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Worldwide, colorectal cancer (CRC) is one of the most common malignant tumors, leading to immense social and economic burdens. Currently, the main treatments for CRC include surgery, chemotherapy, radiotherapy and immunotherapy. Despite advances in the diagnosis and treatment of CRC, the prognosis for CRC patients remains poor. Furthermore, the occurrence of side effects and toxicities severely limits the clinical use of these therapies. Therefore, alternative medications with high efficacy but few side effects are needed. An increasing number of modern pharmacological studies and clinical trials have supported the effectiveness of Chinese herbal medicines (CHMs) for the prevention and treatment of CRC. CHMs may be able to effectively reduce the risk of CRC, alleviate the adverse reactions caused by chemotherapy, and prolong the survival time of patients with advanced CRC. Studies of molecular mechanisms have provided deeper insight into the roles of molecules from CHMs in treating CRC. This paper summarizes the current understanding of the use of CHMs for the prevention and treatment of CRC, the main molecular mechanisms involved in these processes, the role of CHMs in modulating chemotherapy-induced adverse reactions, and CHM's potential role in epigenetic regulation of CRC. The current study provides beneficial information on the use of CHMs for the prevention and treatment of CRC in the clinic, and suggests novel directions for new drug discovery against CRC.

Antibiotic resistance has become an important focus of research in the aquaculture environment. However, few studies have evaluated antibiotic resistance during the seedling period in marine fish cage-culture areas. In this study, culture-dependent methods and quantitative polymerase chain reaction were used to identify and detect cultivable heterotrophic antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs), respectively, during the seedling period in a marine fish cage-culture areas of Hainan, China. Bacterial resistance to amoxicillin, erythromycin, and gentamicin was generally high (average on 27.67%, 23.61% and 37.32%, respectively), whereas resistance to furazolidone and nitrofurantoin was generally low (average on 0.14% and 7.425%). Alteromonas (32.72%) and Vibrio (24.77%) were the dominant genus of ARB. Most ARB were opportunistic pathogens, belonging to the phylum Proteobacteria (96.02%). The abundance of sul family genes was higher than that of tet family genes. Overall, the abundance of ARGs and the resistance rates in HW was highest.

The thermal insulation performance of cubic ZrO2–CaO solid solution (CSZ) (16 mol % CaO) and monoclinic ZrO2 (MZ) was investigated in a two-stage multi-anvil press under a pressure of 10 GPa and te...

// Yunli Tong 1, 2, * , Yuting Liu 1, 2, * , Hongming Zheng 2 , Liang Zheng 1, 2 , Wenqin Liu 1, 2 , Jinjun Wu 2 , Rilan Ou 2 , Guiyu Zhang 2 , Fangyuan Li 2 , Ming Hu 2, 3 , Zhongqiu Liu 1, 2 , Linlin Lu 2 1 School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China 2 International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, 510006, China 3 Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas, 77030, USA * These authors have contributed equally to this work Correspondence to: Zhongqiu Liu, e-mail: liuzq@gzucm.edu.cn , liuzq@smu.edu.cn Linlin Lu, e-mail: lllu@gzucm.edu.cn Keywords: non-small-cell lung cancer, artemisinin, derivative, Wnt/β-catenin Received: November 16, 2015 Accepted: April 02, 2016 Published: April 22, 2016 ABSTRACT Non-small-cell lung cancer (NSCLC) is the most prevalent malignancy worldwide given its high incidence, considerable mortality, and poor prognosis. The anti-malaria compounds artemisinin (ART), dihydroartemisinin (DHA), and artesunate (ARTS) reportedly have anti-cancer potential, although the underlying mechanisms remain unclear. In this work, we used flow cytometry to show that ART, DHA, and ARTS could inhibit the proliferation of A549 and H1299 cells by arresting cell cycle in G1 phase. Meanwhile, tumor malignancy including migration, invasion, cancer stem cells, and epithelial–mesenchymal transition were also significantly suppressed by these compounds. Furthermore, ART, DHA, and ARTS remarkably decreased tumor growth in vivo . By using IWP-2, the inhibitor of Wnt/β-catenin pathway, and Wnt5a siRNA, we found that ART, DHA, and ARTS could render tumor inhibition partially dependent on Wnt/β-catenin inactivation. These compounds could strikingly decrease the protein level of Wnt5-a/b and simultaneously increase those of NKD2 and Axin2, ultimately resulting in β-catenin downregulation. In summary, our findings revealed that ART, DHA, and ARTS could suppress lung-tumor progression by inhibiting Wnt/β-catenin pathway, thereby suggesting a novel target for ART, DHA, and ARTS in cancer treatment.

The rapid emergence and dissemination of antibiotic resistance poses a threat to human health and to the marine environment. We have investigated the abundance and diversity of antibiotic resistance genes (ARGs) and of antibiotic-resistant bacteria (ARB), during the seedling period, rearing period, and harvesting period in seven marine fish cage-culture areas in Guangdong. Spatial and temporal variations of AGRs and ARB were also analyzed. Culture-based methods and quantitative PCR were used to detect ARB and ARGs. Bacterial resistance rates were no significantly different within farming periods. The proportion of antibiotic-resistant bacteria was extremely low (average on 1.15%), except for oxytetracycline-resistant bacteria (average on 34.15%). Vibrio was the most common ARB. Sul1, tetB, and ermB, had the highest relative abundance. The abundance of ARGs in the harvesting period was significant highest. The total abundance of ARGs was highest at Raoping and lowest at Dayawan and Liusha. Most ARGs were associated with opportunistic pathogens. The environmental factors effecting ARB and ARGs are complex, and no key factors were identified. This study provides a theoretical basis for assessing the harmfulness of ARGs and ARB to food safety and human health.

We propose the coaxial gold nanotubes for their transmission and plasmon resonances theoretically. We find that the transmission spectra are highly adjustable by tuning the thickness of the nanotubes, the separation and the dielectric constant between the inner and outer nanotubes. The resonance peaks close to the left forbidden band gap edge are strongly correlated with the dielectric constant, the inner and outer tube thickness, and the separation between the two tubes. Based on the localized nature of the electric field distributions, we show that local plasmon resonance modes result from hybridized resonances of multifold multipolar plasmon polaritons in the cross section of the coaxial nanotubes.

The optical properties and plasmon resonances coupling of ordered gold nanoshell arrays are investigated theoretically by means of finite-difference time-domain (FDTD) theory. We showed that the thickness, size and inter-shell distance of the nanoshells can tune the optical transmission of the system and the highly geometry-dependent plasmon response can be seen as an interaction between the essentially fixed-frequency plasmon response of a nanosphere and that of a nanocavity for the nanoshells. We also revealed the two different resonance modes by analyzing the spatial distributions of electric field component Ez. We proposed that the peaks of the lower energy mainly originate from the sphere plasmons coupling and the peaks of the higher energy are mainly attributed to the coupling between the sphere plasmons and the cavity plasmons.

We investigate a periodic slit–groove metal array with converging and diverging shaped channels by using the finite-difference time-domain (FDTD) method. We show that the peaks and dips of the transmission spectra can be tuned by the geometry parameters of the groove. And the resonance modes are strongly correlated with the groove depth and width of both ends of the groove, and the transmission dip between the resonance modes can be modulated by these parameters. However, the distance between the slit and the groove has little influence on the transmission. We show that the periodic slit–groove with diverging and converging shaped channels is useful for the design of plasmonic devices.

The plasmonic properties in coupled metallic nanotube arrays are investigated theoretically by the finite-difference time-domain (FDTD) method. We calculate the transmission spectra and the electric field distributions. We show that there is a photonic band gap over a wide optical wavelength range and the transmission spectrum depends strongly on the inner radii, the separation distance and the number of the nanotubes. Based on the localized nature of the field distribution, we also clearly show that the presence of local plasmon resonant modes that originate from multipolar plasmon polaritons and a big magnitude of opposing surface charges build up in the gap between adjacent nanotubes.

We have theoretically investigated the effect of the dielectric core and the dielectric embedding medium separately on the transmission spectra and plasmonic properties of coupled metallic nanotube arrays. It is found that the plasmonic properties of the nanotube arrays are strongly influenced by the presence of the dielectric which induces additional screening charges. We show that instead of one single photonic bandgap for the hollow nanotube arrays placed in air, an additional photonic bandgap arises from the presence of dielectric media in the transmission spectra. Based on the localized nature of the electric field distributions, we also clearly show the presence of the local plasmonic resonant modes that originate from multipolar plasmon polaritons in the cross section of these nanotube arrays, and that a large amount of opposing surface charges are built up in the gap between adjacent nanotubes.

We investigate numerically the transmittance of light through gold double-layer structures with periodic coaxial and non-coaxial slits. We attribute the enhanced optical transmission to the surface plasmon resonance collaborating with the localized waveguide resonance. The transmission spectra and the surface electric fields are used to characterize the resonances of both types. For the coaxial system, with the increase of the slit width of the second layer, the resonance peak values of both types increase sharply at first until the two layers have the same slit width and then decrease dramatically; additionally, the center of the localized waveguide resonance peak shifts to shorter wavelength noticeably, but the surface plasmon peak center moves negligibly. As regards the non-coaxial structure, it shows a similar behavior of the localized waveguide resonance peak to that of the coaxial one; however, the surface plasmon resonance peak behaves in a different way. These results may be associated with the surface plasmon coupling modes and the Fabry–Perot cavity modes in the double-layer structure.

This paper has made a theoretical study of enhanced transmission through a gold grating with arrays of subwavelength slits filled with nonlinear Kerr medium. The results of the research are based on rigorous finite-difference time domain calculations. The resonance transmission peaks in the investigated wavelength range are produced as a result of the surface plasmon resonance collaborated with the localized waveguide resonance. The paper also gives a detailed analysis of the influence exerted by various factors: thickness, third-order susceptibility and line refractive index of the nonlinear medium filled in the gold slits arrays and the incident intensity to the transmission. It is found that the small changes of parameters such as medium thickness, third-order susceptibility and line refractive index of the nonlinear medium filled in the gold slits arrays as well as the incident intensity can bring great changes of lateral shift and magnitude variation of the transmission resonance peaks. The report proposes that these phenomena can be applied to designing precise optical switches.

We present the numerical investigation of the optical transmission through a periodic gold nanoslit array embedded in the Kerr type nonlinear medium by using a developed two-dimensional Finite Different Time Domain (FDTD) method. The enhanced transmission in the nonlinear structure is attributed to the collaboration of the surface plasmon resonance and the localized waveguide resonance. We show that, in a certain intensity range, with the increase of the incident intensity, the transmission resonance peaks redshift obviously, and peak values decrease firstly and then increase; with the gold film thickness and the embedded depth becoming larger, transmission resonance peaks of both types redshift significantly, and the peak number, peak value and the half peak width change obviously. The electric fields distributions for different embedded depths of the gold slits at various resonance wavelengths are simulated to illuminate the underlying physical mechanisms. It is expected that these results obtained here will help to design nonlinear subwavelength metallic grating devices.

We have numerically simulated the induced electric fields and the plasmonic interactions of a metallic nanotube near a thin metallic film. Our study shows that the energies and intensities of the plasmon resonances depend strongly on the aspect ratio (the ratio of the inner to outer radius) of the nanotube as well as the separation between the center of the nanotube and the upper surface of the metallic film and the thickness of the film. The enhancement of the induced electric field of this system reaches as high as 104 orders of magnitude and its field distribution is characterized by waveguide-mode resonance. The report proposes that these phenomena can be applied to designing surface enhanced spectroscopies such as surface enhanced Raman spectroscopy for efficient chemical and biological sensing.

Internal field-assisted Ag–O–Cs photocathode with sandwich-like structure was successfully fabricated by depositing a silver electrode on the surface of Ag–O–Cs composite thin films that were pre-grown onto a conductive glass substrate. Enhanced photoemission was observed from Ag–O–Cs composite thin films when an internal assistant electric field was applied to the photocathode through the designed sandwich-like structure. The total increase of photoelectronic quantum yield corresponding to the applied 30 V bias was about 15.7% while the photocathode was irradiated by the light with wavelength of 510 nm. Theoretical analysis indicates that such an enhanced photoemission can be attributed to the field-induced variations in the energy-band structure of Ag–O–Cs thin films, including both the decrease of interfacial barrier between the embedded Ag nanoparticles and the CsxO (2≤x

Chuanwu (CW), the mother root ofAconitum carmichaeliiDebx., is a traditional Chinese medicine (TCM) for treating traumatic injuries, rheumatoid arthritis, and tumors. CW coadministered with banxia (BX), the root ofPinellia ternata, is also widely prescribed in clinical practice. However, the mechanism of this combination is yet deciphered. Current study aimed to investigate the effects of CW, including raw chuanwu (RCW) and processed chuanwu (PCW) alone, as well as CW coadministered with BX on CYP3A activity. Buspirone (BP) and testosterone (Tes) were used as specific probe substratesin vivoandex vivo, respectively. CYP3A activity was determined by the metabolites formation ratios from the substrates. Compared with those in the control group, the metabolites formation ratios significantly decreased in the RCW and PCW alone groups, accompanied by a marked decrease in CYP3A protein and mRNA levels. However, there was a significant increase in those ratios in the RCW-BX and PCW-BX groups compared to the RCW and PCW alone groups. The results indicated that both RCW and PCW can inhibit CYP3A activity in rats because of downregulation of CYP3A protein and mRNA levels. Decreases in CYP3A activity can be reversed by coadministration with BX.

The Ag–BaO thin films are a new kind of photoemissive thin films, which have transient optical and ultrafast photoelectronic response. The properties of the Ag–BaO thin films establish the application foundation of detecting ultrashort infrared laser pulses. The measurement of the quantum yield of photoemission for ultrashort laser pulses is different from that for normal visible light. The experimental results present that the quantum yield of Ag–BaO thin films is of the order of magnitude of 10−6 under the action of a single laser pulse when the incident infrared laser wavelength is 1.06 μm. It is two orders of magnitude higher than that of pure metals at the same conditions. The quantum yield under the action of a single-chain laser pulse, which comprises 11 single pulses of duration 40 ps separated by 10 ns, increases rapidly following increasing incident energy of the laser. In this case, the Ag–BaO thin films present multiphoton emission of 2-photon process and higher quantum yield of 10−5.

Ultrathin ZnO nanowires have been fabricated by a vapor-phase transport process via the vapor-liquid-solid mechanism. The average diameter of the nanowires is about only 10 nm and the length is up to several micrometers. The experimental results show that the growth of the nanowires is very sensitive to the temperature, catalyzer materials, the content of oxygen in the carrier gas, and the gas pressure. The diameter of the nanowires is directly determined by the size of eutectic alloy droplets related to the thickness of Au catalyzer film and the gas pressure. Ultrathin ZnO nanowires can only be synthesized at a certain pressure of about 300 Torr and the temperature in the range from 450-500 /spl deg/C when a layer of 20 nm Au catalyzer film is employed. Photoluminescence spectrum of the ultrathin ZnO nanowires is also measured, and an intensive ultraviolet light emission centered at 389 nm has been observed.

We measured the enhancement of photoemission by the application of a high electric field to the surface of Na 2 KSb photocathodes which were stimulated by ultrashort laser pulses (wavelength 1.06 μm or 0.53 μm, pulse duration 50 ps). The gain in photoyield exceeded 5 at a field of 2.7 × 10 7 V/m, and there were steps in the curve of the gain in photoyield versus the applied electric field.