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151.
Intracoronary infusion of autologous bone marrow cells and left ventricular function after acute myocardial infarction: a meta-analysis 总被引:3,自引:0,他引:3
Hristov M Heussen N Schober A Weber C 《Journal of cellular and molecular medicine》2006,10(3):727-733
Recent clinical studies have demonstrated that intracoronary infusion of autologous bone marrow cells (BMC) in conjunction with standard treatment may improve left ventricular function after an acute myocardial infarction (AMI). However, the results of these studies remain controversial, as the studies were relatively small in size and partially differed in design. We reviewed primary controlled randomized clinical studies comparing intracoronary transfer of autologous non-mobilized BMC combined with standard therapy versus standard therapy alone in patients with AMI. We identified five randomized controlled clinical trials, three of which were also placebo- and bone marrow aspiration-controlled. Non-mobilized BMC were infused into the revascularized coronary target artery 6.6 +/- 6.1 days after AMI. The mean follow- up period of 5.2 +/- 1.1 months was completed by 482 patients, 241 of which received infusion of BMC. The effect of BMC on left ventricular ejection fraction (LVEF) as a major functional parameter was evaluated. Analyzing the overall effect on the change in LVEF between baseline and follow-up value revealed a significant improvement in the BMCtreated group as compared to the control group (P = 0.04). Thus, considering the increase in LVEF during follow-up, transplantation of BMC may be a safe and beneficial procedure to support treatment of AMI. However, the functional improvement observed with this form of therapy was altogether relatively moderate and the studies were heterogeneous in design. Hence, further efforts aiming at large-scale, double-blind, randomized and placebo-controlled multi-center trials in conjunction with better definition of patients, which benefit from BMC infusion, appear to be warranted. 相似文献
152.
153.
Beatrice Brembilla-Perrot Pierre Yves Zinzius Laurent Groben Luc Freysz Lucian Muresan Jerome Schwartz Raphael P Martins Soumaya Jarmouni Ibrahim Nossier Nicolas Sadoul Hugues Blangy Arnaud Terrier De La Chaise Pierre Louis Olivier Selton Daniel Beurrier Jean Marc Sellal 《Indian pacing and electrophysiology journal》2010,10(4):162-172
Background
The results of programmed ventricular stimulation (PVS) may change after myocardial infarction (MI). The objective was to study the factors that could predict the results of a second PVS.Methods
Left ventricular ejection fraction (LVEF) and QRS duration were determined and PVS performed within 3 to 14 years of one another (mean 7.5±5) in 50 patients studied systematically between 1 and 3 months after acute MI.Results
QRS duration increased from 120±23 ms to 132±29 (p 0.04). LVEF did not decrease significantly (36±12 % vs 37±13 %). Ventricular tachycardia with cycle length (CL) > 220ms (VT) was induced in 11 patients at PVS 1, who had inducible VT with a CL > 220 ms (8) or < 220 ms (ventricular flutter, VFl) (3) at PVS 2. VFl or fibrillation (VF) was induced in 14 patients at PVS 1 and remained inducible in 5; 5 patients had inducible VT and 4 had a negative 2nd PVS. 2. 25 patients had initially negative PVS; 7 had secondarily inducible VT, 4 a VFl/VF, 14 a negative PVS. Changes of PVS were related to initially increasing QRS duration and secondarily changes in LVEF and revascularization but not to the number of extrastimuli required to induce VFl.Conclusions
In patients without induced VT at first study, changes of PVS are possible during the life. Patients with initially long QRS duration and those who developed decreased LVEF are more at risk to have inducible monomorphic VT at 2nd study, than other patients. 相似文献154.
155.
二维斑点追踪技术评价犬心梗后自体骨髓CD34+干细胞移植对心肌功能的影响 总被引:1,自引:0,他引:1
目的应用二维斑点追踪成像超声心动图(2D-STE),评价犬心梗后自体骨髓CD34+干细胞移植对心肌功能的影响。方法 12只杂种犬行冠脉左前降支结扎术,导致前壁心肌梗死,随机分为两组,A组为对照组,结扎术后两周二次开胸手术,经心肌注射磷酸盐缓冲液(PBS)1 mL;B组为治疗组,结扎术后两周二次开胸手术,经心肌注射含自体骨髓CD34+干细胞的磷酸盐缓冲液1 mL。应用STE对12只犬结扎术前、术后左室短轴基底段及心尖段心室节段径向应变(RS)、圆周方向应变(CS)以及局部心肌旋转(Rot)进行分析,并对对照组和治疗组治疗后的RS、CS及Rot变化进行比较。结果心肌梗死后梗死节段的RS、CS以及Rot均下降,治疗后治疗组梗死段RS及Rot较对照组好转。结论 STE能够评价左室短轴局部心肌的收缩功能,心肌梗死后梗死段短轴各方向应变减低,自体骨髓CD34+干细胞移植能够提高局部心肌的收缩功能。 相似文献
156.
The pathogenesis of heart disease has been associated with changes in the balance of certain trace elements. The aim of this
study was to evaluate the Zn, Fe, Cu, Cr, Ni, Pb, and Cd contents in scalp hair samples of myocardial infarction (MCI) patients
hospitalized in the cardiac ward of National Hospital in Hyderabad city (Pakistan). Scalp hair samples were collected from
193 patients (104 male, 89 female) of 3 age groups (46–60, 61–75, and 76–90 yr), for a comparative study, 200 normal, healthy
subjects (103 male, 97 female) of the same age groups residing in the same city were selected. All metals in scalp hair samples
were assessed by a flame/graphite furnace atomic absorption spectrophotometer, prior to microwave-assisted and conventional
wet acid digestion methods. Results were calculated in micrograms per gram.
The mean values of Fe and Zn of scalp hair samples of MCI patients were significantly reduced compared to the control subjects
of both genders. The mean Fe concentrations in male patients were 19.42, 12.36, and 6.98 vs 30.69, 24.42, and 16.75 for the
control patients in the three age groups (46–60, 61–75, and 76–90 yrs, respectively). The mean Zn concentration in male patients
were 169.2, 149.4, and 107.7 μg/g vs 206.1, 188.0, and 154.4 μg/g for the control group (p<0.002, 0.004, and 0.001) in all three age groups, respectively. These differences were also observed in the female study
groups. The mean values of Pb, Cd, and Ni were significantly high in patients compared to healthy subjects (mean Pb in male
patients: 11.85, 12.89, and 14.52 those of female patients were 11.88, 12.73, and 14.21 vs the male controls patients (6.08,
7.56, and 8.56) and female controls (5.99, 7.41, and 8.25) for all three age groups, respectively. The concentration of Ni
and Cd in the scalp hair samples of the heart patients of both sexes were significantly higher compared to the control; in
the case of Ni the range of significant difference for males was found to be p<0.001–0.009 and for females to be p<0.0.002–0.007 and significantly high concentration of Cd were observed in hair samples of patients than in controls in the
range for males (p<0.001–0.009) and in females (p<0.001–0.011). The Zn/Cu and Zn/Cd ratios in the scalp hair (p<0.01) of the diseased groups were significantly lower than that of the healthy groups.
Deficiency of essential trace metals and high level of toxic metals might play a role in the development of heart disease
in the subjects of this study. Toxic metals might also cause diminished absorption of essential elements. 相似文献
157.
Yogeeta SK Gnanapragasam A Kumar SS Subhashini R Sathivel A Devaki T 《Molecular and cellular biochemistry》2006,283(1-2):139-146
Studies on the lipid peroxidation and antioxidant changes and their significance during myocardial injury have provided a
new insight into the pathogenesis of heart disease. The heart failure subsequent to myocardial infarction may be associated
with an antioxidant deficit as well as increased myocardial oxidative stress. The present study was designed to evaluate the
effect of the combination of ferulic acid and ascorbic acid on antioxidant defense system and lipid peroxidation against isoproterenol
(ISO)-induced myocardial infarction in rats. Induction of rats with isoproterenol (150 mg/kg body weight daily, i.p.) for
2 days resulted in a marked elevation in lipid peroxidation, serum marker enzymes (LDH, CPK, GOT, and GPT), and a significant
decrease in activities of endogenous antioxidants (SOD, GPx, GST, CAT, and GSH). Pre-co-treatment with the combination of
ferulic acid (20 mg/kg body weight/day) and ascorbic acid (80 mg/kg body weight/day) orally for 6 days, significantly attenuated
these changes when compared to the individual treatment groups. Histopathological observations were also in correlation with
the biochemical parameters. Thus, ferulic acid and ascorbic acid significantly counteracted the pronounced oxidative stress
effect of ISO by the inhibition of lipid peroxidation, restoration of antioxidant status, and myocardial marker enzymes levels.
In conclusion, these findings indicate the synergistic protective effect of ferulic acid and ascorbic acid on lipid peroxidation
and antioxidant defense system during ISO-induced myocardial infarction and associated oxidative stress in rats. 相似文献
158.
In the current study, the improved oral bioavailability of a synthetic astaxanthin derivative (CardaxTM; disodium disuccinate astaxanthin) was utilized to evaluate its potential effects as a cardioprotective agent after 7-day
subchronic oral administration as a feed supplement to Sprague-Dawley rats. Animals received one of two concentrations of
CardaxTM in feed (0.1 and 0.4%; ∼125 and 500 mg/kg/day, respectively) or control feed without drug for 7 days prior to the infarct
study carried out on day 8. Thirty minutes of occlusion of the left anterior descending (LAD) coronary artery was followed
by 2 h of reperfusion prior to sacrifice, a regimen which resulted in a mean infarct size (IS) as a percentage (%) of the
area at risk (AAR; IS/AAR,%) of 61 ± 1.8%. The AAR was quantified by Patent blue dye injection, and IS was determined by triphenyltetrazolium
chloride (TTC) staining. CardaxTM at 0.1 and 0.4% in feed for 7 days resulted in a significant mean reduction in IS/AAR,% to 45 ± 2.0% (26% salvage) and 39
± 1.5% (36% salvage), respectively. Myocardial levels of free astaxanthin achieved after 7-day supplementation at each of
the two concentrations (400 ± 65 nM and 1634 ± 90 nM, respectively) demonstrated excellent solid-tissue target organ loading
after oral supplementation. Parallel trends in reduction of plasma levels of multiple lipid peroxidation products with disodium
disuccinate astaxanthin supplementation were observed, consistent with the documented in vitro antioxidant mechanism of action. These results extend the potential utility of this compound for cardioprotection to the
elective human cardiovascular patient population, for which 7-day oral pre-treatment (as with statins) provides significant
reductions in induced periprocedural infarct size. 相似文献
159.
Using an ex vivo rat heart model of ischemia-reperfusion (I-R) injury, we examined the effect of pharmacological preconditioning by chronic treatment with emodin (EMD)/oleanolic acid (OA) at low dose (25 μ mol/kg/day × 15) and/or ischemic preconditioning (IPC) (4 cycles of 5 min ischemia followed by 5 min of reperfusion) on myocardial I-R injury. The results indicated that EMD/OA pretreatment, IPC, or their combinations (EMD+IPC and OA+IPC) protected against myocardial I-R injury, as assessed by lactate dehydrogenase leakage and contractile force recovery. The cardioprotection was associated with a differential enhancement in mitochondrial antioxidant components. The combined EMD/OA and IPC pretreatment produced cardioprotective action in a semi-additive manner. This suggested that EMD/OA pretreatment and IPC protected against myocardial I-R injury via a similar but not identical biochemical mechanism. 相似文献
160.