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BACKGROUND: Breast cancer survivors treated with anthracycline-based chemotherapy (AC) have increased risk of functional limitation and cardiac dysfunction. We conducted a 12-month randomized controlled trial in 104 patients with early-stage breast cancer scheduled for AC to determine whether 12 months of exercise training (ExT) could attenuate functional disability (primary end point), improve cardiorespiratory fitness (VO2peak), and prevent cardiac dysfunction. METHODS: Women 40 to 75 years of age with stage I to III breast cancer scheduled for AC were randomized to 3 to 4 days per week aerobic and resistance ExT for 12 months (n=52) or usual care (UC; n=52). Functional measures were performed at baseline, at 4 weeks after AC (4 months), and at 12 months, comprising: (1) cardiopulmonary exercise testing to quantify VO2peak and functional disability (VO2peak ≤18.0 mL·kg-1·min-1); (2) cardiac reserve (response from rest to peak exercise), quantified with exercise cardiac magnetic resonance measures to determine changes in left and right ventricular ejection fraction, cardiac output, and stroke volume; (3) standard-of-care echocardiography-derived resting left ventricular ejection fraction and global longitudinal strain; and (4) biochemistry (troponin and BNP [B-type natriuretic peptide]). RESULTS: Among 104 participants randomized, greater study attrition was observed among UC participants (P=0.031), with 93 women assessed at 4 months (ExT, n=49; UC, n=44) and 87 women assessed at 12 months (ExT, n=49; UC, n=38). ExT attenuated functional disability at 4 months (odds ratio, 0.32 [95% CI, 0.11-0.94]; P=0.03) but not at 12 months (odds ratio, 0.27 [95% CI, 0.06-1.12]; P=0.07). In a per-protocol analysis, functional disability was prevented entirely at 12 months among participants adherent to ExT (ExT, 0% versus UC, 20%; P=0.005). Compared with UC at 12 months, ExT was associated with a net 3.5-mL·kg-1·min-1 improvement in VO2peak that coincided with greater cardiac output, stroke volume, and left and right ventricular ejection fraction reserve (P<0.001 for all). There was no effect of ExT on resting measures of left ventricular function. Postchemotherapy troponin increased less in ExT than in UC (8-fold versus 16-fold increase; P=0.002). There were no changes in BNP in either group. CONCLUSIONS: In women with early-stage breast cancer undergoing AC, 12 months of ExT did not attenuate functional disability, but provided large, clinically meaningful benefits on VO2peak and cardiac reserve. REGISTRATION: URL: https://www.anzctr.org.au/; Unique identifier: ACTRN12617001408370.
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Neoplasias de la Mama , Cardiopatías , Humanos , Femenino , Recién Nacido , Volumen Sistólico , Antraciclinas/efectos adversos , Función Ventricular Izquierda , Unión Europea , Cardiotoxicidad/prevención & control , Cardiotoxicidad/etiología , Reino Unido , Función Ventricular Derecha , Cardiopatías/diagnóstico por imagen , Cardiopatías/prevención & control , Antibióticos Antineoplásicos/farmacología , Ejercicio Físico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , TroponinaRESUMEN
The diagnosis of inflammatory bowel disease (IBD) in children and the need to distinguish between subtypes (Crohn's disease (CD) and ulcerative colitis (UC)) requires lengthy investigative and invasive procedures. Non-invasive, rapid, and cost-effective tests to support these diagnoses are needed. Faecal volatile organic compounds (VOCs) are distinctive in IBD. VOC profiles can be rapidly determined using a gas chromatography-sensor device (OdoReader©). In an inception-cohort of children presenting with suspected IBD, we directly compared the diagnostic fidelity of faecal calprotectin (FCP, a non-specific protein marker of intestinal inflammation) with OdoReader© VOC profiles of children subsequently diagnosed with IBD with matched controls diagnosed with other gastrointestinal conditions. The OdoReader© was 82% (95% confidence interval 75-89%) sensitive and 71% (61-80%) specific but did not outperform FCP (sensitivity 93% (77-99%) and specificity 86% (67-96%); 250 µg/g FCP cut off) in the diagnosis of IBD from other gastrointestinal conditions when validated in a separate sample from the same cohort. However, unlike FCP and better than other similar technologies, the OdoReader© could distinguish paediatric CD from UC (up to 88% (82-93%) sensitivity and 80% (71-89%) specificity in the validation set) and justifies further validation in larger studies. A non-invasive test based on VOCs could help streamline and limit invasive investigations in children.
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Colitis Ulcerosa , Enfermedad de Crohn , Heces , Compuestos Orgánicos Volátiles , Humanos , Colitis Ulcerosa/diagnóstico , Niño , Enfermedad de Crohn/diagnóstico , Compuestos Orgánicos Volátiles/análisis , Masculino , Femenino , Heces/química , Adolescente , Cromatografía de Gases/métodos , Preescolar , Enfermedades Inflamatorias del Intestino/diagnóstico , Diagnóstico Diferencial , Complejo de Antígeno L1 de Leucocito/análisis , Biomarcadores/análisis , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentaciónRESUMEN
BACKGROUND: Acute decompensated heart failure involves a high rate of mortality and complications. Management typically involves a multi-day hospital admission. However, patients often lose part of their function with each successive admission, and are at a high risk for hospital-associated complications such as nosocomial infection. This study aims to determine the safety and efficacy of the management of patients presenting with acute decompensated heart failure to clinic-based therapy vs usual inpatient care using a reproducible management pathway. METHOD: An investigator-initiated, prospective, non-inferiority, 1:1 randomised-controlled trial, stratified by left ventricular ejection fraction including 460 patients with a minimum follow-up of 7 days. This is a multi-centre study to be performed in centres across Victoria, Australia. Participants will be patients with either heart failure with reduced ejection fraction (HFrEF) or heart failure with preserved ejection fraction (HFpEF), admitted for acute decompensation of heart failure. INTERVENTION: Early discharge to an outpatient-based Heart Failure Rapid Access Clinical Review (RACER) in addition to frequent medical/nursing at-home review for patients admitted with decompensated heart failure. RESULTS: The primary endpoint will be a non-inferiority assessment of re-hospitalisation at 30 days. Secondary outcomes include superiority assessment of hospitalisation at 30 days, a composite clinical endpoint of major adverse cardiac and cerebrovascular event (MACCE), hospital re-admission or mortality at 3 months, achievement of guideline-directed medical therapy, patient assessment of symptoms (visual-analogue scale quantified as area under curve and Kansas City Cardiomyopathy Questionnaire-12 [KCCQ-12]), attendance at 3-month outpatient follow-up, number of bed stays/clinics attended, proportion of patients free from congestion, change in serum creatinine level, treatment for electrolyte disturbances, time to transition from intravenous to oral diuretics, and health economics analysis (cost-benefit analysis, cost-utility analysis, incremental cost-effectiveness ratio). CONCLUSIONS: The Early Discharge to Clinic-Based Therapy of Patients Presenting with Decompensated Heart Failure (EDICT-HF) trial will help determine whether earlier discharge to out-of-hospital care is non-inferior to the usual practice of inpatient care, in patients with heart failure admitted to hospital for acute decompensation, as an alternative model of care.
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Insuficiencia Cardíaca , Humanos , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/tratamiento farmacológico , Alta del Paciente , Volumen Sistólico , Estudios Prospectivos , Función Ventricular Izquierda , Victoria/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como AsuntoRESUMEN
INTRODUCTION: The absence of ventricular scar in patients with atrial fibrillation (AF) and systolic heart failure (HF) predicts left ventricular (LV) recovery following AF ablation. It is unknown whether age impacts the degree of LV recovery, reverse remodeling, or AF recurrence following catheter ablation (CA) among this population. OBJECTIVES: To evaluate the impact of age on LV recovery and AF recurrence in a population with AF and systolic HF without fibrosis (termed AF-mediated cardiomyopathy) following CA. METHODS: Consecutive patients undergoing CA between 2013 and 2021 with LV ejection fraction (LVEF) < 45% and absence of cardiac magnetic resonance imaging (CMR) detected LV myocardial fibrosis were stratified by age (<65 vs. ≥65 years). Following CA, participants underwent remote rhythm monitoring for 12 months with repeat CMR for HF surveillance. RESULTS: The study population consisted of 70 patients (10% female, mean LVEF 33 ± 9%), stratified into younger (age < 65 years, 63%) and older (age ≥ 65 years, 37%) cohorts. Baseline comorbidities, LVEF (34 ± 9 vs. 33 ± 8 ≥65 years, p = .686), atrial and ventricular dimensions (left atrial volume index: 55 ± 21 vs. 56 ± 14 mL/m2 age ≥ 65, p = .834; indexed left ventricular end-diastolic volume: 108 ± 40 vs. 104 ± 28 mL/m2 age ≥ 65, p = .681), pharmacotherapy and ablation strategy (pulmonary vein isolation in all; posterior wall isolation in 27% vs. 19% age ≥ 65, p = .448; cavotricuspid isthmus in 9% vs. 11.5% age ≥ 65) were comparable (all p > .05) albeit a higher CHADS2 VASc score in the older cohort (2.7 ± 0.9 vs. 1.6 ± 0.6 age < 65, p < .001). Freedom from AF was comparable (hazard ratio: 0.65, 95% confidence interval: 0.38-1.48, LogRank p = .283) as was AF burden [0% (interquartile range, IQR: 0.0-2.1) vs. age ≥ 65: [0% (IQR 0.0-1.7), p = .516], irrespective of age. There was a significant improvement in LV systolic function in both groups (ΔLVEF + 21 ± 14% vs. +21 ± 12% age ≥ 65, p = .913), with LV recovery in the vast majority (73% vs. 69%, respectively, p = .759) at 13 (IQR: 12-16) months. This was accompanied by comparable improvements in functional status (New York Heart Association class p = .851; 6-min walk distance 50 ± 61 vs. 93 ± 134 m in age ≥ 65, p = .066), biomarkers (ΔN-terminal-pro brain natriuretic peptide -139 ± 246 vs. -168 ± 181 age ≥ 65,p = .629) and HF symptoms (Short Form-36 survey Δphysical component summary p = .483/Δmental component summary, p = .841). CONCLUSION: In patients undergoing CA for AF with systolic HF in the absence of ventricular scar, comparable improvements in ventricular function, symptoms, and freedom from AF are achieved irrespective of age.
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Fibrilación Atrial , Cardiomiopatías , Ablación por Catéter , Insuficiencia Cardíaca Sistólica , Insuficiencia Cardíaca , Humanos , Femenino , Anciano , Masculino , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Fibrilación Atrial/complicaciones , Cicatriz/complicaciones , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/cirugía , Cardiomiopatías/complicaciones , Función Ventricular Izquierda , Miocardio , Volumen Sistólico , Fibrosis , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Resultado del TratamientoRESUMEN
OBJECTIVES: The authors aimed to compare the assessment of left ventricular (LV) stroke volume with transthoracic echocardiography (TTE) using 2- and 3-dimensional (2D and 3D) Doppler and volumetric techniques with gold standard cardiac magnetic resonance imaging (CMR). DESIGN: An observational study. SETTING: A medical research institute. PARTICIPANTS: A total of 187 volunteer participants free of known structural heart disease. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: LV stroke volume was measured with TTE using the following 4 techniques: LV outflow tract (LVOT) pulsed wave Doppler with 2D LVOT area, LVOT pulsed wave Doppler with 3D LVOT area, 2D volumetric (Simpson's biplane), and 3D volumetric techniques. This was compared with gold standard CMR. Stroke volume measured with echocardiography underestimated stroke volume compared to CMR by all techniques (p < 0.001 for all values compared to CMR). The LVOT Doppler stroke volume with a 3D area most closely agreed with CMR, with a bias of 6.35%. This bias progressively increased with 3D volumetric (13.4%), LVOT Doppler with a 2D area (15.1%), and 2D volumetric (18.3%) stroke volume techniques, with wider limits of agreement. CONCLUSION: Of the 4 echocardiographic LV stroke volume measurement methods the authors assessed, stroke volume with LVOT Doppler using 3D measurement of LVOT area most closely approximates gold standard CMR.
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Ecocardiografía Tridimensional , Humanos , Volumen Sistólico , Ecocardiografía Tridimensional/métodos , Ecocardiografía/métodos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: The diagnosis and surveillance of urothelial bladder cancer (UBC) require cystoscopy. There is a need for biomarkers to reduce the frequency of cystoscopy in surveillance; urinary volatile organic compound (VOC) analysis could fulfil this role. This cross-sectional study compared the VOC profiles of patients with and without UBC, to investigate metabolomic signatures as biomarkers. METHODS: Urine samples were collected from haematuria clinic patients undergoing diagnostic cystoscopy and UBC patients undergoing surveillance. Urinary headspace sampling utilised solid-phase microextraction and VOC analysis applied gas chromatography-mass spectrometry; the output underwent metabolomic analysis. RESULTS: The median participant age was 70 years, 66.2% were male. Of the haematuria patients, 21 had a new UBC diagnosis, 125 had no cancer. In the surveillance group, 75 had recurrent UBC, 84 were recurrence-free. A distinctive VOC profile was observed in UBC patients compared with controls. Ten VOCs had statistically significant abundances useful to classify patients (false discovery rate range 1.9 × 10-7-2.8 × 10-2). Two prediction models were evaluated using internal validation. An eight-VOC diagnostic biomarker panel achieved AUROC 0.77 (sensitivity 0.71, specificity 0.72). A six-VOC surveillance biomarker panel obtained AUROC 0.80 (sensitivity 0.71 and specificity 0.80). CONCLUSIONS: Urinary VOC analysis could aid the diagnosis and surveillance of UBC.
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Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Compuestos Orgánicos Volátiles , Anciano , Biomarcadores , Biomarcadores de Tumor/orina , Carcinoma de Células Transicionales/diagnóstico , Carcinoma de Células Transicionales/orina , Estudios Transversales , Femenino , Hematuria , Humanos , Masculino , Recurrencia Local de Neoplasia , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/orina , Compuestos Orgánicos Volátiles/orinaRESUMEN
Cancer therapy related cardiac dysfunction (CTRCD) is an area of increasing focus, particularly during the survivorship period, for paediatric, adolescent and adult cancer survivors. With the advent of immunotherapy and targeted therapy, there is a new set of mechanisms from which paediatric and young adult patients with cancer may suffer cardiovascular injury. Furthermore, cardiovascular disease is the leading cause of morbidity and mortality in the survivorship period. The recently established Australian Cardio-Oncology Registry is the largest and only population-based cardiotoxicity database of paediatric and adolescent and young adult oncology patients in the world, and the first paediatric registry that will document cardiotoxicity caused by chemotherapy and novel targeted therapies using a prospective approach. The database is designed for comprehensive data collection and evaluation of the Australian practice in terms of diagnosis and management of CTRCD. Using the Australian Cardio-Oncology Registry critical clinical information will be collected regarding predisposing factors for the development of CTRCD, the rate of subclinical left ventricular dysfunction and transition to overt heart failure, further research into protectant molecules against cardiac dysfunction and aid in the discovery of which genetic variants predispose to CTRCD. A health economic arm of the study will assess the cost/benefit of both the registry and cardio-oncology clinical implementation. Finally, an imaging arm will establish if exercise cardiac magnetic resonance imaging and VO2 max testing is a more sensitive predictor of cardiac reserve in paediatric and adolescent and young adult oncology patients exposed to cardiac toxic therapies.
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Antineoplásicos , Neoplasias , Adolescente , Antineoplásicos/uso terapéutico , Australia/epidemiología , Cardiotoxicidad/epidemiología , Niño , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/epidemiología , Nueva Zelanda/epidemiología , Sistema de RegistrosRESUMEN
Mass spectrometry (MS) is an analytical technique that can be used for various applications in a number of scientific areas including environmental, security, forensic science, space exploration, agri-food, and numerous others. MS is also continuing to offer new insights into the proteomic and metabolomic fields. MS techniques are frequently used for the analysis of volatile compounds (VCs). The detection of VCs from human samples has the potential to aid in the diagnosis of diseases, in monitoring drug metabolites, and in providing insight into metabolic processes. The broad usage of MS has resulted in numerous variations of the technique being developed over the years, which can be divided into hyphenated and real-time MS techniques. Hyphenated chromatographic techniques coupled with MS offer unparalleled qualitative analysis and high accuracy and sensitivity, even when analysing complex matrices (breath, urine, stool, etc.). However, these benefits are traded for a significantly longer analysis time and a greater need for sample preparation and method development. On the other hand, real-time MS techniques offer highly sensitive quantitative data. Additionally, real-time techniques can provide results in a matter of minutes or even seconds, without altering the sample in any way. However, real-time MS can only offer tentative qualitative data and suffers from molecular weight overlap in complex matrices. This review compares hyphenated and real-time MS methods and provides examples of applications for each technique for the detection of VCs from humans.
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Espectrometría de Masas , Proteómica , Compuestos Orgánicos Volátiles/aislamiento & purificación , Cuerpo Humano , Humanos , Compuestos Orgánicos Volátiles/metabolismoRESUMEN
This study sought to explore the feasibility and utility of post-mortem coronary artery calcium (CAC) scoring in identifying patients with ischemic heart disease as cause of sudden death. 100 deceased patients aged 18-50 years underwent post-mortem examination in the setting of sudden death. At post-mortem, fifty cases were determined to have ischemic heart disease, and fifty had death attributed to trauma or unascertained causes. The CAC score was calculated in a blinded manner from post-mortem CTs performed on all cases. CAC scores were assessable in 97 non-decomposed cases (feasibility 97%). The median CAC score was 88 Agatston units [IQR 0-286] in patients deceased from ischemic heart disease vs 0 [IQR 0-0] in patients deceased from other causes (p < 0.0001). Presence of any coronary calcification differed significantly between ischemic heart disease and non-ischemic groups (adjusted odds ratio 10.7, 95% CI 3.2-35.5). All cases with a CAC score > 100 (n = 22) had ischemic heart disease as the cause of death. Fifteen cases had a CAC score of zero but severe coronary disease at post-mortem examination. Post-mortem CAC scoring is highly feasible. An elevated CAC score in cases 18-50 years old with sudden death predicts ischemic heart disease at post-mortem examination. However, a CAC score of zero does not exclude significant coronary artery disease. Post-mortem CAC score may be considered as a further assessment tool to help predict likely cause of death when there is an objection to or unavailability of post-mortem examination.
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Vasos Coronarios/diagnóstico por imagen , Muerte Súbita/etiología , Isquemia Miocárdica/diagnóstico , Calcificación Vascular/diagnóstico por imagen , Adolescente , Adulto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/mortalidad , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
Urinary volatile compounds (VCs) have been recently assessed for disease diagnoses. They belong to very diverse chemical classes, and they are characterized by different volatilities, polarities and concentrations, complicating their analysis via a single analytical procedure. There remains a need for better, lower-cost methods for VC biomarker discovery. Thus, there is a strong need for alternative methods, enabling the detection of a broader range of VCs. Therefore, the main aim of this study was to optimize a simple and reliable liquid-liquid extraction (LLE) procedure for the analysis of VCs in urine using gas chromatography-mass spectrometry (GC-MS), in order to obtain the maximum number of responses. Extraction parameters such as pH, type of solvent and ionic strength were optimized. Moreover, the same extracts were analyzed using Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR), to evaluate the applicability of a single urine extraction for multiplatform purposes. After the evaluation of experimental conditions, an LLE protocol using 2 mL of urine in the presence of 2 mL of 1 M sulfuric acid and sodium sulphate extracted with dichloromethane was found to be optimal. The optimized method was validated with the external standards and was found to be precise and linear, and allowed for detection of >400 peaks in a single run present in at least 50% of six samples-considerably more than the number of peaks detected by solid-phase microextracton fiber pre-concentration-GC-MS (328 ± 6 vs. 234 ± 4). 1H-NMR spectroscopy of the polar and non-polar extracts extended the range to >40 more (mainly low volatility compounds) metabolites (non-destructively), the majority of which were different from GC-MS. The more peaks detectable, the greater the opportunity of assessing a fingerprint of several compounds to aid biomarker discovery. In summary, we have successfully demonstrated the potential of LLE as a cheap and simple alternative for the analysis of VCs in urine, and for the first time the applicability of a single urine solvent extraction procedure for detecting a wide range of analytes using both GC-MS and 1H-NMR analysis to enhance putative biomarker detection. The proposed method will simplify the transport between laboratories and storage of samples, as compared to intact urine samples.
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Cromatografía de Gases y Espectrometría de Masas/métodos , Extracción Líquido-Líquido/métodos , Extracción Líquido-Líquido/normas , Espectroscopía de Protones por Resonancia Magnética/métodos , Urinálisis/métodos , Compuestos Orgánicos Volátiles/orina , Femenino , HumanosRESUMEN
Neuromorphic computing devices attempt to emulate features of biological nervous systems through mimicking the properties of synapses toward implementing the emergent properties of their counterparts, such as learning. Inspired by recent advances in the utilization of liquid marbles (LMs, microliter quantities of fluid coated in hydrophobic powder) for the creation of unconventional computing devices, we describe the development of LMs with neuromorphic properties through the use of copper coatings and 1.0 mg mL-1 carbon nanotube (CNT)-containing fluid cores. Experimentation was performed through sandwiching the LMs between two cup-style electrodes and stimulating them with repeated dc pulses at 3.0 V. Our results demonstrate that "entrainment" of CNT-filled copper LMs via periodic pulses can cause their electrical resistance to rapidly switch between high to low resistance profiles upon inverting the polarity of stimulation: the reduction in resistance between high and low profiles was approximately 88% after two rounds of entrainment. This effect was found to be reversible through reversion to the original stimulus polarity and was strengthened by repeated experimentation, as evidenced by a mean reduction in time to switching onset of 43%. These effects were not replicated in nanotube solutions not bound inside LMs. Our electrical characterization also reveals that nanotube-filled LMs exhibit pinched loop hysteresis IV profiles consistent with the description of memristors. We conclude by discussing the applications of this technology to the development of unconventional computing devices and the study of emergent characteristics in biological neural tissue.
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Liquid marbles (LMs) have many promising roles in the ongoing development of microfluidics, microreactors, bioreactors, and unconventional computing. In many of these applications, the coalescence of two LMs is either required or actively discouraged, therefore it is important to study liquid marble collisions and establish parameters which enable the desired collision outcome. Recent reports on LM coalescence have focused on either two mobile LMs colliding, or an accelerating LM hitting a sessile LM with a backstop. A further possible scenario is the impact of a mobile LM against a non-supported static LM. This paper investigates such a collision, using high-speed videography for single-frame analysis. Multiple collisions were undertaken whilst varying the modified Weber number (We*) and offset ratios (X*). Parameter ranges of 1.0 < We* < 1.4 and 0.0 < X* < 0.1, resulted in a coalescence rate of approximately 50%. Whereas, parameter ranges X* > 0.25, and We* < 0.95 or We* > 1.55 resulted in 100% non-coalescence. Additionally, observations of LMs moving above a threshold velocity of 0.6 m s-1 have revealed a new and unusual deformation. Comparisons of the outcome of collisions whilst varying both the LM volume and the powder grain size have also been made, revealing a strong link. The results of this work provide a deeper understanding of LM coalescence, allowing improved control when designing future collision experiments.
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Liquid marbles (LMs) have recently attracted interest for use as cargo carriers in digital microfluidics and have successfully been implemented as signal carriers in collision-based unconventional computing circuits. Both application domains require LMs to roll over substantial distances and to survive a certain number of collisions without degrading. To evaluate the lifetime of LMs being subjected to movement and impact stresses, we have selected four types of coating to investigate: polytetrafluoroethylene (PTFE), ultrahigh density polyethylene (PE), Ni, and a mixture of Ni with PE (Ni-PE). Hierarchies of robustness have been constructed which showed that pure PE LMs survived the longest when stationary and in motion. Pure PTFE LMs were shown to be the least resilient to multiple impacts. The PTFE coating provided minimal protection against evaporative losses for small LM volumes (2 and 5 µL) however, larger LMs (10 µL) were shown to have good evaporative stabilities when stationary. Conversely, PE LMs showed a remarkable ability to withstand multiple impacts and were also stable when considering just passive evaporation. Hybrid Ni-PE LMs exhibited more resilience to multiple impacts compared to Ni LMs. Thus, when designing LM devices, it is paramount to determine impact pathways and select appropriate coating materials.
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BACKGROUND: It has long been established that cardiotoxicity occurs as a result of exposure to certain chemotherapeutics, particularly anthracyclines. Historically, clinicians equate cardiotoxicity with a poor prognosis, in a small percentage of patients and deem long-term surveillance as optional. Emerging evidence suggests that anthracycline cardiotoxicity (ACT) is a life-long risk with an incidence approaching 20%. AIMS: To elucidate the incidence of anthracycline cardiotoxicity within a current paediatric oncology survivor cohort. METHODS: Participants were identified through the Haematology-Oncology database at the Royal Children's Hospital, Melbourne. Patients were identified from a retrospective audit of outpatient attendances between January 2008 and December 2015. Patients with a cancer diagnosis exposed to anthracyclines were eligible for the study. Patient demographics and echocardiogram findings were recorded with patients subcategorised according to degree of ACT. More significant ACT defined as fractional shortening (FS) <24% and less significant if FS 24-28% or a decline in baseline ejection fraction of >10%. RESULTS: Two hundred and eighty-six of a total 481 identified patients were eligible for study inclusion. Twenty patients displayed significant ACT with FS <24%. Ten patients had a FS 24-28% and 25 patients with a decline in ejection fraction from baseline of >10%. Overall, 6.6% demonstrated significant cardiac complications, whilst 19.6 % demonstrated some degree of ACT and decline in myocardial function. When stratified for cumulative anthracycline dose, the incidence of severe cardiac dysfunction was 5.1% (<250 mg/m2 ) and 25% (>250 mg/m2 ) CONCLUSION: This study demonstrates, in keeping with modern literature, the higher incidence of anthracycline associated cardiac toxicity and a need for better surveillance and follow up.
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Antineoplásicos/efectos adversos , Cardiotoxinas/efectos adversos , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/diagnóstico por imagen , Médicos/normas , Adolescente , Antraciclinas/efectos adversos , Australia/epidemiología , Cardiotoxicidad/diagnóstico por imagen , Cardiotoxicidad/epidemiología , Enfermedades Cardiovasculares/epidemiología , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Masculino , Auditoría Médica/normas , Auditoría Médica/tendencias , Estudios Retrospectivos , Adulto JovenRESUMEN
Neuromorphic computing is a brainlike information processing paradigm that requires adaptive learning mechanisms. A spiking neuro-evolutionary system is used for this purpose; plastic resistive memories are implemented as synapses in spiking neural networks. The evolutionary design process exploits parameter self-adaptation and allows the topology and synaptic weights to be evolved for each network in an autonomous manner. Variable resistive memories are the focus of this research; each synapse has its own conductance profile which modifies the plastic behaviour of the device and may be altered during evolution. These variable resistive networks are evaluated on a noisy robotic dynamic-reward scenario against two static resistive memories and a system containing standard connections only. The results indicate that the extra behavioural degrees of freedom available to the networks incorporating variable resistive memories enable them to outperform the comparative synapse types.
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Algoritmos , Inteligencia Artificial/tendencias , Equipos de Almacenamiento de Computador/tendencias , Metodologías Computacionales , Servicios de InformaciónRESUMEN
A rare cause of ST-segment elevation mimicking myocardial infarction has been reported in the setting of acute pneumothorax. We present a middle-aged woman with a right-sided secondary pneumothorax who developed severe chest pain associated with ST-segment elevation suggestive of acute myocardial infarction. Symptoms resolved immediately after advancement of the dislodged chest drain. A subsequent coronary angiogram was normal. This case highlights an uncommon electrocardiographic alteration and discusses possible pathophysiological mechanisms.
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Dolor en el Pecho/etiología , Neumotórax/terapia , Dolor en el Pecho/diagnóstico , Tubos Torácicos , Drenaje , Electrocardiografía , Femenino , Humanos , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Neumotórax/complicacionesRESUMEN
BACKGROUND: Global longitudinal strain (GLS) can predict cancer therapeutics-related cardiac dysfunction and guide initiation of cardioprotection (CPT). OBJECTIVES: In this study, the authors sought to determine whether echocardiography GLS-guided CPT provides less cardiac dysfunction in survivors of potentially cardiotoxic chemotherapy, compared with usual care at 3 years. METHODS: In this international multicenter prospective randomized controlled trial, patients were enrolled from 28 international sites. All patients treated with anthracyclines with another risk factor for heart failure were randomly allocated to GLS-guided (>12% relative reduction in GLS) or ejection fraction (EF)-guided (>10% absolute reduction of EF to <55%) CPT. The primary end point was the change in 3-dimensional (3D) EF (ΔEF) from baseline to 3 years. RESULTS: Among 331 patients enrolled, 255 (77%, age 54 ± 12 years, 95% women) completed 3-year follow-up (123 in the EF-guided group and 132 in the GLS-guided group). Most had breast cancer (n = 236; 93%), and anthracycline followed by trastuzumab was the most common chemotherapy regimen (84%). Although 67 (26%) had hypertension and 32 (13%) had diabetes mellitus, left ventricular function was normal at baseline (EF: 59% ± 6%, GLS: 20.7% ± 2.3%). CPT was administered in 18 patients (14.6%) in the EF-guided group and 41 (31%) in the GLS-guided group (P = 0.03). Most patients showed recovery in EF and GLS after chemotherapy; 3-year ΔEF was -0.03% ± 7.9% in the EF-guided group and -0.02% ± 6.5% in the GLS-guided (P = 0.99) group; respective 3-year EFs were 58% ± 6% and 59% ± 5% (P = 0.06). At 3 years, 17 patients (5%) had cancer therapeutics-related cardiac dysfunction (11 in the EF-guided group and 6 in the GLS guided group; P = 0.16); 1 patient in each group was admitted for heart failure. CONCLUSIONS: Among patients taking potentially cardiotoxic chemotherapy for cancer, the 3-year data showed improvement of LV dysfunction compared with 1 year, with no difference in ΔEF between GLS- and EF-guided CPT. (Strain Surveillance of Chemotherapy for Improving Cardiovascular Outcomes [SUCCOUR]; ACTRN12614000341628).
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Neoplasias de la Mama , Cardiopatías , Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Masculino , Estudios Prospectivos , Valor Predictivo de las Pruebas , Función Ventricular Izquierda , Disfunción Ventricular Izquierda/inducido químicamente , Disfunción Ventricular Izquierda/diagnóstico por imagen , Antibióticos Antineoplásicos/efectos adversos , Cardiotoxicidad/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Cardiopatías/inducido químicamente , Antraciclinas/efectos adversos , Insuficiencia Cardíaca/inducido químicamente , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/tratamiento farmacológico , Volumen SistólicoRESUMEN
Purpose: Diastolic waveforms in the left ventricular outflow tract (LVOT) are commonly observed with Doppler echocardiography. The incidence and mechanism are not well described. Methods: This was a retrospective observational study of 186 adult patients, athletes and non-athletes, free of known cardiac disease, presenting for comprehensive transthoracic echocardiography at a research institute. We aimed to evaluate the incidence and echocardiographic associations between LVOT diastolic waveforms. Results: Left ventricular outflow tract early to mid-diastolic waveforms were present in 100% of athletes and 95% of non-athletes. The LVOT diastolic velocity time integral was larger in athletes than non-athletes with a mean 8.3 cm (95% CI (7.6-8.9)) vs. 5.1 cm (4.4-5.9) (P < 0.0001). Multivariate predictors of this diastolic waveform were age (P = 0.002), slower heart rate (P = 0.035), higher stroke volume (P = 0.003), large mitral E (P = 0.019) and higher E/e' (P = 0.015). Discussion: An LVOT early diastolic wave is a normal physiological finding. It is related to a flow vortex redirecting diastolic mitral inflow around anterior mitral valve leaflet into the LVOT. Conclusions: Early to mid-diastolic LVOT waves are present in almost all patients but more prominent in young athletes than non-athletes. Diastolic LVOT waves increase with younger age, slower heart rate, larger stroke volume and enhanced diastolic function.
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PURPOSE: Antibiotic resistance is widespread throughout the world and represents a serious health concern. There is an urgent need for the development of novel tools for rapidly distinguishing antibiotic resistant bacteria from susceptible strains. Previous work has demonstrated that differences in antimicrobial susceptibility can be reflected in differences in the profile of volatile organic compounds (VOCs) produced by dissimilar strains. The aim of this study was to investigate the effect of the presence of cephalosporin antibiotics on the VOC profile of extended spectrum beta-lactamase (ESBL) and non-ESBL producing strains of Escherichia coli. MATERIAL AND METHODS: In this study, VOCs from strains of Escherichia coli positive and negative for the most commonly encountered ESBL, CTX-M in the presence of cephalosporin antibiotics were assessed using solid-phase microextraction (SPME) coupled with a combined gas chromatography-mass spectrometry/metal oxide sensor (GC-MS/MOS) system. RESULTS: Our proof-of-concept study allowed for distinguishing CTX-M positive and negative bacteria within 2 âh after the addition of antibiotics. One MOS signal (RT: 22.6) showed a statistically significant three-way interaction (p â= â0.033) in addition to significant two-way interactions for culture and additive (p â= â0.046) plus time and additive (p â= â0.020). There were also significant effects observed for time (p â= â0.009), culture (p â= â0.030) and additive (p â= â0.028). No effects were observed in the MS data. CONCLUSIONS: The results of our study showed the potential of VOC analysis using SPME combined with a GC-MS/MOS system for the early detection of CTX-M-producing, antibiotic-resistant E. coli, responsible for urinary tract infections (UTIs).
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Escherichia coli , Infecciones Urinarias , Antibacterianos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Humanos , Pruebas de Sensibilidad Microbiana , Óxidos , Microextracción en Fase Sólida , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/tratamiento farmacológico , beta-LactamasasRESUMEN
Colorectal symptoms are common but only infrequently represent serious pathology, including colorectal cancer (CRC). A large number of invasive tests are presently performed for reassurance. We investigated the feasibility of urinary volatile organic compound (VOC) testing as a potential triage tool in patients fast-tracked for assessment for possible CRC. A prospective, multi-center, observational feasibility study was performed across three sites. Patients referred to NHS fast-track pathways for potential CRC provided a urine sample that underwent Gas Chromatography-Mass Spectrometry (GC-MS), Field Asymmetric Ion Mobility Spectrometry (FAIMS), and Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) analysis. Patients underwent colonoscopy and/or CT colonography and were grouped as either CRC, adenomatous polyp(s), or controls to explore the diagnostic accuracy of VOC output data supported by an artificial neural network (ANN) model. 558 patients participated with 23 (4%) CRC diagnosed. 59% of colonoscopies and 86% of CT colonographies showed no abnormalities. Urinary VOC testing was feasible, acceptable to patients, and applicable within the clinical fast track pathway. GC-MS showed the highest clinical utility for CRC and polyp detection vs. controls (sensitivity = 0.878, specificity = 0.882, AUROC = 0.896) but it is labour intensive. Urinary VOC testing and analysis are feasible within NHS fast-track CRC pathways. Clinically meaningful differences between patients with cancer, polyps, or no pathology were identified suggesting VOC analysis may have future utility as a triage tool.