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Microscope System (microscope + system)
Selected AbstractsUse of automated microscopy for the detection of disseminated tumor cells in bone marrow samplesCYTOMETRY, Issue 4 2001Elin Borgen Abstract The use of automated microscopy has reached the maturity necessary for its routine use in the clinical pathology laboratory. In the following study we compared the performance of an automated microscope system (MDSÔ) with manual method for the detection and analysis of disseminated tumor cells present in bone marrow preparations from breast carcinoma patients. The MDS System detected rare disseminated tumor cells among bone marrow mononuclear cells with higher sensitivity than standard manual microscopy. Automated microscopy also proved to be a method of high reproducibility and precision, the advantage of which was clearly illustrated by problems of variability in manual screening. Accumulated results from two pathologists who had screened 120 clinical slides from breast cancer patients both by manual microscopy and by use of the MDS System revealed only two (3.8%) missed by the automatic procedure, whereas as many as 20 out of 52 positive samples (38%) were missed by manual screening. Cytometry (Comm. Clin. Cytometry) 46:215,221, 2001. © 2001 Wiley-Liss, Inc. [source] Involvement of Cdc42 and Rac small G proteins in invadopodia formation of RPMI7951 cellsGENES TO CELLS, Issue 12 2003Hirokazu Nakahara Background:, Invadopodia are membrane protrusions into the extracellular matrix by aggressive tumour cells. These structures are associated with sites of matrix degradation and invasiveness of malignant tumour cells in an in vitro fibronectin degradation/invasion assay. The Rho family small G proteins, consisting of the Rho, Rac and Cdc42 subfamilies, are implicated in various cell functions, such as cell shape change, adhesion, and motility, through reorganization of the actin cytoskeleton. We studied the roles of the Rho family small G proteins in invadopodia formation. Results:, We first demonstrated that invadopodia of RPMI7951 human melanoma cells extended into the matrix substratum on a vertical view using a laser scanning confocal microscope system. We confirmed that invadopodia were rich in actin filaments (F-actin) and visualized clearly with F-actin staining on a vertical view as well as on a horizontal view. We then studied the roles of Rho, Rac, and Cdc42 in invasiveness of the same cell line. In the in vitro fibronectin degradation/invasion assay, a dominant active mutant of Cdc42 enhanced dot-like degradation, whereas a dominant active mutant of Rac enhanced diffuse-type degradation. Furthermore, frabin, a GDP/GTP exchange protein for Cdc42 with F-actin-binding activity, enhanced both dot-like and diffuse-type degradation. However, a dominant active mutant of Rho did not affect the fibronectin degradation. Moreover, inhibition of phosphatidylinositol-3 kinase (PI3K) disrupted the Rac and Cdc42-dependent actin structures and blocked the fibronectin degradation. Conclusion:, These results suggest that Cdc42 and Rac play important roles in fibronectin degradation and invasiveness in a coordinate manner through the frabin-Cdc42/Rac-PI3K signalling pathway. [source] Spectral imaging fluorescence microscopyGENES TO CELLS, Issue 9 2002Tokuko Haraguchi The spectral resolution of fluorescence microscope images in living cells is achieved by using a confocal laser scanning microscope equipped with grating optics. This capability of temporal and spectral resolution is especially useful for detecting spectral changes of a fluorescent dye; for example, those associated with fluorescence resonance energy transfer (FRET). Using the spectral imaging fluorescence microscope system, it is also possible to resolve emitted signals from fluorescent dyes that have spectra largely overlapping with each other, such as fluorescein isothiocyanate (FITC) and green fluorescent protein (GFP). [source] Automatic annular laser trapping: a system for high-throughput sperm analysis and sortingJOURNAL OF BIOPHOTONICS, Issue 3 2009Linda Shi Abstract An automatic microscope system is designed to study the response of sperm motility to an annular laser trap. A continuous annular laser trap provides a parallel way to analyze and sort sperm based on their motility and to study the effects of laser radiation, optical force and external obstacles. In the described automatic microscope system, the phase contrast images of swimming sperm are digitized to the computer at video rates. The microscope stage is controlled in real-time to relocate the sperm of interest to the annular trap with a normal or tangential entering angle. The sperm is continuously tracked and the swimming behavior is identified. Using this system, parallel sorting on human and gorilla sperm are achieved and threshold power levels separating the "fast" group and the "slow" group are compared for those two species. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A white light confocal microscope for spectrally resolved multidimensional imagingJOURNAL OF MICROSCOPY, Issue 3 2007J. H. FRANK Summary Spectrofluorometric imaging microscopy is demonstrated in a confocal microscope using a supercontinuum laser as an excitation source and a custom-built prism spectrometer for detection. This microscope system provides confocal imaging with spectrally resolved fluorescence excitation and detection from 450 to 700 nm. The supercontinuum laser provides a broad spectrum light source and is coupled with an acousto-optic tunable filter to provide continuously tunable fluorescence excitation with a 1-nm bandwidth. Eight different excitation wavelengths can be simultaneously selected. The prism spectrometer provides spectrally resolved detection with sensitivity comparable to a standard confocal system. This new microscope system enables optimal access to a multitude of fluorophores and provides fluorescence excitation and emission spectra for each location in a 3D confocal image. The speed of the spectral scans is suitable for spectrofluorometric imaging of live cells. Effects of chromatic aberration are modest and do not significantly limit the spatial resolution of the confocal measurements. [source] X-ray imaging of various biological samples using a phase-contrast hard X-ray microscopeMICROSCOPY RESEARCH AND TECHNIQUE, Issue 9 2008Guk Bae Kim Abstract In this study, we visualized the internal structures of various bio-samples and found the optimum conditions of test samples for the 7 keV hard X-ray microscope of the Pohang light source. From the captured X-ray images, we could observe the intercellular and intracellular structures of dehydrated human cells and mouse tumor tissues without using any staining materials in a spatial resolution better than 100 nm. The metastasized lung tissue, which was several tens of micrometers in thickness, was found to be very well suited to this hard X-ray microscope system, because it is nearly impossible to observe such a nontransparent and thick sample with a high spatial resolution better than 100 nm using any microscopes such as a soft X-ray microscope, an optical microscope, or an electron microscope. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc. [source] Characterization of ZAG protein expression in prostate cancer using a semi-automated microscope systemTHE PROSTATE, Issue 10 2006Aurelien Descazeaud Abstract OBJECTIVE Zinc-alpha-2-glycoprotein 1 (ZAG) is a 41-kD secreted protein that is known to stimulate lipid degradation in adipocytes. The aim of this study was to determine how ZAG protein expression is associated with prostate cancer (PCa). MATERIALS AND METHODS An immunohistochemistry analysis was performed on a 227 PCa tissue microarray cases. ZAG protein expression was assessed using a semi-automated cellular image analysis system. RESULTS ZAG expression was associated with tumor stage (pT2,>,pT3,>,metastasis cases, P,<,0.001), and was inversely associated with Gleason score on pathology (P,=,0.01). ZAG intensity was predictive of biochemical recurrence (P,=,0.002). On multivariate analysis including pT2 patients, the predictive factors of biochemical recurrence were ZAG expression (P,=,0.016), Gleason score (P,=,0.011), and surgical margin status (P,=,0.047). CONCLUSIONS This study characterized ZAG protein expression in PCa using a semi-automated system. ZAG expression level found to have an independent prognostic value for pT2 patients. Prostate 66: 1037,1043, 2006. © 2006 Wiley-Liss, Inc. [source] Investigations of thermotropic phase behavior of newly developed synthetic PEGylated lipids using Raman spectro-microscopyBIOPOLYMERS, Issue 11 2008Rajan K. Bista Abstract In this article, a temperature-controlled Raman spectro-microscopic technique has been utilized to detect and analyze the phase behaviors of two newly developed synthetic PEGylated lipids trademarked as QuSomesÔ, which spontaneously form liposomes upon hydration in contrast to conventional lipids. The amphiphiles considered in this study differ in their hydrophobic hydrocarbon chain length and contain different units of polyethylene glycol (PEG) hydrophilic headgroups. Raman spectra of these new artificial lipids have been recorded in the spectral range of 500,3100 cm,1 by using a Raman microscope system in conjunction with a temperature-controlled sample holder. The gel to liquid phase transitions of the sample lipids composed of pure 1,2-dimyristoyl- rac -glycerol-3-dodecaethylene glycol (GDM-12) and 1,2-distearoyl- rac -glycerol-3-triicosaethylene glycol (GDS-23) have been revealed by plotting peak intensity ratios in the CH stretching region as a function of temperature. From this study, we have found that the main phase transitions occur at a temperature of ,5.2 and 21.2°C for pure GDM-12 and GDS-23, respectively. Furthermore, the lipid GDS-23 also shows a postphase transition temperature at 33.6°C. To verify our results, differential scanning calorimetry (DSC) experiments have been conducted and the results are found to be in an excellent agreement with Raman scattering data. This important information may find application in various studies including the development of lipid-based novel substances and drug delivery systems. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 1012,1020, 2008. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] | |||||||||||||