The genetic diversity of Plasmodium malariae and Plasmodium brasilianum from human, simian and mosquito hosts in Brazil

Plasmodium malariae is a protozoan parasite that causes malaria in humans and is genetically indistinguishable from Plasmodium brasilianum, a parasite infecting New World monkeys in Central and South America. P. malariae has a wide and patchy global distribution in tropical and subtropical regions, being found in South America, Asia, and Africa. However, little is known regarding the genetics of these parasites and the similarity between them could be because until now there are only a very few genomic sequences available from simian Plasmodium species. This study presents the first molecular epidemiological data for P. malariae and P. brasilianum from Brazil obtained from different hosts and uses them to explore the genetic diversity in relation to geographical origin and hosts. By using microsatellite genotyping, we discovered that of the 14 human samples obtained from areas of the Atlantic forest, 5 different multilocus genotypes were recorded, while in a sample from an infected mosquito from the same region a different haplotype was found. We also analyzed the longitudinal change of circulating plasmodial genetic profile in two untreated non-symptomatic patients during a 12-months interval. The circulating genotypes in the two samples from the same patient presented nearly identical multilocus haplotypes (differing by a single locus). The more frequent haplotype persisted for almost 3 years in the human population. The allele Pm09-299 described previously as a genetic marker for South American P. malariae was not found in our samples. Of the 3 non-human primate samples from the Amazon Region, 3 different multilocus genotypes were recorded indicating a greater diversity among isolates of P. brasilianum compared to P. malariae and thus, P. malariae might in fact derive from P. brasilianum as has been proposed in recent studies. Taken together, our data show that based on the microsatellite data there is a relatively restricted polymorphism of P. malariae parasites as opposed to other geographic locations.

Periodontal conditions and treatment needs (CPITN) in a worker population in Araraquara, SP, Brazil

This research was carried out to assess the periodontal conditions and treatment needs in a worker population at Sugar and Alcohol Refineries in Araraquara, SP, Brazil. A sample of 528 workers aged 18-64 years was examined by one examiner, previously trained, using the CPITN. The results showed that calculus was the most frequently observed periodontal condition in the age groups 18-19, 20-24, 25-29 and 30-34. In the age groups 35-44 and 45-64, the periodontal condition most frequently observed was shallow pockets. The analysis of the results showed that treating all conditions in all persons would demand an amount of care that could not be provided by any dental service. Therefore, the priority should be based on population strategy and primary prevention programmes to benefit the periodontal health of the majority of people.

[DMF index simplification in people aged 18 to 25 years]

The DMF index can be estimated at double the value observed in the exam of two hemiarchs (Upper Right and Lower Left), or at four times the value obtained from six teeth (First Molar and Central Incisor Upper Right, first bicuspid upper left, second molar and lateral incisor lower left and second bicuspid lower right. The estimates were made by the use of methods of descriptive statistics, averages, percentages and the coefficient of the prevalence of caries, in a sample of 100 people, aged from 18 to 25 years.

[Simplified oral hygiene index for ages 4 to 6 and 7 to 10 (deciduous and mixed dentition)]

The purpose of this research is to obtain simplified index to evaluate oral hygiene in children. They are divided in two groups: 1) 4-6 years and; 2) 7-10 years. The criteria described by GREEN & VERMILLION, 1960 and 1964 were selected. Calculus was excluded. Once obtained the total data, a simplified of the total index was performed. For the ages 4 to 6 years, we selected labial surfaces of the 54, 61, 82 and the lingual surface of 75. For the mixed dentition we added the labial surface of 26 and the lingual surface of 46. In both dentition, simplified index showed significant correlation with the total index.

[Simplified caries index for ages 4 to 6 and 7 to 10 (deciduous and mixed dentition)]

The purpose of this research is to obtain a simplified caries index. Four hundred and twenty children, both sexes, 4 to 10 years of age were divided in two groups: 4-6 years and 7-10 years. For caries prevalence, on the deciduous dentition, we used a modified GR JEBBEL index and for permanente teeth, the criteria established by KLEIN et alii, 1938. Considering the cumulative effects of caries, in the mixed dentition, we considered the sum of dmfs and DMFS. A simplification of the total index was performed, for the ages 4 to 6 years considering the teeth 54, 61, 75, 82 and for mixed dentition we added the tooth 26 and 26. The results showed in both dentition, that simplified caries index showed significant correlation with the total index.

[Simplified gingival index for ages 4 to 6 and 7 to 10. (Deciduous and mixed dentition)]

The main purpose of this research is to obtain an simplified gingival index. Four hundred and twenty children, both sexes 4 to 10 years of age were selected. They are divided in two groups: 4-6 years and 7-10 years. For gingival index, the criteria based on SCHOUR & MASSLER, 1947, were used. To obtain the total data of the studied conditions, a simplification of the total index was performed. For the ages 4 to 6 years, we selected labial surfaces of the 54, 61, 75, 82. For the ages 7 to 10 years, we added the labial surfaces of 26 and 46. The means for the total and simplified index were obtained for each age group sex. The data were analysed by Pearson's correlation coefficient and linear regression. In both dentitions, the simplified index showed significant correlation with the total index.