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191.
WT1 levels may be a useful predictor of leukemia free survival (LFS) following treatment of acute myeloid leukemia (AML). We report a retrospective study in which levels of WT1 expression from patients with de novo AML were measured from bone marrow and peripheral blood at diagnosis, post-induction, post-consolidation and relapse. We demonstrate that higher levels of WT1 in peripheral blood at diagnosis are associated with poorer LFS independent of age and cytogenetic risk-group (n=85, p=0.028). When measured at post-consolidation, the presence of detectable WT1 is associated with poorer LFS in univariate analysis of both peripheral blood (p=0.024) and bone marrow (p=0.019). In a multivariate analysis including age and cytogenetic risk, the association remained significant for bone marrow (p=0.016) with a trend observed for peripheral blood (p=0.06). These findings have formed the basis for ongoing research.  相似文献   
192.
Polycomb repressive complex 2 (PRC2) and its core member enhancer of zeste homolog 2 (EZH2) mediate the epigenetic gene silencing mark: trimethylation of lysine 27 on histone 3 (H3K27me3). H3K27me3 is characteristic of the chromatin at genes involved in developmental regulation in undifferentiated cells. Overexpression of EZH2 has been found in several cancer types such as breast, prostate, melanoma and bladder cancer. Moreover, overexpression is associated with highly proliferative and aggressive types of breast and prostate tumors. We have analyzed the abundance of EZH2 and H3K27me3 using immunohistochemistry in two large and well-characterized breast tumor data sets encompassing more than 400 tumors. The results have been analyzed in relation to the molecular subtypes of breast tumors (basal-like, luminal A, luminal B, HER2-enriched and normal-like), as well as in subtypes defined by clinical markers (triple negative, ER+/HER2-/Ki67low, ER+/HER2-/Ki67high and HER2+), and were validated in representative breast cancer cell lines by western blot. We found significantly different expression of both EZH2 and H3K27me3 across all subtypes with high abundance of EZH2 in basal-like, triple negative and HER2-enriched tumors, and high H3K27me3 in luminal A, HER2-enriched and normal-like tumors. Intriguingly, the two markers show an inverse correlation, particularly for the basal-like and triple negative tumors. Consequently, high expression of EZH2 was associated with poor distant disease-free survival whereas high expression of H3K27me3 was associated with better survival. Additionally, none of 182 breast tumors was found to carry a previously described EZH2 mutation affecting Tyr641. Our observation that increased expression of EZH2 does not necessarily correlate with increased abundance of H3K27me3 supports the idea that EZH2 can have effects beyond epigenetic silencing of target genes in breast cancer.  相似文献   
193.

Purpose

In the prostate specific antigen (PSA) range of 4–10 ng/ml after a negative digital rectal examination, the PSA value indicates a lack of specificity with a carcinoma detection rate of roughly 20%. To improve the biopsy/carcinoma ratio, the interdisciplinary consensus recommends free PSA (fPSA) measurement. This does not take into account the pre-analysis when the cutoff value is established for biopsy indication.

Methods

In the present study, an in-patient cohort whose blood samples were immediately analysed was compared with an out-patient cohort whose sample processing was delayed by between 24 and 48 h.

Results

The in-patient cohort comprises 382 patients with 99 prostate carcinomas, the out-patient cohort 987 patients with 235 carcinomas. In the in-patient cohort a sensitivity of 90% with a cutoff value of 25% for the f/t-PSA ratios is achieved with the theoretical possibility of reducing the number of punch biopsies by 34.6%. A sensitivity of 90% in the out-patient cohort necessitates a cutoff value of 18% for the f/t-PSA ratios. The specificity is 35.3% with a possible biopsy reduction of 29.1%.

Conclusions

The cutoff values from cohorts with an immediate fPSA measurement cannot be adopted for a typical out-patient cohort whose analyses are delayed. On the contrary, an individual adjustment is necessary which corresponds to the pre-analysis.  相似文献   
194.
肛管直肠超声可用来诊断多种肛管直肠良、恶性疾病。近几年来.该技术取得了长足进步.其应用360度旋转高频(6.16MHZ)探头(焦距2.8~6.2cm),无需转动探头便可获得高清晰的肛管直肠三维结构图。位于探头远端的换能晶片向近端边旋转边移动,持续55S.可获得长约6cm的图像。这个图像是将连续的0.2mm层厚轴向切面通过容积再现技术合成的高清晰的三维数字立体图像。其拥有多个视角(同时4~6个视野).可同时观察多个解剖平面.进行低亮度、高对比度调整,可形成半透明暗腔。  相似文献   
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197.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Aus Sicht der Bundesregierung ist der One-Health-Ansatz ein wegweisender Kompass für ein inter- und transdisziplinäres...  相似文献   
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199.
Diagnosing salivary gland tumors (SGTs) through fine-needle aspiration (FNA) biopsies is challenging due to the overlapping cytomorphologic features between benign and malignant tumors. The authors developed an innovative, multiplexed cycling technology for the rapid analyses of single cells obtained from FNA that can facilitate the molecular analyses and diagnosis of SGTs. Antibodies against 29 protein markers associated with 7 SGT subtypes were validated and chemically modified via custom linker–bio-orthogonal probes (FAST). Single-cell homogenates and FNA samples were profiled by FAST cyclic imaging and computational analysis. A prediction model was generated using a training set of 151,926 cells from primary SGTs (N = 26) and validated on a separate cohort (N = 30). Companion biomarker testing, such as neurotrophic tyrosine receptor kinase (NTRK), was also assessed with the FAST technology. The FAST molecular diagnostic assay was able to distinguish between benign and malignant SGTs with an accuracy of 0.86 for single-cell homogenate samples and 0.88 for FNA samples. Profiling of multiple markers as compared to a single marker increased the diagnostic accuracy (0.82 as compared to 0.65-0.74, respectively), independent of the cell number sampled. NTRK expression was also assessed by the FAST assay, highlighting the potential therapeutic application of this technology. Application of the novel multiplexed single-cell technology facilitates rapid biomarker testing from FNA samples at low cost. The customizable and modular FAST-FNA approach has relevance to multiple pathologies and organ systems where cytologic samples are often scarce and/or indeterminate resulting in improved diagnostic workflows and timely therapeutic clinical decision-making.  相似文献   
200.
Familial Mediterranean fever (FMF), inherited in an autosomal recessive manner, is a systemic auto‐inflammatory disorder characterized by recurrent attacks of fever with peritonitis, pleuritis, synovitis and erysipeloid rash. The marenostrin‐encoding fever (MEFV) gene, located on chromosome 16p13.3, is the only gene in which mutations are currently known to cause FMF. To correlate specific genotypes with adverse phenotypes of affected populations residing in the Western United States, a retrospective case series review was conducted of all MEFV gene mutation testing completed at UCLA Clinical Molecular Diagnostic Laboratory between February 2002 and February 2012, followed by clinical chart review of all subjects who either have a single or double mutation. All 12 common mutations in the MEFV gene were analyzed and the M694V variant was found to be associated with an adverse FMF clinical outcome in the Armenian‐American population, manifested by earlier onset of disease, increased severity of disease, and renal amyloidosis.  相似文献   
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