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For the first time, combined immunophenotyping and fluorescence in situ hybridization (FISH) technique according to the ”fluorescence immunophenotyping and interphase cytogenetics as a tool for investigation of neoplasms” (FICTION) technique have been successfully applied in solid tumors. Thus, we were able to visualize the antigen expression of cells with chromosomal deletions of a tumor suppressor region directly. In six breast carcinoma cell lines, we investigated the correlation between estrogen receptor (ER) expression status and deletions of the estrogen receptor gene (ESR). To screen for deletions of the ESR gene, dual-color FISH was performed with a YAC (yeast artificial chromosome) probe containing the ESR gene and, as internal control, with a centromeric probe of chromosome 6. Deletions of the ESR gene were detected in four of six cell lines. For direct comparison of ER expression with the copy number of the ESR gene at the single cell level, immunophenotyping with mouse anti-human ER antibody was combined with FISH with the YAC probe containing the ESR gene according to the FICTION technique. There was no correlation between lack of or reduced ER expression and deletions of the ESR gene. One cell line with deletions of the ESR gene did express ER on the protein level, while another cell line without a deletion did not. Cells with deletions of the ESR gene were either ER expression positive or negative. The staining intensity of ER expression was not associated with the copy number of the ESR gene. Thus, this FICTION study unequivocally shows that deletions of the ESR gene are not the major cause of absent or reduced ER expression in breast carcinoma cell lines. Received: 6 September 1999 / Accepted: 14 September 1999  相似文献   
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In a human in-vitro fertilization (IVF) programme, the effect of co- culture of embryos with human fibroblasts was evaluated with respect to pregnancy rate and embryo development. Patients were included in the study after giving informed written consent. The IVF treatments were randomly assigned by stratification of both age (<36 versus > or =36 years) and previous IVF attempts (yes versus no). After fertilization was established, the zygotes were transferred to a 4-well dish with or without fibroblasts and cultured for 2 days. On the third day after ovum pick-up (OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were scored and a maximum of three embryos was transferred. Supernumerary embryos of good quality were cryopreserved. The design of this study was a group sequential trial with the objective of detecting differences between pregnancy rates following IVF with conventional incubation or incubation in co-culture with fibroblasts. This design included one evaluation at half-way data collection. In the study, 148 patients had an OPU, of whom 77 were allocated to the co-culture group. There was no statistically significant difference in pregnancy rate, cell number and embryo quality between the two groups. The ongoing pregnancy rate per embryo transfer was 27% in co-culture and 30% in the conventional culture group. The implantation rates per transferred embryo were 17 and 18% respectively. Using a multivariate logistic regression model for the probability of ongoing pregnancies, the odds ratio of co-culture, adjusted for age and previous IVF attempts, was not statistically significant. In conclusion, co-culture with human fibroblasts does not contribute to an improvement of embryo quality nor to a higher pregnancy rate after IVF in an unselected group of patients.   相似文献   
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Summary The anatomic constraints imposed on a total artificial heart (TAH) require specific anatomic studies. A thoracic anatomic study was performed with a scanning device equipped with three-dimensional (3-D) reconstruction software on 15 male patients, between the ages of 41 to 63 years (52 ± 6 years). All were candidates for heart transplantation. The 3-D reconstructions of the cardiovascular structures obtained from surgical anatomy data specific to TAH implantation allowed a volumetric measurement of these structures. A modeling diagram of these structures permitted reproducible quantitative measurements of the 35 geometrical parameters which characterized shape, orientation, and position of these structures within the thorax. Most of the measured parameters were characterized by low variability (coefficient of variation from 10 to 25%).
Modélisation tridimensionnelle de l'anatomie du cur et des gros vaisseaux
Résumé Les contraintes anatomiques imposées au cur artificiel total (CAT) nécessitent des études anatomiques spécifiques. Une étude anatomique thoracique a été réalisée avec un scanner doté d'un logiciel de reconstruction tridimensionnelle (3-D) chez 15 patients, tous de sexe masculin, agés de 41 à 63 ans (52 ± 6 ans), et candidats à une transplantation cardiaque. Les reconstructions 3-D des structures cardio-vasculaires réalisées selon les données de l'anatomie chirurgicale propre à l'implantation du CAT ont permis la mesure volumétrique de ces structures. Un schéma de modélisation de ces structures a permis des mesures quantitatives reproductibles de 35 paramètres géométriques caractéristiques de la forme, de l'orientation, de la position de ces structures dans le thorax. Les résultats de ces mesures ont pu être exprimés en termes statistiques. La plupart des paramètres mesurés étaient caractérisés par une faible variabilité (coefficients de variations de 10 à 25%).
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The persistence of Cytomegalovirus (CMV) with alteration of cell surface expression in certain tissues may initiate the tissue destruction that leads to the clinical manifestations of Sjogren's Syndrome. Salivary gland and lacrimal gland ductal cells are immunologically attacked due to CMV antigenic expression. The destruction of these ducts leads to xerostomia and keratonconjunctivitis sicca, the hallmarks of Sjogren's Syndrome.  相似文献   
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The gold standard for bone substitution is the autologous bone graft, but because of its limited supply and the associated morbidity, the search for synthetic alternatives is necessary. A new in situ setting tricalcium phosphate cement was implanted in a trepanation defect (9.4 mm diameter, 10 mm depth) in the distal femoral epiphysis of sheep. Empty cavities and autologous bone graft were used as controls. Histologic and histomorphometric examinations were carried out after 12 weeks. Nearly 90% of the implanted cement was resorbed and replaced by ingrown bone with close contact between surrounding bone, new bone, and remaining cement particles. The amount of bone in the defect area was significantly higher in defects filled with cement relative to defects filled with autologous bone graft (mean 27 vs. 21%, 95% confidence intervals 23 to 31 and 18 to 23, p = 0.026). In conclusion, this new in situ setting cement is bioactive, resorbable, and osteoconductive. It will be useful as an alternative to autologous bone graft to fill stable defects.  相似文献   
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Summary The angular points are the ligamentous and tendinous structures that reinforce the posteromedial and posterolateral capsule of the knee and share in fixation of the posterior horns of the menisci. They are often damaged in acute injuries and this is usually associated with ruptures of the cruciate and collateral ligaments and may add to the degree of laxity. We describe the normal appearance of these structures in terms of the sectional anatomy, correlated with the lesional appearances of complete and incomplete ruptures and associated meniscal detachments as shown by clinical testing and arthrotomy findings.
IRM des points d'angle du genou : bases anatomiques et applications aux genoux traumatiques
Résumé Les points d'angle sont des structures ligamentaires et tendineuses qui renforcent la capsule postéro-médiale et postéro-latérale et participent à la fixation des cornes postérieures des ménisques. Leurs lésions, fréquentes au cours des traumatismes aigus, sont généralement associées à des ruptures des ligaments croisés et des ligaments collatéraux et peuvent être source d'une aggravation de la laxité. Nous rapportons, en corrélation avec l'anatomie en coupe, l'aspect normal de ces structures, et en corrélation avec les données de l'arthrotomie et du testing les aspects lésionnels observés au cours des traumatismes : ruptures complètes, incomplètes et désinsertions méniscales associées.
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Primary central nervous system lymphomas (PCNSL) constitute diffuse large B-cell lymphomas arising in and remaining confined to the brain. Little information is available on cytogenetic changes in PCNSL, and recurrent chromosomal translocations have not yet been identified. Fluorescence in situ hybridization (FISH) of a series of 13 PCNSL from immunocompetent patients revealed 3 cases with signal patterns of a BCL6-specific probe suggesting a breakpoint in this oncogene locus in chromosome band 3q27. Here, we describe cloning of the translocation breakpoints by long-distance inverse polymerase chain reaction (LDI-PCR) in 2 of these tumors. Both breakpoints affected the first intron of BCL6. In one PCNSL, the HSPCA (HSP90A) gene in 14q32.31 was identified as BCL6 partner. In the second lymphoma, the gene encoding glyceraldehyde-3-phosphate dehydrogenase (GAPD) on 12p13.31 was detected as a hitherto unknown partner of BCL6. Our results suggest translocation-mediated BCL6 oncogene activation as a so far unknown pathogenetically relevant mechanism in PCNSL.  相似文献   
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