Construction of and evaluation of the immune response to two recombinant pseudorabies viruses expressing the B119L and EP364R proteins of African swine fever virus.

African swine fever (ASF) is an infectious disease caused by ASF virus (ASFV), which is characterized by high infectivity, rapid onset of disease, and a high mortality rate. Outbreaks of ASFV have caused great economic losses to the global pig industry, and there is a need to develop safe and effective vaccines. In this study, two recombinant pseudorabies virus (PRV) strains, rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L, expressing the EP364R and B119L protein, respectively, of ASFV, were constructed by homologous recombination technology. Western blotting and immunofluorescence analysis showed that these foreign proteins were expressed in cells infected with the recombinant strains. The strains showed good genetic stability and proliferative characteristics for 20 passages in BHK-21 cells. Both of these strains were immunogenic in mice, inducing the production of specific antibodies against the expressed ASFV proteins while providing protection against lethal challenge with PRV. Thus, the recombinant strains rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L could be used as candidate vaccines for both ASFV and PRV. In addition, our study identifies two potential target genes for the development of safe and efficient ASFV vaccines, provides a reference for the construction of bivalent ASFV and PRV vaccines, and demonstrates the feasibility of developing a live ASFV vector vaccine.

Molecular epidemiological and genetic characterization of pseudorabies virus in Guangxi, China.

Pseudorabies virus (PRV) is an important pathogen that can cause harm to the pig population. Since 2011, there have been a number of large-scale outbreaks of pseudorabies on Chinese farms where animals had been vaccinated with the Bartha-K61 vaccine. In order to understand the epidemiological trend and genetic variations of PRV in Guangxi province, China, 819 tissue samples were collected from swine farms where PRV infection was suspected from 2013 to 2019, and these were tested for infectious wild strains of PRV. The results showed a positive rate of PRV in Guangxi province of 28.21% (231/819). Thirty-six wild-type PRV strains were successfully isolated from PRV-positive tissue samples, and a genetic evolutionary analysis was performed based on the gB, gC, gD, gE, and TK genes. Thirty of the PRV strains were found to be closely related to the Chinese variant strains HeN1-China-2012 and HLJ8-China-2013. In addition, five PRV strains were genetically related to Chinese classical strains, and one isolate was a recombinant of the PRV variant and the vaccine strain Bartha-K61. Amino acid sequence analysis showed that all 36 PRV strains had characteristic variant sites in the amino acid sequences of the gB, gC, gD, and gE proteins. Pathogenicity analysis showed that, compared to classical PRV strains, the PRV variant strains were more pathogenic in mice and had a lower LD50. Taken together, our results show that wild-type PRV infections are common on pig farms in Guangxi province of China and that the dominant prevalent strains were those of the PRV variants. The PRV variant strains also had increased pathogenicity in mice. Our data will provide a useful reference for understanding the prevalence and genetic evolution of PRV in China.

Isolation and identification of two novel pseudorabies viruses with natural recombination or TK gene deletion in China.

Pseudorabies virus (PRV), the causative agent of Aujeszky's disease, has gained increased attention in China in recent years due to outbreaks of emergent pseudorabies. However, there is limited information about the evolution and pathogenicity of emergent PRV field strains in China. In this study, two PRV field strains were isolated from an intensive pig farm with suspected PRV infection. These were named the GXLB-2015 and GXGG-2016 strains and their growth characteristics together with their genome sequences and pathogenicity were determined. Nucleotide homology and phylogenetic analysis revealed the GXLB-2015 stain was relatively close to the foreign PRV isolated strains with respect to the whole genome sequence. However, it formed an independent branch between the foreign PRV isolates and the previous PRV variants isolated in China. Further recombination and genetic evolution analysis showed that the GXLB-2015 strain was a natural recombinant between the Bartha strain and PRV variants. The GXGG-2016 strain was highly homologous with the Chinese classical strains, but it has a natural deletion of 69 aa in the thymidine kinase (TK) gene. Pathogenicity analysis showed that, the GXLB-2015 strain had the strongest pathogenicity to mice with an LD50 of 103.5, while the GXGG-2016 strain with the TK gene deletion was not pathogenic to mice. Taken together, our data provide direct evidence for the genomic recombination and natural TK gene deletion of PRVs, which may provide a reference for a better understanding of PRV evolution in China and contribute to the clinical control of PRV infection in pig farms.

Traffic Volatility Forecasting Using an Omnibus Family GARCH Modeling Framework.

Traffic volatility modeling has been highly valued in recent years because of its advantages in describing the uncertainty of traffic flow during the short-term forecasting process. A few generalized autoregressive conditional heteroscedastic (GARCH) models have been developed to capture and hence forecast the volatility of traffic flow. Although these models have been confirmed to be capable of producing more reliable forecasts than traditional point forecasting models, the more or less imposed restrictions on parameter estimations may make the asymmetric property of traffic volatility be not or insufficiently considered. Furthermore, the performance of the models has not been fully evaluated and compared in the traffic forecasting context, rendering the choice of the models dilemmatic for traffic volatility modeling. In this study, an omnibus traffic volatility forecasting framework is proposed, where various traffic volatility models with symmetric and asymmetric properties can be developed in a unifying way by fixing or flexibly estimating three key parameters, namely the Box-Cox transformation coefficient λ, the shift factor b, and the rotation factor c. Extensive traffic speed datasets collected from urban roads of Kunshan city, China, and from freeway segments of the San Diego Region, USA, were used to evaluate the proposed framework and develop traffic volatility forecasting models in a number of case studies. The models include the standard GARCH, the threshold GARCH (TGARCH), the nonlinear ARCH (NGARCH), the nonlinear-asymmetric GARCH (NAGARCH), the Glosten-Jagannathan-Runkle GARCH (GJR-GARCH), and the family GARCH (FGARCH). The mean forecasting performance of the models was measured with mean absolute error (MAE) and mean absolute percentage error (MAPE), while the volatility forecasting performance of the models was measured with volatility mean absolute error (VMAE), directional accuracy (DA), kickoff percentage (KP), and average confidence length (ACL). Experimental results demonstrate the effectiveness and flexibility of the proposed framework and provide insights into how to develop and select proper traffic volatility forecasting models in different situations.

Effect of different preoperative fasting time on safety and postoperative complications of painless gastrointestinal endoscopy for polyps in patients.

OBJECTIVE: To determine the effect of different preoperative fasting time on safety and postoperative complications of painless gastrointestinal endoscopy for polyps in patients. METHODS: Enrolled patients were assigned to an observation group and a control group by the random number table method (each n=68). Before operation, each patient in the observation group was fasted from solids for 6 h and from liquids for 2 h, while each one in the control group was fasted from solids for 8-12 h and from liquids for 4 h according to the conventional method. The levels of blood glucose, insulin, potassium and sodium in patients before and after operation were determined, and their hunger and thirst were recorded before anesthesia. Additionally, the incidences and degrees of vomiting and nausea among the patients after anesthesia and operation were recorded. RESULTS: Before operation, the observation group showed higher levels of blood glucose, insulin, serum potassium and serum sodium than the control group (all P<0.001), while after operation, the observation group showed lower levels of blood glucose and insulin and higher levels of serum potassium and serum sodium than the control group (all P<0.001). In addition, the degrees and incidences of hunger and thirst in patients of the observation group were significantly lower than those in the control group before operation (P<0.01), and the degrees and incidences of nausea and vomiting in the observation group were also notably lower than those in the control group before and after operation (both P<0.05). CONCLUSION: For patients undergoing painless gastrointestinal endoscopy for polyps, shortening their fasting time from solids and liquids before operation can stabilize their blood glucose, insulin and electrolyte levels before and after operation, relieve their thirst and hunger before operation, and reduce the incidences of postoperative nausea and vomiting.

Development of an in situ diagnostic system for mapping the deposition distribution on plasma facing components of the HL-2M tokamak.

The assessment of material deposition and fuel retention on Plasma Facing Components (PFCs) is of primary importance for the steady-state operations of future fusion devices. In this paper, an in situ diagnostic for mapping the deposition distribution (IMap) on a wide area of PFCs for HL-2M (Huan Liu Qi-2 Modification) is developed. The design, fabrication, integration, and lab test of the IMap have been implemented. This system is built with the laser-induced breakdown spectroscopy technique which is an in situ diagnostic technique to determine the constituents and the depth profile of deposition compositions on PFCs. With a molybdenum reflection mirror inside the chamber and its manipulator, the IMap system can scan from the inner wall across the lower divertor to the outer middle plane. The system can be remotely controlled, and its optical lenses, mirrors, and fibers can be adjusted automatically when scanning over the PFCs. Therefore, the wall properties over a wide area of the vessel can be measured. All elements with the emission lines in the range of 380-850 nm can be analyzed, and the isotope species H and D can also be identified clearly with this diagnostic. Moreover, the depth profiles of the deposited materials can be determined, and the fuel retention on PFCs can be evaluated in situ. This gives a clear picture of the deposition and retention over the wall of HL-2M.