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1.
Clin Microbiol Infect ; 20(11): O960-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24712925

RESUMO

Chronic cavitary pulmonary aspergillosis (CCPA) is an uncommon but serious pulmonary disease of humans, with an annual mortality rate of 10-30%. It is caused by the fungus Aspergillus fumigatus. Patients are overtly immunocompetent; however, some immunogenetic defect is likely. To investigate this, we performed a genetic association study analysing biologically plausible candidate genes in 112 CCPA patients and 279 healthy controls, and investigated gene expression in monocyte-derived macrophages from patients and controls at baseline and during stimulation with A. fumigatus. Single-nucleotide polymorphisms (SNPs) associated with CCPA were found in TLR1, CLEC7A (dectin-1), PLAT (n=2), VEGFA, and DENND1B. Macrophages from CCPA patients showed low TLR3 and TLR10 expression and high TREM1 expression at baseline, as compared with macrophages from healthy subjects, with major expression differences being seen in most Toll-like receptors (TLRs) during 9 h of co-culture with A. fumigatus. The differences in baseline expression between the healthy and CCPA groups suggest roles for TLR3 and TLR10 in susceptibility to CCPA, and the association of SNPs in PLAT (n=2), VEGFA and DENND1B supports novel roles for plasminogen activation and angiogenesis and of these genes specifically in susceptibility to CCPA.


Assuntos
Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/biossíntese , Fatores de Troca do Nucleotídeo Guanina/biossíntese , Glicoproteínas de Membrana/biossíntese , Aspergilose Pulmonar/genética , Receptores Imunológicos/biossíntese , Ativador de Plasminogênio Tecidual/biossíntese , Receptor 10 Toll-Like/biossíntese , Receptor 3 Toll-Like/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese , Adulto , Idoso , Aspergillus fumigatus/isolamento & purificação , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/genética , Feminino , Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Macrófagos/imunologia , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Aspergilose Pulmonar/imunologia , Receptores Imunológicos/genética , Ativador de Plasminogênio Tecidual/genética , Receptor 10 Toll-Like/genética , Receptor 3 Toll-Like/genética , Receptor Gatilho 1 Expresso em Células Mieloides , Fator A de Crescimento do Endotélio Vascular/genética
2.
Clin Microbiol Infect ; 20(8): O480-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24274595

RESUMO

Chronic cavitary pulmonary aspergillosis (CCPA) is a progressive lung condition with a 10-30% annual mortality. Although overtly immunocompetent, some immunogenetic defect in patients is likely. To investigate a possible immunogenetic defect in CCPA, we analysed biologically plausible candidate genes in 112 CCPA patients and 279 healthy controls in a genetic association study of genes involved in the post-recognition immune response to Aspergillus fumigatus. We also compared gene expression in monocyte-derived macrophages from subjects with and without disease, both at baseline and during stimulation with A. fumigatus. Compared with macrophages from healthy subjects, CCPA macrophages showed unrestrained rises in IL1A, IL1B, IL6, IRAK2 and TRAF6 throughout the experiment, and a lack of expression of TGFB1 at 9 h. Single nucleotide polymorphisms (SNPs) associated with CCPA were found in IL1B (n = 2), IL1RN and IL15 (n = 3). Uncontrolled expression of IL1 and IL6 and continuing high levels of these cytokines may result in continuing cellular influx and pro-inflammatory responses, inhibiting disease resolution and contributing to disease progression in CCPA. The association of SNPs in IL1B, IL1RN and IL15 with CCPA supports a role for the IL1 pathway, as well as implicating the IL15 gene, in susceptibility to CCPA.


Assuntos
Aspergillus fumigatus/imunologia , Predisposição Genética para Doença , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-15/genética , Interleucina-1beta/genética , Aspergilose Pulmonar/imunologia , Adulto , Idoso , Feminino , Estudos de Associação Genética , Humanos , Proteína Antagonista do Receptor de Interleucina 1/imunologia , Interleucina-15/imunologia , Interleucina-1beta/imunologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
4.
Nat Nanotechnol ; 5(10): 727-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20890273

RESUMO

In spite of its excellent electronic properties, the use of graphene in field-effect transistors is not practical at room temperature without modification of its intrinsically semimetallic nature to introduce a bandgap. Quantum confinement effects can create a bandgap in graphene nanoribbons, but existing nanoribbon fabrication methods are slow and often produce disordered edges that compromise electronic properties. Here, we demonstrate the self-organized growth of graphene nanoribbons on a templated silicon carbide substrate prepared using scalable photolithography and microelectronics processing. Direct nanoribbon growth avoids the need for damaging post-processing. Raman spectroscopy, high-resolution transmission electron microscopy and electrostatic force microscopy confirm that nanoribbons as narrow as 40 nm can be grown at specified positions on the substrate. Our prototype graphene devices exhibit quantum confinement at low temperatures (4 K), and an on-off ratio of 10 and carrier mobilities up to 2,700 cm(2) V(-1) s(-1) at room temperature. We demonstrate the scalability of this approach by fabricating 10,000 top-gated graphene transistors on a 0.24-cm(2) SiC chip, which is the largest density of graphene devices reported to date.

5.
Eur Respir J ; 36(6): 1391-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20351026

RESUMO

In children, the ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) is reportedly constant or falls linearly with age, whereas the ratio of residual volume (RV) to total lung capacity (TLC) remains constant. This seems counter-intuitive given the changes in airway properties, body proportions, thoracic shape and respiratory muscle function that occur during growth. The age dependence of lung volumes, FEV1/FVC and RV/TLC were studied in children worldwide. Spirometric data were available for 22,412 healthy youths (51.4% male) aged 4-20 yrs from 15 centres, and RV and TLC data for 2,253 youths (56.7% male) from four centres; three sets included sitting height (SH). Data were fitted as a function of age, height and SH. In childhood, FVC outgrows TLC and FEV1, leading to falls in FEV1/FVC and RV/TLC; these trends are reversed in adolescence. Taking into account SH materially reduces differences in pulmonary function within and between ethnic groups. The highest FEV1/FVC ratios occur in those shortest for their age. When interpreting lung function test results, the changing pattern in FEV1/FVC and RV/TLC should be considered. Prediction equations for children and adolescents should take into account sex, height, age, ethnic group, and, ideally, also SH.


Assuntos
Desenvolvimento do Adolescente , Desenvolvimento Infantil , Volume Expiratório Forçado , Pulmão/crescimento & desenvolvimento , Pulmão/fisiologia , Capacidade Vital , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Adulto Jovem
6.
Stat Med ; 28(5): 880-98, 2009 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-19065626

RESUMO

Age-related reference ranges are useful for assessing growth in children. The LMS method is a popular technique for constructing growth charts that model the age-changing distribution of the measurement in terms of the median, coefficient of variation and skewness. Here the methodology is extended to references that depend on body size as well as age, by exploiting the flexibility of the generalised additive models for location, scale and shape (GAMLSS) technique. GAMLSS offers general linear predictors for each moment parameter and a choice of error distributions, which can handle kurtosis as well as skewness. A key question with such references is the nature of the age-size adjustment, additive or multiplicative, which is explored by comparing the identity link and log link for the median predictor.There are several measurements whose reference ranges depend on both body size and age. As an example, models are developed here for the first four moments of the lung function variables forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC) and FEV(1)/FVC in terms of height and age, in a data set of 3598 children and adults aged 4 to 80 years. The results show a strong multiplicative association between spirometry, height and age, with a large and nonlinear age effect across the age range. Variability also depends nonlinearly on age and to a lesser extent on height. FEV(1) and FVC are close to normally distributed, while FEV(1)/FVC is appreciably skew to the left. GAMLSS is a powerful technique for the construction of such references, which should be useful in clinical medicine.


Assuntos
Envelhecimento/fisiologia , Tamanho Corporal/fisiologia , Pulmão/fisiologia , Modelos Estatísticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Estatura/fisiologia , Criança , Pré-Escolar , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Caracteres Sexuais , Espirometria , Distribuições Estatísticas , Capacidade Vital/fisiologia , População Branca , Adulto Jovem
7.
Thorax ; 63(12): 1046-51, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18786983

RESUMO

AIM: The prevalence of airway obstruction varies widely with the definition used. OBJECTIVES: To study differences in the prevalence of airway obstruction when applying four international guidelines to three population samples using four regression equations. METHODS: We collected predicted values for forced expiratory volume in 1 s/forced vital capacity (FEV(1)/FVC) and its lower limit of normal (LLN) from the literature. FEV(1)/FVC from 40 646 adults (including 13 136 asymptomatic never smokers) aged 17-90+years were available from American, English and Dutch population based surveys. The prevalence of airway obstruction was determined by the LLN for FEV(1)/FVC, and by using the Global Initiative for Chronic Obstructive Lung Disease (GOLD), American Thoracic Society/European Respiratory Society (ATS/ERS) or British Thoracic Society (BTS) guidelines, initially in the healthy subgroup and then in the entire population. RESULTS: The LLN for FEV(1)/FVC varied between prediction equations (57 available for men and 55 for women), and demonstrated marked negative age dependency. Median age at which the LLN fell below 0.70 in healthy subjects was 42 and 48 years in men and women, respectively. When applying the reference equations (Health Survey for England 1995-1996, National Health and Nutrition Examination Survey (NHANES) III, European Community for Coal and Steel (ECCS)/ERS and a Dutch population study) to the selected population samples, the prevalence of airway obstruction in healthy never smokers aged over 60 years varied for each guideline: 17-45% of men and 7-26% of women for GOLD; 0-18% of men and 0-16% of women for ATS/ERS; and 0-9% of men and 0-11% of women for BTS. GOLD guidelines caused false positive rates of up to 60% when applied to entire populations. CONCLUSIONS: Airway obstruction should be defined by FEV(1)/FVC and FEV(1) being below the LLN using appropriate reference equations.


Assuntos
Doença Pulmonar Obstrutiva Crônica/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Erros de Diagnóstico , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto/normas , Valor Preditivo dos Testes , Valores de Referência , Capacidade Vital/fisiologia , Adulto Jovem
17.
Arch Dis Child ; 89(12): 1133-7, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15557051

RESUMO

In this article, the evidence base for botulinum-A treatment acquired in recent years is outlined, and the practicalities involved in providing this service are described. Botulinum-A is relatively new, and possible improvements for the future are considered.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Paralisia Cerebral/tratamento farmacológico , Fármacos Neuromusculares/administração & dosagem , Criança , Pré-Escolar , Previsões , Humanos , Injeções Intramusculares , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Dev Med Child Neurol ; 44(3): 177-80, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12005319

RESUMO

Fourteen children aged 4 to 14 years with hip subluxation due to cerebral palsy (CP) were considered for a trial in a lying hip abduction system (Jenx Dreama, Jenx Limited, Sheffield, UK). Baseline data were recorded for 6 months, then assessments of the system were made for one year at 6 and 12 months. Assessments consisted of hip radiographs in the standard position, a parental questionnaire, and a sleep chart, which was completed by parents every Friday night during the trial. Three children could not enter the trial because of general sleep problems, and three could not complete it because they were unable to sleep with the system. One further child withdrew from the study just before the end because of unacceptable deterioration for which surgery was needed. The remaining seven children completed the trial and there was an overall improvement in rate of hip migration percentage on the right from 7% per annum in the baseline period to 4% with the system (p<0.05). On the left, changes were -3% and 0% respectively (ns). Average sleep at night changed from 9 to 9.4 hours (ns) and wakenings/night from 1 to 1.3 (ns). On the parental questionnaire, there were significant improvements noted with the system in position for seating and sleeping, ease of hip abduction for washing, and with pain reduction. This pilot study supports the use of this type of lying system but further studies are needed to establish the acceptability and efficacy of these systems, particularly in children aged 2 to 5 years when irreversible bony deformities of the hip tend to occur.


Assuntos
Paralisia Cerebral/reabilitação , Equipamentos Médicos Duráveis , Luxação do Quadril/prevenção & controle , Articulação do Quadril , Adolescente , Paralisia Cerebral/complicações , Paralisia Cerebral/fisiopatologia , Criança , Pré-Escolar , Luxação do Quadril/etiologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/fisiopatologia , Humanos , Projetos Piloto , Estudos Prospectivos , Radiografia , Sono , Decúbito Dorsal , Resultado do Tratamento
19.
Occup Med ; 15(2): 411-20, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10769346

RESUMO

There are many potential problems with the use of serial peak expiratory flow (PEF) measurement to investigate potential occupational asthma. Among these are inaccurate and incomplete recording of results. However, PEF meters will continue to be used because of their relatively low cost and the availability of improved graphing methods and computer-assisted interpretation (OASYS-2). New technologies that automatically record PEF values and the time at which the maneuver was performed have improved the reliability of serial PEF measurements. Further, new hand-held spirometers not only record the test time but also the FEV&inf1; and FEV&inf6;, in addition to PEF. Automated assessment of maneuver quality with immediate feedback to the worker may improve test quality. The storage of raw volume-time or flow-volume curves, not yet widely available, can be used by reviewers to evaluate the quality of the maneuver on which PEF and FEV&inf1; values are based-further improving the reliability of serial measurements. Mechanical stimulators and testing waveforms are available to thoroughly test these new devices and insure that they meet the minimum ATS requirements for monitoring devices.


Assuntos
Asma/diagnóstico , Monitoramento Ambiental/métodos , Doenças Profissionais/diagnóstico , Espirometria/instrumentação , Asma/etiologia , Feminino , Humanos , Masculino , Pico do Fluxo Expiratório , Sensibilidade e Especificidade , Estatística como Assunto , Local de Trabalho
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