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1.
Can Med Educ J ; 11(5): e92-e96, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33062098

RESUMEN

Competency-based medical education (CBME) curricula are becoming increasingly common in graduate medical education. Put simply, CBME is focused on educational outcomes, is independent of methods and time, and is composed of achievable competencies.1 In spite of widespread uptake, there remains much to learn about implementing CBME at the program level. Leveraging the collective experience of program leaders at Queen's University, where CBME simultaneously launched across 29 specialty programs in 2017, this paper leverages change management theory to provide a short summary of how program leaders can navigate the successful preparation, launch, and initial implementation of CBME within their residency programs.


Les programmes de formation médicale fondée sur les compétences (FMFC) sont de plus en plus répandus dans les études supérieures en médecine. En termes simples, la FMFC est centrée sur les résultats scolaires, elle est indépendante des méthodes et du temps, et est constituée de compétences réalisables.1 Malgré cette adoption généralisée, il reste encore beaucoup à apprendre sur la mise en œuvre de la FMFC au niveau des programmes. Tirant profit de l'expérience collective des responsables de programmes à l'Université Queen, où la FMFC a été lancée simultanément dans 29 programmes de spécialité en 2017,le présent article s'appuie sur la théorie de la gestion du changement pour produire un court résumé de la manière dont les responsables de programmes peuvent gérer avec succès la préparation, le lancement et la mise en œuvre initiale de la FMFC au sein de leurs programmes de résidence.

2.
Mol Genet Genomics ; 269(1): 137-49, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12715162

RESUMEN

The sex chromosome constitution of the silkworm, Bombyx mori, is ZW in the female and ZZ in the male. Very little molecular information is available about the Z chromosome in Lepidoptera, although the topic is interesting because of the absence of gene dosage compensation in this chromosome. We constructed a 320-kb BAC contig around the Bmkettin gene on the Z chromosome in Bombyx and determined its nucleotide sequence by the shotgun method. We found 13 novel protein-coding sequences in addition to Bmkettin. All the transposable elements detected in the region were truncated, and no LTR retrotransposons were found, in stark contrast to the situation on the W chromosome. In this 320-kb region, four genes for muscle proteins (Bmkettin, Bmtitin1, Bmtitin2, and Bmprojectin) are clustered, together with another gene (Bmmiple) on the Z chromosome in B. mori; their orthologs are also closely linked on chromosome 3 in Drosophila, suggesting a partial synteny. Real-time RT-PCR experiments demonstrated that transcripts of 13 genes of the 14 Z-linked genes found accumulated in larger amounts in males than in female moths, indicating the absence of gene dosage compensation. The implications of these findings for the evolution and function of the Z chromosome in Lepidoptera are discussed.


Asunto(s)
Bombyx/genética , Proteínas de Drosophila , Genes de Insecto , Proteínas de Insectos/genética , Proteínas Musculares/genética , Cromosomas Sexuales/genética , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Mapeo Cromosómico , Paseo de Cromosoma , Cromosomas Artificiales Bacterianos/genética , Conectina , Mapeo Contig , Etiquetas de Secuencia Expresada , Femenino , Biblioteca de Genes , Masculino , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Caracteres Sexuales
3.
Br J Ophthalmol ; 87(3): 307-11, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12598444

RESUMEN

AIM: To examine the relation between the type of choroidal neovascularisation (CNV) in the first eye and age related maculopathy (ARM) severity in the fellow eye. METHODS: Colour fundus photographs and fluorescein angiograms from 67 subjects with a clinical diagnosis of CNV in one eye were scrutinised. CNV was classified as wholly classic, predominantly classic, minimally classic, or occult based on the proportion of classic leakage within the lesion. ARM changes in the fellow eye were assigned a severity stage using the system described by the Rotterdam Eye Study. Logistic regression analysis was employed to examine the association between CNV subtype and ARM stage. RESULTS: Of subjects with classic or predominantly classic CNV in the first eye 78% exhibited least no or early ARM features in the fellow eye. By contrast, 85% of subjects with minimally classic or occult CNV in the first eye exhibited more advanced ARM features in the fellow eye. Kruskall-Wallis one way ANOVA by ranks showed that this was highly significant (p = 0.002). Logistic regression analysis showed that as the proportion of occult CNV increased in the first eye, fellow eyes of subjects in this category were more likely to have been assigned to a higher ARM stage (p = 0.019). The area occupied by the CNV in the first eye also influenced severity of ARM changes in the fellow eye. CONCLUSION: The type and extent of CNV in the first affected eye has a distinct relation to ARM severity in the fellow eye. Fellow eyes of subjects with minimally classic or occult CNV in the first affected eye show widespread ARM changes suggestive of retinal pigment epithelial dysfunction. These findings suggest that classic CNV may be focal disease while occult CNV is essentially a more widespread retinal pigment epithelial disorder.


Asunto(s)
Neovascularización Coroidal/complicaciones , Degeneración Macular/complicaciones , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Neovascularización Coroidal/clasificación , Femenino , Angiografía con Fluoresceína/métodos , Humanos , Modelos Logísticos , Mácula Lútea/irrigación sanguínea , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
4.
J Steroid Biochem Mol Biol ; 79(1-5): 41-7, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11850206

RESUMEN

We have investigated aromatase and the inducible cyclooxygenase COX-2 expression using immunocytochemistry in tumors of a series of patients with advanced breast cancer treated with aromatase inhibitors. Aromatase was expressed in 58/102 breast cancers. This is similar to the percentage previously reported for aromatase activity. Interestingly, aromatase was expressed in a variety of cell types, including tumor, stromal, adipose, and endothelial cells. Since prostaglandin E2 is known to regulate aromatase gene expression and is the product of COX-2, an enzyme frequently overexpressed in tumors, immunocytochemistry was performed on the tissue sections using a polyclonal antibody to COX-2. Aromatase was strongly correlated (P<0.001) with COX-2 expression. These results suggest that PGE2 produced by COX-2 in the tumor may be important in stimulating estrogen synthesis in the tumor and surrounding tissue. No correlation was observed between aromatase or COX-2 expression and the response of the patients to aromatase inhibitor treatment. However, only 13 patients responded. Nine of these patients were aromatase positive. Although similar to responses in other studies, this low response rate to second line treatment suggests that tumors of most patients were no longer sensitive to the effects of estrogen. Recent clinical studies suggest that greater responses occur when aromatase inhibitors are used as first line treatment. In the intratumoral aromatase mouse model, expression of aromatase in tumors is highly correlated with increased tumor growth. First line treatment with letrozole was effective in all animals treated and was more effective than tamoxifen in suppressing tumor growth. Letrozole was also effective in tumors failing to respond to tamoxifen, consistent with clinical findings. In addition, the duration of response was significantly longer with the aromatase inhibitor than with tamoxifen, suggesting that aromatase inhibitors may offer better control of tumor growth than this antiestrogen.


Asunto(s)
Aromatasa/metabolismo , Neoplasias de la Mama/enzimología , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Adipocitos/enzimología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Inhibidores de la Aromatasa , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Ciclooxigenasa 2 , Dinoprostona/metabolismo , Endotelio/enzimología , Inhibidores Enzimáticos/uso terapéutico , Células Epiteliales/enzimología , Moduladores de los Receptores de Estrógeno/uso terapéutico , Estrógenos/biosíntesis , Femenino , Humanos , Inmunohistoquímica , Letrozol , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Mamarias Experimentales/patología , Proteínas de la Membrana , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Neoplasias Hormono-Dependientes/enzimología , Nitrilos/uso terapéutico , Células del Estroma/enzimología , Tamoxifeno/uso terapéutico , Triazoles/uso terapéutico
6.
Genomics ; 43(3): 366-75, 1997 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-9268640

RESUMEN

We have constructed a 1-Mb contig in human chromosomal band 11p15.5, a region implicated in the etiology of several embryonal tumors, including Wilms tumor, and in Beckwith-Wiedemann syndrome. Cosmid, P1, PAC, and BAC clones were characterized by NotI/SalI digestion and hybridized to a variety of probes to generate a detailed physical map that extends from D11S517 to L23MRP. Included in the map are the CARS, NAP2, p57/KIP2, KVLQT1, ASCL2, TH, INS, IGF2, H19, and L23MRP genes as well as end probes isolated from PACs. The TAPA1 gene, whose protein product can transmit an antiproliferative signal, was also localized in the contig. However, Northern blot analysis demonstrated that its expression did not correlate with tumorigenicity in G401 Wilms tumor hybrids, suggesting that TAPA1 is not responsible for the tumor suppression associated with 11p15.5. Genomic clones were used as probes in FISH analysis to map the breakpoints from three Beckwith-Wiedemann syndrome patients and a rhabdoid tumor. Interestingly, each of the breakpoints disrupts the KVLQT1 gene, which is spread over a 400-kb region of the contig. Since 11p15.5 contains several genes with imprinted expression and one or more tumor suppressor genes, our contig and map provide a framework for characterizing this intriguing genetic environment.


Asunto(s)
Antígenos CD/genética , Cromosomas Humanos Par 11/genética , ADN Recombinante , Genes Relacionados con las Neoplasias/genética , Genes Supresores/genética , Genes del Tumor de Wilms/genética , Impresión Genómica/genética , Mapeo Restrictivo , Antígenos CD/biosíntesis , Bacteriófago P1/genética , Síndrome de Beckwith-Wiedemann/genética , Fragilidad Cromosómica , Mapeo Cromosómico , ADN/análisis , ADN/aislamiento & purificación , Expresión Génica/genética , Expresión Génica/fisiología , Vectores Genéticos/genética , Humanos , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/genética , Tetraspanina 28
8.
Nat Genet ; 14(3): 269-76, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8896555

RESUMEN

The gene for spinocerebellar ataxia type 2 (SCA2) has been mapped to 12q24.1. A 1.1-megabase contig in the candidate region was assembled in P1 artificial chromosome and bacterial artificial chromosome clones. Using this contig, we identified a CAG trinucleotide repeat with CAA interruptions that was expanded in patients with SCA2. In contrast to other unstable trinucleotide repeats, this CAG repeat was not highly polymorphic in normal individuals. In SCA2 patients, the repeat was perfect and expanded to 36-52 repeats. The most common disease allele contained (CAG)37, one of the shortest expansions seen in a CAG expansion syndrome. The repeat occurs in the 5'-coding region of SCA2 which is a member of a novel gene family.


Asunto(s)
Cromosomas Humanos Par 12 , Proteínas/genética , Degeneraciones Espinocerebelosas/genética , Repeticiones de Trinucleótidos , Secuencia de Aminoácidos , Ataxinas , Secuencia de Bases , Mapeo Cromosómico , ADN Complementario/aislamiento & purificación , Regulación de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
9.
Biochem Biophys Res Commun ; 222(1): 171-7, 1996 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-8630064

RESUMEN

The mouse gene U2 auxiliary factor binding protein related sequence (U2afbp-rs) has previously been shown to be genomically imprinted with monoallelic expression from the paternal allele. To determine if the human homologue is imprinted and contains conserved structural features which regulate imprinting, we isolated genomic clones from a human P1-derived artificial chromosome (PAC) library that map to human chromosome 5q22-31, a region syntenic to the proximal portion of mouse chromosome 11 where U2afbp-rs resides. A genomic subclone was isolated which contained an open reading frame with high homology to the mouse gene. This subclone also maintained the intronless character of the mouse gene. A KpnI polymorphism within the open reading frame of the gene was found to occur in 21% (8/38) of the alleles tested from human placental tissue samples. RT-PCR analysis of human placentas using the KpnI polymorphism to determine the parental origin of the alleles indicates biallelic expression of the human chromosome 5 U2AFBPL gene.


Asunto(s)
Impresión Genómica , Proteínas del Tejido Nervioso , Proteínas Nucleares , Ribonucleoproteínas/genética , Alelos , Animales , Cromosomas Humanos Par 5 , Cartilla de ADN/química , Genes , Humanos , Ratones , Placenta/fisiología , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo Restrictivo , Ribonucleoproteínas Nucleares Pequeñas , Factor de Empalme U2AF
11.
Genomics ; 17(3): 776-9, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8244398

RESUMEN

Fifty-nine NotI linking clones have been isolated from a flow-sorted chromosome 22 cosmid library and mapped using fluorescence in situ hybridization and/or a panel of somatic cell hybrids. Fourteen clones map to the short arm of chromosome 22, 31 to the long arm, and 9 to other chromosomes; 5 clones could not be unambiguously mapped. To identify potentially informative genetic markers, the chromosome 22 clones were screened for poly(CA) sequences; 24 positively hybridizing clones, 10 on the long arm and 14 on the short arm, were identified. These clones will be useful for constructing a long-range restriction map of chromosome 22 and may facilitate the cloning of chromosome 22 genes.


Asunto(s)
Cromosomas Humanos Par 22 , Desoxirribonucleasas de Localización Especificada Tipo II , Secuencia de Bases , Mapeo Cromosómico , Clonación Molecular , Cósmidos , ADN/genética , Biblioteca de Genes , Humanos , Células Híbridas , Oligodesoxirribonucleótidos/genética , Secuencias Repetitivas de Ácidos Nucleicos
12.
Hum Mol Genet ; 2(9): 1361-8, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8242058

RESUMEN

In order to permit detailed characterization of meningioma cases showing deletions within chromosomal band 22q12 and further systematically clone genes located within this region, we established a genomic YAC and cosmid contig which encompasses a region in excess of 1000 kb of 22q12. The YAC contig consists of 6 YAC clones arranged into 5 overlapping steps covering more than 1100 kb. Two corresponding cosmid contigs consisting of 40 steps of overlapping groups of cosmids encompasses 900-1000 kb. This set of genomic clones provides a detailed physical map of this part of chromosome 22 and constitutes a basis for the isolation and characterization of genes that may be located within this chromosomal region. Employing the exon-amplification method on two cosmids from the contig, we cloned a novel, anonymous gene, pK1.3, which potentially encodes a protein of 683 amino acids with a predicted molecular weight of of 78.5 kD. Its 2.7 kb mRNA is expressed ubiquitously. We estimated the genomic size of this gene to 100-150 kb, and it is located in the immediate centromeric vicinity of the neurofibromatosis 2 (NF2) tumor suppressor gene.


Asunto(s)
Cromosomas Humanos Par 22 , Genes de la Neurofibromatosis 2 , Neoplasias Meníngeas/genética , Meningioma/genética , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Cromosomas Artificiales de Levadura , Clonación Molecular , Cósmidos , ADN Complementario/genética , ADN de Neoplasias/genética , Exones , Eliminación de Gen , Genes Supresores de Tumor , Humanos , Datos de Secuencia Molecular , Sarcoma de Ewing/genética
13.
Genetics ; 113(2): 405-15, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3013724

RESUMEN

The role of genomic alterations in mutagenesis induced by ionizing radiation has been the subject of considerable speculation. By Southern blotting analysis we show here that 9 of 55 (approximately 1/6) gamma-ray-induced mutants at the adenine phosphoribosyl transferase (aprt) locus of Chinese hamster ovary (CHO) cells have a detectable genomic rearrangement. These fall into two classes: intragenic deletions and chromosomal rearrangements. In contrast, no major genomic alterations were detected among 67 spontaneous mutants, although two restriction site loss events were observed. Three gamma-ray-induced mutants were found to be intragenic deletions; all may have identical break-points. The remaining six gamma-ray-induced mutants demonstrating a genomic alteration appear to be the result of chromosomal rearrangements, possibly translocation or inversion events. None of the remaining gamma-ray-induced mutants showed any observable alteration in blotting pattern indicating a substantial role for point mutation in gamma-ray-induced mutagenesis at the aprt locus.


Asunto(s)
Adenina Fosforribosiltransferasa/genética , Genes/efectos de la radiación , Mutación , Pentosiltransferasa/genética , Animales , Línea Celular , Cricetinae , Cricetulus , ADN/aislamiento & purificación , Enzimas de Restricción del ADN , Femenino , Peso Molecular , Hibridación de Ácido Nucleico , Ovario
14.
Artículo en Inglés | MEDLINE | ID: mdl-3936327

RESUMEN

Early and late complications of central venous catheterization were investigated in 488 consecutive catheters, 389 introduced in the subclavian vein by a percutaneous puncture technique, 84 by a cut down technique of the cephalic vein, and 15 by a peel away technique. Care and introduction of the catheters was controlled by the parenteral nutrition team in 239 cases. Immediate and late complications were found using both the puncture and venous cut down techniques, but immediate complications differed in the two groups due to the different methods of insertion. The rate of catheter related sepsis (CRS) did not differ significantly when the group under control of the nutrition team was compared with the group without nutritional control (5.9 vs. 6%). The rate of CRS was 1 CRS/220.7 days of therapy in the puncture group and 1 CRS/342.2 days of therapy in the venous cut down group. Catheter tips and blood were cultured from both CRS and non-CRS patients, and the micro-organisms identified. Catheters were withdrawn, under supervision of the nutrition team, for a number of reasons including death, thrombosis, and technical problems, but suspicion of CRS accounted for a high percentage of withdrawals (18% in the puncture group, 16.6% in the venous cut down group). It is suggested that, when CRS is suspected, removal of the catheter should be delayed until all other possibilities have been investigated.


Asunto(s)
Cateterismo/efectos adversos , Nutrición Parenteral , Cateterismo/métodos , Embolia/etiología , Humanos , Neumotórax/etiología , Sepsis/etiología , Vena Subclavia
16.
J Econom ; 23(1): 131-46, 1983 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12312877

RESUMEN

"A state-space model is developed which provides estimates of decrements in a dynamic environment. The model integrates the actual unfolding experience and a priori or Bayesian views of the rates. The estimates of present rates and predicted future rates are continually updated and associated standard errors have simple expressions. The model is described and applied in the context of mortality estimation but it should prove useful in other actuarial applications. The approach is particularly suitable for dynamic environments where data are scarce and updated parameter estimates are required on a regular basis. To illustrate the method it is used to monitor the unfolding mortality experience of the retired lives under an actual pension plan."


Asunto(s)
Anciano , Modelos Teóricos , Mortalidad , Jubilación , Estadística como Asunto , Adulto , Factores de Edad , Demografía , Economía , Empleo , Población , Características de la Población , Dinámica Poblacional , Investigación , Clase Social , Factores Socioeconómicos
20.
Appl Microbiol ; 23(6): 1163-4, 1972 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4626231

RESUMEN

Streptomyces griseus ATCC 10137 synthesizes about 1 IU of L-asparaginase/100 ml of a 4% peptone medium. The enzyme has a pH optimum of 8.5 which is comparable to that of the L-asparaginase derived from Escherichia coli which has antitumor properties.


Asunto(s)
Asparaginasa/biosíntesis , Streptomyces/enzimología , Asparaginasa/metabolismo , Medios de Cultivo , Concentración de Iones de Hidrógeno , Muramidasa , Oxígeno , Peptonas , Streptomyces griseus/enzimología , Streptomyces griseus/crecimiento & desarrollo , Vibración
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