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1.
J Atheroscler Thromb ; 2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33814487

RESUMO

We have a great interest in the article in Journal of Atherosclerosis and Thrombosis by Suzuki et al. titled Complex Aortic Arch Atherosclerosis in Acute Ischemic Stroke Patients with Non-Valvular Atrial Fibrillation. The authors demonstrated that 38.7% transesophageal echocardiography-derived complex aortic arch plaques (CAPs) among 106 patients with acute ischemic strokes with atrial fibrillation (AF), suggesting that patients with acute ischemic stroke and AF often had CAPs. The atheromatous lesions at the aortic arch are one of the causes of ischemic strokes. The cause of acute ischemic strokes in patients with AF could not only be cardiogenic embolisms due to AF but also aortogenic embolisms due to CAPs. The possibility of concomitant CAPs should be considered for stroke patients with AF. Non-obstructive general angioscopy has the possibility to detect aortic plaques in the aortic arch more accurately than TEE and might help to diagnose atheromatous plaques and embolic materials in the aortic arch. Further studies are needed to elucidate the causes of ischemic strokes and are expected to improve the outcomes for acute ischemic strokes in patients with AF.

2.
J Atheroscler Thromb ; 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33658453

RESUMO

AIM: Coronary plaque rupture is the main cause of acute coronary syndrome (ACS), but the role of blood flow features around plaque rupture for ACS is still unknown. The present study aimed to assess the relationship between the geometric configuration of ruptured plaque and ACS occurrence using computational fluid dynamics (CFD) by moving particle method in patients with coronary artery disease. METHODS: In this study, 45 patients with coronary artery disease who underwent three-dimensional intravascular ultrasound (IVUS) and had a coronary ruptured plaque (24 plaques with provoked ACS, 21 without) were included. To compare the difference in blood flow profile around ruptured plaque between the patients with and without ACS, the IVUS images were analyzed via the novel CFD analysis. RESULTS: There were no significant differences in localized flow profile around ruptured plaque between the two groups when the initial particle velocity was 10.0 cm/s corresponded to a higher coronary flow velocity at ventricular diastole. However, when it was 1.0 cm/s corresponded to lower coronary flow velocity at ventricular systole, particles with lower velocity (0 ≤ V ≤ 5 cm/s) were more prevalent around ACS-PR (p=0.035), whereas particles with higher velocity (10 ≤ V ≤ 20 cm/s) were more often detected in silent plaque ruptures (p=0.018). CONCLUSIONS: Three-dimensional IVUS revealed that coronary plaque rupture was a complex one with a wide variety of its stereoscopic configuration, leading to various patterns of the local coronary flow profile. A novel CFD analysis suggested that the local flow was more stagnant around ACS-provoked ruptures than in silent ones.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33665702

RESUMO

Non-obstructive general angioscopy (NOGA) images of severe aortic valve stenosis (AS) and atherosclerotic aorta were documented. Atheromatous embolization is known as an important complication of endovascular therapy for severe AS. However, it is hard to detect atherosclerotic changes of the aortic valve and atheromatous aorta related to them in the in-vivo setting. NOGA, which is a novel imaging modality for the aorta and aortic valves, can visualize atherosclerosis of aortic intima vividly. NOGA may play a role in risk stratification for atheromatous embolism with endovascular therapy. We reported a case of severe AS and atheromatous aorta to evaluate before an operation with NOGA.

4.
Heart Vessels ; 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33743048

RESUMO

There are a few Japanese data regarding the incidence and outcomes of acute myocardial infarction (AMI) after the coronavirus disease 2019 (COVID-19) outbreak. We retrospectively reviewed the data of AMI patients admitted to the Nihon University Itabashi Hospital after a COVID-19 outbreak in 2020 (COVID-19 period) and the same period from 2017 to 2019 (control period). The patients' characteristics, time course of admission, diagnosis, and treatment of AMI, and 30-day mortality were compared between the two period-groups for both ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI), respectively. The AMI inpatients decreased by 5.7% after the COVID-19 outbreak. There were no differences among most patient backgrounds between the two-period groups. For NSTEMI, the time from the symptom onset to admission was significantly longer, and that from the AMI diagnosis to the catheter examination tended to be longer during the COVID-19 period than the control period, but not for STEMI. The 30-day mortality was significantly higher during the COVID-19 period for NSTEMI (23.1% vs. 1.9%, P = 0.004), but not for STEMI (9.4% vs. 8.3%, P = 0.77). In conclusion, hospitalizations for AMI decreased after the COVID-19 outbreak. Acute cardiac care for STEMI and the associated outcome did not change, but NSTEMI outcome worsened after the COVID-19 outbreak, which may have been associated with delayed medical treatment due to the indirect impact of the COVID-19 pandemic.

5.
J Atheroscler Thromb ; 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33746158

RESUMO

AIMS: Smaller low-density lipoprotein (LDL) particle size has been suggested to result in the development of endothelial dysfunction, atherosclerosis, and in-stent restenosis (ISR); however, little is known regarding the impact of the LDL particle size on the neointima formation leading to ISR after everolimus-eluting stent (EES) implantation. METHODS: In this study, we have included 100 patients to examine the relationship between an LDL-C/apolipoprotein B (Apo B) ≤ 1.2, reportedly representing the LDL particle size, and the neointimal characteristics using optical coherence tomography (OCT) and coronary angioscopy (CAS) during the follow-up coronary angiography (CAG) period (8.8±2.5 months) after EES implantation. We divided them into two groups: LDL-C/Apo B ≤ 1.2 group (low LDL-C/Apo B group, n=53) and LDL-C/Apo B >1.2 group (high LDL-C/Apo B group, n=47). RESULTS: The low LDL-C/Apo B group had a significantly larger neointimal volume (12.8±5.3 vs. 10.3±4.9 mm3, p=0.021) and lower incidence of a neointimal homogeneous pattern (71 vs. 89 %), higher incidence of a neointimal heterogeneous pattern (25 vs. 9 %) (p=0.006) and higher prevalence of macrophage accumulation (9 vs. 2 %) (p=0.030) as assessed via OCT, and, as per the CAS findings, a higher prevalence of yellow grade ≥ 2 (grade 2; adjusted residual: 2.94, grade 3; adjusted residual: 2.00, p=0.017) than the high LDL-C/Apo B group. CONCLUSIONS: A low LDL-C/Apo B ratio was found to be strongly associated with neointimal proliferation and neointimal instability evidenced chronically by OCT and CAS. An LDL-C/Apo B ≤ 1.2 will be of aid in terms of identifying high-risk patients after EES implantation.

6.
Atherosclerosis ; 319: 62-71, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33486352

RESUMO

BACKGROUND AND AIMS: The optimal duration of dual antiplatelet therapy for acute myocardial infarction is controversial because the bleeding risk outweighs the thromboembolic risk. We hypothesized that an in-stent thrombus (IS-thrombus) detected by coronary angioscopy (CAS) after stent implantation would be associated with high bleeding risk. METHODS: This study included 208 patients who underwent CAS at 2 weeks after stent implantation for an acute myocardial infarction. The study was approved by the ethics committee at the Nihon University Itabashi Hospital (reference number RK-200714-10). RESULTS: In 84 patients, in whom no IS-thrombus was identified in the culprit vessel using CAS, the major bleeding event rate was significantly higher than that in patients with IS-thrombi (n = 124). However, no difference was detected in major adverse cardiovascular events (MACE; stroke, hospitalization for a non-fatal myocardial infarction/unstable angina, target lesion revascularization, and cardiovascular death). After adjustments by the propensity score based on patient characteristics, the absence of IS-thrombi remained an independent predictor of major bleeding events (hazard ratio 4.73, 95% confidence interval 2.04-11.00, p < 0.001). CONCLUSIONS: The absence of CAS-detected IS-thrombi in the subacute phase was independently associated with future major bleeding events, but not with MACE. These findings may help optimize the duration of dual antiplatelet therapy.

7.
Opt Express ; 28(25): 37798-37810, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33379608

RESUMO

Swept-source optical coherence tomography (OCT) typically relies on expensive and complex swept-source lasers, the cost of which currently limits the suitability of OCT for new applications. In this work, we demonstrate spectrally sparse OCT utilizing randomly spaced low-bandwidth optical chirps, suitable for low-cost implementation with telecommunications grade devices. Micron scale distance estimation accuracy with a resolution of 40 µm at a standoff imaging distance greater than 10 cm is demonstrated using a stepped chirp approach with approximately 23% occupancy of 4 THz bandwidth. For imaging of sparse scenes, comparable performance to full bandwidth occupancy is verified for metallic targets.

8.
J Atheroscler Thromb ; 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33012739

RESUMO

AIMS: Wall shear stress (WSS) has been considered a major determinant of aortic atherosclerosis. Recently, non-obstructive general angioscopy (NOGA) was developed to visualize various atherosclerotic pathologies, including in vivo ruptured plaque (RP) in the aorta. However, the relationship between aortic RP and WSS distribution within the aortic wall is unclear. This study aimed to investigate the relationship between aortic NOGA-derived RP and the stereographic distribution of WSS by computational fluid dynamics (CFD) modeling using three-dimensional computed tomography (3D-CT) angiography. METHODS: We investigated 45 consecutive patients who underwent 3D-CT before coronary angiography and NOGA during coronary angiography. WSS in the aortic arch was measured by CFD analysis based on the finite element method using uniform inlet and outlet flow conditions. Aortic RP was detected by NOGA. RESULTS: Patients with a distinct RP showed a significantly higher maximum WSS value in the aortic arch than those without aortic RP (56.2±30.6 Pa vs 36.2±19.8 Pa, p=0.017), no significant difference was noted in the mean WSS between those with and without aortic RP. In a multivariate logistic regression analysis, the presence of a maximum WSS value more than a specific value was a significant predictor of aortic RP (odds ratio 7.21, 95% confidence interval 1.78-37.1, p=0.005). CONCLUSIONS: Aortic RP detected by NOGA was strongly associated with a higher maximum WSS in the aortic arch derived by CFD using 3D-CT. The maximum WSS value may have an important role in the underlying mechanism of not only aortic atherosclerosis, but also aortic RP.

9.
Int J Chron Obstruct Pulmon Dis ; 15: 2115-2126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982204

RESUMO

Background: Comparative effects on physical activity of mono and dual bronchodilators remain unclear in patients with treatment-naïve chronic obstructive pulmonary disease (COPD). We sought to compare the changes in physical activity before and after tiotropium and tiotropium/olodaterol treatment in treatment-naïve COPD patients. Methods: A prospective, multicenter, randomized, open-labeled, and parallel interventional study was conducted. Eighty Japanese patients with treatment-naïve COPD were randomized to receive either tiotropium or tiotropium/olodaterol treatment for 12 weeks. Spirometry and dyspnea index were assessed, and COPD assessment test (CAT) and the 6-minute walk distance (6MWD) were conducted before and after treatment. Evaluation of physical activity was assessed by a triaxle accelerometer over a 2-week period before and after treatment. Results: There were no differences in the mean age (69.8 vs 70.4 years), body mass index (BMI) (22.5 vs 22.6 kg/m2) and mean % forced expiratory volume in 1 second (%FEV1) at baseline (61.5 vs 62.6%) between the two groups. Changes in FEV1 (mean±standard error, 242.8±28.8 mL) and transient dyspnea index (TDI) (2.4±0.3 points) before and after tiotropium/olodaterol treatment were greater than with tiotropium treatment (104.1±31.9 mL, p<0.01 and 1.5±0.3, p=0.02, respectively). Changes in the duration of physical activity with 1.0-1.5 metabolic equivalents (METs) estimated in the sedentary position following tiotropium/olodaterol treatment (-38.7±14.7 min) tended to be reduced more than with tiotropium treatment (-4.6±10.6 min) (p=0.06), although those with ≥2.0 METs numerically increased with both treatments (+10.8±7.6 min for tiotropium/olodaterol vs +8.3±7.6 min for tiotropium, p=0.82). Tiotropium/olodaterol treatment reduced the duration of physical activity with 1.0-1.5 METs (regression coefficient, -43.6 [95% CI -84.1, -3.1], p=0.04) in a multiple regression model adjusted for cofounding factors such as age, FEV1, total CAT scores, 6MWD, and TDI. Conclusion: This is the first study to report the impact of dual bronchodilator on physical activity in treatment-naïve COPD patients of Japanese with low BMI.

11.
Atherosclerosis ; 292: 127-135, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31805452

RESUMO

BACKGROUND AND AIMS: Elevated pentraxin-3 (PTX3) values are associated with vulnerable plaque existence and poor outcomes in acute coronary syndrome patients. The clinical significance of PTX3 values in stable angina pectoris (SAP) patients is, however, undetermined. We investigated the relationship of systemic PTX3 values and coronary plaque components and post-percutaneous coronary intervention (PCI) outcomes in SAP patients. METHODS: We included 93 consecutive de-novo lesions in 93 SAP patients with a normal pre-PCI high-sensitivity cardiac troponin-T (<0.014 ng/mL), undergoing pre- and post-PCI optical coherence tomography (OCT). Systemic PTX3 values were obtained immediately pre- and post-PCI, at 24-h and 9-month post-PCI. RESULTS: Peak post-PCI PTX3 values correlated with thinnest fibrous cap thickness (r = -0.23, p = 0.03) and lipid length (r = 0.24, p = 0.03), and were higher in patients with lesions having OCT-derived thin-cap fibroatheroma (6.67 (3.19-7.33) vs. 3.13 (2.34-4.11) ng/mL, p = 0.04) and post-stenting irregular tissue protrusion (4.76 (3.31-6.80) vs. 2.98 (2.23-4.06) ng/mL, p = 0.003) than in those without. At 9-month follow-up, cardiac event-free survival was poorer in patients with a peak post-PCI PTX3 value ≥ 4.08 ng/mL (upper tertile) (log-rank test χ2 = 9.0; p = 0.003). Multivariate Cox regression analysis showed a peak post-PCI PTX3 value ≥ 4.08 ng/mL as an independent predictor of MACE (hazard ratio, 3.915; 95% CI, 1.129-13.583; p = 0.03). CONCLUSIONS: Peak post-PCI PTX3 values correlated with pre-PCI plaque characteristics and post-PCI outcomes, providing a good prognostic factor of outcomes in SAP patients undergoing elective PCI.

12.
Catheter Cardiovasc Interv ; 95(1): E8-E16, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30983087

RESUMO

OBJECTIVE: The aim of this study was to compare how prasugrel and clopidogrel affect platelet aggregation reactivity, cardiac enzyme release, cardiac remodeling, and the formation of in-stent thrombi after primary percutaneous coronary intervention (PCI). BACKGROUND: The advantages of using prasugrel over clopidogrel in cardiac injury following acute coronary syndrome (ACS) remain unclear. METHODS: A total of 78 ACS patients were randomly allocated into clopidogrel (300 mg loading/75 mg maintenance) or prasugrel (20 mg loading/3.75 mg maintenance) treatment groups, followed by undergoing primary PCI. Platelet reactivity and cardiac enzymes were measured before and after primary PCI. Moreover, cardiac function was measured by ultrasound echocardiography and coronary angioscopic observation was after primary PCI up to 8 months later. RESULTS: Antiplatelet reactivity in the prasugrel treatment group reached optimal levels (P2Y12 reaction units [PRU] less than 262) immediately after the administration and was maintained even at 8 months, independently of the CYP2C19 genotype. Prasugrel treatment significantly suppressed creatine kinase elevation compared to clopidogrel treatment (median value 404 IU/L to 726 IU/L vs. 189 IU/L to 1,736 IU/L, p = 0.018 for maximum values) and reduced left ventricular mass (217.2-168.8 g in prasugrel, p = 0.045; 196.9-176.4 g in clopidogrel, p = 0.061). There were no significant differences in the incidence of in-stent attached thrombi between the two groups. CONCLUSIONS: Compared to clopidogrel, prasugrel produced a stable platelet aggregation inhibitory effect in patients with ACS regardless of CYP2C19 genotype, reduced cardiac enzyme release, and prevented cardiac remodeling after ACS.


Assuntos
Síndrome Coronariana Aguda/terapia , Clopidogrel/administração & dosagem , Trombose Coronária/prevenção & controle , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Inibidores da Agregação de Plaquetas/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Cloridrato de Prasugrel/administração & dosagem , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/fisiopatologia , Idoso , Clopidogrel/efeitos adversos , Clopidogrel/sangue , Trombose Coronária/diagnóstico por imagem , Trombose Coronária/etiologia , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Variantes Farmacogenômicos , Inibidores da Agregação de Plaquetas/efeitos adversos , Inibidores da Agregação de Plaquetas/sangue , Cloridrato de Prasugrel/efeitos adversos , Cloridrato de Prasugrel/sangue , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/sangue , Fatores de Risco , Fatores de Tempo , Tóquio , Resultado do Tratamento
13.
Int J Cardiovasc Imaging ; 35(12): 2147-2155, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31359232

RESUMO

Tortuous coronary lesions are associated with adverse outcomes after implantation of bare metal or first-generation drug-eluting stents (DESs). We investigated the impact of lesion angle on vessel wall injuries and stent apposition as assessed by optical coherence tomography (OCT) after second- and newer-generation DES implantation. We investigated 95 de novo lesions treated with a single DES (62 platinum-chromium everolimus-eluting stents and 33 bioresorbable-polymer sirolimus-eluting stents). Post-intervention OCT findings were compared between angled lesions (≥ 45°; n = 33) and non-angled lesions (< 45°; n = 62). The 12-month clinical outcomes were also compared between the groups. Cross-sectional OCT analysis revealed that compared to non-angled lesions, angled ones had a significantly higher incidence of intra-stent dissection around the centre of the angle (19.7% vs. 10.8%, p = 0.01) and incomplete stent apposition (ISA) in the distal and proximal sub-segments (10.0% vs. 4.1%, p = 0.002; 15.3% vs. 7.9%, p < 0.001, respectively). Strut-based analysis also showed that angled lesions demonstrated a higher rate of malapposed strut in the distal and proximal sub-segments (3.0% vs. 0.9%, p < 0.001; 4.3% vs. 1.8%, p < 0.001, respectively). The 12 month clinical outcomes were comparable between the groups. Compared to non-angled lesions, angled coronary lesions were associated with a higher incidence of intra-stent dissection and ISA on post-intervention OCT after implantation of second- and newer-generation DESs.


Assuntos
Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Tomografia de Coerência Óptica , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/mortalidade , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Valor Preditivo dos Testes , Desenho de Prótese , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
14.
Heart Vessels ; 34(12): 1925-1935, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31203393

RESUMO

Drug-coated balloon angioplasty (DCBA) has been recognized for its utility in preventing in-stent re-restenosis (ISR); however, imaging of the neointima immediately after treatment and during follow-up has only been described in a few case reports. This study aimed to determine the efficacy and mechanism of the DCBA using imaging studies both immediately after the DCBA and during the follow-up period. We enrolled 15 consecutive patients who underwent DCBA for in-stent restenosis (ISR). The in-stent neointimal volume was evaluated using optical coherence tomography (OCT), and the in-stent yellow grade was assessed using coronary angioscopy (CAS) immediately after DCBA and during the median follow-up period of 9 (8-15) months. The neointimal volume was significantly reduced from 77.1 ± 36.2 mm3 at baseline to 60.2 ± 23.9 mm3 immediately after DCBA (p = 0.0012 vs. baseline) and to 46.7 ± 21.9 mm3 during the follow-up (p = 0.0002 vs. post DCBA). The yellow grade of the residual plaques at the ISR lesion, which indicated plaque vulnerability, was significantly decreased in the follow-up CAG (from baseline: 1.79 ± 1.03, during the follow-up: 0.76 ± 0.82; p < 0.0001). These data suggest that DCBA may inhibit neointimal formation and provide angioscopic intimal stabilization for ISR lesions.


Assuntos
Angioplastia Coronária com Balão/métodos , Angioscopia/métodos , Reestenose Coronária/diagnóstico , Vasos Coronários/diagnóstico por imagem , Stents Farmacológicos/efeitos adversos , Oclusão de Enxerto Vascular/diagnóstico , Tomografia de Coerência Óptica/métodos , Idoso , Materiais Revestidos Biocompatíveis , Angiografia Coronária , Reestenose Coronária/cirurgia , Vasos Coronários/cirurgia , Feminino , Seguimentos , Oclusão de Enxerto Vascular/cirurgia , Humanos , Masculino , Neointima/patologia , Reoperação , Estudos Retrospectivos
15.
Respir Investig ; 57(4): 368-375, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31092319

RESUMO

BACKGROUND: Physical activity measures are valuable for assessing the progression of chronic respiratory diseases. The 4-m gait speed (4MGS) test is an established functional assessment in the elderly. However, the relationship between the 4MGS and daily activity in patients with chronic respiratory diseases has not been fully understood. The present study aimed to investigate whether the 4MGS predicted daily activity, including physical activity level (PAL), in patients with chronic respiratory diseases. METHODS: We enrolled 57 patients with chronic respiratory diseases, including interstitial lung disease and chronic obstructive pulmonary disease, and evaluated the correlations between the 4MGS and various clinical parameters, including respiratory function, the 6-min walk test (6MWT), and daily activities, by using an accelerometer. Linear regression analysis was performed to identify significant predictors of daily activity. RESULTS: The 4MGS was significantly correlated with daily step counts and PAL, as well as the 6 min walk distance (r = 0.477, p < 0.001; r = 0.433, p = 0.001; and r = 0.593, p < 0.001, respectively). In the multivariate linear regression analysis, the 4MGS, % predicted forced expiratory volume in 1 s, and body mass index were independent predictors of PAL. Receiver operating characteristic analysis revealed that a 4MGS <1.07 m/s was the optimal cutoff for predicting an inactive PAL (area under the curve, 0.728; 95% confidence interval, 0.589-0.866). Patients with a slower 4MGS had significantly reduced daily activity than did those with a preserved 4MGS, despite similar modified Medical Research Council dyspnea scale measures and respiratory parameters, such as oxygenation profiles. CONCLUSIONS: The 4MGS test is a simple screening test and a useful predictor of worsening daily activity in patients with chronic respiratory diseases.


Assuntos
Atividades Cotidianas , Exercício Físico/fisiologia , Transtornos Respiratórios/fisiopatologia , Velocidade de Caminhada/fisiologia , Acelerometria , Idoso , Índice de Massa Corporal , Doença Crônica , Progressão da Doença , Feminino , Humanos , Modelos Lineares , Doenças Pulmonares Intersticiais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Curva ROC
16.
Heart Vessels ; 34(9): 1429-1439, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30976923

RESUMO

Low wall shear stress (WSS) is associated with plaque formation. However, the relationship between WSS and coronary plaque vulnerability remains unclear. Therefore, this study aimed to clarify the in vivo relationship between luminal WSS derived from three-dimensional (3D) computed tomography (CT) and plaque vulnerability within the coronary artery. Forty-three consecutive patients with ischemic heart disease and coronary stenotic lesions were enrolled and underwent coronary angiography and color-coded intravascular ultrasonography (iMap™) followed by multi-slice coronary CT angiography. CT-derived high-risk plaque was defined by specific CT characteristics, including low CT intensity (< 30 HU) and positive remodeling. The Student's t test, Mann-Whitney U test, χ2 test, repeated measures analysis of variance, and logistic and multiple regression were used for statistical analyses. CT-derived high-risk plaque (n = 15) had higher values of maximum and average shear stress than CT-derived stable plaque (474 ± 453 vs. 158 ± 138 Pa, p = 0.018; 4.2 ± 3.1 vs. 1.6 ± 1.2 Pa, p = 0.007, respectively). Compared with patients with CT-derived stable plaque, those with CT-derived high-risk plaque had a higher prevalence of necrotic and lipidic characteristics (44 ± 13 vs. 31 ± 11%, p = 0.001) based on iMap™. Multivariate logistic regression analysis showed that the average WSS and necrotic plus lipidic content were independent determinants of CT-derived high-risk plaque (average WSS: odds ratio 2.996, p = 0.014; necrotic plus lipidic content: odds ratio 1.306, p = 0.036). Our findings suggested that CT-derived high-risk plaque may coexist with high shear stress on the plaque surface.


Assuntos
Estenose Coronária/patologia , Vasos Coronários/patologia , Isquemia Miocárdica/patologia , Placa Aterosclerótica/patologia , Estresse Mecânico , Idoso , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Isquemia Miocárdica/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Estudos Retrospectivos , Ultrassonografia de Intervenção
17.
Exp Anim ; 68(3): 361-370, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30996149

RESUMO

In Japan, it is possible to generate chimeric animals from specified embryos by combining animal blastocysts with human pluripotent stem (PS) cells (animal-human PS chimera). However, the production of animal-human PS chimeras has been restricted because of ethical concerns, such as the development of human-like intelligence and formation of humanized gametes in the animals, owing to the contributions of human PS cells to the brain and reproductive organs. To solve these problems, we established a novel blastocyst complementation technology that does not contribute to the gametes or the brain. First, we established GFP-expressing mouse embryonic stem cells (G-mESCs) in which the Prdm14 and Otx2 genes were knocked out and generated chimeric mice by injecting them into PDX-1-deficient blastocysts. The results showed that the G-mESCs did not contribute to the formation of gametes and the brain. Therefore, in the PDX-1-deficient mice complemented by G-mESCs without the Prdm14 and Otx2 genes, the germline was not transmitted to the next generations. This approach could address concerns regarding the development of both human gametes and a human-like brain upon mouse blastocyst complementation using human stem cells.


Assuntos
Blastocisto/citologia , Diferenciação Celular/fisiologia , Técnicas de Cultura Embrionária/métodos , Transferência Embrionária/métodos , Células-Tronco Embrionárias Murinas/citologia , Animais , Encéfalo/fisiologia , Feminino , Células Germinativas/fisiologia , Japão , Masculino , Camundongos , Camundongos Endogâmicos ICR
18.
J Atheroscler Thromb ; 26(11): 997-1006, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30918164

RESUMO

AIM: Knowledge of subclinical plaque morphology and plaque distribution in the aorta in vivo remains unclear. This study aimed to increase the body of knowledge in this area. METHODS: We enrolled 37 consecutive patients with stable angina pectoris patients who underwent non-obstructive angioscopy for both the coronary artery and aorta immediately after percutaneous coronary intervention. We evaluated the presence of aortic plaques and the distribution of plaque instability. Patients were allocated into two groups according to the number of vulnerable plaques in whole aorta (a low [0-11] and high [≥ 12] group). We evaluated the relationships between the two groups in terms of cardiovascular risk factors. RESULTS: Aortic plaques were identified using non-obstructive angioscopy in all patients, and the greatest number of plaques was found at the infrarenal abdominal aorta (IAA) (the aortic arch, the descending thoracic aorta, the suprarenal abdominal aorta, the IAA, and common iliac artery; 65%, 76%, 65%, 95%, and 49%, respectively; p<0.001). The maximum yellow grade, and the number of intense yellow plaques, ruptured plaques, and thrombi were highest at the IAA (p<0.001). The prevalence of diabetes mellitus and peripheral arterial disease was higher in the high vulnerable plaque group (83.3% vs. 40.0%, p=0.010, 50.0% vs. 8.0%, p=0.005, respectively). CONCLUSIONS: Aortic atherosclerosis was the most severe at the IAA, and aortic plaque vulnerability and distribution were associated with the prevalence of diabetes mellitus and peripheral artery disease in patients with stable angina pectoris. Non-obstructive angioscopy may identify patients at high risk of future aortic events.


Assuntos
Angioscopia/métodos , Aorta/patologia , Aterosclerose/etiologia , Aterosclerose/patologia , Placa Aterosclerótica/fisiopatologia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Fatores de Risco
19.
Phys Chem Chem Phys ; 21(11): 5966-5973, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30839041

RESUMO

Band alignment between two materials is of fundamental importance for a multitude of applications. However, density functional theory (DFT) either underestimates the bandgap - as is the case with the local density approximation (LDA) or generalized gradient approximation (GGA) - or is highly computationally demanding, as is the case with hybrid-functional methods. The latter can become prohibitive in electronic-structure calculations of supercells which describe quantum wells. We propose to apply the DFT+U method, with U for each atomic shell being treated as set of tuning parameters, to automatically fit the bulk bandgap and the lattice constant, and then use the thus obtained U parameters in large supercell calculations to determine the band alignment. We apply this procedure to InP/In0.5Ga0.5As, In0.5Ga0.5As/In0.5Al0.5As and InP/In0.5Al0.5As quantum wells, and obtain good agreement with experimental results. Although this procedure requires some experimental input, it provides both meaningful valence and conduction band offsets while, crucially, lattice relaxation is taken into account. The computational cost of this procedure is comparable to that of LDA. We believe that this is a practical procedure that can be useful for providing accurate estimates of band alignments between more complicated alloys.

20.
Sci Rep ; 9(1): 1368, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718661

RESUMO

Predicting physical response of an artificially structured material is of particular interest for scientific and engineering applications. Here we use deep learning to predict optical response of artificially engineered nanophotonic devices. In addition to predicting forward approximation of transmission response for any given topology, this approach allows us to inversely approximate designs for a targeted optical response. Our Deep Neural Network (DNN) could design compact (2.6 × 2.6 µm2) silicon-on-insulator (SOI)-based 1 × 2 power splitters with various target splitting ratios in a fraction of a second. This model is trained to minimize the reflection (to smaller than ~ -20 dB) while achieving maximum transmission efficiency above 90% and target splitting specifications. This approach paves the way for rapid design of integrated photonic components relying on complex nanostructures.

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