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N Ayraud

Publications and source records attributed to N Ayraud.

At least 19 recordsLinked to original sources
PubMed2000

Characterization of centromere alterations in liposarcomas.

Supernumerary ring and large marker chromosomes are a characteristic of atypical lipomas and well-differentiated liposarcomas (ALP-WDLPS) and are composed of amplified 12q14-15 sequences in association with variable segments from other chromosomes. Although stably transmitted, these chromosomes contain centromeric alterations, showing no detectable alpha-satellite sequences. We performed C-banding, fluorescence in situ hybridization, and immunostaining with anti-centromere antibodies in 8 cases of liposarcomas with supernumerary rings and large markers, including 5 ALP-WDLPS and 3 dedifferentiated-LPS and high-grade LPS. Our results with alpha-satellite probes and anti-CENPB antibodies confirm the lack of detectable alpha-satellite sequences in the five ALP-WDLPS supernumerary chromosomes, whereas centromeric activity was proved by the detection of kinetochores by using anti-CENPC antibodies. In contrast, the high grade and dedifferentiated liposarcomas showed a different pattern. In 2 cases, amplified chromosome 12 sequences, including amplification of alpha-satellite 12 sequences in 1 case, were present on chromosomes with typical centromeres. In another case, the rings were similar to WDLPS-ALP rings, but a large marker contained a chromosome 5 centromere and amplified alpha-satellite sequences from chromosome 8. ALP-WDLPS is the first example of a tumor class for which the presence of stable analphoid chromosomes is a constant and specific abnormality. Formation of newly derived centromeres, so-called neocentromeres, could be an original and effective way to maintain a selective advantage in neoplastic cells by conferring stability to the supernumerary chromosomes of ALP-WDLPS. The activation of normally non-centromeric sequences might be obtained by an epigenetic mechanism due to the peculiar chromatin conformation of these highly complex chromosomes.

Blotting, Southern↗
PubMed1996

Another case of t(17;22)(q22;q13) in an infantile dermatofibrosarcoma protuberans.

We have identified a new dermatofibrosarcoma protuberans (DP) case with a t(17;22) (q22;q13) occurring in a child. The translocation was substantiated by the presence of one or two copies of the sole der(22)t(17;22). This rearrangement added to two normal chromosomes 17 and one or two chromosomes 22, resulted in trisomy 22cen-q13 and trisomy (or tetrasomy) 17q22-25. This observation confirms the specificity of the association of DP with the t(17;22) found together with extra copies of the der(22)t(17;22). It also points out a possible prevalence of translocation rather than rings in DP of the childhood disease.

Antigens, CD34↗
PubMed1996

Fluorescence in situ hybridization analysis of t(3; 12)(q26; p13): a recurring chromosomal abnormality involving the TEL gene (ETV6) in myelodysplastic syndromes.

We have identified a new recurrent reciprocal translocation between chromosome 3 and 12 with breakpoints at bands 3q26 and 12p13, t(3;12)(q26;p13) in the malignant cells from five patients with acute transformation of myelodysplastic syndrome or blast crisis of chronic myelogenous leukemia. t(3;12)(q26;p13) appears as a rare but nonrandom event present in various myeloid leukemia subtypes, which is frequently associated with dysplasia of megakaryocytes, multilineage involvement, short duration of any blastic phase, and a very poor prognosis. Here, we report the molecular cytogenetic analysis of the t(3;12). Fluorescence in situ hybridization results indicate that the 3q26 breakpoints are quite heterogeneous and occur 5' of MDS1, 3' of EVI1, or between MDS1 and EVI1. Our results are very similar to those observed in other 3q26 rearrangements in which breakpoints were shown to occur over considerable distances 5' and 3' of EVI1. Fluorescence in situ hybridization investigations proved that, in three myelodysplastic syndrome cases with t(3;12)(q26;p13), the 12p 13 breakpoint occurred within the TEL gene.

Adult↗
PubMed1996

Translocation, t(17;22)(q22;q13), in dermatofibrosarcoma protuberans: a new tumor-associated chromosome rearrangement.

A translocation, t(17;22)(q22;q13), was identified in two cases of dermatofibrosarcoma protuberans (DP). They bring to four the number of DP cases characterized by an identical t(17;22)(q22;q13), which can be considered as a new tumor-associated chromosome rearrangement. To date, this translocation has been found only in DP and its juvenile form, giant-cell fibroblastoma. This finding has two major consequences. First, it casts light on the development and significance in DP of ring chromosomes which consistently harbor sequences derived from chromosomes 17 and 22. Second, the identification of this new chromosome marker, and eventually of the underlying molecular rearrangement, should help to classify DP, a soft-tissue tumor of still uncertain cell origin. In addition, it could be used to differentiate DP from truly benign or malignant entities, in order that this tumor of intermediate malignancy could be adequately managed.

Adolescent↗
PubMed1995

Rearrangement of proximal 11q13 band in a CMML in acute transformation.

Fluorescence in situ hybridization (FISH) was performed on bone marrow cells thought to contain a t(7;11)(p22;q13) from a patient with chronic myelomonocytic leukemia in transformation. FISH analysis using a panel of 10 probes previously mapped to 11q13 revealed a cytogenetically undetected complex rearrangement that involved chromosomes 7 and 11 as well as a chromosome 3 at band p24. Two distinct translocation breakpoints, both proximal to the BCL1 locus, were found in chromosome 11 that perforce separate it into three subregions. The two breakpoints appear distinct from the two previously described ones which involved the FAU and GSTP1 genes. Our observations add to the involvement of proximal 11q13 in myeloid malignancies.

Acute Disease↗
PubMed1994

Supernumerary ring chromosomes containing chromosome 17 sequences. A specific feature of dermatofibrosarcoma protuberans?

Mystery surrounds the mechanisms by which the uncommon cutaneous tumor dermatofibrosarcoma protuberans (DP) arises and progresses. A clue may be at hand in the form of extra abnormal chromosomes (one of three ring chromosomes per case with or without other chromosome abnormalities) seen in some 10 cases, including five cases in our experience. The specificity of the rings to DP would be enhanced if the rings were found to contain a contribution from a constant chromosome. We here report fluorescence in situ hybridization (FISH) results bearing on the chromosomal content of DP rings, together with clinical, pathologic, and cytogenetic documentation of our first two cases, which were briefly reported earlier, and three new DP cases. To dissect a translocation (in our 2nd case), we probed by FISH and discovered chromosome 17 sequences in the rings in all five DP cases. Nonfluorescent bands were seen on some rings painted with a whole chromosome 17 probe, indicating the presence in these rings of foreign chromosome sequences. The complexity of the rings was underscored by the detection in only one case of chromosome 17 centromeric sequences. The situation in DP seems to have parallels to that in well-differentiated liposarcoma, another tumor of intermediate malignancy with extra abnormal marker chromosome containing contributions from a constant chromosome and variable donors. In DP the supernumerary rings are clearly specific and significant.

Adult↗
PubMed1994

Recurrent cytogenetic abnormalities observed in complete remission of acute myeloid leukemia do not necessarily mark preleukemic cells.

We have undertaken the cytogenetic monitoring of 39 adult patients treated for de novo acute myeloid leukemia (AML) by intensive chemotherapy. We describe this monitoring in seven patients in continuous complete clinical and morphologic remission (CR) of AML. Although in CR, these patients exhibit the emergence of cytogenetically abnormal clones. Abnormalities observed include monosomy 7, del(20)(q11), partial trisomy 1q, and 6p12-22 rearrangements. They correspond to well-known chromosomal rearrangements commonly found in myelodysplasia (MDS), and myeloproliferative syndromes (MPS), as well as AML. Present as the sole detected chromosomal change, they preceded by months the onset of overt leukemia or MDS. In some cases, the abnormal clone showed a proliferative advantage (some patients exhibited up to 100% of abnormal bone marrow metaphases in subsequent analyses). AML relapse, when it occurred, was associated with a different chromosomal modification. Altogether the question arises, whether the abnormalities pointed out in our study (monosomy 7, del(20)(q11), partial trisomy for the long arm of chromosome 1 (q21qter), 6p12-22 rearrangements), and seen after chemotherapy, mark preleukemic cells or not, and whether they participate indirectly, or not at all in the leukemic process.

Adult↗
PubMed1991

Dynamics of human sperm acrosome reaction: relation with in vitro fertilization.

OBJECTIVE: Acrosomal status has been studied on human sperm prepared for in vitro fertilization (IVF) and related to the rate of fertilization. DESIGN AND PATIENTS: A group of 41 men with normal classical semen parameters, included in the IVF program of University of Nice for feminine tubal obstruction (n = 37) or unexplained infertility (n = 4), were evaluated in a prospective study and compared with a control group of 10 fertile donors. MAIN OUTCOME MEASURES: Evaluation of acrosome status (spontaneous and A23187-induced acrosome loss) after 6 hours incubation in Ménézo's B2 medium was made by flow cytometry on suspended cells with a new immunofluorescence test recently reported by the authors based on a monoclonal antibody GB24. RESULTS: Spontaneous acrosome loss remained low even after 6 hours capacitation (mean + 1 SD, 6.5% + 4.9%). Response to A23187 increased with the duration of preincubation with a marked response after 6 hours (29.5% + 8.9%). Low spontaneous acrosome loss (less than mean + 1 SD) and high response to A23187 (greater than mean - 1 SD) were observed in 25 out of 26 cases of group A with a high fertilization rate (greater than 50% fertilized oocytes). A high level of spontaneous acrosome loss and/or a lack of response to A23187 was observed in 2 of 7 cases of group B (fertilization rate less than 50%) and 6 of 8 cases of group C (unexplained unsuccessful fertilization). CONCLUSION: Impaired acrosomal status can be associated with unexplained unsuccessful fertilization.

Acrosome↗
PubMed1989

[Prenatal diagnosis of a translocation (X;Y) and genetic counseling].

A cytogenetic prenatal diagnosis due to maternal age led us to find a male fetus with a (X;Y) translocation. This translocation is found in the mother, who presents no phenotypic abnormalities or mental retardation. The 22 cases described in the literature indicate that among male carriers of an (X;Y) translocation, half the cases present mental retardation and 2/3 phenotypic anomalies. These findings led us to give a genetic counselling of therapeutic abortion. Post mortem histological examination revealed no morphodysplasia.

Abortion, Therapeutic↗
PubMed1985

Variant translocation t(8;21;15) in an acute myeloblastic leukemia with phenotypic differential evolution.

A new case of a variant form of the translocation (8;21) in an AML-M2, including in addition involvement of chromosome #15 is reported. The selection of two abnormal lines, probably resulting from two successive rearrangements of the (8;15) translocated segment, is observed. It is suggested that these rearrangements change the cellular morphology and seem to play a part similar to additional autosomal abnormalities in the course of the disease, such as those found in CML.

Aged↗
PubMed1985

HLA in families with Down's syndrome children.

Thirty couples having a DS child were typed for HLA-A and B antigens and compared to twenty control families and 176 blood donors. Although differences in frequency of B antigens exist between DS families and controls, they are not significant after correction for the number of antigens tested. No excessive HLA sharing was found in DS parents contrarily to two previous studies (Mattironi et al. 1981, Aymé et al. 1983).

Adult↗
PubMed1984

Triploidy with cyclopia and identical HLA alleles in the parents.

A 22-week pregnancy was terminated after discovery of serious echographic abnormalities. Fetal examination showed cyclopia, sacral meningocele, and syndactyly. The karyotype was 69,XXX. The parents had identical HLA alleles A1, A2, and Bw21. The mechanism of the triploidy was determined by chromosome marker analysis to be digyny. The association of triploidy with holoprosencephaly and the parents' identical immunological status are discussed.

Abnormalities, Multiple↗
PubMed1983

Distribution of neutral maltase activity in mononuclear cells from different human lymphoid organs.

Neutral maltase activity has been determined in purified monocytes, T and B lymphocytes from human peripheral blood and major lymphoid organs. In peripheral blood as in all lymphoid organs studied, neutral maltase activity was found to be significantly higher in monocytes than in B lymphocytes. Neutral maltase activity was never detected in T lymphocytes whatever the methods used for their purification. Furthermore, in each case studied, B lymphocyte fractions represented all the activities measured in unseparated lymphocytes. Neutral maltase thus appears to be the first enzymatic marker useful for the recognition and characterisation of B lymphocytes.

B-Lymphocytes↗