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J B Mailhes

Publications and source records attributed to J B Mailhes.

49 records · Page 3Linked to original sources
PubMed1987

Cytogenetic analysis of mouse metaphase II oocytes following exposure to tritiated water.

Female mice were given different dosages (0, 3.0, 7.5, 15.0, or 30 muCi/ml) of tritium in their drinking water continuously from 3 to 7 weeks of age to assess the effects on germ cell chromosomes. At 8-9 weeks of age, mice were superovulated and metaphase II oocytes were processed and C-banded for cytogenetic analyses. Chromatid acentric fragments were the only type of structural aberration detected, and their incidence was higher in controls than in any of the tritiated water (HTO) groups. Analysis of numerical chromosomal aberrations revealed that the incidence of hypoploid (N = 19) oocytes was higher in oocytes from mice who drank HTO as compared with controls. However, the effects of HTO upon aneuploidy induction was not definitive due to the increase the incidence of aberrations in mouse oocytes can be related to the low dose rate resulting from chronic HTO exposure and possibly death of tritium-damaged cells.

Animals↗
PubMed1985

Syrian hamster lymphocyte cytogenetic technique and effects of blood storage on mitotic index.

The Syrian hamster has a diploid chromosome complement similar to humans in both number (2N = 44) and morphology. For comparative mutagenic studies with humans, a repeatable lymphocyte chromosome technique involving laboratory mammals is desirable. The reported hamster lymphocyte cytogenetic technique appears technically uncomplicated and repeatable while providing a sufficient number of metaphase cells for quantitative analysis. In order to determine the effects of storing whole-blood (in culture media) for varying time periods at 8 degrees C prior to adding a mitogen, the mitotic index was calculated following a 48-h culture period. Results indicated that storage up to six days can still result in a mitotic index adequate for cytogenetic analyses.

Animals↗
PubMed1983

Methylmercury effects on Syrian hamster metaphase II oocyte chromosomes.

Methylmercury (MM) denatures DNA and can induce chromosomal aberrations. In addition, it destroys microtubules and increases the incidence of aneuploidy and mitotic arrest. Although MM is distributed to gonads, data relating the cytogenetic effects of MM on mammalian germ cells in vivo have not been found. To determine whether MM increases the incidence of cytogenetic damage in oocytes, Syrian hamsters were divided into three groups: (1) negative controls; (2) positive controls, 0.25 mg Trenimon (T)/kg; and (3) 10 mg methylmercury chloride (MMC)/kg. Superovulation was utilized and metaphase II oocytes analyzed for numerical and structural chromosome aberrations. A highly significant (P = .015, Fisher's exact test) difference in the incidence of hyperploid (N = 23) oocytes was obtained between negative controls (0/150) and the MMC group (6/150). The incidence of hypoploid (N = 21) oocytes in negative controls and the MMC group was 12/150 and 21/150, respectively (P = .069). Structural aberrations were not observed. Of 281 oocytes analyzed in the T group, 42.7% had structural aberrations. These results primarily indicate that MMC increases the incidence of hyperploidy and not structural aberrations.

Animals↗
PubMed1979

Omphalocele and partial trisomy 1q syndrome.

A male infant with partial trisomy 1q syndrome (46,XY,der(21),t(1;21)(q25;q22)pat) is described. Clinical findings include small for gestational age, hypoglycemia, ocular hypertelorism, microphthalmia, coloboma of the iris, low-set ears, beak nose, micrognathia, micropenis, cryptorchidism, presacral dimple, flexion contractures of the fingers, bifid thumb, Simian crease, and overriding toes. In addition, he had a large omphalocele not previously seen in trisomy 1q. Postmortem findings include underdeveloped cerebellum, a thymus with moderate depletion of thymocytes, a large PDA, ASD, small adrenal, and fatty change of the liver. The grandfather, father, and a male sibling have translocation t(1;21)(q25;q22). A family history of repeated spontaneous abortions is present.

Abnormalities, Multiple↗
PubMed1979

H-Y antigen-positive male pseudohermaphroditism with 45,X/46,XYq-mosaicism.

A 42-year-old male had short stature, microphallus, hypospadias, a bifid scrotum, abdominal undifferentiated testes, a uterus, bilateral fallopian tubes, and 45,X/46,XYq-mosaicism in his blood, skin, and germinal tissue and tissue surrounding the tests as determined by means of G-, Q-, and C-banding. An H-Y antigen assay on skin fibroblasts was positive, indicating that the locus for this antigen is not located in the brightly fluorescent region of the Y chromosome.

Adult↗
PubMed1975

Comparison of chromosome breakages in lymphocytes and fibroblasts from control women and women taking oral contraceptives.

To determine whether exposure to synthetic hormones resulted in increased chromosome damage in cells other than lymphocytes, we evaluated series of lymphocyte and fibroblast cultures from five control women and five women taking oral contraceptives (OC). The results of this study showed: (1) no difference in chromosome breakages between lymphocytes and fibroblasts; (2) no differences in breakages in replicate fibroblast cultures exposed to fetal calf serum, autologous serum, homologous serum, or homologous serum from OC users; (3) no difference in breakage between lymphocyte and fibroblast cultures from OC users, compared with lymphocyte and fibroblast cultures from control women; and (4) no increase in the frequency of cytogenetically aberrant stem-lines in fibroblast cultures from women taking OC. These findings suggest that synthetic hormones do not cause increased chromosome breakages in fibroblasts from women taking OC.

Adult↗
PubMed1975

Toxicology of octabromobiphenyl and decabromodiphenyl oxide.

Decabromodiphenyl oxide (DBDPO) and octabromobiphenyl (OBBP) perform well as fire-retardant additives for thermoplastics. Both compounds have low acute oral toxicity and low skin absorption toxicity. They are neither primary skin irritants or skin sensitizers and are only mildly irritating to the eyes. A 30-day dietary feeding study in rats established 8 mg DBDPO/kg-day as an unequivocal no-effect level and 80 mg/kg-day as a marginal effect level. A no-effect level was not established for OBBP in a comparative study. A 2-yr rat study providing 0.1 mg DBDPO/kg-day in the diet revealed the bromine concentration reached a plateau in the liver within 30 days, while the concentration in adipose tissue slowly increased. A comparable OBBP study revealed bromine concentration in the liver and adipose tissue increased steadily and rapidly with no attainment of a plateau during 180 days of the study. Neither compound produced an accumulation of bromine in other tissues. After administration of 14C DBDPO, all 14C activity was eliminated via the feces within 2 days. After administration of 14C OBBP, 62% was eliminated with a half-life of less than 24 hr; the half-life for the remainder was greater than 16 days. In a teratology study, 10, 100, or 1000 mg DBDPO/kg-day had no effect in rats. Reproductive capacity of rats was not effected at 3, 30, or 100 mg DBDPO/kg-day. No effects were observed on cytogenetic examination of bone marrow cells of parents and weanlings from the reproduction study.

Abnormalities, Drug-Induced↗
PubMed1975

Observations of de novo clones of cytogentically aberrant cells in primary fibroblast cell strains from phenotypically normal women.

In a recent study of chromosome breakage frequencies in 36 primary fibroblast cell strains derived from skin from 10 phenotypically normal women, we observed seven different clones of cells having consistent chromosomal abnormalities. Five of the stem lines were noted in cultures from "control" women and two in fibroblasts from women taking oral contraceptives. We observed aneuploid clones as well as stem lines bearing structural abnormalities (e.g., translocation, inversions). The various aberrant clones were found in cultures ranging in age from 41 to 144 days and comprised varying percentages of the cell populations ranging from 0.8% to virtually 100%. The possible evolution in culture of clones of cells having aberrant karyotypes should be considered in interpreting findings from fibroblast cultures initiated for clinical evaluation.

Cell Division↗
PubMedDate not supplied

Mammalian in vivo assays for aneuploidy in female germ cells.

This paper presents an evaluation of and offers recommendations for assays to detect chemically induced aneuploidy in mammalian female germ cells. 72 papers on female germ cell aneuploidy, published from 1970 to 1984, were reviewed. 28 papers were selected for critical evaluation; the other 44 papers were rejected according to pre-established criteria. Salient points emerging from the information reviewed allow an assessment of the current status of mammalian female germ cell tests for aneuploidy. The majority of data have been obtained by analyzing metaphase II mouse oocyte chromosomes following superovulation. Various classes of chemicals were administered usually around the time of ovulation. Dose-response relationships have not been obtained for the majority of chemicals evaluated. The method of data reporting and analysis usually was not conducive to comparisons among different studies. Few of the 16 chemicals studied can be regarded as negative for their ability to induce aneuploidy, whereas an even smaller number should be considered as positive. Certainly, a need exists to identify the chemicals and the dosages that could increase the incidence of aneuploidy in mammalian female germ cells. Obtaining such data definitely is feasible in cytogenetic laboratories. However, the mammalian female germ cell aneuploid assay should not be perceived as a rapid, inexpensive, routine procedure. The assay is capable of detecting aneuploidy following anaphase I when metaphase II oocytes are studied and following anaphases I and II when first-cleavage zygotes are studied.

Aneuploidy↗