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1.
BMC Nurs ; 23(1): 317, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720346

RESUMO

Although there is a growing literature on the use of telepresence robots in institutional dementia care settings, limited research focused on the perspectives of frontline staff members who deliver dementia care. Our objective was to understand staff perspectives on using telepresence robots to support residents with dementia and their families. Guided by the Consolidated Framework for Implementation Research, we conducted four focus groups and 11 semi-structured interviews across four long-term care (LTC) homes and one hospital in Canada. We included 22 interdisciplinary staff members (e.g., registered nurses, social workers, occupational therapists, recreational therapists) to understand their experiences with telepresence robots. Thematic analysis identified three key themes: 1) Staff Training and Support; 2) Robot Features; 3) Environmental dynamics for Implementation. Our results underscore the imperative of structural support at micro-, meso- and macro-levels for staff in dementia care settings to effectively implement technology. This study contributes to future research and practice by elucidating factors facilitating staff involvement in technology research, integrating staff voices into technology implementation planning, and devising strategies to provide structural support to staff, care teams, and care homes.

2.
RNA ; 23(7): 1068-1079, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28373290

RESUMO

To identify regulators of pre-mRNA splicing in plants, we developed a forward genetic screen based on an alternatively spliced GFP reporter gene in Arabidopsis thaliana In wild-type plants, three major splice variants issue from the GFP gene but only one represents a translatable GFP mRNA. Compared to wild-type seedlings, which exhibit an intermediate level of GFP expression, mutants identified in the screen feature either a "GFP-weak" or "Hyper-GFP" phenotype depending on the ratio of the three splice variants. GFP-weak mutants, including previously identified prp8 and rtf2, contain a higher proportion of unspliced transcript or canonically spliced transcript, neither of which is translatable into GFP protein. In contrast, the coilin-deficient hyper-gfp1 (hgf1) mutant displays a higher proportion of translatable GFP mRNA, which arises from enhanced splicing of a U2-type intron with noncanonical AT-AC splice sites. Here we report three new hgf mutants that are defective, respectively, in spliceosome-associated proteins SMU1, SmF, and CWC16, an Yju2/CCDC130-related protein that has not yet been described in plants. The smu1 and cwc16 mutants have substantially increased levels of translatable GFP transcript owing to preferential splicing of the U2-type AT-AC intron, suggesting that SMU1 and CWC16 influence splice site selection in GFP pre-mRNA. Genome-wide analyses of splicing in smu1 and cwc16 mutants revealed a number of introns that were variably spliced from endogenous pre-mRNAs. These results indicate that SMU1 and CWC16, which are predicted to act directly prior to and during the first catalytic step of splicing, respectively, function more generally to modulate splicing patterns in plants.


Assuntos
Arabidopsis/genética , Proteínas Nucleares/metabolismo , RNA de Plantas/genética , Processamento Alternativo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Genes Reporter , Mutação , Proteínas Nucleares/genética
3.
Plant J ; 79(1): 127-38, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24798377

RESUMO

Short interfering RNAs (siRNAs) homologous to transcriptional regulatory regions can induce RNA-directed DNA methylation (RdDM) and transcriptional gene silencing (TGS) of target genes. In our system, siRNAs are produced by transcribing an inverted DNA repeat (IR) of enhancer sequences, yielding a hairpin RNA that is processed by several Dicer activities into siRNAs of 21-24 nt. Primarily 24-nt siRNAs trigger RdDM of the target enhancer in trans and TGS of a downstream GFP reporter gene. We analyzed siRNA accumulation from two different structural forms of a trans-silencer locus in which tandem repeats are embedded in the enhancer IR and distinguished distinct RNA polymerase II (Pol II)- and Pol IV-dependent pathways of siRNA biogenesis. At the original silencer locus, Pol-II transcription of the IR from a 35S promoter produces a hairpin RNA that is diced into abundant siRNAs of 21-24 nt. A silencer variant lacking the 35S promoter revealed a normally masked Pol IV-dependent pathway that produces low levels of 24-nt siRNAs from the tandem repeats. Both pathways operate concurrently at the original silencer locus. siRNAs accrue only from specific regions of the enhancer and embedded tandem repeat. Analysis of these sequences and endogenous tandem repeats producing siRNAs revealed the preferential accumulation of siRNAs at GC-rich regions containing methylated CG dinucleotides. In addition to supporting a correlation between base composition, DNA methylation and siRNA accumulation, our results highlight the complexity of siRNA biogenesis at repetitive loci and show that Pol II and Pol IV use different promoters to transcribe the same template.


Assuntos
Arabidopsis/genética , RNA Polimerases Dirigidas por DNA/genética , Regulação da Expressão Gênica de Plantas , RNA Polimerase II/genética , RNA Interferente Pequeno/genética , Sequências de Repetição em Tandem/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sequência de Bases , Metilação de DNA , RNA Polimerases Dirigidas por DNA/metabolismo , Inativação Gênica , Genes Reporter , Sequenciamento de Nucleotídeos em Larga Escala , Meristema/genética , Meristema/metabolismo , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Brotos de Planta/genética , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , RNA Polimerase II/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , RNA Interferente Pequeno/metabolismo , Análise de Sequência
4.
Nat Commun ; 13(1): 6302, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273204

RESUMO

Viewing faces that are perceived as emotionally expressive evokes enhanced neural responses in multiple brain regions, a phenomenon thought to depend critically on the amygdala. This emotion-related modulation is evident even in primary visual cortex (V1), providing a potential neural substrate by which emotionally salient stimuli can affect perception. How does emotional valence information, computed in the amygdala, reach V1? Here we use high-resolution functional MRI to investigate the layer profile and retinotopic distribution of neural activity specific to emotional facial expressions. Across three experiments, human participants viewed centrally presented face stimuli varying in emotional expression and performed a gender judgment task. We found that facial valence sensitivity was evident only in superficial cortical layers and was not restricted to the retinotopic location of the stimuli, consistent with diffuse feedback-like projections from the amygdala. Together, our results provide a feedback mechanism by which the amygdala directly modulates activity at the earliest stage of visual processing.


Assuntos
Expressão Facial , Córtex Visual , Humanos , Córtex Visual/fisiologia , Emoções/fisiologia , Tonsila do Cerebelo/fisiologia , Percepção Visual/fisiologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética
5.
Genetics ; 207(4): 1347-1359, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28971960

RESUMO

In a genetic screen for mutants showing modified splicing of an alternatively spliced GFP reporter gene in Arabidopsis thaliana, we identified mutations in genes encoding the putative U1 small nuclear ribonucleoprotein (snRNP) factors RBM25 and PRP39a. The latter has not yet been studied for its role in pre-messenger RNA (pre-mRNA) splicing in plants. Both proteins contain predicted RNA-binding domains and have been implicated in 5' splice site selection in yeast and metazoan cells. In rbm25 mutants, splicing efficiency of GFP pre-mRNA was reduced and GFP protein levels lowered relative to wild-type plants. By contrast, prp39a mutants exhibited preferential splicing of a U2-type AT-AC intron in GFP pre-mRNA and elevated levels of GFP protein. These opposing findings indicate that impaired function of either RBM25 or PRP39a can differentially affect the same pre-mRNA substrate. Given a prior genome-wide analysis of alternative splicing in rbm25 mutants, we focused on examining the alternative splicing landscape in prp39a mutants. RNA-seq experiments performed using two independent prp39a alleles revealed hundreds of common genes undergoing changes in alternative splicing, including PRP39a itself, a second putative U1 snRNP component PRP40b, and genes encoding a number of general transcription-related proteins. The prp39a mutants displayed somewhat delayed flowering, shorter stature, and reduced seed set but no other obvious common defects under normal conditions. Mutations in PRP39b, the paralog of PRP39a, did not visibly alter GFP expression, indicating the paralogs are not functionally equivalent in this system. Our study provides new information on the contribution of PRP39a to alternative splicing and expands knowledge of plant splicing factors.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas Mutantes/genética , Proteínas com Motivo de Reconhecimento de RNA/genética , Fatores de Processamento de RNA/genética , Splicing de RNA/genética , Proteínas de Ligação a RNA/genética , Processamento Alternativo/genética , Arabidopsis/genética , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , Íntrons/genética , Mutação , Proteínas Nucleares/genética , Precursores de RNA/genética , Sítios de Splice de RNA/genética , Ribonucleoproteína Nuclear Pequena U1/genética
6.
Genetics ; 203(4): 1709-20, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27317682

RESUMO

Coilin is a marker protein for subnuclear organelles known as Cajal bodies, which are sites of various RNA metabolic processes including the biogenesis of spliceosomal small nuclear ribonucleoprotein particles. Through self-associations and interactions with other proteins and RNA, coilin provides a structural scaffold for Cajal body formation. However, despite a conspicuous presence in Cajal bodies, most coilin is dispersed in the nucleoplasm and expressed in cell types that lack these organelles. The molecular function of coilin, particularly of the substantial nucleoplasmic fraction, remains uncertain. We identified coilin loss-of-function mutations in a genetic screen for mutants showing either reduced or enhanced expression of an alternatively spliced GFP reporter gene in Arabidopsis thaliana The coilin mutants feature enhanced GFP fluorescence and diminished Cajal bodies compared with wild-type plants. The amount of GFP protein is several-fold higher in the coilin mutants owing to elevated GFP transcript levels and more efficient splicing to produce a translatable GFP mRNA. Genome-wide RNA-sequencing data from two distinct coilin mutants revealed a small, shared subset of differentially expressed genes, many encoding stress-related proteins, and, unexpectedly, a trend toward increased splicing efficiency. These results suggest that coilin attenuates splicing and modulates transcription of a select group of genes. The transcriptional and splicing changes observed in coilin mutants are not accompanied by gross phenotypic abnormalities or dramatically altered stress responses, supporting a role for coilin in fine tuning gene expression. Our GFP reporter gene provides a sensitive monitor of coilin activity that will facilitate further investigations into the functions of this enigmatic protein.


Assuntos
Processamento Alternativo/genética , Proteínas de Arabidopsis/genética , Proteínas Mutantes/genética , Proteínas de Ligação a RNA/genética , RNA/genética , Arabidopsis/genética , Proteínas de Arabidopsis/biossíntese , Corpos Enovelados/genética , Regulação da Expressão Gênica de Plantas , Genes Reporter , Genoma de Planta , Proteínas de Fluorescência Verde/genética , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas Mutantes/biossíntese , Proteínas de Ligação a RNA/biossíntese , Spliceossomos/genética , Estresse Fisiológico/genética
7.
Case Rep Anesthesiol ; 2015: 897645, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26246916

RESUMO

We present the first documented case of Candida parapsilosis infective endocarditis in a pregnant patient. While the incidence of infective endocarditis during pregnancy is rare, the incidence of C. parapsilosis endocarditis is even rarer. The numerous specific risks and decision making processes regarding this case are presented.

8.
G3 (Bethesda) ; 5(9): 1849-55, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-26153075

RESUMO

Green fluorescent protein (GFP) and related fluorescent proteins are widely used in biological research to monitor gene expression and protein localization in living cells. The GFP chromophore is generated spontaneously in the presence of oxygen by a multi-step reaction involving cyclization of the internal tripeptide Ser65 (or Thr65)-Tyr66-Gly67, which is embedded in the center of an 11-stranded ß-barrel structure. Random and site-specific mutagenesis has been used to optimize GFP fluorescence and create derivatives with novel properties. However, loss-of-function mutations that would aid in understanding GFP protein folding and chromophore formation have not been fully cataloged. Here we report a collection of ethyl methansulfonate-induced GFP loss-of-function mutations in the model plant Arabidopsis thaliana. Mutations that alter residues important for chromophore maturation, such as Arg96 and Ser205, greatly reduce or extinguish fluorescence without dramatically altering GFP protein accumulation. By contrast, other loss-of-fluorescence mutations substantially diminish the amount of GFP protein, suggesting that they compromise protein stability. Many mutations in this category generate substitutions of highly conserved glycine residues, including the following: Gly67 in the chromogenic tripeptide; Gly31, Gly33, and Gly35 in the second ß-strand; and Gly20, Gly91, and Gly127 in the lids of the ß-barrel scaffold. Our genetic analysis supports conclusions from structural and biochemical studies and demonstrates a critical role for multiple, highly conserved glycine residues in GFP protein stability.


Assuntos
Arabidopsis/genética , Proteínas de Fluorescência Verde/genética , Mutação , Substituição de Aminoácidos , Códon sem Sentido , Sequência Conservada , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/metabolismo , Mutagênese , Plantas Geneticamente Modificadas , Dobramento de Proteína , Estabilidade Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
9.
G3 (Bethesda) ; 4(11): 2147-57, 2014 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-25193496

RESUMO

Coconut palm (Cocos nucifera) is a symbol of the tropics and a source of numerous edible and nonedible products of economic value. Despite its nutritional and industrial significance, coconut remains under-represented in public repositories for genomic and transcriptomic data. We report de novo transcript assembly from RNA-seq data and analysis of gene expression in seed tissues (embryo and endosperm) and leaves of a dwarf coconut variety. Assembly of 10 GB sequencing data for each tissue resulted in 58,211 total unigenes in embryo, 61,152 in endosperm, and 33,446 in leaf. Within each unigene pool, 24,857 could be annotated in embryo, 29,731 could be annotated in endosperm, and 26,064 could be annotated in leaf. A KEGG analysis identified 138, 138, and 139 pathways, respectively, in transcriptomes of embryo, endosperm, and leaf tissues. Given the extraordinarily large size of coconut seeds and the importance of small RNA-mediated epigenetic regulation during seed development in model plants, we used homology searches to identify putative homologs of factors required for RNA-directed DNA methylation in coconut. The findings suggest that RNA-directed DNA methylation is important during coconut seed development, particularly in maturing endosperm. This dataset will expand the genomics resources available for coconut and provide a foundation for more detailed analyses that may assist molecular breeding strategies aimed at improving this major tropical crop.


Assuntos
Cocos/genética , Metilação de DNA , Transcriptoma , Mapeamento de Sequências Contíguas , Anotação de Sequência Molecular , Folhas de Planta/metabolismo , Sementes/metabolismo , Análise de Sequência de RNA , Homologia de Sequência
10.
Drugs Aging ; 27(2): 149-58, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20104940

RESUMO

BACKGROUND: Despite evidence of effective combination drug therapy for secondary prevention of coronary heart disease (CHD), older adults with this condition remain undertreated. OBJECTIVE: To describe time trends (1992-2003) in the adoption of combination cardiac drug therapies (beta-blockers [beta-adrenoceptor antagonists], ACE inhibitors or angiotensin II type 1 receptor antagonists [angiotensin receptor blockers; ARBs], and lipid-lowering agents) among older adults in the US with CHD and to identify factors associated with not using combination therapy. METHODS: The study took the form of a cross-sectional time-series. The study population consisted of a nationally representative sample of adults aged >or=65 years with CHD (unweighted n = 6331; weighted n = 20.1 million) included in the 1992-2003 Medicare Current Beneficiary Survey. The outcome measure was low-intensity cardiac pharmacotherapy (no drug or single drug therapy with beta-blockers, ACE inhibitors/ARBs or lipid-lowering agents) compared with combination therapy (>or=2 cardiac drugs) for secondary CHD prevention. RESULTS: The use of combination drug therapy in older adults with CHD increased 9-fold during the study period (from 6% in 1992 to 54% in 2003). Adjusted analyses demonstrate that suboptimal drug therapy was independently associated with advanced age (relative risk [RR] 1.18; 95% CI 1.14, 1.23) for patients aged >or=85 years versus patients aged 65-74 years, and with being non-Hispanic Black (RR 1.05; 95% CI 1.01, 1.10) or Hispanic (RR 1.13; 95% CI 1.06, 1.21) versus being non-Hispanic White. CONCLUSIONS: Combination drug therapy use for secondary CHD prevention increased in older US adults over the last decade, but improvements were not uniform. The oldest-old, non-Hispanic Blacks and Hispanics experienced slower adoption of optimal medical therapy to improve their long-term prognosis for CHD.


Assuntos
Anti-Hipertensivos/administração & dosagem , Doença das Coronárias/tratamento farmacológico , Medicare , Padrões de Prática Médica , Antagonistas Adrenérgicos beta/uso terapêutico , Adulto , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Doença das Coronárias/prevenção & controle , Prescrições de Medicamentos , Quimioterapia Combinada/estatística & dados numéricos , Quimioterapia Combinada/tendências , Etnicidade , Humanos , Fatores Sexuais , Estados Unidos
11.
J Drug Target ; 17(3): 181-93, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19016072

RESUMO

Pegylation of gold nanoshells provides an effective means to reduce their reticuloendothelial system (RES) clearance in body. In this study, we perform a parametric investigation on the factors that would affect the macrophage uptake of gold nanoshells with the aim to optimize their pegylation and minimize their macrophage uptake. We synthesized and pegylated the gold nanoshells using methoxy-poly(ethylene glycol)-thiol and employed an in vitro macrophage assay to examine the effect of surface density of poly(ethylene glycol) (PEG), chain length of the PEG, and size of the gold nanoshells on their macrophage uptake. We have shown that a saturated surface density would minimize macrophage uptake, which could be obtained by experimental titration-based Ellman's reagent. Our results suggest that the chain length of PEG and size of gold nanoshells influence the surface density of PEG. We have also shown that PEG with molecular weight of around 2000Da and a size range larger than 186nm would be appropriate for facilitating a high surface density. Our in vitro macrophage system thus provides a good model to accurately predict the RES response to different pegylation parameters.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ouro/química , Ouro/farmacocinética , Macrófagos/metabolismo , Nanopartículas Metálicas/química , Polietilenoglicóis/química , Linhagem Celular Tumoral , Humanos , Macrófagos/citologia , Nanopartículas Metálicas/administração & dosagem , Modelos Biológicos , Tamanho da Partícula , Fagocitose/efeitos dos fármacos , Compostos de Sulfidrila/química , Propriedades de Superfície
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