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1.
Br J Dermatol ; 181(1): 166-174, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30613954

RESUMO

BACKGROUND: High-mobility group box 1 (HMGB1) is a damage-associated molecular-pattern protein. Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) are serious, immune-mediated skin-blistering conditions. OBJECTIVES: To determine serum and/or blister-fluid total HMGB1 levels in SJS/TEN cohorts, and HMGB1 expression in formalin-fixed, paraffin-embedded (FFPE) SJS/TEN skin vs. healthy and maculopapular exanthema (MPE) skin. Methods Serum HMGB1 was quantified in Malawian nevirapine-induced hypersensitivity, Taiwanese SJS/TEN and Spanish SJS/TEN cohorts. FFPE skin (healthy skin, MPE, SJS/TEN) was stained and assessed for HMGB1 expression. RESULTS: Serum total HMGB1 was not significantly elevated in patients with nevirapine-induced SJS/TEN (3·98 ± 2·17 ng mL-1 ), MPE (3·92 ± 2·75 ng mL-1 ) or drug reaction with eosinophilia and systemic symptoms (4·73 ± 3·00 ng mL-1 ) vs. tolerant controls (2·97 ± 3·00 ng mL-1 ). HMGB1 was significantly elevated in Taiwanese patients with SJS/TEN, highest during the acute phase (32·6 ± 26·6 ng mL-1 ) vs. the maximal (19·7 ± 23·2 ng mL-1 ; P = 0·007) and recovery (24·6 ± 25·3 ng mL-1 ; P = 0·027) phases. In blister fluid from Spanish patients with SJS/TEN, HMGB1 (486·8 ± 687·9 ng mL-1 ) was significantly higher than in serum (8·8 ± 7·6 ng mL-1 ; P <0·001). Preblistered SJS/TEN skin showed decreased epidermal nuclear HMGB1 expression in upper epidermis vs. healthy or MPE skin but retained basal/suprabasal expression. CONCLUSIONS: Epidermal HMGB1 expression was decreased in SJS/TEN skin. Retained basal/suprabasal epidermal HMGB1 expression may exacerbate localized injury in SJS/TEN.


Assuntos
Vesícula/patologia , Epiderme/patologia , Proteína HMGB1/análise , Síndrome de Stevens-Johnson/diagnóstico , Adulto , Idoso , Biomarcadores/análise , Biomarcadores/metabolismo , Biópsia , Feminino , Proteína HMGB1/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Síndrome de Stevens-Johnson/sangue , Síndrome de Stevens-Johnson/patologia , Adulto Jovem
2.
Mucosal Immunol ; 11(1): 172-185, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28378806

RESUMO

Herpes simplex virus type 1 (HSV-1) infection of the cornea induces vascular endothelial growth factor A (VEGF-A)-dependent lymphangiogenesis that continues to develop well beyond the resolution of infection. Inflammatory leukocytes infiltrate the cornea and have been implicated to be essential for corneal neovascularization, an important clinically relevant manifestation of stromal keratitis. Here we report that cornea infiltrating leukocytes including neutrophils and T cells do not have a significant role in corneal neovascularization past virus clearance. Antibody-mediated depletion of these cells did not impact lymphatic or blood vessel genesis. Multiple pro-angiogenic factors including IL-6, angiopoietin-2, hepatocyte growth factor, fibroblast growth factor-2 (FGF-2), VEGF-A, and matrix metalloproteinase-9 were expressed within the cornea following virus clearance. A single bolus of dexamethasone at day 10 post infection (pi) resulted in suppression of blood vessel genesis and regression of lymphatic vessels at day 21 pi compared to control-treated mice. Whereas IL-6 neutralization had a modest impact on hemangiogenesis (days 14-21 pi) and lymphangiogenesis (day 21 pi) in a time-dependent fashion, neutralization of FGF-2 had a more pronounced effect on the suppression of neovascularization (blood and lymphatic vessels) in a time-dependent, leukocyte-independent manner. Furthermore, FGF-2 neutralization suppressed the expression of all pro-angiogenic factors measured and preserved visual acuity.


Assuntos
Córnea/irrigação sanguínea , Fator 2 de Crescimento de Fibroblastos/metabolismo , Herpes Simples/imunologia , Herpesvirus Humano 1/fisiologia , Ceratite Herpética/imunologia , Animais , Córnea/virologia , Neovascularização da Córnea , Dexametasona/uso terapêutico , Feminino , Herpes Simples/tratamento farmacológico , Interleucina-6/metabolismo , Ceratite Herpética/tratamento farmacológico , Linfangiogênese , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Linfócitos T/imunologia , Acuidade Visual
3.
Crit Rev Oncol Hematol ; 120: 127-140, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29198326

RESUMO

Chemotherapy-induced peripheral neuropathy (CIPN) can adversely affect completion of systemic anti-cancer treatment and cause long-term morbidity. Increasingly pharmacogenetic studies have been performed to explore susceptibility to this important adverse effect. A systematic review was conducted to identify pharmacogenetic studies, assess their quality and findings and undertake meta-analysis where possible. 93 studies were included. Notable methodological issues included lack of standardisation and detail in phenotype definition and acknowledgement of potential confounding factors. Insufficient data was presented in many studies meaning only a minority could be included in meta-analysis showing mainly non-significant effects. Nonetheless, SNPs in CYP2C8, CYP3A4, ARHGEF10, EPHA and TUBB2A genes (taxanes), FARS2, ACYP2 and TAC1 (oxaliplatin), and CEP75 and CYP3A5 (vincristine) are of potential interest. These require exploration in large cohort studies with robust methodology and well-defined phenotypes. Seeking standardisation of phenotype, collaboration and subsequently, individual-patient-data meta-analysis may facilitate identifying contributory SNPs which could be combined in a polygenic risk score to predict those most at risk of CIPN.


Assuntos
Antineoplásicos/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/genética , Antineoplásicos/uso terapêutico , Estudos de Coortes , Predisposição Genética para Doença , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Polimorfismo de Nucleotídeo Único
4.
Mucosal Immunol ; 9(4): 1065-75, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26627457

RESUMO

Type 1 interferons (IFNs; IFNα/ß) mediate immunological host resistance to numerous viral infections, including herpes simplex virus type 1 (HSV-1). The pathways responsible for IFNα/ß signaling during the innate immune response to acute HSV-1 infection in the cornea are incompletely understood. Using a murine ocular infection model, we hypothesized that the stimulator of IFN genes (STING) mediates resistance to HSV-1 infection at the ocular surface and preserves the structural integrity of this mucosal site. Viral pathogenesis, tissue pathology, and host immune responses during ocular HSV-1 infection were characterized by plaque assay, esthesiometry, pachymetry, immunohistochemistry, flow cytometry, and small interfering RNA transfection in wild-type C57BL/6 (WT), STING-deficient (STING(-/-)), and IFNα/ß receptor-deficient (CD118(-/-)) mice at days 3-5 postinfection. The presence of STING was critical for sustained control of HSV-1 replication in the corneal epithelium and resistance to viral neuroinvasion, but loss of STING had a negligible impact with respect to gross tissue pathology. Auxiliary STING-independent IFNα/ß signaling pathways were responsible for maintenance of corneal integrity. Lymphatic vessels, mast cells, and sensory innervation were compromised in CD118(-/-) mice concurrent with increased tissue edema. STING-dependent signaling led to the upregulation of tetherin, a viral restriction factor we identify is important in containing the spread of HSV-1 in vivo.


Assuntos
Antígenos CD/metabolismo , Córnea/imunologia , Herpes Simples/imunologia , Herpesvirus Humano 1/fisiologia , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Animais , Antígenos CD/genética , Células Cultivadas , Córnea/virologia , Modelos Animais de Doenças , Humanos , Imunidade Inata , Interferon Tipo I/metabolismo , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/genética , Glicoproteínas de Membrana/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Interferente Pequeno/genética , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de Sinais , Regulação para Cima , Replicação Viral
5.
Thorax ; 70(3): 288-90, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24664535

RESUMO

Although lung volume reduction surgery improves survival in selected patients with emphysema, there has been ongoing interest in developing and evaluating bronchoscopic approaches to try to reduce lung volumes with less morbidity and mortality. The placement of endobronchial valves is one such technique, and although some patients have had a significant improvement, responses have been inconsistent because collateral ventilation prevents lobar atelectasis. We describe the protocol of a trial (ISRCTN04761234) aimed to show that a responder phenotype, patients with heterogeneous emphysema and intact interlobar fissures on CT scanning, can be identified prospectively, leading to a consistent benefit in clinical practice.


Assuntos
Brônquios/cirurgia , Próteses e Implantes , Implantação de Prótese , Enfisema Pulmonar/cirurgia , Projetos de Pesquisa , Broncoscopia , Método Duplo-Cego , Volume Expiratório Forçado , Humanos , Medidas de Volume Pulmonar , Próteses e Implantes/efeitos adversos , Enfisema Pulmonar/fisiopatologia
6.
J R Army Med Corps ; 161(1): 9-13, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24109105

RESUMO

INTRODUCTION: Prevention against head wounds from explosively propelled fragments is currently the Mark 7 general service combat helmet, although only limited evidence exists to define the coverage required for the helmet to adequately protect against such a threat. The Royal Centre for Defence Medicine was tasked by Defence Equipment and Support to provide a framework for determining the optimum coverage of future combat helmets in order to inform the VIRTUS procurement programme. METHOD: A systematic review of the literature was undertaken to identify potential solutions to three components felt necessary to define the ideal helmet coverage required for protection against explosively propelled fragments. RESULTS: The brain and brainstem were identified as the structures requiring coverage by a helmet. No papers were identified that directly defined the margins of these structures to anatomical landmarks, nor how these could be related to helmet coverage. CONCLUSIONS: We recommend relating the margins of the brain to three identifiable anatomical landmarks (nasion, external auditory meatus and superior nuchal line), which can in turn be related to the coverage provided by the helmet. Early assessments using an anatomical mannequin indicate that the current helmet covers the majority of the brain and brainstem from projectiles with a horizontal trajectory but not from ones that originate from the ground. Protection from projectiles with ground-originating trajectories is reduced by helmets with increased stand-off from the skin. Future helmet coverage assessments should use a finite element numerical modelling approach with representative material properties assigned to intracranial anatomical structures to enable differences in projectile trajectory and helmet coverage to be objectively compared.


Assuntos
Traumatismos por Explosões/prevenção & controle , Traumatismos Cranianos Penetrantes/prevenção & controle , Dispositivos de Proteção da Cabeça , Traumatismos Ocupacionais/prevenção & controle , Desenho de Equipamento , Explosões , Humanos , Militares , Reino Unido
7.
J R Army Med Corps ; 159(4): 294-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24109096

RESUMO

INTRODUCTION: Indirect ballistic fractures occur when a projectile passes close to, but not contacting, the bone. The mechanism of how these fractures occur is not yet proven, but recently the acoustic shockwave has been excluded as a cause. The objective of this study is to determine whether the expanding temporary cavity, the collapse of this cavity or its oscillation causes these fractures. In addition, we describe the fracture morphology and biomechanical causes of this injury. METHOD: 40 fresh deer femora were strain gauged and embedded in ballistic gelatin before being shot with four different projectiles with varying distances off the bone. Pressure recordings, chronographs and radar allowed assessment of local pressures and energy transfer. High-speed video allowed the temporal relationship between the temporary cavity and fracture formation to be analysed, while sample dissection allowed the fracture morphology to be described. RESULTS: The fractures produced were consistently wedge-shaped and caused by the expansion of the temporary cavity, flexing the bone beyond its yield point, causing tension failure on the cortex opposite the expanding temporary cavity and a compression wedge on the side of the cavity. Local pressure was not predictive of fracture formation but the energy transfer to the gelatin block was predictive. CONCLUSIONS: Indirect fractures are caused by the expansion of the temporary cavity and relate to the proximity of this cavity to the bone. Fractures occur from flexion of the bone and classically display wedge-shaped fracture patterns with the apex of the wedge pointing away from the expanding cavity.


Assuntos
Fraturas do Fêmur , Ferimentos por Arma de Fogo , Transferência de Energia , Fêmur , Pressão
8.
Clin Pharmacol Ther ; 94(6): 695-701, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23942138

RESUMO

This study aimed to determine whether patients with statin-induced myopathy could be identified using the United Kingdom Clinical Practice Research Datalink, whether DNA could be obtained, and whether previously reported associations of statin myopathy with the SLCO1B1 c.521T>C and COQ2 rs4693075 polymorphisms could be replicated. Seventy-seven statin-induced myopathy patients (serum creatine phosphokinase (CPK) > 4× upper limit of normal (ULN)) and 372 statin-tolerant controls were identified and recruited. Multiple logistic regression analysis showed the SLCO1B1 c.521T>C single-nucleotide polymorphism to be a significant risk factor (P = 0.009), with an odds ratio (OR) per variant allele of 2.06 (1.32-3.15) for all myopathy and 4.09 (2.06-8.16) for severe myopathy (CPK > 10× ULN, and/or rhabdomyolysis; n = 23). COQ2 rs4693075 was not associated with myopathy. Meta-analysis showed an association between c.521C>T and simvastatin-induced myopathy, although power for other statins was limited. Our data replicate the association of SLCO1B1 variants with statin-induced myopathy. Furthermore, we demonstrate how electronic medical records provide a time- and cost-efficient means of recruiting patients with severe adverse drug reactions for pharmacogenetic studies.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Doenças Musculares/induzido quimicamente , Transportadores de Ânions Orgânicos/genética , Idoso , Estudos de Casos e Controles , Creatina Quinase/sangue , Bases de Dados Factuais , Feminino , Medicina Geral , Genótipo , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado , Masculino , Doenças Musculares/genética , Polimorfismo de Nucleotídeo Único , Ubiquinona/genética , Reino Unido
9.
Cancer Chemother Pharmacol ; 72(2): 359-68, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23756919

RESUMO

PURPOSE: The response of colorectal liver metastases to the cytotoxic agent irinotecan varies widely. Attempts to correlate tumour metabolism with response have been mixed. This study investigated the hepatic metabolism of irinotecan as a potential predictor of tumour response to irinotecan-eluting beads (DEBIRI). METHODS: Ten patients with colorectal liver metastases were treated with 200 mg irinotecan (as DEBIRI) as part of the PARAGON II study. Hepatic expression of key metabolising enzymes was measured using mass spectrometry-based proteomics. Serum drug concentrations and hepatic irinotecan metabolism were characterised and correlated with tumour response. RESULTS: Serum concentrations of irinotecan metabolites did not correlate with hepatic metabolism or pathological response. There was a strong correlation between hepatic CES-2 expression and activation of irinotecan (r (2) = 0.96, p < 0.001). Patients with a UGT1A1*28 6/7 SNP showed no difference in drug metabolism or pathological response. Hepatic CES-2 mediated activation of irinotecan clearly correlated with tumour replacement by fibrosis (r (2) = 0.54, p = 0.01). CONCLUSION: This study provides the first evidence that hepatic activation of irinotecan predicts tumour response. Delivery of liver-targeted irinotecan to normal liver tissue rather than tumour may be a more rational approach to maximise response.


Assuntos
Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/secundário , Neoplasias Hepáticas/patologia , Fígado/metabolismo , Antineoplásicos Fitogênicos/administração & dosagem , Biotransformação , Western Blotting , Camptotecina/administração & dosagem , Camptotecina/metabolismo , Camptotecina/uso terapêutico , Neoplasias Colorretais/cirurgia , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Sistemas de Liberação de Medicamentos , Genótipo , Glucuronosiltransferase/genética , Humanos , Irinotecano , Fígado/enzimologia , Espectrometria de Massas , Microssomos/metabolismo , Proteínas de Neoplasias/metabolismo , Estudos Prospectivos , Reprodutibilidade dos Testes
10.
Mucosal Immunol ; 6(1): 45-55, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22692455

RESUMO

Herpes simplex virus type 1 (HSV-1) is the leading cause of corneal blindness in the developed world due to reactivation of infectious virus and the subsequent immune response. The innate response that facilitates viral control in the cornea is currently unknown. In the present study using a mouse chimera model, we found that a bone marrow component is crucial in inhibiting viral replication and identified inflammatory monocytes (F4/80(+) Gr1(+)) as the responsible cell. CCL2 was critical for recruiting inflammatory monocytes, and a loss of this chemokine in CCL2(-/-) mice resulted in a loss of viral containment and inflammatory monocyte recruitment. To confirm these results, clodronate depletion of inflammatory monocytes resulted in elevated viral titers. Furthermore, siRNA targeting the innate sensor p204/IFI-16 resulted in a loss of CCL2 production. In conclusion, CCL2 expression driven by IFI-16 recognition of HSV-1 facilitates the recruitment of inflammatory monocytes into the cornea proper to control viral replication.


Assuntos
Quimiocina CCL2/biossíntese , Inflamação/imunologia , Inflamação/metabolismo , Interferon-alfa/metabolismo , Animais , Córnea/imunologia , Córnea/metabolismo , Córnea/virologia , Feminino , Herpesvirus Humano 1/imunologia , Inflamação/genética , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/genética , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/imunologia , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/metabolismo , Masculino , Camundongos , Camundongos Knockout , Modelos Imunológicos , Monócitos/imunologia , Monócitos/metabolismo , Óxido Nítrico/biossíntese , Replicação Viral
11.
BMC Bioinformatics ; 12: 136, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21548938

RESUMO

BACKGROUND: Probes on a microarray represent a frozen view of a genome and are quickly outdated when new sequencing studies extend our knowledge, resulting in significant measurement error when analyzing any microarray experiment. There are several bioinformatics approaches to improve probe assignments, but without in-house programming expertise, standardizing these custom array specifications as a usable file (e.g. as Affymetrix CDFs) is difficult, owing mostly to the complexity of the specification file format. However, without correctly standardized files there is a significant barrier for testing competing analysis approaches since this file is one of the required inputs for many commonly used algorithms. The need to test combinations of probe assignments and analysis algorithms led us to develop ArrayInitiative, a tool for creating and managing custom array specifications. RESULTS: ArrayInitiative is a standalone, cross-platform, rich client desktop application for creating correctly formatted, custom versions of manufacturer-provided (default) array specifications, requiring only minimal knowledge of the array specification rules and file formats. Users can import default array specifications, import probe sequences for a default array specification, design and import a custom array specification, export any array specification to multiple output formats, export the probe sequences for any array specification and browse high-level information about the microarray, such as version and number of probes. The initial release of ArrayInitiative supports the Affymetrix 3' IVT expression arrays we currently analyze, but as an open source application, we hope that others will contribute modules for other platforms. CONCLUSIONS: ArrayInitiative allows researchers to create new array specifications, in a standard format, based upon their own requirements. This makes it easier to test competing design and analysis strategies that depend on probe definitions. Since the custom array specifications are easily exported to the manufacturer's standard format, researchers can analyze these customized microarray experiments using established software tools, such as those available in Bioconductor.


Assuntos
Análise em Microsséries/métodos , Sondas de Oligonucleotídeos , Software , Adenocarcinoma/genética , Algoritmos , Humanos , Neoplasias Pulmonares/genética
12.
Pharmacogenomics J ; 9(5): 291-305, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19581920

RESUMO

Genetic polymorphisms in the one-carbon folate pathway have been widely studied in association with a number of conditions. Most of the research has focused on the 677C>T polymorphism in the coding region of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene. However, there are a total of 25 genes in this pathway coding for enzymes, transporters and receptors, which can be investigated using 267 tagging single nucleotide polymorphisms (SNPs); using SNP database (dbSNP), 38 non-synonymous SNPs with a minor allele frequency of >5% are present in these genes. Most of these variants have not been investigated in relation to disease or drug response phenotypes. In addition, their functional consequences are largely unknown. Prediction of the functional effect using six publicly available programs (PolyPhen, SIFT BLink, PMut, SNPs3D, I-Mutant2.0 and LS-SNP) was limited to functionally well-characterized SNPs such as MTHFR c.677C>T and c.1298A>C ranking low. Epigenetic modifications may also be important with some of these genes. In summary, to date, investigation of the one-carbon folate pathway genes has been limited. Future studies should aim for a more comprehensive assessment of this pathway, while further research is also required in determining the functional effects of these genetic variants.


Assuntos
Biologia Computacional , Epigênese Genética , Ácido Fólico/metabolismo , Ácido Fólico/uso terapêutico , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Animais , Bases de Dados Genéticas , Frequência do Gene , Predisposição Genética para Doença , Genética Populacional , Humanos , Hiper-Homocisteinemia/genética , Hiper-Homocisteinemia/metabolismo , Metabolômica , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Camundongos , Camundongos Transgênicos , Modelos Animais , Farmacogenética , Fenótipo
13.
Int J Low Extrem Wounds ; 7(4): 220-34, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18981057

RESUMO

Aims were to 1 characterize pretibial injuries and evaluate protection offered by garments/fabrics; and 2 develop a laboratory test to determine the potential protection provided by such fabrics. Most (>85%) of 75 patients treated for pretibial injury at Hutt Hospital, New Zealand sustained injury to one site and required surgery. Injuries were typically grade 3 or 4, 10-250 mm wide 30-350 mm long, and at the mid- to lower third of the tibia. The severity grade was lower when at least one fabric layer covered the site, slightly lower again with more than one layer, and when a knitted fabric/garment was worn, and a trouser type garment. Laboratory test methods and their application reflected these known variables. The force transmitted through multiple fabric layers was less then through one layer: thick pantyhouse and either denim or fabrics used in 'sweat pants' would minimize transmitted force and maximize impulse.


Assuntos
Traumatismos da Perna/prevenção & controle , Teste de Materiais/métodos , Roupa de Proteção , Pele/lesões , Têxteis/análise , Tíbia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Traumatismos da Perna/epidemiologia , Masculino , Nova Zelândia/epidemiologia , Distribuição Aleatória , Fatores de Risco , Estresse Mecânico
14.
Soc Reprod Fertil Suppl ; 63: 135-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17566268

RESUMO

Cyclic AMP (cAMP)-dependent protein kinase (PKA) is a signalling molecule involved in the regulation of many physiological functions including those of cilia and flagella. PKA localizes to specific cellular structures and organelles by binding to AKAP (A-kinase anchoring protein) molecules via interaction with the regulatory subunits (RI and RII) of PKA. AKAPs are capable of forming multi-protein complexes to coordinate the action of several signalling molecules all at a single location. AKAPs also bind to a group of four proteins that share the RII dimerization/docking (R2D2) domain. R2D2 proteins are expressed at high levels in both the testis and spermatozoa and mutants lacking R2D2 proteins exhibit abnormal sperm motility. Thus AKAPs and AKAP associated proteins appear to be key molecules in the biochemical machinery regulating the functions of flagella and cilia.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Transdução de Sinais/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Masculino , Proteínas de Membrana/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Cauda do Espermatozoide/metabolismo
15.
Biochem Biophys Res Commun ; 354(1): 259-64, 2007 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17210133

RESUMO

The anti-oxidant lipoic acid (LA) potently suppresses clinical and pathologic disease in the animal model of multiple sclerosis, experimental autoimmune encephalomyelitis, by inhibiting the migration of pathogenic T cells to the spinal cord. The mechanism by which this occurs is largely unknown. In this report we demonstrate that LA induces increases in cyclic AMP, a known immunosuppressant, in human T cells. The increase in cAMP is associated with increased adenylyl cyclase activity and is partially blocked by prostanoid receptor antagonists. We present evidence that LA also stimulates cAMP production in natural killer (NK) cells. This novel mechanism of action is highly relevant to the immunomodulatory effects of LA and provides further support for the study of LA as a therapeutic agent for multiple sclerosis and other autoimmune diseases.


Assuntos
AMP Cíclico/biossíntese , Células Matadoras Naturais/metabolismo , Linfócitos T/metabolismo , Ácido Tióctico/administração & dosagem , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Fatores Imunológicos/administração & dosagem , Células Matadoras Naturais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos
16.
Diabetologia ; 50(2): 439-42, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17171555

RESUMO

AIMS/HYPOTHESIS: Pancreatic polypeptide (PP) is produced by the F-cells of the pancreas, and its plasma concentration has been used as a marker of parasympathetic activity. Recent work in rodents suggests that there is both sympathetic and parasympathetic innervation of white adipose tissue and that parasympathetic activity is anabolic resulting in lipid accumulation. We have examined whether in humans increased PP levels are associated with increased intra-abdominal fat (IAF), and thereby insulin resistance. MATERIALS AND METHODS: We measured PP levels in 177 non-diabetic subjects (75 male/102 female; age 32-75 years) 3 min after an i.v. glucose bolus during a frequently sampled intravenous glucose tolerance test. IAF and s.c. fat (SCF) areas were measured by CT scan. The insulin sensitivity index (S (I)) was quantified using Bergman's minimal model. RESULTS: PP levels were higher in men than in women (96.2 +/- 72.2 vs 76.1 +/- 55.0 pg/ml, mean +/- SD, p = 0.037), as was IAF area (124.7 +/- 67.4 vs 83.0 +/- 57.7 cm(2), p < 0.001). While PP levels were significantly associated with IAF (r = 0.16, p = 0.031), WHR (r = 0.30, p < 0.001) and age (r = 0.37, p < 0.01), they were not associated with SCF (r = 0.02, p = 0.829). The association between PP and IAF was not independent of age and/or sex. S(I) was negatively associated with PP levels (r = -0.17, p = 0.026) and IAF area (r = -0.65, p < 0.001). The association between S(I) and PP disappeared after adjusting for IAF area, indicating that S(I) was not a major determinant of PP levels. CONCLUSIONS/INTERPRETATION: In humans, age and sex may modulate the association between plasma PP level and IAF area, suggesting that they may be determinants of parasympathetic activity and thus IAF accumulation.


Assuntos
Tecido Adiposo/anatomia & histologia , Polipeptídeo Pancreático/sangue , Abdome/anatomia & histologia , Adulto , Idoso , Glicemia/metabolismo , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Secreção de Insulina , Masculino , Pessoa de Meia-Idade
17.
J Bacteriol ; 188(23): 8231-43, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16997951

RESUMO

Legionella pneumophila, a causative agent of bacterial pneumonia, survives inside phagocytic cells by avoiding rapid targeting to the lysosome. This bacterium utilizes a type IVB secretion system, encoded by the dot/icm genes, to replicate inside host cells. DotL, a critical component of the Dot/Icm secretion apparatus, functions as the type IV coupling protein. In contrast to most dot/icm genes, which are dispensable for growth on bacteriological media, dotL is required for the viability of wild-type L. pneumophila. Previously we reported that DeltadotL lethality could be suppressed by inactivation of the Dot/Icm complex via mutations in other dot/icm genes. Here we report the isolation of non-dot/icm suppressors of this phenotype. These DeltadotL suppressors include insertions that disrupt the function of the L. pneumophila homologs of cpxR, djlA, lysS, and two novel open reading frames, lpg0742 and lpg1594, that we have named ldsA and ldsB for lethality of DeltadotL suppressor. In addition to suppressing DeltadotL lethality, inactivation of these genes in a wild-type strain background causes a range of defects in L. pneumophila virulence traits, including intracellular growth, implicating these factors in the proper function of the Dot/Icm complex. Consistent with previous data showing a role for the cpx system in regulating expression of several dot/icm genes, the cpxR insertion mutant produced decreased levels of three Dot/Icm proteins, DotA, IcmV, and IcmW. The remaining four suppressors did not affect the steady-state levels of any Dot/Icm protein and are likely to represent the first identified factors necessary for assembly and/or activation of the Dot/Icm secretion complex.


Assuntos
Proteínas de Bactérias/metabolismo , Genes Bacterianos , Legionella pneumophila/genética , Família Multigênica , Transdução de Sinais/genética , Supressão Genética , Animais , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Genes Supressores , Proteínas de Choque Térmico HSP40/genética , Humanos , Legionella pneumophila/crescimento & desenvolvimento , Doença dos Legionários/microbiologia , Macrófagos/microbiologia , Proteínas de Membrana/genética , Camundongos , Chaperonas Moleculares/genética , Fases de Leitura Aberta
18.
Mol Microbiol ; 61(3): 596-613, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16803597

RESUMO

Many bacterial pathogens require a functional type IV secretion system (T4SS) for virulence. Legionella pneumophila, the causative agent of Legionnaires' disease, employs the Dot/Icm T4SS to inject a large number of protein substrates into its host, thereby altering phagosome trafficking. The L. pneumophila T4SS substrate SdeA has been shown to require the accessory factor IcmS for its export. IcmS, defined as a type IV adaptor, exists as a heterodimer with IcmW and this complex functions in a manner similar to a type III secretion chaperone. Here we report an interaction between IcmS and the previously identified virulence factor LvgA. Similar to the icmS mutant, the lvgA mutant appears to assemble a fully functional Dot/Icm complex. Both LvgA and IcmS are small, acidic proteins localized to the cytoplasm and are not exported by the Dot/Icm system, suggesting they form a novel type IV adaptor complex. Inactivation of lvgA causes a minimal defect in growth in the human monocytic cell line U937 and the environmental host Acanthamoeba castellanii. However, the lvgA mutant was severely attenuated for intracellular growth of L. pneumophila in mouse macrophages, suggesting LvgA may be a critical factor that confers host specificity.


Assuntos
Proteínas de Bactérias/metabolismo , Legionella pneumophila/crescimento & desenvolvimento , Legionella pneumophila/metabolismo , Chaperonas Moleculares/metabolismo , Fatores de Virulência/metabolismo , Acanthamoeba castellanii/microbiologia , Animais , Proteínas de Bactérias/genética , Células Cultivadas/microbiologia , Citoplasma/metabolismo , Interações Hospedeiro-Parasita , Humanos , Legionella pneumophila/patogenicidade , Macrófagos/microbiologia , Camundongos , Chaperonas Moleculares/genética , Complexos Multiproteicos , Mutação , Fagocitose , Transporte Proteico , Fatores de Virulência/genética
19.
Cochrane Database Syst Rev ; (2): CD004843, 2006 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-16625614

RESUMO

BACKGROUND: The efficacy of music for the treatment of pain has not been established. OBJECTIVES: To evaluate the effect of music on acute, chronic or cancer pain intensity, pain relief, and analgesic requirements. SEARCH STRATEGY: We searched The Cochrane Library, MEDLINE, EMBASE, PsycINFO, LILACS and the references in retrieved manuscripts. There was no language restriction. SELECTION CRITERIA: We included randomized controlled trials that evaluated the effect of music on any type of pain in children or adults. We excluded trials that reported results of concurrent non-pharmacological therapies. DATA COLLECTION AND ANALYSIS: Data was extracted by two independent review authors. We calculated the mean difference in pain intensity levels, percentage of patients with at least 50% pain relief, and opioid requirements. We converted opioid consumption to morphine equivalents. To explore heterogeneity, studies that evaluated adults, children, acute, chronic, malignant, labor, procedural, or experimental pain were evaluated separately, as well as those studies in which patients chose the type of music. MAIN RESULTS: Fifty-one studies involving 1867 subjects exposed to music and 1796 controls met inclusion criteria. In the 31 studies evaluating mean pain intensity there was a considerable variation in the effect of music, indicating statistical heterogeneity ( I(2) = 85.3%). After grouping the studies according to the pain model, this heterogeneity remained, with the exception of the studies that evaluated acute postoperative pain. In this last group, patients exposed to music had pain intensity that was 0.5 units lower on a zero to ten scale than unexposed subjects (95% CI: -0.9 to -0.2). Studies that permitted patients to select the music did not reveal a benefit from music; the decline in pain intensity was 0.2 units, 95% CI (-0.7 to 0.2). Four studies reported the proportion of subjects with at least 50% pain relief; subjects exposed to music had a 70% higher likelihood of having pain relief than unexposed subjects (95% CI: 1.21 to 2.37). NNT = 5 (95% CI: 4 to 13). Three studies evaluated opioid requirements two hours after surgery: subjects exposed to music required 1.0 mg (18.4%) less morphine (95% CI: -2.0 to -0.2) than unexposed subjects. Five studies assessed requirements 24 hours after surgery: the music group required 5.7 mg (15.4%) less morphine than the unexposed group (95% CI: -8.8 to -2.6). Five studies evaluated requirements during painful procedures: the difference in requirements showed a trend towards favoring the music group (-0.7 mg, 95% CI: -1.8 to 0.4). AUTHORS' CONCLUSIONS: Listening to music reduces pain intensity levels and opioid requirements, but the magnitude of these benefits is small and, therefore, its clinical importance unclear.


Assuntos
Analgésicos Opioides/uso terapêutico , Musicoterapia , Manejo da Dor , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Thorax ; 61(8): 706-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16601085

RESUMO

BACKGROUND: Bronchiectasis is a suppurative airway disease characterised by persistent cough and sputum production associated with bronchial dilatation. A study was undertaken to determine whether cough sensitivity is increased in bronchiectatic patients. METHODS: Twenty two patients with bronchiectasis and 20 healthy non-smoking controls matched for age and sex were recruited into the study. Quality of life (Leicester Cough Questionnaire score), total cough symptom score, and extent of bronchiectasis on HRCT scans were recorded. Cough sensitivity was assessed using incremental inhalation of capsaicin concentrations; the concentration at which 5 or more coughs occurred (C5) was recorded. RESULTS: Patients with bronchiectasis had increased sensitivity to capsaicin compared with controls (mean (SE) log10 C5 1.22 (0.20) v 1.89 (0.21); p<0.03). Capsaicin sensitivity correlated positively with the Leicester Cough Questionnaire score (r = 0.64; p = 0.005) and inversely with the total cough symptom score (r = -0.58; p = 0.004), but not with the extent of the disease. It also correlated with forced expiratory volume in 1 second (FEV1) in litres (r = 0.58; p = 0.005) but not with FEV1 % predicted. Capsaicin sensitivity was not related to the presence of infected sputum or to corticosteroid or bronchodilator use. CONCLUSIONS: : Patients with bronchiectasis have a sensitive cough reflex which reflects the severity of cough symptoms. A measure of cough severity could be part of health assessment for patients with bronchiectasis.


Assuntos
Bronquiectasia/fisiopatologia , Testes de Provocação Brônquica/métodos , Broncoconstritores , Capsaicina , Tosse/fisiopatologia , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reflexo/fisiologia
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