Laser Scanning Confocal technique

Fluorescence of secretory structures may be seen and measured by various technique from simple luminescent microscope and complex laser scanning confocal microscope to microspectrofluorimetry described in this chapter. 

Using the freeze fracture technique, electron microscopy and laser scanning confocal microscopy, it became obvious that these gap junctional channels are arranged as a cluster of channels with about 50 channels within one disk as stated by Gourdie et al. [1990]. 

The relatively new technique of laser scanning confocal microscopy enabled the determination of the number of gap junctions within one disk to be in the order of 50 or even more [Gourdie et al., 1990] with a diameter of up to 1.3 pm/gap junction. Within the gap junction the channels themselves are arranged as parallel pipe-like structures. From freeze-fractured junctions it has been estimated that about 12.9 103 channels are located in 1 pm2 gap junction (rat right ventricular myocardium) [Chen et al., 1989]. 

Rojanasakul et al. [88] found that most of these enhancers (in particular, EDTA, digitonin, and sodium deoxycholate) increased the corneal permeability, and they may lead to severe cellular membrane damage as indicated by laser scanning confocal microscopy and electro-physiological techniques. 

Evans, A.A., and R.E. Donahue. 2008. Laser scanning confocal microscopy a potential technique for the study of lithic microwear. Journal of Archaeological Science 35 2223-2230. 

Fig. 3. Simplified diagram of the confocal components of the AC AS 570. The laser beam is expanded to provide a diffraction limited spot at the sample. A focusing lens in front of the detection system directs the fluorescence from the focal plane through an adjustable pinhole. In the bilateral laser scanning confocal microscope, a similar technique is employed with a cursor rather than a point for illumination and detection.

ROS production is a common feature in responses to environmental stress.10 It has been demonstrated that heat-shock transcription factor, HsfA2, plays a crucial role in maintaining redox balance. 1 Using a ROS-specific probe and laser scanning confocal microscopy (LCSM), ROS production could be clearly monitored in situ. 0 Here, we used a DF technique combined with LCSM imaging to detect the responses of HsfA2 mutants and wild type (WT) plants to heat stress. 

Figure 9.2 is a schematic representation of CdSe QDs dispersed in poly(hexyl methacrylate) by in situ polymerization. The polymer with long alkyl branches is expected to prevent or reduce phase separation of the QDs from the polymer matrix during polymerization. This technique resulted in the preparation of a series of QD-based nanocomposite materials for which laser scanned confocal microscopy imaging revealed a nearly uniform dispersion of nanoparticles within the polymethacrylate matrix (Fig. 9.3). Notably, the resulting macroscopic QD-polymer composites appeared to be clear and uniformly colored.

Fig.1 Schematic representing the optical pathway and image information flow of the laser scanning confocal microscopy (LSCM) technique. All principle components of generic LSCM are labeled (Redrawn in part frtnn Carl Zeiss The Confocal Laser Scanning Microscope)...

Harada et al. (2007) have prepared compatibilized blends of PLA wifli poly (butylene succinate) through addition of lysine trisisocyanate. Characterization techniques included MFR, mechanical properties, SEC, and laser scanning confocal microscopy. 

In the present chapter, we discuss the principles and techniques commonly used for observing biological surface structures, including optical microscopy (light microscopy, laser scanning confocal microscopy), electron microscopy (scanning electron microscopy, transmission electron microscopy), and scanning probe microscopy. We describe and contrast the sample preparation of each technique. Quantitative data analysis as well as the limitations of each technique is also addressed. 

Optical imaging with collinear optical coherence and confocal fluorescence microscopy (OCM-CFM). This noninvasive imaging technique combines the use of reflection confocal microscopy in tandem with optical coherence microscopy to characterize scaffolds and tissue constructs. It can probe the interior of scaffolds with the same resolution as conventional laser scanning confocal microscopy but with greater sensitivity (P). 

More advanced (and expensive) microscopy techniques are differential interference contrast microscopy and laser scanning confocal microscopy. The latter can provide precise optical sectioning so that three-dimensional images of stmctures can be recorded. 

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