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BACKGROUND: Sand therapy has been shown to exhibit a positive effect on reducing femoral atherosclerosis and inhibiting thrombosis. OBJECTIVE: To investigate the effects of sand therapy on hemodynamic parameters of different stenosis models of femoral bifurcation through comparing the hemodynamic parameters and wall shear stress in four stenosis models before and after sand therapy. METHODS: The study protocol was performed in strict accordance with the relevant ethical requirements of School of Mechanical Engineering of Xinjiang University. Each participant provided written informed consent. Medical software Mimics10.01, reverse engineering software Geomagic Studio 2012 and three-dimensional CAD software UG8.5 were used to separate and optimize the CT data of a subject’s lower extremities and the geometric model of the femoral artery bifurcation was obtained. According to the classification criteria of vascular stenosis caused by femoral atherosclerotic plaque in the lower extremity, the degree of plaque stenosis on the side wall of the femoral bifurcation tube was set as 0% (normal), 15% (normal), 30% (mild) and 50% (moderate). Computational fluid dynamics method was used for numerical simulation. The Laminar flow model was selected for blood flow before sand therapy, and the standard turbulence model κ-ε was selected for blood flow after sand therapy. Blood flow velocity and wall shear stress were analyzed before and after sand therapy. RESULTS AND CONCLUSION: The maximum blood flow velocity after sand therapy was 0.35-0.45 m/s higher than that before sand therapy. After sand therapy, the wall shear stress at the stenosis was increased by 5-11 Pa compared with that before sand therapy, and the wall shear stress at 50% vascular stenosis rate model reached 41 Pa. These results suggest that the trend of atherosclerotic plaque enlargement is decreased after sand therapy, but patients with 50% (moderate) vascular stenosis have the risk of plaque rupture.
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Objective To study the effect of sand therapy on the hemodynamics of flexural femoral artery, and further reveal the therapeutic mechanism of sand therapy from the perspective of hemodynamics. Methods The three-dimensional finite element model of the curved femoral artery was established based on CT images of human aorta, and the data of heart rate, peak blood flow velocity and inner diameter of femoral artery measured by the experiment were used as initial conditions and boundary conditions to carry out finite element numerical simulation. The blood flow velocity, pressure and wall shear stress before and after sand therapy were analyzed and compared under fluid-solid coupling condition. Results Compared with treatment before sand therapy, the longitudinal velocity of the flexural segment of blood vessel increased significantly, with an increase of 22.76%. The secondary reflux velocity decreased significantly, with a relative decrease of 18.26%. The wall shear stress decreased by 2.01% after sand therapy. Conclusions Sand therapy had a significant effect on blood fluidity, by improving blood flow of femoral arteries, and preventing deposition of arterial platelets. The transverse flow phenomenon was obviously weakened after sand therapy, which could avoid the deposition of substances in blood and had a positive effect on the prevention of atherosclerosis, thrombosis and other vascular diseases.
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Objective To study the effect of sand therapy on the hemodynamics of flexural femoral artery, and further reveal the therapeutic mechanism of sand therapy from the perspective of hemodynamics. Methods The three-dimensional finite element model of the curved femoral artery was established based on CT images of human aorta, and the data of heart rate, peak blood flow velocity and inner diameter of femoral artery measured by the experiment were used as initial conditions and boundary conditions to carry out finite element numerical simulation. The blood flow velocity, pressure and wall shear stress before and after sand therapy were analyzed and compared under fluid-solid coupling condition. Results Compared with treatment before sand therapy, the longitudinal velocity of the flexural segment of blood vessel increased significantly, with an increase of 22.76%. The secondary reflux velocity decreased significantly, with a relative decrease of 18.26%. The wall shear stress decreased by 2.01% after sand therapy. Conclusions Sand therapy had a significant effect on blood fluidity, by improving blood flow of femoral arteries, and preventing deposition of arterial platelets. The transverse flow phenomenon was obviously weakened after sand therapy, which could avoid the deposition of substances in blood and had a positive effect on the prevention of atherosclerosis, thrombosis and other vascular diseases.
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Objective To investigate the effects of Uyghur indoor sand therapy on the hemodynamics of femoral artery bidirectional fluid-solid coupling,and to discuss the influence of Uyghur indoor sand therapy on the formation of atherosclerosis as well as on the rupture of blood vessels.Methods This study of indoor Uyghur sand therapy was conducted in young healthy volunteers.The heart rate,peak value of femoral artery blood flow velocity and inner diameter were determined,and the results were statistically analyzed.Three dimensional fluid-solid coupling model of human femoral artery was reconstructed.Taking the sine function as the initial condition,the non-steady field bidirectional fluid-solid coupling simulation was conducted by using Fluent software,and the effect of indoor Uyghur sand therapy on femoral artery wall shear stress as well as on yon Mises equivalent stress was evaluated.Results The average heart rates before and after indoor Uyghur sand therapy were (76.32±11.40) beats per minute and (92.69±16.09) beats per minute respectively,the difference was statistically significant (P＜0.05).The Renolds number of femoral artery before and after indoor Uyghur sand therapy was 1855.35 and 2518.4 respectively.The Uyghur sand therapy had more obvious influence on the increase of femoral artery wall shear stress and von Mises equivalent stress.Conclusion Uyghur sand therapy can increase Renolds number of femoral artery and improve the blood flow state of human femoral artery,but after the treatment the femoral artery blood flow pattern changed from laminar flow to turbulence flow,which may lead to the formation of hemangioma,therefore,for patients whose inner wall of blood vessel are thinner the sand-buried time,burying-sand thickness and temperature should be strictly controlled.Uyghur sand therapy can also increase wall shear stress,which plays a certain positive role in preventing atherosclerosis and thrombosis caused by thickening of the arterial wall.After Uyghur sand therapy,the von Mises equivalent stress is remarkably increased,which can increase the possibility of angiorrhexis at femoral artery bifurcation,thus,full attention should be paid to patients during the performance of Uyghur sand therapy.
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Objective To investigate the effects of sand therapy temperature on bone reconstruction and numerical study on the heat transfer.Methods CT scan imaging was performed respectively for four times(before and after OA model was set up,and after the first and second weeks during the sand therapy).Import the scan data to MIMICS software,and the changes of femoral bone mass layer were analyzed.After combining the muscle,femur,bone marrow and meshing,the established three-dimensional model of the STL format was introduced into the COMSOL software for heat transfer simulation and effect of stress on bone remodeling induced by temperature field.Results Changes of four CT scan data were analyzed.The soft bone volume was reduced,while the dense and hard bone volume were increased.Numerical simulation on the heat transfer showed the temperature distribution of the thigh and the femur.Conclusions The thermal stress produced by sand therapy temperature exert promoting effect on the femur bone remodeling.
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Objective To study effects from sand therapy of Uyghur medicine on hemodynamics in femoral artery branch and stress, so as to further discuss the functions and mechanisms of Uyghur sand therapy for treatment of femoral artery thrombosis formation. Methods Uyghur sand therapy was conducted on the subjects by indoor Uyghur sand therapy system. The peak values of blood flow velocity, inner diameter and resistance index (RI) of femoral artery before and after receiving Uyghur sand therapy were measured by the ultra-portable Doppler Diagnostic Ultrasound System for statistic analysis. Three-dimensional fluid-solid coupling model of femoral artery branch was reconstructed, and blood flow velocity, pressure, wall shear stress in the flow field as well as the equivalent stress, strain, total displacement on femoral artery wall were simulated and analyzed by the ANSYS Workbench. Results After receiving Uyghur sand therapy, the mean peak values of blood flow velocity and inner diameter of femoral artery increased by 32.43% and 2.68%, while the mean values of RI decreased by 4.88%, which showed it had the statistical difference(P0.05).Besides, the maximum values of blood flow velocity, pressure and wall shear stress increased by 29.91%，68.51%,46.54%,respectively, while the maximum values of equivalent stress, equivalent strain, total displacement on femoral artery wall increased by 65.85%，45.45%，44%, respectively, after receiving Uyghur sand therapy. Conclusions Uyghur sand therapy can increase blood flow velocity and decrease RI obviously，and help to expand the inner diameter of femoral artery to make blood circulation inside improved. With Uyghur sand therapy, the shear stress, blood flow velocity, pressure as well as the stress, strain, total displacement on femoral artery walls also increase, meanwhile，high pressure area on femoral artery branch reduces to some extent, which shows it plays a certain positive role in reducing atherosclerosis and thrombus formation inside femoral artery.
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Objective To investigate the mechanism of heat transfer process in sand therapy in Uyghur medicine. Methods A mathematical model was developed to describe the heat transfer process between human body and the sand during sand therapy. Temperature field was numerically simulated and analyzed based on this model. Results Temperature field in both human tissues and sand was calculated. The surface temperature of the sand and skin surface changed significantly at the beginning of the sand therapy, while sand temperature (5 cm deep) almost kept constant. The skin temperature dramatically increased at the beginning of the sand therapy and then slightly dropped. When sand was deeper than 10 cm, the thickness of sand would not influence the temperature field in human tissues during sand therapy. High initial temperature of sand might cause harmful skin burn. Threshold skin burn occurred if initial temperature of sand was higher than 64.6 ℃ and if the therapy lasted more than 30 minutes.Conclusion Temperature fieled in human tissues varies significantly with the initial temperature of sand, thickness of sand, and duration of therapy.
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Objective To study the effects of sand therapy on the ultrastructure of knee articular cartilage in rabbits with osteoarthritis ( OA ) and provide evidence of the effectiveness of sand therapy for OA in Uyghur medicine. Methods Models of knee OA were established by fixing with gypsum the right hind limbs of 28 rabbits. Of these, twenty-six rabbits were divided randomly into a free movement group and a free movement plus sand therapy group, and their left hind limbs were used as normal controls. Another two rabbits were used as specimens. The thirteen rabbits in the free movement group after the gypsum fixings were removed were allowed free movement every day for 20 days; the thirteen rabbits in the free movement plus sand therapy group had free movement plus sand therapy every day. The ultrastructure of each rabbit' s knee articular cartilage was observed using an electron microscope. Results Models of knee OA were established successfully. The changes in the ultrastructure of the knee articular cartilage revealed cell swelling, cell debris in part of the cartilage lacunae, and cartilage cells proliferating. The matrix of cartilage cells was thin, hetero chromatin concentrated on the margin and presented in a crescent form. Cell organellae decreased obviously, which was a sign of apoptosis. After the gypsum fixings were removed, the proliferation of cartilage cells gradually increased and rough endoplasmic reticula increased remarkably in the articular cartilages of the right hind knees of the free movement group. Cell pycnosis, disintegration and necrosis could be found in a few cells. The movement of the affected knees of the group treated with sand therapy plus free movement improved more significantly , and the changes in cartilage ultrastructure revealed more cell active proliferation, more rough endoplasmic reticu-lum, more cell surface processes and more matrix fibers. The morphology of cartilage cells in the control knees remained normal. Conclusion It is confirmed that Uyghur sand therapy combined with movement can improve the ultrastructure of knee articular cartilage in a rabbit model of OA.
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@#ObjectiveTo study the effects of the sand therapy of Uyghur Traditional Medicine on cytokines,such as interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), nitric oxide(NO) of the rabbit experimental knee osteoarthritis. Methods27 rabbits were injected papain into the joint space of right knee, and divided randomly into three groups. 15 d after the articular injection, the rabbits of group Ⅰ were treated with the sand therapy, the rabbits of group Ⅱ were treated with fenbid, and Ⅲ group accepted no treatment for the blank control.15 d after treatment, the serum and the douche fluid of the diseased joints were obtained to measure the level of IL-1β,TNF-α and NO. The synovium and the cartilage was observed histopathologically.ResultsCompare with group Ⅱ and Ⅲ, the pathological changes of cartilage and synovitis in group Ⅰ lighten significantly. Compare with groupⅢ,the level of IL-1β, TNF-α in articular douche fluid and NO in serum of group Ⅰ and Ⅱ decreased significantly. ConclusionThe sand therapy can decrease the level of cytokines in the focus joints, which may play a role of treatment in osteoarthritis.
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Objective To study the heating effect on skin of the therapeutic sand used in the Uyghur medicine. Methods We have continuously collected data of the dynamically changing surface body temperature during the course of sand therapy. Having applied the surface skin response equations, we calculated the situational effects on surface skin tissue by examining different temperature fields and time segments. All the data was collected by a 2 700 type multichannel data collection apparatus. Results It was found that, in the period of mid June to mid August every year, the air temperature of the sand therapy facility was 40?2.3℃ at the time 15∶00 to 18∶00 in the afternoon and the sand used as a medicinal poultice could be maintained at the temperature of 38?4.6℃ at the depth of 20 cm from the surface of the sand. During the process of sand therapy, the skin surface temperature rises rapidly, up to 39℃,but the skin surface temperature falls subsequently, as the heat stimulates perspiration and the cooling effect of evaporation takes place to 36?0.32℃. Two to three hours later, the surface skin temperature gets stable and maintained at 36?0.6℃. Conclusion When the sand temperature reached 43℃, it could not hurt the skin and tissue, because the body temperature could balance with sand temperature at an ideal temperature for the skin. The ideal time for sand therapy is during the period from June and August, at 15∶00~18∶00 every day. When the air temperature reaches 40?2.3℃, the sand temperature will be below 38?4.6℃. Under these conditions the human body should be buried under the sand at the depth of 20 cm for a period of one half to one hour to achieve therapeutic effects.