Anomalous polarization-sensitive Fabry-Perot resonance in a one-dimensional photonic crystal containing an all-dielectric metamaterial defect.

Owing to polarization-independent property of propagating phases inside isotropic dielectric layers, Fabry-Perot resonances in metal-dielectric-metal sandwich structures and one-dimensional (1-D) photonic crystals (PhCs) with isotropic dielectric defects are polarization-insensitive. Herein, we introduce an all-dielectric elliptical metamaterial (EMM) defect into a 1-D PhC to realize an anomalous polarization-sensitive Fabry-Perot resonance empowered by the polarization-sensitive property of the propagating phase inside the all-dielectric EMM layer. The wavelength difference of the Fabry-Perot resonance between transverse magnetic and transverse electric polarizations is larger than 100 nm at the incident angle of 45 degrees. Enabled by the polarization-sensitive property of the Fabry-Perot resonance, high-performance polarization selectivity can be achieved in a broad angle range. Our work offers a viable recipe, well within the reach of current fabrication technique, to explore polarization-dependent physical phenomena and devices.

Anomalous polarization-sensitive Fabry-Perot resonance in a one-dimensional photonic crystal containing an all-dielectric metamaterial defect: erratum.

This erratum corrects some typing errors of our original paper, Opt. Express31(20), 32669 (2023)10.1364/OE.499830. The correction does not affect the results of the original paper.

Ultra-large near-infrared omnidirectional photonic bandgaps in cascaded one-dimensional photonic crystals containing all-dielectric metamaterials.

In conventional one-dimensional (1-D) photonic crystals (PCs) consisting of isotropic dielectrics, photonic bandgaps (PBGs) substantially shift toward shorter wavelengths as incident angle increases. This strong blueshift characteristic of PBGs significantly reduces the widths of near-infrared omnidirectional photonic bandgaps (OPBGs). Recently, researchers achieved a kind of special PBG called angle-insensitive PBGs in 1-D PCs containing all-dielectric elliptical metamaterials (EMMs). The emergence of angle-insensitive PBGs provides us a possibility to achieve ultra-large near-infrared OPBGs. Herein, we design two 1-D PCs containing all-dielectric EMMs with near-infrared angle-insensitive PBGs in different wavelength ranges. By cascading two 1-D PCs containing all-dielectric EMMs together, we achieve an ultra-large near-infrared OPBG with a width up to 1.004 µm (relative bandwidth of 63.9%). In addition, the width of the near-infrared OPBG demonstrates robustness against the layer thickness. Our work not only provides a feasible route to achieving ultra-large near-infrared OPBGs, but also facilitates the design of broadband omnidirectional mirrors.

Emerging microfluidic gut-on-a-chip systems for drug development.

The gut is a vital organ that is central to the absorption and metabolic processing of orally administered drugs. While there have been many models developed with the goal of studying the absorption of drugs in the gut, these models fail to adequately recapitulate the diverse, complex gastrointestinal microenvironment. The recent emergence of microfluidic organ-on-a-chip technologies has provided a novel means of modeling the gut, yielding radical new insights into the structure of the gut and the mechanisms through which it shapes disease, with key implications for biomedical developmental efforts. Such organ-on-a-chip technologies have been demonstrated to exhibit greater cost-effectiveness, fewer ethical concerns, and a better ability to address inter-species differences in traditional animal models in the context of drug development. The present review offers an overview of recent developments in the reconstruction of gut structure and function in vitro using microfluidic gut-on-a-chip (GOC) systems, together with a discussion of the potential applications of these platforms in the context of drug development and the challenges and future prospects associated with this technology. STATEMENT OF SIGNIFICANCE: This paper outlines the characteristics of the different cell types most frequently used to construct microfluidic gut-on-a-chip models and the microfluidic devices employed for the study of drug absorption. And the applications of gut-related multichip coupling and disease modelling in the context of drug development is systematically reviewed. With the detailed summarization of microfluidic chip-based gut models and discussion of the prospective directions for practical application, this review will provide insights to the innovative design and application of microfluidic gut-on-a-chip for drug development.

[Neonatal intrahepatic cholestasis caused by citrin deficiency: a histopathologic study of 10 cases].

OBJECTIVE: To investigate the diagnostic value of histopathological changes in the liver of patients with neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD). METHODS: Liver specimens from 10 cases of NICCD were evaluated by hematoxylin-eosin stain, histochemistry and immunohistochemistry (EnVision method). SLC25A13 mutation analysis was performed to correlate with histopathology. RESULTS: Most specimens showed varying degrees of fat deposition in hepatocytes, necrotic inflammation, cholestasis and fibrosis (so-called tetralogy). The combination of the above four histological changes was highly characteristic for NICCD. With the progression of the disease, hepatic fibrosis deteriorated and ultimately led to cirrhosis. CONCLUSIONS: NICCD should be suspected in the presence of cholestasis during infancy. A liver biopsy must be performed to rule out other liver diseases. The tetralogy of the hepatic histopathological changes has a highly diagnostic value for NICCD, which is also practical for accurately assessing the degree of inflammation and fibrosis, and similarly the progression of hepatic cirrhosis.

Inhibition of signal transducer and activator of transcription 3 expression by RNA interference suppresses invasion through inducing anoikis in human colon cancer cells.

AIM: To investigate the roles and mechanism of signal transducer and activator of transcription 3 (STAT3) in invasion of human colon cancer cells by RNA interference. METHODS: Small interfering RNA (siRNA) targeting Signal transducer and activator of transcription 3 (STAT3) was transfected into HT29 colon cancer cells. STAT3 protein level and DNA-binding activity of STAT3 was evaluated by western blotting and electrophoretic mobility shift assay (EMSA), respectively. We studied the anchorage-independent growth using colony formation in soft agar, and invasion using the boyden chamber model, anoikis using DNA fragmentation assay and terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL), respectively. Western blot assay was used to observe the protein expression of Bcl-xL and survivin in colon cancer HT29 cells. RESULTS: RNA interference (RNAi) mediated by siRNA leads to suppression of STAT3 expression in colon cancer cell lines. Suppression of STAT3 expression by siRNA could inhibit anchorage-independent growth, and invasion ability, and induces anoikis in the colon cancer cell line HT29. It has been shown that knockdown of STAT3 expression by siRNA results in a reduction in expression of Bcl-xL and survivin in HT29 cells. CONCLUSION: These results suggest that STAT3 siRNA can inhibit the invasion ability of colon cancer cells through inducing anoikis, which antiapoptotic genes survivin and Bcl-xL contribute to regulation of anoikis. These studies indicate STAT3 siRNA could be a useful therapeutic tool for the treatment of colon cancer.