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1.
Lab Invest ; 102(8): 814-825, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35437316

RESUMO

As the coronavirus disease 2019 (COVID-19) pandemic evolves, much evidence implicates the heart as a critical target of injury in patients. The mechanism(s) of cardiac involvement has not been fully elucidated, although evidence of direct virus-mediated injury, thromboembolism with ischemic complications, and cytokine storm has been reported. We examined suggested mechanisms of COVID-19-associated heart failure in 21 COVID-19-positive decedents, obtained through standard autopsy procedure, compared to clinically matched controls and patients with various etiologies of viral myocarditis. We developed a custom tissue microarray using regions of pathological interest and interrogated tissues via immunohistochemistry and in situ hybridization. Severe acute respiratory syndrome coronavirus 2 was detected in 16/21 patients, in cardiomyocytes, the endothelium, interstitial spaces, and percolating adipocytes within the myocardium. Virus detection typically corresponded with troponin depletion and increased cleaved caspase-3. Indirect mechanisms of injury-venous and arterial thromboses with associated vasculitis including a mixed inflammatory infiltrate-were also observed. Neutrophil extracellular traps (NETs) were present in the myocardium of all COVID-19 patients, regardless of injury degree. Borderline myocarditis (inflammation without associated myocyte injury) was observed in 19/21 patients, characterized by a predominantly mononuclear inflammatory infiltrate. Edema, inflammation of percolating adipocytes, lymphocytic aggregates, and large septal masses of inflammatory cells and platelets were observed as defining features, and myofibrillar damage was evident in all patients. Collectively, COVID-19-associated cardiac injury was multifactorial, with elevated levels of NETs and von Willebrand factor as defining features of direct and indirect viral injury.


Assuntos
COVID-19 , Miocardite , Autopsia , COVID-19/complicações , Humanos , Inflamação , Miócitos Cardíacos
2.
Am J Physiol Heart Circ Physiol ; 322(2): H145-H155, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890276

RESUMO

Neutrophils infiltrate into the left ventricle (LV) early after myocardial infarction (MI) and launch a proinflammatory response. Along with neutrophil infiltration, LV wall thinning due to cardiomyocyte necrosis also peaks at day 1 in the mouse model of MI. To understand the correlation, we examined a previously published data set that included day 0 (n = 10) and MI day (D) 1 (n = 10) neutrophil proteome and echocardiography assessments. Out of 123 proteins, 4 proteins positively correlated with the infarct wall thinning index (1/wall thickness): histone 1.2 (r = 0.62, P = 0.004), S100A9 (r = 0.60, P = 0.005), histone 3.1 (r = 0.55, P = 0.01), and fibrinogen (r = 0.47, P = 0.04). As S100A9 was the highest ranked secreted protein, we hypothesized that S100A9 is a functional effector of infarct wall thinning. We exogenously administered S100A8/A9 at the time of MI to mice [C57BL/6J, male, 3-6 mo of age, n = 7 M (D1), and n = 5 M (D3)] and compared with saline vehicle control-treated mice [n = 6 M (D1) and n = 6 M (D3)] at MI days 1 and 3. At MI day 3, the S100A8/A9 group showed a 22% increase in the wall thinning index compared with saline (P = 0.02), along with higher dilation and lower ejection fraction. The decline in cardiac physiology occurred subsequent to increased neutrophil and macrophage infiltration at MI day 1 and increased macrophage infiltration at D3. Our results reveal that S100A9 is a functional effector of infarct wall thinning.NEW & NOTEWORTHY S100A9 is a functional marker of infarct wall thinning.


Assuntos
Calgranulina B/metabolismo , Infarto do Miocárdio/metabolismo , Animais , Calgranulina B/genética , Células Cultivadas , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Neutrófilos/metabolismo , Proteoma/genética , Proteoma/metabolismo
3.
Ann Rheum Dis ; 80(11): 1385-1392, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34049859

RESUMO

OBJECTIVE: Examine the association of methotrexate (MTX) use with cardiovascular disease (CVD) in rheumatoid arthritis (RA) using marginal structural models (MSM) and determine if CVD risk is mediated through modification of disease activity. METHODS: We identified incident CVD events (coronary artery disease (CAD), stroke, heart failure (HF) hospitalisation, CVD death) within a multicentre, prospective cohort of US Veterans with RA. A 28-joint Disease Activity Score with C-reactive protein (DAS28-CRP) was collected at regular visits and medication exposures were determined by linking to pharmacy dispensing data. MSMs were used to estimate the treatment effect of MTX on risk of incident CVD, accounting for time-varying confounders between receiving MTX and CVD events. A mediation analysis was performed to estimate the indirect effects of methotrexate on CVD risk through modification of RA disease activity. RESULTS: Among 2044 RA patients (90% male, mean age 63.9 years, baseline DAS28-CRP 3.6), there were 378 incident CVD events. Using MSM, MTX use was associated with a 24% reduced risk of composite CVD events (HR 0.76, 95% CI 0.58 to 0.99) including a 57% reduction in HF hospitalisations (HR 0.43, 95% CI 0.24 to 0.77). Individual associations with CAD, stroke and CVD death were not statistically significant. In mediation analyses, there was no evidence of indirect effects of MTX on CVD risk through disease activity modification (HR 1.03, 95% CI 0.80 to 1.32). CONCLUSIONS: MTX use in RA was associated with a reduced risk of CVD events, particularly HF-related hospitalisations. These associations were not mediated through reductions in RA disease activity, suggesting alternative MTX-related mechanisms may modify CVD risk in this population.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Doença da Artéria Coronariana/epidemiologia , Fatores de Risco de Doenças Cardíacas , Insuficiência Cardíaca/epidemiologia , Hospitalização/estatística & dados numéricos , Metotrexato/uso terapêutico , Acidente Vascular Cerebral/epidemiologia , Idoso , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/fisiopatologia , Doenças Cardiovasculares/mortalidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais
4.
J Vasc Interv Radiol ; 32(3): 439-446, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33414069

RESUMO

PURPOSE: To determine physician radiation exposure when using partial-angle computed tomography (CT) fluoroscopy (PACT) vs conventional full-rotation CT and whether there is an optimal tube/detector position at which physician dose is minimized. MATERIALS AND METHODS: Physician radiation dose (entrance air kerma) was measured for full-rotation CT (360°) and PACT (240°) at all tube/detector positions using a human-mimicking phantom placed in a 64-channel multidetector CT. Parameters included 120 kV, 20- and 40-mm collimation, and 100 mA. The mean, standard deviation, and increase/decrease in physician dose compared with a full-rotation scan were reported. RESULTS: Physician radiation exposure during CT fluoroscopy with PACT was highly dependent on the position of the tube/detector during scanning. The lowest PACT physician dose was when the physician was on the detector side (center view angle 116°; -35% decreased dose vs full-angle CT). The highest PACT physician dose was with the physician on the tube side (center view angle 298°; +34% increased dose vs full-angle CT), all doses P <.05 vs full-rotation CT. CONCLUSIONS: Partial-angle CT has the potential to both significantly increase or decrease physician radiation dose during CT fluoroscopy-guided procedures. The detector/tube position has a profound effect on physician dose. The lowest dose during PACT was achieved when the physician was located on the detector side (ie, distant from the tube). This data could be used to optimize CT fluoroscopy parameters to reduce physician radiation exposure for PACT-capable scanners.


Assuntos
Tomografia Computadorizada Multidetectores , Exposição Ocupacional , Doses de Radiação , Exposição à Radiação , Radiografia Intervencionista , Radiologistas , Fluoroscopia , Humanos , Tomografia Computadorizada Multidetectores/efeitos adversos , Tomografia Computadorizada Multidetectores/instrumentação , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/prevenção & controle , Saúde Ocupacional , Imagens de Fantasmas , Exposição à Radiação/efeitos adversos , Exposição à Radiação/prevenção & controle , Radiografia Intervencionista/efeitos adversos , Radiografia Intervencionista/instrumentação , Medição de Risco , Fatores de Risco , Tomógrafos Computadorizados
5.
Proc Natl Acad Sci U S A ; 115(40): 9867-9874, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30275303

RESUMO

To comprehend edited video, viewers must infer the meaning conveyed by successive video shots (i.e., continuous video segments separated by edit points, such as camera cuts). The central question here was whether comprehension-related top-down cognitive processes drive eye movements during sequential processing of video montage. Eye movements were recorded as 4 year olds and adults (n = 62) watched a video with the same constituent shots in either normal or random sequence. The key analyses compared eye movements to constituent shots when presented in normal order with those to the same shots presented in random order. The dependent variable was attentional synchrony or the extent to which viewers looked at the same location at the same time, indicating commonality of processing the video. This was calculated as the bivariate contour ellipse area within which points of gaze fell during each video frame. Results indicated that children were more scattered in their gaze locations than adults. Viewers became more similar to each other as normal vignettes unfolded over time; this was especially true in adults and possibly reflects a growing and shared understanding of the content. Conversely, adult attentional synchrony was reduced when watching random shot sequences. Thus, attentional synchrony during normal video viewing is driven not only by salient visual features, such as movement and areas of high contrast, but also, by the unfolding sequential comprehension of video montage, especially in adults. Differences between children and adults indicate that this top-down control of eye movements while watching video changes systematically over development.


Assuntos
Atenção/fisiologia , Compreensão/fisiologia , Fixação Ocular/fisiologia , Multimídia , Adulto , Pré-Escolar , Feminino , Humanos , Masculino
6.
Int J Mol Sci ; 22(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34884754

RESUMO

Chronic inflammation plays a critical role in the pathogenesis of atherosclerosis. Currently, the mechanism(s) by which inflammation contributes to this disease are not entirely understood. Inflammation is known to induce oxidative stress, which can lead to lipid peroxidation. Lipid peroxidation can result in the production of reactive by-products that can oxidatively modify macromolecules including DNA, proteins, and lipoproteins. A major reactive by-product of lipid peroxidation is malondialdehyde (MDA). MDA can subsequently break down to form acetaldehyde (AA). These two aldehydes can covalently interact with the epsilon (ε)-amino group of lysines within proteins and lipoproteins leading to the formation of extremely stable, highly immunogenic malondialdehyde/acetaldehyde adducts (MAA-adducts). The aim of this study was to investigate the inflammatory response to MAA-modified human serum albumin (HSA-MAA) and low-density lipoprotein (LDL-MAA). We found that animals injected with LDL-MAA generate antibodies specific to MAA-adducts. The level of anti-MAA antibodies were further increased in an animal model of atherosclerosis fed a Western diet. An animal model that combined both high fat diet and immunization of MAA-modified protein resulted in a dramatic increase in antibodies to MAA-adducts and vascular fat accumulation compared with controls. In vitro exposure of endothelial cells and macrophages to MAA-modified proteins resulted in increased fat accumulation as well as increased expression of adhesion molecules and pro-inflammatory cytokines. The expression of cytokines varied between the different cell lines and was unique to the individual modified proteins. The results of these studies demonstrate that different MAA-modified proteins elicit unique responses in different cell types. Additionally, the presence of MAA-modified proteins appears to modulate cellular metabolism leading to increased accumulation of triglycerides and further progression of the inflammatory response.


Assuntos
Inflamação/metabolismo , Lipoproteínas LDL/imunologia , Lipoproteínas LDL/metabolismo , Processamento de Proteína Pós-Traducional , Albumina Sérica Humana/imunologia , Albumina Sérica Humana/metabolismo , Acetaldeído/metabolismo , Animais , Aterosclerose/etiologia , Aterosclerose/imunologia , Aterosclerose/metabolismo , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/metabolismo , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Feminino , Humanos , Inflamação/etiologia , Inflamação/imunologia , Metabolismo dos Lipídeos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley
7.
Am J Physiol Heart Circ Physiol ; 319(6): H1414-H1437, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33064567

RESUMO

Increased matrix metalloprotease 9 (MMP9) after myocardial infarction (MI) exacerbates ischemia-induced chronic heart failure (CHF). Autophagy is cardioprotective during CHF; however, whether increased MMP9 suppresses autophagic activity in CHF is unknown. This study aimed to determine whether increased MMP9 suppressed autophagic flux and MMP9 inhibition increased autophagic flux in the heart of rats with post-MI CHF. Sprague-Dawley rats underwent either sham surgery or coronary artery ligation 6-8 wk before being treated with MMP9 inhibitor for 7 days, followed by cardiac autophagic flux measurement with lysosomal inhibitor bafilomycin A1. Furthermore, autophagic flux was measured in vitro by treating H9c2 cardiomyocytes with two independent pharmacological MMP9 inhibitors, salvianolic acid B (SalB) and MMP9 inhibitor-I, and CRISPR/cas9-mediated MMP9 genetic ablation. CHF rats showed cardiac infarct, significantly increased left ventricular end-diastolic pressure (LVEDP), and increased MMP9 activity and fibrosis in the peri-infarct areas of left ventricular myocardium. Measurement of the autophagic markers LC3B-II and p62 with lysosomal inhibition showed decreased autophagic flux in the peri-infarct myocardium. Treatment with SalB for 7 days in CHF rats decreased MMP9 activity and cardiac fibrosis but increased autophagic flux in the peri-infarct myocardium. As an in vitro corollary study, measurement of autophagic flux in H9c2 cardiomyocytes and fibroblasts showed that pharmacological inhibition or genetic ablation of MMP9 upregulates autophagic flux. These data are consistent with our observations that MMP9 inhibition upregulates autophagic flux in the heart of rats with CHF. In conclusion, the results in this study suggest that the beneficial outcome of MMP9 inhibition in pathological cardiac remodeling is in part mediated by improved autophagic flux.NEW & NOTEWORTHY This study elucidates that the improved cardiac extracellular matrix (ECM) remodeling and cardioprotective effect of matrix metalloprotease 9 (MMP9) inhibition in chronic heart failure (CHF) are via increased autophagic flux. Autophagy is cardioprotective; however, the mechanism of autophagy suppression in CHF is unknown. We for the first time demonstrated here that increased MMP9 suppressed cardiac autophagy and ablation of MMP9 increased cardiac autophagic flux in CHF rats. Restoring the physiological level of autophagy in the failing heart is a challenge, and our study addressed this challenge. The novelty and highlights of this report are as follows: 1) MMP9 regulates cardiomyocyte and fibroblast autophagy, 2) MMP9 inhibition protects CHF after myocardial infarction (MI) via increased cardiac autophagic flux, 3) MMP9 inhibition increased cardiac autophagy via activation of AMP-activated protein kinase (AMPK)α, Beclin-1, Atg7 pathway and suppressed mechanistic target of rapamycin (mTOR) pathway.


Assuntos
Autofagia/efeitos dos fármacos , Benzofuranos/farmacologia , Fibroblastos/efeitos dos fármacos , Insuficiência Cardíaca/tratamento farmacológico , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Animais , Linhagem Celular , Modelos Animais de Doenças , Fibroblastos/enzimologia , Fibroblastos/patologia , Fibrose , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Masculino , Metaloproteinase 9 da Matriz/genética , Camundongos , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Ratos Sprague-Dawley , Transdução de Sinais , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
8.
J Card Fail ; 26(10): 876-884, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32446948

RESUMO

Heart failure (HF) has traditionally been defined by symptoms of fluid accumulation and poor perfusion, but it is now recognized that specific HF classifications hold prognostic and therapeutic relevance. Specifically, HF with reduced ejection fraction is characterized by reduced left ventricular systolic pump function and dilation and HF with preserved ejection fraction is characterized primarily by abnormal left ventricular filling (diastolic failure) with relatively preserved left ventricular systolic function. These forms of HF are distributed equally among patients with HF and likely require distinctly different strategies to mitigate the morbidity, mortality, and medical resource utilization of this disease. In particular, HF is a significant medical issue within the US Department of Veterans Affairs (VA) hospital system and constitutes a major translational research priority for the VA. Because a common underpinning of both HF with reduced ejection fraction and HF with preserved ejection fraction seems to be changes in the structure and function of the myocardial extracellular matrix, a conference was convened sponsored by the VA, entitled, "Targeting Myocardial Fibrosis in Heart Failure" to explore the extracellular matrix as a potential therapeutic target and to propose specific research directions. The conference was conceptually framed around the hypothesis that although HF with reduced ejection fraction and HF with preserved ejection fraction clearly have distinct mechanisms, they may share modifiable pathways and biological mediators in common. Inflammation and extracellular matrix were identified as major converging themes. A summary of our discussion on unmet challenges and possible solutions to move the field forward, as well as recommendations for future research opportunities, are provided.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Diástole , Fibrose , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Humanos , Volume Sistólico , Função Ventricular Esquerda
9.
J Appl Clin Med Phys ; 20(12): 25-35, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31675460

RESUMO

Patient dose from 2.5 MV images on the TrueBeam linear accelerator is not easily quantified, primarily because this beam energy is not normally modeled by commercial treatment planning systems. In this work we present the feasibility of using the Eclipse® treatment planning system to model this beam. The Acuros XB and the AAA dose calculation algorithms were tested. Profiles, PDDs, and output factors were measured for the 2.5 MV unflattened imaging beam and used for beam modeling. The algorithms were subsequently verified using MPPG 5.a guidelines. Calculated doses with both algorithms agreed with the measurement data to within the following criteria recommended for conventional therapeutic MV beams: 2% local dose-difference in the high-dose region, 3% global difference in the low-dose region, 3 mm distance to agreement in the penumbra, and a gamma pass rate of >95% for 3%/3 mm criteria. Acuros was able to accurately calculate dose through cork and bone-equivalent heterogeneities. AAA was able to accurately calculate dose through the bone-equivalent heterogeneity but did not pass within the recommended criteria for the cork heterogeneity. For the 2.5 MV imaging beam, both the AAA and Acuros algorithms provide calculated doses that agree with measured results well within the 20% criteria for imaging beams recommended by AAPM TG-180.


Assuntos
Algoritmos , Neoplasias/radioterapia , Aceleradores de Partículas/instrumentação , Planejamento de Assistência ao Paciente/normas , Imagens de Fantasmas , Fótons/uso terapêutico , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica
10.
Am J Physiol Gastrointest Liver Physiol ; 314(3): G418-G430, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29351393

RESUMO

Precision-cut liver slices (PCLSs) provide a novel model for studies of alcoholic liver disease (ALD). This is relevant, as in vivo ethanol exposure does not appear to generate significant liver damage in ethanol-fed mice, except in the National Institute on Alcohol Abuse and Alcoholism binge model of ALD. Previous studies have shown that the two metabolites of ethanol consumption, malondialdhyde (MDA) and acetaldehyde (AA), combine to form MDA-AA (MAA) adducts, which have been correlated with the development and progression of ALD. In this study, murine PCLSs were incubated with ethanol and examined for the production of MAA adducts. PCLSs were homogenized, and homogenates were injected into C57BL/6 mice. PCLSs from control-, pair-, and ethanol-fed animals served as targets in in situ cytotoxic assays using primed T cells from mice hyperimmunized with control or ethanol-exposed PCLS homogenates. A CD45.1/CD45.2 passive-transfer model was used to determine whether T cells from the spleens of mice hyperimmunized with PCLS ethanol-exposed homogenates trafficked to the liver. PCLSs incubated with ethanol generated MAA-modified proteins in situ. Cytotoxic (CD8+) T cells from immunized mice killed naïve PCLSs from control- and pair-fed mice in vitro, a response that was blunted in PCLSs from ethanol-fed mice. Furthermore, CD45.1 CD8+ T cells from hyperimmunized mice trafficked to the liver but did not initiate liver damage. This study demonstrates that exposure to liver tissue damaged by ethanol mediates robust immune responses to well-characterized alcohol metabolites and native liver proteins in vitro. Moreover, although these proinflammatory T cells traffic to the liver, these responses appear to be dampened in vivo by locally acting pathways. NEW & NOTEWORTHY This study shows that the metabolites of ethanol and lipid breakdown produce malondialdehyde-acetaldehyde adducts in the precision-cut liver slice model system. Additionally, precision-cut liver slices exposed to ethanol and harboring malondialdehyde-acetaldehyde adducts generate liver-specific antibody and T cell responses in the spleens of naïve mice that could traffic to the liver.


Assuntos
Acetaldeído/imunologia , Autoimunidade , Fígado Gorduroso Alcoólico/imunologia , Hepatopatias Alcoólicas/imunologia , Fígado/imunologia , Malondialdeído/imunologia , Linfócitos T Citotóxicos/imunologia , Acetaldeído/metabolismo , Transferência Adotiva , Animais , Movimento Celular , Células Cultivadas , Modelos Animais de Doenças , Fígado Gorduroso Alcoólico/metabolismo , Feminino , Humanos , Técnicas In Vitro , Interleucina-6/imunologia , Interleucina-6/metabolismo , Antígenos Comuns de Leucócito/imunologia , Antígenos Comuns de Leucócito/metabolismo , Fígado/metabolismo , Hepatopatias Alcoólicas/metabolismo , Ativação Linfocitária , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , Fenótipo , Baço/imunologia , Baço/metabolismo , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/transplante
11.
Int J Mol Sci ; 19(12)2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30562944

RESUMO

Doxycycline (DOX), a derivative of tetracycline, is a broad-spectrum antibiotic that exhibits a number of therapeutic activities in addition to its antibacterial properties. For example, DOX has been used in the management of a number of diseases characterized by chronic inflammation. One potential mechanism by which DOX inhibits the progression of these diseases is by reducing oxidative stress, thereby inhibiting subsequent lipid peroxidation and inflammatory responses. Herein, we tested the hypothesis that DOX directly scavenges reactive oxygen species (ROS) and inhibits the formation of redox-mediated malondialdehyde-acetaldehyde (MAA) protein adducts. Using a cell-free system, we demonstrated that DOX scavenged reactive oxygen species (ROS) produced during the formation of MAA-adducts and inhibits the formation of MAA-protein adducts. To determine whether DOX scavenges specific ROS, we examined the ability of DOX to directly scavenge superoxide and hydrogen peroxide. Using electron paramagnetic resonance (EPR) spectroscopy, we found that DOX directly scavenged superoxide, but not hydrogen peroxide. Additionally, we found that DOX inhibits MAA-induced activation of Nrf2, a redox-sensitive transcription factor. Together, these findings demonstrate the under-recognized direct antioxidant property of DOX that may help to explain its therapeutic potential in the treatment of conditions characterized by chronic inflammation and increased oxidative stress.


Assuntos
Doxiciclina/química , Sequestradores de Radicais Livres/química , Sistema Livre de Células , Doxiciclina/farmacologia , Sequestradores de Radicais Livres/farmacologia , Células HEK293 , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Malondialdeído/química , Malondialdeído/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxidos/química , Superóxidos/metabolismo
13.
Rheumatology (Oxford) ; 56(10): 1794-1803, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28957552

RESUMO

Objective: To characterize the expression of malondialdehdye-acetaldehyde (MAA) adducts and anti-MAA antibody in articular tissues and serum of patients with RA. Methods: Paired sera and SF were examined from 29 RA and 13 OA patients. Anti-MAA antibody, RF, ACPA and total immunoglobulin were quantified. SF-serum measures were compared within and between disease groups. The presence and co-localization of MAA, citrulline and select leukocyte antigens in RA and OA synovial tissues were examined using immunohistochemistry. Results: Circulating and SF anti-MAA antibody concentrations were higher in RA vs OA by 1.5- to 5-fold. IgG (P < 0.001), IgM (P = 0.006) and IgA (P = 0.036) anti-MAA antibodies were higher in paired RA SF than serum, differences not observed for total immunoglobulin, RF or ACPA. In RA synovial tissues, co-localization of MAA with citrulline and CD19+ or CD27+ B cells was demonstrated and was much higher in magnitude than MAA or citrulline co-localization with T cells, monocytes, macrophages or dendritic cells (P < 0.01). Conclusion: Anti-MAA antibodies are present in higher concentrations in the RA joint compared with sera, a finding not observed for other disease-related autoantibodies. Co-localization of MAA and citrulline with mature B cells, coupled with the local enrichment of anti-MAA immune responses, implicates MAA-adduct formation in local autoantibody production.


Assuntos
Acetaldeído/imunologia , Artrite Reumatoide/imunologia , Autoanticorpos/análise , Articulações/imunologia , Malondialdeído/imunologia , Idoso , Artrite Reumatoide/sangue , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Osteoartrite/sangue , Osteoartrite/imunologia , Fator Reumatoide/sangue , Líquido Sinovial/imunologia
14.
Child Dev ; 88(4): 1284-1301, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27783400

RESUMO

Eye movements were recorded as 12-month-olds (n = 15), 4-year-olds (n = 17), and adults (n = 19) watched a 15-min video with sequences of shots conveying continuous motion. The central question was whether, and at what age, viewers anticipate the reappearance of objects following cuts to new shots. Adults were more likely than younger viewers to make anticipatory eye movements. Four-year-olds responded to transitions more slowly and tended to fixate the center of the screen. Infants' eye movement patterns reflected a tendency to react rather than anticipate. Findings are consistent with the hypothesis that adults integrate content across shots and understand how space is represented in edited video. Results are interpreted with respect to a developing understanding of film editing due to experience and cognitive maturation.


Assuntos
Antecipação Psicológica/fisiologia , Desenvolvimento Infantil/fisiologia , Movimentos Oculares/fisiologia , Percepção de Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Percepção Espacial/fisiologia , Adulto , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Adulto Jovem
15.
J Transl Med ; 14(1): 327, 2016 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-27884156

RESUMO

BACKGROUND: Myocardial recovery with left ventricular assist device (LVAD) therapy is highly variable and difficult to predict. Next generation ribonucleic acid (RNA) sequencing is an innovative, rapid, and quantitative approach to gene expression profiling in small amounts of tissue. Our primary goal was to identify baseline transcriptional profiles in non-ischemic cardiomyopathies that predict myocardial recovery in response to LVAD therapy. We also sought to verify transcriptional differences between failing and non-failing human hearts. METHODS: RNA was isolated from failing (n = 16) and non-failing (n = 8) human hearts. RNA from each patient was reverse transcribed and quantitatively sequenced on the personal genome machine (PGM) sequencer (Ion torrent) for 95 heart failure candidate genes. Coverage analysis as well as mapping the reads and alignment was done using the Ion Torrent Browser Suite™. Differential expression analyses were conducted by empirical analysis of digital gene expression data in R (edgeR) to identify differential expressed genes between failing and non-failing groups, and between responder and non-responder groups respectively. Targeted cardiac gene messenger RNA (mRNA) expression was analyzed in proportion to the total number of reads. Gene expression profiles from the PGM sequencer were validated by performing RNA sequencing (RNAseq) with the Illumina Hiseq2500 sequencing system. RESULTS: The failing sample population was 75% male with an average age of 50 and a left ventricular ejection fraction (LVEF) of 16%. Myosin light chain kinase (MYLK) and interleukin (IL)-6 genes expression were significantly higher in LVAD responders compared to non-responders. Thirty-six cardiac genes were expressed differentially between failing and non-failing hearts (23 decreased, 13 elevated). MYLK, Beta-1 adrenergic receptor (ADRB1) and myosin heavy chain (MYH)-6 expression were among those significantly decreased in failing hearts compared to non-failing hearts. Natriuretic peptide B (NPPB) and IL-6 were significantly elevated. Targeted gene expression profiles obtained from the Ion torrent PGM sequencer were consistent with those obtained from Illumina HiSeq2500 sequencing system. CONCLUSIONS: Heart failure is associated with a network of transcriptional changes involving contractile proteins, metabolism, adrenergic receptors, protein phosphorylation, and signaling factors. Myocardial MYLK and IL-6 expression are positively correlated with ejection fraction (EF) response to LVAD placement. Targeted RNA sequencing of myocardial gene expression can be utilized to predict responders to LVAD therapy and to better characterize transcriptional changes in human heart failure.


Assuntos
Perfilação da Expressão Gênica , Insuficiência Cardíaca/genética , Miocárdio/metabolismo , Análise de Sequência de RNA/métodos , Regulação para Baixo/genética , Feminino , Coração Auxiliar , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Transdução de Sinais/genética , Resultado do Tratamento , Regulação para Cima/genética
16.
J Vasc Surg ; 63(2): 477-84, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25724613

RESUMO

OBJECTIVE: Abdominal aortic aneurysm (AAA) is a pathologic dilation of the aorta. Inflammation of the aortic wall has been shown to be involved in AAA formation. Malondialdehyde-acetaldehyde (MAA) adducts are MAA/protein hybrids with immunogenic, proinflammatory, and profibrotic properties. Levels of MAA adducts are elevated in patients with coronary artery disease; however, the role of MAA adducts in AAA is unclear. We hypothesize that levels of circulating antibodies against MAA adducts are increased in patients with AAA. METHODS: Plasma samples were collected from mice and patients with AAA and control patients with atherosclerosis but not AAA. AAA was induced in mice by a standard CaCl2 protocol, with matching sham mice. Plasma levels of anti-MAA antibodies were quantified by enzyme-linked immunosorbent assay. RESULTS: Patients with AAA exhibited higher levels of immunoglobulin G and immunoglobulin A anti-MAA antibody subtypes (P = .049 and .026, respectively) compared with control patients. Conversely, immunoglobulin M anti-MAA antibodies in AAA patients were lower compared with control patients (P = .018). In CaCl2-treated mice, immunoglobulin G anti-MAA antibodies were elevated after AAA formation (P = .006). CONCLUSIONS: The pattern of anti-MAA antibodies is able to distinguish between patients with AAA and patients with atherosclerosis but no AAA. These results demonstrate that MAA adducts are associated with AAA and suggest that they may play a role in either initiating or propagating chronic inflammation in AAA.


Assuntos
Acetaldeído/imunologia , Aneurisma da Aorta Abdominal/diagnóstico , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Malondialdeído/imunologia , Acetaldeído/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Animais , Aneurisma da Aorta Abdominal/sangue , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/imunologia , Biomarcadores/sangue , Cloreto de Cálcio , Estudos de Casos e Controles , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Malondialdeído/análogos & derivados , Camundongos Endogâmicos C57BL , Valor Preditivo dos Testes , Regulação para Cima
18.
Rheumatology (Oxford) ; 54(9): 1587-95, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25854268

RESUMO

OBJECTIVE: To examine whether vascular calcifications on hand films in RA might aid in determining mortality risk. METHODS: Hand radiographs from 906 RA patients were scored as positive or negative for vascular calcifications. Patient characteristics associated with vascular calcifications were assessed using multivariable logistic regression, and associations with mortality were examined using Cox proportional hazards regression. Cytokines and multiplex ACPA were measured in both groups. RESULTS: A total of 99 patients (11%) demonstrated radiographic vascular calcifications. Factors independently associated with vascular calcifications included diabetes [odds ratio (OR) 2.85; 95% CI 1.43, 5.66], cardiovascular disease at enrolment (OR 2.48; 95% CI 1.01, 6.09), prednisone use (OR 1.90; 95% CI 1.25, 2.91), current smoking (OR 0.06; 95% CI 0.01, 0.23) and former smoking (OR 0.36; 95% CI 0.27, 0.48) vs never smoking. In cytokine and ACPA subtype analysis, IL-4 and anti-citrullinated apolipoprotein E were significantly increased in patients with vascular calcifications in fully adjusted multivariable models. After multivariable adjustment, vascular calcifications were associated with an increase in all-cause mortality (hazard ratio 1.41; 95% CI 1.12, 1.78; P = 0.004). CONCLUSION: Vascular calcifications on hand radiographs were independently associated with increased all-cause mortality in RA. Mechanisms underpinning the associations of IL-4 and select ACPA with vascular calcifications and their utility as biomarkers predictive of cardiovascular disease risk in RA merit further study.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Autoanticorpos/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Mãos/diagnóstico por imagem , Calcificação Vascular/complicações , Calcificação Vascular/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/sangue , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Biomarcadores/sangue , Feminino , Mãos/irrigação sanguínea , Humanos , Interleucina-4/sangue , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Peptídeos Cíclicos/imunologia , Radiografia , Fatores de Risco , Taxa de Sobrevida
19.
J Card Fail ; 21(10): 792-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25937146

RESUMO

BACKGROUND: Proven strategies to reduce right ventricular (RV) dysfunction after continuous-flow left ventricular assist device (CF-LVAD) implantation are lacking. We sought to evaluate the tolerability, feasibility, efficacy, and pharmacokinetics of inhaled milrinone (iMil) delivery after CF-LVAD implantation. METHODS AND RESULTS: We prospectively evaluated fixed-dose nebulized iMil delivered into a ventilator circuit for 24 hours in 10 postoperative CF-LVAD (Heartmate-II) patients. Tolerability (arrhythmias, hypotension, and hypersensitivity reaction), efficacy (hemodynamics), pharmacokinetics (plasma milrinone levels), and cost data were collected.Mean age was 56 ± 9 years, 90% were male, and mean INTERMACS profile was 2.5 ± 0.8. No new atrial arrhythmia events occurred, although 3 (30%) ventricular tachycardia (1 nonsustained, 2 sustained) events occurred. Sustained hypotension, drug hypersensitivity, death, or need for right ventricular assist device were not observed. Invasive mean pulmonary arterial pressure from baseline to during iMil therapy was improved (P = .017). Mean plasma milrinone levels (ng/mL) at baseline, and 1, 4, 8, 12, and 24 hours were 74.2 ± 35.4, 111.3 ± 70.9, 135.9 ± 41.5, 205.0 ± 86.7, 176.8 ± 61.3 187.6 ± 105.5, respectively. Reduced institutional cost was observed when iMil was compared with nitric oxide therapy over 24 hours ($165.29 vs $1,944.00, respectively). CONCLUSIONS: iMil delivery after CF-LVAD implantation was well tolerated, feasible, and demonstrated favorable hemodynamic, pharmacokinetic, and cost profiles. iMil therapy warrants further study in larger clinical trials.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/cirurgia , Coração Auxiliar/tendências , Milrinona/administração & dosagem , Administração por Inalação , Idoso , Análise Custo-Benefício , Feminino , Insuficiência Cardíaca/diagnóstico , Ventrículos do Coração , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Milrinona/economia , Cuidados Pós-Operatórios/economia , Cuidados Pós-Operatórios/métodos , Resultado do Tratamento , Vasodilatadores/administração & dosagem , Vasodilatadores/economia , Disfunção Ventricular Direita/prevenção & controle
20.
J Card Surg ; 30(2): 149-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25557136

RESUMO

A method, based on well-established trauma principles, is described for surgical management of serious intrathoracic bleeding complications that can occur during the extraction of pacemaker or defibrillator leads. Using this method, four patients who experienced rapid hemodynamic deterioration due to traumatic injury of the superior vena cava and its tributaries during defibrillator lead extraction underwent successful surgical repair. Perioperative preparation for high-risk lead extractions, management of major bleeding complications, and surgical repair techniques are discussed. Major bleeding complications can be managed effectively with this strategy leading to excellent overall success rates for extractions without mortality.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Remoção de Dispositivo/efeitos adversos , Hemorragia/etiologia , Hemorragia/cirurgia , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/cirurgia , Marca-Passo Artificial/efeitos adversos , Assistência Perioperatória , Doenças Torácicas/etiologia , Doenças Torácicas/cirurgia , Procedimentos Cirúrgicos Torácicos/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Resultado do Tratamento , Veia Cava Superior/lesões , Veia Cava Superior/cirurgia
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