A chimeric dengue virus vaccine using Japanese encephalitis virus vaccine strain SA14-14-2 as backbone is immunogenic and protective against either parental virus in mice and nonhuman primates.

The development of a safe and efficient dengue vaccine represents a global challenge in public health. Chimeric dengue viruses (DENV) based on an attenuated flavivirus have been well developed as vaccine candidates by using reverse genetics. In this study, based on the full-length infectious cDNA clone of the well-known Japanese encephalitis virus live vaccine strain SA14-14-2 as a backbone, a novel chimeric dengue virus (named ChinDENV) was rationally designed and constructed by replacement with the premembrane and envelope genes of dengue 2 virus. The recovered chimeric virus showed growth and plaque properties similar to those of the parental DENV in mammalian and mosquito cells. ChinDENV was highly attenuated in mice, and no viremia was induced in rhesus monkeys upon subcutaneous inoculation. ChinDENV retained its genetic stability and attenuation phenotype after serial 15 passages in cultured cells. A single immunization with various doses of ChinDENV elicited strong neutralizing antibodies in a dose-dependent manner. When vaccinated monkeys were challenged with wild-type DENV, all animals except one that received the lower dose were protected against the development of viremia. Furthermore, immunization with ChinDENV conferred efficient cross protection against lethal JEV challenge in mice in association with robust cellular immunity induced by the replicating nonstructural proteins. Taken together, the results of this preclinical study well demonstrate the great potential of ChinDENV for further development as a dengue vaccine candidate, and this kind of chimeric flavivirus based on JE vaccine virus represents a powerful tool to deliver foreign antigens.

Biomechanical finite element analysis of various tibial plateau posterior tilt angles in medial unicondylar knee arthroplasty.

The present study aimed to determine the optimal posterior tibial plateau inclination for fixed-platform unicondylar knee arthroplasty (UKA) using finite element analysis (FEA). These findings provided a theoretical basis for selecting an appropriate posterior inclination of the tibial plateau during surgery. The present study utilized the FEA method to create models of fixed-platform UKA with tibial plateau posterior inclinations of 3, 6 and 9˚. The stress changes in the internal structures of each model after knee flexion motion were then compared. During knee flexion from 0 to 90˚, the contact and Von Mises equivalent stresses of the femoral condyle prosthesis and tibial platform pad revealed consistent trends of 3˚ posterior inclination, >6˚ posterior inclination and >9˚ posterior inclination. The present study established the first quasi-dynamic fixed-platform UKA model of the knee joint under load-bearing conditions. From a theoretical perspective, it was found that controlling the posterior inclination of UKA between 6 and 9˚ may be more beneficial for the survival of the tibial platform pad than between 3 and 6˚. It is also more effective in reducing pad wear.

The Value of Susceptibility-Weighted Imaging (SWI) in Evaluating the Ischemic Penumbra of Patients with Acute Cerebral Ischemic Stroke.

BACKGROUND: The aim of this study was to discuss the value of susceptibility-weighted imaging (SWI) in evaluating the ischemic penumbra of patients with acute cerebral ischemic stroke. METHODS: Data were collected from 52 patients with acute cerebral ischemic stroke upon clinical diagnosis and routine examinations of magnetic resonance imaging (MRI), including SWI, diffusion-weighted imaging (DWI), and perfusion-weighted imaging (PWI) within 72 hours after onset in this retrospective study. The methods also included fusing the DWI and SWI images and calculating the volume of anomaly extension of DWI and PWI-MTT (mean transit time) using semi-automatic analysis software. The SWI-DWI and PWI-DWI mismatches were interpreted, and the statistical analysis was completed. RESULTS: The two physicians found that the ischemic penumbra consistency is high throughout the SWI-DWI and PWI-DWI mismatches, without a significant difference (P > 0.05). CONCLUSION: SWI-DWI mismatch can prevent the injection of contrast agents and make an accurate diagnosis of acute stroke ischemic penumbra, which helps guide the selection of the clinical therapeutic plan.

[Heel deep tissue defects were repaired by perineal tendofascial flap conjoined with adipofascial flap].

OBJECTIVE: To explore a new method and estimate its outcome to repair deep heel tissue injuries with local tissue flap. METHODS: At lower cnemis, a fat fascial flap combined with perineal tendofascial flap were designed and elevated between the lateral malleolars blank, the largest area is 6 cm x 13 cm, which were transplanted to cover naked calcaneal tendon and calcaneal bone, full-thickness free skin graft or middle-thickness free skin graft were grafted on flap. RESULTS: 6 patients suffered from heel tissue defects had been treated from January 2004 to November 2005. The smallest area was 3.5 cm x 4.0 cm and the largest was 4 cm x 6 cm. All fascial flaps and free skin grafts were successfully survived after operations. All patients were followed up 3-23 months, the operation areas were healed, the functions and configurations were satisfied. CONCLUSIONS: Perineal tendofascial flap conjoined with adipofasical flap and free skin graft are used to repair heel deep tissue defects, which is a handy, dependable way for repairing of the small tissue defects of the lower third of leg and heel.