In 2012, an unprecedented large-scale outbreak of disease in pigs in China caused great economic losses to the swine industry. Isolates from pseudorabies virus epidemics in swine herds were characterized. Evidence confirmed that the pathogenic pseudorabies virus was the etiologic agent of this epidemic.

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bHighly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) continues to evolve when serially passaged in Marc-145 cells. In this study, we analyzed the genomic and antigenic variants of HP-PRRSV strain JXA1 during in vitro passage. Protective efficacies of JXA1 from passages 100, 110, 120, 140, and 170 against the high-virulence parental virus were evaluated by inoculating pigs with each of these viruses and then challenging with JXA1 from passage 5 at 28 days postimmunization. We found that the antigenicities of JXA1 from passages after 110 were significantly reduced. Inoculation with JXA1 from passages after 110 provided only insufficient protection against the parental strain challenge, indicating that the immunogenicity of JXA1 is significantly decreased when it is in vitro passaged for 110 times and more. To identify the genomic variants that emerged during the overattenuation, eight complete genomes of highly passaged JXA1 were sequenced. One guanine deletion in the 5= untranslated region (UTR), two nucleotide substitutions in the 3= UTR, and 65 amino acid mutations in nonstructural and structural proteins that accompanied with the attenuation and overattenuation were determined. Genomic sequencing of in vitro serially passaged HP-PRRSV first identified the mutations potentially correlated with the overattenuation of a HP-PRRSV strain. These results facilitate the research aimed at elucidating the mechanisms for PRRSV genomic and antigenic changes and may also contribute to developing a safe and effective PRRSV vaccine.

The safety and efficacy of the JXA1-R vaccine, an attenuated strain of highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV), were examined using an intramuscular challenge model in piglets. The JXA1-R vaccine was obtained by passing HP-PRRSV JXA1 through Marc-145 cells (82nd passage). Genomic sequence comparisons showed that strain JXA1-R and its parental strain, JXA1, differ by 47 amino acids, and most of these differences are scattered throughout the PRRSV genome. Four-week-old PRRSV-free piglets were inoculated intramuscularly with JXA1-R vaccine (10 3.0 , 10 4.0 , 10 5.0 , 10 6.0 , and 10 7.0 50% tissue culture infective doses [TCID 50 ]/ml for groups 1 to 5, respectively) and then challenged intramuscularly with the 5th passage virus of JXA1 virus (JXA1-F5, 3 ml ؋ 10 4.5 TCID 50 /ml) 28 days after inoculation. The humoral immune response, swine growth, clinical signs, and differential organ lesions were monitored. The results showed that all vaccinated piglets had a perceptible humoral immune response to vaccination after day 7, which then promptly increased, almost reaching the maximum sample/positive (S/P) ratio value at 28 days postimmunization. Viremia detection indicated that the viral replication levels of the challenge virus in the immunized groups (immunization doses >104.0 /ml) were significantly lower than that of the virus-challenged unvaccinated control group. Piglets in groups 2 to 5 were effectively protected against lethal HP-PRRSV infection and did not show any obvious changes in body temperature or clinical signs of disease at any point during the experiment. However, two of five piglets in group 1 showed mild pathological lesions and transitory high fever. These results suggest that JXA1-R (TCID 50 /ml >10 4.0 ) is sufficiently attenuated and can provide effective protection against the lethal wild-type HP-PRRSV. P orcine reproductive and respiratory syndrome (PRRS) was first discovered in the United States in 1987 (1, 2). It is characterized by reproductive failure in pregnant sows and respiratory disorder in growing swine. PRRS has spread through most of the world's swine-producing regions and has caused substantial economic losses to the swine industry worldwide.PRRS virus (PRRSV) is the causative agent of PRRS. It is a single-stranded, positive-sense RNA virus belonging to the family Arteriviridae, order Nidovirales (3, 4). The viral genome is approximately 15 kb in size and contains 10 open reading frames (ORFs), designated ORF1a, ORF1b, ORF2a, ORF2b, ORF3, ORF4, ORF5a, ORF5, ORF6, and ORF7 (5-8). Among these ORFs, ORF1a encodes 9 nonstructural proteins (NSPs), including NSP1␣, NSP1␤, and NSP2 to NSP8; ORF1b encodes NSP9 to NSP12. ORF1a and ORF1b encode the viral nonstructural proteins, which are involved in viral replication and transcription. ORF2a, ORF2b, and ORFs 3 to 7 encode the viral structural proteins GP2, E, GP3, GP4, GP5a, GP5, M, and N, respectively (5-8). The ORF5a protein is a novel structural protein in PRRSV, which is encoded by an alternate...

Background The aim of this prospective study was to compare transcranial direct current stimulation (tDCS) plus electroacupuncture with standard analgesia in patients after total knee arthroplasty (TKA) to determine the effects on rehabilitation and functional recovery. Material/Methods Eighty patients with osteoarthritis of the knee who underwent TKA were included in the study. They were divided into experimental (n=40) and control groups (n=40) according to postoperative analgesia method. The control group received multimodal analgesia after TKA and the experimental group received additional tDCS plus electroacupuncture. Postoperative pain, knee function, and quality of life were compared between the 2 groups. Results Compared with the control group, the experimental group had significantly lower visual analog scale scores at 3 and 7 days and 3 and 6 weeks after TKA ( P <0.05). At 6 weeks after TKA, knee injury and osteoarthritis outcome and Hospital for Special Surgery scores and maximum knee flexion in the experimental group were significantly better than those in the control group ( P <0.05). In the experimental group compared with the control group, the Short Form-36 Health Survey score also was significantly increased ( P <0.05). Conclusions The findings from this study showed that tDCS plus electroacupuncture effectively reduced pain after TKA and improved rehabilitation and functional recovery.