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1.
J Nurs Adm ; 49(1): 12-18, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30499867

RESUMEN

OBJECTIVE: The aim of this study was to construct a sensitizing definition of certification in nursing for research purposes that can provide a foundation from which to further develop a coherent research program building evidence about the impact of certification on healthcare outcomes. BACKGROUND: The lack of a single definition of certification in nursing makes it difficult to draw conclusions about the relationship between specialty certification and patient outcomes. METHODS: This study was guided by the Delphi-Chaffee hybrid methodology proposed by Grant et al. DISCUSSION: Constructing a single, sensitizing definition of certification: 1) provides coherency for direction of certification research; 2) serves as a guide for researchers; and 3) facilitates multimethodological approaches to exploring the relationship among the different components of the definition of certification. CONCLUSION: A sensitizing definition of certification provides an opportunity for researchers to study the relationship between nursing certification and patient outcomes.


Asunto(s)
Certificación/métodos , Certificación/normas , Consenso , Investigación en Enfermería , Especialidades de Enfermería/normas , Técnica Delphi , Humanos
2.
J Nurs Adm ; 48(5): 238-246, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29629910

RESUMEN

OBJECTIVE: To identify how certification is defined, conceptualized, and discussed in the nursing literature. BACKGROUND: Although it is hypothesized that credentialing is associated with better patient outcomes, the evidence is relatively limited. Some authors have suggested that the lack of consistency used to define certification in nursing literature may be one of the dominant obstacles in credentialing research. METHODS: This scoping review was guided by Arksey and O'Malley's framework, and quantitative and qualitative analyses were conducted. RESULTS: The final data set contained a total of 36 articles, of which 14 articles provided a referenced definition of certification. Thematic analysis of the definitions yielded 8 dominant themes. CONCLUSION: The lack of a common definition of certification in nursing must be addressed to advance research into the relationship between certification processes in nursing and healthcare outcomes.


Asunto(s)
Certificación/normas , Educación en Enfermería/normas , Licencia en Enfermería/normas , Especialidades de Enfermería/normas , Canadá , Competencia Clínica , Humanos , Estados Unidos
5.
Artículo en Inglés | MEDLINE | ID: mdl-37466351

RESUMEN

INTRODUCTION: Health professions education often includes teaching observation to inform faculty development (FD) and indirectly improve student performance. Although these FD approaches are well received by faculty, they remain underused and/or underreported, with limited opportunities to receive feedback in workplace contexts. The goal of our study was to map the depth and breadth of education literature on the use of observation of teaching as a tool of professional development in medical education. METHODS: Following the methodology by Arksey and O'Malley, we conducted a scoping review and searched four databases for articles published in English (final searches in April 2022). RESULTS: Of 2080 articles identified, 45 met the inclusion criteria. All observation activities were associated with one of the following FD approaches: peer observation of teaching (23 articles, 51%), peer coaching (12, 27%), peer review (9, 20%), and the critical friends approach (1, 2%). Thirty-three articles (73%) concerned formative versions of the observation model that took place in clinical settings (21, 47%), and they tended to be a voluntary (27, 60%), one-off (18, 40%), in-person intervention (29, 65%), characterized by limited institutional support (13, 29%). Both barriers and challenges of teaching observation were identified. DISCUSSION: This review identified several challenges and shortcomings associated with teaching observation, such as inadequate methodological quality of research articles, inconsistent terminology, and limited understanding of the factors that promote long-term sustainability within FD programs. Practical strategies to consider when designing an FD program that incorporates teaching observation are outlined.

6.
Fam Med ; 53(1): 9-22, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33471918

RESUMEN

BACKGROUND AND OBJECTIVES: The implementation of effective competency-based medical education (CBME) relies on building a coherent and integrated system of assessment across the continuum of training to practice. As such, the developmental progression of competencies must be assessed at all stages of the learning process, including continuing professional development (CPD). Yet, much of the recent discussion revolves mostly around residency programs. The purpose of this review is to synthesize the findings of studies spanning the last 2 decades that examined competency-based assessment methods used in family medicine residency and CPD, and to identify gaps in their current practices. METHODS: We adopted a modified form of narrative review and searched five online databases and the gray literature for articles published between 2000 and 2020. Data analysis involved mixed methods including quantitative frequency analysis and qualitative thematic analysis. RESULTS: Thirty-seven studies met inclusion criteria. Fourteen were formal evaluation studies that focused on the outcome and impact evaluation of assessment methods. Articles that focused on formative assessment were prevalent. The most common levels of educational outcomes were performance and competence. There were few studies on CBME assessment among practicing family physicians. Thematic analysis of the literature identified several challenges the family medicine educational community faces with CBME assessment. CONCLUSIONS: We recommend that those involved in health education systematically evaluate and publish their CBME activities, including assessment-related content and evaluations. The highlighted themes may offer insights into ways in which current CBME assessment practices might be improved to align with efforts to improve health care.


Asunto(s)
Educación Médica , Internado y Residencia , Competencia Clínica , Educación Basada en Competencias , Medicina Familiar y Comunitaria , Humanos , Aprendizaje , Publicaciones
7.
Fam Med ; 52(4): 246-254, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32267519

RESUMEN

BACKGROUND AND OBJECTIVES: While family medicine has been one of the first specialties to implement competency-based medical education (CBME) in residency, the nature and level of its integration with continuing professional development (CPD) is neither well understood nor well studied. The purpose of this review was to examine the current state of CBME implementation in family medicine residency and CPD programs in the North American education literature, with the aim of identifying implementation concepts and strategies that are generalizable to other medical settings to inform the design and implementation of residency training and CPD. METHODS: Using an Arksey and O'Malley six-step framework, we searched five online databases and the gray literature over the period between January 2000 through April 2017. We included full-text articles that focused on the key words CBME, residency, CPD, and family medicine. RESULTS: Of the articles reviewed, 37 met the inclusion criteria and were selected for full review. Eighty six percent of included articles focused on foundation elements related to designing competency-based curriculum and assessment strategies rather than program evaluation or other outcome measures. Only 19% of the articles were related to CPD that focused only on the implementation at the program and/or institution/organization levels. CONCLUSIONS: Given that the implementation of CBME is in its relative infancy, the pattern of implementation activities described in this scoping review reflected a limited focus on a broad range of issues related to fidelity of implementation of this complex intervention.


Asunto(s)
Internado y Residencia , Canadá , Educación Basada en Competencias , Curriculum , Medicina Familiar y Comunitaria , Humanos , Estados Unidos
8.
Acad Med ; 95(7): 1106-1119, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31996559

RESUMEN

PURPOSE: To examine the extent, range, and nature of how competency-based medical education (CBME) implementation terminology is used (i.e., the conceptualization of CBME-related terms) within the family medicine postgraduate medical education (PGME) and continuing professional development (CPD) literature. METHOD: This scoping review's methodology was based on Arksey and O'Malley's framework and subsequent recommendations by Tricco and colleagues. The authors searched 5 databases and the gray literature for U.S. and Canadian publications between January 2000 and April 2017. Full-text English-language articles on CBME implementation that focused exclusively on family medicine PGME and/or CPD programs were eligible for inclusion. A standardized data extraction form was used to collect article demographic data and coding concepts data. Data analysis used mixed methods, including quantitative frequency analysis and qualitative thematic analysis. RESULTS: Of 470 unique articles identified, 80 (17%) met the inclusion criteria and were selected for inclusion in the review. Only 12 (15%) of the 80 articles provided a referenced definition of the coding concepts (i.e., referred to an article/organization as the definition's source), resulting in 19 highly variable-and 12 unique- referenced definitions of key terms used in CBME implementation (competence, competency, competency-based medical education). Thematic analysis of the referenced definitions identified 15 dominant themes, among which the most common were (1) a multidimensional and dynamic concept that encompasses a variety of skill components and (2) being able to use communication, knowledge, technical skills, clinical reasoning, judgment, emotions, attitudes, personal values, and reflection in practice. CONCLUSIONS: The construction and dissemination of shared definitions is essential to CBME's successful implementation. The low number of referenced definitions and lack of consensus on such definitions suggest more attention needs to be paid to conceptual rigor. The authors recommend those involved in family medicine education work with colleagues across medical specialties to develop a common taxonomy.


Asunto(s)
Educación Basada en Competencias/métodos , Formación de Concepto/fisiología , Educación Médica/métodos , Medicina Familiar y Comunitaria/educación , Canadá/epidemiología , Competencia Clínica/normas , Comunicación , Educación Médica Continua/métodos , Emociones/fisiología , Estudios de Evaluación como Asunto , Humanos , Juicio/fisiología , Conocimiento , Publicaciones/tendencias , Prueba de Apercepción Temática/estadística & datos numéricos , Estados Unidos/epidemiología
9.
J Contin Educ Health Prof ; 40(3): 147-157, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32898116

RESUMEN

INTRODUCTION: The authors sought to identify how physician specialty certification is defined in the North American literature. METHODS: A rigorous, established six-stage scoping review framework was used to identify the North American certification literature published between January 2006 and May 2016 relating to physician specialty certification. Data were abstracted using a charting form developed by the study team. Quantitative summary data and qualitative thematic analysis of the purpose of certification were derived from the extracted data. RESULTS: A two stage screening process identified 88 articles that met predefined criteria. Only 14 of the 88 articles (16%) contained a referenced purpose of certification. Eighteen definitions were identified from these articles. Definitional concepts included lifelong learning and continuous professional development, assessment of competence and performance, performance improvement, public accountability, and professional standing. DISCUSSION: Most articles identified in this scoping review did not define certification or describe its purpose or intent. Future studies should provide a definition of certification to further scholarly examination of its intent and effects and inform its further evolution.


Asunto(s)
Certificación/clasificación , Médicos/tendencias , Certificación/tendencias , Humanos , América del Norte , Médicos/clasificación
10.
MedEdPublish (2016) ; 8: 145, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-38440164

RESUMEN

This article was migrated. The article was marked as recommended. There is a growing worldwide awareness in the field of health professions education and research that a successful implementation of competency-based medical education (CBME) requires embracing all stages of professional development (from undergraduate, through residency to continuing education). However, despite increased levels of cognizance and even enthusiasm about the importance of the entire continuum for the ultimate goal of improved healthcare, much work still remains as CBME principles are not widely adopted in continuing professional development (CPD). Much has been written about the process of competency-based curriculum development (e.g., the formation and development of meaningful and measurable outcomes) in undergraduate studies and postgraduate training, but not in CPD. If we expect a CPD curriculum to integrate CBME, competencies must be developed and clearly specified how they will fit into a coherent and implementable curriculum structure. In this article, we describe existing practices some educational institutions have, including our experiences in the Office of CPD at the University of Ottawa, Canada, in designing a competency-based curriculum and provide 12 tips for those who begin their journey of organizing, developing, and implementing such curricula. We conclude that in order to translate a competency-based approach into CPD, educational programs will have to refine curricula across health professionals' education using curriculum mapping as an important tool of curriculum development and evaluation.

11.
Exp Gerontol ; 41(2): 117-22, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16352410

RESUMEN

Reproductive senescence occurs in all female mammals with resultant changes in numerous body functional systems and several important features may be species-specific. Those features that appear to parallel human menopause and aging include general similarity of hormone profiles across the menopausal transition, progression to cycle termination through irregular cycles, declining fertility with age, disturbances in thermogenesis, age-related gains in body weight, fat distribution and disposition towards metabolic syndrome. Structural and hormonal changes in the brain and ovary play a critical role in determining the onset of reproductive senescence. The short life span of rodents such as mice (compared to humans) and the ability to generate specific and timed gene deletions, provide powerful experimental paradigms to understand the molecular and functional changes that precede and follow the loss of reproductive capacity. In theory, any manipulation that compromises ovarian function either partly or totally would impact reproductive events at various levels followed by other dysfunctions. In this article, we provide an overview of three mouse models for the study of female reproductive aging. They are derived from different strategies and their age related phenotypes have been characterized to varying degrees. The follitropin receptor knockout (FORKO) mouse, in its null and haploinsufficient state as well as the dioxin/aryl hydrocarbon receptor (AhR) knockout mouse, serve as two examples of single gene deletions. A third model, using administration of a chemical toxicant such as 4-vinylcyclohexene diepoxide (VCD) in the adult state, produces ovarian deficiencies accompanied by aging changes. These will serve as useful alternatives to previously used radical ovariectomy in young adults. It is anticipated that these new models and more that will be forthcoming will extend opportunities to understand reproductive aging and resolve controversies that abound on issues related to benefits and risks of hormone replacement therapy or other modalities for improving quality of life.


Asunto(s)
Envejecimiento/fisiología , Menopausia/fisiología , Modelos Animales , Animales , Carcinógenos , Ciclohexanos , Ciclohexenos , Contaminantes Ambientales , Femenino , Hormonas Esteroides Gonadales/fisiología , Ratones , Ratones Noqueados , Ratones Mutantes , Ovario/efectos de los fármacos , Compuestos de Vinilo
12.
Fam Med ; 53(5): 390, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34019692
13.
Endocrinology ; 143(9): 3618-27, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12193578

RESUMEN

A fully functional FSH receptor (Fshr) is required for ovarian follicular development and fertility. Fshr null females are sterile because of failure of follicular maturation, ovulation, and estrogen deficiency. Because Fshr-haploinsufficient females also begin to show age-dependent reproductive deficits that mimic biological aging, we have investigated the changes that occur in the uterus of these mice. The uterine weight in 12-month-old Fshr +/- mice increased 2-fold, and most retired breeders (those that stopped breeding earlier than our wild-type females) developed unilateral uterine masses that appeared similar to several abnormalities that also occur in women and associated with infertility. Curiously, there was a tendency for most of the abnormality to occur in the right horn. Up to 25% of the virgin Fshr-haploinsufficient mice also developed pathology. These transformations were not present in either wild-type mice or the estrogen-deficient Fshr null females at any age. In haploinsufficient females, estrogen and progesterone were reduced and testosterone was elevated in circulation by 1 yr. Fshr-haploinsufficient mice developed an imbalance of progesterone receptor isoforms A and B in the uterus. This alteration of progesterone receptors along with an increase in LH receptors in the uterus may contribute to the induction of high frequency of uterine pathology. Angiogenesis, vascular abnormality, and adenomyosis appeared to be increased in the uterine horn bearing pathological mass. The Fshr-haploinsufficient mice might help in understanding the molecular basis of induction of uterine pathology and tissue patterning.


Asunto(s)
Envejecimiento , Heterocigoto , Receptores de HFE/deficiencia , Receptores de HFE/genética , Útero/patología , Animales , Endometriosis/genética , Endometriosis/patología , Estradiol/sangre , Ciclo Estral , Femenino , Reabsorción del Feto/genética , Infertilidad Femenina/genética , Masculino , Ratones , Ratones Noqueados , Neovascularización Patológica , Tamaño de los Órganos , Embarazo , Progesterona/sangre , Receptores de HL/análisis , Receptores de HL/metabolismo , Receptores de Progesterona/análisis , Receptores de Progesterona/metabolismo , Testosterona/sangre , Útero/irrigación sanguínea , Útero/química
14.
Neuroreport ; 14(12): 1617-22, 2003 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-14502087

RESUMEN

Progressive and long-term sex hormone imbalance in the FSH-R haploinsufficient menopausal mouse leads to degenerative changes in the CNS associated with increased anxiety. The brain region most affected by aging in these mice is the hippocampus. Choline acetyltransferase (ChAT) enzymatic activity and synapsin immunoreactivity are reduced at 20 months of age. Neurons in the dentate gyrus show signs of progressive degenerative changes, hypertrophy and glyosis, and subsequent cell shrinkage and death. These results suggest that the menopausal mouse mimics degenerative changes in the hippocampus of hormonally imbalanced aging humans. We propose using this animal model to test the effectiveness of potential therapeutics in paradigms of accelerated aging.


Asunto(s)
Envejecimiento , Sistema Nervioso Central/metabolismo , Hormonas Esteroides Gonadales , Menopausia , Modelos Animales , Receptores de HFE/deficiencia , Envejecimiento/sangre , Envejecimiento/patología , Envejecimiento/psicología , Animales , Ansiedad/sangre , Ansiedad/patología , Ansiedad/psicología , Sistema Nervioso Central/patología , Estradiol/sangre , Femenino , Hormonas Esteroides Gonadales/sangre , Menopausia/sangre , Menopausia/psicología , Ratones , Degeneración Nerviosa/sangre , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/patología , Receptores de HFE/genética , Testosterona/sangre
15.
J Reprod Med ; 47(5): 412-8, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12063881

RESUMEN

OBJECTIVE: To evaluate how chronically estrogen deficient female FORKO mice with genetic disruption of the FSH receptor respond to estrogen therapy. STUDY DESIGN: Subcutaneous estrogen agonist or antagonist therapy was initiated to study reproductive tissue response, adipose tissue mass and plasma lipid profiles. RESULTS: Within 36-48 hours of agonist administration, the classic measures of estrogenic activity were evident in the uterus and vagina. Older animals also responded to therapy during a 10-day period, indicating that estrogen receptor signaling systems are unaffected by aging. In these obese mutants, this short treatment decreased adipose tissue in all areas and corrected lipid abnormalities. Tamoxifen, a nonsteroidal mixed estrogen agonist and antagonist, had marginal effects on the uterus and body fat of FORKO mice, indicating differences in interaction. CONCLUSION: In FORKO mice lacking ovarian estrogen, the receptors remain fully functional. Hence, this is a useful model for studying estrogen replacement therapy and helps resolve questions related to efficacy and actions.


Asunto(s)
Modelos Animales de Enfermedad , Estradiol/farmacología , Antagonistas de Estrógenos/farmacología , Terapia de Reemplazo de Estrógeno , Tamoxifeno/farmacología , Tejido Adiposo/efectos de los fármacos , Animales , Apolipoproteínas E/sangre , Colesterol/sangre , HDL-Colesterol/sangre , Estradiol/sangre , Femenino , Ratones , Ratones Noqueados , Modelos Genéticos , Receptores de HFE/deficiencia , Receptores de HFE/genética , Testosterona/sangre , Triglicéridos/sangre , Útero/efectos de los fármacos , Vagina/efectos de los fármacos
16.
J Public Health Policy ; 31(1): 30-50, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20200524

RESUMEN

The present study examines how growing socio-economic inequalities in transitional countries that have followed different health policy paths affect women's access to reproductive health care. I conducted surveys in Kazakhstan and Belarus and used logistic regression analyses to determine accessibility to and satisfaction with reproductive health services, reproductive status, and reproductive history based on country of residence. By all measures, access to reproductive health services was most problematic for the low-income women in Kazakhstan but to a significantly lesser extent for economically disadvantaged respondents in Belarus. Differences in education had a significant effect on women's access to reproductive health services in Kazakhstan but were not present in Belarus. Household income was the most powerful predictor of self-perceived health in Kazakhstan, but not in Belarus. The unreformed health-care system in Belarus appears to be more accessible for all women than Kazakhstan's health-care system that underwent significant market-oriented reform.


Asunto(s)
Disparidades en Atención de Salud , Servicios de Salud Reproductiva , Adolescente , Adulto , Estudios Transversales , Femenino , Accesibilidad a los Servicios de Salud , Humanos , Kazajstán , Modelos Logísticos , Persona de Mediana Edad , República de Belarús , Clase Social , Adulto Joven
17.
Obesity (Silver Spring) ; 14(7): 1142-54, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16899795

RESUMEN

OBJECTIVE: To investigate the relationship of early obesity to metabolic syndrome during sex hormonal imbalances in mutant female mice at different ages. RESEARCH METHODS AND PROCEDURES: Hormonal imbalances, accumulation and nature of adipose tissue, food intake, glucose tolerance, and expression of candidate genes and markers of inflammation were studied by comparing wild-type, null, and haploinsufficient follitropin receptor knockout female mice at different ages. RESULTS: Follitropin receptor deletion in mice produced null females that are infertile and haploinsufficient mice that undergo accelerated biological aging. Both types of mutants with sex hormonal imbalances have central obesity without hyperphagia, but circulating leptin is elevated. Adipocyte hyperplasia and hypertrophy is attributed to elevated peroxisome proliferator-activated receptor gamma expression. Adiponectin protein levels increase in fat tissue and plasma. Only mutants but not controls acquire age-dependent decline in glucose tolerance with high insulin and altered pancreatic beta cells. Changes in inflammation markers, decreased muscle insulin receptor phosphorylation, and increase of the enzyme protein tyrosine phosphatase 1B indicate insulin resistance. DISCUSSION: In this animal model, the chronological appearance of early obesity induced by hormonal imbalances culminates in characteristics that are attributable to metabolic syndrome, including cardiovascular abnormalities. Dissection of the depot-specific alterations and defining molecular interrelationships could help in developing targeted remedies and resolving complications and controversies related to health benefits and adversities of current hormone replacement therapy.


Asunto(s)
Tejido Adiposo/metabolismo , Envejecimiento/genética , Regulación de la Expresión Génica , Hormonas Esteroides Gonadales/fisiología , Síndrome Metabólico/genética , Obesidad/genética , PPAR gamma/metabolismo , Adiponectina/sangre , Envejecimiento/fisiología , Animales , Modelos Animales de Enfermedad , Femenino , Hormona Folículo Estimulante/metabolismo , Prueba de Tolerancia a la Glucosa , Hormonas Esteroides Gonadales/genética , Hormonas Esteroides Gonadales/metabolismo , Inflamación , Resistencia a la Insulina , Péptidos y Proteínas de Señalización Intercelular , Leptina/sangre , Síndrome Metabólico/metabolismo , Ratones , Ratones Noqueados , Obesidad/metabolismo , Receptores de HFE/genética
18.
Endocrine ; 26(3): 219-26, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16034175

RESUMEN

This review highlights observations gleaned from recent reports on the deletion of FSH and LH receptors in mice. Gonadal differentiation does not depend on the presence of gonadotropin receptors but development is affected to varying degrees in both sexes. In both knockouts the null females are infertile with severely underdeveloped gonads and accessory structures. Sexual maturity and/or pubertal delay occur depending on the sex and knockout. Male null FSH-R mice have reduced fertility but null LH-R males are sterile due to cryptorchid testes and deficient spermatogenesis. In null FSH-R females hormonal imbalances are due to deficient estrogen and hyperandrogenemia. LH-R deficient females have low estrogen and testosterone. Females in both knockouts display phenotypes such as obesity, bone deficiency, and changes in brain structure and function in addition to manifestation of different types of reproductive tract tumors. Both types of mice represent good models for testing hormone replacement therapy in different combinations. The FSH-R heterozygous females could also be useful for studying age-dependent phenotypes.


Asunto(s)
Marcación de Gen , Receptores de HFE/genética , Receptores de HL/genética , Reproducción/genética , Animales , Femenino , Fertilidad/genética , Ingeniería Genética , Masculino , Ratones , Ratones Noqueados , Modelos Animales , Factores Sexuales , Transducción de Señal/genética
19.
Biol Reprod ; 67(2): 361-9, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12135868

RESUMEN

Female mice that are null for the FSH-receptor (FSH-R) gene are estrogen deficient, acyclic, and sterile. However, the heterozygous (+/-) mice initially have reduced fertility and stop breeding by 7-9 mo. The purpose of this study was to understand the basis of reduced fertility in mice with haploinsufficiency of the FSH-R. Heterozygous females were compared to +/+ females at 3, 7, and 12 mo of age. By 7 mo most of the +/- females were acyclic and <50% delivered pups. The wild-type females were normal in these respects. None of the 1-yr-old +/- females gave viable offspring (73% in +/+). Many degenerative changes, including atresia and apoptosis, and profound loss of oocytes, were apparent in +/- mice by 7 mo. The 1-yr-old +/- ovary had very few follicles and consisted mostly of fibroid tissue and cysts. Our data support the hypothesis that reproductive deficits in +/- FSH-R mice occur because of accelerated oocyte loss due to increased cell death in the ovary. These events contribute to early reproductive senescence and biological aging in mice. Thus FSH-R status is an important determinant of ovarian aging and all phenomena that arise from subsequent estrogen deficiency and other aberrations.


Asunto(s)
Envejecimiento/genética , Envejecimiento/fisiología , Oocitos/fisiología , Receptores de HFE/genética , Reproducción/genética , Reproducción/fisiología , Animales , Peso Corporal/genética , Peso Corporal/fisiología , Fragmentación del ADN/genética , Fragmentación del ADN/fisiología , Ciclo Estral/genética , Ciclo Estral/fisiología , Femenino , Fertilidad/genética , Fertilidad/fisiología , Atresia Folicular/genética , Atresia Folicular/fisiología , Haplotipos , Etiquetado Corte-Fin in Situ , Infertilidad Femenina/genética , Infertilidad Femenina/metabolismo , Ratones , Folículo Ovárico/citología , Folículo Ovárico/fisiología , Ovario/citología , Ovario/fisiología , Maduración Sexual/genética , Maduración Sexual/fisiología
20.
Biol Reprod ; 66(6): 1656-66, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12021044

RESUMEN

The FSH receptor (FSHR) is selectively expressed in the granulosa and Sertoli cells in a development-dependent manner. Little is known regarding how the regulatory factors balance expression of this gene in ovarian cycles or spermatogenic stages. We have used the ovine FSHR promoter as a model system and identified a third regulatory element (RE-3) located at -197 to -171 of the strongest promoter. Gel mobility shift and antibody supershift assays demonstrated that nuclear factors c-Fos/c-Jun, steroidogenic factor-1 (SF-1), upstream stimulatory factor-1/2 (USF-1/2), and chicken ovalbumin upstream promoter transcription factor-1/2 (COUP-TFI/II) potentially bound to RE-3. We have also extended our previous observations by showing that a sequence containing an E-box was not only bound by USF proteins but also recognized by COUP-TF orphan receptors. Functional studies demonstrated that USF-1/2, c-Fos/c-Jun, and SF-1 were activators, whereas COUP-TFs were repressors. Our studies indicated that RE-3 mediated SF-1 activation as well as phorbol 12-myristate 13-acetate stimulation, whereas COUP-TFs inhibited AP-1, USFs, and SF-1 activation. We also demonstrated that both COUP-TF-binding sites in the core promoter were required for the bipartite elements to oppose their competitor binding. These data suggest a mechanism by which positive and negative regulators compete for the common regulatory elements, providing antagonistic pathways that might govern the expression of FSHR in gonadal cells.


Asunto(s)
Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/farmacología , Receptores de HFE/genética , Receptores de Esteroides , Factor de Transcripción AP-1/antagonistas & inhibidores , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/farmacología , Animales , Sitios de Unión , Factor de Transcripción COUP I , Factores de Transcripción COUP , Línea Celular , ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Femenino , Factores de Transcripción Fushi Tarazu , Expresión Génica/efectos de los fármacos , Células de la Granulosa , Proteínas de Homeodominio , Inmunohistoquímica , Ratones , Mutagénesis Sitio-Dirigida , Regiones Promotoras Genéticas , Receptores Citoplasmáticos y Nucleares , Secuencias Reguladoras de Ácidos Nucleicos , Ovinos , Factor Esteroidogénico 1 , Porcinos , Acetato de Tetradecanoilforbol/farmacología , Factor de Transcripción AP-1/fisiología , Factores de Transcripción/genética , Factores de Transcripción/fisiología , Transfección , Factores Estimuladores hacia 5'
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