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1.
Nucleic Acids Res ; 51(D1): D977-D985, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36350656

RESUMO

The NHGRI-EBI GWAS Catalog (www.ebi.ac.uk/gwas) is a FAIR knowledgebase providing detailed, structured, standardised and interoperable genome-wide association study (GWAS) data to >200 000 users per year from academic research, healthcare and industry. The Catalog contains variant-trait associations and supporting metadata for >45 000 published GWAS across >5000 human traits, and >40 000 full P-value summary statistics datasets. Content is curated from publications or acquired via author submission of prepublication summary statistics through a new submission portal and validation tool. GWAS data volume has vastly increased in recent years. We have updated our software to meet this scaling challenge and to enable rapid release of submitted summary statistics. The scope of the repository has expanded to include additional data types of high interest to the community, including sequencing-based GWAS, gene-based analyses and copy number variation analyses. Community outreach has increased the number of shared datasets from under-represented traits, e.g. cancer, and we continue to contribute to awareness of the lack of population diversity in GWAS. Interoperability of the Catalog has been enhanced through links to other resources including the Polygenic Score Catalog and the International Mouse Phenotyping Consortium, refinements to GWAS trait annotation, and the development of a standard format for GWAS data.


Assuntos
Estudo de Associação Genômica Ampla , Bases de Conhecimento , Animais , Humanos , Camundongos , Variações do Número de Cópias de DNA , National Human Genome Research Institute (U.S.) , Fenótipo , Polimorfismo de Nucleotídeo Único , Software , Estados Unidos
2.
ERJ Open Res ; 8(4)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36478917

RESUMO

Introduction: Early eradication of methicillin-resistant Staphylococcus aureus (MRSA) in cystic fibrosis is desirable. Prospective studies are challenging owing to the feasibility of recruiting patients with a rare event in an orphan disease. Our prior randomised study (Staph Aureus Resistance-Treat Or Observe (STAR-too)) showed improved clearance and outcomes with aggressive therapy compared to no treatment. We present a novel trial design to guide treatment for eradicating incident infection with a focus on feasibility. Methods: Subjects with cystic fibrosis with incident MRSA infection were enrolled into the Staph Aureus Resistance-Treat Early And Repeat (STAR-ter) protocol and treated with a combination of an oral antibiotic and topical (nare and throat) decolonisation. The primary outcome was MRSA-negative respiratory culture at Day 28, i.e. 14 days after completion of oral antibiotics. What was novel about this study design was that the control/comparator group was the untreated group of the STAR-too trial. This design was developed because having a "no treatment" group would be unethical given prior findings and a superiority design would delay the time to results based on small numbers of eligible subjects. Both studies used the same inclusion and exclusion criteria and drew subjects from the same geographic regions. The main difference between the studies was the use of a single oral antibiotic, trimethoprim-sulfamethoxazole, rather than the combination with oral rifampin used in STAR-too. Discussion: An innovative approach to address a clinical question for a rare event in an orphan disease, cystic fibrosis, is presented to enhance current clinical evidence to guide cystic fibrosis care in relation to new MRSA infection.

3.
ERJ Open Res ; 7(4)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34646879

RESUMO

Lessons learnt from the pandemic show that telehealth for cystic fibrosis allows multidisciplinary visits but better means for monitoring of lung function and microbiology are needed https://bit.ly/2V7g09x.

4.
Am J Physiol Cell Physiol ; 317(6): C1093-C1106, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31461344

RESUMO

This study explored the mechanism by which Ca2+-activated Cl- channels (CaCCs) encoded by the Tmem16a gene are regulated by calmodulin-dependent protein kinase II (CaMKII) and protein phosphatases 1 (PP1) and 2A (PP2A). Ca2+-activated Cl- currents (IClCa) were recorded from HEK-293 cells expressing mouse TMEM16A. IClCa were evoked using a pipette solution in which free Ca2+ concentration was clamped to 500 nM, in the presence (5 mM) or absence of ATP. With 5 mM ATP, IClCa decayed to <50% of the initial current magnitude within 10 min after seal rupture. IClCa rundown seen with ATP-containing pipette solution was greatly diminished by omitting ATP. IClCa recorded after 20 min of cell dialysis with 0 ATP were more than twofold larger than those recorded with 5 mM ATP. Intracellular application of autocamtide-2-related inhibitory peptide (5 µM) or KN-93 (10 µM), two specific CaMKII inhibitors, produced a similar attenuation of TMEM16A rundown. In contrast, internal application of okadaic acid (30 nM) or cantharidin (100 nM), two nonselective PP1 and PP2A blockers, promoted the rundown of TMEM16A in cells dialyzed with 0 ATP. Mutating serine 528 of TMEM16A to an alanine led to a similar inhibition of TMEM16A rundown to that exerted by either one of the two CaMKII inhibitors tested, which was not observed for three putative CaMKII consensus sites for phosphorylation (T273, T622, and S730). Our results suggest that TMEM16A-mediated CaCCs are regulated by CaMKII and PP1/PP2A. Our data also suggest that serine 528 of TMEM16A is an important contributor to the regulation of IClCa by CaMKII.


Assuntos
Anoctamina-1/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Regulação da Expressão Gênica , Proteínas de Neoplasias/genética , Proteína Fosfatase 1/genética , Proteína Fosfatase 2/genética , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Sequência de Aminoácidos , Animais , Anoctamina-1/metabolismo , Benzilaminas/farmacologia , Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cantaridina/farmacologia , Cloretos/metabolismo , Potenciais Evocados/efeitos dos fármacos , Potenciais Evocados/fisiologia , Células HEK293 , Humanos , Transporte de Íons/efeitos dos fármacos , Camundongos , Proteínas de Neoplasias/metabolismo , Ácido Okadáico/farmacologia , Técnicas de Patch-Clamp , Peptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 1/antagonistas & inibidores , Proteína Fosfatase 1/metabolismo , Proteína Fosfatase 2/antagonistas & inibidores , Proteína Fosfatase 2/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Sulfonamidas/farmacologia
5.
Curr Eye Res ; 44(8): 813-822, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31055948

RESUMO

There is growing evidence that placental growth factor (PlGF) is an important player in multiple pathologies, including tumorigenesis, inflammatory disorders and degenerative retinopathies. PlGF is a member of the vascular endothelial growth factor (VEGF) family and in the retina, binding of this growth factor to specific receptors is associated with pathological angiogenesis, vascular leakage, neurodegeneration and inflammation. Although they share some receptor signalling pathways, many of the actions of PlGF are distinct from VEGF and this has revealed the enticing prospect that it could be a useful therapeutic target for treating early and late stages of diabetic retinopathy (DR) and neovascular age-related macular degeneration (AMD). Recent research suggests that modulation of PlGF could also be important in the geographic atrophy (GA) form of late AMD by protecting the outer retina and the retinal pigment epithelium (RPE). This review discusses PlGF and its signalling pathways and highlights the potential of blocking the bioactivity of this growth factor to treat irreversible visual loss due to the two main forms of AMD.


Assuntos
Degeneração Macular/fisiopatologia , Fator de Crescimento Placentário/fisiologia , Transdução de Sinais/fisiologia , Células Epiteliais Alveolares/fisiologia , Humanos , Epitélio Pigmentado da Retina/fisiologia
6.
Nat Commun ; 10(1): 1150, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850646

RESUMO

Frontal fibrosing alopecia (FFA) is a recently described inflammatory and scarring type of hair loss affecting almost exclusively women. Despite a dramatic recent increase in incidence the aetiopathogenesis of FFA remains unknown. We undertake genome-wide association studies in females from a UK cohort, comprising 844 cases and 3,760 controls, a Spanish cohort of 172 cases and 385 controls, and perform statistical meta-analysis. We observe genome-wide significant association with FFA at four genomic loci: 2p22.2, 6p21.1, 8q24.22 and 15q2.1. Within the 6p21.1 locus, fine-mapping indicates that the association is driven by the HLA-B*07:02 allele. At 2p22.1, we implicate a putative causal missense variant in CYP1B1, encoding the homonymous xenobiotic- and hormone-processing enzyme. Transcriptomic analysis of affected scalp tissue highlights overrepresentation of transcripts encoding components of innate and adaptive immune response pathways. These findings provide insight into disease pathogenesis and characterise FFA as a genetically predisposed immuno-inflammatory disorder driven by HLA-B*07:02.


Assuntos
Alopecia/congênito , Loci Gênicos , Predisposição Genética para Doença , Antígeno HLA-B7/genética , Transcriptoma/imunologia , Imunidade Adaptativa , Alopecia/diagnóstico , Alopecia/genética , Alopecia/fisiopatologia , Estudos de Casos e Controles , Estudos de Coortes , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/imunologia , Feminino , Expressão Gênica , Genoma Humano , Estudo de Associação Genômica Ampla , Antígeno HLA-B7/imunologia , Humanos , Imunidade Inata , Polimorfismo de Nucleotídeo Único
7.
Prog Retin Eye Res ; 69: 116-136, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30385175

RESUMO

Placental growth factor (PlGF) is a member of the vascular endothelial growth factor (VEGF) family. Upon binding to VEGF- and neuropilin-receptor sub-types, PlGF modulates a range of neural, glial and vascular cell responses that are distinct from VEGF-A. As PlGF expression is selectively associated with pathological angiogenesis and inflammation, its blockade does not affect the healthy vasculature. PlGF actions have been extensively described in tumor biology but more recently there has been accumulating preclinical evidence that indicates that this growth factor could have an important role in retinal diseases. High levels of PlGF have been found in aqueous humor, vitreous and/or retina of patients exhibiting retinopathies, especially those with diabetic retinopathy (DR) and neovascular age-related macular degeneration (nvAMD). Expression of this growth factor seems to correlate closely with many of the key pathogenic features of early and late retinopathy in preclinical models. For example, studies using genetic modification and/or pharmacological treatment to block PlGF in the laser-induced choroidal neovascularization (CNV) model, oxygen-induced retinopathy model, as well as various murine diabetic models, have shown that PlGF deletion or inhibition can reduce neovascularization, retinal leakage, inflammation and gliosis, without affecting vascular development or inducing neuronal degeneration. Moreover, an inhibitory effect of PlGF blockade on retinal scarring in the mouse CNV model has also been recently demonstrated and was found to be unique for PlGF inhibition, as compared to various VEGF inhibition strategies. Together, these preclinical results suggest that anti-PlGF therapy might have advantages over anti-VEGF treatment, and that it may have clinical applications as a standalone treatment or in combination with anti-VEGF. Additional clinical studies are clearly needed to further elucidate the role of PlGF and its potential as a therapeutic target in ocular diseases.


Assuntos
Neuropilinas/fisiologia , Fator de Crescimento Placentário/fisiologia , Doenças Retinianas/metabolismo , Animais , Neovascularização de Coroide/metabolismo , Retinopatia Diabética/metabolismo , Modelos Animais de Doenças , Humanos , Degeneração Macular/metabolismo , Fatores de Crescimento do Endotélio Vascular/fisiologia
10.
Environ Mol Mutagen ; 55(8): 662-72, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24889675

RESUMO

Tobacco smoke is a complex mixture of over 6,000 individual chemical constituents. Approximately 150 of these have been identified as 'tobacco smoke toxicants' due to their known toxicological effects. A number of these toxicants are present in the gaseous phase of tobacco smoke. This presents a technical challenge when assessing the toxicological effects of these chemicals in vitro. We have adapted a commercially available tobacco smoke exposure system to enable the assessment of the contribution of individual smoke toxicants to the overall toxicological effects of whole mainstream cigarette smoke (WS). Here we present a description of the exposure system and the methodology used. We use the example of a gaseous tobacco smoke toxicant, ethylene oxide (EtO), a Group 1 IARC carcinogen and known mutagen, to illustrate how this methodology can be applied to the assessment of genotoxicity of gaseous chemicals in the context of WS. In the present study we found that EtO was positive in Salmonella typhimurium strain YG1042, a strain that is sensitive to tobacco smoke. However, EtO did not increase the mutagenicity of the WS mixture when it was added at greatly higher concentrations than those found typically in WS. The findings presented here demonstrate the suitability of this exposure system for the assessment of the mutagenic potential of gases in vitro. Whilst we have focused on tobacco smoke toxicants, this system has broad application potential in studying the biological effects of exposure to a wide range of gaseous compounds that are present within complex aerosol mixtures.


Assuntos
Testes de Mutagenicidade/métodos , Nicotiana , Fumaça/análise , Poluição por Fumaça de Tabaco/efeitos adversos , Óxido de Etileno/toxicidade , Técnicas In Vitro , Testes de Mutagenicidade/instrumentação , Mutagênicos , Salmonella typhimurium/efeitos dos fármacos , Nicotiana/química
11.
J Cyst Fibros ; 13(1): 99-105, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23891279

RESUMO

BACKGROUND: Attitudes of Australian CF healthcare professionals toward population-based cystic fibrosis (CF) carrier screening were examined. METHOD: A purpose-designed questionnaire was distributed to 111 respiratory physicians and 30 CF clinic coordinators throughout Australia. RESULTS: Seventy-one questionnaires (52 physicians and 19 coordinators (46.8%, 63.3% respectively)) were returned. Forty respondents (56.3%) supported population-based carrier screening for CF. Support for screening was associated with rating the factors: carrier risk being 1 in 25 (OR 1.72 (1.12, 2.65)), reassurance when both partners test negative (OR 1.67 (1.12, 2.46)) and the daily treatment regimen for CF patients (OR 1.59 (1.05, 2.42)) as important. Opposition to screening was associated with identifying potential discrimination against carriers as a disadvantage (OR 0.3 (0.12, 0.88)), and limitations of predicting clinical outcomes as a barrier (OR 0.46 (0.25, 0.83)). CONCLUSIONS: There is moderate support for population-based carrier screening for CF by Australian CF healthcare professionals. Perceived barriers to implementation are surmountable.


Assuntos
Atitude do Pessoal de Saúde , Estudos Transversais , Fibrose Cística/genética , Triagem de Portadores Genéticos , Testes Genéticos , Pneumologia , Adulto , Austrália , Criança , Fibrose Cística/prevenção & controle , Feminino , Humanos , Modelos Logísticos , Masculino , Nova Zelândia , Enfermeiros Administradores/psicologia , Médicos/psicologia , Inquéritos e Questionários
12.
Science ; 342(6154): 1235587, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24092746

RESUMO

Interpreting variants, especially noncoding ones, in the increasing number of personal genomes is challenging. We used patterns of polymorphisms in functionally annotated regions in 1092 humans to identify deleterious variants; then we experimentally validated candidates. We analyzed both coding and noncoding regions, with the former corroborating the latter. We found regions particularly sensitive to mutations ("ultrasensitive") and variants that are disruptive because of mechanistic effects on transcription-factor binding (that is, "motif-breakers"). We also found variants in regions with higher network centrality tend to be deleterious. Insertions and deletions followed a similar pattern to single-nucleotide variants, with some notable exceptions (e.g., certain deletions and enhancers). On the basis of these patterns, we developed a computational tool (FunSeq), whose application to ~90 cancer genomes reveals nearly a hundred candidate noncoding drivers.


Assuntos
Variação Genética , Anotação de Sequência Molecular/métodos , Neoplasias/genética , Sítios de Ligação/genética , Genoma Humano , Genômica , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Mutação , Polimorfismo de Nucleotídeo Único , População/genética , RNA não Traduzido/genética , Seleção Genética
13.
Proc Natl Acad Sci U S A ; 110(39): 15668-73, 2013 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-24019476

RESUMO

SDS/PAGE is universally used in biochemistry, cell biology, and immunology to resolve minute protein amounts readily from tissue and cell extracts. Although molecular weights of water-soluble proteins are reliably determined from their SDS/PAGE mobility, most helical membrane proteins, which comprise 20-30% of the human genome and the majority of drug targets, migrate to positions that have for decades been unpredictably slower or faster than their actual formula weight, often confounding their identification. Using de novo designed transmembrane-mimetic polypeptides that match the composition of helical membrane-spanning sequences, we quantitate anomalous SDS/PAGE fractionation of helical membrane proteins by comparing the relative mobilities of these polypeptides with typical water-soluble reference proteins on Laemmli gels. We find that both the net charge and effective molecular size of the migrating particles of transmembrane-mimetic species exceed those of the corresponding reference proteins and that gel acrylamide concentration dictates the impact of these two factors on the direction and magnitude of anomalous migration. Algorithms we derived from these data compensate for this differential effect of acrylamide concentration on the SDS/PAGE mobility of a variety of natural membrane proteins. Our results provide a unique means to predict anomalous migration of membrane proteins, thereby facilitating straightforward determination of their molecular weights via SDS/PAGE.


Assuntos
Acrilamida/química , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas de Membrana/química , Humanos , Peso Molecular , Estrutura Secundária de Proteína , Padrões de Referência , Eletricidade Estática
14.
Hum Hered ; 73(1): 47-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22261837

RESUMO

AIMS: Next-generation sequencing has opened the possibility of large-scale sequence-based disease association studies. A major challenge in interpreting whole-exome data is predicting which of the discovered variants are deleterious or neutral. To address this question in silico, we have developed a score called Combined Annotation scoRing toOL (CAROL), which combines information from 2 bioinformatics tools: PolyPhen-2 and SIFT, in order to improve the prediction of the effect of non-synonymous coding variants. METHODS: We used a weighted Z method that combines the probabilistic scores of PolyPhen-2 and SIFT. We defined 2 dataset pairs to train and test CAROL using information from the dbSNP: 'HGMD-PUBLIC' and 1000 Genomes Project databases. The training pair comprises a total of 980 positive control (disease-causing) and 4,845 negative control (non-disease-causing) variants. The test pair consists of 1,959 positive and 9,691 negative controls. RESULTS: CAROL has higher predictive power and accuracy for the effect of non-synonymous variants than each individual annotation tool (PolyPhen-2 and SIFT) and benefits from higher coverage. CONCLUSION: The combination of annotation tools can help improve automated prediction of whole-genome/exome non-synonymous variant functional consequences.


Assuntos
Genômica/métodos , Anotação de Sequência Molecular/métodos , Software , Algoritmos , Humanos , Polimorfismo de Nucleotídeo Único , Curva ROC
15.
Vet Immunol Immunopathol ; 145(1-2): 214-22, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22197008

RESUMO

Neutrophil activation, whilst a key component of host defence, must be tightly regulated in order to avoid an inappropriate cellular response. Annexin-1, which is present in large amounts in neutrophils, and its N-terminal peptides, reduce neutrophil accumulation but annexin peptides have also been shown to exhibit neutrophil activating properties. We have recently shown annexin-1 to be present in equine neutrophils and demonstrated that the annexin-1-derived peptide, Ac2-26, can both reduce superoxide production by these cells in response to other stimuli and directly induce free radical production at a higher concentration. In the present study, we have further characterised the effects of Ac2-26 on equine neutrophil function. In addition, as anti-inflammatory glucocorticoids are known to up-regulate annexin-1, we have examined the effects of dexamethasone on annexin-1 expression in equine leukocytes. The effects of Ac2-26 alone and on agonist (CXCL8, leukotriene (LT)B(4) and PAF)-induced adherence and migration were examined by measuring adhesion of neutrophils to serum-coated plastic and by use of a ChemoTx migration assay. The role of formyl peptide receptors (FPRs) in mediating the effects of Ac2-26 was examined using the pan-FPR antagonist, BOC-2. Flow cytometry was used to measure the effects of dexamethasone on annexin-1 expression. Pre-incubation with Ac2-26 (10(-5)M) significantly inhibited neutrophil adhesion and migration in response to other agonists but when used alone could also induce these responses. The stimulatory and inhibitory effects of Ac2-26 were reduced by BOC-2, indicating a dependency on FPR activation. Dexamethasone increased the percentage of annexin-1 positive neutrophils and mononuclear cells by 1h post treatment (from 45±5% to 93±1% and 62±14% to 87±9% for neutrophils and monocytes, respectively) but by 4h there was no difference from control cells. No difference was seen between the percentages of annexin-1 positive cells pre- and post-treatment in animals that had undergone a dexamethasone suppression test. The attenuation of agonist-induced adherence and migration by Ac2-26 may play a part in regulating recruitment of equine neutrophils in inflammatory conditions of the horse. However, if high concentrations are produced in vivo following release of annexin-1 from activated cells, direct stimulatory effects may occur which could be either beneficial or detrimental. The therapeutic efficacy of anti-inflammatory steroids in the horse may be mediated in part by increasing annexin-1 expression although this effect appears to be short-lived.


Assuntos
Anexina A1/fisiologia , Ativação de Neutrófilo/fisiologia , Neutrófilos/fisiologia , Peptídeos/fisiologia , Animais , Anexina A1/biossíntese , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Dexametasona/farmacologia , Feminino , Citometria de Fluxo/veterinária , Cavalos , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Masculino , Neutrófilos/metabolismo
16.
J Mol Biol ; 407(1): 171-9, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21262233

RESUMO

δ-Helices are marginally hydrophobic α-helical segments in soluble proteins that exhibit certain sequence characteristics of transmembrane (TM) helices [Cunningham, F., Rath, A., Johnson, R. M. & Deber, C. M. (2009). Distinctions between hydrophobic helices in globular proteins and TM segments as factors in protein sorting. J. Biol. Chem., 284, 5395-402]. In order to better understand the difference between δ-helices and TM helices, we have studied the insertion of five TM-like δ-helices into dog pancreas microsomal membranes. Using model constructs in which an isolated δ-helix is engineered into a bona fide membrane protein, we find that, for two δ-helices originating from secreted proteins, at least three single-nucleotide mutations are necessary to obtain efficient membrane insertion, whereas one mutation is sufficient in a δ-helix from the cytosolic protein P450BM-3. We further find that only when the entire upstream region of the mutated δ-helix in the intact cytochrome P450BM-3 is deleted does a small fraction of the truncated protein insert into microsomes. Our results suggest that upstream portions of the polypeptide, as well as embedded charged residues, protect δ-helices in globular proteins from being recognized by the signal recognition particle-Sec61 endoplasmic-reticulum-targeting machinery and that δ-helices in secreted proteins are mutationally more distant from TM helices than δ-helices in cytosolic proteins.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , NADPH-Ferri-Hemoproteína Redutase/química , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/genética , Sistema Enzimático do Citocromo P-450/genética , Citoplasma/enzimologia , Cães , Interações Hidrofóbicas e Hidrofílicas , Bicamadas Lipídicas/metabolismo , Proteínas de Membrana/genética , Microssomos/enzimologia , Dados de Sequência Molecular , NADPH-Ferri-Hemoproteína Redutase/genética , Pâncreas/enzimologia , Estrutura Secundária de Proteína , Transporte Proteico , Canais de Translocação SEC
17.
Vet Immunol Immunopathol ; 139(2-4): 141-7, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21040981

RESUMO

The chemokine, CXCL8, is a potent chemoattractant but it has also been shown to attenuate the migratory response of human neutrophils to the bacterial peptide, FMLP; this could lead to retention of cells in infected tissue and, potentially, to enhanced clearance of bacteria. This study has examined the effect of CXCL8 on equine neutrophil migration and adherence in response to PAF and LTB(4), chemoattractants that may play a role in non-infectious inflammatory conditions of the horse associated with neutrophil recruitment to the target tissue. The effects of CXCL8 on PAF- and LTB(4)-induced responses were determined using a ChemoTx plate migration assay and by measuring adhesion to protein-coated plastic. The CXCR1/2 antagonist, SB225002, was used to investigate whether the observed effects were receptor mediated and the role of cAMP was examined by measuring intracellular cAMP following exposure to agonists alone and in combination and by establishing the effect of dibutyryl cAMP on neutrophil migration. CXCL8, LTB(4) and PAF each induced migration and adhesion. Exposure of neutrophils to a combination of CXCL8 and PAF reduced the magnitude of the responses to that of unstimulated cells. In contrast, although the effect was less than additive, the response to co-stimulation with CXCL8 and LTB(4) were not nearly as pronounced. CXCL8 acted in a receptor mediated manner, the attenuation of PAF-induced responses being reversed by SB225002 at a concentration that blocks CXCR2. CXCL8, PAF and LTB(4) alone increased intracellular cAMP. In co-incubation studies, combination of CXCL8 with PAF led to an additive increase in cAMP whereas no increase above that obtained in response to LTB(4) alone was seen. Dibutyryl cAMP significantly reduced neutrophil migration in response to either CXCL8 or PAF alone. These results demonstrate that CXCL8, in addition to being a potent chemoattractant and pro-adhesive molecule for equine neutrophils, is able to attenuate responses to PAF and, to a much lesser extent, LTB(4). This effect, which appears to be CXCR2-mediated and cAMP dependent, could lead in vivo to trapping of cells at sites of inflammation resulting potentially in either enhanced clearance of injurious stimuli or increased local tissue damage by activated cells.


Assuntos
Movimento Celular/efeitos dos fármacos , Interleucina-8/farmacologia , Leucotrieno B4/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/fisiologia , Fator de Ativação de Plaquetas/farmacologia , Animais , Adesão Celular , Células Cultivadas , Fatores Quimiotáticos/farmacologia , Colforsina/farmacologia , AMP Cíclico , Cavalos
18.
Hum Mutat ; 31(12): 1374-81, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20960468

RESUMO

The third Human Variome Project (HVP) Meeting "Integration and Implementation" was held under UNESCO Patronage in Paris, France, at the UNESCO Headquarters May 10-14, 2010. The major aims of the HVP are the collection, curation, and distribution of all human genetic variation affecting health. The HVP has drawn together disparate groups, by country, gene of interest, and expertise, who are working for the common good with the shared goal of pushing the boundaries of the human variome and collaborating to avoid unnecessary duplication. The meeting addressed the 12 key areas that form the current framework of HVP activities: Ethics; Nomenclature and Standards; Publication, Credit and Incentives; Data Collection from Clinics; Overall Data Integration and Access-Peripheral Systems/Software; Data Collection from Laboratories; Assessment of Pathogenicity; Country Specific Collection; Translation to Healthcare and Personalized Medicine; Data Transfer, Databasing, and Curation; Overall Data Integration and Access-Central Systems; and Funding Mechanisms and Sustainability. In addition, three societies that support the goals and the mission of HVP also held their own Workshops with the view to advance disease-specific variation data collection and utilization: the International Society for Gastrointestinal Hereditary Tumours, the Micronutrient Genomics Project, and the Neurogenetics Consortium.


Assuntos
Variação Genética/genética , Genoma Humano/genética , Mutação/genética , Coleta de Dados , Bases de Dados Genéticas/economia , Humanos , Motivação , Mutação/ética , Paris , Medicina de Precisão , Software , Terminologia como Assunto , Nações Unidas
19.
Vet Immunol Immunopathol ; 135(3-4): 226-33, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20079938

RESUMO

N-terminal peptides derived from the anti-inflammatory peptide, annexin-1, inhibit neutrophil function but can also induce pro-inflammatory effects. Although equine annexin-1 has been sequenced, its cellular expression and properties have not been reported. This study has examined whether annexin-1 is present in equine leucocytes and how the N-terminal peptide, Ac2-26, affects equine neutrophil superoxide production. Annexin-1 expression in equine neutrophils and mononuclear cells and the ability of Ac2-26 to activate neutrophil p42/44 MAPK were determined by immunoblotting. Equine neutrophil superoxide production was measured by the reduction of cytochrome (cyt) C following stimulation with Ac2-26 and the formyl peptide receptor (FPR) agonists, FMLP, WKYMVm and WKYMVM. Responses were examined in the presence of the pan-FPR antagonist, BOC-2, and the role of p42/44 MAPK in agonist-induced effects was determined using PD98059. The effect of Ac2-26 on superoxide production in response to serum-treated zymosan (STZ) was also investigated, and the roles of FPR and p42/44 MAPK ascertained. Annexin-1 was detected in both equine neutrophils and mononuclear cells using a polyclonal rabbit anti-human annexin-1 antibody. Ac2-26 (5x10(-5)M) induced superoxide production in cytochalasin B-primed (48+/-8 versus 21+/-9 (unstimulated cells) nmol cyt C/10(6) neutrophils) and un-primed cells (37+/-10 versus 11+/-5 nmol cyt C/10(6) neutrophils). FMLP and WKYMVm, but not WKYMVM, also caused superoxide production in primed neutrophils, suggesting the response was mediated by FPR receptor binding. This was supported by the marked inhibitory effect of BOC-2 on the responses to Ac2-26 and FMLP although, interestingly, the effects of WKYMVm were not significantly reduced (50+/-5 (WKYMVm) versus 45+/-5 (WKYMVm+BOC-2) nmol reduced cyt C/10(6) neutrophils). Inhibition of p42/44 MAPK activation with PD98059 significantly attenuated superoxide production in response to Ac2-26, FMLP and WKYMVm and Western blotting showed that Ac2-26 induced p42/44 MAPK activation. At a concentration which did not cause superoxide production, Ac2-26 (10(-5)M) significantly reduced the response to STZ (84+/-17% inhibition). This inhibitory effect was attenuated by both BOC-2 and PD98059. These results suggest that if activation of equine leucocytes in vivo leads to the release and subsequent cleavage of annexin-1, the N-terminal peptides formed could bind to neutrophil FPR and decrease free radical production in response to particulate stimuli. This could help to reduce local tissue damage but, as Ac2-26 can also stimulate superoxide production at higher concentrations in an FPR-dependent manner, the amount of free radical production may depend on the concentration of peptide present.


Assuntos
Anexina A1/sangue , Cavalos/sangue , Cavalos/imunologia , Leucócitos/metabolismo , Sequência de Aminoácidos , Animais , Anexina A1/química , Anexina A1/imunologia , Anexina A1/farmacologia , Flavonoides/farmacologia , Humanos , Técnicas In Vitro , Leucócitos/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Dados de Sequência Molecular , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Oligopeptídeos/farmacologia , Peptídeos/química , Peptídeos/imunologia , Peptídeos/farmacologia , Coelhos , Superóxidos/sangue
20.
Altern Lab Anim ; 37(6): 657-69, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20105001

RESUMO

Atherosclerosis is a disease process which develops at the arterial branches and curvatures of medium to large arteries. Local haemodynamic flow patterns in these vessels play an essential role in the formation of atherosclerotic lesions. To simulate pro-atherogenic blood flow patterns, we have developed a perfusion system with the ability to simulate in vivo patterns of blood flow in vitro. In this system, human umbilical vein endothelial cells were seeded in y-shaped microslides, in which they were exposed to a variety of flow patterns. Besides being able to reproduce the disturbed flow involved in the development of pro-atherogenic events within the arterial wall, the system also permitted the assessment of the pre-conditioning/priming effect of oscillatory flow on endothelial cells. The system was further capable of integrating multi-endpoint assays relevant to cardiovascular disease. We show that oscillatory flow primed endothelial cells, making them more sensitive to subsequent treatments. The treatment of oscillatory flow primed cells with TNFalpha resulted in the detection of enhanced levels of pro-inflammatory and chemoattractant factors such as IL-8 and MCP-1. These measurements were facilitated by the small volumes of medium circulating within the perfusion system. Oscillatory flow also altered the characteristics of monocyte adhesion to the endothelial layer. In summary, this system allows the monitoring of multiple endpoints and biomarkers, and provides an alternative to the use of in vivo and ex vivo models of cardiovascular disease.


Assuntos
Células Endoteliais/fisiologia , Aterosclerose/patologia , Aterosclerose/fisiopatologia , Adesão Celular/fisiologia , Técnicas de Cultura de Células/métodos , Linhagem Celular , Quimiocina CCL2/biossíntese , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Interleucina-8/metabolismo , Interleucina-8/farmacologia , Microscopia de Contraste de Fase , Monócitos/metabolismo , Perfusão/métodos , Fluxo Sanguíneo Regional , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
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