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1.
Journal of Biomedical Engineering ; (6): 522-528, 2023.
Article in Chinese | WPRIM | ID: wpr-981571

ABSTRACT

The bionic optic nerve can mimic human visual physiology and is a future treatment for visual disorders. Photosynaptic devices could respond to light stimuli and mimic normal optic nerve function. By modifying (Poly(3,4-ethylenedioxythio-phene):poly (styrenesulfonate)) active layers with all-inorganic perovskite quantum dots, with an aqueous solution as the dielectric layer in this paper, we developed a photosynaptic device based on an organic electrochemical transistor (OECT). The optical switching response time of OECT was 3.7 s. To improve the optical response of the device, a 365 nm, 300 mW·cm -2 UV light source was used. Basic synaptic behaviors such as postsynaptic currents (0.225 mA) at a light pulse duration of 4 s and double pulse facilitation at a light pulse duration of 1 s and pulse interval of 1 s were simulated. By changing the way light stimulates, for example, by adjusting the intensity of the light pulses from 180 to 540 mW·cm -2, the duration from 1 to 20 s, and the number of light pulses from 1 to 20, the postsynaptic currents were increased by 0.350 mA, 0.420 mA, and 0.466 mA, respectively. As such, we realized the effective shift from short-term synaptic plasticity (100 s recovery of initial value) to long-term synaptic plasticity (84.3% of 250 s decay maximum). This optical synapse has a high potential for simulating the human optic nerve.


Subject(s)
Humans , Quantum Dots , Bionics , Oxides , Optic Nerve
2.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 267-272, 2023.
Article in Chinese | WPRIM | ID: wpr-976562

ABSTRACT

The four properties of Chinese herbal medicine have a history of several thousand years and are one of the important theoretical guides for the clinical application of Chinese herbal medicine. However, there have been few reviews of research methods and techniques for the four properties of Chinese herbal medicine in recent years. Therefore, this article summarized the advances and techniques for the four properties of Chinese herbal medicine by screening relevant literature on the four properties of Chinese herbal medicine and clarifying the characteristics, advantages, and applicable objects of each technique, in order to provide references for in-depth research on the four properties in the future. Chinese databases such as China national knowledge infrastructure (CNKI), Wanfang data, and VIP, as well as international databases including PubMed, Cochrane Library, and EMbase were searched for relevant literature on the four properties of Chinese herbal medicine. The advances, research objects, and research techniques involved in the literature were extracted, classified, and summarized. Currently, the research techniques for the four properties of Chinese herbal medicine mainly include six categories, i.e., literature data research, network pharmacology, biothermodynamics, cell biology, proteomics, and metabolomics. The research hierarchy can be divided into micro-level, small-level, medium-level, and macro-level. The research objects used in each experimental study are different, mainly single Chinese herbal medicine, Chinese herbal monomers, targets, microbial communities, cells, mice, and rats. Different research techniques explain the four properties of Chinese herbal medicine from different dimensions, which overall indicate the material basis of the four properties of Chinese herbal medicine. In future research, the interpretation of the four properties of Chinese herbal medicine can be first located at the research hierarchy, then corresponding research techniques can be selected according to the research hierarchy, and research indicators can be determined to obtain research conclusions. This can help researchers of traditional Chinese medicine effectively carry out research design and perform related experiments on the four properties of Chinese herbal medicine.

3.
Chinese Journal of Health Management ; (6): 241-245, 2022.
Article in Chinese | WPRIM | ID: wpr-932968

ABSTRACT

Objective:To explore the application effect of the intelligent interactive health education model in the health management of the smokers with high-risk of chronic obstructive pulmonary disease (COPD).Methods:From September 2019 to January 2020, 72 smokers with high-risk of COPD were recruited from Health Management Center, the First Affiliated Hospital of Nanjing Medical Universit y. The subjects were randomly divided into traditional group (35 cases) and intelligent group (37 cases) according to the intervention model. The traditional group used the method of mailing health education materials, while the intelligent group sent health education materials with the help of mobile intelligent platform for interactive feedback and intervention. After 12 weeks of intervention, the subjects′ nicotine dependence, international physical activity, population satisfaction, time consumption for follow-up and other indicators were compared. Results:After the intervention, the score of nicotine dependence in the intelligent group was lower than that in the traditional group [(1.86±1.48) vs (3.77±1.66), P<0.05], the number of smoking cessation cases was more than that in the traditional group (11 vs 1, P<0.05), the number of cases with significant improvement in the score of international physical strength scale was significantly improved than that in the traditional group (15 vs 0, P<0.01), and the satisfaction was higher than that in the traditional group (97.30% vs 42.85%, P<0.01), and the time consumption was less than that in the traditional group [(18.03±2.96) vs (25.14±2.64) min, P<0.01]. Conclusion:The intelligent interactive health education model can improve the health education effect of the smokers with high risk of developing COPD, and improve the health behavior of the population.

4.
Chinese Journal of Health Management ; (6): 751-757, 2022.
Article in Chinese | WPRIM | ID: wpr-957238

ABSTRACT

Objective:To analyze the influence of lifestyle changes on body weight and metabolic parameters during the early stage of corona virus disease 2019 (COVID-19) epidemic and regular epidemic prevention period in physical examination population.Methods:A total of 801 subjects from Nanjing enterprises and institutions who underwent physical examination in the Department of Health Promotion Center, the First Affiliated Hospital of Nanjing Medical University in May of 2019 to 2021 were included in this study. The basic information and data of body mass index, fasting blood glucose, total cholesterol, low density lipoprotein cholesterol (LDL-C), triglyceride and uric acid were collected. Information about dietary and exercise habits was obtained through pre-examination questionnaires. The data of 2019 was set as baseline data, data of 2020 represented information during the early stage of COVID-19 epidemic and data of 2021 represented information in regular epidemic prevention period. The subjects were divided into underweight group, normal weight group, overweight group, and obese group according to the body mass index at baseline. The Friedman test was applied to compare changes in body mass index and metabolic parameters across the population. Chi-square test was used to compare changes in dietary and exercise habits. Multivariate logistic regression analysis was adopted to explore the influencing factors of body mass index changes.Results:During the early stage of COVID-19 epidemic, the proportion of weight gain was the highest in the underweight group (42.9%), the proportion of weight loss was the highest in the overweight group (24.2%), and the obese group has the most stable body weight (70.6%) ( P=0.004). Men ( OR=0.56, 95% CI: 0.36-0.87) were less likely to gain weight than women ( P=0.010). There was no significant differences in weight change among all groups in the regular epidemic prevention period ( P=0.380). During the early stage of COVID-19 epidemic, the levels of fasting blood glucose, total cholesterol and LDL-C were significantly lower than those of baseline [4.98 (4.66, 5.42) vs 5.23 (4.91, 5.66) mmol/L, 4.98 (4.36, 5.67) vs 5.11 (4.54, 5.77) mmol/L, 2.90 (2.45, 3.33) vs 3.23 (2.77, 3.74) mmol/L], and the uric acid level was higher [333.0 (275.5, 397.0) vs 311.0 (257.5, 368.0) μmol/L] (all P<0.001). In regular epidemic prevention period, the levels of body mass index, fasting blood glucose, total cholesterol and LDL-C were significantly higher than those in the early stage of the epidemic [24.0 (21.9, 26.3) vs 23.8 (21.7, 26.1) kg/m 2, 5.18 (4.85, 5.62) vs 4.98 (4.66, 5.42) mmol/L, 5.12 (4.42, 5.76) vs 4.98 (4.36, 5.67) mmol/L, 3.06 (2.59, 3.57) vs 2.90 (2.45, 3.33) mmol/L], while the uric acid was significantly lower [319.0 (265.0, 377.0) vs 333.0 (275.5, 397.0) μmol/L] (all P<0.001). During the early stage of the epidemic, the reduction proportion of unhealthy diet in the home group was significantly higher than that in the outing group (19.5% vs 11.4%), and the increment proportion of exercise in the outing group was significantly higher than that in the home group (5.1% vs 1.6%) (both P<0.05). In regular epidemic prevention period, the increase rate of unhealthy diet in the home group was significantly higher than that in the outing group (26.8% vs 13.0%) ( P<0.001), and there was no significant difference in exercise between the two groups ( P=0.325). During the early stage of COVID-19 epidemic and in the regular epidemic prevention period, unhealthy diet>3 times per week ( OR=3.85, 3.01, 95% CI: 1.74-8.51, 1.41-6.39) was positively correlated with weight gain, and regular exercise ( OR=4.35, 2.61, 95% CI: 2.05-9.23, 1.15-5.91) was positively correlated with weight loss (all P<0.05). Conclusions:During the early stage of COVID-19 epidemic and in the regular epidemic prevention period, the lifestyle in the physical examination population has an impact on body weight and metabolic indicators. In the early stage of the epidemic, unhealthy diet and exercise decreased, and metabolic indicators such as blood glucose and lipids decreased. People with low body weight tend to gain weight. In the regular epidemic prevention period, the subjects′ exercise increased but unhealthy diet also increased, and blood glucose, lipid and body weight elevated significantly.

5.
Acta Pharmaceutica Sinica B ; (6): 1213-1224, 2022.
Article in English | WPRIM | ID: wpr-929357

ABSTRACT

Silicosis is a leading cause of occupational disease-related morbidity and mortality worldwide, but the molecular basis underlying its development remains unclear. An accumulating body of evidence supports gasdermin D (GSDMD)-mediated pyroptosis as a key component in the development of various pulmonary diseases. However, there is little experimental evidence connecting silicosis and GSDMD-driven pyroptosis. In this work, we investigated the role of GSDMD-mediated pyroptosis in silicosis. Single-cell RNA sequencing of healthy and silicosis human and murine lung tissues indicated that GSDMD-induced pyroptosis in macrophages was relevant to silicosis progression. Through microscopy we then observed morphological alterations of pyroptosis in macrophages treated with silica. Measurement of interleukin-1β release, lactic dehydrogenase activity, and real-time propidium iodide staining further revealed that silica induced pyroptosis of macrophages. Additionally, we verified that both canonical (caspase-1-mediated) and non-canonical (caspase-4/5/11-mediated) signaling pathways mediated silica-induced pyroptosis activation, in vivo and in vitro. Notably, Gsdmd knockout mice exhibited dramatically alleviated silicosis phenotypes, which highlighted the pivotal role of pyroptosis in this disease. Taken together, our results demonstrated that macrophages underwent GSDMD-dependent pyroptosis in silicosis and inhibition of this process could serve as a viable clinical strategy for mitigating silicosis.

6.
Journal of Biomedical Engineering ; (6): 1103-1110, 2021.
Article in Chinese | WPRIM | ID: wpr-921851

ABSTRACT

China is the country with high incidence of high myopia in the world. High myopia can cause severe vision impairment. So far, there is no effective treatment for high myopia in clinic. Scleral collagen cross-linking surgery has been proven to be effective in preventing animal eye axial elongation


Subject(s)
Animals , Collagen , Cross-Linking Reagents , Finite Element Analysis , Photosensitizing Agents , Riboflavin , Sclera
7.
Journal of Biomedical Engineering ; (6): 869-876, 2021.
Article in Chinese | WPRIM | ID: wpr-921824

ABSTRACT

The effect of parasitic ions on the results of ultraviolet A (UVA) cross-linking in iontophoresis was still not clear. In this work, the porcine sclera was cross-linked by riboflavin lactate Ringer's solution (group A) and riboflavin normal saline (group B)


Subject(s)
Animals , Collagen , Cross-Linking Reagents , Ions , Iontophoresis , Permeability , Photosensitizing Agents/pharmacology , Riboflavin , Sclera , Swine , Ultraviolet Rays
8.
Chinese Journal of Blood Transfusion ; (12): 1296-1299, 2021.
Article in Chinese | WPRIM | ID: wpr-1003965

ABSTRACT

【Objective】 To develop an assay to determine β-lactam antibiotics using microcolumn gels and to study the β-lactam antibiotics present in the blood of patients and their clinical significances. 【Methods】 446 patients with a history of taking β-lactam antibiotics from January 2019 to June 2019 were randomly selected from Trauma Emergency Center, Department of Arthrosis, Department of Spine and Department of Bone Oncology of our hospital, and 4 mL(per capita) venous blood was collected. Irregular antibody screening, anti-globulin detection and drug antibody determination were performed by microcolumn gel method. The data of gender, age, disease, blood transfusion history and medication were collected. The test results and clinical data were retrospective analyzed. 【Results】 The yielding rate of antibody was 0.45%(2/446) in patients with a history of taking β -lactam antibiotics. 16.38%(73/446) of the samples were positive in direct antiglobulin test, and 64.38%(47/73) of them did not agglutinate with RBCs treated with drugs. The yielding rate of specific antibodies against drug was 4.93%(22/446), and the titer ranged from 2 to 128(8). 1 case of auto-IgM antibody, 1 case of blood group related antibody and 2 cases of non-specific protein adsorption were detected. The yielding rate of drug antibody in patients with blood transfusion history reached to 12.10 %(22/124), so it was also high in patients with bone tumor. 【Conclusion】 Direct antiglobulin assay is helpful for the detection of β-lactam antibodies. The negative results of antibody screening cannot completely exclude the presence of drug antibodies. The yielding rate of drug antibody can be greatly improved by specific drug antibody detection, and it was higher in transfused patients relative to non-transfused one.

9.
Chinese Journal of Endocrine Surgery ; (6): 365-372, 2020.
Article in Chinese | WPRIM | ID: wpr-863949

ABSTRACT

Objective:To investigate the relationship between lncRNA SNHG6 and breast cancer and its possible mechanism.Methods:Fluorescence quantitative PCR was used to detect the expression of SNHG6, miR-30-5p, and FKBP3 in human normal breast epithelial cell line MCF-10A and human breast cancer cell line MCF-7. According to the experiment content, MCF-7 cells were divided into the following groups:① si-NC group, si-SNHG6 group, si-NC+miR-30-5p inhibitor group and si-SNHG6+miR-30-5p inhibitor group;②miR-NC group, miR-30-5p inhibitor group, miR-30-5p inhibitor+sh-NC group and miR-30-5p inhibitor+sh-FKBP3 group. The expression of SNHG6 was inhibited by siRNA technology, and the miR-30-5p mimic (mimic) , inhibitor (inhibitor) and negative control (miR-NC) were transfected into MCF-7 cells by liposome-mediated method. A short hairpin RNA (shRNA) lentiviral expression vector targeting FKBP3 gene was constructed to inhibit FKBP3 expression. CCK-8, cell colony formation experiment, cell wound healing experiment and Transwell experiment were used to observe the proliferation, migration and invasion of MCF-7 cells in each group. Bioinformatics software, dual luciferase reporter gene experiment and Western blotting were used to analyze the targeting relationship between SNHG6 and miR-30-5p, miR-30-5p and FKBP3.Results:Compared with MCF-10A cells, the expression levels of SNHG6 and FKBP3 in MCF-7 cells increased significantly, while the expression levels of miR-30-5p decreased significantly ( t=21.097, P=0.000; t=17.812, P=0.000; t=33.671, P=0.000) . Compared with si-NC group, the proliferation activity of MCF-7 cells in the si-SNHG6 group was significantly inhibited ( t=19.569, P=0.000; t=25.077, P=0.000) , and the number of cell colonies formed significantly decreased ( t=34.071, P=0.000) . Migration and invasion of cells were also inhibited ( t=33.419, P=0.000; t=29.372, P=0.000) . There were complementary binding sites between miR-30-5p and SNHG6. The luciferase activity of miR-30-5p mimic and SNHG6-WT co-transfected group was significantly lower than that of miR-NC and SNHG6-WT co-transfected group ( t=31.596, P=0.000) . The proliferation, migration and invasion of MCF-7 cells in each group were significantly different ( F=268.014, F=398.483, F=244.962) . Compared with si-SNHG6 group, the proliferation, migration and invasion ability of MCF-7 cell in si-SNHG6+miR-30-5p inhibitor group increased significantly ( P=0.000) ; Compared with si-NC+miR-30-5p inhibitor group, the proliferation, migration and invasion ability of MCF-7 cells in si-SNHG6+miR-30-5p inhibitor group decreased significantly ( P=0.000) . There were complementary binding sites between miR-30-5p and 3’UTR of FKBP3. The luciferase activity of miR-30-5p mimic and FKBP3-WT co-transfected group was significantly lower than that of miR-NC and FKBP3-WT co-transfected group ( t=28.557, P=0.000) . After transfection, the FKBP3 protein expression of MCF-7 cells in each group was significantly different ( F=102.523) . Compared with miR-NC group, FKBP3 protein expression of miR-30-5p mimic group was significantly reduced, while FKBP3 protein expression of miR-30-5p inhibitor group was significantly increased ( P=0.000) . The proliferation, migration and invasion of MCF-7 cells in each group were significantly different ( F=177.036, F=285.530, F=217.992) . Compared with miR-30-5p inhibitor group and miR-30-5p inhibitor+sh-NC group, the proliferation, migration and invasion ability of MCF-7 cells in miR-30-5p inhibitor+sh-FKBP3 group was significantly decreased ( P=0.000 ) . Conclusion:Inhibiting the expression of miR-30-5p can reverse the inhibitory effect of down-regulation of SNHG6 on the proliferation, migration and invasion of MCF-7 cells.

10.
Journal of Biomedical Engineering ; (6): 608-613, 2020.
Article in Chinese | WPRIM | ID: wpr-828127

ABSTRACT

The decrease of corneal stiffness is the key factor leading to keratoconus, and the corneal collagen fiber stiffness and fiber dispersion are closely related to the corneal biomechanical properties. In this paper, a finite element model of human cornea based on corneal microstructure, namely collagen fiber, was established before and after laser assisted in situ keratomileusis (LASIK). By simulating the Corvis ST process and comparing with the actual clinical results, the hyperelastic constitutive parameters and corneal collagen fiber stiffness modulus of the corneal material were determined before and after refractive surgery. After LASIK, the corneal collagen fiber stiffness modulus increased significantly, and was highly correlated with central corneal thickness (CCT). The predictive relationship between the corneal collagen fiber stiffness modulus and the corresponding CCT before and after surgery was: = exp(9.14 - 0.009CCT ), = exp(8.82 - 0.008CCT ). According to the results of this study, the central corneal thickness of the patient can be used to estimate the preoperative and postoperative collagen fiber stiffness modulus, and then a personalized corneal model that is more consistent with the actual situation of the patient can be established, providing a theoretical reference for more accurately predicting the safe surgical cutting amount of the cornea.


Subject(s)
Humans , Biomechanical Phenomena , Cornea , Corneal Topography , Finite Element Analysis , Keratomileusis, Laser In Situ , Myopia
11.
International Journal of Cerebrovascular Diseases ; (12): 624-628, 2019.
Article in Chinese | WPRIM | ID: wpr-789087

ABSTRACT

It has been previously thought that calcification is a feature of the stability of atherosclerotic plaques. However, recent studies have shown that microcalcification in atherosclerotic plaques is significantly associated with plaque vulnerability. The relationship between atherosclerotic plaques and calcification is unclear, and the specific role of calcification in atherosclerotic plaques remains controversial.

12.
Chinese Critical Care Medicine ; (12): 867-872, 2019.
Article in Chinese | WPRIM | ID: wpr-754069

ABSTRACT

Objective To investigate the preventive effect of Xuebijing injection on acute lung injury induced by cardiopulmonary bypass (CPB) and the underlying mechanism. Methods ① In vivo experiment: 30 Sprague-Dawley (SD) rats were randomly divided into sham group, CPB group, Xuebijing pretreatment group (XBJ+CPB group) with 10 rats in each group. CPB model was reproduced in rats; and CPB was not performed in sham group, but only through arteriovenous puncture. In the XBJ+CPB group, 4 mL/kg Xuebijing injection was injected intraperitoneally 2 hours before CPB, sham group and CPB group were injected with equal volume of normal saline at the same time. The blood from femoral artery was analyzed 4 hours after operation, and the oxygenation index (PaO2/FiO2) was calculated. Then the rats were sacrificed to collect bronchoalveolar lavage fluid (BALF), and the lung permeability index (PPI) was calculated. The lung tissues were harvested, and the wet/dry weight ratio (W/D) of lung tissue was measured. The index of quantitative evaluation of alveolar injury (IQA) was measured. The levels of interleukins (IL-1, IL-6) and tumor necrosis factor-α(TNF-α) in lung tissue and BALF were measured by enzyme-linked immunosorbent assay (ELISA). The content of malondialdehyde (MDA) and the activities of myeloperoxidase (MPO) and superoxide dismutase (SOD) in lung tissue were detected by biochemical method. The microRNA-17-5p (miR-17-5p) expression in lung tissue was determined by quantitative reverse transcription-polymerase chain reaction (RT-qPCR).② In vitro experiments: type Ⅱ alveolar epithelial cells (AECⅡ) were cultured in vitro, and they were randomly divided into control group (the cells were treated by preoperative serum of CPB in patients with ventricular septal defect), CPB group (the cells were treated by serum after CPB in patients), and XBJ+CPB group (Xuebijing injection 10 g/L+serum after CPB in patients). After 12 hours of culture in each group, the expression of miR-17-5p was detected by RT-qPCR. AECⅡ cells were transfected with miR-17-5p mimic, inhibitor or corresponding control oligonucleotide (negative control), respectively, to observe the effect of miR-17-5p on Xuebijing regulating CPB-induced apoptosis rate and caspase-3 activity. Results ① In vivo experiment: compared with the sham group, the PPI, lung W/D ratio, IQA, and IL-1, IL-6, TNF-α in lung tissue and BALF, as well as MDA content and MPO activity in lung tissue were significantly increased, PaO2/FiO2 and SOD activity in lung tissue were significantly decreased. The parameters of the XBJ+CPB group were significantly improved, suggesting that Xuebijing pretreatment could improve CPB-induced ALI in rats. The expression of miR-17-5p in lung tissue of the CPB group was significantly down-regulated as compared with sham group (2-ΔΔCt: 0.48±0.13 vs. 1.00±0.11, P < 0.05);while the expression of miR-17-5p in the XBJ group was significantly up-regulated as compared with the CPB group (2-ΔΔCt: 1.37±0.09 vs. 0.48±0.13, P < 0.05), indicating that the improvement of Xuebijing injection on lung injury after CPB might be related to miR-17-5p. ② In vitro experiment: the changes in miR-17-5p expression in each group of AECⅡ cells confirmed in vivo results. After transfection of miR-17-5p mimic, the apoptotic rate and caspase-3 activity of each group were significantly lower than those transfected with negative control, and the decrease was more significant in the XBJ+CPB group [apoptotic rate: (7.37±0.95)% vs. (12.60±1.90)%, caspase-3 (A value): 0.82±0.09 vs. 1.37±0.08, both P < 0.05]. After transfection of miR-17-5p inhibitor, the apoptotic rate and caspase-3 activity of each group were significantly more than those transfected with negative control [in the XBJ+CPB group: apoptotic rate was (16.30±1.86)% vs. (12.60±1.90)%, caspase-3 (A value) was 1.78±0.13 vs. 1.37±0.08, both P < 0.05]. This indicated that the apoptosis of AECⅡ cells cultured in serum after CPB was significantly reduced by miR-17-5p, and further reduced by the pretreatment with Xuebijing. Conclusions Xuebiing injection can reduce the inflammatory reaction and oxidative stress of lung tissue in rats with ALI induced by CPB, and improve oxygenation. The mechanism may be related to up-regulation of miR-17-5p expression in AECⅡ cells and inhibition of apoptosis of AECⅡ cells.

13.
Chinese Journal of Medical Education Research ; (12): 684-687, 2019.
Article in Chinese | WPRIM | ID: wpr-753449

ABSTRACT

Objective To investigate the training effect of the case-based learning (CBL) teaching method on post competency of medical students. Methods Four classes of students majoring in nursing in China Medical University were enrolled and divided into experimental group and control group, with two classes in each group. In the teaching of medical chemistry, the CBL teaching method was adopted for the experimental group and the traditional teaching method was adopted for the control group, with the same teacher and teaching materials. Questionnaire survey and final examination were performed to assess the effect of the CBL teaching method on post competency of medical students, and SPSS 20.0 software was used for data analysis. Results The results of the questionnaire survey showed that the experimental group had better assessment indices of post competency. The results of the final examination showed that the experimental group had a significantly higher mean score of medical chemistry than the control group [(73.5 ±10.3) vs. (68.1 ±9.1)]. Conclusion The application of the CBL teaching method in medical chemistry can effectively improve the learning outcomes of medical students and train their post competency, and therefore, it holds promise for application in the teaching of basic medicine.

14.
Journal of Biomedical Engineering ; (6): 596-603, 2019.
Article in Chinese | WPRIM | ID: wpr-774166

ABSTRACT

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.


Subject(s)
Animals , Aorta, Thoracic , Physiology , Biomechanical Phenomena , Collagen , Elastic Modulus , Stress, Mechanical , Swine
15.
Journal of Biomedical Engineering ; (6): 613-618, 2019.
Article in Chinese | WPRIM | ID: wpr-774164

ABSTRACT

Study of the mechanical properties of in vivo corneal materials is an important basis for further study of corneal physiological and pathological phenomena by means of finite element method. In this paper, the elastic coefficient ( ) and viscous coefficient ( ) of normal cornea and keratoconus under pulse pressure are calculated by using standard linear solid model with the data provided by corneal visualization scheimpflug technology. The results showed that there was a significant difference of and between normal cornea and keratoconus cornea ( < 0.05). Receiver operating characteristic curve analysis showed that the area under curve (AUC) for , and their combined indicators were 0.776, 0.895 and 0.948, respectively, which indicated that keratoconus could be predicted by and . The results of this study may provide a reference for the early diagnosis of keratoconus and avoid the occurrence of keratoconus after operation, so it has a certain clinical value.


Subject(s)
Humans , Area Under Curve , Cornea , Physiology , Elasticity , Keratoconus , Pathology , ROC Curve , Viscosity
16.
Chinese Journal of Radiology ; (12): 954-959, 2017.
Article in Chinese | WPRIM | ID: wpr-666063

ABSTRACT

Objective To study the feasibility of diffusion tensor imaging(DTI) in assessment of lumbosacral neuropathy. Methods Eighteen patients with lumbosacral neuropathy (experimental group) and 20 healthy volunteers (control group) were enrolled prospectively in the neurological department by clinical symptoms and neuroelectrophysiology. The experimental group were divided into experimental subgroup A(demyelination group, 6 cases),subgroup B(axonal injury with demyelination group, 12 cases) based on electrophysiology.All of L4-SN nerves of the experiment group and the control group received DTI examination."Sowing points"as ROIs were placed in the proximal, middle and distal of bilateral L4-SN nerves by two experienced physicians.The average of the DTI parameters of 3 ROIs at each nerve were used as its final DTI parameters.Independent sample t test was used to evaluate the difference of the L4-SN DTI parameters between the experimental group and the control group.The differences of DTI parameters among the control group, the experimental subgroup A and the experimental subgroup B were compared by the nonparametric independent samples Kruskal-Wallis H test and the Nemenyi test. The ROC analysis was performed on the FA values and λ⊥values of the control and experimental groups.Results (1)The L4-SN FA values in the experimental group was significantly lower than those in the control group (t range from 4.11 to 6.36, P<0.05). The L4 and S1-SN ADC values of the experimental group were significantly higher than those of the control group (t range from - 4.77 to - 1.17, P<0.05). The L4-SN λ ⊥ values in the experimental group were significantly higher than those in the control group (t range from -5.30 to -2.57,P< 0.05). (2) L4-SN FA values (H values ranged from 18.5 to 30.6, P<0.05), λ⊥ values (H values ranged from 6.8 to 29.2, P<0.05) and L4, S1-SN ADC values (H values ranged from 6.8 to 19.6, P<0.05) were significantly different among control group, experimental subgroup A and experimental subgroup B. Nemenyi test showed there were significant differences in FA values (H values ranged from 18.4 to 30.1,P<0.05) and λ⊥ values (H values ranged from 6.2 to 29.0, P<0.05)) of L4-SN and in ADC values (H values ranged from 6.4 to 19.54, P<0.05) of L4,S1-SN between control group and experimental subgroup B. (3) The analysis of ROC of the experimental group and control group showed the AUC values of L4-SN FA values were 0.834, 0.745, 0.860, 0.772, 0.811 respectively, the sensitivity were 66.7%, 72.2%, 77.8%, 83.3% and 66.7% respectively, and the specificity were 91.7%,69.4%,80.6%,61.1% and 88.9% respectively. The AUC values of L4-SN λ⊥ values were 0.796, 0.656, 0.791, 0.701, 0.843 respectively, and the sensitivity were 55.6%, 50.0%, 66.7%, 97.2% and 88.9% respectively,and the specificity were 91.7% , 77.85% , 86.1% , 36.1% and 66.7% respectively. Conclusion DTI has the feasibility to evaluate lumbosacral neuropathy and it can identify patients with axonal injury with demyelination and healthy subjects.

17.
Journal of Practical Radiology ; (12): 1913-1916, 2017.
Article in Chinese | WPRIM | ID: wpr-664026

ABSTRACT

Objective To study radiographic classification of tarsometatarsal joint dislocation and postoperative imaging evaluation.Methods 74 patients with tarsometatarsal joint dislocation were included in this study.Tarsometatarsal joint dislocations were classified by the Myerson fracture displacements classification.All patients were evaluated according to the American Orthopedics Foot & Ankle Society (AOFAS)clinical rating systems.Results There were 19 patients with Myerson A,46 patients with Myerson B and 9 patients with Myerson C tarsometatarsal joint dislocation.39 distal tarsal bone fractures and 156 metatarsal fractures,with simultaneous scaphoid fractures in 10 patients were showed.All patients who were followed up and no infection.The AOFAS scale was categorized as excellent,good,fair or poor,and 22 patients were considered as excellent,29 patients as good,17 patients as fair and 6 patients as poor.Postoperative imaging evaluation required anatomical reduction of tarsometatarsal joint.On the anteroanterior radiogragh,the base medial edge of the second metatarsal bone and the medial edge of intermediate cuneiform were combined to form a straight line.The shortest distance between the base of the first metatarsal bone and the second metatarsal bone should be less than 2 mm.On the medial oblique radiogragh,a smooth line connecting the medial edge of the fourth metatarsal bone with the medial edge of cuboid bone always appeared.On the lateral radiogragh,the dorsal edge of the second metatarsal bone and intermediate cuneiform formed a smooth line.The height of metatarsus should not exceed the dorsal edge of corresponding cuneiform.The longitudinal arch angle was restored within normal limits.Conclusion The type-B tarsometatarsal joint dislocation is the most common type and frequently accompanies by multiple fractures.Intraoperative and postoperative multidirectional observation of anatomical reduction of tarsometatarsal joint dislocation can reduce incidence of posttraumatic arthritis.

18.
Chinese Journal of Medical Education Research ; (12): 265-268, 2017.
Article in Chinese | WPRIM | ID: wpr-608566

ABSTRACT

Objective This study discusses the effect of integrating method in the international students' basic chemistry class of medical colleges.Methods The integrating method was composed of the new teaching methods,such as PBL and micro-learning resources,and traditional method.The experimental group was composed of 76 students from the Class 1 of international students of Grade 2015 in clinical medicine of China Medical University,where integrating method was used,namely the teaching methods and means of problem based learning and micro class were integrated into the experimental courses,while the control group was composed of 80 students in Class 2 from the same major and grade,which was using the traditional method of teaching and practicing.A unified examination was applied to evaluate the teaching efficiency in both two groups and the teaching effect of the experimental group was investigated by questionnaire.The data was entered into SPSS 13.0 for two independent samples t-test.Results In the exams the students in the test group got higher scores than that in the control group.The average scores were (17.6 ± 4.5) and (16.0 ± 4.8) respectively (t=4.42,P=0.00),the differences were statistically significant.The effective recovery rate of the experimental group was 100%,and among them,97.4% (74) of the students thought that they should continue to use the integrating teaching.Conclusion The application of integrating teaching in the course of basic chemistry experiment can improve students' comprehensive ability,and the effect is better than the traditional teaching.

19.
Journal of Practical Stomatology ; (6): 95-99, 2017.
Article in Chinese | WPRIM | ID: wpr-619233

ABSTRACT

Objective:To evaluate the stress distribution and displacement pattern in the restoration of Stern-ERA attachment mandible removable partial denture (RPD) with different designs through three-dimensional (3D) finite element (FE) analysis.Methods:3D-FE models were established based on human CT data and manufacturer's catalog.Vertical and 45° lingual oblique forces of 100 N were applied on the artificial teeth of the RPD.Three ERA attachment partial dentures with different bracing arms were designed,namely the basic design,rest bracing arm design and cross-arch bracing arm design.The von Mises stresses and displacements of abutment teeth and mucosa under denture base were analysed.The displacement of denture bases was examined.Results:Under the vertical and oblique loading,the maximum yon Mises stress was found at the distal shoulder on the distal abutment.The maximun displacement was observed at the buccal and distal occlusal surfaces of the distal abutment.The maximum displacement on the abutment was found to be the highest in rest bracing arm design group (14.91 μm and 63.09 μm),followed by the basic design group (9.38 μm and 50.56 μm) and the cross-arch bracing arm design group exhibited the smallest displacement (8.85 μm and 47.31 μm).Conclusion:The basic design Stern_ERA attachment for unilateral mandible distal extension defect appears to be more reasonable compared with rest arm and crossing-arch arm design from biomechanical point of view.

20.
Chinese Journal of Tissue Engineering Research ; (53): 1301-1305, 2017.
Article in Chinese | WPRIM | ID: wpr-514909

ABSTRACT

BACKGROUND: Traction force generated by adherent cells exerts on the extracellular matrix or cell substrate through the interaction between actin and myosin, which involves a variety of physiological and pathological processes.OBJECTIVE: To review the fundamental principles and application of several traction force techniques.METHODS: The first author retrieved the databases of CNKI, WanFang, PubMed and SpringerLink for the research addressing the measurements of traction force using the keywords of cell traction force, biomechanics in Chinese and English, respectively. Repetitive articles were excluded, and 30 literatures were enrolled for analysis, including 1 Chinese and 29 English articles.RESULTS AND CONCLUSION: There are three kinds of measurements of traction force, such as silica gel membrane, traction force microscopy, and micromachined levers. The precise measurement of traction force contributes to further understand the cell-cell and cell-microenvironment mechanical interactions.

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