LINC00665 facilitates the progression of osteosarcoma via sponging miR-3619-5p.

OBJECTIVE: Long non-coding RNAs (lncRNAs) play vital roles in the pathogenesis and development of multiple cancers, including osteosarcoma (OS). The present study aims to investigate the role of LINC00665 in OS progression. PATIENTS AND METHODS: The expression levels of LINC00665 and miR-3619 were assessed by RT-qPCR. The correlation between LINC00665 and miR-3619 expression was evaluated by Pearson's correlation analysis. The interaction between LINC00665 and miR-3619 was predicted by starBase, which was further confirmed by Luciferase reporter assay and RIP assay. The viability, invasion, and migration of OS cells were analyzed by CCK-8 and transwell assays. RESULTS: LINC00665 expression was upregulated in OS tissues and cell lines, and the high level of LINC00665 was associated with poor prognosis in OS. Moreover, LINC00665 knockdown attenuated the viability, invasion, and migration of OS cells. In addition, miR-3619 was demonstrated to be a target of LINC00665. Overexpression of miR-3619 inhibited OS progression, while this effect was abolished by the upregulation of LINC00665. CONCLUSIONS: We demonstrated that LINC 00665 accelerated OS development by targeting miR-3619. These findings might provide potential treatment strategies for patients with OS.

[Clinical observation of postprandial hypotension in patients with hypertensive and coronary heart disease].

Objective: To explore the prevalence and clinical characteristics of postprandial hypotension(PPH) in patients with essential hypertension and coronary heart disease. Methods: A total of 197 patients with essential hypertension and coronary heart disease, who had been treated in the First Department of Cardiology of the Second Hospital of Hebei Medical University from December, 2013 to December, 2014 were included. The patients' blood pressure before breakfast, lunch and dinner and 30, 60, 90, 120 minutes after the meal were monitored. Subjects were classified into PPH group (n=37) and non-PPH group (NPPH, n=160) according to postprandial decrease in systolic blood pressure, to explore the clinical characteristics and related factors and the major adverse cardiac and cerebral vascular events of PPH. Results: Among 197 patients, 37 cases (18.8%) showed at least once postprandial decline in systolic blood pressure greater than and equal to 20 mmHg. The incidence of PPH after breakfast and dinner were higher than lunch (P<0.05). There was no significant difference in the incidence of PPH among different age groups, among patients accompanied with different diseases, and among patients with different dining position (all P>0.05). According to the baseline systolic blood pressure, patients can be divided into 4 groups(<120 mmHg, 120-129 mmHg, 130-139 mmHg, >140 mmHg), the higher the level of the baseline systolic blood pressure was, the higher the incidence of PPH was. And the incidence of major adverse cardiac and cerebral vascular events in patients during hospitalization were increased by PPH. Conclusions: The prevalence of PPH in the patients with essential hypertension and coronary heart disease is 18.8%. The incidence of PPH after breakfast and dinner is higher than lunch. The baseline systolic blood pressure is considered to be the risk factor of PPH. And PPH could lead to an increase of the incidence of major adverse cardiac and cerebral vascular events.

Suppressing turbulence and enhancing liquid suspension flow in pipelines with electrorheology.

Flows through pipes, such as crude oil through pipelines, are the most common and important method of transportation of fluids. To enhance the flow output along the pipeline requires reducing viscosity and suppressing turbulence simultaneously and effectively. Unfortunately, no method is currently available to accomplish both goals simultaneously. Here we show that electrorheology provides an efficient solution. When a strong electric field is applied along the flow direction in a small section of pipeline, the field polarizes and aggregates the particles suspended inside the base liquid into short chains along the flow direction. Such aggregation breaks the rotational symmetry and makes the fluid viscosity anisotropic. In the directions perpendicular to the flow, the viscosity is substantially increased, effectively suppressing the turbulence. Along the flow direction, the viscosity is significantly reduced; thus the flow along the pipeline is enhanced. Recent field tests with a crude oil pipeline fully confirm the theoretical results.

Electrokinetic behavior of two touching inhomogeneous biological cells and colloidal particles: effects of multipolar interactions.

We present a theory to investigate electrokinetic behavior, namely, electrorotation and dielectrophoresis under alternating current (ac) applied fields for a pair of touching inhomogeneous colloidal particles and biological cells. These inhomogeneous particles are treated as graded ones with physically motivated model dielectric and conductivity profiles. The mutual polarization interaction between the particles yields a change in their respective dipole moments, and hence in the ac electrokinetic spectra. The multipolar interactions between polarized particles are accurately captured by the multiple images method. In the point-dipole limit, our theory reproduces the known results. We find that the multipolar interactions as well as the spatial fluctuations inside the particles can affect the ac electrokinetic spectra significantly.

Nonlinear alternating current responses of graded materials.

When a composite of nonlinear particles suspended in a host medium is subjected to a sinusoidal electric field, the electrical response in the composite will generally consist of alternating current (ac) fields at frequencies of higher-order harmonics. The situation becomes more interesting when the suspended particles are graded, with a spatial variation in the dielectric properties. The local electric field inside the graded particles can be calculated by the differential effective dipole approximation, which agrees very well with a first-principles approach. In this work, a nonlinear differential effective dipole approximation and a perturbation expansion method have been employed to investigate the effect of gradation on the nonlinear ac responses of these composites. The results showed that the fundamental and third-harmonic ac responses are sensitive to the dielectric-constant and/or nonlinear-susceptibility gradation profiles within the particles. Thus, by measuring the ac responses of the graded composites, it is possible to perform a real-time monitoring of the fabrication process of the gradation profiles within the graded particles.

Electrorotation in graded colloidal suspensions.

Biological cells can be treated as composites of graded material inclusions. In addition to biomaterials, graded composites are important in more traditional materials science. In this paper, we investigate the electrorotation spectrum of a graded colloidal suspension in an attempt to discuss its dielectric properties. For that, we use the recently obtained differential effective dipole approximation and generalize it for nonspherical particles. We find that variations in the conductivity profile may make the characteristic frequency redshifted and have also an effect on the rotation peak. On the other hand, variations in the dielectric profile may enhance the rotation peak, but do not have any significant effect on the characteristic frequency. In the end, we apply our theory to fit experimental data obtained for yeast cells and find good agreement.

Electrorotation of a pair of spherical particles.

We present a theoretical study of electrorotation (ER) of two spherical particles under the action of a rotating electric field. When the two particles approach and finally touch, the mutual polarization interaction between the particles leads to a change in the dipole moment of the individual particle and hence the ER spectrum, as compared to that of the well-separated particles. The mutual polarization effects are captured by the method of multiple images. From the theoretical analysis, we find that the mutual polarization effects can change the characteristic frequency at which the maximum angular velocity of electrorotation occurs. The numerical results can be understood in the spectral representation theory.

Relaxation of surface charge on rotating dielectric spheres: Implications on dynamic electrorheological effects.

We have examined the effect of an oscillatory rotation of a polarized dielectric particle. The rotational motion leads to a redistribution of the polarization charge on the surface of the particle. We show that the time-averaged steady-state dipole moment is along the field direction, but its magnitude is reduced by a factor that depends on the angular velocity of rotation. As a result, the rotational motion of the particle reduces the electrorheological effect. We further assume that the relaxation of the polarized charge is arised from a finite conductivity of the particle or host medium. We calculate the relaxation time based on the Maxwell-Wagner theory, suitably generalized to include the rotational motion. Analytic expressions for the reduction factor and the relaxation time are given and their dependence on the angular velocity of rotation will be discussed.

Nonlinear ac response of an electrorheological fluid.

The applied electric field used in most electrorheological (ER) experiments is usually quite high, and nonlinear ER effects have been measured recently. When a nonlinear ER fluid is subjected to a sinusoidal (ac) field, the electrical response will in general consist of ac fields at frequencies of the higher-order harmonics. In this paper, a self-consistent formalism has been employed to compute the induced dipole moment for ER fluids in which the suspended particles have nonlinear characteristics, in an attempt to investigate the ac response of a nonlinear ER fluid.