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1.
International Journal of Surgery ; (12): 212-216, 2024.
مقالة ي صينى | WPRIM | ID: wpr-1018117

الملخص

In recent years, recombinant human urokinase (rhPro-UK) has been widely used in the treatment of a variety of thromboembolic diseases, with significant efficacy and no obvious adverse reactions. In addition, it has a wide range of applications in many new technology fields. This article focuses on the application of rhPro-UK in the treatment of acute myocardial infarction, cerebrovascular disease, lower extremity deep vein thrombosis, arterial thrombosis and other diseases. rhPro-UK has demonstrated good thrombolytic efficacy and safety in these diseases, especially in patients with acute myocardial infarction, and adjuvant PCI therapy can significantly increase myocardial reperfusion, improve cardiac function, and do not increase the risk of bleeding. For cerebrovascular disease, rhPro-UK can significantly improve the degree of neurological deficit and has a high safety profile. In the treatment of lower extremity deep vein thrombosis, rhPro-UK has shown superior thrombolytic efficacy and safety compared with urokinase. For arterial thrombosis and biological stents, the use of rhPro-UK has also achieved some efficacy, but more research is needed to confirm its efficacy and safety. In addition, ultrasound-mediated drug-loaded thrombolysis systems also have potential applications in rhPro-UK therapy. Future research on rhPro-UK will focus more on the development of new technologies.

2.
مقالة ي صينى | WPRIM | ID: wpr-1027169

الملخص

Objective:To investigate the myocardial protective effect of extracorporeal cardiac shock wave therapy (CSWT) combined with sulfur hexafluoride microbubble post-conditioning on myocardial ischemia-reperfusion injury (MI/RI) in rats, and to provide theoretical support for clinical treatment of MI/RI.Methods:A total of 32 male SD rats were randomly divided into 4 groups: sham operation group (Sham group), MI/RI group (IR group), CSWT group (IR+ SW group), and CSWT combined with sulfur hexafluoride microbubble treatment group (IR+ SW+ MB group), with 8 rats in each group. Therapeutic intervention was performed in IR+ SW group and IR+ SW+ MB group on the 1st, 3rd and 5th day after modeling. The left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) of the rats were measured by echocardiography before and after treatment. On the 7th day, myocardial fibrosis was assessed by Masson staining, and cardiomyocyte apoptosis was observed by TUNEL staining. The myocardial apoptotic proteins Bcl-2, BAX, Cleaved-Caspase-3 and Cleaved-Caspase-9 in the infarct boundary area were detected by Western blot. The differences of the above indexes among different groups were compared.Results:①There was no significant change in heart rhythm and heart rate among the groups before and after treatment, and there was no significant difference in heart rate ( P>0.05). ②The echocardiographic results after treatment showed that, compared with IR group, LVEDD and LVESD in IR+ SW group and IR+ SW+ MB group decreased in turn, while LVEF and LVFS increased in turn with significant differences between each two groups (all P<0.05). ③Compared with IR group, the degrees of myocardial fibrosis and apoptosis in IR+ SW group and IR+ SW+ MB group were alleviated in turn, and the relief in IR+ SW+ MB group was the most obvious. Quantitative analysis showed that compared with IR group, the proportions of cardiomyocyte apoptosis in IR+ SW group and IR+ SW+ MB group decreased in turn, and there were significant differences between each two groups (all P<0.05). ④The results of Western blot detection showed that compared with IR group, the levels of Bcl-2 in IR+ SW group and IR+ SW+ MB group increased in turn, while the levels of BAX and the activation level of Caspase-3 and Caspase-9 protein decreased in turn. These differences were all statistically significant between each two groups (all P<0.05) except for the activation level of Caspase-3 protein between IR+ SW group and IR+ SW+ MB group ( P>0.05). Conclusions:CSWT combined with sulfur hexafluoride microbubble therapy can improve left ventricular remodeling and left ventricular systolic function by inhibiting cardiomyocyte apoptosis.

3.
مقالة ي صينى | WPRIM | ID: wpr-992842

الملخص

Objective:To investigate the effect of microbubbles combined with gentamicin on the clearance of bacterial biofilms and the healing of diabetic foot ulcers under low-frequency ultrasound.Methods:From July 2021 to June 2022, 27 patients with chronic diabetic foot ulcers complicated with infection were prospectively selected from the Trauma Center of the Second Affiliated Hospital of Chongqing Medical University. The patients were divided into low-frequency ultrasound + microbubbles + gentamicin ointment group, low-frequency ultrasound + microbubbles group, and gentamicin ointment group by using a random number table, with 9 patients in each group. The three groups were all treated with simple debridement by the same surgeon.Afterward, in the low-frequency ultrasound+ microbubbles+ gentamicin ointment group, the wounds covered by 4% microbubble suspension were firstly irradiated with low-intensity focused ultrasound for 5 min, and then evenly applied with gentamicin ointment. In the low-frequency ultrasound + microbubbles group, the wounds covered by 4% microbubble suspension were irradiated with low-intensity focused ultrasound for 5 min. The gentamicin ointment group was treated with gentamicin ointment evenly. The treatment lasted for 2 weeks, and secretions and tissue specimens were collected during and 2 weeks after the treatment, respectively. The general indexes of wound surface (including ulcer depth score, secretion exudation score, fresh granulation tissue growth score, and total index score), ulcer area, ulcer healing rate, as well as negative rate of secretion culture were compared among the three groups after treatment. Additionally, the structural changes in bacterial biofilms under a scanning electron microscope and colony count under a laser confocal scanning microscope were compared among the three groups after treatment.Results:No significant differences were found in the general datas among the three groups (all P>0.05). After treatment for 2 weeks, the overall general indexes showed statistically and significant differences among the three groups (all P<0.05). Each index score in the low-frequency ultrasound + microbubbles + gentamicin ointment group was lower than that in the low-frequency ultrasound + microbubbles group and the gentamicin ointment group (all P<0.05). There were no significant differences in overall ulcer area among the three groups ( P>0.05). The overall ulcer healing rate presented significant differences among the three groups ( P<0.05). The healing rate in the low-frequency ultrasound + microbubbles + gentamicin ointment group was higher than that in the low-frequency ultrasound + microbubbles group and the gentamicin ointment group (all P<0.05). The overall negative rates of secretion culture among the three groups were significantly different ( P<0.05), the negative rate in the low-frequency ultrasound + microbubbles + gentamicin ointment group was higher than that in the low-frequency ultrasound + microbubbles group and the gentamicin ointment group (all P<0.05). Scanning electron microscopy confirmed bacterial biofilm infection in the three groups before treatment. After treatment for 2 weeks, the biofilm formation in the low-frequency ultrasound + microbubbles + gentamicin ointment group reduced significantly, while the low-frequency ultrasound + microbubbles group and the gentamicin ointment group had little change compared with that before treatment. Significant differences were detected in total colony count among the three groups under the confocal microscope ( P<0.05). The colony count in the low-frequency ultrasound + microbubbles + gentamicin ointment group was lower than that in the low-frequency ultrasound + microbubbles group and the gentamicin ointment group (both P<0.05). Conclusions:Ultrasound microbubbles combined with gentamicin can clear bacterial biofilms and promote the healing of diabetic foot ulcers.

4.
مقالة ي صينى | WPRIM | ID: wpr-992875

الملخص

Objective:To prepare the resiquimod-loaded lipid microbubbles R848-MBs, evaluate their enhanced ultrasound imaging and high intensity focused ultrasound (HIFU) ablation effects, and explore their ability to improve tumor immune microenvironment synergize with HIFU.Methods:R848-MBs were prepared by the thin film hydration-mechanical shock method; The basic characteristics and safety of R848-MBs were detected, the HIFU controlled-release characteristics were verified in vitro and the drug metabolism and biological distribution were investigated in vivo. The ability of enhancing ultrasound imaging was observed in vitro and in vivo. To investigate the enhanced HIFU ablation effect of R848-MBs, six EMT6 tumor-bearing mice were randomly divided into HIFU group and R848-MBs+ HIFU group, three mice in each group, the changes in contrast average sound intensity before and after ablation in mouse tumor areas and the change of ultrasound image gray value in tumor area were evaluated, the tumor were resected to observe the coagulative necresis by TTC staining and HE staining. Forty-five tumor-bearing mice were randomly divided into control group, Free R848 group, HIFU group, Blank-MBs+ HIFU group and R848-MBs+ HIFU group, nine mice in each group. On the third day after treatment, 3 mice in each group were randomly selected and killed, to evaluate the ability of R848-MBs to improve tumor immune microenvironment synergize with HIFU. The expression level of CRT on the surface of tumor cells were detected by immunofluorescence staining, the proportion of mature DC in lymph nodes, spleen, and CD8 + T cells in spleen were detected by flow cytometry. The treatment effectiveness of each group( n=6) were evaluated by measuring tumor volume, observing and drawing survival curves. Results:The R848-MBs lipid microbubbles with good safety were successfully prepared, with a concentration of 2.58×10 9/ml, as spherical bubbles under optical microscope and laser confocal microscopy, in a particle size of (1.72±0.11)μm, at a surface potential of (-10.16±0.73)mV. The cumulative drug release was up to 83.44% after HIFU (90 W, 3 s) in vitro. The concentration of R848 in plasma decreased rapidly, and the drug concentration in tumor tissue of the R848-MBs+ HIFU group was higher than that of the R848 group 24 hours after treatment ( P<0.01). The ultrasound imaging of R848-MBs was significantly enhanced in contrast mode in vitro and in vivo; R848-MBs can significantly enhance the HIFU ablation effect, the contrast average sound intensity change in the tumor area before and after ablation in the R848MBs+ HIFU group was greater than that in the R848 group ( P<0.05), and the immediate ultrasound grayscale value change in the HIFU+ R848-MBs group was 46.34±3.21, which was significantly greater than that in the HIFU group (10.67±1.53), with statistical significance ( P<0.000 1). Coagulation necrosis was observed in tumor HE staining and TTC staining. The results of treatment efficacy in vivo showed that R848-MBs+ HIFU group had the strongest therapeutic effect, and R848-MBs combined with HIFU treatment could significantly prolong the survival period of mice compared with intravenous injection of free R848 ( P<0.01). Immunofluorescence staining and flow cytometry results showed an increase in the expression level of CRT on the surface of tumor tissue in the R848-MBs combined with HIFU group, and the percentage of mature DC in tumor draining lymph nodes (58.53±1.04)% were significantly higher than those in the HIFU group (37.56±2.13)% ( P<0.001), and the percentage of mature DC in the spleen (70.65±1.91)% were significantly higher than those in the HIFU group (36.46±3.89)% ( P<0.001), the percentage of CD8 + T cells in the spleen (27.46±3.04)% was significantly higher than that in the HIFU group (18.69±0.29)% ( P<0.01). Conclusions:The HIFU controlled-release lipid microbubbles R848-MBs can not only enhance the efficiency of HIFU ablation, but also improve the tumor immune microenvironment.

5.
Acta Pharmaceutica Sinica B ; (6): 4983-4998, 2023.
مقالة ي الانجليزية | WPRIM | ID: wpr-1011219

الملخص

Lipid-coated microbubbles are widely used as an ultrasound contrast agent, as well as drug delivery carriers. However, the two main limitations in ultrasound diagnosis and drug delivery using microbubbles are the short half-life in the blood system, and the difficulty of surface modification of microbubbles for active targeting. The exosome, a type of extracellular vesicle, has a preferentially targeting ability for its original cell. In this study, exosome-fused microbubbles (Exo-MBs) were developed by embedding the exosome membrane proteins into microbubbles. As a result, the stability of Exo-MBs is improved over the conventional microbubbles. On the same principle that under the exposure of ultrasound, microbubbles are cavitated and self-assembled into nano-sized particles, and Exo-MBs are self-assembled into exosome membrane proteins-embedded nanoparticles (Exo-NPs). The Exo-NPs showed favorable targeting properties to their original cells. A photosensitizer, chlorin e6, was loaded into Exo-MBs to evaluate therapeutic efficacy as a drug carrier. Much higher therapeutic efficacy of photodynamic therapy was confirmed, followed by cancer immunotherapy from immunogenic cell death. We have therefore developed a novel ultrasound image-guided drug delivery platform that overcomes the shortcomings of the conventional ultrasound contrast agent and is capable of simultaneous photodynamic therapy and cancer immunotherapy.

6.
Journal of Biomedical Engineering ; (6): 1209-1216, 2023.
مقالة ي صينى | WPRIM | ID: wpr-1008952

الملخص

Correlation between nonlinear subharmonic scattering of ultrasound contrast agent microbubbles and ambient pressure is expected to be used for local brain tissue pressure monitoring. Although high-frequency ultrasound has achieved high-resolution imaging of intracranial microvessels, the research on high-frequency subharmonic scattering characteristics of microbubbles is insufficient at present, which restricts the research progress of estimating local brain tissue pressure based on high-frequency subharmonic scattering of microbubbles. Therefore, under the excitation of 10 MHz high-frequency ultrasound, the effects of different acoustic pressures and ambient pressures on the high-frequency subharmonic scattering characteristics of three different ultrasound contrast agents including SonoVue, Sonazoid and Huashengxian were investigated in this in vitro study. Results showed that the subharmonic scattering amplitudes of the three microbubbles increased with the increase of ambient pressure at the peak negative acoustic pressures of 696, 766 and 817 kPa, and there was a favorable linear correlation between subharmonic amplitude and ambient pressure. Under the above three acoustic pressures, the highest correlation coefficient of SonoVue was 0.948 ( P = 0.03), the highest sensitivity of pressure measurement was 0.248 dB/mm Hg and the minimum root mean square error (RMSE) was 2.64 mm Hg. Sonazoid's highest correlation coefficient was 0.982 ( P < 0.01), the highest sensitivity of pressure measurement was 0.052 dB/mm Hg and the minimum RMSE was 1.51 mm Hg. The highest correlation coefficient of Huashengxian was 0.969 ( P = 0.02), the highest sensitivity of pressure measurement was 0.098 dB/mm Hg and the minimum RMSE was 2.00 mm Hg. The above in vitro experimental results indicate that by selecting ultrasound contrast agent microbubbles and optimizing acoustic pressure, the correlation between high-frequency subharmonic scattering of microbubbles and ambient pressure can be improved, the sensitivity of pressure measurement can be upgraded, and the measurement error can be reduced to meet the clinical demand for local brain tissue pressure measurement, which provided an important experimental basis for subsequent research in vivo.


الموضوعات
Contrast Media , Microbubbles , Ultrasonography/methods
7.
Chinese Journal of Medical Imaging ; (12): 1337-1341, 2023.
مقالة ي صينى | WPRIM | ID: wpr-1026341

الملخص

Nowadays,the application of ultrasound is not only used in clinical imaging,but also extended in the study of drug delivery.Diagnostic ultrasound combined with microbubbles can effectively open the biological barriers,which can enhance the targeted delivery of drugs and be beneficial to the combination of ultrasound and disease treatment.This review summarizes the biological effects of ultrasound,the characteristics of ultrasound microbubbles and the potential ability that solving the biological barrier problems in cancer therapy by using ultrasound targeted microbubble destruction,hoping to provide some reference for the further development of therapeutic ultrasound as a safe and effective drug targeted delivery strategy.

8.
مقالة ي صينى | WPRIM | ID: wpr-1027144

الملخص

Objective:To investigate the synergistic effect of physical intervention and chemotherapeutic drug therapy on tumor growth by blocking tumor microvessels and injecting chemotherapy drug Endostar (ecombinant human vascular endostatin injection) to inhibit tumor neovascularization by low intensity ultrasound induced microbubble cavitation combined with hemocoagulase.Methods:Seventy-five male NU/NU mice bearing human-derived lung adenocarcinoma, weighing 25-30 g, were randomly divided into microbubble-enhanced ultrasonic cavitation+ Endostar group (MEUC+ Endostar), microbubble-enhanced ultrasonic cavitation+ hemocoagulase+ Endostar group (MEUC+ HC+ Endostar), microbubble-enhanced ultrasonic cavitation (MEUC), Endostar group (Endostar) and sham group. Fifteen mice in each group were given the corresponding treatment intervention for 4 consecutive days followed by 4 days of aseptic feeding. Two-dimensional ultrasound and contrast-enhanced ultrasound (CEUS) were performed before intervention, immediately after intervention and 4 days after intervention, respectively. Tumor tissues were obtained for vascular endothelial growth factor immunofluorescence staining, and microvessel density (MVD) was observed.Results:There was no difference in tumor volume between the groups before the intervention ( P>0.05). Immediately after the intervention, filling defects were observed in MEUC+ Endostar group, MEUC+ HC+ Endostar group and MEUC group, while filling was good in Endostar group and sham group; 4 days after the intervention, filling defects were observed in MEUC+ Endostar group and MEUC+ HC+ Endostar group. The filling defect was still present in Endostar group, while partial recovery of perfusion was performed in MEUC group, and PI and AUC were still significantly lower in MEUC+ HC+ Endostar group than in the other groups ( P<0.05). When tumor tissues were obtained 4 days after the intervention, the MVD in MEUC+ HC+ Endostar group was significantly lower than that in the remaining groups, and the difference of MVD in tumor tissue was statistically significant ( P<0.05). Conclusions:Low intensity ultrasound induced microbubble cavitation combined with hemocoagulase and Endostar can produce a synergistic effect in blocking tumor microvessels and inhibiting tumor angiogenesis, which can more effectively inhibit tumor growth.

9.
Arq. bras. cardiol ; 118(4): 756-765, Apr. 2022. tab, graf
مقالة ي البرتغالية | LILACS-Express | LILACS | ID: biblio-1374346

الملخص

Resumo Fundamento Demonstrou-se recentemente que a aplicação de ultrassom de alta energia com microbolhas, técnica conhecida como sonotrombólise, causa a dissolução de trombos intravasculares e aumenta a taxa de recanalização angiográfica no infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAM-CSST). Objetivo Avaliar o efeito da sonotrombólise nos índices de motilidade e perfusão miocárdicas em pacientes com IAM-CSST, utilizando a ecocardiografia com perfusão miocárdica em tempo real (EPMTR). Método Uma centena de pacientes com IAM-CSST foram randomizados em dois grupos: Terapia (50 pacientes tratados com sonotrombólise e angioplastia coronária primária) e Controle (50 pacientes tratados com angioplastia coronária primária). Os pacientes realizaram EPMTR para analisar a fração de ejeção do ventrículo esquerdo (FEVE), o índice de escore de motilidade segmentar (IEMS) e o número de segmentos com defeito de perfusão miocárdica, 72 horas após o IAM-CSST e com 6 meses de acompanhamento. Foi considerado significativo p < 0,05. Resultados Pacientes tratados com sonotrombólise apresentaram FEVE mais alta que o grupo Controle em 72 horas (50 ± 10% vs. 44 ± 10%; p = 0,006), e essa melhora foi mantida em seis meses (53 ± 10% vs. 48 ± 12%; p = 0,008). O IEMS foi similar nos grupos Terapia e Controle em 72 horas (1,62 ± 0,39 vs. 1,75 ± 0,40; p = 0,09), mas tornou-se menor no grupo Terapia em 6 meses (1,46 ± 0,36 vs. 1,64 ± 0,44; p = 0,02). O número de segmentos com defeito de perfusão não foi diferente entre os grupos em 72 horas (5,92 ± 3,47 vs. 6,94 ± 3,39; p = 0,15), mas ficou menor no grupo Terapia em 6 meses (4,64 ± 3,31 vs. 6,57 ± 4,29; p = 0,01). Conclusão A sonotrombólise em pacientes com IAM-CSST resulta na melhora dos índices de motilidade e perfusão ventricular ao longo do tempo.


Abstract Background It has recently been demonstrated that the application of high-energy ultrasound and microbubbles, in a technique known as sonothrombolysis, dissolves intravascular thrombi and increases the angiographic recanalization rate in patients with ST-segment-elevation myocardial infarction (STEMI). Objective To evaluate the effects of sonothrombolysis on left ventricular wall motion and myocardial perfusion in patients with STEMI, using real-time myocardial perfusion echocardiography (RTMPE). Methods One hundred patients with STEMI were randomized into the following 2 groups: therapy (50 patients treated with sonothrombolysis and primary coronary angioplasty) and control (50 patients treated with primary coronary angioplasty). The patients underwent RTMPE for analysis of left ventricular ejection fraction (LVEF), wall motion score index (WMSI), and number of segments with myocardial perfusion defects 72 hours after STEMI and at 6 months of follow-up. P < 0.05 was considered statistically significant. Results Patients treated with sonothrombolysis had higher LVEF than the control group at 72 hours (50% ± 10% versus 44% ± 10%; p = 0.006), and this difference was maintained at 6 months of follow-up (53% ± 10% versus 48% ± 12%; p = 0.008). The WMSI was similar in the therapy and control groups at 72 hours (1.62 ± 0.39 versus 1.75 ± 0.40; p = 0.09), but it was lower in the therapy group at 6 months (1.46 ± 0.36 versus 1.64 ± 0.44; p = 0.02). The number of segments with perfusion defects on RTMPE was similar in therapy and control group at 72 hours (5.92 ± 3.47 versus 6.94 ± 3.39; p = 0.15), but it was lower in the therapy group at 6 months (4.64 ± 3.31 versus 6.57 ± 4.29; p = 0.01). Conclusion Sonothrombolysis in patients with STEMI resulted in improved wall motion and ventricular perfusion scores over time.

10.
مقالة ي صينى | WPRIM | ID: wpr-932390

الملخص

Objective:To evaluate the feasibility and applicability of using phospholipid-hybridization method for preparing biomimetic microbubbles (Bio-MBs) ultrasound contrast agents.Methods:Leukocyte biomimetic microbubbles (MB leu), platelet biomimetic microbubbles (MB pla) and erythrocyte biomimetic microbubbles (MB ery) were prepared by multiple steps: film-hydration, phospholipid-hybridization, mechanical oscillation. The size and zeta potential of Bio-MBs were measured by dynamic light scattering. A laser scanning confocal microscopy experiment was performed to confirm the presence of membrane proteins on the shell of Bio-MBs. The fluorescence of FITC-labeled typical membrane protein was evaluated using a flow cytometer. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was used to characterize the membrane protein. Biosafety of Bio-MBs was evaluated by CCK-8 counting kit, blood and major organs. The contrast enhancement effect and stability were observed in vitro and in vivo. An in vivo fluorescence imaging system was performed to evaluate the distribution of Bio-MBs. The application value of biomimetic microbubbles was measured by ultrasound molecular imaging by using ischemia-reperfusion rat models and acute hepatitis rat models. Results:Bio-MBs with spherical shape distributed homogenously, without obvious aggregation. The membrane proteins were successfully integrated into the shell of Bio-MBs.The diameter of three Bio-MBs was similar to that of control microbubbles (MB con) ( P>0.05), three Bio-MBs had a lower zeta potential than MB con ( P<0.05). The Bio-MBs had an appreciable performance in vitro and in vivo biosafety. The Bio-MBs retained the main proteins inherited from cell membrane. Contrast enhanced ultrasound imaging in vitro and in vivo showed that the Bio-MBs had a stable imaging ability.MB leu and MB pla have good targeted imaging effect in two disease models. Conclusions:A series of Bio-MBs ultrasound contrast agents, which have high stability, biosafety and targeted imaging efficiency, were successfully prepared by using phospholipid-hybridization method. This fabrication method for obtaining Bio-MBs can be applied to different clinical scenarios with different cell types in the future.

11.
Chinese Journal of Ultrasonography ; (12): 1077-1083, 2022.
مقالة ي صينى | WPRIM | ID: wpr-992798

الملخص

Objective:To explore the capability of vascular endothelial growth factor receptor 2 (VEGFR2)/integrinα vβ 3 dual-targeted microbubbles in assessing the expression level of pro-angiogenic factors during renal cell carcinoma (RCC) growth. Methods:VEGFR2/integrinα vβ 3 dual-targeted microbubbles were prepared by using biotin-avidin linkage method. Twenty subcutaneous RCC xenografts in nude mice were established by subcutaneously injecting 786-O cells and then divided into 2 groups randomly. The targeted contrast-enhanced ultrasound (t-CEUS) examination was performed for all 10 mice in the first group when xenograft tumors were metered from 5 to 10 mm and >10 to 20 mm respectively. And the quantitative parameters of RCC on t-CEUS were longitudinally evaluated during tumor growth. The second group were divided into two subgroups according to xenograft tumors′ diameter, which was 5 to 10 mm and >10 to 20 mm respectively, and underwent t-CEUS examination. Quantitative analysis was performed for all t-CEUS images to obtain the targeted quantitative parameters, which including peak intensity (PI), area under the time-intensity curve (AUC), the differential tissue enhancement (dTE, presenting the difference in PI before (P 1) and after (P 2) the process of Flash). All xenograft tumors in the second group were harvested for immunohistochemical staining to observe the expression of VEGFR2, integrinα vβ 3 and CD31, and their differences in RCC with different tumor sizes. And the correlations between quantitative parameters and VEGFR2, integrinα vβ 3 and CD31 were analyzed. Results:The longitudinal comparison showed that there were statistically significant differences between AUC and dTE of RCC with different tumor sizes (all P<0.001). The larger the tumor size, the smaller the parameters were. According to the horizontal comparison, the expression levels of VEGFR2 and integrinα vβ 3 in larger RCCs were higher than those of RCCs with smaller size (both P<0.05), but there was no significant difference in CD31 expression between the two subgroups ( P=0.754). Both the targeted quantitative parameters (AUC anddTE ) and pro-angiogenic factors (VEGFR2 and integrinα vβ 3) were negatively correlated with tumor size ( rs=-0.83, -0.81, -0.70, -0.88; all P<0.05). Further more, there were good positive correlations between AUC and VEGFR2, integrinαvβ ( rs=0.76, 0.72; all P<0.05). There were good positive correlations between dTE and VEGFR2, integrinα vβ 3 ( rs=0.81, 0.70; all P<0.05). Additionally, the parameter PI was positively correlated with the expression of CD31 ( rs=0.70, P=0.025). Conclusions:The t-CEUS, mediated by VEGFR/integrinα vβ 3 dual-targeted microbubbles, allows noninvasive assessment of the expression levels of VEGFR2 and integrinα vβ 3 in RCCs, which decrease gradually with the increase of tumor size.

12.
Radiol. bras ; 54(5): 321-328, Sept.-Oct. 2021. graf
مقالة ي الانجليزية | LILACS-Express | LILACS | ID: biblio-1340580

الملخص

Abstract Although contrast-enhanced ultrasound has been shown to provide considerable benefits, particularly in pediatric patients, it is still used relatively rarely in Brazil. It has proven to be a safe technique, and adverse effects are rare. In this review, we address the technique and main applications of contrast-enhanced ultrasound in the pediatric population, including the evaluation of focal liver lesions, abdominal trauma, kidney grafts, liver grafts, bowel loops, and vesicoureteral reflux. It is important for pediatric radiologists to be acquainted with this promising tool, understanding its applications and limitations.


Resumo A ultrassonografia com contraste de microbolhas é um método ainda pouco utilizado no Brasil, mas que tem grandes vantagens, ainda mais na faixa pediátrica, como ausência de radiação e dispensa de sedação/anestesia. O contraste de microbolhas tem se mostrado bastante seguro e com raríssimas reações adversas graves. Apresentaremos nesta revisão a técnica para o uso desse contraste na ultrassonografia, bem como as principais aplicações na faixa pediátrica, como avaliação das lesões hepáticas focais, do trauma abdominal, do enxerto hepático e renal nos transplantes, das alças intestinais e da pesquisa de refluxo vesicoureteral. É importante que radiologistas que exerçam funções em centros pediátricos conheçam essa ferramenta promissora.

13.
Eng. sanit. ambient ; 26(5): 865-876, set.-out. 2021. tab, graf
مقالة ي البرتغالية | LILACS-Express | LILACS | ID: biblio-1346009

الملخص

RESUMO Este artigo apresenta estudos de coagulação, floculação e flotação por ar dissolvido que foram conduzidos com o objetivo de promover a clarificação de águas de lavagens de filtros (ALF) em uma estação de tratamento de água (ETA) com base em experimentos de bancada e piloto. A efetividade da coagulação-floculação foi analisada pela flotabilidade dos agregados obtidos sob diferentes níveis de pH e dosagem de cloreto de polialumínio, enquanto ensaios de flotação foram investigados com base na eficiência de saturação em bancada e na taxa de recirculação. Os resultados indicaram que o pH e a concentração do coagulante representaram condições críticas na etapa de coagulação. A variação do pH da ALF condicionada com 8 mg.L-1 de Al+3 destacou a formação de espécies hidrolisáveis e a elevada atividade das cargas dos coloides indicou a ocorrência de mecanismos diferentes da neutralização de cargas na coagulação. A máxima clarificação da água ocorreu com dosagem de 12 mg.L-1 de Al+3, razão de recirculação de 10%, tempo de floculação de 15 min e pH 6,5. Em configuração otimizada, a técnica alcançou remoção de 88% de turbidez e 86% de sólidos totais, o que pode resultar em mais de 11 quilogramas de sólidos removidos do sistema de tratamento em cada ciclo de lavagem em comparação com a sedimentação, implicando aumento de 33% da carreira de filtração e, consequentemente, redução de custos e melhor desempenho da estação.


ABSTRACT This article presents studies on coagulation, flocculation and dissolved air flotation that were conducted with the aim of promoting the clarification of spent filter backwash water (SFBW) in a Water Treatment Plant (WTP) based on bench and pilot experiments. The effectiveness of coagulation-flocculation was analyzed according to the buoyancy of the aggregates obtained from different levels of pH and dosage of polyaluminium chloride, whereas flotation tests were investigated based on bench saturation efficiency and recirculation rate. According to the results, the pH and the concentration of the coagulant represented critical conditions in the coagulation. The pH variation of the SFBW conditioned with 8 mg.L-1 of Al + 3 highlighted the formation of hydrolyzable species, and the high activity of the colloid indicated the occurrence of different mechanisms for neutralization in the coagulation. The maximum clarification of the SFBW occurred with a dosage of 12 mg.L-1 of Al+3, recirculation rate of 10%, flocculation time of 15 min, and pH 6.5. In an optimized configuration, the technique achieved removal of 88% turbidity and 86% total solids, which can result in more than 11 kilograms of solids removed from the WTP in each backwashing cycle compared with sedimentation. This would imply an increase of 33% in the backwashing interval and, consequently, in the reduction of costs and in the better performance of the WTP.

14.
Acta Pharmaceutica Sinica ; (12): 761-770, 2021.
مقالة ي صينى | WPRIM | ID: wpr-876524

الملخص

Blood-brain barrier (BBB) is the most challengeable obstacle for brain-targeted drug delivery. The combination of focused ultrasound (FUS) and microbubbles provides a new way for brain-targeted drug delivery across BBB based on the cavitation effect. This review briefly described the recent research of FUS combined with microbubbles to enhance the BBB permeability for brain-targeted drug delivery. The contents included the FUS mechanism, the types of the commercial microbubbles, shell materials, inner gas and preparation techniques of microbubbles, the opening mechanism of FUS with microbubbles, and the safety consideration. FUS combined with microbubbles may be the effective strategy to improve the BBB permeability for brain-targeted delivery, which could provide references for the clinical applications.

15.
J. vasc. bras ; 20: e20200093, 2021. tab, graf
مقالة ي البرتغالية | LILACS | ID: biblio-1346433

الملخص

Resumo Contexto O ultrassom contrastado por microbolhas (CMUS) é uma modalidade diagnóstica de acurácia bem demonstrada por estudos internacionais para seguimento de reparo endovascular do aneurisma de aorta abdominal (EVAR). Não existem, no entanto, estudos nacionais focados nesse método de seguimento. Objetivos O objetivo deste estudo foi relatar a experiência inicial com CMUS em um hospital terciário, traçando uma comparação dos achados do CMUS com o ultrassom Doppler convencional (USGD), com o intuito de verificar se a adição de contraste ao protocolo padrão de controle ultrassonográfico incorreu alteração nos achados. Métodos Entre 2015 e 2017, 21 pacientes em seguimento de EVAR foram submetidos ao USGD seguido de CMUS. Foram avaliados os achados de exame referentes à identificação de complicações, bem como à capacidade de identificação da origem da endofuga. Resultados Entre os 21 casos avaliados, 10 complicações foram evidenciadas no total: sete pacientes apresentaram endofuga (33,3%); dois pacientes apresentaram estenose em ramo de endoprótese (9,52%); e um paciente apresentou dissecção em artéria ilíaca externa (4,76%). Em 21 pacientes avaliados, o uso combinado dos métodos identificou 10 casos de complicações pós-EVAR. Em seis dos sete casos de endofugas (85,71%), o uso dos métodos combinados foi capaz de identificar a origem. O USGD isolado falhou na identificação da endofuga em dois casos (28,5%), identificando achados duvidosos em outros dois casos (28,5%), que obtiveram definição diagnóstica após associação do CMUS. Conclusões O CMUS é uma técnica de fácil execução, a qual adiciona subsídios ao seguimento de EVAR infrarrenal.


Abstract Background Microbubble contrast enhanced ultrasound (CEUS) is an accurate diagnostic method for follow-up after endovascular abdominal aortic aneurysm repair (EVAR) that has been well-established in international studies. However, there are no Brazilian studies that focus on this follow-up method. Objectives The objective of this study was to report initial experience with CEUS at a tertiary hospital, comparing the findings of CEUS with those of conventional Doppler ultrasound (DUS), with the aim of determining whether addition of contrast to the standard ultrasonographic control protocol resulted in different findings. Methods From 2015 to 2017, 21 patients in follow-up after EVAR underwent DUS followed by CEUS. The findings of these examinations were analyzed in terms of identification of complications and their capacity to identify the origin of endoleaks. Results There was evidence of complications in 10 of the 21 cases examined: seven patients exhibited endoleaks (33.3%); two patients exhibited stenosis of a branch of the endograft (9.52%); and one patient exhibited a dissection involving the external iliac artery (4.76%). In the 21 patients assessed, combined use of both methods identified 10 cases of post-EVAR complications. In six of the seven cases of endoleaks (85.71%), use of the methods in combination was capable of identifying the origin of endoleakage. DUS alone failed to identify endoleaks in two cases (28.5%) and identified doubtful findings in another two cases (28.5%), in which diagnostic definition was achieved after employing CEUS. Conclusions CEUS is a technique that is easy to perform and provides additional support for follow-up of infrarenal EVAR.


الموضوعات
Humans , Male , Aged , Aged, 80 and over , Aortic Aneurysm, Abdominal/surgery , Ultrasonography, Doppler/instrumentation , Contrast Media , Microbubbles , Endovascular Procedures , Follow-Up Studies , Aortic Aneurysm, Abdominal/rehabilitation , Aortic Aneurysm, Abdominal/diagnostic imaging , Ultrasonography, Doppler/methods
16.
مقالة ي الانجليزية | LILACS-Express | LILACS, VETINDEX | ID: biblio-1487655

الملخص

ABSTRACT: The objective of this study was to verify the applicability of B-mode ultrasonography, ARFI elastography and CEUS in the diagnosis of chronic kidney disease and its Stages in dogs. 24 healthy dogs and 28 with CKD were included. In B-mode, the echogenicity, echotexture and cortico-medullary ratio of the kidneys were verified. By elastography, the shear-wave velocity of the cortical (SWVcort) and medullary (SWVmed) regions were determined and tissue deformity was evaluated. Wash-in, wash-out and peak enhancement (TPic) of the contrast in the renal parenchyma were calculated and homogeneity, presence of filling gaps and distinction of filling phases were evaluated by CEUS. Changes in echogenicity, echotexture and cortico-medullary ratio were observed only in sick patients. There was an increase in SWVcort in CKD, with a cutoff point >2.91m/s. Healthy kidneys were non-deformable and 25% had changes in gray scales. There was an increase in wash-in and TPic, changes in filling characteristics, filling failures and difficulty in distinguishing between the Stages in CEUS in CKD. It was found that dogs with CKD 2, 3 and 4 had greater SWVcort and wash-in values than CKD 1. Elastographic and CEUS changes were observed in dogs with CKD, demonstrating the applicability of ultrasonographic techniques in their diagnosis.


RESUMO: O objetivo deste estudo foi verificar a aplicabilidade da ultrassonografia modo-B, elastografia ARFI e CEUS no diagnóstico da doença renal crônica e seus estágios em cães. Foram incluídos 24 cães saudáveis e 28 com DRC. Pelo modo-B, verificou-se ecogenicidade, ecotextura e relação córtico-medular dos rins. Pela elastografia, foram determinadas as velocidades de cisalhamento das regiões cortical (SWVcort) e medular (SWVmed) e foi avaliada a deformidade tecidual. Calculou-se os temos de wash-in, wash-out e pico de intensidade (TPic) do parênquima renal e avaliou-se homogeneidade, presença de falhas e distinção das fases de preenchimento por contraste por meio de CEUS. Alterações em ecogenicidade, ecotextura e relação córtico-medular foram observadas somente em pacientes doentes. Houve aumento da SWVcort na DRC, com ponto de corte >2.91m/s. Rins saudáveis foram não-deformáveis e 25% apresentou alterações nas escalas de cinza. Houve aumento do wash-in e TPic, alterações nas características de preenchimento, falhas e dificuldade para distinguir as fases de preenchimento do contraste nos rins com DRC. Verificou-se que cães com DRC graus 2, 3 e 4 tiveram valores de SWVcort e wash-in maiores que cães com DRC grau 1. Foram obsrervadas alterações elastográfica e de CEUS em cães com DRC, demonstrando a aplicabilidade destas técnicas ultrassonográficas no seu diagnóstico.

17.
Pesqui. vet. bras ; 41: e06785, 2021. tab, ilus
مقالة ي الانجليزية | LILACS, VETINDEX | ID: biblio-1250490

الملخص

The objective of this study was to verify the applicability of B-mode ultrasonography, ARFI elastography and CEUS in the diagnosis of chronic kidney disease and its Stages in dogs. 24 healthy dogs and 28 with CKD were included. In B-mode, the echogenicity, echotexture and cortico-medullary ratio of the kidneys were verified. By elastography, the shear-wave velocity of the cortical (SWVcort) and medullary (SWVmed) regions were determined and tissue deformity was evaluated. Wash-in, wash-out and peak enhancement (TPic) of the contrast in the renal parenchyma were calculated and homogeneity, presence of filling gaps and distinction of filling phases were evaluated by CEUS. Changes in echogenicity, echotexture and cortico-medullary ratio were observed only in sick patients. There was an increase in SWVcort in CKD, with a cutoff point >2.91m/s. Healthy kidneys were non-deformable and 25% had changes in gray scales. There was an increase in wash-in and TPic, changes in filling characteristics, filling failures and difficulty in distinguishing between the Stages in CEUS in CKD. It was found that dogs with CKD 2, 3 and 4 had greater SWVcort and wash-in values than CKD 1. Elastographic and CEUS changes were observed in dogs with CKD, demonstrating the applicability of ultrasonographic techniques in their diagnosis.(AU)


O objetivo deste estudo foi verificar a aplicabilidade da ultrassonografia modo-B, elastografia ARFI e CEUS no diagnóstico da doença renal crônica e seus estágios em cães. Foram incluídos 24 cães saudáveis e 28 com DRC. Pelo modo-B, verificou-se ecogenicidade, ecotextura e relação córtico-medular dos rins. Pela elastografia, foram determinadas as velocidades de cisalhamento das regiões cortical (SWVcort) e medular (SWVmed) e foi avaliada a deformidade tecidual. Calculou-se os temos de wash-in, wash-out e pico de intensidade (TPic) do parênquima renal e avaliou-se homogeneidade, presença de falhas e distinção das fases de preenchimento por contraste por meio de CEUS. Alterações em ecogenicidade, ecotextura e relação córtico-medular foram observadas somente em pacientes doentes. Houve aumento da SWVcort na DRC, com ponto de corte >2.91m/s. Rins saudáveis foram não-deformáveis e 25% apresentou alterações nas escalas de cinza. Houve aumento do wash-in e TPic, alterações nas características de preenchimento, falhas e dificuldade para distinguir as fases de preenchimento do contraste nos rins com DRC. Verificou-se que cães com DRC graus 2, 3 e 4 tiveram valores de SWVcort e wash-in maiores que cães com DRC grau 1. Foram obsrervadas alterações elastográfica e de CEUS em cães com DRC, demonstrando a aplicabilidade destas técnicas ultrassonográficas no seu diagnóstico.(AU)


الموضوعات
Animals , Dogs , Congenital Abnormalities , Ultrasonography , Renal Insufficiency, Chronic , Elasticity Imaging Techniques , Perfusion , Kidney
19.
مقالة ي صينى | WPRIM | ID: wpr-860929

الملخص

Objective: To observe the value of targeted contrast enhanced ultrasound (CEUS) using anti-Mullerian canal hormone (AMH) targeted nanobubbles (AMH-NB) for in vivo quantitative evaluation on ovarian neovascular density after ovarian auto-transplantation in SD rats. Methods: The nanobubbles carrying anti-AMH antibody were prepared, and their basic physical properties were examined. Then ovarian auto-transplantation rat models were established. The targeted (AMH-NB), non-targeted (N-NB) contrast agents and SonoVue were administered on the 7th day after transplantation to obtain peak intensity (PI) and time to peak (TTP). The microvascular density (MVD) was measured using immunohistochemistry, and the correlation of PI, TTP and MVD were analyzed. Results: The particle size of AMH-NB uniformly distributed, ranged (622.67±33.65)nm, and the concentration of AMH-NB was (2.90±0.26)×108/ml. PI of ovarian angiography with AMH-NB was (7.93±0.65)dB and TTP was (42.53±1.74)s, with N-NB was (6.14±0.44)dB and (54.35±1.73)s, with Sonovue was (4.15±0.83)dB and (28.71±1.18)s, respectively (all P<0.05).Immunohistochemical analysis showed that the microvascular density was (61.20±6.84)/HP, histological analysis indicated that AMH-NB were able to penetrate blood vessels to the interstitial space and combine with AMH. PI, TTP of AMH-NB were highly both correlated with MVD (r=0.84, r=-0.84, both P<0.05). Conclusion: AMH-NB can be used to qualitatively and quantitatively evaluate the angiogenesis in transplanted ovarian of rats in vivo with CEUS.

20.
مقالة ي صينى | WPRIM | ID: wpr-845211

الملخص

Because of the blood-brain barrier (BBB)and the lack of significant enhancement method for the drug penetration into and retention in brain, effective methods and drugs for the treatment of brain diseases are extremely limited. Ultrasound can effec tively, safely and reversibly open the BBB and thus is an ideal method for the targeted, non-invasive drug entry into the intracranial tis sue, which has been expected to become a new means for treating brain diseases in the near future. Following a brief introduction of some biological characteristics of brain, this review elaborates the mechanisms of the ultrasound combining microbubbles(USMB)for brain targeted drug delivery, including the opening of the tight junction, stimulation of endocytosis, inhibition of multidrug resistance protein expression, enhancement of drug concentration in target area, extension of the residence time, and adjustment of the intersti tial pressure in target tissue. Then, the application of ultrasound in the treatment of some diseases including the Alzheimer's disease (AD), Huntington's disease(HD), Parkinson's disease(PD), and brain tumors are summarized, and the existing problems in the ul trasound therapy are also discussed, in order to provide a valuable reference for further improvement in the treatment of brain diseases.

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