Superresolution Fluorescence Microscopy of Platelet Subcellular Structures as a Potential Tumor Liquid Biopsy.

Blood-based tumor liquid biopsies are promising as an alternative or complement to tissue biopsies due to their noninvasiveness, convenience, and safety, and there is still a great demand for the discovery of new biomarkers for these biopsies. Here, nanoscale distribution patterns of subcellular structures in platelets, as imaged by structured illumination superresolution fluorescence microscopy, as a new type of potential biomarker for tumor liquid biopsies are presented. A standardized protocol for platelet sample preparation and developed an automated high-throughput image analysis workflow is established. The diagnostic capability based on the statistical analysis of 280 000 superresolution images of individual platelets from a variety of tumor patients, benign mass patients, and healthy volunteers (n = 206) is explored. These results suggest that the nanoscale distribution patterns of α-granules in platelets have the potential to be biomarkers for several cancers, including glioma and cervical, endometrial, and ovarian cancers, facilitating not only diagnosis but also therapeutic monitoring. This study provides a promising novel type of platelet parameter for tumor liquid biopsies at the subcellular level rather than the existing cellular or molecular level and opens up a new avenue for clinical applications of superresolution imaging techniques.

Quantitative structured illumination microscopy via a physical model-based background filtering algorithm reveals actin dynamics.

Despite the prevalence of superresolution (SR) microscopy, quantitative live-cell SR imaging that maintains the completeness of delicate structures and the linearity of fluorescence signals remains an uncharted territory. Structured illumination microscopy (SIM) is the ideal tool for live-cell SR imaging. However, it suffers from an out-of-focus background that leads to reconstruction artifacts. Previous post hoc background suppression methods are prone to human bias, fail at densely labeled structures, and are nonlinear. Here, we propose a physical model-based Background Filtering method for living cell SR imaging combined with the 2D-SIM reconstruction procedure (BF-SIM). BF-SIM helps preserve intricate and weak structures down to sub-70 nm resolution while maintaining signal linearity, which allows for the discovery of dynamic actin structures that, to the best of our knowledge, have not been previously monitored.

Pyruvic acid stress caused color attenuation by interfering with anthocyanins metabolism during alcoholic fermentation.

Anthocyanin accounts for wine color performance, while it is susceptive to saccharomyces cerevisiae, causing threatened stability. Considering pyranoanthocyanin performed better color and stability, converting anthocyanins to pyranoanthocyanins in advance during fermentation was an ideal way for color improvement. Thus, pyruvic acid (PA) as the precursor of vitisin A was applied to fermentation with cyanidin-3-O-glucoside (C3G). Results showed that PA-stress leads to a color loss associated with a decrease in C3G and cyanidin. However, the content of pyranoanthocyanins under PA stress is unvaried. LC-MS-based non-target metabolomics revealed that superfluous PA can disturb the process of glycolysis and tricarboxylic acid cycle. Importantly, 1291 molecular features were increased and 1122 were decreased under PA-stress, in which several anthocyanins derivatization and isomerization were changed, contributing to color performance. This study indicated that extra PA is unfriendly to anthocyanins during fermentation, playing an adverse effect on color, which should be avoided in wine production.

Synthesis, structural characterization, and evaluation of cyanidin-3-O-glucoside-loaded chitosan nanoparticles.

Crabapple (Malus prunifolia Willd. Borkh) is a kind of wild apples with many health benefits. However, the utilization of crabapple fruit remains scarce, due to the poor stability of C3G. In this study, C3G loaded nanoparticles were established by chitosan (CS), chitosan oligosaccharides (CSO), and carboxymethyl chitosan (CMC) united with ionic crosslinking agent γ-Polyglutamic acid (PGA) or calcium chloride (CaCl2) to improve the stability of C3G. Results showed that C3G-loaded nanoparticles were exhibited nearly spherical with homogeneous morphology. Particularly, C3G-CMC-CaCl2 nanoparticles exhibited the highest encapsulation efficiency (53.88%) and loading efficiency (5.11%) with preferable particle size (180 nm), good stability (-19 mV) and blood compatibility. C3G-CMC-CaCl2 nanoparticles also revealed the highest releasing ratio (~75%) at pH 5.3 with stability. Present study established the chemical and cell biological basis for further application of C3G-loaded nanoparticles in nutraceutical and functional food fields, extending the application of crabapple in food processing with bioactive enhancement.