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1.
Crit Rev Clin Lab Sci ; 61(4): 254-274, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38809116

RESUMO

No standard tool to measure pathologist workload currently exists. An accurate measure of workload is needed for determining the number of pathologists to be hired, distributing the workload fairly among pathologists, and assessing the overall cost of pathology consults. Initially, simple tools such as counting cases or slides were used to give an estimate of the workload. More recently, multiple workload models, including relative value units (RVUs), the Royal College of Pathologists (RCP) point system, Level 4 Equivalent (L4E), Work2Quality (W2Q), and the University of Washington, Seattle (UW) slide count method, have been developed. There is no "ideal" model that is universally accepted. The main differences among the models come from the weights assigned to different specimen types, differential calculations for organs, and the capture of additional tasks needed for safe and timely patient care. Academic centers tend to see more complex cases that require extensive sampling and additional testing, while community-based and private laboratories deal more with biopsies. Additionally, some systems do not account for teaching, participation in multidisciplinary rounds, quality assurance activities, and medical oversight. A successful workload model needs to be continually updated to reflect the current state of practice.Awareness about physician burnout has gained attention in recent years and has been added to the World Health Organization's International Classification of Diseases (World Health Organization, WHO) as an occupational phenomenon. However, the extent to which this affects pathologists is not well understood. According to the WHO, burnout syndrome is diagnosed by the presence of three components: emotional exhaustion, depersonalization from one's work (cynicism related to one's job), and a low sense of personal achievement or accomplishment. Three drivers of burnout are the demand for productivity, lack of recognition, and electronic health records. Prominent consequences of physician burnout are economic and personal costs to the public and to the providers.Wellness is physical and mental well-being that allows individuals to manage stress effectively and to thrive in both their professional and personal lives. To achieve wellness, it is necessary to understand the root causes of burnout, including over-work and working under stressful conditions. Wellness is more than the absence of stress or burnout, and the responsibility of wellness should be shared by pathologists themselves, their healthcare organization, and governing bodies. Each pathologist needs to take their own path to achieve wellness.


Assuntos
Esgotamento Profissional , Patologistas , Carga de Trabalho , Humanos
2.
Histopathology ; 85(2): 207-214, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38516992

RESUMO

Digital pathology (DP) has emerged as a cutting-edge technology that promises to revolutionise diagnostics in clinical laboratories. This perspective article explores the implementation planning and considerations of DP in a single multicentre institution in Canada, the University Health Network, discussing benefits, challenges, potential implications and considerations for future adopters. We examine the transition from traditional microscopy to digital slide scanning and its impact on pathology practice, patient care and medical research. Furthermore, we address the regulatory, infrastructure and change management considerations for successful integration into clinical laboratories. By highlighting the advantages and addressing concerns, we aim to shed light on the transformative potential of DP and its role in shaping the future of diagnostics.


Assuntos
Laboratórios Clínicos , Patologia Clínica , Humanos , Patologia Clínica/métodos , Canadá , Microscopia/métodos
3.
PLoS Comput Biol ; 18(5): e1010061, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35500032

RESUMO

While hierarchical experimental designs are near-ubiquitous in neuroscience and biomedical research, researchers often do not take the structure of their datasets into account while performing statistical hypothesis tests. Resampling-based methods are a flexible strategy for performing these analyses but are difficult due to the lack of open-source software to automate test construction and execution. To address this, we present Hierarch, a Python package to perform hypothesis tests and compute confidence intervals on hierarchical experimental designs. Using a combination of permutation resampling and bootstrap aggregation, Hierarch can be used to perform hypothesis tests that maintain nominal Type I error rates and generate confidence intervals that maintain the nominal coverage probability without making distributional assumptions about the dataset of interest. Hierarch makes use of the Numba JIT compiler to reduce p-value computation times to under one second for typical datasets in biomedical research. Hierarch also enables researchers to construct user-defined resampling plans that take advantage of Hierarch's Numba-accelerated functions.


Assuntos
Projetos de Pesquisa , Software , Probabilidade
4.
Ann Intern Med ; 174(3): 326-334, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33226855

RESUMO

BACKGROUND: Anticipated success rates and timelines for COVID-19 vaccine development vary. Recent experience with developing and testing viral vaccine candidates can inform expectations regarding the development of safe and effective vaccines. OBJECTIVE: To estimate timelines and probabilities of success for recent vaccine candidates. DESIGN: ClinicalTrials.gov was searched to identify trials testing viral vaccines that had not advanced to phase 2 before 2005, and the progress of each vaccine from phase 1 through to U.S. Food and Drug Administration (FDA) licensure was tracked. Trial characteristics were double-coded. (Registration: Open Science Framework [https://osf.io/dmuzx/]). SETTING: Trials launched between January 2005 and March 2020. PARTICIPANTS: Preventive viral vaccine candidates for 23 emerging or reemerged viral infectious diseases. MEASUREMENTS: The primary end point was the probability of vaccines advancing from launch of phase 2 to FDA licensure within 10 years. RESULTS: In total, 606 clinical trials forming 220 distinct development trajectories (267 343 enrolled participants) were identified. The probability of vaccines progressing from phase 2 to licensure within 10 years was 10.0% (95% CI, 2.6% to 16.9%), with most approvals representing H1N1 or H5N1 vaccines. The average timeline from phase 2 to approval was 4.4 years (range, 6.4 weeks to 13.9 years). The probabilities of advancing from phase 1 to 2, phase 2 to 3, and phase 3 to licensure within the total available follow-up time were 38.2% (CI, 30.7% to 45.0%), 38.3% (CI, 23.1% to 50.5%), and 61.1% (CI, 3.7% to 84.3%), respectively. LIMITATIONS: The study did not account for preclinical development and relied primarily on ClinicalTrials.gov and FDA resources. Success probabilities do not capture the varied reasons why vaccines fail to advance to regulatory approval. CONCLUSION: Success probabilities and timelines varied widely across different vaccine types and diseases. If a SARS-CoV-2 vaccine is licensed within 18 months of the start of the pandemic, it will mark an unprecedented achievement for noninfluenza viral vaccine development. PRIMARY FUNDING SOURCE: McGill Interdisciplinary Initiative in Infection and Immunity (MI4) Emergency COVID-19 Research Funding program.


Assuntos
Doenças Transmissíveis Emergentes/prevenção & controle , Aprovação de Drogas , Desenvolvimento de Medicamentos , Viroses/prevenção & controle , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Estudos Retrospectivos , SARS-CoV-2 , Fatores de Tempo , Estados Unidos , United States Food and Drug Administration
5.
Cereb Cortex ; 30(4): 2372-2388, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-31761935

RESUMO

Huntington's disease (HD) is a neurodegenerative disorder characterized by involuntary movements, cognitive deficits, and psychiatric disturbances. Although evidence indicates that projections from motor cortical areas play a key role in the development of dysfunctional striatal activity and motor phenotype, little is known about the changes in cortical microcircuits and their role in the development of the HD phenotype. Here we used two-photon laser-scanning microscopy to evaluate network dynamics of motor cortical neurons in layers II/III in behaving transgenic R6/2 and knock-in Q175+/- mice. Symptomatic R6/2 mice displayed increased motion manifested by a significantly greater number of motion epochs, whereas symptomatic Q175 mice displayed decreased motion. In both models, calcium transients in symptomatic mice displayed reduced amplitude, suggesting decreased bursting activity. Changes in frequency were genotype- and time-dependent; for R6/2 mice, the frequency was reduced during both motion and nonmotion, whereas in symptomatic Q175 mice, the reduction only occurred during nonmotion. In presymptomatic Q175 mice, frequency was increased during both behavioral states. Interneuronal correlation coefficients were generally decreased in both models, suggesting disrupted interneuronal communication in HD cerebral cortex. These results indicate similar and contrasting effects of the HD mutation on cortical ensemble activity depending on mouse model and disease stage.


Assuntos
Cálcio , Modelos Animais de Doenças , Doença de Huntington/diagnóstico por imagem , Doença de Huntington/genética , Córtex Motor/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Animais , Cálcio/metabolismo , Feminino , Doença de Huntington/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Córtex Motor/metabolismo , Neurônios Motores/metabolismo , Rede Nervosa/metabolismo
6.
BMC Nephrol ; 22(1): 313, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34530746

RESUMO

BACKGROUND: SARS-CoV-2 can remain transiently viable on surfaces. We examined if use of shared chairs in outpatient hemodialysis associates with a risk for indirect patient-to-patient transmission of SARS-CoV-2. METHODS: We used data from adults treated at 2,600 hemodialysis facilities in United States between February 1st and June 8th, 2020. We performed a retrospective case-control study matching each SARS-CoV-2 positive patient (case) to a non-SARS-CoV-2 patient (control) treated in the same dialysis shift. Cases and controls were matched on age, sex, race, facility, shift date, and treatment count. For each case-control pair, we traced backward 14 days to assess possible prior exposure from a 'shedding' SARS-CoV-2 positive patient who sat in the same chair immediately before the case or control. Conditional logistic regression models tested whether chair exposure after a shedding SARS-CoV-2 positive patient conferred a higher risk of SARS-CoV-2 infection to the immediate subsequent patient. RESULTS: Among 170,234 hemodialysis patients, 4,782 (2.8 %) tested positive for SARS-CoV-2 (mean age 64 years, 44 % female). Most facilities (68.5 %) had 0 to 1 positive SARS-CoV-2 patient. We matched 2,379 SARS-CoV-2 positive cases to 2,379 non-SARS-CoV-2 controls; 1.30 % (95 %CI 0.90 %, 1.87 %) of cases and 1.39 % (95 %CI 0.97 %, 1.97 %) of controls were exposed to a chair previously sat in by a shedding SARS-CoV-2 patient. Transmission risk among cases was not significantly different from controls (OR = 0.94; 95 %CI 0.57 to 1.54; p = 0.80). Results remained consistent in adjusted and sensitivity analyses. CONCLUSIONS: The risk of indirect patient-to-patient transmission of SARS-CoV-2 infection from dialysis chairs appears to be low.


Assuntos
Instituições de Assistência Ambulatorial , COVID-19/transmissão , Fômites/virologia , Decoração de Interiores e Mobiliário , Pacientes Ambulatoriais , Diálise Renal , Eliminação de Partículas Virais , Idoso , COVID-19/epidemiologia , Estudos de Casos e Controles , Exposição Ambiental , Feminino , Humanos , Controle de Infecções/métodos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Estudos Retrospectivos , Risco , SARS-CoV-2 , Estados Unidos/epidemiologia
7.
Dermatol Online J ; 27(1)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33560783

RESUMO

The severe acute respiratory syndrome coronavirus two (SARS-CoV-2), which causes the 2019 coronavirus disease (COVID-19), has infected patients worldwide. Physicians have increasingly identified cutaneous findings as a significant clinical manifestation of COVID-19. In this review, we describe the clinical presentation, onset, duration, associated symptoms, treatment, and outcome of cutaneous manifestations thus far reported to be related to COVID-19. We have included data from 63 studies and subdivided reported cutaneous manifestations into the categories of viral exanthem, urticarial, vesicular, chilblains/chilblains-like, non-chilblains vasculopathy-related, pityriasis rosea-like, erythema multiforme-like, Kawasaki/Kawasaki-like disease, and others. Physicians should be aware of the known common cutaneous manifestations of COVID-19 and future research is required to better understand the pathophysiology and prognosis of each COVID-19-related skin manifestation.


Assuntos
COVID-19/fisiopatologia , Dermatopatias/fisiopatologia , Pérnio/fisiopatologia , Eritema Multiforme/fisiopatologia , Exantema/fisiopatologia , Humanos , Síndrome de Linfonodos Mucocutâneos/fisiopatologia , Pitiríase Rósea/fisiopatologia , SARS-CoV-2 , Dermatopatias Vasculares/fisiopatologia , Dermatopatias Vesiculobolhosas/fisiopatologia , Síndrome de Resposta Inflamatória Sistêmica/fisiopatologia , Urticária/fisiopatologia
8.
Am J Physiol Heart Circ Physiol ; 318(2): H378-H390, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31886717

RESUMO

Myostatin (MSTN) is a transforming growth factor (TGF)-ß superfamily member that acts as a negative regulator of muscle growth and may play a role in cardiac remodeling. We hypothesized that inhibition of activin type II receptors (ACTRII) to reduce MSTN signaling would reduce pathological cardiac remodeling in experimental heart failure (HF). C57BL/6J mice underwent left anterior descending coronary artery ligation under anesthesia to induce myocardial infarction (MI) or no ligation (sham). MI and sham animals were each randomly divided into groups (n ≥ 10 mice/group) receiving an ACTRII or ACTRII/TGFß receptor-signaling inhibiting strategy: 1) myo-Fc group (weekly 10 mg/kg Myo-Fc) or 2) Fol + TGFi group (daily 12 µg/kg follistatin plus 2 mg/kg TGFß receptor inhibitor), versus controls. ACTRII/TGFBR signaling inhibition preserved cardiac function by echocardiography and prevented an increase in brain natriuretic peptide (BNP). ACTRII/TGFBR inhibition resulted in increased phosphorylation (P) of Akt and decreased P-p38 mitogen-activated protein kinase (MAPK) in MI mice. In vitro, Akt contributed to P-SMAD2,3, P-p38, and BNP regulation in cardiomyocytes. ACTRII/TGFBR inhibition increased sarco/endoplasmic reticulum Ca2+-ATPase (SERCA2a) levels and decreased unfolded protein response (UPR) markers in MI mice. ACTRII/TGFBR inhibition was associated with a decrease in cardiac fibrosis and fibrosis markers, connective tissue growth factor (CTGF), type I collagen, fibronectin, α-smooth muscle actin, and matrix metalloproteinase (MMP)-12 in MI mice. MSTN exerted a direct regulation on the UPR marker eukaryotic translation initiation factor-2α (eIf2α) in cardiomyocytes. Our study suggests that ACTRII ligand inhibition has beneficial effects on cardiac signaling and fibrosis after ischemic HF.NEW & NOTEWORTHY Activin type II receptor ligand inhibition resulted in preserved cardiac function, a decrease in cardiac fibrosis, improved SERCA2a levels, and a prevention of the unfolded protein response in mice with myocardial infarction.


Assuntos
Receptores de Activinas Tipo II/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/fisiopatologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Ecocardiografia , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Miostatina/antagonistas & inibidores , Miostatina/metabolismo , Peptídeo Natriurético Encefálico/metabolismo , Fosforilação , Resistência Física , Receptor do Fator de Crescimento Transformador beta Tipo I/antagonistas & inibidores , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
Am J Physiol Heart Circ Physiol ; 315(5): H1463-H1476, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30141986

RESUMO

Clinical and experimental studies have suggested that the duration of left ventricular assist device (LVAD) support may affect remodeling of the failing heart. We aimed to 1) characterize the changes in Ca2+/calmodulin-dependent protein kinase type-IIδ (CaMKIIδ), growth signaling, structural proteins, fibrosis, apoptosis, and gene expression before and after LVAD support and 2) assess whether the duration of support correlated with improvement or worsening of reverse remodeling. Left ventricular apex tissue and serum pairs were collected in patients with dilated cardiomyopathy ( n = 25, 23 men and 2 women) at LVAD implantation and after LVAD support at cardiac transplantation/LVAD explantation. Normal cardiac tissue was obtained from healthy hearts ( n = 4) and normal serum from age-matched control hearts ( n = 4). The duration of LVAD support ranged from 48 to 1,170 days (median duration: 270 days). LVAD support was associated with CaMKIIδ activation, increased nuclear myocyte enhancer factor 2, sustained histone deacetylase-4 phosphorylation, increased circulating and cardiac myostatin (MSTN) and MSTN signaling mediated by SMAD2, ongoing structural protein dysregulation and sustained fibrosis and apoptosis (all P < 0.05). Increased CaMKIIδ phosphorylation, nuclear myocyte enhancer factor 2, and cardiac MSTN significantly correlated with the duration of support. Phosphorylation of SMAD2 and apoptosis decreased with a shorter duration of LVAD support but increased with a longer duration of LVAD support. Further study is needed to define the optimal duration of LVAD support in patients with dilated cardiomyopathy. NEW & NOTEWORTHY A long duration of left ventricular assist device support may be detrimental for myocardial recovery, based on myocardial tissue experiments in patients with prolonged support showing significantly worsened activation of Ca2+/calmodulin-dependent protein kinase-IIδ, increased nuclear myocyte enhancer factor 2, increased myostatin and its signaling by SMAD2, and apoptosis as well as sustained histone deacetylase-4 phosphorylation, structural protein dysregulation, and fibrosis.


Assuntos
Cardiomiopatia Dilatada/terapia , Insuficiência Cardíaca/terapia , Ventrículos do Coração/metabolismo , Coração Auxiliar , Miocárdio/metabolismo , Função Ventricular Esquerda , Apoptose , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Estudos de Casos e Controles , Feminino , Fibrose , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Histona Desacetilases/metabolismo , Humanos , Fatores de Transcrição MEF2/metabolismo , Masculino , Pessoa de Meia-Idade , Miostatina/metabolismo , Fosforilação , Desenho de Prótese , Recuperação de Função Fisiológica , Proteínas Repressoras/metabolismo , Transdução de Sinais , Proteína Smad2/metabolismo , Fatores de Tempo , Resultado do Tratamento , Remodelação Ventricular
10.
Br J Neurosurg ; 32(2): 201-205, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29017364

RESUMO

OBJECTIVE: We reviewed the safety of our practice of admitting patients who have undergone a craniotomy for resection of an intra-axial brain tumor to a floor bed instead of an ICU. We also tried to quantify the risk that patients electively admitted to the ICU would develop a problem that could not have been effectively managed on the ward. METHODS: A retrospective chart review was performed of both adult and pediatric patients who underwent craniotomy by the senior author for resection of an intra-axial brain tumor between January 2012 and December 2015. 413 patient charts were reviewed; 16 patients were omitted due to incomplete records. RESULTS: Four hundred twenty-one craniotomies (393 supratentorial, 28 infratentorial) were performed in 397 patients, 35 of whom were <18 years of age. Three hundred fifty-five patients (83%) were admitted to floor beds; 4 (1.1%) developed complications that required transfer to an ICU. None of the 4 died or had lasting disability. Sixty-six patients, 51 adults and 15 children, were admitted to the ICU after their operation. Twenty-five of these patients had an absolute indication for ICU admission: 9 required a ventilator, 14 had an EVD and 2 were medically unstable. Of the remaining 41, none developed a complication that would have required transfer to an ICU had they been on the ward. CONCLUSION: It is safe to admit almost all patients to a floor bed after craniotomy for intra-axial brain tumor resection. The risk of a catastrophic problem occurring after a 4 hour stay in the post anesthesia care unit is extremely low. Furthermore, even patients who are electively managed in an ICU are unlikely to develop problems that would lead to a worse outcome had they been in a floor bed.


Assuntos
Neoplasias Encefálicas/cirurgia , Craniotomia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Departamentos Hospitalares , Humanos , Lactente , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Segurança do Paciente , Transferência de Pacientes , Complicações Pós-Operatórias/terapia , Respiração Artificial/estatística & dados numéricos , Estudos Retrospectivos , Adulto Jovem
11.
J Stroke Cerebrovasc Dis ; 27(3): 793-800, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29158056

RESUMO

OBJECTIVES: Our study aimed to report both new and previously identified conditions associated with moyamoya syndrome in a Western population and to present our outcomes after surgical treatment with indirect bypass. METHODS: We performed a retrospective chart review of patients evaluated at our institution from June 2011 to June 2015 who were diagnosed with moyamoya. Data collected include patient demographics, presenting manifestations, vessels involved, comorbid conditions, abnormal laboratory values, treatments administered, and clinical outcomes. RESULTS: Thirty-one patients with moyamoya were enrolled (11 male and 20 female), with 84% Caucasian and 16% African-American. The most common comorbidity was hypertension in 61% of the patients. Coexisting autoimmune conditions were present in 26%, with another 13% having coexisting prothrombotic disorders. Diabetes mellitus was not found to correlate with the Suzuki grade of disease at presentation (P = .30). When noninvasive imaging was performed before the cerebral angiogram, the computed tomography angiography had a false-negative rate of 59%, and magnetic resonance angiography had a false-negative rate of 33%. Twenty-one patients underwent surgical intervention, 2 underwent intracranial stenting, and 19 underwent indirect bypass with encephaloduroarteriosynangiosis. At an average 28-month follow-up, all 15 patients who had an angiogram after intervention showed evidence of neovascularization. CONCLUSIONS: Autoimmune and prothrombotic disorders were found to be comorbid in patients with moyamoya at much higher rates than expected in the general population. Diabetes mellitus was not significantly correlated with Suzuki grade. Angiogram remains an important diagnostic modality when noninvasive imaging is negative for vasculopathy. We demonstrate excellent evidence of revascularization within 1 year with intracranial stenting and indirect bypass.


Assuntos
Doença de Moyamoya/epidemiologia , Adolescente , Adulto , Negro ou Afro-Americano , Idoso , Doenças Autoimunes/epidemiologia , Transtornos da Coagulação Sanguínea/epidemiologia , Angiografia Cerebral/métodos , Criança , Comorbidade , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/instrumentação , Feminino , Humanos , Kentucky/epidemiologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/fisiopatologia , Doença de Moyamoya/terapia , Neovascularização Fisiológica , Procedimentos Neurocirúrgicos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Stents , Fatores de Tempo , Resultado do Tratamento , População Branca , Adulto Jovem
12.
Am J Physiol Heart Circ Physiol ; 309(3): H459-70, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26055788

RESUMO

Abnormal intracellular calcium (Ca(2+)) handling can trigger endoplasmic reticulum (ER) stress, leading to activation of the unfolded protein response (UPR) in an attempt to prevent cell death. Mechanical unloading with a left ventricular assist device (LVAD) relieves pressure-volume overload and promotes reverse remodeling of the failing myocardium. We hypothesized that mechanical unloading would alter the UPR in patients with advanced heart failure (HF). UPR was analyzed in paired myocardial tissue from 10 patients with dilated cardiomyopathy obtained during LVAD implantation and explantation. Samples from healthy hearts served as controls. Markers of UPR [binding immunoglobulin protein (BiP), phosphorylated (P-) eukaryotic initiation factor (eIF2α), and X-box binding protein (XBP1)] were significantly increased in HF, whereas LVAD support significantly decreased BiP, P-eIF2α, and XBP1s levels. Apoptosis as reflected by C/EBP homologous protein and DNA damage were also significantly reduced after LVAD support. Improvement in left ventricular dimensions positively correlated with P-eIF2α/eIF2α and apoptosis level recovery. Furthermore, significant dysregulation of calcium-handling proteins [P-ryanodine receptor, Ca(2+) storing protein calsequestrin, Na(+)-Ca(2+) exchanger, sarcoendoplasmic reticulum Ca(2+)-ATPase (SERCA2a), ER chaperone protein calreticulin] was normalized after LVAD support. Reduced ER Ca(2+) content as a causative mechanism for UPR was confirmed using AC16 cells treated with a calcium ionophore (A23187) and SERCA2a inhibitor (thapsigargin). UPR activation and apoptosis are reduced after mechanical unloading, which may be mediated by the improvement of Ca(2+) handling in patients with advanced HF. These changes may impact the potential for myocardial recovery.


Assuntos
Cardiomiopatia Dilatada/metabolismo , Estresse do Retículo Endoplasmático , Coração Auxiliar , Resposta a Proteínas não Dobradas , Apoptose , Calreticulina/genética , Calreticulina/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Dilatada/cirurgia , Estudos de Casos e Controles , Linhagem Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Transcrição de Fator Regulador X , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína 1 de Ligação a X-Box , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
13.
Biochem Biophys Res Commun ; 457(1): 106-11, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25528587

RESUMO

UNLABELLED: Myostatin (MSTN), a negative regulator of muscle growth and size, is increased after acute myocardial infarction (AMI) but timing of upregulation after injury is not known. In this study, we investigated the timing of the MSTN/AKT/p38 pathway activation in heart and skeletal muscle after AMI, as well as the potential effect of cardiac injury-related MSTN endocrine signaling on skeletal muscle and other circulating growth factors. METHODS: Coronary artery ligation was performed in C57BL/6 mice at age 8 weeks to induce AMI. Mice were sacrificed at different time points (10 m, 1 h, 2 h, 6 h, 12 h, 24 h, 1 week, 2 weeks, 1 months and 2 months) after surgery (n=3 per time point, n=18 total). RESULTS: Cardiac and circulating MSTN upregulation occurred as early as 10 min after AMI. Two months after AMI, increased cardiac MSTN/SMAD2,3 and p38 together with decreased IGF-1/AKT signaling suggest an anti-hypertrophic profile. In skeletal muscle, an absence of local MSTN increase was accompanied by increased MSTN-dependent SMAD2,3 signaling, suggestive of paracrine effects due to cardiac-derived MSTN. Protein degradation by the ubiquitin-proteasome system in the skeletal muscle was also evident. Serum from 24h post-MI mice effectively induced a MSTN-dependent increase in atrogin1 and MuRF1. CONCLUSION: Our study shows that cardiac MTSN activation occurs rapidly after cardiac ischemia and may be involved in peripheral protein degradation in the skeletal muscle by activating atrogin1 and MuRF1.


Assuntos
Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Isquemia Miocárdica/patologia , Miocárdio/metabolismo , Miostatina/metabolismo , Regulação para Cima , Animais , Biomarcadores/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas Musculares/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Isquemia Miocárdica/sangue , Miocárdio/patologia , Miostatina/sangue , Proteínas Ligases SKP Culina F-Box/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Fatores de Tempo , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases/metabolismo
15.
Nucleic Acids Res ; 41(4): e58, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23275548

RESUMO

The mitochondrial genome exists in numerous structural conformations, complicating the study of mitochondrial DNA (mtDNA) metabolism. Here, we describe the development of 2D intact mtDNA agarose gel electrophoresis (2D-IMAGE) for the separation and detection of approximately two-dozen distinct topoisomers. Although the major topoisomers were well conserved across many cell and tissue types, unique differences in certain cells and tissues were also observed. RNase treatment revealed that partially hybridized RNAs associated primarily with covalently closed circular DNA, consistent with this structure being the template for transcription. Circular structures composed of RNA:DNA hybrids contained only heavy-strand DNA sequences, implicating them as lagging-strand replication intermediates. During recovery from replicative arrest, 2D-IMAGE showed changes in both template selection and replication products. These studies suggest that discrete topoisomers are associated with specific mtDNA-directed processes. Because of the increased resolution, 2D-IMAGE has the potential to identify novel mtDNA intermediates involved in replication or transcription, or pathology including oxidative linearization, deletions or depletion.


Assuntos
DNA Mitocondrial/química , Eletroforese em Gel de Ágar/métodos , Genoma Mitocondrial , Animais , Linhagem Celular , Replicação do DNA/efeitos dos fármacos , DNA Topoisomerases/metabolismo , DNA Mitocondrial/isolamento & purificação , DNA Mitocondrial/metabolismo , DNA de Cadeia Simples/análise , DNA de Cadeia Simples/isolamento & purificação , Etídio/farmacologia , Humanos , Camundongos , RNA/química
16.
Cancer Res ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924465

RESUMO

Two recent papers document that responses to immunotherapy are circadian and peak at the end of resting phase (evening) of mice with syngeneic and genetic models of cancers. The circadian effect is attributed to diurnal T cell trafficking through the endothelium on the one hand, and to the circadian expression of PD-L1 on myeloid suppressors on the other. Overall, it appears that tumor immunity as a system, including dendritic cell function, behaves in a circadian manner that is also observed in patients in cancer immunotherapy clinical trials. Importantly, these observations uncover time-of-day as an unforeseen variable for cancer immunotherapy responses. This insight on the immune circadian clock should be further explored to enhance immunotherapy responses in the clinic.

17.
PLoS One ; 19(3): e0288947, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38551970

RESUMO

INTRODUCTION: On June 24, 2022, the U.S. Supreme Court's decision in Dobbs v. Jackson reversed the precedent set forth by Roe v. Wade, empowering individual states to regulate abortion care. This aftermath of this ruling has given rise to widespread bans, limiting the accessibility of abortion services for patients and impeding providers' ability to deliver a comprehensive spectrum of reproductive health services. Of particular concern is the disproportionate impact on medically underserved groups, further heightening existing social and structural disparities in reproductive health. METHODS: We conducted a scoping review to broadly evaluate the clinical and public health impact of Dobbs on patients' access to abortion care and related reproductive health services, in addition to the training and clinical practice of healthcare providers. We searched eight bibliographic databases (PubMed, Scopus, Embase, PsycINFO, Google Scholar, Science Direct, JSTOR, and Web of Science) and three preprint servers (medRxiv, bioRxiv, and Europe PMC) using various combinations of keywords related to 'abortion', 'Dobbs', and 'Roe' on March 22, 2023. Four reviewers independently screened the studies based on pre-specified eligibility criteria and one reviewer performed data extraction for pre-identified themes. The search was conducted based on PRISMA Extension for Scoping Reviews (PRSIMA-ScR) guidelines. RESULTS: Eighteen studies, comprising 12 peer-reviewed articles and 6 study abstracts, met the inclusion criteria. The studies demonstrated that Dobbs increased demand for contraception, magnified existing travel- and cost-related barriers to access, further polarized views on abortion and complex family planning on social media (e.g., Twitter), and evoked substantial concerns among medical trainees regarding their scope of practice and potential legal repercussions for providing abortion care. CONCLUSION: In the wake of Dobbs v. Jackson, further public health and clinical interventions are urgently needed to bridge disparities in abortion care and reproductive health, mitigating the deleterious consequences of this emerging public health crisis.


Assuntos
Pessoal de Saúde , Saúde Pública , Humanos , Feminino , Acessibilidade aos Serviços de Saúde , Gravidez , Estados Unidos , Aborto Induzido/legislação & jurisprudência , Decisões da Suprema Corte , Serviços de Saúde Reprodutiva
18.
Front Pharmacol ; 15: 1387158, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887548

RESUMO

One of the most important developments in psychopharmacology in the past decade has been the emergence of novel treatments for mood disorders, such as psilocybin for treatment-resistant depression. Psilocybin is most commonly found in different species of mushroom; however, the literature on mushroom and fungus extracts with potential antidepressant activity extends well beyond just psilocybin-containing mushrooms, and includes both psychedelic and non-psychedelic species. In the current review, we systematically review the preclinical literature on mushroom and fungus extracts, and their effects of animal models of depression and tests of antidepressant activity. The PICO structure, PRISMA checklist and the Cochrane Handbook for systematic reviews of intervention were used to guide the search strategy. A scoping search was conducted in electronic databases PubMed, CINAHL, Embase and Web of Science. The literature search identified 50 relevant and suitable published studies. These included 19 different species of mushrooms, as well as seven different species of other fungi. Nearly all studies reported antidepressant-like effects of treatment with extracts. Treatments were most commonly delivered orally, in both acute and chronically administered studies to predominantly male rodents. Multiple animal models of depression were used, the most common being unpredictable chronic mild stress, while the tail suspension test and forced swim test were most frequently used as standalone antidepressant screens. Details on each experiment with mushroom and fungus species are discussed in detail, while an evaluation is provided of the strengths and weaknesses of these studies.

19.
Cell Rep Phys Sci ; 5(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38911357

RESUMO

Recreating tissue environments with precise control over mechanical, biochemical, and cellular organization is essential for next-generation tissue models for drug discovery, development studies, and the replication of disease environments. However, controlling these properties at cell-scale lengths remains challenging. Here, we report the development of printing approaches that leverage polyethylene glycol diacrylate (PEGDA) hydrogels containing photocaged oligonucleotides to spatially program material characteristics with non-destructive, non-ultraviolet light. We further integrate this system with a perfusion chamber to allow us to alter the composition of PEGDA hydrogels while retaining common light-activatable photocaged DNAs. We demonstrate that the hydrogels can capture DNA functionalized materials, including cells coated with complementary oligonucleotides with spatial control using biocompatible wavelengths. Overall, these materials open pathways to orthogonal capture of any DNA functionalized materials while not changing the sequences of the DNA.

20.
bioRxiv ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39091842

RESUMO

Meniscus injuries pose significant challenges in clinical settings, primarily due to the intrinsic heterogeneity of the tissue and the limited efficacy of current treatments. Endogenous cell migration is crucial for the healing process, yet the regulatory mechanisms of meniscus cell migration and its zonal dependency within the meniscus are not fully understood. Thus, this study investigates the role of epigenetic mechanisms in governing meniscus cell migration under inflammatory conditions, with a focus on their implications for injury healing and regeneration. Here, we discovered that a proinflammatory cytokine, TNF-α treatment significantly impedes the migration speed of inner meniscus cells, while outer meniscus cells are unaffected, underscoring a zonal-dependent response within the meniscus. Our analysis identified distinct histone modification patterns and chromatin dynamics between inner and outer meniscus cells during migration, highlighting the necessity to consider these zonal-dependent properties in devising repair strategies. Specifically, we found that TNF-α differentially influences histone modifications, particularly H3K27me3, between the two cell types. Transcriptome analysis further revealed that TNF-α treatment induces substantial gene expression changes, with inner meniscus cells exhibiting more pronounced alterations than outer cells. Gene cluster analysis pointed to distinct responses in chromatin remodeling, extracellular matrix assembly, and wound healing processes between the zonal cell populations. Moreover, we identified potential therapeutic targets by employing existing epigenetic drugs, GSKJ4 (a histone demethylase inhibitor) and C646 (a histone acetyltransferase inhibitor), to successfully restore the migration speed of inner meniscus cells under inflammatory conditions. This highlights their potential utility in treating meniscus tear injuries. Overall, our findings elucidate the intricate interplay between epigenetic mechanisms and meniscus cell migration, along with its meniscus zonal dependency. This study provides insights into potential targets for enhancing meniscus repair and regeneration, which may lead to improved clinical outcomes for patients with meniscus injuries and osteoarthritis.

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