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1.
J Health Organ Manag ; ahead-of-print(ahead-of-print)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34455733

RESUMO

PURPOSE: Nurses working during the coronavirus disease 2019 (COVID-19) pandemic have reported elevated levels of anxiety, burnout and sleep disruption. Hospital administrators are in a unique position to mitigate or exacerbate stressful working conditions. The goal of this study was to capture the recommendations of nurses providing frontline care during the pandemic. DESIGN/METHODOLOGY/APPROACH: Semi-structured interviews were conducted during the first wave of the COVID-19 pandemic, with 36 nurses living in Canada and working in Canada or the United States. FINDINGS: The following recommendations were identified from reflexive thematic analysis of interview transcripts: (1) The nurses emphasized the need for a leadership style that embodied visibility, availability and careful planning. (2) Information overload contributed to stress, and participants appealed for clear, consistent and transparent communication. (3) A more resilient healthcare supply chain was required to safeguard the distribution of equipment, supplies and medications. (4) Clear communication of policies related to sick leave, pay equity and workload was necessary. (5) Equity should be considered, particularly with regard to redeployment. (6) Nurses wanted psychological support offered by trusted providers, managers and peers. PRACTICAL IMPLICATIONS: Over-reliance on employee assistance programmes and other individualized approaches to virtual care were not well-received. An integrative systems-based approach is needed to address the multifaceted mental health outcomes and reduce the deleterious impact of the COVID-19 pandemic on the nursing workforce. ORIGINALITY/VALUE: Results of this study capture the recommendations made by nurses during in-depth interviews conducted early in the COVID-19 pandemic.


Assuntos
Esgotamento Profissional/psicologia , COVID-19/enfermagem , Recursos Humanos de Enfermagem no Hospital/psicologia , Serviços de Saúde do Trabalhador , Estresse Psicológico/psicologia , Adulto , Esgotamento Profissional/prevenção & controle , Canadá , Comunicação , Feminino , Humanos , Entrevistas como Assunto , Liderança , Masculino , Determinação de Necessidades de Cuidados de Saúde , Política Organizacional , Pandemias , Equipamento de Proteção Individual , SARS-CoV-2 , Licença Médica , Estresse Psicológico/prevenção & controle , Estados Unidos , Carga de Trabalho
2.
Prog Transplant ; 30(4): 365-367, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32912114

RESUMO

Lung transplantation has evolved to become an acceptable therapy for individuals with end-stage lung disease. Readmissions rates after lung transplantation remain high as compared to other medical surgical populations. The purpose of this review is to synthesize the current body of knowledge about patterns, risk factors, and outcomes of readmissions after lung transplantation. The literature revealed that the most common admission diagnoses linked to lung transplant readmissions are infections followed by tachyarrhythmias, airway complications, surgical complications, rejection, thromboembolic events, gastrointestinal complications, and renal dysfunction. Risk factors for these readmissions include male gender, longer intensive care unit stay, reintubation, prolonged chest tube air leak, frailty, and discharge to a long-term care facility. Outcomes of multiple readmissions after lung transplantation are associated with decreased survival and increased risk of mortality. Further research is needed to better understand which readmission diagnoses are preventable and whether multidisciplinary interventions can reduce readmission rates among patients after lung transplantation.

3.
West J Nurs Res ; 42(10): 829-837, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32075545

RESUMO

Clinical judgment, one's ability to think like a nurse, is an essential skill for safe nursing practice. With the rise of simulation to replace clinical experiences, there is limited evidence regarding the effectiveness of simulation on the development of clinical judgment. This study explored differences in clinical judgment in maternal-newborn courses between undergraduate nursing students participating exclusively in simulation and those participating in hospital-based clinical experiences. Following completion of the clinical rotation, students participated in an evaluative maternal-newborn high-fidelity simulation experience that was recorded and evaluated using the Lasater's Clinical Judgment Rubric (2007). Lasater's Clinical Judgment Rubric scores between the simulation and clinical practice groups were compared using an independent sample t-test. There was no statistical difference in clinical judgment scores between the simulation and hospital-based clinical groups (t = -1.056, P = .295). Our findings suggest that simulation may be a comparable alternative to clinical experience in nursing education.


Assuntos
Competência Clínica/normas , Enfermagem Materno-Infantil/educação , Estudantes de Enfermagem/estatística & dados numéricos , Adolescente , Adulto , Competência Clínica/estatística & dados numéricos , Currículo/tendências , Bacharelado em Enfermagem/métodos , Bacharelado em Enfermagem/estatística & dados numéricos , Avaliação Educacional/métodos , Feminino , Treinamento com Simulação de Alta Fidelidade , Humanos , Masculino , Enfermagem Materno-Infantil/métodos , Enfermagem Materno-Infantil/estatística & dados numéricos , Pessoa de Meia-Idade
4.
J Midwifery Womens Health ; 64(4): 427-434, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31298482

RESUMO

INTRODUCTION: To explore the effect of prepregnancy body mass index (BMI) and gestational weight gain on postpartum weight retention in nulliparous women and weight-for-length percentiles of offspring to 2 years following birth. METHODS: A retrospective secondary analysis of a large, prospective longitudinal study of women conducted during pregnancy and after their first birth was completed to examine outcomes associated with postpartum weight retention. A chart review of the offspring of these women was completed to explore the relationship between maternal prepregnancy BMI and gestational weight gain on offspring weight-for-length percentiles. RESULTS: Data from 652 woman-infant dyads were available for analysis. Average postpartum weight retention was 4.0 kg at one year for all groups. At 6 weeks postpartum, women who were obese prior to pregnancy retained significantly less weight than did women who were normal weight prior to pregnancy (P < .05). Women who were normal weight or overweight at the onset of pregnancy and had gestational weight gain within Institute of Medicine recommendations retained significantly less weight at 6 weeks, 6 months, and 1 year postpartum (P < .01) when compared with women in those same weight groups who had a gestational weight gain in excess of the recommended guideline. Women who entered pregnancy obese and who had a gestational weight gain within the recommended weight range during pregnancy retained significantly less weight compared with women who were obese and who gained in excess of the guideline at 6 weeks postpartum only (P < .05). No statistically significant differences were seen in offspring weight-for-length percentiles at any time point based on maternal prepregnancy BMI or weight gain within guidelines. DISCUSSION: Many women retained weight up to one year postpartum. In this study, we saw no statistically significant differences between the prepregnant BMI groups or between gestational weight gain within guidelines or in excess of guidelines on offspring weight-for-length percentiles.


Assuntos
Ganho de Peso na Gestação , Paridade , Adulto , Estatura , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Lactente , Estudos Longitudinais , Obesidade Materna , Gravidez , Estudos Retrospectivos
5.
JBI Database System Rev Implement Rep ; 17(6): 1086-1091, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31082939

RESUMO

REVIEW OBJECTIVE: This review seeks to establish the current state of knowledge regarding physical assessment skills taught in nursing programs globally. It aims to explore the literature on physical assessment skills taught in nursing curricula globally, skills used by nurses in practice, skills used by students, and core physical assessment skills that are important to teach nursing students.


Assuntos
Competência Clínica , Currículo , Educação em Enfermagem , Avaliação em Enfermagem/normas , Humanos , Estudantes de Enfermagem
6.
Breastfeed Med ; 13(5): 371-380, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29782187

RESUMO

INTRODUCTION: Mothers and infants are at high risk for inadequate vitamin D status. Mechanisms by which vitamin D may affect maternal and infant DNA methylation are poorly understood. OBJECTIVE: This study quantified the effects of vitamin D3 supplementation on DNA methylation in pregnant and lactating women and their breastfed infants. MATERIALS AND METHODS: In this randomized controlled pilot study, pregnant women received vitamin D3 400 international units (IU) (n = 6; control) or 3,800 IU (n = 7; intervention) daily from late second trimester through 4-6 weeks postpartum. Epigenome-wide DNA methylation was quantified in leukocytes collected from mothers at birth and mother-infant dyads at 4-6 weeks postpartum. RESULTS: At birth, intervention group mothers showed DNA methylation gain and loss at 76 and 89 cytosine-guanine (CpG) dinucleotides, respectively, compared to controls. Postpartum, methylation gain was noted at 200 and loss at 102 CpGs. Associated gene clusters showed strongest biologic relevance for cell migration/motility and cellular membrane function at birth and cadherin signaling and immune function at postpartum. Breastfed 4-6-week-old infants of intervention mothers showed DNA methylation gain and loss in 217 and 213 CpGs, respectively, compared to controls. Genes showing differential methylation mapped most strongly to collagen metabolic processes and regulation of apoptosis. CONCLUSIONS: Maternal vitamin D supplementation during pregnancy and lactation alters DNA methylation in mothers and breastfed infants. Additional work is needed to fully elucidate the short- and long-term biologic effects of vitamin D supplementation at varying doses, which could hold important implications for establishing clinical recommendations for prenatal and offspring health promotion.


Assuntos
Aleitamento Materno , Colecalciferol/administração & dosagem , Metilação de DNA , Suplementos Nutricionais , Vitaminas/administração & dosagem , Adulto , Ilhas de CpG , Método Duplo-Cego , Epigenômica , Feminino , Estudo de Associação Genômica Ampla , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Lactação/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Projetos Piloto , Gravidez
7.
J Obstet Gynecol Neonatal Nurs ; 46(1): 135-147, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27840206

RESUMO

OBJECTIVE: To identify the combined effect of prenatal and postnatal vitamin D3 supplementation on the vitamin D status of pregnant and lactating women and their exclusively breastfed infants. DESIGN: Double-blind, randomized controlled trial. SETTING: Upper Midwestern U.S., hospital-based obstetric practice. PARTICIPANTS: Pregnant women (N = 13) planning to exclusively breastfeed were randomized at 24 to 28 weeks gestation to receive vitamin D3 at a dosage of 400 IU (control group, n = 6) or 3,800 IU (intervention group, n = 7) daily through 4 to 6 weeks postpartum. Vitamin D status was determined at enrollment and in mother-infant dyads at 24 to 72 hours after birth and 4 to 6 weeks postpartum. METHODS: Serum 25-hydroxyvitamin D levels were measured to determine the effect of vitamin D3 supplementation on the vitamin D status of mothers and infants. Analysis of covariance was used to compare differences in 25-hydroxyvitamin D levels between the control and intervention groups. RESULTS: The mothers' vitamin D levels were significantly higher in the intervention group than in the control group at birth (p = .044) and at 4 to 6 weeks postpartum (p = .002). Infants in the intervention group had significantly higher vitamin D levels at birth (p = .021) and nonsignificant, clinically relevant increases at 4 to 6 weeks of age (p = .256). No differences were found between maternal groups in serum calcium or parathyroid hormone levels. CONCLUSION: Prenatal to postpartum vitamin D3 supplementation is an effective intervention to increase a mother's vitamin D status and to promote optimal vitamin D status in newborns and exclusively breastfed infants.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Suplementos Nutricionais , Vitamina D/análogos & derivados , Vitamina D/administração & dosagem , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Fenômenos Fisiológicos da Nutrição Materna , Gravidez
8.
Biol Res Nurs ; 17(4): 438-43, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25964656

RESUMO

The primary risk factor for neonatal Group B streptococcus (GBS) infection, which is the leading cause of infectious neonatal morbidity and mortality, is maternal colonization. However, no definitive maternal risk factors for GBS colonization have been identified and no systematic efforts have been made to prevent maternal colonization. The purpose of this exploratory secondary analysis was to evaluate genome-wide DNA methylation patterns in maternal peripheral blood early in pregnancy for association with GBS colonization status in the third trimester. Genome-wide DNA methylation was analyzed from 18 nulliparous GBS-positive and -negative women (n = 9/group) recruited for a previous study. No statistically significant differences in baseline characteristics or DNA methylation in peripheral blood were identified between GBS-positive and -negative women in early pregnancy. The results suggest that DNA methylation patterns in peripheral blood are not associated with risk for GBS colonization.


Assuntos
Metilação de DNA , Complicações Infecciosas na Gravidez/genética , Infecções Estreptocócicas/genética , Streptococcus agalactiae/genética , Adulto , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Resultado da Gravidez , Terceiro Trimestre da Gravidez/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Análise de Sequência de DNA , Infecções Estreptocócicas/diagnóstico
9.
Life Sci ; 129: 10-5, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25050465

RESUMO

AIMS: As maternal vitamin D status has been associated with preeclampsia, the purpose of this study was to determine variations in DNA methylation patterns and associated protein expression in placental genes regulating vitamin D metabolism. MAIN METHODS: A convenience sample of 48 pregnant nulliparous women, including 11 later diagnosed with preeclampsia, were recruited in this prospective study. Using a case-control design in two groups of women, we administered a food frequency questionnaire to determine vitamin D dietary intake. Laboratory measures included serum vitamin D levels (25[OH]D), DNA methylation patterns and protein expression in placental genes regulating vitamin D metabolism (1α-hydroxylase, CYP27B1; vitamin D receptor, VDR; retinoid X receptor, RXR) from placental tissue collected at delivery among those diagnosed with preeclampsia and those who remained normotensive throughout pregnancy. KEY FINDINGS: There were no significant differences in vitamin D dietary intake or mean serum 25[OH]D levels, although the proportion of women with deficient 25[OH]D levels was higher in the preeclampsia group (46%) than the normotensive group (20%). Placenta samples from women with preeclampsia also had increased DNA methylation of CYP27B1, VDR and RXR genes with lower protein expression levels limited to RXR. SIGNIFICANCE: Hypermethylation of key placental genes involved in vitamin D metabolism suggests uncoupling of processes that may interfere with placentation and availability of vitamin D at the maternal-fetal interface.


Assuntos
Metilação de DNA/fisiologia , Regulação da Expressão Gênica/fisiologia , Paridade/fisiologia , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Vitamina D/sangue , Adulto , Estudos de Casos e Controles , Epigenômica/métodos , Feminino , Humanos , North Dakota , Gravidez , Resultado da Gravidez , Vitamina D/administração & dosagem
10.
Biol Res Nurs ; 16(4): 409-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24165327

RESUMO

BACKGROUND: Preeclampsia contributes significantly to pregnancy-associated morbidity and mortality as well as future risk of cardiovascular disease in mother and offspring, and preeclampsia in offspring. The lack of reliable methods for early detection limits the opportunities for prevention, diagnosis, and timely treatment. PURPOSE: The purpose of this study was to explore distinct DNA methylation patterns associated with preeclampsia in both maternal cells and fetal-derived tissue that represent potential biomarkers to predict future preeclampsia and inheritance in children. METHOD: A convenience sample of nulliparous women (N = 55) in the first trimester of pregnancy was recruited for this prospective study. Genome-wide DNA methylation was quantified in first-trimester maternal peripheral white blood cells and placental chorionic tissue from normotensive women and those with preeclampsia (n = 6/group). RESULTS: Late-onset preeclampsia developed in 12.7% of women. Significant differences in DNA methylation were identified in 207 individual linked cytosine and guanine (CpG) sites in maternal white blood cells collected in the first trimester (132 sites with gain and 75 sites with loss of methylation), which were common to approximately 75% of the differentially methylated CpG sites identified in chorionic tissue of fetal origin. CONCLUSION: This study is the first to identify maternal epigenetic targets and common targets in fetal-derived tissue that represent putative biomarkers for early detection and heritable risk of preeclampsia. Findings may pave the way for diagnosis of preeclampsia prior to its clinical presentation and acute damaging effects, and the potential for prevention of the detrimental long-term sequelae.


Assuntos
Biomarcadores/sangue , Metilação de DNA , Pré-Eclâmpsia/sangue , Adulto , Ilhas de CpG , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Adulto Jovem
11.
J Midwifery Womens Health ; 58(4): 423-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23895215

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the relationships between first-trimester dietary factors and biochemical measures and subsequent risk of gestational hypertension. METHODS: This pilot study used a prospective design utilizing a convenience sample of nulliparous women enrolled at their first prenatal visit. A total of 57 women completed the study. Participants were divided into 2 groups for data analysis: normotensive pregnancy and gestational hypertension. RESULTS: Nearly one-quarter of study participants (22.8%) developed gestational hypertension, of whom 84.6% had significant proteinuria meeting the criteria for preeclampsia. There were no significant differences in micronutrient or macronutrient dietary intakes between groups. Serum iron and zinc levels were lower for the gestational hypertension group compared with the normotensive pregnancy group (P ≤ .01). Low serum zinc levels were related to a risk of developing gestational hypertension (adjusted odds ratio, 0.930; 95% confidence interval, 0.872-0.992). DISCUSSION: Ensuring adequate intake of zinc and monitoring serum zinc levels in nulliparous pregnant women may help to prevent or contribute to early detection of gestational hypertension.


Assuntos
Deficiências Nutricionais/complicações , Dieta , Hipertensão Induzida pela Gravidez/etiologia , Estado Nutricional , Primeiro Trimestre da Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal , Zinco/deficiência , Adulto , Biomarcadores/sangue , Deficiências Nutricionais/sangue , Ingestão de Energia , Feminino , Humanos , Hipertensão Induzida pela Gravidez/sangue , Hipertensão Induzida pela Gravidez/epidemiologia , Ferro/sangue , Razão de Chances , Paridade , Projetos Piloto , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/etiologia , Pré-Eclâmpsia/urina , Gravidez , Cuidado Pré-Natal , Prevalência , Estudos Prospectivos , Proteinúria/epidemiologia , Proteinúria/etiologia , Valores de Referência , Fatores de Risco , Adulto Jovem , Zinco/sangue
12.
Nurs Outlook ; 61(4): 235-241.e4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23849553

RESUMO

DNA methylation is an epigenomic modification that is essential to normal human development and biological processes. DNA methylation patterns are heritable and dynamic throughout the life span. Environmental exposures can alter DNA methylation patterns, contributing to the development of complex disease. Identification and modulation of environmental factors influencing disease susceptibility through alterations in DNA methylation are amenable to nursing intervention and form the basis for individualized patient care. Here we describe the evidence supporting the translation of DNA methylation analyses as a tool for screening, diagnosis, and treatment of complex disease in nursing research and practice. The ethical, legal, social, and economic considerations of advances in genomics are considered as a model for epigenomic policy. We conclude that contemporary and informed nurse scientists and clinicians are uniquely poised to apply innovations in epigenomic research to clinical populations and develop appropriate policies that guide equitable and ethical use of new strategies to improve patient care.


Assuntos
Metilação de DNA , Doença/genética , Epigênese Genética , Interação Gene-Ambiente , Humanos , Cuidados de Enfermagem , Política Pública , Pesquisa Médica Translacional
13.
Clin J Oncol Nurs ; 15(6): E114-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22119986

RESUMO

Diet may play a significant role in cancer prevention, disease progression, and treatment tolerance. An in-depth search of the literature revealed limited information geared toward nurses about diet assessment methods used in research. The purpose of this review is to synthesize the evidence regarding diet assessment methods important in oncology studies. The method used varied based on the study size, duration, and research question. For example, studies focusing on mean nutrient intake of a group used a 24-hour dietary recall, estimated food diary or dietary record, or food frequency questionnaire. Studies investigating usual nutrient intake predominately used multiple 24-hour dietary recalls, dietary records, biomarkers, or food frequency questionnaires. Measuring dietary intake accurately in a cost-effective manner is a difficult task. Selection of the appropriate assessment tool is critical for the generation of quality data. Oncology nurses are increasing their involvement in nutrition research, and the findings from this review may promote a better understanding of the published and ongoing research in this important field of study.


Assuntos
Neoplasias/enfermagem , Avaliação Nutricional , Enfermagem Oncológica , Registros de Dieta , Humanos , Inquéritos e Questionários , Recursos Humanos
14.
Prostate ; 59(3): 337-49, 2004 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15042610

RESUMO

BACKGROUND: Currently, the main obstacle to curing advanced prostate cancer is development of androgen independence (AI), where malignant cells acquire the ability to survive in the absence of androgens. Our initial experimental approach used cDNA microarrays to characterize changes in gene expression in the LNCaP human prostate tumor model during progression to AI. The transcription factor Y-box binding protein (YB-1) was shown to be one of the genes upregulated. We focused on increased YB-1 expression during progression in clinical specimens, and further examined one of its downstream targets, P-glycoprotein (P-gp). METHODS: Northern blot analysis was performed on LNCaP tumor series, as well as immunohistochemical analyses of human prostate cancer tissue samples. YB-1 was transiently transfected and transport analysis were performed to analyze P-gp efflux activity. RESULTS: YB-1 expression is markedly increased during benign to malignant transformation and further following androgen ablation. In addition, increased YB-1 expression after castration in the LNCaP model is linked to upregulation of P-gp. We demonstrate that YB-1 upregulates P-gp activity resulting in a 40% intracellular decrease in the P-gp substrate vinblastine. We have also found that P-gp increases the efflux of the endogenous androgen, dihydrotestosterone (DHT), from prostate cells and leads to decreased androgen regulated gene expression. CONCLUSIONS: We hypothesize that early in prostate cancer progression, increased expression of YB-1 may increase P-gp activity which may in turn lower androgen levels in the prostate tumor cells. Suppression of androgen levels may activate cell survival pathways and lead to an adaptive survival advantage of androgen independent prostate cancer cells following androgen ablation therapy.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/farmacologia , Proteínas Estimuladoras de Ligação a CCAAT/biossíntese , Sobrevivência Celular , Transformação Celular Neoplásica , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Fatores de Transcrição/biossíntese , Antagonistas de Androgênios/farmacologia , Androgênios/farmacologia , Northern Blotting , Progressão da Doença , Humanos , Imuno-Histoquímica , Masculino , Fatores de Transcrição NFI , Análise de Sequência com Séries de Oligonucleotídeos , Regulação para Cima , Proteína 1 de Ligação a Y-Box
15.
Environ Health Perspect ; 111(4): 461-6, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12676599

RESUMO

Hexachlorobenzene (HCB) is a persistent environmental contaminant that has the potential to interfere with steroid hormone regulation. The prostate requires precise control by androgens to regulate its growth and function. To determine if HCB impacts androgen action in the prostate, we used a number of methods. Our in vitro cell-culture-based assay used a firefly luciferase reporter gene driven by an androgen-responsive promoter. In the presence of dihydrotestosterone, low concentrations (0.5-5 nM) of HCB increased the androgen-responsive production of firefly luciferase and high concentrations of HCB (> 10 microM) suppressed this transcriptional activity. Results from a binding assay showed no evidence of affinity between HCB and the androgen receptor. We also tested HCB for in vivo effects using transgenic mice in which the transgene was a prostate-specific, androgen-responsive promoter upstream of a chloramphenicol acetyl transferase (CAT) reporter gene. In 4-week-old mice, the proportion of dilated prostate acini, a marker of sexual maturity, increased in the low HCB dose group and decreased in the high HCB dose mice. In the 8-week-old mice, there was a significant decrease in both CAT activity and prostate weight upon exposure to 20 mg/kg/day HCB. Therefore, in vitro and in vivo data suggest that HCB weakly agonizes androgen action, and consequently, low levels of HCB enhanced androgen action but high levels of HCB interfered. Environmental contaminants have been implicated in the rising incidence of prostate cancer, and insight into the mechanisms of endocrine disruption will help to clarify their role.


Assuntos
Androgênios/farmacologia , Fungicidas Industriais/efeitos adversos , Hexaclorobenzeno/efeitos adversos , Próstata/efeitos dos fármacos , Androgênios/biossíntese , Animais , Bioensaio/métodos , Técnicas de Cultura de Células , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/farmacologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Transgênicos , Regiões Promotoras Genéticas , Próstata/enzimologia , Neoplasias da Próstata/etiologia , Ratos
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