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51.

Introduction and objectives

Multidetector computed tomography (MDCT) has been demonstrated as a feasible alternative to invasive coronary angiography (ICA). However, contradictory results have been reported regarding the effect of coronary artery calcium score (CS) on the diagnostic accuracy of MDCT. Our aim was to assess the agreement of MDCT and ICA and to evaluate the influence of CS on this agreement.

Methods

We enrolled 266 consecutive patients who underwent evaluation with 64-slice MDCT and ICA. Standard CS software tools were used to calculate the Agatston score. Stenosis was qualitatively classified as mild, moderate, or severe by 1 blinded observer and the results were compared with those of ICA, which was used as the gold standard.

Results

The mean age of the patients was 65.4 ± 11.2 years, and 188 patients (70.3%) were men. A total of 484 segments with coronary stenosis ≥ mild were qualitatively evaluated and quantified with MDCT. Noninvasive measurements were concordant with ICA in 402 stenoses (83.05%; Kappa, 0.684), with no significant differences between vessels and with no statistically significant influence of CS on this agreement (OR, 0.93; 95%CI, 0.76-1.09; P = .21). Multidetector computed tomography had high sensitivity, specificity, positive predictive value, and negative predictive value on a per-segment, per-vessel, and per-patient basis.

Conclusions

Non-ICA using MDCT showed good agreement with ICA in the qualitative quantification coronary stenosis and CS had no significant impact on this agreement.Full English text available from: www.revespcardiol.org/en  相似文献   
52.
Venezuela had the highest number of human malaria cases in Latin American before 1936. During 1891–1920, malaria was endemic to >600,000 km2 of this country; malaria death rates led to major population decreases during 1891–1920. No pathogen, including the influenza virus that caused the 1918 pandemic, caused more deaths than malaria during 1905–1945. Early reports of malaria eradication in Venezuela helped spark the world’s interest in global eradication. We describe early approaches to malaria epidemiology in Venezuela and how this country developed an efficient control program and an approach to eradication. Arnoldo Gabaldón was a key policy maker during this development process. He directed malaria control in Venezuela from the late 1930s to the end of the 1970s and contributed to malaria program planning of the World Health Organization. We discuss how his efforts helped reduce the incidence of malaria in Venezuela and how his approach diverged from World Health Organization guidelines.  相似文献   
53.

Objective

To assess whether a cold pressor test (CPT) could help identify patients at a high risk of cardiovascular events in a population without known coronary artery disease (CAD) with a normal myocardial perfusion scintigraphy (MPS).

Methods

Our population consisted of 870 patients with a mean age of 59.3 years with several CAD risk factors, having been referred for an MPS. The CPT was performed between the third day and fifth day after the MPS.

Results

The CPT was positive in 38.2% of the patients. After a mean 40-month follow-up, the patients were contacted to check for cardiac death, non-fatal myocardial infarction, and myocardial revascularization procedures. The event-free survival rates were 98.1% and 90.4% after a negative or positive CPT, respectively (p = 0.0001). The positive CPT group exhibited a fourfold increased risk of CV events. All CV events in the negative CPT group occurred after a 30-month follow-up. The risk of CV events was 4.5 times higher in diabetic patients.

Conclusion

A positive CPT in patients with a negative MPS could help identify a subgroup of patients at a higher risk of developing symptomatic CAD.

Practice implications

Our results suggest that after a normal post-exercise MPS, patients should undergo a CPT.  相似文献   
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55.

Purpose

It has been suggested that subjective measures of oral health are influenced by both individual and contextual characteristics. This study assessed the relationship between neighborhood and individual social networks and child oral health-related quality of life (COHRQoL).

Methods

This study followed a cross-sectional design using a multistage sample of 478 children aged 1–5 years old. Caregivers completed the Brazilian version of the Early Childhood Oral Health Impact Scale (ECOHIS) and answered questions related to socioeconomic status and social network. The dental examination provided information on the prevalence of dental caries, dental trauma, and occlusion. Contextual social determinants included the presence of cultural community centers and of workers’ association in the neighborhood. Data analysis considered the total ECOHIS scores as the outcome and neighborhood/individual social networks as the independent variables. A multilevel Poisson regression model was used to investigate the association among individual and contextual characteristics and COHRQoL.

Results

Total ECOHIS scores ranged from 0 to 41 (possible range 0–52). The mean ECOHIS score was low (mean = 1.8, SD = 3.9), and the functional domain presented the highest mean impact on COHRQoL (mean = 0.5, SD = 1.4). Following adjusted analysis, low household income, visiting a neighbor less than once a month, the presence of anterior open bite, dental trauma, and dental caries were identified as individual determinants of negative impact on a child’s quality of life. These variables remained associated with the outcome even after adding the contextual-level variables in the model. At the contextual level, the presence of community cultural centers was associated with overall mean ECOHIS score; higher impacts on COHRQoL were observed in those living in neighborhoods without cultural community centers.

Conclusion

There is a significant association between individual and contextual social determinants and COHRQoL; unfavorable social conditions and poor socioeconomic status have a negative impact on caregiver reports of children’s oral health-related quality of life.  相似文献   
56.
This study describes the insecticidal activity of a novel Bacillus thuringiensis Cry-related protein with a deduced 799 amino acid sequence (~89 kDa) and ~19% pairwise identity to the 95-kDa-aphidicidal protein (sequence number 204) from patent US 8318900 and ~40% pairwise identity to the cancer cell killing Cry proteins (parasporins Cry41Ab1 and Cry41Aa1), respectively. This novel Cry-related protein contained the five conserved amino acid blocks and the three conserved domains commonly found in 3-domain Cry proteins. The protein exhibited toxic activity against the green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae) with the lowest mean lethal concentration (LC50 = 32.7 μg/mL) reported to date for a given Cry protein and this insect species, whereas it had no lethal toxicity against the Lepidoptera of the family Noctuidae Helicoverpa armigera (Hübner), Mamestra brassicae (L.), Spodoptera exigua (Hübner), S. frugiperda (J.E. Smith) and S. littoralis (Boisduval), at concentrations as high as ~3.5 μg/cm2. This novel Cry-related protein may become a promising environmentally friendly tool for the biological control of M. persicae and possibly also for other sap sucking insect pests.  相似文献   
57.
58.
Nitric Oxide in the Pathogenesis of Cardiac Disease   总被引:3,自引:0,他引:3  
Endothelial dysfunction is characterized by a vasoconstrictive and prothrombotic state in the vasculature; it plays a role in all stages of cardiac disease and is a significant independent predictor of cardiovascular outcomes. Nitric oxide (NO) performs multiple biologic activities in the endothelium, including vasodilation and antithrombotic actions. Reduced NO bioactivity is a major component of endothelial dysfunction. Impaired NO bioactivity is an important factor in the pathogenesis of atherosclerosis and in the metabolic syndrome. The functions of NO bioactivity in the heart go well beyond those in the endothelium, as all 3 NO synthase (NOS) isoforms—endothelial NOS, neuronal NOS, and inducible NOS—are expressed in cardiac myocytes and mediate systolic, diastolic, and chronotropic cardiac functions. Impairment of NO bioactivity is a pathogenic factor in various forms of cardiac disease. Although these findings support the potential use of NO-targeted therapies for treatment of cardiac disease, the complexities of the biologic actions of NO in the vasculature and heart are such that development of therapies is still largely in the preliminary stages.  相似文献   
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