.Multivariate Cox survival analysis showed that the mortality risk for patients with RVDD between 25-30 mm,between 31-38 mm,and ＞38 mm groups was 1.87,2.41,3.95 times that for patients with RVDD＜25 mm,respectively (95％CI:1.64-2.13,2.06-2.80,3.61-4.32,all P＜0.01).The risk of sudden cardiac death for patients with RVDD＞38mm was 3.82 times that for patients with RVDD＜25 mm (95％CI:2.27-5.94,P＜0.01).The areas under the ROC curve for death by the best prediction model alone and RVDD combined with the best respectively.RVDD increased the areas under the ROC curve for all cause mortality,CHF mortality and sudden cardiac death.The best prediction model combined with RVDD could discriminate between total mortality,heart failure mortality and sudden cardiac death for patients with different causes of death in multivariate analysis.Conclusions RVDD has a predictive value in the prognosis of patients with chronic systolic heart failure.RVDD increases the sensitivity and specificity of the best prediction model for total mortality prediction in patients with chronic systolic heart failure.RVDD increases the sensitivity and specificity of the best prediction model to discriminate between all-cause mortality,heart failure mortality and sudden cardiac death in patients with different causes of death.RVDD＞38 mm can serve as an indicator for the assessment of sudden cardiac death in CHF patients.

Effect of dl-3n-butylphthalide on sympathetic remodeling at infarct border zone in rats with myocardial infarction / 中华老年医学杂志

Objective To investigate the effect of dl-3n-Butylphthalide (NBP) on cardiac function and sympathetic remodeling in rats with myocardial infarction (MI).Methods Totally 50 male SD rats were randomly divided into 3 groups:Sham-operated (sham) group (n 10),myocardial infraction (MI) group (n=20) and MI with NBP group (n=20).A rat myocardial infarction model was established by ligating anterior descending branch of coronary artery.Rats in MI with NBP group were received the gavage treatment with NBP.Cardiac function was evaluated by hemodynamic detection at 7 day post-MI.Cardiac tissues were stained with hematoxylin and eosin as well as Masson trichrome.The distribution and density of growth associated protein-43-(GAP-43) and tyrosine hydroxytase-(TH) positive nerve at infarction border zone were detected by immunohistochemistry.The activation of nuclear factor-κB (NF-κB) signaling pathway was detected by western blot analysis.Results 8 rats died in MI group,in which 2 rats died within 24h.7 rats died in MI with NBP group,and in which 3 rats died within 24 h.The left ventricular end-diastolic pressure (LVEDP) and left ventricular end-systolic pressure (LVESP) were (7.81 ± 2.46) mmHg (1 mmHg=0.133 kPa) and (103.32±10.59) mmHg,(18.93±3.17) mmHg and (136.44±13.62) mmHg,(16.56±4.82) mmHg and (112.83±16.97) mmHg in sham group,MI group and MI with NBP group respectively.There were no significant differences in + dP/dt and-dP/dt between MI group and MI with NBP group (both P＞0.05).Compared with sham group,the collagen volume fraction at infarct border zone was increased in MI group (P＜0.05),but was reduced in MI with NBP group as compared to the MI group (P＜0.05).The densities of GAP-43-and TH-positive nerves at infarct border zone were increased in MI group as compared with sham group,and reduced in MI with NBP group as compared with MI group (both P＜0.05).NBP could reduced p IKBα protein expression and increase IKBα protein expression in rats with MI.Conclusions NBP may improve the sympathetic remodeling after MI via the inhibition of NF-κB signaling pathway.

Influence of Wenxin particle on cardiac electrophysiology in depressed rats after myocardial infarction / 心血管康复医学杂志

Objective: To investigate influence of Wenxin particle on cardiac electrophysiology in rats complicated with depression after myocardial infarction (MI). Methods: A total of 50 SD rats were randomly and equally divided into normal group, MI group, depression group, MI complicated with depression group (model group) and Wenxin particle group (Wenxin particle were given to model rats by gavage, 2 g/d, 28d). Model（MI complicated with depression）rats were made by acute ligation of left coronary artery and supply chronic unpredictable mild stress in order. The influences of Wenxin particle on cardiac electrophysiological indexes, such as monophasic action potential (MAP90), left ventricular effective refractory period (ERP) and ventricular fibrillation threshold (VFT) were evaluated in Wenxin particle group. Results: (1) Compared with normal group, there were significant decrease in behavior scores (P<0.05) in model group, after four-week treatment with Wenxin particle, their behavior scores significantly increased (P<0.01); (2) Compared with normal group, there were significant increase in MAPD90 and ERP, and significant decrease in VFT in model group (P<0.05); compared with model group, there were significant decrease in MAPD90 [(89.33±7.12) ms vs. (72.29±8.37) ms] and ERP [(84.00±6.57) ms vs. (68.00±7.43) ms], and significant increase in VFT [(7±3.11)V vs. (29±5.60)V] in Wenxin particle group, P<0.05. Conclusion: Wenxin particle can improve cardiac electrical remodeling in rats complicated with depression after myocardial infarction, including decrease monophasic action potential duration and effective refractory period, and raise ventricular fibrillation threshold.

Relationship between the detection of carotid plaque's micro flow signals by B-flow imaging and acute cerebral infarction / 中华全科医师杂志

Objective To detect the micro flow signals of carotid plaque by ultrasound B-flow imaging (BFI) and elucidate its relationship with acute cerebral infarction.Methods A total of 63 patients with carotid plaques were divided into 2 groups.acute cerebral infarction (ACI,n =48) and control (n =15).BFI was used to detect the micro flow signals of plaques and comparisons were made with the categorizing results of contrast enhanced ultrasound (CEU).The data were analyzed between two methods.Results The micro flow signals were detected in 15.7％ (22/140)patients in the ACI group vs.2.3％(1/44) in the control group.There were more signals in hypoechoic plaques.The detection percentage of micro flow in grade Ⅲ was significantly higher than that in grades Ⅰ and Ⅱ with CEU (P =0.005,P =0.027).No significant differences existed between grades Ⅲ and Ⅳ (P =1.000).Conclusion BFI can detect effectively the micro flow signals of carotid plaques and this characteristic is correlated with the symptoms of ACI.

Pulse wave velocity, ankle-brachial index and carotid intima-media thickness measurement in the assessment of vascular status in elderly patients with isolated systolic hypertension / 中华健康管理学杂志

Objective To evaluate the relation of circadian blood pressure rhythm with vascular status in elderly patients with isolated systolic hypertension.MethodsAnkle-brachial index (ABI),brachial-ankle pulse wave velocity (baPWV) and carotid intima-media thickness (IMT) were measured in 74 elderly patients with non-dipper hypertension (non-dipper group)、78 elderly patients with dipper hypertension ( dipper group),and 72 healthy controls ( control group).Results In comparison with the dipper group,baPWV and IMT of the non-dipper group were significantly increased [ baPWV (1801.61± 314.27) vs (1658.67±274.80) (cm/s)],P＜0.01; IMT:(0.96 ±0.22) vs (0.87 +0.19) (mm),(P＜0.05),while ABI of the non-dipper group was decreased (1.03 ±0.17 vs1.12 ±0.18,P＜0.01).Identification rate was significantly different among 3 groups when baPWV ＞1400 cm/s (x2 =12.57,P ＜0.01) or ABI ＜0.9 ( x2 =9.74,P ＜0.01).The detection of carotid plaques was also significantly different ( x2 =16.49,P ＜ 0.01).Conclusions These findings suggest that vascular damage could be found in elderly patients with isolated systolic hypertension,especially in those with non-dipper hypertension.ABI,baPWV and IMT measurement may be helpful for the assessment of vascular status.

Study of periphery artery and renal injury in elderly patients with dipper and non-dipper isolated systolic hypertension / 中华老年医学杂志

Objective To evaluate periphery artery and renal injury in elderly patients with dipper and non-dipper isolated systolic hypertension(ISH). Methods Totally 187 elderly cases were divided into 51 patients with non-dipper hypertension,70 patients with dipper hypertension aged (72.4±5.6) years and 66 cases with normal blood pressure as control according to results of dynamic blood pressure recorder. Ankle-brachial index (ABI),brachial ankle artery pulse wave velocity (baPWV),retinol-binding protein (RBP) and Cystatin C were assessed. ABI and baPWV were determined by a non-invasive automatic waveform analyzer. Results The baPWV value in nondipper group was higher than dipper group [(1869.3±285.6)cm/s vs.(1703.1±235.2)cm/s,q=4.73,P＜0.01],while the value of ABI in non-dipper group was lower than dipper group (1.0 ±0.2vs.1.1±0.2,q=4.74,P＜0.01).The level of Cystatin C was elevated in non-dipper group versus dipper group [(1.4±0.5) mg/L vs. (1.0±0.5)mg/L,q=6.92,P＜0.01]. There were no differences in RBP concentration among the three groups (F=2.39,P＞0.05).At baPWV＞ 1400cm/s,the level of Cystatin C was increased in 47 cases with non-dipper hypertension as compared with 64 cases with dipper hypertension [(1.4±0.5)mg/L vs.(1.1±0.5)mg/L,q=5.59,P＜0.01].Conclusions The elderly patients with non-dipper hypertension may be more easily suffered from periphery artery and renal injury in comparison with dipper hypertension.

Effect of losartan on ventricular arrhythmia in elderly patients with hypertension / 中华老年医学杂志

ObjectiveTo evaluate the effect of losartan on ventricular arrhythmia in elderly patients with hypertension.Methods The 78 hypertension subjects with ventricular arrhythmia aged 65 to 89 years were randomly assigned to treatment with losartan or placebo (enalapril) for 12 months. The blood pressure, left ventricular mass index and ventricular arrhythmia were observed and analyzed.ResultsAfter 12 months treatment, the pressure lowering effect was similar in losartan versus enalapril groups, there were no differences in systolic pressure decrement and diastolic pressure decrement between the two groups (P＞0. 05). Left ventricular mass index was lower in enalapril groupthaninlosartangroup [(109.2±15. 4) g · m-2 vs. (128.5±16. 7) g · m-2, t=2.015, P＜0. 05].However, the prevalence of ventricular arrhythmia was lower in losartan group than in enalapril group [(628. 5±176.8)/24 h vs. (852.9±215.7)/24 h, t=2.417,P＜0.05]. No Pearson's correlations of reduction of ventricular arrhythmia with reduction of blood pressure (systolic: r=0. 094, P＞0. 05; diastolic: r= 0.08, P＞0. 05) and reduction of left ventricular mass index were found. in losartan group.Conclusions Initiation of antihypertensive treatment with losartan in elderly subjects appears to cause more reduction of ventricular arrhythmia than with enalapril, despite similar reduction of blood pressure.

Role of a disintegrin and metalloprotease with thrombospondin type 1 motifs in aged rat myocardium after ischemic preconditioning / 中华老年医学杂志

Objective To investigate the effect of ischemic preconditioning (IPC) on the expression of a disintegrin and metalloprotease with thrombospondin type 1 motifs (ADAMTS-1), and to study whether the application of small interfering (si)RNA specifically targeting ADAMTS-1 would help to recover IPC protection in the aged heart. Methods The 32 young (4 months) and 32 aged(24 months) male Sprague-Dawley (SD) rats were assigned randomly to IPC group (n=20) and sham operated group (n= 12) respectively. Myocardial samples from the ischemic-reperfused region were harvested for detecting the ADAMTS-1 expression. In addition, the 110 aged SD rats were assignedrandomly to ADAMTS-1 siRNA group and control group (n=55, each). The effects of ADAMTS-1siRNA transfcction on the expression of ADAMTS-1 protein, myocardial infarction survival rate,heart function and myocardial infarction size after IPC were observed.Results Twenty-four hours after IPC, the ADAMTS-1 protein expression increased significantly in iscbemic-reperfused region both in young and aged rats (P＜0. 05), and the protein expression was higher in aged rats than in young rats (P＜0.05). In young-IPC group, the absorbency showed ADAMTS-1 protein expression at 0 hrs and 24 hrs after IPC were 0. 05±0.01 and 0.12±0.03 by immunohistochemical staining, and were 0.68±0. 16 and 1. 17±0.21 by Western blots respectively. In aged-IPC group, the absorbency showed ADAMTS-1 protein expression at 0 hrs and 24 hrs after IPC were 0.07±0. 03 and 0.21 ±0.04 by immunohistochemical staining, and were 0. 76±0. 21 and 1. 48±0. 17 by Western blots. In the aged rats, ADAMTS-1 siRNA transfection inhibited ADAMTS-1 protein expression (0. 66±0. 19and 0.78±0.21, by Western blots at 0 hrs and 24 hrs after IPC, P＞0.05), but didn't improve myocardial infarction survival rates [ADAMTS-1 siRNA group and sham operated group: 14.3% (5/35) vs. 17.1 %(6/35), P＞0.05], left ventricular fractional shortening [(14.0±3.2)% vs. (13.0±2.9)%, P＞0.05] and myocardial infarction size[(39.0±4.1)% vs. (38.0±5.3)%, P＞0.05].Conclusions ADAMTS-1 expression induced by IPC increases significantly in aged versus in young rats. ADAMTS-1 knockdown by siRNA inhibits ADAMTS-1 protein expression but cannot recover the age-associated loss of IPC protection.

Impact of hematocrit on prognosis of patients with acute myocardial infarction / 中国综合临床

Objective To examine the relationship between hematocrit and risk of long term mortality among patients with acute myocardial infarction. Methods A total of 274 patients with acute myocardial infarction were recruited and divided into two groups by death after long term follow-up, the relationship between hematocrit and mortality was evaluated through the methods of independent t-test,chi-square test and multivariate regression analysis. Results The mean age was 69. 79 ± 7.45 years, with 73. 0% of male. The average of followup was 44. 4± 10. 7 months, with mortality of 38.7% . Comparison of baseline data showed that NYHA classification, smoking history, hemoglobin, hematocrit, mean red cell volume, glomerular filtration rate, ejection fraction,left ventricular diastolic diameter and right ventricular diameter was significantly different between the two groups( Ps ＜ 0. 05), Multivariable logistic analysis showed that hematocrit ,glomerular filtration rate, ejection fraction and smoking history were independently predicted factors, with OR of 0. 904 (95% CI: 0. 832 - 0. 982,P =0. 016) ,0. 983 (95% CI: 0. 969 -0. 996,P =0. 014) ,0. 932 (95% CI: 0. 887 -0. 979,P =0. 005) and 3. 230 (95% CI: 1.468 - 7. 106, P = 0. 004), respectively. The power of hematocrit to predict mortality was examined by ROC curves, the area under the curve was 0. 669(P ＜ 0. 001,95% CI: 0. 603 - 0. 736) Conclusion Hematocrit is a significant independent predictor for long term death among patients with acute myocardial infarction.

Effect of right ventricular end-diastolic diameter on prognosis of patients with chronic heart failure / 中国综合临床

Objective To determine the prognostic value of fight ventricular end-diastollc diameter (RVDD)in patients with chronic heart failure(CHF).Methods The clinical data of the in-hospital patients diagnosed as CHF were analyzed retrospectively.Telephone follow-up was carried out for all participants.The patients were divided into the survival group and death groups according to their clinical outcomes.The relationship between RVDD and death was evaluated by independent t-test and multivariate Logistic regression analysis.Results 1552 in-hospital patients were enrolled into the study.The mean age was 64.62 ± 10.45 years old,with 879(56.64％)male.After 3 years' follow-up,439(28.29％)patients died.Comparison of baseline data showed that gender,age,SBP,NYHA classification,the serum level of creatinine,LVEF,LVDD and RVDD were significantly different between the two groups(P ＜ 0.01);Multivariable logistic analysis showed that RVDD(OR=1.11,95％ CI:1.07-1.14,P ＜0.01),age(OR =1.03,95％ CI:1.02-1.05,P ＜0.01),creatinine(OR =1.02,95 ％ CI:1.01-1.04,P ＜ 0.01),LVEF(OR =0.93,95 ％ CI:0.92-0.97,P ＜ 0.01),LVDD(OR =1.13,95％ CI:1.09-1.17,P ＜0.01)and NYHA classification(OR =1.17,95％ CI:1.12-1.24,P ＜ 0.01)were independent predicting factors for the death of CHF patients.The power of RVDD to predict mortality was examined by ROC curves.The area under the curve was 0.805(95％ CI:0.798-0.812,P ＜ 0.01).Conclusion RVDD increases the risk of death in patients with CHF.RVDD is a significant independent predictor for death among patients with CHF.

Expression of retinol-binding protein 4 and phosphatidylinositol 3 kinase in insulin resistant rats and the role of pioglitazone intervention / 中华老年医学杂志

Objective To observe the expression of retinol-binding protein 4 (RBP4) and phosphatidylinositol 3 kinase (PI3K) in insulin resistant (IR) rats and the role of pioglitazone intervention. MethodsThirty-five male Wistar rats in SPF level were randomly divided into control fed with normal diet (n= 11 ) and IR model fed with high fat sucrose diet (HFSD) (n= 24). The IR rats were then randomly divided into two subgroups, namely IR fed with HFSD(n = 12) and pioglitazone intervention (n= 12) given a daily dose of 20 mg · kg 1 · d-1 pioglitazone and HFSD (IR +Pio group )for 8 weeks.All rats were killed after 16 weeks and the levels of serum TG, high density lipoprotein (HDL-C), low density lipoprotein (LDL-C), fasting blood-glucose (FBG), fasting serum insulin (FIns) and insulin resistance index (HOME-1R) were measured.Enzyme-linked immunosorbent assay (ELISA) and RT-PCR were employed to detect the level of serum RBP4 and the mRNA expression of RBP4 in the epididymis adipose tissues, respectively. Immunohistochemistry was used to detect the protein expression of PI3K in skeletal muscles while UV spectrophotometer was employed to measure level of serum AOPP. The ratio of visceral fat weight of mesentery, epididymis and peritoneum in abdominal cavity to body weight (BW) was calculated. Results(1) the level of BW, TG, LDL-C, FINS and the ratio of visceral fat weight to BW were higher in IR group than in control group, but HDL-C decreased significantly. After the intervention of pioglitazone, the level of BW,TG, LDL-C, FINS, and the ratio of visceral fat weight to BW in IR+Pio group were lower and HDL-C increased significantly than those in IR group.(2) The level of RBP4 from serum and epididymis adipose and serum AOPP were higher in IR group than in control and lower significantly in IR+Pio group than in IR group (all P＜0.05). (3) The expression of PI3K in skeletal muscles were lower in IR group than in NC group, and increased after the invention of pioglitazone. (4) FIns, the ratio of visceral fat weight to BW and LDL-C were positively correlated with RBP4 while HDL-C and PI3K negatively correlated with RBP4. Conclusions(1) The increased RBP4 can lead to metabolic disturbances and oxidative stress in IR rats.(2) RBP4 may decrease the insulin sensibility by weakening insulin signal transduction. (3) Pioglitazone can ameliorate insulin resistance by decreasing the level of RBP4 and serum AOPP and increasing the level of PI3K in skeletal muscles of IR rats.

Digitalis does not improve left atrial mechanical dysfunction after successful electrical cardioversion of chronic atrial fibrillation.

This study was designed to investigate whether administration of digitalis could improve mechanical function of left atrial appendage (LAA) and left atrium prospectively in patients with atrial stunning. Fifty-four consecutive patients in whom atrial stunning was observed immediately after cardioversion of chronic atrial fibrillation (AF) were randomized into digitalis or control group for 1 week following cardioversion. Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) were performed prior to, immediately following, 1 day after and 1 week after cardioversion to measure transmitral flow velocity and LAA flow velocity. Electrical cardioversion of AF elicited significantly slower left atrial appendage peak emptying velocity (LAA-PEV) and peak filling velocity (LAA-PFV) immediately following cardioversion in both groups. 1 day post cardioversion, there were no significant differences in transmitral E wave, A wave, E/A ratio, LAA-PEV, LAA-PFV or left atrial appendage ejection fraction (LAA-EF) between digitalis and control groups. 1 week post cardioversion, no significant differences were found in transmitral E wave, A wave, E/A ratio, LAA-PEV, LAA-PFV or LAA-EF between the two groups. The occurrence rates of spontaneous echo contrast were not significantly different between digitalis and control groups one day and one week post cardioversion. In conclusion, digitalis did not improve left atrial and appendage mechanical dysfunction following cardioversion of chronic AF. Digitalis did not prevent the development of spontaneous echo contrast in left atrial chamber and appendage. This may be due to the fact that digitalis aggravates intracellular calcium overload induced by chronic AF and has a negative effect on ventricular rate.

Molecular basis for losartan regulating transient outward potassium current / 中华老年医学杂志

Objective To investigate the molecular basis for anti-ventricular arrhythmic effects by losartan through measuring alteration in mRNA and protein levels of key K+ α channel-and-β subunits (Kv4.2,Kv4.3 and KChIP2) in ventricular myocytes in spontaneously hypertensive rats (SHRs).Methods SHRs were randomly assigned to losartan[10mg·kg-1·d-1,n=12] or placebo (n= 12) with age-and weight-matched WKY rats (n = 12) as control.After 8 weeks of treatment,cardiomyocytes were isolated by enzymolysis.Action potential of cardiomyocytes Ito was recorded,mRNA and protein levels of Kv4.2,Kv4.3 and KChIP2 were assessed by reverse transcriptase polymerase chain reaction and Western blot.Results The action potential duration (APD) measured at 50% and 90% repolarization was shorter in losartan group [(16.82 ± 3.79) ms and (68.49±13.25) ms] than in SHR control group [(24.56±4.59) ms and (73.26±15.47) ms,all P<0.01].Losartan increased Ito current density associated with significant increases in the mean levels of mRNA and protein of Kv4.2 and Ky4.3,and with significant decreases in the mean levels of mRNA and protein of KChIP2 compared with those in placebo SHR (all P<0.01).Conclusions Chronic blockade of AT1 receptors with losartan reverses cardiomyocytes electrical remodeling in SHR,resulting in the shortening of APD,which is associated with increasing Ito density by increasing mRNA and protein expression of Kv4.2,Kv4.3 and by decreasing mRNA and protein expression of KChIP2.

Effects of valsartan on L-type calcium current in ventricular myocytes of rabbits after myocardial infarction / 中华急诊医学杂志

Objective To determine the effects of valsartan, a specific angiotensin Ⅱ type 1 receptor blockade, on arrhythmia in rabbits after myocardial infarction and to discuss the mechanism. Method Twentyfour rabbits were randomly (random number) divided into sham operated (SO) group ( n = 8), myocardial infarction (MI) group ( n = 8) and valsartan (VAL) group ( n = 8). The rabbits of SO group were operated upon with median stemotomy without left ventricular coronary artery hgature. The rabbits of MI group and VAL group had median stemotomy with left ventricular coronary artery ligature. After MI, the rabbits of VAL group were fed with border zone of infracted left ventricular wall and the L-type calcium current was recorded by whole-cell patch clamp technique. Results Ventricular tachycardia or fibrillation (VT/VF) episodes were markedly decreased in VAL group than that in MI group [(3.2 ± 0. 6) vs. ( 11.7 ± 1.8)] after 12 weeks. The density of Ica-L current was higher in MI group than that in SO group and VAL group [( - 9.12 ± 0.73) pA/pF vs. ( - 6.29 ± 0.65) pA/pF and ( - 6.75 ± 0.64) pA/pF], ( P ＜ 0.05), however, there were no significant differences in Ica-L current between So group and VAL group ( P ＞ 0.05). Conclusions Valsartan reduces the VT/VF episodes in rabbits after MI. The effects of valsartan may be attributed to the inhibited electrical remodeling after MI.

Effects of exercises on expressions of retinol binding protein-4 in serum and phosphatidylinositol 3 kinase in skeletal muscles of insulin resistant rats / 中华物理医学与康复杂志

Objective To investigate the effects of exercises on expressions of retinol binding protein-4 (RBP4)in serum and phosphatidylinositol 3 kinase(PI3K)in skeletal muscles of insulin-resistant(IR)rats induced by diets.Methods A total of 30 Wistar rats were randomly divided into 3 groups:normal control group fed with normal diet,IR and exercises groups with high sugar and high fat diet.After 8 weeks,the Wistar rats in exercises group took swimming training for 6 weeks and all groups kept their assigned diets.At the end of 14-week experiment,the body weight(BW)of rats were measured,the general behaviors of rats were observed and then sacrificed.Rats' blood were sampled for measuring the levels of glucose(FPC)and serum RBP4,insulin(FINS),HDL-C,LDL-C,TG,TC.The indexes of IR(HOMA-IR)were calculated.The levels of RBP4 in serum were measured with ELISA technique.The ratios of visceral fat content to BW were calculated too.Immunohistochemistry method was applied to detect the expression levels of PI3K in skeletal muscle.Results(1)The levels of RBP4,TC,TG,FPG in serum in exercises group were lower than those in IR group significantly;the visceral fat content,ratio of visceral fat content to BW,FINS,RBP4,LDL and HOMA-IR in serum increased significantly in IR group after 6 weeks feeding compared with normal control group and exercises group(P＜0.01);the levels of HDL in serum in IR group were lower than those in the other two groups.(2)The expression levels of PI3K in skeletal muscles in exercises group were significantly higher than that in IR group(P＜0.01).(3)In a multiple stepwise regression analysis,FINS,ratio of visceral fat content to BW,LDL and HOMA-IR were correlated with RBP4 positively;HDL and PI3K were correlated with RBP4 negatively.Conclusion Exercises could downregulate the level of RBP4 in serum and upregulate the level of PI3K in skeletal muscles of IR rats.This effect was important for improving the organism sensibility to insulin.

Study on the effects of acidosis on transient receptor potential channel M7 (TRPM7) in mouse cardiac fibroblast / 中华老年医学杂志

Objective To investigate the effects of acidosis on the current change of transient receptor potential channel M7 (TRPM7) and collagen production in mouse cardiac fibroblast (MCFs), and to explore the pathophysiological function of TRPM7 on the cardiac fibrosis. Methods (1) The model of MCFs was established and isolated. (2) MCFs was subcuhured. (3) Patch clamp technique was used to observe the current characteristics of TRPM7 in low PH solutions. (4) The influence of acidic condition on Ca2+ influx in MCFs was recorded by calcium fluorescent indicators. Results (1) There was a high level expression of TRPM7 in MCFs and the electrophysiological characteristics of TRPM7-like (TRPM7L) was similar to that of TRPM7. (2) Ca2+ influx was increased in acidic condition, and the F340/F380 ratio was increased from 1.0 to 4. 6 at pH 4.0 compared with pH 7.0 (t=2.72, P<0.01). Conclusions (1) TRPM7 is the molecular basis of the native TRPM7L in MCFs and TRPM7L plays an important role in Ca2+ influx. (2) The pathophysiological function of MCFs is influenced by regulation of Ca2+ influx mediated by TRPM7L in the condition of acidosis.

Characteristic of the prevalence of J wave in apparently healthy Chinese adults.

BACKGROUND: The J wave has been seen in idiopathic ventricular fibrillation, Brugada syndrome, and early repolarization syndrome. Although these conditions share some ECG features, the clinical consequences are markedly different. J wave presentation in healthy subjects is not a rare phenomenon, although its characteristics are poorly understood. The aim of this study was to investigate the prevalence and the characteristics of the J wave in apparently healthy Chinese adults. METHODS: The study was comprised of 1817 consecutive healthy Chinese subjects undergoing annual routine medical examination from April 2006 to July 2006, including 1131 men and 686 women. Routine medical examination including ECG was performed. J wave was defined as a wave on the ECG that followed the QRS complex with amplitude of at least 0.05 mV for 0.03 sec. RESULTS: The prevalence of the J wave in all subjects was 7.26%. The prevalence of the J wave in males was significantly higher than in females (10.52 vs. 1.89%, p<0.01). The incidence of the J wave in the inferior leads (II, III, avF), right precordial leads (V1-V3), and left precordial leads (V4-V6) was 4.57, 0.50, and 2.20%, respectively. The J wave prevalence in the inferior leads was significantly higher than in the left and right precordial leads (both p<0.05). Moreover, the prevalence of the J wave had a positive correlation with age in all subjects (r=0.78, p<0.01). CONCLUSIONS: J wave presentation on the ECG of apparently healthy people is not a rare phenomenon and is more likely to be found in the elderly, in males, and more frequently occurs in the inferior leads than in left and right precordial leads.