Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 78
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nucleic Acids Res ; 51(1): 99-116, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36535377

RESUMO

Numerous cancers, including prostate cancer (PCa), are addicted to transcription programs driven by specific genomic regions known as super-enhancers (SEs). The robust transcription of genes at such SEs is enabled by the formation of phase-separated condensates by transcription factors and coactivators with intrinsically disordered regions. The androgen receptor (AR), the main oncogenic driver in PCa, contains large disordered regions and is co-recruited with the transcriptional coactivator mediator complex subunit 1 (MED1) to SEs in androgen-dependent PCa cells, thereby promoting oncogenic transcriptional programs. In this work, we reveal that full-length AR forms foci with liquid-like properties in different PCa models. We demonstrate that foci formation correlates with AR transcriptional activity, as this activity can be modulated by changing cellular foci content chemically or by silencing MED1. AR ability to phase separate was also validated in vitro by using recombinant full-length AR protein. We also demonstrate that AR antagonists, which suppress transcriptional activity by targeting key regions for homotypic or heterotypic interactions of this receptor, hinder foci formation in PCa cells and phase separation in vitro. Our results suggest that enhanced compartmentalization of AR and coactivators may play an important role in the activation of oncogenic transcription programs in androgen-dependent PCa.


Assuntos
Neoplasias da Próstata , Receptores Androgênicos , Masculino , Humanos , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Androgênios , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Expressão Gênica , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
2.
Aesthetic Plast Surg ; 45(1): 343-348, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32885319

RESUMO

INTRODUCTION: COVID-19, a worldwide pandemic, has enforced a national lockdown in the UK which produced a paradigm shift about the way medical practitioners would perform consultations and communication with their patients. Senior authors realised that in lockdown there was only one option to see a patient: virtual consultation via telecommunication technologies. This paper will discuss the current benefits and considerations of Telemedicine, particularly in plastic surgery, to decipher the next route of action to further validate its use for future implementation. METHOD: A detailed literature review was carried out comparing papers from 1992 to 2020. A survey of 122 consultant plastic surgeons found an encouraging result as 70% positively embraced the suggestion of Telemedicine in their current practice. DISCUSSION: Telemedicine produced equal or improved patient satisfaction. Its utilisation reduced cost for patient, clinic and consultant. With accessibility to a large percentage of the population, Telemedicine enables infection control and adherence to social distancing during COVID-19. Considerations include dependability on internet access, legal aspects, cyber security and General Data Protection Regulation (GDPR), the inability to perform palpation or physical inspection and psychological impacts on the patient. CONCLUSION: In modern times, Telemedicine has become more accessible and COVID-19 has made it more applicable than ever before. More in-depth research is needed for validation of this technique within plastic surgery. While maintaining quality of care and a vital role in social distancing, there is a strong need for standardisation of Telemedicine processes, platforms, encryption and data storage. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
COVID-19 , Telemedicina , Comunicação , Humanos , Encaminhamento e Consulta , SARS-CoV-2
3.
Proc Natl Acad Sci U S A ; 113(3): 602-7, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26733675

RESUMO

Production of a messenger RNA proceeds through sequential stages of transcription initiation and transcript elongation and termination. During each of these stages, RNA polymerase (RNAP) function is regulated by RNAP-associated protein factors. In bacteria, RNAP-associated σ factors are strictly required for promoter recognition and have historically been regarded as dedicated initiation factors. However, the primary σ factor in Escherichia coli, σ(70), can remain associated with RNAP during the transition from initiation to elongation, influencing events that occur after initiation. Quantitative studies on the extent of σ(70) retention have been limited to complexes halted during early elongation. Here, we used multiwavelength single-molecule fluorescence-colocalization microscopy to observe the σ(70)-RNAP complex during initiation from the λ PR' promoter and throughout the elongation of a long (>2,000-nt) transcript. Our results provide direct measurements of the fraction of actively transcribing complexes with bound σ(70) and the kinetics of σ(70) release from actively transcribing complexes. σ(70) release from mature elongation complexes was slow (0.0038 s(-1)); a substantial subpopulation of elongation complexes retained σ(70) throughout transcript elongation, and this fraction depended on the sequence of the initially transcribed region. We also show that elongation complexes containing σ(70) manifest enhanced recognition of a promoter-like pause element positioned hundreds of nucleotides downstream of the promoter. Together, the results provide a quantitative framework for understanding the postinitiation roles of σ(70) during transcription.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Fator sigma/metabolismo , Transcrição Gênica , Sequência de Bases , Regulação Bacteriana da Expressão Gênica , Cinética , Lasers , Dados de Sequência Molecular , Nucleotídeos/metabolismo , Fotodegradação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Moldes Genéticos , Fatores de Tempo , Elongação da Transcrição Genética
4.
J Biol Chem ; 292(29): 12165-12177, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28515322

RESUMO

Gi/o-coupled G protein-coupled receptors can inhibit neurotransmitter release at synapses via multiple mechanisms. In addition to Gßγ-mediated modulation of voltage-gated calcium channels (VGCC), inhibition can also be mediated through the direct interaction of Gßγ subunits with the soluble N-ethylmaleimide attachment protein receptor (SNARE) complex of the vesicle fusion apparatus. Binding studies with soluble SNARE complexes have shown that Gßγ binds to both ternary SNARE complexes, t-SNARE heterodimers, and monomeric SNAREs, competing with synaptotagmin 1(syt1) for binding sites on t-SNARE. However, in secretory cells, Gßγ, SNAREs, and synaptotagmin interact in the lipid environment of a vesicle at the plasma membrane. To approximate this environment, we show that fluorescently labeled Gßγ interacts specifically with lipid-embedded t-SNAREs consisting of full-length syntaxin 1 and SNAP-25B at the membrane, as measured by fluorescence polarization. Fluorescently labeled syt1 undergoes competition with Gßγ for SNARE-binding sites in lipid environments. Mutant Gßγ subunits that were previously shown to be more efficacious at inhibiting Ca2+-triggered exocytotic release than wild-type Gßγ were also shown to bind SNAREs at a higher affinity than wild type in a lipid environment. These mutant Gßγ subunits were unable to inhibit VGCC currents. Specific peptides corresponding to regions on Gß and Gγ shown to be important for the interaction disrupt the interaction in a concentration-dependent manner. In in vitro fusion assays using full-length t- and v-SNAREs embedded in liposomes, Gßγ inhibited Ca2+/synaptotagmin-dependent fusion. Together, these studies demonstrate the importance of these regions for the Gßγ-SNARE interaction and show that the target of Gßγ, downstream of VGCC, is the membrane-embedded SNARE complex.


Assuntos
Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Bicamadas Lipídicas , Modelos Moleculares , Proteína 25 Associada a Sinaptossoma/metabolismo , Sinaptotagmina I/metabolismo , Sintaxina 1/metabolismo , Animais , Ligação Competitiva , Sinalização do Cálcio , Bovinos , Linhagem Celular , Subunidades beta da Proteína de Ligação ao GTP/química , Subunidades beta da Proteína de Ligação ao GTP/genética , Subunidades gama da Proteína de Ligação ao GTP/química , Subunidades gama da Proteína de Ligação ao GTP/genética , Humanos , Lipossomos , Fusão de Membrana , Mutação , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Ratos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteína 25 Associada a Sinaptossoma/química , Sinaptotagmina I/química , Sinaptotagmina I/genética , Sintaxina 1/química
5.
J Pharmacol Exp Ther ; 365(2): 219-225, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29491039

RESUMO

Ser54 of Gsα binds guanine nucleotide and Mg2+ as part of a conserved sequence motif in GTP binding proteins. Mutating the homologous residue in small and heterotrimeric G proteins generates dominant-negative proteins, but by protein-specific mechanisms. For αi/o, this results from persistent binding of α to ßγ, whereas for small GTP binding proteins and αs this results from persistent binding to guanine nucleotide exchange factor or receptor. This work examined the role of ßγ interactions in mediating the properties of the Ser54-like mutants of Gα subunits. Unexpectedly, WT-αs or N54-αs coexpressed with α1B-adrenergic receptor in human embryonic kidney 293 cells decreased receptor stimulation of IP3 production by a cAMP-independent mechanism, but WT-αs was more effective than the mutant. One explanation for this result would be that αs, like Ser47 αi/o, blocks receptor activation by sequestering ßγ; implying that N54-αS has reduced affinity for ßγ since it was less effective at blocking IP3 production. This possibility was more directly supported by the observation that WT-αs was more effective than the mutant in inhibiting ßγ activation of phospholipase Cß2. Further, in vitro synthesized N54-αs bound biotinylated-ßγ with lower apparent affinity than did WT-αs The Cys54 mutation also decreased ßγ binding but less effectively than N54-αs Substitution of the conserved Ser in αo with Cys or Asn increased ßγ binding, with the Cys mutant being more effective. This suggests that Ser54 of αs is involved in coupling changes in nucleotide binding with altered subunit interactions, and has important implications for how receptors activate G proteins.


Assuntos
Subunidades alfa Gs de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Mutação , Multimerização Proteica , Subunidades Proteicas/metabolismo , Sequência Conservada , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Células HEK293 , Humanos , Fosfolipase C beta/metabolismo , Ligação Proteica/genética , Estrutura Quaternária de Proteína , Receptores Adrenérgicos alfa 1/metabolismo , Transdução de Sinais
6.
Endoscopy ; 50(8): 770-778, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29614526

RESUMO

BACKGROUND: Direct Observation of Procedural Skills (DOPS) is an established competence assessment tool in endoscopy. In July 2016, the DOPS scoring format changed from a performance-based scale to a supervision-based scale. We aimed to evaluate the impact of changes to the DOPS scale format on the distribution of scores in novice trainees and on competence assessment. METHODS: We performed a prospective, multicenter (n = 276), observational study of formative DOPS assessments in endoscopy trainees with ≤ 100 lifetime procedures. DOPS were submitted in the 6-months before July 2016 (old scale) and after (new scale) for gastroscopy (n = 2998), sigmoidoscopy (n = 1310), colonoscopy (n = 3280), and polypectomy (n = 631). Scores for old and new DOPS were aligned to a 4-point scale and compared. RESULTS: 8219 DOPS (43 % new and 57 % old) submitted for 1300 trainees were analyzed. Compared with old DOPS, the use of the new DOPS was associated with greater utilization of the lowest score (2.4 % vs. 0.9 %; P < 0.001), broader range of scores, and a reduction in competent scores (60.8 % vs. 86.9 %; P < 0.001). The reduction in competent scores was evident on subgroup analysis across all procedure types (P < 0.001) and for each quartile of endoscopy experience. The new DOPS was superior in characterizing the endoscopy learning curve by demonstrating progression of competent scores across quartiles of procedural experience. CONCLUSIONS: Endoscopy assessors applied a greater range of scores using the new DOPS scale based on degree of supervision in two cohorts of trainees matched for experience. Our study provides construct validity evidence in support of the new scale format.


Assuntos
Competência Clínica/normas , Pólipos do Colo/cirurgia , Gastroscopia/normas , Observação , Sigmoidoscopia/normas , Avaliação Educacional/métodos , Gastroscopia/educação , Humanos , Estudos Prospectivos , Sigmoidoscopia/educação
7.
Nucleic Acids Res ; 44(11): 5378-89, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27025650

RESUMO

The NusA protein is a universally conserved bacterial transcription elongation factor that binds RNA polymerase (RNAP). When functioning independently, NusA enhances intrinsic termination. Paradoxically, NusA stimulates the function of the N and Q antiterminator proteins of bacteriophage λ. The mechanistic basis for NusA's functional plasticity is poorly understood. Here we uncover an effect of nascent RNA length on the ability of NusA to collaborate with Q. Ordinarily, Q engages RNAP during early elongation when it is paused at a specific site just downstream of the phage late-gene promoter. NusA facilitates this engagement process and both proteins remain associated with the transcription elongation complex (TEC) as it escapes the pause and transcribes the late genes. We show that the λ-related phage 82 Q protein (82Q) can also engage RNAP that is paused at a promoter-distal position and thus contains a nascent RNA longer than that associated with the natively positioned TEC. However, the effect of NusA in this context is antagonistic rather than stimulatory. Moreover, cleaving the long RNA associated with the promoter-distal TEC restores NusA's stimulatory effect. Our findings reveal a critical role for nascent RNA in modulating NusA's effect on 82Q-mediated antitermination, with implications for understanding NusA's functional plasticity.


Assuntos
Proteínas de Bactérias/metabolismo , RNA/genética , RNA/metabolismo , Terminação da Transcrição Genética , Fatores de Elongação da Transcrição/metabolismo , Proteínas de Bactérias/química , Ligação Competitiva , Modelos Biológicos , Regiões Promotoras Genéticas , Ligação Proteica , Fatores de Elongação da Transcrição/química , Proteínas Virais Reguladoras e Acessórias/química , Proteínas Virais Reguladoras e Acessórias/metabolismo
8.
Proc Natl Acad Sci U S A ; 112(34): 10768-73, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26261308

RESUMO

Th17 responses are critical to a variety of human autoimmune diseases, and therapeutic targeting with monoclonal antibodies against IL-17 and IL-23 has shown considerable promise. Here, we report data to support selective bromodomain blockade of the transcriptional coactivators CBP (CREB binding protein) and p300 as an alternative approach to inhibit human Th17 responses. We show that CBP30 has marked molecular specificity for the bromodomains of CBP and p300, compared with 43 other bromodomains. In unbiased cellular testing on a diverse panel of cultured primary human cells, CBP30 reduced immune cell production of IL-17A and other proinflammatory cytokines. CBP30 also inhibited IL-17A secretion by Th17 cells from healthy donors and patients with ankylosing spondylitis and psoriatic arthritis. Transcriptional profiling of human T cells after CBP30 treatment showed a much more restricted effect on gene expression than that observed with the pan-BET (bromo and extraterminal domain protein family) bromodomain inhibitor JQ1. This selective targeting of the CBP/p300 bromodomain by CBP30 will potentially lead to fewer side effects than with the broadly acting epigenetic inhibitors currently in clinical trials.


Assuntos
Benzimidazóis/farmacologia , Imunossupressores/farmacologia , Interleucina-17/metabolismo , Isoxazóis/farmacologia , Células Th17/efeitos dos fármacos , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Adulto , Idoso , Artrite Psoriásica/metabolismo , Artrite Psoriásica/patologia , Azepinas/farmacologia , Benzimidazóis/química , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Calorimetria , Células Cultivadas , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imunossupressores/química , Interleucina-17/biossíntese , Interleucina-17/genética , Isoxazóis/química , Cinética , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Estrutura Molecular , Conformação Proteica , Estrutura Terciária de Proteína/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Espondilite Anquilosante/metabolismo , Espondilite Anquilosante/patologia , Relação Estrutura-Atividade , Células Th17/imunologia , Triazóis/farmacologia
9.
Nat Chem Biol ; 10(4): 305-12, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24584101

RESUMO

Concomitant inhibition of multiple cancer-driving kinases is an established strategy to improve the durability of clinical responses to targeted therapies. The difficulty of discovering kinase inhibitors with an appropriate multitarget profile has, however, necessitated the application of combination therapies, which can pose major clinical development challenges. Epigenetic reader domains of the bromodomain family have recently emerged as new targets for cancer therapy. Here we report that several clinical kinase inhibitors also inhibit bromodomains with therapeutically relevant potencies and are best classified as dual kinase-bromodomain inhibitors. Nanomolar activity on BRD4 by BI-2536 and TG-101348, which are clinical PLK1 and JAK2-FLT3 kinase inhibitors, respectively, is particularly noteworthy as these combinations of activities on independent oncogenic pathways exemplify a new strategy for rational single-agent polypharmacological targeting. Furthermore, structure-activity relationships and co-crystal structures identify design features that enable a general platform for the rational design of dual kinase-bromodomain inhibitors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/síntese química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Desenho de Fármacos , Polifarmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Western Blotting , Calorimetria , Linhagem Celular Tumoral , Cristalização , Interações Medicamentosas , Ensaios de Seleção de Medicamentos Antitumorais , Epigênese Genética , Ensaios de Triagem em Larga Escala , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Pteridinas/farmacologia , Pirrolidinas/farmacologia , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/farmacologia
10.
Proc Natl Acad Sci U S A ; 110(49): 19754-9, 2013 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-24248379

RESUMO

Bromodomains have emerged as attractive candidates for the development of inhibitors targeting gene transcription. Inhibitors of the bromo and extraterminal (BET) family recently showed promising activity in diverse disease models. However, the pleiotropic nature of BET proteins regulating tissue-specific transcription has raised safety concerns and suggested that attempts should be made for domain-specific targeting. Here, we report that RVX-208, a compound currently in phase II clinical trials, is a BET bromodomain inhibitor specific for second bromodomains (BD2s). Cocrystal structures revealed binding modes of RVX-208 and its synthetic precursor, and fluorescent recovery after photobleaching demonstrated that RVX-208 displaces BET proteins from chromatin. However, gene-expression data showed that BD2 inhibition only modestly affects BET-dependent gene transcription. Our data demonstrate the feasibility of specific targeting within the BET family resulting in different transcriptional outcomes and highlight the importance of BD1 in transcriptional regulation.


Assuntos
Modelos Moleculares , Quinazolinas/química , Quinazolinas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/química , Cristalização , Recuperação de Fluorescência Após Fotodegradação , Células Hep G2 , Humanos , Estrutura Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Ligação Proteica , Estrutura Terciária de Proteína/fisiologia , Quinazolinonas
11.
J Neurosci ; 34(1): 260-74, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24381287

RESUMO

G(i/o)-protein-coupled receptors (GPCRs) ubiquitously inhibit neurotransmission, principally via Gßγ, which acts via a number of possible effectors. GPCR effector specificity has traditionally been attributed to Gα, based on Gα's preferential effector targeting in vitro compared with Gßγ's promiscuous targeting of various effectors. In synapses, however, Gßγ clearly targets unique effectors in a receptor-dependent way to modulate synaptic transmission. It remains unknown whether Gßγ specificity in vivo is due to specific Gßγ isoform-receptor associations or to spatial separation of distinct Gßγ pathways through macromolecular interactions. We thus sought to determine how Gßγ signaling pathways within axons remain distinct from one another. In rat hippocampal CA1 axons, GABA(B) receptors (GABA(B)Rs) inhibit presynaptic Ca(2+) entry, and we have now demonstrated that 5-HT(1B) receptors (5-HT(1B)Rs) liberate Gßγ to interact with SNARE complex C terminals with no effect on Ca(2+) entry. Both GABA(B)Rs and 5-HT(1B)Rs inhibit Ca(2+)-evoked neurotransmitter release, but 5-HT(1B)Rs have no effect on Sr(2+)-evoked release. Sr(2+), unlike Ca(2+), does not cause synaptotagmin to compete with Gßγ binding to SNARE complexes. 5-HT(1B)Rs also fail to inhibit release following cleavage of the C terminus of the SNARE complex protein SNAP-25 with botulinum A toxin. Thus, GABA(B)Rs and 5-HT(1B)Rs both localize to presynaptic terminals, but target distinct effectors. We demonstrate that disruption of SNARE complexes and vesicle priming with botulinum C toxin eliminates this selectivity, allowing 5-HT(1B)R inhibition of Ca(2+) entry. We conclude that receptor-effector specificity requires a microarchitecture provided by the SNARE complex during vesicle priming.


Assuntos
Hipocampo/citologia , Hipocampo/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Proteínas SNARE/fisiologia , Transmissão Sináptica/fisiologia , Animais , Potenciais Pós-Sinápticos Excitadores/fisiologia , Masculino , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Vesículas Sinápticas/fisiologia
12.
J Am Chem Soc ; 136(26): 9308-19, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24946055

RESUMO

Small-molecule inhibitors that target bromodomains outside of the bromodomain and extra-terminal (BET) sub-family are lacking. Here, we describe highly potent and selective ligands for the bromodomain module of the human lysine acetyl transferase CBP/p300, developed from a series of 5-isoxazolyl-benzimidazoles. Our starting point was a fragment hit, which was optimized into a more potent and selective lead using parallel synthesis employing Suzuki couplings, benzimidazole-forming reactions, and reductive aminations. The selectivity of the lead compound against other bromodomain family members was investigated using a thermal stability assay, which revealed some inhibition of the structurally related BET family members. To address the BET selectivity issue, X-ray crystal structures of the lead compound bound to the CREB binding protein (CBP) and the first bromodomain of BRD4 (BRD4(1)) were used to guide the design of more selective compounds. The crystal structures obtained revealed two distinct binding modes. By varying the aryl substitution pattern and developing conformationally constrained analogues, selectivity for CBP over BRD4(1) was increased. The optimized compound is highly potent (Kd = 21 nM) and selective, displaying 40-fold selectivity over BRD4(1). Cellular activity was demonstrated using fluorescence recovery after photo-bleaching (FRAP) and a p53 reporter assay. The optimized compounds are cell-active and have nanomolar affinity for CBP/p300; therefore, they should be useful in studies investigating the biological roles of CBP and p300 and to validate the CBP and p300 bromodomains as therapeutic targets.


Assuntos
Proteína de Ligação a CREB/química , Proteína p300 Associada a E1A/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Sítios de Ligação , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Técnicas de Química Sintética , Cristalografia por Raios X , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos/métodos , Proteína p300 Associada a E1A/metabolismo , Recuperação de Fluorescência Após Fotodegradação , Genes p53 , Células HeLa/efeitos dos fármacos , Humanos , Indóis/química , Isoxazóis/química , Ligantes , Microssomos Hepáticos/efeitos dos fármacos , Modelos Moleculares , Estrutura Molecular , Estrutura Terciária de Proteína , Bibliotecas de Moléculas Pequenas/metabolismo , Relação Estrutura-Atividade
13.
Environ Manage ; 54(1): 30-50, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24788940

RESUMO

Anthropogenic disturbances in wetland ecosystems can alter the composition and structure of plant assemblages and affect system functions. Extensive oil and gas extraction has occurred in wetland habitats along the northern Gulf of Mexico coast since the early 1900s. Activities involved with three-dimensional (3D) seismic exploration for these resources cause various disturbances to vegetation and soils. We documented the impact of a 3D seismic survey in coastal marshes in Louisiana, USA, along transects established before exploration began. Two semi-impounded marshes dominated by Spartina patens were in the area surveyed. Vegetation, soil, and water physicochemical data were collected before the survey, about 6 weeks following its completion, and every 3 months thereafter for 2 years. Soil cores for seed bank emergence experiments were also collected. Maximum vegetation height at impact sites was reduced in both marshes 6 weeks following the survey. In one marsh, total vegetation cover was also reduced, and dead vegetation cover increased, at impact sites 6 weeks after the survey. These effects, however, did not persist 3 months later. No effects on soil or water properties were identified. The total number of seeds that germinated during greenhouse studies increased at impact sites 5 months following the survey in both marshes. Although some seed bank effects persisted 1 year, these effects were not reflected in standing vegetation. The marshes studied were therefore resilient to the impacts resulting from 3D seismic exploration because vegetation responses were short term in that they could not be identified a few months following survey completion.


Assuntos
Indústrias Extrativas e de Processamento/métodos , Vibração/efeitos adversos , Áreas Alagadas , Análise de Variância , Germinação/fisiologia , Louisiana , Gás Natural , Petróleo , Poaceae/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Solo/química , Especificidade da Espécie
14.
Atmos Chem Phys ; 24(2): 1025-1039, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38348019

RESUMO

Future African aerosol emissions, and therefore air pollution levels and health outcomes, are uncertain and understudied. Understanding the future health impacts of pollutant emissions from this region is crucial. Here, this research gap is addressed by studying the range in the future health impacts of aerosol emissions from Africa in the Shared Socioeconomic Pathway (SSP) scenarios, using the UK Earth System Model version 1 (UKESM1), along with human health concentration-response functions. The effects of Africa following a high-pollution aerosol pathway are studied relative to a low-pollution control, with experiments varying aerosol emissions from industry and biomass burning. Using present-day demographics, annual deaths within Africa attributable to ambient particulate matter are estimated to be lower by 150 000 (5th-95th confidence interval of 67 000-234 000) under stronger African aerosol mitigation by 2090, while those attributable to O3 are lower by 15 000 (5th-95th confidence interval of 9000-21 000). The particulate matter health benefits are realised predominantly within Africa, with the O3-driven benefits being more widespread - though still concentrated in Africa - due to the longer atmospheric lifetime of O3. These results demonstrate the important health co-benefits from future emission mitigation in Africa.

15.
Frontline Gastroenterol ; 15(3): 214-221, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38665794

RESUMO

Objective: UK endoscopy training is delivered by trainers possessing well developed endoscopy and teaching skills to help learners perform high-quality endoscopy. Train The Trainer (TTT) courses are effective, but additional trainer support is variable with little formal quality assurance. We performed a survey to map UK endoscopy training, assess trainer perspectives on training delivery and identify factors that would enhance training. Design/Method: An online survey was designed by trainer representatives, in collaboration with the JAG training committee, and collected responses from trainers registered on JAG endoscopy training system e-portfolio from April to June 2022. Results: There were 1024 responses from all trainer disciplines, with 813 (79%) completing TTT courses and 584 (57%) having job planned dedicated training lists (DTLs). Clinical endoscopists most frequently had job-planned DTLs (71%), and DTLs occurring at least weekly (58%). 293 (29%) respondents participated as course faculty. Trainers reported high levels of pre-procedure preparation, effective dialogue and frequent feedback. The DOPS forms were 'always/often' completed by 81% of clinical endoscopists, 73% of gastroenterologist and 58% of surgeons. 435 (42%) trainers never had peer feedback. Responses suggested training could improve by protecting training time, attending courses, participating as faculty and receiving feedback from experienced trainers. Conclusion: This survey demonstrates substantial proportions of highly motivated UK trainers who value time spent teaching and learning how to teach. Skills taught on the TTT courses are often actively used in everyday training. Improved trainer course access, protected training time and formal use of existing feedback tools by peers were highlighted as measures that could support trainers' development.

17.
BMC Gastroenterol ; 13(1): 55, 2013 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-23530737

RESUMO

BACKGROUND: Patients with suspected alcoholic hepatitis and a Discriminant Function ≥32 underwent liver biopsy to confirm the diagnosis. Of these (n = 58), 43 had histological features of alcoholic hepatitis and 15 (25%) did not.We aimed to determine the laboratory features that differentiated those patients with a histological diagnosis of alcoholic hepatitis from those without, and assess potential clinical utility. METHODS: Laboratory investigations at presentation for each of the histologically confirmed cases of alcoholic hepatitis (n = 43) were compared to those without (n = 15) to determine whether there were differences between the two groups. Univariate analysis was by Mann Whitney U Test and Multivariate analysis was by a stepwise approach. RESULTS: White cell count (16.2 ± 10.5 v 6.9 ± 3.5 (× 109/L); p = 0.0001) and platelet count (178 ± 81 v 98.4 ± 43 (× 109/L); p = 0.0005) were higher in the patients with histological features of alcoholic hepatitis than in those without. The area under the ROC curve for AH diagnosis was estimated to be 0.83 (0.73, 0.94) and 0.81 (0.69, 0.93) for white cell count and platelet count respectively. CONCLUSIONS: Clinicians cannot accurately differentiate patients with or without alcoholic hepatitis without liver biopsy. This is critically important when deciding on specific therapies such as corticosteroids or when interpreting data from future trials in which biopsy is not mandated. In situations where liver biopsy is unsuitable or unavailable the white cell and platelet counts can be used to determine the likelihood of histological alcoholic hepatitis and guide treatment.


Assuntos
Alcoolismo/complicações , Hepatite Alcoólica/sangue , Hepatite Alcoólica/diagnóstico , Adulto , Idoso , Algoritmos , Área Sob a Curva , Biomarcadores/sangue , Biópsia , Estudos de Casos e Controles , Feminino , Hepatite Alcoólica/patologia , Humanos , Icterícia/etiologia , Contagem de Leucócitos , Fígado/patologia , Fígado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Contagem de Plaquetas , Curva ROC , Estatísticas não Paramétricas
18.
Regul Toxicol Pharmacol ; 65(1): 47-59, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23123333

RESUMO

Gastrointestinal (GI) symptoms, the primary acute effect of the essential micronutrient copper, paradoxically occur at lower exposure levels than hepatotoxicity, the primary chronic effect. We developed a remedial action criterion (RAC) for copper to protect against GI symptoms, which primarily relate to the stomach copper concentration, and subside within an hour. Using Monte Carlo methods, we generated a distribution of RACs protective against GI symptoms for a 1 h exposure (hourly RACs) based on soil ingestion rate, volume of liquid and food in the stomach, and bioaccessibility. We then generated a distribution of daily RACs, selected as the minimum hourly RAC for each day over a year, constrained by total daily soil ingestion. Next, we identified a percentile of the distribution of daily RACs, and associated RAC, that would result in a high probability of having a minimal number of GI symptom episodes per year. Our analysis indicates that a copper concentration of 3600 mg/kg would result in a 95% probability of having fewer than five episodes of GI symptoms per year, for a child ingesting outdoor soil 180 days per year. Children residing near copper smelters are most likely to experience GI symptoms from ingestion of copper in soil.


Assuntos
Cobre/toxicidade , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/toxicidade , Solo/química , Animais , Criança , Exposição Ambiental/prevenção & controle , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/epidemiologia , Gastroenteropatias/prevenção & controle , Humanos , Metalurgia , Método de Monte Carlo , Probabilidade , Fatores de Tempo
19.
Vaccine ; 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38154993

RESUMO

The COVID-19 Vaccination Provider Oversight (CVPO) program was implemented by the Centers for Disease Control and Prevention (CDC) to ensure the proper management and administration of COVID-19 vaccines by healthcare providers participating in the CDC COVID-19 Vaccination Program. As part of the CVPO program, the 64 CDC-funded immunization program awardees conducted site visits with participating healthcare providers. We evaluated healthcare provider adherence to CVPO program requirements between May 2021 and May 2023. CVPO program site visit data was collected using a REDCap database. The proportion of site visits conducted by U.S. Department of Health and Human Services (HHS) region was calculated. Chi-square statistics for healthcare provider compliance with CVPO program requirements were presented to assess variation in compliance by provider type. The proportion of healthcare providers receiving a site visit ranged from 7.9 % to 37.2 % across HHS regions. Healthcare provider compliance was high for COVID-19 vaccine preparation, administration, and error reporting categories (>90 %). Healthcare provider compliance was lowest for vaccine storage and handling and reporting requirements (79.9 % and 82.6 %, respectively). Public health providers demonstrated significantly higher overall compliance as compared to all other included healthcare provider types (p-value < 0.05). The observed high healthcare provider compliance, coupled with thorough follow-up efforts by awardees to address any non-compliance concerns, highlights the success of jurisdictions supporting healthcare providers with proper vaccine management, administration, and safety procedures. Further research can strengthen vaccine storage, handling, and administration practices for future widespread vaccination efforts.

20.
Oncogene ; 42(10): 748-758, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36611121

RESUMO

The androgen receptor (AR) plays an important role in PCa metabolism, with androgen receptor pathway inhibition (ARPI) subjecting PCa cells to acute metabolic stress caused by reduced biosynthesis and energy production. Defining acute stress response mechanisms that alleviate ARPI stress and therefore mediate prostate cancer (PCa) treatment resistance will help improve therapeutic outcomes of patients treated with ARPI. We identified the up-regulation of chaperone-mediated autophagy (CMA) in response to acute ARPI stress, which persisted in castration-resistant PCa (CRPC); previously undefined in PCa. CMA is a selective protein degradation pathway and a key stress response mechanism up-regulated under several stress stimuli, including metabolic stress. Through selective protein degradation, CMA orchestrates the cellular stress response by regulating cellular pathways through selective proteome remodeling. Through broad-spectrum proteomic analysis, CMA coordinates metabolic reprogramming of PCa cells to sustain PCa growth and survival during ARPI; through the upregulation of mTORC1 signaling and pathways associated with PCa biosynthesis and energetics. This not only promoted PCa growth during ARPI, but also promoted the emergence of CRPC in-vivo. During CMA inhibition, PCa metabolism is compromised, leading to ATP depletion, resulting in a profound anti-proliferative effect on PCa cells, and is enhanced when combined with ARPI. Furthermore, CMA inhibition prevented in-vivo tumour formation, and also re-sensitized enzalutamide-resistant cell lines in-vitro. The profound anti-proliferative effect of CMA inhibition was attributed to cell cycle arrest mediated through p53 transcriptional repression of E2F target genes. In summary, CMA is an acute ARPI stress response mechanism, essential in alleviating ARPI induced metabolic stress, essential for ensuring PCa growth and survival. CMA plays a critical role in the development of ARPI resistance in PCa.


Assuntos
Autofagia Mediada por Chaperonas , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Receptores Androgênicos/genética , Androgênios/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Proteoma , Proteômica , Autofagia , Linhagem Celular Tumoral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA