Development and evaluation of an inactivated bivalent vaccine against duck viral hepatitis / 生物工程学报

The rapid mutation and widely spread of duck hepatitis A virus (DHAV) lead to the vast economic loss of the duck industry. To prepare and evaluate bivalent inactivated vaccine laboratory products of DHAV, 6 strains were screened from 201 DHAV-1 strains and 38 DHAV-3 strains by using serotype epidemiological analysis in most of the duck factory. Vaccine candidate strains were selected by ELD50 and LD50 tests in the 6 strains. Continuously passaged, the 5th passaged duck embryos bodies grinding fluid was selected as vaccine virus seeds. The virus seeds were treated with formaldehyde and water in oil in water (W/O/W) emulsions, making into three batches of two bivalent inactivated vaccine laboratory products. The safety test, antibody neutralization test, challenged protection and cross immune protection experiment suggested that the vaccines possessed good safety, and neutralizing antibodies were detected at 7th day and the challenged protection rate reached 90% to 100% at the 14th and 21st day. Moreover, immune duration of ducklings lasted more than five weeks. However, cross-immunity protection experiments with DHAV-SH and DHAV-FS only had 20%-30%. The two bivalent inactivated vaccine laboratory products of duck viral hepatitis were effective and reliable, providing a new method as well as a new product for DHAV prevention and control.

Diagnostic evaluation of the temporomandibular joint osteoarthritis using cone beam computed tomography compared with conventional radiographic technology / 北京大学学报(医学版)

Objective: Osteoarthritic lesions of Temporomandibular joint(TMJ) were assessed by dental cone beam computed tomography(CBCT),and compared with conventional radiographic technology. Methods: The study was conducted retrospectively on 511 joints of 350 patients, who had undergone dental CBCT ,panoramic radiography,transcranial projection and transpharygeal projection of TMJ . The results were compared and the accuracy with CBCT was assessed. The types of osseous condylar abnormalities were observed.Results: (1) The occurrence of osteoarthritis in male and female were 59.04% and 69.66%, respectively, with no significant difference. (2) Compared with CBCT, panoramic radiography,transpharygeal projection examination showed no significant difference, with the accuracy being 90.64% and 94.10%,respectively;However, transcranial projection indicated a significant difference in comparison with CBCT and the accuracy was 86.97%. (3) A higher occurrence of osteoarthritic lesions of the condyle was sclerosis (39.86%). Bony proliferation or osteophyte (28.18%) and ill-defined cortical bone (18.90%) were followed. Conclusion: Cone beam CT, which reproduces multiple images including axial, coronal and sagittal planes of the joint, provides a complete radiographic investigation of the bony components of the TMJ. It is one of the best choices of imaging diagnosis of TMJ osteoarthritis. Panoramic radiography and transpharygeal projection examination are also good choices for showing osseous condylar abnormalities in the clinic, but transcranial projection examination is inferior.

Investigation of temporomandibular joint space of healthy adults by using cone beam computed tomography / 北京大学学报(医学版)

0.05).Conclusion:All the results of the five measurement methods showed that the condyle was located in the center of the fossa with a variation in the healthy adults in intercuspal position.The CBCT image of the sagittal middle layer of the joint could show the joint space accurately and has an important value in the research related to the changes of TMJ space.