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1.
Int J Audiol ; 55 Suppl 3: S23-33, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26919044

RESUMO

OBJECTIVE: To assess (1) the feasibility of incorporating the Ida Institute's Motivation Tools into a UK audiology service, (2) the potential benefits of motivational engagement in first-time hearing aid users, and (3) predictors of hearing aid and general health outcome measures. DESIGN: A feasibility study using a single-centre, prospective, quasi-randomized controlled design with two arms. The Ida Institute's Motivation Tools formed the basis for motivational engagement. STUDY SAMPLE: First-time hearing aid users were recruited at the initial hearing assessment appointment. The intervention arm underwent motivational engagement (M+, n = 32), and a control arm (M-, n = 36) received standard care only. RESULTS: The M+ group showed greater self-efficacy, reduced anxiety, and greater engagement with the audiologist at assessment and fitting appointments. However, there were no significant between-group differences 10-weeks post-fitting. Hearing-related communication scores predicted anxiety, and social isolation scores predicted depression for the M+ group. Readiness to address hearing difficulties predicted hearing aid outcomes for the M- group. Hearing sensitivity was not a predictor of outcomes. CONCLUSIONS: There were some positive results from motivational engagement early in the patient journey. Future research should consider using qualitative methods to explore whether there are longer-term benefits of motivational engagement in hearing aid users.


Assuntos
Correção de Deficiência Auditiva/instrumentação , Correção de Deficiência Auditiva/psicologia , Auxiliares de Audição , Transtornos da Audição/psicologia , Transtornos da Audição/terapia , Motivação , Entrevista Motivacional , Aceitação pelo Paciente de Cuidados de Saúde , Pessoas com Deficiência Auditiva/psicologia , Pessoas com Deficiência Auditiva/reabilitação , Idoso , Idoso de 80 Anos ou mais , Agendamento de Consultas , Percepção Auditiva , Inglaterra , Estudos de Viabilidade , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Autoeficácia , Isolamento Social , Resultado do Tratamento
2.
Ear Hear ; 36(4): 417-29, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25587668

RESUMO

OBJECTIVES: In many countries including the United Kingdom, hearing aids are a first line of audiologic intervention for many people with tinnitus and aidable hearing loss. Nevertheless, there is a lack of high quality evidence to support that they are of benefit for tinnitus, and wide variability in their use in clinical practice especially for people with mild hearing loss. The aim of this study was to identify a consensus among a sample of UK clinicians on the criteria for hearing aid candidature and clinical practice in fitting hearing aids specifically for mild hearing loss with and without tinnitus. This will allow professionals to establish clinical benchmarks and to gauge their practice with that used elsewhere. DESIGN: The Delphi technique, a systematic methodology that seeks consensus amongst experts through consultation using a series of iterative questionnaires, was used. A three-round Delphi survey explored clinical consensus among a panel of 29 UK hearing professionals. The authors measured panel agreement on 115 statements covering: (i) general factors affecting the decision to fit hearing aids, (ii) protocol-driven factors affecting the decision to fit hearing aids, (iii) general practice, and (iv) clinical observations. Consensus was defined as a priori ≥70% agreement across the panel. RESULTS: Consensus was reached for 58 of the 115 statements. The broad areas of consensus were around factors important to consider when fitting hearing aids; hearing aid technology/features offered; and important clinical assessment to verify hearing aid fit (agreement of 70% or more). For patients with mild hearing loss, the greatest priority was given by clinicians to patient-centered criteria for fitting hearing aids: hearing difficulties, motivation to wear hearing aids, and impact of hearing loss on quality of life (chosen as top five by at least 64% of panelists). Objective measures were given a lower priority: degree of hearing loss and shape of the audiogram (chosen as top five by less than half of panelists). Areas where consensus was not reached were related to the use of questionnaires to predict and verify hearing aid benefit for both hearing and tinnitus; audiometric criteria for fitting hearing aids; and safety of using loud sounds when verifying hearing aid fitting when the patient has tinnitus (agreement of <70%). CONCLUSIONS: The authors identified practices that are considered important when recommending or fitting hearing aid for a patient with tinnitus. More importantly perhaps, they identified practical issues where there are divided opinions. Their findings inform the design of clinical trials and open up debate on the potential impact of practice differences on patient outcomes.


Assuntos
Correção de Deficiência Auditiva/métodos , Auxiliares de Audição , Perda Auditiva/reabilitação , Zumbido/reabilitação , Técnica Delphi , Perda Auditiva/complicações , Humanos , Ajuste de Prótese , Índice de Gravidade de Doença , Zumbido/complicações , Reino Unido
3.
Reprod Biol Endocrinol ; 11: 30, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23587111

RESUMO

BACKGROUND: Placental production of corticotrophin releasing hormone (CRH) rises exponentially as pregnancy progresses, and has been linked with the onset of normal and preterm labour. CRH is produced in syncytiotrophoblast cells and production is increased by glucocorticoids and cAMP. It remains unclear whether cAMP acts by inducing differentiation of cytotrophoblasts and/or through induction of syncytialisation. As CRH can stimulate cAMP pathways we have tested whether a feed-forward system may exist in placental cells during syncytialisation. METHODS: The choriocarcinoma BeWo cell line was treated with cAMP, CRH or vehicle. Cell viability was determined by MTT assay, while apoptosis was analysed by DAPI staining and by FACS. Differentiation was measured by assaying message for hCG and ERVW-1 (syncytin1) by qRT-PCR, as well as the respective protein by ELISA. Fusion of BeWo cells was assessed by co-staining cell membrane and nuclei with CellMask and Hoechst 33342. CRHR1 and CRHR2 mRNA levels were measured by qRT-PCR. RESULTS: We show that cAMP has an inductive effect on syncytialisation, as evidenced by induction of hCG secretion, by ERVW-1 mRNA expression and by formation of multinuclear cells. CRH mRNA expression was found to increase prior to the changes in the other syncytialisation markers. cAMP had an inhibitory effect on BeWo cell viability, but exogenous CRH did not. However, CRH did mimic the differentiation inducing effect of cAMP, suggesting a link between CRH and cAMP signalling in syncytialisation. We also found that treatment of BeWo cells with exogenous CRH resulted in elevated cellular CRHR1 levels. CONCLUSIONS: This study suggests a positive feed-forward role exists for CRH in trophoblast cell differentiation, which may underlie the exponential rise in CRH observed as gestation advances.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Hormônio Liberador da Corticotropina/farmacologia , AMP Cíclico/farmacologia , Trofoblastos/efeitos dos fármacos , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Diferenciação Celular/genética , Fusão Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Coriocarcinoma/genética , Coriocarcinoma/metabolismo , Coriocarcinoma/patologia , Gonadotropina Coriônica/genética , Gonadotropina Coriônica/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Expressão Gênica/efeitos dos fármacos , Produtos do Gene env/genética , Produtos do Gene env/metabolismo , Células Gigantes/efeitos dos fármacos , Células Gigantes/metabolismo , Humanos , Gravidez , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Receptores de Hormônio Liberador da Corticotropina/genética , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Trofoblastos/metabolismo , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patologia
4.
Pilot Feasibility Stud ; 8(1): 235, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329548

RESUMO

BACKGROUND: Education and advice is provided for tinnitus management in all UK audiology clinics. Sound therapy, including provision of hearing aids may be offered, but this is often dependent on a clinician's decision rather than UK policy. This inconsistent management reflects a lack of evidence around the effectiveness of hearing aids for tinnitus. This open-label, two-arm multicentre randomised controlled feasibility trial gathered data around recruitment, acceptability and outcome assessments to determine the feasibility of conducting a large randomised controlled trial investigating the effectiveness of hearing aids for tinnitus management. METHODS: Adults referred to audiology for tinnitus, with an aidable hearing loss were recruited at five UK audiology clinics. They were randomised 1:1 to either education and advice (treatment as usual (TAU), n = 41) or TAU plus hearing aids (n = 42). Outcomes were collected by questionnaires 12 weeks after randomisation. After participation, interviews were conducted with a subset of both participants and clinicians from each trial centre. RESULTS: Eighty three participants from five sites were randomised. Non-aidable hearing loss was the main reason for ineligibility to participate in the trial reported by the sites. Seventy three percent of participants returned the 12-week questionnaires, with return rates by site ranging from 61 to 100%. Fifteen out of 33 participants (45%) reported using hearing aids for the clinician-recommended time, or longer, during the day. The Tinnitus Functional Index (TFI) was the outcome measure most responsive to change. The majority of participants also agreed it was relevant to their tinnitus and hearing loss. Qualitative data demonstrated that the trial was acceptable to participants. Feedback from clinicians revealed a potential lack of equipoise. It also highlighted the differences in referral and treatment pathways between departments and differences in audiometric criteria for fitting hearing aids. Health economic measures were well completed for those returned. No change in health-related quality of life was observed. Costs were higher in the intervention arm, but self-reports of healthcare service use indicated participant confusion in treatment pathways. CONCLUSIONS: This feasibility trial is the first step towards obtaining high quality evidence to determine potential clinical effectiveness and cost effectiveness of hearing aids for tinnitus versus usual care. A definitive trial was deemed to be feasible, with some modifications based on feasibility findings and using the TFI as the primary outcome. This trial was funded by the National Institute for Health Research, Research for Patient Benefit Programme (PB-PG-0816-20,014) and registered with ISRCTN (ISRCTN14218416).

5.
Artigo em Inglês | MEDLINE | ID: mdl-32231789

RESUMO

BACKGROUND: The most common management strategy for tinnitus provided in the UK audiology clinics is education and advice. This may also be combined with some form of sound therapy (e.g. digital hearing aids). While education and advice is generally provided by all clinics, there is a marked variability in provision of hearing aids that depends very much on clinical decisions. A recent Cochrane review concluded a lack of evidence to support or refute hearing aid use as a routine intervention for people with tinnitus and hearing loss. This lack of evidence is reflected in the inconsistency of tinnitus management in the UK. The aim of the HUSH trial is to determine the feasibility of conducting a definitive randomised controlled trial (RCT) of the effectiveness and cost-effectiveness of hearing aids for adults with tinnitus and hearing loss. METHODS: This is a multicentre randomised controlled feasibility trial. Up to 100 adults, aged 18 and over, presenting to 5 UK audiology clinics with a complaint of tinnitus and measurable hearing loss are being randomised to receive either (i) education and advice (treatment as usual) or (ii) education and advice with digital hearing aids. Feasibility outcomes are being collected around recruitment, retention, patient and healthcare professional acceptability and clinical outcome assessment. Outcomes are being collected via postal questionnaire at 12 weeks post baseline. A nested interview study will supplement clinical and other outcome data, providing a detailed understanding of participants' and audiologists' experience of both tinnitus management and the research processes. DISCUSSION: This feasibility trial will help us to (i) determine if it is feasible to conduct a multicentre RCT comparing treatment as usual and treatment as usual plus digital hearing aids; (ii) optimise the design of a future definitive, multicentre RCT; and (iii) inform which outcome(s) is/are relevant for patients. This work presents an important first step in determining the effectiveness of hearing aids as a tinnitus management strategy. TRIAL REGISTRATION: ISRCTN, ISRCTN14218416. Registered on 30 July 2018.

6.
Reprod Biol Endocrinol ; 7: 74, 2009 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-19615077

RESUMO

BACKGROUND: Classically protein kinase A (PKA) and transcription factor activator protein 1 (AP-1) mediate the cyclic AMP (cAMP) induced-corticotrophin releasing hormone (CRH) expression in the placenta. However enteric Gram (-) bacterial cell wall component lipopolysaccharide (LPS) may also induce-CRH expression via Toll like receptor (TLR)4 and its adaptor molecule Myd88. Here we investigated the role of MyD88, TRIF and IRAK2 on cAMP-induced CRH promoter activation in JEG3 cells in the absence of LPS/TLR4 stimulation. METHODS: JEG3 cells were transfected with CRH-luciferase and Beta-galactosidase expression vectors and either empty or dominant-negative (DN)-MyD88, DN-TRIF or DN-IRAK2 vectors using Fugene6 (Roche). cAMP-induced CRH promoter activation was examined by using a luminometer and luciferase assay. Calorimetric Beta-galactosidase assays were performed to correct for transfection efficiency. Luciferase expression vectors of cAMP-downstream molecules, CRE and AP-1, were used to further examine the signaling cascades. RESULTS: cAMP stimulation induced AP-1 and CRE promoter expression and led to dose-dependent CRH promoter activation in JEG3 cells. Inhibition of MyD88 signaling blocked cAMP-induced CRE and CRH promoter activation. Inhibition of TRIF signaling blocked cAMP-induced CRH but not CRE expression, while inhibition of IRAK2 did not have an effect on cAMP-induced CRH expression. CONCLUSION: MyD88 and TRIF exert direct regulatory effect on cAMP-induced CRH promoter activation in JEG3 cells in the absence of infection. MyD88 most likely interacts with molecules upstream of IRAK2 to regulate cAMP-induced CRH expression.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/fisiologia , Hormônio Liberador da Corticotropina/biossíntese , AMP Cíclico/fisiologia , Fator 88 de Diferenciação Mieloide/fisiologia , Linhagem Celular Tumoral , Hormônio Liberador da Corticotropina/metabolismo , Expressão Gênica , Humanos , Quinases Associadas a Receptores de Interleucina-1/fisiologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/fisiologia , Transfecção
7.
Am J Obstet Gynecol ; 199(3): 317.e1-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18771998

RESUMO

OBJECTIVE: We hypothesized that intrauterine infection may lead to placental corticotrophin-releasing hormone (CRH) expression via Toll-like receptor signaling. STUDY DESIGN: To test this hypothesis JEG3 cells were stimulated with lipopolysaccharide (LPS), chlamydial heat shock protein 60, and interleukin (IL)-1. CRH expression was assessed by reverse transcription polymerase chain reaction (RT-PCR). The signaling mechanisms that were involved were examined in transient transfection experiments with beta-galactosidase, CRH-luciferase, cyclic adenosine monophosphate (AMP) response element-luciferase, dominant-negative (DN)-myeloid differentiation primary response gene (MyD88) and DN-toll-IL-1-receptor domain containing adapter inducing interferon (TRIF) vectors. Luciferase activity was determined by luciferase assay. Beta-galactosidase assay was performed to determine transfection efficiency. RESULTS: LPS, chlamydial heat shock protein 60, and IL-1 stimulation led to CRH expression in the JEG3 cells. LPS-induced CRH expression was not due to the autocrine effect of LPS-induced IL-1 because the supernatant from LPS-conditioned JEG3 cells did not induce CRH expression in the naïve cells. DN-MyD88, but not DN-TRIF, blocked the LPS-induced CRH expression. The cAMP response element did not play a role in LPS-induced CRH expression. CONCLUSION: Toll-like receptor signaling 4 may induce placental CRH expression through MyD88.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Lipopolissacarídeos/farmacologia , Fator 88 de Diferenciação Mieloide/fisiologia , Receptor 4 Toll-Like/fisiologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/fisiologia , Proteínas Adaptadoras de Transporte Vesicular , Antígenos de Bactérias , Células Cultivadas , Chaperonina 60/farmacologia , Feminino , Humanos , Interleucina-1beta/farmacologia , Luciferases , Trabalho de Parto Prematuro/fisiopatologia , Placenta/fisiologia , Gravidez , Receptores Imunológicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
8.
Front Biosci ; 12: 581-90, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17127319

RESUMO

Glucocorticoids inhibit corticotrophin-releasing hormone (CRH) gene expression in the hypothalamic paraventricular nucleus (PVN), but stimulate expression in the placenta. In AtT20 cells (a model of PVN CRH production) cAMP produces a high level of promoter activity. Cyclic AMP stimulation occurs through the cAMP response element (CRE) and the caudal type homeobox protein response element (CDXARE). The CRE acts as part of a cAMP response unit that includes the hybrid steroid response element (HRE), ecdysone response element (EcRE), metal-responsive transcription factor-1 response element (MTFRE), ying yang 1 response element (YY1RE) and negative glucocorticoid response element (nGRE). Cyclic AMP acts on the HRE, EcRE and MTFRE to block YY1RE mediated inhibition of the CRE. Glucocorticoids acting at the nGRE inhibit cAMP activation of the CRE. In placental cells the CRH promoter has low intrinsic basal activity and cAMP causes a modest increase in activity. Stimulation by glucocorticoids and cAMP and inhibition by estrogen and estrogen receptor alpha occurs through the CRE. In AtT20 cells multiple response elements coordinate a response to cAMP and glucocorticoids while in placental cells the CRE acts in isolation. These differences in promoter function lead to responses that meet specific physiological needs.


Assuntos
Hormônio Liberador da Corticotropina/genética , Regulação da Expressão Gênica , Elementos de Resposta , Animais , Hormônio Liberador da Corticotropina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Humanos , Placenta/metabolismo , Regiões Promotoras Genéticas
9.
Front Biosci ; 12: 912-8, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17127348

RESUMO

Corticotrophin-releasing hormone (CRH) is the hypothalamic peptide that controls the function of the pituitary-adrenal axis in response to stress. CRH is also expressed abundantly in the human placenta and is present in high concentrations in maternal and fetal plasma during late pregnancy. During pregnancy, CRH derived from the placenta is thought to play a crucial role in the regulation of fetal maturation and the timing of delivery, and CRH has also been implicated in the control of fetal-placental blood flow. Elevated CRH concentrations, as compared with gestational age matched controls, occur in patients in preterm labour. The exponential curve depicting the CRH increase is shifted to the left in women who will subsequently deliver preterm and to the right in women who will deliver post dates. This has led to the suggestion that CRH production is linked to a placental clock which determines the length of gestation. Clinically, maternal plasma CRH concentrations may be useful in identifying women at high risk of preterm delivery and CRH antagonists may be useful in preventing preterm labour. As significant CRH production by the placenta is restricted to primates, future research must take into account the species specificity of the mechanisms regulating parturition. A number of significant gaps remain in our knowledge of the function of this peptide in pregnancy. This review examines the current evidence regarding the role of CRH in human parturition.


Assuntos
Hormônio Liberador da Corticotropina/fisiologia , Parto/fisiologia , Glândulas Suprarrenais/embriologia , Animais , Relógios Biológicos , Hormônio Liberador da Corticotropina/biossíntese , Hormônio Liberador da Corticotropina/sangue , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Modelos Animais , Miométrio/metabolismo , Sistema Hipófise-Suprarrenal/fisiologia , Placenta/irrigação sanguínea , Placenta/química , Placenta/metabolismo , Gravidez
10.
Front Biosci ; 11: 2909-17, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16720362

RESUMO

Corticotropin-releasing hormone (CRH), a 41 amino acid polypeptide, is expressed in many regions of central nervous system and peripheral tissues and mediates many physiological functions. Abnormal production of CRH is involved in some pathological processes. Among various endogenous factors that modulate CRH production, steroid hormones control CRH production by regulating its gene transcription. Although there is no classical steroid hormone response element in the CRH promoter, steroid hormones regulate CRH gene expression through protein-protein interaction or by binding directly to response elements.


Assuntos
Androgênios/fisiologia , Hormônio Liberador da Corticotropina/biossíntese , Hormônio Liberador da Corticotropina/genética , Estrogênios/fisiologia , Progesterona/fisiologia , Regulação para Baixo , Regulação da Expressão Gênica , Glucocorticoides/fisiologia , Humanos , Regiões Promotoras Genéticas/genética , Ligação Proteica , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/biossíntese
11.
Int J Endocrinol ; 2015: 861302, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26457081

RESUMO

Corticotropin releasing hormone (CRH) production by the human placenta increases exponentially as pregnancy advances, and the rate of increase predicts gestational length. CRH gene expression is regulated by cAMP in trophoblasts through a cyclic AMP-response element (CRE), which changes its transcription factor binding properties upon methylation. Here we determined whether methylation of the CRH proximal promoter controls basal and cAMP-stimulated CRH expression in BeWo cells, a well-characterized trophoblastic cell line. We treated the cells with 8-Br-cAMP and the DNA methyltransferase inhibitor 5-aza-2' deoxycytidine (5-AZA-dC) and determined the effects on CRH mRNA level and promoter methylation. Clonal bisulfite sequencing showed partial and allele independent methylation of CpGs in the CRH promoter. CRH mRNA expression and the methylation of a subset of CpGs (including CpG2 in the CRE) increased spontaneously during culture. 8-Br-cAMP stimulated CRH expression without affecting the increase in methylation. 5-AZA-dC decreased methylation and augmented 8-Br-cAMP-stimulated CRH expression, but it blocked the spontaneous increase of CRH mRNA level. We conclude that the CRH promoter is a dynamically and intermediately methylated genomic region in BeWo cells. Promoter methylation did not inhibit CRH gene expression under the conditions employed; rather it determined the contribution of alternative cAMP-independent pathways and cAMP-independent mechanisms to CRH expression control.

12.
J Clin Endocrinol Metab ; 87(8): 3774-8, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12161509

RESUMO

CRH and estrogens, produced by placental trophoblasts, have been suggested to play pivotal roles in the control of human parturition. Estrogen has been shown to affect hypothalamic CRH expression. Therefore, we evaluated 17 beta-estradiol (E2) in the regulation of CRH gene expression in placental cells. E2 inhibited CRH mRNA expression in a dose-dependent manner, which paralleled the decrease in CRH protein levels in culture media. A complete estrogen receptor (ER) antagonist, ICI 182780, not only blocked repression of CRH mRNA levels by E2, but up-regulated CRH mRNA and protein synthesis. An ER alpha-mixed agonist/antagonist and ER beta antagonist, 4-hydroxytamoxifen, also down-regulated CRH gene expression. Using quantitative RT-PCR, we found that placental trophoblasts express predominantly the ER alpha form of the receptor. Transient transfection assays conducted in the choriocarcinoma cell line JEG-3 demonstrated that E2 repressed CRH promoter activity, whereas the antagonist ICI 182780 up-regulated CRH promoter activity when ER alpha was cotransfected. These studies demonstrate that E2 represses placental CRH gene expression through an ER alpha-mediated mechanism. Estrogen may therefore modulate placental CRH production, influencing the rate of rise of maternal plasma CRH concentrations and potentially the length of gestation.


Assuntos
Hormônio Liberador da Corticotropina/genética , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Estrogênios/farmacologia , Placenta/efeitos dos fármacos , Células Cultivadas , Hormônio Liberador da Corticotropina/análise , Estradiol/análogos & derivados , Receptor alfa de Estrogênio , Feminino , Fulvestranto , Expressão Gênica/efeitos dos fármacos , Humanos , Placenta/química , Placenta/citologia , Gravidez , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/análise , Receptores de Estrogênio/metabolismo
13.
J Clin Endocrinol Metab ; 89(5): 2312-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15126558

RESUMO

Placental CRH plays a major role in the mechanisms controlling human pregnancy and parturition. Understanding how placental CRH production is regulated is therefore of importance. Previously we have shown that placental expression of CRH peptide and mRNA are inhibited by estrogens, in contrast to the stimulatory effects of estrogen on hypothalamic CRH production. Our current study found that in placental cells cotransfected with a CRH promoter construct and an estrogen receptor-alpha expression vector results in a differential regulation whereby 17beta-estradiol (E2) decreased and the putative pure estrogen antagonist, ICI 182780, increased CRH promoter activity. Sequential deletion of the CRH promoter indicated that the region between -248 and -213 bp was essential for the effect of both E2 and ICI 182780. This region contains a consensus cAMP regulatory element (CRE) that is a requirement for E2- and ICI 182780-mediated activity because the CRE motif can confer E2 inhibition on a heterologous promoter such as rabbit beta-globin. Mutation of the CRE resulted in a complete reversal of E2 and ICI 182780 regulatory effects. In summary, our results demonstrate that a consensus CRE is required for the action of estrogen receptor ligands in human placental syncytiotrophoblast cells.


Assuntos
Hormônio Liberador da Corticotropina/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Regulação da Expressão Gênica , Placenta/metabolismo , Receptores de Estrogênio/fisiologia , Trofoblastos/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Células Cultivadas/metabolismo , Regulação para Baixo/fisiologia , Estradiol/farmacologia , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Estrogênios/fisiologia , Feminino , Humanos , Ligantes , Placenta/citologia , Gravidez , Regiões Promotoras Genéticas/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Elementos de Resposta/genética
15.
Front Biosci ; 9: 32-9, 2004 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-14766341

RESUMO

Glucocorticoids inhibit corticotrophin releasing hormone (CRH) production in the hypothalamus but stimulate production from the placenta. To identify key elements regulating the CRH gene, mouse pituitary tumor-derived cells (AtT20 cells) were used as a hypothalamic model in an analysis of the CRH promoter. Two cAMP responsive elements were identified: (I) a consensus cAMP response element (CRE) and (II) a previously unrecognized caudal-type homeobox response element (CDXRE). Glucocorticoids inhibit only the component of cAMP-stimulation occurring via the CRE through an action involving a negative glucocorticoid response element (nGRE). We also identified two regions that, in the absence of the nGRE, can be stimulated by glucocorticoids: (I) the CRE and (II) a region between -213 to -99bps. Electrophoretic mobility shift assays identified binding of the transcription factors CREB and Fos at the CRE in AtT20 cells, whereas CREB and cJun were detected in placental cells. In addition, a novel CRE-binding transcription factor has been identified that is expressed in the brain and in placenta. A model is presented whereby CRH gene regulation is mediated via tissue specific expression of transcription factors.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Regulação da Expressão Gênica/fisiologia , Elementos de Resposta/fisiologia , Animais , Encéfalo/metabolismo , Hormônio Liberador da Corticotropina/genética , Camundongos , Placenta/metabolismo , Células Tumorais Cultivadas
16.
Mol Cell Endocrinol ; 194(1-2): 19-28, 2002 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-12242024

RESUMO

Glucocorticoids inhibit corticotrophin releasing hormone (CRH) production in the hypothalamus but stimulate production from the placenta. We have sought to identify the key elements regulating the CRH gene. Mouse pituitary tumour-derived cells (AtT20 cells) were used in deletion and mutational analyses of the CRH promoter. Two cAMP responsive elements were identified: (I) a consensus cAMP response element (CRE) and (II) a previously unrecognised caudal-type homeobox response element (CDXRE). Glucocorticoids inhibit only the component of cAMP-stimulation occurring via the CRE through an action involving a negative glucocorticoid response element (nGRE). We also identified two regions that, in the absence of the nGRE, can be stimulated by glucocorticoids: (I) the CRE and (II) a region between -213 and -99 bps. Electrophoretic mobility shift assays (EMSAs) identified binding of the transcription factors CREB and Fos at the CRE in AtT20 cells while CREB and cJun were detected in placental cells. Tissue specific expression of transcription factors may mediate regulation of the CRH gene.


Assuntos
Hormônio Liberador da Corticotropina/genética , AMP Cíclico/farmacologia , Glucocorticoides/farmacologia , Regiões Promotoras Genéticas/genética , Animais , Hormônio Liberador da Corticotropina/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Mutagênese Sítio-Dirigida , Hipófise/citologia , Placenta/citologia , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Elementos de Resposta , Transfecção , Células Tumorais Cultivadas
17.
Hastings Cent Rep ; 17(3): S23-6, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11644026

RESUMO

KIE: A 65-year-old competent nursing home patient, suffering from amyotrophic lateral sclerosis and respirator dependent, refuses a nasogastric feeding tube even though she realizes that her refusal will result in death. The nursing staff and the patient's husband support her decision but two of her three children want her life prolonged. Nicholson, Qiu, and Koch and Ulshoefer discuss whether the refusal would be honored in Britain, China, and West Germany respectively. In Britain, this patient would receive palliative care, and both the respirator and the nasogastric tube would be considered extraordinary and not offered. In China, medical technologies are scarce, physicians are divided on treatment refusal, and the family's attitudes would be influenced by the Confucian tradition of filial piety and whether or not the patient was eligible for free care. In West Germany, this case would be legally considered "passive euthanasia" and the patient's refusal would be honored.^ieng


Assuntos
Esclerose Lateral Amiotrófica , Nutrição Enteral , Eutanásia Passiva , Liberdade , Cooperação Internacional , Internacionalidade , Apoio Nutricional , Autonomia Pessoal , Direito a Morrer , Recusa do Paciente ao Tratamento , Atitude , Doenças do Sistema Nervoso Central , China , Tomada de Decisões , Equipamentos e Provisões , Eutanásia , Eutanásia Ativa , Eutanásia Ativa Voluntária , Família , Alocação de Recursos para a Atenção à Saúde , Humanos , Jurisprudência , Cuidados para Prolongar a Vida , Obrigações Morais , Cuidados Paliativos , Pacientes , Preparações Farmacêuticas , Médicos , Alocação de Recursos , Responsabilidade Social , Estresse Psicológico , Suicídio , Assistência Terminal , Doente Terminal , Reino Unido , Estados Unidos , Suspensão de Tratamento
18.
Health Serv J ; 112(5808): 26-7, 2002 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-12087716

RESUMO

Involving clinicians, lay members and managers on the boards of primary care trusts has great potential for producing innovative services. The involvement of clinicians means decisions are more likely to be acceptable to staff on the frontline. It is important that strategic health authorities foster innovation and do not seek to become controlling of PCTs. It is vital that a culture of performance management does not hamper PCTs' development.


Assuntos
Participação da Comunidade , Atenção Primária à Saúde/organização & administração , Medicina Estatal/organização & administração , Conselho Diretor/organização & administração , Humanos , Cultura Organizacional , Inovação Organizacional , Médicos , Reino Unido
19.
Front Biosci (Landmark Ed) ; 17(2): 713-25, 2012 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-22201770

RESUMO

Corticotropin Releasing Hormone (CRH), a 41-amino acid peptide, is a major regulator of hypothalamic-pituitary-adrenal axis function. CRH also has important roles in several processes pertaining to pregnancy and parturition, including being a possible regulator of gestational length and predictor of pre-term birth. Regulation of the CRH promoter exhibits some tissue-specificities, the most well characterized example being glucocorticoids, which can stimulate placental CRH production but suppress hypothalamic CRH. In the last decade there has been growing interest in the role of epigenetic regulation of gene expression. Modification of the structure of chromatin is an example of epigenetic change affecting gene expression. We have found that inhibition of histone deacetylases results in an increase in CRH expression in the AtT20 pituitary cell line, but a decrease in CRH expression in the placenta. In this paper we review tissue specific differences in CRH gene expression, and discuss how epigenetic chromatin modification mechanisms can relate to tissue specific differences in expression of CRH.


Assuntos
Hormônio Liberador da Corticotropina/genética , Epigênese Genética , Feminino , Regulação da Expressão Gênica , Histona Desacetilases/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Modelos Biológicos , Sistema Hipófise-Suprarrenal/metabolismo , Placenta/metabolismo , Gravidez , Regiões Promotoras Genéticas , Distribuição Tecidual
20.
Food Chem Toxicol ; 50(10): 3388-96, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22819934

RESUMO

The purpose of this study is to investigate the potential subchronic toxicity of 20(S)-Ginsenoside Rg3(Rg3), by a 26-week repeated intramuscular administration in rats. Rg3 was administrated to rats at dose levels of 0, 4.2, 10.0 or 20.0 mg/kg/day. There was no treatment-related mortality and, at the scheduled autopsy, dose-dependent increases in the absolute and relative spleen weights, of both the 10.0 mg/kg and 20.0 mg/kg dose groups were observed. Absolute and relative kidney weights were significantly elevated in the female 10.0 mg/kg dose group and in the male 20.0 mg/kg dose group. Hematological investigations revealed a dose-dependent increase in the total white blood cell (WBC) count and in the percentage of neutrophils, but a decrease in the percentage of lymphocytes, in rats treated with doses of 10.0/20.0 mg/kg. These effects were completely reversible during the recovery period, and no other adverse effects were observed. It was concluded that the 26-week repeated intramuscular dose of Rg3 caused increases in the spleen and kidney weights, WBC counts and in the percentage of neutrophils, but a decrease in the percentage of lymphocytes, with doses of 10.0 or 20.0 mg/kg/day. The no-observed-adverse-effect level for rats was considered to be 4.2 mg/kg/day.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Ginsenosídeos/toxicidade , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Peso Corporal , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Ginsenosídeos/administração & dosagem , Ginsenosídeos/química , Injeções Intramusculares , Rim/patologia , Masculino , Estrutura Molecular , Tamanho do Órgão , Ratos , Ratos Wistar , Fatores Sexuais , Baço/efeitos dos fármacos , Baço/patologia
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