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Abdelsayed, V.

Publications and source records attributed to Abdelsayed, V..

2 recordsLinked to original sources

Advanced Optical Microscopy Reveals Spatio-Temporal Dynamics of Cervix Remodeling during Gestation

Collagen remodeling in the uterine cervix is a vital process in pregnancy that allows for timely fetal delivery, yet its spatio-temporal details are still not fully understood. In this study, we measured collagen reorganization at different stages of murine gestation and at various cervical depths. We used polarization-resolved Second Harmonic Generation microscopy to specifically detect fibrillar collagen and assess its orientation with sub-micrometer resolution. We imaged large cervical areas using automated mosaicking and implemented an analysis pipeline that showed significant region-dependent changes in collagen quantity, porosity, and orientation disorder. Notably, we found that collagen disorganization begins in the lower cervix at gestation day 12 and extends throughout the entire cervix by day 15. Additionally, we demonstrated that the temporal dynamics of disorganization, without spatial sensitivity, can also be tracked using Mueller Matrix imaging, which is a clinically deployable method. These findings should improve understanding and diagnosis of gestation-related issues such as premature birth.

biophysics↗

An Optimized Buffer for Repeatable Multicolor STORM

STORM microscopy is one of the most popular method of super-resolution microscopy, due to moderate requirements on the optical setup, and high achievable resolution. However, since its inception more than 15 years ago, protocols have barely evolved, and despite some recent progress, multicolor imaging can still be complex without the right equipment. We decided to optimize the buffer composition to improve the blinking of the most popular red dye CF-568 while maintaining good performance for far-red fluorophores such as Alexa-647 using the concentration of three chemicals and the pH as 4 optimization parameters. We developed a simple, cheap and stable buffer, that can be stored several weeks and frozen for longer term storage that allow high quality 3-color STORM imaging. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=184 SRC="FIGDIR/small/491818v2_ufig1.gif" ALT="Figure 1"> View larger version (136K): org.highwire.dtl.DTLVardef@375943org.highwire.dtl.DTLVardef@1c57e71org.highwire.dtl.DTLVardef@f05fe3org.highwire.dtl.DTLVardef@1274e4f_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗