Angiogenesis is controlled positively or negatively by extrinsic and intrinsic molecular cues in endothelial cells (ECs); in the tumor microenvironment, the action of positive regulators exceeds that ...of negative regulators. Thus, overinduction of negative regulators may inhibit tumor angiogenesis. MicroRNAs (miRNAs or miRs) are endogenous short noncoding RNAs regulating gene expression either through translational inhibition or destabilization of target mRNA. Here, we show that miR-125b expression is transiently induced in ECs on stimulation with vascular endothelial growth factor or by ischemia. miR-125b inhibits translation of vascular endothelial (VE)-cadherin mRNA and in vitro tube formation by ECs. Injection of miR-125b into the tumor inhibited VE-cadherin expression by ECs and induced nonfunctional blood vessel formation, resulting in inhibition of tumor growth. It has been suggested that pro-angiogenic signals in ECs also upregulate anti-angiogenic molecules simultaneously via negative feedback. Because miR-125b induction in ECs is transient after pro-angiogenic stimulation, prolonged overexpression of miR-125b could result in blood vessel regression. Thus, miR-125b may be useful in cancer therapy by causing the collapse of the lumen of ECs.
Arterial stiffness is reported to be able to cause axonal demyelination or degeneration. The present study aimed to use advanced MR imaging techniques to examine the effect of arterial stiffness on ...the WM microstructure among older adults.
Arterial stiffness was measured using the cardio-ankle vascular elasticity index (CAVI). The high-CAVI (mean CAVI ≥ 9 points) and the low-CAVI groups (mean CAVI < 9 points) were created. The neuronal fiber integrity of the WM was evaluated by neurite orientation dispersion and density imaging and magnetization transfer saturation imaging. Tract-Based Spatial Statistics and the tracts-of-interest analysis were performed. Specific WM regions (corpus callosum, internal capsule, anterior thalamic radiation, corona radiata, superior longitudinal fasciculus, forceps minor, and inferior fronto-occipital fasciculus) were selected in the tracts-of-interest analysis.
In Tract-Based Spatial Statistics, the high-CAVI group showed a significantly lower myelin volume fraction value in the broad WM and significantly higher radial diffusivity and isotropic volume fraction values in the corpus callosum, forceps minor, inferior fronto-occipital fasciculus, internal capsule, corona radiata, and anterior thalamic radiation than the low-CAVI group. In tracts-of-interest analysis using multivariate linear regression, significant associations were found between the mean CAVI and radial diffusivity in the anterior thalamic radiation and the corona radiata; isotropic volume fraction in the anterior thalamic radiation and the corona radiata; and myelin volume fraction in the superior longitudinal fasciculus (
< .05). Additionally, partial correlation coefficients were observed for the significant associations of executive function with radial diffusivity and myelin volume fraction (
< .05).
Arterial stiffness could be associated with demyelination rather than axonal degeneration.
Context. CH Cyg is one of the most studied symbiotic stars. Its properties, however, are still not well known. Two main periods, about 15 years and 750 days, are known in the photometric and ...spectroscopic variations, and two models are proposed for these origins. One is a binary system with an orbital period of 15 years consisting of a hot component and pulsating red giant with a 750-day period. The other is a triple system consisting of an inner symbiotic binary with an orbital period of about 750 days and third component with an orbital period of 15 years. Several active stages have been observed since the 1970s during which the object brightened up by ΔU = 3−5 mag and prominent emission lines appeared. Large mass outflows were observed at some active stages. Aims. The spectral variation of CH Cyg has been monitored at Asiago Observatories to understand the problems mentioned above. We have analysed spectra obtained in the time period from 1995 to 2004 which covers an active stage during the years 1998−2000. Methods. High- and low-resolution optical spectra obtained at the Asiago Observatories are used. Results. Narrow absorption lines of Fe I, Cr I, Ti I, and so on appeared in 1998 at an early phase of the active stage. These lines are clearly distinguished from those of the M-type giant and are typically found on the spectrum of early A-type dwarfs. They were redshifted by about 30 km s−1 with respect to the absorption lines of the M-type giant. Assuming that their radial velocities represent the orbital motion of the hot component, its semi-amplitude is estimated to be 37.0 ± 0.5 km s−1. The masses of the hot component and the M-type giant are estimated to be 0.32 ± 0.02 M⊙ and 4.6 ± 0.2 M⊙, respectively, where a circular orbit with a period of 756 days is adopted. If the inner binary system has an elliptical orbit, e = 0.33, and a period of 750.1 days, the masses of the two components are 0.21 ± 0.01 M⊙ and 2.2 ± 0.1 M⊙, respectively. Our results lend support to the triple system model, because if the period of the symbiotic binary were 15 years, the mass of the hot component would be expected to exceed the Chandrasekhar limit. Highly blueshifted absorption components of H I and He I lines appeared at a later phase of the active stage. Mass ejections with velocities on the order of 1000 km s−1 seem to have occurred along the orbital plane from December 1998 to March 1999. The highest outflow velocity, − 2383 km s−1, was observed on 1999 February 26. Narrow absorption components of Na I D1, D2, and Fe II lines redshifted by 10−15 km s−1 coexisted with the highly blueshifted broad absorption components of H I and He I lines. This phenomenon might have been related to an inner disc inflow expected in wind-compressed discs. In contrast to the bipolar mass outflows at the past active stages, high-velocity equatorial mass ejections likely occurred at the active stage during the years 1998−2000. There should have been an eclipse of the hot component by the M-type giant in the inner binary system in the time period of December 1998 to January 1999. A clear light curve of the eclipse, however, was not detected. Possibly, the luminosity of the hot component was due mainly to free-free emission from the ejected circumstellar matter which was likely more extended than the M-type giant. On the other hand, another eclipse by the third component with the period of 15 years began at the end of May 1999 during which the hot component as well as the emitting regions of Hβ and Fe II lines were well eclipsed. The obscuring matter around the third component should have been much more extended than the M-type giant, and it was likely semi-transparent, because the spectrum of the M-type giant was well seen during the eclipse. The third component appears to be similar to the invisible secondary component in the long-period eclipsing binary ϵ Aur.
Context. The outburst of the symbiotic recurrent nova V407 Cyg in 2010 has been studied by numerous authors. On the other hand, its spectral variations in the quiescent stage have not been well ...studied yet. This paper is probably the first report for the relation between the pulsation of the secondary Mira variable and the temperature of the primary hot component for V407 Cyg. Aims. The spectral variation in the post-outburst stage has been monitored to study the properties of this object. In the course of this work, we found some unexpected spectral variations around the light maximum of the secondary Mira variable in 2012. The relation between the mass transfer in the binary system and the pulsation of the secondary Mira variable is studied. Methods. High- and low-resolution optical spectra obtained at the Astronomical Observatories at Asiago were used. The photometric data depend on the database of the VSNET. Results. The secondary Mira variable reached its light maximum in 2012, when an absorption spectrum of a late-M-type giant developed and the emission line of Hδ became stronger than those of Hβ and Hγ, which are typical spectral features of Mira variables at light maxima. On the other hand, intensity ratios to Hβ of the emission lines of He I, He II, Fe VII, etc., which obviously depended on the temperature of the hot component, rapidly varied around the light maximum. The intensity ratios started to decrease at phase about 0.9 of the periodical light variation of the Mira variable. This phenomenon suggests that the mass transfer rate, as well as the mass accretion rate onto the hot component, decreased according to the contraction of the Mira variable. However, these intensity ratios somewhat recovered just on the light maximum: phase 0.99. There might have occurred a temporal mass loss from the Mira variable at that time. The intensity ratios decreased again after the light maximum, then recovered and returned to the normal level at phase about 0.1. Since the mass transfer rate seems to have been closely related to the pulsation of the secondary component, the mass transfer in this binary system was likely due to a normal Roche-lobe overflow. If this is the case, the orbital period should be shorter than five years. Each of the Na I D1 and D2 lines had five emission and one absorption components around the light maximum. It seems that there were two pairs of mass outflows from the Mira variable with velocities of ± 79 km s-1 and ± 44 km s-1. These velocities were much higher than those of mass loss from usual Mira variables.
Immature and unstable tumor vasculature provides an aberrant tumor microenvironment and leads to resistance of tumors to conventional therapy. Hence, normalization of tumor vessels has been reported ...to improve the effect of immuno-, chemo- and radiation therapy. However, the humoral factors, which can effectively induce maturation of tumor vasculature, have not been elucidated. In this study, we found that the novel peptide apelin and its receptor APJ can induce the morphological and functional maturation of blood vessels in tumors. This apelin-induced tumor vascular maturation enhances the efficacy of cancer dendritic cell-based immunotherapy and significantly suppresses tumor growth by promoting the infiltration of invariant natural killer T cells into the central region of the tumor and thereby robustly inducing apoptosis of tumor cells. Additionally, we showed APJ expression to be enhanced in the tumor endothelium in comparison with normal-state endothelial cells. These findings provide a new target for tumor vascular-specific maturation, which is expected to improve the efficacy of conventional cancer therapies.
This study clarified the association between acceleration and the rates of changes in spatiotemporal variables on a step-to-step basis during the entire acceleration phase of maximal sprinting. 21 ...male sprinters performed a 60-m sprint, during which step-to-step acceleration and rates of changes in step length (RSL) and step frequency (RSF) were calculated. The coefficients of correlation between acceleration and other variables were tested at each step. There were positive correlations between acceleration and the RSF up to the second step. Acceleration was positively correlated with the RSL from the 5(th) to the 19(th) step. At the third and from the 16(th) to the 22(nd) step and from the 20(th) to the 21(st) step, there was no significant correlation, but weak relationships were found between acceleration and the RSF and RSL. The results suggest that the acceleration phase can be divided into 3 sections, and for sprinting to be effective, it is important to accelerate by increasing the step frequency to the third step, increasing the step length from the 5(th) to the 15(th) step, and increasing the step length or frequency (no systematic relative importance of step length or frequency) from the 16(th) step in the entire acceleration phase.
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