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Objective:To prepare urokinase targeted thrombus microbubbles combined with low frequency ultrasound to dissolve thrombus in rabbit femoral artery, and to explore the mechanism of thrombolysis through the change of urokinase concentration.Methods:Twenty-four rabbits with thrombosed femoral artery were randomly divided into four treatment groups: urokinase alone (UK) group, ultrasound with non-targeted microbubble and urokinase (US+ M+ UK) group, platelet-targeted microbubble with urokinase (R+ UK) group, ultrasound with platelet-targeted microbubble and urokinase (US+ R+ UK) group. Thrombus-targeted microbubbles were injected through the ear vein and irradiated by ultrasound for 30 minutes, and the pulsed Doppler blood flow meter was used to continuously monitor the blood flow at 0 min, 10 min, 20 min, 30 min, 60 min, 90 min and 120 min after injection. At the same time, the changes in urokinase concentration were monitored, and the characteristics of blood flow and urokinase concentration changes were analyzed.Results:UK and US+ M+ UK groups failed to show recanalization at 120 minutes after treatment.In contrast, the US+ R+ UK and R+ UK groups both achieved persistent recanalization( P<0.001). Compared with the basal state. Both the R+ UK group and R+ UK+ US group showed a decrease at 60 minutes, and the difference was statistically significant( P<0.05). Conclusions:In the thrombolysis process of low-frequency ultrasound combined with a targeted contrast agent carrying urokinase, the targeting can make the local urokinase concentration of thrombus reach the highest level. At the same time, ultrasound and targeted microbubbles promote urokinase to enter the thrombus, and finally achieve the strongest thrombolytic effect.
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Corona virus disease 2019 (COVID-2019) is an acute respiratory tract infectious disease caused by infection with 2019 novel coronavirus(2019-nCoV), which is mainly characterized with pulmonary inflammatory lesions, strong infectivity and long incubation period. At present, the gold standard for diagnosis of COVID-2019 is positive nucleic acid test result. However, nucleic acid test Results: of some patients are false negative, and the number of patients need to be screened is so large. For asymptomatic patients and the large number of patients needed to be screened, imaging examinations are particularly important. The main points of CT and ultrasonic examination in auxiliary diagnosis of COVID-2019, the advantages of ultrasonic examination and protective specifications were reviewed in this article.
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Objective To construct the uItrasound microbubbIes co-carrying recombinant adenovirus containing stromal cell derived factor 1 (SDF-1α) and bone morphogenetic protein 2 (BMP2),and to study the maximum efficiency of carrying adenovirus and the optimum proportion of double gene combined with ultrasound contrast agents.Methods Microbubbles were combined separately with recombinant adenovirus co-expression of enhanced green fluorescent protein and SDF-1α(pAd-EGFP/SDF-1α) as well as red fluorescence protein and BMP2 (pAd-RFP/BMP2) via biotin-streptavidin method,and the maximum efficiency of carrying DNA in microbubbles was detected.Three microbubbles with binary vectors were prepared by blending the two above-mentioned pAd at different ratio (1 ∶1,1 ∶ 2,2 ∶ 1) into the microbubbles.The microbubbles with binary vectors were evaluated though physiochemical properties,fluorescence microscope and flow cytometry to test the carrying rate of DNA in microbubbles.Results There was no significant difference in PH,average diameter and concentrations between targeted microbubbles and control group (P ＞0.05).The carrying efficiency of DNA increased with virus loads in microbubbles,but lowered if further increasing virus amount after reaching saturation.When the proportion of binary vectors and microbubbles was 1 ∶ 1,its efficiency of carrying SDF-1α gene and BMP-2 was approximately equal,and flow cytometry demonstrated that the positive rate of microbubbles labeled by both fluorescein isothiocyanate(FITC) and rhodamine was (65.6 ± 0.5)％.However,it was (59.0 ± 2.3)％ when their proportion was the 2 ∶ 1,which was significantly lower than those when other two proportions (1 ∶ 1 and 1 ∶ 2).Under the fluorescence microscope,the targeted microbubbles were equally surrounded by bright green or red fluorescence.Conclusions Ultrasound microbubbles of double genes carrying EGFP/SDF-1a and RFP/BMP2 is made successfully via biotin-streptavidin method.The optimal proportion of combining microbubbles with double gene is 1 ∶1,which can reveal the optimum load rate and stable combination.
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Objective:To observe the therapeutic effect of donepezil combined nimodipine on vascular dementia. Methods:A total of 45 patients with vascular dementia aging 54~76 years were randomly divided into donepezil +nimodipine group (n= 24)and huperzine + piracetam group (n= 21).Scores of mini-mental state examination (MMSE)and activity of daily living (ADL)were examined in two groups before and after treatment,and therapeu-tic effect was compared between two groups.Results:Compared with before treatment,after treatment,MMSE score [(15.8±6.3)scores vs.(21.6±7.4)scores]significantly rose and ADL score [(50.3±6.4)scores vs.(40.2 ±7.1)scores]significantly reduced in donepezil + nimodipine group;MMSE score [(14.6±6.9)scores vs.(18.5 ±7.2)scores]significantly rose,ADL score [(49.3±7.8)scores vs.(43.5±8.2)scores]significantly reduced in huperzine + piracetam group,P <0.01 all;but there were no significant difference between two group after treat-ment (P =0.08,0.07).Conclusion:Therapeutic effect of donepezil combined nimodipine on vascular dementia is quite to huperzine + piracetam.