Size and Surface Properties of Functionalized Organosilica Particles Impact Cell-Particle Interactions Including Mitochondrial Activity.

Understanding of the interactions between macrophages and multifunctional nanoparticles is important for development of novel macrophage-based immunotherapies. Here, we investigated the effects of fluorescent thiol-organosilica particle size and surface properties on cell-particle interactions, including mitochondrial activity, using the mouse macrophage cell line J774A.1.

Histological study on the reginal difference in the localization of mucosal enteric glial cells and their sheath structure in the rat intestine.

The present study aimed to histologically clarify the regional specificity of the mucosal enteric glial cells (mEGCs) in the rat intestine with serial block-face scanning electron microscopy (SBF-SEM). SBF-SEM analysis with the ileum, the cecum and the descending colon revealed that mEGC nuclei were more abundant in the data stacks from the apical portion of the villus and the lateral portion of the crypt of the ileum. mEGCs exhibited a high rate of coverage over the nerve bundle around the lateral portion of the ileal crypt, but showed an extremely low level of coverage in the luminal portion of the cecum.

Analysis of cell-nanoparticle interactions and imaging of labeled cells showing barcorded endosomes using fluorescent thiol-organosilica nanoparticles surface-functionalized with polyethyleneimine.

Biomedical imaging using cell labeling is an important technique to visualize cell dynamics in the body. To label cells, thiol-organosilica nanoparticles (thiol-OS) containing fluorescein (thiol-OS/Flu) and rhodamine B (thiol-OS/Rho) were surface-functionalized with polyethyleneimine (PEI) (OS/Flu-PEI and OS/Rho-PEI) with 4 molecular weights (MWs). We hypothesized PEI structures such as brush, bent brush, bent lie-down, and coiled types on the surface depending on MWs based on dynamic light scattering and thermal gravimetric analyses.

Differences in interaction lead to the formation of different types of insulin amyloid.

Insulin balls, localized insulin amyloids formed at the site of repeated insulin injections in patients with diabetes, cause poor glycemic control and cytotoxicity. Our previous study has shown that insulin forms two types of amyloids; toxic amyloid formed from the intact insulin ((i)-amyloid) and less-toxic amyloid formed in the presence of the reducing reagent TCEP ((r)-amyloid), suggesting insulin amyloid polymorphism. However, the differences in the formation mechanism and cytotoxicity expression are still unclear.

Correlative light and electron microscopy of poly(ʟ-lactic acid) spherulites for fast morphological measurements using a convolutional neural network.

Polarized optical microscopy (POM) and transmission electron microscopy (TEM) are widely used for imaging polymer spherulite structures. TEM provides nanometer resolution to image small spherulites of sub-micrometer in diameter, while POM is more suitable for observing large spherulites. However, high-resolution images with a large field of view are challenging to achieve due to the deformations of ultrathin sectioned samples used for TEM observations.

Ultrastructural and phenotypical diversity of macrophages in the rat ileal mucosa.

Several types of macrophages have been reported in the intestinal mucosa, but their histological localization remains ambiguous. Here, we obtained detailed information about ultrastructural and phenotypical diversity of macrophage-like cells (MLCs) in the rat ileal mucosa using immunofluorescent analysis and serial block-face scanning electron microscopy (SBF-SEM). The results revealed that the cells immunopositive for CD68, the pan-macrophage marker, included CD163CD4, CD163CD4, and CD163CD4 cells in the lamina propria (LP) of the intestinal villus and around the crypt.

Membranous Structures Directly Come in Contact With p62/SQSTM1 Bodies.

During autophagy, autophagosomes are formed to engulf cytoplasmic contents. p62/SQSTM-1 is an autophagic adaptor protein that forms p62 bodies. A unique feature of p62 bodies is that they seem to directly associate with membranous structures.

Three-dimensional analysis of neural connectivity with cells in rat ileal mucosa by serial block-face scanning electron microscopy.

The comprehensive targets of innervation in the intestinal mucosa are unknown, partly because of the diversity of cell types and the complexity of the neural circuits. Herein, we investigated the comprehensive targets of neural connectivity and analyzed the precise characteristics of their contact structures in the mucosa of rat ileum. We examined target cells of neural connections and the characteristics of their contact structures by serial block-face scanning electron microscopy at four portions of the rat ileal mucosa: the apical and basal portions in the villi, and the lateral and basal portions around/in the crypts.

Morphological and phenotypical diversity of eosinophils in the rat ileum.

Eosinophils are abundantly present in intestinal mucosa. However, the morphological characteristics of their cellular population are still largely unknown. In this study, we examine their characteristics in the rat ileal mucosa using histological and ultrastructural methods.

Local surface plasmon resonance of gold nanoparticles as a correlative light and electron microscopy (CLEM) tag for biological samples.

In this study, we investigated use of local surface plasmon resonance (LSPR) of metal nanoparticles (NPs) as a correlative light and electron microscopy (CLEM) tag for biological samples. Gold NPs in ultra-thin sections for TEM revealed that LSPR could be observed by optical microscopy at sizes of 20 nm or larger. Gold NPs at sizes less than 20 nm could be observed using the gold enhancement method.

Three-dimensional analysis of fibroblast-like cells in the lamina propria of the rat ileum using serial block-face scanning electron microscopy.

Serial block-face scanning electron microscopy (SBF-SEM) is useful for three-dimensional observation of tissues or cells at high-resolution. In this study, SBF-SEM was used to three-dimensionally analyze the characteristics of fibroblast-like cells (FBLCs) in the rat ileal lamina propria (LP). The results revealed that FBLCs in LP could be divided into four types, tentatively named FBLC type I-IV, based on the external cellular appearance, abundance or shape of each organelle, detailed distribution in the LP and relationship with surrounding cells.

Development of novel correlative light and electron microscopy linkage system using silicon nitride film.

In this study, we investigated the optical properties of a silicon nitride (SiN) film. The thin SiN film (30 nm thick) exhibited good light transmittance and little autofluorescence and could be used as a microscope slide for optical microscopy (OM). In addition, we developed a novel correlative light and electron microscopy (CLEM) that combines OM with transmission electron microscopy (TEM) using an SiN thin film.

Fabrication and characterization of sample-supporting film made of silicon nitride for large-area observation in transmission electron microscopy.

In transmission electron microscopy (TEM), silicon nitride (SiN) films are widely used as sample-supporting films owing to their robustness. We fabricated large-scale SiN films deposited by low-pressure chemical vapor deposition (LPCVD). This preparation method is advantageous for large window areas, since it yields films with control over properties such as tension and thickness.

Imaging of Cell Shape Alteration and Cell Movement in Drosophila Gastrulation Using DE-cadherin Reporter Transgenic Flies.

Gastrulation is the first set of morphologically dynamic events that occur during the embryonic development of multicellular animals such as Drosophila. This morphological alteration is also recognized as epithelial to mesenchymal transition (EMT). Dysregulation of EMT is associated with fibrosis and cancer metastasis.

Characterization of paramyosin and thin filaments in the smooth muscle of acorn worm, a member of hemichordates.

Paramyosin is a myosin-binding protein characteristic of invertebrate animals, while troponin is a Ca-dependent regulator of muscle contraction. Both proteins are widely distributed in protostomes, while in deuterostomes, their distribution is limited; namely, presence of paramyosin and absence of troponin are common features in echinoderm muscles, while muscles of chordates contain troponin but lack paramyosin. In this study, we examined the muscle of a hemichordate, acorn worm, to clarify whether this animal is like echinoderms or like the other deuterostome animals.

The proximal half of the Drosophila E-cadherin extracellular region is dispensable for many cadherin-dependent events but required for ventral furrow formation.

The formation of the ventral furrow during Drosophila gastrulation is driven by coordinated apical constriction. Cell-cell adhesion is thought to regulate apical constriction, but the mechanisms are poorly understood. DE-cadherin, an epithelial classic cadherin, has in its membrane-proximal extracellular region a suite of domains absent from vertebrate/urochordate classic cadherins.