Multifaceted synergistic facilitation mechanism of conductive polymers in promoting selenite bioreduction and biological detoxification.

Here, polypyrrole (PPY) was first used to the bioreduction of toxic selenite, while the acceleration effect and mechanism were explored. Experiment results suggested that PPY could enhance the selenite bioreduction from 0.42 to 1.04 mg/(L·h). The tests of electrochemical analysis and cytochrome c (cyt-c) content confirmed that PPY promoted the intracellular/intracellular electron transfer of Shewanella oneidensis·MR-1 in selenite bioreduction process. The enhancement of metabolic activity by PPY contributed to biological detoxification, which was manifested in the increased extracellular polymeric substances (EPS), adenosine triphosphate (ATP), electron transfer system activity (ETSA), membrane permeability and enzyme activity. Transcriptome analysis of DEGs, KEGG pathway enrichment and GO functional classification verified that the environmental adaptability of Shewanella oneidensis·MR-1 was enhanced with the addition of PPY. The transmission electron microscopy (TEM) images indicated that PPY promoted the biosynthesis of selenium nanoparticles (SeNPs), which was beneficial to reduce cell damage. Combined with the above results, a multifaceted synergistic facilitation mechanism based on "conductive cross-linking network" was elaborated from electron transfer, microbial metabolism and environmental adaptability. This study shed light the effect of conductive polymers (CPs) on selenite bioreduction and provided new insights into the bioremediation of toxic pollutants.

Correction: Best practices in the measurement of circularly polarised photodetectors.

[This corrects the article DOI: 10.1039/D2TC01224C.].

Best practices in the measurement of circularly polarised photodetectors.

Circularly polarised light will revolutionise emerging technologies, including encrypted light-based communications, quantum computing, bioimaging and multi-channel data processing. In order to make use of these remarkable opportunities, high performance photodetectors that can accurately differentiate between left- and right-handed circularly polarised light are desperately needed. Whilst this potential has resulted in considerable research interest in chiral materials and circularly polarised photodetecting devices, their translation into real-world technologies is limited by non-standardised reporting and testing protocols. This mini-review provides an accessible introduction into the working principles of circularly polarised photodetectors and a comprehensive overview of the performance metrics of state-of-the-art devices. We propose a rigorous device characterisation procedure that will allow for standardised evaluation of novel devices, which we hope will accelerate research and investment in this area.

Identification of Diagnostic Biomarkers, Immune Infiltration Characteristics, and Potential Compounds in Rheumatoid Arthritis.

Aims: This study is aimed at investigating the pathogenesis of rheumatoid arthritis (RA) by identifying key biomarkers, associated immune infiltration, and small-molecule compounds using bioinformatic analysis. Methods: Six datasets were obtained from the Gene Expression Omnibus database, and the batch effect was adjusted. Functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to analyse differentially expressed genes (DEGs). Furthermore, candidate small-molecule drugs associated with RA were selected from the Connectivity Map (CMap) database. The least absolute shrinkage and selection operator regression, support vector machine recursive feature elimination, and multivariate logistic regression analyses were performed on DEGs to screen for RA diagnostic markers. The receiver operating characteristic curve, concordance index, and GiViTi calibration band were the metrics used to assess the diagnostic markers of RA identified in this analysis. The single-sample gene set enrichment analysis was performed to calculate the scores of infiltrating immune cells and evaluate the activities of immune-related pathways. Finally, the correlation between screening markers and RA diagnosis was determined. Results: A total of 227 DEGs were identified. Functional enrichment analysis and KEGG revealed that DEGs were enriched by the immune response. CMap analysis identified 11 small-molecule compounds with therapeutic potential for RA. In gene expression, the activities of 13 immune cells and 12 immune-related pathways significantly differed between patients with RA and healthy controls. DPYSL3 and SPP1 had the potential to diagnose RA. SPP1 expression was positively correlated with DPYSL3 in 11 immune cells and 10 immune-related pathways. Conclusion: This study comprehensively analysed DEGs and immune infiltration and screened for potential diagnostic markers and small-molecule compounds of RA.

Induction of COX-2 by feline calicivirus via activation of the MEK1-ERK1/2 pathway, and attenuation of feline lung inflammation and injury by MEK1 inhibitor AZD6244 (selumetinib).

Feline calicivirus (FCV) is an important and highly prevalent pathogen of cats that causes acute infectious respiratory disease. Here it is shown in vitro that FCV induces the production of cyclooxygenase-2 (COX-2) through the MEK1-ERK1/2 signaling pathway. Screening of FCV proteins revealed that FCV non-structural protein VPg enhanced COX-2 mRNA expression and protein production in CRFK cells in a concentration-dependent manner. Regions 24-54aa and 84-111aa in FCV VPg were essential for up-regulation. In vivo, COX-2 and IL-6 production caused by FCV infection of kittens was significantly suppressed by the MEK1 inhibitor AZD6244 (selumetinib) and lung inflammation and injury were practically eliminated, with body temperature being returned to normal. AZD6244 may therefore find application as an effective therapeutic agent for the treatment of FCV infection.

High Responsivity Circular Polarized Light Detectors based on Quasi Two-Dimensional Chiral Perovskite Films.

Circularly polarized light (CPL) has considerable technological potential, from quantum computing to bioimaging. To maximize the opportunity, high performance photodetectors that can directly distinguish left-handed and right-handed circularly polarized light are needed. Hybrid organic-inorganic perovskites containing chiral organic ligands are an emerging candidate for the active material in CPL photodetecting devices, but current studies suggest there to be a trade-off between the ability to differentially absorb CPL and photocurrent responsivity in chiral perovskites devices. Here, we report a CPL detector based on quasi two-dimensional (quasi-2D) chiral perovskite films. We find it is possible to generate materials where the circular dichroism (CD) is comparable in both 2D and quasi-2D films, while the responsivity of the photodetector improves for the latter. Given this, we are able to showcase a CPL photodetector that exhibits both a high dissymmetry factor of 0.15 and a high responsivity of 15.7 A W-1. We believe our data further advocates the potential of chiral perovskites in CPL-dependent photonic technologies.

Efficient and Stable Perovskite Solar Cells with a Superhydrophobic Two-Dimensional Capping Layer.

A two-dimensional (2D) perovskite layer is considered to be a desirable defect passivation structure for the lifelong stability of perovskite solar cells (PSCs). However, the efficiency could be compromised behind the traditional PSCs. Herein, we solve this issue by employing a highly hydrophobic organic cation, 2-[4-(trifluoromethyl)phenyl]ethanamine (CF3-PEA), to form a 2D (CF3-PEA)2PbI4 to effectively passivate the 3D MAPbI3 with fewer defects. The new 2D/3D-structured PSCs show reduced charge recombination, an elongated carrier lifetime, efficient charge generation and transport. Those excellent characters lead to a significant enhancement of the efficiency from 17.9% for pristine PSCs to 21.43% for 2D/3D PSCs. Benefiting from the high hydrophobicity of CF3-PEA, the cells show remarkably improved stability by maintaining 83% of the original efficiency exposed to 80% R.H. and 50 °C for 600 h and 87% under 1 sun illumination for 600 h, which makes our PCSs among the most efficient and stable MAPbI3 solar cells.

Oxymatrine inhibits proliferation and apoptosis of human breast cancer cells through the regulation of miRNA-140-5P.

OBJECTIVE: Oxymatrine has shown strong anti-cancer ability, but its mechanism is not well-studied. METHODS: The inhibitory rates of oxymatrine with various concentrations (0, 1, 2, 4, 6, 8, 16, 32 mg/ml) on MCF-7 cells were detected by CCK-8. The effects of oxymatrine on the expression of miRNA-140-5P in MCF-7 cells were detected by real-time fluorescent quantitative PCR (RT-PCR). miRNA-140-5P mimics or NC mimics were transfected into cells using Lipofectamine 2000. Eventually, the cells were divided into control-group, drug-group, miRNA-140-5P mimics group, NC mimics group, and miRNA-140-5P mimics + drug group. Cell viability was detected by CCK-8 assay and apoptosis rate of each group were measured by using Flow cytometry. Western blot was carried out to detect the protein expression of TGFBR1 and FGF9. RESULTS: Oxymatrine at various concentrations had conspicuous inhibitory effect on the proliferation of MCF-7 cells (P<0.05), and the inhibitory effect of oxymatrine on MCF-7 cells showed both dose- and time-dependent manners. The relative expression of miRNA-140-5P in MCF cells was remarkably lower than that in MCF-10A. Oxymatrine could effectively promote the expression of miRNA-140-5P in MCF-7 cells, and the relative expression of miRNA-140-5P increased significantly with the increased dose of oxymatrine (P<0.05). Both transfection of miRNA-140-5P mimics and oxymatrine treatment could reduce the proliferation of MCF-7 cells (P<0.05), and the proliferation of cells in miRNA-140-5P mimics + drug-group was significantly lower than that of other groups (P<0.05). Compared with the control-group, the protein expressions of TGFbR1 and FGF9 in low-dose, medium-dose and high-dose groups were dramatically decreased (P<0.05), in a dose-dependent manner (P<0.05). CONCLUSION: Oxymatrine inhibits proliferation and promotes cell apoptosis of breast cancer MCF-7 cells. The mechanism may contribute to the regulation of miRNA-140-5p and its target genes.

Fullerene Desymmetrization as a Means to Achieve Single-Enantiomer Electron Acceptors with Maximized Chiroptical Responsiveness.

Solubilized fullerene derivatives have revolutionized the development of organic photovoltaic devices, acting as excellent electron acceptors. The addition of solubilizing addends to the fullerene cage results in a large number of isomers, which are generally employed as isomeric mixtures. Moreover, a significant number of these isomers are chiral, which further adds to the isomeric complexity. The opportunities presented by single-isomer, and particularly single-enantiomer, fullerenes in organic electronic materials and devices are poorly understood however. Here, ten pairs of enantiomers are separated from the 19 structural isomers of bis[60]phenyl-C61-butyric acid methyl ester, using them to elucidate important chiroptical relationships and demonstrating their application to a circularly polarized light (CPL)-detecting device. Larger chiroptical responses are found, occurring through the inherent chirality of the fullerene. When used in a single-enantiomer organic field-effect transistor, the potential to discriminate CPL with a fast light response time and with a very high photocurrent dissymmetry factor (gph  = 1.27 ± 0.06) is demonstrated. This study thus provides key strategies to design fullerenes with large chiroptical responses for use as chiral components of organic electronic devices. It is anticipated that this data will position chiral fullerenes as an exciting material class for the growing field of chiral electronic technologies.

Capillary-written single-crystalline all-inorganic perovskite microribbon arrays for highly-sensitive and thermal-stable photodetectors.

In recent times, as a result of its exceptional resistance to moisture and heat, cesium lead bromide (CsPbBr3) has been established as a potential high-performance perovskite material for optoelectronics, which is inclusive of photodetectors and photovoltaics. It has been demonstrated that a perovskite single crystal has major benefits over its thin-film equivalents; nevertheless, the preparation of perovskite crystal arrays for the utilisation of extensive integration is a challenging task. In this paper, we consider a simple crystallisation system, being a capillary-written system to enable the growth of single crystal microribbon arrays (MRAs) directly from a precursor solution. It is demonstrated by microstructure characterisation that CsPbBr3 MRAs are good-quality single crystals with highly-aligned crystal packing and smooth surfaces. The band-edge photoluminescence (PL) is exceptionally resilient and has a lengthy PL life of ∼62 ns. An exceptional photo-response having a particularly quick 99 µs response time and a 2496 A W-1 ultra-high responsivity is exhibited by photodetectors which are built upon these MRAs. The fact that the as-fabricated photodetectors maintain 90% of their commencing performance following 100 days of constant stress testing under ambient conditions under an illumination of 450 nm, showing exceptional operational stability, is noteworthy. A significant step towards the large-area growth of high-quality perovskite MRAs is presented by this work. This supplies favourable opportunities to build high-performance optoelectronic and nanophotonic systems.

Organic Single-Crystalline p-n Heterojunctions for High-Performance Ambipolar Field-Effect Transistors and Broadband Photodetectors.

Organic semiconducting single crystals are ideal building blocks for organic field-effect transistors (OFETs) and organic photodetectors (OPDs) because they can potentially exhibit the best charge transport and photoelectric properties in organic materials. Nevertheless, it is usual for single-crystal OFETs to be built from one kind of organic material in which the dominant transport is either electron or hole; such OFETs show unipolar charge transport. Furthermore, single-crystal OPDs present high performance only in restricted regions because of the limited absorption of one-component single crystals. In an ideal situation, devices which comprise both electron- and hole-transporting single crystals with complementary absorptions, such as single-crystalline p-n heterojunctions (SCHJs), can permit broadband photoresponse and ambipolar charge transport. In this paper, a solution-processing crystallization strategy to prepare an SCHJ composed of C60 and 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-PEN) was shown. These SCHJs demonstrated ambipolar charge-transport characteristics in OFETs with a balanced performance of 2.9 cm2 V-1 s-1 for electron mobility and 2.7 cm2 V-1 s-1 for hole mobility. This demonstration is the first of single-crystal OFETs in which both electron and hole mobilities were over 2.5 cm2 V-1 s-1. OPDs fabricated upon as-prepared SCHJs exhibited highly sensitive photoconductive properties ranging from ultraviolet to visible and further to near-infrared regions as a result of complementary absorption between C60 and TIPS-PEN, thereby attaining photoresponsivities that are among the highest reported values within the OPDs. This work would provide valuable references for developing novel SCHJ systems to achieve significant progress in high-performance ambipolar OFETs and broadband OPDs.

Antisolvent-assisted controllable growth of fullerene single crystal microwires for organic field effect transistors and photodetectors.

There are only a few reported methods by which the size and morphology of organic single crystals for high-performance organic field-effect transistors (OFETs) or other devices can be controlled. Here, a facile solution-processed antisolvent vapor diffusion method was employed to grow millimeter-length C60 single crystal microwires directly in solution. The size of the microwires can be controllably varied via the C60 concentration and/or the choice of antisolvent. OFETs fabricated from the as-produced microwires exhibit mobilities as high as 2.30 cm2 V-1 s-1. A clear relationship between the crystal preparation conditions and device performance is revealed whereby it is observed that the lower the evaporation rate of antisolvent and/or the higher the C60 concentration, the higher the device performance. Photodetectors based on our microwires give a responsivity that is an order of magnitude higher than those grown by drop-casting methods. This study provides a facile method for the crystal engineering of size-tunable millimeter-length C60 single crystals, and revealed the important influences of the antisolvent on the C60 crystal size and the performance of devices based on them. We believe that our processing approach can be further exploited for a broad range of other organic semiconductors to achieve desirable single crystal size and morphology and thus obtain desirable OFETs and photodetector performance.

Effect of matrine against breast cancer by downregulating the vascular endothelial growth factor via the Wnt/ß-catenin pathway.

The aim of the present study was to investigate the effect of matrine on breast cancer and its underlying mechanism. Matrine is a major component of Sophora flavescens, exhibited antitumor activity in a number of neoplasms, including breast cancer. The present study revealed that matrine inhibited cell viability and induced apoptosis in 4T1 and MCF-7 cells in a dose- and time-dependent manner in vitro. In addition, matrine suppressed the 4T1-tumor growth, induced apoptosis, inhibited the expression of vascular endothelial growth factor and downregulated the Wnt/ß-catenin signaling pathway in vivo. All these findings indicated that matrine may be a novel effective candidate for the treatment of breast cancer.

Isomer-Pure Bis-PCBM-Assisted Crystal Engineering of Perovskite Solar Cells Showing Excellent Efficiency and Stability.

A fullerene derivative (α-bis-PCBM) is purified from an as-produced bis-phenyl-C61 -butyric acid methyl ester (bis-[60]PCBM) isomer mixture by preparative peak-recycling, high-performance liquid chromatography, and is employed as a templating agent for solution processing of metal halide perovskite films via an antisolvent method. The resulting α-bis-PCBM-containing perovskite solar cells achieve better stability, efficiency, and reproducibility when compared with analogous cells containing PCBM. α-bis-PCBM fills the vacancies and grain boundaries of the perovskite film, enhancing the crystallization of perovskites and addressing the issue of slow electron extraction. In addition, α-bis-PCBM resists the ingression of moisture and passivates voids or pinholes generated in the hole-transporting layer. As a result, a power conversion efficiency (PCE) of 20.8% is obtained, compared with 19.9% by PCBM, and is accompanied by excellent stability under heat and simulated sunlight. The PCE of unsealed devices dropped by less than 10% in ambient air (40% RH) after 44 d at 65 °C, and by 4% after 600 h under continuous full-sun illumination and maximum power point tracking, respectively.

Quantitative estimation of the replication kinetics of genotype 2 PRRSV strains with different levels of virulence in vitro.

Porcine reproductive and respiratory syndrome virus (PRRSV) has become an important pathogen for the swine industry, and has resulted in substantial economic losses. In 2006, highly pathogenic PRRSV (HP-PRRSV) belonging to genotype 2 was first identified in China. Here, the replication kinetics of genotype 2 PRRSV strains were estimated in vitro in MARC-145 cells and porcine alveolar macrophages (PAMs) using a TaqMan-based real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) assay. The lower limit of detection was 10 copies/µL, and the assay was linear between 10(1) and 10(8) copies/µL. The intra-assay coefficients of variation were 0.81-1.36%, and the inter-assay coefficients of variation were 1.77-2.56%. Compared to the low pathogenicity CH-1a-F45 strain, the viral loads of the highly pathogenic HuN4-F45 strain were 10(0.5)-10(1.05) and 10(0.84)-10(1.35) times greater in MARC-145 cells and PAMs, respectively from 12 to 96h after infection (P<0.01). This study is the first to demonstrate that the HuN4-F45 strain replicated at higher levels than CH-1a-F45 in MARC-145 cells and PAMs, suggesting that HuN4-F45 has more robust virus amplification efficiency than CH-1a-F45 in vitro.

Comparative analysis of apoptotic changes in peripheral immune organs and lungs following experimental infection of piglets with highly pathogenic and classical porcine reproductive and respiratory syndrome virus.

BACKGROUND: Our previous studies have demonstrated that piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) may develop significant thymus atrophy, which related to thymocytes apoptosis. However, apart from that detected in the thymus, there are no reports describing cell apoptosis induced by HP-PRRSV infection. In this study, we analyzed comparatively the pathological changes, cell apoptosis and viral load in peripheral immune organs including tonsil, inguinal lymph nodes (ILNs) and spleen and lungs following experimental infection of piglets with HP-PRRSV HuN4 and classical PRRSV CH-1a. FINDINGS: HP-PRRSV HuN4 exhibited much stronger cell tropism than CH-1a in immune organs and lungs of piglets. HuN4 infection led to the serious injuries in tonsils, ILNs, spleens and lungs, especially apoptosis in these organs was significant. CONCLUSIONS: HuN4 infection induced severe lesions (gross pathology, histopathology and cell apoptosis) in the peripheral immune organs and lungs of infected piglets. Large numbers of apoptotic cells in immune organs and lung induced by HuN4 may play a role in the pathogenesis of the HP-PRRS and the distinct injuries caused by HuN4 infection may be associated with the high mortality rate of HP-PRRS in pigs.

Characterization of thymus atrophy in piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus.

Our previous study has demonstrated that piglets infected with highly pathogenic PRRSV (HP-PRRSV) induced significant thymus atrophy. The aim of this study was to further investigate the lesions in thymus of piglets infected with HP-PRRSV or PRRSV and the changes of thymic T cell populations. The lesions were evaluated for the thymus/body weight ratios, pathological changes and virus load in thymus, apoptosis and ultrastructure of thymocytes. The result showed that thymus/body weight ratios of HP-PRRSV-infected piglets were significantly reduced compared to PRRSV-infected or control piglets, and thymic lesions were characterized by severe cortical depletion of thymocytes. The number of thymocytes undergoing apoptosis was increased approximately forty-fold in piglets infected with HP-PRRSV than that of PRRSV on 7 days post-inoculation (DPI). Double-positive thymocytes of piglets infected with HP-PRRSV were suppressed to a greater degree than either single positive subpopulation, but similar results were not observed in piglets infected with PRRSV. These results suggested that HP-PRRSV induced abundant apoptosis might result in severe thymus atrophy and the depletion of thymocytes.

Immune responses in piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus.

Porcine reproductive and respiratory syndrome virus (PRRSV) infection compromises the host's innate and adaptive immunity. The aim of this study was to investigate the immune responses of piglets infected with highly pathogenic (HP) PRRSV (HuN4 strain) with or without the immunization with CH-1R attenuated PRRSV vaccine. The response was evaluated for the clinical signs, pathological changes and virus load in immune organs, antibody responses and levels of serum IFN-γ, IL-4 and IL-10. The result showed that in comparison with the piglets received the immunization, the piglets infected with HP-PRRSV alone had the thymus atrophy, decreased serum levels of IL-4 and increased serum levels of IL-10 and INF-γ. These results suggest that elevated IL-10 levels at the early stage of the infection may enhance virus survival and delay the induction of protective immunity, while increased levels of IL-4 induce the effective immune responses and increase the animals' health status.

Secondary infection with Streptococcus suis serotype 7 increases the virulence of highly pathogenic porcine reproductive and respiratory syndrome virus in pigs.

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) and Streptococcus suis are common pathogens in pigs. In samples collected during the porcine high fever syndrome (PHFS) outbreak in many parts of China, PRRSV and S. suis serotype 7 (SS7) have always been isolated together. To determine whether PRRSV-SS7 coinfection was the cause of the PHFS outbreak, we evaluated the pathogenicity of PRRSV and/or SS7 in a pig model of single and mixed infection. RESULTS: Respiratory disease, diarrhea, and anorexia were observed in all infected pigs. Signs of central nervous system (CNS) disease were observed in the highly pathogenic PRRSV (HP-PRRSV)-infected pigs (4/12) and the coinfected pigs (8/10); however, the symptoms of the coinfected pigs were clearly more severe than those of the HP-PRRSV-infected pigs. The mortality rate was significantly higher in the coinfected pigs (8/10) than in the HP-PRRSV- (2/12) and SS7-infected pigs (0/10). The deceased pigs of the coinfected group had symptoms typical of PHFS, such as high fever, anorexia, and red coloration of the ears and the body. The isolation rates of HP-PRRSV and SS7 were higher and the lesion severity was greater in the coinfected pigs than in monoinfected pigs. CONCLUSION: HP-PRRSV infection increased susceptibility to SS7 infection, and coinfection of HP-PRRSV with SS7 significantly increased the pathogenicity of SS7 to pigs.

Dynamic changes in inflammatory cytokines in pigs infected with highly pathogenic porcine reproductive and respiratory syndrome virus.

Porcine reproductive and respiratory syndrome virus (PRRSV) infection induces both humoral and cellular immune responses. In this study, we investigated the changes in cytokine levels in peripheral blood between the highly pathogenic PRRSV HuN4 strain and its derivative strain HuN4-F112 obtained by serial propagation in MARC145 cells to 112 passages. The results demonstrated that pigs infected with HuN4 showed a loss of appetite, decrease in body weight, raised body temperature, and respiratory symptoms, along with interstitial pneumonia lesions. The PRRSV amounts in the pigs infected with HuN4 were 10(5) to 10(9) copies/ml in the blood and 10(10) to 10(11) copies/g in the lung tissues, whereas the virus amounts with HuN4-F112 were 10(2.15) to 10(3.13) copies/ml in the blood and 10(3.0) to 10(3.6) copies/g in the lungs. Moreover, the levels of interleukin 1 (IL-1), IL-6, tumor necrosis factor alpha (TNF-alpha), and alpha interferon (IFN-alpha) in peripheral blood were upregulated 7 days postinoculation with HuN4, which was earlier than in the HuN4-F112 group. Furthermore, cytokine levels in the pigs infected with HuN4 returned to normal on the 21st day postinoculation, while the levels in those infected with HuN4-F112 continued to increase. These results demonstrated that the pigs infected with the highly pathogenic PRRSV HuN4 strain generated earlier and higher levels of inflammatory cytokines, and the results also indicated that HuN4 may aggravate inflammation and damage tissues and organs. The low-pathogenic PRRSV HuN4-F112 strain induced lower levels of inflammatory cytokines, which may enhance the immune responses against the infection.