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find Author "YUAN Yi" 9 results
  • MECHANISM OF VASCULAR STROMAL FRACTION AT EARLY STAGE AFTER ASPIRATED FAT TRANSPLANTATION

    Objective To investigate the mechanism of vascular stromal fraction (SVF) at the early stage after aspirated fat transplantation. Methods Fat was harvested from 5 cases of women undergoing abdominal liposuction operation, and SVF was isolated. Aspirated fat with (group B) or without (group A) SVF was injected subcutaneously into the back of nude mice, and the grafts were harvested at 1, 3, 5, and 7 days. Graft wet weight was measured; and immunohistochemical method (CD31) was performed and the secretion of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were qnantified by Western blot assay. Results The wet weight of transplanted adipose tissue showed an increasing tendency in groups A and B with time, and no significant difference was found between groups A and B (P gt; 0.05). At 1 and 3 days after transplantation, no CD31 positive cells was seen in 2 groups; the CD31 positive cells of group B were significantly more than those of group A at 5 and 7 days (P lt; 0.05), and the CD31 positive cells at 7 days were significantly more than those at 5 days in 2 groups (P lt; 0.05). Western blot test showed that VEGF expression reached peak at 3 days , then decreased gradually; the expression of VEGF protein in group B was significantly higher than that in group A at 1, 3, and 5 days (P lt; 0.05). The expression of HGF protein in groups A and B remained at a high level within 5 days, but it tended to decrease at 7 days, which was significantly higher in group B than that in group A (P lt; 0.05). Conclusion SVF can enhance angiogenesis by secretion of growth factors at the early stage after aspirated fat transplantation.

    Release date:2016-08-31 04:07 Export PDF Favorites Scan
  • MECHANISM OF IMPROVED REVASCULARIZATION OF FREE FAT GRAFTING WITH ADIPOSE-DERIVED STEM CELLS

    Objective To review the mechanism of improved revascularization of free fat grafting with adipose-derived stem cells (ADSCs). Methods The literature related to the basic researches of ADSCs in free fat grafting and angiogenesis was reviewed. Results Angiogenesis is a sequence process in time and space which is regulated by various factors. ADSCs possess the capability of secreting many angiogenic growth factors and differentiating into various lineages.Conclusion ADSCs affect every process of angiogenesis with clear improved angiogenic effects, however, the mechanisms of angiogenic effects need the further researches.

    Release date:2016-08-31 05:45 Export PDF Favorites Scan
  • Modulation of motor responses and neural activities with transcranial ultrasound stimulation based on closed-loop control

    Closed-loop transcranial ultrasound stimulation technology is based on real-time feedback signals, and has the potential for precise regulation of neural activity. In this paper, firstly the local field potential (LFP) and electromyogram (EMG) signals of mice under different intensities of ultrasound stimulation were recorded, then the mathematical model of ultrasound intensity and mouse LFP peak/EMG mean was established offline based on the data, and the closed-loop control system of LFP peak and EMG mean based on PID neural network control algorithm was simulated and built to realize closed-loop control of LFP peak and EMG mean of mice. In addition, using the generalized minimum variance control algorithm, the closed-loop control of theta oscillation power was realized. There was no significant difference between the LFP peak, EMG mean and theta power under closed-loop ultrasound control and the given value, indicating a significant control effect on the LFP peak, EMG mean and theta power of mice. Transcranial ultrasound stimulation based on closed-loop control algorithms provides a direct tool for precise modulation of electrophysiological signals in mice.

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  • Study of neuronal spike-frequency adaptation with transcranial magneto-acoustical stimulation

    Transcranial magneto-acoustical stimulation (TMAS), utilizing focused ultrasound and a magnetostatic field to generate an electric current in tissue fluid to regulate the activities of neurons, has high spatial resolution and penetration depth. The neuronal spike-frequency adaptation plays an important role in the treatment of neural information. In this paper, we study the effects of ultrasonic intensity, magnetostatic field intensity and ultrasonic frequency on the neuronal spike-frequency adaptation based on the Ermentrout neuron model. The simulation results show that, the peak time interval becomes smaller, the interspike interval becomes shorter and the time of the firing of the neuron is shortened with the increasing of the magnetostatic field intensity. With the increase of the adaptive variables, the initial spike-frequency is shifted to the right with the magnetostatic field intensity, and the spike-frequency is linearly related to the increase of the magnetostatic field intensity in steady state. The simulation effect with change of the ultrasonic intensity is consistent with the change of magnetostatic field intensity. The change of the ultrasonic frequency has no effect on the neuronal spike-frequency adaptation. Under the different adaptive variables, with the increase of the adaptive variables, the initial spike-frequency amplitude decreased with the increasing of the ultrasonic frequency, and the spike-frequency is linearly related to the increase of the ultrasonic frequency in steady state. These results of the study can help us to reveal the mechanism of transcranial magneto-acoustical stimulation on the neuronal spike-frequency adaptation, and provide a theoretical basis for its application in the treatment of neurological disorders.

    Release date:2017-12-21 05:21 Export PDF Favorites Scan
  • Treatment of Day type Ⅱ pelvic crescent fracture by using percutaneous cannulated screw fixation technique

    ObjectiveTo evaluate the feasibility and effectiveness of percutaneous cannulated screw fixation for the treatment of Day type Ⅱ pelvic crescent fracture.MethodsThe clinical data of 14 patients with Day type Ⅱ pelvic crescent fractures underwent closed reduction and percutaneous cannulated screw fixation between January 2009 and July 2016 were retrospectively analysed. There were 9 males and 5 females, aged 17-65 years (mean, 38 years). The causes of injury included traffic accident in 8 cases, falling from height in 3 cases, bruise injury in 3 cases; all were closed fractures. According to Tile classification, there were 8 cases of type B, 6 cases of type C. There were 13 cases combined with fracture of the anterior pelvic ring, including 8 cases of superior and inferior ramus of pubis fracture, 1 case of superior ramus of pubis fracture with symphysis separation, and 4 cases of symphysis separation. The interval of injury and admission was 1- 72 hours (mean, 16 hours), and the interval of injury and operation was 3-8 days (mean, 5 days). After operation, the reduction of fracture was evaluated by the Matta evaluation criteria, the clinical function was assessed by Majeed function assessment.ResultsThe operation time was 35-95 minutes (mean, 55 minutes), cumulative C-arm fluoroscopy time was 3-8 minutes (mean, 5 minutes), no iatrogenic vascular injury and pelvic organ damage occurred. Postoperative X-ray films at 2 days indicated that 2 cases of vertical shift and 2 cases of mild rotation were not completely corrected. Postoperative CT examination at 3 days indicated that 2 pubic joint screws broke through the obturator bone cortex. None of the pubic ramus screws entered into the acetabulum, but a screw of superior pubic branch broke through the posterior cortical of superior pubic branch, a screw of posterior ilium column broke through the medial bone cortex of the ilium, and no clinical symptom was observed. One patient suffered from wound infection in the pubic symphysis, then healed after 2 weeks of wound drainage, the other wounds healed by first intention. According to Matta criterion for fracture reduction, the results were excellent in 9 cases, good in 4 cases, and fair in 1 case with an excellent and good rate of 92.9%. All patients were followed up 8-24 months (mean, 14 months). All fractures healed at 4 months and restored to the normal walking at 6 months after operation, 3 patients suffered from slight pain in the sacroiliac joints and slight claudication when they were tired or walked for a long time and unnecessary for special treatment. One patient felt pain in the back of the iliac spine when he was lying down. During the follow-up, no screw loosening or other internal fixation failure occurred. At last follow-up, according to Majeed functional evaluation criteria, the results were excellent in 7 cases, good in 5 cases, and fair in 2 cases with an excellent and good rate of 85.7%.ConclusionThe percutaneous cannulated screw fixation is a safe treatment for Day type Ⅱ pelvic crescent fracture, which has a reliable fixation and good effectiveness.

    Release date:2018-02-07 03:21 Export PDF Favorites Scan
  • Treatment of distal humerus fracture with unexposed ulnar nerve medial elbow incision and anatomical locking compression plate

    ObjectiveTo investigate the feasibility and effectiveness of unexposed ulnar nerve medial elbow incision, open reduction and internal fixation of anatomical locking compression plate (LCP) for distal humerus fractures.MethodsFourteen patients with distal humerus fracture were treated between January 2014 and June 2017. There were 5 males and 9 females, aged 18-85 years (mean, 65.5 years). The causes of injury included falling from height in 12 cases and traffic accident in 2 cases, all were closed fractures. Fractures were classified according to the AO/Association for the Study of Internal Fixation (AO/ASIF): 3 cases of type A2, 2 cases of type A3, 4 cases of type B2, 2 cases of type C1, 2 cases of type C2, and 1 case of type C3; without ulnar nerve damage. The time from injury to operation was 4-15 days, with an average of 7 days. The type B2 fractures were treated with unexposed ulnar nerve elbow medial incision and anatomic LCP internal fixation, the rest patients were all treated with unexposed ulnar nerve medial plus conventional lateral approach and bilateral LCP internal fixation.ResultsThe operation time was 50-140 minutes (mean, 80 minutes), and the intraoperative blood loss was 20-200 mL (mean, 70 mL). There was no blood vessels or nerve damage during operation. All incisions healed by first intension, and no incision infection occurred. All the 14 cases were followed up 9-24 months (mean, 13 months). X-ray films showed that all fractures healed within 4 months without complications such as nonunion and osteomyelitis. No ulnar nerve injury, cubitus varus deformity, and ossifying myositis occurred during follow-up. At last follow-up, the elbow function was assessed by Mayo Elbow Performance score (MEPS), the results were excellent in 8 cases, good in 4 cases, fair in 1 case, and poor in 1 case (type C3 fracture), with the excellent and good rate of 85.7%.ConclusionThe unexposed ulnar nerve medial elbow incision can be used effectively to reduct the fracture, and it is not prone to ulnar nerve injury. Combined with the lateral approach to treat the distal humerus fracture, which has the advantages of short operation time, few trauma, little bleeding, and reliable effectiveness.

    Release date:2019-05-06 04:46 Export PDF Favorites Scan
  • Data visualization of multiple linear regression analysis practiced by R Studio software

    ObjectiveTo provide method references for data visualization of multiple linear regression analysis.MethodsAfter importing data to R Studio, this paper conducted general descriptive statistics analysis, then constructed a linear model between independent variables and the target. After checking independence of observations, the normality of the target, and the linearity between variables, this paper estimated coefficients of independent variables, dealt with multicollinearity, tested significance of estimates and performed residual analysis to guarantee that the regression met its assumptions, and eventually used the fitted model for prediction.ResultsThe multiple linear regression analysis implemented by R Studio software had better visualization functions and easier operation than traditional R language software.ConclusionsR Studio software has good application value in realizing multiple linear regression analysis data visualization.

    Release date:2021-05-25 02:52 Export PDF Favorites Scan
  • Application of thumb blocking technique with ulnar Kirschner wire threading for Gartland type Ⅲ supracondylar humerus fractures in children

    Objective To explore the effectiveness of thumb blocking technique through closed reduction of ulnar Kirschner wire threading in the treatment of Gartland type Ⅲ supracondylar humerus fractures in children. MethodsThe clinical data of 58 children with Gartland type Ⅲ supracondylar humerus fractures treated with closed reduction of ulnar Kirschner wire threading by thumb blocking technique between January 2020 and May 2021 were retrospectively analyzed. There were 31 males and 27 females with an average age of 6.4 years ranging from 2 to 14 years. The causes of injury were falling in 47 cases and sports injury in 11 cases. The time from injury to operation ranged from 24.4 to 70.6 hours, with an average of 49.6 hours. The twitch of ring and little fingers was observed during operation, the injury of ulnar nerve was observed after operation, and the healing time of fracture was recorded. At last follow-up, the effectiveness was evaluated by Flynn elbow score, and the complications were observed. Results There was no twitch of the ring and little fingers when the Kirschner wire was inserted on the ulnar side during operation, and the ulnar nerve was not injured. All children were followed up 6-24 months, with an average of 12.9 months. One child had postoperative infection in the operation area, local skin redness and swelling, and purulent secretion exudation at the eye of the Kirschner wire, which was improved after intravenous infusion and regular dressing change in the outpatient department, and the Kirschner wire was removed after the initial healing of the fracture; 2 children had irritation at the end of the Kirchner wire, and recovered after oral antibiotics and dressing change in the outpatient department. There was no serious complication such as nonunion and malunion, and the fracture healing time ranged from 4 to 6 weeks, with an average of 4.2 weeks. At last follow-up, the effectiveness was evaluated by Flynn elbow score, which was excellent in 52 cases, good in 4 cases, and fair in 2 cases, and the excellent and good rate was 96.6%. ConclusionThe treatment of Gartland type Ⅲ supracondylar humerus fractures in children by closed reduction and ulnar Kirschner wire fixation assisted with thumb blocking technique is safe and stable, and will not cause iatrogenic ulnar nerve injury.

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  • The application of Bayesian quantile regression in analysis of clinical medicine data and the R Studio practice

    ObjectiveTo combine specific examples and R Studio language code, to apply the Bayesian quantile regression method in the analysis of clinical medicine data, and show the advantages of Bayesian quantile regression method, so as to provide references for improving the accuracy of medical research. Methods The clinical data of 250 patients with knee osteoarthritis from the capital special research on the application of clinical characteristics project were used. A Bayesian quantile regression model based on data set was constructed to explore the relationship between the level of serum IgG and the age of the patients. Results The Monte Carlo algorithm converge can judge the efficiency of parameter estimation based on Gibbs sampling which was used to draw samples from the posterior distribution of parameters in Bayesian quantile regression. By generating the parameter into the regression formula, we can obtain the regression under different quantiles: Y1=−6.022 063 47+2.026 913 73X−0.015 077 69X2……Y5=24.610 542 414−0.395 059 497X+0.004 205 064X2. It can be found that the serum level of IgG was obviously increased with age. Conclusion Bayesian quantile regression parameter estimation results are accurate and highly credible, and reliable parameter information can be obtained even under small sample conditions. It has great advantages in the research of clinical medicine data and has certain promotional value.

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