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1.
Eur J Appl Physiol ; 120(6): 1227-1235, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32130484

RESUMEN

AIMS: Endurance athletes develop cardiac remodeling to cope with increased cardiac output during exercise. This remodeling is both anatomical and functional and shows large interindividual variability. In this study, we quantify local geometric ventricular remodeling related to long-standing endurance training and assess its relationship with cardiovascular performance during exercise. METHODS: We extracted 3D models of the biventricular shape from end-diastolic cine magnetic resonance images acquired from a cohort of 89 triathlon athletes and 77 healthy sedentary subjects. Additionally, the athletes underwent cardio-pulmonary exercise testing, together with an echocardiographic study at baseline and few minutes after maximal exercise. We used statistical shape analysis to identify regional bi-ventricular shape differences between athletes and non-athletes. RESULTS: The ventricular shape was significantly different between athletes and controls (p < 1e-6). The observed regional remodeling in the right heart was mainly a shift of the right ventricle (RV) volume distribution towards the right ventricular infundibulum, increasing the overall right ventricular volume. In the left heart, there was an increment of left ventricular mass and a dilation of the left ventricle. Within athletes, the amount of such remodeling was independently associated to higher peak oxygen pulse (p < 0.001) and weakly with greater post-exercise RV free wall longitudinal strain (p = 0.03). CONCLUSIONS: We were able to identify specific bi-ventricular regional remodeling induced by long-lasting endurance training. The amount of remodeling was associated with better cardiopulmonary performance during an exercise test.


Asunto(s)
Tolerancia al Ejercicio/fisiología , Ejercicio Físico/fisiología , Corazón/diagnóstico por imagen , Resistencia Física/fisiología , Remodelación Ventricular/fisiología , Adulto , Atletas , Ecocardiografía , Entrenamiento Aeróbico , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Adulto Joven
2.
Braz J Biol ; 76(1): 109-16, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26909629

RESUMEN

The objective of this study was to describe the embryonic and larval development of Brycon amazonicus, featuring the main events up to 50 hours after fertilization (AF). The material was provided by the Aquaculture Training, Technology and Production Center, Presidente Figueiredo (AM). The characterization was based on stereomicroscopic examination of the morphology of eggs, embryos and larvae and comparison with the literature. Matrinxã eggs are free, transparent, and spherical, with a perivitelline space of 0.56 ± 0.3 mm. The successive divisions give rise to cells with 64 blastomeres during the first hour AF. The gastrula stage, beginning 02 h 40 min AF, was characterized by progressive regression cells and the formation of the embryonic axis, leading to differentiation of the head and tail 05 h 30 min AF. From 06 to 09 h AF the somites, notochord, otic and optic vesicles and otoliths were observed, in addition to heart rate and the release of the tail. The larvae hatched at 10 h 30 min AF (29.9 °C), with a total length of 3.56 ± 0.46 mm. Between 19 and 30 h AF, we observed 1) pigmentation and gut formation, 2) branchial arches, 3) pectoral fins, 4) a mouth opening and 5) teeth. Cannibalism was initiated earlier (34 h AF) which was associated with rapid yolk absorption (more than 90% until 50 h AF), signaling the need for an exogenous nutritional source. The environmental conditions (especially temperature) influenced the time course of some events throughout the embryonic and larval development, suggesting the need for further studies on this subject.


Asunto(s)
Characidae/embriología , Characidae/crecimiento & desarrollo , Embrión no Mamífero/embriología , Desarrollo Embrionario , Animales
3.
Braz. j. biol ; 76(1): 109-116, Feb. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-774509

RESUMEN

Abstract The objective of this study was to describe the embryonic and larval development of Brycon amazonicus, featuring the main events up to 50 hours after fertilization (AF). The material was provided by the Aquaculture Training, Technology and Production Center, Presidente Figueiredo (AM). The characterization was based on stereomicroscopic examination of the morphology of eggs, embryos and larvae and comparison with the literature. Matrinxã eggs are free, transparent, and spherical, with a perivitelline space of 0.56 ± 0.3 mm. The successive divisions give rise to cells with 64 blastomeres during the first hour AF. The gastrula stage, beginning 02 h 40 min AF, was characterized by progressive regression cells and the formation of the embryonic axis, leading to differentiation of the head and tail 05 h 30 min AF. From 06 to 09 h AF the somites, notochord, otic and optic vesicles and otoliths were observed, in addition to heart rate and the release of the tail. The larvae hatched at 10 h 30 min AF (29.9 °C), with a total length of 3.56 ± 0.46 mm. Between 19 and 30 h AF, we observed 1) pigmentation and gut formation, 2) branchial arches, 3) pectoral fins, 4) a mouth opening and 5) teeth. Cannibalism was initiated earlier (34 h AF) which was associated with rapid yolk absorption (more than 90% until 50 h AF), signaling the need for an exogenous nutritional source. The environmental conditions (especially temperature) influenced the time course of some events throughout the embryonic and larval development, suggesting the need for further studies on this subject.


Resumo O objetivo deste trabalho foi descrever o desenvolvimento embrionário e larval do Brycon amazonicus, caracterizando os principais eventos ocorridos até 50 h Após Fertilização (AF). O material é proveniente do Centro de Treinamento, Tecnologia e Produção em Aqüicultura em Presidente Figueiredo (AM). A caracterização foi feita com base na análise estereomicroscópica da morfologia dos ovos, embriões e larvas e comparação bibliográfica. Os ovos da matrinxã são livres, transparentes, esféricos com espaço perivitelínico de 0,56 ± 0,3 mm. As sucessivas clivagens originam células com 64 blastômeros na primeira hora AF. A gástrula, iniciada 02 h e 40 min AF caracterizou-se por progressiva involução celular e formação do eixo embrionário, culminando com diferenciação de cabeça e cauda com 05 h 30 min AF. De 06 às 09h AF foi observada a formação de somitos, notocorda, vesículas óptica, ótica e otólitos, além de batimentos cardíacos e liberação da cauda. As larvas eclodiram com 10 h 30 min AF (29,9 °C), com 3,56 ± 0,46 mm de comprimento total. Entre 19 e 30 h AF foram observadas: 1) pigmentação e formação do tubo digestivo 2) surgimento de arcos branquiais 3) nadadeira peitoral 4) abertura da boca e 5) surgimento dos dentes. O canibalismo iniciou mais precocemente (34 h AF), em relação aos trabalhos existentes com o gênero, o que associado à rápida absorção do vitelo (mais de 90% até 50 h AF), sinaliza a necessidade de ofertar recurso alimentar exógeno. As condições ambientais (especialmente temperatura e pH) influenciaram na abreviação de alguns eventos ao longo do desenvolvimento embrionário e larval, sugerindo a necessidade de estudos complementares a esse respeito.


Asunto(s)
Animales , Characidae/embriología , Characidae/crecimiento & desarrollo , Desarrollo Embrionario , Embrión no Mamífero/embriología
4.
Rev. bras. plantas med ; 16(4): 826-831, oct.-dic. 2014. ilus, tab
Artículo en Portugués | LILACS | ID: lil-729890

RESUMEN

Tinturas preparadas com as folhas de Camellia sinensis (chá verde), foram caracterizadas visando a obtenção de extratos enriquecidos em polifenóis. As tinturas foram obtidas por meio de maceração estática da droga pulverizada, com diferentes misturas de 60, 70, 80 e 94,5% de etanol em água. Em seguida foram filtradas e, após 8 dias de extração, realizaram-se as analises: organoléptica, pH, densidade, determinação do resíduo seco, perfil cromatográfico por camada delgada, e teor de polifenóis. Os resultados demonstraram que o solvente (mistura hidroalcoólica a 60 ou 70%) extraiu a maior quantidade de constituintes químicos do chá verde; também foi o mais seletivo ao extrair, especificamente os polifenóis. Estes dados sugerem que a utilização de álcool etílico a 60 ou 70% conduz à obtenção de tinturas mais ricas em polifenóis, a partir das folhas do chá verde (C. sinensis).


In this work, we prepared and characterized Camellia sinensis leaf tinctures aiming to obtain a polyphenol-enriched extract. The tinctures were prepared through the static maceration process of the powdered drug, at different mixtures 60, 70, 80 and 94.5% of ethanol in water. The tinctures were filtered, and after 8 days of extraction, submitted to organoleptic analysis, determination of pH, density analysis, dry residue analysis, thin layer chromatographic profile and polyphenol percentage analysis. The results showed that the 60 or 70% alcohol-water mixture has the best extraction of the constituents of green tea and it was more selective to extract, specifically, the polyphenols of the plant. These data suggest the use of 60 or 70% ethanol to carry out polyphenol-enriched tinctures from green tea leaves (C. sinensis).


Asunto(s)
Té/clasificación , Tintura Madre , Camellia sinensis/metabolismo , Plantas Medicinales/clasificación , Control de Calidad , Extractos Vegetales/administración & dosificación , Polifenoles/análisis
6.
J Travel Med ; 10(3): 155-9, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12757689

RESUMEN

BACKGROUND: Misdiagnosis of imported malaria is not uncommon and even abnormal routine laboratory tests may not trigger malaria smears. However, blind screening of all thrombocytopenic samples might be a possible way to detect clinically unsuspected malaria cases in the accident and emergency department (AED). METHODS: The frequency and degree of thrombocytopenia was determined in two cohorts of malaria patients (Lisbon, Portugal and Berlin, Germany). The frequency of thrombocytopenia in full blood count (FBC) samples from patients presenting at the ED at a large teaching hospital in Lisbon, Portugal, was determined and compared with urgent samples from in-patients, both determined at a dedicated emergency laboratory. A cut-off value was established for screening of all FBC samples from the ED with Giemsa-stained thick-blood films. RESULTS: In 4,362 unselected samples from the ED in Lisbon a thrombocytopenia of <150,000/microL was found in 7% and of <100,000/microL in 2.2% of cases (2.5 samples/day with <100.000/microL). In patients with malaria, a thrombocytopenia was found in 75% and 77% (<150,000/microL) or 53% and 45% (<100,000/microL) in Lisbon, (n=60) and Berlin (n=170), respectively. Blind screening of all samples with <100,000 thrombocytes/microL by thick-blood film microscopy led to the diagnosis of 5 unsuspected malaria cases (3 Plasmodium falciparum, 1 Plasmodium vivax and 1 Plasmodium ovale), during the study. The diagnosis of each unsuspected malaria case would have cost 21 hours of dedicated technician's time. CONCLUSIONS: The problem of clinically unsuspected malaria seems to be more common than generally expected and is dependent on the local incidence of malaria as well as clinical and laboratory expertise. The blind screening of all thrombocytopenic samples with <100,000/microL may be a cost-effective way to reduce the misdiagnosis of imported malaria.


Asunto(s)
Errores Diagnósticos/prevención & control , Servicio de Urgencia en Hospital , Malaria/diagnóstico , Tamizaje Masivo/métodos , Trombocitopenia/diagnóstico , Adulto , África , Anciano , Berlin/epidemiología , Estudios de Cohortes , Humanos , Malaria/complicaciones , Persona de Mediana Edad , Portugal/epidemiología , Trombocitopenia/epidemiología , Trombocitopenia/etiología , Viaje
7.
Braz J Med Biol Res ; 29(5): 659-64, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-9033819

RESUMEN

We report the plasma levels of estradiol-17 beta (E2), testosterone (T), 17 alpha-20 beta-dihydroxy-4-pregnen-3-one (17-20P), and cortisol (F) in female pacu during the reproductive cycle (N = 44) and in females induced to ovulate with an analogue of luteinizing hormone releasing hormone (LHRHa; 10 micrograms/kg) (N = 24). The plasma hormone levels were determined by validated radioimmunoassays. Females sampled during the reproductive cycle were grouped into 4 gonadal stages: resting, early maturation, advanced maturation and regression. The calculated gonadosomatic index varied from 0.5 +/- 0.1% in resting stage to 8.1 +/- 0.6% in advanced maturation stage. The E2 and T values were highest during the early maturation stage (E2 = 2172 +/- 7.1 pg/ml; T = 412 +/- 58 pg/ml) and the F values were highest during the advanced maturation stage (132 +/- 5 ng/ml). Females induced to ovulate by LHRHa injection were sampled at 0.6, and 12 h after injection of LHRHa. Two additional groups were sampled at ovulation and 24 h after ovulation. The E2 values were highest at 6 h (2917 +/- 65 pg/ml). The T and F values were highest at ovulation (T = 3498 +/- 77 pg/ml; F = 387 +/- 16 ng/ml) and 17-20P was detected only at ovulation (2163 +/- 80 pg/ml).


Asunto(s)
Estradiol/sangre , Peces , Hormona Liberadora de Gonadotropina/análogos & derivados , Hidrocortisona/sangre , Inducción de la Ovulación , Testosterona/sangre , Análisis de Varianza , Animales , Femenino , Radioinmunoensayo , Sensibilidad y Especificidad
8.
Braz. j. med. biol. res ; 29(5): 659-64, May 1996. tab
Artículo en Inglés | LILACS | ID: lil-182552

RESUMEN

We report the plasma levels of estradiol-l7Beta (E2), testosterone (T), 17(alpha-2Obeta-dihydroxy-4-pregnen-3-one (l7-2OP), and cortisol (F) in female pacu during the reproductive cycle (N = 44) and in females induced to ovulate with an analogue of luteinizing hormone releasing hormone (LHRHa; 10 mug/kg) (N = 24). The plasma hormone levels were determined by validated radioimmunoassays. Females sampled during the reproductive cycle were grouped into 4 gonadal stages: resting, early maturation, advanced maturation and regression. The calculated gonadosomatic index varied from 0.5 ñ 0.1 per cent in resting stage to 8.1 ñ 0.6 per cent in advanced maturation stage. The E2 and T values were highest during the early maturation stage (E2 = 2172 ñ 7.1 pg/ml; T = 412 ñ 58 pg/ml) and the F values were highest during the advanced maturation stage (l32 ñ 5 ng/ml). Females induced to ovulate by LHRHa injection were sampled at 0, 6, and 12 h after injection of LHRHa. Two additional groups were sampled at ovulation and 24 h after ovulation. The E2 values were highest at 6 h (2917 + 65 pg/ml). The T and F values were highest at ovulation (T = 3498 + 77 pg/ml; F = 387 ñ 16 ng/ml) and 17-20P was detected only at vulation (2163 ñ 80 pg/ml).


Asunto(s)
Animales , Femenino , Estradiol/sangre , Peces , Hormona Liberadora de Gonadotropina/análogos & derivados , Hidrocortisona/sangre , Inducción de la Ovulación , Testosterona/sangre , Análisis de Varianza , Radioinmunoensayo , Sensibilidad y Especificidad
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