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Recent studies using human breast cancer cell lines, animal models, and human tissue biopsies have suggested a close correlation between the expression of the peripheral-type benzodiazepine receptor (PBR) and the progression of breast cancer. This study investigates the genetic status of the PBR gene in two human breast cancer cell lines: MDA-MB-231 cells, which are an aggressive breast cancer cell line that contains high levels of PBR, and MCF-7 cells, which are a nonaggressive cell line that contains low levels of PBR. Both DNA (Southern) blot and fluorescence in situ hybridization analyses indicate that the PBR gene is amplified in MDA-MB-231 relative to MCF-7 cells. These data suggest that PBR gene amplification may be an important indicator of breast cancer progression.  相似文献   
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Loss of heterozygosity (LOH) of the wild-type BRCA1/2 allele is a reproducible event in breast tumors of BRCA1/2 mutation carriers, but it is unknown if this allelic loss occurs only in association with recognizable histopathologic abnormalities. We evaluated the early genomic changes that occur in the mammary glands of patients with increased predisposition to breast cancer due to germline mutations in the BRCA1/2 genes. We tested the hypothesis that these genomic changes may be detected, not only in histologically abnormal and malignant breast tissues, but also in morphologically normal tissues and in areas with pathologically benign changes. Samples were obtained from five breast cancer patients: four BRCA1 carriers and one BRCA2 carrier. In each case, nontumor tissue areas surrounding the tumor or from other locations of the breast were isolated using laser capture microdissection. We evaluated 29 areas showing normal terminal ductal lobular units (TDLUs) or histopathologically benign changes (in particular, sclerosing adenosis), using a panel of polymorphic dinucleotide microsatellite markers for the BRCA1 gene and other chromosome 17 loci, for the BRCA2 gene and other chromosome 13 loci, and for the FHIT gene on 3p14.2. Overall, we analyzed a total of 105 samples of nontumor tissues; LOH was detected in 59 of the 105 (56%). In the normal TDLUs, 15 of 30 samples (50%) showed LOH; in the tissues with benign proliferative changes, such as sclerosing adenosis, 44 of 75 samples showed LOH (59%). Our results suggest that there is a field effect of early genetic events preceding morphologic changes in the mammary glands of BRCA mutation carriers.  相似文献   
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Seckel syndrome is a rare autosomal recessive disorder. The classical presentation includes pre- and postnatal growth deficiency, mental retardation, and characteristic facial appearance. There have been several reports of associated hematological abnormalities and chromosomal breakage, findings suggestive of Fanconi anemia (FA). We tested for these findings in two Arabic patients with this syndrome. We compared the growth profile of lymphoblastoid cells from our patients and their parents with the FA group A cell line HSC72 in the presence and absence of mitomycin C (MMC). By Western analysis, we also determined the expression of FAA and FAC, two FA disease gene products that together account for approximately 80% of FA. Unlike HSC72 cells, cells from the patients were resistant to MMC, and both FAA and FAC proteins were expressed at similar levels in all cell lines. There is an increasing recognition of clinical variability and perhaps genetic heterogeneity in Seckel syndrome. Our results demonstrate that cross-link sensitivity comparable to FA is not a uniform finding in patients with Seckel syndrome.  相似文献   
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We performed genetic analysis for carrier detection for several at-risk females in a four-generation Duchenne muscular dystrophy (DMD) pedigree using deletion analysis. We demonstrated that dosage analysis is a suitable alternative method to determine the carrier status of female relatives of DMD patients shown to have a deletion within the DMD gene. Subsequently, we diagnosed an affected male fetus for an at-risk female shown to be a DMD carrier by deletion analysis. The usefulness of deletion and linkage analysis are compared. In this family, linkage analysis was complicated by the unavailability of key family members, two recombination events and by previously undisclosed nonpaternity. We found that dosage analysis was more efficient than linkage for carrier evaluation in this family.  相似文献   
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A 4-month-old child with multiple anomalies was determined to have an interstitial deletion of chromosome 15, i.e., del(15) (q12q14). The deletion appears not to be a typical deletion of 15q12 such as seen in Angelman and Prader-Willi syndromes, but appears to be more distal, involving either loss of all of 15q12 and part of 15q14, or part of 15q12 and most of 15q14. In either case, 15q13 is missing. Fluorescent in situ hybridization with probes for 15 centromere (D15Z), pericentromeric satellite sequences (D15Z1), and chromosome 15 painting probes shows the deleted chromosome to involve only 15 and no other acrocentric chromosome. Hybridization with probes for the AS and PWS loci (D15S11 and GABAB3, Oncor) show both sites to be intact in the deleted 15. The case is compared with two other reports with overlapping interstitial deletions of proximal 15q, neither of which shows typical features of Angelman or Prader-Willi syndromes.  相似文献   
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Our objective was to elaborate a functional map of the globus pallidus by correlating the intrapallidal localization of quadripolar electrodes implanted in parkinsonian patients with the clinical effect of the stimulation of each contact. Five patients with L-DOPA-responsive Parkinson's disease presenting severe motor fluctuations and L-DOPA-induced dyskinesias were treated by continuous bilateral high-frequency stimulation of the globus pallidus. The effects of stimulation on parkinsonian disability were tested through each of the four stimulating contacts of each electrode. The anatomical localization of each of the stimulating contacts was determined by confronting the pre- and post-operative magnetic resonance imaging with the anatomical atlas of Schaltenbrand and Wharen.(34) The registration procedure comprised digitization of the atlas, the use of deformation tools to fit atlas sections with magnetic resonance imaging sections, and three-dimensional reconstruction of both the atlas and the magnetic resonance imaging sections. Analysis of the 32 stimulating contacts tested did not reveal a somatotopic organization in the pallidal region investigated but demonstrated that high-frequency stimulation had contrasting effects depending on whether it was applied to the external or the internal pallidum. Akinesia was improved by stimulation of the external pallidum but worsened by stimulation of the internal pallidum. In contrast, parkinsonian rigidity was improved by stimulation of either part of the pallidum. The areas in the internal pallidum where stimulation worsened akinesia were those in which stimulation reduced or suppressed L-DOPA-induced dyskinesias. Conversely, stimulation applied to the external pallidum induced dyskinesias. The fact that rigidity was improved by stimulation of the internal and external pallidum suggests that the neuronal bases of parkinsonian rigidity are different from those of akinesia and dyskinesias. The effect on akinesia and dyskinesias is in agreement with the current model of basal ganglia circuitry(10) if high-frequency stimulation activates rather than inhibits pallidal neurons, a possibility which is very likely since there are marked anatomical, biochemical and electrophysiological differences between the globus pallidus and the subthalamic nucleus.This study demonstrates that high-frequency stimulation of the globus pallidus in parkinsonian patients has contrasting effects depending on whether it is applied to the external or the internal part of this nucleus. The effect on akinesia and dyskinesias suggests that stimulation activates pallidal neurons, a result which challenges the generally accepted concept that high-frequency stimulation inactivates neurons in the region stimulated.  相似文献   
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Background:To construct a modified model for reporting and grading of postoperative complications after the mid-urethral sling (MUS) procedure based on the Clavien-Dindo classification. In addition, complications of three different types of MUS were compared.Materials and methods:A PubMed search for postoperative complication after MUS was carried out for the period between January 1990 and July 2018. Reported complications were stratified in a plate form designed in accordance with grades of the Clavien-Dindo classification. Then, the proposed model was applied on reported complications in 160 females who underwent three different procedures of MUS (transvaginal tape [TVT], transobturator tape [TOT], and autologous fascial sling) with a minimum follow-up of 24 months.Results:The mean ± SD age at time of surgery was 46 ± 7 years. TVT was carried out in 75 (47%) patients, TOT in 40 (25%), and fascial sling in 45 (28%). The total number of complications was 62 in 43 (26.8%) patients. The vast majority of complications were Grade I and Grade II 19 (12%) and 21 (13%) out of 160 patients, respectively. Transient postoperative voiding difficulty (Grade II) and de novo urgency (Grade II) were the most prevalent complications in the fascial sling method (15.4% for each), whereas transient thigh pain (Grade II) was the most frequently reported complication after TOT (10%). Life-threatening vascular injury (Grade IV-a) was a serious complication in TVT cases.Conclusions:Postoperative complications of the MUS could be graded according to Clavien''s classification. The vast majority of complications were Graded I or II. TVT can cause serious life-threatening complications.  相似文献   
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