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991.
D2-40, a novel monoclonal antibody against the M2A antigen as a marker to distinguish hemangioblastomas from renal cell carcinomas 总被引:9,自引:0,他引:9
Hemangioblastomas (HB) are characterized by the presence of vacuolated tumor cells resembling the tumor cells seen in clear cell renal cell carcinomas (CRCC). The distinction between HB and metastatic CRCC in the brain is critical as they have different therapeutic and prognostic ramifications. The issue is further complicated by the possibility of both HB and metastatic CRCC in brains of patients with Von Hippel Lindau (VHL) disease. We studied the expression of a novel monoclonal antibody D2-40, which recognizes an oncofetal antigen (M2A) in HB and CRCC, by immunohistochemistry. The vacuolated tumor cells in all HB were stained positively with D2-40. Nineteen of 23 (83%) HB showed strong, membranous staining in the vacuolated tumor cells, and 4 of 23 (17%) showed weaker staining. No expression was seen in CRCC, either primary in the kidney (0/20), or metastatic CRCC in the brain (0/8). Three of the patients with HB also had VHL disease, and no difference was seen in D2-40 staining of HB in patients with or without VHL disease. Two of these three VHL disease patients had both primary CRCC and HB resected at our institution. In these two patients, strong D2-40 expression was seen in the HB, but no expression was seen in the CRCC, underlying the utility of this marker in distinguishing HB from CRCC in patients with VHL disease in addition to sporadic cases. In summary, the monoclonal antibody D2-40 is a useful marker to distinguish HB from CRCC. 相似文献
992.
Zeilhofer HU Studler B Arabadzisz D Schweizer C Ahmadi S Layh B Bösl MR Fritschy JM 《The Journal of comparative neurology》2005,482(2):123-141
Although glycine is a major inhibitory transmitter in the mammalian CNS, the role of glycinergic neurons in defined neuronal circuits remains ill defined. This is due in part to difficulties in identifying these cells in living slice preparations for electrophysiological recordings and visualizing their axonal projections. To facilitate the morphological and functional analysis of glycinergic neurons, we generated bacterial artificial chromosome (BAC) transgenic mice, which specifically express enhanced green fluorescent protein (EGFP) under the control of the promotor of the glycine transporter (GlyT) 2 gene, which is a reliable marker for glycinergic neurons. Neurons expressing GlyT2-EGFP were intensely fluorescent, and their dendrites and axons could be visualized in great detail. Numerous positive neurons were detected in the spinal cord, brainstem, and cerebellum. The hypothalamus, intralaminar nuclei of the thalamus, and basal forebrain also received a dense GlyT2-EGFP innervation, whereas in the olfactory bulb, striatum, neocortex, hippocampus, and amygdala positive fibers were much less abundant. No GlyT2-EGFP-positive cell bodies were seen in the forebrain. On the subcellular level, GlyT2-EGFP fluorescence was colocalized extensively with glycine immunoreactivity in somata and dendrites and with both glycine and GlyT2 immunoreactivity in axon terminals, as shown by triple staining at all levels of the neuraxis, confirming the selective expression of the transgene in glycinergic neurons. In slice preparations of the spinal cord, no difference between the functional properties of EGFP-positive and negative neurons could be detected, confirming the utility of visually identifying glycinergic neurons to investigate their functional role in electrophysiological studies. 相似文献
993.
Niederstätter H Berger B Oberacher H Brandstätter A Huber CG Parson W 《International journal of legal medicine》2005,119(1):1-9
In order to determine to what extent the separate analysis of both copies of DYS385 improves Y-chromosomal short tandem repeat (Y-STR) haplotyping, we followed a recently published protocol for the separate amplification of DYS385a and DYS385b with modifications and compared the results with those obtained by conventional analysis in a population sample comprising 133 unrelated Caucasian males from Austria. Additionally, we typed all markers of the minimal haplotype (minHT) and a set of Y-chromosomal single nucleotide polymorphisms (Y-SNPs) in order to interpret the STR data depending on the Y-SNP haplogroup structure. The separate amplification of DYS385a and b improved the power of discrimination of this marker when compared to the results obtained with the conventional non-locus-discriminating amplification strategy. However, the degree of this improvement varied greatly between different haplogroups and was found to be highest in clade K. In the forensically relevant context of the minHT, the separate analysis of the DYS385 alleles had no effect on the differentiation of paternal lineages in our study. Furthermore, the amplicon lengths of 700–780 base pairs obtained in the course of the locus-discriminating approach restrict the applicability of this amplification strategy to high quality DNA samples. 相似文献
994.
Polymorphism of 18 STR loci specific to the human Y chromosome (DYS19, DYS388, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS426, DYS437, DYS438, DYS439, DYS460, GATA H4.1, DYS385 a/b, and YCAII a/b) was evaluated by means of a multiplex (octadecaplex) PCR reaction and capillary electrophoresis in a Polish population sample of 208 unrelated males. A total of 192 different haplotypes and 183 unique haplotypes were identified. The observed haplotype diversity was 0.998, while discrimination capacity was 92.3%. DYS389 was shown to be the most valuable in discrimination of similar haplotypes, whereas DYS388, DYS393, DYS426, and DYS438 did not affect the discrimination power of the multiplex.Electronic Supplementary Material Supplementary material is available for this article at . 相似文献
995.
996.
Hernando C Plaja A Català V Sarret E Egozcue J Fuster C 《Fertility and sterility》2004,82(6):1666-1671
OBJECTIVE: To characterize a complex chromosome rearrangement (CCR) previously detected by G-banding in peripheral blood lymphocytes, as 46,X,-2,-11,-22,-X,+mar 1+mar2+mar3+mar4 in a patient with primary amenorrhea. DESIGN: Case report. SETTING: University faculty of Medicine and hospital. PATIENT(S): A 36-year-old woman with primary amenorrhea. INTERVENTION(S): Fluorescence in situ hybridization (FISH). MAIN OUTCOME MEASURE(S): Use of commercially available M-FISH probe (24 colors simultaneously) and whole chromosome painting probes for chromosomes 2, 11, 22, and X to characterize the CCR. RESULT(S): The use of conventional and multiple FISH allowed the redefinition of the CCR, showing a cryptic insertion of chromosome 11 in marker 3 previously suspected by M-FISH. The combination of G-banding and FISH data revealed that four chromosomes and seven breakpoints, including 2q21, 2q31, 11q22.1, 11q22.3, 22q13.3, Xp11.21, and Xq24, were implicated in this CCR. CONCLUSION(S): This report confirms the importance of a combination of G-banding and FISH (M-FISH and conventional FISH) techniques to characterize the de novo CCR. These techniques also were useful in defining two possible critical chromosome regions, Xp11.21 and Xq24, in which genes of potential interest for a primary amenorrhea could be located. 相似文献
997.
OBJECTIVE: To characterize meiotic anomalies in infertile men by multiplex fluorescence in situ hybridization (M-FISH) and to determine whether synaptic problems affect specific bivalents or whether anomalies are random. DESIGN: Analysis of meiotic preparations with standard techniques and M-FISH. SETTING: Assisted reproduction centers and Universitat Autònoma de Barcelona. PATIENT(S): Three fertile men undergoing vasectomy, four sterile patients with oligoasthenoteratozoospermia, and one patient with a Robertsonian translocation t(13;14). INTERVENTION(S): Unilateral testicular biopsy in controls and patients with oligoasthenoteratozoospermia and collection of a semen sample from the translocation carrier. MAIN OUTCOME MEASURE(S): Identification of bivalents in metaphase I and chromosomes in metaphase II and characterization of chromosome abnormalities. RESULT(S): All bivalents in metaphase I and all chromosomes in metaphase II could be identified. In controls and in one patient with oligoasthenoteratozoospermia, meiosis was normal. Other patients with oligoasthenoteratozoospermia showed different types of anomaly: desynapsis, breaks, precocious XY separation, or cryptic reorganizations. The Robertsonian translocation t(13;14) was easily identified. CONCLUSION(S): Results confirm the high incidence of synaptic errors in oligoasthenoteratozoospermia patients. Bivalents in metaphase I and chromosomes in metaphase II were individually identifiable. Nondisjunctional errors or small reorganizations overlooked in classic meiotic preparations were identified. Synaptic anomalies seem to affect meiotic bivalents at random. 相似文献
998.
Röpke A Erbersdobler A Hammerer P Palisaar J John K Stumm M Wieacker P 《The Prostate》2004,59(1):59-68
BACKGROUND: Prostate cancer is an androgen dependent tumor. In advanced prostate cancers androgen deprivation has proved to be an effective therapy, but 25% show no response. In this study prostatectomy specimens from patients without preoperative therapy were analyzed to determine the possible mechanism of primary antiandrogen resistance. METHODS: The number of androgen receptor (AR) gene copies and X-centromeres were investigated from 80 prostate cancer specimens by FISH analysis. RESULTS: In 9 out of 80 prostate cancers additional X-chromosomes with the corresponding AR gene could be detected. Polysomy of the X-chromosome correlates with pathological classification and tumor volume. CONCLUSIONS: Additional AR genes due to polysomy of the X-chromosome are present in a subgroup of primary prostate cancers prior to antiandrogen therapy. Because the growth of prostate cancers is androgen dependent, these specimens may have an advantage in low concentrations of androgens. This may be a factor for initial antiandrogen resistance. 相似文献
999.
Comparison of the nuclear matrix protein 22 with voided urine cytology in the diagnosis of transitional cell carcinoma of the bladder 总被引:2,自引:0,他引:2
Lekili M Sener E Demir MA Temeltaş G Müezzinoğlu T Büyüksu C 《Urological research》2004,32(2):124-128
Several urinary markers for transitional cell carcinoma have been investigated, including urine cytology, bladder tumor antigen, autocrine motility factor receptor and fibrin degradation products. Unfortunately, they have poor overall sensitivity. The United States Food and Drug Administration have recently approved nuclear matrix protein (NMP 22) for the detection of occult or rapidly recurring disease after transurethral resection of bladder tumor. The objective of the current study was to assess the sensitivity of NMP 22 for the detection of bladder carcinoma, as well as to correlate the NMP 22 values with multiplicity of tumor, tumor size, configuration, stage and grade respectively. A total of 78 patients (38 with bladder cancer) provided a urine sample which was divided into appropriate aliquots for each of urine cytology and NMP 22. Comparative results demonstrate a clear superiority of NMP 22 in bladder cancer detection (52.6% vs 31.6% sensitivity), while specificity was in favor of urine cytology (100% vs 82.5%). For superficial tumors, sensitivity was 78.5% for NMP 22 and 41.6% for cytology and for invasive cancers, sensitivity was 90% for NMP 22 and 60% for cytology. Urinary NMP 22 levels were significantly correlated with tumor grade and were significantly higher in large tumors than small tumors. NMP 22 test results showed sufficient sensitivity in comparison with urine cytology for the detection of transitional cell carcinoma. However, we do not think that it is a useful tool as a substitute for endoscopic examination for the detection and surveillance in bladder cancer. 相似文献
1000.
The aim of this study was to find the correlation between serum p53 and carcinoma of the bladder and to investigate whether serum p53 protein can be used as a tumor marker for p53 gene alteration. The study included patients with carcinoma of the bladder and controls. Serum p53 protein estimation was done with an ELISA kit. There were 23 patients with superficial and 17 with invasive carcinoma. The median serum p53 was 31.5 U/ml in superficial and 41 U/ml in invasive cancer. This was significantly higher than the mean value (16.4 U/ml) of controls. Serum p53 rises in patients with carcinoma of the bladder and correlates with the grade of the disease .It can therefore be used as a tumor marker for bladder cancer. 相似文献