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1.
J Cancer Educ ; 38(3): 1091-1097, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37009945

RESUMEN

H igh-quality cancer care is a key priority worldwide. Caring for people affected by cancer requires a range of specific knowledge, skills and experience to deliver the complex care regimens both within the hospital and within the community environment. In June 2022, the European Cancer Organisation along with 33 European cancer societies began working together to develop a curriculum for inter-speciality training for healthcare professionals across Europe. As part of the project, this research consisted of a qualitative survey distributed to the European Union societies via email. The aim of this paper is to disseminate the qualitative findings from healthcare professionals across Europe. Questionnaires were sent out to a convenience sample of 219 healthcare professionals and patient advocates with a response rate of 55% (n = 115). The findings identified that there were four key themes: 'What is inter-speciality training?', 'Barriers and challenges', 'Support throughout the cancer journey' and 'New ways of working'. These results are part of a larger needs analysis and scoping review to inform the development of a core competency framework which will be part of an inter-speciality curriculum for specialist cancer doctors, nurses and other healthcare professionals across Europe. Healthcare professionals will be able to access education and training through the virtual learning environment and workshops and by clinical rotations to other specialties.


Asunto(s)
Curriculum , Neoplasias , Humanos , Personal de Salud/educación , Europa (Continente) , Aprendizaje , Escolaridad , Investigación Cualitativa , Neoplasias/terapia
3.
Dev Cell ; 1(3): 435-40, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11702954

RESUMEN

Development of the arterial pole of the heart is a critical step in cardiogenesis, yet its embryological origin remains obscure. We have analyzed a transgenic mouse line in which beta-galactosidase activity is observed in the embryonic right ventricle and outflow tract of the heart and in contiguous splanchnic and pharyngeal mesoderm. The nlacZ transgene has integrated upstream of the fibroblast growth factor 10 (Fgf10) gene and comparison with the expression pattern of Fgf10 in pharyngeal mesoderm indicates transgene control by Fgf10 regulatory sequences. Dil labeling shows a progressive movement of cells from the pharyngeal arch region into the growing heart tube between embryonic days 8.25 and 10.5. These data suggest that arterial pole myocardium originates outside the classical heart field.


Asunto(s)
Factores de Crecimiento de Fibroblastos/genética , Corazón/embriología , Mesodermo/metabolismo , Faringe/embriología , Animales , Carbocianinas/metabolismo , Factor 10 de Crecimiento de Fibroblastos , Colorantes Fluorescentes/metabolismo , Corazón/fisiología , Hibridación in Situ , Mesodermo/citología , Ratones , Ratones Transgénicos , Miocardio/citología , Miocardio/metabolismo , Faringe/metabolismo , Transgenes , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
4.
J Cell Biol ; 151(6): 1221-34, 2000 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-11121437

RESUMEN

Skeletal muscle is one of a several adult post-mitotic tissues that retain the capacity to regenerate. This relies on a population of quiescent precursors, termed satellite cells. Here we describe two novel markers of quiescent satellite cells: CD34, an established marker of hematopoietic stem cells, and Myf5, the earliest marker of myogenic commitment. CD34(+ve) myoblasts can be detected in proliferating C2C12 cultures. In differentiating cultures, CD34(+ve) cells do not fuse into myotubes, nor express MyoD. Using isolated myofibers as a model of synchronous precursor cell activation, we show that quiescent satellite cells express CD34. An early feature of their activation is alternate splicing followed by complete transcriptional shutdown of CD34. This data implicates CD34 in the maintenance of satellite cell quiescence. In heterozygous Myf5(nlacZ/+) mice, all CD34(+ve) satellite cells also express beta-galactosidase, a marker of activation of Myf5, showing that quiescent satellite cells are committed to myogenesis. All such cells are positive for the accepted satellite cell marker, M-cadherin. We also show that satellite cells can be identified on isolated myofibers of the myosin light chain 3F-nlacZ-2E mouse as those that do not express the transgene. The numbers of satellite cells detected in this way are significantly greater than those identified by the other three markers. We conclude that the expression of CD34, Myf5, and M-cadherin defines quiescent, committed precursors and speculate that the CD34(-ve), Myf5(-ve) minority may be involved in maintaining the lineage-committed majority.


Asunto(s)
Antígenos CD34/aislamiento & purificación , Proteínas de Unión al ADN , Proteínas Musculares/aislamiento & purificación , Músculo Esquelético/citología , Células Madre/citología , Transactivadores , Animales , Diferenciación Celular , Linaje de la Célula , Ratones , Ratones Transgénicos , Fibras Musculares Esqueléticas/citología , Músculo Esquelético/embriología , Factor 5 Regulador Miogénico , Fragmentos de Péptidos/aislamiento & purificación , ARN Mensajero/aislamiento & purificación , Regeneración
5.
Trends Cardiovasc Med ; 9(1-2): 3-10, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10189961

RESUMEN

Differential regulation of cardiac gene expression in vertebrates has been extensively documented in the context of atrial and ventricular morphogenesis. Recent data, largely from the analysis of transgene and endogenous gene expression patterns, have revealed transcriptional differences between left and right cardiac chambers which suggest that the heart is composed of a series of distinct transcriptional domains. Such phenomena provide regional markers (cardiosensors) for the fine analysis of normal and abnormal heart development. Regional subdivisions and transcriptional heterogeneity within the myocardium emerge in response to patterning of the precardiac mesoderm and early heart tube on the anterior-posterior axis, and to embryonic left-right signals which dictate the direction of cardiac looping. Several families of transcription factors have been characterized which may be implicated in the regionalization of myocardial gene expression.


Asunto(s)
Corazón/embriología , Transcripción Genética/genética , Animales , Embrión de Pollo , Regulación del Desarrollo de la Expresión Génica , Marcadores Genéticos/genética , Atrios Cardíacos/embriología , Ventrículos Cardíacos/embriología , Mesodermo/fisiología , Ratones , Ratones Transgénicos/genética , Morfogénesis/genética , Ratas , Factores de Transcripción/genética , Transgenes/genética
6.
Biomaterials ; 6(2): 89-96, 1985 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-4005359

RESUMEN

Recently there has been interest in tests to assess the physiological response to surgical implant corrosion products. Both cell culturing in metal-bearing solutions and intramuscular injection of such solutions have been carried out. This paper examines the effects of the constraints of multicomponent equilibrium conditions on the characteristics of the solutions used in these biocompatibility tests. It is demonstrated that, unbuffered, they will have pH values shifted from neutral and that, in the buffered state, these solutions may contain both dissolved metal ions and insoluble hydroxides. The implications of these characteristics for the interpretation of the results of biocompatibility tests are discussed.


Asunto(s)
Cloruros , Compuestos de Cromo , Metales , Prótesis e Implantes , Animales , Cromo , Cobalto , Corrosión , Técnicas de Cultivo , Compuestos Férricos , Humanos , Concentración de Iones de Hidrógeno , Níquel
7.
Microsc Res Tech ; 50(6): 510-21, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10998640

RESUMEN

Isoform diversity in striated muscle is largely controlled at the level of transcription. In this review we will concentrate on studies concerning transcriptional regulation of the alkali myosin light chain 1F/3F gene. Uncoupled activity of the MLC1F and 3F promoters, together with complex patterns of transcription in developing skeletal and cardiac muscle, combine to make analysis of this gene particularly intriguing. In vitro and transgenic studies of MLC1F/3F regulatory elements have revealed an array of cis-acting modules that each drive a subset of the expression pattern of the two promoters. These cis-acting regulatory modules, including the MLC1F and 3F promoter regions and two skeletal muscle enhancers, control tissue-specificity, cell or fibre-type specificity, and the spatiotemporal regulation of gene expression, including positional information. How each of these regulatory modules acts and how their individual activites are integrated to coordinate transcription at this locus are discussed.


Asunto(s)
Regulación de la Expresión Génica , Variación Genética , Músculo Esquelético/fisiología , Cadenas Ligeras de Miosina/genética , Animales , Secuencia de Bases , Humanos , Datos de Secuencia Molecular , Fibras Musculares Esqueléticas/fisiología , Músculo Esquelético/embriología , Transcripción Genética , Transgenes
8.
Med Phys ; 25(9): 1741-50, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9775382

RESUMEN

In recent years, magnetic-resonance imaging of gelatin doped with the Fricke solution has been applied to the direct measurement of three-dimensional (3D) radiation dose distributions. However, the 3D dose distribution can also be imaged more economically and efficiently using the method of optical absorption computed tomography. This is accomplished by first preparing a gelatin matrix containing a radiochromic dye and mapping the radiation-induced local change in the optical absorption coefficient. Ferrous-Benzoic-Xylenol (FBX) was the dye of choice for this investigation. The complex formed by Fe3+ and xylenol orange exhibits a linear change in optical attenuation (cm-1) with radiation dose in the range between 0 and 1000 cGy, and the local concentration of this complex can be probed using a green laser light (lambda = 543.5 nm). An optical computed tomography (CT) scanner was constructed analogous to a first-generation x-ray CT scanner, using a He-Ne laser, photodiodes, and rotation-translation stages controlled by a personal computer. The optical CT scanner itself can reconstruct attenuation coefficients to a baseline accuracy of < 2% while yielding dose images accurate to within 5% when other uncertainties are taken into account. Optical tomography is complicated by the reflection and refraction of light rays in the phantom materials, producing a blind spot in the transmission profiles which, results in a significant dose artifact in the reconstructed images. In this report we develop corrections used to reduce this artifact and yield accurate dosimetric maps. We also report the chemical reaction kinetics, the dose sensitivity and spatial resolution (< 1 mm3) obtained by optical absorption computed tomography. The article concludes with sample dose distributions produced by "cross-field" 6 MV x-ray beams, including a radiosurgery example.


Asunto(s)
Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiometría/instrumentación , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Ácido Benzoico , Fenómenos Biofísicos , Biofisica , Compuestos Ferrosos , Geles , Humanos , Óptica y Fotónica/instrumentación , Fantasmas de Imagen , Planificación de la Radioterapia Asistida por Computador/estadística & datos numéricos , Tecnología Radiológica , Xilenos
9.
J Chromatogr A ; 850(1-2): 381-9, 1999 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-10457501

RESUMEN

The environment-assisted cracking (EAC) susceptibility of some aluminum alloys used for airplane structural components currently limits their use in the peak strength condition. Understanding the mechanism of EAC will facilitate the development of crack-resistant alloys with optimum mechanical properties. One component towards understanding the fundamental processes responsible for EAC is a comprehensive knowledge of the chemical conditions within cracks. The present work uses capillary electrophoresis (CE) to quantify the crack chemistry in order to provide insight into the nature of the mechanism controlling cracking. The highly restricted geometry of cracks in metals means that a crack typically contains less than 10 microliters of solution. The high mass sensitivity combined with the inherently robust nature of CE makes it an ideal analytical technique for this application. Complicating factors in the accurate determination of the crack environment include high levels of sodium present from the test solution. Low sample volume and analyte matrix complexity necessitated the development of specific sampling, extraction and analysis methods. Analysis of the crack solutions in EAC-susceptible material revealed high levels of Al3+, Mg2+, Zn2+, and Cl- near the crack tip. Cations arise from the anodic dissolution of the alloy, whereas chloride ingress from the external environment occurs to maintain solution electroneutrality within the crack. In contrast, EAC-resistant material exhibited significantly lower concentrations of dissolution products.


Asunto(s)
Aleaciones/química , Aluminio/química , Electroforesis Capilar/métodos , Aleaciones/análisis , Aluminio/análisis , Aniones/análisis , Cationes/análisis , Corrosión , Oxidación-Reducción
10.
J Chromatogr A ; 850(1-2): 375-80, 1999 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-10457500

RESUMEN

Corrosion of aluminum alloy structures costs the US Air Force in the order of US$1 x 10(9) annually. Corrosion develops in areas of overlap such as aircraft lap-splice joints and under protective organic coatings. Capillary electrophoresis (CE) has been used to determine the local chemistries at these corrosion sites of solutions that were extracted using a microsampling system. Analysis of the local solution within lap-splice joints from aircraft has been performed in two ways: rehydration of corrosion products and direct microsampling. The solutions collected were analyzed with CE to quantitatively determine the species present during corrosion. The most common ions detected were Cl-, NO2-, NO3-, HCO3-, K+, Al3+, Ca2+, Na+ and Mg2+. Studies of the solution chemistry under local coating defects are required to understand coating failure and develop more durable coatings. A microsampling system and micro pH sensor were developed to extract solution from and measure pH in defects with diameters as small as 170 microns. Actively corroding defects contained high concentrations of Cl-, Al3+, Mg2+, Mn2+ and Cu2+ whereas only trace levels of Mg2+ were found in repassivated defects. The effects of these species on initiation and propagation of corrosion are discussed.


Asunto(s)
Aluminio/química , Electroforesis Capilar/métodos , Aeronaves , Aleaciones/química , Aluminio/análisis , Aniones/análisis , Cationes/análisis , Corrosión , Oxidación-Reducción
11.
J Pharm Sci ; 68(2): 216-9, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-423094

RESUMEN

A GLC analysis is presented for loxapine, amoxapine, and their major metabolites in serum and urine. Electron-capture detection is employed for serum analysis, and flame ionization is used for urine analysis. The procedure includes trifluoroacetylation of secondary amine functions, followed by trimethylsilylation of phenolic groups after ethyl acetate extraction of the sample. Urine requires prior enzymatic hydrolysis of conjugates. Data indicating the utility of the procedure in hospitalized patients and normal volunteers are presented.


Asunto(s)
Amoxapina/sangre , Amoxapina/orina , Dibenzoxazepinas/sangre , Dibenzoxazepinas/orina , Loxapina/sangre , Loxapina/orina , Cromatografía de Gases , Humanos , Hidroxilación , Métodos
12.
Farmaco ; 47(9): 1215-23, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1300127

RESUMEN

A chromatographic method for quantifying the potential memory-enhancing agent CL 275,838 (I) in human plasma with a limit of detection of 1.25 ng/ml is described. The procedure relies on isolation of the compounds from plasma constituents using the Sep-pack C18 cartridge, resolution by reverse-phase high pressure liquid chromatography (HPLC) and post-column oxidation of the eluate peak to from a derivative which can be measured by fluorescence detection. Peak height and compound I concentration were linearly related from 1.25 to 25 ng/ml. Intra- and inter-day validation studies indicated an acceptable precision and reproducibility of the method within the concentration range investigated, the overall coefficient of variation being less than 15%.


Asunto(s)
Memoria/efectos de los fármacos , Piperazinas/sangre , Pirazoles/sangre , Pirimidinas/sangre , Cromatografía Líquida de Alta Presión , Humanos , Masculino , Oxidación-Reducción , Piperazinas/química , Piperazinas/farmacología , Pirazoles/química , Pirazoles/farmacología , Pirimidinas/química , Pirimidinas/farmacología , Control de Calidad , Solventes , Espectrometría de Fluorescencia
17.
Cell Mol Life Sci ; 64(6): 643-5, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17380305

RESUMEN

Advances in our understanding of cardiac development have fuelled research into cellular approaches to myocardial repair of the damaged heart. In this collection of reviews we present recent advances into the basic mechanisms of heart development and the resident and non-resident progenitor cell populations that are currently being investigated as potential mediators of cardiac repair. Together these reviews illustrate that despite our current knowledge about how the heart is constructed, caution and much more research in this exciting field is essential. The current momentum to evaluate the potential for cardiac repair will in turn accelerate research into fundamental aspects of myocardial biology.


Asunto(s)
Biología Evolutiva , Corazón/embriología , Corazón/fisiología , Cicatrización de Heridas , Animales , Humanos , Células Madre/citología , Factores de Transcripción/metabolismo
18.
Genomics ; 24(3): 509-15, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7713502

RESUMEN

Tandem arrays of simple sequence repeat units are among the most unstable regions of mammalian genomes. Mutational instability at such loci depends on both repeat unit sequence and DNA sequences external to the tandem array, which have been recently implicated in polarized variability at human minisatellites. The characteristics of DNA sequences flanking the mouse minisatellite Ms6-hm have been investigated. This locus has a high mutation rate both in the germline and during early somatic development and is composed of a hypervariable tandem array of 500-2000 pentanucleotide repeat units flanked by a transposon-like long terminal repeat sequence of the mouse transcript (MT) family. A subpopulation of MT elements in the mouse genome are shown to flank a 1.1-kb internal sequence, consistent with their classification within a newly defined mammalian retrotransposon-like superfamily (MaLR). A second mouse minisatellite, Hm-2, also originates from within a MaLR LTR. Hm-2 is related to Ms6-hm in repeat unit sequence and profiles of germline and somatic instability; at both loci the tandem array has amplified from precisely the same point within the LTR. The similar origins of Ms6-hm and Hm-2 suggest that flanking MaLR sequences may be involved in mutational processes at these loci.


Asunto(s)
ADN Satélite/genética , Secuencias Repetitivas de Ácidos Nucleicos , Retroelementos , Animales , Secuencia de Bases , Secuencia de Consenso , Cartilla de ADN/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos , Datos de Secuencia Molecular , Mutación , Recombinación Genética , Homología de Secuencia de Ácido Nucleico
19.
Am Rev Respir Dis ; 123(6): 689-90, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7271070

RESUMEN

Fifteen male mice were given oral doses of 32 mg [14C]ethambutol/kg in a study of the tissue distribution of the drug. Animals were killed 1, 2, 4, 7, and 24 h after dosage and radioactivity in various tissues was measured. Peak concentrations were seen at 2 h after dosage. With the exception of brain, all tissues examined (liver, kidney, heart, spleen, lung, and muscle) developed tissue-to-plasma concentration ratios greater than 2. Highest values were seen in liver, kidney, and lung. High lung values were viewed as a favorable attribute for a drug used in the treatment of tuberculosis.


Asunto(s)
Radioisótopos de Carbono/metabolismo , Etambutol/metabolismo , Administración Oral , Animales , Riñón/metabolismo , Hígado/metabolismo , Pulmón/metabolismo , Masculino , Ratones , Factores de Tiempo , Distribución Tisular
20.
Virology ; 246(2): 317-28, 1998 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-9657950

RESUMEN

Although dengue (DEN) virus is the etiologic agent of dengue fever, the most prevalent vector-borne viral disease in the world, precise information on the antigenic structure of the dengue virion is limited. We have prepared a set of murine monoclonal antibodies (MAbs) specific for the envelope (E) glycoprotein of DEN 2 virus and used these antibodies in a comprehensive biological and biochemical analysis to identify 16 epitopes. Following domain nomenclature developed for the related flavivirus, tick-borne encephalitis, three functional domains were identified. Five epitopes associated with domain A were arranged in three spatially independent regions. These A-domain epitopes were destroyed by reduction, and antibodies reactive with these epitopes were able to block virus hemagglutination, neutralize virus infectivity, and block virus-mediated cell membrane fusion. Domain-A epitopes were present on the full-length E glycoprotein, a 45-kDa tryptic peptide representing its first 400 amino acids (aa) and a 22-kDa tryptic peptide representing at least aa 1-120. Four epitopes mapped into domain B, as determined by their partial resistance to reduction and the localization of these epitopes on a 9-kDa tryptic or chymotryptic peptide fragment (aa 300-400). One domain-B-reactive MAb was also capable of binding to a DEN 2 synthetic peptide corresponding to aa 333-351 of the E glycoprotein, confirming the location of this domain. Domain-B epitopes elicited MAbs that were potent neutralizers of virus infectivity and blocked hemagglutination, but they did not block virus-mediated cell-membrane fusion. Domains A and B were spatially associated. As with tick-borne encephalitis virus, determination of domain C was more problematic; however, at least four epitopes had biochemical characteristics consistent with C-domain epitopes.


Asunto(s)
Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Virus del Dengue/inmunología , Mapeo Epitopo , Epítopos de Linfocito B/inmunología , Proteínas del Envoltorio Viral/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Antígenos Virales/química , Sitios de Unión , Unión Competitiva , Línea Celular , Epítopos de Linfocito B/química , Pruebas de Inhibición de Hemaglutinación , Humanos , Jamaica , Masculino , Fusión de Membrana , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Pruebas de Neutralización , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/inmunología , Mapeo Peptídico , Conformación Proteica , Relación Estructura-Actividad , Proteínas del Envoltorio Viral/química
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