1.Rapid femur modeling method based on statistical shape model.
Zhiwei ZHANG ; Zhenxian CHEN ; Zhifeng ZHANG ; Caimei WANG ; Zhongmin JIN
Journal of Biomedical Engineering 2022;39(5):862-869
The geometric bone model of patients is an important basis for individualized biomechanical modeling and analysis, formulation of surgical planning, design of surgical guide plate, and customization of artificial joint. In this study, a rapid three-dimensional (3D) reconstruction method based on statistical shape model was proposed for femur. Combined with the patient plain X-ray film data, rapid 3D modeling of individualized patient femur geometry was realized. The average error of 3D reconstruction was 1.597-1.842 mm, and the root mean square error was 1.453-2.341 mm. The average errors of femoral head diameter, cervical shaft angle, offset distance and anteversion angle of the reconstructed model were 0.597 mm, 1.163°, 1.389 mm and 1.354°, respectively. Compared with traditional modeling methods, the new method could achieve rapid 3D reconstruction of femur more accurately in a shorter time. This paper provides a new technology for rapid 3D modeling of bone geometry, which is helpful to promote rapid biomechanical analysis for patients, and provides a new idea for the selection of orthopedic implants and the rapid research and development of customized implants.
Humans
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Imaging, Three-Dimensional/methods*
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Tomography, X-Ray Computed/methods*
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Femur/surgery*
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Femur Head
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Lower Extremity
2.Application of nanocellulose in flexible sensors.
Peng SUN ; Yunyi DU ; Xubo YUAN ; Xin HOU ; Jin ZHAO
Journal of Biomedical Engineering 2022;39(1):185-191
The shortage of medical resources promotes medical treatment reform, and smart healthcare is a promising strategy to solve this problem. With the development of Internet, real-time health status is expected to be monitored at home by using flexible healthcare systems, which puts forward new demands on flexible substrates for sensors. Currently, the flexible substrates are mainly traditional petroleum-based polymers, which are not renewable. As a natural polymer, cellulose, owing to its wide range of sources, convenient processing, biodegradability and so on, is an ideal alternative. In this review, the application progress of nanocellulose in flexible sensors is summarized. The structure and the modification methods of cellulose and nanocellulose are introduced at first, and then the application of nanocellulose flexible sensors in real-time medical monitoring is summarized. Finally, the advantages and future challenges of nanocellulose in the field of flexible sensors are discussed.
Cellulose/chemistry*
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Hydrogels/chemistry*
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Polymers
4.Factors Influencing Sleep of Elderly Women.
Journal of Korean Academy of Nursing 2010;40(1):119-126
PURPOSE: The study was done to identify factors influencing the sleep of elderly women. METHODS: Data were collected by questionnaires from 203 elderly women in Seoul and Gyeong-gi province. Measures were physical health state, family support, life satisfaction, sleep, depression, and quality of life. Data were analyzed using Pearson correlation coefficients, t-test, ANOVA, and stepwise multiple regression with SPSS/WIN 13.0 version. RESULTS: The mean score for sleep for elderly women was 39.04. Sleep for elderly women according to religion, education level, spouses, and monthly income showed significant differences. Sleep for elderly women showed significantly positive correlations to physical health state, family support, life satisfaction, and quality of life. The significant factors influencing sleep of elderly women were physical health state, family support, depression, and quality of life, which explained about 70.4% of the variance. The strongest factors influencing the sleep was physical health state. CONCLUSION: The results suggest that in developing nursing interventions and practice for sleep pattern of elderly women spouses and family support should be considered.
Activities of Daily Living
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Aged
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Aged, 80 and over
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Depression
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Family Relations
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Female
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Health Status
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Humans
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Quality of Life
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*Sleep
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Women/*psychology
5.Discussion: Effects of fresh mineralized dentin and cementum on socket healing: a preliminary study in dogs.
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2015;41(3):124-124
No abstract available.
Animals
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Dental Cementum*
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Dentin*
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Dogs*
6. Protective effect of Ento-I plastic against cerebral ischemia-reperfusion injury in rats
Journal of International Pharmaceutical Research 2016;43(3):504-528
Objective To research the protective effect of Ento-I against cerebral ischemia-reperfusion injury in rats, and to evaluate its analgesic and anticoagulating effects in mice. Methods The ischemic model was established with line embolism to block the middle cerebral artery of male rats. The 56 rats were randomly assigned into 7 groups of sham-operation, blank-matrix, normal saline, Ento-I plastic of 3 doses (6.67, 3.33, 1.67 mg/kg), and ozagrel sodium (8.3 mg/kg, ip). The effect of Ento-I plastic on anti-cerebral ischemia was measured by nervous function scores and the areas of cerebral infarction were determined by TTC staining for the calculation of cerebral infarction rates. The analgesic effect of Ento-I plastic was determined with acetic acid-induced twisting experiment. Sixty KM mice were randomly allocated into blank-matrix, aspirin, aspirin-plastic, and Ento-I plastic of 3 doses (5, 10 and 20 mg/kg), the number of mouse twisting were recorded right after intraperitoneal injection of 0.7% acetic acid solution at the time of 1 h after the last administration. Moreover, the anticoagulant activity of Ento-I plastic was tested by glass capillary method. Results The results of acetic acid-induced twisting experiment displayed that Ento-I plastic of all 3 dose groups (5, 10 and 20 mg/kg) could significantly reduce the number of body torsion and increase the inhibitory rates of twisting, compared with that of blank matrix group (the inhibitory rates of twisting for 3 dose groups were 21.79%, 48.89%, and 56.15%, respectively), with dose-response manner. According to the results of glass capillary test, the clotting time of mouse blood could be significantly prolonged by mid- (10 mg/ kg) and low-dose (5 mg/kg) of Ento-I plastic with corresponding clotting time of (155.20±54.19) s and (155.80±73.84) s, compared with normal saline group at (92.10±24.61) and blank-matrix group at (80.40±48.09, P<0.05). The experiment results of the isch emia-reperfusion injury by line embolism method in rats exhibited that Ento-I plastic in mid-dose (3.33 mg/kg) could significantly re duce the neurological scores after 24 h of reperfusion injury, from (2.33±0.52) of normal saline group to (1.00±0.00) of mid-dose group (P<0.01). The results from TTC staining revealed that the cerebral infarction rates of normal saline group and blank- matrix group were (24.89±7.24) % and (27.72±7.89)%, respectively, whereas those of 6.67 mg/kg and 3.33 mg/kg group of Ento-I plastic were (14.01±2.65) % and (14.73±4.94)%, respectively. Compared to the 2 negative-control groups, both the high- and mid-dose of Ento-I plastic could significantly reduce the cerebral infarction rates after ischemic reperfusion injury in rats (P<0.01). Conclusion Ento-I plastic demonstrates strong analgesic and anticoagulant effects, and could substantially reduce the neurological scores and reduce cerebral infarction rates for ischemia-reperfusion injured rats. These are likely to be the mechanism of action for Ento-I plastic realizing its anti-cerebral ischemia effect.
7.Musculoskeletal multibody dynamics investigation for the different medial-lateral installation position of the femoral component in unicompartmental knee arthroplasty.
Jiaxuan REN ; Zhenxian CHEN ; Jing ZHANG ; Yongchang GAO ; Feng QIAO ; Zhongmin JIN
Journal of Biomedical Engineering 2023;40(3):508-514
The surgical installation accuracy of the components in unicompartmental knee arthroplasty (UKA) is an important factor affecting the joint function and the implant life. Taking the ratio of the medial-lateral position of the femoral component relative to the tibial insert (a/A) as a parameter, and considering nine installation conditions of the femoral component, this study established the musculoskeletal multibody dynamics models of UKA to simulate the patients' walking gait, and investigated the influences of the medial-lateral installation positions of the femoral component in UKA on the contact force, joint motion and ligament force of the knee joint. The results showed that, with the increase of a/A ratio, the medial contact force of the UKA implant was decreased and the lateral contact force of the cartilage was increased; the varus rotation, external rotation and posterior translation of the knee joint were increased; and the anterior cruciate ligament force, posterior cruciate ligament force and medial collateral ligament force were decreased. The medial-lateral installation positions of the femoral component in UKA had little effect on knee flexion-extension movement and lateral collateral ligament force. When the a/A ratio was less than or equalled to 0.375, the femoral component collided with the tibia. In order to prevent the overload on the medial implant and lateral cartilage, the excessive ligament force, and the collision between the femoral component and the tibia, it is suggested that the a/A ratio should be controlled within the range of 0.427-0.688 when the femoral component is installed in UKA. This study provides a reference for the accurate installation of the femoral component in UKA.
Humans
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Arthroplasty, Replacement, Knee
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Knee Joint/surgery*
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Knee Prosthesis
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Gait
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Rotation
8.Musculoskeletal multibody dynamics investigation of posterior-stabilized total knee prosthesis.
Zhenxian CHEN ; Zhifeng ZHANG ; Yongchang GAO ; Jing ZHANG ; Lei GUO ; Zhongmin JIN
Journal of Biomedical Engineering 2022;39(4):651-659
Posterior-stabilized total knee prostheses have been widely used in orthopedic clinical treatment of knee osteoarthritis, but the patients and surgeons are still troubled by the complications, for example severe wear and fracture of the post, as well as prosthetic loosening. Understanding the in vivo biomechanics of knee prostheses will aid in the decrease of postoperative prosthetic revision and patient dissatisfaction. Therefore, six different designs of posterior-stabilized total knee prostheses were used to establish the musculoskeletal multibody dynamics models of total knee arthroplasty respectively, and the biomechanical differences of six posterior-stabilized total knee prostheses were investigated under three simulated physiological activities: walking, right turn and squatting. The results showed that the post contact forces of PFC Sigma and Scorpio NGR prostheses were larger during walking, turning right, and squatting, which may increase the risk of the fracture and wear as well as the early loosening. The post design of Gemini SL prosthesis was more conductive to the knee internal-external rotation and avoided the edge contact and wear. The lower conformity design in sagittal plane and the later post-cam engagement resulted in the larger anterior-posterior translation. This study provides a theoretical support for guiding surgeon selection, improving posterior-stabilized prosthetic design and reducing the prosthetic failure.
Arthroplasty, Replacement, Knee/methods*
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Biomechanical Phenomena
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Humans
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Knee Joint/surgery*
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Knee Prosthesis
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Prosthesis Design
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Range of Motion, Articular/physiology*
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Tibia/surgery*
9.Research progress of effect of Tai Chi on cognitive function in the elderly based on neuroelectrophysiological techniques and brain imaging techniques.
Chen XUE ; Yuxi LI ; Dongling ZHONG ; Juan LI ; Zhong ZHENG ; Rongjiang JIN
Journal of Biomedical Engineering 2022;39(4):826-832
With the increasing prominence of population aging, the cognitive decline of the elderly has gradually become a hotspot of clinical research. As a traditional rehabilitation exercise, Tai Chi has been proved to have a positive effect on improving cognitive function and delaying cognitive decline in the elderly. However, the related brain function mechanism is still unclear. In this paper, we collected studies which observed the changes of Tai Chi on brain regions related to cognitive function in the elderly using magnetic resonance imaging (MRI), electroencephalogram (EEG) and functional near-infrared spectroscopy (fNIRS). We summarized relevant studies from perspective of structural and functional changes in the brain. The results showed that Tai Chi may delay and improve cognitive decline in the elderly by reshaping the structure and function of brain regions related to cognitive function such as memory, attention and execution. The effect of Tai Chi for cognitive function may be associated with positive regulation of cardiovascular function, emotion and meditation level of the elderly. In addition, the improvement of cognitive function further enhances the balance of the elderly. We also found that practice time, frequency and intensity of Tai Chi could be factors influencing the improvement of cognitive function and brain function in the elderly.
Aged
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Attention
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Brain/physiology*
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Cognition
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Humans
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Neuroimaging
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Tai Ji/psychology*
10.Effect of ventilation mode on pulmonary complications after thoracoscopic lung resection: A retrospective cohort study
Liang JIN ; Hong YU ; Wenjie MAO ; Qirong SUN ; Wei TIAN ; Hai YU
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2022;29(02):211-218
Objective To evaluate the association between pressure-controlled ventilation-volume guaranteed (PCV-VG) mode and volume-controlled ventilation (VCV) mode on postoperative pulmonary complications (PPCs) in patients undergoing thoracoscopic lung resection. Methods A retrospective cohort analysis of 329 patients undergoing elective thoracoscopic lung resection in West China Hospital of Sichuan University between September 2020 and March 2021 was conducted, including 213 females and 116 males, aged 53.6±11.3 years. American Society of Anesthesiologists (ASA) grade wasⅠ-Ⅲ. The patients who received lung-protective ventilation strategy during anesthesia were divided into a PCV-VG group (n=165) and a VCV group (n=164) according to intraoperative ventilation mode. Primary outcome was the incidence of PPCs during hospitalization. Results A total of 73 (22.2%) patients developed PPCs during hospitalization. The PPCs incidence of PCV-VG and VCV was 21.8% and 22.6%, respectively (RR=0.985, 95%CI 0.569-1.611, P=0.871). Multivariate logistic regression analysis showed that there was no statistical difference in the incidence of PPCs between PCV-VG and VCV mode during hospitalization (OR=0.846, 95%CI 0.487-1.470, P=0.553). Conclusion Among patients undergoing thoracoscopic lung resection, intraoperative ventilation mode (PCV-VG or VCV) is not associated with the risk of PPCs during hospitalization.