Objective:To investigate the pollution levels and influencing factors of polybrominated diphenyl ethers (PBDEs) in household dust in five cities in northern China.Methods:Based on the "Chinese Indoor Environment and Health Surveillance" project carried out by the National Institute of Environmental Health, Chinese Center for Disease Control and Prevention in 2018-2019, during the warm season (April 2018 to September 2018) and the cold season (November 2018 to March 2019), Lanzhou in Northwest China, Shijiazhuang in North China, Panjin in Northeast China, Luoyang in Central China, and Qingdao in East China were selected as the research sites. A total of 87 families were recruited to study residences in real-life scenarios. At the same time, dust samples were collected to detect the concentration of PBDEs. The level of household environmental indicators was measured, and the residential building characteristics and family behavior habits were collected through questionnaires. A total of 142 valid dust samples and 140 valid questionnaires were obtained. The differences in PBDE concentrations across seasons, wind zones, residential building characteristics, and family habits were analyzed. The exploratory factor analysis was performed to investigate the possible sources of PBDEs, and multivariate linear regression was used to explore the factors influencing PBDEs in household dust.Results:The M ( Q1,Q3) of total PBDE concentrations in 142 household dust samples in five cities was 144.51 (106.61, 222.65) ng/g in the warm season and 145.10 (98.57, 180.65) ng/g in the cold season, respectively. There were seasonal differences in the concentration of ∑ 12PBDEs in Luoyang and Shijiazhuang ( P<0.01). The concentration of BDE-71 was highest among PBDE homologues, followed by BDE-66 and BDE-47. Three factors were extracted by exploratory factor analysis in the warm season, and the cumulative variance contribution rate was 67.90%. The multivariate linear regression showed that the house completion less than ten years [ β (95% CI): 0.186 (0.013, 0.359)], infrequent home cooking [ β (95% CI):-0.342 (-0.570, -0.114)], and increased residential PM 10 concentration [ β (95% CI): 0.001 (0.000, 0.002)] during the warm season, as well as the house far from driveway [ β (95% CI): 0.093 (0.013, 0.172)], house area less than 90 m 2 [ β (95% CI):-0.138 (-0.264, -0.013)], and lower residential xylene concentration [ β (95% CI):-0.006 (-0.011, -0.001)] during the cold season might be related to the elevated concentrations of ∑ 12PBDEs in household dust. Conclusion:The pollution of PBDEs in household dust in five northern cities is at a medium to high level. Years of house completion, frequency of cooking at home, residential PM 10 concentration, distance from house to driveway, house area, and residential xylene concentration may influence household PBDE concentrations.

Objective:To investigate the pollution levels and influencing factors of polybrominated diphenyl ethers (PBDEs) in household dust in five cities in northern China.Methods:Based on the "Chinese Indoor Environment and Health Surveillance" project carried out by the National Institute of Environmental Health, Chinese Center for Disease Control and Prevention in 2018-2019, during the warm season (April 2018 to September 2018) and the cold season (November 2018 to March 2019), Lanzhou in Northwest China, Shijiazhuang in North China, Panjin in Northeast China, Luoyang in Central China, and Qingdao in East China were selected as the research sites. A total of 87 families were recruited to study residences in real-life scenarios. At the same time, dust samples were collected to detect the concentration of PBDEs. The level of household environmental indicators was measured, and the residential building characteristics and family behavior habits were collected through questionnaires. A total of 142 valid dust samples and 140 valid questionnaires were obtained. The differences in PBDE concentrations across seasons, wind zones, residential building characteristics, and family habits were analyzed. The exploratory factor analysis was performed to investigate the possible sources of PBDEs, and multivariate linear regression was used to explore the factors influencing PBDEs in household dust.Results:The M ( Q1,Q3) of total PBDE concentrations in 142 household dust samples in five cities was 144.51 (106.61, 222.65) ng/g in the warm season and 145.10 (98.57, 180.65) ng/g in the cold season, respectively. There were seasonal differences in the concentration of ∑ 12PBDEs in Luoyang and Shijiazhuang ( P<0.01). The concentration of BDE-71 was highest among PBDE homologues, followed by BDE-66 and BDE-47. Three factors were extracted by exploratory factor analysis in the warm season, and the cumulative variance contribution rate was 67.90%. The multivariate linear regression showed that the house completion less than ten years [ β (95% CI): 0.186 (0.013, 0.359)], infrequent home cooking [ β (95% CI):-0.342 (-0.570, -0.114)], and increased residential PM 10 concentration [ β (95% CI): 0.001 (0.000, 0.002)] during the warm season, as well as the house far from driveway [ β (95% CI): 0.093 (0.013, 0.172)], house area less than 90 m 2 [ β (95% CI):-0.138 (-0.264, -0.013)], and lower residential xylene concentration [ β (95% CI):-0.006 (-0.011, -0.001)] during the cold season might be related to the elevated concentrations of ∑ 12PBDEs in household dust. Conclusion:The pollution of PBDEs in household dust in five northern cities is at a medium to high level. Years of house completion, frequency of cooking at home, residential PM 10 concentration, distance from house to driveway, house area, and residential xylene concentration may influence household PBDE concentrations.

Objective:To evaluate the perioperative safety and long-term prognosis of allogeneic vein replacement in abdominal surgery.Methods:Clinical data of 115 patients receiving allogeneic vein replacement from Jan 2013 to Dec 2020 was retrospectively analyzed.Results:The most common operation was radical pancreatoduodenectomy for pancreatic cancer (75.7%), and the most common vascular replacement sites were the junction of portal vein system (53.9%), followed by superior mesenteric vein (23.5%) and portal vein (18.3%). In our group, 6 patients died (5.2%), 31 patients had complications (27.0%), and 2 patients had portal vein thrombosis (1.7%). During the follow-up period, 8 cases (7.5%) had mild stenosis, 12 cases (11.5%) had moderate stenosis and 14 cases (13.2%) had severe stenosis. The half-year, one-year and two-year incidence of moderate and severe stenosis were 8.0%, 24.4% and 34.5% respectively.Conclusions:The early and mid-term result of allogeneic vein replacement is satisfactory. Use of postoperative anticoagulation may help reduce the incidence of thrombogenesis or stenosis .

Objective:To evaluate the effect of allogenic vein replacement in treatment of borderline resectable pancreatic cancer, and to analyze risk factors of long-term stenosis.Methods:The clinical data of 77 patients with borderline resectable pancreatic cancer who underwent surgery from January 2013 to December 2021 at the Beijing Chaoyang Hospital, Capital Medical University were retrospectively analyzed. There were 34 males and 43 females, aged (61.4±10.8) years old. The peri-operative data, long-term prognosis and stenosis of allogenic vein were analysed. Risk factors of stenosis were analyzed by the Cox proportional hazards model. Patients were followed up by outpatient visits or by telephone.Results:Pancreatic cancer had invaded the junction of portal vein/superior mesenteric vein (SMV) in 41 patients, SMV in 22 patients and portal vein in 14 patients. The length of venous resection was (3.7±1.0) cm, the tumor longest diameter was (3.8±1.6) cm, lymph node metastasis was present in 57 patients, R 0 resection was carried out in 70 patients, and the postoperative complication rate was 29.9% (23/77). The survival rates in 6 months, 1-year and 2-year were 84.1%, 52.3% and 32.9% respectively. Mild venous stenosis occurred in 4 patients (5.2%), moderate stenosis in 9 patients (11.7%) and severe stenosis in 11 patients (14.3%). A vascular resection length of more than 3 cm ( RR=4.602, 95% CI: 1.657-12.781, P=0.003) and tumor recurrence ( RR=8.529, 95% CI: 1.129-64.448, P=0.038) were independent risk factors for long-term moderate and severe stenosis of allogeneic vein. Conclusion:It was safe and feasible for allogenic vein to be used to reconstruct the portal venous system in resection of borderline resectable pancreatic cancer. Long-term stenosis of the allogenic vein was related to a length of vascular resection of more than 3 cm and recurrence of tumor.

Objective: To explore the status of PM 2.5 pollution in school classrooms and the student exposure level, and to provide basic data to safeguard the health of students. Methods: This study continuously monitored the PM 2.5 levels of 16 naturally ventilated classrooms in eight primary and secondary schools in Jiamusi for one academic year using an online environmental monitoring instrument. At the same time, outdoor PM 2.5 data was captured for comparative research, and student exposure to PM 2.5 during school hours was evaluated. Results: The average concentration of PM 2.5 in the classroom in the spring and autumn semesters was (26.93±24.7) and (31.85±30.37)μg/m 3, respectively, and the indoor/outdoor ratio ( I/O ) was 0.92 and 0.95, respectively, which indicated a strong correlation between them. The daily average concentration of all classrooms during both semesters was ( 28.93 ±26.85)μg/m 3, which was slightly higher than the average concentration of (27.53±26.53)μg/m 3 during the daytime when students were in school. In addition, the concentration on workdays was higher than that observed on weekends, and this was termed the "weekend effect". The indoor PM 2.5 concentration was lower on higher floors. The comprehensive exposure concentration of students during school was 28.48 μg/m 3 in spring semester and 31.87 μg/m 3 in autumn semester. Conclusion PM 2.5 levels in the classrooms varied according to time, the horizontal space, and the vertical space, and the level of indoor PM 2.5 pollution largely depended on outdoor pollution sources. Differences in PM 2.5 exposure were observed between.

Objective To investigate the clinical efficacy of total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts for pancreatic cancer with vascular invasion.Methods The retrospective and descriptive study was conducted.The clinicopathological data of 9 patients with pancreatic cancer who underwent total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts in the Beijing Chao Yang Hospital of Capital Medical University from January 2014 to September 2016 were collected.There were 4 males and 5 females,aged from 53 to 78 years,with a median age of 60 years.Involvement of portal vein (PV) and (or) superior mesenteric vein (SMV),splenic vein or convergence was detected in patients by preoperative evaluation,which indicated borderline resectable pancreatic cancer.Patients underwent complete surgical resection of tumor and involved portal veins,and then underwent vascular and digestive tract reconstruction.Observation indicators:(1) intraoperative situations;(2) postoperative situations;(3) follow-up.Patients were followed up by telephone interview and outpatient examination to detect survival of patients up to October 2018.Measurement data with normal distribution were represented as Mean±SD,measurement data with skewed distribution were expressed as M (range),and count data were expressed as absolute number.Results (1) Intraoperative situations:9 patients underwent total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts successfully,including 1 undergoing total pancreaticoduodenectomy due to positive margin of pancreatic neck during pancreatico-duodenectomy for pancreatic head carcinoma,3 of pancreatic head carcinoma with portal vein involvement and atrophy of pancreatic body and tail,and 5 of carcinoma of pancreatic neck and body with portal vein involvement.The operation time,portal vein occlusion time,and volume of intraoperative blood loss were (573± 19) minutes,(21 ±4) minutes,and (717±33) mL.(2) Postoperative situations:4 of 9 patients had postoperative complications,including 2 with grade Ⅰ complication and 2 with grade Ⅱ complication.There was no grade Ⅲ or above complication.No anastomotic stenosis or thrombus formation after reconstruction for portal vein.The perioperative complications were cured after conservative treatment.Duration of postoperative hospital stay was 17 days (range,10-25 days).Nine patients underwent subcutaneous injection of insulin to control blood glucose during the period fasting for solids and liquids.After resuming the semi-liquid diet of diabetes,patients received subcutaneous injection of rapid acting insulin before meals combined with subcutaneous injection of long-acting insulin before bedtime,with a insulin need of 24-36 U/d.Patients had postprandial blood sugar level of 8-11 mmol/L,without unmanageable hyperglycemia orlong-term application of insulin pump.Patients received oral trypsin pancreatin instead of trypsin,with no gastrointestinal symptoms such as bloating and steatorrhea,no malnutrition.Of 9 patients,2 had well-differentiated adenocarcinoma,4 had moderately differentiated adenocarcinoma,and 3 had poor-differentiated adenocarcinoma.There were 3 patients with no vascular invasion,1 with endangidic invasion,5 with tumor infiltration of tunica adventitia vasorum.One of 9 patients was in IIA stage of TNM staging,3 were in the II B stage,and 5 were in IIIB stage.The negative rate of pathological sections for excised specimen margin was 8/9.(3) Follow-up:9 patients were followed up for 7-37 months,with a median follow-up time of 15 months.Four patients survived,4 died of tumor recurrence and metastasis,and 1 died of cerebrovascular accident.Conclusion Total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts is safe and feasible for pancreatic cancer involving portal vein,splenic vein or junction.

Objective To study the impact on the use of branched vascular allografts in the prevention of left regional portal hypertension after pancreatic cancer operations.Methods This retrospective study included 25 patients who underwent pancreaticoduodenectomy for pancreatic head cancer which involved the portal vein,superior mesenteric vein and splenic venous confluence between January 2011 to December 2017 in the Beijing Chao Yang Hospital,Capital Medical University.These patients underwent "en bloc" resection of the spleno-mesenterio-portal (SMS) venous axis with replacement of a branched vascular allografts.They were studied to see whether gastroesophageal varices were found on gastroscopy and whether there were any changes in leukocyte,platelet and splenic volume before and after the operation to determine the incidence of left regional portal hypertension after operation.Results During the follow-up period,all the portal vein,superior mesenteric vein and splenic vein anastomoses were unobstructed and without any thrombosis.No new varices were found on gastroscopy.There were no significant differences in the white blood cell count,platelets count and splenic volume before and after the operations (all P＞0.05).The 25 patients had no left regional portal hypertension.Survival time and one year survival rate of the patients were (20.2±3.7) months and 44.0％.Conclusion Branched vascular allografts effectively prevented the occurrence of left regional portal hypertension after radical pancreaticoduodenectomy with resection of SMP.

Objective To evaluate the prognosis and related risk factors in patients with primary liver cancer after liver transplantation. Methods We retrospectively analyzed the clinical data of 298 patients who underwent liver transplantation between January 2013 and December 2017 at Beijing Chaoyang Hospital of Capital Medical University. 121 patients with primary liver cancer on postoperative pathological diagnosis were included into this study. The patients included 108 males and 13 females, aged from 31 to 70 years, with an average of (52. 7 ± 8. 7) years. The prognosis and the related risk factors on prognosis were analyzed. The survival curve was drawn by the Kaplan-Meier method, and the survival rate was compared by the log-rank test. Multivariate Cox regression was used to analyze the prognostic factors. Results Of the 121 patients who were enrolled in this study, 5 patients died during the perioperative period, making a perioperative mortality rate of 4. 1% (5/121). The remaining 115 patients were followed up and the followed up rate was 95. 0% (115/121). The overall 1-, 2- and 3-year survival rates were 81. 0% , 74. 6% and 70. 2% , respectively. The median survival was 41. 5 months. Multivariate analysis showed that preoperative Child grading (RR=3. 028, 95% CI: 1. 625～5. 643) and microvascular invasion (RR=7. 165, 95% CI: 2. 237～22. 951) were independent risk factors of prognosis. The worse the preoperative Child grading, the worse was the prognosis. The prognosis of patients with microvascular invasion was also poor. Conclusions The overall prognosis of patients with primary liver cancer after liver transplantation was good. Preoperative Child grading and pathological microvascular invasion were the main risk factors of prognosis after liver transplantation carried out for primary liver cancer.

Objective: To analyze the application of vascular replacement technique with allogenic blood vessel in radical resection for pancreatic carcinoma. Methods: The clinical data of 33 patients with vascular invasion of pancreatic carcinoma who underwent radical resection from April 2013 to April 2017 in Department of Hepatobiliary Surgery, Beijing Chaoyang Hospital were retrospectively analyzed. There were 14 males and 19 females with age of (62.5±10.6)years(ranging from 35 to 78 years). Vascular replacement technique with allogenic blood vessel was used on all patients who underwent radical resection for pancreatic carcinoma. The operation procedure was made according to the specific location of the carcinoma, and the allogenic blood vessel was selected according to the type of vascular invasion. The matching vessel was selected for replacement to the patient who was invaded only one vessel. And the "Y" type of iliac vein was selected for replacement to the patient who was invaded the confluence of portal vein, splenic vein and superior mesenteric vein. After the operation, the patients were followed up by telephone and outpatient review. Results: All of 33 patients were successfully completed the operations. There were 28 patients underwent pancreaticoduodenectomy with vascular replacement, and 5 patients underwent total pancreatectomy with vascular replacement. All the patients were confirmed pancreatic carcinoma and R0 resection according to the postoperative pathology. There were 16 patients with the carcinoma invasion the confluence of portal vein, splenic vein and superior mesenteric vein, 12 patients with the carcinoma invasion the superior mesenteric vein, and 5 patients with the carcinoma invasion the portal vein. There was no perioperative death in this group and no complications related to allogenic blood vessel. The incidence of postoperative complications was 18.2% (6/33), and the incidence of pancreatic fistula was 6.1% (2/33), all of which were biochemical fistula. There were 32 patients were followed up, and the follow-up rate was 96.9%. The median survival time was 14.6 months. The half-year, 1-year and 2-year survival rates were 75.6%, 37.6% and 27.4%. Conclusion The application of vascular replacement technique with allogenic blood vessel for pancreatic carcinoma has a great significance for improving the R0 resection rate and the prognosis of patients.

Objective To investigate the clinical characteristics and the related risk factors of pulmonary infection in patients after liver transplantation.Methods The clinical data of 298 patients who underwent liver transplantation in the Beijing Chaoyang Hospital between January 2013 and December 2017 were retrospectively stndied.The patients were divided into the infection group (n =58) and the control group (n =240) according to whether they had pulmonary infection.The characteristics,diagnosis,treatment,prognosis and risk factors of pulmonary infection were analyzed.Results Pulmonary infection occurred in 58 patients (19.5％) after liver transplantation.Eight patients died in the infection group of pulmonary infection.The mortality rate was 13.8％.The most common pathogenic bacteria were Acinetobacter bauman,Pseudomonas aeruginosa and Klebsiella pneumoniae,which accounted for 28.8％,20％ and 13.8％,respectively for the pulmonary infection.Multivariate analysis showed that the neutrophil ratio,and intensive care unit (ICU) hospitalization time were independent risk factors of pulmonary infection (P ＜ 0.05).Conclusions Pulmonary infection was common after liver transplantation.The treatment strategy should be the use of rational antibiotics and intensive pulmonary management.The neutrophil ratio and ICU hospitalization time were the risk factors of pulmonary infection.