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71.
72.

Objectives

To assess 1) the association of lipid oxidation biomarkers with 10-year coronary artery disease (CAD) events and subclinical atherosclerosis, and 2) the reclassification capacity of these biomarkers over Framingham-derived CAD risk functions, in a general population.

Methods

Within the framework of the REGICOR study, 4782 individuals aged between 25 and 74 years were recruited in a population-based cohort study. Follow-up of the 4042 who met the eligibility criteria was carried out. Plasma, circulating oxidized low-density lipoprotein (oxLDL) and oxLDL antibodies (OLAB) were measured in a random sample of 2793 participants.End-points included fatal and non-fatal acute myocardial infarction (AMI) and angina. Carotid intima-media thickness (IMT) in the highest quintile and ankle-brachial index <0.9 were considered indicators of subclinical atherosclerosis.

Results

Mean age was 50.0 (13.4) years, and 52.4% were women. There were 103 CAD events (34 myocardial infarction, 43 angina, 26 coronary deaths), and 306 subclinical atherosclerosis cases. Oxidized LDL was independently associated with higher incidence of CAD events (HR = 1.70; 95% Confidence Interval: 1.02–2.84), but not with subclinical atherosclerosis. The net classification index of the Framingham-derived CAD risk function was significantly improved when ox-LDL was included (NRI = 14.67% [4.90; 24.45], P = 0.003). No associations were found between OLAB and clinical or subclinical events. The reference values for oxLDL and OLAB are also provided (percentiles).

Conclusions

OxLDL was independently associated with 10-year CAD events but not subclinical atherosclerosis in a general population, and improved the reclassification capacity of Framingham-derived CAD risk functions.  相似文献   
73.
Background: Long-term exposure to traffic-related air pollution may increase blood pressure (BP) and induce hypertension. However, evidence supporting these associations is limited, and they may be confounded by exposure to traffic noise and biased due to inappropriate control for use of BP-lowering medications.Objectives: We evaluated the associations of long-term traffic-related air pollution with BP and prevalent hypertension, adjusting for transportation noise and assessing different methodologies to control for BP-lowering medications.Methods: We measured systolic (SBP) and diastolic BP (DBP) at baseline (years 2003–2005) in 3,700 participants, 35–83 years of age, from a population-based cohort in Spain. We estimated home outdoor annual average concentrations of nitrogen dioxide (NO2) with a land-use regression model. We used multivariate linear and logistic regression.Results: A 10-μg/m3 increase in NO2 levels was associated with 1.34 mmHg (95% CI: 0.14, 2.55) higher SBP in nonmedicated individuals, after adjusting for transportation noise. Results were similar in the entire population after adjusting for medication, as commonly done, but weaker when other methods were used to account for medication use. For example, when 10 mmHg were added to the measured SBP levels of medicated participants, the association was β = 0.78 (95% CI: –0.43, 2.00). NO2 was not associated with hypertension. Associations of NO2 with SBP and DBP were stronger in participants with cardiovascular disease, and the association with SBP was stronger in those exposed to high traffic density and traffic noise levels ≥ 55 dB(A).Conclusions: We observed a positive association between long-term exposure to NO2 and SBP, after adjustment for transportation noise, which was sensitive to the methodology used to account for medication.Citation: Foraster M, Basagaña X, Aguilera I, Rivera M, Agis D, Bouso L, Deltell A, Marrugat J, Ramos R, Sunyer J, Vila J, Elosua R, Künzli N. 2014. Association of long-term exposure to traffic-related air pollution with blood pressure and hypertension in an adult population–based cohort in Spain (the REGICOR study). Environ Health Perspect 122:404–411; http://dx.doi.org/10.1289/ehp.1306497  相似文献   
74.
75.
To describe the clinical characteristics of first-ever ischemic stroke (IS) patients with prediabetes, and to compare them with diabetes mellitus (DM) and non-DM patient characteristics. Retrospective analysis of a prospective series of first-ever acute IS patients. Patients were classified as non-DM (HbA1c during admission <5.7 % and no previous evidence of 2 or more fasting glucose >126 mg/dL), prediabetes (HbA1c from 5.7 to 6.4 %), and DM (previous DM diagnosis or HbA1c ≥6.5 % independently of current blood glucose). Demographic and clinical characteristics were compared between the three groups, along with outcome data [early neurological deterioration (END), 3-month poor outcome, 3-month mortality, outcome after rtPA treatment]. No demographic differences were observed. Prediabetic patients had more arterial hypertension (p = 0.006) and higher waist circumference (p < 0.0001) than non-DM patients, and DM patients had more hypercholesterolemia (p < 0.0001), body mass index (p = 0.017), and coronary artery disease (p = 0.005) than prediabetics. There were differences in TOAST subtype distribution (p < 0.0001). There were no differences in rtPA treatment success rate between groups. Multivariate analysis adjusted by age and stroke severity showed that DM but not prediabetes is an independent factor associated with END and 3-month poor outcome. Prediabetic patients with IS exhibit an “intermediate” vascular risk factor profile between that of non-DM and DM patients. In contrast to DM patients, IS prognosis in patients with prediabetes is similar to non-DM patients.  相似文献   
76.
The diagnosis of inguinal hernia is usually clinical and it is performed with high sensitivity and specificity. Very occasionally, it may be confused with other diseases (lymphadenopathy, testicular pathology,etc). We report a rare case of a 80-year-old woman with a clinical diagnosis of hernia, which was underwent surgery and a tumor from the hernia orifice was found. After histological analysis we discovered that the misdiagnosed hernia was actually a tumor on a rudimentary testis. After radiological, gynecological and cytogenetic assessment we obtained an unexpected diagnosis: Male psheudohermaphroditism and Sertoli-Leydigtumor (SLCT) development on the testis. Diagnostic guidance for disorders of sexual development is based almost entirely on pediatric experience and very few guidelines are available for adults. Male pseudohermaphroditism is an intersex condition in which the carriers show a phenotype that includes external female genitalia, but a male genetic and gonadal sex. SLCT are sex-cord stromal tumors which develop in ovary and very rarely in the testis, representing 0.1–0.5% of ovarian tumors and less than 0.2% of testicular tumors. Thus far 24 case have been reported in the literature in which SLCT tumor has developed on testis.  相似文献   
77.
The arterial switch operation (ASO) is the preferred technique for correcting transposition of the great arteries, but translocation and reimplantation of the coronary arteries can produce myocardial ischemia. This report aims to describe the authors’ experience with exercise single-photon emission computed tomography (SPECT) used to evaluate myocardial perfusion. Exercise-rest gated-myocardial perfusion SPECT was performed for 69 patients (49 boys; median age, 9 years; 5th percentile [6.4 years] to 95th percentile [15.6 years]), 64 of whom were asymptomatic 9.98 ± 3.20 years after ASO. During exercise testing, the patients reached 9.85 ± 3.05 metabolic equivalents (METs) and a median heart rate of 160 beats per minute (bpm), 5th percentile (106 bpm) to 95th percentile (196 bpm). Whereas 61 patients (88.41 %) had normal myocardial perfusion, 2 patients (2.9 %) had reversible defects, and 6 patients (8.7 %) had fixed defects. All the patients with perioperative ischemic complications (4/4, 100 %) had myocardial perfusion defects, whereas four patients (4/65, 6.15 %) without ischemic complications had abnormal perfusion (p = 0.0005). Age at the time of surgery did not differ significantly (p = 0.234) between the patients with perfusion defects and those with normal study results. No significant difference was observed between the patients who had an A coronary pattern (left coronary artery originating from the left sinus and the right coronary artery originating from the right sinus, n = 47) and those who had a non-A coronary pattern (n = 22) (p = 1). The high rate for normality of exercise myocardial perfusion in our study suggests that myocardial perfusion gated-SPECT should be reserved for patients who have experienced perioperative ischemic complications or those with symptoms, at least during the first 10 years after the surgery.  相似文献   
78.

Objectives

The aim of this study was to determine, by using a spectrophotometer device, the colour stainability of two indirect CAD/CAM processed composites in comparison with two conventionally laboratory-processed composites after being immersed 4 weeks in staining solutions such as coffee, black tea and red wine, using distilled water as control group.

Methods

Two indirect CAD/CAM composites (Lava Ultimate and Paradigm MZ100) and two conventionally laboratory-processed composites (SR Adoro and Premise Indirect) of shade A2 were selected (160 disc samples). Colour stainability was measured after 4 weeks of immersion in three staining solutions (black tea, coffee, red wine) and distilled water. Specimen's colour was measured each week by means of a spectrophotometer (CIE L*a*b* system). Statistical analysis was carried out performing repeated ANOVA measurements and Tukey's HSD test to evaluate differences in ΔE00 measurements between groups; the interactions among composites, staining solutions and time duration were also evaluated.

Results

All materials showed significant discoloration (p < 0.01) when compared to control group. The highest ΔE00 observed was with red wine, whereas black tea showed the lowest one. Indirect laboratory-processed resin composites showed the highest colour stability compared with CAD/CAM resin blocks.

Conclusions

CAD/CAM processed composites immersed in staining solutions showed lower colour stability when compared to conventionally laboratory-processed resin composites.

Clinical significance

The demand for CAD/CAM restorations has been increasing; however, colour stainability for such material has been insufficiently studied. Moreover, this has not been performed comparing CAD/CAM processed composites versus laboratory-processed indirect composites by immersing in staining solutions for long immersion periods.  相似文献   
79.
Necrosis, as opposed to apoptosis, is recognized as a nonspecific cell death that induces tissue inflammation and is preceded by cell edema. In non-neuronal cells, the latter has been explained by defective outward pumping of Na(+) caused by metabolic depletion or by increased Na(+) influx via membrane transporters. Here we describe a novel mechanism of swelling and necrosis; namely the influx of Na(+) through oxidative stress-activated nonselective cation channels. Exposure of liver epithelial Clone 9 cells to the free-radical donors calphostin C or menadione induced the rapid activation of an approximately 16-pS nonselective cation channel (NSCC). Blockage of this conductance with flufenamic acid protected the cells against swelling, calcium overload, and necrosis. Protection was also achieved by Gd(3+), an inhibitor of stretch-activated cation channels, or by isosmotic replacement of extracellular Na(+) with N-methyl-D-glucamine. It is proposed that NSCCs, which are ubiquitous although largely inactive in healthy cells, become activated under severe oxidative stress. The ensuing influx of Na(+) initiates a positive feedback of metabolic and electrolytic disturbances leading cells to their necrotic demise.  相似文献   
80.

Introduction and objectives

New biomarkers could improve the predictive capacity of classic risk functions. The aims of this study were to determine the association between circulating levels of apolipoprotein A1 (apoA1), apolipoprotein B (apoB), albumin, and 25-OH-vitamin D and coronary events and to analyze whether these biomarkers improve the predictive capacity of the Framingham-REGICOR risk function.

Methods

A case-cohort study was designed. From an initial cohort of 5404 individuals aged 35 to 74 years with a 5-year follow-up, all the participants who had a coronary event (n = 117) and a random group of the cohort (subcohort; n = 667) were selected. Finally, 105 cases and 651 individuals representative of the cohort with an available biological sample were included. The events of interest were angina, fatal and nonfatal myocardial infarction and coronary deaths.

Results

Case participants were older, had a higher proportion of men and cardiovascular risk factors, and showed higher levels of apoB and lower levels of apoA1, apoA1/apoB ratio, 25-OH-vitamin D and albumin than the subcohort. In multivariate analyses, plasma albumin concentration was the only biomarker independently associated with coronary events (HR, 0.73; P = .002). The inclusion of albumin in the risk function properly reclassified a significant proportion of individuals, especially in the intermediate risk group (net reclassification improvement, 32.3; P = .048).

Conclusions

Plasma albumin levels are inversely associated with coronary risk and improve the predictive capacity of classic risk functions.  相似文献   
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