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21.
Endothelial progenitor cells (EPCs) are mobilized from the bone marrow into the peripheral circulation, home to sites of injury, and incorporate into foci of neovascularization, thereby improving blood flow and tissue recovery. Patients with cardiovascular diseases, including coronary artery disease, heart failure, hypertension, and diabetes, have been shown to exhibit reduced number and functional capacity of EPCs. Considerable evidence indicates that EPCs constitute an important endogenous system to maintain endothelial integrity and vascular homeostasis, while reduced number of EPCs has recently been shown to predict future cardiovascular events. Thus, enhancement of EPCs could be of potential benefit for individuals with cardiovascular diseases. The interplay between inflammation and oxidative stress is involved in the initiation, progression, and complications of cardiovascular diseases. Emerging evidence from in vitro and clinical studies suggests that inflammatory and oxidative changes influence EPC mobilization. Drugs with anti-inflammatory and antioxidant properties, currently administered to patients with cardiovascular diseases, such as statins, have been demonstrated to exert beneficial effects on EPC biology. A better understanding of the inflammatory and oxidative mechanisms leading to the numerical and functional impairment of EPCs would provide additional insight into the pathogenesis of cardiovascular disease and create novel therapeutic targets.  相似文献   
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BACKGROUND: Tea consumption is associated with decreased cardiovascular risk. Flow-mediated dilatation (FMD) of the brachial artery is related to coronary endothelial function and it is an independent predictor of cardiovascular risk. Black tea has a beneficial effect on endothelial function; the effect, however, of green tea on brachial artery reactivity has not been defined yet. DESIGN AND METHODS: We studied 14 healthy individuals (age 30+/-3 years) with no cardiovascular risk factors except from smoking (50%) on three separate occasions on which they took: (a) 6 g of green tea, (b) 125 mg of caffeine (the amount contained in 6 g of tea), or (c) hot water. FMD of the brachial artery was measured before each intervention and 30, 90, and 120 min afterward. High-sensitivity C-reactive protein, interleukins 6 (Il-6) and 1b (Il-1b), total plasma antioxidative capacity, and total plasma oxidative status/stress were measured at baseline and at 120 min after each intervention. RESULTS: Resting and hyperemic brachial artery diameter did not change either with tea or with caffeine. FMD increased significantly with tea (by 3.69%, peak at 30 min, P<0.02), whereas it did not change significantly with caffeine (increase by 1.72%, peak at 30 min, P=NS). Neither tea nor caffeine had any effect on high-sensitivity C-reactive protein, Il-6, Il-1b, total plasma antioxidative capacity, or total plasma oxidative status/stress. CONCLUSION: Green tea consumption has an acute beneficial effect on endothelial function, assessed with FMD of the brachial artery, in healthy individuals. This may be involved in the beneficial effect of tea on cardiovascular risk.  相似文献   
23.
BACKGROUND: This study investigates the correlation of hepatic progenitor cells (HPC) expression with treatment response in patients with chronic hepatitis C. DESIGN: The study comprised 77 liver biopsies with chronic hepatitis C (HCV). All patients were PCR-HCV (+) and received antiviral therapy with interferon or pegylated interferon alpha-2b and ribavirin. Twenty-nine patients were assigned as responders (group A), 29 as nonresponders (group B) and 19 as relapsers (group C). Ten normal liver biopsies were used as controls. Liver paraffin sections were subjected (a) to immunohistochemistry using antibodies for cytokeratins 19 (CK19) and 7 (CK7), alpha-fetoprotein (AFP), leukocyte common antigen (LCA) and CD34 antigen (b) to in situ hybridization for AFP mRNA and (c) to immunohistochemistry+in situ hybridization. Results were expressed as % of positive cells following morphometric analysis. RESULTS: HPC expression was present in all 87 specimens. In the control biopsies, rare HPC were detected. In the CH cases and according to AFP mRNA expression, the grade for % HPC expression was: group B: 53.2+/-2.6> group C: 48.37+/-1.8> group A: 31.4+/-1.6 (group A vs B P<0.01, group A vs C P<0.01, group B vs C P>0.05. Double stain revealed that HPC coexpressed CK19/AFP mRNA, CK7/AFP mRNa and AFP protein/AFP mRNA. HPC-percentages were directly correlated with total HAI score (P<0.01), fibrosis stage (P<0.01), and transaminase values (P<0.05). CONCLUSIONS: This study demonstrates that in cases of chronic hepatitis C, the significant association of HPC expression with the severity of disease and more specifically with the response to treatment implies that HPC development and proliferation may provide additional prognostic information and predict prognosis in such cases.  相似文献   
24.

Background

The aim of this study was to investigate the effects of iloprost, on colonic anastomotic healing in rats, under obstructive ileus conditions.

Materials and methods

Eighty male Albino rats were randomized into four groups of 20 animals each. They underwent colonic resection followed by an inverted anastomosis. The rats of group 1 (control) and group 2 (ileus) received 3 mL of saline 0.9% intraperitoneally and those of group 3 (iloprost), and group 4 (ileus + iloprost) iloprost (2 μg/kg of body weight), immediately postoperatively and daily until the day of sacrifice. Each group was further divided into two equal subgroups, depending on the day of sacrifice. The animals of subgroup “a” were sacrificed on the fourth postoperative day, whereas those of “b” on the eighth day. Macroscopic and histologic assessment was performed, whereas anastomotic bursting pressures and the tissue concentrations in hydroxyproline and collagenase I were evaluated.

Results

Means of bursting pressure, neoangiogenesis, fibroblast activity, and hydroxyproline concentration were significantly increased in group 4 compared with group 2. In addition, on the fourth postoperative day, the inflammatory cell infiltration and the collagenase I concentration were significantly decreased in group 4 compared with group 2. Moreover, on the eighth postoperative day, collagen deposition was significantly increased in group 4 compared with group 2.

Conclusions

Iloprost after intraperitoneal administration reverses the negative effect of obstructive ileus. It promotes not only the angiogenic activity but also collagen formation, resulting in increased bursting pressures on the fourth and eighth postoperative days.  相似文献   
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The aim of this study was to investigate the association of breakfast consumption with children’s diet quality and cardiometabolic risk factors. Study sample consisted of 1558 children aged 4–8 years from Cyprus. Breakfast frequency was assessed through a parental questionnaire. Body mass index (BMI), BMI z-scores, waist circumference, blood lipid profile and blood pressure were examined in relation to breakfast frequency consumption. Habitual breakfast consumers’ daily nutrient intake was assessed through a 24-Hour Dietary Recall, according to their breakfast choices. Girls who have breakfast on a daily basis had lower mean BMI and BMI z-score; they were also less likely of having abnormal levels of serum triglycerides, atheromatic index (total cholesterol to high density lipoprotein-cholesterol ratio) and diastolic blood pressure after controlling for several confounding factors. Within regular breakfast consumers, of both boys and girls, those having ready to eat cereals had a superior nutrient intake profile. Daily breakfast consumption along with good breakfast choices is an important public health message for Cypriot children.  相似文献   
28.
Acute or subacute thrombosis and late restenosis remain the main limitations of permanent stenting. In an effort to address these limitations, an autologous vein graft-coated stent (AVGCS) was developed at our institution. This stent consists of a conventional stent (Palmaz or Palmaz-Schatz, Johnson and Johnson), which is covered by an autologous vein graft. After successful experimental implantation, we report here the immediate results of the percutaneous implantation of AVGCS in 7 patients with coronary artery disease (6 de novo lesions and 1 bailout case). The results of this preliminary study indicate that the preparation of the AVGCS is easy and feasible. The Implantation of the AVGCS was uncomplicated, and the immediate angiographic results were excellent. This new type of coated stent may be useful in addressing current limitations of balloon angioplasty. © 1996 Wiley-Liss, Inc.  相似文献   
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Despite the remarkable development of the medical industry in the current era, herbal products with therapeutic potentials arise as attractive alternative treatments. Consequently, Chios mastiha, a natural, aromatic resin obtained from the trunk and brunches of the mastic tree, has recently gained increasing scientific interest due to its multiple beneficial actions. Chios mastiha is being exclusively produced on the southern part of Chios, a Greek island situated in the northern Aegean Sea, and its therapeutic properties have been known since Greek antiquity. There is now substantial evidence to suggest that mastiha demonstrates a plethora of favorable effects, mainly attributed to the anti-inflammatory and anti-oxidative properties of its components. The main use of mastiha nowadays, however, is for the production of natural chewing gum, although an approval by the European Medicines Agency for mild dyspeptic disorders and for inflammations of the skin has been given. The aim of this article is to summarize the most important data about the therapeutic actions of Chios mastiha and discuss future fields for its medical application.  相似文献   
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