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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.
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
3.
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
4.
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
5.
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.

6.
J Shoulder Elbow Surg ; 28(3): 407-414, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30771825

RESUMO

BACKGROUND: There is no current consensus on subscapularis mobilization during total shoulder arthroplasty. The purpose of this prospective, randomized controlled trial was to compare functional and radiographic outcomes of the more traditional subscapularis tenotomy (ST) versus lesser tuberosity osteotomy (LTO). METHODS: This study enrolled 60 shoulders in 59 patients with primary osteoarthritis. Thirty shoulders were preoperatively randomized to each group. Preoperative and 6-week, 3-month, 6-month, and 1-year postoperative data were collected. Ultrasound was performed at 3 months to evaluate subscapularis healing in tenotomy subjects, whereas radiographs were used to evaluate osteotomy healing. Intraoperative data included operative time, tenotomy or osteotomy repair time, and osteotomy thickness. RESULTS: No significant differences in range of motion or clinical outcomes occurred at baseline or 1 year postoperatively between the 2 groups. The mean total case duration for ST was significantly less than that for LTO (129.3 minutes vs 152.7 minutes), along with a significantly shorter subscapularis repair time for ST (34.3 minutes vs 39.3 minutes, P = .024). At final follow-up, 27 of 29 LTO shoulders (93.1%) showed bone-to-bone healing on radiographs, whereas 26 of 30 ST shoulders (86.7%) had no full-thickness tear of the subscapularis on ultrasound at 3 months. CONCLUSIONS: Both techniques produced successful objective and subjective clinical outcomes. LTO heals more reliably than ST. Mean total case and subscapularis repair times were significantly greater for LTO than for ST.


Assuntos
Osteoartrite/cirurgia , Articulação do Ombro/cirurgia , Idoso , Artroplastia do Ombro/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico por imagem , Osteoartrite/reabilitação , Osteotomia/métodos , Estudos Prospectivos , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Tenotomia/métodos , Resultado do Tratamento
7.
BMC Cardiovasc Disord ; 17(1): 7, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-28056808

RESUMO

BACKGROUND: To determine if global strain parameters measured by cardiovascular magnetic resonance (CMR) acutely following ST-segment Elevation Myocardial Infarction (STEMI) predict adverse left ventricular (LV) remodelling independent of infarct size (IS). METHODS: Sixty-five patients with acute STEMI (mean age 60 ± 11 years) underwent CMR at 1-3 days post-reperfusion (baseline) and at 4 months. Global peak systolic circumferential strain (GCS), measured by tagging and Feature Tracking (FT), and global peak systolic longitudinal strain (GLS), measured by FT, were calculated at baseline, along with IS. On follow up scans, volumetric analysis was performed to determine the development of adverse remodelling - a composite score based on development of either end-diastolic volume index [EDVI] ≥20% or end-systolic volume index [ESVI] ≥15% at follow-up compared to baseline. RESULTS: The magnitude of GCS was higher when measured using FT (-21.1 ± 6.3%) than with tagging (-12.1 ± 4.3; p < 0.001 for difference). There was good correlation of strain with baseline LVEF (r 0.64-to 0.71) and IS (ρ -0.62 to-0.72). Baseline strain parameters were unable to predict development of adverse LV remodelling. Only baseline IS predicted adverse remodelling - Odds Ratio 1.05 (95% CI 1.01-1.10, p = 0.03), area under the ROC curve 0.70 (95% CI 0.52-0.87, p = 0.04). CONCLUSION: Baseline global strain by CMR does not predict the development of adverse LV remodelling following STEMI.


Assuntos
Imagem Cinética por Ressonância Magnética/métodos , Contração Miocárdica , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Função Ventricular Esquerda , Remodelação Ventricular , Idoso , Área Sob a Curva , Fenômenos Biomecânicos , Distribuição de Qui-Quadrado , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Estresse Mecânico , Fatores de Tempo
8.
Cereb Cortex ; 26(7): 3196-204, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26184647

RESUMO

The "bilingual advantage" theory stipulates that constant selection and suppression between 2 languages results in enhanced executive control (EC). Behavioral studies of EC in bilinguals have employed wide-ranging tasks and report some conflicting results. To avoid concerns about tasks, we employed a different approach, measuring gray matter volume (GMV) in adult bilinguals, reasoning that any EC-associated benefits should manifest as relatively greater frontal GMV. Indeed, Spanish-English-speaking bilinguals exhibited greater bilateral frontal GMV compared with English-speaking monolinguals. Was this observation attributable to the constant selection and inhibition of 2 spoken languages? To answer this question, we drew on bimodal bilinguals of American Sign Language (ASL) and English who, unlike unimodal bilinguals, can simultaneously use both languages and have been shown not to possess the EC advantage. In this group, there was no greater GMV when compared with monolinguals. Together these results provide neuroanatomical evidence in support of the bilingual advantage theory.


Assuntos
Função Executiva , Lobo Frontal/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Modelos Psicológicos , Multilinguismo , Língua de Sinais , Adolescente , Adulto , Feminino , Humanos , Testes de Linguagem , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Adulto Jovem
9.
Eur Heart J ; 37(24): 1910-9, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27147610

RESUMO

BACKGROUND: Microvascular obstruction (MVO) following primary percutaneous coronary intervention (PPCI) treatment of ST-segment elevation myocardial infarction (STEMI) contributes to infarct expansion, left ventricular (LV) remodelling, and worse clinical outcomes. The REFLO-STEMI trial tested whether intra-coronary (IC) high-dose adenosine or sodium nitroprusside (SNP) reduce infarct size and/or MVO determined by cardiac magnetic resonance (CMR). METHODS AND RESULTS: REFLO-STEMI, a prospective, open-label, multi-centre trial with blinded endpoints, randomized (1:1:1) 247 STEMI patients with single vessel disease presenting within 6 h of symptom onset to IC adenosine (2-3 mg total) or SNP (500 µg total) immediately following thrombectomy and again following stenting, or to standard PPCI. The primary endpoint was infarct size % LV mass (%LVM) on CMR undertaken 24-96 h after PPCI (n = 197). Clinical follow-up was to 6 months. There was no significant difference in infarct size (%LVM, median, interquartile range, IQR) between adenosine (10.1, 4.7-16.2), SNP (10.0, 4.2-15.8), and control (8.3, 1.9-14.0), P = 0.062 and P = 0.160, respectively, vs. CONTROL: MVO (% LVM, median, IQR) was similar across groups (1.0, 0.0-3.7, P = 0.205 and 0.6, 0.0-2.4, P = 0.244 for adenosine and SNP, respectively, vs. control 0.3, 0.0-2.8). On per-protocol analysis, infarct size (%LV mass, 12.0 vs. 8.3, P = 0.031), major adverse cardiac events (hazard ratio, HR, 5.39 [1.18-24.60], P = 0.04) at 30 days and 6 months (HR 6.53 [1.46-29.2], P = 0.01) were increased and ejection fraction reduced (42.5 ± 7.2% vs. 45.7 ± 8.0%, P = 0.027) in adenosine-treated patients compared with control. CONCLUSIONS: High-dose IC adenosine and SNP during PPCI did not reduce infarct size or MVO measured by CMR. Furthermore, adenosine may adversely affect mid-term clinical outcome. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01747174; https://clinicaltrials.gov/ct2/show/NCT01747174.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Imageamento por Ressonância Magnética , Estudos Prospectivos , Trombectomia , Resultado do Tratamento
10.
J Cardiovasc Magn Reson ; 18(1): 85, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27842548

RESUMO

BACKGROUND: The CvLPRIT study showed a trend for improved clinical outcomes in the complete revascularisation (CR) group in those treated with an immediate, as opposed to staged in-hospital approach in patients with multivessel coronary disease undergoing primary percutaneous intervention (PPCI). We aimed to assess infarct size and left ventricular function in patients undergoing immediate compared with staged CR for multivessel disease at PPCI. METHODS: The Cardiovascular Magnetic Resonance (CMR) substudy of CvLPRIT was a multicentre, prospective, randomized, open label, blinded endpoint trial in PPCI patients with multivessel disease. These data refer to a post-hoc analysis in 93 patients randomized to the CR arm (63 immediate, 30 staged) who completed a pre-discharge CMR scan (median 2 and 4 days respectively) after PPCI. The decision to stage non-IRA revascularization was at the discretion of the treating interventional cardiologist. RESULTS: Patients treated with a staged approach had more visible thrombus (26/30 vs. 31/62, p = 0.001), higher SYNTAX score in the IRA (9.5, 8-16 vs. 8.0, 5.5-11, p = 0.04) and a greater incidence of no-reflow (23.3 % vs. 1.6 % p < 0.001) than those treated with immediate CR. After adjustment for confounders, staged patients had larger infarct size (19.7 % [11.7-37.6] vs. 11.6 % [6.8-18.2] of LV Mass, p = 0.012) and lower ejection fraction (42.2 ± 10 % vs. 47.4 ± 9 %, p = 0.019) compared with immediate CR. CONCLUSIONS: Of patients randomized to CR in the CMR substudy of CvLPRIT, those in whom the operator chose to stage revascularization had larger infarct size and lower ejection fraction, which persisted after adjusting for important covariates than those who underwent immediate CR. Prospective randomized trials are needed to assess whether immediate CR results in better clinical outcomes than staged CR. TRIAL REGISTRATION: ISRCTN70913605 , Registered 24th February 2011.


Assuntos
Doença da Artéria Coronariana/terapia , Imageamento por Ressonância Magnética , Miocárdio/patologia , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Função Ventricular Esquerda , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Intervenção Coronária Percutânea/efeitos adversos , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Volume Sistólico , Fatores de Tempo , Resultado do Tratamento
11.
J Magn Reson Imaging ; 41(4): 1129-37, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24700404

RESUMO

PURPOSE: To determine the interstudy reproducibility of myocardial strain and peak early-diastolic strain rate (PEDSR) measurement on cardiovascular magnetic resonance imaging (MRI) assessed with feature tracking (FT) and tagging, in patients with aortic stenosis (AS). MATERIALS AND METHODS: Cardiac MRI was performed twice (1-14 days apart) in 18 patients (8 at 1.5 Tesla [T], 10 at 3T) with moderate-severe AS. Circumferential peak systolic strain (PSS) and PEDSR were measured in all patients. Longitudinal PSS and PEDSR were assessed using FT in all patients, and tagging in the 3T sub-group. RESULTS: PSS was higher with FT than tagging (21.0 ± 1.9% versus 17.0 ± 3.4% at 1.5T, 21.4 ± 4.0% versus 17.7 ± 3.0% at 3T, P < 0.05), as was PEDSR (1.3 ± 0.3 s(-1) versus 1.0 ± 0.3 s(-1) , P = 0.10 at 1.5T and 1.3 ± 0.4 s(-1) versus 0.8 ± 0.3 s(-1) , P < 0.05 at 3T). The reproducibility of PSS was excellent with FT (coefficient of variation [CoV] 9-10%) and good with tagging at 1.5T (13-19%). Reproducibility of circumferential PEDSR was best at 1.5T when only basal/mid slices were included (CoV 12%), but moderate to poor at 3T (29-35%). Reproducibility of longitudinal strain was good with FT (10-16%) but moderate for PEDSR (∼30%). CONCLUSION: In patients with AS, FT consistently produces higher values compared with tagging. The interstudy reproducibility of PSS is excellent with FT and good with tagging. The reproducibility of circumferential PEDSR at 1.5T is good when only basal and mid slices are used.


Assuntos
Algoritmos , Estenose da Valva Aórtica/fisiopatologia , Interpretação de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Disfunção Ventricular Esquerda/fisiopatologia , Idoso , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/patologia , Diástole , Módulo de Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resistência ao Cisalhamento , Estresse Mecânico , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia
12.
J Cardiovasc Magn Reson ; 16: 38, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24884638

RESUMO

BACKGROUND: Microvascular obstruction (MVO) describes suboptimal tissue perfusion despite restoration of infarct-related artery flow. There are scarce data on Infarct Size (IS) and MVO in relation to the mode and timing of reperfusion. We sought to characterise the prevalence and extent of microvascular injury and IS using Cardiovascular magnetic resonance (CMR), in relation to the mode of reperfusion following acute ST-Elevation Myocardial Infarction (STEMI). METHODS: CMR infarct characteristics were measured in 94 STEMI patients (age 61.0 ± 13.1 years) at 1.5 T. Seventy-three received reperfusion therapy: primary percutaneous coronary-intervention (PPCI, n = 47); thrombolysis (n = 12); rescue PCI (R-PCI, n = 8), late PCI (n = 6). Twenty-one patients presented late (>12 hours) and did not receive reperfusion therapy. RESULTS: IS was smaller in PPCI (19.8 ± 13.2% of LV mass) and thrombolysis (15.2 ± 10.1%) groups compared to patients in the late PCI (40.0 ± 15.6%) and R-PCI (34.2 ± 18.9%) groups, p <0.001. The prevalence of MVO was similar across all groups and was seen at least as frequently in the non-reperfused group (15/21, [76%] v 33/59, [56%], p = 0.21) and to a similar magnitude (1.3 (0.0-2.8) v 0.4 [0.0-2.9]% LV mass, p = 0.36) compared to patients receiving early reperfusion therapy. In the 73 reperfused patients, time to reperfusion, ischaemia area at risk and TIMI grade post-PCI were the strongest independent predictors of IS and MVO. CONCLUSIONS: In patients with acute STEMI, CMR-measured MVO is not exclusive to reperfusion therapy and is primarily related to ischaemic time. This finding has important implications for clinical trials that use CMR to assess the efficacy of therapies to reduce reperfusion injury in STEMI.


Assuntos
Circulação Coronária , Microcirculação , Infarto do Miocárdio/terapia , Traumatismo por Reperfusão Miocárdica/epidemiologia , Miocárdio/patologia , Intervenção Coronária Percutânea , Terapia Trombolítica , Idoso , Angiografia Coronária , Inglaterra/epidemiologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Intervenção Coronária Percutânea/efeitos adversos , Valor Preditivo dos Testes , Prevalência , Estudos Retrospectivos , Fatores de Risco , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Tempo para o Tratamento , Resultado do Tratamento
13.
Phys Sportsmed ; 40(1): 51-61, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22508251

RESUMO

The elbow is a complex joint consisting of 3 separate but important articulations: the ulnohumeral, radiohumeral, and proximal radioulnar joints. The elbow assists in positioning the hand in space through 2 important motions, flexion-extension and pronation-supination. Although the elbow is not a weightbearing joint, it is subjected to significant loads, especially in overhead and throwing athletes. An accurate knowledge of the anatomy and physiology of the elbow joint is critical for conducting a focused physical examination and arriving at an accurate diagnosis. The goal of this article is to review general and focused physical examination of the elbow in a systematic manner based on medial, lateral, anterior, and posterior aspects.


Assuntos
Articulação do Cotovelo/fisiologia , Cotovelo/fisiologia , Exame Físico/normas , Fenômenos Biomecânicos , Cotovelo/anatomia & histologia , Cotovelo/fisiopatologia , Articulação do Cotovelo/anatomia & histologia , Articulação do Cotovelo/fisiopatologia , Humanos , Artropatias/diagnóstico , Exame Físico/métodos , Amplitude de Movimento Articular , Cotovelo de Tenista/diagnóstico
14.
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
15.
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
16.
Sensors (Basel) ; 11(4): 4401-24, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163854

RESUMO

The new characteristics of Wireless Multimedia Sensor Network (WMSN) and its design issues brought by handling different traffic classes of multimedia content (video streams, audio, and still images) as well as scalar data over the network, make the proposed routing protocols for typical WSNs not directly applicable for WMSNs. Handling real-time multimedia data requires both energy efficiency and QoS assurance in order to ensure efficient utility of different capabilities of sensor resources and correct delivery of collected information. In this paper, we propose a Secure Cluster-based Multipath Routing protocol for WMSNs, SCMR, to satisfy the requirements of delivering different data types and support high data rate multimedia traffic. SCMR exploits the hierarchical structure of powerful cluster heads and the optimized multiple paths to support timeliness and reliable high data rate multimedia communication with minimum energy dissipation. Also, we present a light-weight distributed security mechanism of key management in order to secure the communication between sensor nodes and protect the network against different types of attacks. Performance evaluation from simulation results demonstrates a significant performance improvement comparing with existing protocols (which do not even provide any kind of security feature) in terms of average end-to-end delay, network throughput, packet delivery ratio, and energy consumption.


Assuntos
Redes de Comunicação de Computadores , Segurança Computacional , Multimídia , Tecnologia sem Fio , Algoritmos , Simulação por Computador , Humanos , Armazenamento e Recuperação da Informação
17.
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.

18.
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
19.
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
20.
Sensors (Basel) ; 10(7): 6662-717, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22163571

RESUMO

Wireless Multimedia Sensor Networks (WMSNs) have emerged and shifted the focus from the typical scalar wireless sensor networks to networks with multimedia devices that are capable to retrieve video, audio, images, as well as scalar sensor data. WMSNs are able to deliver multimedia content due to the availability of inexpensive CMOS cameras and microphones coupled with the significant progress in distributed signal processing and multimedia source coding techniques. In this paper, we outline the design challenges of WMSNs, give a comprehensive discussion of the proposed architectures, algorithms and protocols for the different layers of the communication protocol stack for WMSNs, and evaluate the existing WMSN hardware and testbeds. The paper will give the reader a clear view of the state of the art at all aspects of this research area, and shed the light on its main current challenges and future trends. We also hope it will foster discussions and new research ideas among its researchers.


Assuntos
Ondas de Rádio , Telemetria/instrumentação
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