Applied Microscopy最新文献

Nanotopographic control of cell behavior offers great potential in designing biomimetic scaffolds for cell therapy. However, the behavior of cells on different nanotopographies is not fully understood. In this study, we investigated the effect of nanostructures on human adipose-derived stem cells (ASCs) by directly comparing nanopillar and nanopit arrays. Morphological changes, cell viability and early osteogenic differentiation of ASCs have been analyzed on the nanostructures. Nanopit arrays were found to increase cell areas and promote early osteogenic differentiation more than nanopillar arrays. Analysis of focal adhesion (FA) formation indicated a larger increase in total area as well as the number of FAs during cell spreading on nanopit arrays. The maturation of FA is related to cellular traction forces, which are known to stimulate osteogenic induction through the RhoA-ROCK pathway. We conclude that ASCs can spread more on the nanopit array than on the nanopillar array due to the presence of continuous adhesive paths on the nanopit array, which is associated with increased expression of RUNX2 as an early osteogenic marker. Our results suggest that a connected path in nanopit arrays plays a critical role in controlling stem cell behavior compared to nanopillar arrays. A comparative understanding of nanostructures can provide a guideline for designing an artificial substrate for osteogenesis and tissue engineering.

The effective method for eliminating the Moiré fringes in the MC nanoprecipitates in the austenite matrix was studied. Considering the dynamic diffraction between the matrix and precipitate, the spots originating from the Moiré pattern were selected in the fast Fourier transform (FFT) pattern. The Moiré fringe image was extracted by performing inverse FFT(IFFT) of the selected spots. Subtracting the Moiré fringe contribution from the original image intensity reveals the veiled lattice fringes of MC carbide in the austenite matrix. The image was compared and discussed with the IFFT image of the direct selection of the matrix + MC FFT patterns. The suggested method was applied to strain measurement in the MC carbide-containing area using the geometrical phase analysis. Compared with the result obtained from the raw image containing Moiré fringes, the applied method shows artifact-free strain distribution in the MC carbide. The process was applied to the inclined twin interface in BCC steel. The lattice fringe in the overlapping area shows a more detailed lattice feature. This novel study sheds light on the veiled crystal structure and strain distribution under various conditions where more than two lattice fringes overlap.

We established a correlative workflow combining X-ray microscopy (XRM) and transmission electron microscopy (TEM) to investigate the ultrastructure of zebrafish neuromasts. Zebrafish tissues were processed using conventional TEM embedding protocols and first imaged with XRM to obtain three-dimensional information and to localize the neuromast within resin blocks. The XRM previews enabled accurate trimming and rapid identification of target regions, reducing the need for repeated semi-thin sectioning and toluidine blue staining. Subsequent TEM analysis revealed ultrastructural details including cell-to-cell contacts and organelle morphology. Our study demonstrates that integration of XRM with TEM increases efficiency, minimizes tissue loss, and improves orientation accuracy for ultrastructural analysis. This correlative approach provides a valuable workflow for volume electron microscopy, applicable to the observation of the neuromast and various other tissues.

Release of prosthesis debris at the tissue-implant interface is a major cause of aseptic loosening, a phenomenon that requires premature replacement of the prosthesis. The main objective of this paper is to propose a step-structured modus operandi for a reliable scanning electron microscopy (SEM) analysis of debris released from prostheses into the surrounding tissues. Following a proven methodology for the analysis of this wear debris would allow research and hospital laboratories to reduce time and obtain results associated with a common protocol and consequently, more comparable results. For developing the methodology, we chose the clinical case of a hip prosthetic revision, in which a Cr-Co head misalignment caused the wearing out of the polyethylene acetabular insert and a partial wear of the Ti-6Al-4 V acetabular cup. Samples of periprosthetic tissues, after being partially digested in a KOH basic solution, were investigated in vivo and in situ with SEM observations and Energy Dispersive X-rays Spectroscopy (EDXS) analyses. Although developed from a specific case study, this methodology is compatible and applicable to other standard cases as well. Regarding the set of samples we selected, a complete set of micro- and nano-structural analysis, compositional spectra and high-resolution images have been acquired, showing the morphology of the debris involved, and the agglomeration phenomena occurring in the tissue. The proposed protocol complements previous studies on tribological phenomena, underlying debris production at the tissue-prosthesis interface, best digestion techniques for fragment isolation, and nanotoxicology.

Electron ptychography has emerged as a powerful computational imaging technique using four-dimensional scanning transmission electron microscopy, greatly exceeding the resolution limits of conventional electron microscopes by quantitative phase retrieval. This paper presents recent algorithmic developments and technological requirements for detectors used in electron ptychography, as well as applications in different fields of nanoscience. The application range covers high-resolution imaging of beam-sensitive specimens, light element detection, and three-dimensional reconstruction, making electron ptychography a versatile technique for materials characterization.

This study investigated the anatomy and histology of the olfactory organ of the Korean amur goby Rhinogobius brunneus from Jeonjucheon stream. This species lives in shallow, stagnant, and intermittently low-oxygenated streams, reservoirs, and ponds affected by seasonal rainfall. Anatomically, its olfactory organ consisted of a short tubular anterior nostril, a posterior nostril, a single longitudinal lamella, and two accessory nasal sacs (ethmoidal and lacrymal sacs). Its single lamella structure resembles other gobiid fishes with a simplified olfactory surface. Histologically, the sensory epithelium comprised olfactory receptor neurons, supporting cells, and basal cells, while the non-sensory epithelium contained stratified epithelial cells, basal cells, and mucous cells. In particular, the mucous cells stained intensely red with Hematoxylin and eosin and Masson’s trichrome, indicating proteinaceous granular mucins rich in glycoproteins; such secretions likely protect the epithelium against particles, toxins, and low-oxygenated freshwater. Overall, the goby’s olfactory organ exhibits traits uniquely adapted to stagnant and hypoxic conditions.

Two-dimensional (2D) van der Waals materials possess structural degrees of freedom that set them apart from conventional bulk crystals and strongly influence their physical properties. Such freedom, enabled by the weak interlayer bonding, permits stacking, twisting, and lateral sliding of layers, leading to structural variations such as out-of-plane corrugations, layer-number–dependent electronic and optical responses, and interlayer registry variations that produce stacking domains with distinct functionalities. Capturing and understanding these variations is essential for linking structure to function. Transmission electron microscopy (TEM) offers complementary approaches for this purpose: electron diffraction provides quantitative crystallographic fingerprints, while dark-field (DF) imaging translates selected diffraction information into spatial maps of local structure. When combined, these techniques can resolve complex structural modulations across multiple length scales and under diverse experimental conditions. Recent advances have extended diffraction and DF imaging into in-situ and operando regimes, enabling real-time observation of domain reconfiguration, phase transitions, and polarization switching under external stimuli. This review discusses how these methods are applied to 2D van der Waals materials to reveal structural degrees of freedom and illustrates their unique capability to directly connect structural evolution to functional behavior.

Smart microscopy is a new imaging approach that involves rapid imaging, prediction of important subregions, then selective re-imaging. This approach has been validated in reducing imaging beam time in electron microscopy connectomics, but the speedup depends on various imaging workflow parameters. Here we present the first runtime analysis of traditional vs. smart microscopy and show how these parameters can magnify, or diminish potential time savings. We provide a GUI application that calculates the theoretical time savings of smart microscopy from user input parameters describing their imaging workflow. Finally, we measure end-to-end runtime of SmartEM acquisition on an electron microscope to demonstrate two strategies for faster acquisition: mixed-precision neural networks and parallelization of microscope and support computer operations.

The non-sticky spiral silk, which typically serves as a temporary structural component in most orb-weaving spiders, functions as a permanent scaffold in the golden orb-web spider (Trichonephila clavata). Composed of double strands approximately 4 μm in diameter, the non-sticky spiral forms robust extended junctions exceeding 200 μm in radius. The muscular cell layer observed within the pyriform gland facilitates the active extrusion of pyriform fibers and cement, enabling efficient wrapping at the junctions. These robust junctions stand in stark contrast to the loose, droplet-mediated adhesion seen in sticky spirals, allowing the non-sticky spiral to enhance web stability and effectively prevent damage expansion. Furthermore, the non-sticky spiral plays an important role in localized web repair by replicating the original web's loop patterns to restore damaged areas. These findings suggest that the non-sticky spiral stabilizes the wide intervals between radii in the lower hub region, providing enhanced resistance to external forces and repairing structural damages. The results also demonstrate the evolutionary significance of utilizing non-sticky spiral as a permanent component, facilitating the construction and maintenance of large, densely structured orb webs.