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1.
JAMA Cardiol ; 6(7): 745-752, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662103

RESUMO

Importance: The major North American professional sports leagues were among the first to return to full-scale sport activity during the coronavirus disease 2019 (COVID-19) pandemic. Given the unknown incidence of adverse cardiac sequelae after COVID-19 infection in athletes, these leagues implemented a conservative return-to-play (RTP) cardiac testing program aligned with American College of Cardiology recommendations for all athletes testing positive for COVID-19. Objective: To assess the prevalence of detectable inflammatory heart disease in professional athletes with prior COVID-19 infection, using current RTP screening recommendations. Design, Setting, and Participants: This cross-sectional study reviewed RTP cardiac testing performed between May and October 2020 on professional athletes who had tested positive for COVID-19. The professional sports leagues (Major League Soccer, Major League Baseball, National Hockey League, National Football League, and the men's and women's National Basketball Association) implemented mandatory cardiac screening requirements for all players who had tested positive for COVID-19 prior to resumption of team-organized sports activities. Exposures: Troponin testing, electrocardiography (ECG), and resting echocardiography were performed after a positive COVID-19 test result. Interleague, deidentified cardiac data were pooled for collective analysis. Those with abnormal screening test results were referred for additional testing, including cardiac magnetic resonance imaging and/or stress echocardiography. Main Outcomes and Measures: The prevalence of abnormal RTP test results potentially representing COVID-19-associated cardiac injury, and results and outcomes of additional testing generated by the initial screening process. Results: The study included 789 professional athletes (mean [SD] age, 25 [3] years; 777 men [98.5%]). A total of 460 athletes (58.3%) had prior symptomatic COVID-19 illness, and 329 (41.7%) were asymptomatic or paucisymptomatic (minimally symptomatic). Testing was performed a mean (SD) of 19 (17) days (range, 3-156 days) after a positive test result. Abnormal screening results were identified in 30 athletes (3.8%; troponin, 6 athletes [0.8%]; ECG, 10 athletes [1.3%]; echocardiography, 20 athletes [2.5%]), necessitating additional testing; 5 athletes (0.6%) ultimately had cardiac magnetic resonance imaging findings suggesting inflammatory heart disease (myocarditis, 3; pericarditis, 2) that resulted in restriction from play. No adverse cardiac events occurred in athletes who underwent cardiac screening and resumed professional sport participation. Conclusions and Relevance: This study provides large-scale data assessing the prevalence of relevant COVID-19-associated cardiac pathology with implementation of current RTP screening recommendations. While long-term follow-up is ongoing, few cases of inflammatory heart disease have been detected, and a safe return to professional sports activity has thus far been achieved.


Assuntos
Atletas/estatística & dados numéricos , COVID-19/epidemiologia , Cardiopatias/epidemiologia , Programas de Rastreamento/métodos , Adulto , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Volta ao Esporte , SARS-CoV-2 , Estados Unidos/epidemiologia , Adulto Jovem
2.
Histopathology ; 79(1): 67-76, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33432658

RESUMO

AIMS: Idiopathic pulmonary fibrosis (IPF) is a genetically mediated, age-associated, progressive form of pulmonary fibrosis characterised pathologically by a usual interstitial pneumonia (UIP) pattern of fibrosis. The UIP pattern is also found in pulmonary fibrosis attributable to clinical diagnoses other than IPF (non-IPF UIP), whose clinical course is similarly poor, suggesting common molecular drivers. This study investigates whether IPF and non-IPF UIP lungs similarly express markers of telomere dysfunction and senescence. METHODS AND RESULTS: To test whether patients with IPF and non-IPF UIP share molecular drivers, lung tissues from 169 IPF patients and 57 non-IPF UIP patients were histopathologically and molecularly compared. Histopathological changes in both IPF and non-IPF UIP patients included temporal heterogeneity, microscopic honeycombing, fibroblast foci, and dense collagen fibrosis. Non-IPF UIP lungs were more likely to have lymphocytic infiltration, non-caseating granulomas, airway-centred inflammation, or small airways disease. Telomeres were shorter in alveolar type II (AECII) cells of both IPF and non-IPF UIP lungs than in those of age-similar, unused donor, controls. Levels of molecular markers of senescence (p16 and p21) were elevated in lysates of IPF and non-IPF UIP lungs. Immunostaining localised expression of these proteins to AECII cells. The mucin 5B (MUC5B) gene promoter variant minor allele frequency was similar between IPF and non-IPF UIP patients, and MUC5B expression was similar in IPF and non-IPF UIP lungs. CONCLUSIONS: Molecular markers of telomere dysfunction and senescence are pathologically expressed in both IPF and non-IPF UIP lungs. These findings suggest that common molecular drivers may contribute to the pathogenesis of UIP-associated pulmonary fibrosis, regardless of the clinical diagnosis.


Assuntos
Biomarcadores/análise , Senescência Celular/fisiologia , Fibrose Pulmonar Idiopática/patologia , Telômero/patologia , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
J Card Surg ; 35(7): 1740-1742, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32484973

RESUMO

BACKGROUND AND AIMS: Lipomatous hypertrophy of the interatrial septum is an uncommon type of cardiac adipose tumor. It is extremely rare for these lesions to be located in the interventricular septum. METHODS: We report this case of incidentally diagnosed lipomatous hypertrophy of the interventricular septum with right ventricular outflow obstruction which caused minimal symptoms and Wolff-Parkinson-White pattern on EKG. CONCLUSION: We also discuss the diagnosis and management of this condition.


Assuntos
Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirurgia , Lipoma/diagnóstico , Lipoma/cirurgia , Neoplasias Lipomatosas/diagnóstico , Neoplasias Lipomatosas/cirurgia , Septo Interventricular/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , Ecocardiografia Transesofagiana , Eletrocardiografia , Feminino , Neoplasias Cardíacas/patologia , Humanos , Hipertrofia , Lipoma/patologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neoplasias Lipomatosas/patologia , Resultado do Tratamento , Septo Interventricular/patologia , Síndrome de Wolff-Parkinson-White
4.
N Engl J Med ; 382(24): 2327-2336, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32275812

RESUMO

BACKGROUND: Remdesivir, a nucleotide analogue prodrug that inhibits viral RNA polymerases, has shown in vitro activity against SARS-CoV-2. METHODS: We provided remdesivir on a compassionate-use basis to patients hospitalized with Covid-19, the illness caused by infection with SARS-CoV-2. Patients were those with confirmed SARS-CoV-2 infection who had an oxygen saturation of 94% or less while they were breathing ambient air or who were receiving oxygen support. Patients received a 10-day course of remdesivir, consisting of 200 mg administered intravenously on day 1, followed by 100 mg daily for the remaining 9 days of treatment. This report is based on data from patients who received remdesivir during the period from January 25, 2020, through March 7, 2020, and have clinical data for at least 1 subsequent day. RESULTS: Of the 61 patients who received at least one dose of remdesivir, data from 8 could not be analyzed (including 7 patients with no post-treatment data and 1 with a dosing error). Of the 53 patients whose data were analyzed, 22 were in the United States, 22 in Europe or Canada, and 9 in Japan. At baseline, 30 patients (57%) were receiving mechanical ventilation and 4 (8%) were receiving extracorporeal membrane oxygenation. During a median follow-up of 18 days, 36 patients (68%) had an improvement in oxygen-support class, including 17 of 30 patients (57%) receiving mechanical ventilation who were extubated. A total of 25 patients (47%) were discharged, and 7 patients (13%) died; mortality was 18% (6 of 34) among patients receiving invasive ventilation and 5% (1 of 19) among those not receiving invasive ventilation. CONCLUSIONS: In this cohort of patients hospitalized for severe Covid-19 who were treated with compassionate-use remdesivir, clinical improvement was observed in 36 of 53 patients (68%). Measurement of efficacy will require ongoing randomized, placebo-controlled trials of remdesivir therapy. (Funded by Gilead Sciences.).


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , Ensaios de Uso Compassivo , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/uso terapêutico , Administração Intravenosa , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina/efeitos adversos , Alanina/uso terapêutico , Antivirais/efeitos adversos , Betacoronavirus , COVID-19 , Canadá , Infecções por Coronavirus/mortalidade , Europa (Continente) , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/mortalidade , Respiração Artificial , SARS-CoV-2 , Estados Unidos , Adulto Jovem , Tratamento Farmacológico da COVID-19
5.
J Card Surg ; 34(12): 1608-1616, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31557360

RESUMO

BACKGROUND: Coronary artery fistula is a rare anomaly of the coronary arteries which results from an abnormal connection between a coronary artery with a cardiac chamber or vessel. Coronary steal phenomenon can lead to functional ischemia of the myocardium. The condition has been described extensively, however, the modalities for diagnosing this condition continue to advance. METHODS: This review summarizes the approach to managing this uncommon condition. RESULTS: We discuss the various surgical options, including the technique involved in treating specific types of fistulas. CONCLUSION: We also review minimally-invasive options and trans-catheter closure along with indications for use of the different modalities.


Assuntos
Doença da Artéria Coronariana , Fístula Vascular , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/cirurgia , Humanos , Fístula Vascular/diagnóstico , Fístula Vascular/etiologia , Fístula Vascular/cirurgia
6.
Histopathology ; 74(2): 341-349, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30152895

RESUMO

AIMS: The objective of this study was to quantify the impact of pirfenidone or nintedanib treatment on lung histopathology and molecular mediators of fibrosis in patients with idiopathic pulmonary fibrosis (IPF). METHODS AND RESULTS: We collected lung tissue from IPF patients at the time of lung transplantation. Histopathological changes were quantified using a blinded scoring method. Proteins associated with senescence or active TGF-ß were quantified in lung tissues by immunoblot and immunostaining. Histopathological quantification showed similar amounts of dense collagen fibrosis, fibroblast foci and alveolar macrophages in untreated or pirfenidone- or nintedanib-treated IPF patients. There was less diffuse alveolar damage and organising pneumonia in pirfenidone-treated IPF patients. Lungs of nintedanib-treated patients had a trend towards less lymphocytic interstitial infiltration. There was no difference in expression of p-SMAD3, p21 or p16 in the lungs of untreated, pirfenidone- or nintedanib-treated IPF patients. Alveolar epithelial cells, but not fibroblast foci, were immunoreactive to p16. Pirfenidone or nintedanib treatment did not inhibit activation of senescence programming in cultured lung epithelial cells mediated by hydrogen peroxide. CONCLUSION: Pirfenidone and nintedanib do not modulate expression of senescence markers, levels of p-SMAD3 or the amount of fibrosis in IPF lungs. Treated patients have less histopathological evidence of acute lung injury at the time of lung transplantation.


Assuntos
Células Epiteliais Alveolares/patologia , Fibrose Pulmonar Idiopática/patologia , Indóis/farmacologia , Pulmão/patologia , Piridonas/farmacologia , Idoso , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Linhagem Celular Tumoral , Feminino , Fibroblastos/patologia , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/metabolismo , Indóis/uso terapêutico , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Pessoa de Meia-Idade , Piridonas/uso terapêutico
7.
JAMA Neurol ; 75(8): 947-955, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29710329

RESUMO

Importance: Identifying infectious causes of subacute or chronic meningitis can be challenging. Enhanced, unbiased diagnostic approaches are needed. Objective: To present a case series of patients with diagnostically challenging subacute or chronic meningitis using metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) supported by a statistical framework generated from mNGS of control samples from the environment and from patients who were noninfectious. Design, Setting, and Participants: In this case series, mNGS data obtained from the CSF of 94 patients with noninfectious neuroinflammatory disorders and from 24 water and reagent control samples were used to develop and implement a weighted scoring metric based on z scores at the species and genus levels for both nucleotide and protein alignments to prioritize and rank the mNGS results. Total RNA was extracted for mNGS from the CSF of 7 participants with subacute or chronic meningitis who were recruited between September 2013 and March 2017 as part of a multicenter study of mNGS pathogen discovery among patients with suspected neuroinflammatory conditions. The neurologic infections identified by mNGS in these 7 participants represented a diverse array of pathogens. The patients were referred from the University of California, San Francisco Medical Center (n = 2), Zuckerberg San Francisco General Hospital and Trauma Center (n = 2), Cleveland Clinic (n = 1), University of Washington (n = 1), and Kaiser Permanente (n = 1). A weighted z score was used to filter out environmental contaminants and facilitate efficient data triage and analysis. Main Outcomes and Measures: Pathogens identified by mNGS and the ability of a statistical model to prioritize, rank, and simplify mNGS results. Results: The 7 participants ranged in age from 10 to 55 years, and 3 (43%) were female. A parasitic worm (Taenia solium, in 2 participants), a virus (HIV-1), and 4 fungi (Cryptococcus neoformans, Aspergillus oryzae, Histoplasma capsulatum, and Candida dubliniensis) were identified among the 7 participants by using mNGS. Evaluating mNGS data with a weighted z score-based scoring algorithm reduced the reported microbial taxa by a mean of 87% (range, 41%-99%) when taxa with a combined score of 0 or less were removed, effectively separating bona fide pathogen sequences from spurious environmental sequences so that, in each case, the causative pathogen was found within the top 2 scoring microbes identified using the algorithm. Conclusions and Relevance: Diverse microbial pathogens were identified by mNGS in the CSF of patients with diagnostically challenging subacute or chronic meningitis, including a case of subarachnoid neurocysticercosis that defied diagnosis for 1 year, the first reported case of CNS vasculitis caused by Aspergillus oryzae, and the fourth reported case of C dubliniensis meningitis. Prioritizing metagenomic data with a scoring algorithm greatly clarified data interpretation and highlighted the problem of attributing biological significance to organisms present in control samples used for metagenomic sequencing studies.


Assuntos
Meningite/diagnóstico , Metagenoma/genética , Adolescente , Adulto , Animais , Aspergillus oryzae/genética , Candida/genética , Candidíase/líquido cefalorraquidiano , Candidíase/diagnóstico , Criança , Doença Crônica , Cryptococcus neoformans/genética , Feminino , Infecções por HIV/líquido cefalorraquidiano , Infecções por HIV/diagnóstico , HIV-1/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Histoplasma/genética , Histoplasmose/líquido cefalorraquidiano , Histoplasmose/diagnóstico , Humanos , Masculino , Meningite/líquido cefalorraquidiano , Meningite/microbiologia , Meningite Criptocócica/líquido cefalorraquidiano , Meningite Criptocócica/diagnóstico , Metagenômica , Pessoa de Meia-Idade , Neuroaspergilose/líquido cefalorraquidiano , Neuroaspergilose/diagnóstico , Neurocisticercose/líquido cefalorraquidiano , Neurocisticercose/diagnóstico , Análise de Sequência de RNA/métodos , Taenia solium/genética , Adulto Jovem
8.
JCI Insight ; 1(14): e86704, 2016 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-27699234

RESUMO

Telomeres are short in type II alveolar epithelial cells (AECs) of patients with idiopathic pulmonary fibrosis (IPF). Whether dysfunctional telomeres contribute directly to development of lung fibrosis remains unknown. The objective of this study was to investigate whether telomere dysfunction in type II AECs, mediated by deletion of the telomere shelterin protein TRF1, leads to pulmonary fibrosis in mice (SPC-Cre TRF1fl/fl mice). Deletion of TRF1 in type II AECs for 2 weeks increased γH2AX DNA damage foci, but not histopathologic changes in the lung. Deletion of TRF1 in type II AECs for up to 9 months resulted in short telomeres and lung remodeling characterized by increased numbers of type II AECs, α-smooth muscle actin+ mesenchymal cells, collagen deposition, and accumulation of senescence-associated ß-galactosidase+ lung epithelial cells. Deletion of TRF1 in collagen-expressing cells caused pulmonary edema, but not fibrosis. These results demonstrate that prolonged telomere dysfunction in type II AECs, but not collagen-expressing cells, leads to age-dependent lung remodeling and fibrosis. We conclude that telomere dysfunction in type II AECs is sufficient to cause lung fibrosis, and may be a dominant molecular defect causing IPF. SPC-Cre TRF1fl/fl mice will be useful for assessing cellular and molecular mechanisms of lung fibrosis mediated by telomere dysfunction.


Assuntos
Células Epiteliais Alveolares/citologia , Pulmão/patologia , Fibrose Pulmonar/patologia , Telômero/patologia , Animais , Células Cultivadas , Células Epiteliais , Fibrose Pulmonar Idiopática , Camundongos , Encurtamento do Telômero
9.
PLoS One ; 11(6): e0158367, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27362652

RESUMO

Pathologic features of idiopathic pulmonary fibrosis (IPF) include genetic predisposition, activation of the unfolded protein response, telomere attrition, and cellular senescence. The mechanisms leading to alveolar epithelial cell (AEC) senescence are poorly understood. MicroRNAs (miRNAs) have been reported as regulators of cellular senescence. Senescence markers including p16, p21, p53, and senescence-associated ß-galactosidase (SA-ßgal) activity were measured in type II AECs from IPF lungs and unused donor lungs. miRNAs were quantified in type II AECs using gene expression arrays and quantitative RT-PCR. Molecular markers of senescence (p16, p21, and p53) were elevated in IPF type II AECs. SA-ßgal activity was detected in a greater percentage in type II AECs isolated from IPF patients (23.1%) compared to patients with other interstitial lung diseases (1.2%) or normal controls (0.8%). The relative levels of senescence-associated miRNAs miR-34a, miR-34b, and miR-34c, but not miR-20a, miR-29c, or miR-let-7f were significantly higher in type II AECs from IPF patients. Overexpression of miR-34a, miR-34b, or miR-34c in lung epithelial cells was associated with higher SA-ßgal activity (27.8%, 35.1%, and 38.2%, respectively) relative to control treated cells (8.8%). Targets of miR-34 miRNAs, including E2F1, c-Myc, and cyclin E2, were lower in IPF type II AECs. These results show that markers of senescence are uniquely elevated in IPF type II AECs and suggest that the miR-34 family of miRNAs regulate senescence in IPF type II AECs.


Assuntos
Células Epiteliais Alveolares/fisiologia , Senescência Celular/genética , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/patologia , MicroRNAs/fisiologia , Células A549 , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Biomarcadores/metabolismo , Estudos de Casos e Controles , Progressão da Doença , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Pulmão/metabolismo , Pulmão/patologia , Análise em Microsséries
10.
Oncotarget ; 7(29): 45916-45925, 2016 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-27322141

RESUMO

Mutations in the receptor tyrosine kinase c-KIT (KIT) are frequent oncogenic alterations in melanoma and are predominantly detected in tumors of acral, mucosal, and chronically sun-damaged skin. Research indicates that melanocytes with aberrant KIT signaling can be found in the distant periphery of the primary tumor; However, it is hitherto unknown whether KIT might confer a migratory advantage, thereby enabling genetically abnormal cells to populate a distal area. In this study, we investigated the role of mutant KIT in melanocyte- and melanoma cell migration using KIT mutant lines as well as genetically manipulated murine and primary human melanocytes. Our results revealed that melanocytes, stably transduced with mutant KIT closed a gap inflicted on cell monolayers faster than wild-type controls. Similarly, KIT mutant human melanoma lines were able to populate a larger area in a 3D in vitro skin model compared to KIT wild type and BRAF mutant lines. Genomic profiling revealed that genes associated with increased cell-dispersal of KIT mutant variants were linked to a statistically significant up-regulation of 60 migratory genes (z-score 1.334; p=0.0001). In addition, in vivo experiments harnessing a mouse xenograft model of early melanoma development demonstrated rapid lateral migration of KIT mutant cells compared to respective controls. The specific kinase inhibitors imatinib and nilotinib, could abrogate this migratory advantage in vitro and in vivo. Our work suggests that KIT inhibition might help to target migratory active, KIT mutant melanoma cells, thus representing a potential strategy to reduce spread and local recurrence.


Assuntos
Movimento Celular/genética , Melanócitos/patologia , Melanoma/patologia , Proteínas Proto-Oncogênicas c-kit/genética , Neoplasias Cutâneas/patologia , Animais , Movimento Celular/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanoma/genética , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Pirimidinas/farmacologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Invest Dermatol ; 136(10): 2041-2048, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27251789

RESUMO

In melanoma, mutant and thereby constantly active neuroblastoma rat sarcoma (NRAS) affects 15-20% of tumors, contributing to tumor initiation, growth, invasion, and metastasis. Recent therapeutic approaches aim to mimic RAS extinction by interfering with critical signaling pathways downstream of the mutant protein. This study investigates the phosphoproteome of primary human melanocytes bearing mutations in the two hot spots of NRAS, NRAS(G12) and NRAS(Q61). Stable isotope labeling by amino acids in cell culture followed by mass spectrometry identified 14,155 spectra of 3,371 unique phosphopeptides mapping to 1,159 proteins (false discovery rate < 2%). Data revealed pronounced PI3K/AKT signaling in NRAS(G12V) mutant cells and pronounced mitogen-activated protein kinase (MAPK) signaling in NRAS(Q61L) variants. Computer-based prediction models for kinases involved, revealed that CK2α is significantly overrepresented in primary human melanocytes bearing NRAS(Q61L) mutations. Similar differences were found in human NRAS(Q61) mutant melanoma cell lines that were also more sensitive to pharmacologic CK2α inhibition compared with NRAS(G12) mutant cells. Furthermore, CK2α levels were pronounced in patient samples of NRAS(Q61) mutant melanoma at the mRNA and protein level. The preclinical findings of this study reveal that codon 12 and 61 mutant NRAS cells have distinct signaling characteristics that could allow for the development of more effective, mutation-specific treatment modalities.


Assuntos
GTP Fosfo-Hidrolases/genética , Melanócitos/metabolismo , Melanoma/patologia , Proteínas de Membrana/genética , Proteômica/métodos , Neoplasias Cutâneas/patologia , Caseína Quinase II/metabolismo , Humanos , Espectrometria de Massas/métodos , Melanoma/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Fosfatidilinositol 3-Quinase/metabolismo , Fosfopeptídeos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais , Neoplasias Cutâneas/genética
13.
BMJ Open ; 5(6): e007535, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26063567

RESUMO

OBJECTIVES: Neuroimaging in chronic breathlessness is challenging. The study objective was to test the feasibility of magnetoencephalography (MEG) for functional neuroimaging of people with chronic breathlessness. DESIGN: Feasibility pilot study. SETTING: Respiratory clinic out-patients. PARTICIPANTS: 8 patients (mean age=62; (range 47-83); 4 men) with chronic non-malignant lung disease; modified MRC breathlessness score ≥ (median mMRC=4), intensity of exercise-induced breathlessness >3/10; no contraindication to MRI scanning. METHODS AND MEASURES: 4 MEG scans were conducted for each participant: (1) at rest (5 mins), (2) postseated leg exercise-induced breathlessness during recovery (10 mins). Recovery scans (2) were conducted with/without facial airflow in random order; both scans were repeated 1 h later. Participants rated breathlessness intensity (0-10 Numerical Rating Scale (NRS)) at baseline, maximal exertion and every minute during recovery, and rated acceptability of study procedures at the end of the study (0-10 NRS). A structural MRI scan was conducted for MEG coregistration and source-space analyses. Rest data were compared with data from healthy volunteers (N=6; 5 men; mean age=30.7 years ± 3.9 years). RESULTS: Exercises and MEG scanning were acceptable to all participants; 7/8 completed the MRI scans. Maximum breathlessness intensity was induced by 5 min' exercise. The same level was induced for repeat scans (median=8; IQR=7-8). All recovered to baseline by 10 min. Time-frequency profiles of data from the first and last 3 min were analysed in MEG source space based on breathlessness location estimates. Source localisation was performed, but anatomical source inference was limited to the level of the lobe. Differences in areas of activity were seen: during recovery scans; with and without airflow; and between participants/normal volunteers at rest. CONCLUSIONS: MEG is a feasible method to investigate exercise-induced breathlessness in people breathless with chronic lung disease, and able to identify neural activity related to changes in breathlessness.


Assuntos
Encéfalo/fisiopatologia , Dispneia , Exercício Físico/fisiologia , Pneumopatias/fisiopatologia , Magnetoencefalografia , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Ventilação Pulmonar
14.
Biomed Microdevices ; 17(1): 15, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25653058

RESUMO

BACKGROUND: Uveal melanoma (UM) is the most common primary intraocular malignancy in adults. Early treatment may improve any chances of preventing metastatic disease, but diagnosis of small UM is challenging. Up to 95 % of all UMs carry somatic mutations in the G-coupled proteins GNAQ and GNA11 promoting anchorage-independent growth and proliferation. About 50 % of UMs are fatal. Once metastatic, patients have limited options for successful therapy. METHODS: We have developed functionalized gold nanoparticles (AuNPs) to visualize transcripts of mutant GNAQ mRNA in living cells. In addition to their suitability as a specific tool for GNAQ mutation detection, we have developed a novel linker that enables conjugation of siRNAs to AuNPs allowing for greater and more rapid intracellular release of siRNAs compared to previously described approaches. RESULTS: Binding of modified AuNPs to matching target mRNA leads to conformational changes, resulting in a detectable fluorescent signal that can be used for mutation detection in living cells. Knockdown of GNAQ with siRNA-AuNPs effectively reduced downstream signals and decreased cell viability in GNAQ mutant uveal melanoma cells. CONCLUSION: AuNPs may in future be developed to serve as sensors for mutations of vital importance. The new release system for siRNA-AuNP improves previous systems, which conceivably will be useful for future therapeutic gene regulatory approaches.


Assuntos
Técnicas Biossensoriais/métodos , Subunidades alfa de Proteínas de Ligação ao GTP , Técnicas de Silenciamento de Genes/métodos , Ouro/química , Melanoma , Nanopartículas Metálicas/química , Mutação , Proteínas de Neoplasias , RNA Mensageiro , RNA Neoplásico , Neoplasias Uveais , Adulto , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP , Humanos , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Neoplasias Uveais/genética , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia
15.
Phys Med Rehabil Clin N Am ; 25(4): 897-913, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25442165

RESUMO

To help clinicians understand the risks associated with performance-enhancing drugs, this overview covers prohibited lists of substances and methods, therapeutic use exemptions, the legitimate indications and adverse effects, including for megadose and polypharmacy doping of stimulants, anabolic steroids, erythropoiesis-stimulating agents, and growth hormone and ways in which physicians or patients risk committing anti-doping rule violations inadvertently.


Assuntos
Suplementos Nutricionais/estatística & dados numéricos , Dopagem Esportivo , Substâncias para Melhoria do Desempenho/farmacologia , Medição de Risco , Humanos
16.
Nat Commun ; 4: 2946, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24336292

RESUMO

Nuclear magnetic resonance spectroscopy and imaging (MRI) play an indispensable role in science and healthcare but use only a tiny fraction of their potential. No more than ≈10 p.p.m. of all ¹H nuclei are effectively detected in a 3-Tesla clinical MRI system. Thus, a vast array of new applications lays dormant, awaiting improved sensitivity. Here we demonstrate the continuous polarization of small molecules in solution to a level that cannot be achieved in a viable magnet. The magnetization does not decay and is effectively reinitialized within seconds after being measured. This effect depends on the long-lived, entangled spin-order of parahydrogen and an exchange reaction in a low magnetic field of 10⁻³ Tesla. We demonstrate the potential of this method by fast MRI and envision the catalysis of new applications such as cancer screening or indeed low-field MRI for routine use and remote application.


Assuntos
Análise Química do Sangue/métodos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Análise Química do Sangue/instrumentação , Catálise , Desenho de Equipamento , Etanol/química , Humanos , Hidrogênio/química , Campos Magnéticos , Magnetismo , Metanol/química , Neoplasias/diagnóstico , Neoplasias/patologia , Piridinas/química , Água/química
17.
Proc Natl Acad Sci U S A ; 110(10): 4015-20, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23431193

RESUMO

Activating mutations in the neuroblastoma rat sarcoma viral oncogene homolog (NRAS) gene are common genetic events in malignant melanoma being found in 15-25% of cases. NRAS is thought to activate both mitogen activated protein kinase (MAPK) and PI3K signaling in melanoma cells. We studied the influence of different components on the MAP/extracellular signal-regulated (ERK) kinase (MEK) and PI3K/mammalian target of rapamycin (mTOR)-signaling cascade in NRAS mutant melanoma cells. In general, these cells were more sensitive to MEK inhibition compared with inhibition in the PI3K/mTOR cascade. Combined targeting of MEK and PI3K was superior to MEK and mTOR1,2 inhibition in all NRAS mutant melanoma cell lines tested, suggesting that PI3K signaling is more important for cell survival in NRAS mutant melanoma when MEK is inhibited. However, targeting of PI3K/mTOR1,2 in combination with MEK inhibitors is necessary to effectively abolish growth of NRAS mutant melanoma cells in vitro and regress xenografted NRAS mutant melanoma. Furthermore, we showed that MEK and PI3K/mTOR1,2 inhibition is synergistic. Expression analysis confirms that combined MEK and PI3K/mTOR1,2 inhibition predominantly influences genes in the rat sarcoma (RAS) pathway and growth factor receptor pathways, which signal through MEK/ERK and PI3K/mTOR, respectively. Our results suggest that combined targeting of the MEK/ERK and PI3K/mTOR pathways has antitumor activity and might serve as a therapeutic option in the treatment of NRAS mutant melanoma, for which there are currently no effective therapies.


Assuntos
GTP Fosfo-Hidrolases/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Proteínas de Membrana/genética , Inibidores de Fosfoinositídeo-3 Quinase , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Humanos , Melanoma/genética , Melanoma/patologia , Camundongos , Camundongos Nus , Mutação , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Front Hum Neurosci ; 6: 303, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23248594

RESUMO

Magnetoencephalography (MEG) enables non-invasive recording of neuronal activity, with reconstruction methods providing estimates of underlying brain source locations and oscillatory dynamics from externally recorded neuromagnetic fields. The aim of our study was to use MEG to determine the effect of manual acupuncture on neuronal oscillatory dynamics. A major problem in MEG investigations of manual acupuncture is the absence of onset times for each needle manipulation. Given that beamforming (spatial filtering) analysis is not dependent upon stimulus-driven responses being phase-locked to stimulus onset, we postulated that beamforming could reveal source locations and induced changes in neuronal activity during manual acupuncture. In a beamformer analysis, a two-minute period of manual acupuncture needle manipulation delivered to the ipsilateral right LI-4 (Hegu) acupoint was contrasted with a two-minute baseline period. We considered oscillatory power changes in the theta (4-8 Hz), alpha (8-13 Hz), beta (13-30 Hz), and gamma (30-100 Hz) frequency bands. We found significant decreases in beta band power in the contralateral primary somatosensory cortex and superior frontal gyrus (SFG). In the ipsilateral cerebral hemisphere, we found significant power decreases in beta and gamma frequency bands in only the SFG. No significant power modulations were found in theta and alpha bands. Our results indicate that beamforming is a useful analytical tool to reconstruct underlying neuronal activity associated with manual acupuncture. Our main finding was of beta power decreases in primary somatosensory cortex and SFG, which opens up a line of future investigation regarding whether this contributes toward an underlying mechanism of acupuncture.

19.
Neoplasia ; 13(2): 81-97, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21403835

RESUMO

A major challenge in cancer biology is to monitor and understand cancer metabolism in vivo with the goal of improved diagnosis and perhaps therapy. Because of the complexity of biochemical pathways, tracer methods are required for detecting specific enzyme-catalyzed reactions. Stable isotopes such as (13)C or (15)N with detection by nuclear magnetic resonance provide the necessary information about tissue biochemistry, but the crucial metabolites are present in low concentration and therefore are beyond the detection threshold of traditional magnetic resonance methods. A solution is to improve sensitivity by a factor of 10,000 or more by temporarily redistributing the populations of nuclear spins in a magnetic field, a process termed hyperpolarization. Although this effect is short-lived, hyperpolarized molecules can be generated in an aqueous solution and infused in vivo where metabolism generates products that can be imaged. This discovery lifts the primary constraint on magnetic resonance imaging for monitoring metabolism-poor sensitivity-while preserving the advantage of biochemical information. The purpose of this report was to briefly summarize the known abnormalities in cancer metabolism, the value and limitations of current imaging methods for metabolism, and the principles of hyperpolarization. Recent preclinical applications are described. Hyperpolarization technology is still in its infancy, and current polarizer equipment and methods are suboptimal. Nevertheless, there are no fundamental barriers to rapid translation of this exciting technology to clinical research and perhaps clinical care.


Assuntos
Biomarcadores Tumorais/metabolismo , Imageamento por Ressonância Magnética/métodos , Neoplasias/metabolismo , Biomarcadores Tumorais/química , Biomarcadores Tumorais/genética , Isótopos de Carbono/química , Fumaratos/química , Fumaratos/metabolismo , Humanos , Redes e Vias Metabólicas , Neoplasias/química , Neoplasias/patologia , Tomografia por Emissão de Pósitrons , Ácido Pirúvico/química , Ácido Pirúvico/metabolismo
20.
N Engl J Med ; 363(23): 2191-9, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-21083380

RESUMO

BACKGROUND: Uveal melanoma is the most common intraocular cancer. There are no effective therapies for metastatic disease. Mutations in GNAQ, the gene encoding an alpha subunit of heterotrimeric G proteins, are found in 40% of uveal melanomas. METHODS: We sequenced exon 5 of GNAQ and GNA11, a paralogue of GNAQ, in 713 melanocytic neoplasms of different types (186 uveal melanomas, 139 blue nevi, 106 other nevi, and 282 other melanomas). We sequenced exon 4 of GNAQ and GNA11 in 453 of these samples and in all coding exons of GNAQ and GNA11 in 97 uveal melanomas and 45 blue nevi. RESULTS: We found somatic mutations in exon 5 (affecting Q209) and in exon 4 (affecting R183) in both GNA11 and GNAQ, in a mutually exclusive pattern. Mutations affecting Q209 in GNA11 were present in 7% of blue nevi, 32% of primary uveal melanomas, and 57% of uveal melanoma metastases. In contrast, we observed Q209 mutations in GNAQ in 55% of blue nevi, 45% of uveal melanomas, and 22% of uveal melanoma metastases. Mutations affecting R183 in either GNAQ or GNA11 were less prevalent (2% of blue nevi and 6% of uveal melanomas) than the Q209 mutations. Mutations in GNA11 induced spontaneously metastasizing tumors in a mouse model and activated the mitogen-activated protein kinase pathway. CONCLUSIONS: Of the uveal melanomas we analyzed, 83% had somatic mutations in GNAQ or GNA11. Constitutive activation of the pathway involving these two genes appears to be a major contributor to the development of uveal melanoma. (Funded by the National Institutes of Health and others.).


Assuntos
Subunidades alfa de Proteínas de Ligação ao GTP/genética , Melanoma/genética , Mutação , Nevo Azul/genética , Neoplasias Uveais/genética , Animais , Células Cultivadas , Análise Mutacional de DNA , Éxons/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP , Humanos , Melanócitos , Melanoma/mortalidade , Melanoma/secundário , Camundongos , Transplante de Neoplasias , Nevo/genética , Nevo/mortalidade , Nevo Azul/mortalidade , Prognóstico , Análise de Sobrevida , Neoplasias Uveais/mortalidade
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