Evaluation of the QuEChERS method and gas chromatography-mass spectrometry for the analysis pesticide residues in water and sediment.

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.

Evaluation of the mineral profile of textile materials using inductively coupled plasma optical emission spectrometry and chemometrics.

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.

The association of ACE gene D/I polymorphism with cardiovascular risk factors in a population from Rio de Janeiro.

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.

The association of ACE gene D/I polymorphism with cardiovascular risk factors in a population from Rio de Janeiro

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.

Effect of pre-treatment and supporting media on Ni(II), Cu(II), Al(III) and Fe(III) sorption by plant root material.

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.

An attempt to correlate fat and protein content of biological samples with residual carbon after microwave-assisted digestion.

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.

Determination of dysprosium and europium in sheep faeces by graphite furnace and tungsten coil electrothermal atomic absorption spectrometry.

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.

Single vessel procedure for acid-vapour partial digestion in a focused microwave: Fe and Co determination in biological samples by ETAAS.

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.

Vanillin-condensed tannin study using flow injection spectrophotometry.

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.

Potentiometric determination of urea by sequential injection using Jack bean meal crude extract as a source of urease.

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.

Determination of ytterbium in animal faeces by tungsten coil electrothermal atomic absorption spectrometry.

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.

Sistema polivalente de análises químicas por injeção em fluxo: determinação espectrofotométrica de cálcio, magnésio e fósforo em plantas

A polyvalent flow injection system was proposed for spectrophotometric determination of calcium, magnesium and phosphorus in acid plant digests. O-cresolphtalein complexone (CPC) was the chromogenic reagent for calcium and magnesium determination, and ammonium molybdate/vanadate for phosphorus determination. Ammonium-ammonia was elected as buffer system, and EGTA or 8-hydroxyquinoline as the masking agents for calcium or magnesium. Linearity of the calibration equations was observed up to 40.0 mg Ca L-1, 10.0 mg Mg L-1 and 16.0 mg P L-1. Slight variations in the coefficients of the calibration equations (usually 3 %) were found after 4-h working periods. Precise results (r.s.d. 0.02), in agreement with alternative method (flame atomic absorption spectrometry) were obtained. When the system was applied to large scale analysis, good repeatability was observed, and a sample throughput, of about 107 h-1 for magnesium and 75 h-1 for calcium and phosphorus was achieved, emphasizing the simplicity, robustness and versatility inherent to flow analysis.

Um sistema polivalente de análises químicas por injeção em fluxo foi proposto para a determinação de cálcio, magnésio e fósforo em digeridos ácidos de plantas. O-cresolphtaleina complexona (CPC) foi selecionado como reagente colorimétrico para a determinação de cálcio e magnésio e molibdato de amônio/vanadato de amônio para a determinação de fósforo. O sistema empregou tampão amônio-amônia (pH 10,5) e EGTA ou 8-hidroxiquinolina como agentes mascarantes para cálcio ou magnésio, respectivamente. Equações de calibração lineares foram obtidas, sendo que para facilitar a utilização do sistema proposto, foi utilizada curva analítica mista (até 40,0 mg Ca L-1, 10,0 mg Mg L-1 e 16,0 mg P L-1), não sendo observadas interferências entre os elementos. Os limites de detecção foram: 0,10; 0,05 e 0,004 FONT FACE="Symbol">m /font>g L-1 respectivamente para Ca, Mg e P. Pequenas modificações no coeficiente das equações de calibração (normalmente 3%) foram observadas após períodos de 4 h de trabalho. Os resultados apresentaram-se precisos (d.p.r. 0,02), e em concordância com método alternativo (espectrometria de absorção atômica). Quando o sistema foi aplicado a análises em rotina, boa repetibilidade foi observada, sendo obtidas velocidade de amostragem de 107 amostras h-1 para magnésio e 75 amostras h-1 para cálcio e fósforo, enfatizando a simplicidade, robustez e versatilidade, inerentes aos sistemas de análises por injeção em fluxo.

SISTEMA POLIVALENTE DE ANÁLISES QUÍMICAS POR INJEÇÃO EM FLUXO: DETERMINAÇÃO ESPECTROFOTOMÉTRICA DE CÁLCIO, MAGNÉSIO E FÓSFORO EM PLANTAS

A polyvalent flow injection system was proposed for spectrophotometric determination of calcium, magnesium and phosphorus in acid plant digests. O-cresolphtalein complexone (CPC) was the chromogenic reagent for calcium and magnesium determination, and ammonium molybdate/vanadate for phosphorus determination. Ammonium-ammonia was elected as buffer system, and EGTA or 8-hydroxyquinoline as the masking agents for calcium or magnesium. Linearity of the calibration equations was observed up to 40.0 mg Ca L-1, 10.0 mg Mg L-1 and 16.0 mg P L-1. Slight variations in the coefficients of the calibration equations (usually 3 %) were found after 4-h working periods. Precise results (r.s.d. 0.02), in agreement with alternative method (flame atomic absorption spectrometry) were obtained. When the system was applied to large scale analysis, good repeatability was observed, and a sample throughput, of about 107 h-1 for magnesium and 75 h-1 for calcium and phosphorus was achieved, emphasizing the simplicity, robustness and versatility inherent to flow analysis.

Um sistema polivalente de análises químicas por injeção em fluxo foi proposto para a determinação de cálcio, magnésio e fósforo em digeridos ácidos de plantas. O-cresolphtaleina complexona (CPC) foi selecionado como reagente colorimétrico para a determinação de cálcio e magnésio e molibdato de amônio/vanadato de amônio para a determinação de fósforo. O sistema empregou tampão amônio-amônia (pH 10,5) e EGTA ou 8-hidroxiquinolina como agentes mascarantes para cálcio ou magnésio, respectivamente. Equações de calibração lineares foram obtidas, sendo que para facilitar a utilização do sistema proposto, foi utilizada curva analítica mista (até 40,0 mg Ca L-1, 10,0 mg Mg L-1 e 16,0 mg P L-1), não sendo observadas interferências entre os elementos. Os limites de detecção foram: 0,10; 0,05 e 0,004 FONT FACE="Symbol">m /font>g L-1 respectivamente para Ca, Mg e P. Pequenas modificações no coeficiente das equações de calibração (normalmente 3%) foram observadas após períodos de 4 h de trabalho. Os resultados apresentaram-se precisos (d.p.r. 0,02), e em concordância com método alternativo (espectrometria de absorção atômica). Quando o sistema foi aplicado a análises em rotina, boa repetibilidade foi observada, sendo obtidas velocidade de amostragem de 107 amostras h-1 para magnésio e 75 amostras h-1 para cálcio e fósforo, enfatizando a simplicidade, robustez e versatilidade, inerentes aos sistemas de análises por injeção em fluxo.

[Abdominal cystic lymphangioma in childhood: report of eight cases]. / Linfangioma abdominal na criança: apresentação de oito casos.

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.

[Arterial hypertension in Ilha do Governador, Rio de Janeiro, Brazil: II. Prevalence]. / Hipertensão arterial na Ilha do Governador, Brasil: II. Prevalência.

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.

[Arterial hypertension in Ilha do Governador, Rio de Janeiro, Brazil: I. Methodology]. / Hipertensão arterial na Ilha do Governador, Rio de Janeiro, Brasil: I. Metodologia.

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.

Hyperekplexia, a cause of neonatal apnea: a case report.

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.

[Giant epignathus in the newborn: report of a case and review of the literature]. / Epignathus gigante no recém nascido: relato de um caso e revisão da literatura.

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.

Avaliação de genótipos de Leucaena spp. nas condições edafoclimáticas de São Carlos, SP: I. caracterização fenotípica e avaliação agronômica

To test promising genotypes of Leucaena spp., selected in a breeding program, an experiment was conducted in a distrofic Red-Yellow Latossol, at the experimental station of EMBRAPA/CPPSE, São Carlos,SP, located at 22°01' and 47°53'W, altitude of 856 m and with a mean annual precipitation of 1502 mm. The following genotypes were tested: L.leucocephala cv. Texas 1074 (T1), L.leucocephala 29 A9 (T2), L.leucocephala 11 x L.diversifolia 25 (T3), L.leucocephala 11 x L.diversifolia 26 (T4), L.leucocephala 24-19/2-39 x L.diversifolia 26 (T5) and L.leucocephala cv. Cunningham (control). Evaluations were performed during the establishment period (fifteen months) and it was concluded that: a) the plants of L.leucocephala 24-19/2-39 x L.diversifolia 26, with early flowering, were the most branched and presented the greatest seed yield; b) the plants of L.leucocephala 11 x L.diversifolia 26, showed the greatest edible dry matter yield; c) the genotypes presented similar or worse growth, than the control, after each harvest.

Para avaliar genótipos promissores de Leucaena spp., foi instalado experimento em Latossolo Vermelho-Amarelo distrófico, na área da EMBRAPA-CPPSE em São Carlos, situada a 22°01'S e 47°53'W, com altitude de 856 m e média de precipitação anual de 1502 mm. Foram testados os seguintes genótipos: Leucaena leucocephala cv. Texas 1074 (T1), L.leucocephala 29 A9 (T2), L.leucocephala 11 x L.diversifolia 25 (T3), L.leucocephala 11 x L.leucocephala 26 (T4), L.leucocephala 24-19/2-39 X L.diversifolia 26 (T5) e L.leucocephala cv. Cunningham (testemunha). Através das avaliações efetuadas durante o período de estabelecimento (15 meses), verificou-se que: a) as plantas de L.leucocephala 24-19/2-39 x L.diversifolia 26 se mostraram mais ramificadas e com maior produção de sementes; b) as plantas de L.leucocephala 11 x L.diversifolia 26 apresentaram a maior produção de matéria seca consumível; c) os materiais apresentaram brotação após o corte, semelhante ou inferior à testemunha.