In this study,the loop-mediated isothermal amplification(LAMP)method was used to develop a rapid and simple detection system for porcine circovirus type 2(PCV2).According to the PCV2 sequences published in GenBank,multiple LAMP primers were designed targeting conserved sequences of PCV2.Using the DNA extracted from PCV2 isolates HUN-09 and SD-09 as the template,LAMP reactions in a PCV2 LAMP system was performed,the amplification products were detected by adding SYBR Green I and could be observed directly by the naked eye.The results showed highly-efficient and specific amplification in 30 min at 63℃ with a LAMP real-time turbidimeter.Furthermore,PCV2 DNA templates,with a detection limit of 5.5×10-5ng of nucleic acid,indicated that this assay was highly sensitive.The results obtained with the naked eye after SYBR Green I staining were consistent with those detected by the real-time turbidimeter,showing the potential simplicity of interpretation of the assay results.The LAMP assay appeared to have greater accuracy than PCR and virus isolation for the analysis of 18 clinical samples.In addition it offers higher specificity and sensitivity,shorter reaction times and simpler procedures than the currently available methods of PCV2 detection.It is therefore a promising tool for the effective and efficient detection of PCV2.

A real-time monitoring reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for the sensitive and specific detection of prototypic,prevalent North American porcine reproductive and respiratory syndrome virus (PRRSV)strains.As a higher sensitivity and specificity method than reverse transcription polymerase chain reaction (RT-PCR),the RT-LAMP method only used a turbidimeter,exhibited a detection limit corresponding to a 10-4 dilution of template RNA extracted from 250 μL of 105 of the 50% tissue culture infective dose (TCID50) of PRRSV containing cells,and no cross-reactivity was observed with other related viruses including porcine circovirus type 2,swine influenza virus,porcine rotavirus and classical swine fever virus.From forty-two field samples,33 samples in the RT-LAMP assay was detected positive,whereas three of which were not detected by RT-PCR.Furthermore,in 33 strains of PRRSV,an identical detection rate was observed with the RT-LAMP assay to what were isolated using porcine alveolar macrophages.These findings demonstrated that the RT-LAMP assay has potential clinical applications for the detection of highly pathogenic PRRSV isolates,especially in developing countries.

Objective To explore the relationship between schizotypal personality proneness and intelligence .Methods 1905 subjects were tested by Chinese Soldier Personality Questionnaire(CSPQ).According to the results of CSPQ,the subjects were divided into high-risk subjects and normal ones.The Words Reasoning Test, the Arithmetic Reasoning Test and the Assembling Test were used to evaluate the intelligence,and the scores of these tests were compared between the two groups.Correlation coefficient between schizotypal personality proneness and intelligence was calculated.Results The scores of the Words Reasoning Test,the Arithmetic Reasoning Test and the Assembling Test in high-risk subjects were significantly lower than those in normal ones((87.83±18.42)VS(101.37±13.48),P<0.01;(91.74±14.26)vs(101.65±14.62),P<0.01;(87.70±18.82)VS (101.73±14.26),P<0.01).Schizotypal personality proneness was significantly correlated with the scores of intelligence(r=-0.39,P<0.01).Conclusion Lower intelligence level is found in the group with schizotypal personality proneness.Intelligence is correlated with schizotypal personality proneness.

Objective To investigate the clinical significance of serum interleukin-6(IL-6),C-reactive protein(CRP) and procalcitonin(PCT) in early diagnosis of postoperative infection after artificial femoral head replacement in rabbits.Methods Selected 64 healthy New Zealand white rabbits,and randomly divided them into the experimental group and the control group,with 32 cases in each group.All of the 64 rabbits underwent left femoral hip replacement.Rabbits in the experimental group were injected with staphylococcus aureus into the left hip joint immediately after artificial femoral head replacement,while rabbits in control group were injected with the same amount of saline.The changes of IL-6,CRP and PCT in synovial fluid of all rabbits were measured.Took synovial fluid and 3 pieces of synovial membrane to make bacterial culture 9 days after surgery.Results The bacterial culture of the experimental group was positive for staphylococcus aureus while it was negative in the control group.One day after surgery,the levels of IL-6,CRP and PCT in synovial fluid of two groups were significantly higher than those before operation(P<0.05),but the difference between the two groups was not statistically significant(P>0.05).The levels of IL-6,CRP and PCT in the synovial fluid of the experimental group were significantly higher than those of the control group at the 3rd,6th and 9th day after operation(P<0.05).There was a significant increase in IL-6,CRP and PCT levels in the two groups at the first and 3rd day after operation(P<0.05).At 6th days after operation,the levels of IL-6,CRP and PCT in synovial fluid of experimental group continued to increase(P<0.05),and they began to decrease in the control group (P<0.05).PCT gradually restored preoperative level at 6th days after operation(P>0.05),and IL-6 and CRP gradually restored preoperative level at 9th days after operation(P>0.05).The sensitivity and specificity of IL-6,CRP and PCT combined test were 96.9% and 90.6% respectively,which were significantly higher than those of individual indexes.Conclusion Combined detection of serum IL-6,CRP and PCT levels in the infection model of artificial femoral head replacement can provide some help for the early diagnosis of infection after clinical hip arthroplasty.

This paper aims to detect the antigens in porcine circovirus type 2 (PCV2) vaccines by high-performance size-exclusion chromatography (HPSEC) coupled with multi-angle laser light scattering (MALLS). With purified inactivated PCV2 and PCV2 virus-like particles (VLP) as references, two inactivated vaccines (a and b) and two VLP vaccines (c and d) for PCV2 from four manufacturers were analyzed by HPSEC-MALLS after demulsification. The antigen peaks in HPSEC-MALLS were identified by PCV2 antigen test strips, Western blotting and transmission electron microscope (TEM). The repeatability and linearity of the method were investigated. The results showed the virus antigens in the two inactivated vaccines were eluted at about 13.3 min in HPSEC. The molecular weight of these antigens was 2.61×10⁶ (±4.34%) Da and 2.40×10⁶ (±2.51%) Da, respectively, as calculated by MALLS. The antigen peaks of the two VLP vaccines also appeared at 13.3 min and the molecular weight was 2.09×10⁶ (±2.94%) Da and 2.88×10⁶ (±11.85%) Da, respectively, which was close to the theoretical molecular weight of PCV2. Moreover, an antigen peak of VLP vaccine c was observed at 11.4 min and the molecular weight was 4.37×10⁶ (±0.42%) Da. The antigen was verified to be the dimer of VLP by TEM. Vaccine d and purified Cap VLP antigens were tested repeatedly, and the RSD of the peak area (n=3) was all < 1.5%, indicating that the method was repeatable. The purified VLP were diluted in serial and tested for linearity. The result suggested good linear relationship between the peak area of VLP or VLP aggregates and the protein concentration of the sample with R² of 0.999 and 0.997, respectively. Thus, the method met the requirement for quantification and aggregate analysis. This method is accurate and efficient in in vitro quality evaluation and improvement of PCV2 vaccine.
Animals ; Antibodies, Viral ; Capsid Proteins ; Chromatography, Gel ; Circoviridae Infections/prevention & control* ; Circovirus ; Lasers ; Swine ; Vaccines, Inactivated ; Vaccines, Virus-Like Particle ; Viral Vaccines