ObjectiveTo establish a novel assay for HIV-1 p24 ultrasensitive detection based on Gold Nanoparticle Probe (GNP) and PCR.MethodsSandwich ELISA method was established by a pair of anti-p24 monoclonal antibodies (mAbs),1G12 and 1D4,and was used to detect recombinant HIV-1 p24 antigen.The bio-barcode DNA was 47 bp,selected from genome of Arabidopsis,and formed double-stranded DNA by hybridization with the capture DNA (complementary with bio-barcode DNA) modified with sulfhydryl.Then double-stranded DNA were conjugated on the surface of 1D4-modified gold nanoparticles by sulfhydryl,and the Gold Nanoparticle Probe was produced.1G12 was precoated in the micropaltes,and in the presence of target recombinant HIV-1 p24 protein,a sandwich immuno-complex would form by adding GNP.Then the bio-barcode DNA in the immuno-complex were released by heating as detection signal,and consequently characterized by the polymerase chain reaction (PCR) with synthesized special primers and analyzed by 4％ agar gel electrophoresis,so HIV-1 p24 antigen could be evaluated.The sensitivity comparison between the new assay and ELISA can be done.ResultsSandwich ELISA was used to quantify HIV-1 p24 antigen by monoclonal antibodies 1G12 and 1D4,and the limit of detection (LOD) was 1000 pg/ml.The new GNP assay was established by the same pair of antibodies,combined with PCR and agar gel electrophoresis,and was used to indirectly detect HIV-1 p24 antigen.The band intensity of PCR products paralleled with the quantity of HIV-1 p24 antigen,and the limit of detection (LOD) could reach down to 1 pg/ml.ConclusionThe new assay based on GNP and PCR was efficient in the detection of HIV-1 p24,which is at least 3 orders of magnitude more sensitive than traditional ELISA.

Objective:To explore the self-conscious health status and related influencing factors of greenhouse agricultural workers in Beijing suburb, so as to provide scientific basis for developing strategies to improve and promote the occupational health conditions of those workers.Methods:According to the production characteristics and scale of the main agricultural districts or counties in the suburb of Beijing, 182 agricultural production personnel were randomly selected to investigate the general situation, occupational situation and self-conscious health status during June 2018 to December 2019. The relevant factors which may affect the self-conscious health conditions were also analyzed by statistical methods.Results:The detection or reported rate of self-conscious health problems was 51.6% (94/182) , among which 29.1% (53/182) workers reported musculoskeletal disorder diseases and 21.4% (39/182) workers reported nervous system diseases. And the self-conscious health status of greenhouse agricultural workers were statistically different in household registration, gender, marital status, working years, mixing or spraying pesticides, smoking or eating in the greenhouse ( P<0.05) . Moreover, gender, mixing or spraying pesticide, eating and smoking behavior in the workplace all had an impact on the risk of self-conscious health status of greenhouse agricultural workers ( P< 0.05) . Specifically, male is the protective factor to reduce the occurrence of self-conscious symptoms of greenhouse agricultural workers ( OR=0.447, 95% CI: 0.234~0.852) , while mixing or spraying pesticides and smoking or eating behaviors in the workplace are the risk factors ( OR=1.055, 2.524; 95% CI: 0.503~2.210, 1.107~5.755) . Conclusion:Reducing pesticide use from the source thus minimize related exposure opportunities, strengthening occupational health education thus foster good hygienic habits and improve individual protection consciousness are of great significance for the health protection of greenhouse agricultural workers in Beijing suburb.

Objective:To explore the self-conscious health status and related influencing factors of greenhouse agricultural workers in Beijing suburb, so as to provide scientific basis for developing strategies to improve and promote the occupational health conditions of those workers.Methods:According to the production characteristics and scale of the main agricultural districts or counties in the suburb of Beijing, 182 agricultural production personnel were randomly selected to investigate the general situation, occupational situation and self-conscious health status during June 2018 to December 2019. The relevant factors which may affect the self-conscious health conditions were also analyzed by statistical methods.Results:The detection or reported rate of self-conscious health problems was 51.6% (94/182) , among which 29.1% (53/182) workers reported musculoskeletal disorder diseases and 21.4% (39/182) workers reported nervous system diseases. And the self-conscious health status of greenhouse agricultural workers were statistically different in household registration, gender, marital status, working years, mixing or spraying pesticides, smoking or eating in the greenhouse ( P<0.05) . Moreover, gender, mixing or spraying pesticide, eating and smoking behavior in the workplace all had an impact on the risk of self-conscious health status of greenhouse agricultural workers ( P< 0.05) . Specifically, male is the protective factor to reduce the occurrence of self-conscious symptoms of greenhouse agricultural workers ( OR=0.447, 95% CI: 0.234~0.852) , while mixing or spraying pesticides and smoking or eating behaviors in the workplace are the risk factors ( OR=1.055, 2.524; 95% CI: 0.503~2.210, 1.107~5.755) . Conclusion:Reducing pesticide use from the source thus minimize related exposure opportunities, strengthening occupational health education thus foster good hygienic habits and improve individual protection consciousness are of great significance for the health protection of greenhouse agricultural workers in Beijing suburb.