Changing rapid weather variability increases influenza epidemic risk in a warming climate

It is believed that the continuing change in the Earth’s climate will affect the viral activity and transmission of influenza over the coming decades. However, a consensus of the severity of the risk of an influenza epidemic in a warming climate has not been reached. It was previously reported that the warmer winter can reduce influenza epidemic caused mortality, but this relation cannot explain the deadly influenza epidemic in many countries over northern mid-latitudes in the winter of 2017–2018, one of the warmest winters in recent decades. Here, we reveal that the widely spread 2017–2018 influenza epidemic can be attributed to the abnormally strong rapid weather variability. We demonstrate, from historical data, that the large rapid weather variability in autumn can precondition the deadly influenza epidemic in the subsequent months in highly populated northern mid-latitudes; and the influenza epidemic season of 2017–2018 was a typical case. We further show that climate model projections reach a consensus that the rapid weather variability in autumn will continue to strengthen in some regions of northern mid-latitudes in a warming climate, implying that the risk of an influenza epidemic may increase 20% to 50% in some highly populated regions in the later 21st century

FC-98 Regulates TLR9-Mediated of CXCL-10 Expression in Dendritic Cells via MAPK and STAT1 Signaling Pathway

Dendritic cells (DCs), as the most potent professional antigen presenting cells, play a crucial role in both innate and adaptive immune systems. Genomic bacterial DNA mimicked by unmethylated CpG motifs is discovered to possess immunostimulatory effects. CpG-DNA recognized by Toll-like receptor 9 (TLR9) on DCs arouses many immune diseases (such as cancer, viral infection, and autoimmune disorders). In this study we investigated the effects of FC-98 on CpG-induced bone marrow-derived DCs (BMDCs). The results showed that FC-98 significantly inhibited the CpG-induced BMDCs maturation and function by suppressing the expression of surface markers (CD40, CD80, CD86, and MHCII). Moreover, FC-98 downregulated the expression of C-X-C motif chemokine 10 (CXCL-10) both at the mRNA and protein level after CpG induction. Meanwhile, FC-98 markedly affected the migration of BMDCs to T cells without affecting their endocytosis capacity. Furthermore, FC-98 was confirmed to decrease CXCL-10 expression by inhibiting CpG-induced activation of MAPKs (ERK, JNK, and p38) and STAT1 signaling. Overall, these results suggested that FC-98 was a potential molecule in the treatment of CXCL-10-mediated immune diseases

Apigenin inhibits enterovirus-71 infection by disrupting viral RNA association with trans-acting factors.

Flavonoids are widely distributed natural products with broad biological activities. Apigenin is a dietary flavonoid that has recently been demonstrated to interact with heterogeneous nuclear ribonucleoproteins (hnRNPs) and interferes with their RNA editing activity. We investigated whether apigenin possessed antiviral activity against enterovirus-71 (EV71) infection since EV71 infection requires of hnRNP proteins. We found that apigenin selectively blocks EV71 infection by disrupting viral RNA association with hnRNP A1 and A2 proteins. The estimated EC50 value for apigenin to block EV71 infection was determined at 10.3 µM, while the CC50 was estimated at 79.0 µM. The anti-EV71 activity was selective since no activity was detected against several DNA and RNA viruses. Although flavonoids in general share similar structural features, apigenin and kaempferol were among tested compounds with significant activity against EV71 infection. hnRNP proteins function as trans-acting factors regulating EV71 translation. We found that apigenin treatment did not affect EV71-induced nucleocytoplasmic redistribution of hnRNP A1 and A2 proteins. Instead, it prevented EV71 RNA association with hnRNP A1 and A2 proteins. Accordingly, suppression of hnRNP A1 and A2 expression markedly reduced EV71 infection. As a positive sense, single strand RNA virus, EV71 has a type I internal ribosome entry site (IRES) that cooperates with host factors and regulates EV71 translation. The effect of apigenin on EV71 infection was further demonstrated using a bicistronic vector that has the expression of a GFP protein under the control of EV71 5'-UTR. We found that apigenin treatment selectively suppressed the expression of GFP, but not a control gene. In addition to identification of apigenin as an antiviral agent against EV71 infection, this study also exemplifies the significance in antiviral agent discovery by targeting host factors essential for viral replication

Novel CSF biomarkers for diagnosis and integrated analysis of neuropsychiatric systemic lupus erythematosus: based on antibody profiling

Abstract Background Neuropsychiatric systemic lupus erythematosus (NPSLE), with various morbidities and multiple manifestations in the central nervous system, remains a limited standard for diagnosis. Our study was to discover novel biomarkers for improving the diagnostic efficiency for NPSLE. Methods We performed a quantitative planar protein antibody microarray to screen 1000 proteins in cerebrospinal fluid from controls, systemic lupus erythematosus (SLE, non-NPSLE) patients, and NPSLE patients. Differentially expressed proteins (DEPs) as candidate biomarkers were developed into a custom multiplexed protein antibody array for further validation in an independent larger cohort. Subsequently, we used least absolute shrinkage and selection operator regression (LASSO) analysis and multivariable logistic regression analysis for optimizing feature selection and constructing a diagnostic model. A receiver operating characteristic curve (ROC) was generated to assess the effectiveness of the models. Results The expression of 29 proteins in CSF was significantly altered in the comparison of the three groups. We selected 17 proteins as candidate biomarkers in accordance with protein interaction analysis. In the larger cohort, we identified 5 DEPs as biomarkers for NPSLE, including TCN2, CST6, KLK5, L-selectin, and Trappin-2. The diagnostic model included 3 hub proteins (CST6, TCN2, KLK5) and was best at discriminating NPSLE from SLE patients. These CSF biomarkers were also highly associated with disease activity. In addition, there were 6 molecules with remarkable changes in NPSLE CSF and hippocampus, which indicated the consistency of the environment in the brain and the promising molecular targets in the pathogenesis of NPSLE. Conclusions The dual-chips screening strategy demonstrated KLK5, L-selectin, Trappin-2, TCN2, and CST6 as CSF biomarkers for diagnosing NPSLE

Apigenin treatment does not affect hnRNP A1 or hnRNP A2 nucleocytoplasmic redistribution induced by EV71 infection. (A, B) Immunostaining study to determine hnRNP A1 and hnRNP A2 redistribution.

<p>RD cells on coverslips were untreated or treated with 30 µM apigenin 2 hr prior to EV71 infection. The cells were infected with EV71 for 6 hr at an MOI of 40. The cells were then fixed and stained with rabbit anti-hnRNP A1 (A, red) or anti-hnRNP A2 (B, red), followed by Alexa Fluor 568-conjugated anti-rabbit antibody. EV71 VP1 protein expression was stained with a mouse anti-EV71 antibody (green) and the corresponding secondary antibody. The nuclei were visualized by staining with DAPI (blue). The merged images represent the areas within the yellow squares and highlight the relative location of hnRNP to the nuclei. (A) EV71 infection causes hnRNP A1 redistribution, while apigenin treatment does not affect hnRNP A1 redistribution. (B) EV71 infection causes hnRNP A2 redistribution and apigenin treatment does not affect hnRNP A2 redistribution. Images were collected with 400x magnifications and were processed using Image J. <b>(C, D) hnRNP A1 and A2 redistribution by fractionation studies.</b> Apigenin treated or control RD cells were uninfected or infected with EV71 at an MOI of 40 for 6 hr. The cells were harvested and fractionated for detection of cytosolic and nuclear proteins by immunoblotting. (C) redistribution of hnRNP A1 protein and (D) redistribution of hnRNP A2 protein. Lamin B and GAPDH were used as loading controls for nuclear and cytoplasmic proteins, respectively. Results are representatives of two independent experiments.</p

Antiviral activity evaluation of flavonoids against EV71 infection. (A) Names and chemical structures of flavonoids tested in this study.

<p>The compounds were evaluated for their antiviral activity against EV71 infection. Apigenin and kaempferol were the only compounds that showed antiviral activity at 30 µM concentration. <b>(B, C) Confirmation of kaempferol antiviral activity by titration for infectious virion production (B) and viral VP1 protein expression (C).</b> RD cells were untreated or pretreated with kaempferol along with apigenin, naringenin and hesperetin at 30 µM for 2 hr and then infected with EV71 (MOI = 0.10) for 36 hr. Infectious virion production was titrated using a secondary infection assay (B) and VP1 expression was detected by immunoblotting (C). Que: quercetin; Api: apigenin; Kae: kaempferol; Hes: hesperetin; Nar: naringenin. GAPDH expression was used as a loading control. Both studies were performed twice independently. Data are presented as mean ± SD of triplicate samples. An unpaired <i>t</i> test was performed for statistical analysis. *: <i>p</i>≤0.05. <b>(D) Anti-oxidative agent </b><b><i>N</i></b><b>-acetyl cysteine (NAC) treatment does not affect EV71 infection.</b> RD cells were untreated or pretreated with NAC at varying concentrations (1, 3, and 10 mM) or apigenin at 30 µM for 2 hr. The cells were then infected with EV71 (MOI = 0.10 TCID₅₀ per cell) for 36 hr. EV71 VP1 protein expression were determined by immunoblotting analysis. The experiment was performed twice independently. GAPDH was used as a loading control.</p

Inhibition of EV71 infection by apigenin. (A) Determination of CC₅₀ of apigenin.

<p>RD cells in 96 well plates were treated with apigenin at indicated concentrations. Cell viability was assayed at 72 hr post-treatment by measuring MTT reduction. OD readings of duplicate samples were plotted and used to extrapolate CC₅₀ values using GraphPad Prism. The experiment was performed two times independently. Data are presented as mean ± standard deviation (SD) of duplicate samples. <b>(B) Evaluation of apigenin antiviral activity by measuring cytopathic effect.</b> The permissive RD cells were pretreated 2 hr prior to EV71 infection with apigenin at 3, 10, and 30 µM or mock-treated with DMSO. Ribavirin was included as a positive control. Two MOIs (0.03 and 0.10 TCID₅₀ per cell, respectively) were used to infect the cells. The cytopathic effect due to EV71 infection was quantified by measuring cell viability with an MTT assay. The ratios of OD readings of infected samples over uninfected controls were used for this plot. The experiment was performed three times independently. The experiment was performed three times independently and data are presented as mean ± SD of duplicate samples. An unpaired <i>t</i> test was performed for statistical analysis. *: <i>p</i>≤0.05; **: <i>p</i>≤0.01; ***: <i>p</i>≤0.001. <b>(C, D) Validation of apigenin antiviral effect against EV71 infection by titration and immunoblotting for viral VP1 expression.</b> RD cells were pretreated with apigenin at 3, 10 or 30 µM or remained untreated. The cells were then infected with EV71 at MOI of 0.03 or 0.10 TCID₅₀ per cell for 36 hr. Production of infectious virion production (C) or EV71 VP1 protein expression (D) were determined as described in experimental procedures. Titration data are presented as mean ± SD of triplicate samples. The experiment was performed two times independently. An unpaired <i>t</i> test was performed for statistical analysis. *: <i>p</i>≤0.05; **: <i>p</i>≤0.01. GAPDH expression was used as a loading control. <b>(E) Determination of EC₅₀ of apigenin anti-EV71 activity.</b> RD cells in 96-well plates were treated with apigenin at varying concentrations or remained untreated. The cells were then infected with EV71 at an MOI of 0.01 TCID₅₀ per cell for 72 hr. Cell viability was used as a measurement for antiviral effect. Ratios of OD readings of infected over uninfected controls were used for this plot. EC₅₀ value was extrapolated using GraphPad Prism. The experiment was performed two times independently. Data are presented as mean ± SD of triplicate samples. <b>(F) Time of drug-addition antiviral effect of apigenin.</b> Monolayers of RD cells were pretreated (-2 hr) or treated with 30 µM apigenin at times as indicated. The cells were infected with EV71 at an MOI of 0.01 TCID₅₀ per cell for 72 hr. Cell viability was measured using a MTT method. OD reading of triplicate samples at -2 hr of apigenin addition was used as a reference for 100% inhibition, and readings at other times were used to obtain relative inhibition rates at indicated times. The results are representative of two independent experiments. Data are presented as mean ± SD of duplicate samples. <b>(G) Assay of apigenin antiviral effect against herpes simplex viruses (HSV) and coxsackievirus A16 (CAV16).</b> Vero cells in triplicate were pretreated with apigenin at 30 µM and then infected with EV71, CAV16, HSV-1 or HSV-2 at an appropriate MOI for each virus for 48 hr. Cell viability was quantitatively measured by MTT assay. The percentages of viable cells were expressed using the ratio of OD readings of infected (solid bar) or infected and treated (hatched bar) samples <i>vs</i> uninfected and drug-treated controls. The experiments were performed twice independently. Data are presented as mean ± SD of duplicate samples. An unpaired <i>t</i> test was performed for statistical analysis. *: <i>p</i>≤0.05.</p

An Epigenetic Compound Library Screen Identifies BET Inhibitors That Promote HSV-1 and -2 Replication by Bridging P-TEFb to Viral Gene Promoters through BRD4

<div><p>The human HSV-1 and -2 are common pathogens of human diseases. Both host and viral factors are involved in HSV lytic infection, although detailed mechanisms remain elusive. By screening a chemical library of epigenetic regulation, we identified bromodomain-containing protein 4 (BRD4) as a critical player in HSV infection. We show that treatment with pan BD domain inhibitor enhanced both HSV infection. Using JQ1 as a probe, we found that JQ1, a defined BD1 inhibitor, acts through BRD4 protein since knockdown of BRD4 expression ablated JQ1 effect on HSV infection. BRD4 regulates HSV replication through complex formation involving CDK9 and RNAP II; whereas, JQ1 promotes HSV-1 infection by allocating the complex to HSV gene promoters. Therefore, suppression of BRD4 expression or inhibition of CDK9 activity impeded HSV infection. Our data support a model that JQ1 enhances HSV infection by switching BRD4 to transcription regulation of viral gene expression from chromatin targeting since transient expression of BRD4 BD1 or BD1/2 domain had similar effect to that by JQ1 treatment. In addition to the identification that BRD4 is a modulator for JQ1 action on HSV infection, this study demonstrates BRD4 has an essential role in HSV infection.</p></div

Apigenin disrupts EV71 RNA association with hnRNP A1 and A2 proteins. (A) Diagram of the 5′-UTR region of EV71 genome.

<p>The 5′-UTR region of EV71 strain used in this study was sequenced and used for the prediction of secondary structure using MFOLD program and presented using ChemBioDraw. The numbers indicate relative position of nucleotides. Primers 1 to 3 indicate positions of corresponding oligos used for genome detection by RT-PCR. <b>(B) Schematic drawing of experimental procedures of cross-link followed by immunoprecipitation and RT-PCR amplification for hnRNP-associated viral RNA.</b><b>Detection of EV71 RNA association with hnRNP A1 (C) and hnRNP A2 (D) proteins.</b> RD cells were pretreated with 30 µM apigenin or untreated. The cells were then infected with EV71 at an MOI = 40 for 6 hr. hnRNP-associated viral RNA was detected using RIP followed by RT-PCR. Anti-FLAG antibody was used as a control for immunoprecipitation. In those experiments, portions of the cell lysates were used to determine total RNA input by RT-PCR. Two sets of oligos (nt 97–745 and 167–745, respectively) were used for the detection of hnRNP-associated EV71 RNA. Data are representative of three independent experiments. <b>(E) Suppression of apigenin on IRES activity.</b> A bicistronic reporter gene system (diagram) was constructed for testing EV71 IRES activity. The plasmid, named pEV-ZsGreen1, was transfected to RD cells, using pRL as an internal control for firefly luciferase expression (refer to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110429#s2" target="_blank">materials and methods</a>). The expression of ZsGreen GFP was quantitatively measured by FACS analysis (middle panel). The expression of firefly luciferase and Renila luciferase was determined using Dual-Glo reagent. The percentages of GFP positive cells in apigenin-treated or control samples were plotted against luciferase activity (lower panel, arbitrary number using untreated pEV-ZsGreen1 as 1). The experiment was performed two times independently. <b>(F) Screening of siRNAs that suppress hnRNP A1 or hnRNP A2 expression.</b> RD cells in 24-well plates were transfected with a scrambled siRNA (NC, at 50 pmol/well) or an siRNA (50 pmol/well) targeting hnRNP A1 (named as A1#1 to 3) or hnRNP A2 (named as A2#1 to 3) expression. The sequences for those oligos are given in experimental procedures. The cells were harvested at 60 hr post transfection and protein expression was detected by immunoblotting. GAPDH expression was used as a control. A1#1 and A2#3 were selected and used for knockdown hnRNP A1 and hnRNP A2 studies. Results are representatives of three independent experiments. <b>(G) Suppression of hnRNP A1 and A2 expression by siRNA inhibits EV71 infection.</b> RD cells in a 24-well plate were transfected with a scrambled control siRNA (NC, 70 pmol/well), siRNA for suppression of hnRNP A1 (A1#1, 35 pmol A1#1 plus 35 pmol NC siRNA), hnRNP A2 (A2#3, 35 pmol A2#3 plus 35 pmol NC siRNA), or 35 pmol each of A1#1 and A2#3 (A1+A2) for combined suppression of hnRNP A1 and A2 expression. The cells were fed with fresh medium at 60 hr post transfection and then infected with EV71 (MOI = 0.10) for another 36 hr. Protein expression was detected by immunoblotting. In parallel experiments, the samples were harvested and infectious virion production was determined by titration. Results are representatives of two independent experiments. Data are presented as mean ± SD of triplicate samples. An unpaired <i>t</i> test was performed for statistical analysis. *: <i>p</i>≤0.05.</p

污水生物处理实际工艺中氧化亚氮的释放:现状与挑战

The pathways for nitrous oxide (NO) production from biological nitrogen removal processes in wastewater treatment plants (WWTPs) are illustrated. Comparative analyses of NO emissions from some typical wastewater treatment processes are conducted and the mechanisms for their discrepancy are discussed in detail. The methods for reduction of NO emission are proposed. According to the recommended NO emissions factors, the gross quantity of NO emissions from WWTPs in China is estimated to be 1.26×10g in 2011. Further study on NO emissions from biological wastewater treatment processes is recommended