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81.
The objective of this study was to determine the effect of alpha-linolenic acid (ALA) supplementation on blood lipids and inflammatory markers, in relation to apolipoprotein (apo) E genotype. The diets of 50 dyslipidemic male patients were supplemented with 15 mL of flaxseed oil per day for 12 weeks. Retrospectively, 3 apo E genotype variants were found (epsilon2/epsilon3, n=7; epsilon3/epsilon3, n=33; epsilon3/epsilon4, n=10). No significant differences were found among apo E genotypes in any variables at baseline. ALA supplementation produced a small but significant decrease in high-density lipoprotein cholesterol (from 1.12 to 1.08 mmol/L, 43 to 42 mg/dL; p=0.008) and apo A-I levels (from 1.28 to 1.24 g/L, p=0.036) in the epsilon3/epsilon3 homozygotes. In addition, ALA supplementation resulted in a significant decrease in the serum concentration of serum amyloid A (SAA) (p=0.014), C-reactive protein (CRP) (p=0.013), macrophage colony-stimulating factor (MCSF) (p<0.001), and interleukin (IL)-6 (p=0.028). Serum SAA and MCSF were also significantly decreased in the epsilon3/epsilon4 group (p=0.005 and p=0.017, respectively). In contrast, ALA produced no effects on any of the inflammatory markers in the epsilon2/epsilon3 group. ALA may have beneficial effects on inflammation in dyslipidemic carriers of the apo epsilon3/epsilon3 and epsilon3/epsilon4 genotypes, but not in carriers of the epsilon2 allele.  相似文献   
82.
The purpose of this work was to evaluate the relation between serum glucose levels at hospital admission and left ventricular systolic function in nondiabetic patients with an acute coronary syndrome (ACS). Of the 1000 ACS patients who were consecutively enrolled during 2007–2008, 583 (63 ± 13 years, 20% females) nondiabetic patients were studied in this work. Of these, 254 presented left ventricular systolic dysfunction (ejection fraction <40%). Biochemical measurements and detailed medical information were recorded in all participants. Patients having glucose levels at hospital admission in the highest tertile (>155 mg/dl) had lower left ventricular ejection fraction (40% vs 45%, P = 0.003), were older (66 ± 11 vs 61 ± 13, P = 0.004) and less physically active (49% vs 63%, P = 0.02), had higher troponin (14.7 ± 39.7 vs 5.6 ± 13.5, P = 0.03), higher brain natriuretic peptide (510.39 ± 932.33 vs 213.4 ± 301.14, P = 0.008), higher C-RP (42.26 ± 55.26 vs 26.46 ± 38.18, P = 0.04), lower creatinine clearance levels (68 ± 33 vs.81 ± 31, P = 0.009), higher white blood cell count (13 416 ± 16 420 vs 9310 ± 3020, P = 0.001), and lower body mass index (26.8 ± 4 vs 27.2 ± 4.4, P = 0.07), compared to those in the lowest tertile (<114 mg/dl). The multiadjusted logistic regression analysis revealed that a 10 mg/dl difference in glucose levels was independently associated with 8% (95% confidence interval 2%–14%) higher likelihood of left ventricular systolic dysfunction. Low glucose concentrations at hospital admission in nondiabetic post-ACS patients is a predictor for the appearance of left ventricular dysfunction, and could be a target marker for risk stratification.  相似文献   
83.
The aim of this work was to assess the 5-year incidence of hypertension and its predictors among prehypertensive adults. Under the context of the ATTICA Study, data from 1188 individuals, free of cardiovascular disease, but with defined high blood pressure levels (prehypertension) at baseline examination (during 2001–2002) were retrieved. In 2006, the 5-year follow-up of the study was performed, and 798 of the prehypertensive participants were allocated. In this work, incidence and determinants of developing hypertension were evaluated. The 5-year ageadjusted incidence of hypertension was 18.7% in men and 24.6% in women (P = 0.05); while almost one half of prehypertensive individuals at the age of 55–65 years developed hypertension, and approximately 6 out of 10 people over 65 years of age developed the disease. Multiple logistic regression analysis revealed that increased age (odds ratio [OR] per 1 year = 1.09, 95% confidence interval [CI] 1.07–1.12), male sex (OR = 0.40, 95% CI 0.21–0.68), high education status (OR per 1 year of school = 0.94, 95% CI 0.88–0.98), waist circumference (OR per 1 cm = 1.04, 95% CI 1.02-1.06) and C-reactive protein (OR per 1 mg/l = 1.12, 95% CI 1.05–1.20), were positively associated with the development of hypertension. Moreover, greater adherence to Mediterranean diet seems to protect only prehypertensive, with abdominal obesity patients prone to develop hypertension (OR = 0.94, 95% CI 0.90–0.98). Annual incidence of hypertension was roughly 4% in men and women. Older people, with low education, abdominal obesity, lower adherence to the Mediterranean diet, and increased inflammation, constitute a model of prehypertensive individuals that are prone to develop hypertension.  相似文献   
84.
OBJECTIVE: In this work we assessed a risk score for developing a first event of acute coronary syndrome (ACS) based on the family history of the cardiovascular risk factors. METHODS AND RESULTS: The studied population consisted of 848 randomly selected middle-aged patients with first event of ACS and 1078 sex-age-region matched controls admitted to the same hospitals for minor operations and without any clinical suspicion of cardiovascular disease in their life. A Family History Score (FHS) was developed based on the presence of coronary heart disease, hypertension, hypercholesterolaemia and diabetes mellitus, among first-degree relatives of the participants after adjusting for the family size. The evaluation of FHS was based on conditional logistic regression analysis, after controlling for demographic variables as well as for the mutual confounding effects of other risk factors. Family history of CHD, hypercholesterolaemia and diabetes was highly associated with the development of the disease. The introduced FHS was also highly associated with the development of ACS among participants who had no family history of CHD (odds ratio = 10.9, p < 0.001), whereas it was not associated with the development of the disease among participants who had a family history of CHD (odds ratio = 1.41, p = 0.543). CONCLUSIONS: The suggested FHS could be a useful tool in the primary prevention of ACS, as well as in detecting and understanding associations between genetic vulnerability and cardiovascular risk factors.  相似文献   
85.
Background and aimEating behaviours and obesity status among children have already been evaluated in several studies, with conflicting results. The aim of this study is to assess the correlation of breakfast cereal with childhood obesity.Methods and resultsA representative sample of 700 children (323 male) selected from 18 schools located in Athens greater area were enrolled. Children and their parents completed questionnaires that evaluated dietary habits and physical activity. We also retrieved information about the type of breakfast most frequently consumed. Height and weight of the children was measured and body mass index (BMI) was calculated. Simple and multiple logistic regression methods were used in order to determine the relationship between cereal intake for breakfast and obesity.Some boys (8.6%) and girls (9.0%) were obese, whereas 33.9% of boys and 22.1% of girls were overweight. For boys, the adjusted odds ratio for breakfast cereal intake for being overweight or obese was 0.54 (95% confidence interval (CI): 0.45–1.29), while for girls it was 0.41 (95% CI: 0.21–0.79). Moreover, the odds ratio of overweight/obesity for boys who ate daily breakfast was 0.51 (95% CI: 0.25–1.05), and for girls was 0.27 (95% CI: 0.12–0.64), adjusted for physical activity and other potential confounders.ConclusionThese data provide evidence that breakfast cereal as a most frequent choice, and daily consumption of breakfast, are inversely associated with the prevalence of overweight or obesity in 10–12-year-old children.  相似文献   
86.
The amino acid intermediate homocysteine (Hcy) is formed during the metabolism of methionine to cysteine. Hyperhomocysteinemia (HHcy) is recognized as an independent risk factor for coronary atherosclerosis. The circulating levels of total Hcy (tHcy) can increase due to intake of foods rich in methionine or deficiencies of vitamins such as folate, pyridoxine and cyanocobalamin, which are required for the metabolism of Hcy. In addition, mutations in the genes coding for Hcy metabolizing enzymes can contribute to an increase in tHcy levels. Clinical and epidemiological studies have shown that an elevated level of tHcy measured in serum or plasma is a strong predictor of cardiovascular disease risk, which appears to be greatest in patients who have HHcy following a methionine load. Intimal hyperplasia (IH) (intima/media [I/M] ratio) is the universal response of a vessel to injury and may result in vasoconstriction when left unattended. The effect of dietary HHcy on balloon catheter-injured carotid artery and its modulation (if any) by the peroxisome proliferator-activated receptor agonist gamma rosiglitazone was evaluated in 12-week-old female Sprague-Dawley rats fed either a control diet or a diet containing 1% L-methionine. Once the rats were established on the diet, the group that was fed 1% L-methionine was further subdivided and either given an aqueous preparation of 3 mg/kg/day rosiglitazone or the vehicle via oral gavage for one week. This was followed by surgically injuring the left carotid artery using a Maverick Over-The-Wire catheter (2.0 mm × 20 mm, 3.2F; Boston Scientific, USA). The rats were continued on their respective diets and drug regimen for 21 days postsurgery. On day 22 of the procedure, the rats were sacrificed for collection of blood, the carotid arteries and liver for biochemical and histological evaluation. Compared with controls there was a significant increase in both tHcy levels and I/M ratio in the rats fed 1% L-methionine (5.4±0.28 μM versus 32.8±3.01 μM, P<0.002; and 0.175±0.05 versus 1.05±0.23, P<0.005, respectively). The effect of rosiglitazone in rats fed the control diet was not prominent. On the other hand, administration of rosiglitazone to the rats on the 1% L-methionine diet significantly reduced the levels of serum tHcy (16.6±2.1 μM versus 32.8±3.01 μM, P<0.001); however, the tHcy levels remained significantly elevated compared with animals on the control diet (P<0.002). The group receiving the L-methionine diet plus rosiglitazone had an inhibition in the development of IH compared with those receiving the L-methionine diet alone (I/M of 0.278±0.041 versus 1.05±0.23, P<0.01). Moreover, the development of IH in the group receiving the L-methionine diet plus rosiglitazone treatment was not significantly different from that observed in the group on the control diet without rosiglitazone (0.278±0.041 versus 0.175±0.05, respectively). These findings may have important implications in deciphering the molecular mechanisms involved in the augmentation of IH in HHcy and modulation of this process by rosiglitazone.  相似文献   
87.
Nolta  JA; Smogorzewska  EM; Kohn  DB 《Blood》1995,86(1):101-110
We sought to define optimal conditions for retroviral-mediated transduction of long-lived human hematopoietic progenitors from bone marrow and peripheral blood. CD34+ cells were transduced by the LN and G2 retroviral vectors in the presence or absence of stromal support and with or without cytokine addition. After transduction, a portion of the cells was plated in methylcellulose colony-forming assay, with or without G418, to assess the extent of gene transfer into committed progenitors. The remaining cells from each experiment were transplanted into immunodeficient mice to allow analysis of transduction of long- lived progenitors. Human colony-forming cells contained within the murine bone marrow were analyzed after engraftment periods of 2 to 11 months. Cells were plated in a human-specific colony-forming assay with and without G418 to assess the extent of transduction of primitive progenitors. Individual human colonies were also analyzed by polymerase chain reaction for the presence of provirus. Bone marrow progenitors were efficiently transduced only when stroma was present, whereas mobilized peripheral blood progenitors were effectively transduced in the presence of either stroma or cytokines. Inclusion of the cytokines interleukin-3, interleukin-6, and stem cell factor did not further augment the extent of gene transfer in the presence of a stromal support layer. Additionally, human CD34+ progenitors from bone marrow or mobilized peripheral blood that had been transduced for 3 days in the absence of stroma failed to produce sustained, long-term engraftment of bnx mice. Mice transplanted with the same pools of human progenitors that had been transduced in the presence of stroma for 3 days had significant levels of human cell engraftment at the same timepoints, 7 to 11 months after transplantation. Our data show loss of long-lived human progenitors during 3-day in vitro transduction periods in the absence of stromal support. Therefore, the presence of bone marrow stroma has dual benefits in that it increases gene transfer efficiency and is essential for survival of long-lived human hematopoietic progenitors.  相似文献   
88.
Hasan  AA; Cines  DB; Ngaiza  JR; Jaffe  EA; Schmaier  AH 《Blood》1995,85(11):3134-3143
An important biologic function of high-molecular-weight kininogen (HK) is to deliver bradykinin (BK) to its cellular receptors. Internalization and degradation of HK may provide a mechanism by which endothelial cells modulate the production of BK and control its activities. Therefore, we investigated the binding and subsequent distribution of biotinylated-HK (biotin-HK) associated with human umbilical vein endothelial cells (HUVEC). HUVEC bound 3 to 4 times more HK and with greater avidity at 1 to 3 hours at 37 degrees C than at 4 degrees C (Bmax = 1.0 +/- 0.02 x 10(7) molecules/cell, kd = 7 +/- 3 nmol/L v Bmax = 2.6 +/- 0.2 x 10(6) molecules/cell, kd = 46 +/- 8 nmol/L). However, there was no evidence that the difference was caused by internalization of HK at the higher temperature. First, the same amount of biotin-HK was associated with nonpermeabilized and permeabilized HUVEC using buffers containing 20 to 50 mumol/L zinc ion in the absence or presence of 2 mmol/L calcium ion. Second, binding of biotin-HK to HUVEC was approximately 92% reversible at 1 hour when the cells were maintained at both 37 degrees C and 4 degrees C. Third, neither chloroquine nor primaquine altered the amount of biotin-HK bound to HUVEC. Fourth, biotin-HK bound to HUVEC was almost completely removed by pronase. Fifth, the nonpermeable dye, crystal violet, almost completely quenched the fluorescence signal emitted by HUVEC-associated fluorescein isothiocyanate (FITC) HK. Finally, the localization of HUVEC-bound FITC-HK was restricted to the membrane as shown by laser scanning confocal microscopy. The expression of HK binding sites had an absolute requirement for metabolic energy, but was not dependent on new protein synthesis. Membrane-bound HK contributed to the anticoagulant nature of endothelial cells by blocking human alpha-thrombin binding and its resultant induction of prostacyclin formation. These studies indicate that HK is not internalized by HUVEC, but remains primarily on cell surfaces to be accessible for BK liberation and to modulate the binding and actions of alpha-thrombin.  相似文献   
89.
Background and aimsThe 5-year incidence of cardiovascular disease (CVD) in relation to dietary habits, among men and women from Greece, was evaluated.Methods and resultsFrom May 2001 to December 2002, 1514 men and 1528 women (>18 years) without any clinical evidence of CVD, living in the Attica area, Greece, were enrolled in the ATTICA study. In 2006, a group of experts performed the 5-year follow-up (941 of the 3042 participants were lost). Development of CVD (coronary heart disease, acute coronary syndromes, stroke, or other CVD) during the follow-up period was defined according to WHO ICD-10 criteria. Principal Components Analysis was applied, and 15 dietary patterns were extracted (71% of total information explained) from 26 foods or food groups.The 5-year incidence of CVD was 11.0% in men and 6.1% in women (p < 0.001); the case fatality rate was 1.6%. Multi-adjusted analysis revealed that the dietary pattern that was mainly characterized by cereals, small fish, hardtack and olive oil intake, was associated with lower CVD risk (HR per 1 unit = 0.72, 95% CI 0.52–1.00); the pattern that was characterized by fruits, vegetables intake and olive oil use in daily cooking was associated with lower CVD risk (HR per 1 unit = 0.80, 95% CI 0.66–0.97); while patterns that were mainly characterized by sweets, red meat, margarine, salty nuts intake, and hard cheese, as well as alcohol intake, were associated with higher CVD risk (HR per 1 unit = 1.26, 95% CI 1.01–1.56, and HR per 1 unit = 1.32, 95% CI 1.05–1.66, respectively).ConclusionsMultivariate statistical methods revealed dietary patterns based on empirical epidemiological data which were associated with the development of CVD.  相似文献   
90.
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