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C Duval

Publications and source records attributed to C Duval.

At least 19 recordsLinked to original sources
PubMed1995

Scavenger effect of vitamin E and derivatives on free radicals generated by photoirradiated pheomelanin.

The free radical scavenger properties of vitamin E (DL-alpha-tocopherol), a natural antioxidant, and derivatives were studied using an original in vitro method consisting of free radical production by photoirradiation of pheomelanin and direct detection of the free radicals by a physical, specific technique, electron spin resonance. Validation of this method has been realized using well-known biological free radical scavengers, superoxide dismutase and reduced glutathione. DL-alpha-Tocopherol, tocopheryl acetate, tocopheryl linoleate, and tocopheryl polyoxyethylene (POE) succinate induced a significant diminution of the free radical production. In order of efficiency, tocopheryl POE succinate was the best scavenger (37.6% inhibition at 0.25%) followed by tocopheryl linoleate (25.6% inhibition at 1%) and tocopheryl acetate (23.9% inhibition at 0.5%) and finally DL-alpha-tocopherol (16.2% inhibition at 0.05%). The results reported a decrease of the inhibitory effect for high concentrations of DL-alpha-tocopherol (0.1%) and tocopheryl acetate (1%), showing a tendency of this compound to act as a prooxidant. Used in optimal concentrations in cosmetologic or dermatologic formulations, Vitamin E and these derivatives should prevent or reduce the harmful activity of free radicals in the skin.

Animals↗
PubMed1995

Discordant malignant lymphoma synchronous or successive high-grade B lymphoma associated with Hodgkin's disease. A clinico pathologic and immunophenotypic study of 4 cases.

We report in 4 patients the rare association of Hodgkin's disease and high grade B malignant lymphoma. In 2 cases, both tumours were disclosed at the same time but in different tissues from the same region. In the 2 other patients, the second tumour was found 11 months and 12 months after the first respectively. In all cases Hodgkin's disease was of the nodular sclerosing type, the tumour cells expressing CD 30 and CD 15. The high grade lymphomas were of the polymorphic centroblastic (large non cleaved) type and expressed the B markers. One (case 4) was secondary to a follicular lymphoma. In 2 cases (2 and 4) the search for a latent EBV infection was negative in both tumours. In case 1, only the Reed-Sternberg cells were positive with both techniques. Such an association is different from so-called composite lymphomas, and can be called "discordant lymphoma". Different related conditions are discussed. This association is distinct from lymphomas or Hodgkin's disease complicating the treatment of Hodgkin's disease or malignant lymphomas.

Adult↗
PubMed1994

LAZ3 rearrangements in non-Hodgkin's lymphoma: correlation with histology, immunophenotype, karyotype, and clinical outcome in 217 patients.

We have recently shown that an evolutionary conserved gene LAZ3, encoding a zinc finger protein, is disrupted and overexpressed in some B-cell lymphomas (mainly with a large cell component) that show chromosomal rearrangements involving 3q27. Because the breakpoints involved in these rearrangements are focused in a narrow major translocation cluster (MTC) on chromosome 3, we used genomic probes from this region to study the molecular rearrangements of LAZ3 in a large series of patients (217) with non-Hodgkin's lymphoma (NHL). Southern blot analysis showed LAZ3 rearrangement in 43 patients (19.8%). Rearrangement was found in 11 of the 84 patients (13%) with follicular lymphoma but was most frequent in aggressive lymphoma (diffuse mixed, diffuse large cell, and large cell immunoblastic subtypes), in which 31 of the 114 patients (27%) were affected. The highest proportion of LAZ3 alteration was observed in B-cell aggressive lymphoma (26 of 71 cases, 37%). Eleven of the 32 patients with 3q27 chromosomal abnormality had no LAZ3 rearrangement, suggesting the possibility of LAZ3 involvement outside the MTC. On the other hand, 18 of the 39 patients with LAZ3 rearrangement and available cytogenetic results did not have visible chromosomal break at 3q27, suggesting that almost a half of the rearrangements are not detectable by cytogenetic methods. No statistical association could be found between LAZ3 status and initial features of the disease or clinical outcome in either follicular or aggressive lymphomas. We conclude that LAZ3 alteration is a relatively frequent event in B-cell lymphoma, especially in those of aggressive histology. It could be used as a genomic marker of the disease, and further studies are needed to clarify clinical implications of these alterations.

Blotting, Southern↗
PubMed1994

Expression of opioid peptides in cells and stroma of human breast cancer and adenofibromas.

The expression of beta-endorphin, Met-enkephalin and Leu-enkephalin was studied in 63 malignant and benign human breast tumors using immunohistochemical methods. Among invasive ductal carcinomas, 93% were positive for beta-endorphin, 87% for Leu-enkephalin and 90% for Met-enkephalin, in both the tumor stroma and the cell bodies. Enkephalin was predominant in cells, whereas endorphin was predominant in stroma. Nearly the same distribution was found in adenofibromas. In pericancerous normal tissue, neuropeptides were predominantly expressed in the stroma. Although the neuropeptide expression is not cancer-specific, it could be cancer-related, since the results suggest that the neuropeptide expression could reflect the host response to cancer cells and not only the cancer cell activity. The possibility of a direct action of the nervous system on stroma reaction and then on cancer cells is discussed.

Adenofibroma↗
PubMed1993

Adult onset Still's disease and pregnancy.

The interactions between pregnancy and adult onset Still's disease (AOSD) are unclear. Between 1983 and 1990, 5 pregnancies occurred in 4 women with AOSD. AOSD occurred at the 5th and 6th month of the 1st pregnancy in 2 patients; a 2nd pregnancy occurring in one of them was not associated with a flare. In the other 2 patients pregnancy occurred 36 and 44 months after the AOSD; during gestation only transient arthralgia were observed in both cases. Pregnancy seems to have no effect on AOSD, and conversely, in our experience, AOSD has no influence on pregnancy, fetal growth or infant health.

Adult↗
PubMed1992

Hyaluronan (hyaluronic acid) and hyaluronectin in the extracellular matrix of human breast carcinomas: comparison between invasive and non-invasive areas.

We performed quantitative determination of the distribution of hyaluronan (hyaluronic acid, HA) and the HA-binding protein, hyaluronectin (HN), 2 components of the extracellular matrix of tumor desmoplasia, within 71 human breast carcinomas. Results showed that HA and HN were more elevated in tumoral than in non-tumoral adjacent tissue, and that the peripheral invasive area of tumors contained increased levels of HA and HN as compared with the central non-invasive area (p less than 10(-3) and p less than 10(-5) respectively). HN and HA levels of 61 ductal carcinomas were related to the histological grade of tumors; no significant difference was found between grades for HA; HN was found to be significantly lower in grade III than in grade II tumors (p less than 0.01). HA and HN rates were correlated in grade I and grade II tumors and were not correlated in grade III. Mean percentage of HA saturation level by HN for whole tumors was found to be less than 4%, indicating that HA is essentially free of proteins and could be used as a target for cancer diagnosis or therapy.

Breast Neoplasms↗
PubMed1992

Toxic effects and detection of oxygen free radicals on cultured articular chondrocytes generated by menadione.

The aim of this work was to study the proliferation pathological perturbations of cultured chondrocytes in response to menadione, an oxygen free radicals producing drug. Rabbit articular chondrocytes in monolayer culture were treated with 10(-5) M, 1.5.10(-5) M and 2.10(-5) M of menadione during three days. A dose dependent decrease of the proliferative capacity was observed. Flow cytometry analysis revealed a perturbation of the cell cycle progression consisting in an accumulation of cells in the S and G2 + M phases. This growth perturbation was due to oxygen radicals production since a treatment with catalase suppressed these toxic effects. Furthermore, to identify oxygen derived radicals in the cellular suspension of cultures treated with menadione, we used a technique of spin-trapping coupled with electron spin resonance (ESR). The ESR signal corresponding to the DMPO hydroxyl radical adduct (DMPO-OH) has been detected. The spectra observation indicated the actual production of hydroxyl radical. However, superoxide anions have not been identified; this fact can be explained by the low reactivity of these anions with DMPO and by the decomposition of signal DMPO-OOH to DMPO-OH.

Animals↗
PubMed1991

Expression and post-transcriptional regulation of ornithine decarboxylase during early Xenopus development.

In this paper we show that large changes in ornithine decarboxylase (ODC) activity occurred during early Xenopus development. Following fertilization, this enzyme activity rises with a quantitatively correlated accumulation of putrescine and spermidine. This increase in ODC activity was associated with an increased translation of the maternal ODC mRNA, which was stable in the embryo and whose polyadenylation increased slightly between fertilization and the mid-blastula transition (MBT). ODC activity was stable in cycloheximide-treated embryos, indicating that before the MBT this enzyme was not degraded. After the MBT, ODC activity fell, but no decrease in this mRNA was observed. In gastrulae, ODC mRNA was both increased in amount and polyadenylated. The reduced ODC activity at this stage of development was not associated with a fall in ribosome loading of the mRNA. Treatment of post-MBT embryos with cycloheximide lead to an accentuation of the normally observed decrease in ODC activity. Expression of Xenopus ODC in mutant ODC-deficient Chinese hamster ovary cells (C 55.7 cells) showed that the Xenopus enzyme was rapidly degraded and can be regulated post-translationally by polyamines, indicating that the post-MBT fall in ODC activity could be caused by a change in protein turnover or by polyamine-mediated regulation.

Animals↗
PubMed1991

Cytogenetic studies in untreated Hodgkin's disease.

Very little data have been published on cytogenetic abnormalities in Hodgkin's disease (HD) and their correlation with clinicopathologic features are scanty. We have performed chromosomal analysis of lymph nodes from 60 previously untreated HD patients and obtained analyzable metaphases in 49 patients (82%). Chromosomal abnormalities were found in 33 patients (55%) but only 31 karyotypes could be, at least partially, described. Twenty-nine cases showed numerical abnormalities that involved all chromosomes with the exception of chromosomes 13 and Y, which were gained less frequently and lost more frequently than other chromosomes. Structural abnormalities were found in 30 cases, involving all chromosomes except Y. Chromosomal regions 12p11-13, 13p11-13, 3q26-28, 6q15-16, and 7q31-35 were rearranged in more than 20% of the analyzable cases. No correlation was found between cytogenetic findings and initial characteristics. When compared with diffuse B-cell lymphomas, defects in regions 2p25 (P less than .01), 12p11-13 (P less than .01), 13p11-13 (P less than .01), 14p11 (P less than .01), 15p11-13 (P less than .02), and 20q12-13 (P less than .05) were more frequent in HD. When compared with T-cell lymphomas, only defects in regions 12p12-13 (P less than .01) and 13p11-13 (P less than .01) were more frequent in HD. Failure to obtain analyzable metaphases was correlated with stage IV of the disease (P less than .05) and with a poor survival (P less than .01), but cytogenetic results showed no other correlation with clinical outcome. We conclude that molecular studies in HD should be focused on the short arms of chromosomes 12 and 13. Determination of the clinical significance of cytogenetic findings will require a larger number of patients and a longer follow-up period.

Adolescent↗
PubMed1991

[Infectious spondylodiscitis after a cure for genital prolapse. 5 cases].

Bacterial osteitis of the discs and the vertebrae is rare after fixing the uterus to the promontary of the sacrum. Only 30 cases have been reported in the literature. Twelve cases were found in a Rheumatology Unit over a period of 12 years from 1975-1987. The initial symptoms of septic osteitis were low back pain or sciatica, and fever. They were confirmed by radiological evidence. Bacteriological diagnosis was obtained in every case by fine needle aspiration of the disco-vertebral space retrieving staphylococci or gram-negative bacilli. The same agent was found in blood cultures in four or five cases. Potentiating pathogenic factors include urinary tract infections, prosthetic material, and surgical errors.

Adult↗
PubMed1990

Serum hyaluronan (hyaluronic acid) in breast cancer patients.

Eighty-three women with breast cancer (57 with systemic metastasis, 26 without) were investigated for serum hyaluronan (HA) and compared to 50 patients with benign diseases of the breast. Hyaluronan was significantly increased in sera of metastatic patients compared to sera of non-metastatic patients (p less than 0.0001) and also in sera of non-metastatic patients when compared to control sera (p less than 0.01). The difference was not related to the number of metastatic sites involved. Three months after starting cytotoxic chemotherapy in metastatic patients, lower HA concentrations were observed in patients responding to chemotherapy. The initial level of serum HA had no predictive value concerning response to chemotherapy.

Biomarkers, Tumor↗
PubMed1990

Stability of maternal mRNA in Xenopus embryos: role of transcription and translation.

The first 12 cell divisions of Xenopus laevis embryos do not require gene transcription. This means that the regulation of gene expression during this period is controlled at post transcriptional levels and makes Xenopus early development a potentially interesting biological system with which to study the mechanisms involved. We describe here the stability characteristics of several maternal Xenopus mRNAs which are deadenylated soon after fertilisation (J. Paris and M. Philippe, Dev. Biol., in press). We show that these mRNAs were only degraded in the embryo after the midblastula transition (MBT), when gene transcription was initiated. The kinetics with which the deadenylated maternal mRNAs decreased in the post-MBT embryos showed sequence specificity. The degradation of these mRNAs after the MBT was inhibited by cycloheximide but was not affected by dactinomycin. Therefore, the destabilization of these mRNAs does not appear to be initiated by new embryonic gene transcripts. Sequence comparisons of the 3' untranslated region of these mRNAs identified several motifs which may be involved in the posttranscriptional control of these gene products.

Animals↗