Low-frequency fluctuations in fMRI data are believed to reflect synchronous and spontaneous fluctuations in neuronal networks. A study by Fox et al. in this issue of Neuron shows that these spontaneous fluctuations in...
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Low-frequency fluctuations in fMRI data are believed to reflect synchronous and spontaneous fluctuations in neuronal networks. A study by Fox et al. in this issue of Neuron shows that these spontaneous fluctuations in the motor cortex can account for significant trial-to-trial variations in both the fMRI response and behavior.
The formation of a metaphase spindle, a bipolar microtubule array with centrally aligned chromosomes, is a prerequisite for the faithful segregation of a cell's genetic material. Using a full-genome RNA interferen...
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The formation of a metaphase spindle, a bipolar microtubule array with centrally aligned chromosomes, is a prerequisite for the faithful segregation of a cell's genetic material. Using a full-genome RNA interference screen of Drosophila S2 cells, we identified about 200 genes that contribute to spindle assembly, more than half of which were unexpected. The screen, in combination with a variety of secondary assays, led to new insights into how spindle microtubules are generated;how centrosomes are positioned;and how centrioles, centrosomes, and kinetochores are assembled.
Objective: To measure accuracy and reliability of the computer-based Retinal image Multiscale Analysis (RISA) system compared with those of recognized retinopathy of prematurity (ROP) experts, for plus disease diagnos...
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Objectives. The preoperative prediction of the likelihood of positive surgical margins (+SMs) at radical retropubic prostatectomy (RRP) may be useful for counseling and determining the surgical approach. The aim of th...
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Objectives. The preoperative prediction of the likelihood of positive surgical margins (+SMs) at radical retropubic prostatectomy (RRP) may be useful for counseling and determining the surgical approach. The aim of this study was to assess the additional value of digital image analysis (DIA) of ploidy and proliferation on needle biopsies, in addition to the known preoperative predictors of +SMs at RRP. Methods. We identified 454 patients treated by RRP at our institution from 1995 to 1998 for prostate cancer verified by transrectal ultrasound-guided biopsy, with a specimen adequate for DIA. Patients receiving preoperative hormonal therapy were excluded. The clinical features, transrectal ultrasound-guided biopsy findings, and DIA evaluation of MIB-I immunostaining and DNA ploidy were assessed in a multivariate logistic regression model to predict for +SMs at RRP. Results. The mean +/- SD age at treatment was 64.5 +/- 6.5 years, the percentage of positive cores was 40.4% +/- 24.3%, the median prostate-specific antigen level was 6.3 ng/mL (range 0.6 to 112.0), median biopsy Gleason score was 6 (range 4 to 9), and median percentage of diploid nuclei was 67% (range 0% to 100%). Of the 454 patients, 185 (40.7%) had +SMs;this finding was time dependent (1995 to 1996, 45% and 1997 to 1998, 31%;P = 0.004). Univariately, preoperative prostate-specific antigen, biopsy Gleason score, extent of cancer on biopsy, MIB-1 expression, percentage of diploid or nondiploid nuclei, and year of surgery were predictive for +SMs. On multivariate analysis, the preoperative prostate-specific antigen level, biopsy Gleason score, percentage of positive cores, and year of surgery remained significant. Conclusions. The results of our study have shown that the likelihood of +SMs at RRP is best predicted on the basis of conventional prognostic factors. The DIA features of needle biopsies did not provide additional predictive power.
O-6-alkylguanine-DNA alkyltransferase (AGT) fusion proteins can be specifically and covalently labeled with fluorescent O-6-benzylguanine (O-6-BG) derivatives for multicolor live cell imaging approaches. Here, we char...
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O-6-alkylguanine-DNA alkyltransferase (AGT) fusion proteins can be specifically and covalently labeled with fluorescent O-6-benzylguanine (O-6-BG) derivatives for multicolor live cell imaging approaches. Here, we characterize several new BG fluorophores suitable for in vivo AGT labeling that display fluorescence emission maxima covering the visible spectrum from 472 to 673 nm, thereby extending the spectral limits set by fluorescent proteins. We show that the photostability of the cell-permeable dyes BG Rhodamine Green (BG505) and CP tetramethylrhodamine (CP-TMR) is in the range of enhanced green fluorescent protein (EGFP) and monomeric red fluorescent protein (mRFP), and that BG diethylaminomethyl coumarin (BGDEAC) a derivative of coumarin, is even more stable than enhanced cyan fluorescent protein (ECFP). Due to the increasing number of new BG derivatives with interesting fluorescence properties, such as far-red emission, fluorescence labeling of AGT fusion proteins is becoming a versatile alternative to existing live cell imaging approaches.
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