Numerical simulation is one of the most significant methods to predict the temperature distribution in high-intensity focused ultrasound (HIFU) therapy. In this study, the adopted numerical simulation was used based on a transcranial ultrasound therapy model taking a human skull as a reference. The approximation of the Westervelt formula and the Pennes bio-heat conduction equation were applied to the simulation of the transcranial temperature distribution. According to the temperature distribution and the Time Reversal theory, the position of the treatable focal region was corrected and the hot spot existing in the skull was eliminated. Furthermore, the influence of the exposure time, input power and the distance between transducer and skull on the temperature distribution was analyzed. The results showed that the position of the focal region could be corrected and the hot spot was eliminated using the Time Reversal theory without affecting the focus. The focal region above 60 degrees C could be formed at the superficial tis sue located from the skull of 20 mm using the hot spot elimination method and the volume of the focal region increases with the exposure time and the input power in a nonlinear form. When the same volume of the focal region was obtained, the more power was inputted, the less the exposure time was needed. Moreover, the volume of the focal region was influenced by the distance between the transducer and the skull.
Computer Simulation ; High-Intensity Focused Ultrasound Ablation ; Hot Temperature ; Humans ; Neoplasms ; therapy ; Skull

Objective To explore how neutrophil-lymphocyte ratio (NLR) is related with inflammation and atherosclerosis,and the role of NLR in hospitalization in maintenance hemodialysis (MHD) patients.Methods MHD patients treated in hemodialysis center of Sichuan Provincial People's Hospital from June till November 2013 were enrolled.Patients with severe infection,cardiovascular events and malignant carcinoma were excluded.NLR was determined from complete blood count differential.Clinical parameters such as serum albumin,lipids,intact parathormone,ferritin,C-reactive protein (CRP),25-(OH) vitamin D,interleukin-6 (IL-6) and alkaline phosphatase (ALP) were collected.Pulse wave velocity (PWV) and ankle-brachial index (ABI) were used to evaluate the arterial stiffness.Spearman analysis was used to evaluate the relationship between NLR and these parameters.All patients were divided into low NLR group (NLR≤3.25) and high NLR group (NLR ＞3.25) on the median NLR,and their differences in these indexes were analyzed.During the one-year follow-up,the reasons and rates of hospitalization and survival were analyzed.Results One hundred and thirteen MHD patients including 58 males and 55 females were enrolled with (69±49) dialysis age and (54± 15) average age.(1) The NLR was significantly correlated with whole blood count (WBC,r=0.538,P＜ 0.001),ABIL (r=0.201,P=0.033),ABIR (r=0.235,P=0.012) and total cholesterol (TC,r=-0.414,P＜ 0.001) and low-density lipoprotein cholesterol (LDL-C,r=-0.378,P ＜ 0.001).(2) Low NLR patients had increased TC,LDL-C and IL-6 as compare with high NLR patients,however decreased ABIL and ABIR (all P ＜ 0.05).(3) Forty one patients were hospitalized 63 times during the follow-up period.Annual hospitalization rate was 558/1000 and the mortality rate was 17.7/1000.(4)NLR in patients at least hospitalized once a year was significantly lower than in patients without hospitalization,while ALP was higher (all P ＜ 0.05).Compared with those in other patients,NLR and hemoglobin (Hb) were significantly lower in patients with hospitalization due to infection,while ALP was higher (all P ＜ 0.05).Conclusions NLR is related with WBC,ABI,TC and LDL-C in MHDpatients.Lower NLR may indicate high risk for cardiovascular,atherosclerosis and hospitalization,probably different form non-MHD patients,which needs more studies to verify.

Objective To explore the role of liver X receptor (LXR) agonist T0901317 on thrombomodulin (TM) expression in human glomerular endothelial cells and the possible mechanisms.Methods Different concentrations of T0901317 were used to stimulate human glomerular endothelial cells for different time,then LXRα,LXRβ expression were detected by using Western blotting analysis;the roles of T0901317 on TM mRNA and TM protein expression were observed by using real-time PCR,Western blotting and immunofluorescence assay.LXRα,LXRβ gene interference segment Si-hLXRα,Si -hLXRβ were transfected into human glomerular endothelial cells with the concentration of 100 nmol/L respectively,then the roles of Si-hLXRα,Si-hLXRβ on the TM protein and TM mRNA expression were assayed by Western blotting and real time PCR.Results Human glomerular endothelial cells expressed LXRα and LXRβ.Compared to the normal cells and DMSO group,T0901317 could significantly promote TM expression in human glomerular endothelial cells (P ＜ 0.05) and showed a time -and dose-dependent manner.TM expression in Si-hLXRα transfected group was significantly lower than that in the control group (P ＜ 0.05),while TM expression in Si-hLXRβ transfected group had no significant difference compared to the control group.Conclusions Human glomerular endothelial cells express LXRα and LXRβ.LXR agonist T0901317 promotes TM expression in human glomerular endothelial cells,which may be mainly through activating LXRa.

Objective We aim to evaluate the value of the current serum creatinine reference interval ( RI ) provided by Industry Standard WS /T 404.5 in clinical practice.Methods The first time serum creatinine levels and urinary albumin /creatinine ratio were obtained from 67 605 adult patients ( <60 years old) who were treated in the First Hospital of China Medical University between October 1, 2014 and September 30, 2015 in this cross-sectional study.Estimated glomerular filtration rate ( eGFR ) calculated by chronic kidney disease epidemiology collaboration (CKD-EPI) equation and urinary albumin /creatinine ratio (ACR) were used to evaluate the clinical practical significance of current and old serum creatinine RIs as the criteria.Results 4.3% of normal subjects based on current RI were showed decreased eGFR, 98% of abnormal subjects based on the current RI were founded to have decreased eGFR . 1378 subjects were evaluated as increased based on current RI but as normal based on old RI , and 93.5% of these subjects were showed decreased eGFR .In addition, ACR was measured in 26 cases, and 18 out of 26 cases (69.2%) were confirmed to have elevated ACR (≥30 mg/g) and proteinuria.On the other hand of analysis, screening positive rates of declined eGFR were 43.6% by old RI and 61.9% by current RI in the subjects with eGFR under 90 ml(min ×1.73 m 2 ), and the performance of the current RI was obviously improved(χ2 =212.648,P <0.001).Conclusions The current reference interval of serum creatinine is favorable for the detection of renal dysfunction in patients .It is recommended that the current reference interval can be applied in the clinical laboratories as early as possible .

Humans ; Inflammatory Bowel Diseases/drug therapy* ; Interleukin-6/therapeutic use*

Objective To design and test a device which is capable of accurately measuring and dynamically adjusting the axial pressure at the fracture end in real-time.Methods Upon completion of the design,the pressure measurement and adjustment device was implemented in a canine tibial fracture external fixation model.A pressure sensor was mounted at the fracture end,and the displayed values of the pressure sensor were used as the standard for comparison.The relationship between the displayed values of the measurement and adjustment device and the pressure sensor under identical conditions was examined.Results The device was utilized in external fixation models of tibial fractures in five beagles.A linear correlation was observed between the displayed values of the device and the pressure sensor at the fracture end.The measurement values from the device could be transformed into fracture end pressure through the application of coefficients,thereby facilitating accurate measurement and dynamic adjustment of the fracture end pressure.Conclusion The pressure measurement and adjustment device at the fracture end is easy to operate,enabling precise measurement and dynamic regulation of the pressure at the fracture end.It is well-suited for animal experiments aimed at investigating the impact of axial compression on fracture healing,demonstrating promising potential for experimental applications.

Objective The aim of this study was to evaluate the safety and efficacy of 135 cm Corsair microcatheter inpercutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO) with antegrade approach via radial artery. Methods From June 2010 to February 2014, a total of 81 patients with CTO lesions treated with 135cm Corsair microcatheter (Asahi Intec Co, Japan) and transradial antegrade approach was enrolled in this study. The success rate of CTO-PCI, the rate of Corsair microcatheter crossing the CTO lesions and the number of balloon catheters utilization were retrospectively analyzed. Unique complications related to the Corsair microcatheter were also documented. Results Success recanalization of CTO were achieved in 73 (90.1%) patients. Crossing the CTO body with Corsair microcatheter was found in 56(84.8%) patients. The number of balloon utilized after Corsair microcatheter crossing the CTO was much lower than that of patients who Corsair microcatheter failed to cross (1.3±0.6 per patient versus 2.8±1.2per patient, P < 0.05). The success recanalization rate of combined using Fielder XT guidewire with Corsair microcatheter was 51.5%. There was no complications related to Corsair microcatheter during the index procedure, no major adverse cardiac events during in-hospital clinical follow-up. Conclusions Corsair microcatheter was safe and effective in the recanalization for CTO with transradialantegrade approach. It can simplify the CTO-PCI procedure and reduce the number of balloon catheters.

Medical microbiology experiment is faced with many problems in online teaching. This study adopts the teaching mode of online live broadcast + operation video + virtual experiment, and make up the operation gap to some extent through operation video and virtual experiment. The mode of assessment is subjective thinking question (closely following the operation process) + experiment design + literature review (focusing on the key technology or new technology of clinical assessment that cannot be carried out due to the limitation of conditions in traditional experiments, such as mass spectrometry, fluorescence quantitative PCR, and G-test), and it is helpful to understand students' mastery of teaching objectives, and the ability of comprehensive application and innovative thinking. The student questionnaire shows that most students hold a positive attitude towards the online experimental teaching mode, and the quality of students' homework shows that most students have a good learning effect.

Objective:To investigate the predictors of the efficacy of extracorporeal shock wave lithotripsy (ESWL) in the treatment of ureteral calculi, and to evaluate the predictive value of the maximum ureteral wall thickness (UWT) in the treatment of ureteral calculi with ESWL.Methods:The clinical data of 138 patients with ureteral calculi treated with ESWL in the Second People's Hospital of Hefei from January 2020 to December 2020 were retrospectively analyzed. There were 91 males and 47 females. The age was (50.9±14.8) years old. The body mass index was (25.3±3.6) kg/m 2. The stones of 73 cases were located on the left side and 65 cases were on the right side. 70 cases had upper ureteral stones, 18 cases had middle ureteral stones, and 50 cases had lower ureteral stones. The median length of the stone was 8.5 (7.5, 10.5) mm. The CT value of the stone was 509 (343, 783) HU. The anteroposterior diameter of the renal pelvis was 12.0 (10.1, 16.0) mm, and UWT was (2.8 ± 0.8) mm. All patients underwent urinary non-contrast CT before lithotripsy, and the UWT of the stone bed was measured on the CT images. According to the stone removal situation 2 weeks after the operation, the patients were divided into a successful lithotripsy group and a failed lithotripsy group. Univariate analysis was used to compare the differences of various indicators between the two groups, and multivariate logistic regression was used to analyze the independent predictors of ESWL in the treatment of ureteral calculi for the indicators. The receiver operating characteristic (ROC) curve was used to calculate the area under the curve (AUC) of each independent predictor, and the cut-off value, sensitivity and specificity were analyzed. Results:All operations were successfully completed, and the success rate of the first-stage lithotripsy was 71.7% (99/138). The results of univariate analysis showed that the stone length diameter, stone CT value, anteroposterior diameter of renal pelvis, stone skin distance, and UWT were significantly different between the successful lithotripsy group and the failure group ( P<0.05). There was no significant difference in age, gender, body mass index, stone side and stone location ( P>0.05). The results of multivariate logistic analysis showed that stone length ( OR=1.393, P=0.015), stone CT value ( OR=1.002, P=0.043) and UWT ( OR=17.997, P<0.001) were all for the efficacy of ESWL in the treatment of ureteral stones. The ROC curve was used to compare the three independent predictors. The area under the UWT curve was the largest (AUC=0.898, P<0.001), followed by the length of the stone (AUC=0.744, P<0.001), and the CT value of the stone (AUC=0.672, P= 0.002). The cut-off value for UWT was 3.19 mm, which had a sensitivity of 91.9% and a specificity of 71.8% for predicting the success of ESWL lithotripsy. When dividing the patients into thin wall group (UWT ≤3.19 mm) and thick wall group (UWT>3.19 mm) according to the cut-off value, the success rates of one-stage lithotripsy in the two groups were 89.2% (91 / 102) and 22.2% (8/36), respectively ( P<0.05). Conclusions:UWT, calculus length and calculus CT value are independent predictors of the efficacy of ESWL in the treatment of ureteral calculi, and UWT has the best predictive value. When UWT≤3.19 mm, the success rate of ESWL in the treatment of ureteral calculi is higher.