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1.
Ann Bot ; 127(4): 397-410, 2021 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-33507251

RESUMEN

BACKGROUND: Investigating the causes and consequences of intraspecific trait variation (ITV) in plants is not novel, as it has long been recognized that such variation shapes biotic and abiotic interactions. While evolutionary and population biology have extensively investigated ITV, only in the last 10 years has interest in ITV surged within community and comparative ecology. SCOPE: Despite this recent interest, still lacking are thorough descriptions of ITV's extent, the spatial and temporal structure of ITV, and stronger connections between ITV and community and ecosystem properties. Our primary aim in this review is to synthesize the recent literature and ask: (1) How extensive is intraspecific variation in traits across scales, and what underlying mechanisms drive this variation? (2) How does this variation impact higher-order ecological processes (e.g. population dynamics, community assembly, invasion, ecosystem productivity)? (3) What are the consequences of ignoring ITV and how can these be mitigated? and (4) What are the most pressing research questions, and how can current practices be modified to suit our research needs? Our secondary aim is to target diverse and underrepresented traits and plant organs, including anatomy, wood, roots, hydraulics, reproduction and secondary chemistry. In addressing these aims, we showcase papers from the Special Issue. CONCLUSIONS: Plant ITV plays a key role in determining individual and population performance, species interactions, community structure and assembly, and ecosystem properties. Its extent varies widely across species, traits and environments, and it remains difficult to develop a predictive model for ITV that is broadly applicable. Systematically characterizing the sources (e.g. ontogeny, population differences) of ITV will be a vital step forward towards identifying generalities and the underlying mechanisms that shape ITV. While the use of species means to link traits to higher-order processes may be appropriate in many cases, such approaches can obscure potentially meaningful variation. We urge the reporting of individual replicates and population means in online data repositories, a greater consideration of the mechanisms that enhance and constrain ITV's extent, and studies that span sub-disciplines.


Asunto(s)
Ecosistema , Plantas , Evolución Biológica , Fenotipo , Plantas/genética
2.
Orthod Craniofac Res ; 20 Suppl 1: 12-17, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28643920

RESUMEN

OBJECTIVES: Recurrence of cranial bone fusion following surgical resection in craniosynostosis patients commonly requires additional surgical procedures. Surgical implantation of engineered 3D scaffolds that control tissue mineralization could be utilized to diminish recurrence of fusion. This study investigated the ability of composite scaffolds to control tissue mineralization when cultured in vitro. SETTING AND SAMPLE POPULATION: Precision-engineered scaffolds with calvarial cells were cultured in vitro at the Department of Orthodontics and Pediatric Dentistry, University of Michigan. MATERIAL & METHODS: Polycaprolactone (PCL) scaffolds were fabricated using a novel precision extrusion deposition technique. Polyethylene glycol (PEG) hydrogel was coated onto select scaffolds to inhibit mineralization. MC3T3E1(C4) calvarial cells were cultured with scaffolds in media containing ascorbate and phosphate to promote osteoblast differentiation and mineralization. Scaffolds were assayed for osteoblast differentiation by alkaline phosphatase assay. Scaffolds were assayed for mineralization by nano-computed tomography (nano-CT) and by von Kossa staining of histologic sections. RESULTS: MC3T3E1(C4) cells differentiated into osteoblasts and formed mineral when cultured on uncoated PCL scaffolds. MC3T3E1(C4) cells were significantly diminished in their ability to differentiate into osteoblasts when cultured on hydrogel-coated scaffold. CONCLUSION: Results of this study indicate that this novel printing technology can be used to fabricate 3D scaffolds to promote and inhibit tissue mineralization in a region-specific manner. Future studies are needed to establish utility of such scaffolds in vivo.


Asunto(s)
Calcificación Fisiológica/fisiología , Craneosinostosis/cirugía , Osteogénesis/fisiología , Poliésteres/farmacología , Andamios del Tejido/química , Fosfatasa Alcalina/metabolismo , Diferenciación Celular , Materiales Biocompatibles Revestidos/farmacología , Humanos , Técnicas In Vitro , Nanotecnología , Osteoblastos/citología , Polietilenglicoles/farmacología , Cráneo/citología , Cráneo/cirugía , Propiedades de Superficie , Microtomografía por Rayos X
3.
J Hum Nutr Diet ; 30(4): 524-533, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28211112

RESUMEN

BACKGROUND: Price promotions are a promising intervention for encouraging healthier food purchasing. We aimed to assess the impact of a targeted direct marketing price promotion combined with healthy eating advice and recipe suggestions on the purchase of selected healthier foods by low income consumers. METHODS: We conducted a randomised controlled trial (n = 53 367) of a direct marketing price promotion (Buywell) combined with healthy eating advice and recipe suggestions for low income consumers identified as 'less healthy' shoppers. Impact was assessed using electronic point of sale data for UK low income shoppers before, during and after the promotion. RESULTS: The proportion of customers buying promoted products in the intervention month increased by between 1.4% and 2.8% for four of the five products. There was significantly higher uptake in the promotion month (P < 0.001) for the intervention group than would have been expected on the basis of average uptake in the other months. When product switching was examined for semi-skimmed/skimmed milk, a modest increase (1%) was found in the intervention month of customers switching from full-fat to low-fat milk. This represented 8% of customers who previously bought only full-fat milk. The effects were generally not sustained after the promotion period. CONCLUSIONS: Short-term direct marketing price promotions combined with healthy eating advice and recipe suggestions targeted at low income consumers are feasible and can have a modest impact on short-term food-purchasing behaviour, although further approaches are needed to help sustain these changes.


Asunto(s)
Comercio/economía , Comportamiento del Consumidor , Alimentos/economía , Mercadotecnía/economía , Pobreza , Adulto , Anciano , Dieta Saludable/economía , Estudios de Factibilidad , Femenino , Grupos Focales , Humanos , Persona de Mediana Edad , Reino Unido
4.
J Gambl Stud ; 33(4): 1241-1260, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28421402

RESUMEN

Near misses and losses disguised as wins have been of interest to gambling researchers and policymakers for many years (e.g., Griffiths in J Gambl Stud 9(2):101-120, 1993). This systematic literature review describes the behavioural, psychological, and psychobiological effects of near misses and losses disguised as wins (LDWs) in an effort to evaluate their precise influence on the player and to highlight areas requiring further investigation. A systematic search for relevant studies was conducted using Scopus, PubMed, PsycINFO, ProQuest Sociology databases, and the Gambling Research Exchange Ontario Knowledge Repository. A total of 51 (from an initial pool of 802) experimental peer-reviewed studies using human participants were found between 1991 and 2015. The systematic review revealed that near misses motivate continued play, but have varying effects on the emotional state or betting behaviour of the player. Near miss events were also shown to be associated with elevated skin conductance levels and diffuse activity across the brain, most consistently in areas processing reinforcement and reward. Re-examination of the studies of near misses events after classifying the type of game feedback suggested that the effectiveness of near misses is related to the phenomenology of a near miss itself rather than as a response to auditory or visual feedback provided by a slot machine. In contrast to near misses, the presence of LDWs was found to relate to an overestimation of how much a player is actually winning and was consistently viewed as an exciting event. The effect of LDWs appears to be driven by the presence of visuals and sounds most often associated with a true win. Practical implications and directions for future research are also discussed.


Asunto(s)
Ansiedad/psicología , Conducta Adictiva/psicología , Juego de Azar/psicología , Recompensa , Juegos de Video/psicología , Adulto , Emociones , Femenino , Humanos , Internet , Masculino , Motivación , Autoinforme , Encuestas y Cuestionarios
5.
J Viral Hepat ; 23(7): 561-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26940754

RESUMEN

Assiduous measures are taken to prevent perinatal transmission of hepatitis B virus (HBV) to infants; it is unclear whether the mothers receive appropriate care for their chronic HBV. We sought to assess the quality of HBV care in hepatitis B surface antigen (HBsAg)-positive mothers following pregnancy. HBsAg-positive women (n = 243) who had sought prenatal care at Massachusetts General Hospital were retrospectively identified and charts reviewed. The primary outcome was adherence to the American Association for the Study of Liver Diseases (AASLD) and American College of Obstetricians and Gynecologists guidelines. Over one-third (37%) of women were first diagnosed with HBV infection at a prenatal visit. One-third (32%) did not undergo timely liver function test measurements. HBV DNA was never measured in 26% and was untimely in 34% of patients. One-third (34%) of the women were at high-risk for HCC based on AASLD criteria, yet only 33% of these women underwent timely imaging. Nearly half (49%) never saw a liver specialist for their HBV care. In multivariate analysis, women were 3.7 times more likely to have a timely ALT and 8.1 times more likely to have a timely HBV DNA if they were followed by a liver specialist (P = 0.001, <0.001). We demonstrate remarkably inadequate and discontinuous HBV care for chronically infected mothers following pregnancy. As HBV infection is already being identified prenatally, quality improvement measures encompassing obstetricians, primary care providers and hepatologists are needed to ensure that HBV-infected women are linked to care postpregnancy.


Asunto(s)
Investigación sobre Servicios de Salud , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/terapia , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/terapia , Adulto , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/transmisión , Humanos , Massachusetts , Persona de Mediana Edad , Embarazo , Estudios Retrospectivos , Adulto Joven
6.
J Microsc ; 263(2): 148-57, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26820914

RESUMEN

Optical highlighters comprise photo-activatable, photo-switchable and photo-convertible fluorescent proteins and are relatively recent additions to the toolbox utilized for live cell imaging research. Here, we provide an overview of four photo-convertible fluorescent proteins (pcFP) that are being used in plant cell research: Eos, Kaede, Maple and Dendra2. Each of these proteins has a significant advantage over other optical highlighters since their green fluorescent nonconverted forms and red fluorescent converted forms are generally clearly visible at expression levels that do not appear to interfere with subcellular dynamics and plant development. These proteins have become increasingly useful for understanding the role of transient and sustained interactions between similar organelles. Tracking of single organelles after green-to-red conversion has provided novel insights on plastids and their stroma-filled extensions and on the formation of mega-mitochondria. Similarly colour recovery after photo-conversion has permitted the estimation of nuclear endo-reduplication events and is being developed further to image protein trafficking within the lumen of the endoplasmic reticulum. We have also applied photo-convertible proteins to create colour-differentiation between similar cell types to follow their development. Both the green and red fluorescent forms of these proteins are compatible with other commonly used single coloured FPs. This has allowed us to develop simultaneous visualization schemes for up to five types of organelles and investigate organelle interactivity. The advantages and caveats associated with the use of photo-convertible fluorescent proteins are discussed.


Asunto(s)
Espacio Intracelular/metabolismo , Proteínas Luminiscentes/metabolismo , Proteínas Luminiscentes/efectos de la radiación , Células Vegetales/metabolismo , Color , Retículo Endoplásmico/metabolismo , Proteínas Luminiscentes/análisis , Mitocondrias/metabolismo , Plastidios/metabolismo , Transporte de Proteínas
7.
J Hum Nutr Diet ; 28(2): 126-34, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24588787

RESUMEN

BACKGROUND: Energy density (ED) is a measure of the energy content of a food component or diet relative to a standard unit of weight. Widespread variation in ED assessment methodologies exist. The present study aimed to explore the feasibility of calculating the ED of the Scottish diet using UK food purchase survey data and to identify the most appropriate method for calculating ED for use in the development of a Scottish Dietary Goal that captures any socioeconomic differences. METHODS: Energy density was calculated using five different methods [food; food and milk; food, milk and energy containing (non-alcoholic) beverages; food, milk and all non-alcoholic beverages; and all food and beverages]. ED of the Scottish diet was estimated for each of the ED methods and data were examined by deprivation category. RESULTS: Mean ED varied from 409 to 847 kJ 100 g(-1) depending on the method used. ED values calculated from food (847 kJ 100 g(-1) ) and food and milk (718 kJ 100 g(-1) ) were most comparable to other published data, with the latter being a more accurate reflection of all food consumed. For these two methods, there was a significant gradient between the most and least deprived quintiles (892-807 and 737-696 kJ 100 g(-1) for food and food and milk, respectively). CONCLUSIONS: Because the World Cancer Research Fund recommendations are based on ED from food and milk, it was considered prudent to use this method for policy purposes and for future monitoring work of the Scottish Diet to ensure consistency of reporting and comparability with other published studies.


Asunto(s)
Ingestión de Energía , Preferencias Alimentarias , Alimentos , Animales , Bebidas/análisis , Dieta , Análisis de los Alimentos , Humanos , Leche/química , Política Nutricional , Escocia , Reino Unido
8.
Proc Biol Sci ; 281(1778): 20132851, 2014 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-24452023

RESUMEN

Dispersal is not a blind process, and evidence is accumulating that individual dispersal strategies are informed in most, if not all, organisms. The acquisition and use of information are traits that may evolve across space and time as a function of the balance between costs and benefits of informed dispersal. If information is available, individuals can potentially use it in making better decisions, thereby increasing their fitness. However, prospecting for and using information probably entail costs that may constrain the evolution of informed dispersal, potentially with population-level consequences. By using individual-based, spatially explicit simulations, we detected clear coevolutionary dynamics between prospecting and dispersal movement strategies that differed in sign and magnitude depending on their respective costs. More specifically, we found that informed dispersal strategies evolve when the costs of information acquisition during prospecting are low but only if there are mortality costs associated with dispersal movements. That is, selection favours informed dispersal strategies when the acquisition and use processes themselves were not too expensive. When non-informed dispersal strategies evolve, they do so jointly with the evolution of long dispersal distance because this maximizes the sampling area. In some cases, selection produces dispersal rules different from those that would be 'optimal' (i.e. the best possible population performance--in our context quantitatively measured as population density and patch occupancy--among all possible individual movement rules) for the population. That is, on the one hand, informed dispersal strategies led to population performance below its highest possible level. On the other hand, un- and poorly informed individuals nearly optimized population performance, both in terms of density and patch occupancy.


Asunto(s)
Distribución Animal , Evolución Biológica , Modelos Teóricos , Selección Genética , Animales , Ecosistema , Extinción Biológica , Dinámica Poblacional
9.
Gene Ther ; 20(12): 1131-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23842593

RESUMEN

Oncolytic adenovirus-mediated suicide gene therapy has been shown to improve local tumor control in preclinical tumor models and in the clinic. Although local tumor control is important, for most human cancers, new therapies must also target metastatic disease if they are to have an impact on survival. Here, we test the hypothesis that adding cytokine gene therapy to our multimodal platform improves both local and metastatic tumor control in a preclinical model of prostate cancer. An oncolytic adenovirus (Ad5-yCD/mutTKSR39rep-mIL12) expressing two suicide genes and mouse interleukin-12 (IL-12) was generated. Relative to an adenovirus lacking IL-12 (Ad5-yCD/mutTKSR39rep), Ad5-yCD/mutTKSR39rep-mIL12 improved local and metastatic tumor control in the TRAMP-C2 prostate adenocarcinoma model, resulting in a significant increase in survival. Ad5-yCD/mutTKSR39rep-mIL12 resulted in high levels of IL-12 and interferon gamma in serum and tumor, increased natural killer (NK) and cytotoxic T-lymphocyte lytic activities, and the development of tumor-specific antitumor immunity. Immune cell depletion studies indicated that both the innate and adaptive arms of immunity were required for maximal Ad5-yCD/mutTKSR39rep-mIL12 activity. The results demonstrate that the addition of IL-12 significantly improves the efficacy of oncolytic adenovirus-mediated suicide gene therapy and provide the scientific basis for future trials targeting locally aggressive cancers.


Asunto(s)
Adenoviridae/genética , Genes Transgénicos Suicidas , Terapia Genética , Interleucina-12/genética , Virus Oncolíticos/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/terapia , Animales , Línea Celular Tumoral , Terapia Combinada , Expresión Génica , Vectores Genéticos , Humanos , Interferón gamma/sangre , Células Asesinas Naturales/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Metástasis de la Neoplasia/genética , Metástasis de la Neoplasia/terapia , Viroterapia Oncolítica , Neoplasias de la Próstata/inmunología , Linfocitos T Citotóxicos/inmunología
10.
Proc Biol Sci ; 279(1731): 1194-202, 2012 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-21957132

RESUMEN

The movement rules used by an individual determine both its survival and dispersal success. Here, we develop a simple model that links inter-patch movement behaviour with population dynamics in order to explore how individual dispersal behaviour influences not only its dispersal and survival, but also the population's rate of range expansion. Whereas dispersers are most likely to survive when they follow nearly straight lines and rapidly orient movement towards a non-natal patch, the most rapid rates of range expansion are obtained for trajectories in which individuals delay biasing their movement towards a non-natal patch. This result is robust to the spatial structure of the landscape. Importantly, in a set of evolutionary simulations, we also demonstrate that the movement strategy that evolves at an expanding front is much closer to that maximizing the rate of range expansion than that which maximizes the survival of dispersers. Our results suggest that if one of our conservation goals is the facilitation of range-shifting, then current indices of connectivity need to be complemented by the development and utilization of new indices providing a measure of the ease with which a species spreads across a landscape.


Asunto(s)
Fenómenos de Retorno al Lugar Habitual , Modelos Biológicos , Animales , Conservación de los Recursos Naturales , Densidad de Población , Dinámica Poblacional
12.
Acta Theriol (Warsz) ; 57(3): 205-216, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22707756

RESUMEN

Cyclic population dynamics of small mammals are not restricted to the boreal and arctic zones of Eurasia and North America, but long-term data series from lower latitudes are still less common. We demonstrated here the presence of periodic oscillations in small mammal populations in eastern Poland using 22-year (1986-2007) trapping data from marginal meadow and river valley grasslands located in the extensive temperate woodland of Bialowieza Primeval Forest. The two most common species inhabiting meadows and river valleys, root vole Microtus oeconomus and common shrew Sorex araneus, exhibited synchronous periodic changes, characterised by a 3-year time lag as indicated by an autocorrelation function. Moreover, the cycles of these two species were synchronous within both habitats. Population dynamics of the striped field mouse Apodemus agrarius was not cyclic. However, this species regularly reached maximum density 1 year before the synchronized peak of root voles and common shrews, which may suggest the existence of interspecific competition. Dynamics of all three species was dominated by direct density-dependent process, whereas delayed density dependent feedback was significant only in the root vole and common shrew. Climatic factors acting in winter and spring (affecting mainly survival and initial reproduction rates) were more important than those acting in summer and autumn and affected significantly only the common shrew. High temperatures in winter and spring had positive effects on autumn-to-autumn changes in abundance of this species, whereas deep snow in combination with high rainfall in spring negatively affected population increase rates in common shrew.

13.
Curr Eye Res ; 47(12): 1567-1577, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36214781

RESUMEN

PURPOSE: People of African Caribbean Descent (ACD) have a higher prevalence of glaucoma compared to people of European Descent (ED) and there is uncertainty if treatment outcomes are equivalent between the two groups. To assess surgical failure rates comparing ACD with ED focusing on trabeculectomy, aqueous shunt implantation, non-penetrating filtering surgery (NPFS), and minimally invasive glaucoma surgery (MIGS) by performing a systematic review in accordance with the PRISMA guidelines and to determine whether there is any evidence in to show a difference in success rates based on race. METHODS: A systematic review of articles using the CENTRAL, Ovid MEDLINE, PubMed, EMBASE, and ClinicalTrials.gov databases was completed. Additional studies were identified by contacting clinical experts and searching bibliographies. All retrospective and prospective studies on trabeculectomy, aqueous shunt implantation, NPFS, and MIGS that included at least 20% ACD were included. Two review authors independently screened search results for eligibility and inclusion and extracted the data using pre-determined fields. RESULTS: A total of 76 studies were identified for inclusion in the review. Glaucoma surgical outcomes in ACD appear to be poorer compared to ED overall, particularly for trabeculectomy. Data on NPFS are limited, but the studies completed thus far demonstrate surprisingly good results for ACD, particularly when compared to ED, who have significantly lower pre-operative IOPs. Evidence from studies investigating aqueous shunts does not suggest that ACD have poorer outcomes than ED. There is not enough data on MIGS to provide a significant conclusion. CONCLUSION: In a population where trabeculectomy may no longer be the gold standard, sufficiently powered studies assessing surgical outcomes in aqueous shunts, NPFS, and MIGS are needed to guide clinicians.


Asunto(s)
Glaucoma , Trabeculectomía , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Trabeculectomía/métodos , Glaucoma/cirugía , Glaucoma/tratamiento farmacológico , Resultado del Tratamiento , Región del Caribe/epidemiología , Presión Intraocular
14.
J Orthop Res ; 40(4): 838-845, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34061360

RESUMEN

Posttraumatic osteoarthritis (PTOA) can develop after an injury to the knee. Previous studies have indicated that an intra-articular (IA) injection of the potent glucocorticoid dexamethasone (DEX) may significantly prevent induction of PTOA. The aim of the present study was to investigate the effectiveness of a single IA injection of hyaluronic acid (HA), alone and in combination with DEX following a localized intra-articular injury as a PTOA-preventing treatment option. An established rabbit model of surgical injury consisting of dual intra-articular (IA) drill holes in a non-cartilaginous area of the femoral notch near the origin of the anterior cruciate ligament (ACL) to allow for bleeding into the joint space was used. Immediately following surgery, subjects were treated with HA, HA + DEX, or received no treatment. An uninjured control group was used for comparison (N = 5/group). Rabbits were sacrificed and investigated at 9 weeks post-injury. At 9 weeks post-injury, there was a significant protective capacity of the single IA treatment of DEX + HA on the histological grade of the synovial tissue, and some variable location-specific effects of HA alone and HA + DEX interactions on cartilage damage. Thus, it is possible that co-treatment with HA may interfere with the effectiveness of the DEX. In vitro friction testing indicated that DEX did not interfere with the lubricating ability of HA or synovial fluid on cartilage. These results suggest that a single IA administration of HA in combination with DEX following an IA injury is not recommended for inhibition of PTOA progression in this model.


Asunto(s)
Cartílago Articular , Osteoartritis , Animales , Cartílago/patología , Cartílago Articular/patología , Dexametasona , Humanos , Ácido Hialurónico/farmacología , Inyecciones Intraarticulares , Articulación de la Rodilla/patología , Osteoartritis/patología , Conejos , Rodilla de Cuadrúpedos/patología , Rodilla de Cuadrúpedos/cirugía
16.
J Hum Nutr Diet ; 24(6): 588-95, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21649746

RESUMEN

BACKGROUND: Food skills programmes are widely used as a means to improve confidence in food preparation, the use of basic food skills and food selections amongst low income communities. However, the impact of such interventions are rarely evaluated as a result of a lack of validated assessment tools appropriate for use within this target group. METHODS: A two-page questionnaire utilising a closed-question format was designed based on key domains known to be influenced by cooking skills programmes. Content validity was assessed by a panel of public health experts and face validity by individuals, typical of those who may attend cooking skills classes. Internal and repeat reliability were assessed with groups of adults attending community-based classes. The feasibility of using the tool in community settings was also assessed. RESULTS: The draft questionnaire was amended as appropriate subsequent to content and face validity testing. Cronbach's alpha for confidence and knowledge sections was 0.86 and 0.84, respectively, indicating good internal consistency. Spearman correlation coefficients for repeat reliability testing between time 1 and time 2 for each item were in the range 0.46-0.91 (all significant at P < 0.001), indicating that the questionnaire elicited stable responses for repeated use. Feasibility testing highlighted the need for detailed instructions for course tutors on how to distribute and check questionnaires for completion. CONCLUSIONS: This tool provides a standardised method of evaluating cooking skills interventions that could be utilised in the development and evaluation of multicentre cooking skills interventions.


Asunto(s)
Culinaria , Encuestas y Cuestionarios , Adulto , Anciano , Estudios de Factibilidad , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Pobreza , Salud Pública , Adulto Joven
17.
Science ; 219(4585): 671-82, 1983 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-6297007

RESUMEN

The functional expression of a novel gene in a genetically engineered plant has not yet been reported. One major barrier in movement toward this goal is our limited understanding of the molecular bases of gene expression. Attempts to establish genetic engineering as a practical facet of plant breeding are also complicated by the fact that genes for most important plant characteristics have not yet been identified. However, the benefits to be gained from all aspects of plant improvement are stimulating research into both the development of plant transformation technology and the isolation and characterization of genes responsible for valuable traits. As scientists develop greater knowledge of plant molecular genetics, we can expect to see practical applications in such diverse areas as improvement of plant nutritional quality, decreases in fertilization requirements, and increases in resistance to environmental stresses and pathogens.


Asunto(s)
Agricultura , Ingeniería Genética , Plantas/genética , Vectores Genéticos , Fijación del Nitrógeno , Fotosíntesis , Enfermedades de las Plantas , Proteínas de Plantas/genética
18.
Colorectal Dis ; 11(6): 613-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18624818

RESUMEN

OBJECTIVE: Hypomagnesemia has been shown to have several clinically important sequelae. The aims of this study were: to assess the impact of bowel preparation, with sodium picosulphate (Picolax), on plasma electrolytes, with particular regard to plasma magnesium, in patients undergoing bowel preparation for colonoscopy and colorectal resection and to evaluate the influence of perioperative magnesium levels on postoperative cardiac dysrhythmias. METHOD: Sixty-one patients receiving sodium picosulphate (Picolax) bowel preparation were studied in two groups: Colonoscopy (31 patients) and Colorectal resection (30 patients). Plasma sodium, potassium, magnesium, calcium, urea, creatinine and blood haematocrit were measured in all patients prior to commencement of bowel preparation, at the time of colonoscopy or colorectal resection and 24 h postoperatively (surgery group only). Mean electrolyte and haematocrit levels were then compared. Postoperative cardiac dysrhythmias were recorded and analysed. RESULTS: No significant changes following bowel preparation were observed in plasma sodium, potassium, calcium or creatinine. Plasma urea fell following bowel preparation (colonoscopy P < 0.001, resection P = 0.004) and rose following resection (P = 0.002). Magnesium levels increased following bowel preparation in both groups (colonoscopy P < 0.001, resection P = 0.007) and fell following resection (P < 0.001). Thirty-four per cent (21/60 patients) were hypermagnesemic following bowel preparation and 20% (6/30 patients) became hypomagnesemic following surgery. Postoperative cardiac dysrhythmias were associated with lower magnesium levels at induction and postoperatively (P = 0.022 and P = 0.033). CONCLUSION: Bowel preparation with Picolax does not appear to cause significant electrolyte disturbance, except in elevating plasma magnesium. Postcolorectal resection plasma magnesium dropped significantly suggesting perioperative monitoring and replacement should be routine following colorectal surgery.


Asunto(s)
Fibrilación Atrial/etiología , Catárticos/efectos adversos , Colon/cirugía , Magnesio/sangre , Picolinas/efectos adversos , Cuidados Preoperatorios/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Citratos , Colonoscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos , Cuidados Posoperatorios , Estudios Prospectivos , Desequilibrio Hidroelectrolítico/sangre , Desequilibrio Hidroelectrolítico/inducido químicamente
19.
Colorectal Dis ; 10(2): 157-64, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17477849

RESUMEN

OBJECTIVE: An adequate lymph node harvest is necessary for accurate Dukes' stage discrimination in colorectal cancer. The aim of this study is to identify the effect of variables, including the individual surgeon and pathologist, on lymph node harvest in a single institution. METHOD: Three hundred and eighty one consecutive patients had resection for colorectal cancer, in a single unit. Factors influencing lymph node retrieval, including individual surgeon and reporting pathologist, were subjected to uni- and multivariate analysis. Actuarial survival of all patients with Dukes' stage B and C disease was then calculated and survival compared between Dukes' stage B and C at differing levels of lymph node harvest. RESULTS: The unit median lymph node harvest was 13 nodes/patient (95% CI 13.1-14.5). There was no difference in lymph node harvest between specialist colorectal surgeons and the pooled results of four nonspecialist consultant surgeons. However, there was a significant difference between reporting pathologists (P < 0.001). On univariate analysis, operation type, operative urgency, Dukes' stage, T-stage, reporting pathologist and use of neoadjuvant therapy in rectal cancer, were found to significantly affect lymph node retrieval. On multivariate analysis, operation type, T-stage, reporting pathologist and neoadjuvant therapy in rectal cancer remained significant variables. Patients with one or more lymph node metastasis had greater nodal harvests than those without (median 15 vs 12 P = 0.02). Survival of patients with Dukes' stage B disease was found to improve as lymph node harvest increased. CONCLUSION: Overall lymph node harvest, in this unit, varied according to the reporting pathologist but not operating surgeon. As lymph node harvest increased to 15 per patient, the probability of identifying a metastatic node increased.


Asunto(s)
Adenocarcinoma/patología , Adenocarcinoma/cirugía , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Escisión del Ganglio Linfático , Pautas de la Práctica en Medicina/estadística & datos numéricos , Distribución de Chi-Cuadrado , Femenino , Humanos , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Estudios Prospectivos , Análisis de Regresión , Estadísticas no Paramétricas , Tasa de Supervivencia
20.
J Hum Nutr Diet ; 21(6): 539-46, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18759955

RESUMEN

BACKGROUND: Increasing intakes of dietary antioxidants may help to reduce oxidative damage caused by free radicals and provide protection against the progression of a number of chronic diseases. The present study aimed to estimate the antioxidant intake from fruits and vegetables in the UK and Scottish population and to examine consumption models to identify potential strategies to optimize antioxidant intake from these foods. METHODS: This was a retrospective study of cross-sectional data on fruit and vegetable intake in relation to antioxidant intake. Antioxidant capacity of individual fruits and vegetables was determined by the ferric reducing antioxidant power assay and data on quantity and frequency of consumption of fruits and vegetables determined from National Diet and Nutrition Survey 2000-2001. RESULTS: Mean antioxidant intake in UK population from fruits and vegetables varied by region. In the Scottish sample (n = 123), mean antioxidant intake was estimated at 680 +/- 689 micromol day(-1) with 92% subjects consuming <400 g of fruits and vegetables per day. Consumption data showed that strawberries, apples, orange citrus fruits, purple broccoli and cauliflower were the top five sources of antioxidants from fruits and vegetables in the Scottish population. CONCLUSIONS: Appropriate selection of fruits and vegetables would help to achieve a higher antioxidant intake with the potential to produce significant health benefits.


Asunto(s)
Antioxidantes/administración & dosificación , Encuestas sobre Dietas , Frutas/química , Verduras/química , Adulto , Estudios Transversales , Femenino , Depuradores de Radicales Libres , Humanos , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Estudios Retrospectivos , Escocia , Clase Social , Estadísticas no Paramétricas , Reino Unido , Adulto Joven
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