1.Three-dimensional finite element analysis of one-piece computer aided design and computer aided manufacture involved zirconia post and core
Tuanfeng ZHOU ; Xianghao ZHANG ; Xinzhi WANG
Journal of Peking University(Health Sciences) 2015;(1):78-84
Objective:To analyze the biomechanics trait of one-piece computer aided design and com-puter aided manufacture ( CAD/CAM ) zirconia post and core by the three-dimensional finite element . Methods:The three-dimensional finite element models of three upper central incisors restored with one -piece CAD/CAM zirconia post and core ( group 1 ) , refabricated zirconia post and hot-pressed porcelain core ( group 2 ) , and cast gold alloy post and core ( group 3 ) were built by geometry method respectively . 100 N vertical loading through the central incisor models long axis and 100 N loading along directing at an angle of 45°with the models long axis were used to imitate the central incisor stress state in biting and mandible physiological protraction movement .Results:Under vertical loading , the restored teeth without dentin ferrule, the maximum Von-Mises stress value of the tooth root in group 1 was the least(11.02 N), which was the largest (13.17 N)in group 2.The stress became weaker from the upper to the lower of the tooth root.The maximum Von-Mises stress value of the tooth root , post and core became smaller while the restored teeth with the 2.0 mm high dentin ferrule.Under directing at an angle of 45°loading, without the design of dentin ferrule in the restored teeth , the maximum Von-Mises stress value of the post and core in group 1 was the greatest(20.45 N), while that stress of post and core in group 3 was the smallest (13.61 N).With 2.0 mm high dentin ferrule design in the restored teeth , the tooth root stress became weaker.The maximum Von-Mises stress value of the tooth root was the greatest (14.10 N) in group 3, but which was the lowest (13.38 N) in group 1.Conclusion:The results of the three-dimensional finite element analysis infers that one-piece zirconia post and core restoration is more beneficial to disperse the bite force than the prefabricated zirconia post and the cast gold alloy post and core .The one-piece of zirconia post and core is good to protect the teeth and keep the restoration intact .
2.Comparison of soft and hard tissue stability between immediate implant and delayed implant in maxillary anterior region after loading 2 years
Minjie WU ; Xianghao ZHANG ; Lidong ZOU ; Feng LIANG
Journal of Peking University(Health Sciences) 2015;(1):67-71
Objective: To compare the peri-implant tissue stability between immediate implant and delayed implant in maxillary anterior region after loading 2 years.Methods: In the study, 38 patients with single anterior tooth loss in the Second Clinical Division of Peking University School and Hospital of Stomatology from October 2010 to December 2011 were enrolled , and 43 implants were inserted .The gin-gival contour was induced using implant-supported temporary crowns prior to restoration till permanent prostheses delivered .The gingival papilla height , labial gingival margin level and peri-implant bone level were measured immediately after the permanent restoration and 2 years later .Results: In the study , 16 patients were treated by immediate implant for 17 implants;22 patients were treated by delayed im-plant for 26 implants .The implant stability quotient ( ISQ ) value of the 2 groups showed no significant difference before permanent restoration (P>0.05).In all the cases after loading 2 years, the average mesial gingival papilla height in the implant area of the immediate group and delayed group increased by (0.15 ±0.42) mm and (0.06 ±0.65) mm, respectively;the distal gingival papilla height increased by (0.06 ±0.50) mm and (0.02 ±0.57) mm respectively;while the labial gingival margin level shrinka-ges were (0.15 ±0.23) mm and (0.15 ±0.46) mm, respectively.The peri-implant bone losses in the mesial side were (0.67 ±0.35) mm and (0.69 ±0.49) mm, respectively, while in the distal side were (0.73 ±0.31) mm and (0.75 ±0.48) mm, respectively.All these indicators showed no significant difference between the 2 groups ( P>0 .05 ) .Conclusion:Both the cases obtained optimizer results after loading 2 years, and the soft and hard tissues around the implant were very stable , which means that both the protocols can achieve reliable therapeutic effects .If we can handle the indications , immediate implant for anterior teeth shows similar efficacy with delayed implant in the short term .But immediate implant in terms of shortening the course of treatment is clearly superior to delayed implant .
3.Construction and identification of recombinant human neutrophil gelatinase-associated lipo1calinlinear multi-epitope peptide
Xianghao ZHANG ; Zhiyang LI ; Hongpan XU ; Yanyan XIA ; Lu PANG ; Jin SI
Chinese Journal of Laboratory Medicine 2016;39(5):380-385
Objective The feasibility of predicting the B-cell epitopes of human Neutrophil Gelatinase-Associated Lipocalin (NGAL) was discussed by applicating bioinformatics technology.Linear epitope molecules that have diagnostic value were screened and these recombinant linear multi-epitope peptides were constructed,and expressed.The immunogenicity of the recombinant linear multi-epitope peptides were also identified.Methods NGAL amino acid sequence was got from GenBank in the Department of Clinical Laboratory of the Second Affiliated Hospital of Nanjing Medical University in July 2015,the Predicted,ABCpred,BepiPred,BcePred,and Lasergene softwares were used to predict the linear B cell epitope prediction.The predict epitopes were constructed and prokaryotic expressed,and then the single epitope antigens which could reacted with commercially available polyclonal NGAL antibody were screened out by Western blot.Finally,the multi-epitope peptide was constructed,expressed,and identified through immunoreactions.Results Eight possible epitopes were obtained after prediction.pET32a-N1-N8 prokaryotic expression vector were used to express the predict epitopes.After purification and Western blot analysis,three of the epitopes have strong antigenicity,and then a soluble fusion protein was expressed and obtained from the multi-epitope prokaryotic expression vector pET22b-Ngal_MEP1.The fusion protein was successfully purified by Ni2 + affinity column.Western blot analysis showed that the fusion protein had a strong antigenicity.Conclusions The constructed multi-epitope linear NGAL antigen peptides can obtain high soluble expression in prokaryotic expression system,and have a strong immunoreactivity,which can be used in subsequent antibody preparation.
4.Influencing factors of textbook outcomes in liver surgery after radical resection of gallbladder carcinoma: a national multicenter study
Zhipeng LIU ; Xuelei LI ; Haisu DAI ; Weiyue CHEN ; Yuhan XIA ; Wei WANG ; Xianghao YE ; Zhihua LONG ; Yi ZHU ; Fan HUANG ; Chao YU ; Zhaoping WU ; Jinxue ZHOU ; Dong ZHANG ; Rui DING ; Wei CHEN ; Kecan LIN ; Yao CHENG ; Ping YUE ; Yunfeng LI ; Tian YANG ; Jie BAI ; Yan JIANG ; Wei GUO ; Dalong YIN ; Zhiyu CHEN
Chinese Journal of Digestive Surgery 2023;22(7):866-872
Objective:To investigate the influencing factors of textbook outcomes in liver surgery (TOLS) after radical resection of gallbladder carcinoma.Methods:The retrospective case-control study was conducted. The clinicopathological data of 530 patients who underwent radical resection of gallbladder carcinoma in 15 medical centers, including the First Affiliated Hospital of Army Medical University et al, from January 2014 to January 2020 were collected. There were 209 males and 321 females, aged (61±10)years. Patients underwent radical resection of gallbladder carcinoma, including cholecystectomy, hepatectomy, invasive bile duct resection, and lymph node dissection. Observation indicators: (1) situations of TOLS; (2) influencing factors of TOLS. Measure-ment data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the independent sample t test. Measurement data with skewed distribution were represented as M( Q1, Q3), and comparison between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Comparison of ordinal data between groups was conducted using the Mann-Whitney U test. The univariate analysis was conducted using the corresponding statistical methods based on data type, and variables with P<0.10 were included in multivariate analysis. Multivariate analysis was conducted using the Logistic stepwise regression model. Results:(1) Situations of TOLS. All 530 patients underwent radical resection of gallbladder carcinoma, and there were 498 cases achieving R 0 resection, 508 cases without ≥grade 2 intra-operative adverse events, 456 cases without postoperative grade B and grade C biliary leakage, 513 cases without postoperative grade B and grade C liver failure, 395 cases without severe com-plications within postoperative 90 days, 501 cases did not being re-admission caused by severe com-plications within postoperative 90 days. Of the 530 patients, 54.53%(289/530) of patients achieved postoperative TOLS, while 45.47%(241/530) of patients did not achieve postoperative TOLS. (2) Influencing factors of TOLS. Results of multivariate analysis showed that American Society of Anesthesiologists classification >grade Ⅱ, preoperative jaundice, T staging as T3?T4 stage, N staging as N2 stage, liver resection as right hemi-hepatectomy, and neoadjuvant therapy were independent factors influencing TOLS in patients undergoing radical resection of gallbladder carcinoma ( odds ratio=2.65, 1.87, 5.67, 5.65, 2.55, 3.34, 95% confidence interval as 1.22?5.72, 1.18?2.95, 2.51?12.82, 2.83?11.27, 1.41?4.63, 1.88?5.92, P<0.05). Conclusion:American Society of Anesthesiologists classification >grade Ⅱ, preoperative jaundice, T staging as T3?T4 stage, N staging as N2 stage, liver resection as right hemi-hepatectomy, and neoadjuvant therapy are independent factors influencing TOLS in patients undergoing radical resection of gallbladder carcinoma.
5.Acute effect of ambient fine particulate matter on heart rate variability: an updated systematic review and meta-analysis of panel studies.
Zhiping NIU ; Feifei LIU ; Baojing LI ; Na LI ; Hongmei YU ; Yongbo WANG ; Hong TANG ; Xiaolu CHEN ; Yuanan LU ; Zilu CHENG ; Suyang LIU ; Gongbo CHEN ; Yuxiao ZHANG ; Hao XIANG
Environmental Health and Preventive Medicine 2020;25(1):77-77
BACKGROUND:
Decreased heart rate variability (HRV) is a predictor of autonomic system dysfunction, and is considered as a potential mechanism of increased risk of cardiovascular disease (CVD) induced by exposure to particulate matter less than 2.5 μm in diameter (PM
METHODS:
An updated systematic review and meta-analysis of panel studies till November 1, 2019 was conducted to evaluate the acute effect of exposure to ambient PM
RESULTS:
A total of 33 panel studies were included in our meta-analysis, with 16 studies conducted in North America, 12 studies in Asia, and 5 studies in Europe. The pooled results showed a 10 μg/m
CONCLUSION
Short-term exposure to PM
Adult
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Aged
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Aged, 80 and over
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Air Pollutants/analysis*
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Air Pollution/analysis*
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Female
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Heart Rate/drug effects*
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Humans
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Male
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Middle Aged
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Particulate Matter/analysis*
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Young Adult