ABSTRACT: The objective of this study was to determine the effect of the subgingival irrigation of chlorhexidine 0.12 % of the total anaerobic microbiota. Microbial sampling to 30 subjects with periodontitis stage II Grade B, in pockets with a periodontal probing depth > 4 mm. The subgingival irrigation was made with 5 mL of chlorhexidine in the test group and with 5 mL of distilled water in the control group. 24 hours after the procedure was obtained a second sample to compare. It was found that the subgingival irrigation with chlorhexidine at 0.12 % achieved a statistically significant decrease in anaerobic microbiota (p< 0.05).

RESUMEN: El objetivo del presente estudio fue determinar el efecto de la irrigación subgingival de la clorhexidina 0,12 % sobre la microbiota anaeróbica total. Se tomaron muestras microbiológicas a 30 sujetos con periodontitis estadio II grado B, en sacos periodontales con una profundidad de sondaje > 4 mm. Se realizó la irrigación subgingival con 5 mL. de clorhexidina en el grupo test y con 5 mL. de agua destilada en el grupo control. 24 horas después del procedimiento se obtuvo una segunda muestra a comparar. Se detectó que la irrigación subgingival con clorhexidina al 0,12 % logra disminuir en forma estadísticamente significativa la microbiota anaeróbica total (p< 0,05).

The anti-Trypanosoma cruzi activity of natural products isolated from Azorella compacta was evaluated, with particular emphasis on their effect against intracellular amastigotes. Five diterpenoids from A. compacta derived from mulinane and azorellane were isolated and identified. Only two products, named azorellanol (Y-2) and mulin-11,3-dien-20-oic acid (Y-5), showed trypanocidal activity against all stages of T. cruzi including intracellular amastigotes. At 10 µM, these compounds displayed a strong lytic activity. It ranged from 88.4 ± 0.6 to 99.0 ± 1 % for all strains and stages evaluate, with an IC50 /18 h values of 20-84 µM and 41-87 µM, respectively. The development of intracellular amastigotes was also inhibited by nearly 60% at 25 µM. The trypanocidal molecules Y-2 and Y-5 did show different degrees of cytotoxicity depending on the cell line tested, with an IC50 /24 h ranging from 33.2 to 161.2 µM. We evaluated the effect of diterpenoids against intracellular T. cruzi forms by immunofluorescent identification of a specific membrane molecular marker (Ssp-4 antigen) of the T. cruzi amastigote forms. The accuracy and reproducibility of the measurements were found to be outstanding when examined by confocal microscopy.

The effect of El Niño/ENSO on terrestrial atmosphere appears to be extremelly clear. However there are outstanding evidences showing its effect on humans and their activities. In fact, prevalence of some parasitic infections have increased during El Niño phenomenon. The reasons for that are the migrations of sylvatic mammals, fishes and birds as well as by environmental contamination. In this report, we show evidence respect of new cases of human infection by Diphyllobothrium pacificum clearly associated with a cyclic manifestation of El Niño in the Chilean Pacific coast during 1975-2000