Relationship between digestive enzymes and food habit of Lutzomyia longipalpis (Diptera: Psychodidae) larvae: Characterization of carbohydrases and digestion of microorganisms.

The sandfly Lutzomyia longipalpis (Lutz and Neiva, 1912) is the main vector of American Visceral Leishmaniasis. In spite of its medical importance and several studies concerning adult digestive physiology, biochemistry and molecular biology, very few studies have been carried out to elucidate the digestion in sandfly larvae. Even the breeding sites and food sources of these animals in the field are largely uncharacterized. In this paper, we describe and characterize several carbohydrases from the gut of L. longipalpis larvae, and show that they are probably not acquired from food. The enzyme profile of this insect is consistent with the digestion of fungal and bacterial cells, which were proved to be ingested by larvae under laboratory conditions. In this respect, sandfly larvae might have a detritivore habit in nature, being able to exploit microorganisms usually encountered in the detritus as a food source.

Analysis of three dental fluorosis indexes used in epidemiologic trials.

The objective of this paper was to compare the DEAN, T-F and TSIF dental fluorosis indexes in relation to prevalence of surfaces, teeth and locality, and to verify the statistical correlation among them. The sample consisted of 461 schoolchildren, ages 12-14 years, born and reared in 3 cities in the State of São Paulo from 2 years of age. A total of 153 were from Cesário Lange with a fluoride concentration in the water supply of 1.4 ppm F, 142 from Piracicaba (0.7 ppm F) and 166 from Iracemápolis (< 0.3 ppm F). The clinical examination was conducted after tooth brushing, using a plane mirror, artificial light and air drying of the teeth for 1 min. Premolars, second molars, and occlusal surfaces were the most severely affected. The three indexes showed similar percentages of children affected in the 3 three cities: 32.7%, 16.9% and 4.2% for the DEAN index, 33.3%, 17.6% and 4.2% for the T-F index and 32.7%, 16.9% and 4.2% for the TSIF index. There were no difficulties in using the three indexes in the field trials; thus the use of any one may be recommended in regions with similar fluoride concentrations to those of this study.

[Evaluation of the prevalence of dental caries in school-children from an urban area of Southeastern Brazil]. / Avaliação da prevalência de cárie dentária em escolares de localidade urbana da região Sudeste do Brasil.

An epidemiologic survey of dental caries was undertaken in the town of Paulínia. S. Paulo state, south-eastern Brazil, in 1994, for the purpose of comparing the present prevalence with that registered during the previous study of 1980. The children examined numbered 1,416, were of both sexes and aged 7-14. Ten dentists, preciously trained, used DMF.T and DMF.S dental caries indexes. A level of prevalence of dental caries 67.8% below that of 1980 was found. Further, there had been an inversion of DMF.T index components. Whereas in 1980 the component caries was higher (69.5%), while the filing component prevailed (79.0%) in 1994. The missing tooth component has disappeared altogether in this recent survey.

Prevalence of dental caries in permanent teeth of white and black schoolchildren in Brazil.

The authors studied the prevalence of dental caries in white and black schoolchildren of Piracicaba, State of São Paulo, Brazil. The Student t-test, applied to the coefficient of prevalence of caries, revealed means significantly greater at the 5% level in whites than in blacks in the following groups: 7 years, both sexes; 8 years, both sexes; 9 years, males; 10 years, both sexes; 11 years, males.