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1.
Nucleic Acids Res ; 50(1): 350-367, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34928380

RESUMO

Although the RNA helicase Upf1 has hitherto been examined mostly in relation to its cytoplasmic role in nonsense mediated mRNA decay (NMD), here we report high-throughput ChIP data indicating genome-wide association of Upf1 with active genes in Schizosaccharomyces pombe. This association is RNase sensitive, correlates with Pol II transcription and mRNA expression levels. Changes in Pol II occupancy were detected in a Upf1 deficient (upf1Δ) strain, prevalently at genes showing a high Upf1 relative to Pol II association in wild-type. Additionally, an increased Ser2 Pol II signal was detected at all highly transcribed genes examined by ChIP-qPCR. Furthermore, upf1Δ cells are hypersensitive to the transcription elongation inhibitor 6-azauracil. A significant proportion of the genes associated with Upf1 in wild-type conditions are also mis-regulated in upf1Δ. These data envisage that by operating on the nascent transcript, Upf1 might influence Pol II phosphorylation and transcription.


Assuntos
RNA Helicases/metabolismo , RNA Polimerase II/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Regulação Fúngica da Expressão Gênica , Genoma Fúngico , Fosforilação , RNA Helicases/genética , RNA Polimerase II/genética , Schizosaccharomyces , Proteínas de Schizosaccharomyces pombe/genética , Ativação Transcricional
2.
Clin Teach ; 18(5): 529-534, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34132043

RESUMO

BACKGROUND: Inclusion health groups experience a significantly larger burden of morbidity and mortality than the general public. Despite this, undergraduate medical education is often limited in its approach to inclusion health curricula, leaving students disengaged and lacking understanding. METHODS: We conducted two research studies to explore medical students' experiences of inclusion health education. All participants were studying medicine at the University of Leeds at the time of data collection. We gathered experiences of both compulsory and elective inclusion health education via semi-structured interviews. Interview responses were audio-recorded, transcribed and analysed thematically. FINDINGS: We identified several key findings across the two studies. Firstly, medical students felt unprepared to work with inclusion health groups. Further to this, medical students have a preference for interactive teaching and learning in inclusion health education. Finally, encountering inclusion health groups by chance (on placement) or choice (optional initiatives) present different opportunities. DISCUSSION AND CONCLUSION: Our research suggests that simply being exposed to inclusion health groups through lectures and on placement is not considered sufficient by medical students, and in fact can lead to the perpetuation of misinformation and stigma. Participants perceived that optional initiatives or 'choice encounters' had profoundly positive impacts on attitudes and interest, particularly when there were opportunities to learn directly from individuals with lived experience of exclusion. We suggest that a flipped classroom approach to inclusion health education along with integrated experiential learning would provide medical students with comprehensive and patient-focused learning opportunities.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Currículo , Educação em Saúde , Disparidades nos Níveis de Saúde , Humanos
3.
iScience ; 24(2): 102069, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33554071

RESUMO

Glycolysis is a fundamental metabolic pathway for glucose catabolism across biology, and glycolytic enzymes are among the most abundant proteins in cells. Their expression at such levels provides a particular challenge. Here we demonstrate that the glycolytic mRNAs are localized to granules in yeast and human cells. Detailed live cell and smFISH studies in yeast show that the mRNAs are actively translated in granules, and this translation appears critical for the localization. Furthermore, this arrangement is likely to facilitate the higher level organization and control of the glycolytic pathway. Indeed, the degree of fermentation required by cells is intrinsically connected to the extent of mRNA localization to granules. On this basis, we term these granules, core fermentation (CoFe) granules; they appear to represent translation factories, allowing high-level coordinated enzyme synthesis for a critical metabolic pathway.

4.
Angew Chem Int Ed Engl ; 59(44): 19561-19569, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-32648629

RESUMO

Porosity and acidity are influential properties in the rational design of solid-acid catalysts. Probing the physicochemical characteristics of an acidic zeotype framework at the molecular level can provide valuable insights in understanding intrinsic reaction pathways, for affording structure-activity relationships. Herein, we employ a variety of probe-based techniques (including positron annihilation lifetime spectroscopy (PALS), FTIR and solid-state NMR spectroscopy) to demonstrate how a hierarchical design strategy for a faujasitic (FAU) zeotype (synthesized for the first time, via a soft-templating approach, with high phase-purity) can be used to simultaneously modify the porosity and modulate the acidity for an industrially significant catalytic process (Beckmann rearrangement). Detailed characterization of hierarchically porous (HP) SAPO-37 reveals enhanced mass-transport characteristics and moderated acidity, which leads to superior catalytic performance and increased resistance to deactivation by coking, compared to its microporous counterpart, further vindicating the interplay between porosity and moderated acidity.

5.
J Vis Exp ; (152)2019 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-31657795

RESUMO

The adhesion and spreading of cells onto the extracellular matrix (ECM) are essential cellular processes during organismal development and for the homeostasis of adult tissues. Interestingly, oxidative stress can alter these processes, thus contributing to the pathophysiology of diseases such as metastatic cancer. Therefore, understanding the mechanism(s) of how cells attach and spread on the ECM during perturbations in redox status can provide insight into normal and disease states. Described below is a step-wise protocol that utilizes an immunofluorescence-based assay to specifically quantify cell adhesion and spreading of immortalized fibroblast cells on fibronectin (FN) in vitro. Briefly, anchorage-dependent cells are held in suspension and exposed to the ATM kinase inhibitor Ku55933 to induce oxidative stress. Cells are then plated on FN-coated surface and allowed to attach for predetermined periods of time. Cells that remain attached are fixed and labeled with fluorescence-based antibody markers of adhesion (e.g., paxillin) and spreading (e.g., F-actin). Data acquisition and analysis are performed using commonly available laboratory equipment, including an epifluorescence microscope and freely available Fiji software. This procedure is highly versatile and can be modified for a variety of cell lines, ECM proteins, or inhibitors in order to examine a broad range of biological questions.


Assuntos
Adesão Celular/fisiologia , Técnicas de Cultura de Células/métodos , Células Epiteliais/metabolismo , Fibronectinas/metabolismo , Estresse Oxidativo/fisiologia , Animais , Adesão Celular/efeitos dos fármacos , Contagem de Células/métodos , Linhagem Celular , Linhagem Celular Transformada , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Microscopia de Fluorescência/métodos , Morfolinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Pironas/farmacologia
6.
Ecotoxicol Environ Saf ; 141: 1-8, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28284150

RESUMO

The sea cucumber Stichopus horrens is an important component of near-shore ecosystems, and in the Kingdom of Tonga it also comprises an important commercial and subsistence fishery. To assess the sensitivity of this species to the toxic trace metal cadmium (Cd), adult S. horrens were exposed for 96h to an environmental (15µgL-1) or effect (765µgL-1) concentration of waterborne Cd. The respiratory tree and intestine accumulated higher concentrations of Cd than the muscle and body wall, but there were no effects of Cd on tissue ions (sodium, potassium, magnesium, calcium). For comparison, Cd accumulation was also examined in the Australasian sea cucumber Australostichopus mollis. This species displayed a similar pattern of tissue-specific accumulation to S. horrens, but exhibited lower tissue Cd burdens, likely a consequence of lower experimental temperature. Effects on gonad ion content were also seen in this species. At the highest Cd exposure concentration, S. horrens showed impaired ammonia excretion rates and an increased molar oxygen:nitrogen ratio (O:N), indicative of a decreased reliance on protein metabolism. Overall, this study suggests that S. horrens is relatively tolerant of Cd exposure, but raises concerns regarding the subsistence fishery practice of consuming the viscera of this species.


Assuntos
Cádmio/toxicidade , Metabolismo Energético/efeitos dos fármacos , Stichopus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Amônia/metabolismo , Animais , Cádmio/metabolismo , Stichopus/metabolismo , Poluentes Químicos da Água/metabolismo
7.
Eur J Pharmacol ; 714(1-3): 193-201, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23796957

RESUMO

Folic acid enhances endothelial function and improves outcome in primary prevention of cardiovascular disease. The exact intracellular signalling mechanisms involved remain elusive and were therefore the subject of this study. Particular focus was placed on folic acid-induced changes in posttranslational modifications of endothelial nitric oxide synthase (eNOS). Cultured endothelial cells were exposed to folic acid in the absence or presence of phosphatidylinositol-3' kinase/Akt (PI3K/Akt) inhibitors. The phosphorylation status of eNOS was determined via western blotting. The activities of eNOS and PI3K/Akt were evaluated. The interaction of eNOS with caveolin-1, Heat-Shock Protein 90 and calmodulin was studied using co-immunoprecipitation. Intracellular localisation of eNOS was investigated using sucrose gradient centrifugation and confocal microscopy. Folic acid promoted eNOS dephosphorylation at negative regulatory sites, and increased phosphorylation at positive regulatory sites. Modulation of phosphorylation status was concomitant with increased cGMP concentrations, and PI3K/Akt activity. Inhibition of PI3K/Akt revealed specific roles for this kinase pathway in folic acid-mediated eNOS phosphorylation. Regulatory protein and eNOS protein associations were altered in favour of a positive regulatory effect in the absence of bulk changes in intracellular eNOS localisation. Folic acid-mediated eNOS activation involves the modulation of eNOS phosphorylation status at multiple residues and positive changes in important protein-protein interactions. Such intracellular mechanisms may in part explain improvements in clinical vascular outcome following folic acid treatment.


Assuntos
Cardiotônicos/farmacologia , Ácido Fólico/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Animais , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Suínos
8.
Vasc Endovascular Surg ; 46(3): 223-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22492108

RESUMO

AIM: The aim of this study was to compare midterm mortality between anemic and nonanemic patients undergoing endovascular repair of abdominal aortic aneurysm and to assess a correlation with markers of inflammation. METHODS: Anemia was defined as hemoglobin <13 (men) and <12 g/dL (women). The impact of anemia and inflammatory markers on mortality was assessed using Kaplan-Meier curves and Cox regression. RESULTS: A total of 224 patients (12 females [5.36%]; age: 69.73 ± 8.72 years) were included; 102 (45.53%) were anemic. Median follow-up was 17 months (interquartile range: 7-25 months). Nine patients died (1.79%; 8 anemic vs 1 nonanemic). Survival was lower for patients with anemia (log-rank, P = .01). White blood cell count and C-reactive protein (CRP) differed significantly (P < .001 and P = .01). Anemia and CRP were associated with decreased survival (Cox regression, P = .01, hazard ratio [HR]: 0.35, 95% confidence interval: 0.14-0.84 and P = .002, HR: 1.18, 95% CI: 1.06-1.31). CONCLUSION: Patients with anemia had decreased survival over the midterm; inflammatory markers were higher among this group.


Assuntos
Anemia/mortalidade , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/mortalidade , Idoso , Anemia/sangue , Aneurisma da Aorta Abdominal/sangue , Aneurisma da Aorta Abdominal/mortalidade , Biomarcadores/sangue , Implante de Prótese Vascular/efeitos adversos , Proteína C-Reativa/metabolismo , Comorbidade , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Mediadores da Inflamação/sangue , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Reino Unido/epidemiologia , Regulação para Cima
9.
J Endovasc Ther ; 18(5): 697-715, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21992642

RESUMO

Isolated common iliac artery aneurysms (CIAAs) are relatively rare; they typically progress asymptomatically and are revealed incidentally, usually after they have acquired significant dimensions. Traditional open reconstruction is associated with high morbidity and mortality rates. Rupture is a common initial manifestation. Endovascular repair has been proposed as a minimally invasive alternative, associated with lower morbidity and mortality rates, even in patients at high surgical risk; some specialists have recently proposed endoluminal repair as the first-choice procedure in suitable anatomies. However, only a few sporadic attempts have been made to define the "suitable" anatomy for endovascular repair. This article proposes a classification of isolated CIAAs and provides endovascular specialists with a guide to deciding which type of repair is feasible and efficacious according to the anatomical configuration of the aneurysm.


Assuntos
Implante de Prótese Vascular , Procedimentos Endovasculares , Aneurisma Ilíaco/classificação , Aneurisma Ilíaco/cirurgia , Terminologia como Assunto , Implante de Prótese Vascular/efeitos adversos , Técnicas de Apoio para a Decisão , Procedimentos Endovasculares/efeitos adversos , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Seleção de Pacientes , Radiografia , Medição de Risco , Fatores de Risco
10.
Perspect Vasc Surg Endovasc Ther ; 22(4): 245-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21411464

RESUMO

Popliteal artery aneurysm (PAA), despite being rare, is the most common peripheral aneurysm. It can present as acute thrombosis and occlusion of the aneurysmal segment, and distal embolization, causing either chronic or acute limb ischemia. It has traditionally been treated with open surgical reconstruction. Endovascular repair of PAAs has recently been applied electively with a favourable early and mid-term outcome; however there is a lack of reports on the endovascular treatment of PAAs presenting with acute complications. This report describes the treatment of a thrombosed PAA in a 58 year old male using an endovascular stent-graft and also provides a systematic review of the literature on the emergency endovascular treatment of PAAs.


Assuntos
Aneurisma/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Artéria Poplítea/cirurgia , Aneurisma/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Poplítea/diagnóstico por imagem , Radiografia , Resultado do Tratamento
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