Diazepam reverses the alveolar bone loss and hippocampal interleukin-1beta and interleukin-6 enhanced by conditioned fear stress in ligature-induced periodontal disease in rats.

BACKGROUND AND OBJECTIVE: Stress and anxiety have been associated with chronic periodontitis, but few studies examining the effects of psychotropic drugs on periodontal health have been performed. Therefore, we aimed to investigate the effects of diazepam on the progression of periodontitis in chronically stressed rats. MATERIAL AND METHODS: Fourteen Wistar rats were submitted to ligature-induced periodontal disease and were divided into four groups . Two groups were not stressed, whereas two groups were submitted to a conditioned fear stress paradigm for 38 d. Daily diazepam treatment (2 mg/kg, orally) was administered to one unstressed group and to one group submitted to a conditioned fear stress paradigm from day 2 to the day 39, at which point the rats were submitted to an open field test and were killed on day 40. Brains and mandibles were removed for histological and immunohistochemical analyses. RESULTS: Animals exposed to conditioned fear stress presented an increase in freezing behavior, a decrease in locomotor activity, enhanced alveolar bone loss and higher levels of hippocampal interleukin-1beta (IL-1ß) and interleukin-6 (IL-6), compared with the control group. Diazepam, at the dose used in the current study, had no effect on freezing behavior but reversed the decrease in locomotor activity provoked by stress. Additionally, the treatment reduced the levels of hippocampal IL-1ß and IL-6 and alveolar bone loss in Wistar rats. Neither conditioned fear stress nor diazepam treatment had an effect on periodontal IL-1ß or IL-6 levels in animals. CONCLUSION: Our results suggest that diazepam treatment reduces bone loss in rats submitted to conditioned fear stress. In addition, diazepam treatment led to decreased IL-1ß and IL-6 levels in the hippocampus.

Avaliação da região espaçadora 16s-23s dnar como marcador molecular para diferenciação de acidovorax avenae subsp. cattleyae e burkholderia gladioli pv. gladioli patogênicas a orquídeas

ABSTRACT The 16S-23S rDNA spacer region was evaluated as a molecular marker to differentiation of orchids pathogens, Acidovorax avenae subsp. cattleyae and Burkholderia gladioli pv. gladioli. Other species belonging to the two genera such as B. gladioli pv. alliicola, A. avenae subsp. avenae, A. avenae subsp. citrulli, A. anthurii, A. facilis, A. delafieldii and A. konjaci were also analyzed. The PCR amplification of the 16S-23S rDNA spacer region produced a fragment of 1,100 base pairs. The products obtained from all strains were digested with Afa I, Alu I, Hae III and Hpa II and the results showed distinct RFLP patterns for each endonuclease tested. The sequences of 16S-23S rDNA spacer region were aligned and the phylogenetic analysis confirmed the differences between A. avenae subsp. cattleyae e B. gladioli pv. gladioli. The PCR-RFLP technique was very efficient and useful to the identification of these pathogens since they cause very similar symptoms in orchids.

RESUMO A região espaçadora 16S-23S DNAr foi avaliada como marcador molecular para a diferenciação dos patógenos de orquídeas, Acidovorax avenae subsp. cattleyae e Burkholderia gladioli pv. gladioli. Outras espécies pertencentes a esses dois gêneros como B. gladioli pv. alliicola, A. avenae subsp. avenae, A. avenae subsp. citrulli, A. anthurii, A. facilis, A. delafieldii e A. konjaci também foram analisadas. A amplificação por PCR dessa região produziu um fragmento de aproximadamente 1.100 pares de bases para todas as linhagens testadas. Os produtos obtidos foram submetidos a digestões com as enzimas Afa I, Alu I, Hae III e Hpa II e os resultados mostraram perfis distintos de RFLP para A. avenae subsp. cattleyae de B. gladioli pv. gladioli com todas as endonucleases testadas. As seqüências da região espaçadora 16S-23S DNAr foram alinhadas e a análise filogenética confirmou as diferenças entre A. avenae subsp. cattleyae e B. gladioli pv. gladioli. A técnica de PCR-RFLP mostrouse eficiente e muito útil para a identificação desses patógenos, uma vez que eles causam sintomas muito semelhantes em orquídeas.

Adult Citrus Leafminers (Phyllocnistis citrella) Are Not Efficient Vectors for Xanthomonas axonopodis pv. citri.

Interest in the interaction between the citrus leafminer (Phyllocnistis citrella) and citrus bacterial canker, caused by Xanthomonas axonopodis pv. citri, has increased as a greater incidence and severity of canker-diseased plants was observed in groves infested with the citrus leafminer. To determine whether adults of the citrus leafminer could act as vectors of citrus canker, we investigated two potential mechanisms for direct spread by leafminer adults using experimental microcosms. First, adult leafminers were raised on canker-infected foliage and were allowed to mate and lay eggs on healthy plants. These plants then were observed for development of citrus canker symptoms. In a second set of experiments, adults raised on healthy plants were given free access to canker-diseased plants during the period in which they mated and laid eggs on healthy plants. In all, 3,119 mines were produced by developing larvae on a total of 2,384 leaves examined for citrus canker symptoms. No symptoms of citrus bacterial canker disease were observed on any of the healthy test plants in 37 independent experimental trials conducted to test these two potential mechanisms of spread of citrus canker, and the pathogen was not recovered from insects exposed to symptomatic Rangpur lime plants. The upper limit on the rate of transmission was estimated to be less than 0.2% per oviposition event based on the binomial probability distribution. However, when adult P. citrella insects were artificially contaminated with high levels of X. axonopodis pv. citri, transmission to Rangpur lime plants with the induction of citrus canker was observed. This suggests that the ability of P. citrella to transmit X. axonopodis pv. citri is limited by the rate at which it can acquire inoculum from infected plants. The results support the conclusion that adult citrus leafminers are not efficient vectors for citrus canker bacteria, and the disease is unlikely to be spread this way.

[Giant left atrial myxoma]. / Mixoma gigante de átrio esquerdo.

A 65 year-old man with dilated cardiomyopathy and long history of high blood pressure and a previous cerebral vascular accident had a giant left atrial myxoma as an echocardiographic finding.

Piloroplastia. / Piloroplasty

Os autores fazem em ordem cronologica, exaustiva revisao da literatura das diferentes tecnicas de piloroplastia, desde a primeira descrita por Heineke e Mikulicz em 1886 e 1888. Definem piloroplastia como todo procedimento cirurgico sobre o piloro, englobando a pilorectomia e a piloromiotomia. Apresentaram ao todo 35 tecnicas operatorias