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1.
Trials ; 25(1): 339, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778336

RESUMEN

INTRODUCTION: Informed consent for participation in an RCT is an important ethical and legal requirement. In placebo surgical trials, further issues are raised, and to date, this has not been explored. Patient information leaflets (PILs) are a core component of the informed consent process. This study aimed to investigate the key content of PILs for recently completed placebo-controlled trials of invasive procedures, including surgery, to highlight areas of good practice, identify gaps in information provision for trials of this type and provide recommendations for practice. METHODS: PILs were sought from trials included in a recent systematic review of placebo-controlled trials of invasive procedures, including surgery. Trial characteristics and data on surgical and placebo interventions under evaluation were extracted. Directed content analysis was applied, informed by published regulatory and good practice guidance on PIL content and existing research on placebo-controlled surgical trials. Results were analysed using descriptive statistics and presented as a narrative summary. RESULTS: Of the 62 eligible RCTs, authors of 59 trials were contactable and 14 PILs were received for analysis. At least 50% of all PILs included content on general trial design. Explanations of how the placebo differs or is similar to the surgical intervention (i.e. fidelity) were reported in 6 (43%) of the included PILs. Over half (57%) of the PILs included information on the potential therapeutic benefits of the surgical intervention. One (7%) included information on potential indirect therapeutic benefits from invasive components of the placebo. Five (36%) presented the known risks of the placebo intervention, whilst 8 (57%) presented information on the known risks of the surgical intervention. A range of terms was used across the PILs to describe the placebo component, including 'control', 'mock' and 'sham'. CONCLUSION: Developers of PILs for placebo-controlled surgical trials should carefully consider the use of language (e.g. sham, mock), be explicit about how the placebo differs (or is similar) to the surgical intervention and provide balanced presentations of potential benefits and risks of the surgical intervention separately from the placebo. Further research is required to determine optimal approaches to design and deliver this information for these trials.


Asunto(s)
Consentimiento Informado , Folletos , Educación del Paciente como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Procedimientos Quirúrgicos Operativos , Humanos , Consentimiento Informado/normas , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Procedimientos Quirúrgicos Operativos/normas , Procedimientos Quirúrgicos Operativos/efectos adversos , Efecto Placebo , Proyectos de Investigación/normas , Placebos , Comprensión
2.
J Neurol Sci ; 446: 120579, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36807973

RESUMEN

Following vestibular neuritis (VN), long term prognosis is not dependent on the magnitude of the residual peripheral function as measured with either caloric or the video head-impulse test. Rather, recovery is determined by a combination of visuo-vestibular (visual dependence), psychological (anxiety) and vestibular perceptual factors. Our recent research in healthy individuals has also revealed a strong association between the degree of lateralisation of vestibulo-cortical processing and gating of vestibular signals, anxiety and visual dependence. In the context of several functional brain changes occurring in the interaction between visual, vestibular and emotional cortices, which underpin the aforementioned psycho-physiological features in patients with VN, we re-examined our previously published findings focusing on additional factors impacting long term clinical outcome and function. These included: (i) the role of concomitant neuro-otological dysfunction (i.e. migraine and benign paroxysmal positional vertigo (BPPV)) and (ii) the degree to which brain lateralisation of vestibulo-cortical processing influences gating of vestibular function in the acute stage. We found that migraine and BPPV interfere with symptomatic recovery following VN. That is, dizziness handicap at short-term recovery stage was significantly predicted by migraine (r = 0.523, n = 28, p = .002), BPPV (r = 0.658, n = 31, p < .001) and acute visual dependency (r = 0.504, n = 28, p = .003). Moreover, dizziness handicap in the long-term recovery stage continued to be predicted by migraine (r = 0.640, n = 22, p = .001), BPPV (r = 0.626, n = 24, p = .001) and acute visual dependency (r = 0.667, n = 22, p < .001). Furthermore, surrogate measures of vestibulo-cortical lateralisation were predictive of the amount of cortical suppression exerted over vestibular thresholds. That is, in right-sided VN patients, we observed a positive correlation between visual dependence and acute ipsilesional oculomotor thresholds (R2 0.497; p < .001), but not contralateral thresholds (R2 0.017: p > .05). In left-sided VN patients, we observed a negative correlation between visual dependence and ipsilesional oculomotor thresholds (R2 0.459; p < .001), but not for contralateral thresholds (R2 0.013; p > .05). To surmise, our findings illustrate that in VN, neuro-otological co-morbidities retard recovery, and that measures of the peripheral vestibular system are an aggregate of residual function and cortically mediated gating of vestibular input.


Asunto(s)
Trastornos Migrañosos , Neuronitis Vestibular , Humanos , Mareo/complicaciones , Estudios Prospectivos , Vértigo/complicaciones , Trastornos Migrañosos/complicaciones
3.
Plant Biol (Stuttg) ; 24(5): 745-757, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35373433

RESUMEN

Quercus spp. are one of the most important tree genera in temperate deciduous forests in terms of biodiversity, economic and cultural perspectives. However, natural regeneration of oaks, depending on specific environmental conditions, is still not sufficiently understood. Oak regeneration dynamics are impacted by climate change, but these climate impacts will depend on local forest management and light and temperature conditions. Here, we studied germination, survival and seedling performance (i.e. aboveground biomass, height, root collar diameter and specific leaf area) of four oak species (Q. cerris, Q. ilex, Q. robur and Q. petraea). Acorns were sown across a wide latitudinal gradient, from Italy to Sweden, and across several microclimatic gradients located within and beyond the species' natural ranges. Microclimatic gradients were applied in terms of forest structure, distance to the forest edge and experimental warming. We found strong interactions between species and latitude, as well as between microclimate and latitude or species. The species thus reacted differently to local and regional changes in light and temperature ; in southern regions the temperate Q. robur and Q. petraea performed best in plots with a complex structure, whereas the Mediterranean Q. ilex and Q. cerris performed better in simply structured forests with a reduced microclimatic buffering capacity. The experimental warming treatment only enhanced height and aboveground biomass of Mediterranean species. Our results show that local microclimatic gradients play a key role in the initial stages of oak regeneration; however, one needs to consider the species-specific responses to forest structure and the macroclimatic context.


Asunto(s)
Quercus , Cambio Climático , Bosques , Microclima , Quercus/fisiología , Árboles
4.
Br J Surg ; 107(9): 1114-1122, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32187680

RESUMEN

BACKGROUND: Placebo-controlled trials play an important role in the evaluation of healthcare interventions. However, they can be challenging to design and deliver for invasive interventions, including surgery. In-depth understanding of the component parts of the treatment intervention is needed to ascertain what should, and should not, be delivered as part of the placebo. Assessment of risk to patients and strategies to ensure that the placebo effectively mimics the treatment are also required. To date, no guidance exists for the design of invasive placebo interventions. This study aimed to develop a framework to optimize the design and delivery of invasive placebo interventions in RCTs. METHODS: A preliminary framework was developed using published literature to: expand the scope of an existing typology, which facilitates the deconstruction of invasive interventions; and identify placebo optimization strategies. The framework was refined after consultation with key stakeholders in surgical trials, consensus methodology and medical ethics. RESULTS: The resulting DITTO framework consists of five stages: deconstruct treatment intervention into constituent components and co-interventions; identify critical surgical element(s); take out the critical element(s); think risk, feasibility and role of placebo in the trial when considering remaining components; and optimize placebo to ensure effective blinding of patients and trial personnel. CONCLUSION: DITTO considers invasive placebo composition systematically, accounting for risk, feasibility and placebo optimization. Use of the framework can support the design of high-quality RCTs, which are needed to underpin delivery of healthcare interventions.


ANTECEDENTES: Los ensayos controlados con placebo juegan un papel importante en la evaluación de las intervenciones sanitarias. Sin embargo, pueden ser difíciles de diseñar e implementar en el caso de intervenciones invasivas, incluida la cirugía. Se necesita un conocimiento profundo de los componentes de la intervención terapéutica (para determinar qué se debe y qué no se debe administrar como parte del placebo). También se precisa de una evaluación del riesgo para los pacientes y de las estrategias para garantizar que el placebo imite el tratamiento de forma efectiva. Hasta la fecha no existen guías para el diseño de intervenciones invasivas con placebo. Este estudio tuvo como objetivo desarrollar un marco para optimizar el diseño y la práctica de intervenciones invasivas con placebo dentro en los ensayos clínicos aleatorizados (ECA). MÉTODOS: Utilizando la literatura publicada, se desarrolló un marco preliminar para i) ampliar el alcance de los modelos existentes para facilitar la deconstrucción de las actuaciones invasivas, y ii) identificar estrategias para optimizar el placebo. El marco se perfeccionó tras consultar con partes interesadas ​​en ensayos quirúrgicos, metodología de consenso y ética médica. RESULTADOS: El marco DITTO resultantes consiste en cinco etapas: Etapa 1: deconstrucción de la intervención de tratamiento en sus componentes esenciales y co-intervenciones; Etapa 2: identificar el(los) elemento(s) quirúrgico(s) básico(s); Etapa 3: eliminar el(los) elemento(s) básico(s); Etapa 4: considerar el riesgo, la viabilidad y el papel del placebo en el ensayo al tener en cuenta los demás componentes; y Etapa 5: optimizar el placebo para garantizar el cegamiento efectivo de los pacientes y del personal del ensayo. CONCLUSIÓN: DITTO considera de forma sistemática la naturaleza invasiva del placebo, teniendo en cuenta el riesgo, la viabilidad y la optimización del placebo. El uso de este marco de referencia puede ayudar al diseño de ECAs de alta calidad, necesarios para afianzar la implementación de intervenciones sanitarias.


Asunto(s)
Placebos/normas , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Medición de Riesgo
5.
Psychol Med ; 50(1): 86-95, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30691541

RESUMEN

BACKGROUND: Improving quality of life (QOL) for people with dementia is a priority. In care homes, we often rely on proxy ratings from staff and family but we do not know if, or how, they differ in care homes. METHODS: We compared 1056 pairs of staff and family DEMQOL-Proxy ratings from 86 care homes across England. We explored factors associated with ratings quantitatively using multilevel modelling and, qualitatively, through thematic analysis of 12 staff and 12 relative interviews. RESULTS: Staff and family ratings were weakly correlated (ρs = 0.35). Median staff scores were higher than family's (104 v. 101; p < 0.001). Family were more likely than staff to rate resident QOL as 'Poor' (χ2 = 55.91, p < 0.001). Staff and family rated QOL higher when residents had fewer neuropsychiatric symptoms and severe dementia. Staff rated QOL higher in homes with lower staff:resident ratios and when staff were native English speakers. Family rated QOL higher when the resident had spent longer living in the care home and was a native English. Spouses rated residents' QOL higher than other relatives. Qualitative results suggest differences arise because staff felt good care provided high QOL but families compared the present to the past. Family judgements centre on loss and are complicated by decisions about care home placement and their understandings of dementia. CONCLUSION: Proxy reports differ systematically between staff and family. Reports are influenced by the rater:staff and family may conceptualise QOL differently.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Familia/psicología , Personal de Salud/psicología , Calidad de Vida , Anciano , Anciano de 80 o más Años , Demencia , Inglaterra , Femenino , Humanos , Masculino , Apoderado , Instituciones de Cuidados Especializados de Enfermería
6.
Plant Biol (Stuttg) ; 21(4): 677-687, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30659728

RESUMEN

Climate change is driving movements of many plants beyond, as well as within, their current distributional ranges. Even migrant plants moving within their current range may experience different plant-soil feedbacks (PSF) because of divergent nonlocal biotic soil conditions. Yet, our understanding to what extent soil biotic conditions can affect the performance of within-range migrant plants is still very limited. We assessed the emergence and growth of migrant forest herbs (Milium effusum and Stachys sylvatica) using soils and seeds collected along a 1,700 km latitudinal gradient across Europe. Soil biota were manipulated through four soil treatments, i.e. unsterilized control soil (PSFUS ), sterilized soil (PSFS ), sterilized soil inoculated with unsterilized home soil (PSFS+HI ) and sterilized soil inoculated with unsterilized foreign soil (PSFS+FI , expected to occur when both plants and soil biota track climate change). Compared to PSFS , PSFUS had negative effects on the growth but not emergence of both species, while PSFS+FI only affected S. sylvatica across all seed provenances. When considering seed origin, seedling emergence and growth responses to nonlocal soils depended on soil biotic conditions. Specifically, the home-away distance effect on seedling emergence differed between the four treatments, and significant responses to chemistry either disappeared (M. effusum) or changed (S. sylvatica) from PSFUS to PSFS . Soil biota emerge as an important driver of the estimated plant migration success. Our results of the effects of soil microorganisms on plant establishment provide relevant information for predictions of the distribution and dynamics of plant species in a changing climate.


Asunto(s)
Bosques , Poaceae/crecimiento & desarrollo , Suelo , Stachys/crecimiento & desarrollo , Ecosistema , Retroalimentación Fisiológica , Microbiología del Suelo
7.
Plant Biol (Stuttg) ; 20(3): 619-626, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29323793

RESUMEN

Elevated atmospheric input of nitrogen (N) is currently affecting plant biodiversity and ecosystem functioning. The growth and survival of numerous plant species is known to respond strongly to N fertilisation. Yet, few studies have assessed the effects of N deposition on seed quality and reproductive performance, which is an important life-history stage of plants. Here we address this knowledge gap by assessing the effects of atmospheric N deposition on seed quality of the ancient forest herb Anemone nemorosa using two complementary approaches. By taking advantage of the wide spatiotemporal variation in N deposition rates in pan-European temperate and boreal forests over 2 years, we detected positive effects of N deposition on the N concentration (percentage N per unit seed mass, increased from 2.8% to 4.1%) and N content (total N mass per seed more than doubled) of A. nemorosa seeds. In a complementary experiment, we applied ammonium nitrate to aboveground plant tissues and the soil surface to determine whether dissolved N sources in precipitation could be incorporated into seeds. Although the addition of N to leaves and the soil surface had no effect, a concentrated N solution applied to petals during anthesis resulted in increased seed mass, seed N concentration and N content. Our results demonstrate that N deposition on the petals enhances bioaccumulation of N in the seeds of A. nemorosa. Enhanced atmospheric inputs of N can thus not only affect growth and population dynamics via root or canopy uptake, but can also influence seed quality and reproduction via intake through the inflorescences.


Asunto(s)
Anemone/fisiología , Flores/metabolismo , Nitrógeno/metabolismo , Semillas/fisiología , Anemone/química , Anemone/metabolismo , Atmósfera , Clima , Europa (Continente) , Flores/química , Bosques , Nitrógeno/análisis , Reproducción/fisiología
8.
Plant Biol (Stuttg) ; 19(2): 201-210, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27741365

RESUMEN

Persistent seed banks are a key plant regeneration strategy, buffering environmental variation to allow population and species persistence. Understanding seed bank functioning within herb layer dynamics is therefore important. However, rather than assessing emergence from the seed bank in herb layer gaps, most studies evaluate the seed bank functioning via a greenhouse census. We hypothesise that greenhouse data may not reflect seed bank-driven emergence in disturbance gaps due to methodological differences. Failure in detecting (specialist) species may then introduce methodological bias into the ecological interpretation of seed bank functions using greenhouse data. The persistent seed bank was surveyed in 40 semi-natural grassland plots across a fragmented landscape, quantifying seedling emergence in both the greenhouse and in disturbance gaps. Given the suspected interpretational bias, we tested whether each census uncovers similar seed bank responses to fragmentation. Seed bank characteristics were similar between censuses. Census type affected seed bank composition, with >25% of species retrieved better by either census type, dependent on functional traits including seed longevity, production and size. Habitat specialists emerged more in disturbance gaps than in the greenhouse, while the opposite was true for ruderal species. Both censuses uncovered fragmentation-induced seed bank patterns. Low surface area sampling, larger depth of sampling and germination conditions cause underrepresentation of the habitat-specialised part of the persistent seed bank flora during greenhouse censuses. Methodological bias introduced in the recorded seed bank data may consequently have significant implications for the ecological interpretation of seed bank community functions based on greenhouse data.


Asunto(s)
Asteraceae/fisiología , Conservación de los Recursos Naturales , Banco de Semillas , Semillas/fisiología , Asteraceae/crecimiento & desarrollo , Ecosistema , Germinación , Pradera , Fenotipo , Plantones/crecimiento & desarrollo , Plantones/fisiología , Semillas/crecimiento & desarrollo
9.
J Neurol ; 262(12): 2764-72, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26477023

RESUMEN

Headache is being viewed more commonly in a biopsychosocial framework, which introduces the possible utilisation of psychological treatment options, such as cognitive behavioural therapy and relaxation. No such treatments have been trialled in the UK. We conducted a randomised controlled pilot trial, comparing a brief guided self-help CBT and relaxation treatment with standard medical care (SMC), in a UK NHS setting. Participants were recruited from specialist headache clinics across London. Participants were randomised to receive either treatment or standard medical care. Our objective was to provide design information necessary for a future definitive trial of the SHE treatment, including, recruitment/retention rates, acceptability of randomisation, treatment fidelity and estimations of mean and variances of outcome measures. From the initial 275 patients identified, 73 were randomised. There was no difference in drop-out rates between SMC and treatment groups. Of the 36 participants randomised to receive treatment, 72% attended all sessions. Findings show that a future definitive trial of the SHE treatment is feasible, with small modifications of protocol, within a UK NHS context.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Evaluación de Resultado en la Atención de Salud , Terapia por Relajación/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Migrañosos , Proyectos Piloto , Adulto Joven
10.
Am J Speech Lang Pathol ; 24(3): 533-44, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26125134

RESUMEN

PURPOSE: The present study presents treatment duration and outcome data on 14 children who stutter (CWS) recently treated by the Lidcombe Program (LP). These data were then combined with data from a previous LP treatment study (Miller & Guitar, 2009) to examine predictor variables for treatment duration and outcome. The present study also provides evidence of the effectiveness of LP from researchers who are independent of the developers of the program. METHOD: Fourteen preschool CWS were assessed on stuttering severity variables and participant characteristics prior to treatment, given LP treatment, and reassessed 2 years after the children achieved stable fluency. These children's data were added to the data of 15 previously treated CWS to examine predictors of treatment duration and long-term outcome. Preliminary analysis lead to the identification of two predictors that were tested in a generalized linear model. RESULTS: For the new group of 14 CWS, median treatment duration was 15 clinic visits and resulted in near-zero stuttering long term for most of the children and substantial reductions in stuttering for all of the children. For the combined group of 29 children, pretreatment stuttering frequency and severity were the best predictors of treatment duration in both clinic visits and weeks. CONCLUSIONS: Children with more frequent and more severe stuttering may take longer in LP treatment. Long-term outcome may best be predicted by pretreatment stuttering and sex.


Asunto(s)
Evaluación de Procesos y Resultados en Atención de Salud , Tartamudeo/terapia , Preescolar , Intervención Educativa Precoz , Femenino , Estudios de Seguimiento , Humanos , Masculino , Medición de la Producción del Habla , Tartamudeo/diagnóstico , Factores de Tiempo
11.
Plant Biol (Stuttg) ; 17(1): 52-62, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24750437

RESUMEN

Climate change is acting on several aspects of plant life cycles, including the sexual reproductive stage, which is considered amongst the most sensitive life-cycle phases. In temperate forests, it is expected that climate change will lead to a compositional change in community structure due to changes in the dominance of currently more abundant forest tree species. Increasing our understanding of the effects of climate change on currently secondary tree species recruitment is therefore important to better understand and forecast population and community dynamics in forests. Here, we analyse the interactive effects of rising temperatures and soil moisture reduction on germination, seedling survival and early growth of two important secondary European tree species, Acer pseudoplatanus and A. platanoides. Additionally, we analyse the effect of the temperature experienced by the mother tree during seed production by collecting seeds of both species along a 2200-km long latitudinal gradient. For most of the responses, A. platanoides showed higher sensitivity to the treatments applied, and especially to its joint manipulation, which for some variables resulted in additive effects while for others only partial compensation. In both species, germination and survival decreased with rising temperatures and/or soil moisture reduction while early growth decreased with declining soil moisture content. We conclude that although A. platanoides germination and survival were more affected after the applied treatments, its initial higher germination and larger seedlings might allow this species to be relatively more successful than A. pseudoplatanus in the face of climate change.


Asunto(s)
Acer/fisiología , Cambio Climático , Sequías , Germinación , Regeneración , Plantones/fisiología , Semillas/fisiología , Suelo/química , Temperatura , Árboles
12.
Plant Biol (Stuttg) ; 15(1): 195-202, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22646655

RESUMEN

Many recent studies have explored the effects of present and past landscape structure on species distribution and diversity. However, we know little about the effects of past landscape structure on distribution of genetic diversity within and between populations of a single species. Here we describe the relationship between present and past landscape structure (landscape connectivity and habitat size estimated from historical maps) and current genetic structure in a perennial herb, Succisa pratensis. We used allozymes as co-dominant markers to estimate genetic diversity and deviation from Hardy-Weinberg equilibrium in 31 populations distributed within a 5 km(2) agricultural landscape. The results showed that current genetic diversity of populations was related to habitat suitability, habitat age, habitat size and habitat connectivity in the past. The effects of habitat age and past connectivity on genetic diversity were in most cases also significant after taking the current landscape structure into account. Moreover, current genetic similarity between populations was affected by past connectivity after accounting for current landscape structure. In both cases, the oldest time layer (1850) was the most informative. Most populations showed heterozygote excess, indicating disequilibrium due to recent gene flow or selection against homozygotes. These results suggest that habitat age and past connectivity are important determinants of distribution of genetic diversity between populations at a scale of a few kilometres. Landscape history may significantly contribute to our understanding of distribution of current genetic structure within species and the genetic structure may be used to better understand landscape history, even at a small scale.


Asunto(s)
Dipsacaceae/genética , Ecosistema , Estructuras Genéticas , Variación Genética , Genética de Población , Alelos , Ambiente , Flujo Génico , Marcadores Genéticos/genética , Heterocigoto , Endogamia , Isoenzimas/genética , Proteínas de Plantas/genética , Análisis de Regresión , Selección Genética
13.
Plant Biol (Stuttg) ; 13(3): 493-501, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21489100

RESUMEN

The nutrient concentration in seeds determines many aspects of potential success of the sexual reproductive phase of plants, including the seed predation probability, efficiency of seed dispersal and seedling performance. Despite considerable research interest in latitudinal gradients of foliar nutrients, a similar gradient for seeds remains unexplored. We investigated a potential latitudinal gradient in seed nutrient concentrations within the widespread European understorey forest herb Anemone nemorosa L. We sampled seeds of A. nemorosa in 15 populations along a 1900-km long latitudinal gradient at three to seven seed collection dates post-anthesis and investigated the relative effects of growing degree-hours >5 °C, soil characteristics and latitude on seed nutrient concentrations. Seed nitrogen, nitrogen:phosphorus ratio and calcium concentration decreased towards northern latitudes, while carbon:nitrogen ratios increased. When taking differences in growing degree-hours and measured soil characteristics into account and only considering the most mature seeds, the latitudinal decline remained particularly significant for seed nitrogen concentration. We argue that the decline in seed nitrogen concentration can be attributed to northward decreasing seed provisioning due to lower soil nitrogen availability or greater investment in clonal reproduction. This pattern may have large implications for the reproductive performance of this forest herb as the degree of seed provisioning ultimately co-determines seedling survival and reproductive success.


Asunto(s)
Anemone/química , Semillas/química , Árboles , Anemone/metabolismo , Calcio/análisis , Calcio/metabolismo , Europa (Continente) , Geografía , Nitrógeno/análisis , Nitrógeno/metabolismo , Fósforo/análisis , Fósforo/metabolismo , Semillas/metabolismo , Suelo/química
14.
Neuroscience ; 158(1): 89-95, 2009 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-18308477

RESUMEN

N-methyl-D-aspartate (NMDA) receptors are clustered at synapses via their association with the PSD-95 (post-synaptic density-95) membrane associated guanylate kinase (MAGUK) family of scaffolding proteins. PSD-95 is the best characterized of this family. It is known to associate with NMDA receptor NR2 subunits via a conserved ES(E/D)V amino acid sequence located at their C-termini and thus to promote the clustering, regulation and the trafficking of assembled NR1/NR2 NMDA receptors at synapses. Here we have investigated in more detail NMDA receptor NR2/PSD-95 protein-protein association. Wild-type NR1 and PSD-95alpha were co-expressed with a series of rodent C-terminal truncated constructs of either NR2A or NR2B subunits in human embryonic kidney (HEK) 293 cells and the association of PSD-95alpha with assembled receptors determined by immunoprecipitation. Additional PSD-95 binding domains that differed between NR2A and NR2B subunits were identified. These domains mapped to the amino acid sequences NR2A (1382-1420) and NR2B (1086-1157). These results suggest that NR2A and NR2B may associate with PSD-95 but with different affinities. This may be important in the determination of the lateral mobility of NMDA receptor subtypes in post-synaptic membranes.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapsis/metabolismo , Membranas Sinápticas/metabolismo , Secuencia de Aminoácidos/fisiología , Animales , Sitios de Unión/fisiología , Línea Celular , Homólogo 4 de la Proteína Discs Large , Humanos , Péptidos y Proteínas de Señalización Intracelular/química , Sustancias Macromoleculares/química , Sustancias Macromoleculares/metabolismo , Proteínas de la Membrana/química , Datos de Secuencia Molecular , Unión Proteica/fisiología , Estructura Terciaria de Proteína/fisiología , Transporte de Proteínas/fisiología , Receptores de N-Metil-D-Aspartato/química , Roedores , Homología de Secuencia de Aminoácido , Sinapsis/ultraestructura , Membranas Sinápticas/ultraestructura , Transmisión Sináptica/fisiología
15.
Br J Ophthalmol ; 92(2): 191-6, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17962393

RESUMEN

AIMS: We compared the effectiveness and durability of indocyanine green angiography (ICG) directed focal thermal laser treatment of the afferent arteriole in the treatment of retinal angiomatous proliferation (RAP). METHODS: Sixteen consecutive patients presenting with stage I or II RAP lesions underwent optical coherence tomography, fluorescein angiography and dynamic ICG examination and were evaluated for response to treatment. Two groups were evaluated: focal laser as initial treatment; and focal laser as salvage treatment after recurrence with photodynamic therapy (PDT) and intravitreal triamcinolone. Five additional eyes with stage III RAP were evaluated separately. RESULTS: Seven eyes received focal laser as initial treatment, and nine eyes received focal laser as salvage treatment after failure of PDT with triamcinolone. Five of seven eyes in the initial focal laser group demonstrated resolution of oedema. All five of the responders recurred (mean 4.4 months). Salvage therapy with PDT and triamcinolone after focal laser failure transiently closed these recurrences. In contrast, eight of nine eyes receiving thermal ablation of the RAP lesion after recurrence from prior PDT/triamcinolone demonstrated initial improvement of the retinal oedema. Four eyes demonstrated no recurrence within a year. None of the five eyes with stage III RAP improved anatomically or visually. CONCLUSION: Focal thermal laser treatment of RAP arteriole can resolve retinal oedema. However, durability was longer in eyes with prior PDT and triamcinolone treatment than those receiving thermal laser as initial therapy. These results suggest that focal laser may be useful in treatment of RAP recurrences and that combination therapy with PDT/triamcinolone plus focal laser is better than focal laser alone.


Asunto(s)
Angiomatosis/cirugía , Coagulación con Láser/métodos , Degeneración Macular/cirugía , Neovascularización Retiniana/cirugía , Anciano , Angiomatosis/diagnóstico , Angiomatosis/tratamiento farmacológico , Colorantes , Terapia Combinada , Femenino , Angiografía con Fluoresceína , Estudios de Seguimiento , Glucocorticoides/uso terapéutico , Humanos , Verde de Indocianina , Degeneración Macular/diagnóstico , Degeneración Macular/tratamiento farmacológico , Masculino , Fotoquimioterapia , Recurrencia , Neovascularización Retiniana/diagnóstico , Neovascularización Retiniana/tratamiento farmacológico , Terapia Recuperativa/métodos , Tomografía de Coherencia Óptica , Insuficiencia del Tratamiento , Resultado del Tratamiento , Triamcinolona/uso terapéutico
17.
Nucleic Acids Res ; 33(Database issue): D471-5, 2005 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-15608240

RESUMEN

The Mouse Genome Database (MGD) forms the core of the Mouse Genome Informatics (MGI) system (http://www.informatics.jax.org), a model organism database resource for the laboratory mouse. MGD provides essential integration of experimental knowledge for the mouse system with information annotated from both literature and online sources. MGD curates and presents consensus and experimental data representations of genotype (sequence) through phenotype information, including highly detailed reports about genes and gene products. Primary foci of integration are through representations of relationships among genes, sequences and phenotypes. MGD collaborates with other bioinformatics groups to curate a definitive set of information about the laboratory mouse and to build and implement the data and semantic standards that are essential for comparative genome analysis. Recent improvements in MGD discussed here include the enhancement of phenotype resources, the re-development of the International Mouse Strain Resource, IMSR, the update of mammalian orthology datasets and the electronic publication of classic books in mouse genetics.


Asunto(s)
Bases de Datos Genéticas , Genómica , Ratones/genética , Animales , Genes , Genoma , Genotipo , Internet , Ratones Mutantes , Fenotipo , Integración de Sistemas , Interfaz Usuario-Computador
18.
Arch Virol ; 150(4): 797-803, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15614430

RESUMEN

Although cell-mediated cytotoxicity effectively kills target virus-infected cells, no careful consideration has been given to the fate of infectious progeny virus contained within target cells following the cytolytic event. To address this issue with respect to murine cytomegalovirus (MCMV) pathogenesis, we developed a rapid semiquantitative assay for infectious MCMV based on expression of beta-galactosidase using a LacZ-expressing recombinant MCMV. Simultaneous use of this assay in combination with a modified cell-mediated cytotoxicity assay revealed that cytotoxicity of MCMV-infected target cells mediated by MCMV-immune splenic cells does not lead to inactivation of intracellular infectious virus.


Asunto(s)
Citomegalovirus/patogenicidad , Animales , Citomegalovirus/inmunología , Citomegalovirus/aislamiento & purificación , Citotoxicidad Inmunológica , Ratones , Proteínas Recombinantes/metabolismo , beta-Galactosidasa/metabolismo
19.
Arch Virol ; 149(11): 2235-44, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15503209

RESUMEN

Adoptive transfer studies were performed to test the hypothesis that the perforin cytotoxic pathway is more important than the Fas/FasL cytotoxic pathway in protection against experimental murine cytomegalovirus (MCMV) retinitis. Splenic immune cells from donor MCMV-immunized normal mice or gld mice deficient in Fas/FasL-mediated cytotoxicity significantly reduced the frequency and severity of MCMV retinitis following subretinal MCMV challenge when transferred into recipient PKO mice deficient in perforin-mediated cytotoxicity. In sharp contrast, splenic cells from donor MCMV-immunized PKO mice failed to provide protection against MCMV retinitis when transferred into recipient PKO mice. Protection was not achieved, however, in recipient mice with retrovirus-induced immunodeficiency (MAIDS), even when splenic cells originated from MCMV-immunized normal mice.


Asunto(s)
Traslado Adoptivo , Retinitis por Citomegalovirus/prevención & control , Citotoxicidad Inmunológica , Glicoproteínas de Membrana/fisiología , Síndrome de Inmunodeficiencia Adquirida del Murino/inmunología , Muromegalovirus/inmunología , Animales , Inmunización , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Perforina , Proteínas Citotóxicas Formadoras de Poros
20.
Nucleic Acids Res ; 32(Database issue): D476-81, 2004 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-14681461

RESUMEN

The Mouse Genome Database (MGD) is one component of the Mouse Genome Informatics (MGI) system (http://www.informatics.jax.org), a community database resource for the laboratory mouse. MGD strives to provide a comprehensive knowledgebase about the mouse with experiments and data annotated from both literature and online sources. MGD curates and presents consensus and experimental data representations of genetic, genotype (sequence) and phenotype information including highly detailed reports about genes and gene products. Primary foci of integration are through representations of relationships between genes, sequences and phenotypes. MGD collaborates with other bioinformatics groups to curate a definitive set of information about the laboratory mouse and to build and implement the data and semantic standards that are essential for comparative genome analysis. Recent developments in MGD discussed here include an extensive integration of the mouse sequence data and substantial revisions in the presentation, query and visualization of sequence data.


Asunto(s)
Biología Computacional , Bases de Datos Genéticas , Genoma , Ratones/genética , Animales , Genómica , Almacenamiento y Recuperación de la Información , Internet , Biología Molecular , Fenotipo , Terminología como Asunto
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