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1.
Mol Cell ; 84(14): 2765-2784.e16, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38964322

RESUMEN

Dissecting the regulatory mechanisms controlling mammalian transcripts from production to degradation requires quantitative measurements of mRNA flow across the cell. We developed subcellular TimeLapse-seq to measure the rates at which RNAs are released from chromatin, exported from the nucleus, loaded onto polysomes, and degraded within the nucleus and cytoplasm in human and mouse cells. These rates varied substantially, yet transcripts from genes with related functions or targeted by the same transcription factors and RNA-binding proteins flowed across subcellular compartments with similar kinetics. Verifying these associations uncovered a link between DDX3X and nuclear export. For hundreds of RNA metabolism genes, most transcripts with retained introns were degraded by the nuclear exosome, while the remaining molecules were exported with stable cytoplasmic lifespans. Transcripts residing on chromatin for longer had extended poly(A) tails, whereas the reverse was observed for cytoplasmic mRNAs. Finally, machine learning identified molecular features that predicted the diverse life cycles of mRNAs.


Asunto(s)
Núcleo Celular , Cromatina , ARN Helicasas DEAD-box , ARN Mensajero , Animales , Humanos , Ratones , ARN Mensajero/metabolismo , ARN Mensajero/genética , Núcleo Celular/metabolismo , Núcleo Celular/genética , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Cromatina/metabolismo , Cromatina/genética , Citoplasma/metabolismo , Citoplasma/genética , Estabilidad del ARN , Transporte Activo de Núcleo Celular , Polirribosomas/metabolismo , Polirribosomas/genética , Aprendizaje Automático , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Exosomas/metabolismo , Exosomas/genética
2.
Nat Methods ; 19(11): 1393-1402, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36216958

RESUMEN

We present Light-Seq, an approach for multiplexed spatial indexing of intact biological samples using light-directed DNA barcoding in fixed cells and tissues followed by ex situ sequencing. Light-Seq combines spatially targeted, rapid photocrosslinking of DNA barcodes onto complementary DNAs in situ with a one-step DNA stitching reaction to create pooled, spatially indexed sequencing libraries. This light-directed barcoding enables in situ selection of multiple cell populations in intact fixed tissue samples for full-transcriptome sequencing based on location, morphology or protein stains, without cellular dissociation. Applying Light-Seq to mouse retinal sections, we recovered thousands of differentially enriched transcripts from three cellular layers and discovered biomarkers for a very rare neuronal subtype, dopaminergic amacrine cells, from only four to eight individual cells per section. Light-Seq provides an accessible workflow to combine in situ imaging and protein staining with next generation sequencing of the same cells, leaving the sample intact for further analysis post-sequencing.


Asunto(s)
ADN , Secuenciación de Nucleótidos de Alto Rendimiento , Animales , Ratones , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , ADN Complementario , ADN/genética
3.
Am J Otolaryngol ; 45(1): 104078, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37806280

RESUMEN

This article describes the first recorded case of intratemporal neurofibroma in an infant. A literature review of all other existing cases of intratemporal neurofibroma is performed, finding that the majority of cases involve multiple segments and can be found in the mastoid segment most often. Most common symptoms described included facial paralysis, otalgia, and conductive hearing loss, respectively.


Asunto(s)
Enfermedades del Nervio Facial , Parálisis Facial , Neurofibroma , Lactante , Humanos , Parálisis Facial/etiología , Nervio Facial , Enfermedades del Nervio Facial/diagnóstico , Enfermedades del Nervio Facial/etiología , Enfermedades del Nervio Facial/cirugía , Neurofibroma/complicaciones , Neurofibroma/diagnóstico , Neurofibroma/cirugía , Apófisis Mastoides , Hueso Temporal
4.
Dev Biol ; 481: 30-42, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34534525

RESUMEN

The bipolar interneurons of the mammalian retina have evolved as a diverse set of cells with distinct subtype characteristics, which reflect specialized contributions to visual circuitry. Fifteen subtypes of bipolar interneurons have been identified in the mouse retina, each with characteristic gene expression, morphology, and light responses. This review provides an overview of the developmental events that underlie the generation of the diverse bipolar cell class, summarizing the current knowledge of genetic programs that establish and maintain bipolar subtype fates, as well as the events that shape the final distribution of bipolar subtypes. With much left to be discovered, bipolar interneurons present an ideal model system for studying the interplay between cell-autonomous and non-cell-autonomous mechanisms that influence neuronal subtype development within the central nervous system.


Asunto(s)
Diferenciación Celular , Sistema Nervioso Central/embriología , Regulación del Desarrollo de la Expresión Génica , Neurogénesis , Retina/embriología , Células Bipolares de la Retina/metabolismo , Animales , Ratones
5.
Hum Mol Genet ; 29(22): 3706-3716, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33355362

RESUMEN

Mutations in retinitis pigmentosa GTPase regulator (RPGR) cause severe retinal ciliopathy, X-linked retinitis pigmentosa. Although two major alternatively spliced isoforms, RPGRex1-19 and RPGRORF15, are expressed, the relative importance of these isoforms in disease pathogenesis is unclear. Here, we analyzed fibroblast samples from eight patients and found that all of them form longer cilia than normal controls, albeit to different degrees. Although all mutant RPGRORF15 messenger RNAs (mRNAs) are unstable, their steady-state levels were similar or higher than those in the control cells, suggesting there may be increased transcription. Three of the fibroblasts that had higher levels of mutant RPGRORF15 mRNA also exhibited significantly higher levels of RPGRex1-19 mRNA. Four samples with unaltered RPGRex1-19 levels carried mutations in RPGRORF15 that resulted in this isoform being relatively less stable. Thus, in all cases, the RPGRex1-19/RPGRORF15 isoform ratio was increased, and this was highly correlative to the cilia extension defect. Moreover, overexpression of RPGRex1-19 (mimicking the increase in RPGRex1-19 to RPGRORF15 isoform ratio) or RPGRORF15 (mimicking reduction of the ratio) resulted in significantly longer or shorter cilia, respectively. Notably, the cilia length defect appears to be attributable to both the loss of the wild-type RPGRORF15 protein and to the higher levels of the RPGRex1-19 isoform, indicating that the observed defect is due to the altered isoform ratios. These results suggest that maintaining the optimal RPGRex1-9 to RPGRORF15 ratio is critical for cilia growth and that designing strategies that focus on the best ways to restore the RPGRex1-19/RPGRORF15 ratio may lead to better therapeutic outcomes.


Asunto(s)
Proteínas del Ojo/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Retinitis Pigmentosa/genética , Empalme Alternativo/genética , Proteínas Portadoras/genética , Cilios/genética , Cilios/patología , Exones/genética , Femenino , Fibroblastos , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Humanos , Masculino , Mutación/genética , Isoformas de Proteínas/genética , Retina/metabolismo , Retina/patología , Retinitis Pigmentosa/patología
6.
EMBO Rep ; 22(11): e53732, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34494703

RESUMEN

Neuronal communication is typically mediated via synapses and gap junctions. New forms of intercellular communication, including nanotubes (NTs) and extracellular vesicles (EVs), have been described for non-neuronal cells, but their role in neuronal communication is not known. Recently, transfer of cytoplasmic material between donor and host neurons ("material transfer") was shown to occur after photoreceptor transplantation. The cellular mechanism(s) underlying this surprising finding are unknown. Here, using transplantation, primary neuronal cultures and the generation of chimeric retinae, we show for the first time that mammalian photoreceptor neurons can form open-end NT-like processes. These processes permit the transfer of cytoplasmic and membrane-bound molecules in culture and after transplantation and can mediate gain-of-function in the acceptor cells. Rarely, organelles were also observed to transfer. Strikingly, use of chimeric retinae revealed that material transfer can occur between photoreceptors in the intact adult retina. Conversely, while photoreceptors are capable of releasing EVs, at least in culture, these are taken up by glia and not by retinal neurons. Our findings provide the first evidence of functional NT-like processes forming between sensory neurons in culture and in vivo.


Asunto(s)
Vesículas Extracelulares , Nanotubos , Animales , Comunicación Celular , Mamíferos , Neuronas , Retina
7.
BMC Med Educ ; 23(1): 817, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37907938

RESUMEN

BACKGROUND: Building clinician and organisation-level research translation capacity and capability is fundamental for increasing the implementation of research into health practice and policy and improving health outcomes. Research translation capacity and capability building is particularly crucial in rural and regional settings to address complex problems impacting these socially and economically disadvantaged communities. Programs to build clinicians' research translation capability typically involve training and mentoring. Little is known about the features of and influences on mentorships in the context of training for emerging clinician-researchers working in rural and regional healthcare settings. Research translation mentorships were established as part of the Supporting Translation Research in Rural and Regional settings (STaRR) program developed and delivered in Victoria, Australia from 2020 to 2021. The study sought to address the following research questions: 1) What context-specific types of support do research translation mentors provide to emerging researchers?. 2) How does the mentoring element of a rural research translational training program influence research translation capacity and capability development in rural emerging researchers and mentors, if at all?. 3) How does the mentoring element of the program influence translation capacity and capability at the organisational and regional level, if at all? METHODS: We conducted a qualitative descriptive study. Interviews with individuals involved in the STaRR program took place approximately 12 months after the program and explored participants' experiences of the mentored training. Interviews were undertaken via telephone, audio-recorded, and transcribed. Data were analysed using a team-based five-stage framework approach. RESULTS: Participants included emerging researchers (n = 9), mentors (n = 5), and managers (n = 4), from five health services and two universities. We identified four themes in the interview data: (1) Mentors play an educative role; (2) Mentoring enhanced by a collaborative environment; (3) Organisational challenges can influence mentorships, and (4) Mentorships help develop research networks and collective research and translation capacity. CONCLUSIONS: Mentorships contributed to the development of research translation capabilities. The capabilities were developed through mentors' deepened understanding of the rural and regional healthcare contexts in which their emerging researchers worked, the broadening and strengthening of rural and regional research networks, and building and sharing research translation knowledge and skills.


Asunto(s)
Tutoría , Mentores , Humanos , Investigación Cualitativa , Investigación Biomédica Traslacional , Atención a la Salud
8.
Nat Methods ; 16(6): 533-544, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31110282

RESUMEN

Fluorescence in situ hybridization (FISH) reveals the abundance and positioning of nucleic acid sequences in fixed samples. Despite recent advances in multiplexed amplification of FISH signals, it remains challenging to achieve high levels of simultaneous amplification and sequential detection with high sampling efficiency and simple workflows. Here we introduce signal amplification by exchange reaction (SABER), which endows oligonucleotide-based FISH probes with long, single-stranded DNA concatemers that aggregate a multitude of short complementary fluorescent imager strands. We show that SABER amplified RNA and DNA FISH signals (5- to 450-fold) in fixed cells and tissues. We also applied 17 orthogonal amplifiers against chromosomal targets simultaneously and detected mRNAs with high efficiency. We then used 10-plex SABER-FISH to identify in vivo introduced enhancers with cell-type-specific activity in the mouse retina. SABER represents a simple and versatile molecular toolkit for rapid and cost-effective multiplexed imaging of nucleic acid targets.


Asunto(s)
ADN/análisis , Colorantes Fluorescentes/metabolismo , Hibridación Fluorescente in Situ/métodos , Oligonucleótidos/química , Imagen Óptica/métodos , ARN/análisis , Retina/metabolismo , Animales , Células Cultivadas , ADN/genética , ADN de Cadena Simple/química , Humanos , Ratones , ARN/genética , Retina/diagnóstico por imagen
9.
Calcif Tissue Int ; 110(6): 649-657, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35028685

RESUMEN

Accumulation of fat in the liver and skeletal muscle is associated with obesity and poor health outcomes. Liver steatosis is a characteristic of non-alcoholic fatty liver disease (NAFLD) and myosteatosis, of poor muscle quality in sarcopenia. In this study of 403 men (33-96 years), we investigated associations between the fatty liver index (FLI) and muscle density, as markers of fat accumulation in these organs. We also investigated associations between the FLI and parameters of sarcopenia, including DXA-derived appendicular lean mass (ALM) and handgrip strength by dynamometry. Muscle density was measured using pQCT at the radius and tibia. FLI was calculated from BMI, waist circumference, and levels of triglycerides and gamma-glutamyltransferase. There was a pattern of decreasing muscle density across increasing quartiles of FLI. After adjusting for age and lifestyle, mean radial muscle density in Q4 was 2.1% lower than Q1 (p < 0.001) and mean tibial muscle density was 1.8% lower in Q3 and 3.0% lower in Q4, compared to Q1 (p = 0.022 and < 0.001, respectively). After adjusting for age and sedentary lifestyle, participants in the highest FLI quartile were sixfold more likely to have sarcopenia. In conclusion, our results suggest that fat accumulation in the liver co-exists with fat infiltration into skeletal muscle.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Sarcopenia , Índice de Masa Corporal , Fuerza de la Mano , Humanos , Masculino , Músculo Esquelético/patología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/patología , Sarcopenia/complicaciones , Circunferencia de la Cintura
10.
BMC Med Educ ; 22(1): 385, 2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35590359

RESUMEN

BACKGROUND: Research capacity building (RCB) initiatives have gained steady momentum in health settings across the globe to reduce the gap between research evidence and health practice and policy. RCB strategies are typically multidimensional, comprising several initiatives targeted at different levels within health organisations. Research education and training is a mainstay strategy targeted at the individual level and yet, the evidence for research education in health settings is unclear. This review scopes the literature on research education programs for nurses and allied health professionals, delivered and evaluated in healthcare settings in high-income countries. METHODS: The review was conducted systematically in accordance with the Joanna Briggs Institute scoping review methodology. Eleven academic databases and numerous grey literature platforms were searched. Data were extracted from the included full texts in accordance with the aims of the scoping review. A narrative approach was used to synthesise findings. Program characteristics, approaches to program evaluation and the outcomes reported were extracted and summarised. RESULTS: Database searches for peer-reviewed and grey literature yielded 12,457 unique records. Following abstract and title screening, 207 full texts were reviewed. Of these, 60 records were included. Nine additional records were identified on forward and backward citation searching for the included records, resulting in a total of 69 papers describing 68 research education programs. Research education programs were implemented in fourteen different high-income countries over five decades. Programs were multifaceted, often encompassed experiential learning, with half including a mentoring component. Outcome measures largely reflected lower levels of Barr and colleagues' modified Kirkpatrick educational outcomes typology (e.g., satisfaction, improved research knowledge and confidence), with few evaluated objectively using traditional research milestones (e.g., protocol completion, manuscript preparation, poster, conference presentation). Few programs were evaluated using organisational and practice outcomes. Overall, evaluation methods were poorly described. CONCLUSION: Research education remains a key strategy to build research capacity for nurses and allied health professionals working in healthcare settings. Evaluation of research education programs needs to be rigorous and, although targeted at the individual, must consider longer-term and broader organisation-level outcomes and impacts. Examining this is critical to improving clinician-led health research and the translation of research into clinical practice.


Asunto(s)
Técnicos Medios en Salud , Competencia Clínica , Atención a la Salud , Escolaridad , Humanos
11.
Am J Otolaryngol ; 42(2): 102862, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33429177

RESUMEN

INTRODUCTION: Facial pain is a common manifestation of sinonasal disease but may be due to a variety of other conditions. Misattribution of pain to chronic rhinosinusitis may result in worse quality of life in populations both with and without objective evidence of sinonasal disease. The purpose of this study was to determine if there is an association between pain-related comorbidities and worse chronic rhinosinusitis specific quality of life in patients with and without objective evidence of sinonasal inflammation. METHODS: Retrospective cohort study of 299 patients meeting diagnostic criteria for sinusitis evaluated at a tertiary academic medical center from 2017 to 2018. Objective evidence was measured using the Lund-Kennedy and Lund-MacKay scoring systems; for the purposes of this study a score >3 on either scale was considered indicative of disease. Quality of life was determined by the rhinosinusitis disability index. RESULTS: A total of 191 patients were included in the study, with an average age of 52.7. (SD=15.3). The average Lund-Kennedy and Lund-MacKay scores were 4.7 and 8.3, respectively. The average rhinosinusitis disability index was 32.1. When stratified by the presence of pain-related comorbidities, there was no significant difference in Lund-Kennedy (p = 0.203), Lund-MacKay (p = 0.101), or rhinosinusitis disability index (p = 0.421). CONCLUSION: Although prior studies have suggested a correlation between the presence of pain-related comorbidities and worse chronic rhinosinusitis specific quality of life, this relationship was not evident within the current cohort of patients. The relationship between pain and sinusitis specific quality of life is likely complex and requires further research to fully elucidate.


Asunto(s)
Dolor/epidemiología , Calidad de Vida , Rinitis/diagnóstico , Rinitis/epidemiología , Sinusitis/diagnóstico , Sinusitis/epidemiología , Adulto , Anciano , Enfermedad Crónica , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
12.
BMC Health Serv Res ; 19(1): 680, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31533698

RESUMEN

BACKGROUND: To evaluate the impact of the Dementia Care in Hospitals Program (DCHP) on clinical and non-clinical staff job satisfaction, level of confidence and comfort in caring for patients with cognitive impairment (CI). Staff perceptions of how organisational support and hospital environment met the needs of patients with CI were also assessed. METHODS: The DCHP was implemented across four acute hospital sites across Australia. Clinical and non-clinical staff received training on CI screening and communication strategies for patients with CI. A staff satisfaction survey was administered pre- and post-implementation of the DCHP. RESULTS: One thousand seven hundred forty-eight staff received DCHP education and 1375 staff participated in the survey. Self-reported confidence and level of comfort in caring for patients with CI significantly improved following implementation. Staff also reported increased job satisfaction and organisational support at all hospital sites. CONCLUSIONS: The DCHP implementation within an acute hospital setting was found to show an improvement in staff confidence, comfort, and job satisfaction when caring for patients with CI. This study has significant implications for the improvement of care for patients with CI as well as staff retention and job satisfaction. Further research is required to determine whether these improvements are sustained in the longer term.


Asunto(s)
Demencia/terapia , Satisfacción en el Trabajo , Satisfacción Personal , Personal de Hospital/psicología , Actitud del Personal de Salud , Australia , Disfunción Cognitiva/terapia , Comunicación , Femenino , Hospitales , Humanos , Masculino , Persona de Mediana Edad , Cultura Organizacional , Personal de Hospital/educación , Apoyo Social , Encuestas y Cuestionarios
13.
Stem Cells ; 33(8): 2469-82, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25982268

RESUMEN

Loss of photoreceptors due to retinal degeneration is a major cause of untreatable blindness. Cell replacement therapy, using pluripotent stem cell-derived photoreceptor cells, may be a feasible future treatment. Achieving safe and effective cell replacement is critically dependent on the stringent selection and purification of optimal cells for transplantation. Previously, we demonstrated effective transplantation of post-mitotic photoreceptor precursor cells labelled by fluorescent reporter genes. As genetically labelled cells are not desirable for therapy, here we developed a surface biomarker cell selection strategy for application to complex pluripotent stem cell differentiation cultures. We show that a five cell surface biomarker panel CD73(+)CD24(+)CD133(+)CD47(+)CD15(-) facilitates the isolation of photoreceptor precursors from three-dimensional self-forming retina differentiated from mouse embryonic stem cells. Importantly, stem cell-derived cells isolated using the biomarker panel successfully integrate and mature into new rod photoreceptors in the adult mouse retinae after subretinal transplantation. Conversely, unsorted or negatively selected cells do not give rise to newly integrated rods after transplantation. The biomarker panel also removes detrimental proliferating cells prior to transplantation. Notably, we demonstrate how expression of the biomarker panel is conserved in the human retina and propose that a similar selection strategy will facilitate isolation of human transplantation-competent cells for therapeutic application.


Asunto(s)
Antígenos de Diferenciación/metabolismo , Células Madre Embrionarias de Ratones/metabolismo , Degeneración Retiniana/terapia , Células Fotorreceptoras Retinianas Bastones , Trasplante de Células Madre , Animales , Humanos , Ratones , Degeneración Retiniana/metabolismo , Células Fotorreceptoras Retinianas Bastones/metabolismo , Células Fotorreceptoras Retinianas Bastones/trasplante
14.
Proc Natl Acad Sci U S A ; 110(1): 354-9, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-23248312

RESUMEN

Despite different aetiologies, age-related macular degeneration and most inherited retinal disorders culminate in the same final common pathway, the loss of photoreceptors. There are few treatments and none reverse the loss of vision. Photoreceptor replacement by transplantation is proposed as a broad treatment strategy applicable to all degenerations. Recently, we demonstrated restoration of vision following rod-photoreceptor transplantation into a mouse model of stationary night-blindness, raising the critical question of whether photoreceptor replacement is equally effective in different types and stages of degeneration. We present a comprehensive assessment of rod-photoreceptor transplantation across six murine models of inherited photoreceptor degeneration. Transplantation is feasible in all models examined but disease type has a major impact on outcome, as assessed both by the morphology and number of integrated rod-photoreceptors. Integration can increase (Prph2(+/Δ307)), decrease (Crb1(rd8/rd8), Gnat1(-/-), Rho(-/-)), or remain constant (PDE6ß(rd1/rd1), Prph2(rd2/rd2)) with disease progression, depending upon the gene defect, with no correlation with severity. Robust integration is possible even in late-stage disease. Glial scarring and outer limiting membrane integrity, features that change with degeneration, significantly affect transplanted photoreceptor integration. Combined breakdown of these barriers markedly increases integration in a model with an intact outer limiting membrane, strong gliotic response, and otherwise poor transplantation outcome (Rho(-/-)), leading to an eightfold increase in integration and restoration of visual function. Thus, it is possible to achieve robust integration across a broad range of inherited retinopathies. Moreover, transplantation outcome can be improved by administering appropriate, tailored manipulations of the recipient environment.


Asunto(s)
Ceguera Nocturna/cirugía , Atrofia Óptica Hereditaria de Leber/cirugía , Células Fotorreceptoras Retinianas Bastones/trasplante , Retinitis Pigmentosa/cirugía , Animales , Western Blotting , Recuento de Células , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 6/metabolismo , Citometría de Flujo , Subunidades alfa de la Proteína de Unión al GTP/genética , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Proteínas de Filamentos Intermediarios/metabolismo , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Confocal , Microscopía Electrónica de Transmisión , Proteínas del Tejido Nervioso/metabolismo , Ceguera Nocturna/genética , Atrofia Óptica Hereditaria de Leber/genética , Periferinas , Células Fotorreceptoras Retinianas Bastones/ultraestructura , Retinitis Pigmentosa/genética , Transducina/genética , Transducina/metabolismo , Resultado del Tratamiento , Proteínas de Unión al GTP rho/genética , Proteínas de Unión al GTP rho/metabolismo
15.
Development ; 139(13): 2340-50, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22627278

RESUMEN

Molecular oxygen is essential for the development, growth and survival of multicellular organisms. Hypoxic microenvironments and oxygen gradients are generated physiologically during embryogenesis and organogenesis. In the eye, oxygen plays a crucial role in both physiological vascular development and common blinding diseases. The retinal pigment epithelium (RPE) is a monolayer of cells essential for normal ocular development and in the mature retina provides support for overlying photoreceptors and their vascular supply. Hypoxia at the level of the RPE is closely implicated in pathogenesis of age-related macular degeneration. Adaptive tissue responses to hypoxia are orchestrated by sophisticated oxygen sensing mechanisms. In particular, the von Hippel-Lindau tumour suppressor protein (pVhl) controls hypoxia-inducible transcription factor (HIF)-mediated adaptation. However, the role of Vhl/Hif1a in the RPE in the development of the eye and its vasculature is unknown. In this study we explored the function of Vhl and Hif1a in the developing RPE using a tissue-specific conditional-knockout approach. We found that deletion of Vhl in the RPE results in RPE apoptosis, aniridia and microphthalmia. Increased levels of Hif1a, Hif2a, Epo and Vegf are associated with a highly disorganised retinal vasculature, chorioretinal anastomoses and the persistence of embryonic vascular structures into adulthood. Additional inactivation of Hif1a in the RPE rescues the RPE morphology, aniridia, microphthalmia and anterior vasoproliferation, but does not rescue retinal vasoproliferation. These data demonstrate that Vhl-dependent regulation of Hif1a in the RPE is essential for normal RPE and iris development, ocular growth and vascular development in the anterior chamber, whereas Vhl-dependent regulation of other downstream pathways is crucial for normal development and maintenance of the retinal vasculature.


Asunto(s)
Ojo/crecimiento & desarrollo , Subunidad alfa del Factor 1 Inducible por Hipoxia/fisiología , Epitelio Pigmentado de la Retina/crecimiento & desarrollo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/fisiología , Animales , Aniridia/genética , Aniridia/patología , Apoptosis/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/análisis , Proliferación Celular , Electrorretinografía , Eritropoyetina/metabolismo , Ojo/irrigación sanguínea , Ojo/citología , Eliminación de Gen , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microftalmía/genética , Microftalmía/patología , Epitelio Pigmentado de la Retina/citología , Factor A de Crecimiento Endotelial Vascular/análisis , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética
16.
Implement Sci ; 19(1): 7, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287351

RESUMEN

BACKGROUND: Building healthcare service and health professionals' capacity and capability to rapidly translate research evidence into health practice is critical to the effectiveness and sustainability of healthcare systems. This review scoped the literature describing programmes to build knowledge translation capacity and capability in health professionals and healthcare services, and the evidence supporting these. METHODS: This scoping review was undertaken using the Joanna Briggs Institute scoping review methodology. Four research databases (Ovid MEDLINE, CINAHL, Embase, and PsycInfo) were searched using a pre-determined strategy. Eligible studies described a programme implemented in healthcare settings to build health professional or healthcare service knowledge translation capacity and capability. Abstracts and full texts considered for inclusion were screened by two researchers. Data from included papers were extracted using a bespoke tool informed by the scoping review questions. RESULTS: Database searches yielded 10,509 unique citations, of which 136 full texts were reviewed. Thirty-four papers were included, with three additional papers identified on citation searching, resulting in 37 papers describing 34 knowledge translation capability building programmes. Programmes were often multifaceted, comprising a combination of two or more strategies including education, dedicated implementation support roles, strategic research-practice partnerships and collaborations, co-designed knowledge translation capability building programmes, and dedicated funding for knowledge translation. Many programmes utilised experiential and collaborative learning, and targeted either individual, team, organisational, or system levels of impact. Twenty-seven programmes were evaluated formally using one or more data collection methods. Outcomes measured varied significantly and included participant self-reported outcomes, perceived barriers and enablers of knowledge translation, milestone achievement and behaviour change. All papers reported that programme objectives were achieved to varying degrees. CONCLUSIONS: Knowledge translation capacity and capability building programmes in healthcare settings are multifaceted, often include education to facilitate experiential and collaborative learning, and target individual, team, organisational, or supra-organisational levels of impact. Although measured differently across the programmes, the outcomes were positive. The sustainability of programmes and outcomes may be undermined by the lack of long-term funding and inconsistent evaluation. Future research is required to develop evidence-informed frameworks to guide methods and outcome measures for short-, medium- and longer-term programme evaluation at the different structural levels.


Asunto(s)
Personal de Salud , Ciencia Traslacional Biomédica , Humanos , Atención a la Salud , Servicios de Salud , Organizaciones , Creación de Capacidad
17.
medRxiv ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39072030

RESUMEN

Posttraumatic Stress Disorder (PTSD) is a heterogeneous mental health disorder that occurs following traumatic experience. Understanding its neurobiological basis is crucial to advance early diagnosis and treatment. Electroencephalography (EEG) can be used to explore the neurobiological basis of PTSD. However, only limited research has explored mobile EEG, which is important for scalability. This proof-of-concept study delves into mobile EEG-derived biomarkers for PTSD and their potential implications. Over four weeks, we measured PTSD symptoms using the PTSD checklist for DSM-5 (PCL-5) at multiple timepoints, and we recorded multiple EEG sessions from 21 individuals using a mobile EEG device. In total, we captured 38 EEG sessions, each comprising two recordings that lasted approximately 180 seconds, to evaluate reproducibility. Next, we extracted Shannon entropy, as a measure of the randomness or unpredictability of the signal and spectral power for the fronto-temporal regions of interest, including electrodes at AF3, AF4, T7, and T8 for each EEG recording session. We calculated the partial correlation between the EEG variables and PCL-5 measured closest to the EEG session, using age, sex, and the grouping variable 'batch' as covariates. We observed a significant negative correlation between Shannon entropy in fronto-temporal regions and PCL-5 scores. Specifically, this association was evident in the AF3 (r = -0.456, FDR-corrected p = 0.01), AF4 (r = -0.362, FDR-corrected p = 0.04), and T7 (r = -0.472, FDR-corrected p = 0.01) regions. Additionally, we found a significant negative association between the alpha power estimated from AF4 and PCL-5 (r=-0.429, FDR-corrected p=0.04). Our findings suggest that EEG data acquired using a mobile EEG device is associated with PTSD symptom severity, offering valuable insights into the neurobiological mechanisms underlying PTSD.

18.
Stem Cells ; 30(7): 1424-35, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22570183

RESUMEN

Retinal degeneration is a leading cause of irreversible blindness in the developed world. Differentiation of retinal cells, including photoreceptors, from both mouse and human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), potentially provide a renewable source of cells for retinal transplantation. Previously, we have shown both the functional integration of transplanted rod photoreceptor precursors, isolated from the postnatal retina, in the adult murine retina, and photoreceptor cell generation by stepwise treatment of ESCs with defined factors. In this study, we assessed the extent to which this protocol recapitulates retinal development and also evaluated differentiation and integration of ESC-derived retinal cells following transplantation using our established procedures. Optimized retinal differentiation via isolation of Rax.GFP retinal progenitors recreated a retinal niche and increased the yield of Crx(+) and Rhodopsin(+) photoreceptors. Rod birth peaked at day 20 of culture and expression of the early photoreceptor markers Crx and Nrl increased until day 28. Nrl levels were low in ESC-derived populations compared with developing retinae. Transplantation of early stage retinal cultures produced large tumors, which were avoided by prolonged retinal differentiation (up to day 28) prior to transplantation. Integrated mature photoreceptors were not observed in the adult retina, even when more than 60% of transplanted ESC-derived cells expressed Crx. We conclude that exclusion of proliferative cells from ESC-derived cultures is essential for effective transplantation. Despite showing expression profiles characteristic of immature photoreceptors, the ESC-derived precursors generated using this protocol did not display transplantation competence equivalent to precursors from the postnatal retina.


Asunto(s)
Células Madre Embrionarias/citología , Células Fotorreceptoras/citología , Animales , Células Cultivadas , Células Madre Embrionarias/metabolismo , Citometría de Flujo , Inmunohistoquímica , Ratones , Células Fotorreceptoras/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Retina/citología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trasplante de Células Madre
19.
BMJ Open ; 13(12): e073556, 2023 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-38072488

RESUMEN

OBJECTIVES: The abbreviated World Health Organisation Quality of Life tool (WHOQOL-BREF) is a short-form quality of life (QoL) assessment commonly used worldwide in both healthy and ill populations. Normative data for the Australian general population are limited. The objective of this study was to present normative data for the WHOQOL-BREF based on a general population sample. A secondary aim was to explore sociodemographic factors related to QoL. DESIGN: Population-based cross-sectional study. PARTICIPANTS: 929 men and 830 women aged 24-94 years participating in the Geelong Osteoporosis Study. OUTCOME MEASURES: The 26-item WHOQOL-BREF. RESULTS: Means and SD for each domain are presented by age group and sex. Percentile scores were also generated. Mean scores for WHOQOL-BREF domains were 74.52 (SD=16.22) for physical health, 72.07 (SD=15.35) for psychological, 72.87 (SD=18.78) for social relationships and 79.68 (SD=12.55) for environment. We identified significant associations between sociodemographic factors and WHOQOL-BREF domains. Notably, being married or in a relationship was associated with increased odds for high QoL across all four WHOQOL-BREF domains: physical health (women OR 2.46, 95% CI 1.36 to 4.44, p=0.003), psychological (men OR 2.07, 95% CI: 1.20 to 3.55, p=0.009; women OR 2.15, 95% CI 1.21 to 3.81, p=0.009), social relationships (men OR 2.28, 95% CI 1.29 to 4.04, p=0.005; women OR 2.77, 95% CI 1.42 to 5.41, p=0.003) and environment (women OR 2.07, 95% CI 1.13 to 3.80, p=0.019). CONCLUSIONS: This study provides population norms for the WHOQOL-BREF based on a representative sample of Australian adults. Our results will be useful to researchers and clinicians who can use these data as a reference point for interpreting WHOQOL-BREF scores.


Asunto(s)
Estado de Salud , Calidad de Vida , Adulto , Masculino , Humanos , Femenino , Calidad de Vida/psicología , Estudios Transversales , Australia , Organización Mundial de la Salud , Encuestas y Cuestionarios , Psicometría/métodos
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