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1.
Pediatr Res ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867029

RESUMO

BACKGROUND: Sleep problems are reported for up to 80% of autistic individuals. We examined whether parsimonious sets of items derived from the Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R) and the Brief Infant Sleep Questionnaire (BISQ) are superior to the standard M-CHAT-R in predicting subsequent autism spectrum disorder (ASD) diagnoses. METHODS: Participants from 11 Environmental influences on Child Health Outcomes (ECHO) cohorts were included. We performed logistic LASSO regression models with 10-fold cross-validation to identify whether a combination of items derived from the M-CHAT-R and BISQ are superior to the standard M-CHAT-R in predicting ASD diagnoses. RESULTS: The final sample comprised 1552 children. The standard M-CHAT-R had a sensitivity of 44% (95% CI: 34, 55), specificity of 92% (95% CI: 91, 94), and AUROC of 0.726 (95% CI: 0.663, 0.790). A higher proportion of children with ASD had difficulty falling asleep or resisted bedtime during infancy/toddlerhood. However, LASSO models revealed parental reports of sleep problems did not improve the accuracy of the M-CHAT-R in predicting ASD diagnosis. CONCLUSION: While children with ASD had higher rates of sleep problems during infancy/toddlerhood, there was no improvement in ASD developmental screening through the incorporation of parent-report sleep metrics. IMPACT: Parental-reported sleep problems are common in autism spectrum disorder (ASD). We investigated whether the inclusion of parental-reports of infant/toddler sleep patterns enhanced the effectiveness of developmental screening for autism. We reported higher rates of difficulty falling asleep and resisting bedtime during infancy and toddlerhood among children later diagnosed with ASD; however, we did not find an improvement in ASD developmental screening through the incorporation of parent-report sleep metrics. In our sample, the standard M-CHAT-R had a sensitivity of 39% among children of mothers with government insurance compared with a sensitivity of 53% among children of mothers with employer-based insurance.

2.
Annu Rev Public Health ; 44: 1-20, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36542771

RESUMO

Several peer-reviewed papers and reviews have examined the relationship between exposure to air pollution and COVID-19 spread and severity. However, many of the existing reviews on this topic do not extensively present the statistical challenges associated with this field, do not provide comprehensive guidelines for future researchers, and review only the results of a relatively small number of papers. We reviewed 139 papers, 127 of which reported a statistically significant positive association between air pollution and adverse COVID-19 health outcomes. Here, we summarize the evidence, describe the statistical challenges, and make recommendations for future research. To summarize the 139 papers with data from geographical locations around the world, we also present anopen-source data visualization tool that summarizes these studies and allows the research community to contribute evidence as new research papers are published.


Assuntos
Poluição do Ar , COVID-19 , Humanos , COVID-19/epidemiologia , Visualização de Dados , Material Particulado/efeitos adversos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Avaliação de Resultados em Cuidados de Saúde
3.
Bioelectromagnetics ; 44(1-2): 5-16, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36786477

RESUMO

Previous research has shown that virus infectivity can be dramatically reduced by radio frequency exposure in the gigahertz (GHz) frequency range. Given the worldwide SARS-CoV-2 pandemic, which has caused over 1 million deaths and has had a profound global economic impact, there is a need for a noninvasive technology that can reduce the transmission of virus among humans. RF is a potential wide area-of-effect viral decontamination technology that could be used in hospital rooms where patients are expelling virus, in grocery and convenience stores where local populations mix, and in first responder settings where rapid medical response spans many potentially infected locations within hours. In this study, we used bovine coronavirus (BCoV) as a surrogate of SARS-CoV-2 and exposed it to high peak power microwave (HPPM) pulses at four narrowband frequencies: 2.8, 5.6, 8.5, and 9.3 GHz. Exposures consisted of 2 µs pulses delivered at 500 Hz, with pulse counts varied by decades between 1 and 10,000. The peak field intensities (i.e. the instantaneous power density of each pulse) ranged between 0.6 and 6.5 MW/m2 , depending on the microwave frequency. The HPPM exposures were delivered to plastic coverslips containing BCoV dried on the surface. Hemagglutination (HA) and cytopathic effect analyses were performed 6 days after inoculation of host cells to assess viral infectivity. No change in viral infectivity was seen with increasing dose (pulse number) across the tested frequencies. Under all conditions tested, exposure did not reduce infectivity more than 1.0 log10. For the conditions studied, high peak power pulsed RF exposures in the 2-10 GHz range appear ineffective as a virucidal approach for hard surface decontamination. © 2023 Bioelectromagnetics Society.


Assuntos
COVID-19 , Inativação de Vírus , Animais , Bovinos , Humanos , SARS-CoV-2 , Micro-Ondas
4.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36769172

RESUMO

Cancer ablation therapies aim to be efficient while minimizing damage to healthy tissues. Nanosecond pulsed electric field (nsPEF) is a promising ablation modality because of its selectivity against certain cell types and reduced neuromuscular effects. We compared cell killing efficiency by PEF (100 pulses, 200 ns-10 µs duration, 10 Hz) in a panel of human esophageal cells (normal and pre-malignant epithelial and smooth muscle). Normal epithelial cells were less sensitive than the pre-malignant ones to unipolar PEF (15-20% higher LD50, p < 0.05). Smooth muscle cells (SMC) oriented randomly in the electric field were more sensitive, with 30-40% lower LD50 (p < 0.01). Trains of ten, 300-ns pulses at 10 kV/cm caused twofold weaker electroporative uptake of YO-PRO-1 dye in normal epithelial cells than in either pre-malignant cells or in SMC oriented perpendicularly to the field. Aligning SMC with the field reduced the dye uptake fourfold, along with a twofold reduction in Ca2+ transients. A 300-ns pulse induced a twofold smaller transmembrane potential in cells aligned with the field, making them less vulnerable to electroporation. We infer that damage to SMC from nsPEF ablation of esophageal malignancies can be minimized by applying the electric field parallel to the predominant SMC orientation.


Assuntos
Carcinoma , Neoplasias Esofágicas , Humanos , Eletricidade , Potenciais da Membrana , Eletroporação , Músculo Liso , Neoplasias Esofágicas/terapia
5.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446096

RESUMO

Reversing the pulse polarity, i.e., changing the electric field direction by 180°, inhibits electroporation and electrostimulation by nanosecond electric pulses (nsEPs). This feature, known as "bipolar cancellation," enables selective remote targeting with nsEPs and reduces the neuromuscular side effects of ablation therapies. We analyzed the biophysical mechanisms and measured how cancellation weakens and is replaced by facilitation when nsEPs are applied from different directions at angles from 0 to 180°. Monolayers of endothelial cells were electroporated by a train of five pulses (600 ns) or five paired pulses (600 + 600 ns) applied at 1 Hz or 833 kHz. Reversing the electric field in the pairs (180° direction change) caused 2-fold (1 Hz) or 20-fold (833 kHz) weaker electroporation than the train of single nsEPs. Reducing the angle between pulse directions in the pairs weakened cancellation and replaced it with facilitation at angles <160° (1 Hz) and <130° (833 kHz). Facilitation plateaued at about three-fold stronger electroporation compared to single pulses at 90-100° angle for both nsEP frequencies. The profound dependence of the efficiency on the angle enables novel protocols for highly selective focal electroporation at one electrode in a three-electrode array while avoiding effects at the other electrodes. Nanosecond-resolution imaging of cell membrane potential was used to link the selectivity to charging kinetics by co- and counter-directional nsEPs.


Assuntos
Eletroporação , Células Endoteliais , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Eletroporação/métodos , Terapia com Eletroporação
6.
Behav Brain Sci ; 46: e375, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37961777

RESUMO

Barzykowski and Moulin argue that common memory processes form the basis of involuntary autobiographical memory and the déjà vu experience. We think that they underemphasize the potential dissociability between processes that enact retrieval and the processes that produce conscious experience. We propose that retrieval and conscious experience result from different processes in both involuntary autobiographical memory and déjà vu experiences.


Assuntos
Déjà Vu , Memória Episódica , Humanos , Déjà Vu/psicologia , Estado de Consciência
7.
Psychol Med ; 52(8): 1437-1447, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-32914742

RESUMO

BACKGROUND: Family coaggregation of attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), bipolar disorder (BD), major depressive disorder (MDD) and schizophrenia have been presented in previous studies. The shared genetic and environmental factors among psychiatric disorders remain elusive. METHODS: This nationwide population-based study examined familial coaggregation of major psychiatric disorders in first-degree relatives (FDRs) of individuals with ASD. Taiwan's National Health Insurance Research Database was used to identify 26 667 individuals with ASD and 67 998 FDRs of individuals with ASD. The cohort was matched in 1:4 ratio to 271 992 controls. The relative risks (RRs) and 95% confidence intervals (CI) of ADHD, ASD, BD, MDD and schizophrenia were assessed among FDRs of individuals with ASD and ASD with intellectual disability (ASD-ID). RESULTS: FDRs of individuals with ASD have higher RRs of major psychiatric disorders compared with controls: ASD 17.46 (CI 15.50-19.67), ADHD 3.94 (CI 3.72-4.17), schizophrenia 3.05 (CI 2.74-3.40), BD 2.22 (CI 1.98-2.48) and MDD 1.88 (CI 1.76-2.00). Higher RRs of schizophrenia (4.47, CI 3.95-5.06) and ASD (18.54, CI 16.18-21.23) were observed in FDRs of individuals with both ASD-ID, compared with ASD only. CONCLUSIONS: The risk for major psychiatric disorders was consistently elevated across all types of FDRs of individuals with ASD. FDRs of individuals with ASD-ID are at further higher risk for ASD and schizophrenia. Our results provide leads for future investigation of shared etiologic pathways of ASD, ID and major psychiatric disorders and highlight the importance of mental health care delivered to at-risk families for early diagnoses and interventions.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Bipolar , Transtorno Depressivo Maior , Esquizofrenia , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/genética , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/genética , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Humanos , Esquizofrenia/epidemiologia , Esquizofrenia/genética
8.
J Environ Manage ; 301: 113789, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592661

RESUMO

Wildfire extent and their impacts are increasing around the world. Fire management agencies use fire behaviour simulation models operationally (during a wildfire event) or strategically for risk assessment and treatment. These models provide agencies with increased knowledge of fire potential to improve identification of the best strategies for reducing risk. One of the greatest areas of uncertainty in fire simulations is the data relating to fuel, which are usually based on simplified response trajectories with time since fire within vegetation communities. There is a clear need to better predict relevant fuel variables across landscapes to reduce uncertainties in fire simulations. In this study, we compare the performance of fuel hazard models based on environmental variables (environmental model) with those currently implemented based on a negative exponential relationship with time since fire (NEGEXP) using the state of Victoria in south-eastern Australia as an environmentally diverse case study. The models predicted similar broadscale patterns in fuel hazard but with considerable regional variation. The NEGEXP model was less accurate than the environmental model, which had 41-47% accuracy on an independent data set cf. 24-35% for NEGEXP. Model differences resulted in significant differences in the extent and spatial location of predicted fires with NEGEXP consistently predicting larger fires. Fuel is made up of the live and dead components of vegetation, both of which are influenced by a range of environmental factors. As our study highlights, ignoring environmental factors in simple fuel models based on broad vegetation types (like NEGEXP) will likely compromise the predictive accuracy of fire behaviour models. Only when environmental factors are accounted for can we more accurately predict fuels across landscapes and thereby improve the accuracy of fire behaviour predictions and the estimation of fire risks.


Assuntos
Incêndios , Incêndios Florestais , Modelos Teóricos , Vitória
9.
Proc Biol Sci ; 288(1957): 20211195, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34428964

RESUMO

The prevalence of disease-driven mass mortality events is increasing, but our understanding of spatial variation in their magnitude, timing and triggers are often poorly resolved. Here, we use a novel range-wide dataset comprised 48 810 surveys to quantify how sea star wasting disease affected Pycnopodia helianthoides, the sunflower sea star, across its range from Baja California, Mexico to the Aleutian Islands, USA. We found that the outbreak occurred more rapidly, killed a greater percentage of the population and left fewer survivors in the southern half of the species's range. Pycnopodia now appears to be functionally extinct (greater than 99.2% declines) from Baja California, Mexico to Cape Flattery, Washington, USA and exhibited severe declines (greater than 87.8%) from the Salish Sea to the Gulf of Alaska. The importance of temperature in predicting Pycnopodia distribution rose more than fourfold after the outbreak, suggesting latitudinal variation in outbreak severity may stem from an interaction between disease severity and warmer waters. We found no evidence of population recovery in the years since the outbreak. Natural recovery in the southern half of the range is unlikely over the short term. Thus, assisted recovery will probably be required to restore the functional role of this predator on ecologically relevant time scales.


Assuntos
Estrelas-do-Mar , Síndrome de Emaciação , Alaska , Animais , México/epidemiologia , Temperatura
10.
J Membr Biol ; 254(2): 141-156, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33427940

RESUMO

Nanosecond pulsed electric fields (nsPEFs) induce changes in the plasma membrane (PM), including PM permeabilization (termed nanoporation), allowing free passage of ions into the cell and, in certain cases, cell death. Recent studies from our laboratory show that the composition of the PM is a critical determinant of PM nanoporation. Thus, we hypothesized that the biological response to nsPEF exposure could be influenced by lipid microdomains, including caveolae, which are specialized invaginations of the PM that are enriched in cholesterol and contain aggregates of important cell signaling proteins, such as caveolin-1 (Cav1). Caveolae play a significant role in cellular signal transduction, including control of calcium influx and cell death by interaction of Cav1 with regulatory signaling proteins. Present results show that depletion of Cav1 increased the influx of calcium, while Cav1 overexpression produced the opposite effect. Additionally, Cav1 is known to bind and sequester important cell signaling proteins within caveolae, rendering the binding partners inactive. Imaging of the PM after nsPEF exposure showed localized depletion of PM Cav1 and results of co-immunoprecipitation studies showed dissociation of two critical Cav1 binding partners (transient receptor potential cation channel subfamily C1 (TRPC1) and inositol trisphosphate receptor (IP3R)) after exposure to nsPEFs. Release of TRPC1 and IP3R from Cav1 would activate downstream signaling cascades, including store-operated calcium entry, which could explain the influx in calcium after nsPEF exposure. Results of the current study establish a significant relationship between Cav1 and the activation of cell signaling pathways in response to nsPEFs.


Assuntos
Sinalização do Cálcio , Caveolina 1 , Membrana Celular/fisiologia , Eletricidade , Cálcio , Cavéolas , Caveolina 1/genética , Canais de Cátion TRPC
11.
Appl Opt ; 60(25): G10-G18, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613190

RESUMO

Understanding biological responses to directed energy (DE) is critical to ensure the safety of personnel within the Department of Defense. At the Air Force Research Laboratory, we have developed or adapted advanced optical imaging systems that quantify biophysical responses to DE. One notable cellular response to DE exposure is the formation of blebs, or semi-spherical protrusions of the plasma membrane in living cells. In this work, we demonstrate the capacity of quantitative phase imaging (QPI) to both visualize and quantify the formation of membrane blebs following DE exposure. QPI is an interferometric imaging tool that uses optical path length as a label-free contrast mechanism and is sensitive to the non-aqueous mass density, or dry mass, of living cells. Blebs from both CHO-K1 and U937 cells were generated after exposure to a series of 600 ns, 21.2 kV/cm electric pulses. These blebs were visualized in real time, and their dry mass relative to the rest of the cell body was quantified as a function of time. It is our hope that this system will lead to an improved understanding of both DE-induced and apoptotic blebbing.


Assuntos
Fenômenos Biofísicos/fisiologia , Membrana Celular , Extensões da Superfície Celular , Microscopia de Interferência/métodos , Imagem Óptica/métodos , Animais , Células CHO , Extensões da Superfície Celular/fisiologia , Extensões da Superfície Celular/ultraestrutura , Cricetulus , Estimulação Elétrica/métodos , Desenho de Equipamento , Humanos , Microscopia de Interferência/instrumentação , Imagem Óptica/instrumentação , Tamanho das Organelas , Células U937
12.
BMC Psychiatry ; 20(1): 121, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164636

RESUMO

BACKGROUND: This paper is a systematic review and meta-analysis of the efficacy of available medications for the treatment of restricted/repetitive behavior (RRBs) in Autism Spectrum Disorder (ASD). METHOD: We searched MEDLINE, Embase, PsycINFO, The Cochrane Library (Cochrane Database of Systematic Reviews (CDRS), the Cochrane Central Register of Controlled Trials (CENTRAL), database of Abstracts of Reviews of Effects (DARE)), Scopus, Epistimonikos, Clinicaltrials.gov, and included all randomized controlled trials published after 1993 that were directed at RRBs in patients with ASD of all ages. We extracted the relevant data from the published studies with a predefined data extraction form and assessed the risk of bias. The primary outcomes were change in restricted/repetitive behavior. We performed a meta-analysis using the random effect model and included studies with given mean and standard deviation. This study is registered with PROSPERO number CRD42018092660). RESULTS: We identified 14 randomized controlled trials that met initial inclusion criteria. After closer inspection, nine trials - involving 552 patients in total - were included in the final analysis. The meta-analysis found no significant difference between medications (including fluvoxamine, risperidone, fluoxetine, citalopram, oxytocin, N-Acetylcysteine, buspirone) and placebo in the treatment of RRBs in ASD (P = 0.20). Similarly, the sub-group meta-analysis also showed no significant difference between Selective Serotonin Reuptake Inhibitor (SSRIs) and placebo in the treatment of RRBs in ASD (P = 0.68). There was no evidence of publication bias. CONCLUSION: This meta-analysis finds little support for the routine use of medications to treat restricted/repetitive behaviors in Autism Spectrum Disorder. Further research of large, balanced trials with precise assessment tools and long-term follow-up are needed. TRIAL REGISTRATION: The study protocol is registered in PROSPERO (Reference number: CRD42018092660).


Assuntos
Transtorno do Espectro Autista/tratamento farmacológico , Transtorno do Espectro Autista/psicologia , Comportamento/efeitos dos fármacos , Humanos , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
13.
BMC Med Inform Decis Mak ; 20(1): 232, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943029

RESUMO

BACKGROUND: Nearly half of all mental health disorders develop prior to the age of 15. Early assessments, diagnosis, and treatment are critical to shortening single episodes of care, reducing possible comorbidity and long-term disability. In Norway, approximately 20% of all children and adolescents are experiencing mental health problems. To address this, health officials in Norway have called for the integration of innovative approaches. A clinical decision support system (CDSS) is an innovative, computer-based program that provides health professionals with clinical decision support as they care for patients. CDSS use standardized clinical guidelines and big data to provide guidance and recommendations to clinicians in real-time. IDDEAS (Individualised Digital DEcision Assist System) is a CDSS for diagnosis and treatment of child and adolescent mental health disorders. The aim of IDDEAS is to enhance quality, competency, and efficiency in child and adolescent mental health services (CAMHS). METHODS/DESIGN: IDDEAS is a mixed-methods innovation and research project, which consists of four stages: 1) Assessment of Needs and Preparation of IDDEAS; 2) The Development of IDDEAS CDSS Model; 3) The Evaluation of the IDDEAS CDSS; and, 4) Implementation & Dissemination. Both qualitative and quantitative methods will be used for the evaluation of IDDEAS CDSS model. Child and adolescent psychologists and psychiatrists (n = 30) will evaluate the IDDEAS` usability, acceptability and relevance for diagnosis and treatment of attention-deficit/hyperactivity disorder. DISCUSSION: The IDDEAS CDSS model is the first guidelines and data-driven CDSS to improve efficiency of diagnosis and treatment of child and adolescent mental health disorders in Norway. Ultimately, IDDEAS will help to improve patient health outcomes and prevent long-term adverse outcomes by providing each patient with evidence-based, customized clinical care. TRIAL REGISTRATION: ISRCTN, ISRCTN12094788. Ongoing study, registered prospectively 8 April 2020 https://doi.org/10.1186/ISRCTN12094788.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Sistemas de Apoio a Decisões Clínicas , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Criança , Comorbidade , Testes Diagnósticos de Rotina , Humanos , Noruega
14.
Biophys J ; 116(1): 120-126, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30579565

RESUMO

Direct observation of rapid membrane potential changes is critical to understand how complex neurological systems function. This knowledge is especially important when stimulation is achieved through an external stimulus meant to mimic a naturally occurring process. To enable exploration of this dynamic space, we developed an all-optical method for observing rapid changes in membrane potential at temporal resolutions of ∼25 ns. By applying a single 600-ns electric pulse, we observed sub-microsecond, continuous membrane charging and discharging dynamics. Close agreement between the acquired results and an analytical membrane-charging model validates the utility of this technique. This tool will deepen our understanding of the role of membrane potential dynamics in the regulation of many biological and chemical processes within living systems.


Assuntos
Membrana Celular/ultraestrutura , Potenciais da Membrana , Animais , Células CHO , Membrana Celular/química , Membrana Celular/fisiologia , Cricetinae , Cricetulus , Imagem Óptica/métodos
15.
Mem Cognit ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837105
16.
Bioelectromagnetics ; 39(6): 491-499, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29984845

RESUMO

Cell-circuit models have suggested that nanosecond pulsed electric fields (nsPEFs) can disrupt intracellular membranes including endoplasmic reticulum (ER), mitochondria, and/or nucleus thereby inducing intrinsic apoptotic pathways. Therefore, we hypothesized that the unfolded protein response (UPR) would be activated, due to the fluctuations of ionic concentrations, upon poration of the ER membrane. Quantitative real-time polymerase chain reaction was utilized to measure changes in messenger RNA (mRNA) expression of specific ER stress genes in adult human dermal fibroblast (HDFa) cells treated with tunicamycin (TM) (known ER stress inducer) and cells exposed to nsPEFs (100, 10-ns pulses at 150 kV/cm delivered at a repetition rate of 1 Hz). For HDFa cells, results showed time-dependent UPR activation to TM; however, when HDFa cells were exposed to nsPEFs, no significant changes in mRNA expression of ER stress genes, and/or caspase gene were observed. These results indicate that although cell death can be observed under these exposure parameters, it is most likely not initiated through activation of the UPR. Bioelectromagnetics. 2018;39:491-499, 2018. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.


Assuntos
Campos Eletromagnéticos , Fibroblastos/metabolismo , Resposta a Proteínas não Dobradas , Linhagem Celular , Campos Eletromagnéticos/efeitos adversos , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Íons/metabolismo , Análise em Microsséries , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Pele/citologia , Pele/metabolismo , Fatores de Tempo
17.
Memory ; 26(6): 807-815, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29243535

RESUMO

Processing fluency influences many types of judgments. Some metacognitive research suggests that the influence of processing fluency may be mediated by participants' beliefs. The current study explores the influence of processing fluency and beliefs on ease-of-learning (EOL) judgments. In two experiments (Exp 1: n = 94; Exp 2: n = 146), participants made EOL judgments on 24 six-letter concrete nouns, presented in either a constant condition (high fluency) with upper-case letters (e.g., BUCKET) or an alternating condition (low fluency) with mixed upper- and lower-case letters (e.g., bUcKeT). After judging words individually, participants studied the words and completed a free recall test. Finally, participants indicated what condition they believed made the words more likely to be learned. Results show constant-condition words were judged as more likely to be learned than alternating condition words, but the difference varied with beliefs. Specifically, the difference was biggest when participants believed the constant condition made words more likely to be learned, followed by believing there was no difference, and then believing the alternating condition made words more likely to be learned. Thus, we showed that processing fluency has a direct effect on EOL judgments, but the effect is moderated by beliefs.


Assuntos
Julgamento , Aprendizagem , Rememoração Mental , Adulto , Feminino , Humanos , Masculino , Metacognição , Adulto Jovem
18.
Biochim Biophys Acta ; 1858(11): 2636-2646, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27431479

RESUMO

Previous work from our laboratory demonstrated nanopore formation in cell membranes following exposure to nanosecond pulsed electric fields (nsPEF). We observed differences in sensitivity to nsPEF in both acute membrane injury and 24h lethality across multiple cells lines. Based on these data, we hypothesize that the biological response of cells to nsPEF is dependent on the physical properties of the plasma membrane (PM), including regional cholesterol content. Results presented in this paper show that depletion of membrane cholesterol disrupts the PM and increases the permeability of cells to small molecules, including propidium iodide and calcium occurring after fewer nsPEF. Additionally, cholesterol depletion concurrently decreases the "dose" of nsPEF required to induce lethality. In summary, the results of the current study suggest that the PM cholesterol composition is an important determinant in the cellular response to nsPEF.


Assuntos
Membrana Celular/química , Colesterol/metabolismo , Eletroporação , Animais , Células CHO , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Cricetulus , Eletricidade , Humanos , Células Jurkat , Imagem Molecular , Propídio/metabolismo , beta-Ciclodextrinas/farmacologia
19.
Biochim Biophys Acta ; 1858(11): 2795-2803, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27535877

RESUMO

Plasma membrane disruption can trigger a host of cellular activities. One commonly observed type of disruption is pore formation. Molecular dynamic (MD) simulations of simplified lipid membrane structures predict that controllably disrupting the membrane via nano-scale poration may be possible with nanosecond pulsed electric fields (nsPEF). Until recently, researchers hoping to verify this hypothesis experimentally have been limited to measuring the relatively slow process of fluorescent markers diffusing across the membrane, which is indirect evidence of nanoporation that could be channel-mediated. Leveraging recent advances in nonlinear optical microscopy, we elucidate the role of pulse parameters in nsPEF-induced membrane permeabilization in live cells. Unlike previous techniques, it is able to directly observe loss of membrane order at the onset of the pulse. We also develop a complementary theoretical model that relates increasing membrane permeabilization to membrane pore density. Due to the significantly improved spatial and temporal resolution possible with our imaging method, we are able to directly compare our experimental and theoretical results. Their agreement provides substantial evidence that nanoporation does occur and that its development is dictated by the electric field distribution.


Assuntos
Membrana Celular/química , Eletroporação/métodos , Sondas Moleculares/metabolismo , Compostos de Piridínio/metabolismo , Permeabilidade da Membrana Celular , Eletricidade , Campos Eletromagnéticos , Humanos , Células Jurkat , Microscopia de Fluorescência por Excitação Multifotônica , Modelos Biológicos , Análise de Célula Única
20.
Biochim Biophys Acta Biomembr ; 1859(3): 438-445, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28064021

RESUMO

Previously, it was demonstrated that nanometer-sized pores (nanopores) are formed in outer cellular membranes after exposure to nanosecond electric pulses (nsEPs). We reported that plasma membrane nanoporation affects phospholipids of the cell membrane, culminating in cascading phosphoinositide phosphatidylinositol-4,5-bisphosphate (PIP2) intracellular signaling. In the current study, we show that nsEPs initiated electric field (EF) dose-dependent PIP2 hydrolysis and/or depletion from the plasma membrane. This process was confirmed using fluorescent optical probes of PIP2 hydrolysis: PLCδ-PH-EGFP and GFP-C1-PKCγ-C1a. The 50% maximum response occurs with a single 600ns pulse achieving an effective dose (ED50) of EF~8kV/cm within our model cell system. At 16.2kV/cm, the ED50 for the pulse width was 484ns. Reduction of the pulse width or EF amplitude gradually reduced the observed effect, but twenty 60ns 16.2kV/cm pulses produced an effect similar to a single 600ns pulse of the same amplitude. Propidium iodide (PI) uptake after the nsEP exposure confirmed a strong relationship between EF-induced plasma membrane impact and PIP2 depletion. These results have expanded our current knowledge of nsEPs dependent cell physiological effects, and serve as a basis for model development of new exposure standards, providing novel tools for drug independent stimulation and approaches to differential modulation of key cellular functions.


Assuntos
Eletricidade , Fosfatidilinositol 4,5-Difosfato/metabolismo , Animais , Células CHO , Cálcio/metabolismo , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Citoplasma/metabolismo , Hidrólise , Inositol 1,4,5-Trifosfato/metabolismo , Fosfolipase C delta/genética , Fosfolipase C delta/metabolismo , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , Transdução de Sinais , Fatores de Tempo
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