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1.
Artigo em Inglês | MEDLINE | ID: mdl-39301225

RESUMO

Wearable Cameras (WCs) enable researchers to capture objective descriptions of what participants see and experience as they go about their normal lives. When studying interactions between individuals (e.g. between a parent and child), using multiple WCs can provide highly detailed descriptions of interactions with levels of ecological validity not possible with other methods. However, the use of WCs brings challenges too, and understanding these is key to developing and optimising these methods. We captured the challenges experienced by a variety of stakeholders, namely parents and a range of different researcher roles (academics, field-workers and data processors) involved in a large UK study exploring parent-child interactions using low-cost, off-the-shelf WCs. High among the challenges identified were difficulties caused when subjects are temporarily not in view in the video footage captured. This and other factors identified were used as criteria to select a new, improved WC. The new WCs reduced the time faces were not in view by 75%. We report this and the other challenges identified, and suggest how these can be used to guide and help optimise future studies of this kind.

2.
Cell Mol Life Sci ; 79(5): 265, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484438

RESUMO

Alcoholic pancreatitis and hepatitis are frequent, potentially lethal diseases with limited treatment options. Our previous study reported that the expression of CFTR Cl- channel is impaired by ethanol in pancreatic ductal cells leading to more severe alcohol-induced pancreatitis. In addition to determining epithelial ion secretion, CFTR has multiple interactions with other proteins, which may influence intracellular Ca2+ signaling. Thus, we aimed to investigate the impact of ethanol-mediated CFTR damage on intracellular Ca2+ homeostasis in pancreatic ductal epithelial cells and cholangiocytes. Human and mouse pancreas and liver samples and organoids were used to study ion secretion, intracellular signaling, protein expression and interaction. The effect of PMCA4 inhibition was analyzed in a mouse model of alcohol-induced pancreatitis. The decreased CFTR expression impaired PMCA function and resulted in sustained intracellular Ca2+ elevation in ethanol-treated and mouse and human pancreatic organoids. Liver samples derived from alcoholic hepatitis patients and ethanol-treated mouse liver organoids showed decreased CFTR expression and function, and impaired PMCA4 activity. PMCA4 co-localizes and physically interacts with CFTR on the apical membrane of polarized epithelial cells, where CFTR-dependent calmodulin recruitment determines PMCA4 activity. The sustained intracellular Ca2+ elevation in the absence of CFTR inhibited mitochondrial function and was accompanied with increased apoptosis in pancreatic epithelial cells and PMCA4 inhibition increased the severity of alcohol-induced AP in mice. Our results suggest that improving Ca2+ extrusion in epithelial cells may be a potential novel therapeutic approach to protect the exocrine pancreatic function in alcoholic pancreatitis and prevent the development of cholestasis in alcoholic hepatitis.


Assuntos
Hepatite Alcoólica , Hepatite , Pancreatite Alcoólica , Animais , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Células Epiteliais/metabolismo , Etanol/toxicidade , Hepatite/metabolismo , Hepatite Alcoólica/genética , Hepatite Alcoólica/metabolismo , Humanos , Camundongos , Pancreatite Alcoólica/metabolismo
3.
SLAS Discov ; 26(7): 909-921, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34085560

RESUMO

A core aspect of epithelial cell function is barrier integrity. A loss of barrier integrity is a feature of a number of respiratory diseases, including asthma, allergic rhinitis, and chronic obstructive pulmonary disease. Restoration of barrier integrity is a target for respiratory disease drug discovery. Traditional methods for assessing barrier integrity have their limitations. Transepithelial electrical resistance (TEER) and dextran permeability methods can give poor in vitro assay robustness. Traditional junctional complex imaging approaches are labor-intensive and tend to be qualitative but not quantitative. To provide a robust and quantitative assessment of barrier integrity, high-content imaging of junctional complexes was combined with TEER. A scalable immunofluorescent high-content imaging technique, with automated quantification of junctional complex proteins zonula occludens-1 and occludin, was established in 3D pseudostratified primary human bronchial epithelial cells cultured at an air-liquid interface. Ionic permeability was measured using TEER on the same culture wells.The improvements to current technologies include the design of a novel 24-well holder to enable scalable in situ confocal cell imaging without Transwell membrane excision, the development of image analysis pipelines to quantify in-focus junctional complex structures in each plane of a Z stack, and the enhancement of the TEER data analysis process to enable statistical evaluation of treatment effects on barrier integrity. This novel approach was validated by demonstrating measurable changes in barrier integrity in cells grown under conditions known to perturb epithelial cell function.


Assuntos
Epitélio/fisiologia , Junções Intercelulares/metabolismo , Células Cultivadas , Impedância Elétrica , Células Epiteliais , Humanos , Imagem Molecular/métodos , Complexos Multiproteicos , Permeabilidade
4.
J Clin Endocrinol Metab ; 105(5)2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748811

RESUMO

CONTEXT: Although diabetes affects 40% to 50% of adults with cystic fibrosis, remarkably little is known regarding the underlying mechanisms leading to impaired pancreatic ß-cell insulin secretion. Efforts toward improving the functional ß-cell deficit in cystic fibrosis-related diabetes (CFRD) have been hampered by an incomplete understanding of whether ß-cell function is intrinsically regulated by cystic fibrosis transmembrane conductance regulator (CFTR). Definitively excluding meaningful CFTR expression in human ß-cells in situ would contribute significantly to the understanding of CFRD pathogenesis. OBJECTIVE: To determine CFTR messenger ribonucleic acid (mRNA) and protein expression within ß-cells in situ in the unmanipulated human pancreas of donors without any known pancreatic pathology. DESIGN: In situ hybridization for CFTR mRNA expression in parallel with insulin immunohistochemical staining and immunofluorescence co-localization of CFTR with insulin and the ductal marker, Keratin-7 (KRT7), were undertaken in pancreatic tissue blocks from 10 normal adult, nonobese deceased organ donors over a wide age range (23-71 years) with quantitative image analysis. RESULTS: CFTR mRNA was detectable in a mean 0.45% (range 0.17%-0.83%) of insulin-positive cells. CFTR protein expression was co-localized with KRT7. One hundred percent of insulin-positive cells were immunonegative for CFTR. CONCLUSIONS: For the first time, in situ CFTR mRNA expression in the unmanipulated pancreas has been shown to be present in only a very small minority (<1%) of normal adult ß-cells. These data signal a need to move away from studying endocrine-intrinsic mechanisms and focus on elucidation of exocrine-endocrine interactions in human cystic fibrosis.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Células Secretoras de Insulina/metabolismo , Pâncreas/metabolismo , Adulto , Idoso , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos , Autopsia , Contagem de Células , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Feminino , Furões , Técnicas de Inativação de Genes , Humanos , Células Secretoras de Insulina/patologia , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Adulto Jovem
5.
Inorg Chem ; 58(15): 10287-10294, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31335126

RESUMO

In aqueous media, hydrophobic metallocorroles form nanoparticles that are potential theranostic anticancer agents. We have analyzed the electronic and Raman spectra of Al(III), Ga(III), and Au(III) corrole nanoparticles (and made comparisons with DFT-validated assignments of the IR spectra of corresponding monomers) in order to estimate the strengths of corrole-corrole electronic couplings in these assemblies. We find that these spectra are virtually unchanged upon aggregation, confirming that the intermolecular interactions in these nanoparticles are very weak.

6.
Med Sci Sports Exerc ; 51(5): 1047-1054, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30985585

RESUMO

PURPOSE: Preparticipation health screening is recommended to detect individuals susceptible to serious adverse cardiovascular complications during exercise. Although expert opinion and best available scientific evidence have informed recent modifications, there remain limited experimental data to support or refute current practice. We therefore aimed to quantify the impact of change to the preparticipation health screening guidelines of the American College of Sports Medicine (ACSM) on risk classification and referral for medical clearance in a large cohort of undergraduate university students. METHODS: Participants attended the laboratory on a single occasion to undergo preparticipation health screening. Information concerning health status was obtained via self-report questionnaire and objective physiological assessment with all data recorded electronically and evaluated against the ACSM screening guidelines (9th and 10th editions). RESULTS: Five hundred and fifty-three students completed the study. The 9th edition screening guidance resulted in 82 subjects (15%) classified as high risk, almost one-quarter (24%) classified as moderate risk, and almost two-thirds (61%) classified as low risk. In comparison, the updated 10th edition screening guidance resulted in a significant reduction in those previously classified as either high risk (5%) or moderate risk (2%), respectively. The majority of subjects (93%) were therefore cleared to begin a structured exercise program. Taken together, approximately one-third (32%) fewer medical referrals were required when applying the updated 10th edition guidance (χ4 = 247.7, P < 0.001). CONCLUSIONS: The updated ACSM 10th edition preparticipation screening guidance reduces medical referrals by approximately one-third. These findings are in keeping with previous reports and thus serve to consolidate and justify recent modification-particularly when applied to young adult or adolescent populations. The findings and arguments presented should be used to refine and inform future guidance.


Assuntos
Exame Físico/normas , Guias de Prática Clínica como Assunto , Medição de Risco/métodos , Medicina Esportiva/normas , Adolescente , Doenças Cardiovasculares/diagnóstico , Feminino , Nível de Saúde , Humanos , Masculino , Sociedades Médicas , Estudantes , Inquéritos e Questionários , Reino Unido , Universidades , Adulto Jovem
7.
Gastroenterology ; 148(2): 427-39.e16, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25447846

RESUMO

BACKGROUND & AIMS: Excessive consumption of ethanol is one of the most common causes of acute and chronic pancreatitis. Alterations to the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) also cause pancreatitis. However, little is known about the role of CFTR in the pathogenesis of alcohol-induced pancreatitis. METHODS: We measured CFTR activity based on chloride concentrations in sweat from patients with cystic fibrosis, patients admitted to the emergency department because of excessive alcohol consumption, and healthy volunteers. We measured CFTR levels and localization in pancreatic tissues and in patients with acute or chronic pancreatitis induced by alcohol. We studied the effects of ethanol, fatty acids, and fatty acid ethyl esters on secretion of pancreatic fluid and HCO3(-), levels and function of CFTR, and exchange of Cl(-) for HCO3(-) in pancreatic cell lines as well as in tissues from guinea pigs and CFTR knockout mice after administration of alcohol. RESULTS: Chloride concentrations increased in sweat samples from patients who acutely abused alcohol but not in samples from healthy volunteers, indicating that alcohol affects CFTR function. Pancreatic tissues from patients with acute or chronic pancreatitis had lower levels of CFTR than tissues from healthy volunteers. Alcohol and fatty acids inhibited secretion of fluid and HCO3(-), as well as CFTR activity, in pancreatic ductal epithelial cells. These effects were mediated by sustained increases in concentrations of intracellular calcium and adenosine 3',5'-cyclic monophosphate, depletion of adenosine triphosphate, and depolarization of mitochondrial membranes. In pancreatic cell lines and pancreatic tissues of mice and guinea pigs, administration of ethanol reduced expression of CFTR messenger RNA, reduced the stability of CFTR at the cell surface, and disrupted folding of CFTR at the endoplasmic reticulum. CFTR knockout mice given ethanol or fatty acids developed more severe pancreatitis than mice not given ethanol or fatty acids. CONCLUSIONS: Based on studies of human, mouse, and guinea pig pancreata, alcohol disrupts expression and localization of the CFTR. This appears to contribute to development of pancreatitis. Strategies to increase CFTR levels or function might be used to treat alcohol-associated pancreatitis.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Etanol/toxicidade , Pancreatite/induzido quimicamente , Trifosfato de Adenosina/análise , Animais , Bicarbonatos/metabolismo , Cálcio/metabolismo , Canais de Cloreto/antagonistas & inibidores , Regulador de Condutância Transmembrana em Fibrose Cística/análise , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Cobaias , Humanos , Camundongos , Mutação , Dobramento de Proteína/efeitos dos fármacos
8.
Crit Care Med ; 42(3): e177-88, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24368347

RESUMO

OBJECTIVES: A common potentially fatal disease of the pancreas is acute pancreatitis, for which there is no treatment. Most studies of this disorder focus on the damage to acinar cells since they are assumed to be the primary target of multiple stressors affecting the pancreas. However, increasing evidence suggests that the ducts may also have a crucial role in induction of the disease. To test this hypothesis, we sought to determine the specific role of the duct in the induction of acute pancreatitis using well-established disease models and mice with deletion of the Na/H exchanger regulatory factor-1 that have selectively impaired ductal function. DESIGN: Randomized animal study. SETTING: Animal research laboratory. SUBJECTS: Wild-type and Na/H exchanger regulatory factor-1 knockout mice. INTERVENTIONS: Acute necrotizing pancreatitis was induced by i.p. administration of cerulein or by intraductal administration of sodium taurocholate. The pancreatic expression of Na/H exchanger regulatory factor-1 and cystic fibrosis transmembrane conductance regulator (a key player in the control of ductal secretion) was analyzed by immunohistochemistry. In vivo pancreatic ductal secretion was studied in anesthetized mice. Functions of pancreatic acinar and ductal cells as well as inflammatory cells were analyzed in vitro. MEASUREMENTS AND MAIN RESULTS: Deletion of Na/H exchanger regulatory factor-1 resulted in gross mislocalization of cystic fibrosis transmembrane conductance regulator, causing marked reduction in pancreatic ductal fluid and bicarbonate secretion. Importantly, deletion of Na/H exchanger regulatory factor-1 had no deleterious effect on functions of acinar and inflammatory cells. Deletion of Na/H exchanger regulatory factor-1, which specifically impaired ductal function, increased the severity of acute pancreatitis in the two mouse models tested. CONCLUSIONS: Our findings provide the first direct evidence for the crucial role of ductal secretion in protecting the pancreas from acute pancreatitis and strongly suggest that improved ductal function should be an important modality in prevention and treatment of the disease.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Ductos Pancreáticos/metabolismo , Pancreatite Necrosante Aguda/metabolismo , Pancreatite Necrosante Aguda/patologia , Fosfoproteínas/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Sistemas de Transporte de Aminoácidos/metabolismo , Animais , Biomarcadores/metabolismo , Distribuição de Qui-Quadrado , Modelos Animais de Doenças , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Pâncreas/metabolismo , Pâncreas/fisiologia , RNA Mensageiro/metabolismo , Distribuição Aleatória , Valores de Referência , Regeneração/fisiologia , Sensibilidade e Especificidade , Simportadores/metabolismo
9.
Environ Toxicol Chem ; 32(3): 653-61, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23233343

RESUMO

A comprehensive biological, sediment, and water quality study of the lower Little Scioto River near Marion, Ohio, USA, was undertaken to evaluate the changes or improvements in biotic measurements following the removal of creosote-contaminated sediment. The study area covered 7.5 river miles (RMs), including a remediated section between RMs 6.0 and 6.8. Fish and macroinvertebrate assemblages, fish biomarkers (i.e., polycyclic aromatic hydrocarbon [PAH] metabolite levels in white sucker [Castostomus commersoni] and common carp [Cyprinus carpio] bile and DNA damage), sediment chemistry, and water quality were assessed at five locations relative to the primary source of historical PAH contamination-upstream (RM 9.2), adjacent (RM 6.5), and downstream (RMs 5.7, 4.4, and 2.7). Overall, the biomarker results were consistent with the sediment PAH results, showing a pattern of low levels of PAH bile metabolites and DNA damage at the upstream (reference or background location), as well as the remediated section, high levels at the two immediate downstream sites, and somewhat lower levels at the furthest downstream site. Results show that remediation was effective in reducing sediment contaminant concentrations and exposure of fish to PAHs and in improving fish assemblages (60% increase in index of biotic integrity scores) in remediated river sections. Additional remedial investigation and potentially further remediation is needed to improve the downstream benthic fish community, which is still heavily exposed to PAH contaminants.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Peixes/metabolismo , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Animais , Biomarcadores/metabolismo , Creosoto/análise , Creosoto/metabolismo , Creosoto/toxicidade , Dano ao DNA , Ohio , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Rios/química , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Qualidade da Água
10.
Gastroenterology ; 141(6): 2228-2239.e6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21893120

RESUMO

BACKGROUND & AIMS: The effects of trypsin on pancreatic ductal epithelial cells (PDECs) vary among species and depend on the localization of proteinase-activated receptor 2 (PAR-2). We compared PAR-2 localization in human and guinea-pig PDECs, and used isolated guinea pig ducts to study the effects of trypsin and a PAR-2 agonist on bicarbonate secretion. METHODS: PAR-2 localization was analyzed by immunohistochemistry in guinea pig and human pancreatic tissue samples (from 15 patients with chronic pancreatitis and 15 without pancreatic disease). Functionally, guinea pig PDECs were studied by microperfusion of isolated ducts, measurements of intracellular pH and intracellular Ca(2+) concentration, and patch clamp analysis. The effect of pH on trypsinogen autoactivation was assessed using recombinant human cationic trypsinogen. RESULTS: PAR-2 localized to the apical membrane of human and guinea pig PDECs. Trypsin increased intracellular Ca(2+) concentration and intracellular pH and inhibited secretion of bicarbonate by the luminal anion exchanger and the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel. Autoactivation of human cationic trypsinogen accelerated when the pH was reduced from 8.5 to 6.0. PAR-2 expression was strongly down-regulated, at transcriptional and protein levels, in the ducts of patients with chronic pancreatitis, consistent with increased activity of intraductal trypsin. Importantly, in PAR-2 knockout mice, the effects of trypsin were markedly reduced. CONCLUSIONS: Trypsin reduces pancreatic ductal bicarbonate secretion via PAR-2-dependent inhibition of the apical anion exchanger and the CFTR Cl(-) channel. This could contribute to the development of chronic pancreatitis by decreasing luminal pH and promoting premature activation of trypsinogen in the pancreatic ducts.


Assuntos
Bicarbonatos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/antagonistas & inibidores , Ductos Pancreáticos/metabolismo , Pancreatite Crônica/enzimologia , Receptor PAR-2/metabolismo , Tripsina/fisiologia , Animais , Resinas de Troca Aniônica/metabolismo , Ativação Enzimática , Células Epiteliais/metabolismo , Cobaias , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ductos Pancreáticos/citologia , Pancreatite Crônica/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor PAR-2/antagonistas & inibidores , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tripsinogênio/metabolismo
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