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1.
Med Educ ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850193

RESUMO

PURPOSE: Variable assessments of learner performances can occur when different assessors determine different elements to be differently important or salient. How assessors determine the importance of performance elements has historically been thought to occur idiosyncratically and thus be amenable to assessor training interventions. More recently, a main source of variation found among assessors was two underlying factors that were differently emphasised: medical expertise and interpersonal skills. This gave legitimacy to the theory that different interpretations of the same performance may represent multiple truths. A faculty development activity introducing assessors to entrustable professional activities in which they estimated a learner's level of readiness for entrustment provided an opportunity to qualitatively explore assessor variation in the context of an interaction and in a setting in which interpersonal skills are highly valued. METHODS: Using a constructivist grounded theory approach, we explored variation in assessment processes among a group of palliative medicine assessors who completed a simulated direct observation and assessment of the same learner interaction. RESULTS: Despite identifying similar learner strengths and areas for improvement, the estimated level of readiness for entrustment varied substantially among assessors. Those who estimated the learner as not yet ready for entrustment seemed to prioritise what information was exchanged and viewed missed information as performance gaps. Those who estimated the learner as ready for entrustment seemed to prioritise how information was exchanged and viewed the same missed information as personal style differences or appropriate clinical judgement. When presented with a summary, assessors expressed surprise and concern about the variation. CONCLUSION: A main source of variation among our assessors was the differential salience of performance elements that align with medical expertise and interpersonal skills. These data support the theory that when assessing an interaction, differential salience for these two factors may be an important and perhaps inevitable source of assessor variation.

2.
Dev Neurosci ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38190820

RESUMO

INTRODUCTION: A striking pattern in young children after severe TBI is when the entire cortical ribbon displays tissue damage: hemispheric hypodensity (HH). HH is often a result of abusive head trauma (AHT). We previously reported a model of HH in a gyrencephalic species where a combination of injuries consisting of 1) cortical impact, 2) midline shift, 3) subdural hematoma/subarachnoid hemorrhage, 4) traumatic seizures, and 5) brief apnea and hypoventilation, resulted in extensive, hypoxic-ischemic type injury. Importantly, this mechanism closely resembles that seen in children, with relative sparing of the contralateral cortex, thus, ruling out a pure asphyxia mechanism. In this model, piglets of similar developmental stage to human toddlers (postnatal day 30, PND30) have extensive hypoxic-ischemic damage to the cortical ribbon with sparing of the contralateral hemisphere and deep gray matter areas. However, piglets of similar developmental stage to human infants (postnatal day 7, PND7) have less hypoxic-ischemic damage that is notably bilateral and patchy. We therefore sought to discover whether the extensive tissue damage observed in PND30 was due to a greater upregulation of matrix metalloproteinases (MMPs). MATERIALS AND METHODS: In PND 7 or PND 30 piglets receiving AHT injuries (cortical impact, midline shift, subdural hematoma/subarachnoid hemorrhage, traumatic seizures, and brief apnea and hypoventilation) or a sham injury, the pattern of albumin extravasation and MMP-9 upregulation throughout the brain was determined via immunohistochemistry, brain tissue adjacent to the cortical impact where the tissue damage spreads was collected for Western blots, and the gelatinase activity was determined over time in peripheral plasma. EEG was recorded and piglets survived up to 24 hours after injury administration. RESULTS: The pattern of albumin extravasation, indicating vasogenic edema, as well as increase in MMP-9, were both present at the same areas of hypoxic-ischemic tissue damage. Evidence from immunohistochemistry, western blot, and zymogens demonstrate that MMP- 2,- 3 or -9 are constitutively expressed during immaturity and are not different between developmental stages; however, active forms are upregulated in PND30 but not PND7 after in response to AHT model injuries. Furthermore, peripheral active MMP-9 was downregulated after model injuries in PND7. CONCLUSIONS: This differential response to AHT model injuries might confer protection to the PND7 brain. Additionally, we find that immature gyrencephalic species have a greater baseline and array of MMP's than previously demonstrated in rodent species. Treatment with an oral or intravenous broad-spectrum matrix metalloproteinase inhibitor might reduce the extensive spread of injury in PND30, but the exposure to metalloproteinase inhibitors must be acute as to not interfere with the homeostatic role of matrix metalloproteinases in normal postnatal brain development and plasticity as well as post-injury synaptogenesis and tissue repair.

3.
Nano Lett ; 23(7): 2771-2777, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36921321

RESUMO

Two-dimensional transition metal dichalcogenides (2D TMDCs) are promising candidates for ultrathin active nanophotonic elements due to the strong tunable excitonic resonances that dominate their optical response. Here, we demonstrate dynamic beam steering by an active van der Waals metasurface that leverages large complex refractive index tunability near excitonic resonances in monolayer molybdenum diselenide (MoSe2). Through varying the radiative and nonradiative rates of the excitons, we can dynamically control both the reflection amplitude and phase profiles, resulting in an excitonic phased array metasurface. Our experiments show reflected light steering to angles between -30° and 30° at different resonant wavelengths corresponding to the A exciton and B exciton. This active van der Waals metasurface relies solely on the excitonic resonances of the monolayer MoSe2 material rather than geometric resonances of patterned nanostructures, suggesting the potential to harness the tunability of excitonic resonances for wavefront shaping in emerging photonic applications.

4.
ANZ J Surg ; 93(1-2): 294-301, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36566493

RESUMO

BACKGROUND: Breast reconstruction following oncological resection is becoming more common in recent years. In some ladies, implant reconstruction is not ideal due to significant implant visibility or palpability. Autologous reconstruction addresses the limitations of implant reconstruction but results in potential donor site morbidities. To date, there is no clear advantage ascribed to any technique. With appropriate selection, patients with adequate lateral mammary fold have the option of reconstruction with MCW-LICAP flap. We present our techniques and outcomes from a series of 29 patients who underwent MCW-LICAP flap. METHODS: A retrospective review of consecutive patients who underwent curative resection for breast cancer with immediate MCW-LICAP flap reconstruction, between July 2018 to April 2022 was conducted. The techniques used with its variations along with video demonstrations are presented. RESULTS: A total of 29 patients underwent 34 procedures. Nineteen breast conserving surgeries and 15 mastectomies were completed, and immediate reconstruction performed in all cases. Twenty-three patients had MCW-LICAP, 1 with a Stacked intercostal artery perforator (STICAP) flap, and 5 had MCW-LICAP combined with a Goldilocks mastectomy. There were no cases of complications requiring re-operation. All patients had acceptable time to adjuvant therapy with a median of 36 days. Learning curve analysis showed a significant reduction in operative time after the 6th case. CONCLUSION: In our preliminary experience, MCW-LICAP flap is a safe, reliable, and versatile oncoplastic reconstruction option.


Assuntos
Neoplasias da Mama , Mamoplastia , Retalho Perfurante , Parede Torácica , Humanos , Feminino , Mastectomia , Neoplasias da Mama/cirurgia , Parede Torácica/cirurgia , Resultado do Tratamento , Retalho Perfurante/irrigação sanguínea , Mamoplastia/métodos , Estudos Retrospectivos , Artérias/cirurgia
5.
Ann Glob Health ; 88(1): 23, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433285

RESUMO

Background: Beginning in 2020, the COVID pandemic disrupted many planned annual meetings that relied on travel to a destination for sharing scholarship, networking, and planning future collaborations. As with many organizations, the Consortium of Universities for Global Health (CUGH) began exploring the utilization of a virtual platform on which to conduct the annual conference. Objective: We sought to understand the value of conducting an annual conference virtually and to evaluate the added benefit of utilizing a learning management system. Methods: Routinely collected registration data was used for the CUGH 2021 annual conference, which was completely virtual, and compared to in-person registration data from prior years. In addition, tracking and engagement data from a learning management system was reviewed to understand participation. Findings: The virtual conference attracted the greatest number of registrations, from the largest number of countries since the organization began in 2008. Analyzing the engagement of participants with specific sessions through the on-line learning management system allowed a deeper understanding of the popularity and value of topics. Conclusion: A virtual format is an efficient and effective venue for scholarly conferences. The additional information gained from an on-line learning management system can provide valuable information for future conference planning.


Assuntos
COVID-19 , Saúde Global , COVID-19/epidemiologia , Congressos como Assunto , Humanos , Pandemias , SARS-CoV-2 , Universidades
6.
Fam Syst Health ; 40(2): 182-209, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34928653

RESUMO

INTRODUCTION: Integrating behavioral health (BH) and primary care is an important strategy to improve health behaviors, mental health, and substance misuse, particularly at community health centers (CHCs) where disease burden is high and access to mental health services is low. Components of different integrated BH models are often combined in practice. It is unknown which components distinguish developing versus established integrated BH programs. METHOD: A survey was mailed to 128 CHCs in 10 Midwestern states in 2016. Generalized estimating equation models were used to assess associations between program characteristics and stage of integration implementation (precontemplation, contemplation, preparation, action, or maintenance). Content analysis of open-ended responses identified integration barriers. RESULTS: Response rate was 60% (N = 77). Most CHCs had colocated BH and primary care services, warm hand-offs from primary care to BH clinicians, shared scheduling and electronic health record (EHR) systems, and depression and substance use disorder screening. Thirty-two CHCs (42%) indicated they had completed integration and were focused on quality improvement (maintenance). Being in the maintenance stage was associated with having a psychologist on staff (odds ratio [OR] = 7.16, 95% confidence interval [CI] [2.76, 18.55]), a system for tracking referrals (OR = 3.42, 95% CI [1.03, 11.36]), a registry (OR = 2.71, 95% CI [1.86, 3.94]), PCMH designation (OR = 2.82, 95% CI [1.48, 5.37]), and a lower proportion of Black/African American patients (OR = .82, 95% CI [.75, .89]). The most common barriers to integration were difficulty recruiting and retaining BH clinicians and inadequate reimbursement. DISCUSSION: CHCs have implemented many foundational components of integrated BH. Future work should address barriers to integration and racial disparities in access to integrated BH. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Prestação Integrada de Cuidados de Saúde , Serviços de Saúde Mental , Psiquiatria , Humanos , Atenção Primária à Saúde/métodos , Saúde Pública
7.
Nano Lett ; 21(18): 7602-7608, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34468150

RESUMO

Two-dimensional transition metal dichalcogenides are promising candidates for ultrathin light modulators due to their highly tunable excitonic resonances at visible and near-infrared wavelengths. At cryogenic temperatures, large excitonic reflectivity in monolayer molybdenum diselenide (MoSe2) has been shown, but the permittivity and index modulation have not been studied. Here, we demonstrate large gate-tunability of complex refractive index in monolayer MoSe2 by Fermi level modulation and study the doping dependence of the A and B excitonic resonances for temperatures between 4 and 150 K. By tuning the charge density, we observe both temperature- and carrier-dependent epsilon-near-zero response in the permittivity and transition from metallic to dielectric near the A exciton energy. We attribute the dynamic control of the refractive index to the interplay between radiative and non-radiative decay channels that are tuned upon gating. Our results suggest the potential of monolayer MoSe2 as an active material for emerging photonics applications.


Assuntos
Molibdênio , Elementos de Transição , Óptica e Fotônica , Refratometria , Temperatura
8.
Aging Cell ; 20(7): e13419, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34216536

RESUMO

Sirtuin1 (SIRT1) and Sirtuin3 (SIRT3) protects cardiac function against ischemia/reperfusion (I/R) injury. Mitochondria are critical in response to myocardial I/R injury as disturbance of mitochondrial dynamics contributes to cardiac dysfunction. It is hypothesized that SIRT1 and SIRT3 are critical components to maintaining mitochondria homeostasis especially mitochondrial dynamics to exert cardioprotective actions under I/R stress. The results demonstrated that deficiency of SIRT1 and SIRT3 in aged (24-26 months) mice hearts led to the exacerbated cardiac dysfunction in terms of cardiac systolic dysfunction, cardiomyocytes contractile defection, and abnormal cardiomyocyte calcium flux during I/R stress. Moreover, the deletion of SIRT1 or SIRT3 in young (4-6 months) mice hearts impair cardiomyocyte contractility and shows aging-like cardiac dysfunction upon I/R stress, indicating the crucial role of SIRT1 and SIRT3 in protecting myocardial contractility from I/R injury. The biochemical and seahorse analysis showed that the deficiency of SIRT1/SIRT3 leads to the inactivation of AMPK and alterations in mitochondrial oxidative phosphorylation (OXPHOS) that causes impaired mitochondrial respiration in response to I/R stress. Furthermore, the remodeling of the mitochondria network goes together with hypoxic stress, and mitochondria undergo the processes of fusion with the increasing elongated branches during hypoxia. The transmission electron microscope data showed that cardiac SIRT1/SIRT3 deficiency in aging alters mitochondrial morphology characterized by the impairment of mitochondria fusion under I/R stress. Thus, the age-related deficiency of SIRT1/SIRT3 in the heart affects mitochondrial dynamics and respiration function that resulting in the impaired contractile function of cardiomyocytes in response to I/R.


Assuntos
Dinâmica Mitocondrial/genética , Miócitos Cardíacos/metabolismo , Sirtuína 1/deficiência , Sirtuína 3/deficiência , Envelhecimento , Animais , Humanos , Camundongos
9.
Glob Public Health ; 16(8-9): 1223-1236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33891518

RESUMO

The rate of infectious disease outbreaks has been accelerating over the past two decades, from the SARS epidemic in 2003 to COVID-19 in 2020. Termed by some as the twenty-first century's first pandemic, SARS originated in China and alerted the country to the importance of public health and epidemic response. After SARS, China improved its health infrastructure and reformed its political and legal health governance system. The emergence of COVID-19 from Wuhan in late 2019 put those reforms to the test. This paper analyses China's public health and epidemic response policies from a historical perspective, tracing the evolution of Chinese public health policies after the SARS outbreak in 2003. This paper assesses China's response to COVID-19 and how post-SARS policy reforms, particularly in epidemic response, played out on the ground in Wuhan. What policies worked well? What were the challenges faced? Based on the policy analysis, this paper presents recommendations for how China can improve its epidemic response through strengthened infectious disease surveillance, more transparent political coordination, and expanded public health infrastructure.


Assuntos
COVID-19 , Epidemias , Políticas , Saúde Pública , Síndrome Respiratória Aguda Grave , COVID-19/epidemiologia , COVID-19/prevenção & controle , China/epidemiologia , Epidemias/prevenção & controle , Humanos , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/prevenção & controle
10.
Transl Vis Sci Technol ; 9(9): 13, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32879769

RESUMO

Purpose: Lacritin is a tear glycoprotein with pro-tearing and pro-ocular surface homeostasis activities that is selectively deficient in most dry eye tears. Proteoforms include an active monomer, inactive polymers, and a splice variant termed lacritin-c. Quantitation of the different proteoforms of tear lacritin may provide a diagnostic tool for ocular diseases. Here, we report the development of an immunoassay for the quantification of multiple lacritin proteoforms in human tear samples. Methods: Basal tears collected on Schirmer test strips with anesthesia were eluted by diffusion and centrifugation under optimized conditions. Tear protein concentrations were determined, and 2.56 µg of each sample was separated by SDS-PAGE followed by western blot analysis. Blots were challenged with anti-Pep Lac N-term antibodies. Detection was with fluorescent secondary antibodies visualized by the LI-COR Odyssey CLx imaging system and quantified with standard curves of recombinant lacritin. Results: The percent total lacritin (ng lacritin/100 ng total protein) ranged from 1.8% to 14.8%. Monomer, lacritin-c, and polymer proteoform percent total protein ranged from 1.1% to 6.3%, 0.3% to 5.4%, and 0.7% to 5.7%, respectively. Monomer lacritin was detected at concentrations of 6 to 176 µM, with lacritin-c and polymer proteoforms at 2 to 46 µM and 1 to 23 µM, respectively. Conclusions: This assay greatly exceeds the power and sensitivity of our prior lacritin enzyme-linked immunosorbent assay that was not capable of distinguishing monomer from polymers and lacritin-c proteoforms. Translational Relevance: A new method has been developed to quantitate multiple proteoforms of tear lacritin in preparation for analyses of samples from clinical trials.


Assuntos
Síndromes do Olho Seco , Proteínas do Olho , Western Blotting , Proteínas do Olho/genética , Glicoproteínas , Humanos , Lágrimas
11.
PLoS Comput Biol ; 15(12): e1007510, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31790389

RESUMO

Quantifying cell-type proportions and their corresponding gene expression profiles in tissue samples would enhance understanding of the contributions of individual cell types to the physiological states of the tissue. Current approaches that address tissue heterogeneity have drawbacks. Experimental techniques, such as fluorescence-activated cell sorting, and single cell RNA sequencing are expensive. Computational approaches that use expression data from heterogeneous samples are promising, but most of the current methods estimate either cell-type proportions or cell-type-specific expression profiles by requiring the other as input. Although such partial deconvolution methods have been successfully applied to tumor samples, the additional input required may be unavailable. We introduce a novel complete deconvolution method, CDSeq, that uses only RNA-Seq data from bulk tissue samples to simultaneously estimate both cell-type proportions and cell-type-specific expression profiles. Using several synthetic and real experimental datasets with known cell-type composition and cell-type-specific expression profiles, we compared CDSeq's complete deconvolution performance with seven other established deconvolution methods. Complete deconvolution using CDSeq represents a substantial technical advance over partial deconvolution approaches and will be useful for studying cell mixtures in tissue samples. CDSeq is available at GitHub repository (MATLAB and Octave code): https://github.com/kkang7/CDSeq.


Assuntos
Perfilação da Expressão Gênica/estatística & dados numéricos , Análise de Sequência de RNA/estatística & dados numéricos , Aprendizado de Máquina não Supervisionado , Linhagem Celular , Biologia Computacional/métodos , Simulação por Computador , Bases de Dados de Ácidos Nucleicos/estatística & dados numéricos , Humanos , Leucócitos/classificação , Leucócitos/metabolismo , Reconhecimento Automatizado de Padrão , Transcriptoma
12.
PLoS One ; 14(6): e0218067, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31199813

RESUMO

Due to the poor prognosis of advanced metastatic melanoma, it is crucial to find early biomarkers that help identify which melanomas will metastasize. By comparing the gene expression data from primary and cutaneous melanoma samples from The Cancer Genome Atlas (TCGA), we identified GPC6 among a set of genes whose expression levels can distinguish between primary melanoma and regional cutaneous/subcutaneous metastases. Glypicans are thought to play a role in tumor growth by regulating the signaling pathways of Wnt, Hedgehogs, fibroblast growth factors (FGFs), and bone morphogenetic proteins (BMPs). We showed that GPC6 expression was up-regulated in a melanoma cell line compared to normal melanocytes and in metastatic melanoma compared to primary melanoma. Furthermore, GPC6 expression was positively correlated with genes largely involved in cell adhesion and migration in both melanoma samples and in RNA-seq samples from other TCGA tumors. Our results suggest that GPC6 may play a role in tumor metastatic progression. In TCGA melanoma samples, we also showed that GPC6 expression was negatively correlated with miR-509-3p, which has previously been shown to function as a tumor suppressor in various cancer cell lines. We overexpressed miR-509-3p in A375 melanoma cells and showed that GPC6 expression was significantly suppressed. This result suggested that GPC6 was a putative target of miR-509-3p in melanoma. Together, our findings identified GPC6 as an early biomarker for melanoma metastatic progression, one that can be regulated by miR-509-3p.


Assuntos
Biomarcadores Tumorais/biossíntese , Regulação Neoplásica da Expressão Gênica , Glipicanas/biossíntese , Melanoma/metabolismo , Proteínas de Neoplasias/biossíntese , Neoplasias Cutâneas/metabolismo , Regulação para Cima , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Feminino , Glipicanas/genética , Humanos , Masculino , Melanoma/genética , Melanoma/patologia , MicroRNAs/biossíntese , MicroRNAs/genética , Metástase Neoplásica , Proteínas de Neoplasias/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
13.
Pediatr Crit Care Med ; 19(2): 131-136, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29206730

RESUMO

OBJECTIVE: Fluid restriction is reported to be a barrier in providing adequate nutrition following cardiac surgery. The specific aim of this study was to evaluate the adequacy of nutritional intake during the postoperative period using anthropometrics by comparing preoperative weight status, as measured by weight-for-age z scores, to weight status at discharge home. DESIGN: Prospective cohort study. SETTING: Cardiac ICU at Miami Children's Hospital. PATIENTS: Infants from birth to 12 months old who were scheduled for cardiac surgery at Miami Children's Hospital between December 2013 and September 2014 were followed during the postoperative stay. INTERVENTIONS: Observational study. MEASUREMENTS AND MAIN RESULTS: Preoperative and discharge weight-for-age z scores were analyzed. The Risk Adjustment for Congenital Heart Surgery 1 categories were obtained to account for the individual complexity of each case. In patients who had preoperative and discharge weights available (n = 40), the mean preoperative weight-for-age z score was -1.3 ± 1.43 and the mean weight-for-age z score at hospital discharge was -1.89 ± 1.35 with a mean difference of 0.58 ± 0.5 (p < 0.001). A higher Risk Adjustment for Congenital Heart Surgery 1 category was correlated with a greater decrease in weight-for-age z scores (r = -0.597; p = 0.002). CONCLUSIONS: Nutritional status during the postoperative period was found inadequate through the use of objective anthropometric measures and by comparing them with normal growth curves. Increase in surgical risk categories predicted a greater decrease in weight-for-age z scores. The development of future protocols for nutritional intervention should consider surgical risk categories.


Assuntos
Peso Corporal , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Desenvolvimento Infantil , Hidratação/efeitos adversos , Estado Nutricional , Estudos de Coortes , Feminino , Florida , Hidratação/métodos , Cardiopatias Congênitas/cirurgia , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Tempo de Internação/estatística & dados numéricos , Masculino , Período Pós-Operatório , Estudos Prospectivos , Risco Ajustado , Fatores de Risco
14.
J Biol Chem ; 292(49): 20228-20239, 2017 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-29021253

RESUMO

Small nucleolar RNAs (snoRNAs) guide chemical modifications of ribosomal and small nuclear RNAs, functions that are carried out in the nucleus. Although most snoRNAs reside in the nucleolus, a growing body of evidence indicates that snoRNAs are also present in the cytoplasm and that snoRNAs move between the nucleus and cytoplasm by a mechanism that is regulated by lipotoxic and oxidative stress. Here, in a genome-wide shRNA-based screen, we identified nuclear export factor 3 (NXF3) as a transporter that alters the nucleocytoplasmic distribution of box C/D snoRNAs from the ribosomal protein L13a (Rpl13a) locus. Using RNA-sequencing analysis, we show that NXF3 associates not only with Rpl13a snoRNAs, but also with a broad range of box C/D and box H/ACA snoRNAs. Under homeostatic conditions, gain- or loss-of-function of NXF3, but not related family member NXF1, decreases or increases cytosolic Rpl13a snoRNAs, respectively. Furthermore, treatment with the adenylyl cyclase activator forskolin diminishes cytosolic localization of the Rpl13a snoRNAs through a mechanism that is dependent on NXF3 but not NXF1. Our results provide evidence of a new role for NXF3 in regulating the distribution of snoRNAs between the nuclear and cytoplasmic compartments.


Assuntos
Transporte Ativo do Núcleo Celular , Proteínas de Transporte Nucleocitoplasmático/fisiologia , RNA Nucleolar Pequeno/metabolismo , Proteínas de Ligação a RNA/fisiologia , Animais , Sequência de Bases , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Camundongos , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Proteínas Ribossômicas
15.
JMIR Mhealth Uhealth ; 4(2): e40, 2016 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-27122452

RESUMO

BACKGROUND: Wearable activity trackers are promising as interventions that offer guidance and support for increasing physical activity and health-focused tracking. Most adults do not meet their recommended daily activity guidelines, and wearable fitness trackers are increasingly cited as having great potential to improve the physical activity levels of adults. OBJECTIVE: The objective of this study was to use the Coventry, Aberdeen, and London-Refined (CALO-RE) taxonomy to examine if the design of wearable activity trackers incorporates behavior change techniques (BCTs). A secondary objective was to critically analyze whether the BCTs present relate to known drivers of behavior change, such as self-efficacy, with the intention of extending applicability to older adults in addition to the overall population. METHODS: Wearing each device for a period of 1 week, two independent raters used CALO-RE taxonomy to code the BCTs of the seven wearable activity trackers available in Canada as of March 2014. These included Fitbit Flex, Misfit Shine, Withings Pulse, Jawbone UP24, Spark Activity Tracker by SparkPeople, Nike+ FuelBand SE, and Polar Loop. We calculated interrater reliability using Cohen's kappa. RESULTS: The average number of BCTs identified was 16.3/40. Withings Pulse had the highest number of BCTs and Misfit Shine had the lowest. Most techniques centered around self-monitoring and self-regulation, all of which have been associated with improved physical activity in older adults. Techniques related to planning and providing instructions were scarce. CONCLUSIONS: Overall, wearable activity trackers contain several BCTs that have been shown to increase physical activity in older adults. Although more research and development must be done to fully understand the potential of wearables as health interventions, the current wearable trackers offer significant potential with regard to BCTs relevant to uptake by all populations, including older adults.

16.
JMIR Mhealth Uhealth ; 4(1): e7, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26818775

RESUMO

BACKGROUND: Physical inactivity and sedentary behavior increase the risk of chronic illness and death. The newest generation of "wearable" activity trackers offers potential as a multifaceted intervention to help people become more active. OBJECTIVE: To examine the usability and usefulness of wearable activity trackers for older adults living with chronic illness. METHODS: We recruited a purposive sample of 32 participants over the age of 50, who had been previously diagnosed with a chronic illness, including vascular disease, diabetes, arthritis, and osteoporosis. Participants were between 52 and 84 years of age (mean 64); among the study participants, 23 (72%) were women and the mean body mass index was 31 kg/m(2). Participants tested 5 trackers, including a simple pedometer (Sportline or Mio) followed by 4 wearable activity trackers (Fitbit Zip, Misfit Shine, Jawbone Up 24, and Withings Pulse) in random order. Selected devices represented the range of wearable products and features available on the Canadian market in 2014. Participants wore each device for at least 3 days and evaluated it using a questionnaire developed from the Technology Acceptance Model. We used focus groups to explore participant experiences and a thematic analysis approach to data collection and analysis. RESULTS: Our study resulted in 4 themes: (1) adoption within a comfort zone; (2) self-awareness and goal setting; (3) purposes of data tracking; and (4) future of wearable activity trackers as health care devices. Prior to enrolling, few participants were aware of wearable activity trackers. Most also had been asked by a physician to exercise more and cited this as a motivation for testing the devices. None of the participants planned to purchase the simple pedometer after the study, citing poor accuracy and data loss, whereas 73% (N=32) planned to purchase a wearable activity tracker. Preferences varied but 50% felt they would buy a Fitbit and 42% felt they would buy a Misfit, Jawbone, or Withings. The simple pedometer had a mean acceptance score of 56/95 compared with 63 for the Withings, 65 for the Misfit and Jawbone, and 68 for the Fitbit. To improve usability, older users may benefit from devices that have better compatibility with personal computers or less-expensive Android mobile phones and tablets, and have comprehensive paper-based user manuals and apps that interpret user data. CONCLUSIONS: For older adults living with chronic illness, wearable activity trackers are perceived as useful and acceptable. New users may need support to both set up the device and learn how to interpret their data.

17.
18.
Genes Dis ; 2(1): 96-105, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25815368

RESUMO

Sustained, high level transgene expression in mammalian cells, especially stem cells, may be desired in many cases for studying gene functions. Traditionally, stable transgene expression has been accomplished by using retroviral or lentiviral vectors. However, such viral vector-mediated transgene expression is often at low levels and can be reduced over time due to low copy numbers and/or chromatin remodeling repression. The piggyBac transposon has emerged as a promising non-viral vector system for efficient gene transfer into mammalian cells. Despite its inherent advantages over lentiviral and retroviral systems, piggyBac system has not been widely used, at least in part due to the limited availability of piggyBac vectors with manipulation flexibilities. Here, we seek to optimize piggyBac-mediated transgene expression and generate a more efficient, user-friendly piggyBac system. By engineering a panel of versatile piggyBac vectors and constructing recombinant adenoviruses expressing piggyBac transposase (PBase), we demonstrate that adenovirus-mediated PBase expression significantly enhances the integration efficiency and expression level of transgenes in mesenchymal stem cells and osteosarcoma cells, compared to that obtained from co-transfection of the CMV-PBase plasmid. We further determine the drug selection timeline to achieve optimal stable transgene expression. Moreover, we demonstrate that the transgene copy number of piggyBac-mediated integration is approximately 10 times higher than that mediated by retroviral vectors. Using the engineered tandem expression vector, we show that three transgenes can be simultaneously expressed in a single vector with high efficiency. Thus, these results strongly suggest that the optimized piggyBac system is a valuable tool for making stable cell lines with sustained, high transgene expression.

19.
J Biol Chem ; 290(18): 11741-8, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25792744

RESUMO

Small nucleolar RNAs (snoRNAs) guide nucleotide modifications of cellular RNAs in the nucleus. We previously showed that box C/D snoRNAs from the Rpl13a locus are unexpected mediators of physiologic oxidative stress, independent of their predicted ribosomal RNA modifications. Here we demonstrate that oxidative stress induced by doxorubicin causes rapid cytoplasmic accumulation of the Rpl13a snoRNAs through a mechanism that requires superoxide and a nuclear splice variant of NADPH oxidase. RNA-sequencing analysis reveals that box C/D snoRNAs as a class are present in the cytoplasm, where their levels are dynamically regulated by NADPH oxidase. These findings suggest that snoRNAs may orchestrate the response to environmental stress through molecular interactions outside of the nucleus.


Assuntos
Citosol/metabolismo , NADPH Oxidases/metabolismo , RNA Nucleolar Pequeno/metabolismo , Animais , Biocatálise , Transporte Biológico/efeitos dos fármacos , Citosol/efeitos dos fármacos , Doxorrubicina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , RNA Nucleolar Pequeno/genética , Ratos , Proteínas Ribossômicas/genética , Superóxidos/metabolismo
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