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1.
Clin Exp Pharmacol Physiol ; 50(8): 677-687, 2023 08.
Article in English | MEDLINE | ID: mdl-37203426

ABSTRACT

The diagnosis of heart failure with preserved ejection fraction (HFpEF) remains a challenge. There are three methods proposed as diagnostic tools. H2 FPEF score was determined by six weighted clinical characteristics and echocardiographic variables. Heart Failure Association (HFA)-PEFF algorithm consists of various functional and morphological variables as well as natriuretic peptides. SVI/S' is a novel echocardiographic parameter calculated by stroke volume index and mitral annulus systolic peak velocity. This study aimed to compare the three approaches in patients with suspected HFpEF. Patients referred to right heart catheterization for suspected HFpEF were classified into low-, intermediate- and high-likelihood groups according to H2 FPEF or HFA-PEFF scores. A diagnosis of HFpEF was confirmed by pulmonary capillary wedge pressure (PCWP) of ≥15 mm Hg according to the guidelines. In result, a total of 128 patients were included. Of these, 71 patients with PCWP ≥15 mm Hg and 57 patients with PCWP <15 mm Hg. Moderate correlations were observed between H2 FPEF score, HFA-PEFF score, SVI/S' and PCWP. The area under curve of SVI/S' was 0.82 for diagnosis of HFpEF, compared with 0.67 for H2 FPEF score and 0.75 for HFA-PEFF score by receiver-operating characteristics analysis. Combining SVI/S' with diagnostic scores showed higher Youden index and accuracy than each score alone. Kaplan-Meier analysis reported that the high-likelihood group showed poorer outcomes regardless the method used for diagnosis. Among the contemporary tools for identifying HFpEF in this study, the combination of SVI/S' with risk scores showed best diagnostic ability. Each of the strategies can determine rehospitalisation because of heart failure.


Subject(s)
Heart Failure , Humans , Stroke Volume , Heart Failure/diagnostic imaging , Echocardiography , Pulmonary Wedge Pressure , Risk Factors , Ventricular Function, Left
2.
ChemSusChem ; : e202400570, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38610068

ABSTRACT

Reasonable design of low-cost, high-efficiency and stable bifunctional oxygen electrocatalysts is of great significance to improve the reaction efficiency of Zn-air batteries, which is still a huge challenge. Here, we report a highly efficient bifunctional oxygen electrocatalyst with three-dimensional (3D) N-doped graphene network-supported cobalt and cobalt oxide nanoparticles (Co/CoO-NG), which can be in situ synthesized by inducing metal ions on metal plates via graphene oxide as an inducer. This 3D network structure and open active center show excellent bifunctional oxygen electrocatalytic activity under alkaline conditions, and can be used as an air electrode in rechargeable Zn-air batteries, with significantly better power density (244.28 mW cm-2) and stability (over 340 h) than commercial Pt/C+RuO2 mixtures. This work is conducive to advancing the practical application of graphene-based materials as air electrodes for rechargeable zinc-air batteries.

3.
Front Bioeng Biotechnol ; 11: 1276485, 2023.
Article in English | MEDLINE | ID: mdl-37929199

ABSTRACT

Acoustic manipulation techniques have gained significant attention across various fields, particularly in medical diagnosis and biochemical research, due to their biocompatibility and non-contact operation. In this article, we review the broad range of biomedical applications of micro/nano-motors that use acoustic manipulation methods, with a specific focus on cell manipulation, targeted drug release for cancer treatment and genetic disease diagnosis. These applications are facilitated by acoustic-propelled micro/nano-motors and nanoparticles which are manipulated by acoustic tweezers. Acoustic systems enable high precision positioning and can be effectively combined with magnetic manipulation techniques. Furthermore, acoustic propulsion facilitates faster transportation speeds, making it suitable for tasks in blood flow, allowing for precise positioning and in-body manipulation of cells, microprobes, and drugs. By summarizing and understanding these acoustic manipulation methods, this review aims to provide a summary and discussion of the acoustic manipulation methods for biomedical research, diagnostic, and therapeutic applications.

4.
Ultrason Sonochem ; 101: 106724, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38100894

ABSTRACT

The dual-transducer support structure discussed has the advantages of a simple structure and low cost, as well as allowing for the use of both Traveling-Wave (TW) and Standing-Wave (SW) acoustic transportation, supporting its use in pharmaceutical and biochemical analysis, for example. By adjusting the distance between the vibrating plate and the reflector which forms SW field in the y direction, the control of the position of the SW nodes or the TW component along the x direction allows the formation of a Two-Dimensional Standing Wave (2D-SW) or a Traveling Wave (TW) acoustic field, and these could be used for transportation in the x direction. It has been found that the x position of the SW nodes can be adjusted through changing the temporal phase shift, θ, which permits multiple objects to be transported using the 2D-SW mode. By comparison, TWs in the opposite direction could be generated at a pair of specific temporal phase shifts, allowing fast transportation using the TW mode. In this research work, an experiment has been carried out to transport polystyrene spheres using the two modes by programming the temporal phase shift, θ, this illustrating that precise position control of the multiple objects transported was possible using the 2D-SW mode, while high-speed transportation (up to 540 mm/s) was realized using the TW mode, showing that the dual-transducer support structure could be used effectively for accurate and fast transportation. As a fully non-contact method, the dual-transducer support structure can be seen to work in the 2D-SW mode for reaction synthesis or detection applications, and also in TW mode for rapid sample transportation applications.

5.
Clin Case Rep ; 10(7): e6105, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35865766

ABSTRACT

Acute pulmonary embolism (APE) is a life-threatening disease with nonspecific clinical signs and symptoms. Rapid and accurate diagnosis is crucial for the clinical management of patients with acute pulmonary embolism. A recommended echocardiography view may be of further help in the diagnosis and evaluation of the change in thrombosis and treatment. We reported a case of a 74-year-old man with a 12-day history of decreased exercise capacity and dyspnea. The patient was diagnosed with intermediate-risk APE as several pulmonary emboli in pulmonary artery were seen in multidetector computed tomographic pulmonary angiography with normal blood pressure and echocardiographic right ventricular overload. And we found a pulmonary artery clot in the right pulmonary artery through transthoracic echocardiography. After 11-days anticoagulation, the patient underwent a reassessment, showed a decrease in RV diameter and pulmonary artery thrombus. This case highlights the significant role that echocardiography played in a patient who presented pulmonary embolism with a stable hemodynamic situation and normal blood pressure. The modified echocardiographic view could provide correct diagnosis by identifying the clot size and location visually. Knowledge of the echocardiography results of APE would aid the diagnosis.

6.
Front Cardiovasc Med ; 9: 1087287, 2022.
Article in English | MEDLINE | ID: mdl-36620612

ABSTRACT

Background: Early detection of subclinical cardiotoxicity of immune checkpoint inhibitor (ICI) therapy can be challenging. Objective: To evaluate subclinical cardiac dysfunction using two-dimensional speckle tracking imaging (2D-STI) and three-dimensional echocardiography in Chinese patients. Methods: Fifty-five consecutive patients with malignant tumors treated by immunotherapy were included. They were examined by echocardiography before immunotherapy and after immunotherapy. Left ventricular ejection fraction (LVEF) was calculated in three-dimensional imaging. Moreover, left ventricular global longitudinal peak systolic strain (LVGLS), left ventricular global circumferential peak systolic strain (LVGCS), right ventricular global longitudinal systolic strain (RVGLS), right ventricular free wall longitudinal peak systolic strain (RVFWLS), and tricuspid annular plane systolic excursion (TAPSE) were evaluated. Clinical and laboratory parameters were recorded. Cardiac toxicity events were defined as the presence of heart failure symptoms, LVEF reduction, and increase in troponin. Subclinical cardiac toxicity was defined as cardiac dysfunction associated with ICI treatment, with absent or delayed ICI-associated cardiotoxicity clinical symptoms. Results: Compared with baseline, the LVGLS, TAPSE, and RVGLS significantly deteriorated after ICI treatment [(-18.63 ± 2.53)% vs. (-17.35 ± 2.58)%, P = 0.000; 18.29 ± 6.23 vs. 14.57 ± 3.81, P = 0.0001; and (-18.45 ± 4.65)% vs. (-14.98 ± 3.85)%, P = 0.0001, respectively]. LVGLS (-17.35 ± 2.58, P = 0.000), TAPSE (14.57 ± 3.81, P = 0.0001), and RVGLS [(-14.98 ± 3.85)%, P = 0.0001] were decreased after ICI immunotherapy. Kaplan-Meier curve analysis showed that LVGLS was more sensitive than the cardiac toxicity events to assess ICI-related subclinical cardiac dysfunction (log-rank P = 0.205). The ROC curve showed that the cutoff value of ΔLVGLS was -13%. Conclusion: Subclinical cardiac dysfunction can be detected using two-dimensional speckle-tracking imaging. LVGLS, RVGLS, and TAPSE are more sensitive indices for detection. Clinical trial registration: [https://www.chictr.org.cn/showprojen.aspx?proj=27498], identifier [ChiCTR1800016216].

7.
Lab Chip ; 22(18): 3402-3411, 2022 09 13.
Article in English | MEDLINE | ID: mdl-35899764

ABSTRACT

Droplet actuation using Surface Acoustic Wave (SAW) technology has been widely employed in 'lab-on-a-chip' applications, such as for on-chip Polymerase Chain Reactions. The current strategy uses the exciter-absorber mode (exciting a single InterDigital Transducer, IDT) to form a pure Travelling Surface Acoustic Wave (TSAW) and to actuate the droplet, where the velocity and direction of the droplet can be adjusted by controlling the on-off and amplitude of the excitation signals applied to a pair of IDTs. Herein, in a way that is different from using the exciter-absorber mode, we propose a method of actuating droplets by using the exciter-exciter mode (exciting a pair of IDTs simultaneously), where the velocity and directional adjustment of the droplet can be realized by changing only one excitation parameter for the signals (the temporal phase shift, θ), and the droplet velocity can also be significantly improved. Specifically, we report for the first time the equation of the vibration of the mixed waves (TSAW and Standing Surface Acoustic Wave (SSAW)) formed on the substrate surface using the exciter-exciter mode. This is analyzed theoretically, where it is shown in this work that the amplitude and direction of the TSAW component of the mixed waves can be adjusted by changing θ. Following that, the velocity and directional adjustment of the droplet has been realized by changing θ and the improvement of the droplet velocity has been verified on a one-dimensional SAW device, using this exciter-exciter mode. Moreover a series of experiments on droplet transportation, along different trajectories in an x-y plane, has been carried out using a two-dimensional SAW device and this has demonstrated the effectiveness of the θ changing-based approach. Here this exciter-exciter mode provides an alternative method for the transportation of droplets in 'lab-on-a-chip' applications.


Subject(s)
Sound , Transducers , Vibration
8.
Front Cardiovasc Med ; 9: 822314, 2022.
Article in English | MEDLINE | ID: mdl-35224053

ABSTRACT

INTRODUCTION: The diagnosis of heart failure with preserved ejection fraction (HFpEF) remains challenging. In this study, a novel echocardiography index based on three-dimensional and tissue Doppler echocardiography for diagnosing and estimating prognosis in HFpEF. MATERIALS AND METHODS: Patients with symptoms and/or signs of heart failure and normal left ventricular ejection fraction (LVEF ≥50%) who underwent right heart catheterization were screened. Patients were divided based on pulmonary capillary wedge pressure (PCWP) of ≥15 mmHg and PCWP <15 mmHg. A diagnosis of HFpEF was confirmed by PCWP of ≥15 mmHg according to ESC guidelines. A novel index was calculated by the ratio between stroke volume standardized to body surface area (SVI) and tissue Doppler mitral annulus systolic peak velocity S' (SVI/S'). Its diagnostic and prognostic values were determined. RESULTS: A total of 104 patients (mean age 64 ± 12 years) were included. Of these, 63 had PCWP ≥15 mmHg and 41 patients had PCWP <15 mmHg. Compared to the PCWP <15 mmHg group, the ≥15 mmHg group had a significantly lower SVI/S' (P < 0.001). Logistic regression showed that SVI/S' was associated with high PCWP measured invasively. The SVI/S' had an area under the curve of 0.761 for diagnosing classifying between PCWP ≥15 mmHg and <15 mmHg. Kaplan-Meier analysis showed that the lower SVI/S' group showed a poorer prognosis. CONCLUSIONS: SVI/S' is a non-invasive index calculated by three-dimensional and tissue Doppler echocardiography. It is a surrogate measure of PCWP and can be used to diagnose and determine prognosis in HFpEF.

9.
Front Physiol ; 11: 580624, 2020.
Article in English | MEDLINE | ID: mdl-33364973

ABSTRACT

Background: The possible association between atrial fibrillation (AF) and left ventricular-to-right atrial shunt (LVRAS) has never been reported yet. The present study investigated the incidence of AF in LVRAS. Methods: This was a retrospective study of consecutive patients undergoing echocardiography at a single tertiary center. Clinical data, laboratory results and echocardiography parameters such as right atrial area (RAA), right ventricular end diastolic diameter (RVDD) and left atrial diameter (LAD) were compared between LVRAS group and non-LVRAS patients, and between AF and non-AF patients. Propensity score matching was performed to decrease the effect of confounders. Logistic regression analysis and mediation analysis were used to estimate the relationship between LVRAS and AF. Results: A total of 3,436 patients were included, and the incidence of LVRAS was 1.16% (n = 40). The LVRAS group had significantly larger RAA, RVDD and LAD compared with non-LVRAS group. Those who suffered from AF showed larger RAA, RVDD and LAD compared with those who maintained sinus rhythm. Multivariable logistic regression showed that gender (OR: 0.608), age (OR: 1.048), LAD (OR: 1.111), mean pulmonary artery blood pressure (mPAP, OR: 1.023), TR (OR: 2.309) and LVRAS (OR: 12.217) were significant factors for AF. RAA could partially mediate the relationship between LVRAS and AF according to the result of mediation analysis. Conclusions: Our study suggested that LVRAS, TR, LAD, mPAP, age and male were risk factors for AF. RA enlargement might underlie mechanism in the higher incidence of AF in LVRAS patients. These findings should be confirmed in larger prospective studies.

10.
Micromachines (Basel) ; 9(11)2018 Oct 23.
Article in English | MEDLINE | ID: mdl-30715039

ABSTRACT

Recent strides in micro- and nanomanufacturing technologies have sparked the development of micro-/nanorobots with enhanced power and functionality. Due to the advantages of on-demand motion control, long lifetime, and great biocompatibility, magnetic propelled micro-/nanorobots have exhibited considerable promise in the fields of drug delivery, biosensing, bioimaging, and environmental remediation. The magnetic fields which provide energy for propulsion can be categorized into rotating and oscillating magnetic fields. In this review, recent developments in oscillating magnetic propelled micro-/nanorobot fabrication techniques (such as electrodeposition, self-assembly, electron beam evaporation, and three-dimensional (3D) direct laser writing) are summarized. The motion mechanism of oscillating magnetic propelled micro-/nanorobots are also discussed, including wagging propulsion, surface walker propulsion, and scallop propulsion. With continuous innovation, micro-/nanorobots can become a promising candidate for future applications in the biomedical field. As a step toward designing and building such micro-/nanorobots, several types of common fabrication techniques are briefly introduced. Then, we focus on three propulsion mechanisms of micro-/nanorobots in oscillation magnetic fields: (1) wagging propulsion; (2) surface walker; and (3) scallop propulsion. Finally, a summary table is provided to compare the abilities of different micro-/nanorobots driven by oscillating magnetic fields.

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