Effects of Bilateral Knee Osteoarthritis on Dynamic Balance Ability of Ankle Strategy in Aged Women / 医用生物力学

Objective To investigate the effect of bilateral knee osteoarthritis (KOA) ondynamic balance ability of ankle strategy in aged women. Methods The dynamic balance ability tester was used to test the balance score, the rotation speed, the maximum rotation speed, and the percentage of the target ball's residence time in each area of KOA patients (KOA group)and the general elderly (control group), and a comparative analysis between groups was conducted. Results The balance score of KOA group was lower than that of control group; the dynamic balance control ability of KOA group in the horizontal direction was basically the same as that of control group, but the dynamic balance control ability of KOA group in the vertical direction was weaker than that of control group.Bilateral KOA reduced dynamic balance ability of ankle strategy in the aged women.It could not affect the left-right symmetric balance ability of the aged women, but it would reduce its forward-backward symmetrical balance ability. Conclusions Bilateral KOA aged women may be more likely to fall forward or backward, while not easy to fall laterally. For elderly female patients with bilateral KOA, methods such as strengthening ankle joint strength, proprioception and responsiveness can be used to prevent falls that may be caused by reduced dynamic balance ability, especially falls in the forward and backward directions.

Early Warning Model of Fall Risk for the Elderly Based on Gait Characteristics / 医用生物力学

Objective To construct an early warning model of fall risk for the elderly based on six kinds gait parameters. Methods A digital field was used to collect parameters from six kinds of gait for the elderly with or without the history of falls, and the binomial logistic regression analysis was used to establish a regression equation for predicting the fall risks in the elderly, and an early warning model was constructed. Results The regression equations constructed according to the parameters from six kinds of gait were statistically significant. The overall correct rate was predicted from high to low: walking forward with closed eyes (97.1%), walking backward with open eyes (92.9%), walking backward with closed eyes (88.6%), walking forward with open eyes (87.1%), turning head up and down with open eyes (85.7%), turning head left and right with open eyes(82.9%). The constructed early warning model for fall risk of the elderly mainly included five steps, namely, judgment, test, extraction, calculation and early warning, which was suitable for gait testing and evaluation of the elderly in the laboratory. Conclusions Parameters from six kinds of gait could predict the fall risk of the elderly. Among them, walking forward with closed eyes was best to predict the fall risk in the elderly. The established early warning model of fall risk for the elderly could be used to predict the fall risk of 65-75 year old people within one year, which could provide early warning based on the probability of falling, playing a positive effect on preventing falls in the elderly.

Lung nodule segmentation based on fuzzy c-means clustering and improved random walk algorithm / 生物医学工程学杂志

Accurate segmentation of pulmonary nodules is an important basis for doctors to determine lung cancer. Aiming at the problem of incorrect segmentation of pulmonary nodules, especially the problem that it is difficult to separate adhesive pulmonary nodules connected with chest wall or blood vessels, an improved random walk method is proposed to segment difficult pulmonary nodules accurately in this paper. The innovation of this paper is to introduce geodesic distance to redefine the weights in random walk combining the coordinates of the nodes and seed points in the image with the space distance. The improved algorithm is used to achieve the accurate segmentation of pulmonary nodules. The computed tomography (CT) images of 17 patients with different types of pulmonary nodules were selected for segmentation experiments. The experimental results are compared with the traditional random walk method and those of several literatures. Experiments show that the proposed method has good accuracy in the segmentation of pulmonary nodule, and the accuracy can reach more than 88% with segmentation time is less than 4 seconds. The results could be used to assist doctors in the diagnosis of benign and malignant pulmonary nodules and improve clinical efficiency.

Automatic multi-region segmentation of intracoronary optical coherence tomography images based on neutrosophic theory / 生物医学工程学杂志

Optical coherence tomography (OCT) has become a key technique in the diagnosis of coronary artery stenosis, which can identify plaques and vulnerable plaques in the image. Therefore, this technique is of great significance for the diagnosis of coronary heart disease. However, there is still a lack of automatic, multi-region, high-precision segmentation algorithms for coronary OCT images in the current research field. Therefore, this paper proposes a multi-zone, fully automated segmentation algorithm for coronary OCT images based on neutrosophic theory, which achieves high-precision segmentation of fibrous plaques and lipid regions. In this paper, the method of transforming OCT images into T in the area of neutrosophics is redefined based on the membership function, and the segmentation accuracy of fiber plaques is improved. For the segmentation of lipid regions, the algorithm adds homomorphic filter enhancement images, and uses OCT to transform OCT images into I in the field of neutrosophics, and further uses morphological methods to achieve high-precision segmentation. In this paper, 40 OCT images from 9 patients with typical plaques were analyzed and compared with the results of manual segmentation by doctors. Experiments show that the proposed algorithm avoids the over-segmentation and under-segmentation problems of the traditional neutrosophic theory method, and accurately segment the patch area. Therefore, the work of this paper can effectively improve the accuracy of segmentation of plaque for doctors, and assist clinicians in the diagnosis and treatment of coronary heart disease.

Effects of lidocaine on neutrophil apoptosis induced by tumor necrosis factor alpha / 中国组织工程研究

BACKGROUND: Lidocaine is deemed to can attenuate the inflammatory response, but the mechanisms are poorly understood. Nuclear factor-κB (NF-κB) is a key process of imflammatory response. OBJECTIVE: To determine the effect of lidocaine on activation and apoptosis of NF-κB in human neutrophiis in vitro. DESIGN, TIME AND SETTING: The controlled experiment was conducted at the Jiangsu Provincial Key Laboratory of Anesthesiology from October 2006 to February 2007. MATERIALS: Tumor necrosis factor (TNF)-α (0127:B8) was purchased from Sigma, USA. Peripheral blood samples were obtained from healthy donors after their informed consent. METHODS: Human neutrephilic granulocytes were assigned into five groups: ① saline control, ② TNF-α, ③ TNF-α+ lidocaine 1.0 mmol/L, ④ TNF-α+ lidocaine 2.0 mmol/L, and ⑤ TNF-α+ lidocaine 4.0 mmol/L groups. Incubation wasperformed for 3 hours.MAIN OUTCOME MEASURES: The effects of lidocaine on expression of NF- κB mRNA and I- κB mRNA in the cytosol extracts were analyzed by reverse transcription-polymerase chain reaction (RT-PCR), and content of p65 protein were analyzed by Western blot. Neutrophilic granulocyte apoptosis was detected on flow cytomatry after incubation 12 hours and 24 hours.RESULTS: The expression of NF- κB mRNA in the nuclear extracts was significantly decreased and I- κB mRNA in the cytosoI extracts was markedly increased in the lidocaine group. The expression of NF- κB was significantly better in the 2.0 mmol/L and 4.0 mmol/L lidocaine groups than in the 1.0 mmol/L lidocaine group (P< 0.05). No significant difference was detected between the 2.0 mmol/L lidocaine group and the 4.0 mmol/L lidocaine group (P0.05). Lidocaine could significantly inhibit peripheral blood neutrophilic granulocyte apoptosis induced by TNF-α (p < 0.05). The inhibitory effect was significantly better in the 4.0 mmol/L lidocaine group than in the 1.0 mmol/L lidocaine group (P < 0.05). CONCLUSION: Lidocaine (1.0, 2.0 and 4.0 mmol/L) can down-regulate the expressions of NF- κB subunit p65 mRNA and the content of p65 protein in human polymorphoneclear neutrophils, and can significant reverse the reduction of apoptosis induced by TNF-α.

The effects of two anesthetic regimens on energy metabolism and oxygen cost of breathing / 中华麻醉学杂志

Objective To compare the effects of combined general-epidural anesthesia (CGEA) and general anesthesia (GA) on energy metabolism and oxygen cost of breathing.Methods Forty patients (25 male, 15 female) aged 42-61 yr weighing 42-75 kg scheduled for elective upper abdominal surgery were randomly divided into 2 groups : group CGEA (Ⅰ, n = 20) and group GA (Ⅱ, n = 20) . The patients were premedicated with midazolam 0.05 mg?kg-1 and scopolamine 0.3 mg i.m. . In groupⅠepidural catheter was placed at T9-10 A. test dose of 4ml of 2 % lidocaine was given. When the height of block was confirmed general anesthesia was started. In both groups anesthesia was induced with etomidate 0.3 mg?kg-1 , fentanyl 8 ?g?kg-1 and tracheal intubation was facilitated with atracurium 0.8 mg?kg-1 . Anesthesia was maintained with propofol in both group and intermittent epidural lidocaine in CGEA group and intermittent i. v. boluses of fentanyl in GA group. Muscle relaxation was maintained with atracurium infusion at 8 ?g?kg-1 ? min-1 during operation. Oxygen consumption ( VO2 ), CO2 production (VCO2 ) , energy expenditure ( EE) and respiratory quotient (RQ) were measured before anesthesia, during and after operation using indirect calorimetry (Datex, Deltatrac MBM-200) . Postoperative oxygen cost of breathing (OCB) was calculated during spontaneous breathing and controlled ventilation. Results VO2 , VCO2 , EE were significantly lower and RQ was significantly higher during operation than those before anesthesia in both groups (P

EFFECTS OF FOLIC ACID ON APOPTOSIS OF NEURAL CELLS IN RATS WITH FOCAL CEREBRAL ISCHEMIA INJURY / 营养学报

Objective To investigate the effects of folic acid on apoptosis of neural cells after focal cerebral ischemia injury in rats and the mechanisms.Method Thirty two adult male Sprague-Dawley(SD) rats were randomly divided into sham operation group(SO),middle cerebral artery occlusion group(MCAO),MCAO+ low dose folic acid group(MCAO+FA-L) and MCAO+ high dose folic acid group(MCAO+FA-H).The model of middle cerebral artery occlusion(MCAO) was set up by using intraluminal filament method.The rats were sacrificed at D7 day after cerebral ischemia.The apoptotic rate of neural cells was examined by TUNEL test,and the expression of pERK1/2 protein was detected by Western blotting method,The MDA content and serum SOD and GSH-Px activities in rats were measured before and 28d after folic acid treatment and 7th day after ischemia.Results Compared with ischemia group,the apoptotic rate of neural cells and MDA content in both folic acid supplemented groups were decreased significantly(P