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The functions of ubiquitin‐conjugating enzymes (E2) in plant immunity are not well understood. In this study, OsUBC26, a rice ubiquitin‐conjugating enzyme, was characterized in the defence against Magnaporthe oryzae. The expression of OsUBC26 was induced by M. oryzae inoculation and methyl jasmonate treatment. Both RNA interference lines and CRISPR/Cas9 null mutants of OsUBC26 reduced rice resistance to M. oryzae. WRKY45 was down‐regulated in OsUBC26 null mutants. In vitro E2 activity assay indicated that OsUBC26 is an active ubiquitin‐conjugating enzyme. Yeast two‐hybrid assays using OsUBC26 as bait identified the RING‐type E3 ligase UCIP2 as an interacting protein. Coimmunoprecipitation assays confirmed the interaction between OsUBC26 and UCIP2. The CRISPR/Cas9 mutants of UCIP2 also showed compromised resistance to M. oryzae. Yeast two‐hybrid screening using UCIP2 as bait revealed that APIP6 is a binding partner of UCIP2. Moreover, OsUBC26 working with APIP6 ubiquitinateds AvrPiz‐t, an avirulence effector of M. oryzae, and OsUBC26 null mutation impaired the proteasome degradation of AvrPiz‐t in rice cells. In summary, OsUBC26 plays important roles in rice disease resistance by regulating WRKY45 expression and working with E3 ligases such as APIP6 to counteract the effector protein AvrPiz‐t from M. oryzae. [ABSTRACT FROM AUTHOR]

This paper presents a new preparation method for aromatics through the catalytic pyrolysis of furfural from biomass. The use of HZSM‐5 zeolite as a catalyst with different pore sizes, pore geometries, and acidity levels was investigated for the conversion of furfural into aromatics. Results showed that product selectivity was dependent on the pore size and radius of the zeolites. Catalyst and reaction conditions were critical in maximizing the selectivity of aromatic hydrocarbons. The highest yield of 58.49 wt% was achieved at 10 ml min−1 N2 purge rate, 0.5 ml h−1 feeding rate, 500 °C pyrolysis temperature, and 23 catalyst Si/Al ratio. The highest carbon yield of benzene (12.74 %), toluene (11.13 %), xylene (8.54 %), and total (30.85 %) was obtained when the HZSM‐5 zeolite was treated with HCl (0.9 mol/L) solution. On the basis of current experimental results and previous reports, the mechanism of Lewis and Bronsted acid sites was inferred. [ABSTRACT FROM AUTHOR]

Using the DNA origami technique, we constructed a DNA nanodevice functionalized with small interfering RNA (siRNA) within its inner cavity and the chemotherapeutic drug doxorubicin (DOX), intercalated in the DNA duplexes. The incorporation of disulfide bonds allows the triggered mechanical opening and release of siRNA in response to intracellular glutathione (GSH) in tumors to knockdown genes key to cancer progression. Combining RNA interference and chemotherapy, the nanodevice induced potent cytotoxicity and tumor growth inhibition, without observable systematic toxicity. Given its autonomous behavior, exceptional designability, potent antitumor activity and marked biocompatibility, this DNA nanodevice represents a promising strategy for precise drug design for cancer therapy. [ABSTRACT FROM AUTHOR]

Measuring the nitrogen isotope compositions (δ15N) of nitric oxide (NO) from different sources helps to quantify the relative contributions of atmospheric NOx. Soil is one of the most important sources of atmospheric NOx, but only limited measurements on the δ15N of soil‐emitted NO exist, hampering our ability to partition sources to air pollution. Here we conducted soil incubations to measure the δ15N‐NO under defined aerobic or anaerobic conditions, favoring either nitrification or denitrification. Soils were collected from seven sites spanning three ecosystems in northern China (two agricultural, two forest, and three grassland sites). We found that the δ15N‐NO and their associated N isotope fractionations were significantly different between anaerobic and aerobic conditions in seven soils. Under aerobic condition, the δ15N‐NO ranged from −62‰ to −50‰ (averaged −56 ± 4‰), being significantly more negative (by 23‰) than those under anaerobic condition (−45‰ to −23‰, averaged −33 ± 7‰). The apparent N isotope fractionation for NO production under aerobic condition (15εaerobic = 61 ± 3‰) was significantly higher (by 26‰) than under anaerobic condition (15εanaerobic = 35 ± 6‰), with a small variability among ecosystem types. Our study demonstrates that the δ15N‐NO from different soils are very different from fuel combustions (mainly from 0‰ to +20‰), supporting that measuring 15N is a useful tool to partition the contributions of soil NO to atmospheric NOx. Our results also imply δ15N‐NO produced by nitrification and denitrification distinctly different, as these two processes are dominant processes producing NO under aerobic and anaerobic conditions, respectively. Plain Language Summary: Nitric oxide (NO) affects the atmosphere chemistry and NO itself a key component of air pollution and a precursor to other air pollutants like particulate matter and ozone. To reduce the air pollution, it is crucial to identify the atmospheric NO sources. Measuring 15N natural abundance has been considered as a promising tool to identify different sources, but the measurement on δ15N for soil‐emitted NO is limited, adding to the large uncertainties on NO partitioning. Here we measured the δ15N‐NO emitted from three ecosystem types across seven sites (two agriculture, two forest, and three grassland sites) under defined anaerobic or aerobic conditions. We found that soil‐emitted NO was 15N‐depleted (−62‰ to −23‰) related to the source from fossil fuel combustion (0–20‰), suggesting that δ15N can be used to separate these two sources. We also found that the δ15N‐NO under aerobic condition (nitrification prevailing, −62‰ to −50‰) was much lower than under anaerobic condition (denitrification prevailing, −45‰ to −23‰), which provide a useful tool to better understand the relative contributions of different sources of NO. In sum, soil‐emitted NO has their own different isotope fingerprint, depending on the soil oxygen conditions, and can be used to partition sources. Key Points: The δ15N‐NO from soil (−62‰ to −23‰) is different from fuel combustion (0‰ to 20‰), allowing effective source partitionThe δ15N‐NO produced under aerobic condition (favor nitrification) was more negative than under anaerobic condition (favor denitrification)The 15ε for NO production under aerobic condition (61 ± 3‰) was significantly higher than under anaerobic condition (35 ± 6‰) [ABSTRACT FROM AUTHOR]

Nitrogen stable isotope composition (δ15N) of nitrate (NO3−) deposition can aid in source apportionment of its precursor emissions, nitrogen oxides (NOx), with implications in mitigation policy to address serious air pollution. However, potential δ15N fractionation during atmospheric NO3− formation may hinder accurate quantification of NOx contributions. Previously, NOx photochemical reactions have been suggested to be the dominant δ15N fractionation process in NO3− formation. Here, we have quantified the potential fractionation effects associated with NOx photochemical reactions based upon δ15N‐NO3− measured in 1 year of daily‐based bulk deposition samples in Shenyang, a megacity with distinct seasonal fossil fuel combustion in northeastern China. The mean δ15N was 0.9 ± 4.0‰ and ranged from −4.9 to 8.3‰, with the lowest and highest values observed during summer and winter, respectively. Calculated NOx photochemical equilibrium fractionation may account for up to 42% of the observed seasonal δ15N change in NO3− deposition. However, the relative NOx source contribution trends, estimated based upon a δ15N Bayesian mixing model, were insensitive to NOx photochemical fractionation considerations. Overall, NOx source partitioning based upon averaged year‐long δ15N of bulk NO3− deposition estimated the following relative trend in NOx emission sources: coal combustion > biomass burning = vehicle emissions ≫ soil emissions. Seasonally, the increase of coal combustion emissions from summer to winter drives the seasonality of δ15N in NO3− deposition, indicating a necessity to control NOx emissions from coal combustion to improve wintertime air quality. Key Points: The δ15N‐NO3− measured in bulk deposition of a Chinese megacity shows mean values high in winter (5.7‰) and low in summer (−2.7‰)The seasonality of δ15N was largely explained by source change rather than isotopic fractionation driven by NOx photochemical equilibriumCoal combustion is the dominant source driving the δ15N seasonality of NO3− deposition in Shenyang, China [ABSTRACT FROM AUTHOR]

Background: No data are available on the prevalence of mortality in neonates after major surgery such as laparotomy in China. Methods: In a tertiary general hospital, 142 newborns who underwent laparotomy for a variety of surgical conditions in the past 6 years were included in this study in Beijing, China. Pre‐, intra‐, and postoperative variables potentially predictive of postoperative 30 day mortality were collected and compared between the surviving and deceased newborns. Results: Death ≤30 days after laparotomy occurred in 19 of 142 newborns (13.4%) during the study period. Newborns diagnosed with necrotizing enterocolitis (NEC) had the worst outcome (OR, 11.4). Significantly more neonates in the 30 day death group were intubated preoperatively (52.6%) compared with the survival group (19.5%; OR, 10.0). Base excess ≤−10 mmol/L immediately after laparotomy was associated with negative prognosis in the early postoperative period (OR, 11.2). Conclusion: The mortality rate of newborns ≤30 days after laparotomy was 13.4% in a Chinese tertiary general hospital in the past 6 years. The factors associated with early death were NEC, preoperative intubation with mechanical ventilation, and postoperative immediate base excess ≤−10 mmol/L. [ABSTRACT FROM AUTHOR]

Summary: Valsa mali is the causal agent of apple Valsa canker, a destructive disease in East Asia. Effector proteins play important roles in the virulence of phytopathogenic fungi, and we identified five Hce2 domain‐containing effectors (VmHEP1, VmHEP2, VmHEP3, VmHEP4 and VmHEP5) from the V.mali genome. Amongst these, VmHEP1 and VmHEP2 were found to be up‐regulated during the early infection stage and VmHEP1 was also identified as a cell death inducer through its transient expression in Nicotiana benthamiana. Although the deletion of each single VmHEP gene did not lead to a reduction in virulence, the double‐deletion of VmHEP1 and VmHEP2 notably attenuated V. mali virulence in both apple twigs and leaves. An evolutionary analysis revealed that VmHEP1 and VmHEP2 are two paralogues, under purifying selection. VmHEP1 and VmHEP2 are located next to each other on chromosome 11 as tandem genes with only a 604 bp physical distance. Interestingly, the deletion of VmHEP1 promoted the expression of VmHEP2 and, vice versa, the deletion of VmHEP2 promoted the expression of VmHEP1. The present results provide insights into the functions of Hce2 domain‐containing effectors acting as virulence factors of V. mali, and provide a new perspective regarding the contribution of tandem genes to the virulence of phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

Multidrug resistance (MDR) is a major obstacle in the clinical treatment of cancer. Herein, a facile strategy is reported to construct a versatile DNA nanostructure as a co‐delivery vector of RNA interference (RNAi) and chemodrugs to combat multidrug‐resistant tumor (MCF‐7R) in vitro and in vivo. In the tailored nanocarrier, two linear small hairpin RNA (shRNA) transcription templates targeting MDR‐associated genes (gene of P‐glycoprotein, a typical drug efflux pump; and gene of survivin, a representative anti‐apoptotic protein) are precisely organized in the chemodrug (doxorubicin, DOX) pre‐loaded DNA origami. With the incorporation of active targeting and controlled‐release elements, these multifunctional DNA nanocarriers can successfully enter the target MCF‐7R cells and synergistically inhibit tumor growth without apparent systemic toxicity. This tailored DNA nanoplatform, which combines RNAi therapy and chemotherapy, provides a new strategy for the treatment of multidrug‐resistant tumors. A DNA nanoplatform‐based co‐delivery system containing two linear shRNA transcription templates against tumor‐associated genes (Pgp and survive) and a chemotherapeutic drug (doxorubicin, DOX) was constructed for synergistic therapy of multidrug resistant (MDR) tumors in vivo. [ABSTRACT FROM AUTHOR]

Objective: The purpose of the present study was to evaluate the clinical features of patients with radioiodine refractory (RAIR) differentiated thyroid carcinoma (DTC) and establish an effective risk score for postoperative radioiodine refractoriness. Subjects and methods: Data were retrospectively collected from 5163 patients admitted to our center after thyroid surgery. Radioiodine refractoriness was defined according to criteria used in the 2015 American Thyroid Association guidelines. The scoring system was established by independent risk factors identified by univariate and multivariate analyses. The optimal index points for predicting the prevalence of radioiodine refractoriness and the model discriminatory power were assessed by receiver operating characteristic (ROC) curves. Results: One hundred and twelve (2.2%) patients developed RAIR DTC. Smoking, tumor type (follicular thyroid cancer), extrathyroid extension, lymph node metastasis number (≥4), lymph node metastasis rate (≥53%), and pN stage (N1) were highly positively correlated with the prevalence of RAIR DTC. The cutoff value of seven points was found to be the best for predicting the prevalence of RAIR DTC, and the scoring system presented better discrimination than other single independent predictors. Conclusions: Based on our multivariable prediction model, patients with ≥7 index points may need to undergo more active surveillance or aggressive treatment due to the high risk of RAIR DTC. The radioiodine refractory differentiated thyroid carcinoma is associated with adverse prognosis and responsible for a large number of deaths. A multivariable prediction model was established, aiming to identify the potential patients, to optimize their management in the early stage. [ABSTRACT FROM AUTHOR]

DNA has been demonstrated to be a promising engineering material for the fabrication of pre-designed nanostructures and nanodevices, which feature structural programmability, spatial addressability, dynamic mechanics, and biocompatibility. Here, we review the recent progress in the design, construction and biomedical applications of DNA nanostructures, particularly imaging probes and drug delivery carriers. We discuss several key points for in vivo biomedical applications of DNA-based delivery systems, such as the cost and safety issues. In the end, we explore the challenges and opportunities of DNA nanotechnology in the field of nanomedicine. [ABSTRACT FROM AUTHOR]

ABSTRACT Polymeric hybrid nanoparticles were synthesized via surface-initiated atom-transfer radical polymerization (SI-ATRP) method on the surface of gold nanoparticles in cyclohexanone. Tetraoctyl ammonium bromide (TOAB) as a phase transfer agent was used to transfer the gold nanoparticles into cyclohexanone, which will be replaced by disulfide initiator on the surface of gold nanoparticles. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-vis spectroscopy were utilized to characterize the product to make sure the experiment had been conducted. The results showed that the polymeric gold hybrid nanoparticles with different structures could be controlled by adjusting the ratio of initiator and gold nanoparticles in ATRP. If the ratio is very little, asymmetric polystyrene-gold hybrid nanoparticles were synthesized, and a single gold nanoparticle was attached with a polystyrene sphere. If the ratio becomes larger, core-shell polystyrene-gold nanocomposite particles were obtained resulting in gold nanoparticle encapsulated by a uniform polymer shell. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43584. [ABSTRACT FROM AUTHOR]