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Despite considerable progress on the study of the effect of standardized extract of Gingko biloba (EGb) on memory processes, our understanding of its role in the persistence of long-term memory (LTM) and the molecular mechanism underlying its effect, particularly episodic-like memory, is limited. We here investigated the effects of EGb on the long-term retention of recognition memory and its persistence and BDNF expression levels in the dorsal hippocampal formation (DHF). Adult male Wistar rats (n = 10/group) were handled for 10 min/5 day. On day 6, the animals were treated with vehicle or 0.4 mg/kg diazepam (control groups) or with EGb (250, 500 or 100 mg/kg) 30 min before the training session (TR1), in which the animals were exposed to two sample objects. On day 7, all rats underwent a second training session (TR2) as described in the TR1 but without drug treatment. Object recognition memory (ORM) was evaluated on day 8 (retention test, T1) and day 9 (persistence test, T2). At the end of T1or T2, animals were decapitated, and DHF samples were frozen at -80 °C for analyses of the differential expression of BDNF by Western blotting. EGb-treated groups spent more time exploring the novel object in T2 and showed the highest recognition index (RI) values during the T1 and T2, which was associated with upregulation of BDNF expression in the DHF in a dose-and session-dependent manner. Our data reveal, for the first time, that EGb treatment before acquisition of ORM promotes persistence of LTM by BDNF differential expression.

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OBJECTIVE: To assess risk factors for gastroesophageal reflux disease (GERD) in very low birth weight infants with bronchopulmonary dysplasia. METHODS: A case-control study was carried out in 23 cases and 23 control subjects with bronchopulmonary dysplasia submitted to 24-hour esophageal pH monitoring between January 2001 and October 2005. Cases and controls were compared for gestational age, birth weight, gender, use of antenatal steroids, duration of assisted ventilation, duration of oxygen therapy, length of gastric tube use, administration of xanthines, postconceptual age, and weight at esophageal pH monitoring. Multiple logistic regression analysis was used to establish the odds ratio (OR) with a 95% confidence interval (95%CI). RESULTS: None of the groups (with and without GERD) showed statistically significant differences in terms of demographic variables and postnatal outcome, use of antenatal and postnatal corticosteroids, or in terms of caffeine use and duration of mechanical ventilation and oxygen therapy. However, feeding intolerance (OR = 6.55; 95%CI 1.05-40.8) and length of gastric tube use (OR = 1.67; 95%CI 1.11-2.51) turned out to be risk factors for GERD. Postconceptual age at the time of pH monitoring (OR = 0.02; 95%CI < 0.001-0.38) was regarded as a protective factor against GERD. CONCLUSION: The data obtained allow inferring that prolonged gastric tube use and feeding intolerance increase the risk for GERD. On the other hand, older postconceptual age at the time of pH monitoring reduces the risk for GERD in preterm infants with bronchopulmonary dysplasia weighing less than 1,500 g.

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OBJETIVO: Conhecer os fatores de risco para a doença por refluxo gastroesofágico (DRGE) em recém-nascidos de muito baixo peso com displasia broncopulmonar. MÉTODOS: Realizou-se um estudo caso-controle incluindo 23 casos e 23 controles com displasia broncopulmonar, sendo realizada investigação por monitorização prolongada do pH esofágico no período de janeiro de 2001 a outubro de 2005. Para cada caso, selecionou-se um controle, e foram comparados pela idade gestacional, peso ao nascimento, gênero, uso de corticóide pré-natal, tempo de ventilação assistida, tempo de oxigenoterapia, tempo de uso de sonda gástrica, uso de xantinas, idade pós-conceptual e peso durante a monitorização do pH esofágico. Realizou-se a análise por regressão logística múltipla para estabelecer o odds ratio (OR) com intervalo de confiança de 95 por cento (IC95 por cento). RESULTADOS: Os dois grupos (com e sem DRGE) não apresentaram diferenças significativas em relação às variáveis demográficas e de evolução pós-natal, uso de corticóide pré e pós-natal, bem como ao tempo de uso de cafeína, ventilação mecânica e oxigenoterapia. Entretanto, as variáveis intolerância alimentar (OR = 6,55; IC95 por cento 1,05-40,8) e tempo de uso de sonda gástrica (OR = 1,67; IC95 por cento 1,11-2,51) comportaram-se como fatores de risco para DRGE. A variável idade pós-conceptual ao exame de monitorização do pH (OR = 0,02; IC95 por cento < 0,001-0,38) comportou-se como fator protetor para DRGE. CONCLUSÃO: Os dados obtidos permitem inferir que o tempo prolongado de uso de sonda gástrica e a intolerância alimentar aumentam a probabilidade para DRGE. Já a maior idade pós-conceptual ao exame diminui a chance para DRGE em prematuros com menos de 1.500 g com displasia broncopulmonar.

OBJECTIVE: To assess risk factors for gastroesophageal reflux disease (GERD) in very low birth weight infants with bronchopulmonary dysplasia. METHODS: A case-control study was carried out in 23 cases and 23 control subjects with bronchopulmonary dysplasia submitted to 24-hour esophageal pH monitoring between January 2001 and October 2005. Cases and controls were compared for gestational age, birth weight, gender, use of antenatal steroids, duration of assisted ventilation, duration of oxygen therapy, length of gastric tube use, administration of xanthines, postconceptual age, and weight at esophageal pH monitoring. Multiple logistic regression analysis was used to establish the odds ratio(OR) with a 95 percent confidence interval (95 percentCI). RESULTS: None of the groups (with and without GERD) showed statistically significant differences in terms of demographic variables and postnatal outcome, use of antenatal and postnatal corticosteroids, or in terms of caffeine use and duration of mechanical ventilation and oxygen therapy. However, feeding intolerance (OR = 6.55; 95 percentCI 1.05-40.8) and length of gastric tube use (OR = 1.67; 95 percentCI 1.11-2.51) turned out to be risk factors for GERD. Postconceptual age at the time of pH monitoring (OR = 0.02; 95 percentCI < 0.001-0.38) was regarded as a protective factor against GERD. CONCLUSION: The data obtained allow inferring that prolonged gastric tube use and feeding intolerance increase the risk for GERD. On the other hand, older postconceptual age at the time of pH monitoring reduces the risk for GERD in preterm infants with bronchopulmonary dysplasia weighing less than 1,500 g.

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