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2.
Bull Environ Contam Toxicol ; 86(1): 18-22, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21165598

ABSTRACT

A method for the determination of pesticide residues in water and sediment was developed using the QuEChERS method followed by gas chromatography--mass spectrometry. The method was validated in terms of accuracy, specificity, linearity, detection and quantification limits. The recovery percentages obtained for the pesticides in water at different concentrations ranged from 63 to 116%, with relative standard deviations below 12%. The corresponding results from the sediment ranged from 48 to 115% with relative standard deviations below 16%. The limits of detection for the pesticides in water and sediment were below 0.003 mg L⁻¹ and 0.02 mg kg⁻¹, respectively.


Subject(s)
Chemistry Techniques, Analytical/methods , Gas Chromatography-Mass Spectrometry/methods , Geologic Sediments/chemistry , Pesticide Residues/analysis , Water Pollutants, Chemical/analysis , Atrazine/analysis , Atrazine/chemistry , Endosulfan/analysis , Endosulfan/chemistry , Fresh Water/chemistry , Pesticide Residues/chemistry , Pyrazoles/analysis , Pyrazoles/chemistry , Seawater/chemistry , Water , Water Pollutants, Chemical/chemistry
3.
J Hazard Mater ; 182(1-3): 325-30, 2010 Oct 15.
Article in English | MEDLINE | ID: mdl-20599322

ABSTRACT

The content of Al, Ba, Ca, Cr, Cu, Fe, Ni, P, Zn, Cd and Pb was determined in textile material samples after microwave-assisted decomposition in a cavity oven and extraction with an artificial sweat solution. Radial viewing inductively coupled plasma optical emission spectrometry (ICP OES) was the main detection technique, but Cd and Pb were determined by thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) to increase the sensitivity. Principal components analysis (PCA) was applied to the data sets to characterize the samples with respect to their geographic origin and color difference. The PCA for Brazilian single-color samples showed separation, with one group consisting of blue and green textiles and another with all the other materials evaluated. The geographic origin study showed a clear separation between Brazilian and Chinese textiles. The metals amount extracted with sweat extractable solution were lower than limits values pointed by the International Testing and Certification System for Textiles, Oko Tex Standard 100, in the all considered classes. Recoveries varied from 85 to 112% for additions ranging from 3.0 to 25 mg kg(-1) for Ca and from 0.3 to 7.0 mg kg(-1) for all other analytes through the microwave-assisted decomposition procedure.


Subject(s)
Minerals/analysis , Spectrophotometry, Atomic/methods , Textiles/analysis , Principal Component Analysis
4.
Braz J Med Biol Res ; 41(6): 512-8, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18622495

ABSTRACT

Our aim was to determine the frequencies of the angiotensin-converting enzyme (ACE) gene alleles D and I and any associations to cardiovascular risk factors in a population sample from Rio de Janeiro, Brazil. Eighty-four adults were selected consecutively during a 6-month period from a cohort subgroup of a previous large cross-sectional survey in Rio de Janeiro. Anthropometric data and blood pressure measurements, echocardiogram, albuminuria, glycemia, lipid profile, and ACE genotype and serum enzyme activity were determined. The frequency of the ACE*D and I alleles in the population under study, determined by PCR, was 0.59 and 0.41, respectively, and the frequencies of the DD, DI, and II genotypes were 0.33, 0.51, and 0.16, respectively. No association between hypertension and genotype was detected using the Kruskal-Wallis method. Mean plasma ACE activity (U/mL) in the DD (N = 28), DI (N = 45) and II (N = 13) groups was 43 (in males) and 52 (in females), 37 and 39, and 22 and 27, respectively; mean microalbuminuria (mg/dL) was 1.41 and 1.6, 0.85 and 0.9, and 0.6 and 0.63, respectively; mean HDL cholesterol (mg/dL) was 40 and 43, 37 and 45, and 41 and 49, respectively, and mean glucose (mg/dL) was 93 and 108, 107 and 98, and 85 and 124, respectively. A high level of ACE activity and albuminuria, and a low level of HDL cholesterol and glucose, were found to be associated with the DD genotype. Finally, the II genotype was found to be associated with variables related to glucose intolerance.


Subject(s)
Hypertension/enzymology , Hypertension/genetics , Lipids/blood , Peptidyl-Dipeptidase A/genetics , Polymorphism, Genetic/genetics , Albuminuria/enzymology , Albuminuria/genetics , Blood Glucose/genetics , Body Mass Index , Brazil , Cohort Studies , Cross-Sectional Studies , Female , Genotype , Humans , Hypertension/blood , Male , Middle Aged , Phenotype , Polymerase Chain Reaction , Risk Factors
5.
Braz. j. med. biol. res ; 41(6): 512-518, June 2008. tab
Article in English | LILACS | ID: lil-485844

ABSTRACT

Our aim was to determine the frequencies of the angiotensin-converting enzyme (ACE) gene alleles D and I and any associations to cardiovascular risk factors in a population sample from Rio de Janeiro, Brazil. Eighty-four adults were selected consecutively during a 6-month period from a cohort subgroup of a previous large cross-sectional survey in Rio de Janeiro. Anthropometric data and blood pressure measurements, echocardiogram, albuminuria, glycemia, lipid profile, and ACE genotype and serum enzyme activity were determined. The frequency of the ACE*D and I alleles in the population under study, determined by PCR, was 0.59 and 0.41, respectively, and the frequencies of the DD, DI, and II genotypes were 0.33, 0.51, and 0.16, respectively. No association between hypertension and genotype was detected using the Kruskal-Wallis method. Mean plasma ACE activity (U/mL) in the DD (N = 28), DI (N = 45) and II (N = 13) groups was 43 (in males) and 52 (in females), 37 and 39, and 22 and 27, respectively; mean microalbuminuria (mg/dL) was 1.41 and 1.6, 0.85 and 0.9, and 0.6 and 0.63, respectively; mean HDL cholesterol (mg/dL) was 40 and 43, 37 and 45, and 41 and 49, respectively, and mean glucose (mg/dL) was 93 and 108, 107 and 98, and 85 and 124, respectively. A high level of ACE activity and albuminuria, and a low level of HDL cholesterol and glucose, were found to be associated with the DD genotype. Finally, the II genotype was found to be associated with variables related to glucose intolerance.


Subject(s)
Female , Humans , Male , Middle Aged , Hypertension/enzymology , Hypertension/genetics , Lipids/blood , Peptidyl-Dipeptidase A/genetics , Polymorphism, Genetic/genetics , Albuminuria/enzymology , Albuminuria/genetics , Body Mass Index , Brazil , Blood Glucose/genetics , Cohort Studies , Cross-Sectional Studies , Genotype , Hypertension/blood , Phenotype , Polymerase Chain Reaction , Risk Factors
6.
Chemosphere ; 68(3): 537-45, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17280702

ABSTRACT

In this work Paspalum notatum root material was used to elucidate the influence of acid leaching pre-treatment and of sorption medium on metal adsorption. Ground P. notatum root was leached with 0.14M HNO(3). Leached root material (LRM) and non-leached root material (NLRM) were employed to flow sorption of Ni(II), Cu(II), Al(III) and Fe(III) in 0.5M CH(3)COONH(4) medium at pH 6.5. For LRM the sorption was also studied in 0.5M KNO(3) medium. The acid pre-treatment increased the sorption capacity (SC) for all ions studied. For the KNO(3) medium, Cu(II) and Fe(III) sorption was higher than in CH(3)COONH(4) and the type of the Ni(II) isotherm's model changed. The Freundlich model was the most representative isotherm model to describe metallic ions sorption. The (1)H NMR spectra showed differences between LRM and NLRM and the acid-basic potentiometric titration elucidated that acid-leaching procedure affected the root material sorption sites once only two predominant sorption sites were found for LRM (phenolic and amine, both able cations sorption) and five sorption sites (two carboxylic, amine and two phenolic) were founded for NLRM.


Subject(s)
Aluminum/chemistry , Copper/chemistry , Iron/chemistry , Nickel/chemistry , Plant Roots/chemistry , Adsorption , Hydrogen-Ion Concentration , Kinetics , Nitrates , Paspalum , Plant Roots/metabolism , Potassium Compounds , Soil Pollutants
7.
Talanta ; 55(4): 847-54, 2001 Oct 31.
Article in English | MEDLINE | ID: mdl-18968433

ABSTRACT

Tungsten coil atomizer atomic absorption spectrometry (TCAAS) was used to determine Dy and Eu in acid-digested faeces of sheep. These elements were used as markers in animal nutrition studies. Samples were dried, ground and decomposed using a nitric-perchloric acid mixture. The accuracy of the developed method was evaluated by graphite furnace atomic absorption spectrometry (GFAAS). The results obtained for Eu were validated at a 95% confidence level using a paired t-test. The results for Dy were not validated owing to memory effects caused by carbide formation into the graphite tube. This effect did not occur for Eu. The detection limits for Dy and Eu were 6.9 and 2.1 mug l(-1) by TCAAS, and 2.2 and 5.2 mug l(-1) by GFAAS, respectively. Relative standard deviations (R.S.D.; n=5) were 0.7-3.8 and 0.8-5.6% for Dy and Eu by TCAAS and 0.8-5.4 and 0.3-3.8% for Dy and Eu by GFAAS, respectively. The lifetime of the tungsten coil was around 200 heating cycles, which is three-fold higher than graphite tube lifetime. The proposed method can be used to determine the passage rate of feed through animal digestive tract.

8.
Fresenius J Anal Chem ; 371(4): 536-40, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11760066

ABSTRACT

The residual carbon content of a variety of bovine-derived samples and forage was determined by inductively coupled plasma optical emission spectrometry with radial view configuration (ICP-OES) after microwave-assisted digestion under high pressure in a closed vessel. The original carbon concentration in the samples was determined by elemental analysis. The highest amount of original carbon content (64%) was found in viscera. After digestion, up to 75% of it was destroyed. Viscera presented the highest ether extract and blood exhibited a high crude protein content of up to 99%. The efficiency in destroying the organic matter in biological materials seemed to be related to their fat content and showed no significant difficulty for protein-rich samples. The correlation coefficient between the fat content of the samples and the residual carbon after acid decomposition was 0.9173 indicating a fair fit. However, no correlation was observed between % RC and the protein content.


Subject(s)
Carbon/analysis , Fats/analysis , Microwaves , Proteins/analysis , Animals , Cattle , Ether/chemistry
9.
Analyst ; 125(10): 1861-4, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11070555

ABSTRACT

A single vessel procedure using a focused microwave oven is proposed for biological sample preparation with nitric acid vapour under atmospheric pressure. A laboratory-made PTFE support vessel equipped with four cups that received the samples was adapted to fit on the microwave glass vessel. Biological samples (30 mg) were directly weighed into these PTFE cups followed by the addition of 150 microliters of water or H2O2. The mixture was exposed to acid vapour stemming from 15 ml of concentrated HNO3 placed in the bottom of the glass vessel. The acid vapour was formed at 115 degrees C and brought about the Co and Fe extraction in 10 and 60 min, respectively. The resulting suspension was diluted with 0.14 mol l-1 HNO3 to a final volume of 1.0 ml, shaken and centrifuged. The supernatant was analysed by electrothermal atomic absorption spectrometry (ETAAS) by placing the cups directly in the autosampler of the spectrometer. This system minimised contamination, and reagent and time consumption and was suitable for Co and Fe determination in biological materials. The accuracy of the proposed method was assessed by using certified reference materials and by comparison with the closed vessel microwave as a comparative technique. Cobalt and Fe recovery was around 82-99%. As an additional advantage, up to 6 samples can be simultaneously prepared in each vessel, thereby improving the sample throughput from 6 to 24, when a 6-cavity focused microwave is used.


Subject(s)
Cobalt/analysis , Iron/analysis , Animals , Cattle , Liver/chemistry , Microwaves , Plants/chemistry , Spectrophotometry, Atomic/methods
10.
Talanta ; 51(1): 1-6, 2000 Jan 24.
Article in English | MEDLINE | ID: mdl-18967830

ABSTRACT

Studies involving the kinetic reaction between vanillin and condensed tannins were developed using a flow injection system with spectrophotometric determination. A solution of the monomeric compound (-)-epicatechin was used as the analytical standard. This compound was chosen due to its structure, which is similar to a polymeric unit of the condensed tannin present in plants. The results indicated that the vanillin-condensed tannin reaction is time dependent and affected by the degree of polymerization of the condensed tannin. The flow system allowed (-)-epicatechin to be used without overestimating the content of the tannin present in the forage legume, guandu (Cajanus cajan (L.) Millsp.), studied. A relative standard deviation (R.S.D.) of <1% was found for a 4 h period work and allowed the determination of about 60 samples h(-1) with a detection limit of 1.05 mg l(-1) for condensed tannin. When compared to the manual vanillin procedure, the proposed approach can be used with various advantages.

11.
Talanta ; 53(2): 331-6, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-18968118

ABSTRACT

A sequential injection system was proposed to accomplish the potentiometric determination of urea. This procedure used an ammonium tubular selective electrode to assess ammonium concentration produced by enzymatic hydrolysis of urea from Jack bean meal (Canavalia ensiformis DC) crude extract. A gaseous diffusion device was coupled to the flow set-up allowing on-line sampling and suitable selectivity for determinations. A detection limit of 6.0x10(-4) mol urea l(-1), a relative standard deviation of 1.9% (n=10) and a sampling rate of 20 samples h(-1) were observed when 172 Sumner units (SU) of urease and 900 mul of sample were used. Results agreeing with a comparative method were obtained by the proposed procedure and the use of the crude extract solution combined with the sequential injection approach improved the performance, producing reproducible results and low costs in comparison with procedures using commercial enzymes.

12.
Talanta ; 47(3): 613-23, 1998 Nov.
Article in English | MEDLINE | ID: mdl-18967363

ABSTRACT

A method for ytterbium determination in animal faeces by tungsten coil electrothermal atomic absorption spectrometry (TCAAS) was developed. Faeces were dry-ashed in a muffle furnace, the ashes were treated with hydrochloric acid, and 10 mul of sample solution were delivered into 150-W tungsten coil atomizer. A matrix-matching procedure employing a 66-s heating program proved to be efficient for obtaining accurate results. Characteristic mass and detection limit were 7.1 pg and 0.35 mug g(-1) Yb, respectively. The tungsten coil atomizer lifetime exceeded 300 firings with digested solutions and R.S.D. of measurements was 1.9% after ten consecutive injections of 10.0 mug l(-1) Yb. Accuracy of the proposed method was assessed by employing a graphite furnace atomic absorption spectrometric procedure. Application of the paired t-test did not reveal any significant difference for ytterbium contents determined by both methods at 95% confidence level. It was demonstrated that the proposed procedure can successfully be used for evaluation of kinetic passage rate of feed through digestive tract of animals.

13.
J Pediatr (Rio J) ; 72(5): 335-40, 1996.
Article in Portuguese | MEDLINE | ID: mdl-14688922

ABSTRACT

Lymphangioma is a common pathology in children, however intra-abdominal cystic lymphangioma is rare. Morphology and clinical symptoms are variable and can be mixed up with other etiology. Ultrasound can make the diagnosis in the majority of the cases. Surgery is the best choice of treatment and prognosis is in general good. Authors present eight cases in a period of fifteen years, all of them treated surgically. Results were good in seven cases. One late death was observed.

14.
Cad Saude Publica ; 11(3): 389-94, 1995.
Article in Portuguese | MEDLINE | ID: mdl-12973619

ABSTRACT

The aim of this paper (the second of two) is to present the basic results of a cross-sectional study on arterial hypertension in adults in Ilha do Governador (a district of the city of Rio de Janeiro, Brazil), with a representative sample of the population, stratified by the census tracts' mean household income (low, median, and high). Overall, prevalence of uncontrolled hypertension in Ilha do Governador was 16.1% (C.I. of 95%: 13.4 to 18.9%), and with the inclusion of controlled hypertensive individuals this figure rose to 24.9% (C I. of 95%: 21.7 to 28.7%). Under both criteria (whether including controlled hypertensive individuals or not), higher prevalences were from low-income strata, while lower ones were from the high-income strata. However, it was only possible to reject the hypothesis of strata homogeneity of prevalences (including controlled hypertensives), and even then at a 10% level of significance, when the confounding effect of age was adjusted. Proportionally, women with hypertension appear to control their blood pressure levels better than men in all age brackets.

15.
Cad Saude Publica ; 11(2): 187-201, 1995.
Article in Portuguese | MEDLINE | ID: mdl-14528326

ABSTRACT

The aim of this paper (first of a series of two) is to present the main methodological aspects used in a cross-sectional study whose proposals were to establish the prevalence of arterial hypertension in adults in Ilha do Governador (a district of the city of Rio de Janeiro, Brazil), and to examine its relationship to other risk factors, including those for cardiovascular diseases, so as to establish its control status. Sampling design (of clusters in strata, according to mean household income) is described in detail, in addition to measurement methods, and training of observers. Indicators of performance in field work and quality control are also presented as results of the application of the metodology of study.

16.
Brain Dev ; 17(2): 114-6, 1995.
Article in English | MEDLINE | ID: mdl-7625544

ABSTRACT

We report a case of non-familial hyperekplexia which characteristically developed apnea and feeding difficulties in the neonatal period. The abnormal startle response was evident from the second week of life onwards. The infant showed a marked improvement of the startle response and muscle hypertonia with clonazepam. Clobazam was also tried with no apparent response. A prominent long latency C response was observed on EMG examination, suggesting a possible cortical neuronal hyperexcitability origin for the abnormal startle response observed in hyperekplexia.


Subject(s)
Anti-Anxiety Agents , Apnea/etiology , Benzodiazepines , Movement Disorders/physiopathology , Reflex, Startle , Benzodiazepinones/therapeutic use , Clobazam , Clonazepam/therapeutic use , Electromyography , Female , Humans , Infant, Newborn , Movement Disorders/diagnosis , Reflex
17.
J Pediatr (Rio J) ; 71(1): 41-4, 1995.
Article in Portuguese | MEDLINE | ID: mdl-14689035

ABSTRACT

Epignathus is a congenital teratoide tumor in the oral cavity. It is extremely rare and usually lethal. The authors present a case treated successfully. Important aspects of the diagnosis, clinical management and surgical procedures are discussed. Extensive review of the literature is presented.

18.
J. bras. urol ; 9(2): 63-5, 1983.
Article in Portuguese | LILACS | ID: lil-16307

ABSTRACT

A pielonefrite enfisematosa e uma patologia rara, com acentuado indice de morbidade e mortalidade. Os autores relatam o 45o. caso encontrado na literatura mundial com orientacao para seu diagnostico e tratamento eficaz


Subject(s)
Adult , Humans , Male , Emphysema , Pyelonephritis , Pre-Eclampsia
19.
An Acad Bras Cienc ; 53(4): 683-91, 1981 Dec.
Article in English | MEDLINE | ID: mdl-7345962

ABSTRACT

Two types of portable instruments were developed by the former Health and Safety Laboratory of the U.S. Atomic Energy Commission to characterize external gamma radiation fields and to estimate individual exposure dose rates from major natural or fission radionuclides distributed in the soil: a pressurized ionization chamber and a NaI(T1) gamma-ray spectrometer. The two instruments were used to measure environmental radiation exposure rates at three distinct geological areas of Brazil: - in the towns of Guarapari and Meaípe located on the monazite sand belt, ES. - on the vicinities of the uranium mine of Poços de Caldas, MG. - around the site of the Brazilian first nuclear power plant, in Angra dos Reis, RJ. The radiometric survey demonstrated once more the usefulness and versatility of the two instruments used. The measurements around the nuclear installations of Poços de Caldas and Angra dos Reis, allowed a rapid assessment of the local radiation background and its variability, as well as the selection of stations for the routine monitoring program. Radioactive anomalies were detected and characterized previously to the start of plant operations. The survey in Guarapari and Meaípe confirmed the results obtained by Roser and Cullen in 1958 and 1962, except on sites where considerable changes took place since then. The spectrometric measurements gave estimations of the relative proportion of 40K, 238U and 232Th series in the ground and also indications on the homogeneity of their distribution in the soil.


Subject(s)
Potassium Radioisotopes , Radioactivity , Soil Pollutants, Radioactive/analysis , Soil Pollutants/analysis , Thorium , Uranium , Brazil , Geography , Spectrometry, Gamma
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