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1.
Landsc Ecol ; 38(12): 3173-3188, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38161780

RESUMEN

Context: Industrial development in Canada's boreal forest creates cumulative environmental effects on biodiversity. Some effects may be scale-dependent, creating uncertainty in understanding and hindering effective management. Objectives: We estimated cumulative effects of energy sector development on distributions of sixteen migratory songbird species at multiple spatial scales within the boreal region of Alberta, Canada, and evaluated evidence for scale domains in species responses. Methods: We used a hierarchical, multi-scale sampling and modelling framework to compare effects of oil and gas footprint on songbirds at five spatial scales. We used Bayesian Lasso to facilitate direct comparison of parameter estimates across scales, and tested for differences in grouped parameter estimates among species. Results: We found consistent scale-dependent patterns across species, showing variable responses to development occurring at the smallest scale, little effect at intermediate scales, and stronger, mainly positive effects at the largest scales. Differences in grouped parameter estimates across scales showed strong evidence for scale domains in the response of songbirds to energy sector development. Conclusions: We concluded that variable effects at the smallest scale represented individual habitat selection, while larger scale positive effects reflected expanding distributions of open habitat- and disturbance-associated species in areas of high oil and gas footprint. Our results show that single-scale analyses do not reflect population processes occurring at other scales. Future research on linking patterns at different scales is required to fully understand cumulative effects of land use change on wildlife populations. Supplementary Information: The online version contains supplementary material available at 10.1007/s10980-023-01779-8.

2.
Clin Radiol ; 76(1): 73.e21-73.e37, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-31879023

RESUMEN

Transcatheter aortic valve implantation (TAVI) is an alternative to surgical aortic valve replacement in selected patients with severe symptomatic aortic stenosis (AS) and high surgical risk. The planning and follow-up of TAVI requires an array of imaging techniques, each has advantages and limitations. Echocardiography and multidetector computer tomography (MDCT) have established applications in patient selection and procedure guidance, but are limited in some patients. TAVI applications of cardiovascular magnetic resonance imaging (CMRI) are emerging. CMRI can provide the structural and functional imaging details required for TAVI procedure in away comparable or superior to that obtained by echocardiography and MDCT combined. In this review, we look at the continuously evolving role of CMRI as a complimentary or an alternative to more established imaging techniques and address the advantages and disadvantages of CMRI in this setting. We discuss the role of CMRI in selecting anatomically suitable patients for the TAVI procedure and in the post-TAVI follow-up with particular emphasis on its applications for assessing AS severity and haemodynamic impact, vascular imaging for TAVI access route, quantification of paravalvular leaks and LV remodelling in the post TAVI setting as well as providing imaging biomarkers tool for AS risk-stratification.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Reemplazo de la Válvula Aórtica Transcatéter , Ecocardiografía , Fluoroscopía , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada Multidetector
4.
PLoS One ; 15(6): e0234494, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32544173

RESUMEN

Predicting and mitigating impacts of climate change and development within the boreal biome requires a sound understanding of factors influencing the abundance, distribution, and population dynamics of species inhabiting this vast biome. Unfortunately, the limited accessibility of the boreal biome has resulted in sparse and spatially biased sampling, and thus our understanding of boreal bird population dynamics is limited. To implement effective conservation of boreal birds, a cost-effective approach to sampling the boreal biome will be needed. Our objective was to devise a sampling scheme for monitoring boreal birds that would improve our ability to model species-habitat relationships and monitor changes in population size and distribution. A statistically rigorous design to achieve these objectives would have to be spatially balanced and hierarchically structured with respect to ecozones, ecoregions and political jurisdictions. Therefore, we developed a multi-stage hierarchically structured sampling design known as the Boreal Optimal Sampling Strategy (BOSS) that included cost constraints, habitat stratification, and optimization to provide a cost-effective alternative to other common monitoring designs. Our design provided similar habitat and spatial representation to habitat stratification and equal-probability spatially balanced designs, respectively. Not only was our design able to achieve the desired habitat representation and spatial balance necessary to meet our objectives, it was also significantly less expensive (1.3-2.6 times less) than the alternative designs we considered. To further balance trade-offs between cost and representativeness prior to field implementation, we ran multiple iterations of the BOSS design and selected the one which minimized predicted costs while maximizing a multi-criteria evaluation of representativeness. Field implementation of the design in three vastly different regions over three field seasons showed that the approach can be implemented in a wide variety of logistical scenarios and ecological conditions. We provide worked examples and scripts to allow our approach to be implemented or adapted elsewhere. We also provide recommendations for possible future refinements to our approach, but recommend that our design now be implemented to provide unbiased information to assess the status of boreal birds and inform conservation and management actions.


Asunto(s)
Aves/fisiología , Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Animales , Humanos , Dinámica Poblacional , Estaciones del Año , Taiga
6.
Ecol Appl ; 29(5): e01895, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31121076

RESUMEN

Stressors created by multiple resource industries can result in cumulative effects over time and space. Many studies have evaluated single stressors and assumed that cumulative effects can be understood by adding stressors together. However, there is growing evidence that interactive effects are important in structuring biological communities. We evaluated whether the effects of multiple stressors in the boreal forest (linear features, energy, forestry) combine additively or interactively by testing a candidate model set of 12 cumulative effects models of abundance for 27 landbird species. We fitted paired additive and interactive Generalized Additive Models and examined model predictions in the Athabasca Oil Sands Area of Alberta, Canada, and a theoretical no-disturbance version of the study area. Of the 27 species examined, an additive disturbance model was the best for nine species, while an interactive disturbance model was the best for 11 species. In the current study area, disturbance models predicted strong increases in abundance for species associated with deciduous forest and open habitats (winning species) and moderate decreases for species associated with conifer forest (losing species). We found a 15% change in landbird community composition between the current study area, with 8.4% disturbance, and the theoretical no-disturbance study area. Complex synergistic and antagonistic interactions among stressors were observed for 39% of landbird species, with the majority of interactions observed being synergistic. Stressors with relatively small disturbance areas, such as narrow linear disturbances, frequently interacted with other stressors to affect species' responses, and energy sector stressors often had additive or interactive effects with forestry stressors. Interactive cumulative effects from multiple sectors will make it increasingly difficult for industry and land managers to manage impacts unless interactions among stressors are incorporated into cumulative effects assessments and regional land use planning processes.


Asunto(s)
Ecosistema , Yacimiento de Petróleo y Gas , Alberta , Bosques , Taiga
9.
Occup Med (Lond) ; 64(3): 188-92, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24477502

RESUMEN

BACKGROUND: Technological advances mean that many adults are now employed in sedentary occupations. Given evidence linking prolonged sitting to chronic disease risk, understanding sitting and physical activity in and outside the workplace may usefully inform effective interventions. AIMS: To assess sitting time and physical activity during and outside working hours in full-time office workers. METHODS: Participants wore a pedometer and recorded sitting times and step counts during and outside working hours for 7 days. Participants were divided into tertiles based on the proportion of time spent sitting at work. Sitting times and step counts reported outside work were compared between groups, using one-way analysis of variance. RESULTS: There were 72 participants. Almost two-thirds (65%) of time at work was spent sitting. The sample accumulated 3742±2493 steps at work and 5159±2474 steps outside work on workdays. Participants in the highest tertile for workplace sitting reported sitting for longer than those in the lowest tertile during transport (64±59 versus 21±16min), after work (154±30 versus 126±51min) and at weekends (382±133 versus 288±124min, all P < 0.05). Work duration and steps reported outside work did not differ between groups. CONCLUSIONS: Office workers who sit for a large proportion of their working day also report sitting for longer outside work. They do not compensate for their sedentary behaviour at work by being more active outside work. Occupational health interventions should focus on reducing workplace and leisure-time sitting in sedentary office workers.


Asunto(s)
Actividades Recreativas , Exposición Profesional , Ocupaciones , Postura , Conducta Sedentaria , Caminata , Trabajo , Adulto , Femenino , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Lugar de Trabajo , Adulto Joven
11.
Clin Pharmacol Ther ; 92(2): 243-50, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22739139

RESUMEN

The type 1 neurokinin receptor (NK1R) antagonist aprepitant and its i.v. prodrug fosaprepitant have been approved for prevention of acute and delayed nausea and vomiting associated with chemotherapy. This study evaluated the magnitude and duration of brain NK1R occupancy over a period of 5 days after single-dose i.v. infusion of 150-mg fosaprepitant and single-dose oral administration of 165-mg aprepitant, using serial [(18)F]MK-0999 positron emission tomography (PET) in 16 healthy subjects. Each subject underwent three scans. Brain NK1R occupancy rates after i.v. fosaprepitant at time to peak concentration (T(max); ~30 min), 24, 48, and 120 h after the dose were 100, 100, ≥97, and 41-75%, respectively. After aprepitant, NK1R occupancy rates at these time points (T(max) ~4 h) were ≥99, ≥99, ≥97, and 37-76%, respectively. Aprepitant plasma concentration profiles were comparable for the two dosage forms. The study illustrates the utility of PET imaging in determining central bioequivalence in a limited number of subjects.


Asunto(s)
Antieméticos/administración & dosificación , Antineoplásicos/efectos adversos , Encéfalo/efectos de los fármacos , Morfolinas/administración & dosificación , Náusea/prevención & control , Antagonistas del Receptor de Neuroquinina-1 , Vómitos/prevención & control , Adulto , Aprepitant , Encéfalo/diagnóstico por imagen , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Morfolinas/farmacocinética , Náusea/inducido químicamente , Tomografía de Emisión de Positrones , Profármacos , Receptores de Neuroquinina-1/metabolismo , Equivalencia Terapéutica , Vómitos/inducido químicamente , Adulto Joven
12.
Environ Sci Technol ; 45(18): 7670-7, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21809844

RESUMEN

Radioactive emissions into the atmosphere from the damaged reactors of the Fukushima Dai-ichi nuclear power plant (NPP) started on March 12th, 2011. Among the various radionuclides released, iodine-131 ((131)I) and cesium isotopes ((137)Cs and (134)Cs) were transported across the Pacific toward the North American continent and reached Europe despite dispersion and washout along the route of the contaminated air masses. In Europe, the first signs of the releases were detected 7 days later while the first peak of activity level was observed between March 28th and March 30th. Time variations over a 20-day period and spatial variations across more than 150 sampling locations in Europe made it possible to characterize the contaminated air masses. After the Chernobyl accident, only a few measurements of the gaseous (131)I fraction were conducted compared to the number of measurements for the particulate fraction. Several studies had already pointed out the importance of the gaseous (131)I and the large underestimation of the total (131)I airborne activity level, and subsequent calculations of inhalation dose, if neglected. The measurements made across Europe following the releases from the Fukushima NPP reactors have provided a significant amount of new data on the ratio of the gaseous (131)I fraction to total (131)I, both on a spatial scale and its temporal variation. It can be pointed out that during the Fukushima event, the (134)Cs to (137)Cs ratio proved to be different from that observed after the Chernobyl accident. The data set provided in this paper is the most comprehensive survey of the main relevant airborne radionuclides from the Fukushima reactors, measured across Europe. A rough estimate of the total (131)I inventory that has passed over Europe during this period was <1% of the released amount. According to the measurements, airborne activity levels remain of no concern for public health in Europe.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Radioisótopos de Cesio/análisis , Radioisótopos de Yodo/análisis , Liberación de Radiactividad Peligrosa , Europa (Continente) , Japón , Plantas de Energía Nuclear , Monitoreo de Radiación
13.
Ir Med J ; 102(7): 207-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19771999

RESUMEN

Alcohol consumption in Ireland has nearly doubled during the period 1989-2001. To evaluate the relationship of alcohol to fatal head injuries in the acute hospital setting we created a data base of all fatal traumatic brain injuries in the Department of Neuropathology at Beaumont Hospital over a ten year period (1997-2006 inclusive). 498 cases were identified (351 males: 147 females). Fatalities were highest in males aged 19-25 years (N=101) and 51-70 years (N=109). Falls (N=210) and road traffic accidents (N=183) were the commonest modes of presentation. 36/210 (17%) falls had positive blood alcohol testing, 9/210 (4.3%) had documentation of alcohol in notes but no testing, 35/210 (16.7%) tested negative for alcohol and 130/210 (61.9%) were not tested. The RTA group (N=183) comprised drivers (n=79), passengers (n=47) and pedestrians (n=57). 65/79 (82.2%) of drivers were males aged 19-25 years. Blood alcohol was only available in 27/79 (34.1%) drivers and was positive in 13/27 (48.1%). 14/75 (18.7%) pedestrians were tested for alcohol, 4/14 (28.6%) were positive. Overall 142/183 (77.6%) of the RTA group were not tested. The contribution of alcohol to fatal traumatic brain injuries is probably being underestimated due to omission of blood alcohol concentration testing on admission to hospital. Absence of national guidelines on blood alcohol testing in the emergency department compounds the problem.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Accidentes de Tránsito/estadística & datos numéricos , Consumo de Bebidas Alcohólicas/efectos adversos , Lesiones Encefálicas/epidemiología , Lesiones Encefálicas/etiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Autopsia , Lesiones Encefálicas/mortalidad , Bases de Datos Factuales , Etanol/sangre , Femenino , Humanos , Irlanda/epidemiología , Masculino , Persona de Mediana Edad , Medición de Riesgo , Asunción de Riesgos , Factores Sexuales , Adulto Joven
16.
Clin Lab Haematol ; 27(3): 190-4, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15938725

RESUMEN

This study assesses the impact of permitting unrestricted access to requests for soluble transferrin receptor (sTfR) analysis in screening for iron deficiency (ID). Biochemical data including sTfR, serum ferritin (sFn), transferrin saturation, zinc protoporphyrins (ZPP) and also erythrocyte indices are used to highlight the differences between hospital (H) and general practitioner (GP) patient groups. A significantly higher number of abnormal sFn values (40%) over abnormal sTfR values (25%) occurred in GP patients. This trend was reversed in the H patient group where high sTfR values predominated. Consequently, screening with sFn, exclusively, missed ID (sTfR > 28.1 nmol/l) in 5% of GP patients and in 20% of H patients. Some 40% of H patients had elevated CRP values (CRP > 10 mg/l) indicating inflammatory disease, however, ZPP was more efficient than CRP at screening the validity of normal sFn values in the group. Unrestricted access to sTfR, sFn and ZPP analyses should expedite diagnosis in all patients, particularly H patients, but may be costly. The high specificity (>90%) of the mean cell haemoglobin for ID may be under-utilized diagnostically.


Asunto(s)
Anemia Ferropénica/diagnóstico , Receptores de Transferrina/sangre , Anemia Ferropénica/sangre , Biomarcadores/sangre , Diagnóstico Diferencial , Servicios de Diagnóstico/normas , Servicios de Diagnóstico/estadística & datos numéricos , Índices de Eritrocitos , Femenino , Ferritinas/sangre , Humanos , Irlanda , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Protoporfirinas/sangre , Sensibilidad y Especificidad
18.
Colorectal Dis ; 4(2): 111-114, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12780632

RESUMEN

OBJECTIVE: To evaluate the efficiency of the criteria proposed by the National Referral Guidelines at selecting patients with lower gastrointestinal tract cancer for urgent outpatient assessment when compared with the standard method for prioritization. PATIENTS AND METHODS: Consecutive patients aged 50 and over referred to a colorectal unit were offered urgent or non-urgent outpatient appointments on the basis of the contents of the referral letter. Clinical information obtained during the outpatient consultation was used to identify those patients that satisfied the guideline criteria for urgent referral. Patients were investigated and the findings recorded. RESULTS: Of 247 patients who completed their investigations 18 were found to have lower gastrointestinal tract cancer. Urgent outpatient appointments were offered to 115 patients of whom 14 had cancer (P = 0.0067, sensitivity=78%). A total of 119 patients satisfied the guideline criteria for urgent referral, including 17 of the patients who were found to have cancer (P < 0.0001, sensitivity=94%). CONCLUSION: The criteria used in the guidelines provide an effective method for selecting patients with cancer for urgent assessment. Application of the guidelines by general practitioners can be recommended.

19.
J Biol Chem ; 274(49): 34961-6, 1999 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-10574972

RESUMEN

The influence of mRNA localization on metallothionein-1 protein distribution was studied by immunocytochemistry. We used Chinese hamster ovary cells that had been transfected with either a native metallothionein-1 gene construct or metallothionein-1 5'-untranslated region and coding sequences linked to the 3'-untranslated region from glutathione peroxidase. The change in the 3'-untranslated region caused the delocalization of the mRNA with a loss of the perinuclear localization and association with the cytoskeleton. Clones were selected which expressed similar levels of metallothionein-1 protein, as assessed by radioimmunoassay. The results showed that loss of metallothionein-1 mRNA localization was associated with a loss of metallothionein-1 protein localization, most notably with a lack of metallothionein-1 protein in the nucleus of synchronized cells which were beginning to synthesize DNA. This indicates that the association of metallothionein-1 mRNA with the cytoskeleton around the nucleus is essential for efficient shuttling of the protein into the nucleus during the G(1) to S phase transition. This is the first demonstration of a physiological role for perinuclear mRNA localization and we propose that such localization may be important for a wide range of nuclear proteins, including those that shuttle between nucleus and cytoplasm in a cell cycle dependent manner.


Asunto(s)
Núcleo Celular/metabolismo , Citoesqueleto/metabolismo , Metalotioneína/metabolismo , ARN Mensajero/metabolismo , Regiones no Traducidas 3'/genética , Animales , Transporte Biológico , Células CHO , Ciclo Celular , Núcleo Celular/genética , Cricetinae , Citoplasma/metabolismo , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/metabolismo , Inmunohistoquímica , Metalotioneína/genética , Microscopía Confocal , Fase S , Timidina/metabolismo , Factores de Tiempo , Transfección
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