Temporal Properties of the Compressible Magnetohydrodynamic Turbulence

The temporal property of the compressible magneto-hydrodynamic (MHD) turbulence remains a fundamental unsolved question. Recent studies based on the spatial-temporal analysis in the global frame of reference suggest that the majority of fluctuation power in turbulence does not follow any of the MHD wave dispersion relations but has very low temporal frequency with finite wavenumbers. Here, we demonstrate that the Lorentzian broadening of the dispersion relations of the three MHD modes where the nonlinear effects act like the damping of a harmonic oscillator can explain many salient features of frequency spectra for all MHD modes. The low frequency fluctuations are dominated by modes with the low parallel wavenumbers that have been broadened by the nonlinear processes. The Lorentzian broadening widths of the three MHD modes exhibit scaling relations to the global frame wavenumbers and are intrinsically related to energy cascade of each mode. Our results provide a new window to investigate the temporal properties of turbulence which offers insights for building a comprehensive understanding of the compressible MHD turbulence.Comment: 15 pages, 4 figures, submitte

A preliminary study of in vitro and in vivo synergistic effects of ciprofloxacin and D-tyrosine against Pseudomonas aeruginosa isolates

Purpose: To investigate the synergistic antimicrobial effects of ciprofloxacin and D-tyrosine against drug-resistant bacteria.Method: The antimicrobial effects of ciprofloxacin and D-tyrosine on clinical isolates of multidrugresistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) no. 3556 were determined in vitro based on time-kill curve, and in vivo in P. aeruginosa-zebrafish infection model. Furthermore, 30 clinical isolates of multidrug-resistant P. aeruginosa were used in vitro to ascertain the synergistic effect of the two agents.Results: Combined use of ciprofloxacin and D-tyrosine produced synergistic effects against the clinical isolate of P. aeruginosa no. 3556 in vitro and in vivo. Synergism occurred in 96.67 % (95 % CI, range 83.33 - 99.41 %) of the clinical isolates, and ciprofloxacin dose was reduced in 90 % (95 % CI, range 74.38 - 96.54 %) of the clinical isolates in vitro.Conclusion: These preliminary results suggest that the combination of ciprofloxacin and D-tyrosine is a promising therapeutic strategy against MDR P. aeruginosa infections. Keywords: Ciprofloxacin, D-tyrosine, Synergistic, P. aeruginosa, Zebrafish infection model, Time-killing curv

Effects of prolonging administration gonadotropin on unexpectedly poor ovarian responders undergoing in vitro fertilization

<p>Abstract</p> <p>Background</p> <p>There are still some patients who show poor response to ovarian stimulation prior to evidence of normal ovarian reserve in vitro fertilization. However, there are few studies about how to treat the unexpectedly ovarian poor responder in vitro fertilization. The main aim of this study evaluate the effect of prolonging administration follicle-stimulating hormone in woman with the unexpectedly ovarian poor responder in vitro fertilization on implantation rate, clinical pregnancy rate and live birth rate.</p> <p>Methods</p> <p>922 patients subjected to IVF were divided into two groups according to the predicted criterion of ovarian poor response. 116 patients predicted poor response received the short protocol (group C). The others received the long protocol, among the latter, there were 149 patients undergoing unexpectedly ovarian poor response (group B) and 657 patients exhibited normal ovarian response (group A). The doses of gonadotropin, duration of administration, implantation rate, clinical pregnancy rate and live birth rate were recorded among three groups.</p> <p>Results</p> <p>The implantation rate of embryo, clinic pregnancy rate and delivery rate are similar between the group A and group B, while there are significant differences between the doses of gonadotropins (35.1 +/- 8.9 ampules vs.53.0 +/- 15.9 ampules) and the duration of administration (15.3 +/- 3.6D vs. 9.8 +/- 2.6D) of these two groups. There are no significant differences about clinical pregnancy rate and live birth rate between group B and group C.</p> <p>Conclusion</p> <p>Prolonging administration gonadotropin on the unexpectedly poor ovarian responders does not lower live birth rate in vitro fertilization.</p

Cynaropicrin inhibits lung cancer proliferation by targeting EGFR/AKT signaling pathway

Purpose: To investigate the anti-proliferative effect of cynaropicrin on lung cancer cell lines, and the underlying molecular mechanism. Methods: The effect of cynaropicrin treatment on the viabilities of H1975 and H460 cells was measured using Cell Counting Kit-8. Apoptosis was analysed by annexin-V/FITC staining, while protein expressions were assayed by western blotting. Results: Treatment of H1975 and H460 cells with cynaropicrin at doses of 0.25 – 2.0 μM led to a marked reduction in their viability (p &lt; 0.05). In cynaropicrin-treated H1975 and H460 cells, there was significant increase in apoptosis, when compared to control cells. Caspase-3 and caspase-9 levels were also significantly increased in H1975 and H460 cells on treatment with cynaropicrin at doses of 0.25 and 2.0 μM while treatment with cynaropicrin at doses of 0.25 - 2.0 μM significantly down-regulated the mRNA expression of CCND1 in the two cell lines (p &lt; 0.05). Cynaropicrin markedly inhibited mRNA and protein expressions of EGFR, and also downregulated AKT in H1975 and H460 cells (p &lt; 0.05). However, cynaropicrin significantly increased the expressions of miR-202 and miR-370. Conclusion: Cynaropicrin exerts anti-proliferative and proapoptotic effects on H1975 and H460 lung cancer cells via deactivation of EGFR/AKT signaling pathway. Moreover, it upregulated the expressions of miR-202 and miR-370 in these cells. Thus, cynaropicrin has potentials for the treatment of lung cancer

Cosmic Ray streaming from SNRs and gamma ray emission from nearby molecular clouds

High-energy gamma ray emission has been detected recently from supernovae remnants (SNRs) and their surroundings. The existence of molecular clouds near some of the SNRs suggests that the gamma rays originate predominantly from p-p interactions with cosmic rays accelerated at a closeby SNR shock wave. Here we investigate the acceleration of cosmic rays and the gamma ray production in the cloud self-consistently by taking into account the interactions of the streaming instability and the background turbulence both at the shock front and in the ensuing propagation to the clouds. We focus on the later evolution of SNRs, when the conventional treatment of the streaming instability is valid but the magnetic field is enhanced due to either Bell's current instability and/or due to the dynamo generation of magnetic field in the precursor region. We calculate the time dependence of the maximum energy of the accelerated particles. This result is then used to determine the diffusive flux of the runaway particles escaping the shock region, from which we obtain the gamma spectrum consistent with observations. Finally, we check the self-consistency of our results by comparing the required level of diffusion with the level of the streaming instability attainable in the presence of turbulence damping. The energy range of cosmic rays subject to the streaming instability is able to produce the observed energy spectrum of gamma rays.Comment: 7 pages, 4 figures, ApJ in pres

Preparation and biological activity of the monoclonal antibody against the second extracellular loop of the angiotensin II type 1 receptor

The current study was to prepare a mouse-derived antibody against the angiotensin II type 1 receptor (AT1-mAb) based on monoclonal antibody technology, to provide a foundation for research on AT1-AA-positive diseases. Balb/C mice were actively immunized with the second extracellular loop of the angiotensin II type 1 receptor (AT1R-ECII). Then, mouse spleen lymphocytes were fused with myeloma cells and monoclonal hybridomas that secreted AT1-mAb were generated and cultured, after which those in logarithmic-phase were injected into the abdominal cavity of mice to retrieve the ascites. Highly purified AT1-mAb was isolated from mouse ascites after injection with 1 × 107 hybridomas. A greater amount of AT1-mAb was purified from mouse ascites compared to the cell supernatant of hybridomas. AT1-mAb purified from mouse ascites constricted the thoracic aorta of mice and increased the beat frequency of neonatal rat myocardial cells via the AT1R, identical to the effects of AT1-AA extracted from patients’ sera. Murine blood pressure increased after intravenous injection of AT1-mAb via the tail vein. High purity and good biological activity of AT1-mAb can be obtained from mouse ascites after intraperitoneal injection of monoclonal hybridomas that secrete AT1-mAb. These data provide a simple tool for studying AT1-AA-positive diseases