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1.
J Public Health (Oxf) ; 37(1): 50-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24618182

RESUMO

BACKGROUND: The proportion of media sports coverage devoted to women is reported at between 1 and 6%. Our survey examines and compares reporting patterns before and after the 2012 Olympics and Paralympics. METHODS: We collected data on sports coverage in six national newspapers on 3 weekend days in February and March 2012, and in February 2013; ∼5 months before the opening of the 2012 Olympic Games and 5 months after the closing of the Paralympic Games. RESULTS: In 2012, 39 of 876 articles in national newspapers (4.5%) related to women's sports, compared with 22 of 755 (2.9%) in 2013; a non-significant reduction in coverage [difference 1.54%, 95% confidence interval (CI) -0.28 to 3.36). In 2012, 24 of 647 pictures (3.7%) related to women's activities, compared with 10 of 738 (1.4%) in 2013; a significant reduction in coverage (difference 2.35%; 95% CI 0.68-4.03). The median area per article was significantly greater for men in both years. CONCLUSIONS: We found a continuing bias towards men's sport in the media analysed and no evidence of improvement either before or after the 2012 Olympics and Paralympics. Increased support of women's sport in the print media could benefit individuals and influence the health of the population.


Assuntos
Jornais como Assunto/estatística & dados numéricos , Sexismo/estatística & dados numéricos , Esportes/estatística & dados numéricos , Feminino , Humanos , Londres , Masculino
2.
Mol Microbiol ; 36(1): 211-22, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10760178

RESUMO

MelR is a melibiose-triggered transcription activator that belongs to the AraC family of transcription factors. Using purified Escherichia coli RNA polymerase and a cloned DNA fragment carrying the entire melibiose operon intergenic region, we have demonstrated in vitro open complex formation and activation of transcription initiation at the melAB promoter. This activation is dependent on MelR and melibiose. These studies also show that the cyclic AMP receptor protein (CRP) interacts with the melAB promoter and increases MelR-dependent transcription activation. DNAase I footprinting has been exploited to investigate the location of MelR-and CRP-binding sites at the melAB promoter. We showed previously that MelR binds to two identical 18 bp target sequences centred at position -100.5 (Site 1) and position -62.5 (Site 2). In this work, we show that MelR additionally binds to two other related 18 bp sequences: Site 1', centred at position -120.5, located immediately upstream of Site 1, and Site R, at position -238.5, which overlaps the transcription start site of the divergent melR promoter. MelR can bind to Site 1', Site 1, Site 2 and Site R, in both the absence and the presence of melibiose. However, in the presence of melibiose, MelR also binds to a fifth site (Site 2', centred at position -42.5) located immediately downstream of Site 2, and overlapping the -35 region of the melAB promoter. Additionally, although CRP is unable to bind to the melAB promoter in the absence of MelR, in the presence of MelR, it binds to a site located between MelR binding Site 1 and Site 2. Thus, tandem-bound MelR recruits CRP to the MelR. We propose that expression from the melAB promoter has an absolute requirement for MelR binding to Site 2'. Optimal expression of the melAB promoter requires Sites 1', Site 1, Site 2 and Site 2'; CRP acts as a 'bridge' between MelR bound at Sites 1' and 1 and at Sites 2 and 2', increasing expression from the melAB promoter. In support of this model, we show that improvement of the base sequence of Site 2' removes the requirement for Site 1' and Site 1, and short circuits the effects of CRP.


Assuntos
Proteína Receptora de AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Escherichia coli , Escherichia coli/genética , Proteínas de Membrana Transportadoras/genética , Regiões Promotoras Genéticas , Simportadores , Transativadores/metabolismo , Sequência de Bases , Sítios de Ligação , Pegada de DNA , RNA Polimerases Dirigidas por DNA/metabolismo , Desoxirribonuclease I/metabolismo , Melibiose/metabolismo , Modelos Genéticos , Dados de Sequência Molecular , Óperon , Ligação Proteica , Ativação Transcricional
3.
J Mol Biol ; 277(4): 789-804, 1998 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-9545373

RESUMO

We have constructed a family of promoters carrying tandem DNA sites for the Escherichia coli cyclic AMP receptor protein (CRP), with one of the sites centred between base-pairs 41 and 42 upstream from the transcription start site, and the second site located further upstream. In vivo activity measurements show that the activity of these promoters is completely dependent on CRP and that, depending on the precise location, CRP bound at the upstream site increases transcription activation. Hydroxyl radical footprinting was exploited to investigate the binding of CRP and RNA polymerase holoenzyme (RNAP) to these promoters. The study shows that the C-terminal domains of the RNAP alpha subunits bind adjacent to the upstream CRP and that their precise positioning depends on the location of upstream-bound CRP. The C-terminal domains of the RNAP alpha subunits interact with both the upstream and downstream-bound CRP via activating region 1 of CRP.


Assuntos
Proteína Receptora de AMP Cíclico/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Regiões Promotoras Genéticas , Sequência de Bases , Sítios de Ligação/genética , Pegada de DNA , Primers do DNA/genética , DNA Bacteriano/química , RNA Polimerases Dirigidas por DNA/química , Escherichia coli/enzimologia , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Conformação de Ácido Nucleico , Conformação Proteica , Ativação Transcricional
4.
Nucleic Acids Res ; 25(2): 326-32, 1997 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9016561

RESUMO

Transcription activation by the Escherichia coli cyclic AMP receptor protein (CRP) at Class II promoters is dependent on direct interactions between two surface-exposed activating regions (AR1 and AR2) and two contact sites in RNA polymerase. The effects on transcription activation of disrupting either AR1 or AR2 have been measured at different Class II promoters. AR2 but not AR1 is essential for activation at all the Class II promoters that were tested. The effects of single positive control substitutions in AR1 and AR2 vary from one promoter to another: the effects of the different substitutions are contingent on the -35 hexamer sequence. Abortive initiation assays have been used to quantify the effects of positive control substitutions in each activating region on the kinetics of transcription initiation at the Class II CRP- dependent promoter pmelRcon. At this promoter, the HL159 substitution in AR1 results in a defect in the initial binding of RNA polymerase whilst the KE101 substitution in AR2 reduces the rate of isomerization from the closed to the open complex.


Assuntos
Proteína Receptora de AMP Cíclico/metabolismo , Escherichia coli/química , Regiões Promotoras Genéticas/genética , Ativação Transcricional/genética , Sequência de Bases , Sítios de Ligação/genética , Proteínas de Transporte , Clonagem Molecular , Proteína Receptora de AMP Cíclico/farmacologia , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/metabolismo , Cinética , Dados de Sequência Molecular , Ligação Proteica , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
5.
Am J Physiol ; 263(1 Pt 2): F116-26, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1636736

RESUMO

Patch clamp technology was utilized to study the effects of apical phospholipase A2 (PLA2) metabolites on "maxi K" channels in the principal cell apical membrane of rabbit cortical collecting tubule (CCT) primary cultures (B. N. Ling, C. F. Hinton, and D. C. Eaton. Kidney Int. 40: 441-452, 1991). At resting membrane potential, this channel is quiescent in the cell-attached configuration. Apical application of the PLA2 agonist melittin (1 microgram/ml) for 10 min increased single-channel open probability (Po) from 0.0004 +/- 0.0010 to 0.11 +/- 0.05. Similarly, apical exposure to 50 microM arachidonic acid (AA) or 0.5 microM prostaglandin (PG) E2, but not 0.5 microM PGF2 alpha, also increased channel activity. Conversely, 10 microM of the PLA2 antagonist quinacrine applied apically decreased Po. Removal of apical bath Ca2+ did not prevent melittin-, AA-, or PGE2-induced channel activation. We then examined the role of maxi K channels and eicosanoids in principal cell volume regulation. Within seconds of reducing basolateral bath tonicity (285 to 214 mosmol/kgH2O), NPo (i.e., no. of channels x Po) initially increased approximately 200%, followed by a delayed but prolonged activation phase that was attenuated by removal of apical bath Ca2+. Pretreatment with 10 microM quinacrine, 100 microM indomethacin (cyclooxygenase inhibitor), or 0.25 microM thapsigargin (to deplete intracellular Ca2+ stores) abolished the initial phase of swelling-induced channel activation.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cálcio/fisiologia , Eicosanoides/fisiologia , Túbulos Renais Coletores/metabolismo , Canais de Potássio/metabolismo , Animais , Cálcio/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Espaço Extracelular/metabolismo , Soluções Hipotônicas/farmacologia , Túbulos Renais Coletores/citologia , Túbulos Renais Coletores/efeitos dos fármacos , Cinética , Fosfolipases A/metabolismo , Fosfolipases A/fisiologia , Fosfolipases A2 , Coelhos , Cloreto de Sódio/farmacologia
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