Objective:To assess the clinical utility of vector flow mapping（VFM）for evaluating left ventricular wall shear stress（WSS）in individuals with non-obstructive hypertrophic cardiomyopathy（nHCM）.Methods:Forty patients with non-obstructive HCM（nHCM）and 46 healthy volunteers in Tangdu Hospital of Air Force Medical University from May 2020 to September 2023 were enrolled prospectively in this study. The left ventricular WSS of each of 18 segments was measured and analyzed by VFM during rapid filling phase（T1），slow filling phase（T2），isovolumetric contraction phase（T3）and rapid ejection phase（T4）.Results:① WSS decreased gradually from basal to apical segments in control group，while there was no such change pattern in nHCM group. ② Diastolic phase：When compared to the control group，the nHCM group demonstrated significantly increased WSS across all segments of the inferoseptal regions，the basal anteroseptal segment，and the middle and apical inferior segments during the T1 stage. Additionally，at the T2 stage，the WSS was significantly higher in the nHCM group across all segments of the inferoseptal and anteroseptal regions，the basal anterolateral segment，and the apical inferolateral and anterior segments（all P<0.05）. Conversely，during the T1 stage，the basal anterolateral segment，basal inferolateral segment，and the middle and apical anteroseptal segments，as well as during the T2 stage，the basal and middle inferior segments，exhibited lower WSS values compared to the control group，with these differences being statistically significant（all P<0.05）. ③Systolic Phase：During the T3 stage，the WSS values in all segments of the anteroseptal and anterolateral regions，as well as the apical inferior and anterior segments，were significantly elevated in the nHCM group compared to the control group（all P<0.05）.At the T4 stage，WSS in each segment of the inferolateral and inferior regions，as well as the basal and middle anterior segments，was significantly elevated in the nHCM group compared to the control group（all P<0.01）. Conversely，during the same stage，the WSS values in the basal inferolateral segment，the basal and middle anterolateral segments，and the basal and middle anteroseptal segments were significantly lower in the nHCM group than in the control group，with all differences reaching statistical significance（all P<0.01）.Regarding global WSS，the left ventricular global WSS in the nHCM group was significantly higher than that in the control group at both the T2 and T3 stages（all P<0.001）. Furthermore，the global WSS at the T3 stage was negatively correlated with left ventricular end-systolic volume，end-diastolic volume，and left ventricular stroke volume（ r=-0.226， P=0.036； r=-0.345， P=0.001； r=-0.303， P=0.005）. Conclusions:Significant differences in WSS are observed between patients with nHCM and control groups at various phases. WSS may serve as an early indicator of changes in cardiac function in nHCM patients.

Objective:Multi-facial reflective type of nano-ultrasound contrast agents（UCAs）loaded with hollow self-decomposable silica nanoparticles（SiO 2 NP）of different particle sizes were prepared to investigate the effect of the particle size of SiO 2 NP on the structural and physicochemical characteristics of the nano-UCAs，as well as on the intensity of ultrasound contrast. Methods:Two types of SiO 2 NP with large and small particle sizes（SiO 2 NP L and SiO 2 NP S）were prepared by adjusting the material ratios，and nano-UCAs with different particle sizes of SiO 2 NP S loaded at a concentration of 2 mg/ml were prepared by the thin film hydration method（SiO 2 NP L@NBs and SiO 2 NP S@NBs），and compared with the commercial SonoVue and the prepared nano-bubbles（NBs）for comparing the particle size，zeta potential and stability，scanning electron microscopy to observe the structure，CCK8 method to assess cytotoxicity，and comparison of ultrasonography imaging intensity in in vivo and in vitro experiments. Results:The particle sizes of the two SiO 2 NP（SiO 2 NP L and SiO 2 NP S）were（213.270 ± 16.890）nm and（53.870 ± 8.246）nm，respectively，and the particle size of the synthesized nano-UCA was SiO 2 NP L@NBs（628.40 ± 89.97）nm and SiO 2 NP S@NBs（493.40 ± 36.35）nm respectively，there was no difference in particle size（ P>0.05）. The scanning electron microscope showed a "fig" structure. The stability of SiO 2 NP S@NBs was better than that of SiO 2 NP L@NBs and SonoVue. Safety tests showed that both SiO 2 NP L@NBs and SiO 2 NP S@NBs were safe and usable. Compared with NBs，the intensity of contrast-enhanced ultrasound contrast in SiO 2 NP@NBs with multiple reflection interfaces was significantly enhanced，and the enhanced intensity of contrast-enhanced ultrasound in vitro and in vivo in the SiO 2 NP L@NBs group was significantly higher than that of the NBs group，the SiO 2 NP S@NBs group，and the SonoVue group（all P<0.05）. There was no significant difference in the enhanced intensity of in vitro contrast-enhanced ultrasound between the SiO 2 NP S@NBs group and that of SonoVue（ P>0.05），and the enhanced intensity of contrast-enhanced ultrasound in vivo was significantly higher than that in the SonoVue group（ P<0.05）. Conclusions:The large and small SiO 2 NPs prepared by adjusting the material ratio do not affect the nanoparticle size of UCA.The ultrasonic enhancement ability of nano-UCA with large particle size SiO 2 NP is stronger，but the stability time at room temperature is shorter than that of nano-UCA with small particle size SiO 2 NP.

Objective:To assess the clinical utility of vector flow mapping（VFM）for evaluating left ventricular wall shear stress（WSS）in individuals with non-obstructive hypertrophic cardiomyopathy（nHCM）.Methods:Forty patients with non-obstructive HCM（nHCM）and 46 healthy volunteers in Tangdu Hospital of Air Force Medical University from May 2020 to September 2023 were enrolled prospectively in this study. The left ventricular WSS of each of 18 segments was measured and analyzed by VFM during rapid filling phase（T1），slow filling phase（T2），isovolumetric contraction phase（T3）and rapid ejection phase（T4）.Results:① WSS decreased gradually from basal to apical segments in control group，while there was no such change pattern in nHCM group. ② Diastolic phase：When compared to the control group，the nHCM group demonstrated significantly increased WSS across all segments of the inferoseptal regions，the basal anteroseptal segment，and the middle and apical inferior segments during the T1 stage. Additionally，at the T2 stage，the WSS was significantly higher in the nHCM group across all segments of the inferoseptal and anteroseptal regions，the basal anterolateral segment，and the apical inferolateral and anterior segments（all P<0.05）. Conversely，during the T1 stage，the basal anterolateral segment，basal inferolateral segment，and the middle and apical anteroseptal segments，as well as during the T2 stage，the basal and middle inferior segments，exhibited lower WSS values compared to the control group，with these differences being statistically significant（all P<0.05）. ③Systolic Phase：During the T3 stage，the WSS values in all segments of the anteroseptal and anterolateral regions，as well as the apical inferior and anterior segments，were significantly elevated in the nHCM group compared to the control group（all P<0.05）.At the T4 stage，WSS in each segment of the inferolateral and inferior regions，as well as the basal and middle anterior segments，was significantly elevated in the nHCM group compared to the control group（all P<0.01）. Conversely，during the same stage，the WSS values in the basal inferolateral segment，the basal and middle anterolateral segments，and the basal and middle anteroseptal segments were significantly lower in the nHCM group than in the control group，with all differences reaching statistical significance（all P<0.01）.Regarding global WSS，the left ventricular global WSS in the nHCM group was significantly higher than that in the control group at both the T2 and T3 stages（all P<0.001）. Furthermore，the global WSS at the T3 stage was negatively correlated with left ventricular end-systolic volume，end-diastolic volume，and left ventricular stroke volume（ r=-0.226， P=0.036； r=-0.345， P=0.001； r=-0.303， P=0.005）. Conclusions:Significant differences in WSS are observed between patients with nHCM and control groups at various phases. WSS may serve as an early indicator of changes in cardiac function in nHCM patients.

Objective:Multi-facial reflective type of nano-ultrasound contrast agents（UCAs）loaded with hollow self-decomposable silica nanoparticles（SiO 2 NP）of different particle sizes were prepared to investigate the effect of the particle size of SiO 2 NP on the structural and physicochemical characteristics of the nano-UCAs，as well as on the intensity of ultrasound contrast. Methods:Two types of SiO 2 NP with large and small particle sizes（SiO 2 NP L and SiO 2 NP S）were prepared by adjusting the material ratios，and nano-UCAs with different particle sizes of SiO 2 NP S loaded at a concentration of 2 mg/ml were prepared by the thin film hydration method（SiO 2 NP L@NBs and SiO 2 NP S@NBs），and compared with the commercial SonoVue and the prepared nano-bubbles（NBs）for comparing the particle size，zeta potential and stability，scanning electron microscopy to observe the structure，CCK8 method to assess cytotoxicity，and comparison of ultrasonography imaging intensity in in vivo and in vitro experiments. Results:The particle sizes of the two SiO 2 NP（SiO 2 NP L and SiO 2 NP S）were（213.270 ± 16.890）nm and（53.870 ± 8.246）nm，respectively，and the particle size of the synthesized nano-UCA was SiO 2 NP L@NBs（628.40 ± 89.97）nm and SiO 2 NP S@NBs（493.40 ± 36.35）nm respectively，there was no difference in particle size（ P>0.05）. The scanning electron microscope showed a "fig" structure. The stability of SiO 2 NP S@NBs was better than that of SiO 2 NP L@NBs and SonoVue. Safety tests showed that both SiO 2 NP L@NBs and SiO 2 NP S@NBs were safe and usable. Compared with NBs，the intensity of contrast-enhanced ultrasound contrast in SiO 2 NP@NBs with multiple reflection interfaces was significantly enhanced，and the enhanced intensity of contrast-enhanced ultrasound in vitro and in vivo in the SiO 2 NP L@NBs group was significantly higher than that of the NBs group，the SiO 2 NP S@NBs group，and the SonoVue group（all P<0.05）. There was no significant difference in the enhanced intensity of in vitro contrast-enhanced ultrasound between the SiO 2 NP S@NBs group and that of SonoVue（ P>0.05），and the enhanced intensity of contrast-enhanced ultrasound in vivo was significantly higher than that in the SonoVue group（ P<0.05）. Conclusions:The large and small SiO 2 NPs prepared by adjusting the material ratio do not affect the nanoparticle size of UCA.The ultrasonic enhancement ability of nano-UCA with large particle size SiO 2 NP is stronger，but the stability time at room temperature is shorter than that of nano-UCA with small particle size SiO 2 NP.

Purpose To prepare biomimetic targeted nanobubbles(NBs)named IR780-RBCM@NBs and explore the ability of performing ultrasound enhancement,escaping immune surveillance and targeting tumor cells.Materials and Methods The red blood cell membrane(RBCM)was extracted from mouse blood,the IR780-RBCM@NBs were prepared by modified membrane hydration method,the physical and chemical properties of nanobubbles were detected.In vitro,self-made equipment was used to test the contrast-enhanced ultrasound imaging ability of the nanobubbles.Laser confocal fluorescence microscopy was used to observe the characteristics of the nanobubbles retaining CD47 on the RBCM surface,and further to observe the phagocytosis of the nanobubbles by macrophages and the targeting ability of the nanobubbles to different tumor cells.Results The newly prepared IR780-RBCM@NBs had the appearance of emulsion,the particle size was about(522.4±58.6)nm and the dispersity was good.It was spherical in uniform size under the microscope.IR-780 could be detected on the nanobubbles,which had the dual-mode imaging capabilities of near-infrared fluorescence imaging and contrast-enhanced ultrasound imaging.The RBCM-specific protein CD47 could be detected on the surface of the nanobubbles.The nanobubbles exhibited excellent immune phagocytic escape function and high efficiency to target different tumor cells.Conclusion Newly prepared biomimetic targeted IR780-RBCM@NBs,with good performance,can escape immune phagocytosis and efficiently target tumors,providing a new idea for molecular targeted accurate diagnosis and treatment of tumors.

Objective:To evaluate the performance of the self-developed transcranial ultrasound patch probe as well as its stability and safety in clinical applications.Methods:This study was a cross-sectional study. Fifty healthy subjects in Tangdu Hospital from October to December 2023 were randomly and equally divided into two groups using a simple randomization method. The transcranial Doppler ultrasound (TCD) examinations were performed using the self-developed transcranial ultrasound patch probe and normal TCD probe alternatively in each group from squatting to sitting and then to standing posture. Two experienced sonographers (A, B) each completed one test for the same subject using the above two different probes. The differences of the ultrasound parameters of middle cerebral artery (MCA) blood flow measured by the self-developed transcranial ultrasound patch probe and the normal TCD probe in different postures (squatting, sitting, standing) were compared. At the same time, operator satisfaction with the use of the two probes was assessed in terms of time taken to obtain satisfactory images, operational comfort, and ease of handling. In addition, the subject's comfort during the examination was examined, and the signal acquisition stability of the two probes was comprehensively evaluated.Results:There was no significant difference in detection of various ultrasound parameters of MCA between using the transcranial patch probe and the normal TCD probe (all P>0.05). The overall satisfaction of transcranial ultrasound patch probe and normal TCD probe was quite similar. The transcranial ultrasound patch probe acquired favorable and stable signals. No subjects experienced adverse events/accidents during the examination of the subjects using the transcranial ultrasound patch probe as well as the normal TCD probe.Both probes had good and stable signal acquisition. Conclusions:TCD examinations could be well performed using the transcranial ultrasound patch probe, which might provide a potential new method for real-time monitoring and evaluating of cerebral blood flow of a moving subject.

Background: Gut microbiota is closely related to the occurrence and development of diabetes and affects the prognosis of diabetic complications, and the underlying mechanisms are only partially understood. We aimed to explore the possible link between the gut microbiota and vascular inflammation of diabetic mice. Methods: The db/db diabetic and wild-type (WT) mice were used in this study. We profiled gut microbiota and examined the and vascular function in both db/db group and WT group. Gut microbiota was analyzed by 16s rRNA sequencing. Vascular function was examined by ultrasonographic hemodynamics and histological staining. Clostridium butyricum (CB) was orally administered to diabetic mice by intragastric gavage every 2 days for 2 consecutive months. Reactive oxygen species (ROS) and expression of nuclear factor erythroid-derived 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were detected by fluorescence microscopy. The mRNA expression of inflammatory cytokines was tested by quantitative polymerase chain reaction. Results: Compared with WT mice, CB abundance was significantly decreased in the gut of db/db mice, together with compromised vascular function and activated inflammation in the arterial tissue. Meanwhile, ROS in the vascular tissue of db/db mice was also significantly increased. Oral administration of CB restored the protective microbiota, and protected the vascular function in the db/db mice via activating the Nrf2/HO-1 pathway. Conclusion This study identified the potential link between decreased CB abundance in gut microbiota and vascular inflammation in diabetes. Therapeutic delivery of CB by gut transplantation alleviates the vascular lesions of diabetes mellitus by activating the Nrf2/HO-1 pathway.

Objective:To explore the level of arterial stiffness and its influencing factors in prediabetic population.Methods:From June 2021 to June 2022, 207 prediabetes patients were prospectively and randomly recruited from the physical examination center and outpatient clinic of Tangdu Hospital of Air Force Military Medical University to be the prediabetic group and 130 healthy volunteers at the same time with the same gender and age as the healthy controls. The carotid-femoral pulse wave velocity (PWV), brachial-radial PWV, and femoral-ankle PWV were measured by an automatic ultrasonic arterial stiffness measurement technology. The common carotid artery wall intima-media thickness (IMT) and left heart function were routinely evaluated. A questionnaire was designed to investigate the subjects′ smoking, drinking, diet, staying up late, exercise and other living habits. Comparison between groups and multivariate linear regression analysis were used to analyze the relevant data.Results:The carotid-femoral PWV and common carotid artery wall IMT in prediabetic group were significantly higher than those in healthy controls [(7.10±2.00)m/s vs (6.26±1.14)m/s, (0.57±0.11)mm vs (0.51±0.08)mm; both P<0.001], but there were no significant differences in the brachial-radial PWV and femoral-ankle PWV between the two groups (both P>0.05). Multivariate linear regression analysis showed that prediabetes was an independent influencing factor in carotid-femoral PWV after adjusting for confounding factors ( P<0.001), in addition, age ( P<0.001), diastolic blood pressure ( P<0.001), staying up late ( P=0.011) and low density lipoprotein cholesterol ( P=0.022) were also the independent influencing factors of carotid-femoral PWV. Conclusions:Compared with healthy people, the stiffness of aorta is significantly increased in prediabetic people, but there is no significant change in the stiffness of peripheral arteries. Prediabetes, age, diastolic blood pressure, staying up late and low density lipoprotein cholesterol are independent influencing factors of carotid-femoral PWV.

Objective:To investigate the effect of self-made phase-change nanodroplets IR780/FA-Nds-DTX as molecular targeted ultrasound contrast agents for accurate diagnosis and combined targeted therapy of pancreatic cancer.Methods:Pancreatic cancer cell lines were cultured in vitro and 50 tumor bearing nude mouse models were established. The experimental group (IR780/ FA-NdS-DTX) and four control groups[ normal saline, Nds(FITC), FA-Nds (FITC) and IR-780] were divided to verify dual-mode targeted imaging. The imaging using the IVIS Imaging System verified the high-efficiency targeted detection ability and near-infrared fluorescence imaging of IR780/FA-Nds-DTX for tumors in vivo, phase transformation induced by low-intensity focused ultrasound and further contrast-enhanced ultrasound imaging verified the high-efficiency aggregation of IR780/FA-Nds-DTX in local tumors and accurate evaluation of tumor contour. The therapeutic effect was observed in the experimental group (IR780/FA-Nds-DTX) and four control groups (FA-Nds-IR780, FA-Nds-DTX, FA-Nds and normal saline). After low-intensity focused ultrasound irradiation for 30s induced microbubble blasting after phase transformation in each group, 808nm photothermal therapy apparatus was used to irradiate tumor area in each group. Two-dimensional ultrasound was used to monitor the changes in tumor volume in each group before and at 3 d, 9 d, 15 d after treatment, and the changes in tumor volume rate and inhibition in each group were statistically analyzed and compared.Results:The amount of IR780/ FA-Nds-DTX locally targeted aggregation was the largest, and the average fluorescence intensity of tumor in the experimental group was significantly higher than that of the control groups: IR780/ FA-Nds-DTX group compared with Nds(FITC) group[(5.12±0.69)×10 7 vs (1.06±0.23)×10 7, P<0.05], IR780/FA-Nds-DTX group compared with FA-Nds (FITC) group [(5.12±0.69)×10 7 vs (2.98±0.34)×10 7, P<0.05], IR780/FA-Nds-DTX group compared with IR-780 group [(5.12±0.69)×10 7 vs (1.54±0.42)×10 7, P<0.05], and there was no fluorescence in tumor area in saline group. Further contrast-enhanced ultrasound imaging after nanodroplet phase transformation could more accurately locate the tumor boundary. After 15 days of photothermal ablation combined with chemotherapy, the growth rate of tumor volume in the IR780/ FA-Nds-DTX treatment group was significantly lower than that in the control groups: IR780/FA-Nds-DTX group compared with FA-Nds-IR780 group[(0.105±0.075) vs (0.405±0.175), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds-DTX group [(0.105±0.075) vs (1.385±0.035), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds group [(0.105±0.075) vs (2.255±0.105), P<0.05], IR780/ FA-Nds-DTX group compared with normal saline group [(0.105±0.075) vs (2.185±0.155), P<0.05]. And the tumor inhibition rate increased significantly: IR780/ FA-Nds-DTX group compared with FA-Nds-IR780 group [(0.93±0.06) vs (0.48±0.17), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds-DTX group [(0.93±0.06) vs (-0.51±0.105), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds group [(0.93±0.06) vs (-1.63±0.115), P<0.05], IR780/ FA-Nds-DTX group compared with normal saline[(0.93±0.06) vs (-1.35±0.245), P<0.05]. Conclusions:The self-made phase-change ultrasound contrast agents IR780/FA-Nds-DTX have good potential clinical value in targeted detection and combined therapy of pancreatic cancer with small lesions or even metastases.

Objective:To investigate the application of ultrasound imaging in evaluating the curative effect of patients with nutcracker syndrome (NCS) treated with three-dimensional(3D) printing extravascular titanium stents.Methods:From December 2015 to December 2018, a total of 41 NCS patients enrolled in the Second Affiliated Hospital of the Air Force Military Medical University to receive 3D-printing extravascular titanium stents treatment were included in this study. Ultrasound and CT angiography (CTA) were performed before and 1 week after operation to evaluate the compression of left renal vein and related hemodynamic changes.Results:Before the operative, the ultrasound examination showed that the angle between the abdominal aorta and superior mesenteric artery was (21.29±4.53)°, which was significantly improved in 1 week after treatment [(47.42±7.45)°, P<0.001]. Left renal vein was significantly compressed before treatment, with the smallest inner diameter of (1.51±0.49)mm and its peak blood flow velocity was (143.92±50.40)cm/s. Postoperative ultrasound images showed the significant expansion of left renal vein and no high velocity blood flow was observed. Ultrasound examination also showed that the diameter of left renal vein at renal hilum, blood flow velocity at renal hilum and inner diameter of spermatic vein were significantly improved after treatment ( P<0.001). Similar to ultrasound results, CTA also found that the angle between abdominal aorta and superior mesenteric artery increased significantly after treatment[(17.59±4.56)° vs (52.27±9.01)°, P<0.001]. CTA also showed the left renal vein was compressed before treatment, with the smallest inner diameter of (2.09±0.86)mm, and it was significantly expanded after operation. The inner diameter of left renal vein at renal hilum was also significantly reduced after treatment ( P<0.001). Conclusions:Ultrasound imaging can effectively evaluate the LRV compression and related hemodynamic changes before and after 3D printed stent implantation treatment in NCS patients and provide a reliable method to evaluate its clinical efficacy for these patients.