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1.
J Exp Clin Cancer Res ; 43(1): 15, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38195652

RESUMO

BACKGROUND: New drugs to tackle the next pathway or mutation fueling cancer are constantly proposed, but 97% of them are doomed to fail in clinical trials, largely because they are identified by cellular or in silico screens that cannot predict their in vivo effect. METHODS: We screened an Adeno-Associated Vector secretome library (> 1000 clones) directly in vivo in a mouse model of cancer and validated the therapeutic effect of the first hit, EMID2, in both orthotopic and genetic models of lung and pancreatic cancer. RESULTS: EMID2 overexpression inhibited both tumor growth and metastatic dissemination, consistent with prolonged survival of patients with high levels of EMID2 expression in the most aggressive human cancers. Mechanistically, EMID2 inhibited TGFß maturation and activation of cancer-associated fibroblasts, resulting in more elastic ECM and reduced levels of YAP in the nuclei of cancer cells. CONCLUSION: This is the first in vivo screening, precisely designed to identify proteins able to interfere with cancer cell invasiveness. EMID2 was selected as the most potent protein, in line with the emerging relevance of the tumor extracellular matrix in controlling cancer cell invasiveness and dissemination, which kills most of cancer patients.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , Núcleo Celular , Modelos Animais de Doenças , Detecção Precoce de Câncer , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Colágeno/metabolismo
2.
Circ Res ; 133(8): 687-703, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37681309

RESUMO

BACKGROUND: Heart failure is typical in the elderly. Metabolic remodeling of cardiomyocytes underlies inexorable deterioration of cardiac function with aging: glycolysis increases at the expense of oxidative phosphorylation, causing an energy deficit contributing to impaired contractility. Better understanding of the mechanisms of this metabolic switching could be critical for reversing the condition. METHODS: To investigate the role of 3 histone modifications (H3K27ac, H3K27me3, and H3K4me1) in the metabolic remodeling occurring in the aging heart, we cross-compared epigenomic, transcriptomic, and metabolomic data from mice of different ages. In addition, the role of the transcriptional coactivator p300 (E1A-associated binding protein p300)/CBP (CREB binding protein) in cardiac aging was investigated using a specific inhibitor of this histone acetyltransferase enzyme. RESULTS: We report a set of species-conserved enhancers associated with transcriptional changes underlying age-related metabolic remodeling in cardiomyocytes. Activation of the enhancer region of Hk2-a key glycolysis pathway gene-was fostered in old age-onset mouse heart by pseudohypoxia, wherein hypoxia-related genes are expressed under normal O2 levels, via increased activity of P300/CBP. Pharmacological inhibition of this transcriptional coactivator before the onset of cardiac aging led to a more aerobic, less glycolytic, metabolic state, improved heart contractility, and overall blunting of cardiac decline. CONCLUSIONS: Taken together, our results suggest how epigenetic dysregulation of glycolysis pathway enhancers could potentially be targeted to treat heart failure in the elderly.


Assuntos
Insuficiência Cardíaca , Fatores de Transcrição , Humanos , Camundongos , Animais , Idoso , Histona Acetiltransferases , Sequências Reguladoras de Ácido Nucleico , Transcriptoma , Ativação Transcricional
3.
Front Cardiovasc Med ; 10: 1216917, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37408655

RESUMO

Background: Reliable biomarkers for assessing the viability of the donor hearts undergoing ex vivo perfusion remain elusive. A unique feature of normothermic ex vivo perfusion on the TransMedics® Organ Care System (OCS™) is that the donor heart is maintained in a beating state throughout the preservation period. We applied a video algorithm for an in vivo assessment of cardiac kinematics, video kinematic evaluation (Vi.Ki.E.), to the donor hearts undergoing ex vivo perfusion on the OCS™ to assess the feasibility of applying this algorithm in this setting. Methods: Healthy donor porcine hearts (n = 6) were procured from Yucatan pigs and underwent 2 h of normothermic ex vivo perfusion on the OCS™ device. During the preservation period, serial high-resolution videos were captured at 30 frames per second. Using Vi.Ki.E., we assessed the force, energy, contractility, and trajectory parameters of each heart. Results: There were no significant changes in any of the measured parameters of the heart on the OCS™ device over time as judged by linear regression analysis. Importantly, there were no significant changes in contractility during the duration of the preservation period (time 0-30 min, 918 ± 430 px/s; time 31-60 min, 1,386 ± 603 px/s; time 61-90 min, 1,299 ± 617 px/s; time 91-120 min, 1,535 ± 728 px/s). Similarly, there were no significant changes in the force, energy, or trajectory parameters. Post-transplantation echocardiograms demonstrated robust contractility of each allograft. Conclusion: Vi.Ki.E. assessment of the donor hearts undergoing ex vivo perfusion is feasible on the TransMedics OCS™, and we observed that the donor hearts maintain steady kinematic measurements throughout the duration.

4.
Pflugers Arch ; 475(6): 731-745, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37022463

RESUMO

The effects of excitability, refractoriness, and impulse conduction have been independently related to enhanced arrhythmias in the aged myocardium in experimental and clinical studies. However, their combined arrhythmic effects in the elderly are not yet completely understood. Hence, the aim of the present work is to relate relevant cardiac electrophysiological parameters to enhanced arrhythmia vulnerability in the in vivo senescent heart. We used multiple-lead epicardial potential mapping in control (9-month-old) and aged (24-month-old) rat hearts. Cardiac excitability and refractoriness were evaluated at numerous epicardial test sites by means of the strength-duration curve and effective refractory period, respectively. During sinus rhythm, durations of electrogram intervals and waves were prolonged in the senescent heart, compared with control, demonstrating a latency in tissue activation and recovery. During ventricular pacing, cardiac excitability, effective refractory period, and dispersion of refractoriness increased in the aged animal. This scenario was accompanied by impairment of impulse propagation. Moreover, both spontaneous and induced arrhythmias were increased in senescent cardiac tissue. Histopathological evaluation of aged heart specimens revealed connective tissue deposition and perinuclear myocytolysis in the atria, while scattered microfoci of interstitial fibrosis were mostly present in the ventricular subendocardium. This work suggests that enhanced arrhythmogenesis in the elderly is a multifactorial process due to the joint increase in excitability and dispersion of refractoriness in association with enhanced conduction inhomogeneity. The knowledge of these electrophysiological changes will possibly contribute to improved prevention of the age-associated increase in cardiac arrhythmias.


Assuntos
Arritmias Cardíacas , Sistema de Condução Cardíaco , Masculino , Ratos , Animais , Miocárdio , Ventrículos do Coração , Átrios do Coração
5.
Nat Commun ; 13(1): 6, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013167

RESUMO

Myocardial infarction causes 7.3 million deaths worldwide, mostly for fibrillation that electrically originates from the damaged areas of the left ventricle. Conventional cardiac bypass graft and percutaneous coronary interventions allow reperfusion of the downstream tissue but do not counteract the bioelectrical alteration originated from the infarct area. Genetic, cellular, and tissue engineering therapies are promising avenues but require days/months for permitting proper functional tissue regeneration. Here we engineered biocompatible silicon carbide semiconductive nanowires that synthetically couple, via membrane nanobridge formations, isolated beating cardiomyocytes over distance, restoring physiological cell-cell conductance, thereby permitting the synchronization of bioelectrical activity in otherwise uncoupled cells. Local in-situ multiple injections of nanowires in the left ventricular infarcted regions allow rapid reinstatement of impulse propagation across damaged areas and recover electrogram parameters and conduction velocity. Here we propose this nanomedical intervention as a strategy for reducing ventricular arrhythmia after acute myocardial infarction.


Assuntos
Infarto do Miocárdio , Miócitos Cardíacos/fisiologia , Nanofios , Arritmias Cardíacas/terapia , Compostos Inorgânicos de Carbono , Ventrículos do Coração , Humanos , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Compostos de Silício
6.
J Clin Med ; 10(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34830612

RESUMO

The human right ventricle is barely monitored during open-chest surgery due to the absence of intraoperative imaging techniques capable of elaborating its complex function. Accordingly, artificial intelligence could not be adopted for this specific task. We recently proposed a video-based approach for the real-time evaluation of the epicardial kinematics to support medical decisions. Here, we employed two supervised machine learning algorithms based on our technique to predict the patients' outcomes before chest closure. Videos of the beating hearts were acquired before and after pulmonary valve replacement in twelve Tetralogy of Fallot patients and recordings were properly labeled as the "unhealthy" and "healthy" classes. We extracted frequency-domain-related features to train different supervised machine learning models and selected their best characteristics via 10-fold cross-validation and optimization processes. Decision surfaces were built to classify two additional patients having good and unfavorable clinical outcomes. The k-nearest neighbors and support vector machine showed the highest prediction accuracy; the patients' class was identified with a true positive rate ≥95% and the decision surfaces correctly classified the additional patients in the "healthy" (good outcome) or "unhealthy" (unfavorable outcome) classes. We demonstrated that classifiers employed with our video-based technique may aid cardiac surgeons in decision making before chest closure.

7.
Environ Pollut ; 284: 117163, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33910133

RESUMO

Air pollution is well recognized as a central player in cardiovascular disease. Exhaust particulate from diesel engines (DEP) is rich in nanoparticles and may contribute to the health effects of particulate matter in the environment. Moreover, diesel soot emitted by modern engines denotes defective surfaces alongside chemically-reactive sites increasing soot cytotoxicity. We recently demonstrated that engineered nanoparticles can cross the air/blood barrier and are capable to reach the heart. We hypothesize that DEP nanoparticles are pro-arrhythmogenic by direct interaction with cardiac cells. We evaluated the internalization kinetics and the effects of DEP, collected from Euro III (DEPe3, in the absence of Diesel Particulate Filter, DPF) and Euro IV (DEPe4, in the presence of DPF) engines, on alveolar and cardiac cell lines and on in situ rat hearts following DEP tracheal instillation. We observed significant differences in DEP size, metal and organic compositions derived from both engines. DEPe4 comprised ultrafine particles (<100 nm) and denoted a more pronounced toxicological outcome compared to DEPe3. In cardiomyocytes, particle internalization is fastened for DEPe4 compared to DEPe3. The in-vivo epicardial recording shows significant alteration of EGs parameters in both groups. However, the DEPe4-instilled group showed, compared to DEPe3, a significant increment of the effective refractory period, cardiac conduction velocity, and likelihood of arrhythmic events, with a significant increment of membrane lipid peroxidation but no increment in inflammation biomarkers. Our data suggest that DEPe4, possibly due to ultrafine nanoparticles, is rapidly internalized by cardiomyocytes resulting in an acute susceptibility to cardiac electrical disorder and arrhythmias that could accrue from cellular toxicity. Since the postulated transfer of nanoparticles from the lung to myocardial cells has not been investigated it remains open whether the effects on the cardiovascular function are the result of lung inflammatory reactions or due to particles that have reached the heart.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Nanopartículas , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Animais , Arritmias Cardíacas/induzido quimicamente , Nanopartículas/toxicidade , Material Particulado/análise , Material Particulado/toxicidade , Ratos , Emissões de Veículos/análise , Emissões de Veículos/toxicidade
8.
Eur J Cardiothorac Surg ; 59(6): 1329-1336, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-33547473

RESUMO

OBJECTIVES: Indications for and timing of pulmonary valve replacement (PVR) after tetralogy of Fallot repair are controversial. Among magnetic resonance imaging indices proposed to time valve replacement, a right ventricular (RV) end-diastolic volume index greater than 160 ml/m2 is often used. Recent evidence suggests that this value may still identify patients with irreversible RV dysfunction, thus hindering recovery. Our goal was to define, using intraoperative video kinematic evaluation, whether a relationship exists between timing of PVR and early functional recovery after surgery. METHODS: Between November 2016 and November 2018, a total of 12 consecutive patients aged 27.1 ± 19.1 years underwent PVR on average 22.2 ± 13.3 years after tetralogy of Fallot repair. Mean RV end-diastolic volume evident on the magnetic resonance images was 136.9 ± 35.7 ml/m2. Intraoperative cardiac kinematics were assessed by video kinematic evaluation via a high-speed camera acquiring videos at 200 fps before and after valve replacement. RESULTS: Patients presenting with RV end-diastolic volume <147 ml/m2 were significantly younger (11.2 ± 5.0 vs 38.4 ± 17.0; P = 0.005) and had a shorter time interval to valve replacement (11.0 ± 5.2 vs 30.1 ± 11.3; P = 0.03). The entire population showed a moderate correlation among energy expenditure, cardiac fatigue, perimeter of contraction and preoperative RV end-diastolic volume index. Both groups showed a reduction in all kinematic parameters after PVR, but those with end-diastolic volume >147 ml/m2 showed an unpredictable outcome. CONCLUSIONS: Video kinematic evaluation provides insight into intraoperative RV recovery in patients with tetralogy of Fallot undergoing PVR. Accordingly, functional recovery can be expected in patients with preoperative end-diastolic volume <147 ml/m2.


Assuntos
Insuficiência da Valva Pulmonar , Valva Pulmonar , Tetralogia de Fallot , Fenômenos Biomecânicos , Humanos , Resultado do Tratamento
9.
Sensors (Basel) ; 22(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35009792

RESUMO

Home monitoring supports the continuous improvement of the therapy by sharing data with healthcare professionals. It is required when life-threatening events can still occur after hospital discharge such as neonatal apnea. However, multiple sources of external noise could affect data quality and/or increase the misdetection rate. In this study, we developed a mechatronic platform for sensor characterizations and a framework to manage data in the context of neonatal apnea. The platform can simulate the movement of the abdomen in different plausible newborn positions by merging data acquired simultaneously from three-axis accelerometers and infrared sensors. We simulated nine apnea conditions combining three different linear displacements and body postures in the presence of self-generated external noise, showing how it is possible to reduce errors near to zero in phenomena detection. Finally, the development of a smart 8Ws-based software and a customizable mobile application were proposed to facilitate data management and interpretation, classifying the alerts to guarantee the correct information sharing without specialized skills.


Assuntos
Biônica , Aplicativos Móveis , Humanos , Recém-Nascido
10.
Prog Biophys Mol Biol ; 154: 94-101, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31126627

RESUMO

BACKGROUND: Gender-related cardiac mechanics following the electrical activity has been investigated from basic to clinical research, but results are still controversial. The aim of this work is to study the gender related cardiac mechanics and to focus on its heart rate dependency. METHODS: We employed 12 Sprague Dawley rats (5 males and 7 females) of the same age and, through a novel high resolution artificial vision contactless approach, we evaluated in-situ cardiac kinematic. The hearts were paced on the right atria appendage via cathodal stimuli at rising frequency. RESULTS: Kinematic data obtained at rising pacing rates are different between male and female rat hearts: male tended to maintain the same level of cardiac force, energy and contractility, while female responded with an increment of such parameters at increasing heart rate. Female hearts preserved their pattern of contraction and epicardial torsion (vorticity) at rising pacing rates compared to male. Furthermore, we observed a difference in the mechanical restitution: systolic time vs. diastolic time, as an index of cardiac performance, reached higher value in male compared to female hearts. CONCLUSION: Our innovative technology was capable to evaluate in-situ rat epicardial kinematic at high stimulation frequency, revealing that male preserved kinematic parameters but varying the pattern of contraction/relaxation. On the contrary, female preserved the pattern of contraction/relaxation increasing kinematic parameters.


Assuntos
Fenômenos Mecânicos , Pericárdio/fisiologia , Caracteres Sexuais , Animais , Fenômenos Biomecânicos , Diástole/fisiologia , Feminino , Frequência Cardíaca , Masculino , Contração Miocárdica/fisiologia , Ratos , Ratos Sprague-Dawley
11.
Interact Cardiovasc Thorac Surg ; 29(4): 625-631, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31177278

RESUMO

OBJECTIVES: The timing for pulmonary valve replacement (PVR) after tetralogy of Fallot repair is controversial, due to limitations in estimating right ventricular dysfunction and recovery. Intraoperative imaging could add prognostic information, but transoesophageal echocardiography is unsuitable for exploring right heart function. Right ventricular function after PVR was investigated in real time using a novel video-based contactless kinematic evaluation technology (Vi.Ki.E.), which calculates cardiac fatigue and energy consumption. METHODS: Six consecutive patients undergoing PVR at 13.8 ± 2.6 years (range 6.9-19.8) after the repair of tetralogy of Fallot were enrolled. Mean right ventricular end-diastolic and end-systolic volume at magnetic resonance imaging were 115.6 ± 16.2 ml/m2 and 61.5 ± 14.6 ml/m2, respectively. Vi.Ki.E. uses a fast-resolution camera placed 45 cm above the open chest, recording cardiac kinematics before and after PVR. An algorithm defines cardiac parameters, such as energy, fatigue, maximum contraction velocity and tissue displacement. RESULTS: There were no perioperative complications, with patients discharged in satisfactory clinical conditions after 7 ± 2 days (range 5-9). Vi.Ki.E. parameters describing right ventricular dysfunction decreased significantly after surgery: energy consumption by 45% [271 125 ± 9422 (mm/s)2 vs 149 202 ± 11 980 (mm/s)2, P = 0.0001], cardiac fatigue by 12% (292 671 ± 29 369 mm/s2 vs 258 755 ± 42 750 mm/s2, P = 0.01), contraction velocity by 54% (3412 ± 749 mm/s vs 1579 ± 400 mm/s, P = 0.0007) and displacement by 23% (27 ± 4 mm vs 21 ± 4 mm, P = 0.01). Patients undergoing PVR at lower end-diastolic volumes, had greater functional recovery of Vi.Ki.E. parameters. CONCLUSIONS: Intraoperative Vi.Ki.E shows immediate recovery of right ventricular mechanics after PVR with less cardiac fatigue and energy consumption, providing novel insights that may have a prognostic relevance for functional recovery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/cirurgia , Tetralogia de Fallot/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Disfunção Ventricular Direita/diagnóstico por imagem , Adolescente , Fenômenos Biomecânicos , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Projetos Piloto , Prognóstico , Insuficiência da Valva Pulmonar/complicações , Tetralogia de Fallot/complicações , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Adulto Jovem
12.
Sci Rep ; 7: 46143, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28397830

RESUMO

Mechanical function of the heart during open-chest cardiac surgery is exclusively monitored by echocardiographic techniques. However, little is known about local kinematics, particularly for the reperfused regions after ischemic events. We report a novel imaging modality, which extracts local and global kinematic parameters from videos of in situ beating hearts, displaying live video cardiograms of the contraction events. A custom algorithm tracked the movement of a video marker positioned ad hoc onto a selected area and analyzed, during the entire recording, the contraction trajectory, displacement, velocity, acceleration, kinetic energy and force. Moreover, global epicardial velocity and vorticity were analyzed by means of Particle Image Velocimetry tool. We validated our new technique by i) computational modeling of cardiac ischemia, ii) video recordings of ischemic/reperfused rat hearts, iii) videos of beating human hearts before and after coronary artery bypass graft, and iv) local Frank-Starling effect. In rats, we observed a decrement of kinematic parameters during acute ischemia and a significant increment in the same region after reperfusion. We detected similar behavior in operated patients. This modality adds important functional values on cardiac outcomes and supports the intervention in a contact-free and non-invasive mode. Moreover, it does not require particular operator-dependent skills.


Assuntos
Coração/fisiopatologia , Gravação em Vídeo , Animais , Bloqueio Atrioventricular , Fenômenos Biomecânicos , Simulação por Computador , Ponte de Artéria Coronária , Diástole/fisiologia , Feminino , Humanos , Masculino , Contração Miocárdica/fisiologia , Reperfusão Miocárdica , Ratos , Reprodutibilidade dos Testes , Reologia , Sístole/fisiologia
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