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1.
Phys Med ; 125: 104502, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39216313

RESUMEN

PURPOSE: This study aims to evaluate the positioning correction extracted from Intra-fraction Cone Beam (IF-CBCT) images obtained during Stereotactic Body Radiotherapy (SBRT) treatments, and to assess whether its magnitude justifies its acquisition. In addition, the results obtained in lung, liver, and pancreas SBRTs with two deep inspiration breath-hold systems (DIBH), and for prostate with/without ultrasound (US) monitoring were compared. METHODS: 1449 treatments, performed with two linear accelerators (LINACs) were retrospectively analyzed. DIBH were performed either with a spirometry-based device or a surface-guidance system and one LINAC was equipped with US monitoring system for prostate. Significance tests were used to account for differences between units. RESULTS: Group systematic error (M) was approximately -0.7 mm for DIBH treatments in superior-inferior (SI) direction with no difference (p > 0.7) between LINACs. Moreover, there was a SI difference of 0.5 mm for prostate treatments (p = 0.008), in favor of the US monitored one. In anterior-posterior (AP) direction, only liver treatments exhibited differences between LINACs, with the spirometer-based system being 0.8 mm inferior (p = 0.003). M<0.4 mm in left-right (LR) direction was found for all locations and LINACs. The spirometer-based system resulted in lower standard deviation of systematic and random errors in most components and locations, with a greater effect observed in liver SBRTs. CONCLUSIONS: The corrections made with IF-CBCT during SBRT treatments were not negligible. Both DIBH systems were effective in managing respiratory movements. However, the spirometry-based system was slightly more accurate. In addition, US monitoring of the prostate appeared to be useful in reducing target shift.

3.
Proc Natl Acad Sci U S A ; 121(15): e2307525121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38557189

RESUMEN

Changes in climate can alter environmental conditions faster than most species can adapt. A prediction under a warming climate is that species will shift their distributions poleward through time. While many studies focus on range shifts, latitudinal shifts in species' optima can occur without detectable changes in their range. We quantified shifts in latitudinal optima for 209 North American bird species over the last 55 y. The latitudinal optimum (m) for each species in each year was estimated using a bespoke flexible non-linear zero-inflated model of abundance vs. latitude, and the annual shift in m through time was quantified. One-third (70) of the bird species showed a significant shift in their optimum. Overall, mean peak abundances of North American birds have shifted northward, on average, at a rate of 1.5 km per year (±0.58 SE), corresponding to a total distance moved of 82.5 km (±31.9 SE) over the last 55 y. Stronger poleward shifts at the continental scale were linked to key species' traits, including thermal optimum, habitat specialization, and territoriality. Shifts in the western region were larger and less variable than in the eastern region, and they were linked to species' thermal optimum, habitat density preference, and habitat specialization. Individual species' latitudinal shifts were most strongly linked to their estimated thermal optimum, clearly indicating a climate-driven response. Displacement of species from their historically optimal realized niches can have dramatic ecological consequences. Effective conservation must consider within-range abundance shifts. Areas currently deemed "optimal" are unlikely to remain so.


Asunto(s)
Cambio Climático , Clima , Animales , Aves/fisiología , Ecosistema , América del Norte
5.
J Med Internet Res ; 25: e43658, 2023 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-37999957

RESUMEN

There are over 8 million central venous access devices inserted each year, many in patients with chronic conditions who rely on central access for life-preserving therapies. Central venous access device-related complications can be life-threatening and add tens of billions of dollars to health care costs, while their incidence is most likely grossly mis- or underreported by medical institutions. In this communication, we review the challenges that impair retention, exchange, and analysis of data necessary for a meaningful understanding of critical events and outcomes in this clinical domain. The difficulty is not only with data extraction and harmonization from electronic health records, national surveillance systems, or other health information repositories where data might be stored. The problem is that reliable and appropriate data are not recorded, or falsely recorded, at least in part because policy, payment, penalties, proprietary concerns, and workflow burdens discourage completeness and accuracy. We provide a roadmap for the development of health care information systems and infrastructure that address these challenges, framed within the context of research studies that build a framework of standardized terminology, decision support, data capture, and information exchange necessary for the task. This roadmap is embedded in a broader Coordinated Registry Network Learning Community, and facilitated by the Medical Device Epidemiology Network, a Public-Private Partnership sponsored by the US Food and Drug Administration, with the scope of advancing methods, national and international infrastructure, and partnerships needed for the evaluation of medical devices throughout their total life cycle.


Asunto(s)
Costos de la Atención en Salud , Atención Dirigida al Paciente , Humanos , Comunicación , Sistema de Registros
6.
Biol Rev Camb Philos Soc ; 98(4): 1388-1423, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37072381

RESUMEN

Biotic homogenisation is defined as decreasing dissimilarity among ecological assemblages sampled within a given spatial area over time. Biotic differentiation, in turn, is defined as increasing dissimilarity over time. Overall, changes in the spatial dissimilarities among assemblages (termed 'beta diversity') is an increasingly recognised feature of broader biodiversity change in the Anthropocene. Empirical evidence of biotic homogenisation and biotic differentiation remains scattered across different ecosystems. Most meta-analyses quantify the prevalence and direction of change in beta diversity, rather than attempting to identify underlying ecological drivers of such changes. By conceptualising the mechanisms that contribute to decreasing or increasing dissimilarity in the composition of ecological assemblages across space, environmental managers and conservation practitioners can make informed decisions about what interventions may be required to sustain biodiversity and can predict potential biodiversity outcomes of future disturbances. We systematically reviewed and synthesised published empirical evidence for ecological drivers of biotic homogenisation and differentiation across terrestrial, marine, and freshwater realms to derive conceptual models that explain changes in spatial beta diversity. We pursued five key themes in our review: (i) temporal environmental change; (ii) disturbance regime; (iii) connectivity alteration and species redistribution; (iv) habitat change; and (v) biotic and trophic interactions. Our first conceptual model highlights how biotic homogenisation and differentiation can occur as a function of changes in local (alpha) diversity or regional (gamma) diversity, independently of species invasions and losses due to changes in species occurrence among assemblages. Second, the direction and magnitude of change in beta diversity depends on the interaction between spatial variation (patchiness) and temporal variation (synchronicity) of disturbance events. Third, in the context of connectivity and species redistribution, divergent beta diversity outcomes occur as different species have different dispersal characteristics, and the magnitude of beta diversity change associated with species invasions also depends strongly on alpha and gamma diversity prior to species invasion. Fourth, beta diversity is positively linked with spatial environmental variability, such that biotic homogenisation and differentiation occur when environmental heterogeneity decreases or increases, respectively. Fifth, species interactions can influence beta diversity via habitat modification, disease, consumption (trophic dynamics), competition, and by altering ecosystem productivity. Our synthesis highlights the multitude of mechanisms that cause assemblages to be more or less spatially similar in composition (taxonomically, functionally, phylogenetically) through time. We consider that future studies should aim to enhance our collective understanding of ecological systems by clarifying the underlying mechanisms driving homogenisation or differentiation, rather than focusing only on reporting the prevalence and direction of change in beta diversity, per se.


Asunto(s)
Biodiversidad , Ecosistema , Agua Dulce , Modelos Biológicos
7.
8.
Ecol Lett ; 25(12): 2739-2752, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36269686

RESUMEN

Species' responses to broad-scale environmental or spatial gradients are typically unimodal. Current models of species' responses along gradients tend to be overly simplistic (e.g., linear, quadratic or Gaussian GLMs), or are suitably flexible (e.g., splines, GAMs) but lack direct ecologically interpretable parameters. We describe a parametric framework for species-environment non-linear modelling ('senlm'). The framework has two components: (i) a non-linear parametric mathematical function to model the mean species response along a gradient that allows asymmetry, flattening/peakedness or bimodality; and (ii) a statistical error distribution tailored for ecological data types, allowing intrinsic mean-variance relationships and zero-inflation. We demonstrate the utility of this model framework, highlighting the flexibility of a range of possible mean functions and a broad range of potential error distributions, in analyses of fish species' abundances along a depth gradient, and how they change over time and at different latitudes.


Asunto(s)
Ambiente , Dinámicas no Lineales , Animales , Análisis Espacial , Peces
9.
J Dent Res ; 101(13): 1590-1596, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36271667

RESUMEN

Choosing hypodontia treatment requires young people and parents to consider a large amount of information, identify what is important to them, and make trade-offs between options. This study aimed to examine young people and parents' preferences for hypodontia treatment using discrete choice experiment (DCE). This was a cross-sectional survey of young people (12-16 y) with hypodontia of any severity, at any stage of treatment, and their parents. Participants were recruited from NHS Hospitals in England and Wales. A bespoke DCE questionnaire was developed to measure preferences for 6 attributes of hypodontia treatment (waiting time, treatment time, problems during treatment, discomfort during treatment, bite, appearance). The questionnaire was completed 1) online by young people and parents, individually or together, and 2) by child-parent dyads under observation. Preferences were analyzed using regression models. In total, 204 participants (122 young people, 56 parents, 26 dyads) completed the online questionnaire and 15 child-parent dyads completed the questionnaire under observation. The most important attribute in hypodontia treatment was improvement in appearance, but significant heterogeneity was found in preferences. Four distinct groups of participants were found: group 1 (39%): severe discomfort and problems were most important; group 2 (31%): most concerned about improvement in appearance of teeth and improvement in bite; group 3 (22%): appearance 3 times more important than any other attribute; and group 4 (9%): preferences difficult to interpret. There was variation in how child-parent dyads approached decision-making, with some negotiating joint preferences, while for others, one individual dominated. Making trade-offs in DCE tasks helped some people think about treatment and identify their preferences. Appearance is an important outcome from hypodontia treatment, but preferences vary and potential risks and functional outcome are also important to some people. There is a notable level of uncertainty in decision-making, which suggests further shared decision support would be valuable.


Asunto(s)
Anodoncia , Humanos , Adolescente , Anodoncia/terapia , Estudios Transversales , Padres , Encuestas y Cuestionarios , Inglaterra , Prioridad del Paciente
12.
Clin Dermatol ; 40(2): 128-134, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34980507

RESUMEN

Nutrition and dietary supplements are commonly used in the management of psoriasis; however, evidence of their efficacy is inconsistent. Although some dietary interventions have been shown to improve psoriasis consistently, others have little evidence supporting their use. We review common dietary interventions for the management of psoriasis and the evidence behind them. Caloric restriction, especially in overweight and obese individuals, has been shown to consistently diminish psoriatic activity. Evidence about other supplements and dietary interventions is inconsistent. Given the cost and side effects of pharmaceutical treatments for psoriasis, larger, long-term studies on the use of nutrition for the management of psoriasis are necessary.


Asunto(s)
Psoriasis , Dieta , Suplementos Dietéticos , Humanos , Obesidad/complicaciones , Psoriasis/tratamiento farmacológico
14.
Clin Transl Oncol ; 24(3): 532-539, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34585316

RESUMEN

BACKGROUND: Hand osteoarthritis (HOA) is one of the most common causes of pain and functional disability in western countries and there is still no definitive cure. Low-dose radiation therapy (LDRT) has anti-inflammatory properties that have shown to be effective in the symptomatic relief of various degenerative musculoskeletal disorders. We designed a clinical protocol using LDRT for symptomatic HOA and present results and tolerance in the first 100 patients included. MATERIALS AND METHODS: Between April 2015 and March 2021, 100 patients with a median age of 60 were treated. Fifty-seven patients suffering from proximal/distal interphalangeal joint pain, 40 patients with thumb arthritis, 2 patients with radiocarpal joint affection and 1 patient with metacarpophalangeal joint pain were enrolled. LDRT comprised of 6 fractions of 0.5-1 Gy on every other day up to a total dose of 3-6 Gy. Clinical response was evaluated according to the visual analog scale (VAS) for pain level and the von Pannewitz score (VPS) for joint functionality. Any patients not achieving subjective adequate pain relief after 8 weeks of treatment were offered a second identical LDRT course. RESULTS: With a median follow-up of 10.5 months (range 7.55-12.45), 94% reported an improvement in the pain, with a significant reduction in the VAS level after 3, 6 and 12 months (p < 0.001). Sixty-three patients needed a second course of treatment at a median time interval of 12 weeks (range 9-14). The mean VAS score before treatment was 8 (range 3-10). After treatment, it was 5 (range 1-10). After 3, 6 and 12 months, the mean VAS scores were 4 (range 0-9), 3 (range 0-9) and 3.5 (range 0-9), respectively. Seventy patients reported functionality improvements after LDRT according to the von Pannewitz score. No acute or late complications were observed. CONCLUSION: LDRT appears to be safe and useful for HOA and is associated with good rates of pain relief and functionality improvements. However, further studies are necessary to confirm these promising results.


Asunto(s)
Articulaciones de la Mano , Osteoartritis/radioterapia , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosificación Radioterapéutica , Resultado del Tratamiento
15.
Epidemics ; 37: 100521, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34775297

RESUMEN

Understanding the relative contribution of different between-farm transmission pathways is essential in guiding recommendations for mitigating disease spread. This study investigated the association between contact pathways linking poultry farms in New Zealand and the genetic relatedness of antimicrobial resistant Campylobacter jejuni Sequence Type 6964 (ST-6964), with the aim of identifying the most likely contact pathways that contributed to its rapid spread across the industry. Whole-genome sequencing was performed on 167C. jejuni ST-6964 isolates sampled from across 30 New Zealand commercial poultry enterprises. The genetic relatedness between isolates was determined using whole genome multilocus sequence typing (wgMLST). Permutational multivariate analysis of variance and distance-based linear models were used to explore the strength of the relationship between pairwise genetic associations among the C. jejuni isolates and each of several pairwise distance matrices, indicating either the geographical distance between farms or the network distance of transportation vehicles. Overall, a significant association was found between the pairwise genetic relatedness of the C. jejuni isolates and the parent company, the road distance and the network distance of transporting feed vehicles. This result suggests that the transportation of feed within the commercial poultry industry as well as other local contacts between flocks, such as the movements of personnel, may have played a significant role in the spread of C. jejuni. However, further information on the historical contact patterns between farms is needed to fully characterise the risk of these pathways and to understand how they could be targeted to reduce the spread of C. jejuni.


Asunto(s)
Antiinfecciosos , Infecciones por Campylobacter , Campylobacter jejuni , Animales , Infecciones por Campylobacter/epidemiología , Campylobacter jejuni/genética , Pollos , Genotipo , Nueva Zelanda/epidemiología , Aves de Corral
16.
Enferm Intensiva (Engl Ed) ; 32(3): 153-163, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34366295

RESUMEN

INTRODUCTION: Intensive care unit (ICU)-acquired weakness is developed by 40%-46% of patients admitted to ICU. Different studies have shown that Early Mobilisation (EM) is safe, feasible, cost-effective and improves patient outcomes in the short and long term. OBJECTIVE: To design an EM algorithm for the critical patient in general and to list recommendations for EM in specific subpopulations of the critical patient most at risk for mobilisation: neurocritical, traumatic, undergoing continuous renal replacement therapy (CRRT) and with ventricular assist devices (VAD) or extracorporeal membrane oxygenation (ECMO). METHODOLOGY: Review undertaken in the Medline, CINAHL, Cochrane and PEDro databases of studies published in the last 10 years, providing EM protocols/interventions. RESULTS: 30 articles were included. Of these, 21 were on guiding EM in critical patients in general, 7 in neurocritical and/or traumatic patients, 1 on patients undergoing CRRT and 1 on patients with ECMO and/or VAD. Two figures were designed: one for decision-making, taking the ABCDEF bundle into account and the other with the safety criteria and mobility objective for each. CONCLUSIONS: The EM algorithms provided can promote early mobilisation (between the 1st and 5th day from admission to ICU), along with aspects to consider before mobilisation and safety criteria for discontinuing it.


Asunto(s)
Ambulación Precoz , Oxigenación por Membrana Extracorpórea , Algoritmos , Humanos , Unidades de Cuidados Intensivos , Modalidades de Fisioterapia
17.
Ecol Evol ; 11(15): 10600-10612, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34367600

RESUMEN

Variation in both inter- and intraspecific traits affects community dynamics, yet we know little regarding the relative importance of external environmental filters versus internal biotic interactions that shape the functional space of communities along broad-scale environmental gradients, such as latitude, elevation, or depth. We examined changes in several key aspects of functional alpha diversity for marine fishes along depth and latitude gradients by quantifying intra- and interspecific richness, dispersion, and regularity in functional trait space. We derived eight functional traits related to food acquisition and locomotion and calculated seven complementary indices of functional diversity for 144 species of marine ray-finned fishes along large-scale depth (50-1200 m) and latitudinal gradients (29°-51° S) in New Zealand waters. Traits were derived from morphological measurements taken directly from footage obtained using Baited Remote Underwater Stereo-Video systems and museum specimens. We partitioned functional variation into intra- and interspecific components for the first time using a PERMANOVA approach. We also implemented two tree-based diversity metrics in a functional distance-based context for the first time: namely, the variance in pairwise functional distance and the variance in nearest neighbor distance. Functional alpha diversity increased with increasing depth and decreased with increasing latitude. More specifically, the dispersion and mean nearest neighbor distances among species in trait space and intraspecific trait variability all increased with depth, whereas functional hypervolume (richness) was stable across depth. In contrast, functional hypervolume, dispersion, and regularity indices all decreased with increasing latitude; however, intraspecific trait variation increased with latitude, suggesting that intraspecific trait variability becomes increasingly important at higher latitudes. These results suggest that competition within and among species are key processes shaping functional multidimensional space for fishes in the deep sea. Increasing morphological dissimilarity with increasing depth may facilitate niche partitioning to promote coexistence, whereas abiotic filtering may be the dominant process structuring communities with increasing latitude.

19.
J Dairy Sci ; 104(7): 7830-7844, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33865581

RESUMEN

The aim of this study was to evaluate the effects of incorporating rice straw and orange leaves into the diets for goats. Ten Murciano-Granadina goats at mid lactation weighing 45 ± 0.3 kg were used in a crossover design. Two isoproteic and isoenergetic diets (180 g/kg DM and 17 MJ/kg DM, respectively) with alfalfa hay as forage source (33% of DM) were fed. A control diet (CON) incorporated barley as energy source and soy hulls as fiber component. The experimental diet (ORG) replaced barley and soy hulls with orange leaves (19% on DM basis), rice straw (12%, on DM basis) and soya oil (2%). Peas and horsebeans were the protein source in both diets. Each goat received the 2 treatments in 2 periods. Goats were fed the experimental diets and after 14 d on their respective treatments moved to individual metabolism cages for another 7 d. Subsequently, feed intake, total fecal and urine output and milk yield were recorded daily over the first 5 d. During the next 2 d ruminal fluid and blood samples were collected, and then individual gas-exchange measurements were recorded by a mobile open-circuit indirect calorimetry system using a head box. No differences in dry matter intake were detected, and apparent total-tract digestibility was greater in CON than ORG. Efficiency of metabolizable energy intake for milk and maintenance also was lower in response to ORG (0.65 vs. 0.63), with energy balance being negative (-12 kJ/kg of BW0.75) due to mobilization of fat (-16 g/animal vs. 68 g/animal for ORG and CON, respectively). Although actual milk yield was lower in goats fed ORG (2.32 vs. 2.06 kg/d, respectively), energy-corrected milk did not differ (2.81 kg/d on average). In terms of milk quality, milk fat content, and concentrations of monounsaturated (18.54 vs. 11.55 g/100 g milk fat) and polyunsaturated fatty acids (5.75 vs. 3.99 g/100 g milk fat) were greater in goats fed ORG. Based on various indices, the milk produced by ORG would be less atherogenic and thrombogenic than CON milk. Compared with CON, enteric CH4 emission was lower due to feeding ORG (reduction of 38 g CH4/kg milk fat). Data suggest that greater fat mobilization in goats fed ORG might have been due to the apparent lack of synchrony between degradable protein and carbohydrate and the lipogenic nutrients associated with the lower cereal content of the ORG diet. Thus, goats fed ORG seemed to rely more on fat depots to help meet energy requirements and reach optimal performance. As such, the lower content of glucogenic nutrients in ORG did not favor body fat deposition and partitioning of ME into body tissue. Overall, responses in terms of CH4 emissions and milk quality suggest that inclusion of rice straw and orange leaves in diets for small ruminants could be a valuable alternative to reuse, recycle and revalue agricultural by-products.


Asunto(s)
Citrus sinensis , Oryza , Animales , Dieta/veterinaria , Digestión , Femenino , Cabras , Lactancia , Metano , Leche , Nitrógeno , Hojas de la Planta , Rumen
20.
Aust Crit Care ; 34(5): 435-445, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33663950

RESUMEN

BACKGROUND: Intensive care unit-acquired muscle weakness (ICUAW) has an incidence of 40-46%. Early mobilisation is known to be a protective factor. OBJECTIVE: The aim of the study was to identify the incidence of ICUAW in Spain and to evaluate variables likely to contribute to the development of ICUAW. METHODS: A 4-month, prospective observational multicentre cohort study was conducted on patients receiving invasive mechanical ventilation for at least 48 h. Data were collected from ICU day 3 until ICU discharge. The primary outcome was presence of ICUAW (diagnosed using the Medical Research Council [MRC] scale). The secondary outcome was nurse-patient ratio, physiotherapist availability, analgesia, sedation and delirium management, glycaemic control, and daily level of mobility during the ICU stay as per the ICU Mobility Scale. A logistic regression model was constructed based exclusively on days 3-5 of the ICU stay. RESULTS: The data of 642 patients were analysed from 80 ICUs, accounting for 35% of all ICUs in Spain. The incidence of ICUAW was 58% (275 of 474 patients; 95% confidence interval [CI] [53-62]). The predictors for ICUAW were older age (odds ratio [OR] = 1.01; 95% CI [1.00-1.03]) and more days with renal replacement therapy (OR = 1.01; 95% CI [1.00-1.02]). The protective factors for ICUAW were male gender (OR = 0.58; 95% CI [0.38-0.89]), higher Barthel Index (showing prehospital functional independence) (OR = 0.97; 95% CI [0.95-0.99]), more days of being awake and cooperative (defined by a feasible MRC assessment) (OR = 0.98; 95% CI [0.97-0.99]), presence of delirium (OR = 0.98; 95% CI [0.97-0.99]), and more days with active mobilisation (ICU Mobility Scale ≥ 4) (OR = 0.98; 95% CI [0.97-0.99]). CONCLUSIONS: The risk factors for ICUAW were functional dependence before admission, female gender, older age, and more days on renal replacement therapy. The protective factors for ICUAW were feasibility of MRC assessment, the presence of delirium, and being actively mobilised during the first 5 days in the ICU.


Asunto(s)
Unidades de Cuidados Intensivos , Debilidad Muscular , Anciano , Estudios de Cohortes , Femenino , Humanos , Tiempo de Internación , Masculino , Debilidad Muscular/epidemiología , Respiración Artificial
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