[ Objective ] To screen the duck model with congenital infection of duck hepatitis B virus (DHBV) by polymerase chain reaction (PCR) method. [Methods] Serum DHBV-DNA level in one-day-old ducklings was detected by PCR method and was compared with that by Dot-blot method. Ducklings with serum DHBV-DNA being negative confirmed by PCR method were inoculated DHBV-DNA positive serum to establish acquired infection models. Pathological features of liver tissues in the congenital infec tion model and the acquired infection model were also observed. [Results] Sensitivity and specificity of PCR detecting serum DHBV-DNA were superior to those of Dot-blot method. In the congenital infection model, viremia maintained long time, the titer of serum DHBV-DNA was high and the inflammatory af fection in liver tissues was slight as compared with those in the acquired infection model. [Conclusion] The duck model with congenital infection of DHBV screened by PCR method is more suitable for the phar macological and pharmacodynamic research of drugs for chronic hepatitis B.

Objective · To observe the micro-structure changes in rat tooth movement process under different force values through Micro-CT dynamic observation. Methods · Fifteen SD adult male rats at the age of 8 weeks were divided into three groups randomly (n=5), with the left maxillary as the experimental side and the nickel titanium coil springs, fixed between the first molar and incisor where thrust augmentation was conducted respectively by 20, 50 and 100 gf (1gf=0.0098 N) for continuous 14 d to it. Rat scanning in vivo through Micro-CT was carried out at day 0, 3, 7, 10 and 14 after force values were loaded on. The root resorption crater volumes and structure parameters for bone trabecula at different time points were measured. Results · Three days after thrust augmentation was conducted, root resorption crater volume for each group had a slight increase and an obvious increase occurred from the 3rd day to the 10th day, and then a slow increase happened 10 d later; from the 7th day to the 14th day, root resorption crater volume for 100 gf stress group was obviously greater than those of the other groups with statistical differences (P<0.05). With time for thrust augmentation passing by, bone volume fraction at the pressure side of alveolar bone decreased gradually and bone trabecula morphology became tiny and exiguous; besides, bone trabecula gap became narrow first and broad afterwards, and trabeculae trended to change from clintheriform to rhabditiform. Furthermore, alveolar bone resorption occurred in each stress group with consistent tendency. Conclusion · Different orthodontic force values all can cause root resorption, which experiences lag phase, rapid phase and stationary phase. Over-loaded orthodontic force induces more root resorption. During the process of the tooth movement, the pressure side of alveolar bones appears reconstruction and absorption, whose variation is not related with force degree.

Objective To evaluate the pre- and intra-operative risk factors associated with delayed weaning from ventilator during the early postoperative period in patients undergoing liver transplantation.Methods Two hundred and twelve patients (152 male, 60 female) aged 22-69 yr undergoing liver transplantation from Sept 2004to Aug 2006 were enrolled in this study and were divided into 2 groups according to the time when the patients were weaned from ventilator: normal weaning group (Group A, the patients weaned from ventilator within 24 h after operation) and delayed weaning group (Group B, the patients weaned from ventilator more than 24 h after operation). Routine anesthesia wes performed. Blood and blood products were transfused according to the guidelines for blood transfusion to maintain the mean arterial pressure (MAP)≥60 mm Hg during operation. Sixteen preoperative variables (age＞64 yr, gender, BMI ≥ 30kg/m2, PaO2＜75 mm Hg,pleural effusion, a history of asthma, smoking, drinking alcohol, coronary artery disease, diabetes mellitus, encephalopathy＞grade 3, spontaneous bacterial peritonitis, preoperative MELD score, serum albumin, ascites≥20 ml/kg and moderate hepatopulmonary hypertension) and 7 intraoperative variables (duration of operation, duration of anhepatic stage, transfusions of RBC,fresh frozen plasma (FFP), crystalloid and colloid, and urine output＜ 1 ml·kg-1·h-1) were recorded and compared between the two groups.Results There were significant differences in 9 preoperative variables (age ＞ 64 yr, PaO2＜75 mm Hg, pleural effusion,encephalopathy＞grade 3, spontaneous bacterial peritonitis, preoperative MELD score, serum albumin, ascites≥20 ml/kg and moderate hepato-pulmonary hypertension) and 5 intraoperative variables (transfusions of RBC, FFP, crystalloid and colloid, and urine output＜1 mi·kg-1·h-1) between the two groups (P＜0.05 or 0.01). And logistic regression analysis showed that 5preoperative variables (age＞64 yr, PaO2＜75 mm Hg, encephalopathy ＞ grade 3, preoperative MELD score, and moderate hepato-pulmonary hypertension) and 2 intraoperative variables (transfusion of RBC and urine output＜1 ml·kg-1·h-1) were confirmed to be associated with delayed weaning from ventilator.Conclusion Such variables es age ＞ 64 yr, preoperative PaO2 ＜ 75 mm Hg, encephalopathy ＞ grade 3, preoperative MELD score, moderate hepato-pulmonary hypertension, transfusion of RBC during operation and urine output ＜ 1 ml· kg-1 · h-1 are associated with delayed weaning from ventilator during early postoperative period after liver transplantation.

Objective To explore the current status of posttraumatic growth (PTG) among nurses at psychiatric department and analyze its latent profiles and population characteristics. Methods A total of 357 nurses from psychiatric departments of five tertiary Grade A hospitals were selected as the research subjects using the convenience sampling method. The PTG and professional quality of life were studied using the Posttraumatic Growth Inventory and the Chinese version of the Compassion Fatigue Scale. Results The PTG score of the nurses was (56.6±23.2). The scores of compassion satisfaction, burnout, and secondary traumatic stress among nurses were (32.6±7.2), (26.9±5.9), and (26.0±5.4), respectively. The result of potential profile analysis showed that the nurses could be divided into three latent profiles based on PTG levels: low PTG group (34.4%), moderate PTG group (44.0%), and high PTG group (21.6%). The results of multinomial logistic regression analysis showed that the nurses who slept 7-8 hours per day were at higher risk of being in the high PTG group compared with those who slept more than eight hours per day (P<0.05). Psychiatric nurses who took regular exercise were at higher risk of being in the high PTG group compared with those who took irregular exercise (P<0.05). The nurses who had high job satisfaction scores were at higher risk of being in the high PTG group compared with those who had low job satisfaction scores (P<0.01). The nurses with higher compassion satisfaction scores increased the risk of being in the high PTG group compared with those with lower compassion satisfaction scores (P<0.01). The nurses with higher burnout scores increased the risk of being in the low PTG group compared with those with lower burnout scores (P<0.01). Conclusion The PTG characteristics of the nurses exhibit heterogeneity and can be categorized into three distinct profiles. Sleep duration, regular exercise, job satisfaction, compassion satisfaction, and burnout are influencing factors for the PTG latent profiles of nurses working at psychiatric department.

Consolidated bioprocessing (CBP) is a multi-step process in a bioreactor, which completes hydrolase production, enzymatic hydrolysis, and microbial fermentation. It is considered to be the most promising process for the production of second-generation biofuels because of its simple steps and low cost. Due to the complexity of lignocellulose degradation and the butanol synthesis pathway, few wild microorganisms can directly utilize lignocellulose to synthesize butanol. With the development of synthetic biology, single-bacterium directly synthesizes butanol using lignocellulose by introducing a butanol synthesis pathway in the cellulolytic Clostridium. However, there are still some problems such as heavy metabolic load of single bacterium and low butanol yield. Co-culture can relieve the metabolic burden of single bacterium through the division of labor in different strains and can further improve the efficiency of butanol synthesis. This review analyzes the recent research progress in the synthesis of biobutanol using lignocellulose by consolidated bioprocessing from both the single-bacterium strategy and co-culture strategy, to provide a reference for the research of butanol and other biofuels.
1-Butanol ; Biofuels ; Butanols ; Fermentation ; Lignin/metabolism*