[Etiology of the first African case of systemic blastomycosis].

Several authors have suggested that african and north american forms of Blastomyces dermatitidis appeared separate taxa. Morphologic and pathogenic differences not only prevail, but also the failing to mate between them. African forms lose their mycelium-yeast conversion capability in old cultures.

[Argas and arbovirus update].

At the opportunity of the recent discovery of a new Phlebovirus, Tunis virus, the authors discuss the importance of the genus Argas as for its potential role in the transmission of arboviruses: twelve species of Argas are known to carry about twenty viruses. The wide distribution of Argas reflexes hermanni prompt us to explain its position in the Argas reflexes "complex" group: this species seems to be more liable to infection by viruses. Some ecological and entomological data are added to facilitate its typing.

[Tick-transmitted arbovirus in Maghreb].

The problem of arbovirus infections in Maghreb has been relatively neglected in the pst in spite of a rich diversity of biotopes, the presence of potential reservoirs and vectors, and their position on the flight path of the Palearctic-african bird migration systems, western branch. Moreover, West Nile virus has been isolated from southern Algeria since 1968. From 1979 to 1989, ticks were collected from wild birds, pigeons, bats, rodents, poultry, camels, wild boars, domestic mammals and man, and assayed for viruses.

Tunis virus: a new Phlebovirus from Argas reflexus hermanni ticks in Tunisia.

A new Phlebovirus provisionally named Tunis virus has been isolated from Argas reflexus hermanni ticks parasitizing domestic pigeons. It is the first isolation of an arbovirus from Tunisia and the fourth tick-borne virus to be isolated from the Moghreb following Soldado, Essaouira and Kala Iris in Morocco. The pathogenic potential of this virus is briefly discussed according to the behaviour of its vector and previous serosurveys in the country.

[Does Boutonneuse fever in France have equivalents outside the Mediterranean area?].

In western of France, outside of mediterranean spotted fever area, several sera from autochthonous patients were positive for the presence of anti-R. conori antibodies by indirect immunofluorescence test. What is it all about: authentic rickettsiosis or paraspecific seroreactions with other microorganisms? We discuss these hypothesis.

[The stimulation of tumoricidal peritoneal macrophages can be directly induced by peritoneal implantation of unicellar algae in humans].

The authors explain by what means they have been conducted to use the anti-tumoral power shown by the peptido-glycans produced in the wall of unicellular algae. The first human trials when the algae are introduced in the peritoneal cavity have shown a good tolerance.

[Babesiasis, pediatric malaria: does confusion exist in Africa?].

The authors describe a case of febrile disease acquired by a nursling in Africa: was it induced by Pl. falciparum or by Babesia sp.? In spite of numerous microscopic and serological appraisals from veterinary and medical authorities, it is difficult to state definitively this subject, but it is more probably a babesiosis of canine or rodent origin.

[Specificity in the relationship between Salmonella typhimurium and Schistosoma mansoni].

Special interaction between Salmonella typhimurium (STM) and Schistosoma mansoni is considered under two complementary aspects, in vivo and in vitro, using scanning and transmission electron microscopy. The resulting observations have obviously permitted us to discover a large specificity in these adhesion phenomena that seems to lead to the fusion of membranes between the two organisms. Microanalysis trials executed in these areas of strong affinity were attempted.

[Use of scanning electron microscopy coupled with transmission electron microscopy in comparative studies of the relation between Schistosoma mansoni and Salmonella typhimurium].

Relations between Schistosoma mansoni and Salmonella typhimurium are studied in vivo and in vitro using scanning and transmission electron microscopy as complementary methods. Salmonellae adhesion is a specific process materialized in special places of male and mature schistosome tegumental surface. Interactions are marked by bacterial strong fibres creating a network all around Schistosoma where Salmonellae are dividing.

[Studies in vivo and in vitro on relations between Schistosoma mansoni and some enterobacteria strains].

Studies performed in vivo and in vitro, using scanning electron microscopy, on relations between Schistosoma mansoni and some enterobacteria show a strong association for certain bacterial strains (Salmonella typhimurium). Salmonellae adhesion on tegumental surface of male and mature Schistosoma is only possible in vitro owing to bacterial synthesis of strong fibres penetrating inside the worm. These interactions are not found with Escherichia coli, Proteus mirabilis or with young schistosomula.

[Attempts at demonstrating the Schistosoma-Salmonella relationship. In vivo and in vitro studies].

The optical microscopy (on histological preparations) and scanning observations of Schistosoma mansoni is conducted in the presence of various species of Salmonella. It is well-obtained that the Schistosoma maturity, its metabolic activity and the action of antibodies anti-salmonella have influenced the bacterian fixation on the worm. An hypothesis about the possible mechanism of this attachment is then developed and also an hypothesis about the protection of bacteria against antibiotherapy among patients infected with Schistosoma and carriers of salmonellosis.

[New contribution on Dipetalonema viteae. Keeping adults alive in vitro. Scanning electron microscope study of the development of embryos and young larvae L1 and L2].

The adult stages of Litosomosoides carinii, Dirofilaria uniformis and Dirofilaria immitis have been successfully maintained in vitro though microfilaria production by the worms continued only for a period of one to 18 days. In this paper we describe the results obtained in a series of experiments in which adult L1 and L2 stages of Dipetalonema viteae were maintained in vitro.

[Gilchrist's disease and fungal taxonomy: a thorny problem].

The study of iconographical data and of six american and african strains of B. dermatitidis allows us to conclude that there are several discriminating characters between the members of the Blastomyces dermatitidis complex. The african strains are distinguished by the lack of sexual forms and old strains show the lost of the M lead to Y conversion.

[Possible transfer between sarcomatous mouse cells (BP8) and yeasts (Saccharomyces cerevisiae, whole bodies and protoplasts)].

From our observation in vitro, we can suggest that : a direct contact between sarcomatous cells and physiologically active yeasts appears to be necessary for the transfer of the radioactive labelling; the presence of a filter with pores of 1.2 micrometer diameter prevents passage of fragments of DNA or RNA between the cells; this transfer is a very small fact, but implies about the third of the yeasts.

[New approach to the study of the experimental inhibitory effect of the unicellular alga Chlorella pyrenoidosa against the murine sarcomas BP8 and L1210].

In this paper, the authors are relating the inhibitory effect of the unicellular alga Chlorella (Beijerinck, 1890) pyrenoidosa Zeitler and Lund, against the tumoural rodent strains BP8 and L1210, according to the amount of inoculum. The statistical study of the results allows to the conclusive fact of a real protective effect showed by this microorganism and of a demonstrative relation between the amount of the protective material and the tumoural answers the high amount giving a better inhibitory effect. The workers also insist on the lack of pathogenicity presented by the alga used in this study.

[Dipetalonema viteae larva studied by scanning electron microscopy].

If the description in the literature is based on a study with the light microscope, in this work, with electron microscope scanning, the integumental surface on the larva of Dipetalonema viteae is studied at 1,500 to 50,000 magnifications.

[Release of "Saccharomyces cerevisiae" protoplasts: scanning electron microscope study (author's transl)].

In a previous study we described the minimal methodology used to obtain protoplasts from ascomycetous yeasts. Using a reducing agent associated with 1,3-beta-glucanase at 26 degrees C, protoplasts were invariably obtained. In the present study we localized the disruption spots of the cell wall using the two same reagents.

[Autochthonous amebiasis in the region of Nantes].

A retrospective study on amoebiasis observed in the central hospital in Nantes since twenty years, shows that, at least, 16 % of the intestinal cases and 1/6, 5 of 30 cases of hepatic amoebiasis are autochthonous.