Comparative measurement of collagen bundle orientation by Fourier analysis and semiquantitative evaluation: reliability and agreement in Masson's trichrome, Picrosirius red and confocal microscopy techniques

Isolated chondrocytes stained with fluo 4-AM and visualized using standard confocal microscopy techniques exhibited Ca2+ transients and oscillations. Decreasing the power of the laser light decreased the percentage of cells exhibiting these Ca2+ signals. Treatment with the antioxidant ascorbate reduced the Ca2+ response, suggesting that it was mediated by light-induced release of reactive oxygen species (ROS). Cell viability 24 h after the 1-h confocal imaging period was ∼90% for cells that were neither fluorescently stained nor subjected to laser excitation. By contrast, fluorescently stained cells imaged for 1 h exhibited greatly reduced viability. Treatment with ascorbate reduced the level of cell death, suggesting that the effect was mediated by release of exogenous ROS associated with the interaction of light and the fluorochrome. Ca2+oscillations were not always associated with cell death, suggesting that separate light-sensitive pathways mediate the two processes. Light-activated Ca2+ signaling may trigger alterations in numerous cell processes and thereby represent an important and hitherto overlooked artifact in fluorescent microscopy of viable cells.

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Angiotensin II and its receptors in human endocardial endothelial cells: role in modulating intracellular calcium

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y03-046 ◽

2003 ◽

Vol 81 (3) ◽

pp. 259-266 ◽

Cited By ~ 22

Author(s):

Danielle Jacques ◽

Nelly A. Abdel Malak ◽

Sawsan Sader ◽

Claudine Perreault

Keyword(s):

Endothelial Cells ◽

Angiotensin Ii ◽

Confocal Microscopy ◽

Intracellular Calcium ◽

Fluorescence Signal ◽

Ang Ii ◽

Microscopy Technique ◽

Endocardial Endothelial Cells ◽

Microscopy Techniques ◽

Dose Dependent

he aims of the present study are to investigate the presence and distribution of angiotensin II (Ang II), as well as AT1 and AT2 receptors, in endocardial endothelial cells (EECs) and to determine if the effect of Ang II on intracellular calcium in these cells is mediated via the AT1 or the AT2 receptor. Immunofluorescence and 3D confocal microscopy techniques were used on 20-week-old fetal human EECs. Our results showed that Ang II and its receptors, the AT1 and the AT2 types, are present and exhibit a different distribution in human EECs. Ang II labelling is found throughout the cell with a fluorescence signal higher in the cytosol when compared with the nucleus. Like Ang II, the AT1 receptor fluorescence signal is also homogeneously distributed in human EECs but with a preferential labelling at the level of the nucleus, while the AT2 receptor labelling is solely present in the nucleus. Using fluo-3 and 3D confocal microscopy technique, superfusion of human EECs with increasing concentration of Ang II induced a dose-dependent sustained increase in free cytosolic and nuclear Ca2+ levels. This effect of Ang II on human EEC's intra cellular Ca2+ ([Ca2+]i) was completely prevented by losartan, an AT1 receptor antagonist. Our results suggest that Ang II, as well as AT1 and AT2 receptors, is present but differentially distributed in EECs of 20-week-old fetal human hearts, and that the AT1 receptor mediates the effects of Ang II on [Ca2+]i in these cells.Key words: angiotensin II, nuclear receptors, endocardial endothelial cells, Ang II receptors, intracellular calcium.

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The challenge of Diagnosing Common Dermatomycosis by Reflectance Confocal Microscopy

Dermatology and Dermatitis ◽

10.31579/2578-8949/085 ◽

2021 ◽

Vol 6 (3) ◽

pp. 01-07

Author(s):

Jianyun Lu ◽

Jinrong Zeng ◽

Hanyi Zhang ◽

Yue Zhang ◽

Lihua Gao ◽

...

Keyword(s):

Confocal Microscopy ◽

Fungal Infections ◽

Pityriasis Versicolor ◽

Tinea Corporis ◽

Reflectance Confocal Microscopy ◽

Fungal Culture ◽

Image Characteristics ◽

Tinea Manus ◽

Microscopy Techniques

Background: Traditional detection of fungal infections of the skin relies on microscopy techniques or fungal culture. Currently, reﬂectance confocal microscopy (RCM) has been widely applied to assist the diagnosis of commondermatomycosis with advantages of non-invasiveness, celerity, real time, and repeatability. Materials and Methods: A total of 478 clinically suspected dermatomycosis patients were enrolled in this study including 148 cases of tinea manus and pedis, 188 cases of tinea corporis and cruris and 142 cases of pityriasis versicolor. RCM examination was performed to image the lesions. Aim: This study aimed to summarize the image characteristics of in vivo RCM examination on common dermatomycosis and retrospectively evaluate its accuracy as compared with microscopy results. Furthermore, we attempted to tackle the challenges of RCM diagnosis on common dermatomycosis. Results: Based on RCM images, 231 of 478 (48.3%) patients were detected with hyphae. Among all RCM confirmed cases, 58 out of 148 (39.2%) were tinea manus and pedis, 145 out of 188 (77.1%) were tinea corporis and cruris, and 28 out of 142 (19.7%) were pityriasis versicolor. The remaining patients (51.7%) could not be diagnosed by the dermatologist according to RCM. Hyphae structures were primarily identified during diagnoses of dermatomycosis by RCM. Conclusions: RCM is a novel optical imaging technique that confers high-resolution images of fungi. RCM has certain advantages in the diagnosis of tinea manus and pedis. RCM is not suitable for the diagnosis of pityriasis versicolor.

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