Objective: To establish a labeling method for bacterial outer membrane vesicle (OMV) based on luciferase reporting gene. Methods: By utilizing the characteristics that high abundance of outer membrane protein A (OmpA) presented on the surface of bacterial OMV, the outer membrane protein-luciferase fusion protein was constructed to position the luciferase on the surface of the outer membrane vesicle, and the number of bacterial OMV was evaluated based on the luciferase activity. Results: The OmpA-NanoLuc fusion protein expression vector was constructed successfully, and the outer membrane vesicles secreted by the subject strains after the expression of the fusion protein displayed stable luciferase activity. The number of bacterial outer membrane vesicles was semi-quantitative detrmined by measuring the activity of fluorescein enzyme. Conclusion A semi-quantitative method based on luciferase labeling was developed for the detection of extracellular vesicles, which could be used to evaluate the secretion level of specific strains.

Objective:To compare the efficacy and safety of ultrasound-guided percutaneous translumial septal myocardial ablation in dogs using laser and radiofrequency.Methods:Twelve healthy adult Beagle dogs (males or females) were randomly divided into two groups, namely, group laser and group radiofrequency (6 dogs each group). Under ultrasound guidance, laser fiber or radiofrequency ablation needle was respectively inserted into the basal and middle segments of the interventricular septa via the percutaneous transapical approach to perform ablation. The Beagle dogs received radiologic examination, laboratory tests and pathological detection before ablation, immediately after ablation, at 1 week after ablation, and at 1 month after ablation, respectively. The efficacy and safety of the two ablation procedures were compared.Results:All dogs survived after ablation. The peak gradient of LVOT decreased immediately after ablation using either laser or radiofrequency ( P<0.05), but it increased at 1 week after ablation than before ( P<0.05). At 1 month after ablation, no significant differences were found in the peak gradient of LVOT compared with that before surgery ( P<0.05). The interventricular septum thickness was increased immediately after ablation using either laser or radiofrequency than before ( P<0.05), but it decreased at 1 week and at 1 month after surgery than before ( P<0.05). The ablation zone using radiofrequency was slightly larger than that of using laser[(372.50±69.06)mm 3 vs (116.65±20.15)mm 3, P<0.001], and the surgical time of the former was significantly shorter than that of using laser [(56.00±3.22)s vs (260.00±65.39)s, P<0.05)]. Conclusions:Ultrasound-guided percutaneous translumial septal myocardial ablation is feasible, safe and effective using either laser or radiofrequency. Comparatively speaking, radiofrequency ablation is more simple and convenient.

Objective:To compare the values of medical image technologies in evaluating the tansperineal laser ablation (TPLA) in canine prostate.Methods:TPLA (3 W/600 J and 3 W/1 200 J) were operated in the prostate of six adult male beagles guided by transrectal ultrasound (TRUS). TRUS, transrectal contrast-enhanced ultrasound (TR-CEUS) and multiparameter magnetic resonance imaging (mpMRI) were used to evaluate the ablation on the day of TPLA, one week and one month after TPLA. The animals were sacrificed for pathology to calculate the volume of the ablation. SPSS 22.0 software was used for statistical analysis.Results:TRUS could be used to guide and observe the puncture and ablation process during TPLA. TR-CEUS and contrast enhanced MRI showed good consistency in the volume of ablation ( P>0.05). One month after TPLA, the ablation volume were (1.69±0.51)ml vs (1.73±0.36)ml vs (1.52±0.41)ml (3 W/600 J) and (2.23±0.54)ml vs (2.34±0.29)ml vs (2.19±0.34)ml (3 W/1 200 J) measured by the two medical image technologies and pathology, with good consistency ( P>0.05). Conclusions:TRUS can be used to guide and observe the puncture and ablation process during TPLA. TR-CEUS and mpMRI can be used for postoperative evaluation and follow-up of TPLA. The former has advantages of real-time and low price, which can be promoted and applied in clinical practice.

Objective:To prepare ultrasound-responsive nanodroplets with block polymer PEG-PCL as shell and perfluoropentane (PFP) as core, and study the effects of mechanical index (MI) on contrast-enhanced imaging properties of nanodroplet.Methods:PEG-PCL micelles were first prepared by dialysis, and then the micelles were mixed with PFP for emulsification to obtain nanodroplets. The particle size and zeta potential of nanodroplets were measured, and the morphology of nanodroplets were observed using transmission electron microscope (TEM). The stability of nanodroplets after storage at 25 ℃ and 37 ℃ was investigated. The phase transition and contrast-enhanced imaging of nanodroplets in vitro under a series of mechanical index (MI) were studied using an ultrasound diagnostic instrument.Results:The particle size of the nanodroplets was (356.6±5.6)nm, and the zeta potential was -(7.30±0.14)mV. The nanodroplets were close to spherical under TEM and had a clear core-shell structure. The particle size and dispersion of the nanodroplets increased after storage at 37 ℃ and 25 ℃. For imaging in vitro, no acoustic signal were observed at 25 ℃ when the MI varied from 0.08 to 1.0. At 37 ℃, acoustic signals were observed when MI≥0.4, and the intensity was stronger for higher MIs.Conclusions:The contrast-enhanced imaging of nanodroplets are closely related to the MI, and a higher MI could induce the phase transition of more nanodroplets and produce stronger contrast enhancement. This study could provide basis for the application of polymeric nanodroplets in ultrasound diagnosis and targeted therapy.

ZNF804A rs1344706 has been identified as one of the risk genes for schizophrenia. However, the neural mechanisms underlying this association are unknown. Given that ZNF804A upregulates the expression of COMT, we hypothesized that ZNF804A may influence brain activity by interacting with COMT. Here, we genotyped ZNF804A rs1344706 and COMT rs4680 in 218 healthy Chinese participants. Amplitudes of low-frequency fluctuations (ALFFs) were applied to analyze the main and interaction effects of ZNF804A rs1344706 and COMT rs4680. The ALFFs of the bilateral dorsolateral prefrontal cortex showed a significant ZNF804A rs1344706 × COMT rs4680 interaction, manifesting as a U-shaped modulation, presumably by dopamine signaling. Significant main effects were also found. These findings suggest that ZNF804A affects the resting-state functional activation by interacting with COMT, and may improve our understanding of the neurobiological effects of ZNF804A and its association with schizophrenia.