Over-expression of the CHS gene enhances resistance of Arabidopsis leaves to high light

Previous studies have suggested that high light (HL) stress causes photoinhibition in plants, while anthocyanins could protect the photosynthetic apparatus against photoinhibition. However, the photoprotection mechanism of anthocyanins is still ambiguous. We studied physiological responses and molecular changes for CHS-overexpression lines (CHS1, CHS2, CHS3), Arabidopsis thaliana ecotype Columbia (Col), and T-DNA insertion lines of CHS (tt4) under HL (200 μmol m−2 s−1) to explore the photoprotection mechanism of anthocyanins. The results showed that HL induced anthocyanin synthesis and accumulation. The leaves of CHS-overexpression lines turned reddest and the genes, including CHS, DFR, ANS, were expressed at highest levels. Thus, the CHS-overexpression lines maintained the highest photosynthetic capacity and suffered the least damage from HL of the three phenotypes. However, the CHS enzyme and anthocyanins were undetectable in tt4 during the experiment. Correspondingly, chlorophyll fluorescence parameters of tt4 declined greatly. The photosynthetic apparatus and cell membranes were also impaired dramatically. The physiological characteristics of Col were compared between CHS-overexpression lines and tt4. Together, the results suggest that over-expression of CHS gene enhances HL resistance by synthesizing more anthocyanins, that anthocyanins enhance the adaptability of plants to HL and that they maintain photosynthetic capacity via both antioxidation and attenuation of light.This work was funded by the National Key R&D Program of China (2017YFC1200105) and Guangdong Province Natural Science Foundation (2017A030313167, 2015A030311023). The study was also supported by the National Natural Science Foundation of China (31570398), Science and Technology Program of Guangzhou (20170701257) and Yang Cheng Scholar Program (10A040G)

Induction of immune responses in ducks with a DNA vaccine encoding duck plague virus glycoprotein C

<p>Abstract</p> <p>Background</p> <p>A DNA vaccine expressing glycoprotein C (gC) of duck plague virus (DPV) was evaluated for inducing immunity in ducks. The plasmid encoding gC of DPV was administered via intramuscular (IM) injection and gene gun bombardment.</p> <p>Results</p> <p>After immunization by both routes virus-specific serum antibody and T-cell responses developed. Vaccination of ducks by IM injection induced a stronger humoral, but weaker cell-mediated immune response. In contrast, a better cell-mediated immune response was achieved by using a gene gun to deliver DNA-coated gold beads to the epidermis with as little as 6 μg of DNA.</p> <p>Conclusions</p> <p>This demonstrated that both routes of DNA inoculation can be used for eliciting virus-specific immune responses. Although DNA vaccine containing DPV gC is effective in both intramuscular injection and gene gun bombardment, the latter could induce significantly higher cell-mediated responses against DPV.</p

4-(3-Carb­oxy­phen­yl)pyridinium nitrate

In the title salt, C12H10NO2 +·NO3 −, the dihedral angle between the pyridine ring and the benzene ring of the 4-(3-carb­oxy­phen­yl)pyridinium cation is 30.14 (2)°. Inversion-related pairs of cations are linked into dimers by pairs of O—H⋯O hydrogen bonds. Pairs of dimers are linked by N—H⋯O and C—H⋯O hydrogen bonds involving nitrate anions as acceptors, generating supra­molecular chains along the diagonal of the bc plane

Dual Energy Spectral CT Imaging for Colorectal Cancer Grading: A Preliminary Study

ObjectivesTo assess the diagnostic value of dual energy spectral CT imaging for colorectal cancer grading using the quantitative iodine density measurements in both arterial phase (AP) and venous phase (VP).Methods81 colorectal cancer patients were divided into two groups based on their pathological findings: a low grade group including well (n = 13) and moderately differentiated cancer (n = 24), and a high grade group including poorly differentiated (n = 42) and signet ring cell cancer (n = 2). Iodine density (ID) in the lesions was derived from the iodine-based material decomposition (MD) image and normalized to that in the psoas muscle to obtain normalized iodine density (NID). The difference in ID and NID between AP and VP was calculated.ResultsThe ID and NID values of the low grade cancer group were, 14.65±3.38mg/mL and 1.70±0.33 in AP, and 21.90±3.11mg/mL and 2.05± 0.32 in VP, respectively. The ID and NID values for the high grade cancer group were 20.63±3.72mg/mL and 2.95±0.72 in AP, and 26.27±3.10mg/mL and 3.51±1.12 in VP, respectively. There was significant difference for ID and NID between the low grade and high grade cancer groups in both AP and VP (all p<0.001). ROC analysis indicated that NID of 1.92 in AP provided 70.3% sensitivity and 97.7% specificity in differentiating low grade cancer from high grade cancer.ConclusionsThe quantitative measurement of iodine density in AP and VP can provide useful information to differentiate low grade colorectal cancer from high grade colorectal cancer with NID in AP providing the greatest diagnostic value

A Thymidine Kinase recombinant protein-based ELISA for detecting antibodies to Duck Plague Virus

<p>Abstract</p> <p>Background</p> <p>Duck plague virus (DPV) is the causative agent of Duck Plague (DP) that causes significant morbidity and mortality throughout duck-producing areas of the world. The diagnosis of DP currently relies on the use of live or inactivated whole DPV virion as antigens in ELISA, but it is too laborious and expensive for routine application, and it is still difficult to get purified DPV virion with current technology.</p> <p>Results</p> <p>In this study, we describe the expression and purification of a recombinant Thymidine Kinase (TK) protein which makes antigen in an in-house developed, optimized and standardized ELISA. The specificity of the optimized TK-ELISA was evaluated by antisera against Duck Plague Virus (DPV), Duck Hepatitis B Virus (DHBV), Duck Hepatitis Virus (DHV), <it>Riemerella Anatipestifer</it>(<it>R. A</it>), <it>Escherichia coli </it>(<it>E. coli</it>) and <it>Salmonella anatum </it>(<it>S. anatum</it>). Only antisera against DPV yielded a specific and strong signal. In order to determine the sensitivity of the TK-ELISA, a panel of diluted sera was tested, and the minimum detection limit of 1:2560 (OD450 nm = 0.401) was obtained according to the endpoint cut-off (0.2438). The repeatability and reproducibility under the experimental conditions demonstrates a low variability (P > 0.05). The suspected sera samples (n = 30) were determined by TK-ELISA and the positive rate is 90% (27/30), and the TK-ELISA showed 83.33% (22+3/30) coincidence rate with the Serum Neutralization Test (SNT) and 90% (24+3/30) coincidence rate with the whole DPV virion based-ELISA (DPV-ELISA). When defining the dynamics of antibody response to attenuated live DPV vaccine, the maximum antibodies is reached after 4 weeks.</p> <p>Conclusions</p> <p>The results suggest that the TK-ELISA provides high specificity, sensitivity, repeatability and reproducibility for detection of anti-DPV antibodies in duck sera, and has the potential to be much simpler than DPV-ELISA and SNT for the sera epidemiological investigation.</p

The anaphase promoting complex impacts repair choice by protecting ubiquitin signalling at DNA damage sites

Double-strand breaks (DSBs) are repaired through two major pathways, homology-directed recombination (HDR) and non-homologous end joining (NHEJ). While HDR can only occur in S/G2, NHEJ can happen in all cell cycle phases (except mitosis). How then is the repair choice made in S/G2 cells? Here we provide evidence demonstrating that APCCdh1 plays a critical role in choosing the repair pathways in S/G2 cells. Our results suggest that the default for all DSBs is to recruit 53BP1 and RIF1. BRCA1 is blocked from being recruited to broken ends because its recruitment signal, K63-linked poly-ubiquitin chains on histones, is actively destroyed by the deubiquitinating enzyme USP1. We show that the removal of USP1 depends on APCCdh1 and requires Chk1 activation known to be catalysed by ssDNA-RPA-ATR signalling at the ends designated for HDR, linking the status of end processing to RIF1 or BRCA1 recruitment.We thank S.-Y. Lin (MD Anderson Cancer Center) for cell lines; J. Rosen (Baylor College of Medicine) for reagents; H. Masai (Tokyo Metropolitan Institute of Medical Science) for U2OS-Fucci cell line; D. Durocher (University of Toronto) for HeLa-Fucci cell line; E. Citterio (Netherlands Cancer Institute) for GFP-USP3 construct; M.S.Y. Huen (The University of Hong Kong) for RNF168 antibody. This work was performed with facilities and instruments in the Imaging Core of National Center for Protein Science (Beijing), the Cytometry and Cell Sorting Core at Baylor College of Medicine with funding from the NIH (P30 AI036211, P30 CA125123 and S10 RR024574), the Integrated Microscopy Core at Baylor College of Medicine with funding from the NIH (HD007495, DK56338 and CA125123), and the John S. Dunn Gulf Coast Consortium for Chemical Genomics. We also thank other members of the Zhang lab for helpful discussion and support. This work was supported in part by an international collaboration grant (# 2013DFB30210) and a 973 Project grant (# 2013CB910300) from Chinese Minister of Science and Technology, in part by a Chinese National Natural Science Foundation grant (# 81171920), in part by a grant from The Committee of Science and Technology of Beijing Municipality, China (# Z141100000214015), and in part by NIH grants CA116097 and CA122623 to P.Z. J.J. is supported by grants from National Institutes of Health (R01GM102529) and the Welch Foundation (AU-1711). S.H. is supported by grants (# 81272488 and 81472795) from Chinese National Natural Science Foundation. Y.Z. is supported by grants from the National Natural Scientific Foundation of China (No. 81430055), Programs for Changjiang Scholars and Innovative Research Team in University (No. IRT_15R13).S

Unprecedented and highly stable lithium storage capacity of (001) faceted nanosheet-constructed hierarchically porous TiO2/rGO hybrid architecture for high-performance Li-ion batteries.

Active crystal facets can generate special properties for various applications. Herein, we report a (001) faceted nanosheet-constructed hierarchically porous TiO2/rGO hybrid architecture with unprecedented and highly stable lithium storage performance. Density functional theory calculations show that the (001) faceted TiO2 nanosheets enable enhanced reaction kinetics by reinforcing their contact with the electrolyte and shortening the path length of Li+ diffusion and insertion-extraction. The reduced graphene oxide (rGO) nanosheets in this TiO2/rGO hybrid largely improve charge transport, while the porous hierarchy at different length scales favors continuous electrolyte permeation and accommodates volume change. This hierarchically porous TiO2/rGO hybrid anode material demonstrates an excellent reversible capacity of 250 mAh g-1 at 1 C (1 C = 335 mA g-1) at a voltage window of 1.0-3.0 V. Even after 1000 cycles at 5 C and 500 cycles at 10 C, the anode retains exceptional and stable capacities of 176 and 160 mAh g-1, respectively. Moreover, the formed Li2Ti2O4 nanodots facilitate reversed Li+ insertion-extraction during the cycling process. The above results indicate the best performance of TiO2-based materials as anodes for lithium-ion batteries reported in the literature

Traditional Cantonese diet and nasopharyngeal carcinoma risk: a large-scale case-control study in Guangdong, China

<p>Abstract</p> <p>Background</p> <p>Nasopharyngeal carcinoma (NPC) is rare in most parts of the world but is a common malignancy in southern China, especially in Guangdong. Dietary habit is regarded as an important modifier of NPC risk in several endemic areas and may partially explain the geographic distribution of NPC incidence. In China, rapid economic development during the past few decades has changed the predominant lifestyle and dietary habits of the Chinese considerably, requiring a reassessment of diet and its potential influence on NPC risk in this NPC-endemic area.</p> <p>Methods</p> <p>To evaluate the association between dietary factors and NPC risk in Guangdong, China, a large-scale, hospital-based case-control study was conducted. 1387 eligible cases and 1459 frequency matched controls were recruited. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were estimated using a logistic regression model, adjusting for age, sex, education, dialect, and habitation household type.</p> <p>Results</p> <p>Observations made include the following: 1) consumption of canton-style salted fish, preserved vegetables and preserved/cured meat were significantly associated with increased risk of NPC, with enhanced odds ratios (OR) of 2.45 (95% CI: 2.03-2.94), 3.17(95% CI: 2.68-3.77) and 2.09 (95% CI: 1.22-3.60) respectively in the highest intake frequency stratum during childhood; 2) consumption of fresh fruit was associated with reduced risk with a dose-dependent relationship (p = 0.001); and 3) consumption of Canton-style herbal tea and herbal slow-cooked soup was associated with decreased risk, with ORs of 0.84 (95% CI: 0.68-1.03) and 0.58 (95% CI: 0.47-0.72) respectively in the highest intake frequency stratum. In multivariate analyses, these associations remained significant.</p> <p>Conclusions</p> <p>It can be inferred that previously established dietary risk factors in the Cantonese population are still stable and have contributed to the incidence of NPC.</p