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1.
Anal Bioanal Chem ; 413(10): 2735-2745, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33078250

RESUMEN

Ischemic stroke is one of the major causes of death and permanent disability in the world. However, the molecular mechanisms surrounding tissue damage are complex and further studies are needed to gain insights necessary for development of treatment. Prophylactic treatment by administration of cytosine-guanine (CpG) oligodeoxynucleotides has been shown to provide neuroprotection against anticipated ischemic injury. CpG binds to Toll-like receptor 9 (TLR9) causing initialization of an inflammatory response that limits visible ischemic damages upon subsequent stroke. Here, we use nanospray desorption electrospray ionization (nano-DESI) mass spectrometry imaging (MSI) to characterize molecular effects of CpG preconditioning prior to middle cerebral artery occlusion (MCAO) and reperfusion. By doping the nano-DESI solvent with appropriate internal standards, we can study and compare distributions of phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) in the ischemic hemisphere of the brain despite the large changes in alkali metal abundances. Our results show that CpG preconditioning not only reduces the infarct size but it also decreases the degradation of PC and accumulation of LPC species, which indicates reduced cell membrane breakdown and overall ischemic damage. Our findings show that molecular mechanisms of PC degradation are intact despite CpG preconditioning but that these are limited due to the initialized inflammatory response.


Asunto(s)
Química Encefálica , Encéfalo/patología , Infarto de la Arteria Cerebral Media/terapia , Lisofosfatidilcolinas/análisis , Oligodesoxirribonucleótidos/uso terapéutico , Animales , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/patología , Masculino , Espectrometría de Masas , Ratones Endogámicos C57BL , Oligodesoxirribonucleótidos/administración & dosificación
2.
BMC Geriatr ; 21(1): 145, 2021 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-33639856

RESUMEN

BACKGROUND: Older adults want to live at home as long as possible, even in the face of circumstances that limit their autonomy. Home care services reflect this emergent preference, allowing older adults to 'age in place' in familiar settings rather than receiving care for chronic health conditions or ageing needs in an institutionalized setting. Numerous social factors, generally studied in isolation, have been associated with home care utilization. Even so, social circumstances are complex and how these factors collectively influence home care use patterns remains unclear. OBJECTIVES: To provide a broad and comprehensive overview of the social factors influencing home care utilization; and to evaluate the influence of discrete social factors on patterns of home care utilization in community-dwelling older adults in high-income countries. METHODS: A scoping review was conducted of six electronic databases for records published between 2010 and 2020; additional records were obtained from hand searching review articles, reference lists of included studies and documents from international organisations. A narrative synthesis was presented, complemented by vote counting per social factor, harvest plots and an evaluation of aggregated findings to determine consistency across studies. RESULTS: A total of 2,365 records were identified, of which 66 met inclusion criteria. There were 35 discrete social factors grouped into four levels of influence using a socio-ecological model (individual, relationship, community and societal levels) and grouped according to outcome of interest (home care propensity and intensity). Across all studies, social factors consistently showing any association (positive, negative, or equivocal in pattern) with home care propensity were: age, ethnicity/race, self-assessed health, insurance, housing ownership, housing problems, marital status, household income, children, informal caregiving, social networks and urban/rural area. Age, education, personal finances, living arrangements and housing ownership were associated with home care intensity, also with variable patterns in utilization. Additional community and societal level factors were identified as relevant but lacking consistency across the literature; these included rurality, availability of community services, methods of financing home care systems, and cultural determinants. CONCLUSION: This is the first literature review bringing together a wide range of reported social factors that influence home care utilization. It confirms social factors do influence home care utilization in complex interactions, distinguishes level of influences at which these factors affect patterns of use and discusses policy implications for home care reform.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Vida Independiente , Anciano , Escolaridad , Vivienda , Humanos , Factores Sociales
3.
BMC Health Serv Res ; 20(1): 535, 2020 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-32532268

RESUMEN

BACKGROUND: Enhancing non-clinical home care supports and services for older adults to live well is a strategic priority in developed countries, including Canada. Underpinning these supports and services are structures of care that are reflected in home care policies, programs and practices within jurisdictions. These approaches to care exist at multiple levels and inform interactions, perceptions, and care assessment, planning and provision, ultimately shaping the supports that are delivered. Jurisdictional differences in approaches to care mean that pathways through home care systems may differ, depending on where one lives. The goal of this study is to understand how approaches to care shape the pathways of older adult home care clients with chronic and long term conditions in two Canadian health jurisdictions. METHODS: This longitudinal mixed-methods study has three interrelated research streams informed by aspects of the socio-ecological framework. We will examine client pathways using a retrospective analysis of home care assessment data (Resident Assessment Instrument- Home Care) in two health authorities (Client/Service Data Stream). We will analyze interview data from older adult home care clients and a cluster of each client's family or friend caregiver(s), home support worker(s), care/case coordinator(s) and potentially other professionals at up to three points over 18 months using a prospective qualitative comparative case study design (Constellation Data Stream). We will review home care policies relevant to both health authorities and interview key informants regarding the creation and implementation of policies (Policy Stream). Our study will apply an integrated knowledge translation (iKT) approach that engages knowledge users in research design, analysis and interpretation to facilitate relevancy of results. DISCUSSION: Applying a mixed-method research design to understand approaches to care within and between two jurisdictions will contribute to the evidence base on older adult home care client pathways. Study results will identify how potential differences are experienced by clients and their families. An understanding of the policies will help to contextualize these findings. The iKT model will ensure that findings are useful for strategic planning and decision-making, and supporting changes in care practice.


Asunto(s)
Vías Clínicas , Servicios de Atención de Salud a Domicilio , Proyectos de Investigación , Anciano , Canadá , Cuidadores , Estudios de Casos y Controles , Toma de Decisiones , Atención a la Salud , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Planificación de Atención al Paciente , Estudios Prospectivos , Estudios Retrospectivos , Investigación Biomédica Traslacional
4.
Stroke ; 47(1): 262-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26564103

RESUMEN

BACKGROUND AND PURPOSE: Preconditioning with poly-l-lysine and carboxymethylcellulose (ICLC) provides robust neuroprotection from cerebral ischemia in a mouse stroke model. However, the receptor that mediates neuroprotection is unknown. As a synthetic double-stranded RNA, poly-ICLC may bind endosomal Toll-like receptor 3 or one of the cytosolic retinoic acid-inducible gene-I-like receptor family members, retinoic acid-inducible gene-I, or melanoma differentiation-associated protein 5. Activation of these receptors culminates in type I interferons (IFN-α/ß) induction-a response required for poly-ICLC-induced neuroprotection. In this study, we investigate the receptor required for poly-ICLC-induced neuroprotection. METHODS: Toll-like receptor 3, melanoma differentiation-associated protein 5-, and IFN-promoter stimulator 1-deficient mice were treated with poly-ICLC 24 hours before middle cerebral artery occlusion. Infarct volume was measured 24 hours after stroke to identify the receptor signaling pathways involved in protection. IFN-α/ß induction was measured in plasma samples collected 6 hours after poly-ICLC treatment. IFN-ß-deficient mice were used to test the requirement of IFN-ß for poly-ICLC-induced neuroprotection. Mice were treated with recombinant IFN-α-A to test the role of IFN-α as a potential mediator of neuroprotection. RESULTS: Poly-ICLC induction of both neuroprotection and systemic IFN-α/ß requires the cytosolic receptor melanoma differentiation-associated protein 5 and the adapter molecule IFN-promoter stimulator 1, whereas it is independent of Toll-like receptor 3. IFN-ß is not required for poly-ICLC-induced neuroprotection. IFN-α treatment protects against stroke. CONCLUSIONS: Poly-ICLC preconditioning is mediated by melanoma differentiation-associated protein 5 and its adaptor molecule IFN-promoter stimulator 1. This is the first evidence that a cytosolic receptor can mediate neuroprotection, providing a new target for the development of therapeutic agents to protect the brain from ischemic injury.


Asunto(s)
Isquemia Encefálica/metabolismo , Isquemia Encefálica/prevención & control , ARN Helicasas DEAD-box/metabolismo , Precondicionamiento Isquémico/métodos , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/prevención & control , Animales , Carboximetilcelulosa de Sodio/análogos & derivados , Carboximetilcelulosa de Sodio/metabolismo , Carboximetilcelulosa de Sodio/uso terapéutico , Helicasa Inducida por Interferón IFIH1 , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fármacos Neuroprotectores/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Poli I-C/metabolismo , Poli I-C/uso terapéutico , Polilisina/análogos & derivados , Polilisina/metabolismo , Polilisina/uso terapéutico
5.
Acta Neurochir Suppl ; 121: 39-44, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26463920

RESUMEN

Stroke activates an inflammatory response that results in the infiltration of peripheral immune cells into the ischemic area, contributing to exacerbation of tissue damage. However, evidence indicates that inflammatory cell infiltration can also promote neuroprotection through regulatory immune cells that mitigate injury. These immune regulatory cells may also be important mediators of neuroprotection associated with preconditioning, a phenomenon whereby small exposure to a potential harmful stimulus is able to induce protection against a subsequent ischemic event. The elucidation of mechanisms that allow these immune cells to confer neuroprotection is critical to developing new therapeutic strategies against acute stroke. In the present review, we discuss the dual role of peripheral immune cells in stroke-related brain injury and neuroprotection. Furthermore, we report new data from our laboratory that supports the important role of peripheral cells and their interaction with the brain endothelium for the establishment of the protective phenotype in preconditioning.


Asunto(s)
Precondicionamiento Isquémico , Linfocitos/inmunología , Macrófagos/inmunología , Neuroprotección/inmunología , Neutrófilos/inmunología , Accidente Cerebrovascular/inmunología , Animales , Humanos
6.
Analyst ; 139(14): 3528-32, 2014 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-24802717

RESUMEN

Matrix effects in mass spectrometry imaging (MSI) may affect the observed molecular distribution in chemical and biological systems. In this study, we use mouse brain tissue of a middle cerebral artery occlusion (MCAO) stroke model to examine matrix effects in nanospray desorption electrospray ionization MSI (nano-DESI MSI). This is achieved by normalizing the intensity of the sodium and potassium adducts of endogenous phosphatidylcholine (PC) species to the intensity of the corresponding adduct of the PC standard supplied at a constant rate with the nano-DESI solvent. The use of MCAO model with an ischemic region localized to one hemisphere of the brain enables immediate comparison of matrix effects within one ion image. Furthermore, significant differences in sodium and potassium concentrations in the ischemic region in comparison with the healthy tissue allowed us to distinguish between two types of matrix effects. Specifically, we discuss matrix effects originating from variations in alkali metal concentrations and matrix effects originating from variations in the molecular composition of the tissue. Compensation for both types of matrix effects was achieved by normalizing the signals corresponding to endogenous PC to the signals of the standards. This approach, which does not introduce any complexity in sample preparation, efficiently compensates for signal variations resulting from differences in the local concentrations of sodium and potassium in tissue sections and from the complexity of the extracted analyte mixture derived from local variations in molecular composition.


Asunto(s)
Química Encefálica , Encéfalo/irrigación sanguínea , Encéfalo/patología , Infarto de la Arteria Cerebral Media/patología , Espectrometría de Masa por Ionización de Electrospray/métodos , Animales , Infarto de la Arteria Cerebral Media/diagnóstico , Ratones , Ratones Endogámicos C57BL , Imagen Óptica/métodos , Fosfatidilcolinas/análisis , Potasio/análisis , Sodio/análisis
7.
BMJ Open ; 14(2): e077309, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388500

RESUMEN

OBJECTIVES: To identify, chart and analyse the literature on recent initiatives to improve long-term care (LTC) coverage, financial protection and financial sustainability for persons aged 60 and older. DESIGN: Rapid scoping review. DATA SOURCES: Four databases and four sources of grey literature were searched for reports published between 2017 and 2022. After using a supervised machine learning tool to rank titles and abstracts, two reviewers independently screened sources against inclusion criteria. ELIGIBILITY CRITERIA: Studies published from 2017-2022 in any language that captured recent LTC initiatives for people aged 60 and older, involved evaluation and directly addressed financing were included. DATA EXTRACTION AND ANALYSIS: Data were extracted using a form designed to answer the review questions and analysed using descriptive qualitative content analysis, with data categorised according to a prespecified framework to capture the outcomes of interest. RESULTS: Of 24 reports, 22 were published in peer-reviewed journals, and two were grey literature sources. Study designs included quasi-experimental study, policy analysis or comparison, qualitative description, comparative case study, cross-sectional study, systematic literature review, economic evaluation and survey. Studies addressed coverage based on the level of disability, income, rural/urban residence, employment and citizenship. Studies also addressed financial protection, including out-of-pocket (OOP) expenditures, copayments and risk of poverty related to costs of care. The reports addressed challenges to financial sustainability such as lack of service coordination and system integration, insufficient economic development and inadequate funding models. CONCLUSIONS: Initiatives where LTC insurance is mandatory and accompanied by commensurate funding are situated to facilitate ageing in place. Efforts to expand population coverage are common across the initiatives, with the potential for wider economic benefits. Initiatives that enable older people to access the services needed while avoiding OOP-induced poverty contribute to improved health and well-being. Preserving health in older people longer may alleviate downstream costs and contribute to financial sustainability.


Asunto(s)
Vida Independiente , Cuidados a Largo Plazo , Humanos , Anciano , Persona de Mediana Edad , Estudios Transversales , Gastos en Salud , Seguro de Cuidados a Largo Plazo
8.
PLoS Comput Biol ; 8(10): e1002722, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23071432

RESUMEN

The ability to examine the behavior of biological systems in silico has the potential to greatly accelerate the pace of discovery in diseases, such as stroke, where in vivo analysis is time intensive and costly. In this paper we describe an approach for in silico examination of responses of the blood transcriptome to neuroprotective agents and subsequent stroke through the development of dynamic models of the regulatory processes observed in the experimental gene expression data. First, we identified functional gene clusters from these data. Next, we derived ordinary differential equations (ODEs) from the data relating these functional clusters to each other in terms of their regulatory influence on one another. Dynamic models were developed by coupling these ODEs into a model that simulates the expression of regulated functional clusters. By changing the magnitude of gene expression in the initial input state it was possible to assess the behavior of the networks through time under varying conditions since the dynamic model only requires an initial starting state, and does not require measurement of regulatory influences at each time point in order to make accurate predictions. We discuss the implications of our models on neuroprotection in stroke, explore the limitations of the approach, and report that an optimized dynamic model can provide accurate predictions of overall system behavior under several different neuroprotective paradigms.


Asunto(s)
Redes Reguladoras de Genes , Modelos Genéticos , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/metabolismo , Transcriptoma , Algoritmos , Animales , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Simulación por Computador , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Ratones , Ratones Endogámicos C57BL , Familia de Multigenes , Reproducibilidad de los Resultados
9.
Can Geriatr J ; 26(3): 390-399, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37662062

RESUMEN

Background: Social vulnerability is the accumulation of disadvantageous social circumstances resulting in susceptibility to adverse health outcomes. Associated with increased mortality, cognitive decline, and disability, social vulnerability has primarily been studied in large population databases rather than frail hospitalized individuals. We examined how social vulnerability contributes to hospital outcomes and use of hospital resources for older adults presenting to the Emergency Department. Methods: We analyzed patients 65 years of age or older admitted through the Emergency Department and consulted to internal medicine or geriatrics at a Canadian tertiary care hospital from July 2009 to September 2020. A 20-item social vulnerability index (SVI) and a 57-item frailty index (FI) were calculated, using a deficit accumulation approach. Outcomes were length of stay (LOS), extended hospital LOS designation, alternative level of care (ALC) designation, in-hospital mortality, and discharge to long-term care (LTC). Results: In 1,146 patients (mean age 80.5±8.3, 54.0% female), mean SVI was 0.40±0.16 and FI was 0.44±0.14. The SVI scores were not associated with admission to hospital. Amongst those admitted, for every 0.1 unit increase in SVI, LOS increased by 1.15 days (p<.001) after adjusting for age, sex and FI. SVI was associated with staying over the expected LOS (aOR: 1.19, 1.05-1.34, p=.009) and ALC status (aOR 1.39, 1.12-1.74, p<.004). SVI was not associated with in-hospital mortality, but was associated with incident discharge to LTC (aOR 1.03, 1.02-1.04, p<.001). Conclusion: Independent of frailty, being socially vulnerable was associated with increased LOS, designation as ALC, and being discharged to LTC from hospital. Consideration of social vulnerability's influence on prolonged hospitalization and long-term care needs has implications for screening and hospital resources.

10.
J Subst Use Addict Treat ; 154: 209156, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37652208

RESUMEN

INTRODUCTION: Veterans are at greater risk for suicide and veterans with substance use disorder (SUD) have an even greater risk. Little research has looked into brief interventions to prevent suicide in this population in residential substance use treatment programs. METHOD: We conducted a pilot, randomized controlled trial of a brief suicide prevention strategy called Veterans Affairs Brief Intervention and Contact Program (VA BIC) in patients participating in the Residential Recovery Center (RRC) SUD 28-day program and deemed at risk for suicide. We measured changes in symptoms at 1-, 3-, and 6-months. We looked at social connectedness, suicidal ideation, hopelessness, thwarted belongingness, perceived burdensomeness, and treatment engagement. RESULTS: The study enrolled twenty patients. One participant withdrew immediately after baseline. We found that adherence to VA BIC components was high, as 100 % of patients (N = 10) completed 70 % or more of the VA BIC visits. Furthermore, 80 % of intervention group patients (N = 8) completed all VA BIC components. During the six-month follow-up, suicidal ideation improved in patients assigned to VA BIC, while it worsened in the standard care arm. Similarly, patients assigned to VA BIC reported a reduction in perceived burdensomeness over the six-month follow-up period while it worsened in the standard care arm. Additionally, VA BIC may modestly improve treatment engagement in the first month postdischarge. CONCLUSION: We were able to recruit and enroll patients from a residential SUD treatment program into a clinical trial of the VA BIC intervention. Our preliminary results suggest that VA BIC may be useful in reducing suicidal ideation and perceived burdensomeness in patients who are discharged from residential SUD treatment programs and increasing treatment engagement. Future trials of VA BIC should determine whether VA BIC can reduce the risk of suicide in patients who are discharged from residential SUD treatment programs.

11.
J Neurosci ; 31(23): 8456-63, 2011 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-21653850

RESUMEN

Ischemic tolerance can be induced by numerous preconditioning stimuli, including various Toll-like receptor (TLR) ligands. We have shown previously that systemic administration of the TLR4 ligand LPS or the TLR9 ligand unmethylated CpG oligodeoxynucleotide before transient brain ischemia in mice confers substantial protection against ischemic damage. To elucidate the molecular mechanisms of preconditioning, we compared brain genomic profiles in response to preconditioning with these TLR ligands and with preconditioning via exposure to brief ischemia. We found that exposure to the TLR ligands and brief ischemia induced genomic changes in the brain characteristic of a TLR pathway-mediated response. Interestingly, all three preconditioning stimuli resulted in a reprogrammed response to stroke injury that converged on a shared subset of 13 genes not evident in the genomic profile from brains that were subjected to stroke without prior preconditioning. Analysis of the promoter region of these shared genes showed sequences required for interferon regulatory factor (IRF)-mediated transcription. The importance of this IRF gene network was tested using mice deficient in IRF3 or IRF7. Our data show that both transcription factors are required for TLR-mediated preconditioning and neuroprotection. These studies are the first to discover a convergent mechanism of neuroprotection induced by preconditioning--one that potentially results in reprogramming of the TLR-mediated response to stroke and requires the presence of IRF3 and IRF7.


Asunto(s)
Isquemia Encefálica/inmunología , Encéfalo/inmunología , Factores Reguladores del Interferón/inmunología , Precondicionamiento Isquémico/métodos , Lipopolisacáridos/farmacología , Receptores Toll-Like/inmunología , Animales , Encéfalo/irrigación sanguínea , Encéfalo/efectos de los fármacos , Isquemia Encefálica/genética , Expresión Génica/efectos de los fármacos , Factores Reguladores del Interferón/genética , Lipopolisacáridos/inmunología , Masculino , Ratones , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Receptores Toll-Like/genética
12.
Stroke ; 43(5): 1383-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22403050

RESUMEN

BACKGROUND AND PURPOSE: Systemic administration of Toll-like receptor (TLR) 4 and TLR9 agonists before cerebral ischemia have been shown to reduce ischemic injury by reprogramming the response of the brain to stroke. Our goal was to explore the mechanism of TLR-induced neuroprotection by determining whether a TLR7 agonist also protects against stroke injury. METHODS: C57Bl/6, TNF(-/-), interferon (IFN) regulatory factor 7(-/-), or type I IFN receptor (IFNAR)(-/-) mice were subcutaneously administered the TLR7 agonist Gardiquimod (GDQ) 72 hours before middle cerebral artery occlusion. Infarct volume and functional outcome were determined after reperfusion. Plasma cytokine responses and induction of mRNA for IFN-related genes in the brain were measured. IFNAR(-/-) mice also were treated with the TLR4 agonist (lipopolysaccharide) or the TLR9 agonist before middle cerebral artery occlusion and infarct volumes measured. RESULTS: The results show that GDQ reduces infarct volume as well as functional deficits in mice. GDQ pretreatment provided robust neuroprotection in TNF(-/-) mice, indicating that TNF was not essential. GDQ induced a significant increase in plasma IFNα levels and both IRF7(-/-) and IFNAR(-/-) mice failed to be protected, implicating a role for IFN signaling in TLR7-mediated protection. CONCLUSIONS: Our studies provide the first evidence that TLR7 preconditioning can mediate neuroprotection against ischemic injury. Moreover, we show that the mechanism of protection is unique from other TLR preconditioning ligands in that it is independent of TNF and dependent on IFNAR.


Asunto(s)
Aminoquinolinas/uso terapéutico , Encéfalo/irrigación sanguínea , Imidazoles/uso terapéutico , Precondicionamiento Isquémico/métodos , Glicoproteínas de Membrana/agonistas , Fármacos Neuroprotectores/uso terapéutico , Receptor de Interferón alfa y beta/fisiología , Accidente Cerebrovascular/prevención & control , Receptor Toll-Like 7/agonistas , Animales , Infarto Encefálico/patología , Factor 7 Regulador del Interferón/deficiencia , Factor 7 Regulador del Interferón/genética , Factor 7 Regulador del Interferón/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Animales , Receptor de Interferón alfa y beta/deficiencia , Receptor de Interferón alfa y beta/genética , Transducción de Señal/fisiología , Accidente Cerebrovascular/fisiopatología , Factor de Necrosis Tumoral alfa/deficiencia , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/fisiología
13.
J Neurochem ; 123 Suppl 2: 75-85, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23050645

RESUMEN

Preconditioning with a low dose of harmful stimulus prior to injury induces tolerance to a subsequent ischemic challenge resulting in neuroprotection against stroke. Experimental models of preconditioning primarily focus on neurons as the cellular target of cerebral protection, while less attention has been paid to the cerebrovascular compartment, whose role in the pathogenesis of ischemic brain injury is crucial. We have shown that preconditioning with polyinosinic polycytidylic acid (poly-ICLC) protects against cerebral ischemic damage. To delineate the mechanism of poly-ICLC protection, we investigated whether poly-ICLC preconditioning preserves the function of the blood-brain barrier (BBB) in response to ischemic injury. Using an in vitro BBB model, we found that poly-ICLC treatment prior to exposure to oxygen-glucose deprivation maintained the paracellular and transcellular transport across the endothelium and attenuated the drop in transendothelial electric resistance. We found that poly-ICLC treatment induced interferon (IFN) ß mRNA expression in astrocytes and microglia and that type I IFN signaling in brain microvascular endothelial cells was required for protection. Importantly, this implicates a potential mechanism underlying neuroprotection in our in vivo experimental stroke model, where type I IFN signaling is required for poly-ICLC-induced neuroprotection against ischemic injury. In conclusion, we are the first to show that preconditioning with poly-ICLC attenuates ischemia-induced BBB dysfunction. This mechanism is likely an important feature of poly-ICLC-mediated neuroprotection and highlights the therapeutic potential of targeting BBB signaling pathways to protect the brain against stroke.


Asunto(s)
Barrera Hematoencefálica/efectos de los fármacos , Carboximetilcelulosa de Sodio/análogos & derivados , Infarto de la Arteria Cerebral Media/prevención & control , Factor 1 Regulador del Interferón/metabolismo , Precondicionamiento Isquémico/métodos , Fármacos Neuroprotectores/administración & dosificación , Poli I-C/administración & dosificación , Polilisina/análogos & derivados , Transducción de Señal/efectos de los fármacos , Análisis de Varianza , Animales , Animales Recién Nacidos , Barrera Hematoencefálica/metabolismo , Infarto Encefálico/tratamiento farmacológico , Infarto Encefálico/etiología , Carboximetilcelulosa de Sodio/administración & dosificación , Carboximetilcelulosa de Sodio/farmacología , Células Cultivadas , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática/métodos , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Glucosa/deficiencia , Hipoxia/tratamiento farmacológico , Hipoxia/metabolismo , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/genética , Factor 1 Regulador del Interferón/deficiencia , Interferón beta/genética , Interferón beta/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuroglía/efectos de los fármacos , Poli I-C/farmacología , Polilisina/administración & dosificación , Polilisina/farmacología , ARN Mensajero/metabolismo , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/patología , Factores de Tiempo
14.
Clin Interv Aging ; 17: 447-465, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35431543

RESUMEN

Background: Social vulnerability occurs when individuals have been relatively disadvantaged by the social determinants of health. Complex interventions that reduce social vulnerability have the potential to improve health in older adults but robust evidence is lacking. Objective: To identify, appraise and synthesize evidence on the effectiveness of complex interventions targeting reduction in social vulnerability for improving health related outcomes (mortality, function, cognition, subjective health and healthcare use) in older adults living in the community. Methods: A mixed methods systematic review was conducted. Five databases and targeted grey literature were searched for primary studies of all study types according to predetermined criteria. Data were extracted from each distinct intervention and quality was assessed using the Mixed Methods Appraisal Tool. Effectiveness data were synthesized using vote counting by direction of effect, combining p values and Albatross plots. Results: Across 38 included studies, there were 34 distinct interventions categorized as strengthening social supports and communities, helping older adults and their caregivers navigate health and social services, enhancing neighbourhood and built environments, promoting education and providing economic stability. There was evidence to support positive influences on function, cognition, subjective health, and reduced hospital utilization. The evidence was mixed for non-hospital healthcare utilization and insufficient to determine effect on mortality. Conclusion: Despite high heterogeneity and varying quality of studies, attention to reducing an older adult's social vulnerability assists in improving older adults' health.


Asunto(s)
Vida Independiente , Vulnerabilidad Social , Anciano , Cuidadores , Escolaridad , Humanos , Apoyo Social
15.
Can J Nurs Res ; 54(4): 483-496, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34704507

RESUMEN

BACKGROUND: An increasing proportion of older adults experience avoidable hospitalizations, and some are potentially entering long-term care homes earlier and often unnecessarily. Older adults often lack adequate support to transition from hospital to home, without access to appropriate health services when they are needed in the community and resources to live safely at home. PURPOSE: This study collaborated with an existing enhanced home care program called Home Again in Nova Scotia, to identify factors that contribute to older adult patients being assessed as requiring long-term care when they could potentially return home with enhanced supports. METHODS: Using a case study design, this study examined in-depth experiences of multiple stakeholders, from December 2019 to February 2020, through analysis of nine interviews for three focal patient cases including older adult patients, their family or friend caregivers, and healthcare professionals. RESULTS: Findings indicate home care services for older adults are being sought too late, after hospital readmission, or a rapid decline in health status when family caregivers are already experiencing caregiver burnout. Limitations in home care services led to barriers preventing family caregivers from continuing to care for older adults at home. CONCLUSIONS: This study contributes knowledge about gaps within home care and transitional care services, highlighting the importance of investing in additional home care services for rehabilitation and prevention of rapidly deteriorating health.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Transición del Hospital al Hogar , Humanos , Anciano , Cuidadores , Hospitales , Cuidados a Largo Plazo
16.
ACS Chem Biol ; 17(5): 1073-1081, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35471821

RESUMEN

We sought to develop a small-molecule activator of interferon regulatory factor 3 (IRF3), an essential innate immune transcription factor, which could potentially be used therapeutically in multiple disease settings. Using a high-throughput screen, we identified small-molecule entities that activate a type I interferon response, with minimal off-target NFκB activation. We identified 399 compounds at a hit rate of 0.24% from singlicate primary screening. Secondary screening included the primary hits and additional compounds with similar chemical structures obtained from other library sources and resulted in 142 candidate compounds. The hit compounds were sorted and ranked to identify compound groups with activity in both human and mouse backgrounds to facilitate animal model engagement for translational development. Chemical modifications within two groups of small molecules produced leads with improved activity over original hits. Furthermore, these leads demonstrated activity in ex vivo cytokine release assays from human blood- and mouse bone marrow-derived macrophages. Dependence on IRF3 was demonstrated using bone marrow-derived macrophages from IRF3-deficient mice, which were not responsive to the molecules. To identify the upstream pathway leading to IRF3 activation, we used a library of CRISPR knockout cell lines to test the key innate immune adaptor and receptor molecules. These studies indicated a surprising toll-interleukin-1 receptor-domain-containing-adapter-inducing interferon-ß-dependent but TLR3/4-independent mechanism of IRF3 activation.


Asunto(s)
Factor 3 Regulador del Interferón , Transducción de Señal , Animales , Antivirales/farmacología , Desarrollo de Medicamentos , Factor 3 Regulador del Interferón/metabolismo , Macrófagos/metabolismo , Ratones
17.
Jt Comm J Qual Patient Saf ; 48(10): 503-512, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35382976

RESUMEN

BACKGROUND: Suicide after psychiatric hospitalization is a major concern. Poor treatment engagement may contribute to risk. The World Health Organization Brief Intervention and Contact (BIC) Program is an evidence-based practice shown to prevent suicide after psychiatric discharge in international trials. There have been no efforts to implement BIC into routine practice in US populations. METHODS: The authors conducted a 12-month quality improvement (QI) collaborative at six US Department of Veterans Affairs (VA) medical centers serving a large rural population. Sites had low to moderate performance on a VA quality measure of mental health postdischarge care; a measure assessing the proportion of discharged patients who achieve the required number of visits ≤ 30 days. Sites received programmatic support to implement BIC locally. Implementation was assessed using the Reach, Effectiveness, Adoption, Implementation, Maintenance (RE-AIM) framework. RESULTS: Overall, teams had high participation in programmatic activities and enrolled 85% of eligible patients that they approached. Among 70 enrolled patients, 81.4% achieved the VA quality measure of mental health postdischarge care, suggesting good treatment engagement. On average, patients rated BIC as excellent. Team members agreed that BIC was easy to use, implementable, possible, and doable. Factors facilitating implementation included standardized operating procedures to standardize processes. Barriers included insufficient staffing and loss to follow-up. Most sites plan to continue to enroll patients and to expand BIC to other areas. CONCLUSION: A QI collaborative can facilitate implementation of BIC in six VA facilities that provide inpatient psychiatric treatment. BIC may appeal to patients and providers and may improve treatment engagement.


Asunto(s)
Prevención del Suicidio , Veteranos , Cuidados Posteriores , Humanos , Alta del Paciente , Atención Primaria de Salud , Mejoramiento de la Calidad , Estados Unidos , United States Department of Veterans Affairs
18.
Gen Hosp Psychiatry ; 75: 68-74, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35202942

RESUMEN

OBJECTIVE: Patients who die by suicide are often seen in primary care settings in the weeks leading to their death. There has been little study of brief interventions to prevent suicide in these settings. METHOD: We conducted a virtual, pilot, randomized controlled trial of a brief suicide prevention strategy called Veterans Affairs Brief Intervention and Contact Program (VA BIC) in patients who presented to a primary care mental health walk-in clinic for a new mental health intake appointment and were at risk for suicide. Our primary aim was to assess feasibility. We measured our ability to recruit 20 patients. We measured the proportion of enrolled patients who completed all study assessments. We assessed adherence among patients assigned to VA BIC. RESULTS: Twenty patients were enrolled and 95% (N = 19) completed all study assessments. Among the 10 patients assigned to VA BIC, 90% (N = 9) of patients completed all required intervention visits, and 100% (N = 10) completed ≥70% of the required interventions visits. CONCLUSION: It is feasible to conduct a virtual trial of VA BIC in an integrated care setting. Future research should clarify the role of VA BIC as a suicide prevention strategy in integrated care settings using an adequately powered design. CLINICAL TRIAL REGISTRATION: NCT04054947.


Asunto(s)
Prestación Integrada de Atención de Salud , Prevención del Suicidio , Intervención en la Crisis (Psiquiatría) , Humanos , Salud Mental , Proyectos Piloto
19.
PLoS One ; 17(4): e0266569, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35390091

RESUMEN

BACKGROUND: Individuals receiving palliative care (PC) are generally thought to prefer to receive care and die in their homes, yet little research has assessed the quality of home- and community-based PC. This project developed a set of valid and reliable quality indicators (QIs) that can be generated using data that are already gathered with interRAI assessments-an internationally validated set of tools commonly used in North America for home care clients. The QIs can serve as decision-support measures to assist providers and decision makers in delivering optimal care to individuals and their families. METHODS: The development efforts took part in multiple stages, between 2017-2021, including a workshop with clinicians and decision-makers working in PC, qualitative interviews with individuals receiving PC, families and decision makers and a modified Delphi panel, based on the RAND/ULCA appropriateness method. RESULTS: Based on the workshop results, and qualitative interviews, a set of 27 candidate QIs were defined. They capture issues such as caregiver burden, pain, breathlessness, falls, constipation, nausea/vomiting and loneliness. These QIs were further evaluated by clinicians/decision makers working in PC, through the modified Delphi panel, and five were removed from further consideration, resulting in 22 QIs. CONCLUSIONS: Through in-depth and multiple-stakeholder consultations we developed a set of QIs generated with data already collected with interRAI assessments. These indicators provide a feasible basis for quality benchmarking and improvement systems for care providers aiming to optimize PC to individuals and their families.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Cuidados Paliativos , Técnica Delphi , Humanos , América del Norte , Indicadores de Calidad de la Atención de Salud
20.
J Neuroinflammation ; 8: 140, 2011 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-21999375

RESUMEN

BACKGROUND: Toll-like receptor 4 (TLR4) is activated in response to cerebral ischemia leading to substantial brain damage. In contrast, mild activation of TLR4 by preconditioning with low dose exposure to lipopolysaccharide (LPS) prior to cerebral ischemia dramatically improves outcome by reprogramming the signaling response to injury. This suggests that TLR4 signaling can be altered to induce an endogenously neuroprotective phenotype. However, the TLR4 signaling events involved in this neuroprotective response are poorly understood. Here we define several molecular mediators of the primary signaling cascades induced by LPS preconditioning that give rise to the reprogrammed response to cerebral ischemia and confer the neuroprotective phenotype. METHODS: C57BL6 mice were preconditioned with low dose LPS prior to transient middle cerebral artery occlusion (MCAO). Cortical tissue and blood were collected following MCAO. Microarray and qtPCR were performed to analyze gene expression associated with TLR4 signaling. EMSA and DNA binding ELISA were used to evaluate NFκB and IRF3 activity. Protein expression was determined using Western blot or ELISA. MyD88-/- and TRIF-/- mice were utilized to evaluate signaling in LPS preconditioning-induced neuroprotection. RESULTS: Gene expression analyses revealed that LPS preconditioning resulted in a marked upregulation of anti-inflammatory/type I IFN-associated genes following ischemia while pro-inflammatory genes induced following ischemia were present but not differentially modulated by LPS. Interestingly, although expression of pro-inflammatory genes was observed, there was decreased activity of NFκB p65 and increased presence of NFκB inhibitors, including Ship1, Tollip, and p105, in LPS-preconditioned mice following stroke. In contrast, IRF3 activity was enhanced in LPS-preconditioned mice following stroke. TRIF and MyD88 deficient mice revealed that neuroprotection induced by LPS depends on TLR4 signaling via TRIF, which activates IRF3, but does not depend on MyD88 signaling. CONCLUSION: Our results characterize several critical mediators of the TLR4 signaling events associated with neuroprotection. LPS preconditioning redirects TLR4 signaling in response to stroke through suppression of NFκB activity, enhanced IRF3 activity, and increased anti-inflammatory/type I IFN gene expression. Interestingly, this protective phenotype does not require the suppression of pro-inflammatory mediators. Furthermore, our results highlight a critical role for TRIF-IRF3 signaling as the governing mechanism in the neuroprotective response to stroke.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/inmunología , Isquemia Encefálica , Factor 3 Regulador del Interferón/inmunología , Precondicionamiento Isquémico , Lipopolisacáridos/farmacología , Transducción de Señal , Accidente Cerebrovascular , Receptor Toll-Like 4/inmunología , Proteínas Adaptadoras del Transporte Vesicular/genética , Animales , Isquemia Encefálica/sangre , Isquemia Encefálica/inmunología , Isquemia Encefálica/patología , Quimiocinas/sangre , Quimiocinas/inmunología , Citocinas/sangre , Citocinas/inmunología , Perfilación de la Expresión Génica , Humanos , Infarto de la Arteria Cerebral Media , Factor 3 Regulador del Interferón/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Análisis por Micromatrices , FN-kappa B/inmunología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/inmunología , Accidente Cerebrovascular/patología
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