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Fukuyama congenital muscular dystrophy (FCMD) is a severe, intractable genetic disease that affects the skeletal muscle, eyes, and brain and is attributed to a defect in alpha dystroglycan (αDG) O-mannosyl glycosylation. We previously established disease models of FCMD; however, they did not fully recapitulate the phenotypes observed in human patients. In this study, we generated induced pluripotent stem cells (iPSCs) from a human FCMD patient and differentiated these cells into three-dimensional brain organoids and skeletal muscle. The brain organoids successfully mimicked patient phenotypes not reliably reproduced by existing models, including decreased αDG glycosylation and abnormal radial glial (RG) fiber migration. The basic polycyclic compound Mannan-007 (Mn007) restored αDG glycosylation in the brain and muscle models tested and partially rescued the abnormal RG fiber migration observed in cortical organoids. Therefore, our study underscores the importance of αDG O-mannosyl glycans for normal RG fiber architecture and proper neuronal migration in corticogenesis.

This study investigates the surface functionalization of plastic substrates through dip‐coating in azide‐functionalized polymer solutions, followed by a click reaction (i.e., strain‐promoted azide–alkyne cycloaddition). Acrylic, poly(ethylene terephthalate) (PET), and nylon substrates are dip‐coated with a series of polymers containing various azide groups grafted onto the poly(methyl methacrylate‐co‐hydroxyethyl methacrylate) backbone to examine structural effects on the surface density of clickable azide groups. X‐ray photoelectron spectroscopy and fluorescence spectroscopy confirm the subsequent click‐immobilization of cycloalkyne‐tagged fluorescein, which is quantified to calculate the surface density of clickable azide groups. Further investigations demonstrate that the surface density of azide groups can be controlled by manipulating the polymer ratio during dip‐coating, thus enabling the preparation of a linear surface gradient in terms of azide group density. Finally, the microcontact printing (µCP) method is employed to pattern the functionalized surfaces and quantify the functional molecules immobilized on the surface by µCP. This study highlights the adaptability of click chemistry and polymer coating techniques for the advanced functionalization of plastic surfaces for materials science and engineering applications. [ABSTRACT FROM AUTHOR]

The photothermal heating properties of perfectly spherical crystalline silicon nanoparticles having Mie resonances in the visible range are studied under different illumination wavelengths by using the Raman scattering peak as a nanothermometer. Analytical calculations reveal that the magnetic quadrupole (MQ) Mie mode is the most suitable mode for photothermal heating. The experimentally obtained size and illumination wavelength dependence of the temperature rise agrees quantitatively with numerical simulations, and the heating efficiency reaches up to 381 K/(mW/μm2) when the illumination wavelength of 633 nm matches the MQ resonance. Conversely, tuning the illumination wavelength to a relatively nonabsorbing mode, such as the electric dipole (ED) mode, can significantly reduce the heating effect. In this context, the ED mode functions as a practically heating-less nanoantenna, promoting the surface-enhanced fluorescence of nearby dye molecules, while high-Q modes, e.g., MQ and electric quadrupole (EQ) modes, serve as an optical heating platform. Furthermore, the photothermal heating and Raman thermometry of silicon nanoparticles in water and in cancer cells are demonstrated. [ABSTRACT FROM AUTHOR]

The discovery of novel antibacterial drugs against infectious diseases has decreased over the past few decades because of their poor cost performance. In this study, we report that the nanoassembly of a short-peptide hydrogelator (P1) endowed novel antifungal selectivity to a conventional antifungal drug, amphotericin B (AmB), which expands its application spectrum. Clinical use of AmB is limited because of poor water solubility and poor selectivity in its toxicity, which often causes harmful effects on tissues. P1 was the low-molecular-weight hydrogelator (LMWHg) that showed low cytotoxicity and was enzymatically degraded. In general, an LMWHg entraps foreign hydrophobic molecules inside the hydrophobic space in the self-assembled body. P1 successfully solubilized AmB in water as a form of a nanocomplex (NC) that had a chain-like structure. The NCs showed remarkably low toxicity toward Saccharomyces cerevisiae as a model fungus when compared with free AmB, meaning that P1 suppressed the antifungal activity of AmB via coassembly. The suppressed antifungal activity of AmB recovered when P1 in the NCs was degraded by a protease to liberate AmB from the coassembly with P1. P1 at a high concentration formed a hydrogel incorporating AmB (AmB-P1 gel), in which the antifungal activity of AmB was suppressed as well as that in the NC. The coassembly with AmB affected the morphology of the P1 self-assembly. While S. cerevisiae that did not secrete proteases formed a colony on the AmB-P1 gel, Aspergillus oryzae that secreted proteases did not grow on the AmB-P1 gel at all, resulting in the selective killing of the fungus. Because some of malignant, infectious fungi secrete proteases, the coassembly strategy of conventional antifungal drugs with self-assembling molecules should lead to "drug repositioning" of approved drugs in the health and medical fields. [ABSTRACT FROM AUTHOR]