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1.
Simul Healthc ; 13(6): 376-386, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30407958

RESUMO

INTRODUCTION: Protocolized automation of critical, labor-intensive tasks for out-of-hospital cardiac arrest (OHCA) resuscitation may decrease Emergency Medical Services (EMS) provider workload. A simulation-based assessment method incorporating objective and self-reported metrics was developed and used to quantify workloads associated with standard and experimental approaches to OHCA resuscitation. METHODS: Emergency Medical Services-Basic (EMT-B) and advanced life support (ALS) providers were randomized into two-provider mixed-level teams and fitted with heart rate (HR) monitors for continuous HR and energy expenditure (EE) monitoring. Subjects' resting salivary α-amylase (sAA) levels were measured along with Borg perceived exertion scores and multidimensional workload assessments (NASA-TLX). Each team engaged in the following three OHCA simulations: (1) baseline simulation in standard BLS/ALS roles; (2) repeat simulation in standard roles; and then (3) repeat simulation in reversed roles, ie, EMT-B provider performing ALS tasks. Control teams operated with standard state protocols and equipment; experimental teams used resuscitation-automating devices and accompanying goal-directed algorithmic protocol for simulations 2 and 3. Investigators video-recorded resuscitations and analyzed subjects' percent attained of maximal age-predicted HR (%mHR), EE, sAA, Borg, and NASA-TLX measurements. RESULTS: Ten control and ten experimental teams completed the study (20 EMT-Basic; 1 EMT-Intermediate, 8 EMT-Cardiac, 11 EMT-Paramedic). Median %mHR, EE, sAA, Borg, and NASA-TLX scores did not differ between groups at rest. Overall multivariate analyses of variance did not detect significant differences; univariate analyses of variance for changes in %mHR, Borg, and NASA-TLX from resting state detected significant differences across simulations (workload reductions in experimental groups for simulations 2 and 3). CONCLUSIONS: A simulation-based OHCA resuscitation performance and workload assessment method compared protocolized automation-assisted resuscitation with standard response. During exploratory application of the assessment method, subjects using the experimental approach appeared to experience reduced levels of physical exertion and perceived workload than control subjects.


Assuntos
Reanimação Cardiopulmonar/normas , Serviços Médicos de Emergência/normas , Auxiliares de Emergência/educação , Medicina de Emergência/educação , Parada Cardíaca Extra-Hospitalar/terapia , Simulação de Paciente , Carga de Trabalho , Humanos , Gravação em Vídeo
2.
Simul Healthc ; 11(6): 365-375, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27509064

RESUMO

INTRODUCTION: Effective resuscitation of out-of-hospital cardiac arrest (OHCA) patients is challenging. Alternative resuscitative approaches using electromechanical adjuncts may improve provider performance. Investigators applied simulation to study the effect of an experimental automation-assisted, goal-directed OHCA management protocol on EMS providers' resuscitation performance relative to standard protocols and equipment. METHODS: Two-provider (emergency medical technicians (EMT)-B and EMT-I/C/P) teams were randomized to control or experimental group. Each team engaged in 3 simulations: baseline simulation (standard roles); repeat simulation (standard roles); and abbreviated repeat simulation (reversed roles, i.e., basic life support provider performing ALS tasks). Control teams used standard OHCA protocols and equipment (with high-performance cardiopulmonary resuscitation training intervention); for second and third simulations, experimental teams performed chest compression, defibrillation, airway, pulmonary ventilation, vascular access, medication, and transport tasks with goal-directed protocol and resuscitation-automating devices. Videorecorders and simulator logs collected resuscitation data. RESULTS: Ten control and 10 experimental teams comprised 20 EMT-B's; 1 EMT-I, 8 EMT-C's, and 11 EMT-P's; study groups were not fully matched. Both groups suboptimally performed chest compressions and ventilations at baseline. For their second simulations, control teams performed similarly except for reduced on-scene time, and experimental teams improved their chest compressions (P=0.03), pulmonary ventilations (P<0.01), and medication administration (P=0.02); changes in their performance of chest compression, defibrillation, airway, and transport tasks did not attain significance against control teams' changes. Experimental teams maintained performance improvements during reversed-role simulations. CONCLUSION: Simulation-based investigation into OHCA resuscitation revealed considerable variability and improvable deficiencies in small EMS teams. Goal-directed, automation-assisted OHCA management augmented select resuscitation bundle element performance without comprehensive improvement.


Assuntos
Automação , Reanimação Cardiopulmonar/educação , Auxiliares de Emergência/educação , Parada Cardíaca Extra-Hospitalar , Treinamento por Simulação , Adulto , Reanimação Cardiopulmonar/instrumentação , Reanimação Cardiopulmonar/métodos , Serviços Médicos de Emergência , Feminino , Humanos , Masculino , Adulto Jovem
3.
Bioorg Med Chem ; 14(10): 3491-5, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16434201

RESUMO

A series of novel chalcones and bis-chalcones containing boronic acid moieties has been synthesized and evaluated for antitumor activity against the human breast cancer MDA-MB-231 (estrogen receptor-negative) and MCF7 (estrogen receptor-positive) cell lines and against two normal breast epithelial cell lines, MCF-10A and MCF-12A. These molecules inhibited the growth of the human breast cancer cell lines at low micromolar to nanomolar concentrations, with five of them (1-4, 9) showing preferential inhibition of the human breast cancer cell lines. Furthermore, bis-chalcone 8 exhibited a more potent inhibition of colon cancer cells expressing wild-type p53 than of an isogenic cell line that was p53-null.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Ácidos Borônicos/química , Ácidos Borônicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Calônios/química , Calônios/farmacologia , Neoplasias do Colo/tratamento farmacológico , Piperidinas/química , Piperidinas/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Dose Letal Mediana , Estrutura Molecular
4.
J Biol Chem ; 280(33): 29519-24, 2005 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-15965230

RESUMO

Protein phosphatase 2A (PP2A) is a ubiquitously expressed member of the serine-threonine phosphatase family that is involved in regulation of many cellular processes including transcription, translation, cellular metabolism, and apoptosis. Because of a correlation between PP2A and estrogen receptor alpha (ER) expression in several human breast cancer cell lines, the effect of PP2A on regulation of ER expression in the human breast cancer cell line MCF-7 was studied. Inhibition of PP2A using the pharmacologic inhibitor okadaic acid at 250 nm for 16 h resulted in a 60% reduction in PP2A activity in MCF-7 cells concurrent with a 75% reduction in ER mRNA and protein expression. Similar results were obtained with a small interfering RNA probe that specifically inhibited PP2A expression. ER promoter studies showed that regulation of ER through the PP2A pathway did not occur through transcriptional activation. Rather, PP2A mediated ER expression through modulation of ER mRNA stability through degradation of ER mRNA, reversible with concomitant treatment with the proteasomal inhibitor MG 132. These data suggest a novel pathway controlling ER expression resulting from the activation of PP2A, potentially providing a novel therapeutic target.


Assuntos
Receptor alfa de Estrogênio/genética , Regulação da Expressão Gênica , Fosfoproteínas Fosfatases/fisiologia , RNA Mensageiro/metabolismo , Regiões 3' não Traduzidas/fisiologia , Linhagem Celular Tumoral , Humanos , Ácido Okadáico/farmacologia , Regiões Promotoras Genéticas , Complexo de Endopeptidases do Proteassoma/fisiologia , Proteína Fosfatase 2 , RNA Interferente Pequeno/farmacologia
5.
Cancer Biol Ther ; 3(12): 1304-12, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15662126

RESUMO

Absence of the estrogen receptor alpha (ER) in human breast cancer cells is an indicator of poor prognosis, and predictive of lack of response to hormonal therapy. Previous studies in our laboratory and others have shown that epigenetic regulation, including DNA methylation and histone deacetylation, are common mechanisms leading to ER gene silencing. Through the use of pharmacologic inhibitors, 5-aza 2'deoxycytidine (AZA) and Trichostatin A (TSA), we have shown that alterations in both of these mechanisms results in synergistic reexpression of ER mRNA and functional protein. These alterations may play a larger role in stimulation of cell signaling pathways leading to ER expression. We have utilized newly developed genome wide screening microarray techniques to identify gene(s) contributing to the hormone independent phenotype and AZA/TSA mediated ER expression. From this screen, we identified and confirmed expression of 4 candidate genes (PP2A, XCL1, THY1 and NBC4) as potential regulators of the hormone independent phenotype. Expression of two genes, XCL1 and PP2A, appeared to be correlated with ER expression. PP2A expression was not changed with ER degradation using ICI 182,780 whereas XCL1 expression decreased in the presence of AZA/TSA and ICI 182,780. This suggests that PP2A may be a determinant of ER expression while XCL1 appears to be ER responsive and downstream of ER expression. These gene products may be novel targets to be further explored in the development of new therapeutics for ER negative breast cancer.


Assuntos
Azacitidina/análogos & derivados , Neoplasias da Mama/genética , Metilação de DNA , Epigênese Genética , Receptor alfa de Estrogênio/genética , Linfocinas/genética , Fosfoproteínas Fosfatases/genética , Sialoglicoproteínas/genética , Acetilação/efeitos dos fármacos , Azacitidina/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Quimiocinas C , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Receptor alfa de Estrogênio/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases , Humanos , Ácidos Hidroxâmicos , Linfocinas/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fosfoproteínas Fosfatases/metabolismo , Proteína Fosfatase 2 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sialoglicoproteínas/metabolismo , Células Tumorais Cultivadas
6.
Breast Cancer Res Treat ; 81(3): 177-86, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14620913

RESUMO

Epigenetic mechanisms, such as DNA methylation and histone deacetylation, may play a role in loss of estrogen receptor alpha (ER) expression in ER negative human breast cancer cells. Our previous studies showed that pharmacologic inhibition of these mechanisms using the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (AZA), and the histone deacetylase (HDAC) inhibitor, Trichostatin A (TSA), resulted in expression of functional ER mRNA and protein. Therefore, we sought to characterize the effects of a recently described HDAC inhibitor, Scriptaid, on cell growth and ER expression and function in ER negative human breast cancer cell lines. Scriptaid treatment of three ER negative cell lines, MDA-MB-231, MDA-MB-435 and Hs578t, resulted in significant growth inhibition and increased acetylation of H3 and H4 histone tails. Quantitative Real Time PCR showed 2000-20,000-fold increase of ER mRNA transcript in all three cell lines after 48 h of Scriptaid treatment. Further, dose dependent re-expression of an estrogen responsive gene, the progesterone receptor (PR), indicated that induced ER is functional. As seen with TSA and AZA, Scriptaid and AZA co-treatment was more effective in inducing ER than Scriptaid or AZA alone. In vivo analysis using a xenograft mouse model bearing MDA-MB-231 tumors showed decreased tumor growth following Scriptaid or TSA treatment. Our results indicate that the novel HDAC inhibitor, Scriptaid, inhibits tumor growth in vitro and in vivo and, in conjunction with AZA, acts to re-express functional ER. These data suggest that Scriptaid or related HDAC inhibitors are candidates for further study in breast cancer.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Neoplasias da Mama/enzimologia , Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Hidroxilaminas/farmacologia , Quinolinas/farmacologia , Receptores de Estrogênio/efeitos dos fármacos , Acetilação/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Divisão Celular/efeitos dos fármacos , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Receptor alfa de Estrogênio , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Concentração Inibidora 50 , RNA Mensageiro/análise , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/efeitos dos fármacos , Células Tumorais Cultivadas/citologia
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