1.Design Method Analysis and Performance Comparison of Wall Filter for Ultrasound Color Flow Imaging.
Lutao WANG ; Jun XIAO ; Hua CHAI
Journal of Biomedical Engineering 2015;32(4):773-778
The successful suppression of clutter arising from stationary or slowly moving tissue is one of the key issues in medical ultrasound color blood imaging. Remaining clutter may cause bias in the mean blood frequency estimation and results in a potentially misleading description of blood-flow. In this paper, based on the principle of general wall-filter, the design process of three classes of filters, infinitely impulse response with projection initialization (Prj-IIR), polynomials regression (Pol-Reg), and eigen-based filters are previewed and analyzed. The performance of the filters was assessed by calculating the bias and variance of a mean blood velocity using a standard autocorrelation estimator. Simulation results show that the performance of Pol-Reg filter is similar to Prj-IIR filters. Both of them can offer accurate estimation of mean blood flow speed under steady clutter conditions, and the clutter rejection ability can be enhanced by increasing the ensemble size of Doppler vector. Eigen-based filters can effectively remove the non-stationary clutter component, and further improve the estimation accuracy for low speed blood flow signals. There is also no significant increase in computation complexity for eigen-based filters when the ensemble size is less than 10.
Blood Flow Velocity
;
Color
;
Humans
;
Signal Processing, Computer-Assisted
;
Ultrasonography
3.Effect of the dipeptide Arg-Gln on retinopathy of prematurity in mice
Ai-Yuan, WANG ; Jun, CHAI ; Xiao-Long, CHEN
International Eye Science 2008;8(3):442-444
·AIM: To investigate the effect of the dipeptide Arg-Glnon retinal neovascularization of retinopathy of prematurity(ROP) in the oxygen-induced retinopathy (OIR) animalmodel.·METHODS.- Forty-eight 7-day-old C57BL/6J mice were exposed to 750mL/L oxygen for 5 days and then to normal situation to produce the murine model of oxygen-induced retinopathy (OIR). All mice received twice daily intra- peritoneal injections of PBS or the dipeptide Arg-Gln(1.0, 3.0, 5.0g/kg per day), starting on postnatal day 12 and continuing till postnatal day 17. Experimental groups (36 mice, 12 in each group) received Arg-Gln, while the control group (12 mice) received PBS. All mice were executed at postnatal day 17. The changes of retinal vessels of mice were observed by ADPase histochemical technique and HE staining was used to count preretinal neovascular nuclei. RNA was isolated from retinas of 28 mice (7 in each group) selected at random and VEGF mRNA level of each group was measured by real-time RT-PCR.·RESULTS; Neovascularization reduced in retinas of the dipeptide Arg-Gln treated group in a dose-dependent manner. Compared with control group, experimental group had diminished non-perfusion area and neovascular tufts in retinal flatmount. The number of the endo-theliocyte nuclei of new vessels extending from retina to vitreous was significantly less in the eyes of the experimental group than in control group. Arg-Gln at 5g/kg per day reduced preretinal neovascularization by about 75% (P< 0.01). There was a significant reduction in VEGF mRNA at the 17th day in Arg-Gln treated group compared with control group(P<0.01).·CONCLUSION; Arg-Gln dramatically inhibits retinal angiogenesis in OIR and this effect is associated with a reduction in retinal VEGF mRNA level. It appears to be a safe way to prevent and treat some neovascular retinal diseases including retinopathy of prematurity.
5.Characterization of imipenem non-susceptible Pseudomonas aeruginosa isolates from patients without carbapenem treatment
Yihai GU ; Xiao ZHU ; Shenghui CUI ; Jun ZHANG ; Qingyuan ZHOU ; Jingyun LI ; Jia CHAI
Chinese Journal of Laboratory Medicine 2012;35(8):716-721
Objectives To investigate characterization of imipenem resistance among imipenem non susceptible Pseudomonas aeruginosa isolated from patients who treated without imipenem and explore risk factors of imipenem resistance.Methods From April,2006 to March,2008,a total of 37 non-susceptible to imipenem without imipenem therapy isolates were collected from affiliated 3201st Hospital of Medical College of Xi'an Jiaotong University.The minimum inhibition concentration (MIC) to 11 antimicrobial agents were determined by the broth dilution method.We also tested imipenem MIC combined with efflux pump inhibitor PAβN.PCR was performed to check for the presence of carbapenem-hydrolylzing MBL genes and oprD gene.The expression level of oprD2 and ampC were evaluated by qRT-PCR.Molecular typing was performed using PFGE.Results There is significant difference ( t =- 2.9004,P < 0.01 ) of the average number days of therapy between with two or more antibiotics in the 16 patients (20.0 ± 9.5 ) d and that with only one antibiotic in the other 21 patients ( 12.6 ± 4.4 ) d before imipenem-non-susceptible strains were isolated.In all 37 strains,32 strains showed resistance to more than three antibiotics.The MBL gene ( IMP-9 ) was only found in one strain,but its phenotype is negative,oprD2 gene from the 29 strains were found forward inserted by ISpa1328.Thirty-five isolated were considered to have no oprD expression.The patterns of the total DNA of 37 strains appeared six PFGE types.The 26 strains belonged to C2 PFGE type.In the presence of PAβN,all 37 strains increased sensitivity to meropenem.Conclusion Fluoroquinolones and cephalosporins treatment could play an important role in imipenem non-susceptible production in the research isolates.
6.Effects of isoflurane preconditioning on expression of TLR4 and MyD88 during focal cerebral ischemiareperfusion in rats
Zhibin XIAO ; Changjun GAO ; Xiaoxu TANG ; Zhen ZHANG ; Jun WANG ; Yuming ZHANG ; Wei CHAI ; Xude SUN
Chinese Journal of Anesthesiology 2010;30(9):1102-1104
Objectiye To investgate the effects of isoflurane preconditioning on expression of Toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88) during focal cerebral ischemia-reperfusion (IR) in rats. Methods Thirty male SD rats weighing 250-300 g were randomly divided into 3 groups ( n = 10 each):sham operation group (group S);focal cerebral IR group and isoflurane preconditioning group (group IP). The animals were anesthetized with intraperitoneal pentobarbital 40 mg/kg. In group IR and IP a nylon thread with rounded tip was inserted into right internal jugular vein and threaded cranially until resistance was met. Mid-cerebral artery was occluded (MCAO) for 2 h followed by 24 h reperfusion. In group IP the animals inhaled 2% isoflurane98 % O2 for 1 h once a day for 5 consecutive days at 24 h before MCAO. Neurologic function was assessed and scored and cerebral infarct volume was measured at 24 h of reperfusion. The animals were sacrificed at 24, 48 and 72 h of reperfusion respectively. The right ischemic frontal lobes were removed for determination of TLR4, MyD88and NF-κB expression by Western blot analysis. Results MCAO significantly worsened neurologic function. The neurologic function deficit scores were significantly increased and the TLR4, MyD88 and NF-κB expression were significantly up-regulated in group IR as compared with group S (P < 0.05). Isoflurane preconditioning significantly decreased cerebral infarct volumes and neurologic function deficit scores and down-regulated the expression of TLR4, MyD88 and NF-κB in group IP as compared with group IR ( P < 0.05). Conclusion Isoflurane preconditioning can reduce inflammatory response and focal cerebral IR injury by down-regulating the expression of TLR4and Myd88.
7.Effect of electro-acupuncture stimulation of Ximen (PC4) and Neiguan (PC6) on remifentanil-induced breakthrough pain following thoracal esophagectomy.
Yan-Hu, XIE ; Xiao-Qing, CHAI ; Yue-Lan, WANG ; Yan-Chun, GAO ; Jun, MA
Journal of Huazhong University of Science and Technology (Medical Sciences) 2014;34(4):569-74
The clinical analgesic effect of electro-acupuncture (EA) stimulation (EAS) on breakthrough pain induced by remifentanil in patients undergoing radical thoracic esophagectomy, and the mechanisms were assessed. Sixty patients (ASAIII) scheduled for elective radical esophagectomy were randomized into three groups: group A (control) receiving a general anesthesia only; group B (sham) given EA needles at PC4 (Ximen) and PC6 (Neiguan) but no stimulation; and group C (EAS) electrically given EAS of the ipsilateral PC4 and PC6 throughout the surgery. The EAS consisting of a disperse-dense wave with a low frequency of 2 Hz and a high frequency of 20 Hz, was performed 30 min prior to induction of general anesthesia and continued through the surgery. At the emergence, sufentanil infusion was given for postoperative analgesia with loading dose of 7.5 μg, followed by a continuous infusion of 2.25 μg/h. The patient self-administration of sufentanil was 0.75 μg with a lockout of 15 min as needed. Additional breakthrough pain was treated with dezocine (5 mg) intravenously at the patient's request. Blood samples were collected before (T1), 2 h (T2), 24 h (T3), and 48 h (T4) after operation to measure the plasma β-EP, PGE2, and 5-HT. The operative time, the total dose of sufentanil and the dose of self-administration, and the rescue doses of dezocine were recorded. Visual Analogue Scale (VAS) scores at 2, 12, 24 and 48 h postoperatively and the incidence of apnea and severe hypotension were recorded. The results showed that the gender, age, weight, operative time and remifentanil consumption were comparable among 3 groups. Patients in EAS group had the lowest VAS scores postoperatively among the three groups (P<0.05). The total dose of sufentanil was 115±6.0 μg in EAS group, significantly lower than that in control (134.3±5.9 μg) and sham (133.5±7.0 μg) groups. Similarly, the rescue dose of dezocine was the least in EAS group (P<0.05) among the three groups. Plasma β-EP levels in EAS group at T3 (176.90±45.73) and T4 (162.96±35.00 pg/mL) were significantly higher than those in control (132.33±36.75 and 128.79±41.24 pg/mL) and sham (136.56±45.80 and 129.85±36.14 pg/mL) groups, P<0.05 for all. EAS could decrease the release of PGE2. Plasma PGE2 levels in EAS group at T2 and T3 (41±5 and 40±5 pg/mL respectively) were significantly lower than those in control (64±5 and 62±7 pg/mL) and sham (66±6 and 62±6 pg/mL) groups. Plasma 5-HT levels in EAS group at T2 (133.66±40.85) and T3 (154.66±52.49 ng/mL) were significantly lower than those in control (168.33±56.94 and 225.28±82.03) and sham (164.54±47.53 and 217.74±76.45 ng/mL) groups. For intra-group comparison, plasma 5-HT and PGE2 levels in control and sham groups at T2 and T3, and β-EP in EAS group at T3 and T4 were significantly higher than those at T1 (P<0.05); PGE2 and 5-HT levels in EAS group showed no significant difference among the different time points (P>0.05). No apnea or severe hypotension was observed in any group. It was concluded that intraoperative ipsilateral EAS at PC4 and PC6 provides effective postoperative analgesia for patients undergoing radical esophagectomy with remifentanil anesthesia and significantly decrease requirement for parental narcotics. The underlying mechanism may be related to stimulation of the release of endogenous β-EP and inhibition of inflammatory mediators (5-HT and PGE2).
8.Evaluation of therapeutic effect and safety for clinical randomized and controlled trials of treatment of acne with acupuncture and moxibustion.
Bo LI ; Hua CHAI ; Yuan-hao DU ; Li XIAO ; Jun XIONG
Chinese Acupuncture & Moxibustion 2009;29(3):247-251
OBJECTIVETo evaluate the therapeutic effect and safety of acupuncture and moxibustion for treatment of acne, and to analyze the current situation of clinical studies at present.
METHODSRetrieve PubMed, Cochrane library, CBM databank, CNKI databank, etc., and collect the randomized and controlled trials of treatment of acne with acupuncture and moxibustion, and select clinical trials conforming with the enrolled criteria, and conduct evaluation of quality with Cochrane systematic manual 5.0, and RevMan 4.2.8 was used for statistical analysis.
RESULTSSeventeen papers, including 1,613 cases, conformed with the enrolled criteria. Seventeen studies adopted the cured rate as the evaluation index, Meta-analysis showed treatment of acne by acupuncture and moxibustion with routine western medicine as control, significant difference for inter-group comparison [combined RR (random efficacy model) = 2.96, 95% CI (1.63, 4.91), Z=4.08. P<0.0001]; comprehensive acupuncture and moxibustion therapy was controlled with single acupuncture moxibustion therapy, significant difference for inter-group comparison [combined RR (fixed efficacy model) = 2.51, 95% CI (1.76, 3.57), Z=5.11, P<0.00001].
CONCLUSIONAcupuncture-mox ibustion is safe and effective for treatment of acne, and it is possibly better than routine western medicine, and the comprehensive acupuncture-moxibustion therapy is better than single acupuncture-moxibustion therapy. The conclusion has not been determined yet, because lower quality of a part of literature enrolled.
Acne Vulgaris ; therapy ; Acupuncture Therapy ; Humans ; Meta-Analysis as Topic ; Moxibustion ; Randomized Controlled Trials as Topic
9.Biological characteristics of rat bone marrow mesenchymal stem cells transfected with hypoxta-inducible factor-1α gene
Yuming ZHANG ; Jun WANG ; Zhen ZHANG ; Miaomiao Lü ; Zhibin XIAO ; Changjun GAO ; Wei CHAI ; Lixian XU ; Xude SUN
Chinese Journal of Anesthesiology 2011;31(7):858-861
ObjectiveTo evaluate the biological characteristics of rat bone marrow mesenchymal stem cells (BMSCs) transfected with hypoxia-inducible factor-1α(HIF-1 α) gene.MethodsThe rat BMSCs of 3rd generation and the vector expressing HIF-1α gene (pcDNA3.1-HIF-1α) were provided by department of anesthesia,Tangdu Hospital,the 4th Military Medical University.BMSCs expressing HIF-1α gene (BMSCs-HIF-1α cells) were constructed by transfection of vector pcDNA3.1-HIF-1α into BMSCs by means of electroporation.Successful transfection of HIF-1α gene was confirmed by immuno-cytochemistry.Simple BMSCs and BMSCs-pcDNA3.1 cells were used as control cells.After being cultured in hypoxic condition HIF-1α expression was detected by Western blot analysis.Flow cytometry was used to determine the proportion of cells in G1,G2 and S phase and detect apoptosis.The proliferation index (PI) was calculated.The cell growth curve was described by MTT assay and the number of the 3 types of cells was recorded.ResultsA large number of deep blue granules were observed in the nuclei of BMSCs-HIF-1α cells using immuno-cytochemistry but no such granule was found in the two types of control cells.HIF-1α expression was significantly up-regulated and apoptosis rate (the number of apoptotic cella/the total number of cells examined) decreased in BMSC-HIF-1α cells compared with the control cells.The proportion of cells in S and G2 phase was significantly higher and the proportion of cells in G1 phase was significantly lower and PI higher in BMSCs-HIF-1α cells than in the control cells.The number of BMSCs-HIF-lα cells was significantly higher than the number of the two types of control cells at day 3-8 of culture.There was no significant difference in the above variables between BMSCs and BMSCs-pcDNA3.1 cells.ConclusionBMSCs-HIF-1α is successfully constructed by transfection of vector pcDNA3.1-HIF-1α gene into BMSCs by means of electroporation.
10.Clinical analysis of mandibular reconstructions using synthetic bones based on three-dimensional printing technology in 149 cases
Aung Mar ZIN ; Wen-qing HAN ; Xiao-jun CHEN ; Li LIN ; Yan ZHANG ; Hai-song XU ; Gang CHAI ;
Journal of Shanghai Jiaotong University(Medical Science) 2017;37(6):758-763
Objective-To assess the clinical value of the computer-assisted three-dimensional reconstruction technique design and evaluate the climcal experience of manufacture artificial bone precision to repair the mandibular defect.Methods· From 2001 to 2016,163 computer-assisted reconstruction surgeries had been performed in Craniofacial Department,Ninth People's Hospital,Shanghai Jiao Tong University School of Medicine.During six months followup,the measurement data was conducted and compared with three-dimensional CT result.Random measurement of the three key anatomical points pre-and post-operative carried out with statistical error was used to evaluate the accuracy of computer-assisted three-dimensional reconstruction in mandibular defects repairation and to investigate the clinical application value of the operation time and postoperative complication rate.Results· From July 2001 to July 2016,a total of 163 patients underwent computer-assisted three-dimensional reconstruction of artificial bone repair for mandibular defects;149 patients met the statistical criteria in which preoperative design and postoperative actual effect's average distance error (1.27±0.15) mm,operation time (2.5±1.2) h.Conclusion· Threedimensional design of artificial bone to repair the mandibular defect is a valuable technology,by relying on quantitative design and preoperative simulation to simplify the difficulty and improve the accuracy of surgery.The patients showed high satisfaction rate with low surgical complications and long-term efficacy.