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1.
J Dairy Sci ; 103(8): 7068-7080, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32505403

RESUMEN

Undesirable interactions between trace mineral elements and ruminal contents may occur during digestion when mineral salts are supplemented. Antimicrobial effects of copper sulfate (CuSO4) may affect ruminal digestibility of nutrients when fed as a source of copper (Cu), while sodium selenite (Na2SeO3) may be reduced in the rumen to less available forms of selenium (Se). Our objective was to evaluate if protection of CuSO4 and Na2SeO3 by lipid-microencapsulation would induce changes on ruminal microbial fermentation. We used 8 fermentors in a dual-flow continuous-culture system in a 4 × 4 duplicated Latin square with a 2 × 2 factorial arrangement of treatments. Factors were CuSO4 protection (unprotected and protected by lipid-microencapsulation) and Na2SeO3 protection (unprotected and protected by lipid-microencapsulation). Treatments consisted of supplementation with 15 mg/kg of Cu and 0.3 mg/kg of Se from either unprotected or protected (lipid-microencapsulated) sources, as follows: (1) Control (unprotected CuSO4 + unprotected Na2SeO3); (2) Cu-P (protected CuSO4 + unprotected Na2SeO3); (3) Se-P (unprotected CuSO4 + protected Na2SeO3); (4) (Cu+Se)-P (protected CuSO4 + protected Na2SeO3). All diets had the same nutrient composition and fermentors were fed 106 g of dry matter/d. Each experimental period was 10 d (7 d of adaptation and 3 d for sample collections). Daily pooled samples of effluents were analyzed for pH, NH3-N, nutrient digestibility, and flows (g/d) of total N, NH3-N, nonammonia N (NAN), bacterial N, dietary N, and bacterial efficiency. Kinetics of volatile fatty acids was analyzed in samples collected daily at 0, 1, 2, 4, 6, and 8 h after feeding. Main effects of Cu protection, Se protection, and their interaction were tested for all response variables. Kinetics data were analyzed as repeated measures. Protection of Cu decreased acetate molar proportion, increased butyrate proportion, and tended to decrease acetate:propionate ratio in samples of kinetics, but did not modify nutrient digestibility. Protection of Se tended to decrease NH3-N concentration, NH3-N flow, and CP digestibility; and to increase flows of nonammonia N and dietary N. Our results indicate that protection of CuSO4 may increase butyrate concentration at expenses of acetate, while protection of Na2SeO3 tended to reduce ruminal degradation of N. Further research is needed to determine the effects of lipid-microencapsulation on intestinal absorption, tissue distribution of Cu and Se, and animal performance.


Asunto(s)
Bacterias/efectos de los fármacos , Bovinos/fisiología , Sulfato de Cobre/administración & dosificación , Suplementos Dietéticos/análisis , Ácidos Grasos Volátiles/metabolismo , Selenito de Sodio/administración & dosificación , Alimentación Animal/análisis , Animales , Bacterias/metabolismo , Reactores Biológicos/veterinaria , Bovinos/microbiología , Técnicas de Cultivo/veterinaria , Dieta/veterinaria , Digestión , Composición de Medicamentos/veterinaria , Femenino , Fermentación/efectos de los fármacos , Lípidos/química , Nutrientes/metabolismo , Rumen/metabolismo , Rumen/microbiología , Oligoelementos/metabolismo
2.
J Appl Microbiol ; 125(4): 1208-1215, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29920871

RESUMEN

AIMS: To improve RT-qPCR with an internal control and a synthetic standard curve to detect HEV in HIV co-infected patients. METHODS AND RESULTS: A single-stranded RNA (ssRNA) and a double-stranded DNA (dsDNA) synthetic curve were designed, compared to the international reference panel for HEV genotypes, and tested to quantify and detect a reference panel for HEV genotypes. The detection limit of the RNA synthetic curve (50 copies per ml) was better than the DNA synthetic curve (100 copies per ml) and the WHO standard curve (250 copies per ml). Then, 280 serum samples from HIV-positive patients were tested for HEV RNA, which was detected in 3·6% of serum samples. The viral load ranged from 2 × 102 copies per ml to 4·78 × 108 copies per ml. HEV IgM/IgG antibodies were not detected in the RNA-positive patients. Sequencing analysis of HEV showed that the virus belongs to genotype 3 (HEV GT3). CONCLUSIONS: Real-time PCR was a useful tool to estimate co-infection with HEV/HIV, even in patients with low viral loads and undetectable anti-HEV IgG and IgM antibodies. SIGNIFICANCE AND IMPACT OF THE STUDY: Hepatitis E virus genotype 3 (HEV GT3) has been associated with silent chronic hepatitis and cirrhosis in HIV-positive subjects worldwide, but there is a lack of data on this co-infection in Brazil.


Asunto(s)
Infecciones por VIH/sangre , Anticuerpos Antihepatitis/sangre , Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/virología , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Adulto , Brasil , Coinfección/sangre , Coinfección/virología , Femenino , Genotipo , Infecciones por VIH/virología , Hepatitis E/sangre , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/inmunología , Virus de la Hepatitis E/fisiología , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Carga Viral
3.
Health Educ Res ; 33(4): 280-291, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29939230

RESUMEN

To identify the predictors of dropout in the 'Mexa-se' intervention according to the body mass index (BMI) category. This was a controlled, non-randomized study. The intervention included: (i) increase in the intensity of physical activities (PA) in physical education (PE) classes; (ii) active recess; (iii) educational sessions on PA, nutrition and body image; and (iv) educational materials. Dropout was considered when students dropped out of intervention, or did not reach 75% attendance in PE classes. The independent variables were gender, age, study period, socioeconomic status, BMI, PA, screen time, food consumption, health perception, attitudes toward PA, self-efficacy for PA, perception of the school environment, body image and self-esteem. Binary logistic regression analysis was used. The dropout rate was 26.8%. In the total sample and among students with an adequate BMI, there was a greater probability of dropout with an increase in age. For overweight students, increased age and socioeconomic status, and studying in the afternoon period were predictors of dropout from the intervention. Socio-demographic factors were predictors of dropout from the 'Mexa-se' intervention; the associated factors differed based on the BMI category.


Asunto(s)
Ejercicio Físico , Educación en Salud/organización & administración , Abandono Escolar/estadística & datos numéricos , Adolescente , Factores de Edad , Imagen Corporal , Índice de Masa Corporal , Niño , Dieta , Femenino , Humanos , Masculino , Educación y Entrenamiento Físico/organización & administración , Tiempo de Pantalla , Autoimagen , Factores Sexuales , Clase Social , Factores Socioeconómicos
4.
J Hum Nutr Diet ; 31(2): 276-285, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28799180

RESUMEN

BACKGROUND: Body composition analysis has been used to investigate fat mass (FM) and bone mineral content (BMC) in children and adolescents diagnosed with HIV. Investigating the validity of bioelectrical impedance analysis (BIA) is interesting with respect to testing useful techniques for monitoring body composition in children and adolescents in clinical practice. The present study aimed to determine the validity of body composition analysis by BIA compared to dual-energy X-ray absorptiometry (DXA) and air displacement plethysmography (ADP) in children and adolescents an HIV diagnosis. METHODS: Sixty-four children and adolescents (35 females and 29 males) with a mean (SD) age of 12.22 (2.13) years and with an HIV diagnosis participated in the study. Fat-free mass (FFM), FM and body fat percentage (%BF) were obtained by BIA for comparison with DXA and ADP. Segmented FM (trunk, legs and arms), lean soft tissue mass (LSTM) (total and segmented) and BMC were obtained by BIA for comparison with DXA. RESULTS: BIA presented a clinically acceptable correlation with DXA and ADP for FFM. Values found by BIA were underestimated compared to ADP, and overestimated compared to DXA. BIA presented a clinically acceptable correlation with DXA for LSTM estimates (total and segmented parameters) in both sexes (underestimating FM and overestimating LSTM). For other components (%BF, FM and BMC), BIA had a clinically unacceptable correlation with the reference methods in both sexes. CONCLUSIONS: BIA was suitable for evaluating FFM and LSTM in children and adolescents with an HIV diagnosis. For FM, %BF and BMC, BIA was not suitable for performing an evaluation in both sexes.


Asunto(s)
Absorciometría de Fotón , Composición Corporal , Compartimentos de Líquidos Corporales/metabolismo , Impedancia Eléctrica , Infecciones por VIH/complicaciones , Pletismografía , Tejido Adiposo/metabolismo , Adolescente , Índice de Masa Corporal , Densidad Ósea , Niño , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
5.
Genet Mol Res ; 16(3)2017 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-28973781

RESUMEN

This study aimed at identifying and selecting through partial diallel analysis, segregating populations of cowpea resistant to Macrophomina phaseolina and Thanatephorus cucumeris, based on the evaluation of general (GCA) and specific combining ability (SCA), involved in the genetic control of resistance. For this reason, 19 grouped cowpea genotypes, considering the resistance to these pathogens, were crossed in partial diallel scheme 14 x 5, during 2013 and 2014. The 70 F2 populations and the 19 parents were evaluated in a greenhouse as the reaction to pathogens, separately. The diallel analysis was performed according to the model of partial diallel proposed by Geraldi and Miranda Filho (1988). The additive effects predominated in the genetic control of the traits severity of charcoal rot (SEV) and area under the disease progress curve (AUDPC) to web blight, enabling the achievement of genetic gain with selection of resistant strains. Analyzing the effects of GCA, the parents BR 14-Mulato, BRS Tumucumaque and BRS Guariba, have a higher concentration of favorable alleles, highlighting, according to the values of SCA, the combinations BR 14-Mulato x MNC02-675F-4-10, BRS Tumucumaque x IT98K-1092-1, BRS Tumucumaque x MNC02-675F-4-10, BRS Tumucumaque x MNC02-675F-9-2, BRS Guariba x IT98K-1092-1, BRS Guariba x MNC02-675F-4-9, and BRS Guariba x MNC02-675F-4-10, as the most promising and indicated to obtain lines resistant to M. phaseolina and T. cucumeris in cowpea, simultaneously.


Asunto(s)
Resistencia a la Enfermedad/genética , Hibridación Genética , Selección Artificial , Vigna/genética , Alelos , Ascomicetos/patogenicidad , Basidiomycota/patogenicidad , Genotipo , Fitomejoramiento/métodos , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Vigna/inmunología , Vigna/microbiología
6.
Genet Mol Res ; 16(3)2017 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-28829904

RESUMEN

The aim of this study was to estimate the genotypic gain with simultaneous selection of production, nutrition, and culinary traits in cowpea crosses and backcrosses and to compare different selection indexes. Eleven cowpea populations were evaluated in a randomized complete block design with four replications. Fourteen traits were evaluated, and the following parameters were estimated: genotypic variation coefficient, genotypic determination coefficient, experimental quality indicator and selection reliability, estimated genotypic values ​​- BLUE, genotypic correlation coefficient among traits, and genotypic gain with simultaneous selection of all traits. The genotypic gain was estimated based on tree selection indexes: classical, multiplicative, and the sum of ranks. The genotypic variation coefficient was higher than the environmental variation coefficient for the number of days to start flowering, plant type, the weight of one hundred grains, grain index, and protein concentration. The majority of the traits presented genotypic determination coefficient from medium to high magnitude. The identification of increases in the production components is associated with decreases in protein concentration, and the increase in precocity leads to decreases in protein concentration and cooking time. The index based on the sum of ranks was the best alternative for simultaneous selection of traits in the cowpea segregating populations resulting from the crosses and backcrosses evaluated, with emphasis on the F4BC12, F4C21, and F4C12 populations, which had the highest genotypic gains.


Asunto(s)
Grano Comestible/genética , Endogamia , Modelos Genéticos , Fitomejoramiento/métodos , Selección Artificial , Vigna/genética , Grano Comestible/crecimiento & desarrollo , Grano Comestible/normas , Genotipo , Carácter Cuantitativo Heredable , Selección Genética , Vigna/crecimiento & desarrollo
7.
Genet Mol Res ; 15(4)2016 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-27808389

RESUMEN

Mouriri elliptica (Mart.) is a genetic resource of the Cerrado domain, which has potential for food and medicinal use. A few studies have been performed on its in vitro propagation, and no studies have examined dissimilarities between plants of this species when cultivated in situ or in vitro. Therefore, the objective of the present study was to identify in vitro cultivation conditions that permit the formation of plantlets with leaf anatomical features that are less dissimilar to those of plants grown in situ. Thus, an anatomical study of the leaves was conducted to investigate the adaxial epidermis thickness, abaxial epidermis thickness, chlorenchyma thickness, stomatal crypt depth, stomatal crypt density, and leaf surface stomatal crypt aperture area. The distance between phenotypes was determined based on micromorphometric data, and unweighted pair group mean arithmetic clustering was performed. Four different groups were tested, and cultivation with sucrose and 50 and 75 µmol⋅m-2⋅s-1 irradiance was found to promote plantlet development and maximize similarity to plants cultivated in situ. The most important anatomical parameters in this study were the stomatal crypt aperture area and the crypt density. This study is of importance for the anatomical characterization of M. elliptica (Mart.) leaves, as it identifies plasticity as a function of in vitro culture conditions.


Asunto(s)
Melastomataceae/anatomía & histología , Agricultura/métodos , Melastomataceae/crecimiento & desarrollo , Melastomataceae/metabolismo , Fenotipo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/crecimiento & desarrollo
8.
Bioprocess Biosyst Eng ; 39(8): 1201-11, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27126499

RESUMEN

Souring of oil fields during secondary oil recovery by water injection occurs mainly due to the action of sulfate-reducing bacteria (SRB) adhered to the rock surface in the vicinity of injection wells. Upflow packed-bed bioreactors have been used in petroleum microbiology because of its similarity to the oil field near the injection wells or production. However, these reactors do not realistically describe the regions near the injection wells, which are characterized by the presence of a saturated zone and a void region close to the well. In this study, the hydrodynamics of the two-compartment packing-free/packed-bed pilot bioreactor that mimics an oil reservoir was studied. The packed-free compartment was modeled using a continuous stirred tank model with mass exchange between active and stagnant zones, whereas the packed-bed compartment was modeled using a piston-dispersion-exchange model. The proposed model adequately represents the hydrodynamic of the packed-free/packed-bed bioreactor while the simulations provide important information about the characteristics of the residence time distribution (RTD) curves for different sets of model parameters. Simulations were performed to represent the control of the sulfate-reducing bacteria activity in the bioreactor with the use of molybdate in different scenarios. The simulations show that increased amounts of molybdate cause an effective inhibition of the souring sulfate-reducing bacteria activity.


Asunto(s)
Reactores Biológicos , Molibdeno/química , Sulfatos/metabolismo , Hidrodinámica , Modelos Teóricos , Oxidación-Reducción
9.
Bioprocess Biosyst Eng ; 36(12): 1861-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23636473

RESUMEN

The activity of anaerobic sulfate reduction was studied using sulfate-reducing bacteria isolated from the water produced from a Brazilian oil reservoir. The effects of the initial sulfate concentration on the anaerobic sulfate reduction and sulfide generation kinetics were investigated. The redox potential, the biomass solution content, and the sulfate and the sulfide solution content were measured. The results indicate that the sulfate conversion and the sulfide generation are both first-order processes for the initial sulfate concentration of 823, 1,282, and 1,790 mg/L. The results for the kinetic constants for the sulfate conversion indicate an inhibition with the enhancement of the initial sulfate solution content. The kinetic constants for the sulfide generation indicate that this reaction is almost independent of the initial sulfate solution content due to the presence of at least two in-series processes that are faster than the microbial conversion of the sulfate. The kinetic test using the water from an onshore oil field, with an initial sulfide content of 228 mg/L and sulfate content of 947 mg/L, shows a sulfate conversion of 50 % in 528 h. The kinetic modeling for the net content of sulfate and sulfide indicates that the sulfate conversion is slower for this water than for the deionized water tests; however, the sulfide formation has almost the same conversion velocity. The reactions are first order in both cases.


Asunto(s)
Sulfatos/metabolismo , Biomasa , Medios de Cultivo , Concentración de Iones de Hidrógeno , Cinética , Modelos Biológicos , Oxidación-Reducción , Soluciones
10.
Braz J Med Biol Res ; 55: e12376, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36629525

RESUMEN

The aim of our study was to validate the use of the standardized Radiological Society of North America (RSNA) reporting system in individuals with known lung cancer who presented to the emergency department with suspected COVID-19. We included patients aged 18 years or older from the Cancer Institute of the State of São Paulo (ICESP) with a confirmed diagnosis of lung cancer, admitted to the emergency department and undergoing chest computed tomography (CT) for suspicion of COVID-19. Comparison between SARS-CoV2 RT-PCR across RSNA categories was performed in all patients and further stratified by diagnosis of lung cancer progression. Among 58 individuals included in the analysis (65±9 years, 43% men), 20 had positive RT-PCR. Less than a half (43%) had no new lung findings in the CT. Positive RT-PCR was present in 75% of those with typical findings according to RSNA and in only 9% when these findings were classified as atypical or negative (P<0.001). Diagnostic accuracy was even higher when stratified by the presence or absence of progressive disease (PD). Extent of pulmonary inflammatory changes was strongly associated with higher mortality, reaching a lethality of 83% in patients with >25% of lung involvement and 100% when there was >50% of lung involvement. The lung involvement score was also highly predictive of prognosis in this population as was reported for non-lung cancer individuals. Collectively, our results demonstrated that diagnostic and prognostic values of chest CT findings in COVID-19 are robust to the presence of lung abnormalities related to lung cancer.


Asunto(s)
COVID-19 , Neoplasias Pulmonares , Masculino , Humanos , Femenino , COVID-19/diagnóstico por imagen , SARS-CoV-2 , ARN Viral , Brasil , Tomografía Computarizada por Rayos X/métodos , Neoplasias Pulmonares/diagnóstico por imagen , América del Norte/epidemiología , Estudios Retrospectivos
11.
Trop Biomed ; 38(3): 338-342, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34508341

RESUMEN

Leishmaniasis is a neglected and endemic disease that affects poorest population mainly in developing countries. Thymus provides an essential complex environment for T cell maturation and differentiation during leishmania infection. The aim of this study was to investigate the pathological alterations of the Thymus during early Leishmania amazonensis murine infection. BALB/c mice were infected with 105 amastigotes for 24 h, 3 days, 7 days, 15 days or 30 days. At different times of infection, the relative weight of the Thymus was obtained, and the Thymus cellularity was determined by counting total cells of one thymic lobe. The thymic lobe was, alternatively, processed for standard Haematoxylin and Eosin protocol. Our results suggest thymic alteration during the early days of BALB/c mice infection with L. amazonensis. The thymic hypertrophy was accompanied by histological alterations in Thymus architecture with thickening cortex at 3 days p.i. and loss of an evident delimitation between the cortex and medulla at 7 days p.i. when compared to the control mice. That is the first time that Thymus hypertrophy was observed during the early leishmaniasis. However, how it may contribute to infection susceptibility requires further investigation.


Asunto(s)
Leishmaniasis , Timo , Animales , Hipertrofia , Leishmania mexicana , Leishmaniasis/patología , Ratones , Ratones Endogámicos BALB C , Timo/parasitología , Timo/patología
12.
Pediatr Obes ; 15(6): e12623, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32050058

RESUMEN

BACKGROUND: Over the past three decades, the prevalence rate of overweight and obesity has increased in survivors with congenital heart disease, and little is known about the body composition and its association with clinical characteristics and lifestyle factors. OBJECTIVES: To evaluate excess total-body adiposity and central adiposity and, to describe associated factors. METHODS: Cross-sectional study with children and adolescents who underwent procedure to treat congenital heart disease, from January to July 2017. Sociodemographic and clinical characteristics, and lifestyle factors (dietary intake, physical activity, and sedentary behavior) were assessed. Adiposity was assessed using air-displacement plethysmography and waist circumference. Factors associated with excess total-body adiposity and central adiposity were analyzed using logistic regression models. RESULTS: Of 232 patients, 22.4% were identified with excess total-body adiposity and 24.6% with central adiposity. Significant factors positively associated with excess total-body adiposity were intake of added sugar and trans fatty acids, adjusted for confounding factors. Similarly, lifestyle factors were positively associated with central adiposity: intake of added sugar and trans fatty acids, sedentary behavior, and family history of obesity. CONCLUSIONS: Lifestyle factors were associated with excess total-body adiposity and central adiposity. Assessment of body composition and healthy-lifestyle counseling into outpatient care may be the key point to prevent obesity in children and adolescents with congenital heart disease.


Asunto(s)
Adiposidad , Cardiopatías Congénitas/metabolismo , Conducta Sedentaria , Azúcares/administración & dosificación , Ácidos Grasos trans/administración & dosificación , Adolescente , Índice de Masa Corporal , Niño , Estudios Transversales , Femenino , Cardiopatías Congénitas/complicaciones , Humanos , Estilo de Vida , Masculino , Obesidad Infantil/prevención & control
13.
MethodsX ; 6: 458-463, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30911470

RESUMEN

Souring in oil fields occurs mainly due to the activity of sulfate reducing bacteria (SRB). Most of the studies on SRB are performed using upflow packed-bed reactors that have a limitation to describe the region close to the injection wells in oil fields, which is characterized by void and saturated porous bed regions. Here, it is described the design and operation of a pilot scale system to investigate the SRB activity, inhibition and control in oil fields. •The bioreactor is composed by two-compartments (empty and packed-bed).•The reactor system has two parallel bioreactors that can be supplied with the same source of nutrients through a single pump or can be supplied separately with different solutions using two pumps.•The hydrodynamics for conventional packed bed bioreactors has a mixing behavior dependent of the flow rate and has a significant by-pass. In contrast, the two-compartment system presented here has a mixing behavior almost independent of the flow rate.

14.
Mem Inst Oswaldo Cruz ; 103(5): 463-7, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18797759

RESUMEN

Comparison of the use of indirect immunofluorescence assay (IFA), immunochromatography assay (ICA-BD) and reverse transcription-polymerase chain reaction (RT-PCR) for detecting human respiratory syncytial virus (HRSV) in 306 nasopharyngeal aspirates samples (NPA) was performed in order to assess their analytical performance. By comparing the results obtained using ICA-BD with those using IFA, we found relative indices of 85.0% for sensitivity and 91.2% for specificity, and the positive (PPV) and negative (NPV) predictive values were 85.0% and 91.2%, respectively. The relative indices for sensitivity and specificity as well as the PPV and NPV for RT-PCR were 98.0%, 89.0%, 84.0% and 99.0%, respectively, when compared to the results of IFA. In addition, comparison of the results of ICA-BD and those of RT-PCR yielded relative indices of 79.5% for sensitivity and 95.4% for specificity, as well as PPV and NPV of 92.9% and 86.0%, respectively. Although RT-PCR has shown the best performance, the substantial agreement between the ICA-BD and IFA results suggests that ICA-BD, also in addition to being a rapid and facile assay, could be suitable as an alternative diagnostic screening for HRSV infection in children.


Asunto(s)
Cromatografía , Técnica del Anticuerpo Fluorescente Indirecta , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Virus Sincitial Respiratorio Humano , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Enfermedad Aguda , Preescolar , Cromatografía/métodos , Humanos , Líquido del Lavado Nasal/virología , Nasofaringe/virología , Valor Predictivo de las Pruebas , ARN Viral/genética , Virus Sincitial Respiratorio Humano/genética , Virus Sincitial Respiratorio Humano/inmunología , Sensibilidad y Especificidad
15.
J Hazard Mater ; 150(3): 747-53, 2008 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-17583425

RESUMEN

The solid waste generated by artisanal gold mining, with high mercury and gold contents, can be found in several areas in the South America. The present study focused on the tailings of an artisanal gold mine area located in the Brazilian northeastern. Samples of the mine tailings were taken and used to perform a physical and chemical characterization study using X-ray diffraction, scanning electron microscopy, neutron activation, X-ray fluorescence, induced coupled plasma-mass spectrometry, among others analytical methods. The results indicate that the material is composed mainly by quartz and goethite, the characteristic size of the particles (d(50)) is about 150 microm, and the density is close of that of quartz. The main constituents are silicon, iron, and aluminum. The tailings gold content is of about 1.8 mg/kg and the mercury content is of about 10 mg/kg. A remarkable feature of this solid waste is that the gold and mercury are both concentrated in both the fine and the coarse particles, but not in particles of intermediary size. Leaching studies indicated that the tailings are stable in weak organic acids, but soluble in alkaline and aired cyanide solutions, in which 89% of gold and 100% of mercury are extracted in 24 h. Electroleaching experiments, performed using sodium chloride as electrolyte, indicated that mercury and gold are extracted simultaneously and the recovery of both metals can be as high as 70% in 4 h. In addition, chromium, nickel, and lead are found in relatively large amounts in the solution, which indicate an effectively action of the electroleaching method to clean up solid wastes contaminated with metals.


Asunto(s)
Oro , Residuos Industriales/análisis , Minería , Ácido Acético/química , Brasil , Cianuros/química , Electrólisis , Oro/análisis , Metales/análisis , Metales/química , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Difracción de Rayos X
17.
Braz. j. med. biol. res ; 55: e12376, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1420744

RESUMEN

The aim of our study was to validate the use of the standardized Radiological Society of North America (RSNA) reporting system in individuals with known lung cancer who presented to the emergency department with suspected COVID-19. We included patients aged 18 years or older from the Cancer Institute of the State of São Paulo (ICESP) with a confirmed diagnosis of lung cancer, admitted to the emergency department and undergoing chest computed tomography (CT) for suspicion of COVID-19. Comparison between SARS-CoV2 RT-PCR across RSNA categories was performed in all patients and further stratified by diagnosis of lung cancer progression. Among 58 individuals included in the analysis (65±9 years, 43% men), 20 had positive RT-PCR. Less than a half (43%) had no new lung findings in the CT. Positive RT-PCR was present in 75% of those with typical findings according to RSNA and in only 9% when these findings were classified as atypical or negative (P<0.001). Diagnostic accuracy was even higher when stratified by the presence or absence of progressive disease (PD). Extent of pulmonary inflammatory changes was strongly associated with higher mortality, reaching a lethality of 83% in patients with >25% of lung involvement and 100% when there was >50% of lung involvement. The lung involvement score was also highly predictive of prognosis in this population as was reported for non-lung cancer individuals. Collectively, our results demonstrated that diagnostic and prognostic values of chest CT findings in COVID-19 are robust to the presence of lung abnormalities related to lung cancer.

18.
Mater Sci Eng C Mater Biol Appl ; 68: 338-342, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27524028

RESUMEN

Layer-by-Layer (LbL) films containing silk fibroin (SF) and the 40 aminoacid-long amyloid-ß peptide (Aß1-40) were prepared with the purpose of developing a new prototype of an electrochemical immunosensor. The film showed a satisfactory growth in quartz substrate and screen-printed carbon electrodes, as observed by UV-vis spectroscopy and cyclic voltammetric, respectively. The peptide immobilized in LbL films in junction with SF shows secondary structure induced, as shown by circular dichroism measurements, favoring the interaction SF/peptide LbL film with the specific antibody. Immunosensor showed a linear response in the presence of the antibody with concentrations from 0 to 10ngmL(-1) both analyzed by current changes in 0.3V and voltammogram area. This system can be applied as a new prototype for preliminary diagnosis of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides/metabolismo , Anticuerpos/química , Técnicas Biosensibles/métodos , Fibroínas/química , Membranas Artificiales , Fragmentos de Péptidos/metabolismo , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/metabolismo , Animales , Humanos
19.
MethodsX ; 2: 249-55, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26150995

RESUMEN

The photometric determination of bacterial concentration can be affected by secondary scattering and other interferences. The conventional growth medium for sulfate-reducing bacteria (SRB) has iron that precipitates as iron sulfides, a dark precipitate which is useful to indicate bacterial activity. However, iron hydroxides also precipitate at high pH values and the presence of these precipitates interferes considerably in the optical density of the solution affecting estimates of the cell population thus seriously limiting the use of the conventional method. In this method a modification of the current method improves the measurement of the optical density of a solution with SRB cells. •The method consists of an acidification with hydrochloric acid of a sample of a mixed culture of SRB enriched from the produced water from oil fields to pH below 2.•The results show that the relationship between the bacterial dry mass and absorbance is exponential in the observed range. It was observed a large slope in the linearized fit equation, and the acidified solution does not change the integrity of the SRB cells after the treatment.•The results of the kinetic experiments, including the bacterial growth time evolution, demonstrate the applicability of the method.

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