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C Raccurt

Publications and source records attributed to C Raccurt.

At least 19 recordsLinked to original sources
PubMed2001

Trypanosomatidae from wild mammals in the neotropical rainforest of French Guiana.

The initial filling of the reservoir behind the Petit Saut hydro-electric dam, on the Sinnamary River in French Guiana, threatened the terrestrial and arboreal animals living in the neotropical rainforest being flooded. During a rescue programme between 24 October and 12 November in 1994, many of these animals were checked for infection with trypanosomatids. Overall, 45 blood samples and 54 skin biopsies were collected from 53 mammals (of 13 species representing five orders) and blood samples were also taken from each of nine reptiles (six species from four families). When the skin biopsies and the buffy-coats from the blood samples were cultured in NNN medium, 10 of the cultures, each initiated with mammalian blood, were found to be positive for trypanosomatids. Multilocus enzyme electrophoresis (MLEE) on cellulose acetate plates, with 20 enzyme systems, was then used to investigate each of the positive cultures. The results were analysed by clustering from a genetic distance matrix, using the unweighted pair group method with arithmetic averages (UPGMA), and applying a bootstrap procedure to Wagner parsimony trees. A stock obtained from Didelphis marsupialis was identified as a zymodeme of Trypanosoma cruzi (Miles' zymodeme 1) known to cause Chagas disease in French Guiana. Five stocks (one each from Bradypus tridactylus, Tamandua tetradactyla and Alouatta seniculus and two from Saguinus midas) were of a single zymodeme close to Trypanosoma rangeli reference stock RGB. This is the first confirmation of the presence of Tr. rangeli in French Guiana, and the first time that it has been identified, by iso-enzyme analysis, in the neotropical primates A. seniculus and S. midas. Two other stocks, isolated from Choloepus didactylus, were related to Endotrypanum schaudinni reference stock LEM 2790. Although the remaining stocks, one from C. didactylus and the other from A. seniculus, clustered together on UPGMA and in a Wagner tree, they did not appear to be related to any of the reference stocks included in the UPGMA dendrogram.

Animals↗
PubMed2000

Congestive heart failure and myocarditis after seroconversion for toxoplasmosis in two immunocompetent patients.

Two cases of myocarditis and congestive heart failure in immunocompetent patients with seroconversion for toxoplasmosis are reported. Serological tests showed that in the first case the cardiac manifestations occurred at the time of seroconversion (low IgG, raised IgM and IgA), whereas in the second case they occurred several months after the initial infection when IgM was decreasing, IgG levels were very high (>1000 IU/ml) and IgG had high affinity for the antigen. The pathophysiological mechanisms underlying cardiac involvement in acute or chronic toxoplasmosis are discussed.

Adult↗
PubMed1983

Comparative morphology of Mansonella ozzardi microfilariae from Colombia and Haiti. A light microscope study.

Comparative morphological studies were conducted at the light microscope level to determine whether any difference could be detected in thin smears, thick smears, or Knott samples, between Colombian (simuliid-transmitted) and Haitian (culicoid-transmitted) Mansonella ozzardi microfilaria. Results indicated that the microfilariae from these two geographical areas are essentially identical. The small differences observed in the dimensions of microfilariae in thick and in thin smears can be attributed to different preparative procedures. The consistent morphological differences, noted in PAS-hematoxylin-stained microfilariae, from Knott smears, was that the central body was thinner and stained less intensely with the Schiff reagent in the Haitian than in the Colombian microfilariae. Although these observations suggest a physiological difference between these two forms, additional studies are needed to exclude the possibility that these differences are not indications of the age or a state of physiological activity of the microfilariae.

Animals↗
PubMed1983

Ultrastructure of Mansonella ozzardi microfilaria, with a comparison of the South American (simuliid-transmitted) and the Caribbean (culicoid-transmitted) forms.

Ultrastructural studies conducted to elucidate and compare the microanatomy of the South American (simuliid-transmitted) and the Caribbean (culicoid-transmitted) microfilariae of Mansonella ozzardi revealed that these microfilariae are essentially identical. The only difference detected was the larger central body of the Colombian microfilariae. Although the microanatomy of M. ozzardi microfilaria is essentially the same as that of other microfilariae, some of the subtle differences noted between M. ozzardi and other microfilariae include: amphids of unequal lengths, a large nucleus located approximately 30 microns from the anterior end, and an esophagus which appears to be less developed than that of Loa loa and Brugia spp. The microfilaria has a small cephalic hook, intracellular bacteriae in the hypodermal cells, and crystalloid inclusions which are most prominent in the R-1 cell and are also present in the hypodermal and esophageal cells. These crystalloids appear to be unique to M. ozzardi microfilariae.

Animals↗
PubMed1982

Mansonella ozzardi in Haiti. III. A comparison of the sensitivity of four sampling methods in detecting infections.

A study to compare the sensitivity of four sampling methods in detecting Mansonella ozzardi among 133 inhabitants of Bayeux, Haiti, is reported. The Knott method proved the most sensitive with 40 microfilaria carriers detected. No additional infections were revealed by the other sampling methods. This was followed in order by 20 mm3 thick films of earlobe blood (34 cases), finger-prick blood (32 cases in the first sample), and skin biopsy (14 cases from paired samples). The combination of three finger-prick samples (60 mm3 of blood) detected 38 of 40 (95%) Knott-positive infections. The Knott method detected only one case not observed by at least one of the other three sampling methods. This sampling procedure did not detect more M. ozzardi in the 0-19-year age group than observed by the 20-mm3 finger prick method. Based on these results, a correction factor of 1.25 can be applied to our earlier Bayeux survey.

Adolescent↗
PubMed1981

Mansonella ozzardi in Haiti II. Arthropod vector studies.

The present vector studies show that the biting midge, Culicoides furens, serves as an intermediate host for Mansonella ozzardi in Haiti. A total of 3,430 C. furens were collected as they engorged on infected individuals. Under the maintenance conditions described herein, the microfilaria required 9 days to reach the infective stage. Approximately 43% of the midges survived, and from these 1,128 infective stage larvae were collected. This represents an overall infection rate of 0.76 larva per midge. Typically, there was a directly proportional relationship between the infection rate in midges and the level of microfilaremia in the individuals upon whom the C. furens fed. Also, the vector efficiency of C. furens collected from saltwater or freshwater breeding habitats was comparable.

Animals↗
PubMed1981

Susceptibility of laboratory primates to infection with Mansonella ozzardi from man.

The study was undertaken to determine primates were susceptible to infection with Caribbean and/or Amazon strains of Mansonella ozzardi of man. Twenty-three animals including three chimpanzees, four squirrel monkeys, one capuchin, five rhesus and 10 patas monkeys each received, by subcutaneous or intraperitoneal injection, 25-170 infective larvae of M. ozzardi harvested either from infected Culicoides furens collected in Haiti or Simulium sp. (sanguineum complex) collected in the Colombian Amazon and transported to our laboratories in Louisiana. Patent infections were obtained in seven of 10 patas monkeys but not in any other species of primates. The prepatent period ranged in duration from 149-186 days with a mean of 168 days. All of the patas monkeys developed modest microfilaremias that persisted for as long as 1 year, the duration of our observations. Adult worms were obtained at necropsy from three of four patas monkeys. The worms were recovered from soakings of the carcass and skin rather than from the abdominal cavity and mesenteries. However, their precise habitat was not determined.

Animals↗
PubMed1980

Mansonella ozzardi in Haiti. I. Epidemiological survey.

A survey of 1,165 inhabitants of Bayeux, Haiti revealed that 16% were infected with Mansonella ozzardi. This was determined from a single 20 mm3 sample of finger prick blood from each individual. Amont children and young adults (< 20 years of age), fewer than 2% had detectable microfilaremias. Beyond this age the prevalence of infection for males and females was 49% and 24%, respectively. The microfilariae circulate in the peripheral blood with no significant periodicity. In general, the microfilaremias were low, with 71% of the positive cases having less than 10 microfilariae in 20 mm3 of blood; only 4% had more than 50 microfilariae. Histological examination of sectioned skin biopsies showed that the microfilariae dwell within the superficial capillary vessels; not free in the extravascular tissues.

Adolescent↗