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OBJECTIVE: We previously reported that intrauterine undernutrition increased the oxidative stress by decreasing superoxide dismutase activity. In the present study, we tested whether NADPH oxidase, xanthine oxidase, cyclooxygenase or nitric oxide synthase are responsible for the increased O(2)(-) generation observed in rats submitted to intrauterine undernutrition. In addition, we investigated the effect of angiotensin II (ANG II) on O(2)(-) production via activation of NADPH oxidase. METHODS: Female pregnant Wistar rats were fed either normal or 50% of the normal intake diets, during the whole gestational period. At 16 weeks of age, the rats were used for the study of intravital fluorescence microscopy; microvascular reactivity, local ANG II concentration and AT(1), p22(phox) and gp91(phox) gene expression. In this study only the male offspring was used. RESULTS: Treatment of mesenteric arterioles with the xanthine oxidase inhibitor oxypurinol, the nitric oxide synthase inhibitor L-NAME or the cyclooxygenase inhibitor diclofenac did not significantly change superoxide production. Thus, these vascular sources of superoxide were not responsible for the increased superoxide concentration. In contrast, treatment with the NADPH oxidase inhibitor apocynin significantly decreased superoxide generation and improved vascular function. On the other hand, intrauterine undernutrition did not alter the gene expression for p22(phox) and gp91(phox). The fact that the local ANG II concentration was increased and the attenuation of oxidative stress by blocking AT(1) receptor with losartan, led us to suggest that ANG II induces O(2)(-) generation in intrauterine undernourished rats. CONCLUSION: Our study shows that NADPH oxidase inhibition attenuated superoxide anion generation and ameliorated vascular function in rats submitted to intrauterine undernutrition. Although it is not clear which mechanisms are responsible for the increase in NADPH oxidase activity, a role for ANG II-mediated superoxide production via activation of NADPH oxidase is suggested.  相似文献   
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This multicenter, prospective, open-label, single-arm study determined the efficacy and safety of irbesartan/hydrochlorothiazide (HCTZ) fixed combinations in patients (n=1005), aged 18 years and older, with uncontrolled systolic blood pressure (SBP) of 140-159 mm Hg (130-159 mm Hg for type 2 diabetes mellitus) after at least 4 weeks of antihypertensive monotherapy. Treatment was sequential: placebo (4-5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and irbesartan/HCTZ 300/25 mg (8 weeks). Enrolled patients (n=844) were aged 57.3+/-11.2 years; 52% were women, 23% were African American, and 14% were Hispanic. Thirty percent had type 2 diabetes mellitus, 46% had metabolic syndrome, and baseline blood pressure was 154.0+/-10.3/91.3+/-8.8 mm Hg. The mean change in SBP from placebo end to the primary end point, Week 18 (intent-to-treat population, n=736) was -21.5+/-14.3 mm Hg (p<0.001). The mean change in diastolic blood pressure (DBP) was -10.4+/-8.7 mm Hg (p<0.001). The mean Week 18 SBP/DBP was 132.9+/-13.8/81.1+/-9.7 mm Hg. Overall, 77% (95% confidence interval, 74%-80%) of patients achieved SBP goal (<140 mm Hg; <130 mm Hg for type 2 diabetes mellitus); 83% (95% confidence interval, 80%-86%) achieved DBP goal (<90 mm Hg; <80 mm Hg for type 2 diabetes mellitus); and 69% (95% confidence interval, 66%-72%) achieved dual SBP/DBP goal. Treatments were well tolerated. This irbesartan/HCTZ treatment regimen achieved SBP goals in more than 75% of patients uncontrolled on monotherapy.  相似文献   
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Subgroup analysis of the Irbesartan/Hydrochlorothiazide Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of irbesartan/hydrochlorothiazide (HCTZ) fixed combinations in patients aged 65 years or older with uncontrolled systolic blood pressure (SBP) after >or= 4 weeks of antihypertensive monotherapy. The INCLUSIVE trial was a prospective, open-label, single-arm trial carried out in 119 sites. Of 844 patients completing placebo treatment, 212 were aged 65 years or older. Participants received treatment with placebo (4-5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and then irbesartan/HCTZ 300/25 mg (8 weeks). From baseline to week 18 (n=184, intent-to-treat population), mean change in SBP was -23.0+/-13.3 mm Hg (P<.001) and diastolic BP (DBP) was -10.9+/-7.7 mm Hg (P<.001). Mean SBP/DBP at study end was 134.0+/-14.7/75.1+/-8.4 mm Hg, and SBP, DBP, and SBP/DBP goal was achieved in 73%, 96%, and 72% of patients, respectively. Irbesartan/HCTZ combination therapy allowed SBP goal attainment in 73% of patients aged 65 years or older whose hypertension was previously uncontrolled with antihypertensive monotherapy.  相似文献   
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Propolis is known to possess antioxidant activity. However, there is no information on this activity in emulsions O/W. The protective effect of propolis on the oxidation and rheological properties of emulsions O/W containing wheat germ and almond oils was evaluated. Emulsions O/W were prepared with different concentration of propolis extract, almond oil and wheat germ oil. All emulsions physically stable without phase separation were stored at 37?°C for 9?weeks. Chemical composition of propolis was established by Gas chromatography coupled to mass spectrometry. Rheological characterization of different emulsions was performed evaluating consistency index and flow behavior index. The oxidation was monitored by measuring the lipid hydroperoxides and thiobarbituric acid-reactive substances (TBARS) methods. Flavonoids, phenolic acid esters, and aromatic acids were the main groups of compounds found in propolis. The results showed that popolis was good antioxidant in the concentration of 0.02 and 0.04% when lipid phase was constituted by almond oil. The rheological behavior is typical of a non-Newtonian fluid, being almond oil more adequate for having a higher stable O/W emulsion.  相似文献   
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Objectives Many obesity-related chronic diseases originate from unhealthy childhood habits. The aim of this study was to describe 9-month-old infants’ physical activity levels and patterns and to examine the correlates. Understanding these factors is necessary for improving the effectiveness of physical activity intervention programs for infants. Methods In total, 143 infant–mother dyads from Macau, SAR China, participated in this study. Physical activity (PA) was assessed by using the Actigraph GT3X+ accelerometer and the demographic variables were collected by questionnaires. Results The most important findings were that: (1) infants had more screen time during weekdays (p?=?.044); (2) infants and mothers were least active at 8 a.m. (both weekdays and weekends) in the morning and most active at 7 p.m. (weekdays) and 8 p.m. (weekends) in the evening; (3) infants’ PA levels significantly correlated with their mothers’ PA intensities during the weekends (r?=?.192, p?=?.036), especially the mothers’ lower intensities in the mornings and evenings; (4) maternal BMI predicted the PA levels of the 9-month-old infants’ (R2?=?.06, β?=?29.188, p?=?.009). Conclusions for Practice Physical activity promotion programs for infants should be time-specific starting from early infancy. This study was one of the first to examine 9-month-old infants’ PA levels, patterns and correlates. The results may be helpful in improving the effectiveness of future healthy lifestyle intervention programs for infants in Macau and in the region in general.  相似文献   
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Low‐density lipoprotein cholesterol (LDL‐C) levels are significantly associated with atherosclerotic cardiovascular disease (ASCVD) risk, and studies using interventions that lower LDL‐C levels have been shown to reduce the risk of ASCVD events and mortality. Statin treatment is the current first‐line therapy for lowering LDL‐C and reducing ASCVD risk. However, many patients are still unable to reach recommended LDL‐C goals on maximally tolerated statin therapy. Monoclonal antibodies that inhibit proprotein convertase subtilisin/kexin type 9, including evolocumab (previously AMG 145), dramatically lowered LDL‐C in phase 2 clinical trials when administered alone or in combination with a statin. The aim of this phase 3 study is to evaluate the efficacy of 12 weeks of subcutaneous evolocumab (vs placebo) administered every 2 weeks or every month in combination with a statin in patients with hypercholesterolemia and mixed dyslipidemia. This study will also provide comparative efficacy, safety, and tolerability data between evolocumab and ezetimibe when added to background atorvastatin therapy.  相似文献   
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