RESUMO
Substantial variation in relaxation rate exists among cardiomyocytes within small volumes of myocardium; however, it is unknown how this variability affects the overall relaxation mechanics of heart muscle. In this study, we sought to modulate levels of cellular heterogeneity in a computational model, then validate those predictions using an engineered heart tissue platform. We formulated an in silico tissue model composed of half-sarcomeres with varied relaxation rates, incorporating single-cell cardiomyocyte experimental data. These model tissues randomly sampled relaxation parameters from two offset distributions of fast- and slow-relaxing populations of half-sarcomeres. Isometric muscle twitch simulations predicted a complex relationship between relaxation time and the proportion of fast-versus slow-relaxing cells in heterogeneous tissues. Specifically, a 50/50 mixture of fast and slow cells did not lead to relaxation time that was the mean of the relaxation times associated with the two pure cases. Rather, the mean relaxation time was achieved at a ratio of 70:30 slow:fast relaxing cells, suggesting a disproportionate impact of fast-relaxing cells on overall tissue relaxation. To examine whether this behavior persists in vitro, we constructed engineered heart tissues from two lines of fast- and slow-relaxing human iPSC-derived cardiomyocytes. Cell tracking via fluorescent nanocrystals confirmed the presence of both cell populations in the 50/50 mixed tissues at the time of mechanical characterization. Isometric muscle twitch relaxation times of these mixed-population engineered heart tissues showed agreement with the predictions from the model, namely that the measured relaxation rate of 50/50 mixed tissues more closely resembled that of tissues made with 100% fast-relaxing cells. Our observations suggest that cardiomyocyte diversity can play an important role in determining tissue-level relaxation.
Assuntos
Modelos Cardiovasculares , Relaxamento Muscular , Miócitos Cardíacos/metabolismo , Cinética , Miócitos Cardíacos/citologia , Engenharia TecidualRESUMO
PURPOSE OF REVIEW: Androgen deprivation therapy (ADT) is widely used in prostate cancer. Interest in assessing how ADT impacts cognition is growing. RECENT FINDINGS: Studies in animals and humans suggest that androgens may affect cognitive function. However, extant studies utilizing common neurocognitive tests have not consistently demonstrated ADT-induced cognitive impairment. Retrospective analyses investigating the association between ADT and risk of dementia in large electronic patient databases have also produced conflicting results. There is only limited data on ADT-induced changes in the brain as detected by functional imaging. It remains unclear whether cognitive deficits can occur in a patient undergoing ADT. Commonly used neurocognitive tests may not be optimal for detection of more subtle but clinically relevant cognitive impairment. While large electronic patient databases are attractive sources of information, their heterogeneity, complexity, and potential reporting biases can be a challenge. Better tools are needed to assess the cognitive impact of ADT prospectively.
Assuntos
Antagonistas de Androgênios/efeitos adversos , Antagonistas de Androgênios/uso terapêutico , Transtornos Cognitivos/induzido quimicamente , Cognição/efeitos dos fármacos , Doenças Neurodegenerativas/induzido quimicamente , Neoplasias da Próstata/tratamento farmacológico , Antagonistas de Androgênios/farmacologia , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Transtornos Cognitivos/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Doenças Neurodegenerativas/diagnóstico , Testes NeuropsicológicosRESUMO
BACKGROUND: Fibrosis and stricture are major comorbidities in patients with eosinophilic esophagitis (EoE). Lysyl oxidase (LOX), a collagen cross-linking enzyme, has not been investigated in the context of EoE. OBJECTIVE: We investigated regulation of epithelial LOX expression as a novel biomarker and functional effector of fibrostenotic disease conditions associated with EoE. METHODS: LOX expression was analyzed by using RNA-sequencing, PCR assays, and immunostaining in patients with EoE; cytokine-stimulated esophageal 3-dimensional organoids; and fibroblast-epithelial cell coculture, the latter coupled with fluorescence-activated cell sorting. RESULTS: Gene ontology and pathway analyses linked TNF-α and LOX expression in patients with EoE, which was validated in independent sets of patients with fibrostenotic conditions. TNF-α-mediated epithelial LOX upregulation was recapitulated in 3-dimensional organoids and coculture experiments. We find that fibroblast-derived TNF-α stimulates epithelial LOX expression through activation of nuclear factor κB and TGF-ß-mediated signaling. In patients receiver operating characteristic analyses suggested that LOX upregulation indicates disease complications and fibrostenotic conditions in patients with EoE. CONCLUSIONS: There is a novel positive feedback mechanism in epithelial LOX induction through fibroblast-derived TNF-α secretion. Esophageal epithelial LOX might have a role in the development of fibrosis with substantial translational implications.
Assuntos
Biomarcadores/metabolismo , Esofagite Eosinofílica/genética , Células Epiteliais/fisiologia , Esôfago/patologia , Fibroblastos/fisiologia , Proteína-Lisina 6-Oxidase/genética , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Idoso , Células Cultivadas , Criança , Pré-Escolar , Técnicas de Cocultura , Constrição Patológica , Esofagite Eosinofílica/diagnóstico , Feminino , Fibrose , Ontologia Genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Proteína-Lisina 6-Oxidase/metabolismo , Regulação para Cima , Adulto JovemRESUMO
OBJECTIVE: To evaluate the effect of colchicine and high-intensity rosuvastatin in addition to standard of care on the progression of COVID-19 disease in hospitalised patients. DESIGN: A pragmatic, open-label, multicentre, randomised controlled trial conducted from October 2020 to September 2021. Follow-up was conducted at 30 and 60 days. The electronic medical record was used at all stages of the trial including screening, enrolment, randomisation, event ascertainment and follow-up. SETTING: Four centres in the Yale New Haven Health System. PARTICIPANTS: Non-critically ill hospitalised patients with COVID-19. INTERVENTIONS: Patients were randomised 1:1 to either colchicine plus high-intensity rosuvastatin in addition to standard of care versus standard of care alone. Assigned treatment was continued for the duration of index hospitalisation or 30 days, whichever was shorter. PRIMARY AND SECONDARY OUTCOME MEASURES: The prespecified primary endpoint was progression to severe COVID-19 disease (new high-flow or non-invasive ventilation, mechanical ventilation, need for vasopressors, renal replacement therapy or extracorporeal membrane oxygenation, or death) or arterial/venous thromboembolic events (ischaemic stroke, myocardial infarction, deep venous thrombosis or pulmonary embolism) evaluated at 30 days. RESULTS: Among the 250 patients randomised in this trial (125 to each arm), the median age was 61 years, 44% were women, 15% were Black and 26% were Hispanic/Latino. As part of the standard of care, patients received remdesivir (87%), dexamethasone (92%), tocilizumab (18%), baricitinib (2%), prophylactic/therapeutic anticoagulation (98%) and aspirin (91%). The trial was terminated early by the data and safety monitoring board for futility. No patients were lost to follow-up due to electronic medical record follow-up. There was no significant difference in the primary endpoint at 30 days between the active arm and standard of care arm (15.2% vs 8.8%, respectively, p=0.17). CONCLUSIONS: In this small, open-label, randomised trial of non-critically ill hospitalised patients with COVID-19, the combination of colchicine and rosuvastatin in addition to standard of care did not appear to reduce the risk of progression of COVID-19 disease or thromboembolic events, although the trial was underpowered due to a lower-than-expected event rate. The trial leveraged the power of electronic medical records for efficiency and improved follow-up and demonstrates the utility of incorporating electronic medical records into future trials. TRIAL REGISTRATION: NCT04472611.
Assuntos
Isquemia Encefálica , COVID-19 , Acidente Vascular Cerebral , Feminino , Humanos , Pessoa de Meia-Idade , Masculino , Rosuvastatina Cálcica , SARS-CoV-2 , Colchicina , Resultado do TratamentoRESUMO
BACKGROUND: Despite improvement in the standard of care (SOC) for hospitalized COVID-19 patients, rates of morbidity and mortality remain high. There continues to be a need for easily available and cost-effective treatments. Colchicine and rosuvastatin are both safe and well-studied medications with anti-inflammatory and other pleiotropic effects that may provide additional benefits to hospitalized COVID-19 patients. METHODS AND RESULTS: The Colchicine/Statin for the Prevention of COVID-19 Complications (COLSTAT) trial is a pragmatic, open-label, multicenter, randomized trial comparing the combination of colchicine and rosuvastatin in addition to SOC to SOC alone in hospitalized COVID-19 patients. Four centers in the Yale New Haven Health network will enroll a total of 466 patients with 1:1 randomization. The trial will utilize the electronic health record (Epic® Systems, Verona, Wisconsin, USA) at all stages including screening, randomization, intervention, event ascertainment, and follow-up. The primary endpoint is the 30-day composite of progression to severe COVID-19 disease as defined by the World Health Organization ordinal scale of clinical improvement and arterial/venous thromboembolic events. The secondary powered endpoint is the 30-day composite of death, respiratory failure requiring intubation, and myocardial injury. CONCLUSIONS: The COLSTAT trial will provide evidence on the efficacy of repurposing colchicine and rosuvastatin for the treatment of hospitalized COVID-19 patients. Moreover, it is designed to be a pragmatic trial that will demonstrate the power of using electronic health records to improve efficiency and enrollment in clinical trials in an adapting landscape. CLINICAL TRIAL REGISTRATION: NCT04472611 (https://clinicaltrials.gov/ct2/show/NCT04472611).
Assuntos
COVID-19 , Inibidores de Hidroximetilglutaril-CoA Redutases , Colchicina/uso terapêutico , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , SARS-CoV-2 , Resultado do TratamentoRESUMO
Reducing severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infections among healthcare workers is critical. We ran Monte Carlo simulations modeling the spread of SARS-CoV-2 in non-COVID-19 wards, and we found that longer nursing shifts and scheduling designs in which teams of nurses and doctors co-rotate no more frequently than every 3 days can lead to fewer infections.
Assuntos
COVID-19 , Mão de Obra em Saúde/organização & administração , Controle de Infecções/métodos , Corpo Clínico Hospitalar , Admissão e Escalonamento de Pessoal , Gestão da Segurança/normas , COVID-19/epidemiologia , COVID-19/prevenção & controle , Connecticut/epidemiologia , Humanos , Corpo Clínico Hospitalar/organização & administração , Corpo Clínico Hospitalar/estatística & dados numéricos , Exposição Ocupacional/prevenção & controle , Inovação Organizacional , Admissão e Escalonamento de Pessoal/organização & administração , Admissão e Escalonamento de Pessoal/normas , Admissão e Escalonamento de Pessoal/tendências , SARS-CoV-2 , Gestão da Segurança/organização & administraçãoRESUMO
Hypertrophic cardiomyopathy (HCM) is often caused by single sarcomeric gene mutations that affect muscle contraction. Pharmacological correction of mutation effects prevents but does not reverse disease in mouse models. Suspecting that diseased extracellular matrix is to blame, we obtained myocardium from a miniature swine model of HCM, decellularized thin slices of the tissue, and re-seeded them with healthy human induced pluripotent stem cell-derived cardiomyocytes. Compared with cardiomyocytes grown on healthy extracellular matrix, those grown on the diseased matrix exhibited prolonged contractions and poor relaxation. This outcome suggests that extracellular matrix abnormalities must be addressed in therapies targeting established HCM.