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1.
Braz J Biol ; 84: e260650, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35674587

RESUMEN

With increased interest in cultivation, the study of white-fleshed pitahaya (Selenicereus undatus (Haw.) D.R. Hunt, Cactaceae family) seedling production is of fundamental importance in the search for novel techniques to increase cultivation and guarantee homogeneous and productive orchards. The present study investigated the influence of various gibberellic acid (GA3) concentrations and fruit maturation stages on seed germination and vigor of white-fleshed pitahaya seedlings, considering the physiological quality of seedlings produced to support genetic breeding and conservation programs of the species. White-fleshed pitahaya seeds at two maturation stages (physiologically ripe and maintained at 10 °C in Biochemical Oxygen Demand incubators for three months) were treated with varying GA3 concentrations of 0, 50, 100, and 500 mg/L. We observed the influence of fruit storage on seedling germination, emergence, and growth as a function of GA3 concentration. According to the results, seeds extracted from ripe white-fleshed pitahaya fruits grown under the conditions tested here required GA3 application to increase seedling emergence and vigor, with optimal doses in the 150-300-mg/L range. In the case of pitahaya fruits intended for storage for future seed removal and maintained under the same sowing conditions, the application of higher doses of GA3 was necessary when compared to the previous condition, with a minimum dose of 500 mg/L GA3. The present study shows that the maturation stage of white-fleshed pitahaya fruits intended for seed removal influences the quality of seedlings; therefore, the use of seeds extracted from ripe pitahaya fruits without fermentation is more appropriate for the purpose.


Asunto(s)
Germinación , Plantones , Frutas , Germinación/fisiología , Giberelinas , Fitomejoramiento , Semillas
3.
Rev Neurol ; 69(9): 370-376, 2019 Nov 01.
Artículo en Español, Inglés | MEDLINE | ID: mdl-31657449

RESUMEN

INTRODUCTION: The concrete burden of neonatal seizures in neurodevelopmental outcome of term newborns is still unknown in literature. The aim of this study was to describe prognostic predictors in neonatal seizures. SUBJECTS AND METHODS: Observational prospective study of term neonates with clinical seizures from a tertiary center (2009-2018). Adverse outcome was determined as death, global developmental delay, cerebral palsy or epilepsy. Perinatal characteristics, etiology, electrographic features, neuroimaging and antiepileptic treatment were analyzed in a logistic regression model. RESULTS: A total of 102 newborns were included (52 infants with normal outcome). Twelve fatalities were registered. In the survival group, 38 children had an adverse outcome (28 global developmental delay, 27 cerebral palsy, 21 epilepsy). From the prognostic variables identified in univariate analysis, perinatal complications, seizure onset in the first day of life, moderate to severe abnormal background activity, abnormal amplitude-integrated EEG pattern, and treatment response remained independently associated with adverse outcome after a logistic regression model. CONCLUSIONS: There is conflicting data about surrogate markers in neonatal seizures. Aside from confirming the predictive value of previously described variables, we observed that amplitude-integrated EEG monitoring is a forthcoming prognostic tool. Future approaches may include a wider use of amplitude-integrated EEG monitoring, being crucial for timely seizure identification and prompt treatment.


TITLE: Predictores pronósticos de desarrollo neurológico en recién nacidos a término con crisis neonatales.Introducción. El peso específico de las crisis neonatales en el pronóstico neurológico de recién nacidos a término no se conoce bien, por lo que el objetivo del estudio era describir predictores pronósticos en crisis neonatales. Sujetos y métodos. Estudio observacional prospectivo de recién nacidos a término con crisis clínicas en un centro terciario (2009-2018). Pronóstico adverso se definió como muerte, retraso global del desarrollo, parálisis cerebral o epilepsia. Se analizaron las características perinatales, la etiología, los hallazgos electroencefalográficos, la neuroimagen y los tratamientos antiepilépticos siguiendo un modelo de regresión logística. Resultados. Se incluyó a un total de 102 recién nacidos (52 de los cuales tenían desarrollo normal). Se registraron 12 fallecimientos. En el grupo de supervivientes, 38 niños tuvieron un pronóstico desfavorable (28 con retraso global del desarrollo, 27 con parálisis cerebral, 21 con epilepsia). De las variables pronósticas identificadas en el análisis univariante, las complicaciones perinatales, el inicio de las crisis en el primer día de vida, la actividad basal anormal moderada a grave, un patrón anormal en el electroencefalograma de amplitud integrada y la respuesta al tratamiento continuaron mostrándose como independientemente asociadas a pronóstico adverso después de aplicar un modelo de regresión logística. Conclusiones. Existen datos contradictorios sobre marcadores subrogados en crisis neonatales. Aparte de confirmar el valor predictivo de variables previamente descritas, se halló que la monitorización con electroencefalograma de amplitud integrada constituye una prometedora herramienta diagnóstica. En el futuro, se debería extender su utilización en el abordaje de estos pacientes, lo que sería de vital importancia para un diagnóstico y un tratamiento precoces.


Asunto(s)
Parálisis Cerebral/etiología , Discapacidades del Desarrollo/etiología , Epilepsia/etiología , Convulsiones/complicaciones , Parálisis Cerebral/epidemiología , Preescolar , Discapacidades del Desarrollo/epidemiología , Epilepsia/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Pronóstico , Estudios Prospectivos
4.
Int Endod J ; 51(11): 1292-1300, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29682752

RESUMEN

AIM: To test the hypothesis that polyacrylic acid-based and calcium silicate materials are able to increase mineral density of artificially demineralized dentine produced by a microcosm model for caries formation. METHODOLOGY: Forty-five dentine cavities were prepared in nine sound human third molars (five in each tooth). Specimens received a bacterial inoculum and were incubated in BHI plus 5% of sucrose for 96 h to allow biofilm formation. After that, the specimens were scanned in a high energy micro-CT (baseline stack) and then, each cavity was filled with different cements: zinc polycarboxylate (Poly Zinc™, Prevest DenPro, Jammu, India), conventional glass-ionomer (Ketac Molar, 3M ESPE, Seefeld, Germany) and two calcium silicate-based materials (MTA, Angelus, Londrina, Brazil and Biodentine™, Septodont, Saint Maur des Fosses, France) whilst the central cavity was filled with utility wax (negative control). Specimens were kept for 45 days under simulated intrapulpal pressure using simulated body fluid and after, they were again scanned (treated stacks). Reconstruction of the acquired projections was accomplished using standardized parameters, and the percentage mineral density change was calculated around each cavity. Data were tested for normality using the Shapiro-Wilk test, followed by nonparametric methods. RESULTS: A microcosm artificial caries model was able to cause dentine demineralization (±90% related to sound dentine). Significant increases in dentine mineral density were achieved using MTA or Poly Zinc™ (43.56% and 41.64% remineralization), followed by Biodentine™ (36.40%) and Ketac Molar (32.54%), P < 0.05. CONCLUSION: All cements increased mineral density in demineralized dentine, but zinc polycarboxylate cement and MTA had greater bioactive potential. Micro-CT proved to be an effective method to evaluate changes in mineral density within dentine in contact with bioactive materials.


Asunto(s)
Resinas Acrílicas/farmacología , Compuestos de Calcio/farmacología , Caries Dental/tratamiento farmacológico , Caries Dental/metabolismo , Cementos Dentales/farmacología , Minerales/química , Silicatos/farmacología , Adolescente , Biopelículas/crecimiento & desarrollo , Niño , Caries Dental/diagnóstico por imagen , Caries Dental/microbiología , Dentina , Cementos de Ionómero Vítreo , Humanos , Ensayo de Materiales , Tercer Molar/efectos de los fármacos , Cemento de Policarboxilato , Desmineralización Dental
5.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 222-230, Jan.-Feb. 2018. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-888083

RESUMEN

Foram avaliados os efeitos tóxicos do hormônio 17β-estradiol (E2) livre e complexado à β-ciclodextrina (CD) sobre o comportamento e a fisiologia de tilápia (Oreochromis niloticus). Os peixes foram observados por 30 dias, em dois estágios do desenvolvimento (alevino e juvenil), pelo método ad libitum, para a confecção de um etograma. Posteriormente, juvenis foram divididos em três grupos: controle e expostos ao E2 (10ng/L) livre e complexado à β-ciclodextrina (β-CD:E2) por 90 dias. Foram avaliados o comportamento pelo método de varredura instantânea, o consumo de ração, o ganho de peso e a mortalidade em diferentes intervalos. Os alevinos e os juvenis apresentaram frequências de exibição comportamentais diferentes (P<0,05) nos eventos: Afastar (4,7±1,3 e 3,6±0,6%) e Ondulação de repulsão (2,3±0,9 e 1,3±1,0%). Os juvenis expostos ao complexo β-CD:E2 apresentaram aumento (P<0,05) na exibição dos comportamentos agressivos, como Afastar, Ataque caudal, Confronto prolongado, Perseguição, Fuga, e menor mortalidade, quando comparados ao grupo exposto ao E2 livre e controle. Pode-se concluir que a complexação do E2 com a β-CD alterou a toxicidade do E2, pois promoveu um aumento na frequência de exibição dos comportamentos agressivos e interferiu na mortalidade dos animais.(AU)


Toxic effects of free and complexed 17β-estradiol (E2) hormone into β-cyclodextrin (CD) on the behavior and physiology of tilapia (Oreochromis niloticus) were evaluated. The fish were observed for 30 days in two stages of development (fingerling and juvenile) by the ad libitum method to make an ethogram. After this, juveniles were divided into three groups: control and exposed to free E2 (10ng/L) and complexed into β-cyclodextrin (β-CD:E2) for 90 days. The behavior was evaluated through scan sampling method, feed intake, body mass and mortality at different intervals. The fingerlings and juveniles showed behavioral patterns with different display frequencies (P<0.05) for events: Move Away (4.7±1.3 and 3.6±0.6%) and Waving Repulsion (2.3±0.9 and 1.3±1.0%). The juveniles exposed to β-CD:E2 complex showed a significant increase (P<0.05) in the frequency of display of aggressive behaviors as Move Away, Caudal Attack, Clash Extended, Chase, Escape and decrease of mortality when compared to group exposed to free E2 and control. In conclusion, complexation of E2 into β-CD modified E2 toxicity, because it promoted an increase in the frequency of display of aggressive behaviors and it affected the mortality of animals.(AU)


Asunto(s)
Animales , Cíclidos/metabolismo , beta-Ciclodextrinas/análisis , Estradiol/análisis
6.
Arq. bras. med. vet. zootec ; 68(2): 387-396, mar.-abr. 2016. tab, graf
Artículo en Portugués | LILACS | ID: lil-779781

RESUMEN

Os hormônios esteroides presentes em várias gerações de contraceptivos orais combinados (COC) podem se apresentar como disruptores endócrinos, produzindo alterações no comportamento e na fisiologia de peixes. Diante disso, o objetivo deste trabalho foi avaliar os efeitos de hormônios esteroides presentes em COC sobre os parâmetros comportamentais de Betta splendens, um peixe ornamental usado na aquariofilia e bastante agressivo. Machos adultos foram observados pelo método ad libitum para confecção do etograma e divididos em cinco grupos, controle e expostos aos hormônios: 17β-estradiol (E2); levonorgestrel e etinilestradiol (LEA - segunda geração de COC); gestodeno e etinilestradiol (GEA - terceira geração de COC); e drospirenona e etinilestradiol (DEA - quarta geração de COC). Os peixes foram expostos por 30 dias à concentração final de 10ng/L. Foram avaliados os comportamentos pelos métodos de varredura instantânea e animal-focal, bem como o consumo de ração. No método varredura, o comportamento descansar apresentou o maior valor (54,4±10,1%) no grupo E2 (P<0,05). Os comportamentos agressivos de carga (16,1±3,6%) e recuar e carga (16,4±5,1%) apresentaram os maiores valores no grupo controle em relação aos demais grupos (P<0,05). Os animais do grupo E2 apresentaram maior frequência de comportamentos inativos (76,1%) comparados aos de outros grupos. O comportamento atípico natação errática não foi observado no grupo controle, mas foi observado nos grupos experimentais. Os grupos E2, LEA, GEA e DEA apresentaram redução nos comportamentos agressivos (10%) quando comparados ao grupo controle pelo método animal-focal. Não foram observadas diferenças na exibição desses comportamentos ao se compararem os animais expostos às diferentes gerações de contraceptivos e no consumo de ração. Pode-se concluir que 17β-estradiol causou mais efeitos aos peixes e que diferentes gerações de COC apresentaram efeitos tóxicos semelhantes em relação aos comportamentos observados.


The steroid hormones present in many generations of combined oral contraceptives (COC) can act as endocrine disruptors inducing changes in the behavior and physiology of fish. In this context, the aim of this work was to evaluate the effects of steroid hormones present in COC on behavioral parameters of Betta splendes, an aggressive ornamental fish used in the aquariophily. Adult males were observed with the ad libitum method to develop an ethogram and were divided into five groups, Control and exposed to hormones: 17β-estradiol (E2), levonorgestrel and ethinylestradiol (LEA - 2nd COC generation), gestodene and ethinylestradiol (GEA - 3rd COC generation) and drospirenone and ethinylestradiol (DEA - 4th COC Generation). Fish were exposed for 30 days to a final concentration of 10ng/L. The behavior was evaluated by scan sampling and animal-focal methods, and feed intake. In the scan sampling method, the Resting behavior showed the highest value (54.4±10.1%) in E2 group (P<0.05). The aggressive behavior Rush (16.1±3.6%) and Back and Rush (16.4±5.1%) showed the highest values in the control group, compared to the other groups (P<0.05). Animals in the E2 group showed higher frequency of inactive behaviors (76.1%) compared to other groups. Furthermore, the atypical behavior Erratic swimming was not observed in the control group, but it was observed in the experimental groups. The E2, LEA, GEA and DEA groups showed reduction in aggressive behavior (10%) compared to the control group by the animal-focal method. Moreover, no difference was observed in the exhibition of these behaviors and feed intake comparing animals exposed to the different generations of contraceptives. It can be concluded that 17β-estradiol has caused more effects on fish and different generations of COC showed similar toxic effects in the observed behaviors.


Asunto(s)
Animales , Anticonceptivos Orales Combinados/efectos adversos , Hormonas Esteroides Gonadales/administración & dosificación , Peces/fisiología , Conducta Animal/fisiología , Estradiol/efectos adversos , Estradiol/toxicidad , Etinilestradiol/efectos adversos , Etinilestradiol/toxicidad
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