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This study aims to evaluate the changes in left ventricular diastolic function after coronary artery bypass grafting through tissue Doppler imaging (TDI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration and the correlation between the two.A total of 133 patients who underwent coronary artery bypass grafting between January 2016 and December 2018 were included in this study. Echocardiography and NT-proBNP concentration were reviewed pre-operation, 1 month post-operation, and 3-6 months post-operation. The transmitral peak flow velocity (E) of the mitral valve was measured at each of the three-time points using spectral Doppler imaging. The mitral annulus displacement (Ea peak and Aa peak) was then measured at each of the time points using TDI, and the E/Ea ratio was calculated. Subsequently, the correlation of the E value, Ea value, and E/Ea ratio with NT-proBNP concentration was statistically analyzed.The data obtained at the three-time points were compared with the respective concentrations of NT-proBNP. Multiple linear regression analysis revealed a correlation between NT-proBNP concentration and E value, Ea value, and E/Ea ratio.Left ventricular diastolic function gradually recovered at 1 month and 3-6 months after coronary artery bypass grafting. There was a correlation between TDI-related values and NT-proBNP concentration.

The radial velocity (RV) is a basic physical quantity which can be determined through Doppler shift of the spectrum of a star. The precision of RV measurement depends on the resolution of the spectrum we used and the accuracy of wavelength calibration. In this work, radial velocities of LAMOST-II medium resolution (R ~ 7500) spectra are measured for 1,594,956 spectra (each spectrum has two wavebands) through matching with templates. A set of RV standard stars are used to recalibrate the zero point of the measurement, and some reference sets with RVs derived from medium/high-resolution observations are used to evaluate the accuracy of the measurement. Comparing with reference sets, the accuracy of our measurement can get 0.0227 km s/1 with respect to radial velocities standard stars. The intrinsic precision is estimated with the multiple observations of single stars, which can achieve to 1.36 km s/1,1.08 km s/1, 0.91 km s/1 for the spectra at signal-to-noise levels of 10, 20, 50, respectively., published by ApJs. 13 pages, 13 figures

The formation behavior of coated explosive formed projectiles (CEFP) with different structure and material liners were numerically simulated by AUTODYN-2D. There are many factors affecting the coating effect of CEFP, the numerical simulation results show that the structure and liner material have remarkable influence on the velocity and forming effect of the CEFP. For the coating effect, the liner thickness has an optimum range. When the liner thickness is small or large, the explosive balls will deform seriously or not be wrapped sufficiently, and the EFP velocity decreases with increasing the axial thickness of the liner, when the liner thickness is 4.5mm and 5mm, the coating effect is the best. The curvature of liner also has an optimum interval, when the curvature of liner is small or large, the explosive balls will be lengthened or retrogradely compressed and destroyed, and the EFP velocity increases with the decreasing the curvature of the liner. When aluminum, iron, copper and tungsten are used as liner materials, the density and ductility of the material will affect the coating effect. The high density copper liner can achieve a good coating effect and well penetration performance.

The jet formation and penetration capability of hypervelocity double-layer liner shaped charges (HDLLSCs) against rolled homogeneous armor (RHA) targets are investigated by numerical simulation. The HDLLSCs with different cone angle and relative position of disc are simulated to investigate the influence of these parameters on penetration capability and compare with a traditional conical shaped charge (CSC). The simulation results show that, the tip velocity of the jet formed by HDLLSCs with a tantalum disc is lager by 6.8% compared with that formed by the CSCs. The three stages of jet formation for HDLLSC including converge, formation, and secondary impact are revealed and discussed. The penetration capability of HDLLSCs is influenced by the coupled effect of cone angle and relative position of disc, a larger relative position of disc is more suitable for a large cone angle. In addition, the standoff also has a significant effect on the penetration depth of HDLLSCs, the penetration depth increases from 3.31 charge diameter (CD) to 6.52 CD with the standoff increasing from 1.5 CD to 4.0 CD. Moreover, the penetration depth of the jet formed by HDLLSCs is larger by 18.5% compared with that formed by the CSCs at the standoff of 4.0 CD.

To explore the therapeutic potential of transplantation of adipose derived mesenchymal stem cells (ADMSCs) in rats osteoarthritis caused by anterior cruciate ligament transection.Rats peritoneal adipose tissues were used to extract ADMSCs.Cell morphological appearance was documented and flow cytometric cell cycle was used to identify ADMSCs. Anterior cruciate ligament transection was used to induce knee osteoarthritis in rats. ADMSCs were injected into the knee cavities. Knee joint pathology was performed to observe the treatment effects. QRT-PCR and Western blot were used to identify the targets of ADMSCs.ADMSCs were successfully extracted, separated, cultured and identified. Two and eight weeks after ADMSCs transplantation, pathology showed significantly attenuation of arthritis including osteophyte and synovitis, reflecting in significantly improvement of both osteophyte and synovitis grading compared to the controls. QRT-PCR and Western blot revealed that collagen Ⅱ expression was significantly up-regulated after ADMSCs transplantation compared to the controls.MMP-13, but not other MMP-1, MMP-3 or MMP-9 was reduced when ADMSCs were co-cultured with primary chondrocytes. DDR-2 expression in chondrocyte was heavily up-regulated when stimulated by TNF-α in vitro. However, ADMSCs could reverse the effect when co-cultured with chondrocyte, implying that ADMSCs may suppress the expression of DDR-2. IL-1β suppressed the cartilage differentiation of ADMSCs, and Actinomycin D (DDR-2 inhibitor) could reverse the effect.ADMSCs can attenuate osteoarthritis induced by anterior cruciate ligament transection in rats by suppressing the expression of MMP-13, and the upstream target spot may be DDR-2.

An HPLC method was developed with normal HPLC-chiral complex mobile phase for the separation and determination of D- and L-thyroxine enantiomers (D- and L-T4) in human plasma. The method includes extraction of thyroxine from plasma and separation of thyroxine enantiomers on HPLC silica column with chiral eluent containing L-proline, cupric acetate and triethylamine (TEA). The sensitivity of the method was 0.1 mg/L. The precisions of inter-day and intra-day, linearity, extraction recovery, and stability of T4 enantiomers in plasma and in deproteinized plasma were determined for the validation of the method. Baseline enantioseparation of the compounds containing D- and L-T4 was achieved. Meantime we determined the concentrations of D-T4 and L-T4 in plasma of 15 volunteers with euthyroid, hypothyroid and hyperthyroid symptoms. Liquid chromatographic method based on the described procedure was useful for the determination of D- and L-thyroxine in patient plasma and for pharmacokinetics investigation.

Postnatal mammary gland development is highly dependent on the ovarian steroids, estrogen and progesterone. However, evidence from both in vitro and in vivo studies indicates that steroid-induced development occurs indirectly, requiring stromal cooperation in epithelial proliferation and morphogenesis. Stromal cells appear to influence epithelial cell behavior by secretion of growth factors and/or by altering the composition of the extracellular matrix in which epithelial cells reside. This review will discuss the requirement for stromal tissue in modulating proliferative responses to ovarian hormones during postnatal development and the potential role of the EGF, IGF, HGF and FGF3 growth factor families. Additionally, the roles of extracellular matrix proteins, including fibronectin, collagens and laminin, will be summarized.