Tissue damage in acute myocardial infarction: selective protection by vitamin E

A growing amount of scientific evidence supports the participation of oxygen radicals in heart disease and, consequently, a protective effect of vitamin E (VE), beta-carotene (BC), and other antioxidants. The aim of this study was to correlate plasma VE and BC concentration with the clinical course of the acute myocardial infarction (AMI). We evaluated 120 patients that were admitted at the coronary units within 12 h after the development of AMI symptoms. The AMI was diagnosed by clinical and biochemical criteria and by electrocardiography and echocardiography. Plasma VE and BC concentration was determined by high performance liquid chromatography. The patients were separated according to the plasma concentration of VE (group H, VE > 17.5 microM; group L, VE < 17.5 microM). Clinical history of patients, age, sex, associated cardiovascular risk factors, AMI localization, hemodynamic class, and the treatment received were similar between different groups. The blood levels of creatine phosphokinase (CK) evaluated either 24- or 48-h after admittance, were higher in group L than in group H (24 h: H = 436 +/- 31 U/ml vs. L = 642 +/- 84 U/ml; p < .005; 48 h: H = 242 +/- 21 U/ml; L = 423 +/- 82 U/ml, p < 0.005). The number of deflexions in the electrocardiogram at admittance (ECG-D) was significantly higher in group L than in group H (4.7 +/- 0.3 vs. 3.7 +/- 0.2; p < .005). The number of new Q waves in the ECG of release (ECG-Q) was higher in group L than in group H (2.9 +/- 0.3 vs. 2.2 +/- 0.2; p < .05). The number of segments affected in the echocardiograms (EC-S) was: L = 5.3 +/- 0.6 vs. H = 4.4 +/- 0.2; p = 0.11. No significant differences in CK levels, ECG-D, ECG-Q, and EC-S were observed when the patients were separated according their plasma BC levels. These results indicate that a high concentration of plasma VE, but not BC, was associated with a diminution in the creatine phosphokinase release and with the AMI extension.     

Vitamin C deficiency and risk of myocardial infarction: prospective population study of men from eastern Finland.

OBJECTIVE: To examine the association between plasma vitamin C concentrations and the risk of acute myocardial infarction. DESIGN: Prospective population study. SETTING: Eastern Finland. SUBJECTS: 1605 randomly selected men aged 42, 48, 54, or 60 who did not have either symptomatic coronary heart disease or ischaemia on exercise testing at entry to the Kuopio ischaemic heart disease risk factor study in between 1984 and 1989. MAIN OUTCOME MEASURES: Number of acute myocardial infarctions; fasting plasma vitamin C concentrations at baseline. RESULTS: 70 of the men had a fatal or non-fatal myocardial infarction between March 1984 and December 1992.91 men had vitamin C deficiency (plasma ascorbate < 11.4 mumol/l, or 2.0 mg/l), of whom 12 (13.2%) had a myocardial infarction; 1514 men were not deficient in vitamin C, of whom 58 (3.8%) had a myocardial infarction. In a Cox proportional hazards model adjusted for age, year of examination, and season of the year examined (August to October v rest of the year) men who had vitamin C deficiency had a relative risk of acute myocardial infarction of 3.5 (95% confidence interval 1.8 to 6.7, P = 0.0002) compared with those who were not deficient. In another model adjusted additionally for the strongest risk factors for myocardial infarction and for dietary intakes of tea fibre, carotene, and saturated fats men with a plasma ascorbate concentration < 11.4 mumol/l had a relative risk of 2.5 (1.3 to 5.2, P = 0.0095) compared with men with higher plasma vitamin C concentrations. CONCLUSIONS: Vitamin C deficiency, as assessed by low plasma ascorbate concentration, is a risk factor for coronary heart disease.     

CK-MBmass, hs-cTnT及CK-MB与急性心肌梗死的相关性及其联合诊断价值

摘要 目的：研究肌酸激酶同工酶质量（CK-MBmass)、肌酸激酶同工酶（CK-MB）和高敏心肌肌钙蛋白T（hs-cTnT）在急性心肌梗死患者（AMI）血清中的含量,并探讨三者联合对AMIDE诊断价值。方法：选择2018年1月到2021年10月我院收治的AMI患者90例作为研究组,并选择同期在我院体检健康志愿者40例作为对照组,比较两组AMI患者血清CK-MBmass,hs-cTnT和CK-MB。根据Killp分级法将不同心力衰竭将AMI患者分为II、III和IV级,并根据心肌梗死范围将AMI患者分为轻度、中度和重度心肌梗死组。比较不同AMI患者血清CK-MBmass,hs-cTnT和CK-MB。通过受试者工作曲线计算血清CK-MBmass,hs-cTnT和CK-MB联合诊断AMI的阳性预测值、阴性预测值、敏感度和特异度。结果：（1）AMI患者血清CK-MBmass,hs-cTnT和CK-MB均显著高于健康志愿者（P<0.05）;（2）AMI患者血清CK-MBmass,hs-cTnT和CK-MB随Killp分级或心肌梗死范围升高而升高（P<0.05）;（3）AMI患者血清CK-MBmass,hs-cTnT,CK-MB与急性心肌梗死患者左室射血分数（LVEF）呈负相关（P<0.05）,与左室舒张末期容积（LVEDd）和梗死范围呈正相关（P<0.05）;（4）血清CK-MBmass,hs-cTnT和CK-MB联合检测急性心肌梗死的阳性预测值、阴性预测值、敏感度和特异度均高于单独诊断。结论：血清CK-MBmass,hs-cTnT和CK-MB在AMI患者含量升高,并且与患者心功能和心肌梗死范围有关,适用于AMI的联合诊断。     

Dietary intake of carotenoids and retinol and the risk of acute myocardial infarction in Italy

BACKGROUND: Carotenoids may reduce the risk of coronary heart disease through their antioxidant properties, but the results of epidemiological studies are controversial. We analysed the relation between the intake of selected carotenoids and retinol and risk of acute myocardial infarction (AMI). METHODS: A case-control study was conducted in Milan, Italy, in 1995-2003. Cases were 760 patients with nonfatal AMI, and controls 682 patients admitted to hospital. RESULTS: The risk of AMI decreased with increasing intake of alpha-carotene (odds ratios, OR = 0.71, 95% confidence intervals, CI 0.51-0.98, for the highest vs the lowest quartile of intake), beta-carotene (OR = 0.71, 95% CI 0.50-1.01) and beta-criptoxanthin (OR = 0.64, 95% CI 0.46-0.88). No associations emerged for total carotenoids, lycopene, lutein plus zeaxanthin and retinol. CONCLUSIONS: Our study suggests a weak protective effect of alpha-carotene, beta-carotene and beta-criptoxanthin on the risk of AMI. It also indicates that total carotenoids, lycopene, lutein plus zeaxanthin and retinol were not related to the risk of the disease.     

Oxidative stress and potential free radical damage associated with photocopying. A role for ozone?

OBJECTIVE: To study the relationship between oxidative stress and potential free radical damage associated with photocopying and to explore a role for ozone emitted during the photocopying process. METHODS: 80 photocopying operators (PO) and 80 healthy volunteers (HV) were enrolled in a random control study design, in which the level of lipoperoxide (LPO, thiobarbituric acid reactive substances, TBARS) in erythrocytes and the levels of vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as the activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric methods. RESULTS: Compared with the average values of the above biochemical parameters in the HV group, the average value of LPO (TBARS) in erythrocytes in the PO group was significantly increased (P < 0.0001), while the average values of VC, VE and beta-CAR in plasma as well as those of SOD and CAT in erythrocytes in the PO group were significantly decreased (P < 0.0001). Pearson product-moment correlation analysis showed that with the increase of the ozone level in photocopying sites and the PO duration of exposure to ozone, the level of LPO in erythrocytes in the operators was increased (P < 0.001), while the levels of VC, VE and beta-CAR in plasma as well as the activities of SOD and CAT in erythrocytes in the operators were decreased (P < 0.01-0.0001). CONCLUSION: The findings in this study suggest that ozone causes oxidative damage in copier operatives.     

Antioxidant vitamin levels and glutathione peroxidase activity during ischemia/reperfusion in myocardial infarction

The consequences of increased oxidative stress, measured as the level of malondialdehyde (MDA) during ischemia/reperfusion, were studied in 48 patients in the acute phase of myocardial infarction (AMI) and a control group (21 blood donors). The serum levels of alpha-tocopherol and beta-carotene were followed. Immediately after the treatment onset the level of alpha-tocopherol started to decrease, reaching a plateau after 24 h. The consumption of beta-carotene was delayed by 90 min. Steady decline was detected during the whole time interval studied (48 h). Glutathione peroxidase (GPx) activity, as a representative of antioxidant enzymes, was estimated in whole blood. The influx of oxygenated blood was accompanied by a stimulation of GPx activity, which reached its maximum at the time of completed reperfusion. When comparing the AMI patients with the control group, the levels of MDA were found significantly increased, which indicates that oxidative stress is already increased during ischemia. Lower antioxidant levels found in the patients might either already be the result of vitamin consumption during ischemia or be a manifestation of their susceptibility to AMI. Monitored consumption of alpha-tocopherol and beta-carotene during reperfusion indicated that in the case of patients, whose level of antioxidant vitamins is below the threshold limit, a further substantial decrease of antioxidant vitamins during reperfusion could enhance the oxidative damage of the myocardium.     

Vitamin E and beta-carotene status of dairy cows: a survey of plasma levels and supplementation practices

Culling rate in dairy cattle has increased considerably, thereby reducing cowś longevity and raising sustainability concerns worldwide. In the last decades, feeding systems have changed towards larger inclusion of preserved forages and reduced fresh herbage, which may limit vitamin E and beta-carotene dietary supply to dairy cows. Because of higher oxidative stress, engendered by greater milk production of modern genetics, the requirement for these nutrients is increased. Therefore, this study aimed to assess the current status of vitamin E and beta-carotene of commercial dairy cows. Blood vitamin E and beta-carotene concentrations were measured in 2 467 dairy cows from 127 farms in Belgium, Germany, Iberia and The Netherlands, that were visited once. Five cows were randomly selected per lactation stage per farm: Dry (between 30 and 1 day(s) before calving), Very-early (from calving until 15 days in milk (DIM)), Early (between 16 and 119 DIM), and Mid-late (from 120 DIM onwards). In addition, a survey was conducted to retrieve data on vitamin E and beta-carotene supplementation and feeding practices. Vitamin E and beta-carotene blood concentrations dropped considerably around calving. Among all surveyed cows, more than 75 and 44% were deficient in vitamin E and beta-carotene (i.e., blood concentration below 3.0 and 3.5 mg/l, respectively). Of the Very-early group, more than 97 and 78% of the cows were deficient in vitamin E and beta-carotene, respectively, with respective blood concentrations of 1.15 and 2.71 mg/l, which was significantly lower than the other lactation stages. Vitamin E and beta-carotene blood concentrations, as well as their supplementation levels, significantly varied among countries. Vitamin E and beta-carotene blood concentrations were positively related to the total estimated daily intakes of vitamin E and beta-carotene. Therefore, blood concentrations of vitamin E and beta-carotene depend on their respective level of intake, which is generally below recommendations and varies greatly between countries. Supplementation could contribute to provide cows with adequate amounts of vitamin E and beta-carotene all along the lactation, to ensure their lifetime performance and improve their fertility.     

Effect of dietary beta-carotene on the accumulation of beta-carotene and vitamin A in plasma and tissues of gilts

The absorption of beta-carotene in pigs is limited. Nevertheless beta-carotene might positively affect reproduction. In this study the absorption and tissue distribution of beta-carotene as well as its function as precursor of vitamin A was investigated in gilts that were fed according to one of three dietary treatments: VA (4000 IU vitamin A), VA + VA (4000 IU + 8300 IU) and VA + BC (4000 IU + 100 mg beta-carotene per kg diet) for 14 weeks. Only in the VA + BC group was beta-carotene detected in plasma (1-8 ng x mL(-1)), liver, adrenals and corpora lutea, indicating that pigs absorb intact beta-carotene at low rates. Liver levels of vitamin A were higher (P < 0.01) at comparable levels in the VA + VA and VA + BC group than in the VA group, indicating a conversion rate of beta-carotene to vitamin A of 40 to 1 on the basis of weight for beta-carotene at this level (100 mg x kg(-1)) in the diet. Higher levels of vitamin A in the uterus of the VA + BC group (P < 0.01) as well as the accumulation of beta-carotene in adrenals and corpora lutea might reflect some influence of beta-carotene on local vitamin A metabolism which might be of importance for reproductive performance in gilts.     

3,4-Methylenedioxymethamphetamine (MDMA) abuse may cause oxidative stress and potential free radical damage

OBJECTIVE: To investigate whether 3,4-methylenedioxymethamphetamine abuse (MDMA abuse) may cause oxidative stress and potential free radical damage in the bodies of MDMA abusers (MA), and to explore the mechanisms by which MDMA abuse may be causing oxidative stress. METHODS: One hundred and twenty MA and 120 healthy volunteers (HV) were enrolled in a random control study design, in which the level of lipoperoxide (LPO) in erythrocytes, and the levels of Vitamin C (VC), Vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as the activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric methods. RESULTS: Compared with the average values of the above biochemical parameters in the HV group, the average value of LPO in erythrocytes in the MA group was significantly increased (P < 0.0001), while the average values of VC, VE and beta-CAR in plasma as well as those of SOD and CAT in erythrocytes in the MA group were significantly decreased (P < 0.0001). The analysis of bivariate correlations suggested that with the increase of the MDMA abuse dose and the MDMA abuse duration, the level of LPO in erythrocytes in the MA was increased (P < 0.0001), while the levels of VC, VE and beta-CAR in plasma as well as the activities of SOD and CAT in erythrocytes in the MA were decreased (P < 0.0001). CONCLUSION: The findings in this study suggest that MDMA abuse may cause oxidative stress and potential free radical damage to MA.     

Effect of simultaneous administration of vitamin C, L-cysteine and vitamin E on the melanogenesis

The effect of simultaneous administration of vitamin C (ascorbic acid), L-cystein (Cys) and vitamin E (tocopherol) on the melanogenesis in vivo and in vitro was studied. Forty-eight brownish guinea pigs were divided into 4 groups as follows: VC group, VC+Cys group, VC+Cys+VE group and control group. They were given these vitamins by oral administration every day. UV-B exposure (0.384 J/cm2) on their depleted back skin was done at the day 8, 10, 12, 15 17 and 19. After UV-B irradiation, vitamins were administrated further 3 weeks. The luminosity score was measured using a Color Reader CR-11 (Minolta, Co) and the numbers of DOPA-positive melanocytes of their back skin were counted. B16 melanoma cells were incubated with VC, N-acetyl cystein (NAC) and VE. After 4 days of incubation, cells were harvested. The melanin contents and the tyrosinase activities in cells were measured. The luminosity score in the VC+VE+Cys group was higher than those in the other groups. The numbers of DOPA-positive melanocytes of guinea pigs treated with VC, VE and Cys were significantly decreased compared with those in VC group. In B16 melanoma cells, simultaneous treatment of VC, VE and NAC was the most effective to decrease the melanin contents and to inhibit tyrosinase activity.     

Thrombopoietin upregulates nucleolin mRNA and protein in thrombopoietin-dependent megakaryocytic cell line,UT-7/TPO

In a randomized, double-blind, controlled trial, the effects of oral treatment with coenzyme Q10 (CoQ10, 120 mg/day), a bioenergetic and antioxidant cytoprotective agent, were compared for 1 year, on the risk factors of atherosclerosis, in 73 (CoQ, group A) and 71 (B vitamin group B) patients after acute myocardial infarction (AMI). After 1 year, total cardiac events (24.6 vs. 45.0%, p < 0.02) including non-fatal infarction (13.7 vs. 25.3%, p < 0.05) and cardiac deaths were significantly lower in the intervention group compared to control group. The extent of cardiac disease, elevation in cardiac enzymes, left ventricular enlargement, previous coronary artery disease and elapsed time from symptom onset to infarction at entry to study showed no significant differences between the two groups. Plasma level of vitamin E (32.4 ± 4.3 vs. 22.1 ± 3.6 umol/L) and high density lipoprotein cholesterol (1.26 ± 0.43 vs. 1.12 ± 0.32 mmol/L) showed significant (p < 0.05) increase whereas thiobarbituric acid reactive substances, malondialdehyde (1.9 + 0.31 vs. 3.1 + 0.32 pmol/L) and diene conjugates showed significant reduction respectively in the CoQ group compared to control group. Approximately half of the patients in each group (n = 36 vs. 31) were receiving lovastatin (10 mg/day) and both groups had a significant reduction in total and low density lipoprotein cholesterol compared to baseline levels. It is possible that treatment with CoQ10 in patients with recent MI may be beneficial in patients with high risk of atherothrombosis, despite optimal lipid lowering therapy during a follow-up of 1 year. Adverse effect of treatments showed that fatigue (40.8 vs. 6.8%, p < 0.01) was more common in the control group than CoQ group.     

C4b-binding protein is present in affected areas of myocardial infarction during the acute inflammatory phase and covers a larger area than C3

Background

During myocardial infarction reduced blood flow in the heart muscle results in cell death. These dying/dead cells have been reported to bind several plasma proteins such as IgM and C-reactive protein (CRP). In the present study we investigated whether fluid-phase complement inhibitor C4b-binding protein (C4BP) would also bind to the infarcted heart tissue.

Methods and Findings

Initial studies using immunohistochemistry on tissue arrays for several cardiovascular disorders indicated that C4BP can be found in heart tissue in several cardiac diseases but that it is most abundantly found in acute myocardial infarction (AMI). This condition was studied in more detail by analyzing the time window and extent of C4BP positivity. The binding of C4BP correlates to the same locations as C3b, a marker known to correlate to the patterns of IgM and CRP staining. Based on criteria that describe the time after infarction we were able to pinpoint that C4BP binding is a relatively early marker of tissue damage in myocardial infarction with a peak of binding between 12 hours and 5 days subsequent to AMI, the phase in which infiltration of neutrophilic granulocytes in the heart is the most extensive.

Conclusions

C4BP, an important fluid-phase inhibitor of the classical and lectin pathway of complement activation binds to jeopardized cardiomyocytes early after AMI and co-localizes to other well known markers such as C3b.     

Dietary supplementation with antioxidants. Is there a case for exceeding the recommended dietary allowance?

The containment of damaging oxygen species by antioxidant nutrients has led to the speculation that the RDA for these specific nutrients may be overly low. Among these nutrients are vitamin E, vitamin C, and to a lesser extent beta-carotene and selenium. Evidence for the role of these nutrients in cancer and heart disease is evaluated. The case is presented for an increase of two-fold for the vitamin C RDA and between three and five-fold for vitamin E; for establishing 15 mg as the RDA for beta-carotene; for no change in the vitamin A RDA; and for further study on selenium.     

曲美他嗪联合麝香保心丸治疗急性心肌梗死的效果研究

目的:研究曲美他嗪(TMZ)联合麝香保心丸(HMP)治疗急性心肌梗死的效果。方法:采用40只雄性C57BL/6J小鼠构建急性心肌梗死模型,随机分成4组,每组10只:(1)假手术组;(2)心肌梗死组;(3)心肌梗死+TMZ组(TMZ 20 mg/Kg灌胃,3次/天);(4)心肌梗死+TMZ+HMP组(HMP 14 mg/Kg灌胃,3次/天)。2周后行心脏超声检查采集心功能参数左室舒张末内径、左室收缩末内径、室间隔厚度、舒张末期左室后壁厚度及射血分数。同时,对心脏标本行形态学分析。结果:TMZ+HMP组左室舒张末内径、左室收缩末内径、舒张末期左室后壁厚度及射血分数均优于于TMZ组(均为P0.05)。心肌组织HE及PSR染色显示TMZ+HMP组心肌细胞坏死及纤维化程度较其余组低。结论:曲美他嗪联合麝香保心丸治疗急性心肌梗死的效果较单用曲美他嗪更加显著。     

Immunoglobulin E and matrix metalloproteinase-9 in patients with different stages of coronary artery diseases

The aims of this study were to identify levels of total immunoglobulin E (IgE) and matrix metalloproteinase (MMP)-9 in patients with different stages of coronary artery diseases. IgE, MMP-9, creatine phosphokinase (CPK), lactate dehydrogenase (LDH), total cholesterol, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL) and triglyceride (TG) were measured by fluorescence enzyme immunoassay, gelatin zymography, and autoanalyzer in normal subjects (n = 40), patients with stable angina pectoris (SAP, n = 40), patients with unstable angina pectoris (UAP, n = 40), patients with acute myocardial infarction (AMI, n = 40), or post-CABG-surgery of those acute myocardial infarction (P-CABG, n = 40). Compared with normal subjects, increased IgE but unchanged MMP-9, CPK, LDH were found in SAP group and UAP group, whereas IgE, MMP-9, CPK and LDH levels were all significantly increased in AMI group. IgE, MMP-9, CPK and LDH levels in P-CABG group were significantly reduced, compared with AMI group, and were similar to those in normal subjects. Cholesterol, LDL, HDL and TG were not significantly changed in all groups. We suggest that serum total IgE can be an early marker of coronary artery disease and MMP-9 is a marker of acute myocardial infarction.     

急性心肌梗死伴新发束支传导阻滞的临床意义

目的:观察急性心肌梗死伴新发左、右束支传导阻滞的临床特点,评价束支阻滞对急性心肌梗死预后的影响。方法:对上海交通大学附属第一人民医院心内科重症监护室2010年1月1日到12月31日收治的197例急性心肌梗死患者的病历资料进行回顾性分析,根据束支传导阻滞有无及类型分为左束支传导阻滞组(12例),右束支传导阻滞组(19例)和对照组(无束支传导阻滞的急性心梗,166例)。分析和比较三组患者的基线资料,心梗部位、Killip分级、恶性室性心律失常、左室射血分数LVEF、病变血管数量、梗死相关冠脉、住院天数及病死率、实验室检查(BNP,心肌损伤标志物峰值)。结果:LBBB组AMI患者的恶性心律失常发生率明显高于对照组(P=0.007),LVEF明显低于RBBB组和对照组(P值分别为0.020、0.045),梗死相关动脉以LAD多见。结论:急性心梗伴束支传导阻滞往往提示病情严重,预后不良,急性心梗合并左束支阻滞较合并右束支阻滞病情更严重。     

Predictive value of circulating miR-328 and miR-134 for acute myocardial infarction

MicroRNA (miRNAs) is demonstrated to be present in the blood of humans and has been increasingly suggested as a novel biomarker for various pathological processes in the heart, including myocardial infarction, myocardial remodeling and progression to heart failure. In this study, we aim to evaluate the diagnostic and prognostic value of circulating miR-328 and miR-134 in patients with acute myocardial infarction (AMI). Circulating levels of miR-328 and miR-134 were detected by quantitative real-time PCR in plasma samples from 359 AMI patients and 30 healthy volunteers. Concentrations of high-sensitivity cardiac troponin T (hs-cTnT) were measured using electrochemiluminescence-based methods. MiRNAs were assessed for discrimination of a clinical diagnosis of AMI and for association with primary clinical endpoint defined as a composite of cardiogenic death and development of heart failure within 6 months after infarction. Results showed that levels of plasma miR-328 and miR-134 were significantly higher in AMI patients than in healthy controls. Receiver operating characteristic curve analyses showed significant diagnostic value of miR-328 and miR-134 for AMI. However, neither of them was superior to hs-cTnT for the diagnosis. Additionally, increased miRNA levels were strongly associated with increased risk of mortality or heart failure within 6 months for miR-328 (OR 7.35, 95 % confidence interval 1.07–17.83, P < 0.001) and miR-134 (OR 2.28, 95 % confidence interval 1.03–11.32 P < 0.001). In conclusion, circulating miR-328 and miR-134 could be potential indicators for AMI, and the miRNA levels are associated with increased risk of mortality or development of heart failure.     

早期康复训练对冠心病介入治疗术后恢复的影响

目的:探讨经皮冠脉介入(PCI)治疗的急性心肌梗死(AMI)患者行早期康复训练后的疗效与安全性。方法:192例AMI患者经PCI治疗后随机分为康复组与对照组各96例,分别予早期心脏程序康复训练与传统康复治疗。比较2组患者的心脏结构、并发症及住院时间。结果:在住院期间及随访1年后,两组患者左室舒张末内径、左室收缩末内径、左室后壁厚度及左室射血分数无统计学差异(P>0.05);心律失常、心绞痛及死亡率等并发症均无显著性差异(P>0.05);而对照组院内感染发生率明显多于康复组(P<0.05)。结论:AMI患者PCI术后行早期心脏程序康复训练安全、有益,可明显减少院内感染的发病率,缩短住院时间。     

Benign coxsackievirus damages heart muscle in iron-loaded vitamin E-deficient mice

Several oxidative stressors (dietary selenium deficiency, dietary vitamin E deficiency coupled with fish oil feeding, genetic reduction of glutathione peroxidase activity) allow a normally benign coxsackievirus B3 (CVB3/0) to damage heart muscle in host mice. This study investigated whether dietary iron overload, another oxidant stress, would also permit CVB3/0 to exert a cardiopathologic effect in vitamin E-deficient (-VE) mice. Four groups of mice were fed either a -VE or a +VE diet containing either an adequate or an excessive (30x) amount of iron. After 4 weeks of feeding, the mice were inoculated with CVB3/0 and heart damage was assessed at various times postinfection. Mice fed a diet sufficient in VE with excess iron developed heart damage equivalent to mice fed a diet deficient in vitamin E without excess iron. However, severe heart damage occurred in the group fed a diet deficient in VE with excess iron, which was the most pro-oxidative diet. The highest heart viral titers were found in mice fed the -VE/excessive iron diet. However, the extent of heart damage did not always correlate with the formation of TBARS in liver homogenates. Further research is needed to clarify the role of oxidative stress and iron overload in determining the course of viral infection.     

Role of ventilation strategy on perfluorochemical evaporation from the lungs.

To study the effect of ventilation strategy on perfluorochemical (PFC) elimination profile (evaporative loss profile; E(L)), 6 ml/kg of perflubron were instilled into anesthetized normal rabbits. The strategy was to maintain minute ventilation (VE, in ml/min) in three groups: VE(L) (low-range VE, 208 +/- 2), VE(M) (midrange VE, 250 +/- 9), and VE(H) (high-range VE, 293 +/- 1) over 4 h. In three other groups, respiratory rate (RR, breaths/min) was controlled at 20, 30, or 50 with a constant VE and adjusted tidal volume. PFC content in the expired gas was measured, and E(L) was calculated. There was a significant VE- and time-dependent effect on E(L.) Initially, percent PFC saturation and loss rate decreased in the VE(H) > VE(M) > VE(L) groups, but by 3 h the lower percent PFC saturation resulted in a loss rate such that VE(H) < VE(M) < VE(L) at 4 h. For the groups at constant VE, there was a significant time effect on E(L) but no RR effect. In conclusion, E(L) profile is dependent on VE with little effect of the RR-tidal volume combination. Thus measurement of E(L) and VE should be considered for the replacement dosing schemes during partial liquid ventilation.