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61.
Estrogen receptor (ER) expression was investigated by ER-immunocytochemical assay (ICA) and the dextran coated charcoal (DCC) method in 10 recurrent or primary-advanced breast cancer patients treated with endocrine or chmmo-endocrine therapy. In 6 of these 10 patients, ER was examined both before and after treatments by the 2 methods. ER contents measured by the DCC method were found to be decreased after treatments, however, no change in the immunoreactivities of ER-ICA was observed. In the remaining 4 patients, the ER of new lesions refractory to endocrine or chemo-endocrine therapy was examined. ER status was determined as negative in 3 of the 4 patients by the DCC method, whereas by ER-ICA, the proportion of ER stained cells was about 70 per cent, those cells being diffusely distributed in the section. A discrepancy between ER-ICA and the DCC method was thus demonstrated in breast cancer patients treated by endocrine therapy.  相似文献   
62.
The recently described DNA replication-based mechanisms of fork stalling and template switching (FoSTeS) and microhomology-mediated break-induced replication (MMBIR) were previously shown to catalyze complex exonic, genic and genomic rearrangements. By analyzing a large number of isochromosomes of the long arm of chromosome X (i(Xq)), using whole-genome tiling path array comparative genomic hybridization (aCGH), ultra-high resolution targeted aCGH and sequencing, we provide evidence that the FoSTeS and MMBIR mechanisms can generate large-scale gross chromosomal rearrangements leading to the deletion and duplication of entire chromosome arms, thus suggesting an important role for DNA replication-based mechanisms in both the development of genomic disorders and cancer. Furthermore, we elucidate the mechanisms of dicentric i(Xq) (idic(Xq)) formation and show that most idic(Xq) chromosomes result from non-allelic homologous recombination between palindromic low copy repeats and highly homologous palindromic LINE elements. We also show that non-recurrent-breakpoint idic(Xq) chromosomes have microhomology-associated breakpoint junctions and are likely catalyzed by microhomology-mediated replication-dependent recombination mechanisms such as FoSTeS and MMBIR. Finally, we stress the role of the proximal Xp region as a chromosomal rearrangement hotspot.  相似文献   
63.
OBJECTIVE: In patients with perforated peptic ulcer (PPU) the convergence between the high eradication rate of Helicobacter pylori infection and low rates of ulcer relapse after treatment has been associated with reinfection by non-virulent strains. The objective of this study was to evaluate the persistence of infection by virulent H. pylori strains and ulcer recurrence in 33 patients with PPU one year after surgery and antimicrobial treatment. MATERIAL AND METHODS: The histological evaluation and molecular detection of H. pylori cagA and ureA genes, vacA allelic types and the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses of the glmM gene products from antral mucosa specimens were performed initially, 2-5 months and 1 year after therapy. RESULTS: The density of H. pylori colonization was temporarily decreased (p<0.05) 2-5 months after therapy. After one year, complete eradication was achieved in only 7 patients (23%) at histological examination and recurrent ulcers were found in 3/33 (9%) patients. The vacA s1a allelic type of cagA-positive strains persisted in 19/33 (58%) PPU patients with identical PCR-RFLP fingerprints in 8/9 (89%) of the patients. CONCLUSIONS: In PPU patients with a low eradication rate of H. pylori infection after surgical and antimicrobial treatment, the frequent recrudescence of the infection is mostly caused by the persisting virulent strains of the cagA and vacA s1a subtypes. In the 1-year follow-up period the recurrent ulceration can be postponed just by the lowered colonization density of H. pylori after eradicative therapy.  相似文献   
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65.
A liquid chromatographic tandem mass spectroscopy method for the quantification of artemisinin in human heparinised plasma has been developed and validated. The method uses Oasis HLB™ μ-elution solid phase extraction 96-well plates to facilitate a high throughput of 192 samples a day. Artesunate (internal standard) in a plasma–water solution was added to plasma (50 μL) before solid phase extraction. Artemisinin and its internal standard artesunate were analysed by liquid chromatography and MS/MS detection on a Hypersil Gold C18 (100 mm × 2.1 mm, 5 μm) column using a mobile phase containing acetonitrile–ammonium acetate 10 mM pH 3.5 (50:50, v/v) at a flow rate of 0.5 mL/min. The method has been validated according to published FDA guidelines and showed excellent performance. The within-day, between-day and total precisions expressed as R.S.D., were lower than 8% at all tested quality control levels including the upper and lower limit of quantification. The limit of detection was 0.257 ng/mL for artemisinin and the calibration range was 1.03–762 ng/mL using 50 μL plasma. The method was free from matrix effects as demonstrated both graphically and quantitatively.  相似文献   
66.
We conducted a genome-wide association study of 3090 sporadic prostate cancer patients and controls using the Affymetrix 10 000 SNP GeneChip. Initial screening of 40 prostate cancer cases and 40 non-cancer controls revealed 237 SNPs to be associated with prostate cancer (P<0.05). Among these SNPs, 33 were selected for further association analysis of 2069 men who had undergone a cancer-screening prostate biopsy. Results identified five loci as being significantly associated with increased prostate cancer risk in this larger sample (rs 1930293, OR=1.7, P=0.03; rs 717809-2p12, OR=1.3, P=0.03; rs 494770-4q34, OR=1.3, P=0.01; rs 2348763-7p21, OR=1.5, P=0.01; rs 1552895-9p22, OR=1.5, P=0.002). To validate these association data, 61 additional HapMap tagSNPs spanning the latter five loci were genotyped in this subject cohort and an additional 1021 men (total subject number=3090). This analysis revealed tag SNP rs 4568789 (chromosome 1q25) and tag SNP rs 13225697 (chromosome 7p21) to be significantly associated with prostate cancer (P-values 0.009 and 0.008, respectively). Haplotype analysis revealed significant associations of prostate cancer with two allele risk haplotypes on both chromosome 1q25 (adjusted OR of 2.7 for prostate cancer, P=0.0003) and chromosome 7p21 (adjusted OR of 1.3, P=0.0004). As linkage data have identified a putative prostate cancer gene on chromosome 1q25 (HPC1), and microarray data have revealed the ETV1 oncogene to be overexpressed in prostate cancer tissue, it appears that chromosome 1q25 and 7p21 may be sites of gene variants conferring risk for sporadic and inherited forms of prostate cancer.  相似文献   
67.
Neoadjuvant chemotherapy for breast cancer has achieved a higher response rate with the combination of anthracycline and taxane. Molecular targeted agents, such as trastuzumab, are expected to enhance the effectiveness of treatment. The main objectives of neoadjuvant chemotherapy are to reduce tumor size, increase breast conserving rate, identify treatment response, adjust the following treatment strategy, and develop a new treatment using biological specimens. Recently, there has been an increasing demand to provide a tailored treatment in neoadjuvant chemotherapy with establishment of genetic testing for biological markers and adjustment of therapeutic strategy following identification of the early treatment response. We reviewed recent advances in neoadjuvant chemotherapy for breast cancer.  相似文献   
68.
Recent studies have demonstrated that tegafur-uracil (UFT) is useful for the adjuvant treatment of various types of cancers. To determine whether nucleoside metabolizing enzymes could be used to predict the response to UFT treatment in women with primary breast cancer, we retrospectively analyzed archived tumor tissue samples obtained from the 3rd Adjuvant Chemo-Endocrine Therapy for Breast Cancer (ACETBC) study, in which adjuvant treatment with tamoxifen (TAM) plus UFT for 2 years was compared with TAM alone for 2 years. Samples of tumor tissue were obtained from 192 premenopausal women with node-positive invasive breast cancer. The tissue samples were examined immunohistochemically to study the expression of thymidylate synthase (TS), thymidine phosphorylase (TP), and dihydropyrimidine dehydrogenase (DPD), as well as the expression of Her2 and p53. In patients with TS-positive tumors, the risk of relapse was significantly lower in the tamoxifen plus UFT group than in the tamoxifen alone group. After 2 years, however, there was a trend towards a decrease in the relative predictive value (RPV) of TS with time. No relationship to outcome was detected for TP or DPD. Expression of Her2 or p53 was a significant prognostic indicator in the tamoxifen alone group. TS, but not TP or DPD, may be a useful predictor of response to UFT therapy. After 2 years, the RPV of TS decreased with time, suggesting that 2 years of treatment with oral fluorouracil derivatives may be inadequate. Further studies are required to investigate this possibility.  相似文献   
69.
Anti-epiligrin cicatricial pemphigoid is an autoimmune subepithelial blistering disorder of mucous membranes and skin. By immunoblot analyses, sera of most patients with antiepiligrin cicatricial pemphigoid have been shown to react specifically with the alpha3 chain of laminin 5. We describe the first patient with anti-epiligrin cicatricial pemphigoid in whom circulating IgG autoantibodies directed against the beta3 and gamma2-chains of laminin 5 were detected. Treatment with oral prednisolone was beneficial in controlling the disease.  相似文献   
70.
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