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1.
Opt Express ; 31(8): 12433-12448, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157403

RESUMO

Cavity optomechanics with picometer displacement measurement resolution has shown vital applications in high-precision sensing areas. In this paper, an optomechanical micro hemispherical shell resonator gyroscope (MHSRG) is proposed, for the first time. The MHSRG is driven by the strong opto-mechanical coupling effect based on the established whispering gallery mode (WGM). And the angular rate is characterized by measuring the transmission amplitude changing of laser coupled in and out from the optomechanical MHSRG based on the dispersive resonance wavelength shift and/or dissipative losses varying. The detailed operating principle of high-precision angular rate detection is theoretically explored and the fully characteristic parameters are numerically investigated. Simulation results show that the optomechanical MHSRG can achieve scale factor of 414.8 mV/ (°/ s) and angular random walk of 0.0555 °/ h1/2 when the input laser power is 3 mW and resonator mass is just 98 ng. Such proposed optomechanical MHSRG can be widely used for chip-scale inertial navigation, attitude measurement, and stabilization.

2.
Molecules ; 27(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144656

RESUMO

In this work, a three-component reaction of 3-acetyl-4-hydroxycoumarine, malononitrile, or cyanoacetate in the presence of ammonium acetate was used to form coumarin derivatives. The chemical structures of new compounds were identified by 1H, 13C NMR and an elemental analysis. These compounds were examined in vitro for their antimicrobial activity against a panel of bacterial strains. In addition, these compounds were investigated for antioxidant activities by superoxideradical, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and hydroxyl radical scavenging assays, in which most of them displayed significant antioxidant activities. Furthermore, these compounds were evaluated for anti-inflammatory activity by indirect hemolytic and lipoxygenase inhibition assays and revealed good activity. In addition, screening of the selected compounds 2-4 against colon carcinoma cell lines (HCT-116) and hepatocellular carcinoma cell lines (HepG-2) showed that that 2-amino-4-hydroxy-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)nicotinonitrile 4 exhibited good cytotoxic activity against standard Vinblastine, while the other compounds exhibited moderate cytotoxic activity. Docking simulation showed that2-amino-4-hydroxy-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)nicotinonitrile 4 is an effective inhibitor of the tumor protein HCT-116. A large fluorescence enhancement in a highly acidic medium was observed, and large fluorescence quenching by the addition of traces of Cu2+ and Ni2+ was also remarked.


Assuntos
Anti-Infecciosos , Antineoplásicos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cumarínicos/química , Cumarínicos/farmacologia , Radical Hidroxila , Lipoxigenases , Simulação de Acoplamento Molecular , Vimblastina
3.
Basic Res Cardiol ; 117(1): 23, 2022 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-35460434

RESUMO

Late, repetitive or chronic remote ischaemic conditioning (CRIC) is a potential cardioprotective strategy against adverse remodelling following ST-segment elevation myocardial infarction (STEMI). In the randomised Daily Remote Ischaemic Conditioning Following Acute Myocardial Infarction (DREAM) trial, CRIC following primary percutaneous coronary intervention (P-PCI) did not improve global left ventricular (LV) systolic function. A post-hoc analysis was performed to determine whether CRIC improved regional strain. All 73 patients completing the original trial were studied (38 receiving 4 weeks' daily CRIC, 35 controls receiving sham conditioning). Patients underwent cardiovascular magnetic resonance at baseline (5-7 days post-STEMI) and after 4 months, with assessment of LV systolic function, infarct size and strain (longitudinal/circumferential, in infarct-related and remote territories). At both timepoints, there were no significant between-group differences in global indices (LV ejection fraction, infarct size, longitudinal/circumferential strain). However, regional analysis revealed a significant improvement in longitudinal strain in the infarcted segments of the CRIC group (from - 16.2 ± 5.2 at baseline to - 18.7 ± 6.3 at follow up, p = 0.0006) but not in corresponding segments of the control group (from - 15.5 ± 4.0 to - 15.2 ± 4.7, p = 0.81; for change: - 2.5 ± 3.6 versus + 0.3 ± 5.6, respectively, p = 0.027). In remote territories, there was a lower increment in subendocardial circumferential strain in the CRIC group than in controls (- 1.2 ± 4.4 versus - 2.5 ± 4.0, p = 0.038). In summary, CRIC following P-PCI for STEMI is associated with improved longitudinal strain in infarct-related segments, and an attenuated increase in circumferential strain in remote segments. Further work is needed to establish whether these changes may translate into a reduced incidence of adverse remodelling and clinical events. Clinical Trial Registration: http://clinicaltrials.gov/show/NCT01664611 .


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda
4.
Clin Spine Surg ; 35(6): 264-269, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35180720

RESUMO

STUDY DESIGN: Retrospective Database Study. OBJECTIVE: Investigate utilization of bone morphogenetic protein (BMP-2) between 2004 and 2014. SUMMARY OF BACKGROUND DATA: The utilization, particularly off-label utilization, of BMP-2 has been controversial and debated in the literature. Given the concerns regarding cancer and potential complications, the risk benefit profile of BMP must be weighed with each surgical case. The debate regarding the costs and potential side effects of BMP-2 compared with autologous iliac crest bone harvest has continued. METHODS: The National Inpatient Sample (NIS) database was queried for the use of BMP-2 (ICD-9-CM 84.52) between 2004 and 2014 across 44 states. The NIS database represents a 20% sample of discharges, weighted to provide national estimates. BMP-2 utilization rates in spine surgery fusion procedures were calculated as a fraction of the total number of thoracic, lumbar, and sacral spinal fusion surgeries performed each year. RESULTS: Between 2004 and 2014, BMP-2 was utilized in 927,275 spinal fusion surgeries. In 2004, BMP-2 was utilized in 28.3% of all cases (N=48,613). The relative use of BMP-2 in spine fusion surgeries peaked in 2008 at 47.0% (N=112,180). Since then, it has continued to steadily decline with an endpoint of 23.6% of cases in 2014 (N=60,863). CONCLUSIONS: Throughout the United States, the utilization of BMP-2 in thoracolumbar fusion surgeries increased from 28.3% to 47.0% between 2004 and 2008. However, from 2008 to 2014, the utilization of BMP-2 in thoracolumbar spine fusion surgeries decreased significantly from 47.0% to 23.4%. While this study provides information on the utilization of BMP-2 for the entire United States over an 11-year period, further research is needed to the determine the factors affecting these trends.


Assuntos
Proteína Morfogenética Óssea 2 , Fusão Vertebral , Proteína Morfogenética Óssea 2/uso terapêutico , Humanos , Região Lombossacral , Estudos Retrospectivos , Fusão Vertebral/métodos , Estados Unidos
5.
JACC Cardiovasc Imaging ; 15(6): 1001-1011, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35033490

RESUMO

BACKGROUND: The pathophysiological and clinical significance of microvascular dysfunction (MVD) in patients with heart failure with preserved ejection fraction (HFpEF) remains uncertain. OBJECTIVES: The aim of this study was to use cardiovascular magnetic resonance to: 1) quantify coronary microvascular function; 2) examine the relationship between perfusion and fibrosis; and 3) evaluate the impact of MVD and fibrosis on long-term clinical outcomes. METHODS: In a prospective, observational study, patients with HFpEF and control subjects underwent multiparametric cardiovascular magnetic resonance (comprising assessment of left ventricular volumetry, perfusion, and fibrosis [focal by late gadolinium enhancement and diffuse by extracellular volume]). The primary endpoint was the composite of death or hospitalization with heart failure. RESULTS: One hundred and one patients with HFpEF (mean age 73 ± 9 years, mean ejection fraction 56% ± 5%) and 43 control subjects (mean age 73 ± 5 years, mean ejection fraction 58% ± 5%) were studied. Myocardial perfusion reserve (MPR) was lower in patients with HFpEF versus control subjects (1.74 ± 0.76 vs 2.22 ± 0.76; P = 0.001). MVD (defined as MPR <2.0) was present in 70% of patients with HFpEF (vs 48% of control subjects; P = 0.014). There was no significant linear correlation between MPR and diffuse fibrosis (r = -0.10; P = 0.473) and no difference in MPR between those with and without focal fibrosis (mean difference -0.03; 95% CI: -0.37 to 0.30). In the HFpEF group, during median follow-up of 3.1 years, there were 45 composite events. MPR was independently predictive of clinical outcome following adjustment for clinical, blood, and imaging parameters (1 SD increase: HR: 0.673 [95% CI: 0.463 to 0.978; P = 0.038]; HR: 0.694 [95% CI: 0.491 to 0.982; P = 0.039]; and HR: 0.690 [95% CI: 0.489 to 0.973; P = 0.034], respectively). CONCLUSIONS: MVD is highly prevalent among patients with HFpEF and is an independent predictor of prognosis. The lack of correlation between MVD and fibrosis may challenge the assertion of a direct causal link between these entities. (Developing Imaging and Plasma Biomarkers in Describing Heart Failure With Preserved Ejection Fraction [DIAMONDHFpEF]; NCT03050593).


Assuntos
Insuficiência Cardíaca , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Fibrose , Gadolínio , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Volume Sistólico , Função Ventricular Esquerda
6.
Results Phys ; 31: 105045, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34840938

RESUMO

The term COVID-19 is an abbreviation of Coronavirus 2019, which is considered a global pandemic that threatens the lives of millions of people. Early detection of the disease offers ample opportunity of recovery and prevention of spreading. This paper proposes a method for classification and early detection of COVID-19 through image processing using X-ray images. A set of procedures are applied, including preprocessing (image noise removal, image thresholding, and morphological operation), Region of Interest (ROI) detection and segmentation, feature extraction, (Local binary pattern (LBP), Histogram of Gradient (HOG), and Haralick texture features) and classification (K-Nearest Neighbor (KNN) and Support Vector Machine (SVM)). The combinations of the feature extraction operators and classifiers results in six models, namely LBP-KNN, HOG-KNN, Haralick-KNN, LBP-SVM, HOG-SVM, and Haralick-SVM. The six models are tested based on test samples of 5,000 images with the percentage of training of 5-folds cross-validation. The evaluation results show high diagnosis accuracy from 89.2% up to 98.66%. The LBP-KNN model outperforms the other models in which it achieves an average accuracy of 98.66%, a sensitivity of 97.76%, specificity of 100%, and precision of 100%. The proposed method for early detection and classification of COVID-19 through image processing using X-ray images is proven to be usable in which it provides an end-to-end structure without the need for manual feature extraction and manual selection methods.

7.
ESC Heart Fail ; 8(3): 2328-2333, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33694306

RESUMO

AIMS: The aim of the study was to assess the association of P-selectin with outcomes in heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS: This is a prospective, observational study of 130 HFpEF patients who underwent clinical profiling, blood sampling, 6 min walk testing, Minnesota Living with Heart Failure Questionnaire evaluation, echocardiography, cardiovascular magnetic resonance imaging, calculation of the Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) risk scores, and blinded plasma P-selectin measurement. Patients were followed up for the endpoint of all-cause mortality. The HFpEF subgroup with higher P-selectin levels [overall median 26 372, inter-quartile range (19 360-34 889) pg/mL] was associated with lower age, higher heart rate, less prevalent atrial fibrillation, more frequent current smoking status, and lower right ventricular end-diastolic volumes. During follow-up (median 1428 days), there were 38 deaths. Following maximal sensitivity and specificity receiver operating characteristic curve analysis, P-selectin levels above 35 506 pg/mL were associated with greater risk of all-cause mortality [hazard ratio (HR) 2.700; 95% confidence interval (CI) 1.416-5.146; log-rank P = 0.002]. Following multivariable Cox proportional hazards regression analysis and when added to MAGGIC scores, only P-selectin (adjusted HR 1.707; 95% CI 1.099-2.650; P < 0.017) and myocardial infarction detected by cardiovascular magnetic resonance imaging (HR 2.377; 95% CI 1.114-5.075; P < 0.025) remained significant predictors. In a final model comprising all three parameters, only P-selectin (HR 1.447; 95% CI 1.130-1.853; P < 0.003) and MAGGIC scores (HR 1.555; 95% CI 1.136-2.129; P < 0.006) remained independent predictors of death. Adding P-selectin (0.618, P = 0.035) improved the area under the receiver operating characteristic curve for mortality prediction for MAGGIC scores (0.647, P = 0.009) to 0.710, P < 0.0001. CONCLUSIONS: Plasma P-selectin is an independent predictor of mortality and provides incremental prognostic information beyond MAGGIC scores in HFpEF.


Assuntos
Insuficiência Cardíaca , Ecocardiografia , Humanos , Metanálise como Assunto , Selectina-P , Estudos Prospectivos , Volume Sistólico
8.
Int J Cardiovasc Imaging ; 37(1): 255-266, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32737707

RESUMO

There is a paucity of data characterizing right ventricular performance in heart failure with preserved ejection fraction (HFpEF) using the gold standard of cardiovascular magnetic resonance imaging (CMR). We aimed to assess the proportion of right ventricular systolic dysfunction (RVD) in HFpEF and the relation to clinical outcomes. As part of a single-centre, prospective, observational study, 183 subjects (135 HFpEF, and 48 age- and sex-matched controls) underwent extensive characterization with CMR. transthoracic echocardiography, blood sampling and six-minute walk testing. Patients were followed for the composite endpoint of death or HF hospitalization. RVD (defined as right ventricular ejection fraction < 47%) controls was present in 19% of HFpEF. Patients with RVD presented more frequently with lower systolic blood pressure, atrial fibrillation, radiographic evidence of pulmonary congestion and raised cardiothoracic ratio and larger right ventricular volumes. During median follow-up of 1429 days, 47% (n = 64) of HFpEF subjects experienced the composite endpoint of death (n = 22) or HF hospitalization (n = 42). RVD was associated with an increased risk of composite events (Log-Rank p = 0.001). In multivariable Cox regression analysis, RVD was an independent predictor of adverse outcomes (adjusted Hazard Ratio [HR] 3.946, 95% CI 1.878-8.290, p = 0.0001) along with indexed extracellular volume (HR 1.742, CI 1.176-2.579, p = 0.006) and E/E' (HR 1.745, CI 1.230-2.477, p = 0.002). RVD as assessed by CMR is prevalent in nearly one-fifth of HFpEF patients and is independently associated with death and/or hospitalization with HF.The trial was registered retrospectively on ClinicalTrials.gov (Identifier: NCT03050593). The date of registration was February 06, 2017.


Assuntos
Insuficiência Cardíaca/epidemiologia , Volume Sistólico , Disfunção Ventricular Direita/epidemiologia , Função Ventricular Direita , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Ecocardiografia , Inglaterra/epidemiologia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/mortalidade , Disfunção Ventricular Direita/fisiopatologia
10.
ESC Heart Fail ; 7(6): 4089-4099, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32935918

RESUMO

AIMS: This study aimed to assess plasma fibroblast growth factor 23 (FGF23) in patients with heart failure with preserved ejection fraction (HFpEF) and its relation to inflammation, renal function, clinical and imaging characteristics, exercise capacity, and prognosis. METHODS AND RESULTS: We performed a prospective, observational study of 172 age-matched and sex-matched subjects (HFpEF n = 130; controls n = 42, age 73 ± 9, female 50%) who underwent plasma biomarker sampling, echocardiography, cardiac magnetic resonance imaging, and 6 min walk testing (6MWT). The primary endpoint was the composite of all-cause death or HF hospitalization. FGF23 was higher in HFpEF compared with controls (62 [42-105] vs. 34 [22-41] pg/mL, P < 0.0001). In HFpEF, FGF23 correlated with greater symptom burden (New York Heart Association class: r = 0.308), poorer exercise capacity (6MWT distance: r = -0.345), and plasma biomarkers reflecting inflammation (highly sensitive C-reactive protein: r = 0.207, myeloperoxidase: r = 0.311), bone metabolism (osteoprotegerin: r = 0.446), renal dysfunction (urea: r = 0.267, creatinine: r = 0.351, estimated glomerular filtration rate: r = -0.367), and echocardiographic E/e' (r = 0.298); P < 0.05. Following multivariable linear regression modelling, FGF23 remained independently associated with shorter 6MWT distance (P = 0.012) in addition to age, body mass index, and lower haemoglobin. During follow-up (median 1428 days), there were 61 composite events (21 deaths, 40 HF hospitalizations) in patients with HFpEF. In multivariable Cox regression analysis, FGF23 [adjusted hazard ratio (HR) 1.665; 95% confidence interval (CI) (1.284-2.160; P < 0.0001)], B-type natriuretic peptide (HR 1.433; CI 1.053-1.951; P = 0.022), and prior HF hospitalization (HR 2.058; CI 1.074-3.942; P = 0.030) were independent predictors of the composite endpoint. CONCLUSIONS: Plasma FGF23 is higher in HFpEF compared with age-matched and sex-matched controls and is strongly associated with exercise incapacity and prognosis. FGF23 correlates with plasma markers of inflammation and renal impairment.

11.
Biomarkers ; 25(7): 556-565, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32803990

RESUMO

INTRODUCTION: Tenascin-C is a marker of interstitial fibrosis. We assessed whether plasma Tenascin-C differed between heart failure with preserved ejection fraction (HFpEF) and asymptomatic controls and related to clinical outcomes. MATERIALS AND METHODS: Prospective, observational study of 172 age- and sex-matched subjects (HFpEF n = 130; controls n = 42, age 73 ± 9, males 50%) who underwent phenotyping with 20 plasma biomarkers, echocardiography, cardiac MRI and 6-minute-walk-testing. The primary endpoint was the composite of all-cause death/HF hospitalisation. RESULTS: Tenascin-C was higher in HFpEF compared to controls (13.7 [10.8-17.3] vs (11.1 [8.9-12.9] ng/ml, p < 0.0001). Tenascin-C correlated positively with markers of clinical severity (NYHA, E/E', BNP) and plasma biomarkers reflecting interstitial fibrosis (ST-2, Galectin-3, GDF-15, TIMP-1, TIMP-4, MMP-2, MMP-3, MMP-7, MMP-8), cardiomyocyte stress (BNP, NTpro-ANP), inflammation (MPO, hs-CRP, TNFR-1, IL6) and renal dysfunction (urea, cystatin-C, NGAL); p < 0.05 for all. During follow-up (median 1428 days), there were 61 composite events (21 deaths, 40 HF hospitalizations). In multivariable Cox regression analysis, Tenascin-C (adjusted hazard ratio [HR] 1.755, 95% confidence interval [CI] 1.305-2.360; p < 0.0001) and indexed extracellular volume (HR 1.465, CI 1.019-2.106; p = 0.039) were independently associated with adverse outcomes. CONCLUSIONS: In HFpEF, plasma Tenascin-C is higher compared to age- and sex-matched controls and a strong predictor of adverse outcomes. Trial registration: ClinicalTrials.gov: NCT03050593.


Assuntos
Biomarcadores/sangue , Insuficiência Cardíaca/sangue , Prognóstico , Tenascina/sangue , Adulto , Idoso , Feminino , Galectina 3/sangue , Fator 15 de Diferenciação de Crescimento/sangue , Insuficiência Cardíaca/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico/genética , Inibidor Tecidual de Metaloproteinase-1/sangue
12.
Ther Adv Endocrinol Metab ; 11: 2042018820927179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523675

RESUMO

BACKGROUND: Type 2 diabetes (T2D) is associated with an increased risk of heart failure (HF) and cardiovascular mortality. A large-scale meta-analysis on HF found that diabetes was more frequent in women than men, and diabetes appeared to have attenuated the otherwise protective effect of female sex on progression of cardiomyopathy. The exact underlying mechanisms for this remain unclear. Here, we aimed to determine the effect of sex on the phenotypic expression of diabetic heart disease in patients with T2D. METHODS: A total of 62 male [mean age 44 ± 8 years, body mass index (BMI) 33 ± 5 kg/m2, mean HBA1c of 7.8 ± 1.8%] and 67 female (44 ± 10 years, BMI 35 ± 6 kg/m2, HBA1c 7.6 ± 1.2%) T2D patients on oral glucose-lowering treatment, and 16 male (48 ± 17 years, BMI 25 ± 3 kg/m2) and 14 female (50 ± 10 years, BMI 25 ± 4 kg/m2) controls were recruited. Left ventricular (LV) volumes, mass, function and deformation, and left atrial (LA) volumes and function were assessed using cardiac magnetic resonance imaging (CMR). RESULTS: Participants in all groups were of similar age, and there were no significant differences in blood pressure (BP), diabetes duration or metabolic profile between the two diabetes groups. Concentric remodeling was present in both sexes (p < 0.0001), with greater degree of concentric hypertrophy in males (12%, p = 0.0015). Biplane LA ejection fraction (LAEF) (p = 0.038), peak systolic circumferential strain (p < 0.0001) and diastolic strain rates (p = 0.001) were significantly reduced in men compared with women with T2D. There were no significant differences in biplane LAEF, peak systolic circumferential strain and diastolic strain rates in women with T2D compared with female controls. Whereas in women with T2D, glycaemic control was linked to LV contractile function, there was no such relationship in men with T2D. CONCLUSION: Male sex adversely affects the phenotypic expression of diabetic heart disease. The striking differences in the cardiac phenotype between male and female patients with T2D promote awareness of gender-specific risk factors in search of treatment and prevention of diabetes-associated HF. CONDENSED ABSTRACT: We aimed to determine the effect of sex on the phenotypic expression of diabetic heart disease in patients with T2D. While our findings support the notion that in T2D, male sex adversely affects the phenotypic expression of diabetic heart disease, this is in apparent conflict with the previous large-scale study showing diabetes attenuates the otherwise protective effect of female sex on progression of cardiomyopathy. Further longitudinal studies looking at gender differences in clinical outcomes in T2D patients are needed. These sex-related differences promote awareness of sex-specific risk factors in search of treatment and prevention of diabetes-associated HF.

13.
PLoS One ; 15(4): e0232280, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32349122

RESUMO

INTRODUCTION: The pathophysiology of heart failure with preserved ejection fraction (HFpEF) remains incompletely defined. We aimed to characterize HFpEF compared to heart failure with reduced ejection fraction (HFrEF) and asymptomatic hypertensive or non-hypertensive controls. MATERIALS AND METHODS: Prospective, observational study of 234 subjects (HFpEF n = 140; HFrEF n = 46, controls n = 48, age 73±8, males 49%) who underwent echocardiography, cardiovascular magnetic resonance imaging (CMR), plasma biomarker analysis (panel of 22) and 6-minute walk testing (6MWT). The primary end-point was the composite of all-cause mortality and/or HF hospitalization. RESULTS: Compared to controls both HF groups had lower exercise capacity, lower left ventricular (LV) EF, higher LV filling pressures (E/E', B-type natriuretic peptide [BNP], left atrial [LA] volumes), more right ventricular (RV) systolic dysfunction, more focal and diffuse fibrosis and higher levels of all plasma markers. LV remodeling (mass/volume) was different between HFpEF (concentric, 0.68±0.16) and HFrEF (eccentric, 0.47±0.15); p<0.0001. Compared to controls, HFpEF was characterized by (mild) reductions in LVEF, more myocardial fibrosis, LA remodeling/dysfunction and RV dysfunction. HFrEF patients had lower LVEF, increased LV volumes, greater burden of focal and diffuse fibrosis, more RV remodeling, lower LAEF and higher LA volumes compared to HFpEF. Inflammatory/fibrotic/renal dysfunction plasma markers were similarly elevated in both HF groups but markers of cardiomyocyte stretch/damage (BNP, pro-BNP, N-terminal pro-atrial natriuretic peptide and troponin-I) were higher in HFrEF compared to HFpEF; p<0.0001. Focal fibrosis was associated with galectin3, GDF-15, MMP-3, MMP-7, MMP-8, BNP, pro-BNP and NTproANP; p<0.05. Diffuse fibrosis was associated with GDF-15, Tenascin-C, MMP-2, MMP-3, MMP-7, BNP, proBNP and NTproANP; p<0.05. Composite event rates (median 1446 days follow-up) did not differ between HFpEF and HFrEF (Log-Rank p = 0.784). CONCLUSIONS: HFpEF is a distinct pathophysiological entity compared to age- and sex-matched HFrEF and controls. HFpEF and HFrEF are associated with similar adverse outcomes. Inflammation is common in both HF phenotypes but cardiomyocyte stretch/stress is greater in HFrEF.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos de Coortes , Ecocardiografia , Teste de Esforço , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Peptídeos Natriuréticos/sangue , Estudos Prospectivos , Volume Sistólico/fisiologia , Remodelação Ventricular
14.
Int J Cardiovasc Imaging ; 36(6): 1133-1146, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32152811

RESUMO

Strain assessment allows accurate evaluation of myocardial function and mechanics in ST-segment elevation myocardial infarction (STEMI). Strain using cardiovascular magnetic resonance (CMR) has traditionally been assessed with tagging but limitations of this technique have led to more widespread use of alternative methods, which may be more robust. We compared the inter-study repeatability of circumferential global peak-systolic strain (Ecc) and peak-early diastolic strain rate (PEDSR) derived by tagging with values obtained using novel cine-based software: Feature Tracking (FT) (TomTec, Germany) and Tissue Tracking (TT) (Circle cvi42, Canada) in patients following STEMI. Twenty male patients (mean age 56 ± 10 years, mean infarct size 13.7 ± 7.1% of left ventricular mass) were randomised to undergo CMR 1-5 days post-STEMI at 1.5 T or 3.0 T, repeated after ten minutes at the same field strength. Ecc and PEDSR were assessed using tagging, FT and TT. Inter-study repeatability was evaluated using Bland-Altman analyses, coefficients of variation (CoV) and intra-class correlation coefficient (ICC). Ecc (%) was significantly lower with tagging than with FT or TT at 1.5 T (- 9.5 ± 3.3 vs. - 17.5 ± 3.8 vs. -15.5 ± 5.2, respectively, p < 0.001) and 3.0 T (- 13.1 ± 1.8 vs. - 19.4 ± 2.9 vs. - 17.3 ± 2.1, respectively, p = 0.001). This was similar for PEDSR (.s-1): 1.5 T (0.6 ± 0.2 vs. 1.5 ± 0.4 vs. 1.0 ± 0.4, for tagging, FT and TT respectively, p < 0.001) and 3.0 T (0.6 ± 0.2 vs. 1.5 ± 0.3 vs. 0.9 ± 0.3, respectively, p < 0.001). Inter-study repeatability for Ecc at 1.5 T was good for tagging and excellent for FT and TT: CoV 16.7%, 6.38%, and 8.65%, respectively. Repeatability for Ecc at 3.0 T was good for all three techniques: CoV 14.4%, 11.2%, and 13.0%, respectively. However, repeatability of PEDSR was generally lower than that for Ecc at 1.5 T (CoV 15.1%, 13.1%, and 34.0% for tagging, FT and TT, respectively) and 3.0 T (CoV 23.0%, 18.6%, and 26.2%, respectively). Following STEMI, Ecc and PEDSR are higher when measured with FT and TT than with tagging. Inter-study repeatability of Ecc is good for tagging, excellent for FT and TT at 1.5 T, and good for all three methods at 3.0 T. The repeatability of PEDSR is good to moderate at 1.5 T and moderate at 3.0 T. Cine-based methods to assess Ecc following STEMI may be preferable to tagging.


Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Feminino , Coração/diagnóstico por imagem , Coração/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sístole
15.
Int J Cardiovasc Imaging ; 36(5): 921-928, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32030576

RESUMO

The aim of this study was to assess the agreements of both biplane and short-axis Simpson's (SAX) methods for left atrial ejection fraction (LAEF) calculation utilising cardiovascular magnetic resonance imaging (CMR) in heart failure with preserved ejection fraction (HFpEF) and evaluate their relation to clinical outcomes. One hundred and thirty six subjects (HFpEF n = 97, controls n = 39) underwent CMR, six-minute walk tests and blood sampling in our prospective, observational, single-centre study. Overall, LAEF (%) was lower in HFpEF patients compared to controls (SAX 34 ± 13 vs 47 ± 8, biplane 34 ± 16 vs 51 ± 11; p < 0.0001 for both). Atrial fibrillation (AF) was present in 24% of HFpEF and was associated with higher LA volumes and lower LAEF compared to sinus rhythm (p < 0.0001) with both methods. Biplane LAEF correlated strongly with SAX measurements (overall Pearson's r = 0.851, sinus rhythm r = 0.651, AF r = 0.882; p < 0.0001). Biplane LAEF did not differ significantly compared to SAX LAEF (overall 34 ± 16 vs 34 ± 13%; p = 0.307) except in AF subjects in whom biplane LAEF was lower (mean difference 2 ± 4%, p = 0.013). There were 44 composite events (25 deaths, 19 HF hospitalizations) in HFpEF during median follow-up of 1429 days. LAEF below the median was associated with increased risk of composite endpoints (Log-Rank biplane p < 0.0001; SAX p = 0.009). In multivariable Cox proportional hazards regression analysis, both biplane LAEF (hazard ratio [HR] 0.604; 95% confidence interval [CI] (0.406-0.900); p = 0.013) and SAX LAEF (HR 0.636; CI 0.441-0.918; p = 0.016) remained independent predictors along with indexed extracellular volume. CMR LAEF, derived from either the short-axis or biplane method is lower in HFpEF compared to healthy controls and remains a strong marker of prognosis.


Assuntos
Função do Átrio Esquerdo , Insuficiência Cardíaca/diagnóstico por imagem , Imageamento por Ressonância Magnética , Volume Sistólico , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Estudos de Casos e Controles , Causas de Morte , Inglaterra , Feminino , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Tempo
16.
N Am Spine Soc J ; 2: 100014, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35141584

RESUMO

BACKGROUND: The utilization of the S2 Alar-Iliac (S2AI) screw provides an optimal method of spinopelvic fixation. The free-hand placement of these screws obviates the use of intra-operative fluoroscopy and relies heavily on sacropelvic anatomy; variations of this anatomy could alter the ideal screw trajectory. The S2AI corridor is near several neurovascular structures, thus an accurate trajectory is critical. The reported angles of trajectory vary within the literature and a paucity of data exists on how patient morphometry influences ideal screw trajectory. We sought to examine the relationship between ideal screw trajectory and pelvic parameters. METHODS: The records of 99 consecutive patients with degenerative thoracolumbar pathology were reviewed and pelvic parameters including sacral slope, pelvic tilt, and pelvic incidence were measured with preoperative standing radiographs. Using 3-dimensional computed tomography (CT) reconstructions, an ideal S2AI trajectory was defined and anteroposterior (horizontal) and cephalocaudal (sagittal) angles were recorded. RESULTS: Pelvic tilt was found to have a moderate inverse correlation with cephalocaudal screw trajectory (r=-0.467, p-value=0.006). Pelvic incidence and sacral slope had weaker correlations with cephalocaudal screw angle. In subgroup analysis, patients with high pelvic tilt (>20°) had a significantly lower cephalocaudal screw trajectory (24.9 ± 3.7° versus 29.8 ± 2.8°, p-value=<0.001) compared to those with a normal pelvic tilt (≤20°). CONCLUSIONS: This study found an inverse relationship between pelvic tilt and cephalocaudal S2AI screw trajectory. Therefore, the sagittal angle of insertion becomes increasingly more perpendicular to the floor (less caudally orientated) as pelvic tilt increases in reference to a patient positioned prone on an operating table parallel to the floor. This may bolster safety and efficacy when utilizing the free-hand technique for placement of the S2AI screw as it allows the surgeon to plan a more ideal trajectory by accounting for pelvic parameters.

17.
Int J Cardiovasc Imaging ; 36(1): 101-110, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31401742

RESUMO

The aim of this study was to determine whether left atrial ejection fraction (LAEF) quantified with cardiovascular magnetic resonance (CMR) was different between heart failure with preserved ejection fraction (HFpEF) and controls, and its relation to prognosis. As part of our single-centre, prospective, observational study, 188 subjects (HFpEF n = 140, controls n = 48) underwent phenotyping with contrast-enhanced CMR, transthoracic echocardiography, blood sampling and six-minute walk testing. LAEF was calculated using the biplane method. Atrial fibrillation (AF) was present in 43 (31%) of HFpEF subjects. Overall, LAEF (%) was lower in HFpEF patients inclusive of AF (32 ± 16) or those in sinus rhythm alone (41 ± 12) compared to controls (51 ± 11), p < 0.0001. LAEF correlated inversely with maximal and minimal left atrial volumes indexed (r = - 0.602, r = - 0.762), and plasma N-terminal pro-atrial natriuretic peptide (r = - 0.367); p < 0.0001. During median follow-up (1429 days), there were 67 composite events of all-cause death or hospitalization for heart failure (22 deaths, 45 HF hospitalizations) in HFpEF. Lower LAEF (below median) was associated with an increased risk of composite endpoints (Log-Rank: all p = 0.028; sinus p = 0.036). In multivariable Cox regression analysis, LAEF (adjusted hazard ratio [HR] 0.767, 95% confidence interval [CI] 0.591-0.996; p = 0.047) and indexed extracellular volume (HR 1.422, CI 1.015-1.992; p = 0.041) were the only parameters that remained significant when added to a base prognostic model comprising age, prior HF hospitalization, diastolic blood pressure, lung disease, NYHA, six-minute-walk-test-distance, haemoglobin, creatinine and B-type natriuretic peptide. CMR-derived LAEF is lower in HFpEF compared to healthy controls and is a strong prognostic biomarker.


Assuntos
Função do Átrio Esquerdo , Insuficiência Cardíaca/fisiopatologia , Volume Sistólico , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , Progressão da Doença , Ecocardiografia , Tolerância ao Exercício , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/mortalidade , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos
18.
Braz. dent. sci ; 23(3): 1-7, 2020. tab, graf
Artigo em Inglês | BBO - Odontologia, LILACS | ID: biblio-1116017

RESUMO

Objective: κ-carrageenan is a food stabilizer agent which has an antiproliferative effect, while vitamin D is a prohormone acts on the nuclear receptor and has a cytotoxic against cancer. This study aimed to show the synergistic effect of using topical κ-carrageenan and oral administration of the vitamin D on the 7, 12-dimethylbenz[a] anthracene (DMBA)-induced oral cancer. Material and Methods: fifty four male albino rats were randomly divided into seven groups: Acetonetreated served as control (Group I), vitamin D (5000UI)-treated (Group II), κ-carrageenan (1%)- treated (Group III), DMBA (0.5%)-treated (Group IV), Acetone, κ-carrageenan and DMBA were administered topically on both cheeks and palate, five times weekly for 12 weeks, while the vitamin D was administered orally twice weekly for 12 weeks. Groups V, VI, and VII were animals treated with vitamin D, κ-carrageenan, and both vitamin D and κ-carrageenan for 8 weeks after induction of oral cancer. At the end of the study, blood samples were obtained by cardiac puncture for determination of TNF-α and EGFR. Results: In the groups III and IV, serum EGFR showed significant low levels compared with Group I. In the Group VII, serum EGFR showed a significantly (p=0.014) low level compared with Group IV (614.3±69.7 pg/ml versus 882.4±45.6 pg/ml, respectively). Higher percentages of high levels of TNF-α were observed in the Groups VI and VII, while a lower percentage of EGFR was observed in the Group VI. Conclusion: both κ-carrageenan and vitamin D have antiproliferative effect against DMBAinducing oral cancer by increasing the levels of TNF-α and suppressing the signaling pathway of EGFR. Concomitant using κ-carrageenan and vitamin D reduces the antiproliferative effect of each other.(AU)


Objetivo: κ-carragenina é um agente estabilizador de alimentos que tem efeito um antiproliferativo, enquanto a vitamina D é um pró-hormônio que atua sobre o receptor nuclear e possui efeito citotóxico contra o câncer. Este estudo teve como objetivo mostrar o efeito sinérgico do uso de κ-carragenina tópica e administração oral da vitamina D no câncer de boca induzido por 7, 12-dimetilbenz[a]antraceno (DMBA). Material e Métodos: cinquenta e quatro ratos albinos machos foram divididos aleatoriamente em sete grupos: tratado com acetona como controle (Grupo I), tratado com vitamina D (5000UI) (grupo II), tratado com κ-carragenina (1%) (grupo III), DMBA (0,5%) tratado (Grupo IV), acetona, κ-carragenina e DMBA foram administrados topicamente nas bochechas e no palato, cinco vezes por semana durante 12 semanas, enquanto a vitamina D foi administrada por via oral duas vezes por semana durante 12 semanas. Os grupos V, VI e VII foram animais tratados com vitamina D, κ-carragenina e No final do estudo, foram obtidas amostras de sangue por punção cardíaca para determinação do TNF-α e EGFR. Resultados: Nos grupos III e IV, o EGFR sérico mostrou níveis baixos significativos em comparação com o Grupo I. No grupo VII, o EGFR sérico mostrou um nível significativamente baixo (p = 0,014) em comparação com o Grupo IV (614,3 ± 69,7 pg / ml versus 882,4 ± 45,6 pg / ml, respectivamente). Maiores porcentagens de TNF-α foram observadas nos Grupos VI e VII, enquanto uma menor porcentagem de EGFR foi observada no Grupo VI. Conclusão: Tanto a κ-carragenina quanto a vitamina D têm efeito antiproliferativo contra o câncer de boca induzido por DMBA aumentando os níveis de TNF-α e suprimindo a via de sinalização do EGFR. O uso concomitante de κ-carragenina e a vitamina D reduz o efeito antiproliferativo um do outro (AU)


Assuntos
Animais , Ratos , Vitamina D , Neoplasias Bucais , Fator de Necrose Tumoral alfa , 9,10-Dimetil-1,2-benzantraceno , Receptores ErbB
19.
Cureus ; 11(8): e5539, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31687312

RESUMO

A survey was administered to a random sampling of the American Academy of Orthopaedic Surgeons (AAOS) members to determine the rate at which recently trained orthopedic surgeons switch their first job and to identify factors affecting the job selection process. There were 351 (21%) respondents. Respondents considered practice location (41%), practice type (28%), and family proximity (23%) as most important while research opportunity (54%) and signing bonus (33%) were considered least important in their first job. Half of the respondents (51%) left their first job before the completion of their fifth year; most left for financial reasons (34%) or because the practice was not as advertised (31%). Many (53%) stated they had minimal training in selecting their first job and most (88%) felt inadequately prepared for the business side of orthopedics. Further studies are needed to evaluate the high rate of initial post-training job attrition to decrease the personal and societal costs of this phenomenon.

20.
Chemistry ; 25(68): 15656-15661, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31544988

RESUMO

The binary lead fluoride Pb3 F8 was synthesized by the reaction of anhydrous HF with Pb3 O4 or by the reaction of BrF3 with PbF2 . The compound was characterized by single-crystal and powder X-ray diffraction, IR, Raman, and solid-state MAS 19 F NMR spectroscopy, as well as thermogravimetric analysis, XP and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Solid-state quantum-chemical calculations are provided for the vibrational analyses and band assignments. The electronic band structure offers an inside view of the mixed valence compound.

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