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61.
Sylviane Olschwang Richard Fabre Pierre Laurent-Puig Anne Vassal Bernard Hamelin Yusuke Nakamura Gilles Thomas 《Human genetics》1992,88(6):658-660
Summary The EF5.44 locus is in close proximity to the chromosome 5 region to which the genetic defect responsible for familial adenomatous polyposis has been mapped. We have devised two oligonucleotides that promote the specific polymerase chain reaction (PCR) amplificiation of a 365-bp sequence in this region. Analysis by denaturing gradient gel electrophoresis of the resulting fragment has unravelled individual differences that could be identified as a single base pair change in aMnlI restriction site. This PCR assayable polymorphism increases the informativeness at this locus, and should be useful in the presymptomatic diagnosis of familial adenomatous polyposis. 相似文献
62.
Ans M. W. van den Ouweland Marian Verdijk Marcel M. A. M. Mannens Bernard A. van Oost 《Human genetics》1992,90(1-2):144-146
Summary Inactivation of one or more tumor-suppressor genes on the short arm of chromosome 11 is thought to play a role in the etiology of Wilms' tumor. A candidate gene, QM, was recently isolated by subtractive hybridization between a tumorigenic cell line (deleted for part of 11p) and a non-tumorigenic cell line (the tumorigenic cell line carrying an extra t(X;11)copy). We show here with an exon-specific polymerase chain reaction that the genomic homolog of the QM cDNA is located in the G6PD-color vision genes region in Xq28. No homologous sequences could be detected on 11p. Our experiments indicate that the QM gene is not involved in the suppression of Wilms' tumor. 相似文献
63.
Heiko Traupe Dietmar Müller David Atherton D. Chester Kalter Frans P. M. Cremers Bernard A. van Oost Hans-Hilger Ropers 《Human genetics》1992,89(6):659-665
Summary Homology with the mouse bare patches mutant suggests that the gene for the X-linked dominant chondrodysplasia punctata / ichthyosis / cataract / short stature syndrome (Happle syndrome) is located in the human Xq28 region. To test this hypothesis, we performed a linkage study in three families comprising a total of 12 informative meioses. Multiple recombinations appear to exclude the Xq28 region as the site of the gene. Surprisingly, multiple crossovers were also found with 26 other markers spread along the rest of the X chromosome. Two-point linkage analysis and analysis of recombination chromosomes seem to exclude the gene from the entire X chromosome. Three different mechanisms are discussed that could explain the apparent exclusion of an X-linked gene from the X chromosome by linkage analysis: (a) different mutations on the X chromosome disturbing X inactivation, (b) metabolic interference, i.e. allele incompatibility of an X-linked gene, and (c) an unstable pre-mutation that can become silent in males. We favour the last explanation, as it would account for the unexpected sex ratio (MF) of 1.21 among surviving siblings, and for the striking clinical variability of the phenotype, including stepwise increases in disease expression in successive generations. 相似文献
64.
Competitive exclusion of diarrheagenic Escherichia coli (ETEC) from human enterocyte-like Caco-2 cells by heat-killed Lactobacillus 总被引:7,自引:0,他引:7
Gilles Chauvière Marie-Hélène Coconnier Sophie Kerneis Arlette Darfeuille-Michaud Bernard Joly Alain L. Servin 《FEMS microbiology letters》1992,91(3):213-217
Diarrheagenic Escherichia coli (ETEC) bearing CFA/I or CFA/II adhesive factors specifically adhere onto the brush border of the polarized epithelial human intestinal Caco-2 cells in culture. Heat-killed Lactobacillus acidophilus strain LB, that adheres onto Caco-2 cells, inhibits diarrheagenic Escherichia coli adhesion in a concentration-dependent manner. Since the L. acidophilus does not express ETEC-CFA adhesive factors, it can be postulated that the heat-killed L. acidophilus LB cells inhibit diarrheagenic E. coli attachment by steric hindrance of the human enterocytic ETEC receptors. 相似文献
65.
Gérald Chouinard Charles Vincent Stuart B. Hill Bernard Panneton 《Journal of Insect Behavior》1992,5(3):385-394
From 12 to 19 May 1987, during Morspur apple bloom, 21 radioactively labeled (65
Zn) adult plum curculios, Conotrachelus nenuphar (Herbst), were released within a field cage containing four dwarf apple trees and located three times a day. A technique was developed for quickly obtaining (x, y, z)coordinates of location for adults foraging within apple trees. Cyclic patterns of behavior were detected using spectral analysis procedures. Over 70% of plum curculios exhibited diel periodicity with respect to activity and rate of movement, 36% exhibited such periodicity with respect to presence in the trees, and 27% with respect to movements from the center to the periphery of the canopy. Presence in fruit clusters, height in the trees, and movements along east-west and north-south axes showed little or no periodicity. Factors triggering cyclic behavior and practical implications of the results are discussed. 相似文献
66.
Françoise Farace Anne-Marie Le Ridant Bernard Escudier Thierry Hercend Frédéric Triebel 《Biotherapy》1992,5(1):11-20
We have attempted to improve negative selection procedures for the large scale purification of human CD
in3
–
CD56+ NK cells. In a series of experiments, purifications of NK cells from 108 PBMC were performed by T cell depletion using either direct or indirect anti-CD3 labeling and the Magnetic Activated Cell Separation (MACS) procedure. Contaminating CD3+ cells were still present using either one of these two different T cell depletion protocols as shown by phenotyping IL-2 supplemented cell cultures on day 12. A second cycle of purification was therefore added. When MACS and Dynabeads were compared as complementary procedures to the first MACS cycle starting with 108 cells, the Dynabeads method was found to be superior to the MACS with regard to the elimination of residual T cells. Starting from 109 PBMC, we showed that this MACS+Dynabeads procedure gave similar satisfactory results when compared to the scaling-up of a previously established two steps procedure using Dynabeads. These two approaches (MACS+Dynabeads and 2 cycles of Dynabeads) have been also tested in a clinical setting to purify NK cells from cancer patients prior toin vitro expansion. The results indicate that the two methods are equivalent with respect to purity and recovery rate; a slight advantage in terms of feasibility was found in favor of 2 cycles of Dynabeads. 相似文献
67.
Detection of Pneumocystis carinii in serum of AIDS patients with Pneumocystis pneumonia by the polymerase chain reaction. 总被引:3,自引:0,他引:3
N Schluger K Sepkowitz D Armstrong E Bernard M Rifkin A Cerami R Bucala 《The Journal of protozoology》1991,38(6):240S-242S
Amplification of DNA by the polymerase chain reaction (PCR) offers a highly sensitive and specific method for detecting DNA sequences in biological samples. We applied this technology to develop an assay for the P. carinii dihydrofolate reductase (DHFR) gene. This assay was found to be sensitive enough to detect as little as 1 organism-'equivalent' of DHFR DNA. In rats with experimentally-induced P. carinii pneumonia, DHFR DNA amplification demonstrated the presence of pulmonary P. carinii 2 wk prior to the onset of histopathological changes. When rat serum was analyzed by PCR, serum P. carinii DNA was found in 5 of 14 experimental rats. Finally, P. carinii DNA was detected in the serum of 7 of 18 patients (39%) with AIDS and active P. carinii pneumonia. These results suggest that circulating serum P. carinii DNA can be detected frequently in the course of pulmonary infection and may represent a blood-borne phase of infection. The PCR detection of P. carinii DNA provides a useful tool to study the natural history of P. carinii infection and may offer a non-invasive diagnostic procedure in some patients with P. carinii pneumonia. 相似文献
68.
Murielle Reboul Bernard Frangoulis Anna Rocca Laurent Degos Marika Pla 《Immunogenetics》1991,34(3):196-200
As a basis for the characterization of mouse T cells involved in the recognition of xenogeneic HLA molecules, a panel of HLA-B27-reactive cytotoxic T-cell clones was generated upon stimulation by cells from HLA-B27-transgenic mice. The HLA-B27-induced T-cell response was found to comprise two categories of clones: some recognizing HLA-B27 independent of H-2 molecules expressed by the target cells (unrestricted clones), others recognizing HLA-B27 in an H-2 restricted manner. The unrestricted clones exhibited diverse specificities, as judged from their various cross-reactivities with other xenogeneic (HLA) or allogeneic (H-2) molecules. In addition, although most of the unrestricted clones were able to react with both mouse and human HLA-B27-transgenic mice. The HLA-B27 induced T-cell which reacted only with HLA-B27-positive mouse, and not human cells. These findings illustrate that both H-2-restricted and unrestricted T cells with diverse species contribute to HLA-B27-xenorecognition. 相似文献
69.
Josep Vilardell John Mundy Bodil Stilling Bernard Leroux Maria Pla Georges Freyssinet Montserrat Pagès 《Plant molecular biology》1991,17(5):985-993
The maizerab17 gene is expressed in different plant parts in response to ABA and osmotic stress (J. Vilardellet al., Plant Mol Biol 14 (1990) 423–432). Here we demonstrate that 5 upstream sequences of therab17 gene confer the appropriate patterns of expression on the chloramphenicol acetyl transferase (CAT) reporter gene in transgenic tobacco plants, as well as in protoplasts derived from cultured rice cells. Specifically, a CAT construct containing a large 5 upstream fragment ofrab17 (–1330/+29) results in high levels of CAT activity in embryos, leaves and roots of transgenic plants subjected to water stress or ABA treatment. Transient expression assays in rice protoplasts transfected with CAT genes fused torab17 promoter deletions indicate that a 300 bp DNA fragment (–351/–102) is sufficient to confer ABA responsiveness upon the reporter gene. Furthermore, a 100 bp sequence (–219/–102) is capable of conferring ABA responsiveness upon a minimal promoter derived from the 35S CaMV promoter. Gel retardation experiments indicate that maize nuclear proteins bind to this fragment. This region of 100 bp contains a sequence (ACGTGGC) which has been identified as an abscisic acid response element in studies of other ABA-responsive plant genes. 相似文献
70.