RESUMEN
Abstract This study provides the first contribution of the biology and life table of Aphis forbesi Weed, 1889 (Hemiptera: Aphididae), an important strawberry pest throughout the world. This species lives in the crown and leaf petioles of the plant. It is difficulty to rear this species in laboratory due to protocooperation with ants observed only in the field. We studied the life cycle of A. forbesi on the leaves of the Albion strawberry cultivar at 25 ± 2 °C, 60 ± 10% relative humidity, and a 12-h photophase. The experiment was randomised with 100 replicates. The parameters of the fertility life table were calculated using TabVida. In the population studied, 25% and 46% had four and three instars, respectively. A mean of 1.43 nymphs per female per day was generated. The mean reproductive period was seven days and the mean longevity was 10 days. In every 11 days there is a generation of A. forbesi, where each female has the potential to generate between 6 to 9 individuals daily, increasing its population by 1.2 times. The average life cycle was 16.8 days. High viability observed in all instars and the resulting values of R0, rm and λ suggest that A. forbesi has the capacity to increase their numbers in a short period of time, while generating high populations in strawberry crops, requiring differential management.
Resumo Este trabalho apresenta a primeira contribuição ao estudo de biologia e tabela de vida de fertilidade de Aphis forbesi, Weed, 1889 (Hemiptera: Aphididae), uma importante praga de morangueiro no mundo. Esta espécie se desenvolve na coroa e pecíolo do morangueiro. O desenvolvimento desta espécie em laboratório apresentou dificuldades, possivelmente devido à protocooperação com formigas, observada em campo durante coletas. O ciclo de vida de A. forbesi foi estudado em folhas de morangueiro cultivar ‘Albion’ a 25 ± 2 °C, 60 ± 10% umidade relativa, e fotofase de 12 horas. O experimento foi inteiramente casualizado com 100 repetições. Os parâmetros da tabela de vida de fertilidade foram calculados usando o software TabVida. Na população estudada observou-se que as ninfas apresentaram três e quatro instares, sendo 46 e 25% respectivamente, dos indivíduos que completaram o ciclo de vida. Foi gerada uma média de 1,43 ninfas/ fêmea/ dia. O período reprodutivo médio foi de 7 dias e a longevidade média 10 dias. A cada 11 dias ocorre uma geração de A. forbesi onde cada fêmea tem capacidade de gerar de 6 a 9 indivíduos aumentando em 1,2 vezes a população. O ciclo de vida de A. forbesi durou em média 16,8 dias. A alta viabilidade observada em todos os estádios, e os valores de R0, rm e λ sugerem que A. forbesi tem a capacidade de aumentar seu número em um curto período de tempo, gerando altas populações no cultivo do morangueiro, exigindo manejo diferenciado.
Asunto(s)
Animales , Femenino , Áfidos/crecimiento & desarrollo , Fragaria , Reproducción , Tablas de Vida , Fertilidad , Longevidad , Ninfa/crecimiento & desarrolloRESUMEN
DNA methylation is essential in X chromosome inactivation and genomic imprinting, maintaining repression of XIST in the active X chromosome and monoallelic repression of imprinted genes. Disruption of the DNA methyltransferase genes DNMT1 and DNMT3B in the HCT116 cell line (DKO cells) leads to global DNA hypomethylation and biallelic expression of the imprinted gene IGF2 but does not lead to reactivation of XIST expression, suggesting that XIST repression is due to a more stable epigenetic mark than imprinting. To test this hypothesis, we induced acute hypomethylation in HCT116 cells by 5-aza-2′-deoxycytidine (5-aza-CdR) treatment (HCT116-5-aza-CdR) and compared that to DKO cells, evaluating DNA methylation by microarray and monitoring the expression of XIST and imprinted genes IGF2, H19, and PEG10. Whereas imprinted genes showed biallelic expression in HCT116-5-aza-CdR and DKO cells, the XIST locus was hypomethylated and weakly expressed only under acute hypomethylation conditions, indicating the importance of XIST repression in the active X to cell survival. Given that DNMT3A is the only active DNMT in DKO cells, it may be responsible for ensuring the repression of XIST in those cells. Taken together, our data suggest that XIST repression is more tightly controlled than genomic imprinting and, at least in part, is due to DNMT3A.
Asunto(s)
Humanos , Metilación de ADN/genética , Represión Epigenética/genética , Genoma Humano , Genoma/genética , Impresión Genómica/genética , Factor II del Crecimiento Similar a la Insulina/genética , ARN Largo no Codificante/genética , Azacitidina/administración & dosificación , Azacitidina/análogos & derivados , /genética , Metilación de ADN/efectos de los fármacos , Técnicas de Inactivación de Genes , Genoma Humano/efectos de los fármacos , Hibridación Fluorescente in Situ/métodos , Análisis por Micromatrices , Polimorfismo de Nucleótido Simple , Proteínas/metabolismo , ARN Largo no Codificante/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodosRESUMEN
Um inquérito soroepidemiológico foi realizado em uma amostra de escolares, em 1994, no município de Paracambi, Estado do Rio de Janeiro. Positividade do teste de Inibição da Hemaglutinação foi detectada em 39,2% (145/370) dos escolares pesquisados. A freqüência de positividade foi de 53,8% (78/145) para o sexo feminino e de 46,2% (67/145) para o sexo masculino. A distribuição por faixa etária mostrou uma positividade crescente com o aumento da idade. Cepas do vírus dengue tipo 1 e vírus dengue tipo 2 foram isoladas anteriormente (1990), mostrando a co-circulação de ambos os sorotipos na área. Os índices de infestação predial pelo Aedes aegypti e pelo Aedes albopictus foram determinados.
A seroepidemiological survey was carried out during 1994 in the municipality of Paracambi, state of Rio de Janeiro. Haemagglutination inhibition test positivity was detected in 145 out of 370 (39.2%) schoolchildren. The frequency of positive test by sex was 53.8% (78/145) female and 46.2% (67/145) male. Distribution by age showed the increasing of antibody positivity in older children. Strains of dengue virus type 1 and dengue virus type 2 were isolated before (1990) showing the co-circulation of both serotypes in that area. The house index infestation of Aedes albopictus and Aedes aegypti has been determined.
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Adolescente , Animales , Niño , Preescolar , Femenino , Humanos , Masculino , Dengue/epidemiología , Aedes , Distribución por Edad , Anticuerpos Antivirales/sangre , Brasil/epidemiología , Dengue/inmunología , Dengue/transmisión , Insectos Vectores , Prevalencia , Estudios Seroepidemiológicos , Distribución por Sexo , Virus del Dengue/inmunologíaRESUMEN
A retrospective serologic study was carried out in Fortaleza, State of Ceará, Brazil, in order to detect the dengue virus activity before recognizing the epidemic of 1994. Mac-Elisa was performed by using a mixture of specific DEN-1 and DEN-2 antigens on serum samples from the Emilio Ribas Laboratory collection. Samples were obtained from 1,224 patients with exanthematic febrile disease and negative serological results for rubella. All specimens were taken during November 1993 to May 1994. The results confirmed dengue infections in Fortaleza by November 1993, approximately six months before the beginning of the epidemic, proving how misleading diagnosis of dengue infection are still troublesome, in spite of the strong dengue activity in Ceará. The authors stress the urgent necessity to implement the active surveillance system in order to prevent another extensive fever epidemics in the state. Epidemiological background of the dengue activity in the State of Ceará is also described.
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Humanos , Dengue , Brasil , Estudios RetrospectivosRESUMEN
Post-Traumatic Intraventricular Haemorrhage (IVH) occurs after a traumatic head injury and is usually associated with an adjacent intracerebral hemorrhage or brain contusion. Post-traumatic IVH was associated with other brain lesion in most cases. In fact, thepethogenetic mechanism that governs the formation of a post-traumatic IVH is not clear. Computed tomography represents the first reliable and nonsurgical tool for identifying IVH, where the sites of ventricular haemorrhage have been analysed. Ventricular drainage is used to made a good recovery in pacients with IVH. Prognostic in traumatic IVH, in general, is poor. In our study, we had 19 pacients with IVH, with 76 per cent male and 24 per cent female. Age average's were 30,3. As for the causes we had hit by a car, car collision, gunshot accident, fall and fight. CT was very important to detect IVH in our cases. The surgery was more frequent in our study when additional intracranial lesions were present. There were 8 death and 11 pacients had good recovery