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B Dutrillaux

Publications and source records attributed to B Dutrillaux.

At least 253 records · Page 14Linked to original sources
PubMed1989

Cytogenetic characterization of a colon adenocarcinoma from a familial polyposis coli patient.

We report on the cytogenetic findings in a fresh biopsy of a colorectal adenocarcinoma in a patient with familial polyposis coli (FAP). The stemline had 45 chromosomes with several clonal chromosome aberrations including a der(17)t(17;?), and -18, which are the two most recurrent aberrations in sporadic colorectal carcinomas. This finding is discussed in relation to the chromosomal changes described in sporadic colorectal carcinomas and in FAP cell lines.

Adenocarcinoma↗
PubMed1989

Mapping of single-copy DNA sequences on human chromosomes by in situ hybridization with biotinylated probes: enhancement of detection sensitivity by intensified-fluorescence digital-imaging microscopy.

Two single-copy DNA segments of 6 kilobases (kb) and 2.3 kb were labeled with biotin-labeled dUTP (Bio11-dUTP) and hybridized to human chromosomes. These probes were detected by immunofluorescence and directly mapped on chromosomes by using classical fluorescence microscopy and a microchannel-plate-intensified video camera. By a subsequent R-banding, the 6-kb and 2.3-kb fragments were precisely localized to the 18p11.3 band and to the 22q11.2 band, respectively, in agreement with previous results obtained with radioactive probes. The adaptation of fluorescence intensification and digital image processing (frame integration to enhance signal-to-noise ratio and linear contrast stretching) to microscopy makes it possible to detect very weak fluorescent spots on chromosomes. This system allows a high spatial resolution (less than 0.6 micron), even at very low fluorescence levels. The efficiency and the specificity of the hybridization and detection methodology give a direct and precise localization of the short single-copy sequences on human chromosomes.

Base Sequence↗
PubMed1989

Specificity of melphalan-induced rearrangements and their transmission through cell divisions.

The clastogenic effect of melphalan, an alkylating agent frequently used in chemotherapy, was investigated using chromosomes from human lymphocytes, two and three cell cycles after treatment in vitro. chromosome aberrations were much more frequent than chromatid type anomalies. Unbalanced rearrangements, i.e. deletions, dicentrics and complex rearrangements (in decreasing order of occurrence), were quite frequent and balanced rearrangements, such as reciprocal translocations and inversions, were quite rare. Deletions principally affected chromosomes 9, 5, 7 and 11. By comparison to the results obtained at first division after treatment, the relative frequencies of del(5) and del(20) increased with the number of cell divisions. Thus, these deletions were poorly eliminated by selection. This finding may be related to the fact that del(5) and del(20) are frequently observed in premalignant haemopathies.

Adult↗
PubMed1989

Synaptonemal complex study in some species of Gerbillidae without heterochromatin interposition.

Synaptonemal complexes were studied in Gerbillus campestris, Meriones libycus, M. shawi, M. crassus, and in two hybrids M. shawi x M. libycus (Gerbillidae, Rodentia). In both the pure species and hybrids, there was no pairing of X and Y chromosomes, as was previously observed in Psammomys obesus and other Gerbillidae species with gonosome-autosome translocations. A pair of autosomes was also located in proximity to the sex chromosomes in pachytene and showed unusual meiotic behavior with no, incomplete, or much delayed pairing. This chromosome pair, composed of late replicating heterochromatin, exists in most Gerbillidae species and is constant in number, but variable in size across the species. Both meiotic and mitotic characteristics indicate that this pair may correspond to a new type of chromosome which is different from B chromosomes. We do not know if there is a relationship between the presence of this chromosome and the unusual behavior of the sex chromosomes. In Gerbillidae species, the lack of pairing of both sex and heterochromatic chromosomes obviously does not prevent their correct meiotic segregation.

Animals↗
PubMed1989

The decrease of catalase or esterase D activity in patients with microdeletions of 11p or 13q does not increase their radiosensitivity.

Lymphocyte cultures from patients affected by retinoblastoma (Rb), with or without a microdeletion of chromosome 13, and Wilms tumor (WT), with a microdeletion of chromosome 11p where exposed to gamma-ray radiation during S and G2 phases. Chromatid and chromosome lesions were scored and compared to those observed in controls. No significant differences were detected, neither between patients and controls, nor between patients carrying or not a microdeletion. This lack of difference was unexpected since the genes for catalase and esterase D, also called S-formyl glutathione hydrolase, which are two detoxication enzymes, are deleted in case of microdeletion of 11p and 13q, respectively.

Acatalasia↗
PubMed1989

How are sticky chromosomes formed?

Blood lymphocytes in culture were irradiated by gamma-rays 3 h to 30 mn before harvesting. The various induced lesions were analysed, with a particular attention on sticky chromosomes, i.e. radial figures in which chromosomes are not obviously broken, but are linked by a tiny filament. Such anomalies are preferentially induced in mid to late G2-phase. They result from recombinations occurring at nonrandom chromosome regions: junction between hetero- and euchromatin, and telomeric regions. It is proposed that they are formed when double strand breaks are induced while intrachromatidic links have started to be formed in the course of chromosome condensation. If this interpretation is correct, the apparent lack of induced breakage of premitotic chromosomes is artifactual.

Cells, Cultured↗
PubMed1988

DNA content and genetic evolution of human colorectal adenocarcinoma. A study by flow cytometry and cytogenetic analysis.

We have conducted in parallel DNA flow cytometry (FCM) and cytogenetic (CG) analysis of a series of surgical specimens from 35 human colorectal adenocarcinomas. An excellent quantitative correlation was observed (r = 0.99) between modal peak values of FCM histograms and chromosome counts. This observation confirms that aneuploidy, as defined by FCM, accurately reflects the deviation from diploidy of the genomic DNA. FCM-derived DNA patterns have been analyzed in the context of the clonal chromosomal evolution determined by CG analysis. In the metaphases of a given tumor, even if karyotypes of different ploidy exist, the presence of identical marker chromosomes suggests a common origin for the multiple populations observed by FCM. Thus, heterogeneity in DNA content within a tumor, including the polyploidization step, would be indicative of genetic evolution.

Adenocarcinoma↗
PubMed1988

Jumping translocation of chromosome 14 in a skin squamous cell carcinoma from a xeroderma pigmentosum patient.

The cytogenetic study of a case of cutaneous squamous cell carcinoma developed in a child affected by xeroderma pigmentosum is described. In this paratetraploid tumor, virtually all mitoses had the following rearrangements: i(1q), i(1p), t(3q14q), del(9p), and der(19)t(8;19). In addition, there were several deletions of 1p and 1q. The del(9p) likely occurred as the first rearrangement. The distal segment of the short arm of chromosome #9 and the long arm of #19 and #22 were the most underrepresented and chromosome #6 the most overrepresented chromosome or chromosome segment. The most striking anomaly detected was a jumping translocation of chromosome #14, involved with chromosomes #1, #3, #5, #7, #9, #14, and #22. The breakage of chromosome #14 always occurred on the short arm.

Carcinoma, Squamous Cell↗
PubMed1988

Chromosome imbalance in endometrial adenocarcinoma.

The results of karyotypic analysis by R-banding after short-term culture of eight new cases of endometrial adenocarcinomas are presented and compared to previously published data. Among a total of 25 cases reported that had a diploid or near-diploid chromosome number, 72% contained a trisomy or tetrasomy 1q, often as the only abnormality. An excess of the long arm of chromosome 1 is, therefore, shown to be the predominant feature of endometrial adenocarcinoma. Trisomies 10, 2, 7, and 12 were, in decreasing order, the most frequently associated abnormalities, but trisomy 10, found in 40% of the cases, can also exist as the only imbalance. Because breakpoints in chromosome 1 are generally centromeric, a position effect with oncogene activation seems unlikely. It is suggested that the observed chromosome imbalances are secondary and are the result of the adaptation of the cancer cell to disturbed metabolic pathways.

Adenocarcinoma↗
PubMed1988

Loss of alleles on chromosome 18 and on the short arm of chromosome 17 in polyploid colorectal carcinomas.

The zygosity of 19 colorectal carcinomas (either near-diploid or polyploid) from patients known to be heterozygous for RFLPs located on chromosome 18 or on the short arm of chromosome 17 has been examined. In most cases, at least one allele was significantly under-represented. The reason for the absence of complete loss of heterozygosity was investigated for 5 polyploid tumors. It was shown that the diploid component which, in these tumors, is essentially composed of non-neoplastic cells, remains heterozygous as the polyploid component invariably loses heterozygosity. The results strongly suggest that many colorectal carcinomas originate from a single cell which had lost at least part of either chromosome 18 or of one short arm of chromosome 17, or both.

Adult↗
PubMed1988

Relevance of DNA ploidy as a measure of genetic deviation: a comparison of flow cytometry and cytogenetics in 25 cases of human breast cancer.

Twenty-five human breast cancers, surgically resected, were studied by cytogenetic analysis and DNA flow cytometry (FCM). The establishment of karyotypes showed that multiple cell populations probably were derived from a single ancestor clone, because common marker chromosomes always could be demonstrated. Differences of up to 30% were observed when the estimates of DNA content by the two methods were compared. A general tendency toward the acquisition of large marker chromosomes should be at the origin of this discordance, as the proportion of markers for each case correlated significantly with the magnitude of the difference. Parallel use of the two methods revealed the existence of tumors with DNA diploid FCM profiles and highly abnormal hypodiploid karyotypes (35-40 chromosomes), which may explain the limited value of DNA ploidy as an independent prognostic factor in breast cancer.

Adult↗
PubMed1988

Acquired chromosome rearrangements in human lymphocytes: effect of aging.

A prospective study of structural rearrangements occurring in normal lymphocytes was carried out. For each of two newborns and four young and two old adults, about 1000 metaphases from 72-h and 120 from 48-h cultures were studied. The frequency of rearrangements between bands 7p14, 7q35, 14q11.2 or 14q12 and 14qter, which is on the average about 0.003, is higher in newborns (0.0043) than in adults (0.0024). Conversely, the rearrangements involving other bands, which have a frequency of 0.025 on the average, are more frequent in old adults (f = 0.038) than in young adults (f = 0.025) and newborns (f = 0.013). The first type of rearrangement, which occurs in utero, may correspond to immunoglobulin and related gene rearrangements. The other rearrangements seem to accumulate progressively and may reflect exposure to mutagens. It is import to discriminate these two types of rearrangements when studying the effect of low doses of mutagens.

Adult↗
PubMed1988

Deletion proximal to DXS68 locus (L1 probe site) in a boy with Duchenne muscular dystrophy, glycerol kinase deficiency, and adrenal hypoplasia.

We report a case of a boy with Duchenne muscular dystrophy (DMD) associated with GK deficiency (GK), congenital adrenal hypoplasia (AHC), and mental retardation. Cytogenetic analysis of prometaphasic chromosomes revealed an interstitial chromosome deletion at Xp21.2 possibly extending to Xp21.1 or Xp21.3. His phenotypically normal mother was heterozygous for this deletion. DNA probe analysis on Southern blots showed that the deletion affected the following probe sites: 754, pERT 84, 21A, XJ2.3, pERT 87, JBir, and J66-H1, whereas L1, C7, and CX5.4 probes gave a normal signal. Pulse field gel electrophoresis after SfiI digestion did not show abnormal fragments with L1. These data are consistent with a deletion of about 4 megabases and indicate that the GK and AHC loci are proximal to L1 and distal to J66-H1.

Adrenal Insufficiency↗
PubMed1988

Effect of caffeine in Fanconi anemia. I. Restoration of a normal duration of G2 phase.

In Fanconi anemia (FA) cells the duration of the G2 phase of the cell cycle prolonged. Such a slowing of the G2 phase can be induced in normal cells by irradiation with gamma rays during S phase, which also further increases the duration of G2 in FA cells. The addition of caffeine during the last 7 h of culture shortens the G2 phase in both nonirradiated and irradiated FA cells. In nonirradiated normal cells it may have no effect or may increase G2 phase duration, but in irradiated normal reduces the slowing of G2 induced by the radiation. This suggests that FA cells recognize and repair preexisting DNA lesions during G2 phase and that caffeine inhibits this process. The principal anomaly in FA may be a deficient repair during S phase, as manifest in the prolonged postreplication repair period during G2 phase required to repair the larger number of lesions passing through S phase.

Anemia, Aplastic↗
PubMed1988

Transmission of radiation-induced rearrangements through cell divisions.

A BrdU incorporation technique associated with heat denaturation, acridine orange staining and UV irradiation, was applied to G0-irradiated lymphocyte cultures. This made it possible both to obtain an R-banding, and to estimate the number of divisions undergone by each cell in mitosis irradiation. Cell survival and slowing down of the cell cycle could be distinguished. The frequency of various types of rearrangements, and their association was studied at each cell division. It is shown that the loss of cells carrying chromosomal rearrangements is determined by several parameters such as the presence of dicentric or multicentric chromosomes and above all the association of several rearrangements in the same cell.

Cell Cycle↗
PubMed1988

Diagrammatic representation for chromosomal mutagenesis studies. IV. Radiation-induced rearrangements in Ateles sp. (Primate, Platyrhini).

In order to study the induction of rearrangements by gamma-rays in relation to chromosomal size and morphology, experiments were conducted in an Ateles, a species with a rather unusual karyotype among primates. It possesses some very large chromosomes, which tend to be too rarely affected, especially by intrachanges like inversions. Both their large size and their characteristic banding pattern suggest that this low involvement is not due to difficulty of analysis. This suggests very strongly that chromosomal involvement in rearrangements is not a function of size. The possible role of other factors involved in chromosomal rearrangements like chromosome position during interphase are discussed.

Animals↗