Anopheline species, some of their habits and relation to malaria in endemic areas of Rondônia State, Amazon region of Brazil

In view of recent studies incriminating several species of anophelines, besides Anopheles darlingi, as malaria vectors in the Brazilian Amazon, we performed an anopheline survey in four localities - Ariquemes, Cujubim, Machadinho and Itapoã do Oeste - in Rondônia, the most malarious State in the Country. Twenty species were found. An. darlingi was, by far, the dominant species and the only one whose density coincided with that of malaria. On human baits it was more numerous in the immediate vincinity of houses than indoors whre, however, it was almost the only species encountered. On both situations it fed mostly at sunset and during the first half of the night. It was less numerous far from houses and scarce inside the forest. Other species (An. triannulatus, An. evansae, An. albitarsis, An. strodei) appeared in appreciable numbers only in Ariquemes, both in areas with and without malaria. The remaining species were scanty. An. darlingi was confirmed as the primary local vector.

Digamacris n. gen. (Orthoptera, Acrididae, Melanoplinae) de la region atlantica meridional de Brasil

Digamacris, a new genus of the Dichroplini (Acrididae, Melanoplinae) is described for the species Pezotettix amoenus Stal, 1878 and Dichroplus fratemus Carl, 1916, both included at present in the genus Dichroplus. These species live in edges and clearings of the Atlantic Forest (Mata Atlantica) of Brazil. D. fratemus is found in the states of Minas Gerais, Espirito Santo and Rio de Janeiro east of the Bay of Guanabara. D. amoenus in the state of Rio de Janeiro W. of the Bay of Guanabara and in the coastal area of the state of São Paulo. The species are illustrated and redescribed. Both have two neatly different chromatic forms of females, while the males are uniform in coloration and closely correspond with one of the female forms.

Sarcopromusca pruna (Diptera: Muscidae) as an egg transport host of Dermatobia hominis (Diptera: Cuterebridae) in the cacau region of Bahia, Brazil

Sarcopromusca pruna appears to be the predominant transport host for Dermatobia hominis eggs among cattle herds in central eastern Bahia, Brazil. In the study area, two seasonal peaks of S. Pruna abundance coincide with those of Dermatobia, from mid July through late September and from mid November until early January, two periods of moderate monthly rainfall between anual extremes. Among more than 26,000 flies examined during the study, 75 (all female S. pruna) bore Dermatobia eggs. Certain aspects of Dermatobia behavior and ovoposition habits in the field are also discussed.

Prevalence of human T cell leukemia virus-I (HTLV-I) antibody among populations living in the Amazon region of Brazil (preliminary report)

Forty-tree (31.4%) out of 137 serum samples obtained from two Indian communities living in the Amazon region were found to be positive for HTLV-I antibody, as tested by enzyme-linked immunosorbent assay (Elisa). Eighty-two sera were collected from Mekranoiti Indians, yielding 39% of positivity, whereas 11 (20.0%) or the 55 Tiriyo serum samples had antibody to HTLV-I. In addition, positive results occurred in 10 (23.2%) out of 43 sera obtained from patients living in the Belem area, who were suffering from cancer affecting different organs. Five (16.7%) out of 30 Elisa positive specimens were also shown to be positive by either Western blot analysis (WB) or indirect immunogold electron microscopy (IIG-EM).

A new species of Cullex (Melanoconion) from the Amazonian Region (Diptera: Culicidae)

Culex (Melanoconion) eknomios, a new species from Amazonian region is described, including the adult, pupal and larval stages. Available data about distribution and binomics are presented.

Life history studies of heterophyid Trematodes in the neotropical region: Ascocotyle (Leighia) hadra sp.n

The life cycle of Ascocotyle (Leighia) hadra n.sp. was experimentally reproduced, starting from cercariae from naturally infected Littoridina parchappei, collected from Los Ranchos stream, near Mercedes city, Buenos Aires Province, Argentina. Metacercariae were found encysted in the liver and mesentery of experimentally and naturally infected fishes Cnesterodon decemmaculatus and Jenynsia lineata. Adults were obtained experimentally in chicks and mice. The natural host is unknown. The new species is compared with Ascocotyle (Leighia) mcintoshi Price 1936 as described by Leigh, 1974, differing in behavior and morphology of cercarial, metacercarial and adult stages

Two new species in the genus Cucullanus (Nematoda - Cucullanidae) from the australian region

Two new species of Cucullanus are described: C. bourdini n. sp. and C. laurotravassosi n. sp. C. bourdini is a parasite of Pristipomoides filamentosus , Aprion virescens and P. flavipinnis (Lutjanidae) in New Caledonia. The species is closely related to C. amadai, C. bulbosus and C. hians by the disposition of the post-and ad-cloacal papille but differs by the more posterior position of the deirids. C. laurotravassosi n. sp., a parasite of Arius sp. in Australia, is close to C. bagre but can be distinguished by the more posterior position of post-cloacal papillae.

Human IgG responses against the N-terminal region of Merozoite Surface Protein 1 of Plasmodium vivax

The complete primary structure of the gene encoding the Merozoite Surface Protein 1 of Plasmodium vivax (PvMSP-1) revealed the existence of interspecies conserved regions among the analogous proteins of other Plasmodia species. Here, three DNA recombinant clones expressing 50, 200 and 500 amino acids from the N-terminal region of the PvMSP-1 protein were used on ELISA and protein immunoblotting assays to look at the IgG antibody responses of malaria patients from the Brasilian amazon region of Rondônia. The results showed the existance of P. vivax and P. falciparum IgG antibodies directed against PvMSP-1 antigenic determinants expressed in the clones containing the first 200 and the following 500 amino acids of the molecule, but not within the one expressing the most N-terminal 50 amino acids. Interestingly, there was no correlation between the levels of these IgG antibodies and the previous number of malaria infections.

V-region-related and -unrelated immunosupression accompanying infections

This paper discusses current evidence for the relationship between polyclonal lymphocyte activation, specific immunossupression with decreased resistance, and autoimmune pathology, that are all often found associated with infections by a variety of virus, bacteria and parasites . The central question of class determination of immune effector activities is considered in the context of the cellular targets for nonspecific mitogenic activities associated with infection. A model is presented to integrate these findings: mitogenens produced by the microorganism or the infected cells are preferentially active on CD5 B cells, the resulting over-production of IL-10 will tend to bias all immune activities in to a Th-2mode of effector functions, with high titers of polyclonal antibodies and litle or no production of gamma IFN and other "inflamatory"lymphokines that often mediate resistance. In turn these conditions allow for parasite persistence and the corresponding long-term disregulation of self-directed immune reactivities, resulting in autoimmunity in the chronic phase. This model would predict that selective immunization with the mitogenic principles involved in desregulation, could stand better chances than strategies of vaccination based on immunopotentiation against othere, functionally neutral antigenic epitopes. It is argued, however, that the complexity of immune responses and their regulation together with our ignorance on the genetic controls of class-determination, offer poor prospects for a scientifically-based, rational development of vaccines in the near future. It is suggested that empirically-based and technologically developed vaccines might suceed, while basic scientific approaches are reinforced and given the time provide a better understanding of those process.

Epidemiological aspects of American Cutaneous Leishmaniasis in a periurban area of the metropolitan region of Belo Horizonte, Minas Gerais, Brazil

In order to characterize the epidemiology of American Cutaneous Leishmaniasis (ACL) in a periurban area of the municipality of Sabará in the metropolitan region of Belo Horizonte (MRBH), an area until then considered free of the disease, a cross sectional survey was undertaken in 1990. The survey of the population consisted of 1119 interviews and 881 clinical examinations using Montenegro's skin test (MST). A low prevalence (3.7%) of positive MST was encountered. The disease had been occuring in the area for about 20 years in the form of sporadic cases. The predominant species of sandfly both in domestic areas and nearby areas of secondary vegetation was Lutzomyia whitmani. A canine survey of delayed hypersensitivity to the antigen P10,000 identified only one dog with a positive reaction out of 113 examined. The transmission of ACL in MRBH was confirmed. The occurrence of the disease in women, children and individuals with no contact with forest areas as well as the presence of potential vector species in the domiciliar environment, suggests the transmission of the disease in this environment.