Protection of chickens against hepatitis-hydropericardium syndrome and Newcastle disease with a recombinant Newcastle disease virus vaccine expressing the fowl adenovirus serotype 4 fiber-2 protein.

Newcastle disease (ND) is one of the most important and devastating avian diseases with considerable threat to the global poultry industry. Hepatitis-hydropericardium syndrome (HHS), caused by virulent fowl adenovirus serotype 4 (FAdV-4), is another highly infectious disease in chickens with severe economic impact. The effective way to combat ND and HHS is by vaccinating the poultry. In the present study, a recombinant NDV LaSota vaccine strain expressing full length fiber-2 gene of FAdV-4 (rLaSota-fiber2) was generated using reverse genetics. The FAdV-4 fiber-2 protein was expressed as a soluble form rather than NDV membrane-anchored form. The rLaSota-fiber2 was genetically stable, and it showed growth patterns in embryonated eggs comparable to that of parental rLaSota virus. Since our unpublished data demonstrated that delivery of live rLaSota-fiber2 in drinking water or ocular delivery of the vaccine didn't produce protection against hypervirulent FAdV-4 challenge, even though the vaccine provide full protection against NDV challenge, the efficacy of the rLaSota-fiber2 was evaluated by delivering the vaccine intramuscularly in this study. Single-dose intramuscular vaccination of 2-week-old SPF White Leghorn chicks with the live or inactivated rLaSota-fiber2 provided complete protection against virulent NDV challenge. However, single-dose intramuscular vaccination with the live rLaSota-fiber2 vaccine provided better protection against virulent FAdV-4 challenge and significantly reduced faecal viral shedding comparing to the inactivated vaccine. These results indicate that the NDV-vectored FAdV-4 vaccine is a promising bivalent vaccine candidate to control both HHS and ND.

Development of a reverse transcription recombinase polymerase amplification combined with lateral-flow dipstick assay for avian influenza H9N2 HA gene detection.

H9N2 avian influenza viruses (AIVs) have been detected from wild birds and domestic poultry worldwide. Serious diseases combined with secondary infection have caused high mortality and great economic losses to poultry industry. Therefore, simple, rapid, sensitive and accurate methods suitable for field detection of H9N2 AIVs are crucial to efficiently control virus infection and spread in time. In this study, an isothermal reverse transcription recombinase polymerase amplification with lateral-flow dipstick (RT-RPA-LFD) assay for detection of hemagglutinin (HA) gene of H9 subtype influenza viruses was developed. The optimal forward and reverse primers targeting HA gene of H9 subtype influenza viruses were labeled with fluorescein isothiocyanate (FITC) and biotin at the 5'-end, respectively. The amplification reaction could be finished in 20 min at a wide temperature range of 30-42°C, and then the products could be visualized with naked eyes. The developed H9 RT-RPA-LFD was able to detect 0.15 pg of H9N2 AIV RNA, which was 10 times more sensitive than that of conventional RT-PCR. The H9 RT-RPA-LFD assay did not detect nucleic acids extracted from H9 negative samples or from other poultry respiratory pathogens. The clinical performance of H9 RT-RPA-LFD was determined by testing 120 cloacal samples collected from chickens with respiratory syndromes. The coincidence rate of the detection results between RT-RPA-LFD and conventional RT-PCR was 95.8%. Therefore, the developed RT-RPA-LFD assay provides a rapid, reliable and sensitive method for field diagnosis of H9 subtype AIVs.

Modified method of recording and reproducing natural head position with a multicamera system and a laser level.

INTRODUCTION: As computer-assisted surgical design becomes increasingly popular in maxillofacial surgery, recording patients' natural head position (NHP) and reproducing it in the virtual environment are vital for preoperative design and postoperative evaluation. Our objective was to test the repeatability and accuracy of recording NHP using a multicamera system and a laser level. METHODS: A laser level was used to project a horizontal reference line on a physical model, and a 3-dimensional image was obtained using a multicamera system. In surgical simulation software, the recorded NHP was reproduced in the virtual head position by registering the coordinate axes with the horizontal reference on both the frontal and lateral views. The repeatability and accuracy of the method were assessed using a gyroscopic procedure as the gold standard. RESULTS: The interclass correlation coefficients for pitch and roll were 0.982 (0.966, 0.991) and 0.995 (0.992, 0.998), respectively, indicating a high degree of repeatability. Regarding accuracy, the lack of agreement in orientation between the new method and the gold standard was within the ranges for pitch (-0.69°, 1.71°) and for roll (-0.92°, 1.20°); these have no clinical significance. CONCLUSIONS: This method of recording and reproducing NHP with a multicamera system and a laser level is repeatable, accurate, and clinically feasible.

[Establishment and accuracy examination of gyroscope for recording and transferring natural head position].

OBJECTIVE: To build up and validate a system based on gyroscope to record human natural head position (NHP) and to transfer it into virtual surgical design system. METHODS: Three dimensional (3D) mechanical gyroscope and 3D design software were integrated in the system. The protocol for recording and transforming NHP included four steps. Firstly, the gyroscope was CT scanned when its position was (0, 0, 0), a virtual model was built up by 3D reconstruction and considered as standard gyroscope model. Secondly, the gyroscope was bounded to the patient's head using bite-jid and face bow. The NHP was recorded when the patient was looking himself into mirror. Thirdly, the virtual head of the patient was overlapped with standard gyroscope model. Finally, when pitch, roll and yaw of NHP were applied to the compound model, the virtual head was orientated to NHP. A standard cube model was used to validate the accuracy of the system. The cube was positioned 30 times, the real and virtual pitch, roll and yaw angles were recorded. The accuracy of the system was presented by the mean ± SD of the Delta. the difference between the real and virtual pitch, roll and yaw angles were analyzed by paired t test,and their correlations were investigated by Pearson test. RESULTS: The accuracy rates of the system were ΔPitch = 0.03 ± 0.28°,ΔRoll = 0.03 ± 0.23°,ΔYaw = 0.07 ± 0.49°. There were no significant differences between the real and virtual pitch, roll and yaw angles (P > 0.05). The two positions were absolutely correlated at the level of α = 0.01 (2-tailed, r = 1.00). CONCLUSION: The method of recording and transforming NHP using gyroscope is clinically applicable. The accuracy of transferring system meets the needs of virtual surgical design.

[Clinical application of condylectomy via intraoral approach under computer assisted surgical navigation].

OBJECTIVE: To assess the application of computer assisted surgical navigation in condylectomy via intraoral approach and its clinical results. METHODS: Eight patients aged from 16 to 56 were treated by condylectomy via intraoral approach under computer assisted surgical navigation. There were 6 female and 2 male. The lesions were condyle osteoma in 3 patients, hemimandibular hyperplasia and condylar hyperplasia in 5 patients. Most patients had concomitant LeFortIosteotomy (6 cases), bilateral sagittal split ramus osteotomy (BSSRO) (5 cases),contralateral sagittal split ramus osteotomy (SSRO) (1 cases), genioplasty (4 cases) and mandible contouring (6 cases) to recover the facial symmetry. RESULTS: All patients had good occlusion, oral function and facial symmetry after the operation. The average mouth opening was 38 mm before operation, and 41 mm one month after operation. The temporomandibular joint(TMJ) dysfunction syndrome alleviated or disappeared. The follow-up period was 3-12 months, and results were stable. CONCLUSIONS: Computer assisted surgical navigation can precisely accomplish the condylectomy via intraoral approach.It causes less trauma to the patient than traditional condylectomy, and can better preserve the TMJ structure and function.