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1.
Neurobiol Dis ; 166: 105652, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35143966

RESUMEN

Huntington disease (HD) is a neurodegenerative disease caused by a trinucleotide repeat expansion in the HTT gene encoding an elongated polyglutamine tract in the huntingtin (HTT) protein. Expanded mutant HTT (mHTT) is toxic and leads to regional atrophy and neuronal cell loss in the brain, which occurs earliest in the striatum. Therapeutic lowering of mHTT in the central nervous system (CNS) has shown promise in preclinical studies, with multiple approaches currently in clinical development for HD. Quantitation of mHTT in the cerebrospinal fluid (CSF) is being used as a clinical pharmacodynamic biomarker of target engagement in the CNS. We have previously shown that the CNS is a major source of mHTT in the CSF. However, little is known about the specific brain regions and cell types that contribute to CSF mHTT. Therefore, a better understanding of the origins of CSF mHTT and whether therapies targeting mHTT in the striatum would be expected to be associated with significant lowering of mHTT in the CSF is needed. Here, we use complementary pharmacological and genetic-based approaches to either restrict expression of mHTT to the striatum or selectively deplete mHTT in the striatum to evaluate the contribution of this brain region to mHTT in the CSF. We show that viral expression of a mHTT fragment restricted to the striatum leads to detectable mHTT in the CSF. We demonstrate that targeted lowering of mHTT selectively in the striatum using an antisense oligonucleotide leads to a significant reduction of mHTT in the CSF of HD mice. Furthermore, using a transgenic mouse model of HD that expresses full length human mHTT and wild type HTT, we show that genetic inactivation of mHTT selectively in the striatum results in a significant reduction of mHTT in the CSF. Taken together, our data supports the conclusion that the striatum contributes sufficiently to the pool of mHTT in the CSF that therapeutic levels of mHTT lowering in the striatum can be detected by this measure in HD mice. This suggests that CSF mHTT may represent a pharmacodynamic biomarker for therapies that lower mHTT in the striatum.


Asunto(s)
Enfermedad de Huntington , Enfermedades Neurodegenerativas , Animales , Biomarcadores/líquido cefalorraquídeo , Modelos Animales de Enfermedad , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Enfermedad de Huntington/metabolismo , Ratones , Ratones Transgénicos , Enfermedades Neurodegenerativas/genética , Expansión de Repetición de Trinucleótido/genética
2.
Conserv Biol ; 35(6): 1725-1737, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33738830

RESUMEN

Calls for biodiversity conservation practice to be more evidence based are growing, and we agree evidence use in conservation practice needs improvement. However, evidence-based conservation will not be realized without improved access to evidence. In medicine, unlike in conservation, a well-established and well-funded layer of intermediary individuals and organizations engage with medical practitioners, synthesize primary research relevant to decision making, and make evidence easily accessible. These intermediaries prepare targeted evidence summaries and distribute them to practitioners faced with time-sensitive and value-laden decisions. To be effective, these intermediaries, who we refer to as evidence bridges, should identify research topics based on the priorities of practitioners; synthesize evidence; prepare and distribute easy-to-find and easy-to-use evidence summaries; and develop and maintain networks of connections with researchers and practitioners. Based on a review of the literature regarding evidence intermediaries in conservation and environmental management, as well as an anonymous questionnaire searching for such organizations, we found few intermediaries that met all these criteria. Few evidence bridges that do exist are unable to reach most conservation practitioners, which include resource managers in government and industry, conservation organizations, and farmers and other private landowners. We argue that the lack of evidence bridges from research to practitioners contributes to evidence complacency and limits the use of evidence in conservation action. Nevertheless, several existing organizations help reduce the gap between evidence and practice and could serve as a foundation for building additional components of evidence bridges in conservation. Although evidence bridges need expertise in research and evidence synthesis, they also require expertise in identifying and communicating with the community of practitioners most in need of clear and concise syntheses of evidence. Article Impact Statement: Evidence-based conservation will not be realized without improved access to evidence. We call for intermediary evidence bridges.


Vinculación entre la Investigación y la Práctica en la Conservación Resumen Cada vez existen más peticiones para que las prácticas de conservación de la biodiversidad estén más basadas en evidencias, además de que apoyamos la idea de que el uso de evidencias en la práctica de la conservación necesita mejorar. Sin embargo, la conservación basada en la evidencia no se logrará sin un acceso mejorado a las evidencias. En la medicina, no como en la conservación, un estrato bien establecido y financiado de individuos y organizaciones intermediarias interactúan con los médicos, sintetizan las investigaciones primarias relevantes para la toma de decisiones y hacen que las evidencias sean de fácil acceso. Estos intermediarios preparan resúmenes de evidencias específicas y los distribuyen a los médicos que enfrentan decisiones urgentes y muy valiosas. Para que sean efectivos, estos intermediarios, a quienes nos referimos como puentes de evidencias, deben poder identificar los temas de estudio con base en las prioridades de los practicantes, sintetizar evidencias, preparar y distribuir resúmenes fáciles de encontrar y fáciles de usar, y desarrollar y mantener redes de conexiones con los investigadores y los practicantes. Con base en una revisión de la literatura correspondiente a los intermediarios de evidencias en la conservación y el manejo ambiental, así como en un cuestionario anónimo que busca a dichas organizaciones, encontramos a pocos intermediarios que cumplieran con estos criterios. Los pocos puentes de evidencias que existen no son capaces de llegar a la mayoría de los practicantes de la conservación, los cuales incluyen a los gestores de recursos en el gobierno y en la industria, a las organizaciones de conservación y a los agricultores y otros terratenientes privados. Argumentamos que la falta de puentes de evidencia entre los investigadores y los practicantes contribuye a la indulgencia de evidencias y limita el uso de evidencias en las acciones de conservación. Sin embargo, varias organizaciones existentes ayudan a reducir la brecha entre la evidencia y la práctica y podrían funcionar como base para la construcción de componentes adicionales para los puentes de evidencia en la conservación. Aunque los puentes de evidencias necesitan experiencia con la investigación y con la síntesis de evidencias, también requieren experiencia con la identificación de y comunicación con la comunidad de practicantes que más necesitan una síntesis clara y concisa de la evidencia.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Humanos , Organizaciones , Investigadores
3.
BMC Med Inform Decis Mak ; 21(1): 253, 2021 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-34461876

RESUMEN

BACKGROUND: Hospital-acquired pressure injuries (PIs) induce significant patient suffering, inflate healthcare costs, and increase clinical co-morbidities. PIs are mostly due to bed-immobility, sensory impairment, bed positioning, and length of hospital stay. In this study, we use electronic health records and administrative data to examine the contributing factors to PI development using artificial intelligence (AI). METHODS: We used advanced data science techniques to first preprocess the data and then train machine learning classifiers to predict the probability of developing PIs. The AI training was based on large, incongruent, incomplete, heterogeneous, and time-varying data of hospitalized patients. Both model-based statistical methods and model-free AI strategies were used to forecast PI outcomes and determine the salient features that are highly predictive of the outcomes. RESULTS: Our findings reveal that PI prediction by model-free techniques outperform model-based forecasts. The performance of all AI methods is improved by rebalancing the training data and by including the Braden in the model learning phase. Compared to neural networks and linear modeling, with and without rebalancing or using Braden scores, Random forest consistently generated the optimal PI forecasts. CONCLUSIONS: AI techniques show promise to automatically identify patients at risk for hospital acquired PIs in different surgical services. Our PI prediction model provide a first generation of AI guidance to prescreen patients at risk for developing PIs. CLINICAL IMPACT: This study provides a foundation for designing, implementing, and assessing novel interventions addressing specific healthcare needs. Specifically, this approach allows examining the impact of various dynamic, personalized, and clinical-environment effects on PI prevention for hospital patients receiving care from various surgical services.


Asunto(s)
Inteligencia Artificial , Aprendizaje Automático , Úlcera por Presión , Humanos , Registros Electrónicos de Salud , Pacientes Internos , Redes Neurales de la Computación
4.
J Pediatr Nurs ; 58: 39-43, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33310550

RESUMEN

The objective of this quality initiative was to evaluate the process of implementing a new protocol using the Iowa model and evidence-base interventions. The first aim included deploying a protocol guiding sedation with dexmedetomidine for up to 24 h; the procedure involved non-intubated pediatric patients in the pediatric intensive care unit (PICU) while monitored by certified registered nurses. Dexmedetomidine is supported within the literature to be a safe and effective medication for pediatric patients, exceeding 24 h, without the adverse event of respiratory depression. The second aim was to then evaluate the implementation process. A pre-post educational approach was used, over a five-month period. Thirty-two nurses were educated and surveyed on their knowledge and attitudes regarding the use and administration of dexmedetomidine. The evaluation of pre and post knowledge surrounding dexmedetomidine was concluded following the post-survey. The evaluation of pre-post education showed, greater than 90% of the attending nurses, had an increase in their knowledge and understanding of safe use and monitoring for dexmedetomidine sedations in children. This quality initiative further supports effective application of evidence-based interventions. Moreover, using the Iowa model allowed for the effective execution in driving change, promoting sustainability, and improving safety in the delivery of care for pediatric patients receiving dexmedetomidine for long-term sedation.


Asunto(s)
Anestesia , Dexmedetomidina , Niño , Sedación Consciente , Humanos , Hipnóticos y Sedantes , Unidades de Cuidado Intensivo Pediátrico
5.
J Clin Nurs ; 29(7-8): 1398-1421, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31889342

RESUMEN

BACKGROUND: Despite decades of research, pressure injuries continue to be a source of significant pain and delayed recovery for patients and substantial quality and cost issues for hospitals. Consideration of the current thinking around pressure injury risk must be evaluated to improve risk assessments and subsequent nursing interventions aimed at reducing hospital-acquired pressure injuries. DESIGN: This is a discursive paper using Walker and Avant's (2005) theory synthesis framework to examine the relevance of existing pressure injury models as they align with the current literature. METHODS: PubMed and CINAHL indexes were searched, first for conceptual models and then for pressure injury research conducted on hospitalised patients for the years 2006-2016. A synthesis of the searches culminated into a new pressure injury risk model. CONCLUSIONS: Gaps in previous models include lack of attention to the environment, contributing episode-of-care factors and the dynamic nature of injury risk for patients. Through theory synthesis, the need for a new model representing the full risk for pressure injury was identified. The Pressure Injury Predictive Model is a representation of the complex and dynamic nature of pressure injury risk that builds on previous models and addresses new patient, contextual and episode-of-care process influences. The Pressure Injury Predictive Model (PIPM) provides a more accurate picture of the complexity of contextual and process factors associated with pressure injury development. RELEVANCE TO CLINICAL PRACTICE: Using the PIPM to determine risk can result in improved risk identification. This information can be used to implement targeted, evidence-based pressure injury prevention interventions specific to the patient risk profile, thus limiting unwarranted and unnecessary care.


Asunto(s)
Teoría de Enfermería , Úlcera por Presión/prevención & control , Medición de Riesgo/métodos , Enfermería Basada en la Evidencia , Hospitalización , Humanos , Úlcera por Presión/enfermería
6.
Hum Genomics ; 12(1): 16, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29587854

RESUMEN

MicroRNAs (miRNAs) are crucial regulators of gene expression in normal development and cellular homeostasis. While miRNA repositories contain thousands of unique sequences, they primarily contain molecules that are conserved across several tissues, largely excluding lineage and tissue-specific miRNAs. By analyzing small non-coding RNA sequencing data for abundance and secondary RNA structure, we discovered 103 miRNA candidates previously undescribed in liver tissue. While expression of some of these unannotated sequences is restricted to non-malignant tissue, downregulation of most of the sequences was detected in liver tumors, indicating their importance in the maintenance of liver homeostasis. Furthermore, target prediction revealed the involvement of the unannotated miRNA candidates in fatty-acid metabolism and tissue regeneration, which are key pathways in liver biology. Here, we provide a comprehensive analysis of the undiscovered liver miRNA transcriptome, providing new resources for a deeper exploration of organ-specific biology and disease.


Asunto(s)
Hígado/metabolismo , MicroARNs/genética , Transcriptoma/genética , Secuencia Conservada/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , MicroARNs/metabolismo , Especificidad de Órganos , Análisis de Secuencia de ARN
7.
Nucleic Acids Res ; 45(7): 4094-4107, 2017 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-27956496

RESUMEN

Dual-assignment of codons as termination and elongation codons is used to expand the genetic code. In mammals, UGA can be reassigned to selenocysteine during translation of selenoproteins by a mechanism involving a 3΄ untranslated region (UTR) selenocysteine insertion sequence (SECIS) and the SECIS-binding protein Secisbp2. Here, we present data from ribosome profiling, RNA-Seq and mRNA half-life measurements that support distinct roles for Secisbp2 in UGA-redefinition and mRNA stability. Conditional deletions of the Secisbp2 and Trsp (tRNASec) genes in mouse liver were compared to determine if the effects of Secisbp2 loss on selenoprotein synthesis could be attributed entirely to the inability to incorporate Sec. As expected, tRNASec depletion resulted in loss of ribosome density downstream of all UGA-Sec codons. In contrast, the absence of Secisbp2 resulted in variable effects on ribosome density downstream of UGA-Sec codons that demonstrate gene-specific differences in Sec incorporation. For several selenoproteins in which loss of Secisbp2 resulted in greatly diminished mRNA levels, translational activity and Sec incorporation efficiency were shown to be unaffected on the remaining RNA. Collectively, these results demonstrate that Secisbp2 is not strictly required for Sec incorporation and has a distinct role in stabilizing mRNAs that can be separated from its effects on UGA-redefinition.


Asunto(s)
Codón de Terminación , Estabilidad del ARN , ARN Mensajero/metabolismo , ARN de Transferencia Aminoácido-Específico/genética , Proteínas de Unión al ARN/fisiología , Selenoproteínas/genética , Animales , Células Cultivadas , Hepatocitos/metabolismo , Masculino , Metilación , Ratones , Ratones Noqueados , Iniciación de la Cadena Peptídica Traduccional , Biosíntesis de Proteínas , ARN de Transferencia Aminoácido-Específico/metabolismo , Proteínas de Unión al ARN/genética , Ribosomas/metabolismo , Selenoproteínas/biosíntesis
8.
J Gerontol Nurs ; 45(1): 23-30, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30653234

RESUMEN

Falls are common adverse events following hospital discharge. However, prevention programs are not tailored for older patients transitioning home. To inform development of transitional fall prevention programs, nine older adults designated as being at risk of falls during hospitalization who were recently discharged home were asked about their perceptions of fall risk and prevention, as well as their knowledge and opinion of materials from the Centers for Disease Control and Prevention Stopping Elderly Accidents, Deaths & Injuries Initiative. Using the constant comparative method, five themes were identified: Sedentary Behaviors and Limited Functioning; Prioritization of Social Involvement; Low Perceived Fall Risk and Attribution of Risk to External Factors; Avoidance and Caution as Fall Prevention; and Limited Falls Prevention Information During Transition from Hospital to Home. Limited awareness of and engagement in effective fall prevention may heighten recently discharged older adults' risks for falls. Prevention programs tailored to the post-discharge period may engage patients in fall prevention, promote well-being and independence, and link hospital and community efforts. [Journal of Gerontological Nursing, 45(1), 23-30.].


Asunto(s)
Prevención de Accidentes/normas , Accidentes por Caídas/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Pacientes/psicología , Anciano , Anciano de 80 o más Años , Femenino , Servicios de Atención de Salud a Domicilio , Hospitalización , Humanos , Masculino , Michigan , Percepción , Factores de Riesgo
9.
J Infect Dis ; 213(3): 403-6, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26243315

RESUMEN

We examined serum samples from adults ages 48-64 who received multiple seasonal influenza vaccines from 2004 to 2009 for cross-neutralizing antibodies to potential pandemic strains. Using pseudoviruses bearing various hemagglutinins (HA-pseudoviruses), we found serum neutralization titers (≥160) in 100% against A/Japan/305/1957 (H2N2), 53% against A/Hong Kong/1073/99 (H9N2), 56% against the H3N2 variant A/Indiana/08/11 (H3N2v), 11% against A/Hong Kong/G9/97 (H9N2), and 36% A/chicken/Hong Kong/SF4/01 (H6N1). None had titers >160 to A/Shanghai/2/13 (H7N9) or A/Netherlands/219/03 (H7N7). Thirty-six percent to 0% had neutralization titers to various H5N1 strains. Titers to H9, H6, and H5 HA-pseudoviruses correlated with each other, but not with H3N2v, suggesting group-specific cross-neutralization.


Asunto(s)
Anticuerpos Antivirales/sangre , Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Gripe Humana/virología , Humanos , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/sangre , Persona de Mediana Edad , Pandemias
10.
Mol Cancer ; 15: 5, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26768585

RESUMEN

PIWI-interacting RNAs (piRNAs) are emerging players in cancer genomics. Originally described in the germline, there are over 20,000 piRNA genes in the human genome. In contrast to microRNAs, piRNAs interact with PIWI proteins, another member of the Argonaute family, and function primarily in the nucleus. There, they are involved in the epigenetic silencing of transposable elements in addition to the transcriptional regulation of genes. It has recently been demonstrated that piRNAs are also expressed across a variety of human somatic tissue types in a tissue-specific manner. An increasing number of studies have shown that aberrant piRNA expression is a signature feature across multiple tumour types; however, their specific tumorigenic functions remain unclear. In this article, we discuss the emerging functional roles of piRNAs in a variety of cancers, and highlight their potential clinical utilities.


Asunto(s)
Neoplasias/genética , ARN Interferente Pequeño/metabolismo , Regulación Neoplásica de la Expresión Génica , Células Germinativas/metabolismo , Humanos , Modelos Biológicos , Neoplasias/diagnóstico , Pronóstico
12.
J Biol Chem ; 288(27): 19401-13, 2013 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-23696641

RESUMEN

Incorporation of selenium into ~25 mammalian selenoproteins occurs by translational recoding whereby in-frame UGA codons are redefined to encode the selenium containing amino acid, selenocysteine (Sec). Here we applied ribosome profiling to examine the effect of dietary selenium levels on the translational mechanisms controlling selenoprotein synthesis in mouse liver. Dietary selenium levels were shown to control gene-specific selenoprotein expression primarily at the translation level by differential regulation of UGA redefinition and Sec incorporation efficiency, although effects on translation initiation and mRNA abundance were also observed. Direct evidence is presented that increasing dietary selenium causes a vast increase in ribosome density downstream of UGA-Sec codons for a subset of selenoprotein mRNAs and that the selenium-dependent effects on Sec incorporation efficiency are mediated in part by the degree of Sec-tRNA([Ser]Sec) Um34 methylation. Furthermore, we find evidence for translation in the 5'-UTRs for a subset of selenoproteins and for ribosome pausing near the UGA-Sec codon in those mRNAs encoding the selenoproteins most affected by selenium availability. These data illustrate how dietary levels of the trace element selenium can alter the readout of the genetic code to affect the expression of an entire class of proteins.


Asunto(s)
Codón de Terminación/metabolismo , Suplementos Dietéticos , Biosíntesis de Proteínas/fisiología , Selenio/farmacología , Selenocisteína/metabolismo , Selenoproteínas/biosíntesis , Animales , Codón de Terminación/genética , Hígado/metabolismo , Masculino , Ratones , Ratones Transgénicos , Biosíntesis de Proteínas/efectos de los fármacos , ARN de Transferencia Aminoácido-Específico/genética , ARN de Transferencia Aminoácido-Específico/metabolismo , Selenocisteína/genética
14.
Nurs Outlook ; 62(6): 475-81, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25015410

RESUMEN

Recent years have yielded substantial advancement by clinical track faculty in cohort expansion and collective contributions to the discipline of nursing. As a result, standards for progression and promotion for clinical faculty need to be more fully developed, articulated, and disseminated. Our school formed a task force to examine benchmarks for the progression and promotion of clinical faculty across schools of nursing, with the goal of guiding faculty, reviewers, and decision makers about what constitutes excellence in scholarly productivity. Results from analyses of curriculum vitae of clinical professors or associate professors at six universities with high research activity revealed a variety of productivity among clinical track members, which included notable diversity in the types of scholarly products. Findings from this project help quantify types of scholarship for clinical faculty at the time of promotion. This work provides a springboard for greater understanding of the contributions of clinical track faculty to nursing practice.


Asunto(s)
Benchmarking/estadística & datos numéricos , Investigación en Enfermería Clínica/organización & administración , Educación en Enfermería/estadística & datos numéricos , Evaluación Educacional/estadística & datos numéricos , Eficiencia Organizacional/estadística & datos numéricos , Docentes de Enfermería/estadística & datos numéricos , Informe de Investigación , Educación en Enfermería/organización & administración , Evaluación Educacional/métodos , Humanos , Mejoramiento de la Calidad/estadística & datos numéricos , Estados Unidos
15.
J Control Release ; 367: 27-44, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38215984

RESUMEN

Efficient delivery of therapeutics to the central nervous system (CNS) remains a major challenge for the treatment of neurological diseases. Huntington disease (HD) is a dominantly inherited neurodegenerative disorder caused by a CAG trinucleotide expansion mutation in the HTT gene which codes for a toxic mutant huntingtin (mHTT) protein. Pharmacological reduction of mHTT in the CNS using antisense oligonucleotides (ASO) ameliorates HD-like phenotypes in rodent models of HD, with such therapies being investigated in clinical trials for HD. In this study, we report the optimization of apolipoprotein A-I nanodisks (apoA-I NDs) as vehicles for delivery of a HTT-targeted ASO (HTT ASO) to the brain and peripheral organs for HD. We demonstrate that apoA-I wild type (WT) and the apoA-I K133C mutant incubated with a synthetic lipid, 1,2-dimyristoyl-sn-glycero-3-phosphocholine, can self-assemble into monodisperse discoidal particles with diameters <20 nm that transmigrate across an in vitro blood-brain barrier model of HD. We demonstrate that apoA-I NDs are well tolerated in vivo, and that apoA-I K133C NDs show enhanced distribution to the CNS and peripheral organs compared to apoA-I WT NDs following systemic administration. ApoA-I K133C conjugated with HTT ASO forms NDs (HTT ASO NDs) that induce significant mHTT lowering in the liver, skeletal muscle and heart as well as in the brain when delivered intravenously in the BACHD mouse model of HD. Furthermore, HTT ASO NDs increase the magnitude of mHTT lowering in the striatum and cortex compared to HTT ASO alone following intracerebroventricular administration. These findings demonstrate the potential utility of apoA-I NDs as biocompatible vehicles for enhancing delivery of mutant HTT lowering ASOs to the CNS and peripheral organs for HD.


Asunto(s)
Enfermedad de Huntington , Oligonucleótidos Antisentido , Ratones , Animales , Oligonucleótidos Antisentido/uso terapéutico , Apolipoproteína A-I/genética , Enfermedad de Huntington/tratamiento farmacológico , Enfermedad de Huntington/genética , Oligonucleótidos/uso terapéutico , Encéfalo/metabolismo , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Proteína Huntingtina/uso terapéutico , Modelos Animales de Enfermedad
16.
PLoS Pathog ; 7(6): e1002081, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21695241

RESUMEN

Pandemic 2009 H1N1 influenza A virus (2009 H1N1) differs from H1N1 strains that circulated in the past 50 years, but resembles the A/New Jersey/1976 H1N1 strain used in the 1976 swine influenza vaccine. We investigated whether sera from persons immunized with the 1976 swine influenza or recent seasonal influenza vaccines, or both, neutralize 2009 H1N1. Using retroviral pseudovirions bearing hemagglutinins on their surface (HA-pseudotypes), we found that 77% of the sera collected in 1976 after immunization with the A/New Jersey/1976 H1N1 swine influenza vaccine neutralized 2009 H1N1. Forty five percent also neutralized A/New Caledonia/20/1999 H1N1, a strain used in seasonal influenza vaccines during the 2000/01-2006/07 seasons. Among adults aged 48-64 who received the swine influenza vaccine in 1976 and recent seasonal influenza vaccines during the 2004/05-2008/09 seasons, 83% had sera that neutralized 2009 H1N1. However, 68% of age-matched subjects who received the same seasonal influenza vaccines, but did not receive the 1976 swine influenza vaccine, also had sera that neutralized 2009 H1N1. Sera from both 1976 and contemporary cohorts frequently had cross-neutralizing antibodies to 2009 H1N1 and A/New Caledonia/20/1999 that mapped to hemagglutinin subunit 2 (HA2). A conservative mutation in HA2 corresponding to a residue in the A/Solomon Islands/3/2006 and A/Brisbane/59/2007 H1N1 strains that circulated in the 2006/07 and 2007/08 influenza seasons, respectively, abrogated this neutralization. These findings highlight a cross-neutralization determinant influenced by a point mutation in HA2 and suggest that HA2 may be evolving under direct or indirect immune pressure.


Asunto(s)
Anticuerpos Neutralizantes , Reacciones Cruzadas/inmunología , Hemaglutininas/genética , Subtipo H1N1 del Virus de la Influenza A/inmunología , Mutación Puntual , Línea Celular , Humanos , Subtipo H1N1 del Virus de la Influenza A/clasificación , Vacunas contra la Influenza/inmunología , Pandemias , Subunidades de Proteína/genética , Estaciones del Año , Vacunación
17.
Nurs Philos ; 14(4): 271-83, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24034158

RESUMEN

Opinion leaders are informal leaders who have the ability to influence others' decisions about adopting new products, practices or ideas. In the healthcare setting, the importance of translating new research evidence into practice has led to interest in understanding how opinion leaders could be used to speed this process. Despite continued interest, gaps in understanding opinion leadership remain. Agent-based models are computer models that have proven to be useful for representing dynamic and contextual phenomena such as opinion leadership. The purpose of this paper is to describe the work conducted in preparation for the development of an agent-based model of nursing opinion leadership. The aim of this phase of the model development project was to clarify basic assumptions about opinions, the individual attributes of opinion leaders and characteristics of the context in which they are effective. The process used to clarify these assumptions was the construction of a preliminary nursing opinion leader model, derived from philosophical theories about belief formation.


Asunto(s)
Liderazgo , Modelos de Enfermería , Teoría de Enfermería , Filosofía en Enfermería , Enfermería Basada en la Evidencia , Humanos
18.
PLoS One ; 18(5): e0285115, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37195973

RESUMEN

Competing theoretical perspectives about whether or not climate is the dominant factor influencing species' distributions at large spatial scales have important consequences when habitat suitability models are used to address conservation problems. In this study, we tested how much variables in addition to climate help to explain habitat suitability for Arctic-breeding shorebirds. To do this we model species occupancy using path analyses, which allow us to estimate the indirect effects of climate on other predictor variables, such as land cover. We also use deviance partitioning to quantify the total relative importance of climate versus additional predictors in explaining species occupancy. We found that individual land cover variables are often stronger predictors than the direct and indirect effects of climate combined. In models with both climate and additional variables, on average the additional variables accounted for 57% of the explained deviance, independent of shared effects with the climate variables. Our results support the idea that climate-only models may offer incomplete descriptions of current and future habitat suitability and can lead to incorrect conclusions about the size and location of suitable habitat. These conclusions could have important management implications for designating protected areas and assessing threats like climate change and human development.


Asunto(s)
Cambio Climático , Ecosistema , Humanos , Regiones Árticas , Predicción , Conservación de los Recursos Naturales
19.
Ecol Evol ; 13(2): e9797, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36778838

RESUMEN

Aim: To test whether the occupancy of shorebirds has changed in the eastern Canadian Arctic, and whether these changes could indicate that shorebird distributions are shifting in response to long-term climate change. Location: Foxe Basin and Rasmussen Lowlands, Nunavut, Canada. Methods: We used a unique set of observations, made 25 years apart, using general linear models to test if there was a relationship between changes in shorebird species' occupancy and their species temperature Index, a simple version of a species climate envelope. Results: Changes in occupancy and density varied widely across species, with some increasing and some decreasing. This is despite that overall population trends are known to be negative for all of these species based on surveys during migration. The changes in occupancy that we observed were positively related to the species temperature index, such that the warmer-breeding species appear to be moving into these regions, while colder-breeding species appear to be shifting out of the regions, likely northward. Main Conclusions: Our results suggest that we should be concerned about declining breeding habitat availability for bird species whose current breeding ranges are centered on higher and colder latitudes.

20.
J Control Release ; 360: 913-927, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37468110

RESUMEN

Lowering mutant huntingtin (mHTT) in the central nervous system (CNS) using antisense oligonucleotides (ASOs) is a promising approach currently being evaluated in clinical trials for Huntington disease (HD). However, the therapeutic potential of ASOs in HD patients is limited by their inability to cross the blood-brain barrier (BBB). In non-human primates, intrathecal infusion of ASOs results in limited brain distribution, with higher ASO concentrations in superficial regions and lower concentrations in deeper regions, such as the basal ganglia. To address the need for improved delivery of ASOs to the brain, we are evaluating the therapeutic potential of apolipoprotein A-I nanodisks (apoA-I NDs) as novel delivery vehicles for mHTT-lowering ASOs to the CNS after intranasal administration. Here, we have demonstrated the ability of apoA-I nanodisks to bypass the BBB after intranasal delivery in the BACHD model of HD. Following intranasal administration of apoA-I NDs, apoA-I protein levels were elevated along the rostral-caudal brain axis, with highest levels in the most rostral brain regions including the olfactory bulb and frontal cortex. Double-label immunohistochemistry indicates that both the apoA-I and ASO deposit in neurons. Most importantly, a single intranasal dose of apoA-I ASO-NDs significantly reduces mHTT levels in the brain regions most affected in HD, namely the cortex and striatum. This approach represents a novel non-invasive means for improving delivery and brain distribution of oligonucleotide therapies and enhancing likelihood of efficacy. Improved ASO delivery to the brain has widespread application for treatment of many other CNS disorders.


Asunto(s)
Enfermedad de Huntington , Oligonucleótidos Antisentido , Animales , Oligonucleótidos Antisentido/uso terapéutico , Apolipoproteína A-I/genética , Encéfalo/metabolismo , Barrera Hematoencefálica/metabolismo , Enfermedad de Huntington/tratamiento farmacológico , Enfermedad de Huntington/metabolismo , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo
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