Attenuation of histone H4 lysine 16 acetylation (H4K16ac) elicits a neuroprotection against ischemic stroke by alleviating the autophagic/lysosomal dysfunction in neurons at the penumbra.

A modest autophagy benefits neuroprotection while an excessive autophagy leads to neuronal death after cerebral ischemia, but what governs an appropriate autophagy remains to be understood. Studies indicated that acetylation of histone H4 at lysine16 (H4K16ac) strongly modulated autophagic/lysosomal signaling pathway. Thus, this study was to investigate whether the autophagic neuronal injury could be alleviated by amending H4K16ac level after ischemic stroke. A rat model of middle cerebral artery occlusion (MCAO)/reperfusion was prepared to investigate dynamic variations between H4K16ac and autophagy at the penumbra. The results illustrated that the significantly elevated H4K16ac was coupled with dramatically promoted autophagic activity at 4 h after the insult, suggesting H4K16ac tightly controlled autophagic signaling. After that, H4K16ac level was altered by pretreatment with trichostatin A (TSA, a H4K16ac facilitator) and MG149 (a H4K16ac inhibitor), respectively. Four hours after MCAO/reperfusion, the penumbral tissues were obtained to detect the key proteins in autophagic/lysosomal pathway by western blot and immunofluorescence, respectively. Meanwhile, the infarct volume, neurological deficits, and neuron survival were assessed to evaluate the neurological outcomes. The results showed that TSA-promoted H4K16ac led to an excessively up-regulated autophagy resulting in autophagic/lysosomal dysfunction, as indicated by the accumulated autophagic substrates and exacerbated lysosomal inefficiency in neurons. By contrast, MG149-depressed H4K16ac significantly down-regulated autophagic activity and thereby restored the impaired autophagic flux. Consequently, the neurological injury was markedly alleviated in MCAO + MG149 group, compared with that in MCAO group. Our study suggests that the H4K16ac attenuation elicits neuroprotection against ischemic stroke by ameliorating autophagic/lysosomal dysfunction in neurons.

Risk factors for urinary tract infection in patients with urolithiasis-primary report of a single center cohort.

BACKGROUND: Urinary tract infection (UTI) is very common in patients with urolithiasis, which makes the treatment of urolithiasis complicated, even dangerous. The objective of this study was to determine the risk factors for UTI in patients with urolithiasis. METHODS: Eight hundred six patients with urolithiasis were retrospectively evaluated in the fourth affiliated hospital of China Medical University. All patients admitted to the study were divided into either a UTI infection group or a non-infection group. Sex, age, smoking, stone shape, alcohol consumption, position of stones, and presence of obstruction were used as exposure factors for the cross-sectional study. RESULTS: One hundred seventy-eight patients (22.0%) had UTI. Through a urine culture test, gram-negative bacilli were the most common pathogen, followed by gram-positive bacilli and fungi. CONCLUSIONS: Sex, age, obstruction, stone shape, and multiple sites of stones could be considered the independent factors for UTI in patients with urolithiasis; smoking and drinking had no statistically significant correlation with the condition. Gram-negative bacilli are the most common pathogen in UTI in patients with urolithiasis.

Effect of Low Rabll Expression on the Proliferation and Invasion of Human Bladder Cancer Cells / 中国医科大学学报

Objective To investigate the effect of inhibition of Rabll expression on the proliferation and invasion of human bladder cancer cell line T24. Methods T24 cells were transfected with Rabll siRNA, and RNA interference efficiency was determined by performing Western blotting. The effect of inhibition of Rabll expression on cell proliferation, cell cycle progression, and cell invasion was analyzed by performing CCK8, cell cycle detection, and Matrigel invasion assays, respectively. Expression of cell cycle-related proteins cyclin D1 and cyclin E and invasion-related protein matrix metalloproteinase 9 (MMP9) was determined by performing Western blotting and RT-PCR. Results Inhibition of Rabl 1 expression inhibited the proliferation and invasion of bladder cancer cells and downregulated the expression of cell cycle-related proteins cyclin D1 and cyclin E and invasion-related protein MMP9. Conclusion Our results suggest that Rabl 1 functions as a tumor protein and is involved in the progression of bladder cancer.

Effects of surgery combined with immunochemotherapy on the peripheral blood T lymphocyte subsets and C-reactive protein in patients with single-renal clear cell carcinoma / 中国基层医药

Objective To investigate the effects of surgery combined with immunochemotherapy on peripheral blood T lymphocyte subsets and C -reactive protein ( CRP) in patients with single renal cell carcinoma.Methods From June 2015 to June 2017,ninety patients with single-renal clear cell carcinoma who underwent radical resection of kidney in the Fourth Affiliated Hospital of China Medical University were selected ,and they were confirmed by preoperative ultrasound,CT and MRI diagnosis of unilateral renal space -occupying lesions.All patients were treated with kidney cancer immunochemotherapy.The peripheral blood T lymphocyte subsets and the changes of CRP levels of the patients before and after operation and after immunochemotherapy were observed.Results The CRP level of peripheral blood before operation was (9.12 ±4.98)μg/L,which after operationwas (28.29 ±10.23)μg/L,which after immunochemotherapy was (2.34 ±0.97)μg/L,the CRP level of peripheral blood after operation was higher than that before operation ,and the CRP level after immunochemotherapy was lower than that before surgery ,the difference was statistically significant ( F ＝6.78, P ＜0.05).The CD+3, CD+3CD+8,CD+4/CD+8levels before operation were (59.78 ±5.50)%,(34.56 ±6.23)%,(1.05 ±0.58)%,respectively,which after operation were (68.91 ± 7.49)%,(33.60 ±7.59)%,(0.98 ±0.76)%,respectively,which after immunochemotherapy were (62.31 ± 5.90)%,(21.90 ±4.55)%,(1.90 ±0.34)%,respectively.The CD+3level after operation was significantly higher than that before operation and after immunochemotherapy ,and the CD +3CD+8levels after immunochemotherapy were significantly lower than that before and after operation , and the CD +4/CD+8level after immunochemotherapy was significantly higher than that before and after operation ,the differences were statistically significant (F＝6.98,8.12, 7.23,all P＜0.05).Conclusion The immunochemotherapy can improve the expression level of peripheral blood T lymphocyte subgroup and CRP in patients with single -renal clear cell carcinoma who underwent radical resection of kidney,which can provide a reasonable basis for diagnosis and treatment of renal carcinoma .

Change trend of liver function indicators in different types of hyperlipidemia patients / 国际检验医学杂志

Objective To investigate the change trend of liver function indicators in different types of hyperlipidemia patients. Methods From July 2014 to July 2015 ,a total of 2571 patients with hyperlipidemia and 1063 normal people(control group) were collected in this research.All patients with hyperlipidemia were divided into the hypercholesterolemia group (high TC group ,n=258) ,hypertriglyceridemia group (high TG group ,n=859) and mixed type hyperlipidemia group(n=282) ,low high-density lipo-protein cholesterol group(low HDL-c group ,n=1172).The liver function indicators of total protein (TP) ,albumin (ALB) ,alanine aminotransferase(ALT ) ,aspartate aminotransferase (AST ) ,AST/ALT and globulin (GLB ) were measured in each group. Results The TP and ALB levels in the high TC group ,mixed group and low HDL group were significantly decreased compared with the control group ,the difference was statistically significant (P<0.05).The ALT ,AST ,AST/ALT and GLB levels in the four hyperlipidemia groups had different degrees of increase as compared with the control group ,the difference was statistically signifi-cant(P<0.05).The TP and ALB levels in the mixed group and the low HDL group were significantly lower than those in the high TG group and high TC group ,the difference was statistically significant (P<0.05).The ALT level in the low HDL group was sig-nificantly higher than that in the other three groups ,the difference was statistically significant (P<0.05).The AST/ALT level in the mixed group was significantly higher than the other three groups (P<0.05).The GLB level in the high TC group was signifi-cantly higher than the other 3 groups with statistical difference (P<0.05).Conclusion Blood lipid increase may induce the liver function injury.The detection of liver function indicators in the patients with hyperlipidemia will contribute to the early detection and treatment of fatty liver.

Characterization of bacteriophage vB_AbaP_PD-AB9 infecting Acinetobacter baumannii with broad host range / 中华检验医学杂志

Objective To isolate bacteriophages against extensively-drug resistant Acinetobacter baumannii from hospital sewage and analyze their biological characteristics.Methods Extensively-drug resistant Acinetobacter baumannii isolated from several hospitals in Shanghai during December, 2013 to July, 2014 were used as host bacteria, adopting double-layer agar method to isolate bacteriophages from raw sewage of these hospitals.The phage with broad host range was selected for further study, including observation of electron microscopic morphology, examination of thermal stability, pH stability and the optimal MOI, drawing of the adsorption, one-step-growth and infection curves, as well as sequencing of the phage genome DNA. Results An extensively-drug resistant Acinetobacter baumannii bacteriophage vB_AbaP_PD-AB9 ( PD-AB9 for short) with broad host range was isolated, and electron microscopy revealed it belonged to Podoviridae family.The optimal MOI of PD-AB9 was 0.001.PD-AB9 remained stable among 4 ℃to 50 ℃and pH 4 to 11.In the adsorption experiment, the adsorption rate of PD-AB9 reached above 95%within 5 min.PD-AB9 had a latent period of 4 min and a burst size of 213.PD-AB9 could obviously restrain the host growth, with faster effect at the higher MOIs (MOI=1, 0.1, 0.01) than at the lower ones (MOI=0.001, 0.000 1).Furthermore, genome of PD-AB9 proved to be a double-stranded linear DNA with size of 40 938 bp and GC content of 39.34%.Conclusions PD-AB9 exhibits good thermal stability, wide pH tolerance range, very fast adsorption, a short latent period, a large burst size and it could quickly cause effective host lysis after infection.Therefore, PD-AB9 is promised to act as a new antimicrobial agent to control drug-resistant Acinetobacter baumannii infections and its bio information remains to be further studied.

Correlations between the Expressions of SRSF1 and Survivn and the Pathological Features of Prostate Cancer / 中国医科大学学报

Objective To test the expression of serine/arginine rich splicing factor 1(SRSF1)and apoptosis inhibiting factor(Survivin) in prostate cancer,and study their correlation with the pathological features of prostate cancer,so as to put forward the new targets in the treatment of prostate cancer. Methods SRSF1 and Survivin protein was determined in 20 prostate tissue samples including prostate cancer(n=12)and benign prostat?ic hyperplasia(n=8)by immunohistochemical SP method. SRSF1 and Survivin was correlated to pathological features,and both the relevance was analyzed(no related reports at home and abroad). Results The positive expression rate of SRSF1 protein in prostate cancer tissue cells was 76.37± 5.06%,which was significantly higher than that of benign prostatic hyperplasia(11.30%±1.09%,P<0.05);the positive expression rate of Survivin protein in prostate cancer tissue cells was 86.93%±3.21%,which was significantly higher than that of benign prostatic hyperplasia(17.67%±1.99%, P<0.05);SRSF1 and Survivin protein expressed in prostate cancer organizations and were positively correlated to pathological Gleason grading, and there was significant correlation(P<0.05). Conclusion SRSF1 and Survivin protein were highly expressed in adenocarcinoma tissue,which were significantly increased than that of benign hyperplasia of prostate tissue. The positive expression SRSF1 and Survivin protein were positively cor?related to pathological Gleason grading.The expression of Survivin protein was elevated with the expression of SRSF1 protein in prostate cancer. These preliminary evidence indicated that SRSF1 may up?regulate the expression of Survivin,and thus promote the occurrence and development of prostate cancer.

Analysis on clinical distribution and antibacterial resistance of Acinetobacter Baumannii from 2010 to 2014 / 国际检验医学杂志

Objective To investigate the clinical distribution characteristics and trend in antibacterial resistance of Acinetobacter baumannii in Pudong Hospital Affiliated to Fudan University,so as to provide the guidance for clinical rational use of antibacterial agents and infection control.Methods SPSS 1 9.0 statistical software was adopted to retrospectively analyze the specimen source, department distribution and antibacterial resistance change of the 1 678 strains of Acinetobacter baumannii in this hospital from Jan-uary 2010 to October 2014.Results Clinical isolates of Acinetobacter baumannii mainly came from respiratory tract specimens(ac-counted for 79.1%).The intensive care unit(21.1%),department of neurosurgery(1 7.7%)and department of cardiology(1 7.6%) were the top three departments from which the strains were isolated.The isolates of Acinetobacter baumannii were highly resistant to the first and second generation of cephalosporins,cephamycin,ampicillin and nitrofurantoin,and the resistance rates reached a-bove 90%.The resistance rates of these isolates against carbapenems,aztreonam,cefperazone-sulbactam and ampicillin-salbactam showed obviously uptrends,but the resistance rates of these isolates against amikacin and cotrimoxazole showed downtrends.And the resistance rates of these isolates against other antibacterial agents stayed between 30% and 50%.During the five years,the de-tection rates of multi-drug resistant strains steadied around 35.0%.Though the detection rates of pan-drug resistant strains de-clined year by year,the strains were isolated each year.Conclusion The antibacterial resistance of Acinetobacter baumannii is seri-ous in this hospital,with multi-drug and pan-drug resistance persisting.It is necessary to enhance monitoring antibacterial resist-ance,ensure rational use of antibacterial agents,and promote implementation of disinfection and isolation,so as to prevent the spread and popularity of Acinetobacter baumannii resistance in hospital.

Effect of Drag-reducing Polymers on Coronary Microcirculation in Experimental Canine Model / 中国循环杂志

Objective: To test the feasibility of drag-reducing polymers (DRP) for improving coronary microcirculation in a canine model in order to provide the experimental basis for treating myocardial microcirculation dysfunction. Methods: A total of 8 dogs received open-chest surgery and they had intravenous injections, in turn, with adenosine (ADN), DRP 250 mg/L and DRP+ADN. The function y=A × (1-e-βt) was used to calculate the myocardium capillary volume (A value), capillary velocity (β value) and myocardial blood lfow (A ? β value) by myocardial contrast echocardiography. Results: With DRP infusion, the A value in experimental canine was similar to the baseline condition,P>0.05; while theβ value and A ? β value were signiifcantly increased as (0.57 ± 0.10) 1/s vs (0.23 ± 0.03) 1/s,P0.05. Conclusion: DRP improved coronary microcirculation primarily by modulating the β value in experimental canine model, and hopefully, this unique hemodynamics could provide a new approach for treating myocardial microcirculation dysfunction.

The mechanism of ultrasound-target microbubble destruction for accelerating neovascularisation in ischemic skeletal muscle / 实用医学杂志

Objective To investigate the role and possible mechanism of ultrasound-targeted microbubble destruction for accelerating neovascularisation in ischemic skeletal muscle. Methods Unilateral hind limb ischaemia was surgically induced in thirty wister rats. On postoperative day 7 , the rats were randomly divided into three groups: ultrasound-targeted microbubble destruction group (group A), ultrasound group (group B), and control group. After the end of the experiment , parafin sections for the skeletal muscle from one rat in each group were made to observe the changes in microstructure. The remaining rats were sacrificed at 24 h and on day 7. VEGF expression, inflammatory factor E-selectin, and monocyte chemotactic factor-1 (MCP-1) were detected in the rats. Results As compared with the other two goups, expressions of VEGF, neovascularization, E-selectin, and MCP-1 in the skeletal muscle were significantly increased in group A. Conclusions Microvascular rupture caused by ultrasound-targeted microbubble destruction can promote angiogenesis by stimulating secretion of endogenous VEGF in skeletal muscle; meanwhile, an increase in expression level of inflammatory factors may be one of the mechanisms.

Flexible ureteroscopy and holmium laser lithotripsy for treatment of upper urinary tract calculi in patients with autosomal dominant polycystic kidney disease.

The objective of the study was to investigate the safety and efficacy of flexible ureteroscopy and holmium laser lithotripsy for the management of patients with autosomal dominant polycystic kidney disease (ADPKD) and associated nephrolithiasis. Between 2005 and 2010, flexible ureteroscopic stone treatment was attempted in 13 patients with ADPKD. Two patients had bilateral renal stones. Most of the stones were located in the renal pelvis and/or calices with a stone size 1.7 cm in the largest diameter. The success rate and morbidity and complications were recorded. A total of 45 intrarenal calculi with a mean stone size of 5.6 mm (range 3-17) were identified. The mean number of stones per patients was 3.2 (range 2-5). The mean number of primary procedures was 1.2 (range 1-2). The overall stone-free rates after one and two procedures were 84.5 and 92.3%, respectively. Complications occurred in three procedures and consisted of low-grade fever in one procedure, flank pain in another procedure and stent pain in another procedure. No patient died. Flexible ureteroscopy with holmium laser lithotripsy is a safe and effective method for the treatment of patients with ADPKD and associated nephrolithiasis.

Ultrasound assessment of bladder detrusor wall thickness for non-invasive diagnosis of female bladder outlet obstruction / 中华泌尿外科杂志

Objective To evaluate the diagnostic accuracy of ultrasound bladder detrusor wall thickness (DWT) measurement for female bladder outlet obstruction (FBOO) and investigate the application of this non-invasive method for diagnosis of FBOO.Methods DWT was measured by linear ultrasound (7.5 MHz) either at a filling volume of 50％ of cystometric capacity or at 250 ml filling in 93 women undergoing pressure flow study (PFS) for lower urinary tract symptoms (LUTS).FBOO was defined as maximal flow rate (Qmax) of less than 12 ml/s combined with a detrusor pressure at maximal flow rate (Pdet Qmax)greater than 25 cm H2O.All the patients were divided into 2 groups according to FBOO and non-FBOO.The age,urodynamic parameters and DWT of the 2 groups were compared.Meanwhile DWT was evaluated for diagnosing BOO through receiver operating characteristic (ROC) curve.ResultsThe age (61.2 ± 8.3 vs 59.9 ± 7.7 years,P =0.44) and maximal cystometric capacity (292.2 ± 82.3 vs 308.1 ± 87.5 ml,P =0.37 ) between the 2 groups had no significant difference.DWT was significantly higher ( P =0.00 ) in FBOO group (42 cases,DWT 1.8 ±0.3 mm) compared to non-FBOO group (51 cases,1.4 ±0.2 mm).Furthermore maximal detrusor pressure (43.1 ± 11.2 vs 16.2 ± 7.1 cm H2O,P =0.00),Pdet Qmax (34.3 ±8.2 vs 13.1 ±7.8 cm n2O,P =0.00),Qmax(7.4 ±3.2 vs 17.4 ±4.1 ml/s,P =0.00),voided volume (157.1 ±63.7 vs 251.2 ±77.4 ml,P=0.00) and post-void residual volume (117.5 ±71.3 vs 37.7 ± 18.1 ml,P =0.00) had significant differences between the 2 groups.For a diagnosis of FBOO,DWT of 1.9 mm or greater had a positive predictive value of 100％,a negative predictive value of 62％,specificity of 100％ and sensitivity of 38％.ROC analysis revealed that DWT had a high predictive value for FBOO with an area under the curve of 0.88 ± 0.06.Conclusions Ultrasound DWT measurement for FBOO is non-invasive,convenient and reliable.DWT 1.9 mm or greater assessed by ultrasound has a high predictive value and specificity for FBOO and can replace PFS in some extent.However,this cutoff value needs to be validated in multiple center and larger population study.

A probable novel splicing isoform of human vascular endothelial growth factor / 南方医科大学学报

<p><b>OBJECTIVE</b>To characterize a new alternative splicing isoform of human vascular endothelial growth factor (VEGF) gene.</p><p><b>METHODS</b>The total RNA was extracted from the lung tissue of a legally aborted 4-month-old fetus and amplified by RT-PCR. The amplified product was cloned into the plasmid pMD18-T and plasmid pcDNA3.1- for sequence analysis.</p><p><b>RESULTS</b>Electrophoresis of the RT-PCR products displayed one short band for VEGF(121) (487 bp) and a long band. The latter was characterized to contain two fragments: one was normal VEGF(165) (619 bp), and the other (639 bp) had an identical nucleotide sequence to VEGF(165) with a 20 bp fragment inserted between exons 3 and 4. Sequence analysis showed that this 20-bp nucleotide was inserted from the 3' end of the third intron containing a splicing signal, thus causing shift mutation in the reading frame of VEGF gene and early appearance of the stop codon UAG in the middle of exon 4.</p><p><b>CONCLUSION</b>A new alternative splicing isoform of VEGF probably exists in the lung tissue of a legally aborted human fetus, and its biological significance remains to be further investigated.</p>

TRPC6 mediates the proliferation of human umbilical vein endothelial cells induced by DU145 conditioned medium / 中国医师杂志

Objective To investigate the influence of transient receptor potential canonical 6 (TRPC6) on the proliferation of hUVEC induced by the supematant from human prostate cancer cells (DU145). Methods Experiment group was treated with the mixture of DU145 cells supernatant and DMEM medium in different ratio, control group was treated with DMEM medium. The change of cell proliferation was detected by MTT method, and TRPC6 gene and protein was detected by PCR and Western-blot methods respectively. Results After incubated for 48h with the supematant from cultured DU145 cells,the population of hUVECs increased obviously, and the expression of TRPC6 genes and protein had clearly up-regulation. Conclusion The supernatant from cultured DU145 cells could effectively enhance the proliferation of hUVECs. The mechanisms might be that the proliferation of human umbilical vein endothelial cells was mediated by TRPC6.

Ultrasound measurement of detrusor wall thickness in equivocal bladder outlet obstruction / 中华泌尿外科杂志

Objective To estimate the application of ultrasound measurement of detrusor wall thickness (DWT) in the assessment of curative effect after operation. Methods Detrusor thickness was measured by linear ultrasound (7. 5 MHz) either at a filling volume of 50% of cystometric capacity or at 250 ml filling in 86 patients, who were diagnosed equivocal BOO, during a pressure-flow study. All patients accepted transurethral resection of the prostate. At 3 months post-surgery, the patients were divided into two groups according to curative effect after operation. The volume of the prostate, age and DWT were compared between the two groups. Results There was no difference in either age or volume of the prostate between the two groups. DWT was significantly higher (P＜0.01) in the more curative effect group (37 cases, DWT 2. 5±0.3 mm) compared to the less curative effect group (49 cases, 2.2±0. 3 mm). As a predictor of curative effect, DWT of 2. 8 mm or greater had a positive predictive value of 100%, a negative predictive value of 62%, specificity of 100% and sensitivity of 19%. Receiver operating characteristic analysis (ROC) revealed that DWT had a high predictive value for curative effect post-surgery with an AUC of 0. 84±0. 04. Conclusions In patients with equivocal BOO, ultrasonographically assessed detrusor thickness may have a predictive value for curative effect post-surgery. However, this cutoff value needs to be validated in a larger study population.

Combined percutaneous nephrostomy and ureteroscopic lithotripsy in the treatment of calculous obstructive pyonephrosis / 中华泌尿外科杂志

Objective To summarize the clinical experience of combined percutaneous nephrostomy(PCN)and ureteroseopic lithotripsy(URL)in the treatment of calculous obstructive pyonephrosis. Methods A total of 86 cases were underwent combined PCN and URL. Results Sixty-nine cases with lower ureteric calculi were treated successfully.During lithotripsy,calculous fragments migrated into renal pelvis in 6 of 17 cases with middle and upper ureteric calculi.These patients were placed with DJ stents and received antibiotics.The fragments passed OUt from 7 t0 16 days postoperatively.The rest 11 cases were placed with DJ stents and received antibiotics as well. They were accepted ESWL aher 2 or 3 weeks.The average operation time was 51 mins.No complication such as infection exacerbation,bacteremia,sepsis and shock occurred. Conclusions Combined PCN and URL is an effective and safe minimally invasive method tot treatment of calculous obstructive pyonephrosis.

Preparation and evaluation of nanometer-scale bubbles with surfaces of N-palmitoyl chitosan / 中华超声影像学杂志

Objective To develop nanometer-scale bubbles with surfaces of N-palmitoyl chitosan(PLCS) as ultrasound contrast agent and evaluate its characteristics and acoustic effects in vivo. Methods The PLCS nanobubbles were prepared using a cutting technique at differential high-frequency of shear speed. Both optical and transmission electron micrography were performed to determine the nanobubble size and morphology. Concentration, size-distribution and zeta potential of the PLCS nanobubbles were measured by cell counting chamber, Malvern lazer particle analyzer and zeta-sizer at 1-day, 45-day and 90-day. The acoustic effects of the PLCS nanobubbles on myocardium and renal tissue in 6 normal rats were observed using bolus infusion of the nanobubbles intravenously. The maximum video intensity(VI) was measured.Results The PLCS nanobubbles with nice round-shape and uniform site-distribution were demonstrated.The mean diameter,concentration and zeta potential of the PLCS nanobubbles were (617 ± 12) nm, (7.2 ±0.6) × 109/ml and (52.9 ± 1.3)mV at the 1-day,and all of parameters did not change significantly in 45-day and 90-day ( P ＞ 0. 05). A significant contrast-enhancement was noted on myocardium and renal tissue during infusion of the nanobubbles. VI on both tissues was (15.6 ± 1.1)GU and (27.3 ± 2.5)GU,respectively. The visual contrast-enhancement last up to (10 ± 2)min. Conclusions The PLCS nanometerscale bubbles have excellent physical-features and contrast-enhanced ultrasound effects in vivo. It may develop as a novel contrast ultrasound agent which could cross endothelial cell membrances.

Binding capability of microbubbles targeted to VCAM-1 under pulsatile high-shear flow conditions / 中华超声影像学杂志

Objective To assess the binding capability of microbubbles targeted to VCAM-1 using the parallel plate flow chamber mimic the pulsatile high-shear flow conditions of artery. Methods Targeted microbubbles were designed by conjugating monoclonal antibodies against mouse VCAM-1 to the lipid shell of the microbubbles via an "avidin-biotin" bridge. The binding and retention of targeted microbubbles to VCAM-1 (MBv) immobilized on a culture dish were assessed in a flow chamber at variable shear stress (0.5～ 16.0 dynes/cm2 ). The pulsatile flow conditions were generated and compared to the continuous flow conditions. The retentive ability of MBv was evaluated by the detachment test. Results The marked binding of MBv were seen in pulsatile and continuous flow conditions at low-shear flow conditions of 0.5 ～ 2dyn/cm2 ,but the binding rate in the pulsatile flow group was higher ( P ＜0. 05) than that in the continuous flow conditions. Furthermore,the marked binding of MBv was still noted at the highest shear rates (4～8dyn/cm2) under pulsatile flow conditions, while it was not observed under continuous flow conditions. The half detachment rate of MBv was high up to (20.7 ± 3. 1)dyn/cm2. Conclusions The targeted microbubbles binding to VCAM-1 specific and effective at high-shear stress under pulsatile flow conditions. The molecular ultrasound imaging can be potentially used in the high-shear conditions artery system.

Evaluation of left ventricular diastolic and systolic function of dogs on different status of acute myocardial ischemia with velocity vector imaging / 中国医学影像技术

Objective To evaluate left ventricular diastolic and systolic function of the dogs during different status of acute myocardial ischemia with velocity vector imaging (VVI). Methods Six healthy mongrel dogs were enrolled. Home-made artery constrictor was placed in the proximal coronary artery after opening the chest of dogs to produced different grades of coronary artery stenosis. Mean of peak diastolic velocity (Em), peak strain rate of diastole (Esr), mean of peak systolic velocity (Sm), peak strain rate of systole (Ssr), ejection fraction (EF) and left ventricular pressure were measured. Results There was good linear correlation between Em and Esr by VVI and left ventricular end diastolic pressure (LVEDP) (r=-0.834, P＜0.001 and r=-0.703, P＜0.001, respectively). Em and LVEDP had better correlation than that between Esr and LVEDP (P=0.032). Sm, Ssr or EF had significant correlation with +dp/dt_(max) (r=0.883, P＜0.001, r=0.772, P＜0.001 and r=0.647, P＜0.001, respectively). Significant difference was observed for correlation coefficient between Em and Esr and EF (P＜0.001). Conclusion Em and Sm are sensitive echocardiography indexes to evaluate left ventricular diastolic and systolic function, and are better than EF, Esr and Ssr.

Evaluation of non-critical coronary stenosis by coherent contrast imaging / 中华超声影像学杂志

Objective To investigate whether non-critical coronary stenosis can be detected by coherent contrast imaging(CCI) at rest without stress.Methods Three degrees of stenosis were made in left anterior descending of 12 dogs.Myocardial contrast echocardiography(MCE) was performed with CCI and the correlation among the variables of MCE curve and the degrees of stenosis were analyzed by cubic regression.Results The time to peak was significantly prolonged with progressive coronary stenosis (P＜0.01) and related to the degree of stenosis (R~2=0.991,P＜0.001).Conclusions CCI could be used to detected non-critical coronary stenosis at rest without stress.