We analyzed genetic evolution characteristics of avian influenza A (H7N9) virus isolated in Zhaoqing,China,2014-2016.Nucleic acid were extracted and sequenced from 17 samples of H7N9 positive cases in Zhaoqing.Genetic characteristics of homology and important amino acid sites were analyzed by using BioEdit5.0 and MEGA6.0.The evolutionary trees were constructed by Neighbor-Joining and the referenced sequences were downloaded from GenBank,Eight nucleic acid fragments from 7 strains of H7N9 viruses were successfully generated.The highest homology was found in HA gene with A/chicken/Dongguan/695/2014(H7N9),and NA gene with A/chicken/Dongguan/1075/2014(H7N9).The internal genes were high homology with avian H7N9 and H9N2 virus from Dongguan and Shenzhen in Guangdong,China.The HA and NA genes were directly evolved in the Pearl River Delta evolution branch with the H7N9 sequences from the cities of Dongguan,Guangzhou and Shenzhen,while the sequences from the provinces of Anhui,Zhejiang,and Jiangsu were in the Yangtze River Delta evolution branch.There were 2 alkaline amino acids in cleavage site of HA,2 mutations (G186V and Q226L) in the crucial sites related with the receptor of HA protein,1 mutation (E627K) in PB2 protein,and 1 drug resistance mutation (S31N) in M2 protein.And no evidence of neuraminidase resistance in NA protein was found.In conclusion,the H7N9 virus for human infection in Zhaoqing may originate from avian H7N9 and H9N2 viruses,which circulated in the Pearl River Delta region of Guangdong from 2013 to 2014.The mutations of G186V,Q226L and E627 K might be related with high susceptibility to human beings.

Objective To make up the limitations of traditional morphological classification methods,we identified vector fleas by DNA barcoding in Qinghai Province.Methods The mt DNA cytochrome c oxidase subunit Ⅰ (CO Ⅰ) gene was amplified by PCR from 36 muscle tissues of fleas in 3 states,2 cities and 5 counties of Qinghai Province,and the obtained CO Ⅰ gene fragments were sequenced and aligned.The intra-and inter-species genetic distances were calculated with Mega 6 software using K2-P model and a phylogenetic tree was constructed with neighbor-joining (NJ) method.Results Totally 36 CO Ⅰ gene sequences of 2 superfamilies,4 genera and 6 kinds of vector fleas were measured,the average genetic distance was 0.119,and the intraspecific distance was 0.002-0.027,the interspecific distance was 0.039-0.207,and the interspecific genetic distance was significantly greater than the intraspecific genetic distance.NJ tree showed the same species had formed a single line with high support rate and interspecific branch was clear.Conclusion DNA barcoding is suitable for identification of vector fleas in Qinghai Province,may make up the limitations of traditional morphological classification methods.

Purpose: This study was performed to analyze the rule of confluence of the caudate lobe bile duct (CLD) into the left hepatic duct (LHD) and to discuss the protective strategy during left hemihepatectomy. Methods: MRI of 400 patients and T-tube angiography images of 100 patients were collected, and the imaging rules of the confluence of the CLD into the LHD were summarized. The clinical data of 33 patients who underwent left hemihepatectomy using the protective strategy were analyzed. Results: MRI and T-tube angiography images showed that the length from the confluence point of the CLD into the LHD to the confluence of the left and right hepatic ducts was 1.19 ± 0.40 cm and 1.26 ± 0.39 cm, respectively. The average angle between the longitudinal axis of the 2 bile ducts was 68.27° ± 22.59° and 66.58 ± 22.88°, respectively. Coronal and cross-sectional images showed that inflow from the foot side to the cranial side was noted in 79.8% and 82.0% of patients, respectively, and inflow from the dorsal to the ventral side was observed in 84.5% and 88.0%, respectively. Based on these imaging rules, the safe transection length and plane were summarized, and the CLD was effectively protected in 33 cases of left hemihepatectomy. Conclusion In left hemihepatectomy, the LHD should be transected at least 1.5 cm away from the confluence of the left and right hepatic ducts, and the plane of transection should be oblique to the dorsal side at an angle of 45° with the LHD, these parameters represent an effective strategy to protect the CLD.

Background: Hydrogen bonding interaction was considered to play a critical role in controlling drug release from transdermal patch. However, the quantitative evaluation of hydrogen bonding strength between drug and polar functional group was rarely reported, and the relationship between hydrogen bonding strength and controlled release capacity of pressure sensitive adhesive (PSA) was not well understood. The present study shed light on this relationship. Methods: Acrylate PSAs with amide group were synthesized by a free radical-initiated solution polymerization. Six drugs, , etodolac, ketoprofen, gemfibrozil, zolmitriptan, propranolol and lidocaine, were selected as model drugs. drug release and skin permeation experiments and pharmacokinetic experiment were performed. Partial correlation analysis, fourier-transform infrared spectroscopy and molecular simulation were conducted to provide molecular details of drug-PSA interactions. Mechanical test, rheology study, and modulated differential scanning calorimetry study were performed to scrutinize the free volume and molecular mobility of PSAs. Results: Release rate of all six drugs from amide PSAs decreased with the increase of amide group concentrations; however, only zolmitriptan and propranolol showed decreased skin permeation rate. It was found that drug release was controlled by amide group through hydrogen bonding, and controlled release extent was positively correlated with hydrogen bonding strength. Conclusion From these results, we concluded that drugs with strong hydrogen bond forming ability and high skin permeation were suitable to use amide PSAs to regulate their release rate from patch.

Objective    To evaluate the safety and efficacy of mitral valve surgery and cryoablation in elderly patients with mitral valve disease and persistent or long-term persistent atrial fibrillation. Methods    From May 2014 to July 2018, 144 patients with mitral valve diseases combined with persistent or long-term persistent atrial fibrillation in the Department of Cardiothoracic Surgery, General Hospital of Northern Theater Command were selected. Among them, there were 69 patients in a non-elderly group (<60 years) including 18 males and 51 females aged 52.07±5.56 years, and 75 patients in an elderly group (≥60 years) including 32 males and 43 females aged 65.23±4.29 years. A propensity-score matching (PSM) study was conducted to eliminate confounding factors. Both groups underwent mitral valve surgery and cryoablation at the same time. A 2-year follow-up was conducted after discharge from the hospital, and the perioperative and postoperative efficacy indexes were compared between the two groups. Results    After PSM analysis, there were 56 patients in each group. The sinus rhythm conversion rate of the two groups at each follow-up time point was above 85%, and the cardiac function was graded asⅠorⅡ, which was significantly improved compared with that before the surgery, but there was no statistical difference between the two groups (P>0.05). Among the perioperative indicators of the two groups, the elderly group had more coronary artery bypass graft surgeries and longer postoperative ICU stay time compared with the non-elderly group (P<0.05), and the differences in other indicators were not statistically different (P>0.05). Conclusion    The mitral valve surgery and cryoablation in elderly patients with mitral valve diseases combined with persistent or long-term persistent atrial fibrillation are safe, and the short-term outcome is satisfactory.

Objective To evaluate the incidence of postoperative atrial fibrillation (POAF) after dexmedetomidine and diazepam in patients undergoing coronary artery bypass grafting (CABG). Methods A retrospective cohort study was conducted in the patients who underwent CABG in the General Hospital of Northern Theater Command from October 2020 to June 2021. By propensity score-matching method, the incidence of POAF after dexmedetomidine and diazepam application in patients undergoing CABG was evaluated. Results Finally 207 patients were collected, including 150 males and 57 females, with an average age of 62.02±8.38 years. Among the 207 patients, 53 were treated with dexmedetomidine and 154 with diazepam before operation. There was a statistical difference in the proportion of hypertension patients and smoking patients between the two groups before matching (P<0.05). According to the 1∶1 propensity score-matching method, there were 53 patients in each of the two groups, with no statistical difference between the two groups after matching. After matching, the incidence of POAF in the dexmedetomidine group was lower than that in the diazepam group [9.43% (5/53) vs. 30.19% (16/53), P=0.007]. There was no death in the two groups during hospitalization, and there was no statistical difference in the main adverse events after operation. The ICU stay (21.28±2.69 h vs. 22.80±2.56 h, P=0.004) and mechanical ventilation time (18.53±2.25 h vs. 19.85±2.01 h, P=0.002) in the dexmedetomidine group were shorter. Regression analysis showed that age, smoking and diabetes were related to the increased incidence of POAF (P<0.05), and preoperative use of dexmedetomidine was associated with a reduced incidence of POAF (P=0.002). Conclusion For patients undergoing CABG, the incidence of POAF with dexmedetomidine before operation is lower than that with diazepam. Preoperative application of dexmedetomidine is the protective factor for POAF, and old age, smoking and diabetes are the risk factors for POAF.

Objective To investigate the safety and efficacy of mitral valve replacement combined with cryoablation Maze surgery in patients with atrial functional mitral regurgitation (AFMR). Methods From January 2014 to June 2020, patients with AFMR who underwent mitral valve replacement in our department were enrolled. They were divided into two groups, a cryoablation Maze group who received cryoablation Maze surgery during mitral valve replacement, and a non-cryoablation Maze group who did not receive cryoablation Maze surgery. The baseline data, surgical data, efficacy, and prognosis between the two groups were compared. Results Finally 85 patients were enrolled. There were 16 males and 24 females with an average age of 58.65±6.86 years in the cryoablation Maze group, and 24 males and 21 females with an average age of 61.29±8.30 years in the non-cryoablation Maze group. There was no statistical difference in baseline data between the two groups (P＞0.05). The aortic occlusion time and extracorporeal circulation time of the cryoablation Maze group were longer than those of the non-cryoablation Maze group with statistical differences (P＜0.01). There was no statistical difference in postoperative ICU retention time, ventilator assistance time, length of hospital stay, intraoperative blood loss, drainage volume on the first day or occurrence rate of complications (temporary pacemaker application, electrical cardioversion, thoracic puncture drainage, hospitalization death) between the two groups (P＞0.05). At the time of discharge, postoperative 3-month, 6-month, 12-month, and 24-month, the maintenance rates of sinus rhythm in the non-cryoablation Maze group were statistically different from those of the cryoablation Maze group (P＜0.001). Compared with the non-cryoablation Maze group, the decrease values of left atrial diameter, left ventricular end-diastolic diameter, left ventricular end-systolic diameter and pulmonary artery systolic pressure were statistically different (P＜0.05). Postoperative cardiac function grading of both groups was grade Ⅰ or Ⅱ, which was significantly improved compared with preoperative level, but there was no statistical significance between the two groups (P＞0.05). There was no statistical difference in the incidence of adverse events during follow-up (P＞0.05). Conclusion Cryoablation Maze surgery combined with mitral valve replacement is safe and effective in the treatment of AFMR patients, which is conducive to the recovery and maintenance of sinus rhythm, and is beneficial to the remodeling of the left atrium and left ventricle, the reduction of pulmonary systolic blood pressure, and the improvement of life quality of the patients.