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1.
Appl Radiat Isot ; 187: 110314, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35714517

RESUMEN

This work presents neutron flux calculation results and specific decay heat and activity for the European DEMO reactor divertor structure. Two DEMO 2017 models were used in calculations; one with a homogenised WCLL breeder blanket and the other with a homogenised HCPB breeder blanket. The neutron flux calculations were performed using MCNP6 code with JEFF 3.2 nuclear data. Activation and decay heat calculations were performed using the FISPACT-II code with TENDL - 2017 nuclear data library.


Asunto(s)
Calor , Neutrones , Análisis por Activación , Radioisótopos
2.
Sci Rep ; 11(1): 14305, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34253797

RESUMEN

Nanofluids has broad applications such as emulsions, nuclear fuel slurries, molten plastics, extrusion of polymeric fluids, food stuffs, personal care products, shampoos, pharmaceutical industries, soaps, condensed milk, molten plastics. A nanofluid is a combination of a normal liquid component and tiny-solid particles, in which the nanomaterials are immersed in the liquid. The dispersion of solid particles into yet another host fluid will extremely increase the heat capacity of the nanoliquid, and an increase of heat efficiency can play a significant role in boosting the rate of heat transfer of the host liquid. The current article discloses the impact of Arrhenius activation energy in the bioconvective flow of Burger nanofluid by an inclined wall. The heat transfer mechanism of Burger nanofluid is analyzed through the nonlinear thermal radiation effect. The Brownian dispersion and thermophoresis diffusions effects are also scrutinized. A system of partial differential equations are converted into ordinary differential equation ODEs by using similarity transformation. The multi order ordinary differential equations are reduced to first order differential equations by applying well known shooting algorithm then numerical results of ordinary equations are computed with the help of bvp4c built-in function Matlab. Trends with significant parameters via the flow of fluid, thermal, and solutal fields of species and the area of microorganisms are controlled. The numerical results for the current analysis are seen in the tables. The temperature distribution increases by rising the temperature ratio parameter while diminishes for a higher magnitude of Prandtl number. Furthermore temperature-dependent heat source parameter increases the temperature of fluid. Concentration of nanoparticles is an decreasing function of Lewis number. The microorganisms profile decay by an augmentation in the approximation of both parameter Peclet number and bioconvection Lewis number.


Asunto(s)
Matemática , Modelos Teóricos , Análisis por Activación , Natación/fisiología
3.
J Gastroenterol Hepatol ; 35(8): 1381-1386, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32003069

RESUMEN

BACKGROUND AND AIM: Colonic perforation is a rare complication of colonoscopy and ranges from 0% to 1% in all patients undergoing colonoscopy. The aim of this study was to assess the time trends, risk factors, and mortality associated with colonoscopy-induced perforation (CIP) in hospitalized patients as the data are limited. METHODS: Data are obtained from the Nationwide Inpatient Sample database to identify hospitalized patients between 2005 and 2014 that had CIP. Various factors like age and gender were assessed for association with CIP, followed by univariate and multivariate regression analyses. RESULTS: A total of 2 651 109 patients underwent inpatient colonoscopy between 2005 and 2014, and 4567 (0.2%) of the patients had CIP. Overall, incidence of CIP has increased from 2005 to 2014 (0.1% to 0.3%) (P < 0.001). On multivariate analysis, the adjusted odds ratio (OR) for CIP was highest in Caucasian race (OR: 1.49 [1.09, 2.06]), followed by after polypectomy, history of inflammatory bowel disease, end-stage renal disease, and age > 65 years (OR [95% CI] of 1.35 [1.23, 1.47], 1.34 [1.17, 1.53], 1.28 [1.02, 1.62], and 1.21 [1.11, 1.33], respectively) (all P < 0.05). CIP group had 33% less obesity (OR [95% CI]: 0.77 [0.65-0.9], P = 0.002) and 13-fold higher mortality (0.5% vs 8.1%) (P < 0.001) as compared to patients without CIP. The CIP-associated mortality ranged from 2% to 8% and remained stable throughout the study period. CONCLUSIONS: Our study suggests that the risk of CIP was highest in elderly patients, Caucasians, those with inflammatory bowel disease, end-stage renal disease, and after polypectomy. Recognizing the factors associated with CIP may lead to informed discussion about risks and benefits of inpatient colonoscopy.


Asunto(s)
Colonoscopía/efectos adversos , Pacientes Internos/estadística & datos numéricos , Perforación Intestinal/etiología , Perforación Intestinal/mortalidad , Análisis por Activación , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Interpretación Estadística de Datos , Femenino , Humanos , Enfermedades Inflamatorias del Intestino , Perforación Intestinal/epidemiología , Pólipos Intestinales/cirugía , Fallo Renal Crónico , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Población Blanca , Adulto Joven
4.
J Appl Oral Sci ; 28: e20190266, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31800877

RESUMEN

OBJECTIVE: The microbial composition of pericoronitis (Pc) is still controversial; it is not yet clear if the microbial profile of these lesions is similar to the profile observed in periodontitis (Pd). Therefore, the aim of the present study was to describe the microbial profile of Pc lesions and compare it directly with that of subjects with Pd. METHODOLOGY: Subjects with Pc and Pd were selected, and subgingival biofilm samples were collected from (i) third molars with symptomatic Pc (Pc-T), (ii) contralateral third molars without Pc (Pc-C) and (iii) teeth with a probing depth >3 mm from subjects with Pd. Counts and proportions of 40 bacterial species were evaluated using a checkerboard DNA-DNA hybridization technique. RESULTS: Twenty-six patients with Pc and 18 with Pd were included in the study. In general, higher levels of microorganisms were observed in Pd. Only Actinomyces oris and Eubacterium nodatum were present in higher mean counts in the Pc-T group in comparison with the Pc-C and Pd-C groups (p<0.05). The microbiota associated with Pc-T was similar to that found in Pc-C. Sites with Pc lesions had lower proportions of red complex in comparison with the Pd sites. CONCLUSION: The microbiota of Pc is very diverse, but these lesions harbour lower levels of periodontal pathogens than Pd.


Asunto(s)
Bacterias/aislamiento & purificación , Pericoronitis/microbiología , Periodontitis/microbiología , Análisis por Activación , Adulto , Anciano , Carga Bacteriana , Biopelículas , Estudios Transversales , Sondas de ADN , Femenino , Encía/microbiología , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Adulto Joven
5.
J. appl. oral sci ; 28: e20190266, 2020. graf
Artículo en Inglés | LILACS, BBO | ID: biblio-1056586

RESUMEN

Abstract Objective: The microbial composition of pericoronitis (Pc) is still controversial; it is not yet clear if the microbial profile of these lesions is similar to the profile observed in periodontitis (Pd). Therefore, the aim of the present study was to describe the microbial profile of Pc lesions and compare it directly with that of subjects with Pd. Methodology: Subjects with Pc and Pd were selected, and subgingival biofilm samples were collected from (i) third molars with symptomatic Pc (Pc-T), (ii) contralateral third molars without Pc (Pc-C) and (iii) teeth with a probing depth >3 mm from subjects with Pd. Counts and proportions of 40 bacterial species were evaluated using a checkerboard DNA-DNA hybridization technique. Results: Twenty-six patients with Pc and 18 with Pd were included in the study. In general, higher levels of microorganisms were observed in Pd. Only Actinomyces oris and Eubacterium nodatum were present in higher mean counts in the Pc-T group in comparison with the Pc-C and Pd-C groups (p<0.05). The microbiota associated with Pc-T was similar to that found in Pc-C. Sites with Pc lesions had lower proportions of red complex in comparison with the Pd sites. Conclusion: The microbiota of Pc is very diverse, but these lesions harbour lower levels of periodontal pathogens than Pd.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Pericoronitis/microbiología , Periodontitis/microbiología , Bacterias/aislamiento & purificación , Valores de Referencia , Análisis por Activación , Sondas de ADN , Estudios Transversales , Biopelículas , Carga Bacteriana , Encía/microbiología
6.
Rev. bras. anal. clin ; 50(4): 365-370, 20190410. Tab.
Artículo en Portugués | LILACS | ID: biblio-995991

RESUMEN

O laboratório clínico tem a responsabilidade e compromisso de assegurar que os resultados dos exames reflitam de forma fidedigna a situação clínica apresentada pelos pacientes, por isso é necessário a implantação de um sistema da qualidade e a busca por um certificado de acreditação. O presente trabalho tem como principal objetivo analisar os processos da fase pré-analítica, analítica e pós-analítica em relação aos critérios estabelecidos na metodologia ONA e na norma PALC, identificando as melhores práticas para elaborar um projeto de implantação de um sistema de gestão de qualidade em um laboratório de análises clínicas através de uma análise comparativa com os processos do laboratório clínico. A metodologia usada foram pesquisas em bibliografias especializadas nas plataformas SciELO, PubMed, Lilacs e livros para avaliar a implantação de um sistema de qualidade no laboratório de análises clínicas. Como resultados após comparação das metodologias ONA e PALC, definimos a PALC como a melhor metodologia para o laboratório de análises clínicas, mostrando as ações necessárias para garantir que o processo seja realizado de forma correta.


Asunto(s)
Humanos , Organización y Administración , Análisis por Activación , Gestión de la Calidad Total
7.
Belo Horizonte; s.n; 2015. 124 p. tab, ilus.
Tesis en Portugués | LILACS, BDENF | ID: biblio-831461

RESUMEN

A infecção subclínica pode ser avaliada por meio de teste sorológico, que determina imunoglobulinas circulantes. O objetivo do presente estudo foi analisar a reatividade de diferentes antígenos em casos novos de hanseníase, contatos domiciliares de casos e em população de área endêmica, com o intuito de identificar o melhor antígeno para o diagnóstico sorológico da hanseníase e detecção de indivíduos infectados pelo Mycobacterium leprae.Trata-se de um estudo transversal de natureza exploratória e analítica. A reatividade anti-LID-1, NDO-LID, NDO-HSA e PGL-1 foi avaliada por meio do enzyme-linked immunosorbentassay. Foram analisadas amostras de sangue total em papel de filtro Whatman de 2494indivíduos da população de sete municípios da microrregião de Almenara e de soro de 94casos novos de hanseníase e 104 contatos domiciliares de casos residentes no município de Uberlândia. O Banco de Dados foi criado no Software Epi Info versão 3.5.1 e análise realizada no software Statistical Package for the Social Sciences for Windows 18 e no GraphPad Prism versão 5. Para análise estatística foram utilizados os seguintes testes: Kolmogorov-Smirnov, Kruskal-Wallis one-way (H), Mann-Whitney (U) com correção de Bonferroni, kappa, Spearman (rho), teste Qui-quadrado de Pearson e regressão logística binária. Foi observado maior soropositividade no grupo de casos multibacilares (MB), em contatos domiciliares de casos MB e nos indivíduos residentes nos municípios de Almenara e Jequitinhonha. Obteve-se correlação positiva entre a sorologia e o índice baciloscópico,concordância substancial e significativa no grupo de casos novos de hanseníase e correlação positiva para todos os antígenos testados. Os testes anti-LID-1 e anti-NDO-LID apresentaram melhor performance para identificar os contatos domiciliares e ou indivíduos da população...


The subclinical infection can be evaluated by serologic test which determine circulating immunoglobulins. The aim of this study was to analyze the reactivity of different antigens inleprosy cases, household contacts of index cases and the population of the endemic area toidentify the best antigen for the diagnosis of leprosy and detection of individuals infected with Mycobacterium leprae. It is a cross-sectional study of exploratory and analytical nature. There activity anti-LID-1, NDO-LID, NDO-HAS e PGL-1 were evaluated using the enzyme linke dimmunosorbent assay. The whole blood in What man filter paper of 2494 individuals from the general population of seven municipalities in the micro-Almenara and serum of 94 patients with leprosy and 104 household contacts of patients residing in Uberlândia were analyzed. The database was created in Epi Info software version 3.5.1 and analysis in the software Statistical Package for Social Sciences for Windows 18 and GraphPad Prism version5. For statistical analysis the following tests were used: Kolmogorov-Smirnov, Kruskal Wallisone-way (H), Mann-Whitney (U) with Bonferroni correction, kappa, Spearman (rho), chisquaretest of Pearson and binary logistic regression. Identied higher seropositivity in the group of MB patients, household contacts of MB patients and in individuals living in the municipalities of Almenara and Jequitinhonha. Observed positive correlation between serology test and bacterial index, substantial agreement and significant in patients positive and positive correlation for all antigens. The LID-1 and NDO-LID antigens showed greater ability to identify household contacts or the general population infected with M. leprae, but the performance of the NDO-LID was better. The native PGL-1 had higher seropositivity than the NDO-HSA for all clinical forms of leprosy and household contacts. The seropositivity prevalence in the general population was higher than the detection rate of leprosy...


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto Joven , Persona de Mediana Edad , Lepra/diagnóstico , Mycobacterium leprae , Análisis por Activación/instrumentación , Estudios Transversales/métodos , Factores Socioeconómicos , Lepra/epidemiología , Pruebas Serológicas/instrumentación
8.
Anal Bioanal Chem ; 404(6-7): 1887-95, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22918535

RESUMEN

Boron determination in blood and tissue samples is a crucial task especially for treatment planning, preclinical research, and clinical application of boron neutron capture therapy (BNCT). Comparison of clinical findings remains difficult due to a variety of analytical methods, protocols, and standard reference materials in use. This paper addresses the comparability of inductively coupled plasma mass spectrometry, quantitative neutron capture radiography, and prompt gamma activation analysis for the determination of boron in biological samples. It was possible to demonstrate that three different methods relying on three different principles of sample preparation and boron detection can be validated against each other and yield consistent results for both blood and tissue samples. The samples were obtained during a clinical study for the application of BNCT for liver malignancies and therefore represent a realistic situation for boron analysis.


Asunto(s)
Análisis por Activación/métodos , Boro/sangre , Espectrometría de Masas/métodos , Radiografía/métodos , Rayos gamma , Humanos
10.
Appl Radiat Isot ; 69(8): 1138-42, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21129990

RESUMEN

In this work a compact system was designed for bulk sample analysis using the technique of PGNAA. The system consists of (252)Cf fission neutron source, a moderator/reflector/filter assembly, and a suitable enclosure to delimit the resulting neutron beam. The moderator/reflector/filter arrangement has been optimised to maximise the thermal neutron component useful for samples analysis with a suitably low level of beam contamination. The neutron beam delivered by this compact system is used to irradiate the sample and the prompt gamma rays produced by neutron reactions within the sample elements are detected by appropriate gamma rays detector. Neutron and gamma rays transport calculations have been performed using the Monte Carlo N-Particle transport code (MCNP5).


Asunto(s)
Rayos gamma , Método de Montecarlo , Análisis de Activación de Neutrones/instrumentación , Análisis por Activación/instrumentación , Californio , Neutrones , Espectrometría gamma/métodos
11.
Appl Radiat Isot ; 68(1): 23-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19804983

RESUMEN

Lanthanides represent an interesting group of elements which are steadily gaining importance in science and in industry. Literature data suggest that they may have a role in regulating cellular processes and also in agriculture enhancing plant growth. Only few instrumental methods like NAA, ICP-OES and ICP-MS have potential for the determination of low levels of all lanthanides, but in practice they often have to be combined with suitable separation/preconcentration methods to achieve maximum number of elements being determined and to assure good accuracy and precision. In this work an attempt has been made to compare the performance of both variants of NAA: purely instrumental activation analysis (INAA) and radiochemical mode (RNAA) with pre- and post-irradiation group separation for the determination of individual lanthanides with the special emphasis on rarely determined elements (Gd, Ho, Er, Tm, Lu). This has been done by the analysis of two reference materials with different matrices viz. biological (CTA-OTL-1) and mineral (CTA-FFA-1). The results are compared with those obtained by ion chromatography (IC) employing the same lanthanide group preseparation scheme as in the case of RNAA.


Asunto(s)
Análisis por Activación/métodos , Elementos de la Serie de los Lantanoides/análisis , Elementos de la Serie de los Lantanoides/aislamiento & purificación , Cromatografía , Plantas/química
12.
J Acoust Soc Am ; 125(6): 4023-33, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19507983

RESUMEN

This study assessed the effects of spectral smearing and temporal fine structure (TFS) degradation on masking release (MR) (the improvement in speech identification in amplitude-modulated compared to steady noise observed for normal-hearing listeners). Syllables and noise stimuli were processed using either a spectral-smearing algorithm or a tone-excited vocoder. The two processing schemes simulated broadening of the auditory filters by factors of 2 and 4. Simulations of the early stages of auditory processing showed that the two schemes produced comparable excitation patterns; however, fundamental frequency (F0) information conveyed by TFS was degraded more severely by the vocoder than by the spectral-smearing algorithm. Both schemes reduced MR but, for each amount of spectral smearing, the vocoder produced a greater reduction in MR than the spectral-smearing algorithm, consistent with the effects of each scheme on F0 representation. Moreover, the effects of spectral smearing on MR produced by the two schemes were different for manner and voicing. Finally, MR data for listeners with moderate hearing loss were well matched by MR data obtained for normal-hearing listeners with vocoded stimuli, suggesting that impaired frequency selectivity alone may not be sufficient to account for the reduced MR observed for hearing-impaired listeners.


Asunto(s)
Enmascaramiento Perceptual , Percepción del Habla , Estimulación Acústica , Análisis por Activación , Adulto , Algoritmos , Simulación por Computador , Pérdida Auditiva/psicología , Humanos , Persona de Mediana Edad , Modelos Teóricos , Pruebas Neuropsicológicas , Ruido , Fonética , Habla , Acústica del Lenguaje , Análisis y Desempeño de Tareas , Factores de Tiempo , Adulto Joven
13.
J. appl. oral sci ; 16(3): 189-193, May-June 2008. ilus, tab
Artículo en Inglés | LILACS, BBO | ID: lil-483152

RESUMEN

The purpose of this study was to evaluate the Knoop hardness of a dual-cured resin-based luting cement irradiated with different light sources as well energy density through a ceramic sample. Three light-curing unit (LCUs) were tested: tungsten halogen light (HAL), light-emitting diode (LED) and xenon plasma-arc (PAC) lamp. Disc-shaped specimens were fabricated from a resin-based cement (Enforce). Three energy doses were used by modifying the irradiance (I) of each LCU and the irradiation time (T): 24 Jcm-2 (I/2x2T), 24 Jcm-2 (IxT) and 48 Jcm-2 (Ix2T). Energy doses were applied through a 2.0-mm-thick ceramic sample (Duceram Plus). Three groups underwent direct irradiation over the resin cement with the different LCUs and a chemically-activated group served as a control. Thirteen groups were tested (n=10). Knoop hardness number (KHN) means were obtained from cross-sectional areas. Two-way ANOVA and the Holm-Sidak method were used for statistical comparisons of activation mode and energy doses (á=5%). Application of 48 J.cm-2 energy dose through the ceramic using LED (50.5±2.8) and HAL (50.9±3.7) produced significantly higher KHN means (p<0.05) than the control (44.7±3.8). LED showed statistically similar performance to HAL. Only HAL showed a relationship between the increase of LCU energy dose and hardness increase.


Asunto(s)
Materiales Dentales , Pruebas de Dureza , Cementos de Resina , Análisis por Activación
14.
Acta amaz ; 37(3): 425-430, 2007. tab
Artículo en Portugués | LILACS | ID: lil-474442

RESUMEN

Considerando a ampla variabilidade genética de cubiu (Solanum sessiliflorum Dunal), quantificaram-se os macro e micro-nutrientes, objetivando a ampliação da tabela de composição química de alimentos típicos da região amazônica. Os frutos provenientes da Estação Experimental de Hortaliças Alejo von der Pahlen (EEH) do Instituto Nacional de Pesquisas da Amazônia (INPA), localizados no km 14 da Rodovia AM 010 em Manaus, AM, foram processados no Laboratório de Alimentos e Nutrição do INPA. Avaliaram-se oito etnovariedades de cubiu identificados como: 2 I, 3 I, 6, 7, 12, 14, 17, 29 I e III em estádio de maturação comercial. Os teores de elementos minerais foram quantificados pela técnica de Ativação por Nêutrons Instrumental e a fibra alimentar pelo método enzímico-gravimétrico. Os resultados demonstram ser o cubiu um fruto com baixo conteúdo energético (média de 33 kcal), com conteúdo de fibra alimentar total na ordem de 1,6 por cento. Em relação aos macros elementos minerais, a etnovariedade 6, apresentou a maior concentração em potássio (513,5±3,1mg), cálcio (18,9±0,6mg) e a etnovariedade 2 I em Fe (564,4±58,1µg) e Cr (99,3±8,3µg). A menor concentração foi constatada na etnovariedade 12 para os elementos K (229,0±4,5mg), Na (53,7±5,5µg) e Zn (89,3±4,7µg). Apesar das variações em relação as diferentes etno variedades e conseqüentemente concentrações em elementos minerais, o cubiu, pode estar contribuindo para atingir as recomendações desses nutrientes.


Considering the wide genetic variability of cubiu (Solanum sessiliflorum Dunal), its chemical composition was quantified in order to contribute to the chemical composition table of typical Amazonian foods. The cubiu fruit was collected at Alejo von der Pahlen (EEH) experimental station from National Research Institute of Amazonia (INPA). Eight ethno varieties of cubiu identified as 2 I, 3 I, 6, 7, 12, 14, 17, 29 I and III were analyzed. All samples used were ripe. The mineral content was determined by Neutron Activation Analysis technique and alimentary fiber by the enzymatic-gravimetric method. The results showed that cubiu is a hypo caloric food source (mean of 33 kcal and total fiber of about 1.6 percent). Regarding macronutrients, ethnovariety 6 showed high potassium (513.5 ± 3.1 mg) and calcium (18.8 ± 0.6 mg) concentration. Ethnovariety 21, had high Fe (564 ± 58 µg) and Cr (99 ± 8 µg) concentrations. Low concentrations of K (229.0 ± 4.5 mg), Na (53.7 ± 5.5 µg) and Zn (89.3 ± 4.7 µg) were found for ethnovariety 12. Although the cubiu fruit presents great variation of its mineral contents due to different ethnovarieties, it could still contribute as a diet supplement to reach the minimum nutrient requirements for the Amazonian population.


Asunto(s)
Análisis por Activación , Solanum , Minerales , Análisis de Activación de Neutrones
15.
J Alzheimers Dis ; 10(1): 81-7, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16988485

RESUMEN

Glutamate toxicity through NMDA receptor channels has long been central to the understanding of acute neuronal injury. Recent studies implicate similar events in chronic neurodegenerative diseases. Here, we analyze some of the most intriguing evidence for NMDA receptor-mediated cellular dysfunction and propose a mechanism by which hyperactive NMDA receptors might lead to neurofibrillary degeneration in Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Receptores de N-Metil-D-Aspartato/fisiología , Proteínas tau/metabolismo , Análisis por Activación/métodos , Enfermedad de Alzheimer/tratamiento farmacológico , Antiparkinsonianos/farmacología , Antiparkinsonianos/uso terapéutico , Humanos , Memantina/farmacología , Memantina/uso terapéutico , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Proteínas tau/efectos de los fármacos
16.
Acta amaz ; 33(4): 549-554, Dec. 2003. tab
Artículo en Portugués | LILACS | ID: lil-574673

RESUMEN

O camu-camu, caçari, ou araçá d'água (Myrciaria dubia (H.B.K) McVaugh) é um arbusto da família Myrtaceae, disperso em quase toda a Amazônia. É uma espécie tipicamente silvestre mas com grande potencial econômico e nutricional. Entretanto, no que se refere a elementos minerais, poucas informações são disponíveis na literatura. Considerando a essencialidade dessas informações na nutrição humana e objetivando contribuir na elaboração de uma Tabela de composição de alimentos a nível regional e nacional, determinou-se os elementos minerais em algumas populações de camu-camu, pela Técnica de Ativação com Nêutrons Instrumental. Verificou-se que em relação aos macro elementos minerais, nos frutos de camu-camu analisados, as maiores concentrações foram para potássio, com uma variação de (62,6±0,4 a 144,1±08 mg por cento) e cálcio (9,5±0,3 a 10,6±0,5 mg por cento). A concentração de sódio nos frutos foi baixa (90,7±16,5 µg por cento). A população Uatumã-9 apresentou maiores concentrações de zinco (472,0±8,3µg por cento), molibdênio (6,2±0,6µg por cento) e cromo (19,9±1,7 µg por cento), seguida da população Uatumã 24 em cobalto (2,4±0,03 mg por cento). Dessa forma, o consumo de camu-camu pode contribuir para atingir a ingestão adequada das recomendações de elementos minerais nos diferentes grupos populacionais da região Amazônica.


Camu-camu, caçari, or araçá d'água (Myrciaria dubia (H.B.K.) McVaugh) is a shrub of the Myrtaceae family, dispersed through almost all the Amazonia. It is a typically wild species but with great economic and nutritional potential. However, few information on its mineral content is available in the literature. Considering the importance of these information for the human nutrition, and, objectiving to contribute in the elaboration of a Table of food composition the regional and national level, was determined the mineral elements in some populations of camu-camu, by neutron activation analysis. According to the results, the greater concentrations was verified in relation to the macro mineral elements potassium, with a variation of (62,6±0,4 to 144,1±8,3 mg percent) and calcium (9,5±0,3 to 10,6±0,5 mg percent). The concentration of sodium in the fruts was low (19,9±1,7µg percent). The population Uatumã 9 presented greater concentrations of zinc (472,0±8,3µg percent), molybdenum (6,2±0,6µg percent) and chromium (19,9±1,7µg percent) followed of the population Uatumã 24 for cobalt (2,4±28,7mg percent). Therefore, camu-camu can contribute for reaching the recommendations of mineral elements intakes by the different human populations of the Amazon region.


Asunto(s)
Árboles , Análisis por Activación , Minerales
17.
J Cardiovasc Electrophysiol ; 12(8): 893-9, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11513439

RESUMEN

INTRODUCTION: Activation of the left atrium (LA) in patients with isthmus-dependent right atrial flutter (AFL) has not yet been studied. The aim of this study was to analyze the activation patterns in the LA in patients with counterclockwise and clockwise AFL. METHODS AND RESULTS: The study population consisted of 12 patients (10 men and 2 women; mean age 61+/-13 years) with documented AFL and atrial fibrillation referred for ablation. The LA was mapped with a 64-electrode basket catheter inserted through a transseptal approach (10 patients) or an open foramen ovale (2 patients). In patients with counterclockwise AFL (10 episodes), the LA was activated for a mean of 133+/-28 msec. Two endocardial breakthroughs of earliest activity on the left side of the interatrial septum, separated in time by an interval of 38+/-15 msec, were observed in 9 episodes (90%). Two wavefronts originated from these breakthroughs, which activated the posterior and the anterior LA walls, respectively. In one patient, the entire LA was activated from the inferior breakthrough. In patients with clockwise AFL (five episodes), the LA activation time was 130+/-13 msec. During ongoing episodes, two early electrical breakthroughs, separated in time by an interval of 41+/-15 msec, appeared in the high anteroseptal and low posteroseptal LA regions. The superior wavefront that emerged from the high anterolateral LA region was the dominant activation pathway in 4 (80%) of 5 episodes. CONCLUSION: In patients with AFL, the LA is activated by two wavefronts originating from the high anterior and the low posterior regions of the interatrial septum. The sequence of activation of these interatrial connections in counterclockwise or clockwise AFL and the conductive properties of the LA conduction pathways determine the activation patterns in the LA.


Asunto(s)
Análisis por Activación , Aleteo Atrial/fisiopatología , Atrios Cardíacos/fisiopatología , Anciano , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/cirugía , Aleteo Atrial/cirugía , Ablación por Catéter , Estimulación Eléctrica , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Femenino , Sistema de Conducción Cardíaco/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo
18.
Fresenius J Anal Chem ; 370(2-3): 241-5, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11451244

RESUMEN

The capabilities of neutron and photon activation analysis (NAA and PAA, respectively) for low-level determination of silicon in biological materials have been examined. Sensitivities of a variety of modes of NAA and PAA with radiochemical separation have been evaluated. Results are presented for silicon in reference materials CSRM 12-2-03 Lucerne, Bowen's Kale, NIST SRM-1571 Orchard Leaves, and NIST SRM-1515 Apple Leaves. The results were obtained by employing the 29Si(n,p)29Al reaction with fast reactor neutrons and the radiochemical procedure developed for aluminium separation. Possibilities of further improvement of the silicon determination limit down to the microg g(-1) level by employing NAA and PAA with radiochemical separation are outlined.


Asunto(s)
Análisis por Activación/métodos , Silicio/análisis , Aluminio/aislamiento & purificación , Animales , Isótopos , Hígado/química , Análisis de Activación de Neutrones , Fotones , Plantas/química , Radioquímica/métodos , Radioisótopos , Estándares de Referencia , Porcinos
19.
J Cardiovasc Electrophysiol ; 12(5): 511-7, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11386509

RESUMEN

INTRODUCTION: It often is difficult to determine the optimal ablation site for idiopathic ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) when the VT or premature ventricular complex (PVC) does not occur frequently. The aim of our study was to evaluate the usefulness of a multielectrode basket catheter for ablation of idiopathic VT originating from the RVOT. METHODS AND RESULTS: Radiofrequency (RF) catheter ablation was performed using a 4-mm tip, quadripolar catheter in 50 consecutive patients with 81 VTs originating from the RVOT with (basket group = 25 patients with 45 VTs) or without (control group = 25 patients with 36 VTs) predeployment of a multielectrode basket catheter composed of 64 electrodes. Deployment of the multielectrode basket catheter was possible and safe in all 25 patients in the basket group. Ablation was successful in 25 (100%) of 25 patients in the basket group and in 22 (88%) of 25 patients in the control group. The total number of RF applications and the number of RF applications per PVC morphology did not differ between the two groups. However, both the fluoroscopic and ablation procedure times per PVC morphology were shorter in the basket group than in the control group (36.8+/-14.1 min vs 52.0+/-32.5 min, P = 0.04; 60.0+/-14.6 vs 81.5+/-51.2 min, P = 0.05). This difference was more pronounced in the 29 patients in whom VT or PVC was not frequently observed. CONCLUSION: The multielectrode basket catheter is safe and useful for determining the optimal ablation site in patients with idiopathic VT originating from the RVOT, especially in those without frequent VT or PVC.


Asunto(s)
Ablación por Catéter/instrumentación , Ventrículos Cardíacos/patología , Ventrículos Cardíacos/cirugía , Taquicardia Ventricular/patología , Taquicardia Ventricular/cirugía , Análisis por Activación/instrumentación , Adulto , Electrocardiografía/instrumentación , Femenino , Fluoroscopía , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Taquicardia Ventricular/etiología , Factores de Tiempo , Obstrucción del Flujo Ventricular Externo/complicaciones , Obstrucción del Flujo Ventricular Externo/cirugía , Complejos Prematuros Ventriculares/complicaciones , Complejos Prematuros Ventriculares/cirugía
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