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J Couturier

Publications and source records attributed to J Couturier.

At least 55 records · Page 3Linked to original sources
PubMed1992

Partial trisomy 8q. Two case reports with maternal translocation and inverted insertion: phenotype analyses and reflections on the risk.

Partial trisomy 8qter-->q23 or q24.1 has been reported in 15 literature cases. We add two further case reports here. Patient 1 inherited the derivative (2) of a balanced maternal reciprocal translocation t(2;8)(qter;q2300) after 2:2 disjunction and adjacent-1 segregation, and is trisomic for the segment 8qter-->q2300. Patient 2 inherited a recombinant (8) of a balanced maternal inverted insertion inv ins(8)(q1300;q2300q24.2) and is trisomic for the segment 8q24.2-->q2300. The phenotype of both patients is described and compared to the spectrum of symptoms established from the 15 literature cases. This spectrum contains all features observed with a frequency of > = 50%. Patient 1 had 35% of the features of this spectrum; Patient 2 had 47%. The intrauterine survival probability of unbalanced offspring is assumed to be the same in both cases, as nearly the same segments are trisomic. The pedigrees indicate that the inversion carrier may have a reduced production probability of unbalanced gametes and therefore a reduced risk compared to the translocation carrier.

Abnormalities, Multiple↗
PubMed1992

[Injection of collagen in recurrent paralysis after thoracic surgery].

The author describes a new technique of treatment of recurrent laryngeal nerve paralysis by intra-cordal injection of collagen after thoracic surgery. After description of the collagen used and the technique of injection, the author presents the results. It is a new method, simple, efficient, well tolerated, giving patients a voice, and treating their swallowing troubles.

Collagen↗
PubMed1991

Integration of papillomavirus DNA near myc genes in genital carcinomas and its consequences for proto-oncogene expression.

DNA sequences of specific human papillomavirus (HPV) types are found integrated in the cell genome in most invasive genital carcinomas. We have determined the chromosomal localization of integrated HPV type 16 (HPV-16) or HPV-18 genomes in genital cancers by in situ hybridization experiments. In three cancers, HPV sequences were localized in chromosome band 8q24.1, in which the c-myc gene is mapped, and in one cancer HPV sequences were localized in chromosome band 2p24, which contains the N-myc gene. In three of the four cases, the proto-oncogene located near integrated viral sequences was found to be structurally altered and/or overexpressed. These data indicate that HPV genomes are preferentially integrated near myc genes in invasive genital cancers and support the hypothesis that integration plays a part in tumor progression via an activation of cellular oncogenes.

Blotting, Northern↗
PubMed1991

Karyotypic study of four gibbon forms provisionally considered as subspecies of Hylobates (Nomascus) concolor (Primates, Hylobatidae).

We report here a karyotypic study of 6 individuals of Hylobates concolor leucogenys, 2H, concolor siki, 3H, concolor gabriellae, 1 hybrid H, concolor leucogenys x H. concolor ski, 3 hybrid H. concolor gabriellae x H. concolor siki and 2 hybrid H. concolor hainanus x H. concolor leucogenys. Difficulties raised by the morphological identification of subspecies are discussed, and a new morphological characteristic for recognising female H. concolor gabriellae is described. Each of the 4 subspecies appears to be distinguishable on the basis of its karyotype: H. concolor leucogenys differs from H. concolor siki by a reciprocal translocation, from H. concolor hainanus by a pericentric inversion and from H. concolor gabriellae by the presence of both of these two rearrangements. However, these data do not allows us to identify a phylogenetic relationship between the subspecies because, with respect to the karyotypes, none occupies an ancestral position in comparison with the others.

Animals↗
PubMed1990

Human papillomavirus type 16 DNA is integrated into chromosome region 12q14-q15 in a cell line derived from a vulvar intraepithelial neoplasia.

The SK-v cell line, established from a precancerous lesion (a vulvar intraepithelial neoplasia), contains 10 to 20 copies of the human papillomavirus type 16 (HPV16) genome, and was previously shown to derive from a clone of cells present in the patient's lesions. By in situ hybridization the integrated HPV16 DNA sequences were localized to a single site in chromosome region 12q14-q15. The localization of viral sequences to a single nonrearranged chromosome 12 suggests that integration occurred at this site in the patient's premalignant lesions. The INT1 and GLI protooncogenes are located in this chromosomal region. No detectable modification of the structure and expression of these genes was observed by blot hybridization experiments.

Carcinoma in Situ↗
PubMed1990

Assessment of chromosome 22 anomalies in neurinomas by combined karyotype and RFLP analyses.

We report the cytogenetic study of 28 neurinomas; sixteen of them were also analysed using 11 polymorphic DNA markers for the loss of alleles of chromosome 22. Partial or total loss of chromosome 22 was found in nine cases. The results of the two approaches appear homogeneous, however, three tumors that yielded only cells with normal karyotypes demonstrated loss of constitutional heterozygosities. One of the tumors, which displayed an isodicentric or isopseudodicentric 22, was obtained in a patient with von Recklinghausen neurofibromatosis. It appears that loss of chromosome 22 is a characteristic of neurinomas whatever their context of occurrence.

Alleles↗
PubMed1990

The neuroepithelioma breakpoint on chromosome 22 is proximal to the meningioma locus.

The recurrent translocation breakpoint on chromosome 22 of neuroepithelioma has been localized between two probes, D22S1 and D22S15, by both in situ hybridization and somatic cell hybrids. These two probes have further been shown to be genetically linked at theta = 0.0 and a lod score of 5.3. The two probes were unaffected by a partial deletion of the chromosome 22 long arm of a meningioma, showing that the meningioma locus is distal to that of the neuroepithelioma.

Blotting, Southern↗
PubMed1990

Deletion of the pseudoautosomal region and lack of sex-chromosome pairing at pachytene in two infertile men carrying an X;Y translocation.

Two males with a 46,Y,der(X),t(X;Y)(p22.3;q11) complement were referred independently for evaluation of sterility with azoospermia. Both patients exhibited minimal symptomatology, characterized only by psychological disturbances. Study of X-chromosome breakpoints with pseudoautosomal probes 68B (DXYZ2 elements), 113D (locus DXYS15), and 19B (locus MIC2) indicated in both patients that at least 97% of the X pseudoautosomal sequences are lost. Hybridization with Xp22.3-specific probes DXS283, DXS284, and DXS31 shows that these loci are retained on the rearranged chromosome. Thus, the X-chromosome breakpoints are located close to the proximal boundary of the pseudoautosomal region, between MIC2 and DXS284.

Blotting, Southern↗
PubMed1989

Chromosomal aberrations induced by low-dose gamma-irradiation. Study of R-banded chromosomes of human lymphocytes.

The effect of low-dose (0-0.5 Gy) gamma-radiations was studied on R-banded chromosomes from lymphocytes of healthy donors of various ages. In cells from newborns, an increase of chromosome damage roughly proportional to the dose was found. In lymphocytes from young adults chromosomal aberrations were not detected at doses of 0.05 and 0.1 Gy, and in lymphocytes from old adults chromosomal aberrations were not detected at doses of 0.05 and 0.1 Gy, and in lymphocytes from old adults not even at 0.2 Gy. The difficulty in detecting aberrations in lymphocytes from adults is largely due to a considerable background of chromosomal anomalies which should be borne in mind in dosimetry studies. The rate of induction largely depends on the types of rearrangements. One-break terminal deletions are efficiently induced at 0.1 and 0.2 Gy and are the best indicators of exposure at these doses. At 0.5 Gy, the frequencies of 2-break lesions, i.e., dicentrics and reciprocal translocations, increase, whereas that of deletions decreases.

Chromosome Aberrations↗
PubMed1989

[Lethal polymalformative syndrome with 13q deletion secondary to a maternal X; 13 translocation].

The authors report the case of a newborn full term delivered by cesarean section for evolutive hydrocephalus, in the last month of pregnancy. This hydrocephalus was confirmed by echography after birth. This also having ambiguous genitalia and atresia ani, he died a few hours later. No evidence of infectious or toxic embryofetopathy was found out as an etiologic factor, but the karyotype of the baby showed a 13 q deletion and that of the mother a non reciprocal Xqter; 13q31.3 translocation. The study of inactivation of X indicated that the inactivated X chromosome in each cell was normal. On this occasion, the authors try to bring together the main points of "13q-syndrome" and discuss on the practical approach of antenatal diagnosis which they could propose to the couple.

Abnormalities, Multiple↗
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

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

Synaptonemal complexes in a subfertile man with a pericentric inversion in chromosome 21. Heterosynapsis without previous homosynapsis.

Analysis of surface-spread synaptonemal complexes of zygotene and pachytene spermatocytes was carried out on a human male carrier of a pericentric inversion of chromosome 21 ascertained after four miscarriages. The synaptic behavior of the bivalent, which could be unambiguously identified by its nonaligned kinetochores, was analyzed. All zygotene and pachytene spermatocytes had 22 linearly paired autosomal bivalents, with apparently normal synaptonemal complexes, and no evidence of a loop configuration in the 50 cells analyzed. According to the XY type (classification of Solari), the cells were distributed across zygotene and pachytene stages, not exclusively in the late pachytene to which adjustment is conventionally thought to be confined. It is suggested that inverted segments heterosynapse at early pachytene, without previous homosynapsis. It is expected that this meiotic process leads to failure of crossing-over, reduces the production of unbalanced gametes, and the risk of recombinant offspring, but can increase the incidence of aneuploidy as a result of nondisjunction during meiosis I (a frequent cause of pregnancy wastage).

Adult↗
PubMed1988

Inherited Xq duplication due to a zygotic translocation t(X;X)(q23;q27).

An Xq-duplication was found in a female child with multiple malformations. The family study revealed that her mother, who has a nearly normal phenotype, carries the same duplication. The karyotype of the grandmother shows the existence of a mosaicism: 46,X,del(X) (q23)/46,X,dup(X)(q27----q23). This mosaicism can be related to a translocation t(X;X)(q23;q27) during the first cell division of the zygote.

Adult↗