Identification, characterization and prevalence in southern China of a new iflavirus in the leafhopper Recilia dorsalis (Hemiptera: Cicadellidae).

The leafhopper Recilia dorsalis (Hemiptera: Cicadellidae) is not only a significant pest in agriculture but also an important vector involved in transmitting numerous pathogens that are known to cause economic losses by affecting rice crops. Here, a new iflavirus was discovered in the leafhopper R. dorsalis by employing a transcriptomic approach. The complete viral genome was determined to be 10,711 nucleotides (nt) in length and contains a single open reading frame (ORF) encoding a putative polyprotein comprised of 3,161 amino acids (aa), which is flanked by 5' and 3' untranslated regions. The full viral genome nt and the deduced polyprotein aa sequence showed the highest similarity (71.6% and 77.8%, respectively) with Langfang leafhopper iflavirus. Phylogenetic analysis based on the RdRp domain indicated that the isolated virus, which we have tentatively named Recilia dorsalis iflavirus 2 (RdIV2), is clustered with the members of the family Iflaviridae. Moreover, the results of our surveys indicate that RdIV2 predominates in southwestern Guangdong and southeastern Guangxi, China, and was absent in the other three species of leafhoppers; Nephotettix cincticeps, N. virescens and N. nigropictus. Notably, R. dorsalis was found to be co-infected with RdIV2 and rice stripe mosaic virus (RSMV; a well-known rice-infecting virus vectored by R. dorsalis) in rice fields, although the co-infection rate is low.

Eight-Element Communication Model for Internet Health Rumors: A New Exploration of Lasswell's "5W Communication Model".

(1) Background: Rumors are a special type of information. Based on the classic theory of the communication of information, the "5W" communication model, this article aims to build a new model and thus explains the generation and communication of Internet health rumors. (2) Methods: The authors selected 50 Internet health rumors, which were widely spread in widely used websites and social media in China, then grounded theory is used to perform the qualitative analysis of the Internet health rumors. (3) Results: Three Core Concepts are abstracted after qualitative analysis. An internal dynamic mutual assistance mechanism of the communication of rumors is built and illustrated. Based on Lasswell's "5W" communication model, the authors develop an eight-element communication model for Internet health rumors to illustrate the generation and communication of Internet health rumors. (4) Conclusions: By removing one or several elements of this new model, the chain of the communication of Internet health rumors could be cut off, which is valuable information for the government or websites to manage communication of Internet health rumors.

Preparation of magnesium Ferrite-Doped magnetic biochar using potassium ferrate and seawater mineral at low temperature for removal of cationic pollutants.

Magnetic biochar has captured a great interest for remediation of environment as an easily separable carbonous adsorbent. Herein, a highly adsorptive magnetic biochar was manufactured through seawater mineral and K2FeO4 co-promoted pyrolysis of jackfruit peel at 300 °C for removal of different cationic pollutants, and characterized by element analysis, FTIR, SEM-EDS, XRD, XPS and so on. MgFe2O4 was generated without external base and a 19.42 emu/g saturation magnetization was achieved. Simultaneously, iron oxides and oxygen containing groups were introduced. The magnetic biochar exhibited 61.30 mg/g, 129.61 mg/g, and 1238.30 mg/g adsorption capacities for Cu2+, methylene blue (MB), and malachite green (MG) at 25 °C, respectively, and remarkably surpassed the corresponding pristine biochar. The adsorption of MB and MG was mainly realized by electrostatic interaction, hydrogen bonding, complexation, and π-π electron-donor-acceptor interaction, and that of Cu2+ was attributed to electrostatic interaction, hydrogen bonding, and complexation.

A viral protein orchestrates rice ethylene signaling to coordinate viral infection and insect vector-mediated transmission.

Arthropod-borne viruses cause serious threats to human health and global agriculture by rapidly spreading via insect vectors. Southern rice black-streaked dwarf virus (SRBSDV) is the most damaging rice-infecting virus that is frequently transmitted by planthoppers. However, the molecular mechanisms underlying its propagation in the host plants and epidemics in the field are largely unknown. Here, we showed that the SRBSDV-encoded P6 protein is a key effector that regulates rice ethylene signaling to coordinate viral infection and transmission. In early SRBSDV infection, P6 interacts with OsRTH2 in the cytoplasm to activate ethylene signaling and enhance SRBSDV proliferation; this also repels the insect vector to reduce infestation. In late infection, P6 enters the nucleus, where it interacts with OsEIL2, a key transcription factor of ethylene signaling. The P6-OsEIL2 interaction suppresses ethylene signaling by preventing the dimerization of OsEIL2, thereby facilitating viral transmission by attracting the insect vector. Collectively, these findings reveal a novel molecular mechanism by which an arbovirus modulates the host defense system to promote viral infection and transmission.

Resistance Evaluation of Dominant Varieties against Southern Rice Black-Streaked Dwarf Virus in Southern China.

Southern rice black-streaked dwarf virus (SRBSDV), a Fijivirus in the Reoviridae family, is transmitted by the white-backed planthopper (Sogatella furcifera, WBPH), a long-distance migratory insect, and presents a serious threat to rice production in Asia. It was first discovered in China's Guangdong Province in 2001 and has been endemic in the south of China and north of Vietnam for two decades, with serious outbreaks in 2009, 2010, and 2017. In this study, we evaluated the resistance of 10 dominant rice varieties from southern China, where the virus overwinters and accumulates as a source of early spring reinfection, against this virus by artificial inoculation. The results showed that in all tested varieties there was no immune resistance, but there were differences in the infection rate, with incidence rates from 21% to 90.7%, and in symptom severity, with plant weight loss from 66.71% to 91.20% and height loss from 34.1% to 65.06%. Additionally, and valuably, the virus titer and the insect vector virus acquisition potency from diseased plants were significantly different among the varieties: an over sixfold difference was determined between resistant and susceptible varieties, and there was a positive correlation between virus accumulation and insect vector virus acquisition. The results can provide a basis for the selection of rice varieties in southern China to reduce the damage of SRBSDV in this area and to minimize the reinfection source and epidemics of the virus in other rice-growing areas.

Whole-exome sequencing reveals ANO8 as a genetic risk factor for intrahepatic cholestasis of pregnancy.

BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP) is characterized by pruritus and cholestasis in late pregnancy and results in adverse pregnancy outcomes, including preterm delivery and birth weight, which are affected by the genetic and environmental background. However, until now, the genetic architecture of ICP has remained largely unclear. METHODS: Twenty-six clinical data points were recorded for 151 Chinese ICP patients. The data generated from whole-exome sequencing (WES) using the BGISEQ-500 platform were further analyzed by Burrows-Wheeler Aligner (BWA) software, Genome Analysis Toolkit (GATK), ANNOVAR tool, etc. R packages were used to conduct t-test, Fisher's test and receiver operating characteristic (ROC) curve analyses. RESULTS: We identified eighteen possible pathogenic loci associated with ICP disease in known genes, covering ABCB4, ABCB11, ATP8B1 and TJP2. The loci Lys386Gln, Gly527Gln and Trp708Ter in ABCB4, Leu589Met, Gln605Pro and Gln1194Ter in ABCB11, and Arg189Ser in TJP2 were novel discoveries. In addition, WES analysis indicated that the gene ANO8 involved in the transport of bile salts is newly identified as associated with ICP. The functional network of the ANO8 gene confirmed this finding. ANO8 contained 8 rare missense mutations that were found in eight patients among the 151 cases and were absent from 1029 controls. Out of the eight SNPs, 3 were known, and the remaining five are newly identified. These variants have a low frequency, ranging from 0.000008 to 0.00001 in the ExAC, gnomAD - Genomes and TOPMED databases. Bioinformatics analysis showed that the sites and their corresponding amino acids were both highly conserved among vertebrates. Moreover, the influences of all the mutations on protein function were predicted to be damaging by the SIFT tool. Combining clinical data, it was found that the mutation group (93.36 µmol/L) had significantly (P = 0.038) higher total bile acid (TBA) levels than the wild-type group (40.81 µmol/L). CONCLUSIONS: To the best of our knowledge, this is the first study to employ WES technology to detect genetic loci for ICP. Our results provide new insights into the genetic basis of ICP and will benefit the final identification of the underlying mutations.

Ion-imprinted thermosensitive chitosan derivative for heavy metal remediation.

Ion-imprinted thermosensitive chitosan derivative (ITC) was successfully synthesized through a novel gradient heating process towards applications in heavy metal remediation, using Cu2+ template paired with N-isopropylacrylamide (NIPAM) monomer. SEM, DSC, FTIR and Raman spectroscopy were used to characterize the structure and properties of ITC. The phase change temperature (PCT) of ITC was 35.31 °C in the heating cycle, whereas in the cooling cycle the PCT for ITC was 26.27 °C. The adsorption capacity of ITC for Cu2+ at 45 °C (> PCT) was 88.94 mg/g. Desorption rate of 98.90 % was achieved after washing with ultra-pure water at 20 °C (< PCT). An adsorption capacity of 85 mg/g and a desorption rate of 97 % sustained after five cycles reuse. The adsorption capacity for Cu2+ was measured at 80.23 mg/g under other seven interfering metal ions. The adsorption kinetics and adsorption isotherm fitted pseudo-second-order and Langmuir equation, respectively.

Optimization of ultrasonic-assisted extraction and radical-scavenging capacity of phenols and flavonoids from Clerodendrum cyrtophyllum Turcz leaves.

Ultrasonic-assisted extraction (UAE) was developed to extract phenolic and flavonoid antioxidants from Clerodendrum cyrtophyllum Turcz leaves. The optimal experimental parameters for antioxidant extraction from C. cyrtophyllum leaves were measured using single-factor experimentation combined with response surface methodology (RSM). Total phenolic content (TPC) and total flavonoid content (TFC) assays were used to quantify antioxidant compounds. Next, antioxidant radical scavenging capacity was measured using 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and 2,2' -azino-bis(3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) radicals. Optimized extraction conditions for UAE from C. cyrtophyllum leaves were as follows: 60.9% ethanol, 85.4 min, and 63.3°C for maximal TPC extraction (16.8 ± 0.2 mg GAE/g DW); 67.7% ethanol, 82.9 min, and 63.0 °C for maximal TFC extraction (49.3 ± 0.4 mg RT/g DW); 48.8% ethanol, 85.1 min, and 63.9 °C for maximal DPPH radical-scavenging capacity (86.8 ± 0.2%); and 50.6% ethanol, 81.3 min, and 63.4 °C for maximal ABTS radical-scavenging capacity (92.9 ± 0.5%). Ethanol concentration was the most important factor in the extraction process. Our work offers optimal extraction conditions for C. cyrtophyllum as a potential source of natural antioxidants.