1.Experimental study on mechanical properties of the ventral and the dorsal tissues of porcine descending aorta.
Xiaona LI ; Lingfeng CHEN ; Zhipeng GAO ; Jiahe LIU ; Weiyi CHEN
Journal of Biomedical Engineering 2019;36(4):596-603
The mechanical properties of the aorta tissue is not only important for maintaining the cardiovascular health, but also is closely related to the development of cardiovascular diseases. There are obvious differences between the ventral and dorsal tissues of the descending aorta. However, the cause of the difference is still unclear. In this study, a biaxial tensile approach was used to determine the parameters of porcine descending aorta by analyzing the stress-strain curves. The strain energy functions Gasser-Ogden-Holzapfel was adopted to characterize the orthotropic parameters of mechanical properties. Elastic Van Gieson (EVG) and Sirius red stain were used to observe the microarchitecture of elastic and collagen fibers, respectively. Our results showed that the tissue of descending aorta had more orthotropic and higher elastic modulus in the dorsal region compared to the ventral region in the circumferential direction. No significant difference was found in hyperelastic constitutive parameters between the dorsal and ventral regions, but the angle of collagen fiber was smaller than 0.785 rad (45°) in both dorsal and ventral regions. The arrangement of fiber was inclined to be circumferential. EVG and Sirius red stain showed that in outer-middle membrane of the descending aorta, the density of elastic fibrous layer of the ventral region was higher than that of the dorsal region; the amount of collagen fibers in dorsal region was more than that of the ventral region. The results suggested that the difference of mechanical properties between the dorsal and ventral tissues in the descending aorta was related to the microstructure of the outer membrane of the aorta. In the relatively small strain range, the difference in mechanical properties between the ventral and dorsal tissues of the descending aorta can be ignored; when the strain is higher, it needs to be treated differently. The results of this study provide data for the etiology of arterial disease (such as arterial dissection) and the design of artificial blood vessel.
Animals
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Aorta, Thoracic
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physiology
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Biomechanical Phenomena
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Collagen
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Elastic Modulus
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Stress, Mechanical
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Swine
2.End-stage hemolytic rate of leukocyte-reduced RBCs in additive solution: a 5-year retrospective study
Yanhong WAN ; Yanyu LI ; Wen LIU ; Shijing PEI
Chinese Journal of Blood Transfusion 2022;35(11):1157-1159
【Objective】 To evaluate the suitability of current quality standard for end-stage hemolytic rate required by Quality Requirements for Whole Blood and Blood Components in Taiyuan through a 5- year retrospective analysis of leukocyte-reduced RBCs in additive solution in Taiyuan Blood Center. 【Methods】 A total of 240 packs of leukocyte-reduced RBCs in additive solution were collected from January 2007 to December 2021. Hb concentration, hematocrit(Hct) and free Hb in supernatant at end-stage were detected to measure the hemolytic rate. And the hemolytic rate was then compared with the current standard(0.8%) to analyze whether statistical differences existed. 【Results】 The hemolytic rate of leukocyte-reduced RBCs in additive solution were 0.109±0.123 in 2017, 0.113±0.085 in 2018, 0.121±0.076 in 2019, 0.101±0.057 in 2020, and 0.128±0.089 in 2021, with no significant difference among each other (P>0.05). And 97.5% of the products showed an end-stage hemolytic rate below 0.4%, 0.83% among 0.6%~0.7%, and none over the standard of 0.8%. 【Conclusion】 The current national standard for end-stage hemolytic rate of leukocyte-reduced RBCs in additive solution might not be suitable for blood quality control in Taiyuan, and a much stricter criteria should be considered.
3.Prognostic value of Fluid-attenuated inversion recovery vascular hyperintensity-diffusion weighted imaging mismatch in patients with acute Ischemic stroke after thrombectomy
Qing LIU ; Xiaolong WANG ; Tianli ZHANG
Journal of Apoplexy and Nervous Diseases 2022;39(6):500-502
Objective We sought to investigate the prognostic value of FVH-DWI mismatch in acute stroke patients with lager vessel occlusion that received thrombectomy.Methods We reviewed our monocentric collected endovascular treatment database of patients with AIS from January 2020 to march 2021 who had received thrombectomy.All patients received pre-procedural MRI scans,Imaging protocols were assessed for FVH,distal FVH,proximal FVH and FVH-DWI mismatch.Results We found better collateral circulation (P<0.001),better functional independence (P<0.001) in patients with FVH-DWI mismatch.Multivariable logistic regression model indicated that FVH-DWI mismatch (OR 0.015) was associated with favorable clinical outcome.Conclusions Our study revealed that FVH-DWI mismatch was associated with the good outcome among patients with lager vessel occlusion
4.Relationship between clinics and the level of blood HBV DNA in different clinical types of hepatitis B.
Chinese Journal of Hepatology 2002;10(1):65-66
Adolescent
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Adult
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Aged
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Biomarkers
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blood
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Child
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Child, Preschool
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Clinical Medicine
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DNA, Viral
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blood
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Female
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Hepatitis B
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blood
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Hepatitis B Surface Antigens
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blood
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Hepatitis B e Antigens
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blood
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Hepatitis B virus
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chemistry
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genetics
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Humans
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Male
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Middle Aged
5.The Dilemma of Doctor-patient Communication: Objectification of Patient Role and Instrumentalization of Doctor-patient Relationship
Chinese Medical Ethics 2022;35(11):1241-1245
Doctor-patient communication needs mutual trust, mutual respect and joint participation, and the dilemma of which is embodied in objectification of the patient role and instrumentalization of the doctor-patient relationship. On the one hand, narrow positivism leads to the diagnosis and treatment practice of seeing "disease" without "pain", in which the patient is deprived of the subjectivity of telling and explaining. Under the rationalism of medical technology, professional terms regulate health cognition, through selective processing and presentation, the individualized experience of the patient is translated into standardized medical records, which leads to the objectification of the patient role. On the other hand, the consumptive society makes the doctor-patient relationship become an dehumanization service based on exchange, while the technical medicine makes the doctor-patient relationship ignore the narrative of emotion and human nature, leading to the instrumentalization of the doctor-patient relationship. The concept and practice of recovery encourage patients to rediscover the meaning and value of life, and its starting point is consistent with the aim of "bio-psychological-social" medical model. The core of recovery model is to regain the humanistic attribute of medicine, and promoting recovery discourse and projects will help to solve the dilemma of doctor-patient communication and build doctor-patient destiny community.
6.Research advances in the treatment of nonalcoholic fatty liver disease
Journal of Clinical Hepatology 2018;34(10):2232-2236
Nonalcoholic fatty liver disease (NAFLD) has become the leading cause of abnormal liver enzymes in healthy individuals in China. Due to the complex pathogenesis of NAFLD, no consensus has been reached on the treatment of this disease. However, in recent years, more and more studies have put forward more pathogeneses and corresponding treatment recommendations. This article introduces and summarizes the research advances in the treatment of NAFLD, including lifestyle intervention, drug treatment, eradication of Helicobacter pylori, surgical treatment, regulation of intestinal microecology, and gene therapy.
7.Experimental study on corneal biomechanical properties of rabbit eye after LASIK.
Aiyu WANG ; Weiyi CHEN ; Rui HE ; Xiaojun WANG ; Chunsheng LIU
Journal of Biomedical Engineering 2009;26(2):323-326
The biomechanical properties of 21 white New Zealand rabbits' corneas after Laser in situ keratomileusis (LASIK) were tested by use of one-dimension tensile test and creep test in the INSTRON 5544 mechanical machine. The cornea-related data from the experiments of one-dimension tensile test and creep test for an hour were obtained; a standard linear solid model was adopted to analyse the data, and the least square method was used to fit the viscoelastical coefficients of creep experiment on different corneas. We noticed there was certain difference between the LASIK groups and the normal group in respect to the corneal modulus of elasticity, the stiffness coefficients diminished with the increase of ablation depth; the anti-tensile ability of corneas also displayed some reduction. These findings indicate that the deeper the ablation goes, the easier will be the deformation after LASIK.
Animals
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Biomechanical Phenomena
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Cornea
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physiopathology
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surgery
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Elasticity
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Keratomileusis, Laser In Situ
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methods
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Lasers, Excimer
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therapeutic use
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Rabbits
8.Key enzymes in butanol fermentation by a facultative anaerobe Bacillus sp. TSH1.
Xiaorui DUAN ; Genyu WANG ; Hongjuan LIU ; Jianwei XUE ; Jian'an ZHANG
Chinese Journal of Biotechnology 2013;29(5):620-629
Bacillus sp. TSH1 is a butanol-producing microorganism newly isolated in our laboratory; it can grow and ferment under facultative anaerobic conditions, while sharing similar fermentation pathways and products with Clostridium acetobutylicum. To illustrate the relationships between the products and the enzyme activities in Bacillus sp. TSH1, key butanol- and ethanol-forming enzymes were studied, including butyraldehyde dehydrogenase, butanol dehydrogenase and alcohol dehydrogenase. The activities of the three enzymes increased rapidly after the initiation of fermentation. Activities of three enzymes peaked before 21 h, and simultaneously, product concentrations also began to increase gradually. The maximum activity of alcohol dehydrogenase was 0.054 U/mg at 12 h, butyraldehyde dehydrogenase 0.035 U/mg at 21 h and butanol dehydrogenase 0.055 U/mg at 15 h. The enzyme activities then decreased, but remained constant at a low level after 24 h, while the concentrations of butanol, acetone, and ethanol continued increasing until the end of the fermentation. The results will attribute to the understanding of the butanol metabolic mechanism, and provide a reference for further study of a facultative Bacillus metabolic pathway.
Alcohol Dehydrogenase
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metabolism
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Alcohol Oxidoreductases
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metabolism
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Aldehyde Oxidoreductases
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metabolism
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Anaerobiosis
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Bacillus
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classification
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genetics
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metabolism
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Butanols
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metabolism
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Fermentation
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Metabolic Networks and Pathways
9.An Experimental Study on Circumferential Mechanical Properties of Porcine Descending Thoracic Aorta
Lingfeng CHEN ; Baimei LIU ; Fen LI ; Meiwen AN
Journal of Medical Biomechanics 2018;33(6):E544-E550
Objective To study the mechanical properties of porcine descending aorta. Methods The porcine descending aortas were divided into 5 groups by the distance from the heart, and tissues in each group were subdivided into ventral-quadrant part and lateral-quadrant part. Stress-stretch curves were obtained by using uniaxial tension test. The moduli of elastic and collagen fiber and collagen fiber recruitment parameter of tissues in 5 groups (Position 1-5) were first analyzed by a classical mathematical model. Then the mechanical differences between tissues of ventral quadrant and lateral quadrant were compared. Results The modulus of circumferential collagen fibers increased gradually away from the heart. The modulus of circumferential elastic fibers had the same trend except for tissues at Position 5 (the most distal one). The elastic fibers modulus of tissues decreased at Position 5. At the most distal position, the circumferential and axial elastic fiber modulus of the lateral quadrant was lower than that of ventral quadrant by 19% and 33%, respectively. The axial and the elastic fiber modulus of the ventral quadrant was similar with that of tissues at Position 4 and 5. For the whole descending aorta, the circumferential collagen fiber modulus of the lateral quadrant was higher than that of ventral quadrant by 26% and the circumferential elastic fiber modulus of the lateral quadrant was higher than that of ventral quadrant by 16% at the proximal 4 positions. Conclusions The circumferential mechanical properties of porcine descending aorta were related with regions. The ventral quadrant of the most distal aorta showed abnormally soft trend. The research findings can be used to better understand the mechanism of aorta and improve the spatial accuracy of computer models.
10.Research progress on irradiation of seafood
Chao WANG ; Juancong DONG ; Xiaoming LIU ; Xuhong DANG
Chinese Journal of Radiological Health 2022;31(3):367-372
This paper summarizes and discusses the research and achievements in the effect of irradiation on extending the shelf life and quality guarantee period of seafood, on the quality of seafood, and on seafood sterilization, and seafood irradiation biological dosimeter study, and defines the concepts related to seafood irradiation. Moreover, we propose that irradiation sterilization on severe acute respiratory syndrome coronavirus 2 of cold-chain seafood and seafood irradiation dose control are the main research content and directions.