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1.
Clin Exp Allergy ; 44(2): 250-60, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24147569

RESUMEN

BACKGROUND: Cross-sectional and longitudinal reports show that obese adults have more asthma than non-obese adults. A proposed mechanism is via effects of adipokines (leptin and adiponectin) on the immune system. OBJECTIVE: We wished to measure the associations of asthma and other atopic diseases with serum adipokine levels and to find whether the associations with asthma were strong enough to rule out the possibility that they are secondary to the association of fatness measures with asthma. METHODS: The Global Asthma and Allergy Network of Excellence (GA(2) LEN) clinical follow-up survey is a clinical survey, embedded in a larger multi-centre cross-sectional postal survey, involving, with a case/control design, enrichment of the sample with subjects with asthma and chronic rhinosinusitis (CRS). We recorded serum leptin or adiponectin in 845 men and 1110 women in 15 centres and also anthropometric measures of fatness including body mass index and waist/hip ratio, current asthma, and specific skin prick and IgE sensitisation. We used inverse sampling-probability-weighted rank and regression statistics to measure population associations of disease outcomes with adipokines in males and females, adjusting for confounders (area, age, smoking history, and number of elder siblings) and also mutually adjusting associations with adipokines and fatness measures. RESULTS: One thousand nine hundred and fifty-five subjects aged 16-77 years had information on leptin or adiponectin levels. Leptin and leptin/adiponectin ratio were positively associated with the level of asthma, especially in females (Somers' D of leptin by asthma score, 0.20; 95% CI, 0.08-0.30; P = 0.00079). These associations were attenuated after adjusting for confounders and became non-significant after additionally adjusting for fatness measures and multiple comparisons. CONCLUSIONS AND CLINICAL RELEVANCE: Asthma levels are positively associated with serum leptin. However, we cannot rule out the possibility that this association is secondary to associations of both with fatness measures.


Asunto(s)
Adiponectina/sangre , Asma/sangre , Leptina/sangre , Obesidad/sangre , Rinitis Alérgica Perenne/sangre , Adiponectina/inmunología , Adolescente , Adulto , Anciano , Asma/complicaciones , Asma/inmunología , Asma/patología , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Leptina/inmunología , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/inmunología , Obesidad/patología , Rinitis Alérgica Perenne/complicaciones , Rinitis Alérgica Perenne/inmunología , Rinitis Alérgica Perenne/patología , Factores Sexuales , Pruebas Cutáneas
2.
Allergy ; 69(5): 643-51, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24654915

RESUMEN

BACKGROUND: Geographical variation in the prevalence of sensitization to aeroallergens may reflect differences in exposure to risk factors such as having older siblings, being raised on a farm or other unidentified exposures. OBJECTIVE: We wanted to measure geographical variation in skin prick test positivity and assess whether it was explained by differences in family size and/or farm exposure. We also compared prevalence in younger and older subjects. METHODS: Within the Global Allergy and Asthma European Network (GA(2) LEN) survey, we measured the prevalence of skin prick positivity to a panel of allergens, and geometric mean serum total immunoglobulin E (IgE), in 3451 participants aged 18-75 years in 13 areas of Europe. Estimated prevalence was standardized to account for study design. We compared prevalence estimates in younger and older subjects and further adjusted for age, gender, smoking history, farm exposure, number of older siblings and body mass index (BMI). RESULTS: Skin prick test positivity to any one of the measured allergens varied within Europe from 31.4% to 52.9%. Prevalence of sensitization to single allergens also varied. Variation in serum total IgE was less marked. Younger participants had higher skin prick sensitivity prevalence, but not total IgE, than older participants. Geographical variation remained even after adjustment for confounders. CONCLUSION: Geographical variation in the prevalence of skin prick test positivity in Europe is unlikely to be explained by geographical variation in gender, age, smoking history, farm exposure, family size and BMI. Higher prevalence in younger, compared to older, adults may reflect cohort-associated increases in sensitization or the influence of ageing on immune or tissue responses.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Alérgenos/inmunología , Hipersensibilidad/epidemiología , Hipersensibilidad/inmunología , Adolescente , Adulto , Anciano , Alérgenos/clasificación , Animales , Femenino , Salud Global/estadística & datos numéricos , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Prevalencia , Vigilancia en Salud Pública , Factores de Riesgo , Adulto Joven
3.
Allergy ; 68(10): 1289-97, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24117882

RESUMEN

BACKGROUND: Specific IgE to Staphylococcus aureus enterotoxins (SE-IgE) has been associated with asthma. In the general population, we aimed to determine the prevalence of and risk factors for serum SE-IgE and to examine the association with asthma. METHODS: A postal questionnaire was sent to a random sample of adults in 19 centers across Europe. A random sample of respondents was invited for clinical examination upon which they answered a questionnaire, underwent skin prick tests (SPTs) for common aeroallergens, and provided blood for measurement of total IgE and SE-IgE. Risks were analyzed within centers using weighted logistic regression, and overall estimates calculated using fixed-effects meta-analysis. RESULTS: 2908 subjects were included in this analysis. Prevalence of positive SE-IgE was 29.3%; no significant geographic variation was observed. In contrast to positive skin prick tests, SE-IgE was more common in smokers (<15 pack-year: OR 1.11, P = 0.079, ≥15 pack-year: OR 1.70, P < 0.001), and prevalence did not decrease in older age-groups or in those with many siblings. Total IgE concentrations were higher in those with positive SE-IgE than in those with positive SPT. SE-IgE was associated with asthma (OR 2.10, 95% confidence interval [1.60-2.76], P = 0.001) in a concentration-dependent manner. This effect was independent of SPT result and homogeneous across all centers. CONCLUSIONS: We report for the first time that SE-IgE is common in the general population throughout Europe and that its risk factors differ from those of IgE against aeroallergens. This is the first study to show that SE-IgE is significantly and independently associated with asthma in the general population.


Asunto(s)
Especificidad de Anticuerpos/inmunología , Asma/epidemiología , Asma/inmunología , Enterotoxinas/inmunología , Inmunoglobulina E/inmunología , Vigilancia de la Población , Staphylococcus aureus/inmunología , Adolescente , Adulto , Anciano , Alérgenos/inmunología , Asma/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Pruebas Cutáneas , Encuestas y Cuestionarios , Adulto Joven
4.
Appetite ; 71: 22-31, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23891557

RESUMEN

Salt reduction is important for reducing hypertension and the risk of cardiovascular events, nevertheless worldwide salt intakes are above recommendations. Consequently strategies to reduce intake are required, however these require an understanding of salt intake behaviours to be effective. As limited information is available on this, an international study was conducted to derive knowledge on salt intake and associated behaviours in the general population. An online cohort was recruited consisting of a representative sample from Germany, Austria, United States of America, Hungary, India, China, South Africa, and Brazil (n=6987; aged 18-65 years; age and gender stratified). Participants completed a comprehensive web-based questionnaire on salt intake and associated behaviours. While salt reduction was seen to be healthy and important, over one third of participants were not interested in salt reduction and the majority were unaware of recommendations. Salt intake was largely underestimated and people were unaware of the main dietary sources of salt. Participants saw themselves as mainly responsible for their salt intake, but also acknowledged the roles of others. Additionally, they wanted to learn more about why salt was bad for health and what the main sources in the diet were. As such, strategies to reduce salt intake must raise interest in engaging in salt reduction through improving understanding of intake levels and dietary sources of salt. Moreover, while some aspects of salt reduction can be globally implemented, local tailoring is required to match level of interest in salt reduction. These findings provide unique insights into issues surrounding salt reduction and should be used to develop effective salt reduction strategies and/or policies.


Asunto(s)
Dieta , Conducta Alimentaria , Cloruro de Sodio Dietético/administración & dosificación , Adolescente , Adulto , Anciano , Conducta de Elección , Estudios de Cohortes , Femenino , Preferencias Alimentarias , Promoción de la Salud , Humanos , Hipertensión/prevención & control , Internacionalidad , Modelos Lineales , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto Joven
5.
Allergy ; 67(1): 91-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22050239

RESUMEN

BACKGROUND: The prevalence of asthma and its association with chronic rhinosinusitis (CRS) have not been widely studied in population-based epidemiological surveys. METHODS: The Global Allergy and Asthma Network of Excellence (GA(2) LEN) conducted a postal questionnaire in representative samples of adults living in Europe to assess the presence of asthma and CRS defined by the European Position Paper on Rhinosinusitis and Nasal Polyps. The prevalence of self-reported current asthma by age group was determined. The association of asthma with CRS in each participating centre was assessed using logistic regression analyses, controlling for age, sex and smoking, and the effect estimates were combined using standard methods of meta-analysis. RESULTS: Over 52,000 adults aged 18-75 years and living in 19 centres in 12 countries took part. In most centres, and overall, the reported prevalence of asthma was lower in older adults (adjusted OR for 65-74 years compared with 15-24 years: 0.72; 95% CI: 0.63-0.81). In all centres, there was a strong association of asthma with CRS (adjusted OR: 3.47; 95% CI: 3.20-3.76) at all ages. The association with asthma was stronger in those reporting both CRS and allergic rhinitis (adjusted OR: 11.85; 95% CI: 10.57-13.17). CRS in the absence of nasal allergies was positively associated with late-onset asthma. CONCLUSION: Geographical variation in the prevalence of self-reported asthma was observed across Europe, but overall, self-reported asthma was more common in young adults, women and smokers. In all age groups, men and women, and irrespective of smoking behaviour, asthma was also associated with CRS.


Asunto(s)
Asma/complicaciones , Asma/epidemiología , Rinitis/complicaciones , Rinitis/epidemiología , Sinusitis/complicaciones , Sinusitis/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Recolección de Datos , Europa (Continente)/epidemiología , Femenino , Humanos , Hipersensibilidad/complicaciones , Masculino , Persona de Mediana Edad , Pólipos Nasales/complicaciones , Prevalencia , Adulto Joven
6.
Allergy ; 66(4): 556-61, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21083566

RESUMEN

BACKGROUND: The European Position Paper on Rhinosinusitis and Nasal Polyps (EP3OS) incorporates symptomatic, endoscopic, and radiologic criteria in the clinical diagnosis of chronic rhinosinusitis (CRS), while in epidemiological studies, the definition is based on symptoms only. We aimed to assess the reliability and validity of a symptom-based definition of CRS using data from the GA(2) LEN European survey. METHODS: On two separate occasions, 1700 subjects from 11 centers provided information on symptoms of CRS, allergic rhinitis, and asthma. CRS was defined by the epidemiological EP3OS symptom criteria. The difference in prevalence of CRS between two study points, the standardized absolute repeatability, and the chance-corrected repeatability (kappa) were determined. In two centers, 342 participants underwent nasal endoscopy. The association of symptom-based CRS with endoscopy and self-reported doctor-diagnosed CRS was assessed. RESULTS: There was a decrease in prevalence of CRS between the two study phases, and this was consistent across all centers (-3.0%, 95% CI: -5.0 to -1.0%, I(2) = 0). There was fair to moderate agreement between the two occasions (kappa = 39.6). Symptom-based CRS was significantly associated with positive endoscopy in nonallergic subjects, and with self-reported doctor-diagnosed CRS in all subjects, irrespective of the presence of allergic rhinitis. CONCLUSION: Our findings suggest that a symptom-based definition of CRS, according to the epidemiological part of the EP3OS criteria, has a moderate reliability over time, is stable between study centers, is not influenced by the presence of allergic rhinitis, and is suitable for the assessment of geographic variation in prevalence of CRS.


Asunto(s)
Endoscopía , Rinitis Alérgica Perenne/diagnóstico , Rinitis Alérgica Perenne/epidemiología , Sinusitis/diagnóstico , Sinusitis/epidemiología , Adolescente , Adulto , Anciano , Enfermedad Crónica , Estudios Transversales , Humanos , Persona de Mediana Edad , Prevalencia , Adulto Joven
7.
Allergy ; 66(9): 1216-23, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21605125

RESUMEN

BACKGROUND: Chronic rhinosinusitis (CRS) is a common health problem, with significant medical costs and impact on general health. Even so, prevalence figures for Europe are unavailable. In this study, conducted by the GA²LEN network of excellence, the European Position Paper on Rhinosinusitis and nasal Polyps (EP³OS) diagnostic criteria are applied to estimate variation in the prevalence of Chronic rhinosinusitis (CRS) for Europe. METHOD: A postal questionnaire was sent to a random sample of adults aged 15-75 years in 19 centres in Europe. Participants reported symptoms of CRS, and doctor diagnosed CRS, allergic rhinitis, age, gender and smoking history. Definition of CRS was based on the EP³OS diagnostic criteria: the presence of more than two of the symptoms: (i) nasal blockage, (ii) nasal discharge, (iii) facial pain/pressure or (iv) reduction in sense of smell, for >12 weeks in the past year--with at least one symptom being nasal blockage or discharge. RESULTS: Information was obtained from 57,128 responders living in 19 centres in 12 countries. The overall prevalence of CRS by EP³OS criteria was 10.9% (range 6.9-27.1). CRS was more common in smokers than in nonsmokers (OR 1.7: 95% CI 1.6-1.9). The prevalence of self-reported physician-diagnosed CRS within centres was highly correlated with the prevalence of EP³OS-diagnosed CRS. CONCLUSION: This is the first European international multicentre prevalence study of CRS. In this multicentre survey of adults in Europe, about one in ten participants had CRS with marked geographical variation. Smoking was associated with having CRS in all parts of Europe.


Asunto(s)
Rinitis/epidemiología , Sinusitis/epidemiología , Adolescente , Adulto , Anciano , Enfermedad Crónica , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pólipos Nasales/diagnóstico , Prevalencia , Rinitis/diagnóstico , Factores de Riesgo , Sinusitis/diagnóstico , Encuestas y Cuestionarios , Adulto Joven
8.
Thorax ; 65(10): 897-902, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20805158

RESUMEN

BACKGROUND: Maternal smoking during pregnancy has detrimental effects on the respiratory health of infants and children. Polymorphisms of antioxidant genes including glutathione-S-transferases (GSTs) have been proposed as candidates for asthma and reduced lung function in children. METHODS: Women enrolled in the Avon Longitudinal Study of Parents and Children reported smoking habits during pregnancy. Asthma status in their children was established at age 7.5 years from parental reports and lung function was measured by spirometry at age 8.5 years. Maternal and child DNA were genotyped for deletions of GSTM1 and GSTT1 and functional polymorphisms of GSTP1 and Nrf2 genes. Associations of prenatal tobacco smoke exposure with asthma and lung function in children were stratified by maternal genotype. RESULTS: In 6606 children, maternal smoking during pregnancy was negatively associated with maximal mid expiratory flow (FEF(25-75)) (-0.05 SD units, 95% CI -0.07 to -0.03, p<0.001). There was little evidence for interactions between maternal smoking and any maternal genotype considered on children's asthma or lung function. Maternal smoking was associated with reduced childhood FEF(25-75) only in mother-child pairs (n=1227) with both copies of GSTM1 deleted (-0.08 SD units, 95% CI -0.14 to -0.02, p=0.01) or (n=2313) at least one copy of GSTT1 present (-0.05 SD units, 95% CI -0.09 to 0, p=0.03). CONCLUSION: This study confirms a detrimental effect of intrauterine tobacco smoke exposure on childhood lung function but no strong evidence of modification by maternal genotype for important antioxidant genes. Adverse effects of fetal exposure to tobacco smoke on the respiratory health of children may be mediated by pathways other than oxidative stress.


Asunto(s)
Asma/embriología , Glutatión Transferasa/genética , Factor 2 Relacionado con NF-E2/genética , Efectos Tardíos de la Exposición Prenatal , Contaminación por Humo de Tabaco/efectos adversos , Asma/epidemiología , Asma/genética , Asma/fisiopatología , Niño , Inglaterra/epidemiología , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Flujo Espiratorio Medio Máximo , Polimorfismo Genético , Embarazo , Factores de Riesgo , Fumar/epidemiología , Fumar/genética
9.
Thorax ; 64(5): 411-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19213776

RESUMEN

BACKGROUND: Studies of the relation between maternal diet in pregnancy and respiratory and atopic outcomes in the offspring have focused on the effects of individual nutrients and foods rather than dietary patterns. A study was undertaken to determine whether dietary patterns in pregnancy are related to childhood asthma and related outcomes. METHODS: In a population-based birth cohort, the Avon Longitudinal Study of Parents and Children (ALSPAC), dietary patterns in pregnancy previously identified using principal components analysis ("health conscious", "traditional", "processed", "vegetarian" and "confectionery") were related to early wheezing phenotypes and eczema; wheezing, hay fever, eczema, doctor-diagnosed asthma, atopy and total IgE at 7 years; lung function and bronchial responsiveness at 8-9 years. In regression models, confounders were controlled for using propensity scores. RESULTS: Univariately, the "health conscious" pattern was positively associated with eczema, total IgE, forced expiratory volume in 1 s and forced expiratory flow and negatively associated with early wheezing and asthma (unadjusted odds ratios per standard deviation increase in pattern score for early persistent wheeze and asthma: 0.78 (95% CI 0.70 to 0.87), p = 7.3x10(-6), N = 8886 and 0.90 (95% CI 0.84 to 0.97), p = 0.007, N = 7625, respectively). The "processed" pattern was positively associated with early wheezing and negatively associated with atopy and forced vital capacity. On controlling for confounders, the effects were substantially attenuated and became non-significant (adjusted odds ratios for the associations of the "health conscious" pattern with early persistent wheeze and asthma: 1.00 (0.86 to 1.16), p = 0.99 and 0.95 (0.86 to 1.04), p = 0.27, respectively). CONCLUSIONS: In this cohort, dietary patterns in pregnancy did not predict asthma and related outcomes in the offspring after controlling for confounders.


Asunto(s)
Asma/epidemiología , Dieta/efectos adversos , Eccema/epidemiología , Efectos Tardíos de la Exposición Prenatal/epidemiología , Fenómenos Fisiologicos de la Nutrición Prenatal/fisiología , Trastornos Respiratorios/epidemiología , Niño , Preescolar , Estudios de Cohortes , Eccema/fisiopatología , Inglaterra/epidemiología , Conducta Alimentaria , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Lactante , Estudios Longitudinales , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Prevalencia , Trastornos Respiratorios/fisiopatología , Ruidos Respiratorios/fisiopatología , Rinitis Alérgica Estacional/epidemiología , Capacidad Vital/fisiología
10.
Mutagenesis ; 24(1): 25-33, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18776173

RESUMEN

Genomic instability is considered to be an important component in carcinogenesis. It can be caused by low-dose exposure to agents, which appear to act through induction of stress-response pathways related to oxidative stress. These agents have been studied mostly in the radiation field but evidence is accumulating that chemicals, especially heavy metals such as Cr (VI), can also act in the same manner. Previous work showed that metal ions could initiate long-term genomic instability in human primary fibroblasts and this phenomenon was regulated by telomerase. The aim of this study was to examine the difference in clonogenic survival and cytogenetic damage after exposure to Cr (VI) and radiation both singly and in combination in normal human fibroblasts (hTERT- cells) and engineered human fibroblasts, infected with a retrovirus carrying a cDNA encoding hTERT, which rendered these cells telomerase positive and replicatively immortal (hTERT+ cells). Cr (VI) induced genomic instability in hTERT- cells but not in hTERT+ cells, whereas radiation induced genomic instability in hTERT+ cells and to a lesser extent in hTERT- cells. Combined exposure caused genomic instability in both types of cells. However, this genomic instability was more pronounced in hTERT- cells after radiation followed by Cr (VI) and more pronounced in hTERT+ cells after Cr (VI) followed by radiation. Moreover, the biological effects provoked by combined exposure of Cr (VI) and radiation also led to a synergistic action in both types of cells, compared to either Cr (VI) treatment only or radiation exposure only. This study suggests that telomerase can prevent genomic instability caused by Cr (VI), but not by radiation. Furthermore, genomic instability may be prevented by telomerase when cells are exposed to radiation and then Cr (VI) but not after exposure to Cr (VI) and then radiation.


Asunto(s)
Cromo/toxicidad , Rayos gamma , Inestabilidad Genómica , Telomerasa/metabolismo , Línea Celular , Supervivencia Celular , ADN/efectos de los fármacos , ADN/efectos de la radiación , Inestabilidad Genómica/genética , Humanos , Dicromato de Potasio/toxicidad , Telomerasa/genética
11.
Allergy ; 63(5): 542-6, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18394128

RESUMEN

BACKGROUND: Reports on air pollution and asthma exacerbations have been inconsistent, although effects of airborne allergen can be spectacular. With no generalized test for allergen in air, it is not known how far allergen is responsible for nonepidemic exacerbations of the disease. METHODS: Two hundred and ninety-seven patients using bronchodilators aged 18-64 years attending a London practice provided serum samples and were asked to report any acute respiratory events over the coming months. Small particles with a mean aerodynamic diameter <10 microm (PM(10)) were collected using a high volume sampler on the roof of the practice. The ability of airborne particles to bind IgE from the patients was compared for particles sampled on the weekend before their reported exacerbation with particles sampled on the weekend 2 weeks before or after. RESULTS: Exacerbations were associated with a 25% increase in IgE binding to particles collected on the previous weekend compared with the control weekends (95% confidence interval: 10-43%; P = 0.00089). This increase was not higher in patients with positive skin tests or in those sensitized to grass or tree pollens. CONCLUSIONS: Airborne allergen is an important cause of exacerbations even in those with 'intrinsic' asthma. It is important to identify the allergens responsible, as some of these may be controllable. Interpretation of associations of asthma exacerbations with other air pollutants is difficult in the light of these findings.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Alérgenos/efectos adversos , Asma/fisiopatología , Hipersensibilidad Inmediata/fisiopatología , Material Particulado/efectos adversos , Trastornos Respiratorios/fisiopatología , Adolescente , Adulto , Contaminantes Atmosféricos/inmunología , Contaminantes Atmosféricos/metabolismo , Contaminación del Aire , Alérgenos/inmunología , Alérgenos/metabolismo , Asma/inmunología , Femenino , Humanos , Hipersensibilidad Inmediata/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina E/metabolismo , Masculino , Persona de Mediana Edad , Material Particulado/inmunología , Material Particulado/metabolismo , Trastornos Respiratorios/inmunología , Pruebas Cutáneas
12.
Mutat Res ; 643(1-2): 11-9, 2008 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-18614183

RESUMEN

Particles of surgical cobalt chrome alloy are cytotoxic and genotoxic to human fibroblasts in vitro. In vivo orthopaedic patients are exposed to cobalt chrome particles as a result of wear of a joint replacement. Many of the wear debris particles that are produced are phagocytosed by macrophages that accumulate at the site of the worn implant and are disseminated to local and distant lymph nodes the liver and the spleen. In this study we have tested whether this process of phagocytosis could have altered the cytotoxic and genotoxic properties of the cobalt chrome particles. Quartz particles have been investigated as a control. Micron-sized particles of cobalt chrome alloy were internalised by either white cells of peripheral blood or by THP-1 monocytes for 1 week and 1 day, respectively. The particles were then extracted and presented at different doses to fibroblasts for 1 day. There was a reduction of the cytotoxicity and genotoxicity of the cobalt chrome particles after phagocytosis by white cells or THP-1 cells. Cobalt chrome particles that were internalised by fibroblasts also showed a reduction of their cytotoxicity but not their genotoxicity. In contrast the cytotoxicity and genotoxicity of quartz particles was increased after internalisation by THP-1 cells. The surface morphology of the cobalt chrome particles but not the quartz particles was changed after phagocytosis by THP-1 cells. This study suggests that the genotoxic and cytotoxic properties of particles that fall within the size range for phagocytosis may be highly complex in vivo and depend on the combination of material type and previous phagocytosis. These results may have relevance for particle exposure from orthopaedic implants and from environmental or industrial pollution.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Aleaciones de Cromo/farmacología , Macrófagos/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Cuarzo/farmacología , Células Cultivadas , Ensayo Cometa , Fibroblastos/efectos de los fármacos , Fibroblastos/ultraestructura , Humanos , Técnicas In Vitro , Macrófagos/ultraestructura , Fagocitos/efectos de los fármacos
13.
Oncogene ; 25(24): 3424-35, 2006 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-16449970

RESUMEN

There is currently a great interest in delayed chromosomal and other damaging effects of low-dose exposure to a variety of pollutants which appear collectively to act through induction of stress-response pathways related to oxidative stress and ageing. These have been studied mostly in the radiation field but evidence is accumulating that the mechanisms can also be triggered by chemicals, especially heavy metals. Humans are exposed to metals, including chromium (Cr) (VI) and vanadium (V) (V), from the environment, industry and surgical implants. Thus, the impact of low-dose stress responses may be larger than expected from individual toxicity projections. In this study, a short (24 h) exposure of human fibroblasts to low doses of Cr (VI) and V (V) caused both acute chromosome damage and genomic instability in the progeny of exposed cells for at least 30 days after exposure. Acutely, Cr (VI) caused chromatid breaks without aneuploidy while V (V) caused aneuploidy without chromatid breaks. The longer-term genomic instability was similar but depended on hTERT positivity. In telomerase-negative hTERT- cells, Cr (VI) and V (V) caused a long lasting and transmissible induction of dicentric chromosomes, nucleoplasmic bridges, micronuclei and aneuploidy. There was also a long term and transmissible reduction of clonogenic survival, with an increased beta-galactosidase staining and apoptosis. This instability was not present in telomerase-positive hTERT+ cells. In contrast, in hTERT+ cells the metals caused a persistent induction of tetraploidy, which was not noted in hTERT- cells. The growth and survival of both metal-exposed hTERT+ and hTERT- cells differed if they were cultured at subconfluent levels or plated out as colonies. Genomic instability is considered to be a driving force towards cancer. This study suggests that the type of genomic instability in human cells may depend critically on whether they are telomerase-positive or -negative and that their sensitivities to metals could depend on whether they are clustered or diffuse.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Inestabilidad Genómica , Telomerasa/fisiología , Apoptosis , Carcinógenos/toxicidad , Supervivencia Celular , Cromo/farmacología , Aberraciones Cromosómicas , Proteínas de Unión al ADN/metabolismo , Fibroblastos/metabolismo , Humanos , Hibridación Fluorescente in Situ , Iones , Pruebas de Micronúcleos , Telomerasa/metabolismo , Factores de Tiempo , Vanadio/farmacología , beta-Galactosidasa/metabolismo
14.
Biomaterials ; 28(19): 2946-58, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17379299

RESUMEN

Wear debris from metal on polyethylene joint replacements causes asceptic loosening as a result of an inflammatory reaction of macrophages to micron-sized particles. Metal on metal implants, which generate nanoparticles, have been reintroduced into surgical practise in order to avoid this problem. There is a current concern about possible long-term effects of exposure to metal particles. In this study, the cytotoxic and genotoxic effects of nanoparticles and micron-sized particles of cobalt chrome alloy have been compared using human fibroblasts in tissue culture. Nanoparticles, which caused more free radicals in an acellular environment, induced more DNA damage than micron-sized particles using the alkaline comet assay. They induced more aneuploidy and more cytotoxicity at equivalent volumetric dose. Nanoparticles appeared to disintegrate within the cells faster than microparticles with the creation of electron dense deposits in the cell, which were enriched in cobalt. The mechanism of cell damage appears to be different after exposure to nanoparticles and microparticles. The concept of nanotoxicology is, therefore, an important consideration in the design of future surgical devices.


Asunto(s)
Aleaciones de Cromo/toxicidad , Fibroblastos/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Tamaño de la Partícula , Aneuploidia , Células Cultivadas , Aleaciones de Cromo/química , Ensayo Cometa , Citocinas/metabolismo , Daño del ADN , Espectroscopía de Resonancia por Spin del Electrón , Fibroblastos/fisiología , Fibroblastos/ultraestructura , Radicales Libres/metabolismo , Humanos , Ensayo de Materiales , Pruebas de Micronúcleos , Nanotecnología
15.
J Bone Joint Surg Br ; 87(10): 1439-44, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16189324

RESUMEN

Previous research has shown an increase in chromosomal aberrations in patients with worn implants. The type of aberration depended on the type of metal alloy in the prosthesis. We have investigated the metal-specific difference in the level of DNA damage (DNA stand breaks and alkali labile sites) induced by culturing human fibroblasts in synovial fluid retrieved at revision arthroplasty. All six samples from revision cobalt-chromium metal-on-metal and four of six samples from cobalt-chromium metal-on-polyethylene prostheses caused DNA damage. By contrast, none of six samples from revision stainless-steel metal-on-polyethylene prostheses caused significant damage. Samples of cobalt-chromium alloy left to corrode in phosphate-buffered saline also caused DNA damage and this depended on a synergistic effect between the cobalt and chromium ions. Our results further emphasise that epidemiological studies of orthopaedic implants should take account of the type of metal alloy used.


Asunto(s)
Daño del ADN , Prótesis Articulares , Metales/toxicidad , Líquido Sinovial/química , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo , Células Cultivadas , Aleaciones de Cromo , Fibroblastos/efectos de los fármacos , Humanos , Ensayo de Materiales/métodos , Persona de Mediana Edad , Diseño de Prótesis , Acero Inoxidable/toxicidad
16.
AIDS ; 13(15): 2157-64, 1999 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-10546870

RESUMEN

OBJECTIVE: To investigate the relationship between changing morbidity patterns, the use of hospital services by HIV-infected patients and the uptake of antiretroviral therapy (ART) in England. DESIGN: Prospective serial cross-sectional analyses based on data collected through the National Prospective Monitoring System (NPMS), a multi-centre prospective monitoring system. SETTING: HIV-infected patients seen in 10 clinics, five London and five non-London, during the three semesters, 1 January 1996 to 30 June 1997. MAIN OUTCOME MEASURES: The mean use of hospital services per patient-year, mean new HIV-related opportunistic illnesses per 1000 patient-years and percentage uptake of ART. RESULTS: The use of inpatient services changed particularly among AIDS patients. The mean number of inpatient days for AIDS patients decreased from 19.7 [95% confidence interval (CI) 13.7-25.7] in 1996 to 11.2 (95% CI 6.1-15.6) per patient-year in 1997. Concurrently the number of new AIDS-defining events decreased significantly from 567 (95% CI 529-607) to 203 (95% CI 183-225) per 1000 patient-years. The overall uptake of ART increased significantly from 33% (95% CI 31-35%) to 50% (95% CI 48-52%), and a switch from mono or dual to triple therapy or quadruple or more therapy was observed. However, by mid-1997 only 29% (95% CI 26-32%) of asymptomatic patients and 51% (95% CI 49-54%) of patients with symptomatic non-AIDS were on ART, compared with 69% (95% CI 66-71%) of AIDS patients. CONCLUSION: The observed reduction in new AIDS-defining events has led to a reduction in the need for inpatient hospital care and has been associated with an increased uptake of ART, including a switch to triple therapy. All of these factors are likely to have contributed to the observed reduction in mortality among English AIDS patients. As the overall uptake of ART remained relatively low in English centres further improvements can be anticipated. However, the medium to long-term effects of these treatment regimens will need to be closely monitored.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Servicios de Salud/estadística & datos numéricos , Hospitales/estadística & datos numéricos , Morbilidad/tendencias , Estudios Transversales , Quimioterapia Combinada , Inglaterra , Infecciones por VIH/economía , Infecciones por VIH/epidemiología , Infecciones por VIH/mortalidad , Humanos , Estudios Prospectivos
17.
Stroke ; 32(5): 1085-90, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11340214

RESUMEN

BACKGROUND AND PURPOSE: The aim of this study was to establish the difference in burden of cerebrovascular disease across the different health regions of the United Kingdom and to determine whether the initial management of new cases of stroke and transient ischemic attack (TIA) was uniform across the United Kingdom: METHODS: The General Practice Research Database (GPRD) is a national database used for epidemiological studies. This was a cohort study identifying incident cases of stroke and TIA over a 5-year study period between 1992 and 1996. The population studied was patients registered with general practitioners contributing to the GPRD across the different health regions of the United Kingdom: Outcome measures were new diagnoses of stroke and TIA, new prescriptions for antiplatelet and anticoagulant agents, and referrals made for specialist opinion. RESULTS: The age-adjusted annual incidence rate across all regions was 151 per 100 000 for stroke and 190 per 100 000 for TIA. There was almost a 2-fold difference in the incidence of cerebrovascular disease between the regions. The management of stroke and TIA in terms of antiplatelet prescription and of referral onward for further opinion to hospital specialists varied significantly between regions. CONCLUSIONS: Reported stroke and TIA incidence on the GPRD was comparable to that of other European studies. There were striking regional differences in the incidence of disease. The primary care management, both in prescription and referral rates, varied significantly between the different regions. There was a marked underuse of antiplatelet and anticoagulant agents, and referral rates for specialists' opinions were low.


Asunto(s)
Bases de Datos Factuales/estadística & datos numéricos , Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/terapia , Evaluación de Resultado en la Atención de Salud , Pautas de la Práctica en Medicina/estadística & datos numéricos , Atención Primaria de Salud/estadística & datos numéricos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Anticoagulantes/uso terapéutico , Estudios de Cohortes , Utilización de Medicamentos/estadística & datos numéricos , Humanos , Incidencia , Ataque Isquémico Transitorio/epidemiología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Derivación y Consulta/estadística & datos numéricos , Programas Médicos Regionales/estadística & datos numéricos , Reproducibilidad de los Resultados , Accidente Cerebrovascular/epidemiología , Reino Unido/epidemiología
18.
J Hypertens ; 6(8): 627-32, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3183368

RESUMEN

A group of hypertensive patients (n = 2855) with an untreated diastolic blood pressure greater than or equal to 90 mmHg were followed in the Department of Health and Social Security (DHSS) Hypertension Care Computing Project (DHCCP) for periods of up to 10 years. During this period 191 of these patients died. Survival was assessed in relation to pretreatment blood pressure levels and blood pressure achieved during treatment. The blood pressure during treatment was a useful predictor of mortality, but the pretreatment pressure was not. After adjusting for age, mortality was particularly related to the height of the systolic and diastolic blood pressure during the second and third years of treatment. In men, age-standardized 5-year mortality was greater than 10% in those with a first year treated systolic pressure greater than 150 mmHg or a diastolic pressure greater than 95 mmHg. In women, age standardized 5-year mortality was greater than 5% with the same levels of treated blood pressure. The longest survival occurred with the lowest bands of treated pressure, i.e. systolic pressure less than 140 and diastolic pressure less than 90 mmHg; the 5-year mortality being less than 7% in men and less than 3% in women. Treated systolic and diastolic pressures were useful in predicting death from ischaemic heart disease (IHD).


Asunto(s)
Hipertensión/mortalidad , Presión Sanguínea , Femenino , Humanos , Hipertensión/terapia , Masculino
19.
J Hypertens ; 4(1): 93-9, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3958486

RESUMEN

A prospective study has been carried out to determine the causes of death and risk factors for survival in 4994 patients referred with a diagnosis of hypertension to hospital specialist clinics and 457 patients treated by their general practitioners for this condition. At the time of entering the prospective study, 69% of the patients were already being treated for hypertension. Four hundred and eleven patients have died, and their causes of death and death rates have been compared with the rates for the population of England and Wales. Ischaemic heart disease accounted for over one-third of the deaths and stroke for one-fifth. The death rates for these conditions were two to five times those expected for men and women aged 50-59 years and up to twice the rate expected for the age group 60-69 years. Survival in these selected patients was impaired by the following independent risk indicators: cigarette smoking, previous history of myocardial infarction or stroke, diagnosis of angina, impaired renal function and raised blood sugar. The following factors were not independent positive risk factors: smoking a pipe or cigars, obesity, a low plasma potassium and an elevated serum uric acid.


Asunto(s)
Hipertensión/mortalidad , Adolescente , Adulto , Anciano , Glucemia/análisis , Trastornos Cerebrovasculares/complicaciones , Trastornos Cerebrovasculares/mortalidad , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/mortalidad , Inglaterra , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Enfermedades Renales/complicaciones , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Estudios Prospectivos , Riesgo , Fumar , Urea/sangre , Gales
20.
Arch Dermatol ; 136(3): 350-4, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10724196

RESUMEN

CONTEXT: It is well recognized that the presence of a foreskin predisposes to penile carcinoma and sexually transmitted infections. We have investigated the relationship between the presence or absence of the foreskin and penile dermatoses. OBJECTIVE: To determine whether there is an association between circumcision and penile dermatoses. DESIGN: A retrospective case control study of patients attending the department of dermatology with genital skin conditions. SUBJECTS: The study population consisted of 357 male patients referred for diagnosis and management of genital skin disease. The control population consisted of 305 male patients without genital skin disease attending the general dermatology clinics over a 4-month period. MAIN OUTCOME MEASURES: The relationship between circumcision and the presence or absence of skin disease involving the penis was investigated. The rate of circumcision in the general male dermatology population was determined. RESULTS: The most common diagnoses were psoriasis (n = 94), penile infections (n = 58), lichen sclerosus (n = 52), lichen planus (n = 39), seborrheic dermatitis (n = 29), and Zoon balanitis (n = 27). Less common diagnoses included squamous cell carcinoma (n = 4), bowenoid papulosis (n = 3), and Bowen disease (n = 3). The age-adjusted odds ratio for all penile skin diseases associated with presence of the foreskin was 3.24 (95% confidence interval, 2.26-4.64). All patients with Zoon balanitis, bowenoid papulosis, and nonspecific balanoposthitis were uncircumcised. Lichen sclerosus was diagnosed in only 1 circumcised patient. Most patients with psoriasis, lichen planus, and seborrheic eczema (72%, 69%, and 72%, respectively) were uncircumcised at presentation. The majority of men with penile infections (84%) were uncircumcised. CONCLUSIONS: Most cases of inflammatory dermatoses were diagnosed in uncircumcised men, suggesting that circumcision protects against inflammatory dermatoses. The presence of the foreskin may promote inflammation by a köebnerization phenomenon, or the presence of infectious agents, as yet unidentified, may induce inflammation. The data suggest that circumcision prevents or protects against common infective penile dermatoses.


Asunto(s)
Circuncisión Masculina , Enfermedades de los Genitales Masculinos/prevención & control , Enfermedades de la Piel/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Circuncisión Masculina/estadística & datos numéricos , Enfermedades de los Genitales Masculinos/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Retrospectivos , Enfermedades de la Piel/epidemiología
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