1.Finite element analysis for compression and expansion behavior of magnesium stent.
Hongliang CHEN ; Xiangkun LIU ; Guangyin YUAN ; Linlin ZHANG ; Zhonghua LI ; Qiyi LUO ; Feng LIN
Chinese Journal of Medical Instrumentation 2014;38(3):161-176
Magnesium stents have gained increasing interest as an ideal stent of future intervention. In order to study the deformation behavior of magnesium alloy stents in the interventional treatment, the finite element method was used to analysis the effects of different crimp and expansion dimensions on the mechanical properties (maximum stress, radial recoil rate, longitudinal shortening rate and radial strength). The results showed that crimping and expanding have a minimal influence on the stent radial strength. When the expansion size is same, the maximum equivalent stress and recoil rate decrease with the crimp size. When the crimp size is same, in contrast with the radial recoil rate, the maximum equivalent stress and longitudinal shortening rate increase with the expansion size. In addition the paper verified the radial strength-radial displacement curve obtained by FEM. Results are basically consistent, indicating the finite element method can efficiently provide researchers with reliable, high-quality design.
Alloys
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Finite Element Analysis
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Magnesium
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Stents
2.Effects of recombinant human NAMPT on physiological/biochemical indexes and brain structure in mice.
Journal of Zhejiang University. Medical sciences 2013;42(3):303-310
OBJECTIVETo observe the effect of recombinant human nicotinamide phosphoribosyl-transferase (NAMPT) on physiological/biochemical indexes and brain structure in mice.
METHODSWild type human recombinant NAMPT (10, 30 and 100 μg/kg) or H247A mutant NAMPT (with very weak enzymatic activity) were administrated by intravenous injection in mice once every 3 d for 32 d. The changes of body weight, blood pressure, heart rate, serum glucose, serum total cholesterol and triglyceride were determined, and the morphology of neuron, astrocyte and microglia in hippocampus were observed.
RESULTSThe injection of wild and mutated type NAMPT had no significant effect on body weight, blood pressure,heart rate, blood glucose, total cholesterol and triglyceride, and did not affect the morphology of neuron, astrocyte and microglia in hippocampus of mice.
CONCLUSIONElevation of plasma NAMPT may not induce metabolic and neuronal dysfunction in normal individual.
Animals ; Blood Glucose ; metabolism ; Brain ; anatomy & histology ; drug effects ; Cholesterol ; blood ; Cytokines ; pharmacology ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Nicotinamide Phosphoribosyltransferase ; pharmacology ; Recombinant Proteins ; pharmacology ; Triglycerides ; blood
3.Prediction of liver transplantation prognosis by transient elastography
Yuan DING ; Jianhua LIU ; Sheng YAN ; Qiyi ZHANG ; Lin ZHOU ; Haiyang XIE ; Shusen ZHENG
Chinese Journal of Organ Transplantation 2014;35(6):346-349
Objective To investigate the clinical value of transient elastography in adult after liver transplantation,by means of evaluating the correlation of liver stiffness measured by FibroScan with liver/renal functions.Method Forty-three patients received orthotopic liver transplant in our hospital during Dec.10,2013 and Mar.19,2014 were included in this study.Liver stiffness measurement (LSM) was performed after transplantation.Clinical data and laboratory tests including liver function and renal function were collected and analyzed.Result Bivariate correlation showed that body mass index (BMI),MELD score,graft-to-recipient weight ratio (GRWR) and warm ischemia time had no correlation with LSM.LSM at the 1st day after transplantation (LSM-1) showed no correlation with cold ischemia time,but LSM at the 7th day after transplantation (LSM-7) did,with R =0.335,P =0.028.LSM-1 showed positive correlation with the ICU time (R =0.488,P =0.001),but LSM-7 didn't.There was significantly positive correlation between LSM and aspartate aminotransferase,bile acid and creatinine,but no significant correlations were found between LSM and alanine arninotransferase,alkaline phosphatase,cholinesterase,gamma-glutamyl transferase,total bilirubin,direct bilirubin,indirect bilirubin,urea nitrogen and uric acid.The group with higher LSM-1 had longer ICU time than the lower group (9 d vs,7 d,P =0.013),and so was the hospital stay (34 d vs.23 d,P =0.023).For the LSM-7,there was no significant difference in ICU time and hospital stay between the two groups.The group with higher LSM-1 had higher serious complication incidence than the lower group (78.57% vs.27.59%,P =0.002),but the two groups in LSM-7 showed no significant difference in serious complication incidence.Conclusion The LSM partially correlates with the liver function and renal function of liver transplantation recipient,and may have its clinical value for assessing the early prognosis after liver transplantation.
4.Finite Element Analysis for Compression and Expansion Behavior of Magnesium Stent
Hongliang CHEN ; Xiangkun LIU ; Guangyin YUAN ; Linlin ZHANG ; Zhonghua LI ; Qiyi LUO ; Feng LIN
Chinese Journal of Medical Instrumentation 2014;(3):161-164,176
Magnesium stents have gained increasing interest as an ideal stent of future intervention. In order to study the deformation behavior of magnesium al oy stents in the interventional treatment, the finite element method was used to analysis the effects of different crimp and expansion dimensions on the mechanical properties (maximum stress, radial recoil rate, longitudinal shortening rate and radial strength). The results showed that crimping and expanding have a minimal influence on the stent radial strength. When the expansion size is same, the maximum equivalent stress and recoil rate decrease with the crimp size. When the crimp size is same, in contrast with the radial recoil rate, the maximum equivalent stress and longitudinal shortening rate increase with the expansion size. In addition the paper verified the radial strength-radial displacement curve obtained by FEM. Results are basical y consistent, indicating the finite element method can efficiently provide researchers with reliable, high-quality design.
5.Persisting lung pathogenesis and minimum residual virus in hamster after acute COVID-19.
Lunzhi YUAN ; Huachen ZHU ; Ming ZHOU ; Jian MA ; Rirong CHEN ; Liuqin YU ; Wenjia CHEN ; Wenshan HONG ; Jia WANG ; Yao CHEN ; Kun WU ; Wangheng HOU ; Yali ZHANG ; Shengxiang GE ; Yixin CHEN ; Quan YUAN ; Qiyi TANG ; Tong CHENG ; Yi GUAN ; Ningshao XIA
Protein & Cell 2022;13(1):72-77
Animals
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Antibodies, Neutralizing/biosynthesis*
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Antibodies, Viral/biosynthesis*
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Body Weight/immunology*
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COVID-19/virology*
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Disease Models, Animal
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Disease Progression
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Humans
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Immunohistochemistry
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Lung/virology*
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Male
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Mesocricetus
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Nasal Cavity/virology*
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RNA, Viral/immunology*
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SARS-CoV-2/pathogenicity*
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Severity of Illness Index
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Viral Load