Biomedical subjects
Publications and source records attributed to G Chauvier.
The term "protistoma" is proposed to point at a variety of mammary tumor where the presence of a parasitic protist was revealed by culture and histological sections. When associated with one or more cells the protist gives rise to a xenoparasitical complex that intervenes in various ways in the tumorous process.
A relatively simple diphasic medium, the composition of which is given, allow the cultivation in vitro at 37 degrees C of the parasitic protist discovered in the genital system of Primates. From the study of the various cultural forms a first interpretation of the biological cycle of the parasite may be given.
Microcysts were first observed in histological sections of the placenta of a gibbon, the uterus of a Microcebus, showing a pyometra, the placenta, spleen and lung of a new born mangabey which died soon after birth from an interstitial pneumonia. Plasmodial forms were also discovered in the sections, either encysted or infiltrating the tissues. Cultures from all the above mentioned pathological material were attempted on a special medium, the composition of which will be given later. All cultures shew myxamoeba-like organisms aggregating and merging into pseudoplasmodial forms that produced microcysts. Attention is drawn to the pathogenic rôle of this new kind of parasites in order that they should be searched for, in every case of genital troubles not ascribable to other causes.
Two cases of ichthyophoniasis (ichthyosporidiosis) are reported for the first time in fish-eating birds, heron and herring gull. The lesions were mainly in the heart, liver, spleen and kidney. The fungus was isolated from them, cultivated and found identical to a strain previously obtained from a sea-fish. It was able to grow at 40 degrees C. Attention is drawn on the potential hazard for human health resulting from the ingestion of raw fish.
After comparison of the chromosomes of 42 species or subspecies belonging to Cercopithecinae, Papioninae and Colobidae, a phylogeny based on the sequence of chromosomal rearrangements is proposed for Cercopithecoidea. From their last common ancestor, which possessed 46 chromosomes, a trifurcation gave 3 branches, very unequal as regards chromosomal rearrangements. One, very short, leads to Papioninae. Another, still poorly known, leads to Colobidae. The last branch leads to a further bifurcation, separating 2 groups of Cercopithecinae, with underwent the most active chromosomal evolution. A tentative to reconcile chromosomal, biochemical and morphological data is presented for Papioninae, for which chromosome study alone is not sufficient to construct a cladogram.
Chromosome analysis by handling techniques of 19 species and sub-species of Cercopithecinae shows an important accumulation of chromosome rearrangements (51). With a clear predominance of fissions (26) and of inversions (17). It is impossible to reconstruct a simple genealogy of these species because chromosomal evolution did not follow the principle of a strict dichotomy. The progressive increase of the number of chromosomes, by fission, corresponds to the inverse of the Robertsonian evolution and suggests the existence of numerous interstitial centromeres and telomeres.
Chromosome banding patterns of six Mangabey species or sub-species are studied and compared. By comparison with the other Papiinae previously studied (Papio and Macaca) Lophocebus albigena and L. aterrimus possess very similar karyotypes, differing a most by a pericentric inversion of the Y chromosome. The other four, Cercocebus torquatus torquatus, C. t. fuliginosus, C. galeritus galeritus and C. g. chrysogaster differ by a complex rearrangement of chromosome no. 10 and by acquisition of heterochromatin on chromosome no 12. No difference was detected nor between the two Lophocebus nor between the four Cercocebus. Cytogenetic criteria age thus in agreement with the morphological, immunological and hematological data, separating the two genuses, and placing Lophocebus closer to the Papio and Macaca than to Cercocebus.
The karyotypes of two Lorisidae (Prosimians) Nycticebus coucang and Perodicticus potto have been studied, using many banding techniques. These karyotypes are compared with each other and also with those of Microcebus murinus (Lemur) and of Cebus capucinus (Simian, platyrrhine). The karyotype of M. murinus appears ancestral to the other. That of the Lorisidae cannot be an intermediatry stage between the karyotypes of the lemurs and of the simians. An important part (12 p. cent) of the genome of N. coucang is comprised of heterochromatin ; it and the juxta centromeric heterochromatin stain negatively with C-banding techniques. C-banding therefore is insufficient to delineate constitutive heterochromatin, late replication being the only universal criterion.
The karyotypes of four species of Cercopithecidae: Cercopithecus aethiops tantalus, C. sabaeus, Erythrocebus patas, and Miopithecus talapoin are analysed with nearly all the banding techniques. They are compared with each other, and with the karyotypes of the Baboon P. papio and with that of man. It can be concluded that the quasi-totality or the totality of the euchromatin is common to all, but has undergone structural rearrangements, generally detectable. The heterochromatin, defined by C-band staining, and late-replicating DNA, in contrast, appears very variable: In particular, E. patas has acquired very large heterochromatic segments. The significance of these modifications is discussed.
The karyotypes of Cebus capucinus and C. nigrivittatus (Primates, Platyrrhini) are compared after applying several banding techniques. The chromosomes have abundant intercallary heterochromatin which can be stained by R-, T- and C-band techniques and which are late replicating. The X chromosome resembles that of man and of numerous primates. However, the late replicating pattern of the X in female lymphocytes resembles that of the late replicating X of human fibroblasts rather than of human lymphocytes. Banding patterns of certain chromosomes appear analogous in Cebus and Cattarhini, including Man.
Fourteen cases of a systemic mycosis in ornamental fresh-water tropical fishes are recorded. Clinical signs, cystic lesions in the liver and spleen, recall those of an infection by the fungus Ichthyophonus, or Ichthyosporidium hoferi. The possibility that the fresh-water fishes' parasite might be of a different species is discussed. Morphological aspects of the yeast-like fungus in culture are described.
The most frequent tinea of the subhuman Primates are microsporosis due to Microsporum canis or trichophytosis at Trichophyton mentagrophytes and T. simii. The T. mentagrophytes, an anthropo-zoophilic species must be differenciated from T. rubrum and T. interdigitale, dermatophytes of the man; due to the importance of that diagnosis in Primate mycology, some tests are used for the differenciation. Between the 226 monkeys investigated it was registered: 2 trichophytosis at T. mentagrophytes (an onychosis in a Cebus capucinus and a back-skin implantation in a Cercopithecus mona campbelli) and 13 cases of pseudo-dermatophytosis cutaneous disorders. From 40 of the 221 healthy subjects were discovered 14 porteur monkeys of keratinophilic fungi (2 T. terrestre, 1 Keratinomyces ajelloi, 5 Chrysosporium keratinophilus and 7 Chrysosporium sp.). The question of the alopecia of the Primates, without isolating a dermatophyte, was discussed.
In pure culture the parasitic fungus isolated from fish shows a remarkable peculiarity for it can: a) exhibit caryogamy in dicaryotic elements that are either small yeast-like cells or short mycelial tubes expanding from larger yeasts; b) conjugate two yeastlike circular isogametes and produce thereafter an oocyst in which endospores take form; c) merge two hyphae expanding from two round cells and produce by means of this somatogamous process a sporangium in which endospores take form.