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1.
Sensors (Basel) ; 18(9)2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30205504

RESUMO

In this research, we developed a wearable temperature-sensing element by dip dyeing threads in poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) (p-type conducting polymer) solution. The PEDOT:PSS was used to dye the textile and it exhibited negative temperature coefficient characteristics in which the resistance decreases as the temperature increases. The fabricated temperature-detection thread achieved a sensitivity of 167.1 Ω/°C with 99.8% linearity in the temperature range of -50 °C to 80 °C. We anticipate that temperature sensors that apply our technology will be made as stitch- or textile-type for wearable devices, and they will be widely adopted for different applications such as in fitness, leisure, healthcare, medical treatment, infotainment, industry, and military applications, among others.


Assuntos
Polímeros/química , Temperatura , Têxteis , Dispositivos Eletrônicos Vestíveis , Humanos
2.
Thromb Haemost ; 115(1): 213-21, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26581884

RESUMO

Addition of a potent P2Y12 inhibitor to aspirin is the standard therapy for non-ST-segment elevation acute coronary syndrome (NSTE-ACS) patients undergoing percutaneous coronary intervention (PCI). Glycoprotein IIb/IIIa inhibitor, together with antiplatelet therapy, may be considered as part of initial therapy in NSTE-ACS patients with high-risk features. This study investigated the antiplatelet effect of ticagrelor loading dose (LD) versus tirofiban bolus injection with a post-bolus infusion on top of aspirin among NSTE-ACS patients planned to PCI. NSTE-ACS patients were randomised to receive either ticagrelor (n = 47) or tirofiban (n = 48). Platelet reactivity was assessed by light transmittance aggregometry at 0, 2, 8, and 24 hours (h) after treatment initiation. Primary endpoint was inhibition of platelet aggregation (IPA, 20 µM ADP, final extent) at 2 h after LD therapy, with a non-inferiority margin of 10%. The prevalence of high on-treatment platelet reactivity (HPR) was also compared at 0, 2, 8, and 24 h. The mean difference in IPA between ticagrelor and tirofiban was -9.9% (95% confidence interval: -25.7% to 5.9%) at 2 h, -1.6% (-8.0% to 4.8%) at 8 h, and -3.3% (-18.4% to 12.0%) at 24 h. The prevalence of HPR did not differ between the two groups at any time point (all p values ≥ 0.059), which was almost abolished by 8 h post-LD (< 5%). In conclusion, the antiplatelet effect during the early phase (~2 h) after ticagrelor LD appeared to be relatively strong, but it did not reach that of tirofiban in NSTE-ACS patients.


Assuntos
Síndrome Coronariana Aguda/terapia , Adenosina/análogos & derivados , Aspirina/administração & dosagem , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Tirosina/análogos & derivados , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico , Adenosina/administração & dosagem , Adenosina/efeitos adversos , Idoso , Aspirina/efeitos adversos , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Testes de Função Plaquetária , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , República da Coreia , Ticagrelor , Fatores de Tempo , Tirofibana , Resultado do Tratamento , Tirosina/administração & dosagem , Tirosina/efeitos adversos
3.
Korean Circ J ; 42(11): 792-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23236335

RESUMO

The combination of coronary arteriovenous fistula to the coronary sinus (CS), dilatation of the entire length of coronary artery, coronary aneurysm and persistent left superior vena cava (PLSVC) is very rare. We present the case of a 63-year-old female admitted for dyspnea on exertion, orthopnea, and facial edema. Echocardiography detected a giant coronary artery with shunt flow, dilated CS and PLSVC and a coronary angiography reaffirmed these findings. The calculated ratio of pulmonary blood flow to systemic blood flow by cardiac catheterization was 1.53. After multidisciplinary review considering old age, hypoactivity due to underlying Parkinsonism and relatively small amount of shunt flow, medical therapy was chosen. The patient remained asymptomatic for 10 months after discharge without intervention.

4.
Korean Circ J ; 42(10): 722-3, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23170104
5.
Korean Circ J ; 42(9): 632-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23091510

RESUMO

Herein, we present a case of a successful catheter ablation of ventricular tachycardia (VT) using a radial artery approach in a post-myocardial infarction patient, who had an implantable cardioverter-defibrillator and peripheral artery disease. Although the patient did not use antiarrhythmic drugs, the patient experienced no recurrence of VT during the following 3-year period.

6.
Catheter Cardiovasc Interv ; 80(4): 581-9, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21805603

RESUMO

OBJECTIVES: We assess microvascular integrity as a marker of myocardial viability after coronary stenting, using only a pressure guidewire. BACKGROUND: Microvascular integrity generally is not assessed using pressure-only guidewires because the transducer lies upstream of microvasculature. We partially inflate a balloon inside a coronary stent to achieve a specific normalized pressure drop at rest (distal coronary/aortic pressure = 0.8) and then infuse a vasodilator, to render the wire sensitive to microvascular function. We hypothesize that the further decline in pressure (ΔFFR(0.8) ) predicts MRI myocardial viability. METHODS: We studied 29 subjects with acute coronary syndrome including myocardial infarction. After successful culprit stenting, the resting coronary/aortic pressure was set to 0.8 using temporary balloon obstruction. ΔFFR(0.8) was defined as 0.8-(distal coronary/aortic pressures) during adenosine-induced hyperemia. The average transmural extent of infarction was defined as the average area of MRI late gadolinium enhancement (after 2.8 ± 1.5 days) divided by the corresponding full thickness of the gadolinium enhanced sector in short axis slices, and was compared with ΔFFR(0.8) . RESULTS: ΔFFR(0.8) corresponded inversely and linearly with the average transmural extent of infarction (r(2) = 0.65, P < 0.001). We found that a transmural extent of infarction of 0.50 corresponded to a ΔFFR(0.8) threshold of 0.1, and had high sensitivity and specificity (100% and 94.4%, respectively). CONCLUSIONS: Using only an upstream pressure-sensitive guidewire and a partially obstructing balloon during pharmacologic hyperemia, we were able to predict MRI myocardial viability with high accuracy after relief of epicardial stenosis. With further validation, this may prove a useful clinical prognostic tool after percutaneous intervention.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Angioplastia Coronária com Balão , Cateterismo Cardíaco , Reserva Fracionada de Fluxo Miocárdico , Microcirculação , Infarto do Miocárdio/diagnóstico , Miocárdio/patologia , Resistência Vascular , Síndrome Coronariana Aguda/patologia , Síndrome Coronariana Aguda/fisiopatologia , Síndrome Coronariana Aguda/terapia , Adenosina , Idoso , Angioplastia Coronária com Balão/instrumentação , Pressão Sanguínea , Calibragem , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/normas , Cateteres Cardíacos , Distribuição de Qui-Quadrado , Feminino , Humanos , Hiperemia/fisiopatologia , Modelos Lineares , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Stents , Sobrevivência de Tecidos , Transdutores de Pressão , Resultado do Tratamento , Vasodilatadores
7.
Acta Radiol ; 52(8): 860-5, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21873509

RESUMO

BACKGROUND: With increasing awareness for radiation exposure, the study of diagnostic accuracy of coronary CT angiography (CCTA) with low radiation dose techniques is mandatory to both radiologist and clinician. PURPOSE: To compare diagnostic performance and effective radiation dose between step-and-shoot prospectively ECG-gated and retrospectively ECG-gated with tube current modulation (TCM) CCTA using 128-slice multidetector computed tomography (MDCT). MATERIAL AND METHODS: We retrospectively evaluated 60 patients who underwent CCTA with either of two different low-dose techniques using 128-slice MDCT (23 patients for step-and shoot-prospectively ECG-gated and 37 patients for retrospectively ECG-gated with TCM CCTA) followed by conventional coronary angiography. All coronary arteries and all segments thereof, except anatomical variants or small size (< 1.5 mm) ones, were included in analysis. RESULTS: In per-segment analysis, sensitivity, specificity, positive predictive value, and negative predictive value were 91/96%, 95/94%, 75/73%, and 98/99% for step-and-shoot prospectively ECG-gated and retrospectively ECG gated with TCM CCTA, respectively, relative to conventional coronary angiography. Effective radiation dose were 1.75 ± 0.83 mSv, 4.91 ± 1.71 mSv in the step-and-shoot prospectively ECG-gated and retrospectively ECG-gated with TCM CCTA groups, respectively. CONCLUSION: The two low-radiation dose CCTA techniques using 128-slice MDCT yields comparable diagnostic performance for coronary artery disease in symptomatic patients with low heart rates.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Dor no Peito/diagnóstico por imagem , Angiografia Coronária/métodos , Doença das Coronárias/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Distribuição de Qui-Quadrado , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Sensibilidade e Especificidade
8.
Macromol Rapid Commun ; 32(14): 1047-51, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21648002

RESUMO

Fluorescence (FL) emission properties, microporous structures, energy-minimized chain conformations, and lamellar layer structures of the silicon-containing poly(diphenylacetylene) derivative of p-PTMSDPA before and after desilylation were investigated. The nitrogen-adsorption isotherms of p-PTMSDPA film before and after desilylation were typical of type I, indicating microporous structures. The BET surface area and pore volume of the p-PTMSDPA film were significantly reduced after the desilylation reaction, simultaneously, its FL emission intensity remarkably decreased. The theoretical calculation on both model compounds of p-PTMSDPA and its desilylated polymer, PDPA, showed a remarkable difference in chain conformation: The side phenyl rings of p-PTMSDPA are discontinuously arranged in a zig-zag pattern, while the PDPA is continuously coiled in a helical manner. The lamellar layer distance (LLD) in the p-PTMSDPA film significantly decreased after the desilylation reaction.


Assuntos
Acetileno/análogos & derivados , Polímeros/química , Acetileno/química , Fluorescência , Estrutura Molecular , Polímeros/síntese química , Porosidade , Silício/química
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