Search

Background and objective Oxidative stress has been suggested as an important pathogenic factor contributing to chronic periodontitis with diabetes mellitus (CPDM). Previous studies have revealed the potential therapeutic properties of baicalein (BCI) in oxidative stress-related diseases; however, the antioxidant effects of BCI on therapy for individual with CPDM remain largely unexplored. Nuclear factor erythroid 2-related factor 2 (Nrf2) plays a critical role in cellular defence against oxidative stress. In this study, we aim to determine whether BCI prevents diabetes-related periodontal tissue destruction by regulating Nrf2 signaling pathway. Material and methods Human gingival epithelial cells (hGECs) were challenged with high glucose (HG, 25 mmol/L) and/or lipopolysaccharide (LPS, 20 µg/mL). Reactive oxygen species (ROS) were detected by fluorescence-activated cell sorting. The changes of antioxidant-related genes, including Nrf2, catalase (Cat), glutamate-cysteine ligase catalytic subunit (Gclc), superoxide dismutase 1 (Sod1), and superoxide dismutase 2 (Sod2), were quantified by real-time PCR. The localization of phospho-Nrf2 (pNrf2, S40) in the nucleus was detected by immunofluorescence staining and laser scanning confocal microscope (LSCM). PNrf2 and total form of Nrf2 were determined using western blot. The above indicators together with mitochondrial membrane potential (MMP) were further investigated in hGECs pre-treated with different concentrations of BCI (0.01, 0.1, or 0.5 µg/mL) before stimulated with HG plus LPS (GP). Finally, the role of BCI in activating Nrf2 signaling pathway and relieving the alveolar bone absorption was examined in the CPDM model of Sprague Dawley rats. CPDM rats were oral gavaged with BCI (50, 100, or 200 mg/kg daily). The pNrf2 was detected by immunohistochemistry, and the alveolar bone absorption was examined by microcomputed tomography. Results Our results showed that ROS were significantly increased in both groups of HG and LPS, with the strongest generation in the GP group. In terms of ROS-related gene expression, we found that the mRNA levels of Nrf2, Cat, Gclc, Sod1, and Sod2 were significantly decreased in HG and LPS groups. In consistent with the strongest induction of ROS in GP group, the gene expression in GP group was further decreased as compared to those of HG and LPS groups. Also, the expression of pNrf2 exhibited the same trend with the expression of those antioxidant genes. However, the generation of ROS and the loss of mitochondrial membrane potential induced by GP were abolished by pre-treatment with different concentrations of BCI (0.01, 0.1, or 0.5 µg/mL). Interestingly, we observed that BCI promoted the nucleus translocation of pNrf2, as well as the gene expression levels of pNrf2 and its target genes (Cat, Gclc, Sod1, and Sod2). Finally, in the CPDM animal model, we found that BCI (at concentrations: 50, 100, and 200 mg/kg) markedly increased the number of pNrf2-positive cells in periodontal tissue and mitigated the alveolar bone loss. Conclusions Our data revealed a potential role for clinic application of BCI under CPDM conditions, suggesting a new therapeutic drug for CPDM patients.

Objectives Diabetes aggravates the risk and severity of periodontitis, but the specific mechanism remains confused. Complement 3 (C3) is closely related to complications of type 2 diabetes (T2DM). In the present study, we concentrated on whether C3 mediates the development of periodontitis in T2DM. Materials and Methods Levels of C3 in blood and gingival crevicular fluid (GCF) of patients were measured first. A C3‐knockout diabetic mouse model was established, real‐time PCR, Western blotting and histological investigation were performed to evaluate the progress of periodontitis. Microcomputed tomography (micro‐CT) and TRAP staining were performed to detect alveolar bone resorption. Immunofluorescence was performed to detect polarization of macrophages. Results Our data showed that C3 levels were elevated in the blood and GCF of T2DM patients compared with non‐diabetic individuals. Increased C3 was closely related to the upregulation of inflammatory cytokines including interleukin (IL)‐1, IL‐6 and tumour necrosis factor‐alpha (TNF‐α), as well as the decline of the bone volume density (BMD) and bone volume over total volume (BV/TV) of the alveolar bones in diabetic mice. The deletion of C3 inhibited inflammatory cytokines and rescued the decreased BMD and BV/TV of the alveolar bones. C3‐mediated polarization of macrophages was responsible for the damage. Conclusion T2DM‐related upregulation of C3 contributes to the development of periodontitis by promoting macrophages M1 polarization and inhibiting M2 polarization, triggering a pro‐inflammatory effect on periodontal tissues., T2DM led to an increase in C3 levels, which affected the macrophages in periodontal tissues by promoting macrophages to polarize to M1 and inhibiting M2 polarization, thus triggering a pro‐inflammatory effect on periodontal tissues. C3‐related osteoclasts increase potentially promoted alveolar bone resorption.

An efficient and exact spectral integral method (SIM) for the general problems of scattering by a circular cylinder is presented, both for acoustic and electromagnetic cases. Fast Fourier transform (FFT) and convolution theorem help us to execute the algorithm efficiently with O(Nlog(N)) computational complexity. The Fourier coefficients of the integral kernels are computed in a semianalytical way to accomplish a fast convergence rate with spectral accuracy. Compared with the method not using the semianalytical forms, without the increase of the computing and memory abundance, it saves more than 90% sampling points to achieve about the same accuracy, and with the same number of sampling points, several to more than ten orders of magnitude more accuracy can be achieved. For example, for the tested large wavenumber case with 2 × 106 wavelengths on the boundary, only two sampling points per wavelength are required to achieve a relative error of less than 0.001%. More than 90% computational time is saved compared with the normal summation formula of harmonic cylinder expansions. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Understanding the underlying physics of interactions among various quasi-particles is a fundamental issue for the application of spintronics and photonics. Here the observation of a coupling between the small polarons in the nanoscale ultrathin La0.7Sr0.3MnO3 (LSMO) films and the acoustic phonons in the SrTiO3 (STO) substrate using ultrafast pump–probe spectroscopy has been reported. According to the temperature- and wavelength-dependent measurements, the amplitudes of the acoustic phonons are suppressed by tuning the small polarons absorption. This shows a coupled relationship between the acoustic phonons and the small polarons. At the probe photon energy of 1.55 eV where the polaron absorption is dominant, the acoustic phonons become unobservable. Furthermore, by performing the pump fluence dependent measurements on the LSMO films with different thicknesses, smaller acoustic phonon amplitudes are found in the thinner film with stronger small polaron binding energy. Such a coupled nature can be utilized to manipulate the small polarons using the acoustic phonons or vice versa, which is of great importance in device applications of colossal magnetoresistance materials.

A new method for the synthesis of wideband frequency-invariant pencil-beam patterns with nonuniformly spaced linear arrays is proposed. This scheme is designed under the framework of fast multitask compressive sensing. The minimum spacing between antenna elements can be controlled to make sure that the obtained arrays are physically realizable. The results achieved are comparable to those obtained by the state-of-the-art techniques. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.