Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 159
Filtrar
1.
J Exp Bot ; 69(13): 3181-3194, 2018 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-29474730

RESUMEN

Following advances in genetics, genomics, and phenotyping, trait selection in breeding is limited by our ability to understand interactions within the plant and with the environment, and to identify traits of most relevance to the target population of environments. We propose an integrated approach that combines insights from crop modelling, physiology, genetics, and breeding to characterize traits valuable for yield gain in the target population of environments, develop relevant high-throughput phenotyping platforms, and identify genetic controls and their value in production environments. This paper uses transpiration efficiency (biomass produced per unit of water used) as an example of a complex trait of interest to illustrate how the approach can guide modelling, phenotyping, and selection in a breeding programme. We believe that this approach, by integrating insights from diverse disciplines, can increase the resource use efficiency of breeding programmes for improving yield gains in target populations of environments.


Asunto(s)
Grano Comestible/genética , Rasgos de la Historia de Vida , Fenotipo , Fitomejoramiento , Modelos Genéticos
2.
BMC Neurol ; 17(1): 92, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28506263

RESUMEN

BACKGROUND: Mindfulness based stress reduction (MBSR) is increasingly being used to improve outcomes such as stress and depression in a range of long-term conditions (LTCs). While systematic reviews on MBSR have taken place for a number of conditions there remains limited information on its impact on individuals with Parkinson's disease (PD). METHODS: Medline, Central, Embase, Amed, CINAHAL were searched in March 2016. These databases were searched using a combination of MeSH subject headings where available and keywords in the title and abstracts. We also searched the reference lists of related reviews. Study quality was assessed based on questions from the Cochrane Collaboration risk of bias tool. RESULTS: Two interventions and three papers with a total of 66 participants were included. The interventions were undertaken in Belgium (n = 27) and the USA (n = 39). One study reported significantly increased grey matter density (GMD) in the brains of the MBSR group compared to the usual care group. Significant improvements were reported in one study for a number of outcomes including PD outcomes, depression, mindfulness, and quality of life indicators. Only one intervention was of reasonable quality and both interventions failed to control for potential confounders in the analysis. Adverse events and reasons for drop-outs were not reported. There was also no reporting on the costs/benefits of the intervention or how they affected health service utilisation. CONCLUSION: This systematic review found limited and inconclusive evidence of the effectiveness of MBSR for PD patients. Both of the included interventions claimed positive effects for PD patients but significant outcomes were often contradicted by other results. Further trials with larger sample sizes, control groups and longer follow-ups are needed before the evidence for MBSR in PD can be conclusively judged.


Asunto(s)
Atención Plena , Enfermedad de Parkinson , Anciano , Bélgica , Depresión , Femenino , Humanos , Masculino , Enfermedad de Parkinson/psicología , Enfermedad de Parkinson/rehabilitación , Enfermedad de Parkinson/terapia , Calidad de Vida , Estados Unidos
4.
J Surg Case Rep ; 2015(3)2015 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-25740905

RESUMEN

Here, we present a case report of a young male who had been travelling in Thailand. The patient sustained a relatively minor trauma to the soft tissue under his left third metatarsal head on a piece of coral reef. He subsequently developed an infected ulcer, which did not heal despite appropriate antibiotic therapy and surgical debridement. Unfortunately, the patient required amputation of the left third toe and metatarsal head due to osteomyelitic destruction. It later transpired that the ulcer was initially ischaemic in nature due to previously undiagnosed and asymptomatic popliteal artery stenosis.

6.
Intern Med J ; 40(7): 512-20, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19460061

RESUMEN

BACKGROUND: Many adults with arthritis do not achieve physical activity levels recommended for good health. This study aimed to identify factors associated with physical activity participation in people with arthritis. METHODS: 1106 out of 8163 adults with self-reported arthritis were identified from the 2003 Obstacles to Action study. Participants were classified as active if they reported 30 min of moderate activity > or = 5 days a week or 20 min of vigorous activity > or = 3 days a week (n = 613), or insufficiently active if they did not (n = 438). Sociodemographic factors, attitudes, self-efficacy, motivators and barriers to being active were analysed. RESULTS: Active people with arthritis had a lower burden of chronic disease than insufficiently active people (18% with three or more chronic medical conditions vs 33%, P < 0.0001). Active participants believed more strongly in the benefits of physical activity, reported higher levels of encouragement from others and had greater overall levels of self-efficacy when compared with the less active participants (P for all <0.0001). Arthritis, fatigue and discomfort were ranked by both groups as the top three barriers. However, the active participants reported lower impact scores for these barriers than the inactive group (P for all <0.0001). These findings persisted after adjusting for occupational status, body mass index and comorbidities. CONCLUSION: Active adults with arthritis have lower levels of chronic disease, greater self-efficacy and fewer psychosocial barriers. Recognition of such barriers and motivators may be useful when designing intervention programmes to help people with arthritis initiate or intensify physical activity participation.


Asunto(s)
Artritis/psicología , Artritis/terapia , Ejercicio Físico/fisiología , Encuestas Epidemiológicas , Actividad Motora/fisiología , Autoeficacia , Adulto , Artritis/fisiopatología , Actitud Frente a la Salud , Enfermedad Crónica , Ejercicio Físico/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Distribución Aleatoria
7.
J Neural Eng ; 4(1): S72-84, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17325419

RESUMEN

The design of high-resolution retinal prostheses presents many unique engineering and biological challenges. Ever smaller electrodes must inject enough charge to stimulate nerve cells, within electrochemically safe voltage limits. Stimulation sites should be placed within an electrode diameter from the target cells to prevent 'blurring' and minimize current. Signals must be delivered wirelessly from an external source to a large number of electrodes, and visual information should, ideally, maintain its natural link to eye movements. Finally, a good system must have a wide range of stimulation currents, external control of image processing and the option of either anodic-first or cathodic-first pulses. This paper discusses these challenges and presents solutions to them for a system based on a photodiode array implant. Video frames are processed and imaged onto the retinal implant by a head-mounted near-to-eye projection system operating at near-infrared wavelengths. Photodiodes convert light into pulsed electric current, with charge injection maximized by applying a common biphasic bias waveform. The resulting prosthesis will provide stimulation with a frame rate of up to 50 Hz in a central 10 degrees visual field, with a full 30 degrees field accessible via eye movements. Pixel sizes are scalable from 100 to 25 microm, corresponding to 640-10,000 pixels on an implant 3 mm in diameter.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Electrodos Implantados , Electrónica Médica/instrumentación , Óptica y Fotónica/instrumentación , Prótesis e Implantes , Enfermedades de la Retina/rehabilitación , Grabación en Video/instrumentación , Animales , Inteligencia Artificial , Terapia por Estimulación Eléctrica/métodos , Análisis de Falla de Equipo , Humanos , Interpretación de Imagen Asistida por Computador/instrumentación , Microelectrodos , Diseño de Prótesis , Retina/cirugía , Terapia Asistida por Computador/instrumentación , Terapia Asistida por Computador/métodos , Grabación en Video/métodos
8.
J Epidemiol Community Health ; 60(11): 917-22, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17053278

RESUMEN

OBJECTIVE: To examine whether the quality of primary care measured by the 2004 contract varies with socioeconomic deprivation. DESIGN: Retrospective analysis of publicly available data, comparing quality indicators used for payment that allow exclusion of patients (payment quality) and indicators based on the care delivered to all patients (delivered quality). SETTING AND PARTICIPANTS: 1024 general practices in Scotland. MAIN OUTCOME MEASURES: Regression coefficients summarising the relationships between deprivation and payment and delivered quality. RESULTS: Little systematic association is found between payment quality and deprivation but, for 17 of the 33 indicators examined, delivered quality falls with increasing deprivation. Absolute differences in delivered quality are small for most simpler process measures, such as recording of smoking status or blood pressure. Greater inequalities are seen for more complex process measures such as diagnostic procedures, some intermediate outcome measures such as glycaemic control in diabetes and measures of treatment such as influenza immunisation. CONCLUSIONS: The exclusions system succeeds in not penalising practices financially for the characteristics of the population they serve, but does not reward the additional work required in deprived areas and contributes to a continuation of the inverse care law. The contract data collected prevent examination of most complex process or treatment measures and this analysis is likely to underestimate the extent of continuing inequalities in care. Broader lessons cannot be drawn on the effect on inequalities of this new set of incentives until changes are made to the way contract data are collected and analysed.


Asunto(s)
Medicina Basada en la Evidencia , Pobreza , Atención Primaria de Salud/normas , Política Pública , Humanos , Práctica de Salud Pública/normas , Control de Calidad , Medicina Estatal/organización & administración , Reino Unido
9.
Scott Med J ; 50(3): 109-13, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16163996

RESUMEN

BACKGROUND: The primary aim of the Platform Project is to maximise the use of routine data for primary care research in Scotland. AIMS: To assess the extent to which routine data is available and has been used in studies on CHD in General Practice research in Scotland. To assess the advantages and limitations of using routine data in this setting. METHODS: Literature review using a variety of databases catalogues and websites, bibliographies of articles retrieved and searching through journals by hand not available electronically. RESULTS: This review has found that the use of routine data in CHD studies in General Practice research in Scotland remains small. There has been little work undertaken which has combined the use of routine data with other research methods. Limitations with routine data exist particularly with regard to risk factors and ethnicity. However, despite such limitations there exists an increasingly extensive range of data, which exists to help explain tends in CHD, which so far has been largely underused.


Asunto(s)
Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/epidemiología , Medicina Familiar y Comunitaria/normas , Evaluación de Resultado en la Atención de Salud , Actitud del Personal de Salud , Enfermedad Coronaria/terapia , Medicina Familiar y Comunitaria/tendencias , Femenino , Encuestas de Atención de la Salud , Investigación sobre Servicios de Salud , Humanos , Masculino , Pautas de la Práctica en Medicina , Medición de Riesgo , Escocia/epidemiología , Resultado del Tratamiento
10.
Clin Diagn Lab Immunol ; 11(6): 1192-3, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15539528

RESUMEN

Hyper-immunoglobulin M (IgM) syndrome (HIGM) is a rare heterogeneous primary immune deficiency. We describe a patient with HIGM characterized by skewed production of serum IgG subclasses and normal somatic hypermutation. This case may represent a subgroup of HIGM type 4 that is characterized by a biased switching to the V-region proximal constant regions.


Asunto(s)
Reordenamiento Génico de Linfocito B/genética , Hipergammaglobulinemia/sangre , Hipergammaglobulinemia/genética , Inmunoglobulina G/sangre , Inmunoglobulina M/genética , Adolescente , Femenino , Humanos , Hipergammaglobulinemia/patología , Regiones Constantes de Inmunoglobulina/genética , Inmunoglobulina M/sangre , Región Variable de Inmunoglobulina/genética , Cadenas mu de Inmunoglobulina/genética
14.
Dev World Bioeth ; 3(1): 77-95, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-14577454

RESUMEN

Steve Biko died in detention in South Africa in 1977. Critical ethical issues are raised both by the conduct of the doctors responsible for Biko's care and by the subsequent response of the medical profession as a whole. Because those issues are relevant to all healthcare professionals everywhere, the Biko affair provides a useful case study in medical ethics. We discuss the case in this article, describing how we use it in our teaching.


Asunto(s)
Población Negra , Lesiones Encefálicas/terapia , Complicidad , Ética Médica/educación , Atención al Paciente/ética , Atención al Paciente/normas , Médicos , Prisioneros , Mala Conducta Profesional , Tortura , Historia del Siglo XX , Derechos Humanos , Humanos , Rol del Médico , Prejuicio , Calidad de la Atención de Salud , Sociedades Médicas/ética , Sudáfrica
15.
Br J Oral Maxillofac Surg ; 40(5): 397-405, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12379186

RESUMEN

Fourteen patients or their immediate family were interviewed about their experiences of having either unilateral or bilateral external distraction osteogenesis of the mandible. The patients showed a high level of co-operation with treatment. Six of the 14 patients required repeat distractions, and had been informed and accepted that this was a possibility before the initial distraction. However, patients or their parents expressed some reservations about the extraoral distractors, which prevented them from practising their favourite sport and made them vulnerable to bullying by their friends and colleagues. Patients had moderate pain when the appliances were removed. They all expressed their satisfaction with the results and would recommend this treatment to others. Problems, including speech, eating, pain, and sleeping difficulties, were encountered by patients at all stages of treatment. Of considerable concern was the disruption of education when the child was treated during the school term.


Asunto(s)
Mandíbula/cirugía , Avance Mandibular/instrumentación , Avance Mandibular/psicología , Osteogénesis por Distracción/instrumentación , Osteogénesis por Distracción/psicología , Absentismo , Actividades Cotidianas , Adolescente , Niño , Preescolar , Anomalías Craneofaciales/cirugía , Ingestión de Alimentos , Fijadores Externos/efectos adversos , Femenino , Humanos , Lactante , Masculino , Avance Mandibular/efectos adversos , Osteogénesis por Distracción/efectos adversos , Padres/psicología , Cooperación del Paciente , Satisfacción del Paciente , Trastornos del Sueño-Vigilia/etiología , Trastornos del Habla/etiología , Encuestas y Cuestionarios
16.
Cancer Res ; 61(23): 8385-9, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11731413

RESUMEN

Although focal adhesion kinase (FAK) is elevated in epithelial cancers, it is not known whether FAK expression influences tumor development in vivo. We found that fak +/- heterozygous mice display reduced 7,12-dimethylbenz[a]anthracene-induced papilloma formation that correlates with reduced FAK protein expression in the skin. However, the frequency of malignant conversion of papillomas into carcinomas is indistinguishable in fak +/- mice and their wild-type fak +/+ littermates, most likely because papilloma FAK protein expression is elevated to wild-type levels. We also found that keratinocyte FAK protein expression is important for cellular responses downstream of ras in vitro (monitored by extracellular signal-regulated kinase activation after integrin engagement). Because 7,12-dimethylbenz[a]anthracene induces an activating mutation of H-ras, this provides one possible explanation for suppression of papilloma formation when FAK protein is limiting.


Asunto(s)
Dosificación de Gen , Papiloma/enzimología , Proteínas Tirosina Quinasas/biosíntesis , Neoplasias Cutáneas/enzimología , 9,10-Dimetil-1,2-benzantraceno , Animales , Carcinógenos , Femenino , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Queratinocitos/efectos de los fármacos , Queratinocitos/enzimología , Queratinocitos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Papiloma/inducido químicamente , Papiloma/genética , Proteínas Tirosina Quinasas/genética , Transducción de Señal , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/genética , Proteínas ras/fisiología
17.
Neoplasia ; 3(3): 215-26, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11494115

RESUMEN

Integrins play an important role in tumour progression by influencing cellular responses and matrix-dependent adhesion. However, the regulation of matrix-dependent adhesion assembly in epithelial cells is poorly understood. We have investigated the integrin and signalling requirements of cell-matrix adhesion assembly in colon carcinoma cells after plating on fibronectin. Adhesion assembly in these, and in the adenoma cells from which they were derived, was largely dependent on alpha v beta 6 integrin and required phosphorylation of FAK on tyrosine-397. The rate of fibronectin-induced adhesion assembly and the expression of both alpha v beta 6 integrin and FAK were increased during the adenoma-to-carcinoma transition. The matrix-dependent adhesion assembly process, particularly the final stages of complex protrusion that is required for optimal cell spreading, required the activity of extracellular signal-regulated kinase (ERK). Furthermore, phosphorylated ERK was targeted to newly forming cell--matrix adhesions in the carcinoma cells but not the adenoma cells, and inhibition of FAK--tyrosine-397 phosphorylation or MEK suppressed the appearance of phosphorylated ERK at peripheral sites. In addition, inhibition of MEK--ERK activation blocked the formation of peripheral actin microspikes that were necessary for the protrusive phase of cell-matrix adhesion assembly. Thus, MEK--ERK--dependent peripheral actin re-organization is required for the full development of integrin-induced adhesions and this pathway is stimulated in an in vitro model of colon cancer progression.


Asunto(s)
Adenoma/patología , Antígenos de Neoplasias , Moléculas de Adhesión Celular/fisiología , Neoplasias del Colon/patología , Células Epiteliales/patología , Integrinas/fisiología , Quinasas de Proteína Quinasa Activadas por Mitógenos/fisiología , Proteínas Tirosina Quinasas/fisiología , Actinas/metabolismo , Adenoma/metabolismo , Animales , Moléculas de Adhesión Celular/metabolismo , Línea Celular Transformada , Neoplasias del Colon/metabolismo , Progresión de la Enfermedad , Células Epiteliales/metabolismo , Fibronectinas/metabolismo , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Adhesiones Focales/fisiología , Humanos , Integrinas/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Ratones , Ratones Desnudos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Invasividad Neoplásica , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Células Tumorales Cultivadas , Regulación hacia Arriba
18.
J Biol Chem ; 275(30): 23333-9, 2000 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-10816598

RESUMEN

The non-receptor tyrosine kinase FAK plays a key role at sites of cellular adhesion. It is subject to regulatory tyrosine phosphorylation in response to a variety of stimuli, including integrin engagement after attachment to extracellular matrix, oncogene activation, and growth factor stimulation. Here we use an antibody that specifically recognizes the phosphorylated form of the putative FAK autophosphorylation site, Tyr(397). We demonstrate that FAK phosphorylation induced by integrins during focal adhesion assembly differs from that induced by activation of a temperature-sensitive v-Src, which is associated with focal adhesion turnover and transformation. Specifically, although v-Src induces tyrosine phosphorylation of FAK, there is no detectable phosphorylation of Tyr(397). Moreover, activation of v-Src results in a net decrease in fibronectin-stimulated phosphorylation of Tyr(397), suggesting possible antagonism between v-Src and integrin-induced phosphorylation. Our mutational analysis further indicates that the binding of v-Src to Tyr(397) of FAK in its phosphorylated form, which is normally mediated, at least in part, by the SH2 domain of Src, is not essential for v-Src-induced cell transformation. We conclude that different stimuli can induce phosphorylation of FAK on distinct tyrosine residues, linking specific phosphorylation events to ensuing biological responses.


Asunto(s)
Proteína Oncogénica pp60(v-src)/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Tirosina/metabolismo , Secuencia de Aminoácidos , Animales , Células Cultivadas , Embrión de Pollo , Proteína-Tirosina Quinasas de Adhesión Focal , Datos de Secuencia Molecular , Fosforilación , Unión Proteica
19.
Mol Biol Cell ; 11(1): 51-64, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10637290

RESUMEN

Despite the importance of epithelial cell contacts in determining cell behavior, we still lack a detailed understanding of the assembly and disassembly of intercellular contacts. Here we examined the role of the catalytic activity of the Src family kinases at epithelial cell contacts in vitro. Like E- and P-cadherin, Ca(2+) treatment of normal and tumor-derived human keratinocytes resulted in c-Yes (and c-Src and Fyn), as well as their putative substrate p120(CTN), being recruited to cell-cell contacts. A tyrosine kinase inhibitor with selectivity against the Src family kinases, PD162531, and a dominant-inhibitory c-Src protein that interferes with the catalytic function of the endogenous Src kinases induced cell-cell contact and E-cadherin redistribution, even in low Ca(2+), which does not normally support stable cell-cell adhesion. Time-lapse microscopy demonstrated that Src kinase inhibition induced stabilization of transiently formed intercellular contacts in low Ca(2+). Furthermore, a combination of E- and P-cadherin-specific antibodies suppressed cell-cell contact, indicating cadherin involvement. As a consequence of contact stabilization, normal cells were unable to dissociate from an epithelial sheet formed at high density and repair a wound in vitro, although individual cells were still motile. Thus, cadherin-dependent contacts can be stabilized both by high Ca(2+) and by inhibiting Src activity in low (0.03 mM) Ca(2+) in vitro.


Asunto(s)
Cadherinas/metabolismo , Comunicación Celular , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Actinas/metabolismo , Transporte Biológico , Calcio/metabolismo , Catálisis , Células Cultivadas , Citoesqueleto/metabolismo , Inhibidores Enzimáticos/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Humanos , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Proteínas Proto-Oncogénicas c-fyn , Proteínas Proto-Oncogénicas c-yes , Células Tumorales Cultivadas , Familia-src Quinasas/metabolismo
20.
Mol Immunol ; 37(14): 837-45, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11257305

RESUMEN

We describe the construction of new immunoglobulin (Ig) expression vectors and their use in the production of recombinant chimeric Ig molecules in transfected mammalian cells. The vectors contain the cDNA encoding the constant regions of human (mu, alpha1, gammal, gamma2, gamma3, gamma4, kappa) and murine (mu, gamma2a, kappa) Ig heavy and light chains. Unique restriction sites flanking the Ig variable region allow for replacement of variable regions generated by PCR. The CMV promoter allows for the transfection and expression of Ig in non-lymphoid cells. Distinct drug selection markers for heavy chain and light chain expression vectors allows for sequential or co-transfection of the vectors. We show that secretion of recombinant Ig can reach 1.2 microg/ml per million cells per day for transfected B cells. Replacement of the variable region results in the production of functional Ig retaining antigen specificity.


Asunto(s)
Vectores Genéticos , Inmunoglobulinas/genética , Proteínas Recombinantes/biosíntesis , Animales , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Ligeras de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Inmunoglobulinas/biosíntesis , Ratones , Transfección
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA