Giant Enhancement of Hole Mobility for 4H-Silicon Carbide through Suppressing Interband Electron-Phonon Scattering.

4H-silicon carbide (4H-SiC) possesses a high Baliga figure of merit, making it a promising material for power electronics. However, its applications are limited by low hole mobility. Herein, we found that the hole mobility of 4H-SiC is mainly limited by the strong interband electron-phonon scattering using mode-level first-principles calculations. Our research indicates that applying compressive strain can reverse the sign of crystal-field splitting and change the ordering of electron bands close to the valence band maximum. Therefore, the interband electron-phonon scattering is severely suppressed and the electron group velocity is significantly increased. The out-of-plane hole mobility of 4H-SiC can be greatly enhanced by ∼200% with 2% uniaxial compressive strain applied. This work provides new insights into the electron transport mechanisms in semiconductors and suggests a strategy to improve hole mobility that could be applied to other semiconductors with hexagonal crystalline geometries.

Silencing of PFKFB3 protects podocytes against high glucose­induced injury by inducing autophagy.

Diabetic nephropathy (DN) is a diabetic complication that threatens the health of patients with diabetes. In addition, podocyte injury can lead to the occurrence of DN. The protein 6­phosphofructo­2­kinase/fructose­2,6-biphosphatase 3 (PFKFB3) may be associated with diabetes; however, the effects of PFKFB3 knockdown by small interfering (si)RNA on the growth of podocytes remains unknown. To investigate the mechanism by which PFKFB3 mediates podocyte injury, MPC5 mouse podocyte cells were treated with high­glucose (HG), and cell viability and apoptosis were examined by Cell Counting Kit­8 assay and flow cytometry, respectively. In addition, the expression of autophagy­related proteins were measured using western blot analysis and immunofluorescence staining. Cell migration was investigated using a Transwell assay and phalloidin staining was performed to observe the cytoskeleton. The results revealed that silencing of PFKFB3 significantly promoted MPC5 cell viability and inhibited apoptosis. In addition, the migration of the MPC5 cells was notably downregulated by siPFKFB3. Moreover, PFKFB3 silencing notably reversed the HG­induced decrease in oxygen consumption rate, and the HG­induced increase in extracellular acidification rate was rescued by PFKFB3 siRNA. Furthermore, silencing of PFKFB3 induced autophagy in HG­treated podocytes through inactivating phosphorylated (p­)mTOR, p­AMPKα, LC3 and sirtuin 1, and activating p62. In conclusion, silencing of PFKFB3 may protect podocytes from HG­induced injury by inducing autophagy. Therefore, PFKFB3 may serve as a potential target for treatment of DN.

[Clinical immunological study on prevention and treatment of chronic pyelonephritis with yishenkang granule].

OBJECTIVE: To investigate the relationship between chronic pyelonephritis (CPN) and immune function, and the therapeutic mechanism of Yishenkang granule (YSKG). METHODS: One hundred and twenty patients of CPN were divided into 3 groups randomly, the YSKG group (treated with YSKG), the control A group (treated with Sanjin tablet) and the control B group (treated with western medicine). Serum levels of immunoglobulin (Ig), complement 3 (C3), interleukin-2 (IL-2), peripheral T-lymphocyte subsets, and urinary secretory immunoglobulin A (sIgA) were determined before and after treatment with monoclonal antibody assay, agar diffusion method, radioimmunoassay (RIA), and radioimmuno-equilibrium method, and compared with normal control. RESULTS: There were disorders of T-lymphocyte subsets in CPN, lowering of serum Ig, C3 and urinary sIgA, and increase of blood IL-2 (P < 0.05 or P < 0.01). These abnormalities could be normalized after YSKG treatment. CONCLUSION: Functional disorders of cellular and humoral immunity exist in CPN patients of chronic stage, YSKG could correct the immune functional disorder, control the recurrence of CPN effectively and alleviate the immunopathological damage.