年龄相关的循环内皮祖细胞变化与动脉弹性关系的研究

目的　研究年龄对循环内皮祖细胞及动脉弹性的影响,探讨循环内皮祖细胞水平与动脉弹性损伤的关系。方法　56例健康男性志愿者分成青年组(n=26)和老年组(n=30)。采用桡动脉脉搏分析法无创性评价健康志愿者大动脉弹性指数(C1 )和小动脉弹性指数(C2 ), 流式细胞仪测定外周血中CD34+单个核细胞的水平,单个核细胞体外培养2周,荧光显微镜鉴定FITC UEA I和DiI acLDL双染色阳性细胞为内皮祖细胞。结果　老年组与青年组相比较,C1 和C2 明显降低[C1(11. 73±1 .45)比(16 .89±1 .69)ml/mmHg×10, P<0. 001; C2 (8 .40±1 45)比(10. 58±1 .18)ml/mmHg×100, P<0 .001 ];循环内皮祖细胞数目明显减少[ ( 0 .13±0. 02 )比( 0 .17±0. 04 )%,P<0 .05];循环内皮祖细胞水平与动脉弹性指数变化呈正相关(r=0. 47, P<0. 01;r=0 .4, P<0. 01),荧光显微镜鉴定贴壁细胞FITC UEA I和DiI acLDL双染色阳性。结论　增龄导致循环内皮祖细胞数量减少,提示血管内皮修复能力下降和功能障碍,损伤动脉弹性,循环内皮祖细胞水平有可能作为评价血管功能的替代指标。     

Circulating endothelial progenitor cell deficiency contributes to impaired arterial elasticity in persons of advancing age

Reduced arterial elasticity is a hallmark of ageing in healthy humans and appears to occur independently of coexisting disease processes. Endothelial-cell injury and dysfunction may be responsible for this fall in arterial elasticity. We hypothesized that circulating endothelial progenitor cells (EPCs) are involved in endothelial repair and that lack of EPCs contributes to impaired arterial elasticity. A total of 56 healthy male volunteers were divided into young (n=26) and elderly (n=30) groups. Large and small artery elasticity indices were noninvasively assessed using pulse wave analysis. The number of circulating EPCs was measured by using flow cytometry. Cells demonstrating DiI-acLDL and FITC-ulex lectin double-positive fluorescence were identified as EPCs. C1 large artery elasticity and C2 small artery elasticity indices were significantly reduced in the elderly group compared with the young group (11.73+/-1.45 vs 16.88+/-1.69 ml/mm Hg x 10, P<0.001; 8.40+/-1.45 vs 10.58+/-1.18 ml/mm Hg x 100, P<0.001, respectively). In parallel, the number of circulating EPCs was significantly reduced in the elderly group compared with the young group (0.13+/-0.02 vs 0.17+/-0.04%, P<0.05). The number of circulating EPCs correlated with C1 large and C2 small artery elasticity indices (r=0.47, P<0.01; r=0.4, P<0.01). The present findings suggest that the fall in circulating EPCs with subsequently impaired endothelial-cell repair and function contributes to reduced arterial elasticity in humans with ageing. The decrease in circulating EPCs may serve as a surrogate biologic measure of vascular function and human age.     

Impaired endothelial progenitor cell activity is associated with reduced arterial elasticity in patients with essential hypertension

Endothelial dysfunction is related to reduced arterial elasticity in patients with essential hypertension. Circulating endothelial progenitor cells (EPCs), an important endogenous repair approach for endothelial injury, is altered in hypertensive patients. However, the association between alteration in circulating EPCs and hypertension-related reduced arterial elasticity has not been reported. The purpose of this study is to investigate the association between alteration in circulating EPCs and hypertension-related reduced arterial elasticity. We measured the artery elasticity profiles including brachial-ankle PWV (baPWV) and C1 large and C2 small artery elasticity indices in patients with essential hypertension (n = 20) and age-matched normotensive subjects (n = 21). The number and activity of circulating EPCs isolated from peripheral blood were determined. Compared to normotensive subjects, the patients with hypertension exhibited decreased C1 large and C2 small artery elasticity indices, as well as increased baPWV. The number of circulating EPCs did not differ between the two groups. The migratory and proliferative activities of circulating EPCs in hypertensive patients were lower than those in normotensive subjects. Both proliferatory and migratory activities of circulating EPCs closely correlated with arterial elasticity profiles, including baPWV and C1 large and C2 small artery elasticity indices. Multivariate analysis identified both proliferative and migratory activities of circulating EPCs as independent predictors of the artery elasticity profiles. The present study demonstrates for the first time that impaired activity of circulating EPCs is associated with reduced arterial elasticity in patients with hypertension. The fall in endogenous repair capacity of vascular endothelium may be involved in the pathogenesis of hypertension-related vascular injury.     

Endothelial microparticles correlate with endothelial dysfunction in obese women

CONTEXT: Cell-derived microparticles are supposed to be involved in atherogenesis. OBJECTIVE: This study aimed to evaluate circulating microparticles in obese women and their relation with anthropometric measures and endothelial dysfunction. DESIGN, SETTING, AND PARTICIPANTS: Forty-one obese [body mass index (BMI) > 30 kg/m(2)] women and 40 normal weight (BMI < 25 kg/m(2)) age-matched women were studied. Flow cytometry was used to assess microparticles by quantification of circulating endothelial microparticles (EMP, CD31+/CD42b-) and platelet microparticles (PMP, CD31+/CD42b+) in peripheral blood; endothelium-dependent flow-mediated vasodilation (FMD) was evaluated in the right brachial artery after reactive hyperemia. RESULTS: Compared with lean women, obese women presented significantly higher numbers of EMP and PMP, and reduced FMD. BMI did not correlate with either EMP (r = 0.02, P = 0.9) or PMP (r = -0.07, P = 0.645), whereas waist-to-hip ratio (WHR) showed significant correlation with both microparticles (r = 0.699, P < 0.001; r = 0.373, P = 0.016, respectively). Both EMP and PMP counts positively correlated with impairment of FMD in obese women. Multivariate analysis correcting for age, anthropometric indices, lipid parameters, and PMP identified EMP as the only independent predictor for impaired endothelial-dependent vasodilation (P = 0.003). CONCLUSIONS: EMP are elevated in obese women and independently involved in the pathogenesis of endothelial dysfunction. WHR is the anthropometric measure more closely related to EMP and endothelial dysfunction.     

Arterial elasticity among normotensive subjects and treated and untreated hypertensive subjects

OBJECTIVE: The aim of this study was to determine arterial elasticity in normotensive and hypertensive individuals. BACKGROUND: In addition to blood pressure, other parameters serve as markers for vascular disease. Arterial elasticity is one parameter that can be determined by a modified Windkessel model of the circulation. This model estimates, from a computerized pulse contour analysis, the proximal (capacitive) elasticity of the large arteries and the distal (reflective) elasticity of the small arteries. METHODS: A prospective, multi-center, controlled clinical study evaluated large-artery and small-artery elasticity indices in four groups: (1) normotensives without a family history of hypertension; (2) normotensives with a family history of hypertension; (3) treated and controlled hypertensives; and (4) untreated and uncontrolled hypertensives. Blood pressure, using a mercury manometer, and arterial elasticity, using a CVProfilor DO-2020 CardioVascular Profiling System (Hypertension Diagnostics, Inc., Eagan, MN, USA), were measured supine in triplicate 3 min apart in a randomized sequence. RESULTS: There were 212 evaluable subjects of mean age 46 years; 57% were women, 51% Caucasian and 33% African-American. Comparing normotensives without a family history and untreated hypertensives, both large-artery and small-artery elasticity indices were significantly different (P < 0.0001). After controlling for age and body surface area, a significant linear trend (P = 0.0001) across the four groups was detected for both large- and small-artery elasticity indices. CONCLUSION: As the hypertension status worsened, large- and small-artery elasticity indices decreased, suggesting a potential for the diagnostic use of arterial elasticity determinations.     

Reduced arterial elasticity is associated with endothelial dysfunction in persons of advancing age: comparative study of noninvasive pulse wave analysis and laser Doppler blood flow measurement

BACKGROUND: Endothelial dysfunction is the earliest marker for age-related abnormalities in vascular function, and examination of endothelial function has important clinical relevance. The present study was performed to evaluate effects of aging on arterial elasticity by using pulse waveform analysis and to investigate whether the changes in arterial elasticity might be used as a noninvasive measure for endothelial dysfunction. METHODS: A total of 24 healthy male volunteers were divided into young (n = 12) and elderly (n = 12) groups. Endothelial function was evaluated by delivering acetylcholine (Ach) and sodium nitroprusside (SNP) to the forearm vessels using iontophoresis, respectively, and measured blood flow using laser Doppler fluximetry. Large and small artery elasticity indices were noninvasively assessed using pulse wave analysis. RESULTS: Basal blood flow was similar between the young and elderly groups (14.58 +/- 3.4 v 13.52 +/- 3.41 PU, P = NS). Peak blood flow induced by Ach was significantly reduced in the elderly group compared with the young group (83.4 +/- 11.9 v 93.75 +/- 10.87 PU, P < .05). However, peak blood flow induced by SNP was similar in the two groups (119.17 +/- 16.76 v 128.33 +/- 21.29 PU, P = NS). In parallel, C1 large artery elasticity and C2 small artery elasticity indices were significantly reduced in the elderly group compared with the young group (11.42 +/- 1.67 v 16.75 +/- 2.09 mL/mm Hg x 10, P < .001; and 7.67 +/- 1.56 v 10.75 +/- 1.86 mL/mm Hg x 100, P < .001, respectively). The Ach-induced peak blood flow correlated with C1 large and C2 small artery elasticity indices. CONCLUSIONS: Advancing age is associated with endothelial dysfunction and reduced arterial elasticity. Reduced arterial elasticity parallels changes in impaired endothelium dependent vasodilation. It appears that reduced arterial elasticity may be used as a noninvasive measure for the determination of endothelial function.     

冠心病患者血管内皮功能障碍与动脉弹性关系的研究

目的　探讨冠心病患者血管内皮功能障碍与动脉弹性的关系。方法　采用高分辨率血管超声法检测 30例冠心病患者与 30例正常对照组肱动脉血流介导的内皮依赖性血管舒张功能(FMD);应用动脉弹性功能检测仪测定受试者的大动脉弹性指数 (C1 )和小动脉弹性指数 (C2 )。结果　冠心病组血流介导的肱动脉舒张反应明显低于对照组[ (5 17±2 13)% 与 (11 10±4 36)%,P<0 05];冠心病组与正常对照组的C1 差异无统计学意义 [ ( 11 59±4 56 )ml/mmHg( 1mmHg=0 133kPa) ×10与 (12 11±3 82)ml/mmHg×10, P>0 05],但冠心病组的C2 明显低于正常对照组[ (4 20±1 80)ml/mmHg×100与 (6 26±2 36)ml/mmHg×100, P<0 05],冠心病组血流介导的肱动脉舒张反应与C2 呈正相关(r=0 53, P<0 05)。结论　冠心病患者肱动脉内皮依赖血管舒张功能受损和C2 降低,且两者之间呈正相关,提示C2 可作为一种评价血管内皮功能的新指标。     

Relationship between arterial elasticity indices and carotid artery intima-media thickness

Functional and structural changes of the arterial wall appear to serve as early hallmarks of the hypertensive disease process. Structural vascular changes can be studied by the determination of the intima-media wall thickness (IMT) at the carotid artery. The elastic behavior of the proximal and distal parts of the arterial tree can be assessed from noninvasively recorded radial artery waveforms. The aim of the study was to compare large (proximal, C1) and small (distal, C2) artery elasticity indices in two age-matched study groups with high- and low-normal blood pressure (BP) and to assess the relation between elasticity indices and IMT. A total number of 22 subjects with high-normal BP (40 +/- 2 years; BP, 147 +/- 2.5/84 +/- 1.5 mm Hg) and 22 matched controls with low-normal BP (40 +/- 2 years; BP, 123 +/- 1.9/69 +/- 1.5 mm Hg) were enrolled. The IMT was echographically determined at the common carotid artery by the leading-edge technique. Large artery (C1) and small artery (C2) elasticity indices were calculated from a third-order, four-element model of the arterial circulation. In the group with high-normal BP large and small artery elasticity indices were significantly decreased versus controls with low-normal BP (C1: 1.63 +/- 0.08 v 1.99 +/- 0.09 mL/mm Hg, P < .01; C2: 0.059 +/- 0.005 v 0.076 +/- 0.007 mL/ mm Hg, P < .05) and IMT increased significantly (0.607 +/- 0.039 v 0.516 +/- 0.027 mm, P < .05). Moreover, there was an inverse relationship between IMT and small artery elasticity index (r = -0.60, P = .004). In subjects with a high-normal BP there is already a change in the IMT of the carotid artery versus normotension. The IMT is related to the small artery elasticity index (C2).     

Berberine-induced mobilization of circulating endothelial progenitor cells improves human small artery elasticity

Berberine (BR) has been proved to promote endothelial function. However, the exact mechanisms underlying the effect of BR on endothelial function are not completely clear. It has been demonstrated that endothelial progenitor cells (EPCs) contribute to improvement of endothelial function and C2 small artery elasticity index is a surrogate parameter for the clinical evaluation of endothelial function. We hypothesized that BR-induced mobilization of circulating EPCs is associated with BR-related improvement of endothelial function. To address this assumption, 15 healthy volunteers were recruited and received BR 0.4 g three times per day for 30 days. The number of circulating CD34/KDR double-positive cells as well as C1 large and C2 small artery elasticity indices were evaluated before and after BR therapy. The number of CD34/KDR double-positive EPCs increased significantly after BR treatment (0.030+/-0.020% vs 0.017+/-0.010%, P<0.01). After 30-day BR therapy C2 increased significantly (6.21+/-2.80 ml per mm Hg x 100 vs 4.06+/-2.67 ml per mm Hg x 100, P<0.01) and C1 remained unchanged (10.79+/-3.27 ml per mm Hg x 10 vs 10.06+/-2.08 ml per mm Hg x 10, P>0.05). The increment of CD34/KDR double-positive EPCs was positively correlated with the increment of C2 (r=0.68, P<0.01). We concluded that BR-induced mobilization of circulating EPCs contributes to improvement of small artery elasticity in healthy persons.     

Performance of the UA-787 oscillometric blood pressure monitor according to the European Society of Hypertension protocol

OBJECTIVE: To determine the accuracy of the UA-787 oscillometric blood pressure monitor developed by the A&D Company. DESIGN: Evaluation of the UA-787 was performed using the new protocol of the European Society of Hypertension. The performance of the monitor was assessed in relation to the subjects' gender, age, skinfold thickness, arm circumference, body mass index and elasticity index of large (C1) and small (C2) arteries. METHODS: The UA-787 monitor was assessed according to European Society of Hypertension requirements, which are based on four zones of accuracy differing from the mercury standard by 5, 10, 15 mmHg, or more. In all subjects (n=33), indices of large-artery elasticity (C1) and small-artery elasticity (C2) were measured with the HDI/Pulsewave CR-2000 Research Cardiovascular Profiling System. RESULTS: The UA-787 passed all three phases of the protocol for both systolic and diastolic blood pressure. The mean blood pressure difference between device and the observers was 1.0+/-5.3 mmHg for systolic pressure, and 0.7+/-5.3 mmHg for diastolic pressure. In univariate analysis, the discrepancy between device and the observers was related to forearm circumference (P=0.02) for systolic pressure. For diastolic blood pressure, a significant relationship was found only for heart rate (P<0.01). However, in a multivariable regression analysis no clinical variable was an independent predictor of device-observer discrepancy. In particular, the performance of the UA-787 appeared to be uniform across the whole range of C1 and C2. CONCLUSIONS: These data show that the A&D UA-787 device satisfies the new recommended European Society of Hypertension accuracy levels for both systolic and diastolic pressure. Its performance is uniform across sub-groups of subjects with different clinical characteristics.     

高血压病患者循环内皮微颗粒水平与动脉弹性功能关系的研究

目的:研究高血压病患者循环内皮微颗粒水平和动脉弹性功能的关系。方法:采用流式细胞仪技术测定高血压病患者(n=60,高血压组)和健康志愿者(n=32,对照组)血浆中CD31+/CD42-内皮微颗粒的水平,袖带震荡技术无创检测肱动脉与胫后动脉之间的肱踝脉搏波传导速度,评估二者之间的相关性。结果:与对照组相比,高血压患者循环内皮微颗粒水平显著升高[(972.6±116.2)比(1920.3±152.0)个/μl,P<0.001];高血压组患者肱踝脉搏波传导速度增快[(1369.3±147.3)比(1793.0±328.3)cm/s,P<0.001]。循环内皮微颗粒水平与肱踝脉搏波传导速度呈正相关(r=0.42,P<0.001),以肱踝脉搏波传导速度为因变量的多因素回归分析显示,循环内皮微颗粒水平是其独立影响因素。结论:高血压病患者循环内皮微颗粒水平升高且肱踝脉搏波传导速度加快,循环内皮微颗粒是肱踝脉搏波传导速度的独立影响因素,提示高血压病患者体内较高水平的循环内皮微颗粒加速了大动脉弹性功能减退。     

Relationship between periventricular or deep white matter lesions and arterial elasticity indices in very old people

OBJECTIVE: To examine the relationship between the presence of cerebral white matter lesions and large and small artery elasticity indices in a population of healthy, very old subjects. METHODS: We studied 24 subjects (14 women, 10 men) with a mean age of 84+/-5 years, who were free from overt neurological, cardiovascular or psychiatric illness. We measured blood pressure and heart rate in supine and standing positions. Elasticity indices of the large arteries (C1) and small arteries (C2) were derived from radial artery pulse waves. Each subject had multi-slice spin-echo cerebral magnetic resonance imaging. The severity of white matter lesions was graded as 0, 1 or 2. RESULTS: Cerebral white matter lesions on magnetic resonance imaging were common in very old apparently healthy subjects: grade 0 (n=4, C1=2.68+/-1.80 ml/mmHg and C2=0.045+/-0.017 ml/mmHg), grade 1 (n=7, C1=2.13+/-0.36 ml/mmHg and C2=0.040+/-0.016 ml/mmHg) and grade 2 (n=13, C1=1.12+/-0.36 ml/mmHg and C2=0.018+/-0.003 ml/mmHg). There was no significant association between elasticity indices and blood pressure. CONCLUSION: In very old, apparently healthy subjects, both large and small artery elasticity indices were inversely related to the severity of cerebral white matter lesions on magnetic resonance imaging.     

Novel Compliance Index derived from digital volume pulse associated with risk factors and exercise capacity in patients undergoing treadmill exercise tests

OBJECTIVE: Although large-artery stiffness is a well-known independent factor for cardiovascular risk, the importance of small-artery stiffness is not well elucidated. We have developed a novel Compliance Index as a marker of small-artery stiffness. This study aimed to determine the clinical significance of this index by evaluating 140 patients without left ventricular dysfunction referred for treadmill exercise tests. METHODS: Immediately after a 10-min rest period before the test, the pulse wave velocity and Compliance Index were measured. The patients were then given a symptom-limited treadmill test using Bruce's protocol. Our dual-channel photoplethysmography system automatically measured the area under the curve of each digital volume pulse, which represented the volume change in the finger with each heart beat. The Compliance Index was calculated by dividing the area under the curve of finger digital volume pulse by pulse pressure. RESULTS: The Compliance Index was significantly correlated with pulse wave velocity (r=-0.254, P=0.002), systolic blood pressure (r=-0.606, P<0.001), and diastolic blood pressure (r=-0.323, P<0.001). It was lower in males (3.3+/-1.4 versus 4.8+/-2.4 units, P<0.001), in hypertensive patients (3.2+/-1.5 versus 4.4+/-2.2 units, P<0.001), and in smokers (3.0+/-1.5 versus 4.1+/-2.1 units, P=0.006). CONCLUSIONS: The Compliance Index was lower in patients with risk factors and was associated with poor exercise capacity. This index may be clinically useful for evaluating arterial stiffness.     

The mobilization of CD34 positive mononuclear cells after myocardial infarction is abolished by revascularization of the culprit vessel

BACKGROUND: The mobilization of hematopoietic progenitor cells from bone marrow has been proposed to play a role in cardiac regeneration after myocardial infarction (MI). Accordingly, an increase in CD34 positive cells (CD34+) has been observed in the peripheral blood of patients after acute myocardial infarction. Here, we evaluated the influence of an acute percutaneous coronary intervention (PCI) of the occluded artery on the mobilization of CD34+ in acute MI. METHODS: CD34 positive cells were quantified by flow cytometry (FACS analysis) and expressed as number per million white blood cells. Peripheral blood was obtained and analyzed at day 5 after the onset of symptoms from patients with acute MI without early PCI (n=11, age 63+/-5 years), acute MI with rapid PCI (n=7, age 63+/-3), patients with pneumonia (n=5, age 51+/-6), patients without angiographical signs of coronary artery disease (control, n=5, age 66+/-8) and young healthy volunteers (n=11, age 28+/-1). RESULTS: Patients with MI but without PCI had a higher CD34+ count at day 5 (312+/-48 per 10(6) leukocytes) than control (156+/-40, P=0.03) and MI with PCI (173+/-31, P=0.03). No increase in CD34+ was observed in patients who underwent PCI vs. control. Patients with pneumonia had higher CD34+ (350+/-44) than patients with MI with PCI (P=0.01) and control (P=0.01). Healthy individuals who were much younger than all other groups (28+/-1 years, P<0.0001 vs. all groups) had the highest CD34+ (526+/-51, P=0.006 vs. MI without PCI, P=0.00003 vs. MI with PCI, P=0.02 vs. pneumonia, P=0.00006 vs. control). CONCLUSIONS: Shorter time of ischemia and reduced cell death may be the reasons for reduced CD34+ cell count after acute MI with early percutaneous intervention vs. acute MI without intervention. Besides ischemia, also inflammation as present in pneumonia may cause a mobilization of CD34+ cells. Age may be a major factor that influences the mobilization of CD34+ cells and the regenerative capacity of the heart.     

Comparison of arterial elasticity measured in left and right arms using the HDI/Pulsewave CR-2000 Research System

BACKGROUND: Arterial elasticity is implicated as a risk factor for or a marker of cardiovascular disease. Current advances in non-invasive devices have now made it possible to measure arterial elasticity in an ambulatory setting. OBJECTIVE: The aim of this study was to determine whether there is a difference in blood pressure and arterial elasticity measured in the right and the left arms. METHODS: Simultaneous measurements were performed with two HDI/Pulsewave CR-2000 Research CardioVascular Profiling Systems. The manufacturer recommends placing the blood pressure cuff on the left upper arm and the sensor on the skin overlying the right radial artery. We followed the manufacturer's recommendations and also placed both the cuff and the sensor on the same arm. Simultaneous measurements were made on both arms with both machines. The average of three measurements was used for each combination. Systolic and diastolic blood pressure, and large-artery and small-artery elasticity indices, were determined for each subject and used in the analysis. RESULTS: The subjects were 11 males and 9 females between 22 and 46 (33.5 +/- 7.4 years) years of age. There was no significant difference in the average difference for each test combination. CONCLUSION: Thus, when using the HDI/Pulsewave CR-2000 Research CardioVascular Profiling System, the blood pressure cuff and the sensor can be placed on either the same arm or opposite arms.     

Detection of circulating p24 antigen-positive CD4+ cells during HIV infection by flow cytometry.

OBJECTIVES: To determine the amount of circulating CD4+ cells positive for intracellular p24 antigen during HIV infection, and to correlate the results with clinical, virological and therapeutic parameters. METHODS: Data were obtained from 24 anti-HIV-negative subjects (controls) and 47 anti-HIV-positive patients classified according to clinical diagnosis, serum p24-antigen assay results, and antiretroviral treatment with zidovudine, using a modified flow cytometric assay for the detection of intracellular HIV p24 antigen (p24-FCA) in circulating CD4+ lymphocytes. RESULTS: The proportion of CD4+ lymphocytes positive for p24-FCA correlated well with HIV infection (1.685 +/- 1.902 versus 0.160 +/- 0.152 in controls; P < 0.001) and clinical progression [Centers for Disease Control (CDC) stage II: 1.310 +/- 1.187; CDC stage III 1.145 +/- 1.442; CDC stage IVA/C2: 2.335 +/- 2.112; CDC stage IVC1: 2.066 +/- 2.420]. The percentage of CD4+ cells positive for HIV p24-FCA was inversely correlated with an absolute peripheral blood CD4+ lymphocyte count (Spearman's rank correlation = -0.324; P < 0.05). However, there was no statistically significant difference between patients in presence (n = 27; 1.938 +/- 2.095) or absence (n = 20; 1.343 +/- 1.594) of serum p24 Ag. The variable linked most strongly to the detection of intracellular p24 in anti-HIV-positive patients was zidovudine treatment: the proportion of p24-FCA-positive CD4+ lymphocytes was significantly lower (0.825 +/- 0.910) in the treated patients (n = 25) than in the untreated patients (n = 22; 2.662 +/- 2.248; P < 0.001). CONCLUSIONS: Our results suggest that CD4+ p24 Ag-FCA is a rapid and easy test for the identification of the proportion of CD4+ lymphocytes with intracellular p24 Ag, and that it could be more appropriate than serum p24 Ag assay in evaluating disease progression and efficacy of antiretroviral treatment.     

男性高血压患者睾酮与动脉顺应性关系的研究

目的 探讨男性高血压患者睾酮与动脉顺应性的关系.方法 按照收缩压≥140 mm Hg(1 mm Hg=0.133 kPa)和(或)舒张压≥90 mm Hg诊断为高血压的标准,将277例受试者分为男性对照组、男性高血压组、女性对照组和女性高血压组.采用CVProfilor DO-2020动脉脉搏分析仪分别测定各组受试者大动脉顺应性(C1)、小动脉顺应性(C2),用酶促化学发光法检测血清睾酮浓度,用放免法检测血清胰岛索浓度.结果 (1)男女性高血压组C1、C2均显著低于相应对照组,血清睾酮浓度在男性高血压组低于男性对照组(P均<0.01),而在女性两组问比较差异无统计学意义.(2)睾酮在男性组与C1、C2正相关,与血压、甘油三酯、血糖、体质指数、胰岛素抵抗指数负相关.在女性组与体质指数负相关(P均<0.05).(3)多元逐步回归分析表明,年龄、睾酮足影响男性血压的主要因素,年龄、C2、体质指数是影响女性血压的主要因素.结论 动脉顺应性减退是高血压的预测指标;中年男性血清睾酮水平下降与动脉顺应性减退密切相关,是男性发生高血压的主要危险因素之一.     

No age-related change in circulating endothelial progenitor cells in healthy subjects

Endothelial progenitor cells were isolated from peripheral blood obtained from 32 healthy volunteers without cardiovascular risk factors who ranged in age from 20 to 61 years (mean [+/- SD] age, 34.1 +/- 9.6 years). The fractions of CD34(+) endothelial progenitor cells expressing kinase insert domain receptor-1, CD62E, or CD31 were analyzed with flow cytometry. Correlation analysis demonstrated that there was no significant correlation between subject age and the fraction of circulating CD34(+) mononuclear cells expressing kinase insert domain receptor-1 (P = 0.324; r = -0.180). Similarly, there was no significant correlation between subject age and the fraction of circulating CD34(+) mononuclear cells expressing CD62E (P = 0.496; r = -0.125) or the fraction of circulating CD34(+) mononuclear cells expressing CD31 (P = 0.245; r = -0.212). In conclusion, the experimental results showed that there was no age-related change in the basal level of circulating endothelial progenitor cells in healthy subjects without cardiovascular risk factors.     

Effects of GH replacement on endothelial function and large-artery stiffness in GH-deficient adults: a randomized, double-blind, placebo-controlled study

OBJECTIVES: Hypopituitary adults with growth hormone deficiency (GHD) have an increased cardiovascular mortality, although the mechanisms remain unclear. Endothelial dysfunction, characterized by reduced nitric oxide (NO) bioavailability, is a key early event in atherogenesis and is associated with increased vascular smooth muscle tone and arterial stiffening. DESIGN AND PATIENTS: In a randomized, double-blind, placebo-controlled study, we investigated the effects of GH replacement on endothelial function and large-artery stiffness in 32 GHD adults (19 males, 13 females) (age range 19-64 years) over a 6-month period. Thirty-two age- and sex-matched healthy controls were also studied. MEASUREMENTS: Endothelial function was assessed using ultrasonic wall tracking to measure flow-mediated dilatation (FMD) of the brachial artery. Large artery stiffness was assessed by pulse wave analysis of the radial artery pressure waveform, allowing determination of the corresponding central arterial pressure waveform and derivation of the augmentation index. Fasting lipid profiles, glucose and insulin were also measured. RESULTS: At baseline, FMD (mean +/- SD) was impaired in GH-deficient subjects vs. controls (3.4 +/- 2.3 vs. 5.7 +/- 2.0%, P < 0.0001), although endothelium-independent dilatation was similar. The augmentation index was higher in GH-deficient subjects vs. controls (23 +/- 12 vs. 14 +/- 14%, P < 0.01). GH-deficient subjects had higher LDL cholesterol (4.1 +/- 0.8 vs. 3.5 +/- 0.8 mmol/l, P < 0.01) and lower HDL cholesterol (1.1 +/- 0.3 vs. 1.4 +/- 0.4 mmol/l, P < 0.01). In GH-deficient subjects, there were inverse correlations between LDL cholesterol and FMD (r = -0.40, P < 0.05) and between FMD and the augmentation index (r = - 0.58, P < 0.01). Regression analysis identified FMD as an independent predictor of the augmentation index (P < 0.0001). In comparison with baseline, GH replacement resulted in an increase in FMD (5.0 +/- 2.6 vs. 2.8 +/- 1.9%, P < 0.01). There were decreases in central aortic systolic pressure (117 +/- 15 vs. 123 +/- 17 mmHg, P < 0.01), diastolic pressure (82 +/- 10 vs. 86 +/- 8 mmHg, P < 0.01) and the augmentation index (22 +/- 8% vs. 26 +/- 10%, P < 0.05) despite unchanged brachial pressure indices. LDL cholesterol also decreased (3.5 +/- 0.8 vs. 4.2 +/- 0.8 mmol/l, P < 0.01). There were no significant changes in the placebo group. CONCLUSIONS: Adult GHD is associated with endothelial dysfunction and increased large-artery stiffness. An improvement in endothelial function and a reduction in arterial stiffness following GH replacement suggests an important therapeutic role for GH in reducing cardiovascular risk associated with adult GHD.     

Relation of small artery compliance and lipoprotein (a) in patients with atherosclerosis

BACKGROUND: Lipoprotein (a) is suggested to cause endothelial dysfunction, alteration of elastic arterial properties, and decreased arterial compliance. We investigated the relation of arterial compliance and lipoprotein (a) serum [Lp(a)] levels in patients with atherosclerosis. METHODS: Prospective study included 118 consecutive patients with atherosclerosis. Noninvasive computerized pulse wave analysis was used to measure large and small artery elasticity indices in a nondiseased vessel area. Compliance parameters were correlated to Lp(a) levels. Stratified and multivariate analyses were performed to adjust for confounding factors. RESULTS: Small artery elasticity index was inversely correlated with Lp(a) serum levels (r = -0.64, P <.001). The association between Lp(a) and small artery elasticity index remained significant adjusting for age, sex, diabetes mellitus, smoking, hyperlipidemia, and lipid-lowering medication (r = -0.37, P <.0001). Lp(a) accounted for approximately 60% of the variation of small artery compliance in nondiabetic patients (n = 80) (r = -0.76, P <.0001), in diabetic patients (n = 38) no significant correlation between Lp(a) and small artery compliance was observed (r = -0.27, P =.09). No correlation was found between large artery elasticity index and Lp(a). CONCLUSIONS: Small artery compliance was negatively correlated to Lp(a) in nondiabetic patients with atherosclerosis. Increased Lp(a) serum levels might cause endothelial dysfunction measurable by decreased small artery elasticity index in these patients. Elastic properties of diabetic vessels were not directly related to Lp(a) serum levels.