1.Study on Content Dynamic Changes of Three Water-soluble Flavonoids in Isodon Lophanthoides
Ming GONG ; Yangzhi HUANG ; Haiming TANG
China Pharmacist 2015;(6):949-951,969
Objective:To establish an HPLC method for the simultaneous determination of viceninⅡ, isoschaftoside and schafto-side in Isodon lophanthoides, and analyze their content dynamic changes. Methods:The HPLC system consisted of a Phenomenex luna C18(250 mm ×4.6 mm, 5 μm)column and a solution system of methanol and 0.5% formic acid with gradient elution, the flow rate was 0. 8 ml·min-1 and the detection wavelength was 334 nm at the column temperature of 25℃and the injection volume was 10 μl. Results:The linear range of viceninⅡ, isoschaftoside and schaftoside was 0.130-3.110 μg(r =0.999 8), 0.180-4.540 μg(r =0.999 9) and 0.080-1.970 μg(r =0. 9999), respectively. The average recovery was 96.8% (RSD =1.9%), 99.2% (RSD =1. 6%) and 97. 1% (RSD=1. 6%) (n=6), respectively. The above three kinds of water-soluble flavonoids from seedling stage to significant accumulation, isoschaftoside and schaftoside reached the highest value in March and August, the content of VitexinⅡ in January and April tends to be stable, in May began to increase gradually, reached the maximum value in August, then began to de-crease. Conclusion:With the contents of water-soluble flavonoids as the indicators, the best harvest time of Isodon lophanthoides is March and August, and the quality of the medicinal materials harvested in August is the best.
2.Comparison of the Lower Limb Kinematics and Muscle Activation Between Asian Squat and Western Squat
Fanjia WANG ; Chenlei ZHOU ; Lina LUO ; Shangjun HUANG ; Wenxin NIU
Journal of Medical Biomechanics 2021;36(5):E705-E711
Objective To compare the differences in lower limb joint kinematics and muscle activation between Asian squat (AS) and Western squat (WS). Methods Eleven healthy adults were recruited to complete the biomechanical test of AS and WS. The 3D motion analysis system, force plates and surface electromyography (EMG) were used to collect kinematics, kinetics and muscle activation data of the subjects during two squats, and muscle force of the lower limb was also calculated by OpenSim. Results AS showed pelvis forward flexion, while WS showed pelvis backward extension at the time of peak knee flexion angle. Compared with the AS, a significant smaller hip flexion, larger knee flexion, larger hip abduction and hip rotation angles were found in WS at the time of peak knee flexion angle. Compared with AS, a significant greater peak force of soleus was found in WS during descent and ascent phases of squat. Additionally, a smaller peak force of anterior tibia was found in WS than that in AS during descent and ascent phases of the squat. No significant differences were found in other muscle peak force and the time of peak force between AS and WS. Conclusions The combined tibialis anterior activation and proximal joint flexion might be beneficial to stabilization during AS. The soleus muscle activation was significant in WS with heel lifting. The muscle activation pattern of proximal joint was similar between AS and WS. This study provides theoretical guidance for the design of clinical squat rehabilitation programs or the selection of squat training.
3.Force Transmission Mode of Foot Ankle in Children with Down’s Syndrome During Standing
Yaqi LI ; Shangjun HUANG ; Beihua ZHANG ; Weizhi HUANG ; Yan WANG ; Wenxin NIU ; Ming ZHANG
Journal of Medical Biomechanics 2022;37(1):E059-E065
Objective To explore the joint contact force, ligament tensile force and force transmission mode of foot internal structure in Down’s syndrome child (DSC) during standing. Methods The finite element models of foot were constructed based on CT image data from one DSC and one typically developing child (TDC). The models were validated by plantar pressure measurement during static standing. To simulate foot force during standing, the ground reaction force and the triceps surae force were applied as the loading condition. Contact pressure of the tibiotalar, talonavicular and calcaneocuboid joints, tensile force of the spring and plantar calcaneocuboid ligaments, and force transmission mode in transverse tarsal joints were calculated and analyzed. Results The finite element models of foot were validated to be reliable. Compared with the TDC, the DSC showed higher contact pressure at the tibiotalar joint and lower contact pressure at the talonavicular joint. The tensile force of spring and plantar calcaneocuboid ligaments of DSC was 10 times and 58 times of TDC, respectively. The forces transmitted through both mediate and lateral columns in DSC were lower than those in TDC. Conclusions Abnormal contact pressure of the tibiotalar joint, larger tensile force of midfoot ligaments and smaller force of the transverse tarsal joint were found in DSC during standing. The abnormal alteration of stress patterns in foot internal structure of DSC should be fully considered in clinical rehabilitation, so as to provide theoretical references for screening and making intervention plans for early rehabilitation, as well as designing individualized orthopedic insoles.
4.Biomechanical analysis of ankle-foot complex during a typical Tai Chi movement-Brush Knee and Twist Step.
Tongbo CHANG ; Kuan WANG ; Shangjun HUANG ; Lejun WANG ; Shengnian ZHANG ; Wenxin NIU ; Ming ZHANG
Journal of Biomedical Engineering 2021;38(1):97-104
The purpose of this study is to analyze the biomechanics of ankle cartilage and ligaments during a typical Tai Chi movement-Brush Knee and Twist Step (BKTS). The kinematic and kinetic data were acquired in one experienced male Tai Chi practitioner while performing BKTS and in normal walking. The measured parameters were used as loading and boundary conditions for further finite element analysis. This study showed that the contact stress of the ankle joint during BKTS was generally less than that during walking. However, the maximum tensile force of the anterior talofibular ligament, the calcaneofibular ligament and the posterior talofibular ligament during BKTS was 130 N, 169 N and 89 N, respectively, while it was only 57 N, 119 N and 48 N during walking. Therefore, patients with arthritis of the ankle can properly practice Tai Chi. Practitioners with sprained lateral ligaments of the ankle joint were suggested to properly reduce the ankle movement range during BKTS.
Ankle
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Ankle Joint
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Biomechanical Phenomena
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Humans
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Knee Joint
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Lateral Ligament, Ankle
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Male
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Tai Ji
5.Advance in Rhythmic Auditory Stimulation to Improve Walking Function in Patients with Hemiplegia after Stroke (review)
Weijia GU ; Xiaoming YU ; Leichao LIANG ; Yan XU ; Xubo WU ; Shangjun HUANG
Chinese Journal of Rehabilitation Theory and Practice 2018;24(12):1408-1412
Through providing rhythmic stimulation to movement center, rhythmic auditory stimulation (RAS) may encourage hemiplegic patients to adjust movement pattern and external rhythm in time to improve the walking function after stroke. As an emerging intervention to treat the hemiplegic patients after stroke, RAS could effectively improve temporospatial gait parameters (gait velocity, stride length, cadence, and symmetry, etc.), joint movement pattern (angle of pelvis anterior tilt, and peak angle of knee flexion in mid-swing, etc.) and balance, which may be related to rhythmic entrainment movement system and the theory of auditory-movement synchronization. Simultaneously, frequency and dosage of RAS and the patient's lesions all have effect on the outcome of intervention.