10 research outputs found

    Nitrate in groundwater in a recharge area of Guarany aquifer in Brazil.

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    The region of Ribeirão Preto City located in São Paulo State, southeastern Brazil, is an important sugarcane, soybean and corn producing area. This region is also an important recharge area (Espraiado) for groundwater of the Guarany aquifer, a water supply source for the city and region. It has an intercontinental extension that comprises areas of eight Brazilian states, as well as significant portions of other South American countries like Argentina, Uruguay, and Paraguay, with a total area of approximately 1,200,000 Km2. Due to the high permeability of some soils present in this region, the high mobility of the herbicides and fertilizers applied, and being a recharge area, it is important to investigate the potential transport of applied fertilizers to underlying aquifer. The cultivation sugar cane in this area demands the frequent use of nitrogen as fertilizer. This research was conducted to characterize the potential contamination of groundwater with nitrogen in the recharge area of groundwater. Seven groundwater sample points were selected in the Espraiado stream watershed, during the years of 2005 and 2006. Samples were collected during the months of March, July, and December of each year. Three replications were collected at each site. Groundwater was also collected during the same months from county groundwater wells located throughout the city. The following six wells were studied: Central, Palmares, Portinari, Recreio Internacional, São Sebastião, and São José. Nitrate water samples were analyzed by Cadmium Reduction Method. No significant amount of nitrate was found in the recharge, agricultural, area. However, nitrate levels were detected at concentrations higher than the Maximum Concentration Level (MCL) of 10mg/L in downtown, urban, well located away from agricultural sites with no history of fertilizer or nitrogen application

    Sugarcane herbicide leaching risk evaluation in Guarany Aquifer.

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    he region of Ribeirão Preto, São Paulo State, Brazil, is located over recharge area of the Guarany aquifer, the most important source of groundwater in the South Central region of the country. This region is also the most important sugarcane producing area of the country which produces a large amount of the ethanol. This study was conducted to determine the potential risk of herbicide groundwater contamination. The leaching risk potential of herbicides to groundwater was conducted using the weather simulator ?Weather Generator? (WGEN) coupled with the model ?Chemical Movement Trough Layered Soils? (CMLS94). The following herbicides were evaluated in clayey and sandy soils (Typic Haplorthox and Typic Quartzipsamment soils) found in the region: ametryn (N-ethyl-N\'-(1- methylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine), atrazine (6-chloro-N-ethyl-N\'-(1-methylethyl)-1,3,5-triazine- 2,4-diamine), clomazone (2-[(2-chlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone), diuron (3,4-dichlorophenyl)- N,N-dimethylurea), halosulfuron (3-chloro-5-[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl], hexazinone (3- cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4 (1H,3H)-dione), imazapic ((±)-2-[4,5-dihydro-4-methyl-4- (1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-methyl-3-pyridinecarboxylic acid), imazapyr ((±)-2-[4,5-dihydro-4-methyl- 4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-pyridinecarboxylic acid), MCPA (4-chloro-2-methylphenoxy)acetic acid), metribuzin (4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one), MSMA (Amonosodium salt of MAA), paraquat (1,1\'-dimethyl-4,4\'-bipyridinium ion), pendimethalin (N-(1-ethylpropyl)-3,4-dimethyl-2,6- dinitrobenzenamine), picloram (4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid), simazine (6-chloro-N,N\'-diethyl- 1,3,5-triazine-2,4-diamine), sulfentrazone [N-[2,4-dichloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H- 1,2,4-triazol-1-yl]phenyl]methanesulfonamide], and tebuthiuron [N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N\'- dimethylurea]. Results obtained by our simulation study have shown that the herbicides picloram, tebuthiuron, and metribuzin have the highest leaching potential, in either sandy or clayey soils, with picloram reaching the root zone of sugarcane at 0.6m in less than 150 days

    Cardiovascular Events Associated With Androgen Deprivation Therapy In Patients With Prostate Cancer: A Systematic Review And Meta-analysis

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    Context: A recently published meta-analysis of randomized clinical trials (RCT) showed that androgen deprivation therapy (ADT) did not significantly increase cardiovascular mortality in prostate cancer patients. However, cardiovascular morbidity, which can impact quality of life, was not evaluated.Objective: To evaluate the risk of cardiovascular morbidity associated with ADT in patients with prostate cancer.Methods: We conducted a literature search from January 1960 to June 2012. RCT and large cohort studies that evaluated first-line endocrine therapy and ADT longer than 6 months were screened for inclusion.Results: In total, 126,898 patients were included in four cohort studies, and 10,760 patients were included in nine RCTs. Analysis of the RCTs showed no differences in the development of acute myocardial infarction (AMI) (OR 1.23; 95 % CI 0.92–1.64; I2: 0 %) among the patients receiving ADT or not. The analysis of randomized studies that reported other nonfatal cardiovascular events demonstrated a significant increase in such events in the group receiving ADT (OR 1.55; 95 % CI 1.09–2.20; I2: 0 %). When the large cohort studies were included in the analysis, an increased risk of AMI among men with ADT was found (OR 2.01, 95 % CI 1.90–2.13; I2: 91,3 %).Conclusion: The use of ADT in prostate cancer patients corresponded with a significant increase in cardiovascular morbidity associated with AMI and with nonfatal events. Therefore, ADT is linked to a significant negative impact on quality of life. Periodic cardiovascular evaluation is required for these patients

    Nitrate in groundwater in Ribeirão Preto city area in Brazil.

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    The region of Ribeirão Preto City, southeastern Brazil, is an important sugar cane and recharge area for groundwater of the Guarany aquifer. This research was conducted to evaluate the potential contamination of groundwater with nitrates in the area and in surrounding municipal wells. No significant amount of nitrate was found in the recharge agricultural area. However, nitrate levels were detected at concentrations higher than the Maximum Concentration Level (MCL) of 6.0 mg/L in a downtown, urban, well located away from agriculture, which had no history of nitrogen application, reaching values higher than the maximum risk coefficient for infants (RC) of 1.0

    ECPPA: Randomised trial of low dose aspirin for the prevention of maternal and fetal complications in high risk pregnant women

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    Objective To determine the effectiveness of low dose aspirin in women at high risk of adverse outcomes associated with pre-eclampsia.Design A collaborative randomised trial comparing the effects of low dose aspirin (60 mg) with placebo on pre-eclampsia and other materno-fetal complications associated with hypertension.Setting Twelve teaching maternity hospitals and 182 obstetricians' offices in Brazil.Subjects One thousand and nine women considered to be at high risk for the development of preeclampsia, or its complications, entered the study between 12 and 32 weeks of gestation. They were randomly allocated to receive aspirin (498 women) or placebo (511 women) until delivery, and follow up was obtained for 96%.Results There were no significant differences between the treatment groups in the incidence of proteinuric pre-eclampsia (6.7% aspirin-allocated compared with 6.0% placebo-allocated women), of preterm delivery (22.3% compared with 26.1%), of intrauterine growth retardation (8.5% compared with 10.1%), or of stillbirth and neonatal death (7.3% compared with 6.0%), nor were there significant differences in the incidence of proteinuric pre-eclampsia in any subgroup of women studied, including those who had systolic blood pressures of 120 mmHg or above at entry (8.5% compared with 7.3%) or those who were chronically hypertensive (10.0% compared with 7.1%). Aspirin was not associated with a significant excess of maternal or fetal bleeding.Conclusion The results of this study do not support the routine prophylactic administration of low dose aspirin in pregnancy to any category of high risk women (even those who have chronic hypertension or who are considered to be especially liable to early onset pre-eclampsia).ESCOLA PAULISTA MED,DEPT MED,MED CLIN D,RUA BOTUCATU 740,BR-04023900 SAO PAULO,BRAZILESCOLA PAULISTA MED,DEPT MED,MED CLIN D,RUA BOTUCATU 740,BR-04023900 SAO PAULO,BRAZILWeb of Scienc
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