Objectives To observe the effect of β3-Adrenoceptor (AR) on ventricle fibrillation threshold (VFT) and effective refractory period (ERP) in rats with heart failure. Methods Rats were randomized into control gro...Objectives To observe the effect of β3-Adrenoceptor (AR) on ventricle fibrillation threshold (VFT) and effective refractory period (ERP) in rats with heart failure. Methods Rats were randomized into control group and heart failure group. The expression of β3-ARmRNA was detected with RTPCR; The VFT, ERP, LVESP,LVEDP, +dp/dtmax and -dp/dtmax was measured at the same time with administration of BRL37344 ( 2 nmol / kg, β3- AR agonist). Results ①Both the expression of β3-AR mRNA and the proportion increased in rats with heart failure in comparison with control rats (0.028 vs. 0.011 and 5.4% vs 1.2%, P 〈 0.05);② ERP was longer in rats with heart failure than control group (70.5±5.5 ms vs 59.5±6.4ms, P 〈 0.05) and there was no difference of ERP in rats with heart failure with administration of BRL37344 (73.0±4.8 ms vs 70.5± 5.5 ms, P 〉0.05); ③VFT was lower in rats with heart failure than control group(10.9±0.8 mv vs 30.5± 1.3 mv, P〈 0.05) and decreased obviously in rats with heart failure with administration of BRL37344 (7.1±0.6 mv vs 10.9±0.8 mv, P 〈 0.05) ; The decrease of VFT correlated with the effect on LVESP, +dp/ dtmax,-dp/dtmax of BRL37344 and the expression of β3-AR mRNA (correlation coefficient: 0.788, 0.708, 0.759, 0.787; P 〈 0.05). Conclusions The expression of β3-AR mRNA of left ventricle was obviously increased in rats with heart failure, and activation of β3-AR had no effect on ERP but could decreased VFT which correlated with the effect of β3-AR on LVESP, +dp/dtmax, -dp/dtmax and the expression of β3-AR mRNA.展开更多
Objectives To investigate the changes of β3-adrenoceptor (β3-AR) mRNA expression in the rats with chronic heart failure (CHF), and to explore the effect of β blockers (βBs) on β3 mRNA expression. Methods Thirty-f...Objectives To investigate the changes of β3-adrenoceptor (β3-AR) mRNA expression in the rats with chronic heart failure (CHF), and to explore the effect of β blockers (βBs) on β3 mRNA expression. Methods Thirty-four rats were randomly divided into Sham group (n = 10) and heart failure group (n = 24). Rat model was established by aortic constriction. The survival rats in heart failure group were divided into heart failure control group (HF group, n = 6), metoprolol group (MET group, n = 8) and carvedilol group (CAR group, n = 8) three months after operation. Metoprolol tartarte was started orally with 12 mg·kg-1·d-1, carvedilol with 6 mg·kg-1·d-1, isometric saline was started in HF group. After three months of drug therapy, measurement of hemodynamics, index of ventricular mass, the level of β3-AR mRNA expression were performed. Results Compared with Sham group, left ventricular end systolic pressure (LVESP), and the absolute values of maximal rate of rise and fall ( ± dp/dtmax) of left ventricular pressure were all significantly decreased (P < 0.01), left ventricular end diastolic pressure (LVEDP) was significantly increased in HF group (P < 0.01). The hemodynamic parameters were improved by βBs, and carvedilol was more effective than metoprolol (P < 0.01). The index of ventricular mass was higher in HF group than MET group, CAR group and Sham group (P < 0.01). βBs significantly decreased the index of left ventricular mass (LVMI), and Carvedilol was more effective than metoprolol (P < 0.01). The index of right ventricular mass (RVMI) did not change in MET group (P > 0.05), but significant decrease could be seen in CAR group (P < 0.01). The level of β3-AR expression in left ventricle was greater than that in right ventricle whether in the failing heart or in the non-failing heart. Compared with Sham group, the level of β3-AR mRNA expression was significantly increased in HF group (P < 0.01). The levels of β3-AR mRNA expression showed a remarkable decrease in CAR group(P < 0.01), but was not seen in MET group. Conclusions The β3-AR expression level remarkably increases in the rat’s left and right failing ventricles. Carvedilol is more effective on improving hemodynamics and attenuating ventricular remodeling than metoprolol in the rats with CHF. Carvedilol rather than metoprolol downregulates β3-AR expression in the rat’s failing ventricles. The beneficial effect of carvedilol in CHF maybe partly due to the downregulation of β3-AR expression in the failing heart.展开更多
背景:3D打印技术可根据患者实际病情和治疗需求设计构建模型、手术导板和个性化植入体或固定物,在创伤性骨折修复中展示了巨大的应用前景。目的:综述3D打印技术在创伤性骨折中的应用。方法:检索Web of science、PubMed和中国知网数据库2...背景:3D打印技术可根据患者实际病情和治疗需求设计构建模型、手术导板和个性化植入体或固定物,在创伤性骨折修复中展示了巨大的应用前景。目的:综述3D打印技术在创伤性骨折中的应用。方法:检索Web of science、PubMed和中国知网数据库2020-2024年发表的创伤骨科领域3D打印技术应用的相关文献,英文检索词为“traumatic fracture,3D printing technology,digital model,surgical guide”,中文检索词为“创伤性骨折,3D打印技术,数字模型,手术导板”,经筛选和分析,最终纳入60篇文献进行分析。结果与结论:①创伤性骨折是各种致伤因素导致的骨骼连续性中断和完整性破坏的骨折现象,以可靠方案提高复位愈合效果,已成为骨外科相关研究领域亟需解决的热点问题;②3D打印技术是以数字模型数据为基础的,运用粉末状金属或聚合物等可黏合成型材料以立体光刻、沉积建模和光聚合物喷射等形式制造满足需求三维实体的技术,在数字骨科生物医学领域应用广泛;③3D打印技术在疾病诊断、术前规划、重建骨折三维模型、定制骨科植入体、定制固定支具及假肢、手术导板制作和骨缺损修复等方面发挥了显著的优势,可根据患者实际病情和治疗需求设计构建模型、手术导板和个性化植入体或固定物,为创伤性骨折的治疗提供了新的思路。展开更多
文摘Objectives To observe the effect of β3-Adrenoceptor (AR) on ventricle fibrillation threshold (VFT) and effective refractory period (ERP) in rats with heart failure. Methods Rats were randomized into control group and heart failure group. The expression of β3-ARmRNA was detected with RTPCR; The VFT, ERP, LVESP,LVEDP, +dp/dtmax and -dp/dtmax was measured at the same time with administration of BRL37344 ( 2 nmol / kg, β3- AR agonist). Results ①Both the expression of β3-AR mRNA and the proportion increased in rats with heart failure in comparison with control rats (0.028 vs. 0.011 and 5.4% vs 1.2%, P 〈 0.05);② ERP was longer in rats with heart failure than control group (70.5±5.5 ms vs 59.5±6.4ms, P 〈 0.05) and there was no difference of ERP in rats with heart failure with administration of BRL37344 (73.0±4.8 ms vs 70.5± 5.5 ms, P 〉0.05); ③VFT was lower in rats with heart failure than control group(10.9±0.8 mv vs 30.5± 1.3 mv, P〈 0.05) and decreased obviously in rats with heart failure with administration of BRL37344 (7.1±0.6 mv vs 10.9±0.8 mv, P 〈 0.05) ; The decrease of VFT correlated with the effect on LVESP, +dp/ dtmax,-dp/dtmax of BRL37344 and the expression of β3-AR mRNA (correlation coefficient: 0.788, 0.708, 0.759, 0.787; P 〈 0.05). Conclusions The expression of β3-AR mRNA of left ventricle was obviously increased in rats with heart failure, and activation of β3-AR had no effect on ERP but could decreased VFT which correlated with the effect of β3-AR on LVESP, +dp/dtmax, -dp/dtmax and the expression of β3-AR mRNA.
文摘Objectives To investigate the changes of β3-adrenoceptor (β3-AR) mRNA expression in the rats with chronic heart failure (CHF), and to explore the effect of β blockers (βBs) on β3 mRNA expression. Methods Thirty-four rats were randomly divided into Sham group (n = 10) and heart failure group (n = 24). Rat model was established by aortic constriction. The survival rats in heart failure group were divided into heart failure control group (HF group, n = 6), metoprolol group (MET group, n = 8) and carvedilol group (CAR group, n = 8) three months after operation. Metoprolol tartarte was started orally with 12 mg·kg-1·d-1, carvedilol with 6 mg·kg-1·d-1, isometric saline was started in HF group. After three months of drug therapy, measurement of hemodynamics, index of ventricular mass, the level of β3-AR mRNA expression were performed. Results Compared with Sham group, left ventricular end systolic pressure (LVESP), and the absolute values of maximal rate of rise and fall ( ± dp/dtmax) of left ventricular pressure were all significantly decreased (P < 0.01), left ventricular end diastolic pressure (LVEDP) was significantly increased in HF group (P < 0.01). The hemodynamic parameters were improved by βBs, and carvedilol was more effective than metoprolol (P < 0.01). The index of ventricular mass was higher in HF group than MET group, CAR group and Sham group (P < 0.01). βBs significantly decreased the index of left ventricular mass (LVMI), and Carvedilol was more effective than metoprolol (P < 0.01). The index of right ventricular mass (RVMI) did not change in MET group (P > 0.05), but significant decrease could be seen in CAR group (P < 0.01). The level of β3-AR expression in left ventricle was greater than that in right ventricle whether in the failing heart or in the non-failing heart. Compared with Sham group, the level of β3-AR mRNA expression was significantly increased in HF group (P < 0.01). The levels of β3-AR mRNA expression showed a remarkable decrease in CAR group(P < 0.01), but was not seen in MET group. Conclusions The β3-AR expression level remarkably increases in the rat’s left and right failing ventricles. Carvedilol is more effective on improving hemodynamics and attenuating ventricular remodeling than metoprolol in the rats with CHF. Carvedilol rather than metoprolol downregulates β3-AR expression in the rat’s failing ventricles. The beneficial effect of carvedilol in CHF maybe partly due to the downregulation of β3-AR expression in the failing heart.