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Kressmann S, Morel F, Harlé V, Kasztelan S. Recent developments in fixed-bed catalytic residue upgrading. Catal Today 1998. [DOI: 10.1016/s0920-5861(98)00149-7] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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152
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Morel F, Mercier S, Roux C, Elmrini T, Clavequin MC, Bresson JL. Interindividual variations in the disomy frequencies of human spermatozoa and their correlation with nuclear maturity as evaluated by aniline blue staining. Fertil Steril 1998; 69:1122-7. [PMID: 9627303 DOI: 10.1016/s0015-0282(98)00058-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To evaluate the importance of interindividual variations in the disomy frequencies of human sperm and their possible correlation with the principal semen parameters. DESIGN Prospective randomized analysis of sperm nuclei by fluorescence in situ hybridization and analysis of semen parameters. SETTING University-based laboratory for reproductive biology. PATIENT(S) Fifty-seven human ejaculates selected at random from a population of men undergoing semen analysis. INTERVENTION(S) Semen specimens were analyzed, and sperm samples were prepared for fluorescence in situ hybridization. MAIN OUTCOME MEASURE(S) Semen parameters, including necrozoospermia, global motility, sperm concentration, multiple abnormalities index, and teratozoospermia were evaluated, aniline blue staining was completed, and disomy frequencies for chromosomes 8, 15, 18, X, and Y were determined using fluorescence in situ hybridization. RESULT(S) Noticeable differences in disomy frequencies between individuals were observed, and these frequencies were correlated with the degree of nuclear maturity. CONCLUSION(S) We hypothesize that the positive correlation can be explained by an abnormality of chromosomal segregation at the time of meiosis that would cause disturbances during the transition of nucleoprotein or by one or several premeiotic abnormalities of chromatin that would perturb both the meiotic process and the construction of definitive proteins.
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153
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Agarwal M, Austin TW, Morel F, Chen J, Böhnlein E, Plavec I. Scaffold attachment region-mediated enhancement of retroviral vector expression in primary T cells. J Virol 1998; 72:3720-8. [PMID: 9557654 PMCID: PMC109594 DOI: 10.1128/jvi.72.5.3720-3728.1998] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/1997] [Accepted: 01/29/1998] [Indexed: 02/07/2023] Open
Abstract
We have studied retroviral transgene expression in primary human lymphocytes. Our data demonstrate that transgene expression is high in activated primary CD4+ T cells but significantly decreased in mitotically quiescent cells. Incorporation of a DNA fragment from the scaffold attachment region (SAR) of the human beta interferon gene into the vector improved transgene expression, particularly in quiescent cells. The SAR element functioned in an orientation-dependent manner and enhanced expression of Moloney murine leukemia virus- and murine embryonic stem cell-based vectors. Clonal analysis of transduced T cells showed that the SAR sequence did not confer position-independent expression on a transgene but rather prevented the decrease of expression when cells became quiescent. The SAR sequence also enhanced transgene expression in T cells generated from retrovirally transduced CD34-enriched hematopoietic progenitor-stem cells in a SCID-hu thymus-liver mouse model. We have used the SAR-containing retroviral vector to express the RevM10 gene, a trans-dominant mutant of the human immunodeficiency virus type 1 (HIV-1) Rev gene. Compared to a standard retroviral vector, the SAR-containing vector was up to 2 orders of magnitude more efficient in inhibiting replication of the HIV-1 virus in infected CD4+ peripheral blood lymphocyte populations in vitro. This is the first demonstration that SAR elements can be used to improve retroviral vector expression in human primary T cells.
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154
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Petit N, Touraille S, Debise R, Morel F, Renoux M, Lécher P, Alziari S. Developmental changes in heteroplasmy level and mitochondrial gene expression in a Drosophila subobscura mitochondrial deletion mutant. Curr Genet 1998; 33:330-9. [PMID: 9618583 DOI: 10.1007/s002940050344] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Eighty percent of DNA molecules are deleted in the mitochondrial population of an adult mutant strain of D. subobscura. Both intact and deleted genomes are autonomous monomers. The heteroplasmy level, which is lower in germ tissue, increases from the oocytes (60%) to the third larval instar (83%), and is then maintained throughout the life of the fly. The mtDNA/nuclear DNA ratio is on average two-times greater in the heteroplasmic strain than in the wild-type strain, irrespective of the stage, but the cellular content of mitochondria is elevated only in the embryos and pupae of the mutant strain. The steady state concentrations (SSCs) of the transcripts affected by the deletion are greatly reduced at the larval and adult stages, and less so at the pupal stage of the mutant strain compared with the wild-type. The SSCs of these transcripts are identical in the two strains at the embryonic stage. The fusion transcript, indicating that the deleted genome is expressed, was detected at all stages. The mechanisms involved in the changes in the heteroplasmy level during the course of development and in its maintenance from the third larval instar onwards are discussed.
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155
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Morel F, Galy A, Chen B, Szilvassy SJ. Equal distribution of competitive long-term repopulating stem cells in the CD34+ and CD34- fractions of Thy-1lowLin-/lowSca-1+ bone marrow cells. Exp Hematol 1998; 26:440-8. [PMID: 9590662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
CD34 antigen is present on most, if not all, human hematopoietic stem cells (HSCs). Consistent with this pattern of expression, we recently reported that primitive murine HSCs defined as competitive long-term repopulating units (CRUs) are highly enriched among CD34+ bone marrow (BM) cells (one CRU/2500 cells). However, in agreement with one recent report that some murine HSCs do not express CD34 (Science 273:242), we observed that 15% of phenotypically defined Thy-1lowLin-/lowSca-1+ (TLS) stem cells were CD34- by fluorescence-activated cell sorting. To examine further the nature of CD34 expression on murine hematopoietic cells, we separated TLS cells into CD34+ (0.022% of BM cells) and CD34- (0.005% of BM cells) fractions, confirmed their phenotype by reverse transcriptase-polymerase chain reaction analysis of CD34 transcripts, and evaluated them in a variety of in vitro and in vivo assays. The CD34+ TLS population contained most (93-95%) of the day 12 spleen colony-forming units (CFU-S) and in vitro colony-forming cells (CFCs). Cobblestone area-forming cells (CAFCs) able to proliferate on a murine bone marrow stromal cell line (SyS-1) represented one of every 5 CD34+ TLS and one of every 31 CD34 TLS cells. When lethally irradiated mice were injected with 100 CD34+ TLS cells, all animals survived and began to recover circulating leukocytes, platelets, and erythrocytes by 15 days. In contrast, only 40% of mice injected with 100 CD34- TLS cells were radioprotected, and hematopoietic reconstitution in surviving mice was not apparent until 21 days. The frequency of CRUs in CD34+ and CD34 TLS cells was determined by injecting limiting numbers of cells into lethally irradiated Ly-5 congenic hosts together with 10(5) "compromised" BM cells to provide radioprotection. CRUs able to regenerate and maintain lymphoid and myeloid cells for at least 6 months in primary and 5 months in secondary hosts represented one of every 156 CD34+ TLS and one of every 35 CD34- TLS cells. However, when normalized for the proportion of TLS cells that were CD34+ or CD34-, it was determined that the recovery of CRU among CD34+ and CD34- TLS cells was equivalent (46% and 54%, respectively). These data are consistent with the previous description of repopulating HSCs among CD34-c-kit+Sca-1+Lin- cells (Science 273:242, 1996) and provide additional evidence that TLS cells are functionally heterogeneous and can be further fractionated on the basis of CD34 expression. Overall, approximately 95% of CFCs, CFU-S, and CAFCs in the TLS population were found to be CD34+, whereas more primitive CRU were distributed equally among CD34+ and CD34 TLS cells. These results should enable better characterization of the most primitive stem cells in murine BM.
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156
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Mercier S, Morel F, Fellman F, Roux C, Bresson JL. Molecular analysis of the chromosomal equipment in spermatozoa of a 46, XY, t(7;8) (q11.21;cen) carrier by using fluorescence in situ hybridization. Hum Genet 1998; 102:446-51. [PMID: 9600242 DOI: 10.1007/s004390050719] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The meiotic segregation of a balanced reciprocal translocation (7;8) (q11.21;cen) was analysed by interphase fluorescence in situ hybridization (FISH) on carrier spermatozoa. A dual interphase FISH technique was applied to 34,527 decondensed sperm heads with chromosome-7- and chromosome-8-specific alpha-satellite probes. Analysis with such probes was possible according to the cytogenetic characteristics of these translocation breakpoints, which implied a centromeric breakpoint. The majority of the analysed nuclei (56.70%) showed normal (30.40%) or balanced (26.30%) chromosomal equipment resulting from alternate segregation during meiosis. A total of 14,935 spermatozoa (43.26%) was unbalanced with a predominance of gametes resulting from adjacent-I (25.10%) or adjacent-II (11.10%) segregation; such gametes could produce partial mono- or trisomies at term. The frequency of analysed cells resulting from a 3:1 segregation, which could induce complete mono- and trisomies at term, was 7.06%; 0.04% of scored cells were diploid. The same dual-FISH technique was carried out either with chromosome-15- and chromosome-18-specific probes or with gonosome-specific probes, in order to detect a possible interchromosomal effect. A significant increase of disomic 18 spermatozoa was observed in the carrier. Such studies are not yet frequent. Multicolour-FISH seems a rapid and accurate tool for direct analyses of spermatogenetic segregation mechanisms in a carrier of balanced chromosomal abnormalities and provides interesting information for characterizing the possible risks for the offspring.
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MESH Headings
- Adult
- Centromere/genetics
- Chromosome Banding
- Chromosomes, Human, Pair 15/genetics
- Chromosomes, Human, Pair 18/genetics
- Chromosomes, Human, Pair 7/genetics
- Chromosomes, Human, Pair 8/genetics
- Heterozygote
- Humans
- In Situ Hybridization, Fluorescence
- Male
- Meiosis/genetics
- Spermatozoa
- Translocation, Genetic/genetics
- X Chromosome/genetics
- Y Chromosome/genetics
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Batot G, Paclet MH, Doussière J, Vergnaud S, Martel C, Vignais PV, Morel F. Biochemical and immunochemical properties of B lymphocyte cytochrome b558. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1406:188-202. [PMID: 9573361 DOI: 10.1016/s0925-4439(98)00004-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Like neutrophils, Epstein-Barr virus (EBV)-immortalized B lymphocytes express all constituents of the NADPH oxidase complex necessary to generate superoxide anion O2-. The NADPH oxidase activity in EBV-B lymphocytes is only 5% of that measured in neutrophils upon PMA stimulation. Cytochrome b558 is the sole redox membrane component of NADPH oxidase; it is the protein core around which cytosolic factors assemble in order to mediate oxidase activity. In the present study, we have compared the structural and functional properties of cytochrome b558 from EBV-B lymphocytes and neutrophils. Cytochrome b558 from EBV-B lymphocyte plasma membrane, like that from neutrophils, is characterized by a heterodimeric structure with a highly glycosylated beta subunit, known as gp91-phox. While the amount of cytochrome b558 recovered after purification from EBV-B lymphocytes (approximately 0.24 nmol from 1010 cells) was low compared to that recovered from neutrophils (approximately 10 nmol), the biochemical properties of purified cytochrome b558 from both EBV-B lymphocytes and neutrophils were quite similar with respect to their differential spectra, redox potential, and FAD binding site. Once cytochrome b558 was extracted from the EBV-B lymphocyte membrane, it was able to mediate, in a reconstituted system of O2- production the same oxidase turnover as that found for cytochrome b558 extracted from neutrophils. A comparison between membrane bound and soluble cytochrome b558 suggested that the weak oxidase activity measured in intact EBV-B cells might be the result not only of the small amount of expressed cytochrome b558, but also of a defect of the activation process in lymphocyte membrane.
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158
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Zaoui P, Barro C, Maynard C, Descotes JL, Maurizi-Balzan J, Cordonnier DJ, Morel F. Inter-regulated balance between gelatinases and tissue inhibitor (TIMP-1) in isolated human glomeruli. Ren Fail 1998; 20:201-9. [PMID: 9574444 DOI: 10.3109/08860229809045103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Leukocyte infiltration inside glomeruli necessitates basement membrane collagen i.v. breakdown and leads to mesangiolysis, cell proliferation and extracellular matrix synthesis during the repair process as observed in the course of acute glomerulonephritis, vasculitis and acute graft rejection. Two matrix metalloproteinases, MMP-2 and MMP-9 gelatinases, are expressed and co-secreted in balance with the tissue inhibitor of metalloproteinases-1 (TIMP-1) by activated neutrophils as well as by glomerular cells and are aimed to control basement membrane collage i.v. deposition. Using a conventional double mesh sieving method, pure populations of glomeruli were isolated from fresh human cortex specimen and maintained in short-term cultures. ELISA, zymography and immunoblotting of conditioned serum-free media revealed glomerular MMP-2, MMP-9 and TIMP-1 secretion and activity while reverse transcription-polymerase chain reaction amplification of cellular RNA demonstrated glomerular transcripts coding for these enzymes and their inhibitor. When purified neutrophils were allowed to adhere onto Transwell apparatus in contact with glomerular suspensions, neutrophil 92 kDa gelatinase seemed apparently inhibited mainly because the production of TIMP-1 was enhanced on both sides of the insert. Glomerular 72 kDa and 92 kDa gelatinases were activated shortly (1 to 6 h) after neutrophils had interacted with glomeruli and furthermore upon activation by inflammatory or vasoactive mediators such as phorbol. Decreased neutrophil MMP-9 activity together with reduced MMP-9 mRNA levels and protracted TIMP-1 transcription and secretion during cell-cell interaction could participate to cell detachment from degraded basement membranes and to increased collagen i.v. deposition leading to glomerulosclerosis after initial glomerular injury by inflammatory cells.
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159
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Galy A, Morel F, Hill B, Chen BP. Hematopoietic progenitor cells of lymphocytes and dendritic cells. J Immunother 1998; 21:132-41. [PMID: 9551365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Lymphocytes and dendritic cells (DCs) are critical for immune responses, yet how they develop from pluripotent hematopoietic stem cells is poorly defined. In humans and mice, it is possible to isolate phenotypically defined subsets of bone marrow (BM) cells that represent intermediate progenitors without long-term repopulating characteristics but with specific lineage differentiation properties. For instance, murine BM CD34+ CD45RA+ cells are progenitors for B and T lymphocytes with no in vivo repopulation activity. In human BM, a small subset (5%) of cells having the phenotype CD34+ Lin- CD10+ CD45RA+ CD38+ Thy-1- c-kit- represents a new class of hematopoietic progenitor cells that gives rise to lymphocytes [T, B, and natural killer (NK) cells] and to DCs but does not produce myeloid or erythroid cells. The identification of such progenitor cells provides the opportunity to define the differentiation and growth requirements for the production of lymphocytes and DCs. Genes involved in lineage specification can also be studied. Altogether, these studies have fundamental implications for understanding the biology of pivotal lineages of immune cells. This understanding could be used to treat a variety of immunodeficiencies and to design novel immunotherapies particularly in the context of hematopoietic cell transplantation.
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160
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Barro CD, Romanet JP, Fdili A, Guillot M, Morel F. Gelatinase concentration in tears of corneal-grafted patients. Curr Eye Res 1998; 17:174-82. [PMID: 9523096 DOI: 10.1076/ceyr.17.2.174.5602] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
PURPOSE Gelatinolytic enzymes, which degrade type IV basement membrane collagen, have been shown to be expressed by corneal cells, either constitutively (gelatinase A or MMP-2) or after induction (gelatinase B or MMP-9). Our aim was to determine whether an enhanced MMP-9 and eventually MMP-2 concentration in tears could be evidenced in the case of corneal-graft failure. METHODS The amount of MMP-2 and MMP-9 gelatinolytic enzymes was measured by quantitative zymography in tears of twenty-one controls (84 samplings) and in tears of twenty-three corneal-grafted patients in a one-year post-graft follow-up study. RESULTS The mean MMP-2 values in controls were of 8.4 (+/-7.3) pg/10 micrograms protein and the mean MMP-9 values in controls were of 73 (+/-76) pg/10 micrograms protein. No active gelatinase form was detected in any of controls, but in all cases of corneal graft failure, the active forms of both enzymes were present, and enzyme concentrations were higher than control values. All patients had significantly higher MMP-9 values than controls at each sampling time (p < 0.0001). The "corneal-graft failure" patient group had statistically significant higher MMP-9 concentrations in tears than the "successful-graft" patient group at one month (p = 0.0312), four months (p = 0.0158) and one year (p < 0.01) after the graft. The presence of active MMP-9 was highly significant of graft failure four months and one year after the graft (p < 0.0001). In contrast, MMP-2 increase was delayed, with significantly higher MMP-2 values than controls in all patients at four months (p = 0.0231) and one year (p = 0.0001) after the graft, but MMP-2 values could not discriminate between patient groups. CONCLUSIONS In our study, all cases of graft failure showed abnormally high levels of the active forms of metalloproteinase enzymes, and these values far exceeded the maximum control concentration. MMP-9 measurements in tears made between one and four months after corneal transplantation, and while local corticotherapy is steadily established, should help in predicting corneal graft rejection.
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161
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Stasia MJ, Allaoui C, Chabert M, Hadjian AJ, Morel F. A rapid, highly-resolving and sensitive method for quantifying neuron-specific enolase using Helena Laboratories Cardio-Rep. Clin Chim Acta 1998; 269:223-5. [PMID: 9526680 DOI: 10.1016/s0009-8981(97)00196-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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162
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Antras-Ferry J, Mahéo K, Chevanne M, Dubos MP, Morel F, Guillouzo A, Cillard P, Cillard J. Oltipraz stimulates the transcription of the manganese superoxide dismutase gene in rat hepatocytes. Carcinogenesis 1997; 18:2113-7. [PMID: 9395210 DOI: 10.1093/carcin/18.11.2113] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Oltipraz (4-methyl-5-(2-pyrazinyl)-1,2-dithiole-3-thione) (OPZ) is recognized as a potent chemoprotective agent against chemical-induced carcinogenesis in several animal models and is thought to act mainly by inducing phase II conjugating together with inhibiting phase I detoxication enzymes. The present study was undertaken to determine whether oltipraz can also influence expression of genes encoding antioxidant enzymes. In rat hepatocytes in primary culture, this compound was found to selectively induce the transcription of the manganese superoxide dismutase (Mn-SOD) gene while it had no effect on copper/zinc-SOD and glutathione peroxidase genes. Oltipraz increased Mn-SOD gene expression in a time- and dose-dependent manner by 2- to 3-fold and enhanced the binding activity of the nuclear factor kappa B within 30 min. Moreover, the increase in Mn-SOD gene transcription was associated with a 2- to 3-fold increase of free malondialdehyde and conjugated dienes, two markers of lipid peroxidation, an index of oxidative stress. These results suggest that in rat hepatocytes, oltipraz induced a production of reactive oxygen species that probably acted as second messengers in order to trigger the transcription of many genes. Such a mechanism of action of OPZ and other dithiolethiones would account for the broad spectrum of action of these anticarcinogenic compounds.
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163
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Decker C, Decker D, Morel F. Light Intensity and Temperature Effect in Photoinitiated Polymerization. ACS SYMPOSIUM SERIES 1997. [DOI: 10.1021/bk-1997-0673.ch006] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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164
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Imbert M, Chabardès D, Montégut M, Clique A, Morel F. Adenylate cyclase activity along the rabbit nephron as measured in single isolated segments. 1975. J Am Soc Nephrol 1997; 8:1608-17. [PMID: 9335391 DOI: 10.1681/asn.v8101608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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165
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Béziat F, Touraille S, Debise R, Morel F, Petit N, Lécher P, Alziari S. Biochemical and molecular consequences of massive mitochondrial gene loss in different tissues of a mutant strain of Drosophila subobscura. J Biol Chem 1997; 272:22583-90. [PMID: 9278413 DOI: 10.1074/jbc.272.36.22583] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
In the studied mutant strain of Drosophila subobscura, 78% of the mitochondrial genomes lost >30% of the coding region by deletion. The mutations was genetically stable. Despite this massive loss of mitochondrial genes, the mutant did not seem to be affected. Distribution of the two genome types, cell levels of mitochondrial DNA, steady-state concentrations of the mitochondrial gene transcripts, mitochondrial enzymatic activities, and ATP synthesis capacities were measured in the head, thorax, and abdomen fractions of the mutant strain in comparison with a wild type strain. Results indicate that the deleted genomes are detected in all fractions but to a lesser extent in the male and female abdomen. In all fractions, there is a 50% increase in cellular mitochondrial DNA content. Although there is a decrease in steady-state concentrations of mitochondrial transcripts of genes affected by deletion, this is smaller than expected. The variations in mitochondrial biochemical activities in the different fractions of the wild strain are upheld in the mutant strain. Activity of complex I (involved in mutation) nevertheless shows a decrease in all fractions; activity of complex III (likewise involved) shows little or no change; finally, mitochondrial ATP synthesis capacity is identical to that observed in the wild strain. This latter finding possibly accounts for the lack of phenotype. This mutant is a good model for studying mitochondrial genome alterations and the role of the nuclear genome in these phenomena.
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166
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Mahéo K, Morel F, Langouët S, Kramer H, Le Ferrec E, Ketterer B, Guillouzo A. Inhibition of cytochromes P-450 and induction of glutathione S-transferases by sulforaphane in primary human and rat hepatocytes. Cancer Res 1997; 57:3649-52. [PMID: 9288764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The isothiocyanate sulforaphane (SF) is thought to be a potential chemoprotective agent. Its effects on Phase I and Phase II enzymes of carcinogen metabolism in primary cultures of rat and human hepatocytes have been investigated. Northern blot analyses of rat hepatocytes showed a dose-dependent induction of mRNAs for rat glutathione S-transferases (rGSTs) A1/A2 and P1 but not M1. This was associated with enhanced levels of not only rGSTA1, A2, A4, A5, and P1 but also of rGSTs M1 and M2. On the other hand, the enzyme activities in rat hepatocytes associated with cytochromes P-450 (CYPs) 1A1 and 2B1/2, namely ethoxyresorufin-O-deethylase and pentoxyresorufin-O-dealkylase, respectively, were decreased in a dose-dependent manner. In SF-treated human hepatocytes, hGSTA1/2 but not hGSTM1 mRNAs were induced, and the expression of CYP1A2 was unaffected, whereas the expression of CYP3A4, the major CYP in human liver, was markedly decreased at both mRNA and activity levels. These observations demonstrate that in intact human and rat hepatocytes, SF may both induce a number of GSTs and cause enzyme inhibition of some but not all CYPs and, in the case of CYP3A4, inhibit both its enzyme activity and its expression.
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167
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Benna JE, Dang PM, Gaudry M, Fay M, Morel F, Hakim J, Gougerot-Pocidalo MA. Phosphorylation of the respiratory burst oxidase subunit p67(phox) during human neutrophil activation. Regulation by protein kinase C-dependent and independent pathways. J Biol Chem 1997; 272:17204-8. [PMID: 9202043 DOI: 10.1074/jbc.272.27.17204] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The respiratory burst oxidase of phagocytes and B lymphocytes catalyzes the reduction of oxygen to superoxide anion (O-2) at the expense of NADPH. This multicomponent enzyme is dormant in resting cells but is activated on exposure to an appropriate stimulus. The phosphorylation-dependent mechanisms regulating the activation of the respiratory burst oxidase are unclear, particularly the phosphorylation status of the cytosolic component p67(phox). In this study, we found that activation of human neutrophils with formyl-methionyl-leucyl-phenylalanine (fMLP), a chemotactic peptide, or phorbol myristate acetate (PMA), a stimulator of protein kinase C (PKC), resulted in the phosphorylation of p67(phox). Using an anti-p67(phox) antibody or an anti-p47(phox) antibody, we showed that phosphorylated p67(phox) and p47(phox) form a complex. Phosphoamino acid analysis of the phosphorylated p67(phox) revealed only 32P-labeled serine residues. Two-dimensional tryptic peptide mapping analysis showed that p67(phox) is phosphorylated at the same peptide whether fMLP or PMA is used as a stimulus. In addition, PKC induced the phosphorylation of recombinant GST-p67(phox) in vitro, at the same peptide as that phosphorylated in intact cells. PMA-induced phosphorylation of p67(phox) was strongly inhibited by the PKC inhibitor GF109203X. In contrast, fMLP-induced phosphorylation was minimally affected by this PKC inhibitor. Taken together, these results show that p67(phox) is phosphorylated in human neutrophils by different pathways, one of which involves protein kinase C.
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Morel F, Langouët S, Mahéo K, Guillouzo A. The use of primary hepatocyte cultures for the evaluation of chemoprotective agents. Cell Biol Toxicol 1997; 13:323-9. [PMID: 9298252 DOI: 10.1023/a:1007491525955] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Primary cultures of human and rat hepatocytes are widely used in pharmacotoxicological research. This model presents the advantages of retaining liver function for at least a few days, expressing both phase 1 and phase 2 enzymes, and responding to inducers. Recently we made use of primary hepatocytes to investigate the effects of chemoprotective agents on drug-metabolizing enzyme expression and activities. The treatment of rat and human hepatocytes with two chemoprotective agents, oltipraz (a synthetic derivative of 1,2-dithiole-3-thione) and sulforaphane (an isothiocyanate found in broccoli), clearly demonstrated that both of these compounds are inducers of glutathione transferases and transient inhibitors of cytochrome P450, suggesting that these two compounds could exert their chemoprotective effects by both reducing the formation of reactive metabolites of chemicals and enhancing their inactivation.
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169
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Langouët S, Mahéo K, Berthou F, Morel F, Lagadic-Gossman D, Glaise D, Coles B, Ketterer B, Guillouzo A. Effects of administration of the chemoprotective agent oltipraz on CYP1A and CYP2B in rat liver and rat hepatocytes in culture. Carcinogenesis 1997; 18:1343-9. [PMID: 9230277 DOI: 10.1093/carcin/18.7.1343] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The success of oltipraz (OPZ) [5-(2-pyrazinyl)-4-methyl-1,2-dithiole-3-thione] as a chemoprotective agent against aflatoxin B1 (AFB1)-induced hepatocarcinogenesis in the rat is thought to depend principally on its ability to enhance detoxication by inducing phase II enzymes, especially glutathione transferases. However, in primary cultures of human hepatocytes, we recently demonstrated that OPZ also has an important inhibitory effect on the major cytochromes P450 (CYPs) of human hepatic AFB1 metabolism. This has prompted a detailed study of the effect of OPZ on some CYPs involved in metabolism of AFB1 in the rat. Primary cultures of rat hepatocytes behaved similarly to human hepatocytes and responded to OPZ by inhibition of ethoxyresorufin-O-deethylase (EROD) and pentoxyresorufin-O-depentylase (PROD) activities mainly associated, respectively, with CYP1A and CYP2B. A time-course shows that this inhibition is largely reversible, with EROD and PROD activities reaching a minimum at 12 h and tending towards control values within 24 h. As is to be expected, the incubation of isolated microsomes with OPZ also inhibits CYP1A and 2B. The effect of OPZ on CYP1A is not a phenomenon limited to cells in culture, but also occurs in vivo. Using the whole animal, we were able to demonstrate that OPZ also transiently inhibited CYP1A activity in a rat given caffeine, by measuring the amounts of methylxanthines found in the serum. However, microsomes isolated from rats, that had been treated with OPZ in vivo, show no such inhibition, presumably because, since OPZ is a reversible inhibitor, it dissociates and is lost during the course of conventional procedures of microsomal preparation. This explains some earlier failures in studies of isolated microsomes to observe the inhibition of CYPs by OPZ. In addition to inhibiting their enzymatic activity, OPZ is also an inducer of CYP1A and 2B as shown by the increased levels of their mRNAs and of caffeine metabolism in vivo after 24 h or more. It is concluded that the mechanism of chemoprotection by OPZ, of toxic chemical metabolism in the rat, is complex and involves competitive inhibition of activation succeeded by induction of the enzymes of both activation and detoxication.
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Maheo K, Antras-Ferry J, Morel F, Langouët S, Guillouzo A. Modulation of glutathione S-transferase subunits A2, M1, and P1 expression by interleukin-1beta in rat hepatocytes in primary culture. J Biol Chem 1997; 272:16125-32. [PMID: 9195908 DOI: 10.1074/jbc.272.26.16125] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The influence of various cytokines on the expression of glutathione S-transferases (GSTs) was investigated in rat hepatocytes in primary culture. Only treatment of hepatocytes with interleukin-1beta (IL-1) was effective, resulting in a marked decrease in GSTs. Steady-state mRNA levels of rGSTA2 and M1 were strongly down-regulated by IL-1 in a dose-dependent manner after a 24-h exposure while rGSTP1 mRNA level was increased by a 48-h treatment. Similar effects of IL-1 were observed at the protein level. The response to IL-1 appeared to be specific for each subunit within GST gene families. In addition, IL-1 strongly suppressed the induction of rGSTA2 by 3-methylcholanthrene, oltipraz (a synthetic derivative of 1, 2-dithiole-3-thione), and phenobarbital and that of rGSTM1 by oltipraz and phenobarbital, whereas it was ineffective on rGSTP1 induction by these compounds. Using in vitro nuclear run-on transcription assay and Northern blot analysis of alpha-amanitin-treated cells, IL-1-mediated rGSTM1 mRNA decrease was found to result from mRNA destabilization. These results provide the first demonstration that IL-1 regulates some major GST subunits in hepatocytes by a post-transcriptional mechanism.
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Gaudin P, Razakaboay M, Surla A, Berthier S, Fauconnier J, Morel F, Phelip X. A study of metalloproteinases in fifty joint fluid specimens. REVUE DU RHUMATISME (ENGLISH ED.) 1997; 64:375-81. [PMID: 9513609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To study the activity and concentrations in joint fluid of gelatinases (A or matrix metalloproteinase (MMP)-2 and B or MMP-9), tissue inhibitor of metalloproteinases 1 (TIMP-1), and stromelysin-1 (MMP-3). METHODS Synovial fluid specimens obtained as part of a diagnostic or therapeutic procedure were studied. Protein levels were determined, cells counted, crystals looked for and microbiological studies done. Gelatinolytic activity was determined quantitatively using computerized zymography. Proteins were identified by electrotransfer and immunorevelation. TIMP-1 and stromelysin-1 were assayed using an ELISA. Results were confronted with laboratory test and clinical findings. RESULTS Of the 50 specimens studied, 25 were from joints with mechanical disorders and 25 from joints with inflammatory disorders. Activated MMP-2 was found in all the specimens, with no differences between the two groups. MMP-9 was found only in its inactive form. MMP-9, TIMP-1 and MMP-3 were found more often in inflammatory than in mechanical fluids and the levels of MMP-9 and TIMP-1 were correlated with neutrophil counts. In the 16 fluids from rheumatoid arthritis patients, levels of MMP-9 and TIMP-1 were closely correlated with serum C-reactive protein levels. CONCLUSIONS MMP-9, TIMP-1, and MMP-3 levels show striking differences between inflammatory and mechanical joint fluids.
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Morel F, Mercier S, Roux C, Clavequin MC, Bresson JL. Estimation of aneuploidy levels for 8, 15, 18, X and Y chromosomes in 97 human sperm samples using fluorescence in situ hybridization. Fertil Steril 1997; 67:1134-9. [PMID: 9176456 DOI: 10.1016/s0015-0282(97)81451-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To estimate the mean frequency of aneuploidy levels of chromosomes 8, 15, 18, X, and Y in human sperm, while minimizing the effect of individual factors by analyzing sperm samples from a large set of patients. DESIGN Prospective randomized analysis of sperm nuclei by fluorescence in situ hybridization. SETTING University-based laboratory for reproductive biology. PATIENT(S) One hundred two patients with a large distribution of sperm parameters, randomly selected from volunteers who had presented seeking a semen analysis. INTERVENTION(S) The sperm samples were prepared for fluorescence in situ hybridization. MAIN OUTCOME MEASURE(S) The disomy frequencies for chromosomes 8, 15, 18, and sex chromosomes were determined using fluorescence in situ hybridization. RESULT(S) The mean frequencies of disomy for autosomes were 0.18% for chromosome 8, 0.06% for chromosome 15, 0.2% for chromosome 18, and 0.24% for gonosomes (XX, 0.04%; YY, 0.05%; XY, 0.15%). CONCLUSION(S) This study confirms other previous evaluations on restricted numbers of patients. Our results seem to confirm a relative equiprobability of disomy frequencies concerning the different chromosomal pairs during male meiosis.
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Gaudin P, Berthier S, Barro C, Zaoui P, Morel F. Proteolytic potential of human neutrophil membranes. Eur J Cell Biol 1997; 72:345-51. [PMID: 9127734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A synergistic role for proteases in the degradation of extracellular matrix proteins has been proposed. Plasma membrane was isolated from a neutrophil homogenate, on a sucrose gradient, and shown to activate gelatinolysis when purified 92 kDa gelatinase was added to the medium. This stimulatory activity was enhanced by the addition of phorbol 12-myristate 13-acetate (PMA), in a dose-dependent manner, and was partially sensitive to phenylmethylsulfonyl fluoride treatment. The effect was abolished by the addition of 1 M KCl or 0.05% Brij 35 extraction. Both elastase and urinary type plasminogen activator were shown to be involved in the process. Moreover, upon neutrophil stimulation by PMA, 92 kDa gelatinase, as elastase, became associated with the plasma membrane, as shown by a subcellular fractionation experiment. These in vitro observations suggest that human neutrophils may be able, in vivo, to recruit endogenous or exogenous proteinases to mediate proteolysis associated with diapedesis and chemotactism during the inflammation process.
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Antras-Ferry J, Mahéo K, Morel F, Guillouzo A, Cillard P, Cillard J. Dexamethasone differently modulates TNF-alpha- and IL-1beta-induced transcription of the hepatic Mn-superoxide dismutase gene. FEBS Lett 1997; 403:100-4. [PMID: 9038369 DOI: 10.1016/s0014-5793(97)00033-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effects of cytokines, tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and the synthetic glucocorticoid dexamethasone on the gene expression of antioxidant enzymes have been investigated in rat hepatocytes in primary culture. First, we observed that the hepatocyte culture process induced a strong but transient induction of manganese superoxide dismutase (Mn-SOD) gene expression, whereas copper-zinc superoxide dismutase, glutathione peroxidase and catalase genes were down-regulated. IL-1beta and TNF-alpha both stimulated specifically Mn-SOD gene expression in a time-dependent manner. TNF-alpha rapidly induced Mn-SOD gene expression while IL-1beta was a strong but slow inducer of this gene. Both cytokines acted at the transcriptional level as shown by nuclear run on assays. Dexamethasone prevented the TNF-alpha- but not the IL-1beta induced up-regulation of Mn-SOD gene transcription by a mechanism likely to involve the glucocorticoid receptor. Moreover this glucocorticoid did not suppress the TNF-alpha-induced increase of NF-kappaB binding activity. These results suggest that IL-1beta and TNF-alpha regulate Mn-SOD gene transcription by different pathways.
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Doré P, Lelièvre E, Morel F, Brizard A, Fourcin M, Clemént C, Ingrand P, Daneski L, Gascan H, Wijdenes J, Gombert J, Preud'homme JL, Lecron JC. IL-6 and soluble IL-6 receptors (sIL-6R and sgp130) in human pleural effusions: massive IL-6 production independently of underlying diseases. Clin Exp Immunol 1997; 107:182-8. [PMID: 9010274 PMCID: PMC1904539 DOI: 10.1046/j.1365-2249.1997.d01-889.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
IL-6, soluble IL-6 receptor (sIL-6R) and soluble gp130 (sgp130) levels were measured in sera and pleural effusions from 42 patients with metastatic carcinoma, non-Hodgkin's lymphoma, tuberculosis, cardiac failure and miscellaneous diseases. Pleural IL-6 levels measured by ELISA were very high in all patient groups (mean 34.8 +/- 15.3 ng/ml) without significant difference according to diseases. IL-6 was shown to be biologically active in a proliferative assay. Serum IL-6 levels were low (0.049 +/- 0.014 ng/ml) and did not correlate with pleural fluid levels. Pleural IL-6 levels correlated with the number of polymorphonuclear cells in pleural fluid (P < 0.03). Pleural sIL-6R levels (76 +/- 8 ng/ml) were always lower than serum levels (196 +/- 12 ng/ml; P < 0.0001) but correlated with them (P < 0.01). Pleural sIL-6R and albumin levels correlated (P < 0.01), suggesting a transudation of sIL-6R from the serum. Pleural sgp130 levels (10.9 +/- 1.0 ng/ml) were lower than serum levels (24.6 +/- 2.8 ng/ml; P < 0.002). After gel filtration of pleural fluid, the bulk of IL-6 (> 90%) was recovered in a 15,000-30,000 fraction, corresponding to the expected mol. wt of free IL-6. These results suggest a production and a sequestration of IL-6 in the pleural cavity in all studied conditions.
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