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The aim of the study is to investigate the effects of sub-chronic poisoning with arsenic on the testes of chickens treated. Seventy-two 1-day-old chickens were randomly divided into 4 groups and provided food with different doses arsenic. The histological changes were examined. The mRNA levels of inflammatory factors, including transcription factor nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), prostaglandin E synthase (PTGEs), and heat shock proteins (Hsps), including Hsp70, Hsp90, Hsp60, Hsp40, and Hsp27 were assessed by quantitative real-time PCR in the testes of chickens. The protein expressions of iNOS, Hsp60, and Hsp70 were detected by western blot. Increased mRNA and protein levels of inflammatory factors and Hsps with testicular damage showed that arsenic-induced testicular toxicity includes inflammatory and heat shock response in chickens, and that increased Hsps levels may play a protective role in inflammation damage induced by arsenic on the testes of chickens. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) were chemically modified by a series of binuclear hexamino-metallo (M2Pc2) which were produced by reducing the corresponding binuclear hexanitro-metallophthalocyanines (M2HnPc2) (M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II)). The compounds were characterized with different techniques: IR, UV-vis, XRD, SEM, XPS. The electrocatalytic performances of the CNTs bonding with M2Pc2 (M2Pc2-CNTs) to Li/SOCl2 battery was tested by adding these compounds into the electrolyte. The capacities of the battery were improved, with increases by 59.1-128.5%. In addition, sequence of the electrochemical catalytic performance of M2Pc2-CNTs is as follow: Fe > Co > Cu > Zn > Ni > Mn. The CNTs bonding with M2Pc2 can greatly promote the electronic transmission, which significantly improve the performance and the initial voltage of Li/SOCl2 battery. Cyclic voltammetry measurements are applied to verify the M2Pc2-CNTs possessing catalytic performances and a reasonable mechanism is proposed. [ABSTRACT FROM AUTHOR]

To understand the characteristics of atmospheric pollution in Xi'an, China, the vertical structure of aerosols and meteorological data (temperature and relative humidity) during atmospheric pollution processes were obtained and studied. Lidar and radiosonde data were used for analyses of atmospheric pollution. Polarization lidar was used to study the vertical distribution and optical properties of aerosols during haze and dust processes that occurred in 2015–2016. The planetary boundary layer height (PBLH) and types of aerosol particles were retrieved from polarization lidar. A case study shows that a low PBLH and complex vertical distributions of aerosols, temperature and relative humidity (RH) were the main structural characteristics of haze days. The backscatter coefficient exceeded 0.015 km−1·Sr−1, while the linear particle depolarization ratio was relatively small. A large depolarization ratio above the haze layer, which induces the existence of floating dust, was observed by polarization lidar. Compared with those of haze processes, the vertical aerosol and temperature distributions of dust processes were different. Statistical analyses of the PBLH, temperature inversion, RH and near-surface aerosol concentration were also presented. A lower PBLH, lower average lapse rate of temperature within the PBL, and higher RH were found when haze pollution occurred. An inversion at the top of the boundary layer aggravates ground pollution, while there is not always a temperature inversion when haze occurs in Xi'an. Together, a lower PBLH and lower average lapse rate of temperature weaken the vertical diffusion of pollutants. Decreased vertical diffusion should be the main reason for the formation and persistence of pollution in Xi'an. Increased RH was the catalyst for haze pollution. The aggravation of haze was usually accompanied by an increase in RH, and the decline of haze processes was also accompanied by a decrease or increase (>90%) in RH. • The simultaneous observations of aerosols and meteorological factors profiles in Xi' an, were performed. • The complex vertical distributions of aerosol, temperature and relative humidity were found in pollution process. • Little average lapse rate of temperature is the main reason for the decrease of vertical diffusion ability of pollutants. [ABSTRACT FROM AUTHOR]

We used a combination of polarized Raman spectroscopy and spin wave calculations to study magnetic excitations in the strong spin-orbit-coupled bilayer perovskite antiferromagnet Sr3Ir2O7. We observed two broad Raman features at ∼800 and ∼1400 cm-1 arising from magnetic excitations. Unconventionally, the ∼800 cm-1 feature is fully symmetric (A1g) with respect to the underlying tetragonal (D4h) crystal lattice which, together with its broad line shape, definitively rules out the possibility of a single magnon excitation as its origin. In contrast, the ∼1400 cm-1 feature shows up in both the A1g and B2g channels. From spin wave and two-magnon scattering cross-section calculations of a tetragonal bilayer antiferromagnet, we identified the ∼800 cm-1 (1400 cm-1) feature as two-magnon excitations with pairs of magnons from the zone-center Γ point (zone-boundary van Hove singularity X point). We further found that this zone-center two-magnon scattering is unique to bilayer perovskite magnets which host an optical branch in addition to the acoustic branch, as compared to their single layer counterparts. This zone-center two-magnon mode is distinct in symmetry from the time-reversal symmetry broken "spin wave gap" and "phase mode" proposed to explain the ∼92 meV (742 cm-1) gap in resonant inelastic x-ray spectroscopy magnetic excitation spectra of Sr3Ir2O7. [ABSTRACT FROM AUTHOR]

We conduct a comprehensive study of three different magnetic semiconductors, CrI3, CrBr3, and CrCl3, by incorporating both fewlayer and bilayer samples in van derWaals tunnel junctions. We find that the interlayer magnetic ordering, exchange gap, magnetic anisotropy, and magnon excitations evolve systematically with changing halogen atom. By fitting to a spin wave theory that accounts for nearest-neighbor exchange interactions, we are able to further determine a simple spin Hamiltonian describing all three systems. These results extend the 2D magnetism platform to Ising, Heisenberg, and XY spin classes in a single material family. Using magneto-optical measurements, we additionally demonstrate that ferromagnetism can be stabilized down to monolayer in more isotropic CrBr3,with transition temperature still close to that of the bulk. [ABSTRACT FROM AUTHOR]

The article reports that the development of novel polymer electrolyte membranes (PEMs) with dense structure, good mechanical flexibility, and high proton conductivity, but with little or no dependence on humidity at temperatures above 100 degree Celsius, remains an important challenge to the realization of practical PEM fuel cells. To date, however, the application of these membranes in fuel cells is still problematic because of their low proton conductivity or inadequate stability under practical fuel cell operating conditions. The introduction of imidazole has generated much excitement in recent years with the hope that the investigations of imidazole-based polymer electrolytes may lead to PEMs with high proton conductivity, good mechanical properties, and long-term stabilities.

Adriamycin (ADM) has been effective against many types of solid tumors in clinical applications. However, its use is limited because of systemic toxicities, primarily cardiotoxicity, and multidrug resistance. In this study, a new active receptor-mediated complex, ADM conjugated with 2-amino-2-deoxy-D-glucose and succinic acid (2DG-SUC-ADM), was designed to target tumor cells through glucose transporter 1 (GLUT1). MTT assay and confocal images showed that the complex had better inhibition rate to tumor cells and low toxicity to normal cells. Most importantly, the complex displayed a potential to reverse overcome multidrug resistance in cancer cells, with more complex transported into the nucleus of tumor cells. Our in vivo experiments also showed that this new complex could significantly decrease organ toxicity and enhance the antitumor efficacy compared with free ADM, indicating a promising drug of 2DG-SUC-ADM for targeted cancer therapy. [ABSTRACT FROM AUTHOR]

Lidar is an active remote sensing instrument, and it has been widely used in the detection of atmospheric environmental parameters and meteorological parameters. In recent years, climate change has been widely concerned by the public, and the corresponding atmospheric detection technology has also been developed rapidly. Atmospheric Lidar has been developed rapidly in China, and has achieved good research achievements. The research progress and development status of Lidar for atmospheric detection in recent years are introduced and summarized in this invited paper. The advantages and disadvantages of all kinds of atmospheric detection Lidars and their applications in different detection objects are comprehensively introduced in this article. Finally, the bottlenecks of Lidar technology are summarized, and the development trend of Lidar is also prospected. [ABSTRACT FROM AUTHOR]

Resistance to TGF-β-induced growth repression is prevalent in various cancer cells, but the underlying mechanisms remain unclear. In this study, we showed that activation of TGF-β signaling caused Sma- and Mad-related family (Smad) 2 and Smad3 to bind directly to the promoter region of miR-195, and then activated miR-195 transcription in normal hepatocytes. Conversely, miR-195 inhibited the expression of Smad7 by binding to its 3'-UTR, thereby strengthening TGF-β-Smad signaling. These data identify a novel TGF-β-miR-195 positive regulatory circuitry in normal hepatocytes. Further investigation revealed that HDAC1, a histone deacetylase that was abnormally overexpressed in hepatocellular carcinoma, could bind to the miR-195 promoter via Smad3 and cause hypoacetylation in the histones associated with the miR-195 promoter in hepatoma cells. This resulted in transcriptional repression of miR-195 and, subsequently, disruption of the TGF-β-miR-195 regulatory loop and evasion of TGF-β-mediated growth inhibition. Moreover, silencing HDAC1 in hepatoma cells restored TGF-β-mediated growth suppression, but this effect was attenuated if miR-195 expression decreased. These findings suggest that HDAC1-induced miR-195 down-regulation is an important mechanism for tumor cells to resist the cytostatic activity of TGF-β, and highlight the importance of TGF-β-Smad2/3-miR-195-Smad7 circuitry in preventing uncontrolled cell proliferation.--Wang, R., Fu, T., You, K., Li, S., Zhao, N., Yang, J., Zhuang, S.-M. Identification of a TGF-β-miR-195 positive feedback loop in hepatocytes and its deregulation in hepatoma cells. [ABSTRACT FROM AUTHOR]

Background: The heavy metal arsenic is widely distributed in nature and posses a serious threat to organism's health. However, little is known about the arsenic-induced inflammatory response in the brain tissues of birds and the relationship and mechanism of the inflammatory response. The purpose of this study was to explore the effects of dietary arsenic on the expression of inflammatory cytokines in the brains of Gallus gallus. Results: Seventy-two 1-day-old male Hy-line chickens were divided into a control group, a low arsenic trioxide (As2O3)-treated (7.5 mg/kg) group, a middle As2O3-treated (15 mg/kg) group, and a high As2O3-treated (30 mg/kg) group. Arsenic exposure caused obvious ultrastructural changes. The mRNA levels of the transcription factor nuclear factor-κB (NF-κB) and of pro-inflammatory cytokines, including inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and prostaglandin E synthase (PTGEs), in chicken brain tissues (cerebrum, cerebellum, thalamus, brainstem and myelencephalon) on days 30, 60 and 90, respectively, were measured by real-time PCR. The protein expression of iNOS was detected by western blot. The results showed that after being treated with As2O3, the levels of inflammatory-related factor NF-κB and pro-inflammatory cytokines in chicken brain tissues increased (P < 0.05). Conclusions: Arsenic exposure in the chickens triggered host defence and induced an inflammatory response by regulating the expression of inflammatory-related genes in the cerebrum, cerebellum, thalamus, brainstem and myelencephalon. These data form a foundation for further research on arsenic-induced neurotoxicity in Gallus gallus. [ABSTRACT FROM AUTHOR]

P-glycoprotein (P-gp), aprognostic indicator for chemotherapy failure, is encoded by multidrug resistance gene (MDR1). MDR1 mRNA expression could serve as a guidance for personalized medicine. However, the traditional PCR process for mRNA measurement is complicated and cannot realize the real-time detection of mRNA in living single cells. In this work, optimized gold nanoparticle-based molecular beacons were employed to determine MDR1 mRNA levels in living cancer cells. To improve detection sensitivity, ultrasound (US) irradiation was applied to facilitate and enhance cellular uptake of hairpin DNA-coated gold nanoparticle (hDAuNP). The US conditions including irradiation power, exposure time, duty cycle, and incubation time were optimized. The slight difference in MDR1 expression manipulated by siRNA silence could be recognized by US assisted hDAuNP beacons; a 10-fold increase of detection sensitivity was achieved compared with the nonultrasound assistance. Meanwhile, the detection cycle could be shortened from 12 to 2 h. Furthermore, this hDAuNP beacon can serve as an antisense agent to down-regulate P-gp expression and to reverse drug resistance of MCF-7/Adr cells to doxorubicin. Our results demonstrated that the MDR1 hDAuNP beacon assisted by US irradiation had great potential to predict chemotherapy sensitivity and to overcome multidrug resistance in cancer cells and was thus a promising tool for individualized medicine. [ABSTRACT FROM AUTHOR]

Abstract: The therapeutic effects of artesunate against experimental Schistosoma mansoni infection in mice were analyzed. Previous studies showed that artesunate is highly effective against S. japonicum infection, but the action of this drug against S. mansoni remained uncovered. The present study examines the optical conditions for artesunate against S. mansoni and evaluates the effects of inhibiting the sexual maturation of adult worms. Mice infected with S. mansoni were orally administered with artesunate according to different schedules. Four consecutive administrations of 300 mg/kg of artesunate at 2-week intervals conferred almost total protection without the development of pathological lesions in the liver. The significant reduction in the number of eggs produced by surviving worms and the status of egg maturation suggested that artesunate inhibits sexual maturation. Electron microscopy revealed that artesunate caused morphological damage, especially on the worm tegument. Artesunate was also very effective in iron-deficient mice. Furthermore, the efficacy of artesunate was equal to or better than that of artemether against S. japonicum infection. Considering that artemether is more toxic, artesunate is currently one of the most efficient drugs against immature S. mansoni. [Copyright &y& Elsevier]

Hartree−Fock ab initio and density functional theory calculations suggest that intra- and intermolecular proton transfer between neutral and protonated triazole tautomers play a vital role in the observed dramatic proton conduction in triazole-based polymer electrolyte membranes. [ABSTRACT FROM AUTHOR]