PubMed Health⌕ Search

Biomedical subjects

C Roux

Publications and source records attributed to C Roux.

At least 19 recordsLinked to original sources
PubMed2025

One mother for two species via obligate cross-species cloning in ants.

Living organisms are assumed to produce same-species offspring1,2. Here, we report a shift from this norm in Messor ibericus, an ant that lays individuals from two distinct species. In this life cycle, females must clone males of another species because they require their sperm to produce the worker caste. As a result, males from the same mother exhibit distinct genomes and morphologies, as they belong to species that diverged over 5 million years ago. The evolutionary history of this system appears as sexual parasitism3 that evolved into a natural case of cross-species cloning4,5, resulting in the maintenance of a male-only lineage cloned through distinct species' ova. We term females exhibiting this reproductive mode as xenoparous, meaning they give birth to other species as part of their life cycle.

Animals↗
PubMed1979

Teratogenic action and embryo lethality of AY 9944R. Prevention by a hypercholesterolemia-provoking diet.

Embryomortality and teratogenesis provoked by inhibitors of cholesterol synthesis are well demonstrated. Teratogenic action is particularly reflected by holoprosencephalies, but also by uro-genital abnormalities. A hypercholesterolemia-provoking diet has been shown to be completely effective for preventing holoprosencephaly, but only partially so for preventing the uro-genital malformations and fetal mortality. It is thus possible that the two types of abnormalities are governed by different mechanisms. In addition, the diet itself, whose hypercholesterolemic effect is considerable, has certain disadvantages. It seems to have a certain effect on fetal mortality and could be responsible for several uro-genital malformations. This deserves further study.

Abnormalities, Drug-Induced↗
PubMed1979

Interpretation of isolated agenesis of the pituitary.

Cholesterol synthesis inhibitors administered to rats caused more or less complete forms of the holoprosencephalic syndrome, consisting of severe abnormalities of the brain, sense organs and pituitary. The absence of the pituitary was also observed in fetuses without externally visible cephalic abnormalities. These observations suggest that the isolated absence of the pituitary is the lesser form of the holoprosencephalic syndrome. This interpretation is also valid for cases of isolated absence of the pituitary observed in humans.

Abnormalities, Drug-Induced↗
PubMed1978

A case of ring Y chromosome.

Ring Y chromosome 45,X/46,X,r(Y) was identified by fluorescence in a child with ambiguous external genitalia, urogenital sinus, vagina, uterus, and Fallopian tubes. Testicular tissue was noted on gonadal biopsy.

Disorders of Sex Development↗
PubMed1978

[Balanced translocations with abnormal phenotype (author's transl)].

Four cases of balanced translocations with phenotype abnormalities are reported. Three of them are reciprocal translocation, one is a Robertsonnian translocation. The consequences of the phenomene on genetic counselling and prenatal diagnosis are discussed.

Abnormalities, Multiple↗
PubMed1977

[Teratogenic action of an inhibitor of cholesterol synthesis in Wistar and Sprague-Dawley rats].

Sprague-Dawley rats are sensitive to the teratogenic action of AY 9944, an inhibitor of cholesterol synthesis, but the dose of inhibitor necessary to induce the same rate of characteristic malformations is twice as large for Sprague-Dawley as for Wistar rats. This variation is probably related to differences in levels of blood cholesterol in the strains and demonstrates a relationship between teratogenicity and metabolic disturbances.

Animals↗
PubMed1977

[Taxonomic characters of "Clostridium tyrobutyricum" (author's transl)].

The taxonomic characters of 77 strains of Clostridium tyrobutyricum have been studied and compared to those of known strains. This work shows the insufficiency of the Bergey's Manual (8th edition) nine characters distinguishing Clostridium groupe I to identify C. tyrobutyricum. To be more representative of the species, addition of one or two characters to this key of determination and some modifications to the complementary description of C. tyrobutyricum in this manual are proposed.

Carbohydrate Metabolism↗
PubMed1976

[Toxoplasmosis and pregnancy. Evaluation of 2 years of prevention of congenital toxoplasmosis in the maternity ward of Hôpital Saint-Antoine (1973-1974)].

The authors report the results of prophylaxis of congenital toxoplasmosis in a maternity hospital in Paris for a two years period (1973-1974). 6269 pregnant women were surveyed. 18 toxoplasmosis were detected in evolution at the first prenatal examination, 10 seroconversions were identified among the first examination antibody negative women, when re-examined during the pregnancy. 25 of these 28 women were treated regularly. The seroconversions of the 3 other women were detected only at delivery. In addition 25 women were treated because of high antibody titers (Dye-Test greater than or equal to 300. U.I/ml). 6 congenital toxoplasmosis, 2 of them were manifest, were observed among the children whose mothers were treated for confirmed toxoplasmosis. The extremely low level of seroconversions may be in relation to hygienic and dietetic prescriptions. The difficulties of this prophylaxis are analysed: they are due to studied population and to problems of interpretation or serologic examinations.

Female↗
PubMed1975

Chromosomal abnormalities in maternal and fetal tissues of magnesium- or zinc-deficient rats.

The effect of dietary deficiency during pregnancy of zinc or magnesium on maternal and fetal chromosomes was studied. Pregnant rats were given a zinc-deficient or a magnesium-deficient diet from the beginning of pregnancy and maternal bone marrow and fetal liver were removed on day 19 of gestation. Chromosome spreads were prepared and metaphases examined for abnormalities. Both magnesium- and zinc-deficient maternal bone-marrow and fetal liver cells showed significantly more chromosomal abnormalities than did those of controls. The chromosomal aberrations occurring in highest incidence in magnesium-deficient animals were terminal deletions and fragments. A higher than normal incidence of "stickiness" was also observed in cells from magnesium-deficient animals. In zinc-deficient animals, on the other hand, the chromosomal aberrations with the highest incidence were gaps and terminal deletions.

Animals↗