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1.
Small ; 20(33): e2400906, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38593313

RESUMO

Marangoni actuators that are propelled by surface tension gradients hold significant potential in small-scale swimming robots. Nevertheless, the release of "fuel" for conventional chemical Marangoni actuators is not easily controllable, and the single swimming function also limits application areas. Constructing controllable Marangoni robots with multifunctions is still a huge challenge. Herein, inspired by water striders, electricity-driven strategies are proposed for a multifunctional swimming Marangoni robot (MSMR), which is fabricated by super-aligned carbon nanotube (SACNT) and polyimide (PI) composite. The MSMR consists of a Marangoni actuator and air-ambient actuators. Owing to the temperature gradient generated by the electrical stimulation on the water surface, the Marangoni actuators can swim controllably with linear, turning, and rotary motions, mimicking the walking motion of water striders. In addition, the Marangoni actuators can also be driven by light. Importantly, the air-ambient actuators fabricated by SACNT/PI bilayer structures demonstrate the function of grasping objects on the water surface when electrically Joule-heated, mimicking the predation behavior of water striders. With the synergistic effect of the Marangoni actuator and air-ambient actuators, the MSMR can navigate mazes with tunnels and grasp objects. This research will provide a new inspiration for smart actuators and swimming robots.

2.
BMC Pediatr ; 24(1): 552, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39192246

RESUMO

BACKGROUND: Coarctation of the aorta (CoA) is the most common undiagnosed congenital heart defect during prenatal screening. High false positive and false negative rates seriously affect prenatal consultation and postnatal management. The objective of the study was to assess the utility of various measurements to predict prenatal CoA and to derive a diagnostic algorithm. METHODS: One hundred and fifty-four fetuses with suspected CoA who presented at Fuwai Hospital between December 2017 and August 2021 were enrolled and divided into confirmed CoA cases (n = 47) and false positive cases (n = 107), according to their postnatal outcomes. The transverse aortic arch, isthmus, and descending aorta were measured in the long-axis view of the aortic arch. The angle between the transverse aortic arch (TAO) and the descending aortic arch (DAO) was defined as the TAO-DAO angle and measured in the long axis or sagittal view. Based on the database in GE Voluson E10 and the formula (Z = [Formula: see text]), the standard score (Z-score) of the dimensions of the aorta were calculated in relation to the gestational age. The main echocardiographic indices were combined to design a 3-step diagnostic protocol. The TAO-DAO angle was used as the first step in the diagnostic model. The diameter of the transverse arch and the Z-score of the isthmus were the second step. The third-step indices included a Z-score of the transverse arch, diameter of the isthmus, distance from the left subclavian artery (LSA) to left common carotid artery (LCCA), the ratio of isthmus diameter and LSA diameter and ratio of the distances (the distance between the LSA and LCCA to the distance between the right innominate artery and LCCA). The receiver operating characteristic (ROC) curve determined the predictive capability of each diagnostic parameter, and the kappa test determined the diagnostic accuracy of the proposed model. RESULTS: The cases with confirmed CoA had thinner transverse arches (1.92 ± 0.32 mm vs. 3.06 ± 0.67 mm, P = 0.0001), lower Z-scores of the isthmus (-8.97 ± 1.45 vs. -5.65 ± 1.60, P = 0.0001), smaller TAO-DAO angles (105.54 ± 11.51° vs. 125.29 ± 8.97°, P = 0.0001) and larger distance between the LSA and LCCA (4.45 ± 1.75 mm vs. 2.74 ± 1.07 mm, P = 0.0001) than the false positive cases. The area under the curve (AUC) was 0.947 (95% CI 0.91-0.98) for the TAO-DAO angle ≤ 115.75°, 0.942 (95% CI 0.91-0.98) for the transverse arch diameter ≤ 2.31 mm, 0.937 (95% CI 0.90-0.98) for the Z-score of the isthmus ≤ -7.5, and 0.975 (95% CI 0.95-1.00) for the 3-step diagnostic protocol with 97.8% sensitivity and 97.2% specificity. The kappa test showed that the model's diagnostic accuracy was consistent with postnatal outcomes (kappa value 0.936, P = 0.0001). CONCLUSIONS: The 3-step diagnostic protocol included the three most useful measurements and the additional indices with appropriate cut-off values. The algorithm is useful for the detection of aortic coarctation in fetuses with a high degree of accuracy. TRIAL REGISTRATION: Retrospectively registered.


Assuntos
Aorta Torácica , Coartação Aórtica , Ecocardiografia , Ultrassonografia Pré-Natal , Humanos , Coartação Aórtica/diagnóstico por imagem , Feminino , Gravidez , Aorta Torácica/diagnóstico por imagem , Estudos Retrospectivos , Algoritmos , Idade Gestacional
3.
Int Heart J ; 65(4): 723-729, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39085111

RESUMO

Congenital heart disease (CHD) accounts for nearly one-third of all major congenital anomalies, with atrial septal defect (ASD) and ventricular septal defect (VSD) being the most common forms of simple CHD, which involve a large number of susceptibility genes. However, despite extensive research, the etiology of ASD and VSD remains unclear. Yunnan Province has advantages in exploring CHD pathogenesis due to its unique genetic background. Therefore, we aimed to evaluate the association between single nucleotide polymorphisms (SNPs) of genes and susceptibility to simple CHD in a specific population by means of a case-control study. A total of 337 healthy controls and 767 patients with simple CHD (501 ASD and 266 VSD) from China were recruited. Candidate SNPs were identified through whole-genome sequencing of pooled CHD patients and controls (pool-seq). Genotyping from 1,104 samples was performed, and stratified analysis was conducted to explore the association between positive SNPs and CHD subtypes. χ2 tests and logistic regression were used to analyze the relationship between each SNP and simple CHD. Of 11 SNPs identified, SOD2 rs62437333 (P = 0.005) and POU5F1 rs3130504 (P = 0.017) showed differences between the control and ASD cohorts. In the dominant inheritance model hypothesis, rs62437333 allele C carriers had increased ASD (odds ratio (OR) = 2.04, P = 0.005) and combined simple CHD risk (OR = 2.33, P = 0.012) compared to DD genotype, while rs3130504 allele C carriers had increased ASD risk (OR = 1.121, P = 0.045) compared to DD genotype.


Assuntos
Povo Asiático , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Superóxido Dismutase , Humanos , Masculino , Feminino , China/epidemiologia , Estudos de Casos e Controles , Superóxido Dismutase/genética , Povo Asiático/genética , Cardiopatias Congênitas/genética , Criança , Adulto , Pré-Escolar , Adolescente , Comunicação Interatrial/genética , Comunicação Interventricular/genética , Comunicação Interventricular/epidemiologia , Genótipo , População do Leste Asiático
4.
Small ; : e2309498, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38084445

RESUMO

Most exogenous electronic skins (e-skins) currently face challenges of complex structure and poor compatibility with the human body. Utilizing human secretions (e.g., sweat) to develop e-skins is an effective solution strategy. Here, a new kind of "sweat-driven" e-skin is proposed, which realizes energy-storage and thermal-management multifunctions. Through the layer-by-layer assembly of MXene-carbon nanotube (CNT) composite with paper, lightweight and versatile e-skins based on supercapacitors and actuators are fabricated. Long CNTs wrap and entangle MXene nanosheets, enhancing their long-distance conductivity. Furthermore, the CNT network overcomes the structural collapse of MXene in sweat, improving the energy-storage performance of e-skin. The "sweat-driven" all-in-one supercapacitor with a trilayer structure is patternable, which absorbs sweat as electrolyte and harnesses the ions therein to store energy, exhibiting an areal capacitance of 282.3 mF cm-2 and a high power density (2117.8 µW cm-2 ). The "sweat-driven" actuator with a bilayer structure can be driven by moisture (bending curvature of 0.9 cm-1 ) and sweat for personal thermal management. Therefore, the paper serves as a separator, actuating layer, patternable layer, sweat extractor, and reservoir. The "sweat-driven" MXene-CNT composite provides a platform for versatile e-skins, which achieve the interaction with humans and offer insights into the development of multifunctional wearable electronics.

5.
Opt Express ; 31(12): 19958-19967, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381400

RESUMO

Micro bunched electron beams with periodic longitudinal density modulation at optical wavelengths give rise to coherent light emission. In this paper, we show attosecond micro bunched beam generation and acceleration in laser-plasma wakefield via particle-in-cell simulations. Due to the near-threshold ionization with the drive laser, the electrons with phase-dependent distributions are non-linearly mapped to discrete final phase spaces. Electrons can preserve this initial bunching structure during the acceleration, leading to an attosecond electron bunch train after leaving the plasma with separations of the same time scale. The modulation of the comb-like current density profile is about 2k0 ∼ 3k0, where k0 is the wavenumber of the laser pulse. Such pre-bunched electrons with low relative energy spread may have potential in applications related to future coherent light sources driven by laser-plasma accelerators and broad application prospects in attosecond science and ultrafast dynamical detection.

6.
J Card Surg ; 37(5): 1242-1249, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35220611

RESUMO

BACKGROUND: Severe mitral regurgitation (MR) is associated with progressive heart failure and impairment of survival. Degenerative MR accounts for most MV repair surgeries. Conventional mitral valve repair surgery requires cardiopulmonary bypass and is associated with significant morbidity and risks. Transapical beating-heart mitral valve repair by artificial chordae implantation with transesophageal echocardiography (TEE) guidance has the potential to significantly reduce surgical morbidity. We report the first-in-human experience of degenerative MR repair using a novel artificial chordae implantation device (MitralstitchTM system). METHODS: Ten patients with severe MR underwent transapical artificial chordae implantation using MitralstitchTM system. The procedure was performed through a small left thoracotomy under general anesthesia and TEE guidance. Patients underwent transthoracic echocardiography and other assessments during the follow-up. RESULTS: All 10 patients with an average age of 63.7 ± 9.6 years successfully received transapical artificial chordae implantation. Their MR reduced from severe to none or trace in five patients, mild in five patients before discharge. Five patients received one artificial chordal implantation, four patients received two, and one patient received three and edge-to-edge repair by locking two of them. The safety and efficacy endpoint were achieved in all patients at 1-month follow-up. At 1-year follow-up, six patients had mild MR, three patients had moderate MR, one patient had recurrence of severe MR and underwent surgical repair. CONCLUSIONS: The results of this first-in-human study show safety and feasibility of transapical mitral valve repair using MitralStitch system. Patient selection and technical refinement are crucial to improve the outcomes.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Prolapso da Valva Mitral , Idoso , Cordas Tendinosas/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Prolapso da Valva Mitral/cirurgia , Resultado do Tratamento
7.
Langmuir ; 37(8): 2629-2638, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33586440

RESUMO

Enhanced vapor condensation is a critical issue for improving the efficiency of energy conversion, thermal management, water recovery, and treatment. Low-energy surfaces incorporating micro/nanoscale roughness have been reported to significantly promote vapor condensation. In this research, the mesh structures of super-aligned carbon nanotube (SACNT) films were prepared by crossing monolayer SACNT films on a copper substrate. Then, the sustaining dropwise condensation was achieved on the SACNT mesh-coated surface. The SACNT mesh-coated surface could obviously enhance the coalescence and sweeping departure of the condensing droplets. Additionally, the measured overall heat transfer coefficient (HTC) of the SACNT mesh-coated surface demonstrated a 36% enhancement compared to that on the bare copper surface. The parallel stacking of SACNT films with different groove structures was also studied, and a 15% enhancement in the HTC was shown as compared with the bare copper surface. Furthermore, we developed a morphology-based model to theoretically analyze the condensation-enhancement mechanism on a SACNT mesh-coated surface. The SACNT surfaces also have advantages of low cost, durability, flexibility, and extensibility. Our findings revealed that the SACNT films could be readily used as vapor condensation-strengthening surfaces, further extending their potential applications to industrial equipment.

8.
Neurobiol Dis ; 140: 104851, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32243914

RESUMO

BACKGROUND: Variations in TOR1A were thought to be associated with early-onset isolated dystonia. The variant S287Y (NM_000113.2: c.860C > A, p. Ser287Tyr, rs766483672) was found in our late-onset isolated dystonia patient. This missense variant is adjacent to R288Q (c.863G > A, p. Arg288Gln), which was reported to be associated with isolated dystonia. The potentially pathogenic role of S287Y is not conclusively known. METHODS: Cytological and molecular biological analyses were performed in vitro to determine whether this variant damages the structure and function of the cell. RESULTS: Compared with the SH-SY5Y cells overexpressing wild-type TOR1A, the cells overexpressing the protein with S287Y have an enlarged peri-nuclear space. The same changes in nuclear morphology were also found in the cells overexpressing the pathogenic variants ΔE (NM_000113.2:c.904_906delGAG, p. Glu302del), F205I (NM_000113.2:c.613 T > A, p. Phe205Ile), and R288Q (NM_000113.2:c.863G > A, p. Arg288Gln). Mutated proteins with S287Y presented a higher tendency to form dimers under reducing conditions. The same tendencies were observed in other mutated proteins but not in wild-type torsinA. CONCLUSIONS: TorsinA with S287Y damages the structure of the cell nucleus and may be a novel pathogenic mutation that causes isolated dystonia.


Assuntos
Distonia/genética , Distúrbios Distônicos/genética , Mutação , Humanos , Masculino , Pessoa de Meia-Idade , Chaperonas Moleculares
9.
Clin Sci (Lond) ; 134(3): 349-358, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31971563

RESUMO

BACKGROUND/AIMS: Congenital heart disease (CHD) is one of the most common and severe congenital defects. The incidence of fetal cardiac malformation is increased in the context of maternal gestational diabetes mellitus (GDM). Therefore, we wanted to determine whether abnormalities in the insulin signaling pathway are associated with the occurrence of nonsyndromic CHD (ns-CHD). METHODS: We used digital gene expression profiling (DGE) of right atrial myocardial tissue samples from eight ns-CHD patients and four controls. The genes potentially associated with CHD were validated by real-time fluorescence quantitative PCR analysis of right atrial myocardial tissues from 37 patients and 10 controls and the H9C2 cell line. RESULTS: The results showed that the insulin signaling pathway, which is mediated by the SHC gene family, was inhibited in the ns-CHD patients. The expression levels of five genes (PTPRF, SHC4, MAP2K2, MKNK2, and ELK1) in the pathway were significantly down-regulated in the patients' atrial tissues (P<0.05 for all). In vitro, the H9C2 cells cultured in high glucose (33 mmol/l) expressed less SHC4, MAP2K2, and Elk-1 than those cultured in low glucose (25 mmol/l). Furthermore, the high glucose concentration down-regulated the 25 genes associated with blood vessel development based on Gene Ontology (GO) term enrichment analyses of RNA-seq data. CONCLUSION: We considered that changes in the insulin signaling pathway mediated by SHC might be involved in the heart development process. This mechanism might account for the increase in the incidence of fetal cardiac malformations in the context of GDM.


Assuntos
Povo Asiático , Regulação para Baixo , Cardiopatias Congênitas/metabolismo , Insulina/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Transdução de Sinais , Animais , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Ontologia Genética , Cardiopatias Congênitas/genética , Humanos , Ratos , Reprodutibilidade dos Testes
10.
Med Sci Monit ; 22: 2846-51, 2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27518153

RESUMO

BACKGROUND The aim of this study was to evaluate the value of the implantable loop recorder (ILR) in diagnosing atrial fibrillation (AF) and assessing the postoperative efficacy of radiofrequency catheter ablation (RFCA). MATERIAL AND METHODS A total of 32 patients who successfully underwent RFCA were selected. These patients discontinued antiarrhythmic medication with no AF recurrence for more than 3 months after RFCA, and underwent ILR placement by a conventional method. The clinical manifestations and information on arrhythmias recorded by the ILR were followed up to assess the efficacy of AF RFCA. RESULTS The mean follow-up period was 24.7±12.5 months. Of 32 patients with ILR information, 27 had successful RFCA and 5 had recurrent AF. The follow-up results obtained by traditional methods showed 29 patients with successful RFCA and 3 with recurrent AF (P<0.05). Among the 18 patients with clinical symptoms, 13 had recorded cardiac arrhythmic events (72.2%) and 5 showed sinus rhythm (27.8%). The ILRs recorded 18 patients with arrhythmic events (56.3%), including 12 cases of atrial arrhythmias, among whom 5 recurred at 9, 12, 16, 17, and 32 months after AF RFCA; there were also 2 patients with ventricular tachycardia (VT) and 4 with bradycardia. CONCLUSIONS The value of ILR in assessing the efficacy of AF RFCA was superior to that of traditional methods. ILR can promptly detect asymptomatic AF, and can monitor electrocardiogram features after RFCA, thus providing objective evidence of efficacy.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/instrumentação , Eletrocardiografia Ambulatorial/instrumentação , Adulto , Idoso , Antiarrítmicos/administração & dosagem , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Eletrocardiografia , Eletrocardiografia Ambulatorial/métodos , Feminino , Humanos , Neuroestimuladores Implantáveis , Masculino , Pessoa de Meia-Idade , Autoeficácia
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