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Background: The aim of the study was to probe the morphological features of the proximal segment (V1) of vertebral artery (VA) in a sample of Chinese cadavers.Materials and Methods: The origin, course and outer diameter at origin of the pre-vertebral part of the VAs were evaluated in 119 adult cadavers.Results: It was found that 94.12% of the VAs originated from the subclavian arteries, bilaterally. The variant origins were present in 5.88% of the cadavers and all originated directly from the arch of the aorta. All the variations were observed on the left side of male cadavers. The average outer diameters at origin of the normal and variation groups were 4.35 ± 1.00 mm and 4.82 ± ± 1.42 mm, respectively, p = 0.035. In the normal group, but not in the variation group, the average diameter in the males was significantly larger than that in the females (4.50 ± 0.99 mm, 3.92 ± 0.92 mm, respectively, p = 0.000). In addition, only 5 cadavers in the normal group had hypoplastic VAs (4.20%, 4 males, 3 right-sided). Vertebral artery dominance (VAD) was present in 91 (69 males) out of 112 cadavers and more common on the left (n = 48). In addition, 3 cadavers satisfied conditions for coexistence of VAD and vertebral artery hypoplasia. All 7 cadavers in the variation group exhibited VAD, which was more common on the right side (n = 5).Conclusions: The morphologic variations and frequencies described above have implications for the early prevention, abnormal anatomy detection, accurate diagnosis, safe surgery and endovascular treatment of cardiovascular and neurological disease. [ABSTRACT FROM AUTHOR]

The complete magnetic and multiferroic phase diagram of Mn1-xCoxWO4 single crystals is investigated by means of magnetic, heat capacity and polarization experiments. We show that the ferroelectric (FE) polarization E P in the multiferroic state abruptly changes its direction twice upon increasing Co content, x. At xc1 = 0.075, E P rotates from the b-axis into the a-c-plane and at xc2 = 0.15 it flips back to the b-axis. The origin of the multiple polarization flops is identified as an effect of the Co anisotropy on the orientation and shape of the spin helix leading to thermodynamic instabilities caused by the decrease of the magnitude of the polarization in the corresponding phases. A qualitative description of the FE polarization is derived by taking into account the intrachain (c-axis) as well as the interchain (a-axis) exchange pathways connecting the magnetic ions. In a narrow Co concentration range (0.1 ⩽ x ⩽ 0.15), an intermediate phase, sandwiched between the collinear hightemperature and the helical low-temperature phases, is discovered. The new phase exhibits a collinear and commensurate spin modulation similar to the low-temperature magnetic structure of MnWO4. [ABSTRACT FROM AUTHOR]

Background: Recently, transcriptional gene silencing induced by small interfering RNA (siRNA) was found in mammalian and human cells. However, previous studies focused on endogenous genes.Methods: In this study, we designed siRNA targeting the promoter of human papillomavirus 16 E6/E7 and transfected it into the cervical cancer cell line, SiHa. E6 and E7 mRNA and protein expression were detected in cells treated by promoter-targeting siRNA. Futhermore, cellular growth, proliferation, apoptosis and senescence were detected. Thereafter, we investigated promoter DNA methylation and histone methylation status in cells treated with promoter-targeting siRNA.Results: We found that E6/E7 mRNA and protein were simultaneously reduced, cell growth and proliferation were inhibited and cell death, especially senescence, was remarkably increased. Meanwhile, we also found a significantly increasing histone H3-Lys9 methylation on the promoter when E6/E7 gene expression was inhibited.Interpretation: Our findings suggest that promoter-targeting siRNA effectively and simultaneously knocks down both extraneous HPV 16 E6 and E7 at the transcriptional level, and consequently inhibits proliferation and induces death in HPV 16-infected cells. This transcriptional repression is probably induced by histone modification rather than by alteration of DNA methylation. [ABSTRACT FROM AUTHOR]

Abstract A novel solgel process has been successfully developed for preparing strontium bismuth tantalate (SrBi2Ta2O9, known as SBT) with ethylene alcohol as a solvent and acetic acid as a catalyst. The size of phase-pure SBT nanoparticles could be 4 nm in diameter by avoiding the formation of the fluorite phase at the low temperatures (550600C). The behavior of the crystallization in SBT is investigated by XRD, TG-DTA, FT-IR and TEM. The nanoparticle size as a function of the annealing temperature is also investigated. By fitting the Arrhenius curve, we obtain the crystalline and vitreous growth activation energies, i.e, Ea1 = 0.709 eV and Ea2 = 0.093 eV. The two other fitting parameters, transition temperature T0 = 814 K (541C) and transition width ? = 0.022, directly show the behavior of the phase transition from vitreous phase to crystalline phase. [ABSTRACT FROM AUTHOR]