Ocorrência de enteroparasitos em centros de educação infantil no Município de Patos de Minas, MG, Brasil

Considering the high prevalence of the parasitic diseases in Brazil and its close relationship with the socio-economic and cultural levels of the population, aimed to establish the occurrence of enteroparasites in children of six Centers of Education Child (CEIs) of the municipality of Patos of Minas (MG). Were collected three samples of faeces of 161 children from zero to six years of age. Were used the Lutz and Baermann-Moraes' methods, to the detection of cysts of protozoa, eggs and larvae of helminths. Coproparasitological analyses showed positivity of 73%. The most frequent helminths were: Ascaris lumbricoides (50%), hookworm (22%) and Enterobius vermicularis (0.6%). Among the protozoa highlighted were: Entamoeba histolytica/E. dispar (22%) and Giardia lamblia (32%). The high occurrence of enteroparasites evidenced the need for an effective health policy in the CEIs of the municipality of Patos of Minas to the fight against intestinal parasites.

Detection and localization of small nuclear ribonucleoproteins (snRNPs) in trypanosomatids using anti-m(3)G antibodies

This work reports for the first time the identification and immunolocalization, by confocal and conventional indirect immunofluorescence, of m(3)G epitopes present in ribonucleoproteins of the following trypanosomatids: Trypanosoma cruzi epimastigotes of three different strains, Blastocrithidia ssp., and Leishmania major promastigotes. The identity of these epitopes and hence the specificity of the anti-m(3)G monoclonal antibody were ascertained through competition reaction with 7-methylguanosine that blocks the Ig binding sites, abolishing the fluorescence in all the parasites tested and showing a specific perinuclear localization of the snRNPs, which suggests their nuclear reimport in the parasites. Using an immunoprecipitation technique, it was also possible to confirm the presence of the trimethylguanosine epitopes in trypanosomatids.

Molecular detection of Hepatozoon spp. in Brazilian and exotic wild carnivores

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Occurrence of antibodies anti-Neospora caninum, anti-Toxoplasma gondii, and anti-Leishmania chagasi in serum of dogs from Para State, Amazon, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Validation of a Leishmania infantum ELISA rapid test for serological diagnosis of Leishmania chagasi in dogs

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Proteins of Leishmania (Viannia) shawi confer protection associated with Th1 immune response and memory generation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Spliceosomal Proteomics in Trypanosoma brucei Reveal New RNA Splicing Factors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Infection by Austrodiplostomum compactum metacercariae in fish from the Nova Avanhandava reservoir, Tiete river, São Paulo State, Brazil.

This study aimed to evaluate the infection by the Austrodiplostomum compactum metacercariae in fishes from the Nova Avanhandava Reservoir, low Tiete river, São Paulo State, Brazil. The parasites were collected from eye (aqueous and vitreous humor), fixed in AFA solution and stained with carmine. The morphometric analysis was performed using a computerized system for analysis of images QWin Lite 2.5 (Leica). Prevalence, mean intensity of infection and abundance of infected fish were calculated. of the 22 species of fish registered, five were infected by metacercariae: Hoplias malabaricus, Metynnis maculatus, Plagioscion squamosissimus, Satanoperca pappaterra and Schizodon imparts. of the 627 fish evaluated, 34% were infected. A higher prevalence was observed in P. sqnamosissionis and S. pappaterra. Schizodon nasutus and M. maculatus are new hosts reported for A. compactum metacercariae.

Quantitative aspects of the migration and evolutive asynchronism of Schistosoma mansoni in mice

Two groups of white mice (Mus musculus) were infected with 65 and 440 cercariae transcutaneously. Migration of Schistosoma mansoni from skin to the lungs and to the portal system thereafter was studied through fitting mathematical equations. Six evolutive stages previously defined were used to determine the asynchronic development of parasites in the portal system. Equations the moment of maximum schistosomula recovery in skin and lungs. In the portal system the equations lead to different days of maximum recovery according to each stage. These differences measure quantitatively the asynchronism of S. mansoni.

Parasitoses em lactentes de 0-12 meses atendidos na Faculdade de Medicina de Botucatu - São Paulo

Infestation by protozoa and/or helminths is considered to be extremely rare in infants. We therefore reviewed the records of all infants up to 12 mth of age attending the Paediatric Department from January 1973 to June 1977, in order to assess the frequency of stool examinations for parasites within this age group, the percentage of positive results in these examinations, and some personal characteristics which propitiated parasitic infestation. Some characteristics of the investigated infants were compared to those of a representative sample of the total number of infants attending during the same period. Stool examinations were realized in 11.8% of the 1,162 attending patients and of those, 15.3% were positive. The proportion of positive cases became 24.0% when the infants in whom there was a history of parasites being passed were included. Ascaris lumbricoides and Giardia lamblia were the parasites most frequently found, respectively in 42.8% and 37.1% of the positive cases. The only detected difference between the control group and the group of infants who had parasitologic examinations was the presence of diarrhea, significantly more frequent in the investigated group. The proportion of positive cases was significantly greater in girls, in infants older than 6 mth and when diarrhea was present for up to 15 days, than in boys, in infants up to 6 mth of age and in chronic diarrhea, respectively. Our results show that parasites were investigated in only a small percentage of infants under 1 yr of age, but that in this age group already, parasitic infestation does occur with a certain frequency. As investigated cases were selected, mainly due to the presence of diarrhea, the real prevalence of parasitism in infants under 1 yr of age was impossible to evaluate.

Prova de absorção de gordura em crianças.

To overcome the difficulties observed with fecal fat estimations, we studied fat absorption in 4 m to 12 years old children, assessing increments of serum triglycerides after administration of corn oil. Eighteen well-nourished children without gastrointestinal symptoms or parasites, 31 children with protein-calorie malnutrition (PCM), with or without protracted diarrhea and/or intestinal parasites and nine children with specific malabsorptive entities were studied. Serum triglycerides (TG) were measured before, 2 and 4 hours after the administration of 2 g/kg of corn oil per os. For control infants below 2 years no significant differences between the fasting level and those after 2 and 4 hours were observed. For children above this age significant absorption occurred by 2 hours but more intensively after 4 hours, an increment of TG above 35 mg% being considered normal. A good discrimination between TG increments of controls and malabsorptive children over 2 years was observed. In conclusion, the oral fat loading test, is applicable for children over 2 year of age. For infants below this age other schedules should be tested.

Western blot analysis of tick antigens from a Rhipicephalus sanguineus unfed larval extract and identification of antigenic sites in tick sections using immunohistochemistry. A comparative study between resistant and susceptible host species

Most parasite-host relationships are characterized by the development of resistance by the host, thus limiting the number of parasites. However, some cases are very unusual. In the relationship of the domestic dog with the brown dog-tick Rhipicephalus sanguineus this does not occur, whereas guinea pigs develop efficient resistance. Sera from domestic dogs, crab-eating foxes and guinea pigs collected before and after infestation with R. sanguineus ticks, and after immunization with a whole tick adult or larval homogenate, were used in Western blot analysis to compare and identify potential important antigens from a tick larval homogenate. The same sera were tested in an indirect immunohistochemistry assay in an attempt to compare relevant antigenic sites on histological tick sections. The immunoblotting displayed antigens recognized only by the guinea pigs, as well as several shared antigens between host species, depending on the kind of immunization. Immunohistochemistry revealed probable antigenic sites on the cells and tissues of ticks, which varied depending on the kind of immunization (infestation or vaccination) and the animal species involved.

Control of parasitic infections among school children in the peri-urban area of Botucatu, Sao Paulo, Brazil

The prevalence of intestinal parasitosis was investigated in a primary school located in Rubiao Junior, a peri-urban district of Botucatu, Sao Paulo state, Brazil, in order to assess the effect of treatment and practical measures of prophylaxis in the control of parasitic infections among 7-to-18-year-old school children of a low socio-economic status. The first series of parasitological examinations included 219 school children, of which 123 (56.1%) were found to be infected with one or more parasite species. Eighty-four children carrying pathogenic parasites were submitted to various anti-parasitic treatment schedules. We re-evaluated 75 (89%) students after 4 to 6 months postchemotherapy. The results indicate that the combination of treatment with prophylactic measures has been successful in the control of parasitic infections, since reinfection rates were generally low (≤5.3%), except for Giardia lamblia infections (18.6%), and a marked reduction on the prevalence rates was observed with a significant percentage of cure (≤73.1%) in children infected with most parasite species. The reasons for the apparent failure in the control of infections caused by Hymenolepsis nana and Strongyloides stercoralis are discussed.

Intercontinental Differences in the Abundance of Solenopsis Fire Ants (Hymenoptera: Formicidae): Escape from Natural Enemies?

The absence of natural enemies often allows exotic pests to reach densities that are much higher than normally occur in their native habitats. When Solenopsis fire ants were introduced into the United States, their numerous natural enemies were left behind in South America. To compare intercontinental fire ant densities, we selected 13 areas in South America and another 12 areas in North America. Sample areas were paired with weather stations and distributed across a broad range of climatic conditions. In each area, we measured fire ant densities at 5 preselected roadside sites that were at least 5 km apart. At each site, we also measured foraging activity, checked for polygyne colonies, and recorded various kinds of environmental data. In most areas, we also measured fire ant densities in lawns and grazing land. Fire ant populations along roadsides in North America were 4-7 times higher than fire ant populations in South America. Similar intercontinental differences were found in lawns and on grazing lands. These intercontinental differences in fire ant abundance were not associated with sampling conditions, seasonal variability, habitat differences, or the frequency of polygyny. Although several correlations were found with long-term weather conditions, careful inspection of the data suggests that these correlations were probably more coincidental than causal. Cultural differences in roadside maintenance may explain some of the intercontinental differences in fire ant abundance, but they did not account for equivalent intercontinental differences in grazing land and mowed lawns. Bait tests showed that competition with other ants was much more important in South America; however, we were not able to determine whether this was a major cause of intercontinental differences or largely a consequence of other factors such as the numerous pathogens and parasites that are found in South America. Because this study was correlational, we were unable to determine the cause(s) of the large intercontinental difference in fire ant abundance that we observed. However, we were able to largely exclude a number of possible explanations for the differences, including sampling, season, polygyny, climate, and aspects of habitat. By a process of elimination, escape from natural enemies remains among the most likely explanations for the unusually high densities of fire ants found in North America.

Implicações da agregação espacial de parasitas para a dinâmica populacional na interação hospedeiro-parasita

Some aspects of the widely observed over-dispersed pattern of the distribution of parasites within the host population are examined. It has been established in the parasitological literature that most hosts usually harbour few parasites, while only few hosts harbour a large proportion of the parasite population. Factors that may influence the pattern of distribution of parasites, the relation between the level of parasite aggregation and the prevalence of infection, and changes in this level of aggregation as a function of host age are analysed. Factors which determine the diversity of species in parasite communities are presented, and aspects of exploitative and interference competition among parasites and their relations with biological control procedures are also considered. Attention is also focused on the regulatory and destabilizing processes influencing the dynamic behaviour of host-parasite population interactions.