Objective To explore the automated identification and diameter measurement methods for inferior vena cava (IVC) based on clinical ultrasound images of IVC. Methods An automated identification and localization method based on topology and automatic tracking algorithm was proposed. Tracking algorithm was used for identifying and continuously locating to improve the efficiency and accuracy of measurement. Tests were conducted on 18 sets of ultrasound data collected from 18 patients in intensive care unit (ICU),with clinicians' measurements as the gold standard. Results The recognition accuracy of the automated method was 94.44％ (17/18),and the measurement error of IVC diameter was within the range of±1.96s (s was the standard deviation). The automated method could replace the manual method. Conclusion The proposed IVC automated identification and localization algorithm based on topology and automatic tracking algorithm has high recognition success rate and IVC diameter measurement accuracy. It can assist clinicians in identifying and locating IVC,so as to improve the accuracy of IVC measurement.

Humans ; Aged ; Acute Kidney Injury ; Risk Factors ; Creatinine

OBJECTIVE：To investigate the s ynergy between centralized drug volume-based purchasing （called“volume- based purchasing”for short ）and medical insurance negotiation policy. METHODS ：From the aspects of economic and social benefits ， the synergy of volume-based purchasing and medical insurance negotiation was analyzed by using the methods of literature analysis，policy interpretation and interview. The corresponding suggestions were put forward for the problems of the supply and use of drugs. RESULTS & CONCLUSIONS ：The synergy of volume-based purchasing and medical insurance negotiation in terms of economic benefits include medical insurance fund management optimization to improve fund utilization efficiency improvement ； medical insurance fund payment optimization to reduce transaction cost ；network promotion of medical security information platform to reduce the cost of information exchange. The synergy of volume-based purchasing and medical insurance negotiation in terms of social benefits includes relevant index assessment of drug quality evaluation to improve drug quality evaluation system ； medical service level improvement to form compound medical insurance payment mode under total budget management ；enterprise supervision driven by market to reduce the pressure of government supervision. The relevant departments should continue to strengthen the comprehensive management of medical institutions to reduce the phenomenon of irrational drug use ；strengthen policy convergence ，avoid the poor implementation of medical insurance drug adjustment policy ，so that the policy dividend of volume-based purchasing and medical insurance negotiation can benefit the people more through system reform ，optimal allocation of funds ，etc.

Objective: To assess the feasibility of HEAD-US scale in the clinical application of hemophilic arthropathy (HA) and propose an optimized ultrasound scoring system. Methods: From July 2015 to August 2017, 1 035 joints ultrasonographic examinations were performed in 91 patients. Melchiorre, HEAD-US (Hemophilic Early Arthropathy Detection with UltraSound) and HEAD-US-C (HEAD-US in China) scale scores were used respectively to analyze the results. The correlations between three ultrasound scales and Hemophilia Joint Health Scores (HJHS) were evaluated. The sensitivity differences of the above Ultrasonic scoring systems in evaluation of HA were compared. Results: All the 91 patients were male, with median age of 16 (4-55) years old, including 86 cases of hemophilia A and 5 cases hemophilia B. The median (P₂₅, P₇₅) of Melchiorre, HEAD-US and HEAD-US-C scores of 1 035 joints were 2(0,6), 1(0,5) and 2(0,6), respectively, and the correlation coefficients compared with HJHS was 0.747, 0.762 and 0.765 respectively, with statistical significance (P<0.001). The positive rates of Melchiorre, HEAD-US-C and HEAD-US scale score were 63.0% (95%CI 59.7%-65.9%), 59.5% (95%CI 56.5%-62.4%) and 56.6% (95%CI 53.6%-59.6%) respectively, and the difference was statistically significant (P<0.001). Even for 336 cases of asymptomatic joints, the positive rates of Melchiorre, HEAD-US-C and HEAD-US scale score were 25.0% (95%CI 20.6%-29.6%), 17.0% (95%CI 12.6%-21.1%) and 11.9% (95%CI 8.4%-15.7%) respectively, and the difference was statistically significant (P<0.001). There were significant changes (P<0.05) in the ultrasonographic score of HA before and after onset of hemorrhage in 107 joints of 40 patients. The difference in variation amplitude of HEAD-US-C scores and HEAD-US scores before and after joint bleeding was statistically significant (P<0.001). Conclusion Compared with Melchiorre, there were similar good correlations between HEAD-US, HEAD-US-C and HJHS. HEAD-US ultrasound scoring system is quick, convenient and simple to use. The optimized HEAD-US-C scale score is more sensitive than HEAD-US, especially for patients with HA who have subclinical state, which make up for insufficiency of sensitivity in HEAD-US scoring system

Objective: To explore the evaluation of joint injury by HEAD-US-C (Hemophilic Early Arthropathy Detection with UltraSound in China, HEAD-US-C) in patients with moderate or severe hemophilia A treated with prophylaxis vs on-demand. Methods: The patients from June 2015 to July 2017 with moderate or severe hemophilia A were examined by ultrasound imaging of the elbows, knees and ankles; Meanwhile the HEAD-US-C ultrasound assessment scale and hemophilia joint health score scale 2.1 (HJHS2.1) were used to score the joint status. The correlation between the HEAD-US-C and HJHS score was performed in prophylaxis group and on-demand group patients, respectively. Results: A total of 925 cases of joint ultrasonography were conducted in 70 patients with moderate or severe hemophilia A. Among patients with moderate hemophilia, the median (IQR) of HEAD-US-C score and HJHS score in on-demand group were significantly higher than those in the prophylaxis group[1 (0, 6) vs 0.5 (0, 3) , z=0.177, P=0.046],[2 (0, 4) vs 2 (0, 3) z=0.375, P=0.007], even though there was no significant difference of the median (IQR) number of annualized target joints bleeding episodes between on-demand and prophylaxis groups[1 (0, 7) vs 1 (0, 5) , z=1.271, P=0.137]. Unlike in moderate cases, on-demand treatment group had more annualized target joints bleeding episodes than prophylaxis group among patients with severe hemophilia[3 (0, 8) vs 2 (0, 8) , z=0.780 P=0.037]. The prophylaxis group compared favorably with on-demand therapy group in terms of HEAD-US-C score[1 (0, 6) vs 4 (0, 7) , z=2.189, P=0.008], and HJHS score[2 (0, 5) , 4 (1, 6) , z=3646, P<0.001]for the severe hemophilia patients. The positive correlation between HEAD-US-C score and HJHS score was identified (P<0.05) , whether on-demand treatment or prophylaxis groups. The correlation coefficient between HEAD-US-C score and HJHS score in on-demand treatment and prophylaxis groups were 0.739 (95% CI 0.708-0.708) , 0.865 (95% CI 0.848-0.848) respectively, and 95% CI didn’t overlap (P<0.05) , indicating that the correlation coefficient in prophylaxis group had stronger correlation than that in on-demand group. Conclusions Clinical effects of prophylaxis were significantly better than those of on-demand treatment in patients with moderate or se-vere haemophilia A. HEAD-US-C scoring system could effectively evaluate joints damage in hemophilia A patients treated with on-demand or prophylaxis, companied by significantly positive correlation with HJHS clinical evaluation system, and provided objective index for clinical effect assessment.

This study was aimed to search anti-platelet aggregation effectors from Gardenia jasminoides extract with the employment of platelet affinity extraction method coupled with HPLC, in order to provide pharmacological experi-mental evidences of the selected effectors to verify its feasibility. Under physiological conditions, washed rat platelets were added into G. jasminoides extract and then a mixture was gained. Consequently, some components from G. jas-minoides extract were combined to the platelets in the mixture while some were not owing to their special chemical structures and properties. Firstly, the uncombined components were washed off from the mixture. Secondly, the com-bined components in the leftover was washed down and collected, respectively, right after destroying the occupied platelets' structures. Thirdly, different collected eluents were analyzed, respectively, by HPLC established in the pre-vious work to search the effectors. Fourthly, pharmacological experiments were implemented for confirmation. The re-sults showed that dominant effective components from G. jasminoides extract acting on anti-platelet aggregation were identified as geniposide. Further evident was provided as well by pharmacological experiment that geniposide exhibit-ed significant inhibitory effect on anti-platelet aggregation in rats induced by ADP, rat tail collagen and thrombin(P< 0.01). It was concluded that the platelet affinity extraction-HPLC method proposed in this paper can be utilized to analyze the correlation of effectors from G. jasminoides extract and its pharmacological effects. Moreover, there are some correlations between screened chemical substances and their pharmacological effects.

OBJECTIVETo investigate the characteristics of ultrasonography in haemophilic arthropathy in knee joints.

METHODSThe knee joints (n=135) of 68 patients with haemophilia A (n=59) or haemophilia B (n=9) were consecutively evaluated with ultrasonography and scored according to MELCHIORRE ultrasound score. The correlations between ultrasound score and the number of knee joint bleeding episodes, age, and World Federation Haemophilic orthopedic (WFHO) score were studied.

RESULTS68 male patients with median age 20 (3-48) years old were enrolled in this study. The prevalences of hydrops articuli, fibrotic septa, synovial hypertrophy, synovial hypertrophy with angiogenesis, haemosiderin deposition were 39.2% (53/135), 3.0% (4/135), 77.0% (104/135), 49.6% (67/135), 37.8% (51/135), respectively; and the prevalences of cartilage damage, bone erosion, bone remodeling, osteophytes were 63.7% (86/135), 48.1% (65/135), 3.0% (4/135), 13.3% (18/135) respectively. The average ultrasound score was 5.21[95% CI (4.50-5.93)]. The ultrasound score of knees joints according to age 0-6, 7-18 and > 18 years old groups were 0.63[95% CI (0.15-1.10)], 2.88[95% CI (1.90-3.85)], 7.83[95% CI (7.07-8.60)], respectively; and the difference among groups was statistically significant (P<0.01). The significant difference of ultrasound score was not found among moderate, mild and severe haemophilia (F=0.90, P=0.914). A significant positive correlation between ultrasound and WFHO scores was demonstrated (r=0.745, P<0.01). The ultrasound score increased significantly with the increase of number of knee bleed Episodes (F=49.926, P<0.01).

CONCLUSIONThe main characteristics of ultrasonography of haemophilic arthropathy in knee joints were identified as followings: synovial hypertrophy, cartilage damage, bone erosion, hydrops articuli, and haemosiderin deposition. Ultrasonography was a fast, effective, safe, and available inspection method in assessment of haemophilic arthropathy.

Adolescent ; Adult ; Child ; Child, Preschool ; Hemophilia A ; complications ; Hemophilia B ; complications ; Humans ; Joint Diseases ; diagnostic imaging ; etiology ; Knee Joint ; diagnostic imaging ; Male ; Middle Aged ; Ultrasonography ; Young Adult

In order to study the underlying electrode-nerve functional mechanism, optimize the electrode design and guide the prosthesis application, we applied finite element method to analyze the spatial distribution of electric field generated by optic nerve electrical stimulation with spiral cuff electrode. A macroscopic cylindrical model of optic nerve was elaborated, taking into account of electrode contact configurations and possible variations of the thickness of cerebrospinal fluid (CSF). By building an appropriate mesh on this model and under some boundary conditions, the finite element method was applied to compute the 3D electric field generated by the electrode with finite element software COMSOL Multiphysics. The stimulation results indicated that, under the same conditions of stimulation, the longitudinal tripolar electrode structure could generate larger current density than that of biopolar electrode structure (located in the opposite of nerve trunk). However biopolar electrode structure requirs less leads, and is more easily implanted. By means of parametric sweep, the results suggest that, with the increase of the CSF thickness and a higher conductivity of CSF than those of other tissues, the distribution of electric field generated by electrodes is extended but scattered, and the diffuse current distribution makes nerve stimulation less effective.
Electric Stimulation ; Electrodes, Implanted ; Electromagnetic Fields ; Extracellular Space ; Finite Element Analysis ; Humans ; Optic Nerve ; cytology ; physiopathology ; Visual Prosthesis

ObjectiveOptic nerve stimulation with penetrating electrode.is a new method for developing visual prosthesis.A simulation system was developed with computer software MATLAB to investigate its mechanism.MethodsVolume conductor model of optic nerve and optic nerve fiber model were developed.With the stimulation of monopolar penetrating electrode,the excitation thresholds of fibers at different depth were calculated.The activating function and activation region were employed to characterize the external stimulation effect.The impact of different parameters on stimulation effects were explored by changing the fiber diameter and the stimulation pulse width.Results Excitation thresholds increased as well as the percentage of activated fibers with the increase of electrode-fiber distance.Excitation threshold of the same depth fiber decreased as the fiber diameter increased,and the longer the electrode-fiber distance was,the more significant the drop was.Excitation threshold of the same depth fiber decreased as the pulse width of monophasic rectangle wave increased.The excitation threshold of the fiber at the same depth hardly changed for pulse durations greater than 0.5 ms.ConclusionThe simulation results indicates that optical nerve stimulation can be realized with penetratingelectrode,and different stimulation parameters can produce different activation effects.The present results providetheoretical guidance for the design of experiments.

ObjectiveIn this paper a new application of LABVIEW in neural electrophysiological simulation was applied to simulate axonal excitability.MethodsA variety of axonal excitability of the squid giant axon was modeled with LABVIEW,including action potential threshold,refractoriness,temporal summation,anode break excitation,repetitive firing and conduction velocity.ResultsThe LABVIEW program accurately described the permeability changes of Na+ and K+ and their effects on the action potential,and the membrane excitability had been well predicted.ConclusionThe graphical programming language of LABVIEW allows the user to complete the programming by dragging and dropping icons and connecting wires,the users can quickly and easily construct their own biological research systems.