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Cadmium Accumulation in Tomato Cultivars and Its Effect on Expression of Metal Transport-Related Genes 总被引:2,自引:0,他引:2
Sara Hartke Adriano Alves da Silva Marcelo Gravina de Moraes 《Bulletin of environmental contamination and toxicology》2013,90(2):227-232
Cadmium (Cd) content was quantified in the shoot of six tomato cultivars and the Cd effect on the expression of LeNRAMP3, LeFER, LeIRT1 and LeNRAMP1 was evaluated. The six tomato cultivars accumulated high Cd concentrations and were able to transport Cd to the fruits. Among the evaluated genes, the Cd-induced level of LeFER expression appeared to provide an evidence regarding the capacity of foliar Cd accumulation in tomato. The results indicate that tomato represents a possible pathway for Cd entry into the food chain and an attractive model organism for the elucidation of the mechanisms involved in Cd accumulation. 相似文献
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Milena Baptista Bueno Regina Mara Fisberg Priscila Maximino Guilherme de Pádua Rodrigues Mauro Fisberg 《Nutrition (Burbank, Los Angeles County, Calif.)》2013,29(2):405-410
ObjectiveTo estimate the nutritional risk in children 2 to 6 y old.MethodsThe sample consisted of 3058 children enrolled in public and private schools in nine Brazilian cities. The assessment of nutrient intake was based on 1-d data combining direct individual weighing of foods and a food diary. A second evaluation of food consumption was conducted in a subsample to estimate the usual intake.ResultsThere was low prevalence of inadequate intake of vitamin B6 (<0.001%), riboflavin (<0.001%), niacin (<0.001%), thiamin (<0.001%), folate (<0.001%), phosphorus (<0.1%), magnesium (<0.1%), iron (<0.5%), copper (<0.001%), zinc (<0.5%), and selenium (<0.001%). However, 22% of children younger than 4 y and 5% of children older than 4 y consumed fiber quantities larger than the adequate intake. Approximately 30% of the sample consumed more saturated fat than recommended. The prevalence of inadequate vitamin E intake ranged from 15% to 29%. More than 90% of the children had an inadequate vitamin D intake. In children older than 4 y, the prevalence of inadequate calcium intake was approximately 45%. Sodium intake was higher than the upper intake level in 90% of children younger than 4 y and 73% of children older than 4 y.ConclusionsThe prevalence of inadequate dietary intake was low for most nutrients. However, fiber, calcium, and vitamin D and E intakes were lower than recommended. Moreover, children consumed large amounts of sodium and saturated fat. 相似文献
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Rodrigo Vitório Ellen Lirani-Silva Fabio Augusto Barbieri Vivian Raile Florindo Stella Lilian Teresa Bucken Gobbi 《Gait & posture》2013,37(2):330-334
The purpose of the current study was to investigate the role of visual information on gait control in people with Parkinson's disease as they crossed over obstacles. Twelve healthy individuals, and 12 patients with mild to moderate Parkinson's disease, walked at their preferred speeds along a walkway and stepped over obstacles of varying heights (ankle height or half-knee height), under three visual sampling conditions: dynamic (normal lighting), static (static visual samples, similar to stroboscopic lighting), and voluntary visual sampling. Subjects wore liquid crystal glasses for visual manipulation. In the static visual sampling condition only, the patients with Parkinson's disease made contact with the obstacle more often than did the control subjects. In the successful trials, the patients increased their crossing step width in the static visual sampling condition as compared to the dynamic and voluntary visual sampling conditions; the control group maintained the same step width for all visual sampling conditions. The patients showed lower horizontal mean velocity values during obstacle crossing than did the controls. The patients with Parkinson's disease were more dependent on optic flow information for successful task and postural stability than were the control subjects. Bradykinesia influenced obstacle crossing in the patients with Parkinson's disease. 相似文献
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Ana Maria Betim Paes Leme Vera Maria Cury Salemi Robert G. Weiss Jose Rodrigues Parga Bárbara Maria Ianni Charles Mady Roberto Kalil-Filho 《Journal of cardiac failure》2013,19(7):454-460
BackgroundThe influence of exercise on cardiac metabolic response in patients with Chagas disease is incompletely understood.Methods and ResultsChanges in cardiac energetic metabolism were investigated in Chagas disease patients before and during isometric handgrip exercise with 31P magnetic resonance spectroscopy (MRS). Twenty-eight patients (10 with systolic dysfunction: group I; 10 with normal systolic function and electrocardiogram (ECG) abnormalities: group II; and 8 asymptomatic without ECG abnormalities: group III) and 8 healthy control subjects (group C) were evaluated by electrocardiogram, echocardiogram, functional tests for coronary artery disease, and image-selected localized cardiac 31P-MRS. The myocardial phosphocreatine to [β-phosphate]adenosine triphosphate ratio (PCr/β-ATP) was measured at rest and during isometric handgrip exercise. Exercise testing or 99mTc–sestamibi scintigraphy were negative for myocardial ischemia in all individuals. At rest, cardiac PCr/β-ATP was decreased in all Chagas groups (1.23 ± 0.37) versus group C (1.88 ± 0.08; P < .001) and was lower in group I (0.89 ± 0.24) versus groups II (1.44 ± 0.23) and III (1.40 ± 0.37; P < .001). There was no stress-induced change in cardiac PCr/β-ATP (1.88 ± 0.08 at rest vs 1.89 ± 0.08 during exercise; P = NS) in group C. Mean cardiac PCr/β-ATP was 0.89 ± 0.24 and 0.56 ± 0.21 at rest and during exercise, respectively, in group I (37% decrease; P < .001). In group II, PCr/β-ATP was 1.44 ± 0.23 at rest and 0.97 ± 0.37 during exercise (33% decrease; P < .001). In group III, PCr/β-ATP was 1.40 ± 0.37 at rest and 0.60 ± 0.19 during exercise (57% decrease; P < .001).ConclusionsMyocardial high-energy phosphates are reduced at rest in Chagas heart disease patients, and the reduction is greater in patients with left ventricular dysfunction. Regardless of left ventricular function, Chagas patients exhibit an exercise-induced decline in cardiac high-energy phosphates consistent with myocardial ischemia, suggesting the possibility that this metabolic approach may offer a tool to probe new interventions in Chagas disease patients. 相似文献