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1.
Sci Rep ; 14(1): 6306, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491090

RESUMO

Early identification of women at high risk for cardiovascular diseases (CVD), with subsequent monitoring, will allow for improved clinical outcomes and generally better quality of life. This study aimed to identify the associations between early menopause, abnormal diastolic function, and clinical outcomes. This retrospective study included 795 menopausal women from is a nationwide, multicenter, registry of patients with suspected angina visiting outpatient clinic. The patients into two groups: early and normal menopause (menopausal age ≤ 45 and > 45 years, respectively). If participants met > 50% of the diastolic function criteria, they were classified as having normal diastolic function. Multivariable-adjusted Cox models were used to test associations between menopausal age and clinical outcomes including the incidence of major adverse cardiovascular events (MACE), over a median follow-up period of 771 days. Early menopause was associated with increased waist circumference (p = 0.001), diabetes prevalence (p = 0.003), obstructive coronary artery disease (p = 0.005), abnormal diastolic function (p = 0.003) and greater incidences of MACE, acute coronary syndrome, and hospitalization for heart failure. In patients with abnormal diastolic function, early menopause increased MACE risk significantly, with no significant difference in normal diastolic function. These findings highlight early menopause and abnormal diastolic function as being potential risk markers in women for midlife CVD events.


Assuntos
Síndrome Coronariana Aguda , Doenças Cardiovasculares , Feminino , Humanos , Pessoa de Meia-Idade , Angina Pectoris/epidemiologia , Doenças Cardiovasculares/epidemiologia , Menopausa , Qualidade de Vida , Estudos Retrospectivos , Fatores de Risco
2.
Clin Res Cardiol ; 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112743

RESUMO

AIMS: This study evaluated the sex differences of sequential changes in coronary blood flows and microvascular function in patients with suspected angina but with no obstructed coronary arteries. METHODS: A total of 202 consecutive patients who experienced chest pain but had no significant coronary artery stenosis and who underwent adenosine stress echocardiography were included in the study. Coronary blood flow (CBF) velocities were measured at 1, 2, and 3 min after adenosine infusion. RESULTS: The mean age was 61 years, and 138 (68%) were women. Approximately 40% of patients had coronary microvascular dysfunction (CMD, coronary flow velocity reserve < 2.3), with women exhibiting higher CMD prevalence. The left ventricular (LV) mass index was similar between men and women, while women exhibited higher baseline rate pressure products (RPP). At baseline, coronary blood flow velocities were similar between the sexes. However, CBF velocities in women gradually increased during the examination; and in men, the increase was abrupt and steep during the early stages of examination (p = 0.015 for interaction between time and sex), even with similar RPP in stress. Coronary flow velocity reserve was steadily lower in women compared to men (1 min, 2.09 ± 0.86 vs 2.44 ± 0.87; 2 min, 2.39 ± 0.72 vs 2.63 ± 0.85; 3 min, 2.45 ± 0.70 vs 2.68 ± 0.73). CONCLUSIONS: In patients with suspected angina but with no obstructed coronary arteries, CMD was especially prevalent among women. Women exhibited higher oxygen consumption, while exhibiting slower and gradual increases in CBF velocities. Conversely, men exhibited faster and steeper increases in CBF velocities even with similar RPP in stress.

3.
Nanoscale ; 15(33): 13675-13684, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37554054

RESUMO

Most commercial drones utilize a traditional proportional-integral-derivative (PID) controller because of its design simplicity. However, the traditional PID controller has certain limitations in terms of optimality and robustness; it is difficult to actively adjust the PID gains under some disturbances. In this study, we demonstrated an analog-digital hybrid computing platform based on double-gate SnS2 memtransistors to implement a self-tuning/energy-efficient PID controller in drones. The customized analog circuit with memtransistors executes the PID control algorithm with low power consumption; we experimentally verified that the energy consumption of the proposed hybrid computing-based PID controller is only 63% of that of the traditional PID controller. In addition, the precise tunability of analog conductance states in the memtransistor proved to be capable of reconfiguring the performance of the PID controller, where the developed self-tuning algorithm can automatically find the optimal PID control performance.

4.
Nanomaterials (Basel) ; 13(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37368278

RESUMO

In aerospace applications, SiOx deposition on perovskite solar cells makes them more stable. However, the reflectance of the light changes and the current density decreases can lower the efficiency of the solar cell. The thickness of the perovskite material, ETL, and HTL must be re-optimized, and testing the number of cases experimentally takes a long time and costs a lot of money. In this paper, an OPAL2 simulation was used to find the thickness and material of ETL and HTL that reduces the amount of light reflected by the perovskite material in a perovskite solar cell with a silicon oxide film. In our simulations, we used an air/SiO2/AZO/transport layer/perovskite structure to find the ratio of incident light to the current density generated by the perovskite material and the thickness of the transport layer to maximize the current density. The results showed that when 7 nm of ZnS material was used for CH3NH3PbI3-nanocrystalline perovskite material, a high ratio of 95.3% was achieved. In the case of CsFAPbIBr with a band gap of 1.70 eV, a high ratio of 94.89% was shown when ZnS was used.

5.
ACS Sens ; 8(5): 2105-2114, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37161287

RESUMO

Memristor-based gas sensors (gasistors) have been considered as the most promising candidate for detecting NO gas suitable for neural network (NN) analysis. In this work, in order to solve an overfitting issue arising from the training data when using a single gasistor, which degrades the accuracy of NN, we here propose a metal-insulator-silicon (MIS)-structured Zr3N4-based gasistor array that results in an improvement in both the accuracy of the NN analysis and the efficiency of the operating power. As a result, the proposed gasistor array showed a decrease of epoch and a 2.5% improvement of prediction accuracy at room temperature compared to single cells with metal/insulator/metal (MIM) and MIS structures. These results imply that an array structure based on MIS can efficiently solve the overfitting issue by receiving multiple responses at once, compared to a single gas sensor that obtains one response per sensing.


Assuntos
Metais , Silício , Silício/química , Redes Neurais de Computação
6.
Nanomaterials (Basel) ; 13(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37177095

RESUMO

Antireflection coatings (ARCs) with an indium thin oxide (ITO) layer on silicon heterojunction solar cells (SHJ) have garnered significant attention, which is due to their potential for increasing current density (Jsc) and enhancing reliability. We propose an additional tungsten trioxide (WO3) layer on the ITO/Si structure in this paper in order to raise the Jsc and demonstrate the influence on the SHJ solar cell. First, we simulate the Jsc characteristics for the proposed WO3/ITO/Si structure in order to analyze Jsc depending on the thickness of WO3 using an OPAL 2 simulator. As a result, the OPAL 2 simulation shows an increase in Jsc of 0.65 mA/cm2 after the 19 nm WO3 deposition on ITO with a doping concentration of 6.1 × 1020/cm2. We then fabricate the proposed samples and observe an improved efficiency of 0.5% with an increased Jsc of 0.75 mA/cm2 when using a 20 nm thick WO3 layer on the SHJ solar cell. The results indicate that the WO3 layer can be a candidate to improve the efficiency of SHJ solar cells with a low fabrication cost.

7.
Nanomaterials (Basel) ; 13(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37242080

RESUMO

BN-based resistive random-access memory (RRAM) has emerged as a potential candidate for non-volatile memory (NVM) in aerospace applications, offering high thermal conductivity, excellent mechanical, and chemical stability, low power consumption, high density, and reliability. However, the presence of defects and trap states in BN-based RRAM can limit its performance and reliability in aerospace applications. As a result, higher set voltages of 1.4 and 1.23 V were obtained for non-annealed and nitrogen-annealed BN-based RRAM, respectively, but lower set voltages of 1.06 V were obtained for hydrogen-annealed BN-based RRAM. In addition, the hydrogen-annealed BN-based RRAM showed an on/off ratio of 100, which is 10 times higher than the non-annealed BN-based RRAM. We observed that the LRS changed to the HRS state before 10,000 s for both the non-annealed and nitrogen-annealed BN-based RRAMs. In contrast, the hydrogen-annealed BN-based RRAM showed excellent retention characteristics, with data retained up to 10,000 s.

8.
Inquiry ; 60: 469580231162818, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37039386

RESUMO

The COVID-19 pandemic has transformed undergraduate education into non-face-to-face classes, and a novel methodology is required to aid students in career preparation behavior (CPB). This study aimed to assess the effects of self-rated abilities for health practices (SRAHP) as a psychological attribute and health-promoting lifestyle profile (HPLP) as a behavioral attribute in the dynamics between positive psychological capital (PPC) and CPB among undergraduate students taking non-face-to-face classes. A cross-sectional study was conducted involving 639 undergraduate students taking non-face-to-face classes; data were obtained via online survey in January 2022. A significant positive effect on CPB was observed for PPC (b = 0.261, p < .001) and HPLP (b = 0.674, p < .001). The effect of SRAHP on CPB was not significant; however, it mitigated the PPC-CPB dynamics (b = -.081, p < .05) and strengthened the relationship between HPLP and CPB (b = .250, p < .001). Lastly, the mediating effects after moderation for HPLP and SRAHP were positive, with statistical significance. To aid the students with career preparation in the current undergraduate education environment moving toward a non-face-to-face model, there is a need for resources to increase students' psychological confidence regarding health management and to promote their health practices.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Estudos Transversais , Pandemias , Estudantes/psicologia , Promoção da Saúde , República da Coreia
9.
J Am Soc Echocardiogr ; 36(2): 180-188, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36162771

RESUMO

BACKGROUND: Impaired atrial functional reserve during exercise may represent an early stage of atrial cardiomyopathy. To test this hypothesis, the authors evaluated left atrial (LA) and left ventricular (LV) function reserve during exercise in patients with paroxysmal atrial fibrillation (PAF). METHODS: Sixty-one patients with PAF undergoing radiofrequency catheter ablation and 38 healthy control subjects were prospectively enrolled. LV global longitudinal strain and LA reservoir strain (RS) were measured at rest and during supine bicycle exercise. To identify the early stage of atrial cardiomyopathy without LA structural remodeling, patients with PAF were divided into two groups according to LA volume index (LAVI): atrial fibrillation (AF) group 1 (LAVI ≥ 34 mL/m2) and AF group 2 (LAVI < 34 mL/m2). RESULTS: LV ejection fraction and global longitudinal strain did not differ between patients with AF and control subjects. LAVI and LA RS did not differ between AF group 2 and control subjects. During exercise, LV global longitudinal strain improved in all groups. Increases in LA RS were attenuated in both AF groups, which also exhibited lower LA functional reserve index than the control subjects. Although resting LA RS was similar between AF group 2 and control subjects, LA functional reserve index was significantly lower in AF group 2. LA functional reserve index was associated with risk for AF recurrence (hazard ratio, 0.852; 95% CI, 0.736-0.988). CONCLUSIONS: Atrial cardiomyopathy can be anticipated by impaired LA functional reserve during exercise in patients with AF, even in those with normal-sized left atria. Atrial cardiomyopathy occurs independently of changes in LV function and is associated with the recurrence of AF in patients with PAF after radiofrequency catheter ablation.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Remodelamento Atrial , Cardiomiopatias , Ablação por Cateter , Humanos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Átrios do Coração/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/complicações , Função Ventricular Esquerda
10.
Micromachines (Basel) ; 15(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38258196

RESUMO

Low-power-consumption gas sensors are crucial for diverse applications, including environmental monitoring and portable Internet of Things (IoT) systems. However, the desorption and adsorption characteristics of conventional metal oxide-based gas sensors require supplementary equipment, such as heaters, which is not optimal for low-power IoT monitoring systems. Memristor-based sensors (gasistors) have been investigated as innovative gas sensors owing to their advantages, including high response, low power consumption, and room-temperature (RT) operation. Based on IGZO, the proposed isopropanol alcohol (IPA) gas sensor demonstrates a detection speed of 105 s and a high response of 55.15 for 50 ppm of IPA gas at RT. Moreover, rapid recovery to the initial state was achievable in 50 µs using pulsed voltage and without gas purging. Finally, a low-power circuit module was integrated for wireless signal transmission and processing to ensure IoT compatibility. The stability of sensing results from gasistors based on IGZO has been demonstrated, even when integrated into IoT systems. This enables energy-efficient gas analysis and real-time monitoring at ~0.34 mW, supporting recovery via pulse bias. This research offers practical insights into IoT gas detection, presenting a wireless sensing system for sensitive, low-powered sensors.

11.
Int J Heart Fail ; 4(1): 42-53, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36262195

RESUMO

Background and Objectives: Left atrial (LA) fibrosis is an important component of the arrhythmogenic substrate and is related to LA dysfunction in patients with atrial fibrillation (AF). However, its relationship with functional changes and the risk of thrombus in patients with paroxysmal AF (PAF) and persistent AF (PeAF) remains unclear. Methods: We included 139 patients with preprocedural cardiac magnetic resonance imaging (CMR) and transesophageal echocardiography (TEE) for the first AF catheter ablation. Spontaneous echo contrast (SEC) and multiple parameters of LA were measured from TEE and CMR. LA fibrosis was evaluated by late gadolinium enhancement of LA (LA-LGE) of CMR. Results: The presence of SEC was higher in patients with PeAF than in patients with PAF (26.4% vs. 11.9%, p=0.03). The patients with SEC had more enlarged LA size and impaired function of LA and LAA, regardless of AF type. However, the area of LA-LGE was more extensive in patients with SEC in PeAF (27.5±15.9 vs. 20.1±10.3, p=0.033), not in PAF. In PAF, maximal LA volume index was closely related to the presence of SEC with marginal trend toward significance (odd ratio [OR], 1.07; 95% confidence interval [CI], 0.99-1.16; p=0.072). Whereas, a larger area of LA-LGE and lower emptying flux of LA appendage were independently related with SEC (OR, 1.10; 95% CI, 1.0-1.20; p=0.049 and OR, 0.93; 95% CI, 0.86-0.99; p=0.022, respectively) after adjusting related cardiovascular risk factors of SEC. Conclusions: In this study, we suggest that the risk of thrombus is provoked by LA enlargement with dysfunction in early-stage AF and by stiffened LA with fibrosis rather than LA size when it becomes PeAF.

12.
Eur Heart J Open ; 2(4): oeac008, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36117949

RESUMO

Aims: Chemotherapy-induced cardiotoxicity (CIC) is a significant complication, meanwhile myocardial damage might differ depending on chemotherapy agents and their timing. The aim of this study was to evaluate serial changes of layer-specific myocardial function in patients with breast cancer and their differences by the development time of CIC and chemotherapy agent. Methods and results: A total of 105 consecutive patients with breast cancer (age: 52.3 ± 9.3 years) were enrolled. Chemotherapy-induced cardiotoxicity occurred in 20 (19%) patients during 6 months. Endocardial and midmyocardial functions decreased in patients with or without CIC, with patients with CIC showing greater decreases during follow-up. Global longitudinal strain (GLS) change at 3 months was the most sensitive parameter to detect CIC. When new development of CIC was analysed at 6 months, GLS was reduced earlier than the decrease of left ventricular ejection fraction. In patients with CIC who were treated with anthracycline-based regimen for 3 months, endocardial GLS markedly decreased at 3 months and continued to decrease until 6 months. Patients with CIC who received trastuzumab therapy after anthracycline therapy showed further reduction in endocardial GLS at the 6-month follow-up, which was not shown in patients with CIC who received taxane therapy subsequently. Conclusion: Myocardial function assessed by strain decreased in all patients with breast cancer receiving chemotherapy. The endocardial layer was the most vulnerable to chemotherapy-induced myocardial damage. Functional impairment was more profound in patients with CIC who received sequential anthracycline-trastuzumab chemotherapy. Thus, early evaluation of left ventricular function might be necessary for all patients with breast cancer to detect CIC.

13.
ACS Sens ; 7(9): 2567-2576, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-35981971

RESUMO

Oxygen (O2) sensing in trace amounts and mixed gas is essential in many types of industries. Semiconductor sensors have proven to be invaluable tools for the O2 measurements in a wide concentration range, but the sensors are only able to quantify O2 in a concentration range of subppm, thus far, especially in mixed gas. We present in this paper a new concept for O2 sensing with incomparable sensitivity using IGZO-films with oxygen vacancy-based conducting filaments (CFs). O2 sensing relies on rupturing of the CFs, and the proposed device quickly recovers to the initial state using a pulse of 0.6 V/90 µs after the sensing. The proposed device has a high sensitivity of 14 even at an O2 concentration of 500 ppb, a detection limit of 150 ppb for O2 at RT, and excellent selectivity for O2 in mixed gas, which is remarkable compared to other gas sensors. The proposed device can be widely used in gas sensors especially for detecting O2 at a low ppb level, which is due to excellent sensing characteristics.


Assuntos
Gases , Humanos , Oxigênio , Temperatura
14.
Nat Commun ; 13(1): 2804, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589720

RESUMO

Algorithms for intelligent drone flights based on sensor fusion are usually implemented using conventional digital computing platforms. However, alternative energy-efficient computing platforms are required for robust flight control in a variety of environments to reduce the burden on both the battery and computing power. In this study, we demonstrated an analog-digital hybrid computing platform based on SnS2 memtransistors for low-power sensor fusion in drones. The analog Kalman filter circuit with memtransistors facilitates noise removal to accurately estimate the rotation of the drone by combining sensing data from the gyroscope and accelerometer. We experimentally verified that the power consumption of our hybrid computing-based Kalman filter is only 1/4th of that of the traditional software-based Kalman filter.

15.
Clin Ther ; 44(5): 698-709, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35410755

RESUMO

PURPOSE: LDL-lowering therapy is beneficial to reduce the risk of cardiovascular disease (CVD). Higher statin doses lower LDL-C levels and prevent CVD; however, they increase adverse events, such as muscle-related adverse events and new-onset diabetes mellitus (DM). Ezetimibe combined with statin therapy improves LDL-C-lowering levels and tolerability in patients with established CVD. We aimed to analyze the efficacy and safety of a fixed-dose rosuvastatin and ezetimibe (R+E) combination therapy in intermediate-risk patients with hypercholesterolemia and no DM after 12 months of visiting a primary physician. METHODS: This multicenter, open-label, single-arm, prospective observational study involved 5717 patients from 258 primary health care centers in Korea enrolled between 2016 and 2018. Patients had no DM or previous CVD but had cardiovascular risk factors and were taking a statin or a fixed-dose combination of E (10 mg) + R (5, 10, or 20 mg). We analyzed 700 patients using propensity score matching. FINDINGS: A fixed-dose R+E combination therapy significantly reduced LDL-C in 5/10 mg R+E (29.35%), 10/10 mg R+E (36.19%), and 20/10 mg R+E (41.83%) compared with statin monotherapy (19.09%) at 12-month follow-up (P = 0.017). Compared with statin monotherapy, HDL-C levels increased in 5/10 mg R+E (mean change at 12 months; P = 0.004), and triglyceride levels decreased in 10/10 mg R+E (mean change at 12 months; P = 0.033). The fixed-dose R+E combination therapy was associated with fewer adverse events and a neutral effect on glucose deterioration compared with statin monotherapy at 12 months of follow-up. IMPLICATIONS: In a possible paradigm shift, a fixed-dose R+E combination therapy may be beneficial for primary cardiovascular prevention with potent LDL-lowering efficacy and tolerability; however, further large prospective studies are needed.


Assuntos
Anticolesterolemiantes , Doenças Cardiovasculares , Diabetes Mellitus , Dislipidemias , Inibidores de Hidroximetilglutaril-CoA Redutases , Doenças Cardiovasculares/etiologia , LDL-Colesterol , Estudos de Coortes , Diabetes Mellitus/tratamento farmacológico , Quimioterapia Combinada , Dislipidemias/diagnóstico , Dislipidemias/tratamento farmacológico , Ezetimiba/efeitos adversos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Atenção Primária à Saúde , Rosuvastatina Cálcica
16.
ACS Sens ; 6(11): 4217-4224, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34783247

RESUMO

Fast recovery, high sensitivity, high selectivity, and room temperature (RT) sensing characteristics of NO gas sensors are essential for environmental monitoring, artificial intelligence, and inflammatory diagnosis of asthma patients. However, the conventional semiconductor-type gas sensors have poor sensing characteristics that need to be solved, such as slow recovery speeds (>360 s), low sensitivity (3.8), and high operating temperatures (>300 °C). We propose here a memristor-based NO gas sensor as a gasistor (gas sensor + memory resistor) with SnO2, Ta2O5, and HfO2 films, which successfully demonstrated the feasibility of fast reaction/recovery (<1 s/90 ns) and high sensitivities such as 11.66 and 5.22 in Ta2O5 and HfO2 gasistors for NO gas, at RT. Furthermore, so as to reinforce the selectivity in multigas ambient, we suggest a parallel circuit using three kinds of gasistors having different sensitivities for NO, O2, and C2H6 gases, which results in an improvement of selectivity for the selected gas at RT.


Assuntos
Inteligência Artificial , Gases , Humanos , Semicondutores , Temperatura
17.
Diabetes Metab J ; 45(5): 719-729, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34126709

RESUMO

BACKGROUND: Metabolic syndrome (MetS) is closely associated with the aging process. However, changes in metabolic conditions and cardiac function that occur in middle aged population remain unclear. We evaluated longitudinal changes in metabolic parameters and cardiac function during a 3-year period in subjects with suspected MetS. METHODS: We studied 191 participants with suspected MetS at baseline and after 3 years. Anthropometric parameters, including waist circumference (WC), and metabolic parameters, including fasting blood glucose and lipid profile were measured. Conventional echocardiography with two-dimensional speckle tracking was performed. RESULTS: Mean age was 56.2±4.4 years, and there were 97 women (50.8%). Men had increased WC and triglycerides (TG) (WC 91.2±6.8 cm vs. 84.0±8.0 cm, P<0.001; TG 184.4±116.3 mg/dL vs. 128.2±53.6 mg/dL, P<0.001), and reduced global longitudinal strain (GLS) (-15.4%±2.1% vs. -17.1%±2.0%, P<0.001) compared to women. After 3.4 years, values of WC and TG did not change in men but increased in women (all P<0.05). The absolute value of left ventricular (LV) GLS did not change in men but was reduced in women (P=0.011). Change in TG was independently associated with worsening of LV GLS only in women (standardized ß, -0.309; 95% confidence interval, -0.130 to -0.009; P=0.025). CONCLUSION: In middle aged population, a vulnerable period for metabolic disturbance, cardiac remodeling tended to progress, which was prominent in women. Progression of adiposity and dyslipidemia after menopause may accelerate subclinical cardiac remodeling in middle-aged women. Lifestyle modification and medical interventions may help prevent further cardiac dysfunction in these subjects.


Assuntos
Síndrome Metabólica , Adiposidade , Feminino , Seguimentos , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Miocárdio , Circunferência da Cintura
18.
Sci Rep ; 11(1): 10513, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006974

RESUMO

Identification of obstructive coronary artery disease (OCAD) in patients with chest pain is a clinical challenge. The value of corrected QT interval (QTc) for the prediction of OCAD has yet to be established. We consecutively enrolled 1741 patients with suspected angina. The presence of obstructive OCAD was defined as ≥ 50% diameter stenosis by coronary angiography. The pre-test probability was evaluated by combining QTc prolongation with the CAD Consortium clinical score (CAD2) and the updated Diamond-Forrester (UDF) score. OCAD was detected in 661 patients (38.0%). QTc was longer in patients with OCAD compared with those without OCAD (444 ± 34 vs. 429 ± 28 ms, p < 0.001). QTc was increased by the severity of OCAD (P < 0.001). QTc prolongation was associated with OCAD (odds ratio (OR), 2.27; 95% confidence interval (CI), 1.81-2.85). With QTc, the C-statistics increased significantly from 0.68 (95% CI 0.66-0.71) to 0.76 (95% CI 0.74-0.78) in the CAD2 and from 0.64 (95% CI 0.62-0.67) to 0.74 (95% CI 0.72-0.77) in the UDF score, respectively. QT prolongation predicted the presence of OCAD and the QTc improved model performance to predict OCAD compared with CAD2 or UDF scores in patients with suspected angina.


Assuntos
Dor no Peito/fisiopatologia , Doença da Artéria Coronariana/fisiopatologia , Adulto , Doença da Artéria Coronariana/diagnóstico por imagem , Eletrocardiografia , Feminino , Humanos , Síndrome do QT Longo/diagnóstico por imagem , Síndrome do QT Longo/fisiopatologia , Masculino , Pessoa de Meia-Idade
19.
PLoS One ; 16(1): e0244723, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33411816

RESUMO

BACKGROUND: Complex antithrombotic regimens are recommended for patients with atrial fibrillation (AF) undergoing drug-eluting stent (DES) implantation but carry high bleeding risk. HYPOTHESIS: We aimed to evaluate whether left atrial appendage occlusion (LAAO) with dual antiplatelet therapy (DAPT) improve clinical outcomes when compared with multiple antithrombotic therapy (MAT) in patients with AF undergoing DES implantation. METHODS: Among 475 AF patients who underwent DES, 41 patients treated by LAAO with DAPT and 434 patients on MAT were compared. MAT was defined as any combination of warfarin-based antithrombotic therapy. Among the MAT group, 34.8% were on triple antithrombotic therapy. The primary endpoint was a net adverse clinical event (NACE), a composite of cerebrovascular accident (CVA) and major bleeding. Secondary endpoints were CVA, major bleeding, major adverse cardiac and cerebral event (MACCE), MI, cardiovascular death, and all-cause death. Additional analysis between the new oral anticoagulant (NOAC)-based antithrombotic therapy group (n = 45) and the LAAO group was performed for the same endpoints. To adjust the confounding factors, inverse probability of treatment weighting (IPTW) was applied during the endpoint analysis. RESULTS: The LAAO group showed higher incidences of diabetes mellitus, prior CVA, higher CHA2DS2-VASc score (4.56±1.55 vs. 2.96±1.60; P<0.0001), and higher HAS-BLED score (3.24±1.20 vs. 2.13±0.75; P<0.0001). NACE occurred less frequently in the LAAO group than the MAT group at 24 months (9.4% vs. 15.3%; hazard ratio 0.274; 95% confidence interval 0.136 - 0.553; P = 0.0003), mainly driven by the reduction in major bleeding (2.4% vs. 9.3%; hazard ratio 0.119; 95% confidence interval 0.032 - 0.438; P = 0.001). The LAAO group with greater thrombotic and hemorrhagic risks showed comparable primary/secondary outcomes with the NOAC-based anti-thrombotic therapy group. CONCLUSIONS: Among patients with AF who underwent DES implantation, the LAAO group had better net clinical outcomes for preventing CVA and major bleeding than the MAT group. Further large-scale trials including comparisons with NOACs are warranted.


Assuntos
Fibrilação Atrial/cirurgia , Doença da Artéria Coronariana/cirurgia , Stents Farmacológicos/efeitos adversos , Terapia Antiplaquetária Dupla , Fibrinolíticos/uso terapêutico , Hemorragia/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/tratamento farmacológico , Doença da Artéria Coronariana/tratamento farmacológico , Feminino , Humanos , Masculino , Resultado do Tratamento
20.
Nanoscale ; 12(3): 2040-2046, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31912838

RESUMO

Brain-inspired neuromorphic computing has the potential to overcome the inherent inefficiency of the conventional von Neumann architecture by using the massively parallel processing power of artificial neural networks. Neuromorphic parallel processing can be implemented naturally using the crossbar geometry of synaptic device arrays with Ohm's and Kirchhoff's laws. However, selective and parallel weight updates of the synaptic crossbar array are still very challenging due to the unavoidable crosstalk between adjacent devices and sneak path currents. Here, we experimentally demonstrate a weight update protocol in a carbon nanotube synaptic transistor array, where selective and parallel weight updates can be executed by exploiting the individually controllable three terminals of the synaptic device via a localized carrier trapping mechanism. The trained 9 × 8 synaptic array solves four different convolution operations simultaneously for the feature extraction of an image. The massive parallelism and robustness of the weight update protocol are important features toward effective manipulation of big data through neuromorphic computing systems.

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