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1.
Med Teach ; 28(5): 443-6, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16973458

RESUMEN

If it is accepted that new doctors must be 'Fit to Practice' in a standard clinical house job, they should be competent in basic communication skills. Although these skills may be assessed as part of a routine OSCE-style exam in the course of the curriculum, the question is raised whether students who fail to demonstrate a minimal level of competence in this area should to be allowed to progress to the next stage of the course and eventually graduate. This paper describes our experiences with introducing 'barrier' stations in communication skills into the OSCE. Students who failed these stations, irrespective of their overall exam performance, undertook remedial studies in a compulsory two-week directed study module followed by a four-station OSCE.


Asunto(s)
Competencia Clínica , Comunicación , Educación de Pregrado en Medicina , Reentrenamiento en Educación Profesional , Evaluación Educacional , Derivación y Consulta , Estudiantes de Medicina , Humanos
2.
J Thromb Haemost ; 4(6): 1388-95, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16706986

RESUMEN

BACKGROUND: Septins are important effectors in molecular mechanisms involving membrane partitioning. To date, a growing repertoire of septins in mammals includes 13 different proteins (SEPT1 to SEPT13) that can be classified into four distinct categories based on sequence similarity. AIM: In this study, we document the human platelet septin, SEPT5, as part of a complex composed of multiple septin proteins. RESULTS: Biochemical and immunofluorescent data place the majority of these complexes in the platelet periphery as part of the platelet circumferential band copurifying with the platelet microtubule coil and tubulin. The presence of a prominent platelet septin ring in resting platelets appears to be left intact in the activated platelet, as a similar ring structure is observed following platelet spreading on fibrinogen. The ablation of SEPT5 in the knock-out mouse model had previously been reported to result in a platelet phenotype with aggregation using subthreshold levels of agonist. Speculation on the role of SEPT5 in the platelet-release reaction suggested that SEPT5 regulates platelet function by association with platelet storage granules. We now report that the absence of SEPT5 results in increased ATP release from stimulated platelets. CONCLUSION: These studies document the presence of platelet septin complexes and validate the importance of septins for platelet physiology.


Asunto(s)
Plaquetas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Unión al GTP/metabolismo , Microtúbulos/metabolismo , Tubulina (Proteína)/metabolismo , Adenosina Trifosfato/biosíntesis , Animales , Plaquetas/efectos de los fármacos , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Colágeno Tipo I/farmacología , Proteínas del Citoesqueleto , Proteínas de Unión al GTP/química , Humanos , Ratones , Ratones Noqueados , Microtúbulos/química , Nocodazol/farmacología , Unión Proteica , Septinas , Tubulina (Proteína)/química , Moduladores de Tubulina/farmacología
3.
J Hand Surg Br ; 31(3): 311-6, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16476513

RESUMEN

Twenty cases of scapho-lunate instability have been reviewed, to determine the effect of dorsal capsulodesis on disability and wrist pain. The average follow-up was 41 (range 13-63) months. There was a significant improvement in the pre-operative Patient Rated Wrist Evaluation score from 108 (range 18-150) to a postoperative score of 60 (range 0-132). All wrist movements and grip strength were reduced postoperatively but only the reductions in flexion and radial deviation were statistically significant. Seventeen (85%) patients were satisfied with the operation. One patient remained unemployed after surgery. Five patients returned to their normal jobs. This study shows that dorsal capsulodesis should remain an important option in the treatment of scapholunate instability.


Asunto(s)
Articulaciones del Carpo/cirugía , Cápsula Articular/cirugía , Inestabilidad de la Articulación/cirugía , Hueso Semilunar/cirugía , Hueso Escafoides/cirugía , Adolescente , Adulto , Articulaciones del Carpo/fisiopatología , Evaluación de la Discapacidad , Empleo , Femenino , Estudios de Seguimiento , Fuerza de la Mano/fisiología , Humanos , Cápsula Articular/fisiopatología , Inestabilidad de la Articulación/fisiopatología , Ligamentos Articulares/lesiones , Ligamentos Articulares/cirugía , Hueso Semilunar/fisiopatología , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Satisfacción del Paciente , Rango del Movimiento Articular/fisiología , Hueso Escafoides/fisiopatología , Fibrocartílago Triangular/lesiones , Fibrocartílago Triangular/cirugía
6.
Med Teach ; 23(2): 171-175, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11371294

RESUMEN

An Ambulatory Care Teaching Centre (ACTC) has provided an opportunity to develop an integrated teaching programme in a supervised environment which links students' initial clinical experiences in the skills centre with patient-contact in other teaching settings. Second-year students attended 2-h sessions in the ACTC during each block of a systems-based course. Two 'system-sensitive' patients invited from a patient bank enabled students to develop clinical skills previously practised on mannequins and simulated patients and to integrate theoretical material with clinical practice. A programme co-ordinator timetabled student, patient and tutor attendances. Students particularly appreciated the protected environment where they could practice clinical skills under supervision before interviewing other patients in patient-centred clinical settings. Tutors appreciated an environment which eliminated tensions often present between teaching and service delivery. They enjoyed focussed teaching sessions especially if details of invited patients were known in advance and 'backup' resources were available. Patients enjoyed opportunities to contribute to clinical teaching.

7.
Med Teach ; 23(4): 345-350, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12098380

RESUMEN

The ambulatory care setting is becoming an increasingly important environment for clinical teaching. This reflects the changing focus of healthcare delivery with more procedures and patient treatment being delivered in this setting. Maximizing learning opportunities for students without compromising patient care has never provided a greater challenge. This paper shares 12 educational tips for developing an ambulatory care teaching centre where both students and patients benefit from a protected yet realistic clinical setting.

8.
J Biol Chem ; 275(17): 12763-8, 2000 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-10777573

RESUMEN

Binding of the von Willebrand factor (vWF) A1 domain to the glycoprotein (GP) Ib-IX-V complex mediates platelet adhesion to reactive substrates under high shear stress conditions, a key event in hemostasis and thrombosis. We have now used the known three-dimensional structure of the A1 domain to model the interaction with the GP Ibalpha sequence 271-279, which has previously been implicated in ligand binding. Docking procedures suggested that A1 domain residues in strand beta3 and preceding loop (residues 559-566) as well as in helix alpha3 (residues 594-603) interact with Asp residues 272, 274, 277 and sulfated Tyr residues 278 and 279 in GP Ibalpha. To verify this model, 14 mutant A1 domain fragments containing single or multiple side chain substitutions were tested for their ability to mediate platelet adhesion under flow. Each of the vWF residues Tyr(565), Glu(596), and Lys(599) proved to be strictly required for A1 domain function, which, in agreement with previous findings, was also dependent on Gly(561). Moreover, an accessory functional role was apparent for a group of positively charged residues, including Arg at positions 629, 632, 636 and Lys at positions 643 and 645, possibly acting in concert. There was, however, no evidence from the model that these residues directly participate in forming the complex with GP Ibalpha. These results provide a partial model of the vWF-GP Ibalpha interaction linked to the manifestation of functional activity in platelet adhesion.


Asunto(s)
Complejo GPIb-IX de Glicoproteína Plaquetaria/metabolismo , Factor de von Willebrand/química , Aminoácidos/química , Plaquetas/química , Plaquetas/metabolismo , Adhesión Celular , Simulación por Computador , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Mutagénesis , Complejo GPIb-IX de Glicoproteína Plaquetaria/química , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Recombinantes/metabolismo , Factor de von Willebrand/metabolismo
9.
Proc Natl Acad Sci U S A ; 97(6): 2674-9, 2000 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-10716995

RESUMEN

The ability of organisms to evolve resistance threatens the effectiveness of every antibiotic drug. We show that in the nematode Caenorhabditis elegans, simultaneous mutation of three genes, avr-14, avr-15, and glc-1, encoding glutamate-gated chloride channel (GluCl) alpha-type subunits confers high-level resistance to the antiparasitic drug ivermectin. In contrast, mutating any two channel genes confers modest or no resistance. We propose a model in which ivermectin sensitivity in C. elegans is mediated by genes affecting parallel genetic pathways defined by the family of GluCl genes. The sensitivity of these pathways is further modulated by unc-7, unc-9, and the Dyf (dye filling defective) genes, which alter the structure of the nervous system. Our results suggest that the evolution of drug resistance can be slowed by targeting antibiotic drugs to several members of a multigene family.


Asunto(s)
Antinematodos/farmacología , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/genética , Resistencia a Medicamentos/genética , Ivermectina/farmacología , Animales , Caenorhabditis elegans/efectos de los fármacos , Canales de Cloruro/genética , Clonación Molecular , Electrofisiología , Ácido Glutámico/farmacología , Proteínas del Helminto/genética , Modelos Biológicos , Modelos Genéticos , Mutación , Faringe/efectos de los fármacos , Unión Proteica
10.
Genetics ; 154(2): 635-46, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10655217

RESUMEN

The pharynx of Caenorhabditis elegans is a neuromuscular organ responsible for feeding, concentrating food by its pumping movement. A class of mutants, the eat mutants, are defective in this behavior. We have identified a novel eat gene, eat-20, encoding a unique transmembrane protein with three EGF motifs. Staining with a specific polyclonal antibody reveals that EAT-20 is expressed predominantly in the pharyngeal muscles and a subset of neurons. Some hypodermal cells also express EAT-20. eat-20 mutant animals are starved, have smaller brood sizes, and have prolonged egg-laying periods. The starvation apparently results from pharyngeal pumping defects, including a reduced pumping rate and "slippery pumping," in which the contents of the pharynx sometimes move rostrally. However, electrical activity of eat-20 mutants appears normal by electropharyngeogram.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/fisiología , Factor de Crecimiento Epidérmico/genética , Conducta Alimentaria , Proteínas de la Membrana/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Caenorhabditis elegans/genética , Clonación Molecular , ADN Complementario , Prueba de Complementación Genética , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Mutación
11.
Blood ; 94(1): 172-8, 1999 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10381510

RESUMEN

Aggregation of blood platelets contributes to the arrest of bleeding at sites of vascular injury, but it can occlude atherosclerotic arteries and precipitate diseases such as myocardial infarction. The bonds that link platelets under flow conditions were identified using confocal videomicroscopy in real time. Glycoprotein (GP) Ibalpha and von Willebrand factor (vWF) acted in synergy with alphaIIbbeta3 and fibrinogen to sustain platelet accrual at the apex of thrombi where three-dimensional growth resulted in increasing shear rates. The specific function of distinct adhesion pathways in response to changing hemodynamic conditions helps to explain hemostatic and thrombotic processes.


Asunto(s)
Plaquetas/citología , Plaquetas/fisiología , Adhesividad Plaquetaria/fisiología , Fibrinógeno/fisiología , Fibrinógeno/ultraestructura , Humanos , Microscopía Confocal , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/fisiología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/ultraestructura , Complejo GPIb-IX de Glicoproteína Plaquetaria/fisiología , Complejo GPIb-IX de Glicoproteína Plaquetaria/ultraestructura , Factor de von Willebrand/fisiología , Factor de von Willebrand/ultraestructura
12.
Science ; 286(5449): 2501-4, 1999 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-10617464

RESUMEN

The nematode pharynx has a potassium channel with unusual properties, which allows the muscles to repolarize quickly and with the proper delay. Here, the Caenorhabditis elegans exp-2 gene is shown to encode this channel. EXP-2 is a Kv-type (voltage-activated) potassium channel that has inward-rectifying properties resembling those of the structurally dissimilar human ether-à-go-go-related gene (HERG) channel. Null and gain-of-function mutations affect pharyngeal muscle excitability in ways that are consistent with the electrophysiological behavior of the channel, and thereby demonstrate a direct link between the kinetics of this unusual channel and behavior.


Asunto(s)
Caenorhabditis elegans/fisiología , Canales de Potasio/fisiología , Potenciales de Acción , Animales , Caenorhabditis elegans/genética , Conducta Alimentaria , Genes de Helminto , Genes Reporteros , Activación del Canal Iónico , Cinética , Potenciales de la Membrana , Modelos Moleculares , Músculos/metabolismo , Mutación , Neuronas/metabolismo , Oocitos/metabolismo , Músculos Faríngeos/fisiología , Canales de Potasio/química , Canales de Potasio/genética , Conformación Proteica , ARN Complementario/genética , Proteínas Recombinantes de Fusión/biosíntesis , Xenopus laevis
13.
Mech Dev ; 72(1-2): 179-82, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9533963

RESUMEN

let-60 ras plays roles in the differentiation of several C. elegans tissues (Yochem, J., Sundaram, M., Han, M., 1997. Ras is required for a limited number of cell fates and not for general proliferation in Caenorhabditis elegans. Mol. Cell. Biol. 17, 2716-2722). To understand the transcriptional regulation of ras and to identify new functions for ras in development, we examined expression patterns of let-60::lacZ and let-60::GFP reporter constructs in C. elegans hermaphrodites. Fusion constructs were expressed in vulval precursor cells, sex myoblasts and in cell lineages of the somatic gonad, germline cells (GFP construct only), hypodermis, muscle and nervous system.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/genética , Expresión Génica , Genes Reporteros , Proteínas del Helminto/genética , Proteínas ras/genética , Animales , Caenorhabditis elegans/embriología , Diferenciación Celular/genética
14.
EMBO J ; 16(19): 5867-79, 1997 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-9312045

RESUMEN

Ivermectin is a widely used anthelmintic drug whose nematocidal mechanism is incompletely understood. We have used Caenorhabditis elegans as a model system to understand ivermectin's effects. We found that the M3 neurons of the C.elegans pharynx form fast inhibitory glutamatergic neuromuscular synapses. avr-15, a gene that confers ivermectin sensitivity on worms, is necessary postsynaptically for a functional M3 synapse and for the hyperpolarizing effect of glutamate on pharyngeal muscle. avr-15 encodes two alternatively spliced channel subunits that share ligand binding and transmembrane domains and are members of the family of glutamate-gated chloride channel subunits. An avr-15-encoded subunit forms a homomeric channel that is ivermectin-sensitive and glutamate-gated. These results indicate that: (i) an ivermectin-sensitive chloride channel mediates fast inhibitory glutamatergic neuromuscular transmission; and (ii) a nematocidal property of ivermectin derives from its activity as an agonist of glutamate-gated chloride channels in essential excitable cells such as those of the pharynx.


Asunto(s)
Antinematodos/farmacología , Caenorhabditis elegans/efectos de los fármacos , Canales de Cloruro/metabolismo , Ácido Glutámico/metabolismo , Ivermectina/farmacología , Transmisión Sináptica/efectos de los fármacos , Empalme Alternativo , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Canales de Cloruro/efectos de los fármacos , Canales de Cloruro/genética , Iontoforesis , Datos de Secuencia Molecular , Relajación Muscular/efectos de los fármacos , Faringe/metabolismo
15.
Med Educ ; 29(1): 58-60, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7623688

RESUMEN

In undergraduate medical education, a shift away from in-patient teaching towards greater use of the ambulatory care setting is occurring. This paper looks at what effect this change in emphasis might have on students' clinical competence. A log-book approach was used to study final-year orthopaedic students' opportunities to interact with patients in the wards and out-patient clinics at the University of Dundee Medical School. Students perceived that similar opportunities to interact with patients to develop and improve their clinical skills were provided by both settings. The study showed that much greater use could be made of both settings for clinical skills teaching. While students were not enthusiastic about the log-book approach, it stimulated their thinking. It is concluded that student opportunities to develop clinical skills will not be adversely affected by the trend towards ambulatory care teaching. There should be more clinical teaching in the out-patient setting.


Asunto(s)
Atención Ambulatoria , Educación de Pregrado en Medicina , Relaciones Profesional-Paciente , Enseñanza/métodos , Competencia Clínica , Inglaterra , Humanos
16.
J Cell Sci ; 107 ( Pt 6): 1609-22, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7962201

RESUMEN

The tail domain of the intermediate filament (IF) protein vimentin is unnecessary for IF assembly in vitro. To study the role of vimentin's tail in vivo, we constructed a plasmid that directs the synthesis of a 'myc-tagged' version of the Xenopus vimentin-1 tail domain in bacteria. This polypeptide, mycVimTail, was purified to near homogeneity and injected into cultured Xenopus A6 cells. In these cells the tail polypeptide co-localized with actin even in the presence of cytochalasin. Two myc-tagged control polypeptides argue for the specificity of this interaction. First, a similarly myc-tagged lamin tail domain localizes to the nucleus, indicating that the presence of the myc tag did not itself confer the ability to co-localize with actin (Hennekes and Nigg (1994) J. Cell Sci. 107, 1019-1029). Second, a myc-tagged polypeptide with a molecular mass and net charge at physiological pH (i.e. -4) similar to that of the mycVimTail polypeptide, failed to show any tendency to associate with actin-containing structures, indicating that the interaction between mycVimTail and actin-containing structures was not due to a simple ionic association. Franke (1987; Cell Biol. Int. Rep. 11, 831) noted a similarity in the primary sequence between the tail of the type I keratin DG81A and vimentin. To test whether the DG81A tail interacted with actin-containing structures, we constructed and purified myc-tagged DG81A tail polypeptides. Unexpectedly, these keratin tail polypeptides were largely insoluble under physiological conditions and formed aggregates at the site of injection. While this insolubility made it difficult to determine if they associated with actin-containing structures, it does provide direct evidence that the tails of vimentin and DG81A differ dramatically in their physical properties. Our data suggest that vimentin's tail domain has a highly extended structure, binds to actin-containing structures and may mediate the interaction between vimentin filaments and microfilaments involved in the control of vimentin filament organization (Hollenbeck et al. (1989) J. Cell Sci. 92, 621; Tint et al. (1991) J. Cell Sci. 98, 375).


Asunto(s)
Actinas/metabolismo , Vimentina/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Células Cultivadas , Fenómenos Químicos , Química Física , Citocalasina B/farmacología , Genes myc , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Vimentina/química , Xenopus
17.
Med Educ ; 28(3): 208-12, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8035712

RESUMEN

In undergraduate medical education there is a trend away from ward-based teaching towards out-patient and community-based teaching. To study the potential effects of this altered emphasis on student learning, a pilot group of final-year medical students at the University of Dundee was asked to keep individual structured log-books. These contained details of patients seen during their 3-week orthopaedic attachment in both a ward and out-patient setting. A comparison of perceived learning in the two settings showed that students learned more from attending an out-patient clinic than a ward round, but did not make full use of the learning potential of either. The setting did not particularly influence the balance of learning as categorized here but only the ward round supplied experience of surgical complications. The amount of learning taking place in an out-patient clinic was influenced by student ability, measured by examination performance, but not by clinic work-load. The implications of increased use of out-patient clinics and the advantages and disadvantages of the approach employed are discussed. It is concluded that in the situation studied student learning in the outpatient setting is as good as or superior to the ward setting but should not totally replace it.


Asunto(s)
Aprendizaje , Atención Ambulatoria , Competencia Clínica , Medicina Clínica , Educación de Pregrado en Medicina , Humanos , Escocia
19.
J R Coll Surg Edinb ; 38(5): 315-9, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7506787

RESUMEN

In an attempt to simplify the choice of the many tests available for the assessment of hand function nine commonly used tests assessing different modalities of hand function have been evaluated on a small group of patients. The tests are judged by how well they fulfil the criteria of being simple and quick to use, easy to replicate, relevant to the needs of the patient, objective and inexpensive to acquire. The five tests which most fulfilled these criteria have been used to form a concise and practical hand assessment pro forma.


Asunto(s)
Mano/fisiología , Músculos/fisiología , Actividades Cotidianas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Destreza Motora , Contracción Muscular , Dimensión del Dolor , Rango del Movimiento Articular , Reproducibilidad de los Resultados
20.
Prosthet Orthot Int ; 17(2): 130-5, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8233770

RESUMEN

This paper reviews the literature comparing the results obtained in applying regimes involving motion with those involving rest following injury or surgery. The deleterious effects of immobilisation are compared to those obtained under conditions of passive motion and intermittent passive motion. It is concluded that continuous passive motion (CPM) represents an improvement on intermittent motion. Models of CPM machines are described and some results presented. It is proposed that "intelligent" CPM would represent a further improvement in technique and a prototype machine for this purpose and some preliminary results are described.


Asunto(s)
Mano/cirugía , Inmovilización/efectos adversos , Terapia Pasiva Continua de Movimiento/métodos , Descanso , Animales , Perros , Diseño de Equipo , Estudios de Evaluación como Asunto , Humanos , Terapia Pasiva Continua de Movimiento/instrumentación , Cuidados Posoperatorios , Conejos , Resultado del Tratamiento
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