An adult gerbil model for evaluating potential coxsackievirus A16 vaccine candidates.

A suitable animal model of CVA16 infection is crucial in order to understand its pathogenesis and to help develop antiviral vaccines or screen therapeutic drugs. The neonatal mouse model has a short sensitivity period to CA16 infection, which is a major limitation. In this study, we demonstrate that adult (60-day-old) gerbils are susceptible to CVA16 infection at high doses (108.0 TCID50). A clinical isolate strain of CVA16 was inoculated intraperitoneally into adult gerbils, which subsequently developed significant clinical symptoms, including hind limb weakness, paralysis of one or both hind limbs, tremors, and eventual death from neurological disorders. Real-time RT-PCR revealed that viral loads in the spinal cord and brainstem were higher than those in other organs/tissues. Histopathological changes, such as neuronal degeneration, neuronal loss, and neuronophagia, were observed in the spinal cord, brainstem, and heart muscle, along with necrotizing myositis. Gerbils receiving both prime and boost immunizations of alum adjuvant inactivated vaccine exhibited no clinical signs of disease or mortality following challenge by CVA16, whereas 80% of control animals showed obvious clinical signs, including slowness, paralysis of one or both hind limbs, and eventual death, suggesting that the CVA16 vaccine can fully protect gerbils against CVA16 challenge. These results demonstrate that an adult gerbil model provides us with a useful tool for studying the pathogenesis and evaluating antiviral reagents of CVA16 infection. The development of this animal model would also be conducive to screening promising CVA16 vaccine candidates as well as further vaccination evaluation.

Maturity of associating liver partition and portal vein ligation for staged hepatectomy-derived liver regeneration in a rat model.

AIM: To establish a rat model for evaluating the maturity of liver regeneration derived from associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). METHODS: In the present study, ALPPS, partial hepatecotmy (PHx), and sham rat models were established initially, which were validated by significant increase of proliferative markers including Ki-67, proliferating cell nuclear antigen, and cyclin D1. In the setting of accelerated proliferation in volume at the second and fifth day after ALPPS, the characteristics of newborn hepatocytes, as well as specific markers of progenitor hepatic cell, were identified. Afterwards, the detection of liver function followed by cluster analysis of functional gene expression were performed to evaluate the maturity. RESULTS: Compared with PHx and sham groups, the proliferation of FLR was significantly higher in ALPPS group (P = 0.023 and 0.001 at second day, P = 0.034 and P < 0.001 at fifth day after stage I). Meanwhile, the increased expression of proliferative markers including Ki-67, proliferating cell nuclear antigen, and cyclin D1 verified the accelerated liver regeneration derived from ALPPS procedure. However, ALPPS-induced Sox9 positive hepatocytes significantly increased beyond the portal triad, which indicated the progenitor hepatic cell was potentially involved. And the characteristics of ALPPS-induced hepatocytes indicated the lower expression of hepatocyte nuclear factor 4 and anti-tryptase in early proliferative stage. Both suggested the immaturity of ALPPS-derived liver regeneration. Additionally, the detection of liver function and functional genes expression confirmed the immaturity of renascent hepatocytes derived in early stage of ALPPS-derived liver regeneration. CONCLUSION: Our study revealed the immaturity of ALPPS-derived proliferation in early regenerative response, which indicated that the volumetric assessment overestimated the functional proliferation. This could be convincing evidence that the stage II of ALPPS should be performed prudently in patients with marginally adequate FLR, as the ALPPS-derived proliferation in volume lags behind the functional regeneration.

Blunt Dissection: A Solution to Prevent Bile Duct Injury in Laparoscopic Cholecystectomy.

BACKGROUND: Laparoscopic cholecystectomy (LC) has been a standard operation and replaced the open cholecystectomy (OC) rapidly because the technique resulted in less pain, smaller incision, and faster recovery. This study was to evaluate the value of blunt dissection in preventing bile duct injury (BDI) in laparoscopic cholecystectomy (LC). METHODS: From 2003 to 2015, LC was performed on 21,497 patients, 7470 males and 14,027 females, age 50.3 years (14-84 years). The Calot's triangle was bluntly dissected and each duct in Calot's triangle was identified before transecting the cystic duct. RESULTS: Two hundred and thirty-nine patients (1.1%) were converted to open procedures. The postoperative hospital stay was 2.1 (0-158) days, and cases (46%) had hospitalization days of 1 day or less, and 92.8% had hospitalization days of 3 days or less; BDI was occurred in 20 cases (0.09%) including 6 cases of common BDI, 2 cases of common hepatic duct injury, 1 case of right hepatic duct injury, 1 case of accessory right hepatic duct, 1 case of aberrant BDI 1 case of biliary stricture, 1 case of biliary duct perforation, 3 cases of hemobilia, and 4 cases of bile leakage. CONCLUSION: Exposing Calot's triangle by blunt dissection in laparoscopic cholecystectomy could prevent intraoperative BDI.