Optimal use of fielder XT guidewire enhances the success rate of chronic total occlusion percutaneous coronary intervention.

Background: Chronic total occlusion (CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-term survival. Although the success rate of CTO percutaneous coronary intervention (CTO-PCI) has improved, CTO-PCI remains technically challenging.

Differential Expression Pattern of Exosome Long Non-Coding RNAs (lncRNAs) and MicroRNAs (miRNAs) in Vascular Endothelial Cells Under Heat Stroke.

BACKGROUND Heat stroke is a life-threatening disease which is characterized by a high body temperature and multiple organ dysfunction syndrome. Vascular endothelial cell injury is a main feature of heat stroke. Little is known about the long noncoding RNA (lncRNA) and microRNA (miRNA) expression alternation in endothelial cell exosomes related to heat stroke.

Metastasis-associated in colon cancer-1 in gastric cancer: Beyond metastasis.

Metastasis-associated in colon cancer-1 (MACC1) is an oncogene that was first identified in colon cancer. The upstream and downstream of MACC1 form a delicate regulatory network that supports its tumorigenic role in cancers. Multiple functions of MACC1 have been discovered in many cancers.

[Effects of high and low shear stress on vascular remodeling and endothelial vascular cell adhesion molecular-1 expression in mouse abdominal aorta].

Objective: To establish a mouse model of abdominal aorta stenosis and analyze the alterations in the arterial wall response to high and low shear stress.

Methods: Twenty mouse were randomized equally into 4 groups, including 3 test groups (1, 7 and 14 day groups) with surgically induced stenosis of the abdominal aorta, and a sham-operated group without stenosis. The hemodynamics and the internal diameter of the blood vessel were measured by color Doppler flow imaging.

[Echocardiographic evaluation of pressure overload-induced cardiac remodeling in mice using different ultrasound machines].

Objective: To compare the results of echocardiographic evaluation of pressure overload-induced cardiac remodeling in mice using different ultrasound machines.

Methods: Eighteen C57 BL/6 mice were randomly divided into the sham-operated and the transverse aortic constriction (TAC) groups (n=9). Eight weeks after the operation, the cardiac function of TAC group was evaluated using Siemens ultrasonic instrument with 15L8 probe and the differences between the awake and anesthetized states were compared.

[Evaluation of tumor angiogenesis using microbubbles conjugated with RGD peptides and contrast enhanced ultrasound].

Objective: To assess the feasibility of usage of microbubbles conjugated with RGD peptides and contrast enhanced ultrasound (CEU) in detection of tumor angiogenesis.

Methods: Lipid microbubbles (MB) were prepared, and the RGD peptides were covalently conjugated to the lipid shell of MB (MB(RGD)). Six nude mice with tumor created by dorsal inoculation of HepG2 tumor cells were used as the test group.

[Effects of acute cerebral ischemia on cerebral perfusion: quantitative evaluation by contrast-enhanced ultrasound in dogs].

Objective: To evaluate the changes of cerebral blood flow (CBF) with real-time contrast-enhanced ultrasound (CEU) in a canine model of acute cerebral ischemia.

Methods: Cerebral perfusion was assessed in 6 dogs subjected to craniotomy with CEU at the time of 0, 30, 60, 90 and 120 min after occlusion of the left common carotid artery (LCCA). The microvascular volume (A) and blood flow velocity (beta) in the brain were measured from the time-versus-acoustic intensity plots, and the value of Axbeta were calculated.

[Effect of polyethylene oxide on red blood cell velocity in rat cremaster microcirculation].

Objective: To investigate the drag-reducing effect of polyethylene oxide (PEO) on the velocity of red blood cells in rat cremaster microcirculation.

Methods: Blood samples were collected from 6 Wistar male rats (100-110 g) via the post-orbital venous plexus. The red blood cells were separated by centrifugation and labeled by fluorescinisothiocyate (FITC).

[Molecular imaging of thrombus with microbubbles targeted to alphavbeta3-integrin using an agarose flow chamber model].

Objective: To assess the binding ability of microbubbles targeted to alphavbeta3-integrin (MBp) for thrombus-targeted contrast-enhanced ultrasound.

Methods: Targeted microbubbles were prepared by conjugating the monoclonal antibody against alphavbeta3-integrin to lipid shell of the microbubble via the avidin-biotin bridges. Equivalent isotype control microbubbles (MB) or targeted ultrasound microbubbles (MBp) were randomly added into the flow chamber.

[Evaluation of myocardial ischemia-reperfusion injury in mouse by molecular imaging of P-selectin with targeted contrast echocardiography].

Objective: To assess the feasibility of evaluating myocardial ischemia-reperfusion injury in mouse with targeted myocardial contrast echocardiography (MCE).

Methods: Phospholipid microbubbles targeted to P-selectin (MBp) and control microbubbles (MBc) were created by conjugating monoclonal antibody against murine P-selectin or isotype control antibody with the lipid shell via "avidin-biotin" bridging. Ten mice with myocardial ischemia-reperfusion were injected intravenously of MBp and MBc in a random order with a 30 min interval.

[Relationship between myocardial systolic, diastolic functions and perfusion in coronary artery stenosis].

Objective: To evaluate the relationship between myocardial systolic, diastolic functions and perfusion in coronary artery stenosis using velocity vector imaging (VVI) and myocardial contrast echocardiography (MCE).

Methods: Stenoses in the anterior descending branch of the coronary artery were induced in 8 dogs. Before and after coronary artery stenosis, two-dimensional images of the left ventricular mastoid muscle section on the short axis at rest and in the peak dose of dobutamine were obtained for evaluation of VVI and MCE.

[Effect of phospholipid- and albumin-coated microbubbles for myocardial opacification: a comparative study].

Objective: To evaluate the effect of a phospholipid-coated microbubble contrast agent for myocardium opacification in comparison with a albumin-coated microbubble contrast agent (Quanfuxian).

Methods: In 10 dogs with single coronary artery stenosis involving the anterior descending branch or circumflex branch randomly received infusion of the two contrast agents through the femoral vein. The myocardial blood flow, heart rate and blood pressure were analyzed qualitatively and quantitatively.

[Ultrasound-mediated microbubble destruction increases capillary permeability in rat skeletal muscles].

Objective: To investigate the effects of ultrasound mediated microbubble destruction on capillary permeability in rat skeletal muscles.

Methods: Eighteen SD rats were randomized into 3 groups, namely the Evans blue (EB) group, EB+ultrasound (E+U) group and EB+microbubble+ultrasound (U+E+M) group with corresponding treatments, using EB injected into the carotid artery as the indicator for capillary permeability. The microbubbles were injected through the carotid artery with fixed ultrasound parameters.

[Assessment of direct effects of dobutamine on coronary microcirculation with myocardial contrast echocardiography: comparison with adenosine].

Objective: To evaluate the direct effects of dobutamine as compared to adenosine on the coronary microcirculation in both normal and stenotic segments using myocardial contrast echocardiography (MCE).

Methods: Left anterior descending (LAD) coronary artery stenosis, which was not flow limiting at rest, was established in 9 dogs. At the baseline and during intracoronary infusion of dobutamine (2 mg.

[Nitroglycerine promotes myocardial oxygen metabolism and regional cardiac function in vivo].

Objective: To investigate the effects of nitroglycerine (NTG) on myocardial oxygen metabolism and regional cardiac function in canine hearts with a stable systemic hemodynamics in situ.

Methods: Eight anesthetized open-chest dogs with flow-limited left anterior descending branch of the coronary artery or left circumflex artery (LCx) stenosis were studied. The percentage of ventricular wall thickening (%WT) was measured with quantitative two-dimensional echocardiography (2DE), myocardial blood flow (MBF) with radiolabeled microspheres and tissue oxygen pressure (tPO(2).

Transmyocardial revascularization ameliorates ischemia by attenuating paradoxical catecholamine-induced vasoconstriction.

Background: The mechanism by which transmyocardial revascularization (TMR) offers clinical benefit is controversial. We hypothesized that TMR ameliorates ischemia by reversing paradoxical catecholamine-induced vasoconstriction.

Methods And Results: Chronic ischemic cardiomyopathy was created in 11 dogs by placing ameroid constrictors on the proximal coronary arteries and their major branches.

[Effect of microbubble cavitation on microcirculation of rat skeletal muscle].

Objective: To investigate the effect of therapeutic ultrasound-induced microbubble destruction on the microcirculation of rat skeletal muscle.

Methods: Thirty SD rats were randomized into 5 groups (n=6), namely normal saline, microbubble, ultrasound, high-energy ultrasound microbubble and low-energy ultrasound microbubble groups. Before and after the treatments, the diameter and blood flow velocity in the microvessels in the skeletal muscle were measured, and the structural changes of the injured microvessels observed by electron microscopy.

Effects of nitroglycerin on erythrocyte rheology and oxygen unloading: novel role of S-nitrosohemoglobin in relieving myocardial ischemia.

Background: We hypothesized that nitroglycerin improves O2 delivery to ischemic tissue by altering erythrocyte rheology and O2 unloading through an increase in bioactive nitric oxide (NO) content.

Methods And Results: Twelve dogs with resting flow-reducing single-vessel stenosis were studied at rest and during intracoronary infusion of nitroglycerin (0.3 to 0.

[Experimental study of the characteristics of renal blood flow with contrast ultrasound].

Objective: To study the characteristics of renal blood flow with contrast ultrasound.

Methods: The examination of the renal ultrasonography was performed in 10 dogs after intravenous injection of Quanfuxian (a contrast agent consisting of C3F8 microbubbles).

Results: Contrast visualization appeared in the renal cortex and then in the outer to inner medulla at the baseline level after administration of the contrast agent.

[An experimental study on renal microvascular perfusion in dogs with acute cardiac insufficiency].

Objective: To investigate the changes and the effects of captopril on the renal blood flow and microvascular perfusion in dogs with acute cardiac insufficiency.

Methods: Acute cardial insufficiency was induced by combining occlusion of the left anterior descending artery with right ventricular pacing in 12 mongrel dogs. The ascending aorta and left kidney were dissected and ultrasonic flow probes were placed on ascending aorta and renal artery to monitor cardiac output (CO) and renal blood flow (RBF).

[Quantification of renal medullary perfusion with contrast-enhanced ultrasound: an experimental study].

Objective: To quantitatively evaluate the effects of dopamine (DA) and noradrenaline (NE) on renal medullary perfusion and the differences in perfusion in the outer and inner medulla using contrast-enhanced ultrasound.

Methods And Results: Contrast-enhanced ultrasound was performed in 10 dogs with simultaneous renal artery flow (RAF) measurement at the baseline level and during application of 3 different doses of DA and NE. During treatment with the 3 doses of DA, the changes of ultrasound-derived parameters (A, beta and A*beta) in the medulla were similar to the changes in the cortex.

Effect of microbubble exposure to ultrasound on quantitation of myocardial perfusion.

Background: The purpose of this study was to determine whether acoustic disruption of microbubbles in the left ventricular (LV) cavity prior to entry in the coronary circulation or their gradual destruction in the myocardium during myocardial contrast echocardiography (MCE) affects quantitative parameters of myocardial perfusion.

Methods: MCE was performed in 12 open chest dogs with both intermittent high-power imaging (IHPI) and real-time low-power imaging (RLPI). To assess the affects of microbubble destruction in the LV cavity, MCE parameters of myocardial perfusion were compared for imaging planes that included versus avoided the LV cavity.

[Targeted adhesion of platelet receptor-specific microbubble agent to thrombus in vitro].

Objective: To examine the thrombus-targeting effect of platelet receptor-specific lipid microbubbles.

Methods: The targeted microbubbles were prepared by coupling Arg-Gly-Asp-Ser (RGDS) with the lipid microbubbles, which were added to the microthrombus generated by platelet aggregation. The effects of the targeted microbubbles on the ultrasonic signal was observed in an artificial thrombus model.

[Quantitative evaluation of canine renal blood flow with contrast-enhanced ultrasound].

Objective: To evaluate the accuracy of contrast-enhanced ultrasound (CEU) in renal blood flow quantification.

Methods: Regional renal perfusion was quantified with CEU in 10 dogs at the baseline level and after treatment with 3 doses of dopamine (3, 8 and 16 mg.kg(-1).

[Cardioprotective effects of K(ATP) channel opener nicorandil during ischemia/ reperfusion in dogs].

Objective: To further confirm the effect of nicorandil in reducing the area of myocardial infarct is through the mediation of activation of the KATP channel but not by its nitrate-like properties, and to determine whether the protective effect is the same or not when the drug is either given immediate after infarction or after reperfusion.

Methods: Thirty-five dogs were randomly divided into five groups as follows. Ischemia/reperfusion (IR) group: the dogs were subjected to 90 minutes of left anterior descending coronary artery(LAD) occlusion followed by 120 minutes reperfusion.