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In this paper, for a batch of existing data related to ancient glass objects in China, by analyzing the relationship between the basic information of cultural relics and the information of chemical composition detected by cultural relics, a prediction model that can predict the chemical composition data before weathering by the chemical composition data after weathering is established, a classification model based on the existing data is built to simulate the original classification law, and the model is used to identify the type of unclassified cultural relics, and then by The importance of the feature selects barium oxide as a criterion for subcategory classification. The proportion of chemical composition of the classified glass artifacts was determined by feature engineering to determine whether the 0 in the detection data was filled in artificially, and it was used as a new feature to reduce the impact of extreme data 0 on the model. The data were then used for model training to obtain the LightGBM classification model. The mean value of the chemical components with the highest feature importance in the model was selected as the criterion for subclass classification, and the values in each class were divided into 2 subclasses. The chemical components with the top 3 feature importance were subjected to sensitivity analysis, and sensitivity judgments were made by the indicators of the model. After first performing feature engineering on the data information of the unknown category of artifacts, the type identification output results were performed using the classification model built in Problem 2. The top 3 chemical components of importance in the model were selected to let their values fluctuate up and down by 5%, and the model indicator curves were plotted for sensitivity analysis.

Background: A large body of evidence shows that insufficient trophoblast invasion and proliferation contributes to the pathogenesis of fetal growth restriction (FGR). Circular RNAs (circRNAs) were recently recognized to have a part in regulating the trophoblast function. We aim to elucidate the role of circRNAs underlying the development of FGR. Methods: The expression of circRNAs in placenta tissues with and without FGR were identified using next generation sequencing (NGS). In vitro experiments including transfection, qRT-PCR, western blotting, immunofluorescence staining, dual-luciferase assays, cell invasion and migration assays were performed. Results: We found that 18 circRNAs were differentially expressed between the FGR placentas and uncomplicated pregnancies, while the expression of hsa-circ-0005238 was significantly lower in the FGR placentas. Our in vitro experiments further showed that hsa-circ-0005238 inhibited apoptosis and promoted migration, invasion of trophoblast cell lines. The hsa-miR-370-3p was identified as a direct target of hsa-circ-0005238. Mechanistically, hsa-miR-370-3p inhibits invasion and migration of trophoblast cells by suppressing the expression of CDC25B. Conclusions: The findings of the present study suggest that hsa-circ-0005238 play an important role in the pathogenesis of FGR by suppressing trophoblast cell invasion and migration through sponging hsa-miR-370-3p, which may provide new insight into therapeutic target for FGR.

In the application of wireless sensor networks, It is very important to determine the position of nodes themselves. In recent years, the research of node localization in wireless sensor networks based on intelligent optimization algorithm has attracted much attention. Sparrow search algorithm is a new intelligent optimization algorithm. In this paper, it is applied to the localization of wireless sensor network for the first time, and proposed a novel WSNs localization algorithm. The simulation results show that, compared with similar algorithms, the algorithm proposed in this paper not only achieves higher localization accuracy, but also shows better anti ranging error performance, and requires fewer anchor nodes for the same localization accuracy.

Background Fetal growth restriction (FGR) is a major cause of fetal and neonatal morbidity and mortality. Since meconium microbiome is a critical component for the health of newborns, the aim of this study was to characterize the meconium microbiota in neonates with FGR compared with healthy controls. Methods To avoid bacteria contamination, all included neonates were delivered by elective C-section, with their samples collected in the operation room. We collected meconium samples from 14 neonates affected by FGR and 20 matched healthy newborns. The microbiome profiles were examined by using high-throughput 16S rRNA sequencing and analyzed with customized bioinformatics pipelines. Results The β-diversity analysis demonstrated that FGR neonates clustered together that was distinct from control subjects. A number of taxa were found to be significantly depleted (e.g., Chryseobacterium) or enriched (e.g., Asticcacaulis) in the FGR group. In addition, the coordination network between various intestinal bacteria was found to be altered in FGR neonates. Conclusions FGR neonates exhibited alterations in the composition and symbiosis of microbiome, which will contribute to a better understanding of the relationship between the gut microbiota and FGR.

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a highly pathogenic tick-borne bunyavirus that causes lethal infectious disease and severe fever with thrombocytopenia syndrome (SFTS) in humans. The molecular mechanisms and host cellular factors required for SFTSV infection remain uncharacterized. Using a genome-wide CRISPR-based screening strategy, we identified a host cellular protein, sorting nexin 11 (SNX11) which is involved in the intracellular endosomal trafficking pathway, as an essential cell factor for SFTSV infection. An SNX11-KO HeLa cell line was established, and SFTSV replication was significantly reduced. The glycoproteins of SFTSV were detected and remained in later endosomal compartments but were not detectable in the endoplasmic reticulum (ER) or Golgi apparatus. pH values in the endosomal compartments of the SNX11-KO cells increased compared with the pH of normal HeLa cells, and lysosomal-associated membrane protein 1 (LAMP1) expression was significantly elevated in the SNX11-KO cells. Overall, these results indicated that penetration of SFTSV from the endolysosomes into the cytoplasm of host cells was blocked in the cells lacking SNX11. Our study for the first time provides insight into the important role of the SNX11 as an essential host factor in the intracellular trafficking and penetrating process of SFTSV infection via potential regulation of viral protein sorting, membrane fusion, and other endocytic machinery. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12250-019-00141-0) contains supplementary material, which is available to authorized users.

What is already known on this topic? Hemorrhagic fever with renal syndrome (HFRS) is endemic in Liaoning Province. Both Seoul and Hantaan virus are circulating in rodents, and epidemic outbreaks and sporadic cases have been recorded every year since the disease was recognized. What is added by this report? The epidemic trend of HFRS over the past 20 years (1999–2018) in Liaoning was analyzed, which showed both regional complexity and consistence with the epidemic in China. Genetic and antigenic stability of the circulating hantavirus were demonstrated, which suggested the effectiveness of the approved inactivated vaccine currently used in China. What are the implications for public health practice? Precise risk-based strategic practices that are integrated and regional are required for further improvement of the prevention and control of HFRS.

Background Hantaan and Seoul viruses, in the Hantavirus genus, are known to cause hemorrhagic fever with renal syndrome (HFRS). The plaque reduction neutralization test (PRNT), as conventional neutralization test for hantaviruses, is laborious and time-consuming. Alternatives to PRNT for hantaviruses are required. Methods In this study, the methods for Hantaan and Seoul viruses serological typing including microneutralization test (MNT), pseudoparticle neutralization test (PPNT) and immunofluorescence assay based on viral glycoproteins (IFA-GP) were developed and compared with PRNT using a panel of 74 sera including 44 convalescent sera of laboratory confirmed HFRS patients and 30 patients sera of non-hantavirus infection. Antibody titres and serotyping obtained with different methods above were analyzed by paired-t, linear correlation, McNemar χ2 and Kappa agreement tests. Results Antibody titres obtained with MNT50, PPNT50 and IFA-GP were significantly correlated with that obtained with PRNT50 (p 0.05) and less than (p 0.05). IFA-GP was less sensitive than PRNT50 and MNT50 for serotyping of hantaviruses infection (p

Zika virus (ZIKV) is a reemerging flavivirus that stroke Brazil in 2015 and appeared in China for the first time in 2016. Sequencing and genomic analysis are essential for Zika virus study. However, the complete genome length of Zika virus is still a disputable issue. In this study, we reported the complete genomic sequence of Zika virus strain ZKC2/2016 from an imported case in China, in February 2016. The virus was isolated and virus characteristics were identified by cytopathic effect, quantitative real time-PCR, immunofluorescence assay and electronic microscopy. Next generation sequencing (NGS) technique and 5' and 3' Rapid Amplification cDNA Ends (RACE) PCR were used to sequence the complete genome. The genome length of this newly obtained Zika virus strain is 10,807base pairs (bp). Genetic analysis showed that ZKC2/2016, along with other Chinese Zika virus strains in 2016, formed three clusters within Asian linage. Multiple sequence alignment and prediction of RNA secondary structure of untranslated regions (UTRs) of ZKC2/2016 and several other ZIKV strains indicated that the difference of ZIKV genome length mainly laid in UTRs. Besides, those genomes shorter than 10,790bp were probably incomplete due to lacking conserved secondary RNA structures in untranslated regions which were playing important roles in flavivirus replication. Our findings benefited the disease control of Zika fever in China and the study of Zika virus genome.

Background Severe fever with thrombocytopenia syndrome (SFTS) is a newly identified severe infectious disease caused by SFTS phlebovirus (SFTSV). SFTS monitoring has been carried out since 2010 in mainland China. We analysed the detection results of SFTSV RNA and antibody in SFTS surveillance cases to provide basic data for SFTS diagnosis. Methods This study was conducted in Shandong Province. Sera of SFTS surveillance cases were collected to detect SFTSV RNA and antibody by real-time RT-PCR and enzyme-linked immunosorbent assay, respectively. Detection rates were calculated. SPSS 18.0 (Chicago, IL, USA) was used for statistical analysis to compare the detection rates of SFTSV RNA and antibodies among different sera groups. Results A total of 374 SFTS surveillance cases were enrolled. Overall, 93.3% (349/374) of the sera samples were collected within 2 weeks after onset, and 6.7% (25/374) were collected between 15 days and 45 days. Of these, 183 (48.9%) were positive for SFTSV RNA. The SFTSV RNA-positive rate peaked (52.2%) in samples collected ≤7 days after onset and then showed a decreasing trend. The detection rate of SFTSV-specific IgM antibody was 30.5% (46/151) and was highest in samples collected between 8 and 14 days (43.3%, 26/60). The positive rate of SFTSV-specific IgG antibody (17.9%, 27/151) showed an increasing trend with the specimen collection time. In total, 74.8% (113/151) of sera samples had the same SFTSV RNA and IgM antibody detection results. However, 23.2% (29/125) of SFTSV RNA-negative cases were IgM antibody-positive, and 8.6% (9/105) of IgM antibody-negative cases were SFTSV RNA-positive. Conclusions SFTSV RNA detection was preferred for SFTSV infection during disease surveillance. For highly suspected SFTS cases, IgM antibody is suggested to make a comprehensive judgement.

CONSORT flowchart of the study. (PDF 210 kb)

The Hardy-Weinberg equilibrium of the two IL-27 polymorphisms. (DOCX 12 kb)

The prevalent comorbidities of patients with sepsis. (DOCX 13 kb)

Viral hemorrhagic fevers (VHFs) are worldwide diseases caused by several kinds of viruses. With the emergence of new viruses, advanced diagnostic methods are urgently needed for identification of VHFs. Based on Luminex xMAP technology, a rapid, sensitive, multi-pathogen and high-throughput method which could simultaneously detect hemorrhagic fever viruses (HFVs) specific IgG antibodies was developed. Recombinant antigens of nine HFVs including Hantaan virus (HTNV), Seoul virus (SEOV), Puumala virus (PUUV), Andes virus (ANDV), Sin Nombre virus (SNV), Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), Severe fever with thrombocytopenia syndrome bunyavirus (SFTSV) and dengue virus (DENV) were produced and purified from a prokaryotic expression system and the influence of the coupling amount was investigated. Cross-reactions among antigens and their rabbit immune sera were evaluated. Serum samples collected from 51 laboratory confirmed hemorrhagic fever with renal syndrome (HFRS) patients, 43 confirmed SFTS patients and 88 healthy donors were analyzed. Results showed that recombinant nucleocapsid protein of the five viruses belonging to the genus Hantavirus, had serological cross-reactivity with their corresponding rabbit immune sera, but not apparent with immune sera of other four viruses. Evaluation of this new method with clinical serum samples showed 98.04% diagnostic sensitivity for HFRS, 90.70% for SFTS detection and the specificity was ranging from 66.67% to 100.00%. The multiplexed Luminex-based immunoassay has firstly been established in our study, which provides a potentially reliable diagnostic tool for IgG antibody detection of VHFs.

Background. Severe fever with thrombocytopenia syndrome (SFTS) is an emerging viral disease in China, caused by SFTS virus (SFTSV). Severe SFTS patients can quickly proceed to multiorgan dysfunction and death; however, underlying pathogenic mechanisms remain unclear. Methods. Serum samples from 15 fatal and 44 nonfatal SFTS cases were subjected to multiplex-microbead immunoassays to detect a broad spectrum of cytokines. The viral load and virus-specific IgG titers were also tested by real-time PCR and ELISA, respectively. Results. Cytokines IL-1RA, IL-6, IL-10, G-CSF, IP-10, and MCP-1 were elevated in SFTS patients and produced at robust levels in fatal cases. In contrast, cytokines PDGF-BB and RANTES decreased in SFTS patients. These cytokines reverted to normal ranges during the convalescent phase of SFTSV infection. Cytokines IL-1β, IL-8, MIP-1α, and MIP-1β showed a unique pattern of elevation in fatal cases but not in nonfatal cases. However, these cytokines increased in the convalescent phase of nonfatal SFTS cases. Our regression analysis revealed that the serum viral load correlated with these cytokines. Moreover, levels of these cytokines correlated with various clinical parameters and virus-specific IgG titers. Conclusion. The study demonstrates that SFTSV infection induces a cytokine storm with abnormally expressed cytokine profiles, which are associated with the disease severity.

Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by the SFTS virus (SFTSV) with an average fatality rate of 12%. The clinical factors for death in SFTS patients remain unclear. Methods Clinical features and laboratory parameters were dynamically collected for 11 fatal and 48 non-fatal SFTS cases. Univariate logistic regression was used to evaluate the risk factors associated with death. Results Dynamic tracking of laboratory parameters revealed that during the initial fever stage, the viral load was comparable for the patients who survived as well as the ones that died. Then in the second stage when multi-organ dysfunction occurred, from 7-13 days after disease onset, the viral load decreased in survivors but it remained high in the patients that died. The key risk factors that contributed to patient death were elevated serum aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and creatine kinase fraction, as well as the appearance of CNS (central nervous system) symptoms, hemorrhagic manifestation, disseminated intravascular coagulation, and multi-organ failure. All clinical markers reverted to normal in the convalescent stage for SFTS patients who survived. Conclusions We identified a period of 7-13 days after the onset of illness as the critical stage in SFTS progression. A sustained serum viral load may indicate that disease conditions will worsen and lead to death.

The discovery of an emerging viral disease, severe fever with thrombocytopenia syndrome (SFTS), caused by SFTS virus (SFTSV), has prompted the need to understand pathogenesis of SFTSV. We are unique in establishing an infectious model of SFTS in C57/BL6 mice, resulting in hallmark symptoms of thrombocytopenia and leukocytopenia. Viral RNA and histopathological changes were identified in the spleen, liver, and kidney. However, viral replication was only found in the spleen, which suggested the spleen to be the principle target organ of SFTSV. Moreover, the number of macrophages and platelets were largely increased in the spleen, and SFTSV colocalized with platelets in cytoplasm of macrophages in the red pulp of the spleen. In vitro cellular assays further revealed that SFTSV adhered to mouse platelets and facilitated the phagocytosis of platelets by mouse primary macrophages, which in combination with in vivo findings, suggests that SFTSV-induced thrombocytopenia is caused by clearance of circulating virus-bound platelets by splenic macrophages. Thus, this study has elucidated the pathogenic mechanisms of thrombocytopenia in a mouse model resembling human SFTS disease.

Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease recently identified to be caused by a novel bunyavirus (SFTSV). The clinical diagnosis is urgently needed to differentiate the disease from other infections. Objective To develop a sensitive quantitative real-time RT-PCR assay for rapid detection of SFTSV viral RNA and evaluate potential use for clinical diagnosis of SFTS. Study design Primers and probes were designed to target the L, M, and S segments of SFTSV, and standard curves were established based on serial dilutions of in vitro transcribed viral RNA or viral RNA extracts. The serum samples collected from 70 laboratory confirmed SFTS patients, 114 non-SFTS patients, and 400 healthy donors were analyzed. Results Based on three optimized primer–probe sets to detect L, M, S genes of SFTSV, the quantitative real-time RT-PCR assay could discriminate SFTSV infection from other vector-borne viral diseases in human with potential detection limit of 10 viral RNA copies/μl or 10 TCID 50 /ml virus load. Strong linear correlations ( r 2 >0.99) between the C t values and viral RNA standards over a liner range were obtained. The assay specificity was determined by sequence alignment and experimentally tested on various related viruses. Evaluation of the study method with clinical serum samples showed 98.6% clinical diagnostic sensitivity and over 99% specificity. Conclusion The quantitative real-time RT-PCR assay established in this study can be used as a reliable method for early diagnosis of SFTSV infection.

To understand the immunogenicity of purified inactivated severe fever with thrombocytopenia syndrome bunyavirus (SFTSV), concentration by ultrafiltration as well as molecular-sieve chromatography (MSC) were used for purification of inactivated SFTSVs. Inactivated viruses in purified samples were analyzed and identified by western blotting and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), the glycoprotein (GP) and nucleoprotein (NP) antigen titers of which were detected using a double-sandwich enzyme-linked immunosorbent assay (ELISA). Purified inactivated SFTSVs were enriched and observed by electron microscopy, and the total protein concentration detected using the bicinchoninic acid assay. Purified inactivated SFTSVs were applied to New Zealand rabbits via two immunization programs to evaluate immunogenicity and to compare the immune effect. After SFTSVs were inactivated and concentrated by ultrafiltration, MSC revealed two typical elution peaks. The sample of one peak was identified as inactivated virions, in which GP and NP were detected by SDS-PAGE, western blotting and ELISA. Main corponent of the other peak was NP. After concentration by ultrafiltration, purified inactivated SFTSVs with purity90% and total protein concentration of 1. 1 mg/mL were obtained, and the typical electron microscopy of bunyavirus was observed. In the sera of animals immunized with purified inactivated SFTSVs, SFTSV-specific IgG antibody and neutralizing antibody were detected at high titers. However, antibody titers were affected by the immunization program. Effect of immunization on days 0, 14 and 28 was significantly better than that on days 0, 7 and 28. Our work revealed that cultivation of SFTSVs contained intact virus particles and large amounts of free NP. Using MSC, purified inactivated SFTSVs of high purity could be obtained. Purified inactivated SFTSVs induced high titers of neutralizing antibody and virus-specific IgG antibody showing satisfactory immunogenicity, which provides important clues for further study on a vaccine for the inactivated virus.

To explore a new method for stable expression of virus-like particles (VLPs) of the severe fever with thrombocytopenia syndrome (SFTS) virus, an expression plasmid for the membrane glycoprotein (GP) and nucleocapsid protein (NP) of the SFTS virus was constructed by fusion of the two proteins via a serine residue, and a yellow fluorescence protein (YFP) gene was introduced into the plasmid as a reporter. CHO-K1 cells were transfected with this plasmid, and stable cell lines constructed using the limited dilution method. Cellular colonies were hand-picked based on YFP with the help of fluorescence microscopy and expanded without selection pressure. Stability of cell lines was evaluated by monitoring of fluctuation of the intensity of YFP for 40 passages. VLP production was characterized using an indirect fluorescence assay, immunoblotting, and electronic microscopy. We showed that GP and NP fusion proteins could be assembled into VLPs in vivo, and that VLPs had similar morphologies to virus particles. Selected cell lines were stable for YFP expression: no significant fluctuation was detected in 40 passages. These data demonstrated the effectiveness of this new method for expression of structural proteins of the SFTS virus and screening for stable cell lines. Our results could provide new concepts for the production of biopharmaceuticals.

Severe fever with thrombocytopenia syndrome bunyavirus is a newly discovered bunyavirus with high pathogenicity to human. The transmission model has been largely uncharacterized. Investigation on a cluster of severe fever with thrombocytopenia syndrome cases provided evidence of person-to-person transmission through blood contact to the index patient with high serum virus load.

A safe and effective hantavirus vaccine is highly desirable since hantaviruses are distributed worldwide and cause an acute and often fatal disease (hemorrhagic fever with renal syndrome, HFRS). Virus-like particles (VLPs) displaying functional viral proteins could provide effective vaccines against a few viruses, but their ability to induce hantavirus-specific immune response has not been adequately investigated. To measure the immunogenicity of Hantaan virus-like particles (HTN-VLPs) vaccine, we generated recombinant HTN-VLPs by co-expressing Hantaan virus nucleocapsid (N) protein and glycoproteins (Gn and Gc) in Chinese hamster ovary (CHO) cells. We compared intramuscular versus subcutaneous administration of HTN-VLPs for the ability to induce specific immune response against Hantaan virus infection. Mice that received both intramuscular and subcutaneous immunizations of HTN-VLPs were sufficiently stimulated specific antibody response against Hantaan virus N protein and glycoproteins, which was comparable to Chinese commercial inactivated bivalent hantaviruses vaccine. Moreover, vaccination with HTN-VLPs also resulted in the induction of higher levels of specific cellular response to N protein than that of inactivated vaccine. Our results provide an important insight towards the development of hantaviruses-like particles as a potential candidate vaccine for the control and prevention of hantaviruses infection.

To prepare monoclonal antibodies (mAbs) against structural proteins of severe fever with thrombocytopenia syndrome bunyavirus (SFTSV), BALB/c mice were immunized using purified inactivated SFTSV virions as the antigens. Subsequently, hybridoma cell lines that secreted monoclonal antibodies against nucleoprotein (NP) and glycoproteins (GP) were obtained using a hybridoma technique. The antigen specificities of prepared mAbs were examined by indirect immunofluorescence and immunoprecipitation assays. Functional analyses were then performed,including the detection of IFA antibody titers,the levels of neutralizing activity and antibody affinities. After cell fusion and cloning,13 hybridoma cell lines secreted mAbs specifically against SFTSV-GP and 7 hybridoma cell lines secreted mAbs specifically against SFTSV-NP. Immunofluorescence and immunoprecipitation assays showed that the mAbs had high levels of antigen specificity. Among the 13 anti-SFTSV-GP mAbs,6 recognized Gn,whereas the others reacted with Gc. IFA titers of most anti-SFTSV-GP mAbs were between 1,280 and 20,480, and four anti-SFTSV-Gn mAbs showed neutralizing activity. Seven of the obtained anti-SFTSV-NP mAbs reacted specifically with NP,of which the IFA titers ranged from 5,120 to 20,480 with no observed neutralizing activity. Furthermore, two anti-SFTSV-GP mAbs, 1C8 and 1G8, showed high levels of affinity via a non-competitive ELISA. Our study lays the foundation for the development of further diagnostic assays and basic research into SFTSV.

Transgenic mice expressing a recombinant human monoclonal antibody (rHMAb) against hantavirus were generated. These mice could be used as models to explore the possibilities of producing rHMAbs for therapeutic purposes. The highest concentration of the rHMAb in the milk of the transgenic females was 6.6 mg/ml. The rHMAb was also detected in the sera of pups fed by the transgenic females. Both the rHMAbs in the milk of transgenic mice and those in the sera of suckling pups were found to be active against hantaviruses, although the light chain of the antibody absorbed by the pups was modified by N-linked glycosylation.

SFTS virus (SFTSV) is a highly pathogenic bunyavirus that causes severe fever with thrombocytopenia syndrome (SFTS), an emerging infectious disease in China. Laboratory mice have been reported to be susceptible to SFTSV infection, but the infection in nonhuman primates has not been investigated. This study is the first to report that, in rhesus macaques, SFTSV does not cause severe symptoms or death but causes fever, thrombocytopenia, leukocytopenia, and increased levels of transaminases and myocardial enzymes in blood. Viremia, virus-specific immunoglobulin M and immunoglobulin G antibodies, and neutralizing antibodies were identified in all infected macaques. Levels of the cytokines interferon γ, eotaxin, tumor necrosis factor α, and macrophage inflammatory protein 1β were significantly elevated in the blood. Minor pathological lesions were observed in the liver and kidney during the late stages of infection. Overall, SFTSV infection in rhesus macaques resembled mild SFTS in humans.

It is critical to develop a cost-effective detection kit for rapid diagnosis and on-site detection of severe fever with thrombocytopenia syndrome virus (SFTSV) infection. Here, an immunochromatographic assay (ICA) to detect SFTSV infection is described. The ICA uses gold nanoparticles coated with recombinant SFTSV for the simultaneous detection of IgG and IgM antibodies to SFTSV. The ICA was developed and evaluated by using positive sera samples of SFTSV infection(n=245)collected from the CDC of China. The reference laboratory diagnosis of SFTSV infection was based on the “gold standard”. The results demonstrated that the positive coincidence rate and negative coincidence rate were determined to be 98.4% and 100% for IgM and 96.7% and 98.6% for IgG, respectively. The kit showed good selectivity for detection of SFTSV-specific IgG and IgM with no interference from positive sera samples of Japanese encephalitis virus infection, Dengue virus infection, Hantavirus infection, HIV infection, HBV surface antigen, HCV antibody,Mycobacterium tuberculosisantibody, or RF. Based on these results, the ICS test developed may be a suitable tool for rapid on-site testing for SFTSV infections.

In total, 3,145 ticks of the species Haemaphysalis longicornis (3,048; 96.9%), R. microplus (82; 2.6%), H. campanulata (9; 0.3%), and Dermacentor sinicus (5; 0.2%) were collected from animals and vegetation at Yantai in Shandong Province. Both adult and immature ticks were obtained, and all ticks collected from vegetation were unfed. Eggs were obtained from 22 blood-fed female ticks through maintenance at room temperature after collection. Severe fever with thrombocytopenia syndrome virus (SFTSV) viral RNA was identified in H. longicornis and R. microplus, with a prevalence of 4.75 per 100 ticks (95% confidence interval [95% CI] = 3.87-5.63) for ticks collected from animals and 2.24 per 100 ticks (95% CI = 1.27-3.21) for ticks collected from vegetation. The possibility that SFTSV transmission may occur by both the transstadial and transovarial routes was suggested by the fact that viral RNA was detected in H. longicornis at all developmental stages. Tick-derived sequences shared over 95.6% identity with human- and animal-derived isolates. This study provides evidence that implicates ticks as not only vectors but also, reservoirs of SFTSV.

BACKGROUND: Viral hemorrhagic fevers (VHFs) are a group of animal and human illnesses that are mostly caused by several distinct families of viruses including bunyaviruses, flaviviruses, filoviruses and arenaviruses. Although specific signs and symptoms vary by the type of VHF, initial signs and symptoms are very similar. Therefore rapid immunologic and molecular tools for differential diagnosis of hemorrhagic fever viruses (HFVs) are important for effective case management and control of the spread of VHFs. Real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) assay is one of the reliable and desirable methods for specific detection and quantification of virus load. Multiplex PCR assay has the potential to produce considerable savings in time and resources in the laboratory detection. RESULTS: Primers/probe sets were designed based on appropriate specific genes for each of 28 HFVs which nearly covered all the HFVs, and identified with good specificity and sensitivity using monoplex assays. Seven groups of multiplex one-step real-time qRT-PCR assays in a universal experimental system were then developed by combining all primers/probe sets into 4-plex reactions and evaluated with serial dilutions of synthesized viral RNAs. For all the multiplex assays, no cross-reactivity with other HFVs was observed, and the limits of detection were mainly between 45 and 150 copies/PCR. The reproducibility was satisfactory, since the coefficient of variation of Ct values were all less than 5% in each dilution of synthesized viral RNAs for both intra-assays and inter-assays. Evaluation of the method with available clinical serum samples collected from HFRS patients, SFTS patients and Dengue fever patients showed high sensitivity and specificity of the related multiplex assays on the clinical specimens. CONCLUSIONS: Overall, the comprehensive multiplex one-step real-time qRT-PCR assays were established in this study, and proved to be specific, sensitive, stable and easy to serve as a useful tool for rapid detection of HFVs.

To investigate the infections of severe fever with thrombocytopenia syndrome virus (SFTSV) in domesticated animals, we sampled a total of 3,039 animals in 2 counties in Shandong Province, People’s Republic of China, from April to November 2011. SFTSV-specific antibodies were detected in 328 (69.5%) of 472 sheep, 509 (60.5%) of 842 cattle, 136 (37.9%) of 359 dogs, 26 (3.1%) of 839 pigs, and 250 (47.4%) of 527 chickens. SFTSV RNA was detected in all sampled animal species, but the prevalence was low, ranging from 1.7% to 5.3%. A cohort study in 38 sheep was conducted to determine when seroconversion to SFTSV occured. SFTSVs were isolated from sheep, cattle, and dogs and shared >95% sequence homology with human isolates from the same disease-endemic regions. These findings demonstrate that natural infections of SFTSV occur in several domesticated animal hosts in disease-endemic areas and that the virus has a wide host range.

Background The incidence of dengue, an infectious disease caused by dengue virus (DENV), has dramatically increased around the world in recent decades and is becoming a severe public health threat. However, there is currently no specific treatment for dengue fever, and licensed vaccine against dengue is not available. Vaccination with virus-like particles (VLPs) has shown considerable promise for many viral diseases, but the effect of DENV VLPs to induce specific immune responses has not been adequately investigated. Results By optimizing the expression plasmids, recombinant VLPs of four antigenically different DENV serotypes DENV1-4 were successfully produced in 293T cells. The vaccination effect of dengue VLPs in mice showed that monovalent VLPs of each serotype stimulated specific IgG responses and potent neutralizing antibodies against homotypic virus. Tetravalent VLPs efficiently enhanced specific IgG and neutralizing antibodies against all four serotypes of DENV. Moreover, vaccination with monovalent or tetravalent VLPs resulted in the induction of specific cytotoxic T cell responses. Conclusions Mammalian cell expressed dengue VLPs are capable to induce VLP-specific humoral and cellular immune responses in mice, and being a promising subunit vaccine candidate for prevention of dengue virus infection.

Conventional multi-view video coding (MVC) requires high encoding complexity and high rate data transmission from cameras to a joint encoder. Distributed coding theories guarantee that low complexity and independent encoders can achieve similar coding efficiency as traditional methods. However, there is still a big performance gap between current distributed multi-view video coding (DMVC) schemes and conventional schemes. In this paper, we propose a novel distributed residual coding framework for multi-view video with joint motion vector projection (MVP) and 3-D warping. At the encoder, by means of the improved block classification, distributed residual coding is performed effectively to help reduce temporal redundancy. At the decoder, a joint motion vector projection and 3-D warping method is proposed to generate the candidates of side information and two binary fusion masks. Finally, we employ a novel fusion criterion with relation to the reliability of side information acquisition measures. Experimental results show that the proposed DMVC framework has achieved both side information quality and rate distortion performance improvement.