993 resultados para ESTRONE SULFATE
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OBJECTIVE: To analyze the amount of glycosaminoglycans in the uterine cervix during each phase of the rat estrous cycle. DESIGN: Based on vaginal smears, forty female, regularly cycling rats were divided into four groups (n = 10 for each group): GI - proestrous, GII - estrous, GIII - metaestrous and GIV - diestrous. Animals were sacrificed at each phase of the cycle, and the cervix was immediately removed and submitted to biochemical extraction and determination of sulfated glycosaminoglycans and hyaluronic acid. The results were analyzed by ANOVA followed by the Bonferroni post-hoc test. RESULTS: The uterine cervix had the highest amount of total sulfated glycosaminoglycans and dermatan sulfate during the estrous phase (8.90 ± 0.55 mg/g of cetonic extract, p<0.001; and 8.86 ± 0.57 mg/g of cetonic extract, p<0.001). In addition, there was more heparan sulfate at the cervix during the proestrous phase (0.185 ± 0.03 mg/g of cetonic extract) than during any other phase (p<0.001). There were no significant changes in the concentration of hyaluronic acid in the uterine cervix during the estrous cycle. CONCLUSION: Our data suggest that the amount of total sulfated glycosaminoglycans may be influenced by hormonal fluctuations related to the estrous cycle, with dermatan sulfate and heparan sulfate being the glycosaminoglycans most sensitive to hormonal change.
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An analytical procedure for determination of estriol, 17β-estradiol, estrone and 17α-ethinylestradiol in drinking water is presented. The method employs solid phase extraction (SPE) and sample dechlorination as cleanup procedures, followed by HPLC-DAD analysis. Validation was carried out using RE No. 899/2003 guidelines established by the Agência Nacional de Vigilância Sanitária (National Agency of Sanitary Surveillance, Brazil), with some adaptations. The statistically evaluated results have shown that the method is selective, precise (0,06% to 19,40% CV) and accurate (91,52% to 109,41% average recoveries). The developed method was applied to the analysis of these contaminants in drinking water from São Luís, MA.
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Um método espectrofotométrico simples foi desenvolvido para a determinação do bromidrato de fenoterol (BF) em comprimidos, gotas e xarope, como princípio ativo único e associado ao ibuprofeno. O método se baseia na reação de acoplamento oxidativo do BF com o 3-metil-2-benzotiazolinona hidrazona (MBTH), na presença de sulfato cérico, como agente oxidante. A mistura de BF, MBTH e sulfato cérico, em meio ácido, produz um composto colorido (vermelho castanho) com máximo de absorção a 475 nm. A curva de calibração foi linear num intervalo de concentração de 3,0 a 12,0 µg/mL, com coeficiente de correlação linear de 0,9998. Os parâmetros experimentais que afetam o desenvolvimento e a estabilidade do produto colorido foram cuidadosamente estudados e otimizados. O método foi aplicado em amostras comerciais e simuladas, obtendo-se coeficientes de variação entre 0,25 % a 0,82 % e médias de recuperação do padrão que variaram de 98 % a 102 %. O método proposto mostrou-se exato, preciso, linear e não é passível de interferência de excipientes, para as formas farmacêuticas comprimidos e gotas. Não houve interferência do ibuprofeno que consta de uma das formulações analisadas, associado ao BF. Quanto ao xarope, houve interferência do veículo sugerindo reações de seus componentes com o MBTH.
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Foram conduzidos dois experimentos para avaliar fontes orgânicas e inorgânicas de zinco e cobre nas dietas e seus efeitos no desempenho de leitões desmamados aos 21 dias de idade. Em cada experimento, foram utilizados 90 leitões em delineamento experimental de blocos ao acaso, com cinco dietas, seis repetições e três animais por parcela. As dietas utilizadas nos experimentos 1 e 2 continham 120 ppm de zinco e 10 ppm de cobre na forma de sulfato. No experimento 1, foram suplementadas com 0, 300, 600 e 900 ppm de zinco na forma orgânica ou 2.400 ppm na forma de óxido (ZnO) e, no experimento 2, com 0, 50, 100 e 150 ppm de cobre na forma orgânica ou 240 ppm de cobre na forma de sulfato (CuSO4 H2O). No experimento 1, os níveis de zinco de fonte orgânica tiveram efeito linear no consumo de ração e no ganho de peso nos períodos de 0 a 15 dias e de 0 a 21 dias pós-desmame. O ganho de peso nas fases de 0 a 35 dias e de 0 a 42 dias pós-desmame e o consumo de ração dos leitões que receberam a dieta com 900 ppm de zinco de fonte orgânica não diferiram dos valores observados naqueles que receberam a dieta com 2.400 ppm de zinco na forma inorgânica. A suplementação da dieta com zinco na forma orgânica (900 ppm) ou inorgânica (2.400 ppm) aumentou o consumo de ração e o ganho de peso de leitões nas primeiras três semanas após o desmame. A suplementação da dieta com 2.400 ppm de zinco na forma inorgânica reduziu a incidência de diarreia nas primeiras três semanas pós-desmame. No experimento 2, os níveis de cobre de fonte orgânica tiveram efeito quadrático no consumo de ração dos leitões nos períodos de 0 a 31 e de 0 a 40 dias pós-desmame. A suplementação da dieta com cobre, tanto de fonte orgânica (90 ppm) como inorgânica (240 ppm), aumenta o consumo de ração e o ganho de peso de leitões nos primeiros 40 dias pós-desmame.
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Avaliou-se a biodisponibilidade de ferro de diferentes compostos visando sua utilização em dietas para leitões desmamados. Utilizaram-se 44 leitões (7 não-anêmicos e 37 anêmicos) desmamados aos 21 dias de idade (7,3 ± 1,8 kg) e distribuídos em dois grupos: grupo não-anêmico e grupo anêmico. Durante sete dias, os animais do grupo não-anêmico receberam dieta com FeSO4.7H2O (sulfato ferroso hepta-hidratado) na dose de 100 mg/kg e os do grupo anêmico, dieta sem ferro (<15 mg/kg ração). No sétimo dia, depois de determinada a concentração de hemoglobina sanguínea e diagnosticada a anemia, os leitões foram agrupados segundo o produto do peso (kg) × hemoglobina (g/dL) e alojados individualmente, durante 13 dias, em gaiolas para estudos de digestibilidade, onde foram alimentados com seis rações à base de milho e leite em pó: três rações-padrão com FeSO4.7H2O em quantidade equivalente a 80, 150 e 200 mg Fe/kg de ração; duas rações experimentais com ferro (150 mg/kg) na forma de FeSO4 microencapsulado com carboximetilcelulose ou de ferro quelado com metionina; e uma controle com ferro (100 mg/kg). O consumo de ração foi medido diariamente. Nos dias 0, 3, 6, 9 e 13 do período de repleção, os animais foram pesados para avaliação do desempenho e o sangue foi coletado para determinação da concentração de hemoglobina. Ao final do ensaio, os animais foram sacrificados e o fígado foi coletado para determinação das concentrações de ferro total, ferro heme e ferro não-heme. As concentrações hepáticas de ferro heme, ferro não-heme e ferro total não diferiram entre os animais, entretanto, os do grupo controle apresentaram excesso de ferro total no fígado, relacionado à dose de ferro injetada nos leitões após o desmame. Em comparação ao FeSO4.7H2O não encapsulado, os compostos de ferro microencapsulado com carboximetilcelulose e de ferro quelado com metionina promovem melhor conversão alimentar em leitões desmamados.
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OBJETIVO: Avaliar a efetividade da suplementação universal profilática com sulfato ferroso, em administração diária ou semanal, na prevenção da anemia em lactentes. MÉTODOS: Ensaio de campo randomizado com crianças de seis a 12 meses de idade, atendidas em unidades básicas de saúde do município do Rio de Janeiro, em 2004-2005. Foram formadas três coortes concorrentes com suplementação universal com sulfato ferroso com grupos: diário (n=150; 12,5mgFe/dia), semanal (n=147; 25mgFe/semana) e controle (n=94). A intervenção durou 24 semanas e foi acompanhada por ações educativas promotoras de adesão. A concentração de hemoglobina sérica foi analisada segundo sua distribuição, média e prevalência de anemia (Hb<110,0g/L) aos 12 meses de idade. A avaliação da efetividade foi realizada segundo intenção de tratar e adesão ao protocolo, utilizando-se análises de regressão múltipla (linear e de Poisson). RESULTADOS: Os grupos mostraram-se homogêneos quanto às variáveis de caracterização. A intervenção foi operacionalizada com sucesso, com elevada adesão ao protocolo em ambos os grupos expostos a ela, sem diferença estatística entre eles. Após ajuste, somente o esquema diário apresentou efeito protetor. Na análise por adesão, o esquema diário apresentou evidente efeito dose-resposta para média de hemoglobina sérica e prevalência de anemia, não sendo observado nenhum efeito protetor do esquema semanal. CONCLUSÕES: Apenas o esquema diário de suplementação universal com sulfato ferroso dos seis aos 12 meses de idade foi efetivo em aumentar a concentração de hemoglobina sérica e em reduzir o risco de anemia
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Heparin has been shown to regulate human neutrophil elastase (HNE) activity. We have assessed the regulatory effect of heparin on Tissue Inhibitor of Metalloproteases-1 [TIMP-1] hydrolysis by HNE employing the recombinant form of TIMP-1 and correlated FRET-peptides comprising the TIMP-1 cleavage site. Heparin accelerates 2.5-fold TIMP-1 hydrolysis by HNE. The kinetic parameters of this reaction were monitored with the aid of a FRET-peptide substrate that mimics the TIMP-1 cleavage site in pre-steady-state conditionsby using a stopped-flow fluorescence system. The hydrolysis of the FRET-peptide substrate by HNE exhibits a pre-steady-state burst phase followed by a linear, steady-state pseudo-first-order reaction. The HNE acylation step (k(2)=21 +/- 1 s(-1)) was much higher than the HNE deacylation step (k(3)=0.57 +/- 0.05 s(-1)). The presence of heparin induces a dramatic effect in the pre-steady-state behavior of HNE. Heparin induces transient lag phase kinetics in HNE cleavage of the FRET-peptide substrate. The pre-steady-state analysis revealed that heparin affects all steps of the reaction through enhancing the ES complex concentration, increasing k(1) 2.4-fold and reducing k(-1) 3.1-fold. Heparin also promotes a 7.8-fold decrease in the k(2) value, whereas the k(3) value in the presence of heparin was increased 58-fold. These results clearly show that heparin binding accelerates deacylation and slows down acylation. Heparin shifts the HNE pH activity profile to the right, allowing HNE to be active at alkaline pH. Molecular docking and kinetic analysis suggest that heparin induces conformational changes in HNE structure. Here, we are showing for the first time that heparin is able to accelerate the hydrolysis of TIMP-1 by HNE. The degradation of TIMP-1is associated to important physiopathological states involving excessive activation of MMPs.
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Background: Cytoadherence of Plasmodium falciparum-infected red blood cells is mediated by var gene-encoded P. falciparum erythrocyte membrane protein-1 and host receptor preference depends in most cases on which of the 50-60 var genes per genome is expressed. Enrichment of phenotypically homogenous parasites by panning on receptor expressing cells is fundamental for the identification of the corresponding var transcript. Methods: P. falciparum 3D7 parasites were panned on several transfected CHO-cell lines and their var transcripts analysed by i) reverse transcription/PCR/cloning/sequencing using a universal DBL alpha specific oligonucleotide pair and ii) by reverse transcription followed by quantitative PCR using 57 different oligonucleotide pairs. Results: Each cytoadherence selected parasite line also adhered to untransfected CHO-745 cells and upregulation of the var gene PFD995/PFD1000c was consistently associated with cytoadherence to all but one CHO cell line. In addition, parasites panned on different CHO cell lines revealed candidate var genes which reproducibly associated to the respective cytoadherent phenotype. The transcription profile obtained by RT-PCR/cloning/sequencing differed significantly from that of RT-quantitative PCR. Conclusion: Transfected CHO cell lines are of limited use for the creation of monophenotypic cytoadherent parasite lines. Nevertheless, 3D7 parasites can be reproducibly selected for the transcription of different determined var genes without genetic manipulation. Most importantly, var transcription analysis by RT-PCR/cloning/sequencing may lead to erroneous interpretation of var transcription profiles.
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Atmospheric aerosol particles serving as cloud condensation nuclei (CCN) are key elements of the hydrological cycle and climate. We have measured and characterized CCN at water vapor supersaturations in the range of S=0.10-0.82% in pristine tropical rainforest air during the AMAZE-08 campaign in central Amazonia. The effective hygroscopicity parameters describing the influence of chemical composition on the CCN activity of aerosol particles varied in the range of kappa approximate to 0.1-0.4 (0.16+/-0.06 arithmetic mean and standard deviation). The overall median value of kappa approximate to 0.15 was by a factor of two lower than the values typically observed for continental aerosols in other regions of the world. Aitken mode particles were less hygroscopic than accumulation mode particles (kappa approximate to 0.1 at D approximate to 50 nm; kappa approximate to 0.2 at D approximate to 200 nm), which is in agreement with earlier hygroscopicity tandem differential mobility analyzer (H-TDMA) studies. The CCN measurement results are consistent with aerosol mass spectrometry (AMS) data, showing that the organic mass fraction (f(org)) was on average as high as similar to 90% in the Aitken mode (D <= 100 nm) and decreased with increasing particle diameter in the accumulation mode (similar to 80% at D approximate to 200 nm). The kappa values exhibited a negative linear correlation with f(org) (R(2)=0.81), and extrapolation yielded the following effective hygroscopicity parameters for organic and inorganic particle components: kappa(org)approximate to 0.1 which can be regarded as the effective hygroscopicity of biogenic secondary organic aerosol (SOA) and kappa(inorg)approximate to 0.6 which is characteristic for ammonium sulfate and related salts. Both the size dependence and the temporal variability of effective particle hygroscopicity could be parameterized as a function of AMS-based organic and inorganic mass fractions (kappa(p)=kappa(org) x f(org)+kappa(inorg) x f(inorg)). The CCN number concentrations predicted with kappa(p) were in fair agreement with the measurement results (similar to 20% average deviation). The median CCN number concentrations at S=0.1-0.82% ranged from N(CCN,0.10)approximate to 35 cm(-3) to N(CCN,0.82)approximate to 160 cm(-3), the median concentration of aerosol particles larger than 30 nm was N(CN,30)approximate to 200 cm(-3), and the corresponding integral CCN efficiencies were in the range of N(CCN,0.10/NCN,30)approximate to 0.1 to N(CCN,0.82/NCN,30)approximate to 0.8. Although the number concentrations and hygroscopicity parameters were much lower in pristine rainforest air, the integral CCN efficiencies observed were similar to those in highly polluted megacity air. Moreover, model calculations of N(CCN,S) assuming an approximate global average value of kappa approximate to 0.3 for continental aerosols led to systematic overpredictions, but the average deviations exceeded similar to 50% only at low water vapor supersaturation (0.1%) and low particle number concentrations (<= 100 cm(-3)). Model calculations assuming aconstant aerosol size distribution led to higher average deviations at all investigated levels of supersaturation: similar to 60% for the campaign average distribution and similar to 1600% for a generic remote continental size distribution. These findings confirm earlier studies suggesting that aerosol particle number and size are the major predictors for the variability of the CCN concentration in continental boundary layer air, followed by particle composition and hygroscopicity as relatively minor modulators. Depending on the required and applicable level of detail, the information and parameterizations presented in this paper should enable efficient description of the CCN properties of pristine tropical rainforest aerosols of Amazonia in detailed process models as well as in large-scale atmospheric and climate models.
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The alternative low-spin states of Fe3+ and Fe2+ cytochrome c induced by SDS or AOT/hexane reverse micelles exhibited the heme group in a less rhombic symmetry and were characterized by electron paramagnetic resonance, UV-visible, CD, magnetic CD, fluorescence, and Raman resonance. Consistent with the replacement of Met 80 by another strong field ligand at the sixth heme iron coordination position, Fe3+ ALSScytc exhibited 1-nm Soret band blue shift and e enhancement accompanied by disappearance of the 695-nm charge transfer band. The Raman resonance, CD, and magnetic CD spectra of Fe3+ and Fe2+ ALSScytc exhibited significant changes suggestive of alterations in the heme iron microenvironment and conformation and should not be assigned to unfold because the Trp(59) fluorescence remained quenched by the neighboring heme group. ALSScytc was obtained with His(33) and His(26) carboxyethoxylated horse cytochrome c and with tuna cytochrome c (His(33) replaced by Asn) pointing out Lys(79) as the probable heme iron ligand. Fe3+ ALSScytc retained the capacity to cleave tert-butylhydroperoxide and to be reduced by dithiothreitol and diphenylacetaldehyde but not by ascorbate. Compatible with a more open heme crevice, ALSScytc exhibited a redox potential similar to 200 mV lower than the wild-type protein (1220 mV) and was more susceptible to the attack of free radicals.
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Ethanol oxidation has been studied on Pt(111), Pt(100) and Pt(110) electrodes in order to investigate the effect of the surface structure and adsorbing anions using electrochemical and FTIR techniques. The results indicate that the surface structure and anion adsorption affect significantly the reactivity of the electrode. Thus, the main product of the oxidation of ethanol on the Pt(111) electrode is acetic acid, and acetaldehyde is formed as secondary product. Moreover, the amount of CO formed is very small, and probably associated with the defects present on the electrode surface. For that reason, the amount of CO(2) is also small. This electrode has the highest catalytic activity for the formation of acetic acid in perchloric acid. However, the formation of acetic acid is inhibited by the presence of specifically adsorbed anions, such as (bi) sulfate or acetate, which is the result of the formation of acetic acid. On the other hand, CO is readily formed at low potentials on the Pt(100) electrode, blocking completely the surface. Between 0.65 and 0.80 V, the CO layer is oxidized and the production of acetaldehyde and acetic acid is detected. The Pt(110) electrode displays the highest catalytic activity for the splitting of the C-C bond. Reactions giving rise to CO formation, from either ethanol or acetaldehyde, occur at high rate at any potential. On the other hand, the oxidation of acetaldehyde to acetic acid has probably the lower reaction rate of the three basal planes.
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Concentrations of cations (Na(+), Ca(2+), Mg(2+), K(+), NH(4) (+)), anions (HCO(3) (-), Cl(-), NO(3) (-), SO(4) (2-), PO(4) (3-)) and suspended sediments in the Madeira River water were determined near the city of Porto Velho (RO), in order to assess variation in water chemistry from 2004 to 2007. Calcium and bicarbonate were the dominant cation and anion, respectively. Significant seasonal differences were found, with highest concentrations occurring during the dry season, as expected from the drainage of Andean carbonate-rich substratum. Interannual variations were also observed, but became significant only when annual average discharge was 25% less than normal. Under this atypical discharge condition, bicarbonate was replaced by sulfate, and higher suspended sediment concentrations and loads were also observed. Compared to previously published studies, it appears that no significant changes in water chemistry have occurred during the last 20-30 years, although differences in approaches and sampling designs among this and previous studies may not allow detection of modest changes. The calculated suspended sediment load reported here is close to the values presented elsewhere, reinforcing the relative importance of this river as a sediment supplier for the Amazon Basin. Seasonality has a significant control on the chemistry of Madeira River waters, and severe decrease in discharge due to anthropogenic changes, such as construction of reservoirs or the occurrence of drier years-a plausible consequence of global climate change-may lead to modification in the chemical composition as well in the sediment deliver to the Amazon River.
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An antimicrobial peptide produced by a bacterium isolated from the effluent pond of a bovine abattoir was purified and characterized. The strain was characterized by biochemical profiling and 16S rDNA sequencing as Pseudomonas sp. The antimicrobial peptide was purified by ammonium sulfate precipitation, gel filtration, and ion exchange chromatography. Direct activity on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was observed. A major band on SDS-PAGE suggested that the antimicrobial peptide has a molecular mass of about 30 kDa. The substance was inhibitory to a broad range of indicator strains, including pathogenic and food spoilage bacteria such as Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, among other. The partially purified antimicrobial substance remained active over a wide temperature range and was resistant to all proteases tested. This substance showed different properties than other antimicrobials from Pseudomonas species, suggesting a novel antimicrobial peptide was characterized.
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In the current work a Green Analytical Chemistry (GAC) procedure for photometric determination of orthophosphate in river water at mu g L-1 concentration level is described. The flow system module and the LED-based photometer were assembled together to constitute a compact unit in order to allow that a flow cell with optical path-length of 100mm was coupled to them. The photometric procedure based on the molybdenum blue method was implemented employing the multicommuted flow injection analysis approach, which provided facilities to allow reduction of reagent consumption and as well as waste generation. Aiming to prove the usefulness of the system, orthophosphate in river and tap waters was determined. Accuracy was ascertained by spiking samples with orthophosphate solution yielding recoveries ranging from 96% up to 107%. Other profitable features such as a wide linear response range between 10 to 800 mu g L-1 [image omitted]; a detection limit (3 sigma criterion) of 2.4 mu g L-1 [image omitted]; a relative standard deviation (n=7) of 2% using a typical water sample with concentration of 120 mu g L-1 [image omitted]; reagent consumption of 3.0mg ammonium molybdate, 0.3mg hydrazine sulfate, and 0.03mg stannous chloride per determination; a waste generation of 2.4mL per determination; and a sampling throughput of 20 determination per hours were also achieved.
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The presence of sexual hormones (female estrogens) was assessed in sediments of a mangrove located in the urban region of southern Brazil. The estrogens are involved in human sexual reproduction. They act as the chemical messengers, and they are classified as natural and synthetic. The estrogens inputs in the environment are from treated and untreated sewage. The presence of estrogens in sewage is excretion from the female due to natural production and use of contraceptives (synthetic estrogens). With the indiscriminate release of sewage into the environment, estrogens can be found in rivers, lakes, and even in oceans. In this work, the presence of estrone (E1), 17-beta-estradiol (E2), and 17-alpha-ethynilestradiol (EE2) in eight sedimentary stations in Itacorubi mangrove located on Santa Catarina Island, south Brazil, was investigated. Historically, the Itacorubi mangrove has been impacted by anthropogenic activities because the mangrove is inserted in the urban area of the Florianopolis. The estrogen EE2, used as contraceptive, had the highest concentration in mangrove sediment, 129.75 +/- 3.89 ng/g. E2 was also found, with its concentration ranging from 0.90 +/- 0.03 to 39.77 +/- 1.19 ng/g. Following the mechanism, under aerobic or anaerobic conditions, E2 will first be oxidized to E1, which is further oxidized to unknown metabolites and finally to CO(2) and water (mineralized). EE2 is oxidized to unknown metabolites and also finally mineralized. Theoretically, under anaerobic conditions, EE2 can be reduced to E1 even in environments such as mangrove which is essentially anaerobic.