Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 156
Filtrar
1.
J Vasc Interv Radiol ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38685471

RESUMO

PURPOSE: To compare the risk of hemorrhagic adverse events of transthoracic needle biopsy (TTNB) such as pulmonary hemorrhage and hemoptysis between patients with pulmonary hypertension (PH) and patients without PH. MATERIALS AND METHODS: Database search and citation review of search results were performed for studies reporting frequency of hemorrhagic adverse events of TTNB in adult patients with evidence of PH compared with that in patients undergoing the procedure without evidence of PH. Random-effects meta-analysis was performed for both rates of pulmonary hemorrhage and hemoptysis. RESULTS: A total of 5 studies (encompassing 6,250 patients who underwent 6,684 biopsies) were included. All studies were retrospective and used computed tomography (CT) or echocardiography for identification of signs of PH. Biopsy-related pulmonary hemorrhage was diagnosed radiographically, and postbiopsy hemoptysis was diagnosed by documentation in the medical record. There were no differences found between patients with evidence of PH and those without regarding rates of pulmonary hemorrhage (odds ratio [OR], 1.12 [95% confidence interval {CI}, 0.85-1.47] in studies that used CT to define PH, and OR, 0.88 [95% CI 0.56-1.39] in studies that used echocardiography to define PH). There were also no differences in the rates of hemoptysis (OR, 0.95 [95% CI, 0.46-1.97]). CONCLUSIONS: A systematic review and meta-analysis of the literature did not demonstrate that patients with imaging evidence of PH undergoing TTNB had an increased risk of hemorrhagic adverse events.

2.
Am J Respir Crit Care Med ; 208(3): 312-321, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37276608

RESUMO

Rationale: Predictors of adverse outcome in pulmonary hypertension (PH) are well established; however, data that inform survival are lacking. Objectives: We aim to identify clinical markers and therapeutic targets that inform the survival in PH. Methods: We included data from patients with elevated mean pulmonary artery pressure (mPAP) diagnosed by right heart catheterization in the U.S. Veterans Affairs system (October 1, 2006-September 30, 2018). Network medicine framework was used to subgroup patients when considering an N of 79 variables per patient. The results informed outcome analyses in the discovery cohort and a sex-balanced validation right heart catheterization cohort from Vanderbilt University (September 24, 1998-December 20, 2013). Measurements and Main Results: From an N of 4,737 complete case patients with mPAP of 19-24 mm Hg, there were 21 distinct subgroups (network modules) (all-cause mortality range = 15.9-61.2% per module). Pulmonary arterial compliance (PAC) drove patient assignment to modules characterized by increased survival. When modeled continuously in patients with mPAP ⩾19 mm Hg (N = 37,744; age, 67.2 yr [range = 61.7-73.8 yr]; 96.7% male; median follow-up time, 1,236 d [range = 570-1,971 d]), the adjusted all-cause mortality hazard ratio was <1.0 beginning at PAC ⩾3.0 ml/mm Hg and decreased progressively to ∼7 ml/mm Hg. A protective association between PAC ⩾3.0 ml/mm Hg and mortality was also observed in the validation cohort (N = 1,514; age, 60.2 yr [range = 49.2-69.1 yr]; 48.0% male; median follow-up time, 2,485 d [range = 671-3,580 d]). The association was strongest in patients with precapillary PH at the time of catheterization, in whom 41% (95% confidence interval, 0.55-0.62; P < 0.001) and 49% (95% confidence interval, 0.38-0.69; P < 0.001) improvements in survival were observed for PAC ⩾3.0 versus <3.0 ml/mm Hg in the discovery and validation cohorts, respectively. Conclusions: These data identify elevated PAC as an important parameter associated with survival in PH. Prospective studies are warranted that consider PAC ⩾3.0 ml/mm Hg as a therapeutic target to achieve through proven interventions.


Assuntos
Hipertensão Pulmonar , Artéria Pulmonar , Humanos , Masculino , Idoso , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Cateterismo Cardíaco , Modelos de Riscos Proporcionais , Hemodinâmica
3.
J Card Fail ; 28(1): 65-70, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34419597

RESUMO

BACKGROUND: A low right ventricular ejection fraction (RVEF) is a marker of poor outcomes in patients with heart failure with reduced ejection fraction (HFrEF). Beta-blockers improve outcomes in HFrEF, but whether this effect is modified by RVEF is unknown. METHODS AND RESULTS: Of the 2798 patients in Beta-Blocker Evaluation of Survival Trial (BEST), 2008 had data on baseline RVEF (mean 35%, median 34%). Patients were categorized into an RVEF of less than 35% (n = 1012) and an RVEF of 35% or greater (n = 996). We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) within each RVEF subgroup and formally tested for interactions between bucindolol and RVEF. The effect of bucindolol on all-cause mortality in 2008 patients with baseline RVEF (HR 0.88, 95% CI 0.75-1.02) is consistent with that in 2798 patients in the main trial (HR 0.90, 95% CI 0.78-1.02). Bucindolol use was associated with a lower risk of all-cause mortality in patients with an RVEF of 35% or greater (HR 0.70, 95% CI 0.55-0.89), but not in those with an RVEF of less than 35% (HR 1.02, 95% CI 0.83-1.24, P for interaction = .022). Similar variations were observed for cardiovascular mortality (P for interaction = .009) and sudden cardiac death (P for interaction = .018), but not for pump failure death (P for interaction = .371) or HF hospitalization (P for interaction = .251). CONCLUSIONS: The effect of bucindolol on mortality in patients with HFrEF was modified by the baseline RVEF. If these hypothesis-generating findings can be replicated using approved beta-blockers in contemporary patients with HFrEF, then RVEF may help to risk stratify patients with HFrEF for optimization of beta-blocker therapy.


Assuntos
Insuficiência Cardíaca , Antagonistas Adrenérgicos beta/uso terapêutico , Hospitalização , Humanos , Volume Sistólico , Função Ventricular Direita
4.
Sensors (Basel) ; 22(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35458944

RESUMO

Advances in information technology have harnessed the application of Quick Response (QR) codes in day-to-day activities, simplifying information exchange. QR codes are witnessed almost everywhere, on consumables, newspapers, information bulletins, etc. The simplicity of QR code creation and ease of scanning with free software have tremendously influenced their wide usage, and since QR codes place information on an object they are a tool for the IoT. Many healthcare IoT applications are deployed with QR codes for data-labeling and quick transfer of clinical data for rapid diagnosis. However, these codes can be duplicated and tampered with easily, attributed to open- source QR code generators and scanners. This paper presents a novel (n,n) secret-sharing scheme based on Nonnegative Matrix Factorization (NMF) for secured transfer of QR codes as multiple shares and their reconstruction with a regularized Super Resolution Convolutional Neural Network (SRCNN). This scheme is an alternative to the existing polynomial and visual cryptography-based schemes, exploiting NMF in part-based data representation and structural regularized SRCNN to capture the structural elements of the QR code in the super-resolved image. The experimental results and theoretical analyses show that the proposed method is a potential solution for secured exchange of QR codes with different error correction levels. The security of the proposed approach is evaluated with the difficulty in launching security attacks to recover and decode the secret QR code. The experimental results show that an adversary must try 258 additional combinations of shares and perform 3 × 288 additional computations, compared to a representative approach, to compromise the proposed system.


Assuntos
Algoritmos , Redes Neurais de Computação
5.
FASEB J ; 34(1): 1516-1531, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914698

RESUMO

Pseudomonas aeruginosa infections are increasingly multidrug resistant and cause healthcare-associated pneumonia, a major risk factor for acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Adenosine is a signaling nucleoside with potential opposing effects; adenosine can either protect against acute lung injury via adenosine receptors or cause lung injury via adenosine receptors or equilibrative nucleoside transporter (ENT)-dependent intracellular adenosine uptake. We hypothesized that blockade of intracellular adenosine uptake by inhibition of ENT1/2 would increase adenosine receptor signaling and protect against P. aeruginosa-induced acute lung injury. We observed that P. aeruginosa (strain: PA103) infection induced acute lung injury in C57BL/6 mice in a dose- and time-dependent manner. Using ENT1/2 pharmacological inhibitor, nitrobenzylthioinosine (NBTI), and ENT1-null mice, we demonstrated that ENT blockade elevated lung adenosine levels and significantly attenuated P. aeruginosa-induced acute lung injury, as assessed by lung wet-to-dry weight ratio, BAL protein levels, BAL inflammatory cell counts, pro-inflammatory cytokines, and pulmonary function (total lung volume, static lung compliance, tissue damping, and tissue elastance). Using both agonists and antagonists directed against adenosine receptors A2AR and A2BR, we further demonstrated that ENT1/2 blockade protected against P. aeruginosa -induced acute lung injury via activation of A2AR and A2BR. Additionally, ENT1/2 chemical inhibition and ENT1 knockout prevented P. aeruginosa-induced lung NLRP3 inflammasome activation. Finally, inhibition of inflammasome prevented P. aeruginosa-induced acute lung injury. Our results suggest that targeting ENT1/2 and NLRP3 inflammasome may be novel strategies for prevention and treatment of P. aeruginosa-induced pneumonia and subsequent ARDS.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Transportador Equilibrativo 1 de Nucleosídeo/antagonistas & inibidores , Transportador Equilibrativo 2 de Nucleosídeo/antagonistas & inibidores , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/metabolismo , Tioinosina/análogos & derivados , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/microbiologia , Lesão Pulmonar Aguda/patologia , Animais , Transportador Equilibrativo 1 de Nucleosídeo/metabolismo , Transportador Equilibrativo 2 de Nucleosídeo/metabolismo , Masculino , Camundongos , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/patologia , Tioinosina/farmacologia
6.
Arterioscler Thromb Vasc Biol ; 40(3): 714-732, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31996022

RESUMO

OBJECTIVE: Calcification of atherosclerotic plaque is traditionally associated with increased cardiovascular event risk; however, recent studies have found increased calcium density to be associated with more stable disease. 3-hydroxy-3-methylglutaryl coenzymeA reductase inhibitors or statins reduce cardiovascular events. Invasive clinical studies have found that statins alter both the lipid and calcium composition of plaque but the molecular mechanisms of statin-mediated effects on plaque calcium composition remain unclear. We recently defined a macrophage Rac (Ras-related C3 botulinum toxin substrate)-IL-1ß (interleukin-1 beta) signaling axis to be a key mechanism in promoting atherosclerotic calcification and sought to define the impact of statin therapy on this pathway. Approach and Results: Here, we demonstrate that statin therapy is independently associated with elevated coronary calcification in a high-risk patient population and that statins disrupt the complex between Rac1 and its inhibitor RhoGDI (Rho GDP-dissociation inhibitor), leading to increased active (GTP bound) Rac1 in primary monocytes/macrophages. Rac1 activation is prevented by rescue with the isoprenyl precursor geranylgeranyl diphosphate. Statin-treated macrophages exhibit increased activation of NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells), increased IL-1ß mRNA, and increased Rac1-dependent IL-1ß protein secretion in response to inflammasome stimulation. Using an animal model of calcific atherosclerosis, inclusion of statin in the atherogenic diet led to a myeloid Rac1-dependent increase in atherosclerotic calcification, which was associated with increased serum IL-1ß expression, increased plaque Rac1 activation, and increased plaque expression of the osteogenic markers, alkaline phosphatase and RUNX2 (Runt-related transcription factor 2). CONCLUSIONS: Statins are capable of increasing atherosclerotic calcification through disinhibition of a macrophage Rac1-IL-1ß signaling axis.


Assuntos
Aterosclerose/tratamento farmacológico , Atorvastatina/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Macrófagos/efeitos dos fármacos , Neuropeptídeos/metabolismo , Placa Aterosclerótica , Calcificação Vascular/enzimologia , Proteínas rac1 de Ligação ao GTP/metabolismo , Idoso , Animais , Aterosclerose/enzimologia , Aterosclerose/genética , Aterosclerose/patologia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos/enzimologia , Macrófagos/patologia , Masculino , Camundongos Knockout para ApoE , Neuropeptídeos/deficiência , Neuropeptídeos/genética , Prenilação , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Estudos Retrospectivos , Transdução de Sinais , Calcificação Vascular/genética , Calcificação Vascular/patologia , Proteínas rac1 de Ligação ao GTP/deficiência , Proteínas rac1 de Ligação ao GTP/genética , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/metabolismo
7.
J Pathol ; 252(4): 411-422, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32815166

RESUMO

Bronchopulmonary dysplasia (BPD), a chronic lung disease in premature infants, results from mechanical ventilation and hyperoxia, amongst other factors. Although most BPD survivors can be weaned from supplemental oxygen, many show evidence of cardiovascular sequelae in adulthood, including pulmonary hypertension and pulmonary vascular remodeling. Endothelial-mesenchymal transition (EndoMT) plays an important role in mediating vascular remodeling in idiopathic pulmonary arterial hypertension. Whether hyperoxic exposure, a known mediator of BPD in rodent models, causes EndoMT resulting in vascular remodeling and pulmonary hypertension remains unclear. We hypothesized that neonatal hyperoxic exposure causes EndoMT, leading to the development of pulmonary hypertension in adulthood. To test this hypothesis, newborn mice were exposed to hyperoxia and then allowed to recover in room air until adulthood. Neonatal hyperoxic exposure gradually caused pulmonary vascular and right ventricle remodeling as well as pulmonary hypertension. Male mice were more susceptible to developing pulmonary hypertension compared to female mice, when exposed to hyperoxia as newborns. Hyperoxic exposure induced EndoMT in mouse lungs as well as in cultured lung microvascular endothelial cells (LMVECs) isolated from neonatal mice and human fetal donors. This was augmented in cultured LMVECs from male donors compared to those from female donors. Using primary mouse LMVECs, hyperoxic exposure increased phosphorylation of both Smad2 and Smad3, but reduced Smad7 protein levels. Treatment with a selective TGF-ß inhibitor SB431542 blocked hyperoxia-induced EndoMT in vitro. Altogether, we show that neonatal hyperoxic exposure caused vascular remodeling and pulmonary hypertension in adulthood. This was associated with increased EndoMT. These novel observations provide mechanisms underlying hyperoxia-induced vascular remodeling and potential approaches to prevent BPD-associated pulmonary hypertension by targeting EndoMT. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Displasia Broncopulmonar/patologia , Células Endoteliais/patologia , Hiperóxia/patologia , Hipertensão Pulmonar/patologia , Pulmão/patologia , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/metabolismo , Células Endoteliais/metabolismo , Feminino , Hiperóxia/complicações , Hiperóxia/metabolismo , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Fosforilação , Fatores Sexuais , Proteínas Smad/metabolismo , Remodelação Vascular/fisiologia
8.
Sensors (Basel) ; 22(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35009569

RESUMO

In wireless communication, Fifth Generation (5G) Technology is a recent generation of mobile networks. In this paper, evaluations in the field of mobile communication technology are presented. In each evolution, multiple challenges were faced that were captured with the help of next-generation mobile networks. Among all the previously existing mobile networks, 5G provides a high-speed internet facility, anytime, anywhere, for everyone. 5G is slightly different due to its novel features such as interconnecting people, controlling devices, objects, and machines. 5G mobile system will bring diverse levels of performance and capability, which will serve as new user experiences and connect new enterprises. Therefore, it is essential to know where the enterprise can utilize the benefits of 5G. In this research article, it was observed that extensive research and analysis unfolds different aspects, namely, millimeter wave (mmWave), massive multiple-input and multiple-output (Massive-MIMO), small cell, mobile edge computing (MEC), beamforming, different antenna technology, etc. This article's main aim is to highlight some of the most recent enhancements made towards the 5G mobile system and discuss its future research objectives.


Assuntos
Comunicação , Tecnologia sem Fio , Humanos , Tecnologia
9.
Am J Respir Cell Mol Biol ; 63(5): 637-651, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32672471

RESUMO

Cigarette smoke (CS) exposure increases the risk for acute respiratory distress syndrome in humans and promotes alveolar-capillary barrier permeability and acute lung injury in animal models. However, the underlying mechanisms are not well understood. Mitochondrial fusion and fission are essential for mitochondrial homeostasis in health and disease. In this study, we hypothesized that CS caused endothelial injury via an imbalance of mitochondrial fusion and fission and resultant mitochondrial oxidative stress and dysfunction. We noted that CS altered mitochondrial morphology by shortening mitochondrial networks and causing perinuclear accumulation of damaged mitochondria in primary rat lung microvascular endothelial cells. We also found that CS increased mitochondrial fission likely by decreasing Drp1-S637 and increasing FIS1, Drp1-S616 phosphorylation, mitochondrial translocation, and tetramerization and reduced mitochondrial fusion likely by decreasing Mfn2 in lung microvascular endothelial cells and mouse lungs. CS also caused aberrant mitophagy, increased mitochondrial oxidative stress, and reduced mitochondrial respiration. An inhibitor of mitochondrial fission and a mitochondria-specific antioxidant prevented CS-induced increased endothelial barrier dysfunction and apoptosis. Our data suggest that excessive mitochondrial fission and resultant oxidative stress are essential mediators of CS-induced endothelial injury and that inhibition of mitochondrial fission and mitochondria-specific antioxidants may be useful therapeutic strategies for CS-induced endothelial injury and associated pulmonary diseases.


Assuntos
Células Endoteliais/patologia , Pulmão/patologia , Dinâmica Mitocondrial , Fumar/efeitos adversos , Animais , Apoptose , Permeabilidade Capilar , Respiração Celular , Dinaminas/metabolismo , Pulmão/irrigação sanguínea , Masculino , Camundongos , Microvasos/patologia , Mitocôndrias/patologia , Mitofagia , Modelos Biológicos , Estresse Oxidativo , Transporte Proteico , Ratos
10.
Blood ; 132(14): 1507-1518, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30104217

RESUMO

Adult T-cell leukemia lymphoma (ATLL) is a rare T cell neoplasm that is endemic in Japanese, Caribbean, and Latin American populations. Most North American ATLL patients are of Caribbean descent and are characterized by high rates of chemo-refractory disease and worse prognosis compared with Japanese ATLL. To determine genomic differences between these 2 cohorts, we performed targeted exon sequencing on 30 North American ATLL patients and compared the results with the Japanese ATLL cases. Although the frequency of TP53 mutations was comparable, the mutation frequency in epigenetic and histone modifying genes (57%) was significantly higher, whereas the mutation frequency in JAK/STAT and T-cell receptor/NF-κB pathway genes was significantly lower. The most common type of epigenetic mutation is that affecting EP300 (20%). As a category, epigenetic mutations were associated with adverse prognosis. Dissimilarities with the Japanese cases were also revealed by RNA sequencing analysis of 9 primary patient samples. ATLL samples with a mutated EP300 gene have decreased total and acetyl p53 protein and a transcriptional signature reminiscent of p53-mutated cancers. Most importantly, decitabine has highly selective single-agent activity in the EP300-mutated ATLL samples, suggesting that decitabine treatment induces a synthetic lethal phenotype in EP300-mutated ATLL cells. In conclusion, we demonstrate that North American ATLL has a distinct genomic landscape that is characterized by frequent epigenetic mutations that are targetable preclinically with DNA methyltransferase inhibitors.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Decitabina/uso terapêutico , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Proteína p300 Associada a E1A/genética , Epigênese Genética , Feminino , Humanos , Japão/epidemiologia , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Leucemia-Linfoma de Células T do Adulto/epidemiologia , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Prognóstico , Transcriptoma , Proteína Supressora de Tumor p53/genética , Estados Unidos/epidemiologia
11.
Circ Res ; 122(6): 864-876, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29437835

RESUMO

RATIONALE: Current methods assessing clinical risk because of exercise intolerance in patients with cardiopulmonary disease rely on a small subset of traditional variables. Alternative strategies incorporating the spectrum of factors underlying prognosis in at-risk patients may be useful clinically, but are lacking. OBJECTIVE: Use unbiased analyses to identify variables that correspond to clinical risk in patients with exercise intolerance. METHODS AND RESULTS: Data from 738 consecutive patients referred for invasive cardiopulmonary exercise testing at a single center (2011-2015) were analyzed retrospectively (derivation cohort). A correlation network of invasive cardiopulmonary exercise testing parameters was assembled using |r|>0.5. From an exercise network of 39 variables (ie, nodes) and 98 correlations (ie, edges) corresponding to P<9.5e-46 for each correlation, we focused on a subnetwork containing peak volume of oxygen consumption (pVo2) and 9 linked nodes. K-mean clustering based on these 10 variables identified 4 novel patient clusters characterized by significant differences in 44 of 45 exercise measurements (P<0.01). Compared with a probabilistic model, including 23 independent predictors of pVo2 and pVo2 itself, the network model was less redundant and identified clusters that were more distinct. Cluster assignment from the network model was predictive of subsequent clinical events. For example, a 4.3-fold (P<0.0001; 95% CI, 2.2-8.1) and 2.8-fold (P=0.0018; 95% CI, 1.5-5.2) increase in hazard for age- and pVo2-adjusted all-cause 3-year hospitalization, respectively, were observed between the highest versus lowest risk clusters. Using these data, we developed the first risk-stratification calculator for patients with exercise intolerance. When applying the risk calculator to patients in 2 independent invasive cardiopulmonary exercise testing cohorts (Boston and Graz, Austria), we observed a clinical risk profile that paralleled the derivation cohort. CONCLUSIONS: Network analyses were used to identify novel exercise groups and develop a point-of-care risk calculator. These data expand the range of useful clinical variables beyond pVo2 that predict hospitalization in patients with exercise intolerance.


Assuntos
Doenças Cardiovasculares/epidemiologia , Tolerância ao Exercício , Idoso , Teste de Esforço/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade
12.
Am J Respir Cell Mol Biol ; 58(5): 658-667, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29100477

RESUMO

Hyperproliferative endothelial cells (ECs) play an important role in the pathogenesis of pulmonary arterial hypertension (PAH). Anoctamin (Ano)-1, a calcium-activated chloride channel, can regulate cell proliferation and cell cycle in multiple cell types. However, the expression and function of Ano1 in the pulmonary endothelium is unknown. We examined whether Ano1 was expressed in pulmonary ECs and if altering Ano1 activity would affect EC survival. Expression and localization of Ano1 in rat lung microvascular ECs (RLMVECs) was assessed using immunoblot, immunofluorescence, and subcellular fractionation. Cell counts, flow cytometry, and caspase-3 activity were used to assess changes in cell number and apoptosis in response to the small molecule Ano1 activator, Eact. Changes in mitochondrial membrane potential and mitochondrial reactive oxygen species (mtROS) were assessed using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine, iodide (mitochondrial membrane potential dye) and mitochondrial ROS dye, respectively. Ano1 is expressed in RLMVECs and is enriched in the mitochondria. Activation of Ano1 with Eact reduced RLMVEC counts through increased apoptosis. Ano1 knockdown blocked the effects of Eact. Ano1 activation increased mtROS, reduced mitochondrial membrane potential, increased p38 phosphorylation, and induced release of apoptosis-inducing factor. mtROS inhibition attenuated Eact-mediated p38 phosphorylation. Pulmonary artery ECs isolated from patients with idiopathic PAH (IPAH) had higher expression of Ano1 and increased cell counts compared with control subjects. Eact treatment reduced cell counts in IPAH cells, which was associated with increased apoptosis. In summary, Ano1 is expressed in lung EC mitochondria. Activation of Ano1 promotes apoptosis of pulmonary ECs and human IPAH-pulmonary artery ECs, likely via increased mtROS and p38 phosphorylation, leading to apoptosis.


Assuntos
Anoctamina-1/agonistas , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Pulmão/irrigação sanguínea , Transdução de Sinais/efeitos dos fármacos , Tiazóis/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Anoctamina-1/metabolismo , Estudos de Casos e Controles , Hipóxia Celular , Células Cultivadas , Células Endoteliais/enzimologia , Células Endoteliais/patologia , Hipertensão Pulmonar Primária Familiar/enzimologia , Hipertensão Pulmonar Primária Familiar/patologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/patologia , Proteínas de Neoplasias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
13.
J Physiol ; 596(5): 827-855, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29313986

RESUMO

KEY POINTS: Abnormal mitochondrial morphology and function in cardiomyocytes are frequently observed under persistent Gq protein-coupled receptor (Gq PCR) stimulation. Cardiac signalling mechanisms for regulating mitochondrial morphology and function under pathophysiological conditions in the heart are still poorly understood. We demonstrate that a downstream kinase of Gq PCR, protein kinase D (PKD) induces mitochondrial fragmentation via phosphorylation of dynamin-like protein 1 (DLP1), a mitochondrial fission protein. The fragmented mitochondria enhance reactive oxygen species generation and permeability transition pore opening in mitochondria, which initiate apoptotic signalling activation. This study identifies a novel PKD-specific substrate in cardiac mitochondria and uncovers the role of PKD on cardiac mitochondria, with special emphasis on the molecular mechanism(s) underlying mitochondrial injury with abnormal mitochondrial morphology under persistent Gq PCR stimulation. These findings provide new insights into the molecular basis of cardiac mitochondrial physiology and pathophysiology, linking Gq PCR signalling with the regulation of mitochondrial morphology and function. ABSTRACT: Regulation of mitochondrial morphology is crucial for the maintenance of physiological functions in many cell types including cardiomyocytes. Small and fragmented mitochondria are frequently observed in pathological conditions, but it is still unclear which cardiac signalling pathway is responsible for regulating the abnormal mitochondrial morphology in cardiomyocytes. Here we demonstrate that a downstream kinase of Gq protein-coupled receptor (Gq PCR) signalling, protein kinase D (PKD), mediates pathophysiological modifications in mitochondrial morphology and function, which consequently contribute to the activation of apoptotic signalling. We show that Gq PCR stimulation induced by α1 -adrenergic stimulation mediates mitochondrial fragmentation in a fission- and PKD-dependent manner in H9c2 cardiac myoblasts and rat neonatal cardiomyocytes. Upon Gq PCR stimulation, PKD translocates from the cytoplasm to the outer mitochondrial membrane (OMM) and phosphorylates a mitochondrial fission protein, dynamin-like protein 1 (DLP1), at S637. PKD-dependent phosphorylation of DLP1 initiates DLP1 association with the OMM, which then enhances mitochondrial fragmentation, mitochondrial superoxide generation, mitochondrial permeability transition pore opening and apoptotic signalling. Finally, we demonstrate that DLP1 phosphorylation at S637 by PKD occurs in vivo using ventricular tissues from transgenic mice with cardiac-specific overexpression of constitutively active Gαq protein. In conclusion, Gq PCR-PKD signalling induces mitochondrial fragmentation and dysfunction via PKD-dependent DLP1 phosphorylation in cardiomyocytes. This study is the first to identify a novel PKD-specific substrate, DLP1 in mitochondria, as well as the functional role of PKD in cardiac mitochondria. Elucidation of these molecular mechanisms by which PKD-dependent enhanced fission mediates cardiac mitochondrial injury will provide novel insight into the relationship among mitochondrial form, function and Gq PCR signalling.


Assuntos
Dinaminas/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Mitocôndrias/patologia , Dinâmica Mitocondrial , Miócitos Cardíacos/patologia , Proteína Quinase C/metabolismo , Animais , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial , Poro de Transição de Permeabilidade Mitocondrial , Miócitos Cardíacos/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
14.
J Biol Chem ; 292(3): 837-846, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-27909050

RESUMO

Clear cell renal cell carcinoma (CCRCC) is an incurable malignancy in advanced stages and needs newer therapeutic targets. Transcriptomic analysis of CCRCCs and matched microdissected renal tubular controls revealed overexpression of NOTCH ligands and receptors in tumor tissues. Examination of the TCGA RNA-seq data set also revealed widespread activation of NOTCH pathway in a large cohort of CCRCC samples. Samples with NOTCH pathway activation were also clinically distinct and were associated with better overall survival. Parallel DNA methylation and copy number analysis demonstrated that both genetic and epigenetic alterations led to NOTCH pathway activation in CCRCC. NOTCH ligand JAGGED1 was overexpressed and associated with loss of CpG methylation of H3K4me1-associated enhancer regions. JAGGED2 was also overexpressed and associated with gene amplification in distinct CCRCC samples. Transgenic expression of intracellular NOTCH1 in mice with tubule-specific deletion of VHL led to dysplastic hyperproliferation of tubular epithelial cells, confirming the procarcinogenic role of NOTCH in vivo Alteration of cell cycle pathways was seen in murine renal tubular cells with NOTCH overexpression, and molecular similarity to human tumors was observed, demonstrating that human CCRCC recapitulates features and gene expression changes observed in mice with transgenic overexpression of the Notch intracellular domain. Treatment with the γ-secretase inhibitor LY3039478 led to inhibition of CCRCC cells in vitro and in vivo In summary, these data reveal the mechanistic basis of NOTCH pathway activation in CCRCC and demonstrate this pathway to a potential therapeutic target.


Assuntos
Neoplasias Renais/metabolismo , Proteínas de Neoplasias/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Carcinoma de Células Renais , Ilhas de CpG , Metilação de DNA , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Feminino , Humanos , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Inibidores de Proteases/farmacologia , Receptor Notch1/genética
15.
Sensors (Basel) ; 18(6)2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29890704

RESUMO

The Internet of Things (IoT) utilizes algorithms to facilitate intelligent applications across cities in the form of smart-urban projects. As the majority of devices in IoT are battery operated, their applications should be facilitated with a low-power communication setup. Such facility is possible through the Low-Power Wide-Area Network (LPWAN), but at a constrained bit rate. For long-range communication over LPWAN, several approaches and protocols are adopted. One such protocol is the Long-Range Wide Area Network (LoRaWAN), which is a media access layer protocol for long-range communication between the devices and the application servers via LPWAN gateways. However, LoRaWAN comes with fewer security features as a much-secured protocol consumes more battery because of the exorbitant computational overheads. The standard protocol fails to support end-to-end security and perfect forward secrecy while being vulnerable to the replay attack that makes LoRaWAN limited in supporting applications where security (especially end-to-end security) is important. Motivated by this, an enhanced LoRaWAN security protocol is proposed, which not only provides the basic functions of connectivity between the application server and the end device, but additionally averts these listed security issues. The proposed protocol is developed with two options, the Default Option (DO) and the Security-Enhanced Option (SEO). The protocol is validated through Burrows⁻Abadi⁻Needham (BAN) logic and the Automated Validation of Internet Security Protocols and Applications (AVISPA) tool. The proposed protocol is also analyzed for overheads through system-based and low-power device-based evaluations. Further, a case study on a smart factory-enabled parking system is considered for its practical application. The results, in terms of network latency with reliability fitting and signaling overheads, show paramount improvements and better performance for the proposed protocol compared with the two handshake options, Pre-Shared Key (PSK) and Elliptic Curve Cryptography (ECC), of Datagram Transport Layer Security (DTLS).

16.
Am J Respir Cell Mol Biol ; 57(6): 662-673, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28763253

RESUMO

Inhalation of acrolein, a highly reactive aldehyde, causes lung edema. The underlying mechanism is poorly understood and there is no effective treatment. In this study, we demonstrated that acrolein not only dose-dependently induced lung edema but also promoted LPS-induced acute lung injury. Importantly, acrolein-induced lung injury was prevented and rescued by Alda-1, an activator of mitochondrial aldehyde dehydrogenase 2. Acrolein also dose-dependently increased monolayer permeability, disrupted adherens junctions and focal adhesion complexes, and caused intercellular gap formation in primary cultured lung microvascular endothelial cells (LMVECs). These effects were attenuated by Alda-1 and the antioxidant N-acetylcysteine, but not by the NADPH inhibitor apocynin. Furthermore, acrolein inhibited AMP-activated protein kinase (AMPK) and increased mitochondrial reactive oxygen species levels in LMVECs-effects that were associated with impaired mitochondrial respiration. AMPK total protein levels were also reduced in lung tissue of mice and LMVECs exposed to acrolein. Activation of AMPK with 5-aminoimidazole-4-carboxamide-1-ß-4-ribofuranoside blunted an acrolein-induced increase in endothelial monolayer permeability, but not mitochondrial oxidative stress or inhibition of mitochondrial respiration. Our results suggest that acrolein-induced mitochondrial dysfunction may not contribute to endothelial barrier dysfunction. We speculate that detoxification of acrolein by Alda-1 and activation of AMPK may be novel approaches to prevent and treat acrolein-associated acute lung injury, which may occur after smoke inhalation.


Assuntos
Acroleína/efeitos adversos , Lesão Pulmonar Aguda/tratamento farmacológico , Benzamidas/farmacologia , Benzodioxóis/farmacologia , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Acetilcisteína/farmacologia , Acroleína/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Células Endoteliais/patologia , Endotélio Vascular/patologia , Ativação Enzimática/efeitos dos fármacos , Masculino , Camundongos , Mitocôndrias/patologia , Consumo de Oxigênio/efeitos dos fármacos
17.
Circulation ; 133(13): 1240-8, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26873944

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is associated with increased morbidity across the cardiopulmonary disease spectrum. Based primarily on expert consensus opinion, PH is defined by a mean pulmonary artery pressure (mPAP) ≥25 mm Hg. Although mPAP levels below this threshold are common among populations at risk for PH, the relevance of mPAP <25 mm Hg to clinical outcome is unknown. METHODS AND RESULTS: We analyzed retrospectively all US veterans undergoing right heart catheterization (2007-2012) in the Veterans Affairs healthcare system (n=21,727; 908-day median follow-up). Cox proportional hazards models were used to evaluate the association between mPAP and outcomes of all-cause mortality and hospitalization, adjusted for clinical covariates. When treating mPAP as a continuous variable, the mortality hazard increased beginning at 19 mm Hg (hazard ratio [HR]=1.183; 95% confidence interval [CI], 1.004-1.393) relative to 10 mm Hg. Therefore, patients were stratified into 3 groups: (1) referent (≤18 mm Hg; n=4,207); (2) borderline PH (19-24 mm Hg; n=5,030); and (3) PH (≥25 mm Hg; n=12,490). The adjusted mortality hazard was increased for borderline PH (HR=1.23; 95% CI, 1.12-1.36; P<0.0001) and PH (HR=2.16; 95% CI, 1.96-2.38; P<0.0001) compared with the referent group. The adjusted hazard for hospitalization was also increased in borderline PH (HR=1.07; 95% CI, 1.01-1.12; P=0.0149) and PH (HR=1.15; 95% CI, 1.09-1.22; P<0.0001). The borderline PH cohort remained at increased risk for mortality after excluding the following high-risk subgroups: (1) patients with pulmonary artery wedge pressure >15 mm Hg; (2) pulmonary vascular resistance ≥3.0 Wood units; or (3) inpatient status at the time of right heart catheterization. CONCLUSIONS: These data illustrate a continuum of risk according to mPAP level and that borderline PH is associated with increased mortality and hospitalization. Future investigations are needed to test the generalizability of our findings to other populations and study the effect of treatment on outcome in borderline PH.


Assuntos
Hospitalização/tendências , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/mortalidade , Relatório de Pesquisa/tendências , United States Department of Veterans Affairs/tendências , Veteranos , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/mortalidade , Cateterismo Cardíaco/tendências , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Estudos Retrospectivos , Estados Unidos/epidemiologia
18.
Am J Physiol Lung Cell Mol Physiol ; 312(5): L748-L759, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28258105

RESUMO

Right ventricular (RV) dysfunction is associated with numerous smoking-related illnesses, including chronic obstructive pulmonary disease (COPD), in which it is present even in the absence of pulmonary hypertension. It is unknown whether exposure to cigarette smoke (CS) has direct effects on RV function and cardiac fibroblast (CF) proliferation or collagen synthesis. In this study, we evaluated cardiac function and fibrosis in mice exposed to CS and determined mechanisms of smoke-induced changes in CF signaling and fibrosis. AKR mice were exposed to CS for 6 wk followed by echocardiography and evaluation of cardiac hypertrophy, collagen content, and pulmonary muscularization. Proliferation and collagen content were evaluated in primary isolated rat CFs exposed to CS extract (CSE) or nicotine. Markers of cell proliferation, fibrosis, and proliferative signaling were determined by immunoblot or Sircol collagen assay. Mice exposed to CS had significantly decreased RV function, as determined by tricuspid annular plane systolic excursion. There were no changes in left ventricular parameters. RV collagen content was significantly elevated, but there was no change in RV hypertrophy or pulmonary vascular muscularization. CSE directly increased CF proliferation and collagen content in CF. Nicotine alone reproduced these effects. CSE and nicotine-induced fibroblast proliferation and collagen content were mediated through α7 nicotinic acetylcholine receptors and were dependent on PKC-α, PKC-δ, and reduced p38-MAPK phosphorylation. CS and nicotine have direct effects on CFs to induce proliferation and fibrosis, which may negatively affect right heart function.


Assuntos
Fibroblastos/metabolismo , Fibroblastos/patologia , Ventrículos do Coração/patologia , Miocárdio/patologia , Fumar/efeitos adversos , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Hipertrofia Ventricular Direita/complicações , Hipertrofia Ventricular Direita/diagnóstico por imagem , Hipertrofia Ventricular Direita/patologia , Hipertrofia Ventricular Direita/fisiopatologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos Endogâmicos AKR , Nicotina/farmacologia , Fosforilação/efeitos dos fármacos , Proteína Quinase C-alfa/metabolismo , Proteína Quinase C-delta/metabolismo , Ratos Sprague-Dawley , Remodelação Vascular/efeitos dos fármacos , Disfunção Ventricular Direita/complicações , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/patologia , Disfunção Ventricular Direita/fisiopatologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Echocardiography ; 33(5): 749-55, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26680507

RESUMO

BACKGROUND: A subset of patients with severe aortic stenosis (AS) have lower stroke volumes and valve gradients despite a normal left ventricular ejection fraction (LVEF), referred to as paradoxical low-flow AS (PLF AS). However, the role of right ventricular (RV) function in patients with severe AS and preserved LVEF is not known. We hypothesized that right ventricular function is associated with left ventricular stroke volume in patients with severe AS and preserved LVEF. METHODS: From an echocardiographic database, we retrospectively identified 102 patients with an indexed aortic valve area ≤0.6 cm(2) /m(2) and LVEF ≥ 50%. We used univariate and multivariate linear regression analysis to assess the association between aortic valve stroke volume index (SVi) and right ventricular systolic function as measured by tricuspid annular plane systolic excursion (TAPSE) and by right ventricular fractional area change (FAC). RESULTS: Our population was 98% male with mean age 77.4 ± 9.3 years and mean SVi of 36.1 ± 7.9 mL/m(2) . Forty-four patients (43%) met criteria for PLF AS. TAPSE and FAC were positively associated with SVi in both univariate and multivariate regression analysis after correcting for left ventricular variables (ß coefficient - TAPSE (cm): 4.59 ± 1.3, P = 0.001; FAC (%): 0.19 ± 0.08, P = 0.014). Additionally, PLF AS patients had significantly lower mean TAPSE and lower mean FAC when compared dichotomously to normal flow AS patients (P < 0.05). CONCLUSIONS: Right ventricular systolic function assessed by TAPSE and FAC is significantly related to aortic valve flow in patients with severe AS and preserved LVEF.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Volume Sistólico , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Esquerda , Idoso , Estenose da Valva Aórtica/complicações , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Disfunção Ventricular Direita/etiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA