Goal: For personalized clinical applications, flexible conductors require both high electrical conductivity and resistance to stretching and bending. Here, we developed a two-dimensional array ...sinusoidal wave (TDAS) conductor, characterized its electrical properties under stretching and bending loads, and measured photoelectric pulse waves. Methods: TDAS structures with wavelengths of 500−2000 μm and amplitudes of 50−200 μm were microfabricated on Al substrates. These structures were then transferred to dimethylpolysiloxane, followed by Au sputtering to obtain TDAS conductors. Results: TDAS conductors with a 200-μm amplitude suppressed the increase in resistance to stretching and bending and maintained conductivity >30% stretching. The small cracks in the valleys observed with electron microscopy contributed to its stretching properties. The connection of LEDs and photodiodes to the TDAS conductors enabled fingertip pulse wave detection. Conclusions: Film-type TDAS conductors, which can maintain high conductivity during stretching and bending, have potential for stress-free physiological monitoring of organs such as the heart as well as the body surface.
Vital pulp therapy (VPT) is to preserve the nerve and maintain healthy dental pulp tissue. Laser irradiation (LI) is beneficial for VPT. Understanding how LI affects dental pulp cells and tissues is ...necessary to elucidate the mechanism of reparative dentin and dentin regeneration. Here, we show how Er:YAG-LI and diode-LI modulated cell proliferation, apoptosis, gene expression, protease activation, and mineralization induction in dental pulp cells and tissues using cell culture, immunohistochemical, genetic, and protein analysis techniques. Both LIs promoted proliferation in porcine dental pulp-derived cell lines (PPU-7), although the cell growth rate between the LIs was different. In addition to proliferation, both LIs also caused apoptosis; however, the apoptotic index for Er:YAG-LI was higher than that for diode-LI. The mRNA level of odontoblastic gene markers-two dentin sialophosphoprotein splicing variants and matrix metalloprotease (MMP)20 were enhanced by diode-LI, whereas MMP2 was increased by Er:YAG-LI. Both LIs enhanced alkaline phosphatase activity, suggesting that they may help induce PPU-7 differentiation into odontoblast-like cells. In terms of mineralization induction, the LIs were not significantly different, although their cell reactivity was likely different. Both LIs activated four MMPs in porcine dental pulp tissues. We helped elucidate how reparative dentin is formed during laser treatments.
Transforming growth factor-beta (TGF-β) is critical for cell proliferation and differentiation in dental pulp. Here, we show the dynamic mechanisms of TGF-β in porcine dental pulp, odontoblasts and ...dentin. The mRNA of latent TGF-β1 and TGF-β3 is predominantly expressed in odontoblasts, whereas the mRNA expression level of latent TGF-β2 is high in dental pulp. TGF-β1 is a major isoform of TGF-β, and latent TGF-β1, synthesized in dental pulp, is primarily activated by matrix metalloproteinase 11 (MMP11). Activated TGF-β1 enhances the mRNA expression levels of MMP20 and full-length dentin sialophosphoprotein (DSPP) in dental pulp cells, coinciding with the induction of odontoblast differentiation. Latent TGF-β1 synthesized in odontoblasts is primarily activated by MMP2 and MMP20 in both odontoblasts and dentin. The activity level of TGF-β1 was reduced in the dentin of MMP20 null mice, although the amount of latent TGF-β1 expression did not change between wild-type and MMP20 null mice. TGF-β1 activity was reduced with the degradation of DSPP-derived proteins that occurs with ageing. We propose that to exert its multiple biological functions, TGF-β1 is involved in a complicated dynamic interaction with matrix metalloproteinases (MMPs) and/or DSPP-derived proteins present in dental pulp, odontoblasts and dentin.
To investigate potential functions of transforming growth factor-beta (TGF-β) isoforms in maturation-stage ameloblasts during amelogenesis.
In vivo activation of TGF-β was characterized by using ...matrix metalloproteinase 20 null (Mmp20-/-) and wild-type (Mmp20+/+) mice. Using mHAT9d cells cultured in the presence of each TGF-β isoform, (1) cell proliferation was determined by MTS assay, (2) immunostaining with anti-cleaved caspase-3 monoclonal antibody was performed and apoptotic indices were measured, (3) gene expression was analyzed by RT-qPCR, and (4) the uptake of amelogenin into mHAT9d cells was directly observed using a fluorescence microscope.
TGF-β1 and TGF-β3 were present in the enamel matrix of developing teeth which were activated by MMP20 in vivo. A genetic study revealed that the three TGF-β isoforms upregulate kallikrein 4 (KLK4) mRNA levels but downregulate carbonic anhydrase II. Moreover, TGF-β1 and TGF-β2 significantly upregulated the mRNA level of amelotin, whereas TGF-β3 dramatically downregulated the mRNA levels of odontogenic ameloblast-associated protein (ODAM), family with sequence similarity 83 member H (FAM83H), and alkaline phosphatase (ALP). Immunostaining analysis showed that the apoptosis of mHAT9d cells is induced by three TGF-β isoforms, with TGF-β3 being most effective. Both TGF-β1 and TGF-β3 induced endocytosis of amelogenin.
We propose that TGF-β is regulated in an isoform-specific manner to perform multiple biological functions such as gene expression related to the structure of basal lamina/ameloblasts, mineral ion transport, apoptosis, and endocytosis in maturation-stage ameloblasts.
Display omitted
•Of three TGF-β isoforms (TGF-β1, TGF-β2 and TGF-β3), TGF-β1 and TGF-β3 are present in the enamel matrix of developing teeth which were activated by MMP20 in vivo.•Three TGF-β isoforms upregulate and downregulate mRNA levels in maturation-stage ameloblasts in an isoform-specific manner.•Although three TGF-β isoforms induce the apoptosis of maturation-stage ameloblasts, TGF-β3 is most effective.•Both TGF-β1 and TGF-β3 induce endocytosis of amelogenin.
PDF
