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1.
Development ; 149(20)2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36039869

RESUMO

Bud tip progenitors (BTPs) in the developing lung give rise to all epithelial cell types found in the airways and alveoli. This work aimed to develop an iPSC organoid model enriched with NKX2-1+ BTP-like cells. Building on previous studies, we optimized a directed differentiation paradigm to generate spheroids with more robust NKX2-1 expression. Spheroids were expanded into organoids that possessed NKX2-1+/CPM+ BTP-like cells, which increased in number over time. Single cell RNA-sequencing analysis revealed a high degree of transcriptional similarity between induced BTPs (iBTPs) and in vivo BTPs. Using FACS, iBTPs were purified and expanded as induced bud tip progenitor organoids (iBTOs), which maintained an enriched population of bud tip progenitors. When iBTOs were directed to differentiate into airway or alveolar cell types using well-established methods, they gave rise to organoids composed of organized airway or alveolar epithelium, respectively. Collectively, iBTOs are transcriptionally and functionally similar to in vivo BTPs, providing an important model for studying human lung development and differentiation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Fator Nuclear 1 de Tireoide/metabolismo , Células Epiteliais Alveolares , Diferenciação Celular , Humanos , Pulmão , Organoides
2.
Am J Physiol Lung Cell Mol Physiol ; 323(3): L341-L354, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35762622

RESUMO

The 9th biennial conference titled "Stem Cells, Cell Therapies, and Bioengineering in Lung Biology and Diseases" was hosted virtually, due to the ongoing COVID-19 pandemic, in collaboration with the University of Vermont Larner College of Medicine, the National Heart, Lung, and Blood Institute, the Alpha-1 Foundation, the Cystic Fibrosis Foundation, and the International Society for Cell & Gene Therapy. The event was held from July 12th through 15th, 2021 with a pre-conference workshop held on July 9th. As in previous years, the objectives remained to review and discuss the status of active research areas involving stem cells (SCs), cellular therapeutics, and bioengineering as they relate to the human lung. Topics included 1) technological advancements in the in situ analysis of lung tissues, 2) new insights into stem cell signaling and plasticity in lung remodeling and regeneration, 3) the impact of extracellular matrix in stem cell regulation and airway engineering in lung regeneration, 4) differentiating and delivering stem cell therapeutics to the lung, 5) regeneration in response to viral infection, and 6) ethical development of cell-based treatments for lung diseases. This selection of topics represents some of the most dynamic and current research areas in lung biology. The virtual workshop included active discussion on state-of-the-art methods relating to the core features of the 2021 conference, including in situ proteomics, lung-on-chip, induced pluripotent stem cell (iPSC)-airway differentiation, and light sheet microscopy. The conference concluded with an open discussion to suggest funding priorities and recommendations for future research directions in basic and translational lung biology.


Assuntos
COVID-19 , Células-Tronco Pluripotentes Induzidas , Bioengenharia , Biologia , COVID-19/terapia , Humanos , Pulmão , Pandemias
3.
BMC Genomics ; 20(Suppl 8): 549, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31307398

RESUMO

BACKGROUND: By definition, effect of synonymous single-nucleotide variants (SNVs) on protein folding and function are neutral, as they alter the codon and not the encoded amino acid. Recent examples indicate tissue-specific and transfer RNA (tRNA)-dependent effects of some genetic variations arguing against neutrality of synonymous SNVs for protein biogenesis. RESULTS: We performed systematic analysis of tRNA abunandance across in various models used in cystic fibrosis (CF) research and drug development, including Fischer rat thyroid (FRT) cells, patient-derived primary human bronchial epithelia (HBE) from lung biopsies, primary human nasal epithelia (HNE) from nasal curettage, intestinal organoids, and airway progenitor-directed differentiation of human induced pluripotent stem cells (iPSCs). These were compared to an immortalized CF bronchial cell model (CFBE41o-) and two widely used laboratory cell lines, HeLa and HEK293. We discovered that specific synonymous SNVs exhibited differential effects which correlated with variable concentrations of cognate tRNAs. CONCLUSIONS: Our results highlight ways in which the presence of synonymous SNVs may alter local kinetics of mRNA translation; and thus, impact protein biogenesis and function. This effect is likely to influence results from mechansistic analysis and/or drug screeining efforts, and establishes importance of cereful model system selection based on genetic variation profile.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/métodos , Polimorfismo de Nucleotídeo Único , RNA de Transferência/genética , Códon/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Genótipo , Células HEK293 , Células HeLa , Humanos , Fenótipo
4.
Epilepsia ; 60(6): 1045-1053, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31087652

RESUMO

The revolution in high-throughput omics technologies has dramatically expanded our understanding of the epilepsies as complex diseases. It is now clear that further progress in treating the full spectrum of seizure disorders requires a systems-level framework for analyzing and integrating data from multiple omics technologies that moves beyond the search for single molecular alterations to an understanding of dysregulated pathways in epilepsy. Taking such a pathway-centered view requires further integrating the tools of systems biology into epilepsy research. In this appraisal, we highlight and summarize systems biology approaches in basic epilepsy studies as they were discussed during the 2017 Workshop on the Neurobiology of Epilepsy (WONOEP). During the 3-day event, participants exchanged emerging results and thoughts on developing the systems biology of epilepsy, and the promise and limitations of these approaches for the near term.


Assuntos
Epilepsia/genética , Biologia de Sistemas/métodos , Epilepsia/fisiopatologia , Genômica , Humanos , Neurobiologia , Proteômica
5.
Ecol Appl ; 29(4): e01881, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30939226

RESUMO

The development and expansion of wind energy is considered a key global threat to bat populations. Bat carcasses are being found underneath wind turbines across North and South America, Eurasia, Africa, and the Austro-Pacific. However, relatively little is known about the comparative impacts of techniques designed to modify turbine operations in ways that reduce bat fatalities associated with wind energy facilities. This study tests a novel approach for reducing bat fatalities and curtailment time at a wind energy facility in the United States, then compares these results to operational mitigation techniques used at other study sites in North America and Europe. The study was conducted in Wisconsin during 2015 using a new system of tools for analyzing bat activity and wind speed data to make near real-time curtailment decisions when bats are detected in the area at control turbines (N = 10) vs. treatment turbines (N = 10). The results show that this smart curtailment approach (referred to as Turbine Integrated Mortality Reduction, TIMR) significantly reduced fatality estimates for treatment turbines relative to control turbines for pooled species data, and for each of five species observed at the study site: pooled data (-84.5%); eastern red bat (Lasiurus borealis, -82.5%); hoary bat (Lasiurus cinereus, -81.4%); silver-haired bat (Lasionycteris noctivagans, -90.9%); big brown bat (Eptesicus fuscus, -74.2%); and little brown bat (Myotis lucifugus, -91.4%). The approach reduced power generation and estimated annual revenue at the wind energy facility by ≤ 3.2% for treatment turbines relative to control turbines, and we estimate that the approach would have reduced curtailment time by 48% relative to turbines operated under a standard curtailment rule used in North America. This approach significantly reduced fatalities associated with all species evaluated, each of which has broad distributions in North America and different ecological affinities, several of which represent species most affected by wind development in North America. While we recognize that this approach needs to be validated in other areas experiencing rapid wind energy development, we anticipate that this approach has the potential to significantly reduce bat fatalities in other ecoregions and with other bat species assemblages in North America and beyond.


Assuntos
Quirópteros , África , Animais , Europa (Continente) , América do Norte , Wisconsin
7.
Development ; 142(2): 258-67, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25564622

RESUMO

Basal cells are multipotent airway progenitors that generate distinct epithelial cell phenotypes crucial for homeostasis and repair of the conducting airways. Little is known about how these progenitor cells expand and transition to differentiation to form the pseudostratified airway epithelium in the developing and adult lung. Here, we show by genetic and pharmacological approaches that endogenous activation of Notch3 signaling selectively controls the pool of undifferentiated progenitors of upper airways available for differentiation. This mechanism depends on the availability of Jag1 and Jag2, and is key to generating a population of parabasal cells that later activates Notch1 and Notch2 for secretory-multiciliated cell fate selection. Disruption of this mechanism resulted in aberrant expansion of basal cells and altered pseudostratification. Analysis of human lungs showing similar abnormalities and decreased NOTCH3 expression in subjects with chronic obstructive pulmonary disease suggests an involvement of NOTCH3-dependent events in the pathogenesis of this condition.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular/fisiologia , Células Epiteliais/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pulmão/embriologia , Proteínas de Membrana/metabolismo , Receptores Notch/metabolismo , Mucosa Respiratória/embriologia , Transdução de Sinais/fisiologia , Animais , Western Blotting , Técnicas de Cultura de Células , Imunofluorescência , Humanos , Imuno-Histoquímica , Hibridização In Situ , Proteína Jagged-1 , Camundongos , Microscopia Confocal , Reação em Cadeia da Polimerase em Tempo Real , Receptor Notch3 , Mucosa Respiratória/citologia , Proteínas Serrate-Jagged , Especificidade da Espécie
8.
Chaos ; 28(1): 013129, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29390612

RESUMO

Fronts propagating in two-dimensional advection-reaction-diffusion systems exhibit a rich topological structure. When the underlying fluid flow is periodic in space and time, the reaction front can lock to the driving frequency. We explain this mode-locking phenomenon using the so-called burning invariant manifolds (BIMs). In fact, the mode-locked profile is delineated by a BIM attached to a relative periodic orbit (RPO) of the front element dynamics. Changes in the type (and loss) of mode-locking can be understood in terms of local and global bifurcations of the RPOs and their BIMs. We illustrate these concepts numerically using a chain of alternating vortices in a channel geometry.

9.
Chaos ; 28(1): 013109, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29390624

RESUMO

Understanding the generative mechanism of a natural system is a vital component of the scientific method. Here, we investigate one of the fundamental steps toward this goal by presenting the minimal generator of an arbitrary binary Markov process. This is a class of processes whose predictive model is well known. Surprisingly, the generative model requires three distinct topologies for different regions of parameter space. We show that a previously proposed generator for a particular set of binary Markov processes is, in fact, not minimal. Our results shed the first quantitative light on the relative (minimal) costs of prediction and generation. We find, for instance, that the difference between prediction and generation is maximized when the process is approximately independently, identically distributed.

10.
Genes Dev ; 24(19): 2194-204, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20837658

RESUMO

Glioblastoma multiforme (GBM) is a lethal brain tumor characterized by intense apoptosis resistance and extensive necrosis. Bcl2L12 (for Bcl2-like 12) is a cytoplasmic and nuclear protein that is overexpressed in primary GBM and functions to inhibit post-mitochondrial apoptosis signaling. Here, we show that nuclear Bcl2L12 physically and functionally interacts with the p53 tumor suppressor, as evidenced by the capacity of Bcl2L12 to (1) enable bypass of replicative senescence without concomitant loss of p53 or p19 (Arf), (2) inhibit p53-dependent DNA damage-induced apoptosis, (3) impede the capacity of p53 to bind some of its target gene promoters, and (4) attenuate endogenous p53-directed transcriptomic changes following genotoxic stress. Correspondingly, The Cancer Genome Atlas profile and tissue protein analyses of human GBM specimens show significantly lower Bcl2L12 expression in the setting of genetic p53 pathway inactivation. Thus, Bcl2L12 is a multifunctional protein that contributes to intense therapeutic resistance of GBM through its ability to operate on two key nodes of cytoplasmic and nuclear signaling cascades.


Assuntos
Regulação da Expressão Gênica , Glioma/fisiopatologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/fisiologia , Linhagem Celular , Células Cultivadas , Senescência Celular/fisiologia , Dano ao DNA , Humanos , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica , Estabilidade Proteica , Transporte Proteico , Transdução de Sinais
11.
Nature ; 470(7334): 359-65, 2011 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21307849

RESUMO

Telomere dysfunction activates p53-mediated cellular growth arrest, senescence and apoptosis to drive progressive atrophy and functional decline in high-turnover tissues. The broader adverse impact of telomere dysfunction across many tissues including more quiescent systems prompted transcriptomic network analyses to identify common mechanisms operative in haematopoietic stem cells, heart and liver. These unbiased studies revealed profound repression of peroxisome proliferator-activated receptor gamma, coactivator 1 alpha and beta (PGC-1α and PGC-1ß, also known as Ppargc1a and Ppargc1b, respectively) and the downstream network in mice null for either telomerase reverse transcriptase (Tert) or telomerase RNA component (Terc) genes. Consistent with PGCs as master regulators of mitochondrial physiology and metabolism, telomere dysfunction is associated with impaired mitochondrial biogenesis and function, decreased gluconeogenesis, cardiomyopathy, and increased reactive oxygen species. In the setting of telomere dysfunction, enforced Tert or PGC-1α expression or germline deletion of p53 (also known as Trp53) substantially restores PGC network expression, mitochondrial respiration, cardiac function and gluconeogenesis. We demonstrate that telomere dysfunction activates p53 which in turn binds and represses PGC-1α and PGC-1ß promoters, thereby forging a direct link between telomere and mitochondrial biology. We propose that this telomere-p53-PGC axis contributes to organ and metabolic failure and to diminishing organismal fitness in the setting of telomere dysfunction.


Assuntos
Mitocôndrias/metabolismo , Mitocôndrias/patologia , Telômero/metabolismo , Telômero/patologia , Trifosfato de Adenosina/biossíntese , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Proliferação de Células , DNA Mitocondrial/análise , Doxorrubicina/toxicidade , Gluconeogênese , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Fígado/citologia , Fígado/metabolismo , Camundongos , Miocárdio/citologia , Miocárdio/metabolismo , RNA/genética , Espécies Reativas de Oxigênio/metabolismo , Telomerase/deficiência , Telomerase/genética , Telômero/enzimologia , Telômero/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
Cancer ; 121(7): 1025-31, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25417775

RESUMO

BACKGROUND: Bevacizumab is associated with an increased risk of arterial thromboembolism (ATE); however, its effect on venous thromboembolism (VTE) remains controversial. Scant data exist on the factors that increase the risk of ATE/VTE in patients with prostate cancer. The authors investigated the association of bevacizumab treatment and clinical factors with ATE/VTE risk in patients who were treated on Cancer and Leukemia Group B (CALGB) trial 90401. METHODS: Patients with metastatic, castration-resistant prostate cancer were randomized to receive docetaxel and prednisone with or without bevacizumab once every 21 days. Cycle-to-event Cox regression models were used to investigate the association of bevacizumab with the incidence of grade 3 or greater (≥ 3) ATE and VTE. Age, prior ATE/VTE, baseline antiplatelet/anticoagulant use, and VTE risk score (based on leukocyte count, hemoglobin, platelet count, body mass index, and tumor location) were evaluated in univariate and multivariable analyses. RESULTS: Of 1008 randomized patients, the odds of experiencing grade ≥ 3 ATE were significantly greater in those who received bevacizumab compared with those who received placebo (odds ratio, 2.79; P = .02), whereas an opposite trend was noted for grade ≥ 3 VTE (odds ratio, 0.60; P = .08). In the multivariable analysis, bevacizumab treatment (hazard ratio [HR], 3.00; P = .01) and age (HR, 1.06; P = .02) were significantly associated with the risk of ATE; whereas age (HR, 1.05; P = .01) and VTE risk score (HR, 1.83; P = .03) were significantly associated with the risk of VTE. CONCLUSIONS: Bevacizumab was significantly associated with a greater risk of ATE in patients with metastatic, castration-resistant prostate cancer, but it was not significantly associated with the risk of VTE. Understanding clinical factors that increase the risk for experiencing ATE/VTE is essential to mitigate the risks and reduce the burden of these prevalent complications in cancer care.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Artérias/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Tromboembolia/etiologia , Tromboembolia Venosa/etiologia , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Ensaios Clínicos Fase III como Assunto , Docetaxel , Método Duplo-Cego , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prednisona/administração & dosagem , Prognóstico , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/secundário , Taxa de Sobrevida , Taxoides/administração & dosagem , Tromboembolia/classificação
13.
Chaos ; 25(8): 087404, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26328575

RESUMO

Recent theoretical and experimental investigations have demonstrated the role of certain invariant manifolds, termed burning invariant manifolds (BIMs), as one-way dynamical barriers to reaction fronts propagating within a flowing fluid. These barriers form one-dimensional curves in a two-dimensional fluid flow. In prior studies, the fluid velocity field was required to be either time-independent or time-periodic. In the present study, we develop an approach to identify prominent one-way barriers based only on fluid velocity data over a finite time interval, which may have arbitrary time-dependence. We call such a barrier a burning Lagrangian coherent structure (bLCS) in analogy to Lagrangian coherent structures (LCSs) commonly used in passive advection. Our approach is based on the variational formulation of LCSs using curves of stationary "Lagrangian shear," introduced by Farazmand et al. [Physica D 278-279, 44 (2014)] in the context of passive advection. We numerically validate our technique by demonstrating that the bLCS closely tracks the BIM for a time-independent, double-vortex channel flow with an opposing "wind."

14.
Cancer ; 120(7): 976-82, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24339028

RESUMO

BACKGROUND: Polo-like kinases (Plks) control multiple steps during the cell cycle, and Plk1 is overexpressed in urothelial cancer (UC). Volasertib (BI 6727), a Plk inhibitor, has demonstrated antitumor activity in several malignancies, including UC. In this phase 2 trial, the authors investigated volasertib as a second-line treatment in advanced/metastatic UC. METHODS: Patients who progressed within 2 years of 1 prior chemotherapy regimen received 300 mg volasertib on day 1 every 3 weeks. The dose was escalated to 350 mg in cycle 2 if volasertib was tolerated in cycle 1. The primary endpoint was tumor response, which was assessed every 6 weeks; secondary endpoints were progression-free survival, overall survival, duration of response, safety, and pharmacokinetics. RESULTS: Fifty patients were enrolled, and the median patient age was 68.5 years (range, 52-83 years). All patients had received prior platinum, 94% of patients had relapsed ≤2 years after prior therapy, 36% had liver metastases, and 54% had lung metastases. The median number of treatment cycles was 2 (range, 1-27 treatment cycles), and 23 patients were dose escalated at cycle 2. Seven patients (14%) had a partial response, 13 (26%) had stable disease, and 30 (60%) progressed within 6 weeks. The median response duration was 41 weeks (range, 29.1-77.3 weeks). The median progression-free survival was 1.4 months, and the median overall survival was 8.5 months. The most frequent grade 3 and 4 adverse events were neutropenia (28%), thrombocytopenia (20%), and anemia (16%). No cumulative toxicity was observed. CONCLUSIONS: Volasertib as second-line treatment for advanced/metastatic UC had an acceptable safety profile but demonstrated insufficient antitumor activity for further evaluation as a monotherapy.


Assuntos
Pteridinas/uso terapêutico , Neoplasias Urológicas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pteridinas/farmacocinética , Resultado do Tratamento , Neoplasias Urológicas/enzimologia , Neoplasias Urológicas/metabolismo , Neoplasias Urológicas/patologia
15.
Mol Genet Metab ; 112(1): 9-16, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24667082

RESUMO

For pregnant women with phenylketonuria (PKU), maintaining blood phenylalanine (Phe)<360µmol/L is critical due to the toxicity of elevated Phe to the fetus. Sapropterin dihydrochloride (sapropterin) lowers blood Phe in tetrahydrobiopterin (BH4) responsive patients with PKU, in conjunction with a Phe-restricted diet, but clinical evidence supporting its use during pregnancy is limited. As of June 3, 2013, the Maternal Phenylketonuria Observational Program (PKU MOMS) sub-registry contained data from 21 pregnancies - in women with PKU who were treated with sapropterin either before (N=5) or during (N=16) pregnancy. Excluding data for spontaneous abortions (N=4), the data show that the mean of median blood Phe [204.7±126.6µmol/L (n=14)] for women exposed to sapropterin during pregnancy was 23% lower, and had a 58% smaller standard deviation, compared to blood Phe [267.4±300.7µmol/L (n=3)] for women exposed to sapropterin prior to pregnancy. Women on sapropterin during pregnancy experienced fewer blood Phe values above the recommended 360µmol/L threshold. When median blood Phe concentration was <360µmol/L throughout pregnancy, 75% (12/16) of pregnancy outcomes were normal compared to 40% (2/5) when median blood Phe was >360µmol/L. Severe adverse events identified by the investigators as possibly related to sapropterin use were premature labor (N=1) and spontaneous abortion (N=1) for the women and hypophagia for the offspring [premature birth (35w4d), N=1]. One congenital malformation (cleft palate) of unknown etiology was reported as unrelated to sapropterin. Although there is limited information regarding the use of sapropterin during pregnancy, these sub-registry data show that sapropterin was generally well-tolerated and its use during pregnancy was associated with lower mean blood Phe. Because the teratogenicity of elevated maternal blood Phe is without question, sapropterin should be considered as a treatment option in pregnant women with PKU who cannot achieve recommended ranges of blood Phe with dietary therapy alone.


Assuntos
Biopterinas/análogos & derivados , Fenilalanina/sangue , Fenilcetonúria Materna/tratamento farmacológico , Aborto Espontâneo/induzido quimicamente , Adulto , Biopterinas/administração & dosagem , Biopterinas/efeitos adversos , Feminino , Humanos , Trabalho de Parto Prematuro/induzido quimicamente , Fenilcetonúria Materna/dietoterapia , Gravidez , Resultado da Gravidez , Adulto Jovem
16.
J Sport Exerc Psychol ; 36(3): 281-92, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24918311

RESUMO

We argue that basic psychological needs theory (BPNT) offers impetus to the value of mental toughness as a mechanism for optimizing human functioning. We hypothesized that psychological needs satisfaction (thwarting) would be associated with higher (lower) levels of mental toughness, positive affect, and performance and lower (higher) levels of negative affect. We also expected that mental toughness would be associated with higher levels of positive affect and performance and lower levels of negative affect. Further, we predicted that coaching environments would be related to mental toughness indirectly through psychological needs and that psychological needs would indirectly relate with performance and affect through mental toughness. Adolescent cross-country runners (136 male and 85 female, M(age) = 14.36) completed questionnaires pertaining to BPNT variables, mental toughness, and affect. Race times were also collected. Our findings supported our hypotheses. We concluded that BPNT is generative in understanding some of the antecedents and consequences of mental toughness and is a novel framework useful for understanding mental toughness.


Assuntos
Adaptação Psicológica , Desempenho Atlético/psicologia , Motivação , Esportes/psicologia , Adolescente , Afeto , Feminino , Humanos , Masculino , Testes Psicológicos , Inquéritos e Questionários , Atletismo/psicologia
17.
BMJ ; 384: e075847, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355154

RESUMO

OBJECTIVE: To identify the optimal dose and modality of exercise for treating major depressive disorder, compared with psychotherapy, antidepressants, and control conditions. DESIGN: Systematic review and network meta-analysis. METHODS: Screening, data extraction, coding, and risk of bias assessment were performed independently and in duplicate. Bayesian arm based, multilevel network meta-analyses were performed for the primary analyses. Quality of the evidence for each arm was graded using the confidence in network meta-analysis (CINeMA) online tool. DATA SOURCES: Cochrane Library, Medline, Embase, SPORTDiscus, and PsycINFO databases. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Any randomised trial with exercise arms for participants meeting clinical cut-offs for major depression. RESULTS: 218 unique studies with a total of 495 arms and 14 170 participants were included. Compared with active controls (eg, usual care, placebo tablet), moderate reductions in depression were found for walking or jogging (n=1210, κ=51, Hedges' g -0.62, 95% credible interval -0.80 to -0.45), yoga (n=1047, κ=33, g -0.55, -0.73 to -0.36), strength training (n=643, κ=22, g -0.49, -0.69 to -0.29), mixed aerobic exercises (n=1286, κ=51, g -0.43, -0.61 to -0.24), and tai chi or qigong (n=343, κ=12, g -0.42, -0.65 to -0.21). The effects of exercise were proportional to the intensity prescribed. Strength training and yoga appeared to be the most acceptable modalities. Results appeared robust to publication bias, but only one study met the Cochrane criteria for low risk of bias. As a result, confidence in accordance with CINeMA was low for walking or jogging and very low for other treatments. CONCLUSIONS: Exercise is an effective treatment for depression, with walking or jogging, yoga, and strength training more effective than other exercises, particularly when intense. Yoga and strength training were well tolerated compared with other treatments. Exercise appeared equally effective for people with and without comorbidities and with different baseline levels of depression. To mitigate expectancy effects, future studies could aim to blind participants and staff. These forms of exercise could be considered alongside psychotherapy and antidepressants as core treatments for depression. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018118040.


Assuntos
Depressão , Transtorno Depressivo Maior , Humanos , Metanálise em Rede , Depressão/terapia , Transtorno Depressivo Maior/terapia , Teorema de Bayes , Exercício Físico , Antidepressivos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Cancer ; 119(20): 3636-43, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23913744

RESUMO

BACKGROUND: Preliminary data suggest a potential decreased benefit of docetaxel in patients with metastatic, castration-resistant prostate cancer (mCRPC) who previously received abiraterone acetate, a novel androgen synthesis inhibitor (ASI). Cancer and Leukemia Group B (CALGB) trial 90401 (Alliance), a phase 3 trial in patients with mCRPC who received docetaxel-based chemotherapy, offered the opportunity to evaluate effect of prior ketoconazole, an earlier generation ASI, on clinical outcomes after docetaxel. METHODS: In CALGB trial 90401, 1050 men with chemotherapy-naive mCRPC were randomized to receive treatment with docetaxel and prednisone that included either bevacizumab or placebo. In total, 1005 men (96%) had data available regarding prior ketoconazole therapy. The observed effects of prior ketoconazole on overall survival (OS), progression-free survival (PFS), prostate-specific antigen (PSA) decline, and the objective response rate (ORR) were assessed using proportional hazards and Poisson regression methods adjusted for validated prognostic factors and treatment arm. RESULTS: Baseline characteristics between patients who did (N=277) and did not (N=728) receive prior ketoconazole therapy were similar. There were no statistically significant differences between patients who did and those who did not receive prior ketoconazole therapy with respect to OS (median OS, 21.1 months vs 22.3 months, respectively; stratified log-rank P=.635), PFS (median PFS, 8.1 months vs 8.6 months, respectively; stratified log-rank P=.342), the proportion achieving a decline ≥ 50% in PSA (61% vs 66%, respectively; relative risk, 1.09; adjusted P=.129), or ORR (39% vs 43%, respectively; relative risk, 1.11; adjusted P=.366). CONCLUSIONS: As measured by OS, PFS, PSA, and the ORR, there was no evidence that prior treatment with ketoconazole had an impact on the clinical outcomes of patients with mCRPC who received subsequent docetaxel-based therapy. The current results highlight the need for prospective studies to assess for potential cross-resistance with novel ASIs and to define the optimal sequence of therapy in mCRPC.


Assuntos
Antagonistas de Androgênios/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Antifúngicos/farmacologia , Bevacizumab , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/secundário , Quimioterapia Adjuvante , Progressão da Doença , Docetaxel , Quimioterapia Combinada , Seguimentos , Humanos , Agências Internacionais , Cetoconazol/farmacologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Orquiectomia , Prednisona/farmacologia , Prognóstico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Taxa de Sobrevida , Taxoides/administração & dosagem
19.
J Natl Compr Canc Netw ; 11(5 Suppl): 636-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23704232

RESUMO

Complex challenges face all players in the oncology landscape, from health care policy leaders and third-party payers, to practicing physicians and nurses, to patients and their families. In these unsteady economic times, possible answers proposed by some may represent part of the problem to others. A distinguished panel assembled at the NCCN 18th Annual Conference: Advancing the Standard of Cancer Care to explore the changing oncology landscape. This article is the synopsis of that discussion, with panelists shedding light on such issues as the astronomic cost of medical care, the need for clinicians to think outside the formulary, and the therapeutic decision-making process in the new world of "big data."


Assuntos
Oncologia/economia , Oncologia/normas , Comportamento Cooperativo , Atenção à Saúde/economia , Atenção à Saúde/normas , Humanos , Medicina de Precisão
20.
Chaos ; 23(4): 043106, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24387545

RESUMO

We consider the propagation of fronts in a periodically driven flowing medium. It is shown that the progress of fronts in these systems may be mediated by a turnstile mechanism akin to that found in chaotic advection. We first define the modified ("active") turnstile lobes according to the evolution of point sources across a transport boundary. We then show that the lobe boundaries may be constructed from stable and unstable burning invariant manifolds (BIMs)--one-way barriers to front propagation analogous to traditional invariant manifolds for passive advection. Because the BIMs are one-dimensional curves in a three-dimensional (xyθ) phase space, their projection into xy-space exhibits several key differences from their advective counterparts: (lobe) areas are not preserved, BIMs may self-intersect, and an intersection between stable and unstable BIMs does not map to another such intersection. These differences must be accommodated in the correct construction of the new turnstile. As an application, we consider a lobe-based treatment protocol for protecting an ocean bay from an invading algae bloom.


Assuntos
Modelos Teóricos , Reologia/métodos
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