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Several methods could be used to measure the forces from skis or roller skis in cross-country skiing. Equipment that could measure medio-lateral forces may be of good help for investigating the relevant skating techniques. The aim of this study was to validate a pair of newly designed two-dimensional force measurement roller skis. The vertical and medio-lateral forces which were perpendicular to the body of the roller ski could be measured. Forces were resolved into the global coordinate system and compared with the force components measured by a force plate. A static and dynamic loading situation for the force measurement roller ski was performed to reveal the validity of the system. To demonstrate whether the force measurement roller ski would affect roller skiing performance on a treadmill, a maximum speed test with the V2 technique was performed by using both normal and force measurement roller skis. The force-time curves obtained by these two different force measurement systems were shown to have high similarity (coefficient of multiple correlations > 0.940). The absolute difference for the forces in the X and Z directions over one push-off cycle was 3.9−33.3 N. The extra weight (333 g) of the force measurement roller ski did not affect the performance of the skiers. Overall, the newly designed two-dimensional force measurement roller ski in this study is valid for use in future research during daily training for skate skiing techniques.
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Patinação , Esqui , Teste de Esforço , Fenômenos BiomecânicosRESUMO
BACKGROUND AND OBJECTIVES: Options to treat and prevent episodic wheezing in children are scarce. Our objective was to assess the efficacy of intermittent tiotropium bromide treatment in early childhood episodic wheezing. METHODS: This 48-week, randomized, open-label, controlled, parallel-group trial was conducted at 4 hospitals in Finland. Children aged 6 to 35 months with 2 to 4 physician-confirmed episodes of wheeze and/or shortness of breath were considered eligible. Study participants were randomly allocated to receive 1 of 3 treatments: once-daily tiotropium bromide 5 µg for 7 to 14 days during respiratory tract infections and as-needed albuterol sulfate 0.2 mg (n = 27), twice-daily fluticasone propionate 125 µg for 7 to 14 days during respiratory tract infections and as-needed albuterol sulfate 0.2 mg (n = 25), or as-needed albuterol sulfate 0.2 mg alone (n = 28). The primary outcome was efficacy, assessed as intention-to-treat by comparing the proportion of episode-free days (the days lacking symptoms or treatments) between the treatment groups. RESULTS: The proportion of episode-free days was higher in those receiving intermittent tiotropium bromide (median 97% [interquartile range, 93% to 99%]) than in those receiving intermittent fluticasone propionate (87% [78% to 93%], P = .002), or with as-needed albuterol sulfate alone (88% [79% to 95%], P = .003). Adjustment with allergic sensitization, the baseline number of physician-confirmed episodes of wheeze and/or shortness of breath, or short-course glucocorticoid treatment in the 2 weeks before the enrollment, did not affect the result. Intervention-related adverse events were not seen. CONCLUSIONS: Intermittent tiotropium bromide treatment may be an effective alternative to current therapies for episodic wheezing. Before implementation of use, further research on safety and efficacy is indicated.
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Sons Respiratórios , Infecções Respiratórias , Albuterol/uso terapêutico , Broncodilatadores/uso terapêutico , Criança , Pré-Escolar , Método Duplo-Cego , Dispneia/tratamento farmacológico , Fluticasona/uso terapêutico , Humanos , Brometo de Tiotrópio/uso terapêutico , Resultado do TratamentoRESUMO
BACKGROUND: Increasing evidence shows that environmental factors in childhood play a role in development of irreversible airway obstruction. We evaluated early-life and preschool-age risk factors for irreversible airway obstruction in adolescence after bronchiolitis in infancy. METHODS: This study is a secondary analysis of data collected during prospective long-term follow-up of our post-bronchiolitis cohort. Risk factor data were collected during hospitalisation and on follow-up visits at 5-7 and 10-13 years of ages. Lung function was measured from 103 participants with impulse oscillometry at 5-7 years of age and from 89 participants with flow-volume spirometry at 10-13 years of age. RESULTS: Asthma diagnosis at <12 months of age showed a significant association with irreversible airway obstruction at 10-13 years of age independently from current asthma. Irreversible airway obstruction was less frequent in children with variant than wild genotype of the Toll-like receptor 4(TLR4) rs4986790, but the significance was lost in logistic regression adjusted for current asthma and weight status. Higher post-bronchodilator respiratory system resistance at 5 Hz and lower baseline and post-bronchodilator reactance at 5 Hz by impulse oscillometry at 5-7 years of age were associated with irreversible airway obstruction at 10-13 years of age. CONCLUSION: Asthma diagnosis during the first living year and worse lung function at preschool age increased the risk for irreversible airway obstruction at 10-13 years of age after bronchiolitis. TLR4 rs4986790 polymorphism may be protective for development of irreversible airway obstruction after bronchiolitis.
Assuntos
Obstrução das Vias Respiratórias/etiologia , Asma/complicações , Bronquiolite/complicações , Adolescente , Fatores Etários , Obstrução das Vias Respiratórias/diagnóstico , Obstrução das Vias Respiratórias/epidemiologia , Obstrução das Vias Respiratórias/genética , Resistência das Vias Respiratórias/fisiologia , Asma/fisiopatologia , Bronquiolite/fisiopatologia , Criança , Pré-Escolar , Feminino , Seguimentos , Genótipo , Humanos , Masculino , Oscilometria , Polimorfismo Genético , Estudos Prospectivos , Fatores de Risco , Espirometria , Fatores de Tempo , Receptor 4 Toll-Like/genéticaRESUMO
AIM: Interleukin-10 (IL-10) is an anti-inflammatory cytokine that is involved with bronchiolitis and asthma. We evaluated associations between four IL-10 polymorphisms, namely rs1800871, rs1800872, rs1800890 and rs1800896, and post-bronchiolitis asthma in young adolescents. METHODS: The cohort consisted of 125 children hospitalised for bronchiolitis at Tampere University Hospital, Finland, in 2000-2004, at less than six months of age. At 11-13 years, asthma diagnoses and asthma-presumptive symptoms, allergic rhinitis and use of inhaled corticosteroids (ICS) were registered. Data on the four polymorphisms and their genotypes, haplotypes and allele frequencies were analysed in relation to asthma, allergic rhinitis and asthma medication. RESULTS: The variant IL-10 rs1800896 genotype was associated with less persistent asthma at five to seven and 11-13 years of age (4.3 versus 15.2%, p = 0.04) than the wild genotype and less ICS use during the previous 12 months (5.4 versus 18.2%, p = 0.03), as was the variant allele G. Allele A was associated with more persistent asthma and ICS use. The significant differences between the variant and wild genotypes were lost in adjusted logistic regression, but the direction of the association remained. CONCLUSION: IL-10 rs1800896 gene polymorphism was associated with post-bronchiolitis asthma at 11-13 years of age in children hospitalised for bronchiolitis at less than six months of age.
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Asma/etiologia , Asma/genética , Bronquiolite/complicações , Interleucina-10/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Criança , Estudos de Coortes , Feminino , Genótipo , Humanos , Lactente , Masculino , Estudos ProspectivosRESUMO
AIM: This study evaluated children hospitalised for bronchiolitis at less than six months of age to see if they had reduced lung function in early adolescence. METHODS: We have prospectively followed 166 children hospitalised for infant bronchiolitis in 2001-2004 at Tampere University Hospital, Finland. At 10-13 years of age, flow-volume spirometry was measured in 89 cases and 108 controls without infant bronchiolitis from the local population register. Parameters of flow-volume spirometry before and after bronchodilation were analysed. RESULTS: Forced expiratory volume in one second/forced vital capacity (FEV1/FVC) after bronchodilation was lower in cases than controls. FEV1 was pathological - under the 5th percentile of the national references - in 25% of cases and 12% of controls (p = 0.020) before bronchodilation and in 18% of cases and 5% of controls (p = 0.003) after bronchodilation. FEV1/FVC was pathological in 25% of cases and 13% of controls (p = 0.034) before bronchodilation. Logistic regression, adjusted for current asthma and maternal smoking, showed that infant bronchiolitis was associated with pathological FEV1 before (odds ratio 2.4) and after (odds ratio 4.4) bronchodilation. The result was similar for positive respiratory syncytial virus cases. CONCLUSION: Reduced FEV1 after bronchodilation was found in early adolescence after infant bronchiolitis, suggesting irreversible bronchial obstruction.
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Corticosteroides/administração & dosagem , Bronquiolite/complicações , Bronquiolite/tratamento farmacológico , Insuficiência Respiratória/epidemiologia , Espirometria/métodos , Administração por Inalação , Adolescente , Distribuição por Idade , Bronquiolite/diagnóstico , Criança , Intervalos de Confiança , Estudos Transversais , Feminino , Finlândia , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Monitorização Fisiológica/métodos , Razão de Chances , Estudos Prospectivos , Testes de Função Respiratória , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/fisiopatologia , Medição de Risco , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Bronchiolitis is the most common infection leading to hospitalization in infancy. Interleukin-10 (IL-10) is an anti-inflammatory cytokine, and in our previous study, IL10 gene rs1800896 (- 1082A/G) polymorphism was associated with viral etiology of infant bronchiolitis. The objective of this study was to evaluate the associations between IL10 single nucleotide polymorphisms (SNPs) at rs1800890 (- 3575A/T), rs1800871 (- 819C/T) or rs1800872 (- 592C/A) either alone or combined with the SNP at rs1800896 (- 1082G/A), and the etiology and severity of infant bronchiolitis. METHODS: Data on four IL10 SNPs were available from 135 full-term infants, hospitalized for bronchiolitis at age less than 6 months, and from 378 to 400 controls. Viral etiology was studied, and oxygen support, feeding support and the length of stay in hospital were recorded during bronchiolitis hospitalization. RESULTS: Infants with rhinovirus bronchiolitis had the IL10 rs1800890 variant AT or TT genotype less often (18.2%) than controls (63.3%, P = 0.03), and likewise, had the IL10 rs1800896 variant AG or GG genotype less often (27.3%) than controls (65.5%, P = 0.009). Twenty-eight infants with bronchiolitis had the variant-variant Grs1800896Trs1800890 haplotype, and none of them had rhinovirus infection. The IL10 rs1800871 or rs1800872 genotypes showed no associations with viruses. No association was found between any genotypes and bronchiolitis severity measures. CONCLUSION: IL10 rs1800890 and rs1800896 polymorphisms differed between infants with rhinovirus bronchiolitis and controls, but not between infants with respiratory syncytial virus bronchiolitis and controls.
Assuntos
Bronquiolite/virologia , Interleucina-10/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Lactente , Recém-Nascido , Masculino , Infecções por Picornaviridae/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , RhinovirusRESUMO
BACKGROUND: The transition from early childhood wheezing to persistent asthma is linked to lung function impairment over time. Little is known how the methods used to study lung function at different ages correlate longitudinally. METHODS: Sixty-four children with a history of hospitalization for bronchiolitis before 6 months of age were prospectively studied with impulse oscillometry (IOS) at the mean age of 6.3 years and these preschool IOS results were compared with flow-volume spirometry (FVS) measurements at mean age of 11.4 years. RESULTS: The baseline respiratory system resistance at 5 Hz (Rrs5) showed a modest statistically significant correlation with all baseline FVS parameters except FVC. The post-bronchodilator (post-BD) Rrs5 showed a modest statistically significant correlation with post-BD FEV1 and FEV1 /FVC. The bronchodilator-induced decrease in Rrs5 showed a modest statistically significant correlation with the percent increase in FEV1 . Baseline and post-BD respiratory reactance at 5 Hz (Xrs5) showed a modest statistically significant correlation with baseline and post-BD FVS parameters except post-BD FEV1 /FVC, respectively, and post-BD Xrs5 showed a strong correlation with post-BD FVC (ρ = 0.61) and post-BD FEV1 (ρ = 0.59). In adjusted linear regression, preschool Xrs5 remained as a statistically significant independent predictor of FVS parameters in adolescence; the one-unit decrease in the Z-score of preschool post-BD Xrs5 predicted 9.6% lower post-BD FEV1 , 9.3% lower post-BD FVC, and 9.7% lower post-BD MEF50 when expressed as %-predicted parameters. CONCLUSION: Persistent post-BD small airway impairment in children with a history of bronchiolitis detected with IOS at preschool age predicted FVS results measured in early adolescence.
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Asma/fisiopatologia , Bronquiolite/fisiopatologia , Volume Expiratório Forçado/fisiologia , Oscilometria , Espirometria , Asma/diagnóstico , Bronquiolite/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Oscilometria/métodos , Valor Preditivo dos Testes , Estudos Prospectivos , Espirometria/métodos , Fatores de TempoRESUMO
BACKGROUND AND AIM: Bronchiolitis is a leading cause of hospitalization in infants and is associated with a risk of subsequent asthma. The innate immunity genes, such as those encoding toll-like receptors (TLRs), are likely to play a role in bronchiolitis and post-bronchiolitis outcome. Thus far, only one study has considered TLR5 genes in respiratory syncytial virus (RSV) bronchiolitis. The aim of this study was to investigate the association of TLR5 gene polymorphism with virus etiology and severity of bronchiolitis, and with post-bronchiolitis asthma. METHODS: We recruited 164 infants (age < 6 months) hospitalized for bronchiolitis in this study and determined TLR5 rs5744174 (C > T) single nucleotide polymorphism, virus etiology and severity markers of bronchiolitis, and presence of post-bronchiolitis asthma until age 11 to 13 years. RESULTS: RSV was detected in 113 (68.9%), rhinovirus in 19 (11.6%), and some other virus in 20 (12.2%) cases. Non-RSV etiology was more common among infants with the variant CT or TT genotype in the TLR5 rs5744174 gene than in those with the CC genotype (89.7% vs 71.7%, P = 0.03). TLR5 rs5744174 polymorphism was not associated with the need of supplementary oxygen or feeding support, with the length of hospital stay, or with post-bronchiolitis asthma at any age. CONCLUSION: The TLR5 rs5744174 variant genotype may increase the susceptibility to bronchiolitis not caused by RSV.
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AIM: Toll-like receptors (TLR) are innate immunity molecules and our previous studies found that TLR1 gene polymorphism was associated with postbronchiolitis asthma at one to six years of age, as was TLR10 at five to seven years of age. This study examined any associations at 11-13 years of age. METHODS: This prospective follow-up study was part of an ongoing evaluation of children admitted to Tampere University Hospital, Finland, for bronchiolitis in 2001-2004 at less than six months of age. We evaluated the association of TLR1 rs5743618 and TLR10 rs4129009 polymorphisms with asthma and asthma medication in 125 children aged 11-13 years. RESULTS: Associations were measured as adjusted odd ratios (aOR) with 95% confidence intervals (95% CI). The variant TLR1 rs5743618 (aOR 4.04, 95% CI 0.99-13.01) and TLR10 rs4129009 (aOR 7.02, 95% CI 1.56-31.53) genotypes increased the risk of needing inhaled corticosteroids (ICSs) at 11-13 years of age. The variant TLR10 genotype (aOR 7.69, 95% CI 1.35-43.95) increased the risk of persistent asthma continuing from five to seven years of age until 11-13 years of age. The results were similar when the combined genotypes were analysed. [Correction added on 3 October 2017, after online publication: The data in the variant TRL1 rs5743618 genotype were incorrect and have been corrected in this version.] CONCLUSION: Polymorphisms in both the TLR1 and TLR10 genes may increase the risk of asthma at 11-13 years after infant bronchiolitis.
Assuntos
Asma/etiologia , Bronquiolite/complicações , Receptor 10 Toll-Like/genética , Receptor 1 Toll-Like/genética , Adolescente , Criança , Feminino , Seguimentos , Humanos , Masculino , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: Interleukin-17 (IL-17A) is a mainly pro-inflammatory cytokine, and IL-17 signaling implicates in the development of allergic asthma. The polymorphism rs2275913 in the promoter region of the IL-17A gene has in previous studies been associated with asthma susceptibility. The objective was to evaluate the association between IL-17A rs2275913 (-197G>A) polymorphism and post-bronchiolitis asthma and/or allergic rhinitis in a prospective 11-13 years post-bronchiolitis follow-up. METHODS: 166 previously healthy full-term infants, hospitalized for bronchiolitis at age less than 6 months, were invited to follow-up visits at the ages of 5-7 years and 11-13 years. Asthma diagnoses and presumptive symptoms, allergic rhinitis and use of inhaled corticosteroids (ICS) were registered. Blood samples for IL-17A rs2275913 (-197G>A) polymorphism were obtained during hospitalization or at the 5-7 years control visit. RESULTS: There were no significant differences between children with the wild GG and variant GA or AA genotype in the severity of bronchiolitis during hospitalization or in the outcomes until the age 5-7 years. At 11-13 years of age, children with the variant GA or AA genotype had significantly less often current asthma, use of ICSs during last 12 months or allergic rhinitis than those with the wild GG genotype. The ICS use during last 12 months retained the statistical significance in adjusted analyses (adjusted OR 0.25), whereas current asthma and allergic rhinitis marginally lost it. CONCLUSIONS: The IL-17A rs2275913 (-197G>A) polymorphism decreased the risk of post-bronchiolitis asthma at 11-13 years of age, but not earlier in life, in the present prospective, long-term follow-up study.
Assuntos
Asma , Bronquiolite , Interleucina-17/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Adolescente , Fatores Etários , Asma/epidemiologia , Asma/etiologia , Asma/genética , Bronquiolite/complicações , Bronquiolite/epidemiologia , Bronquiolite/genética , Criança , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de RiscoRESUMO
Toll-like receptors (TLRs) recognise microbes that contribute to the severity of bronchiolitis and the subsequent risk of asthma. We evaluated whether post-bronchiolitis asthma was associated with polymorphisms in the TLR3 rs3775291, TLR4 rs4986790, TLR7 rs179008, TLR8 rs2407992, TLR9 rs187084, and TLR10 rs4129009 genes. The gene polymorphisms were studied at the age of 6.4 years (mean) in 135 children hospitalised for bronchiolitis in infancy. The outcome measure was current or previous asthma. Current asthma was more common (30%) in children with the variant AG or GG genotype in the TLR10 rs4129009 gene versus those who were homozygous for the major allele A (11%) (p = 0.03). The adjusted odds ratio (aOR) was 4.30 (95% CI 1.30-14.29). Asthma ever was more common (34.6%) in girls with the TLR7 variant AT or TT genotype versus those who were homozygous for the major allele A (12.5%) (p = 0.03). The adjusted OR was 3.93 (95% CI 1.06-14.58). Corresponding associations were not seen in boys. There were no significant associations between TLR3, TLR4, TLR8, or TLR9 polymorphisms and post-bronchiolitis asthma. Polymorphism in the TLR10 gene increases and in the TLR7 gene may increase the risk of asthma in preschool-aged children after infant bronchiolitis.
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Asma/etiologia , Bronquiolite/complicações , Bronquiolite/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Receptor 10 Toll-Like/genética , Alelos , Asma/diagnóstico , Criança , Pré-Escolar , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Família Multigênica , Receptores Toll-Like/genéticaRESUMO
AIM: Infants hospitalised for bronchiolitis undergo examinations and treatments not supported by current research evidence and we investigated practice variations with regard to Finnish children under the age of two. METHODS: This prospective, multicentre cohort study was conducted in paediatric units in three university hospitals in Finland from 2008 to 2010. Hospital medical records were reviewed to collect data on clinical course, testing and treatment. Data were analysed separately for children meeting our strict definition of bronchiolitis, aged under 12 months without a history of wheezing, and a loose definition, aged 12-23 months or with a history of wheezing. RESULTS: The median age of the 408 children was 8.1 months. Clinical management varied between the three hospitals when stratified by strict and loose bronchiolitis subgroup definitions: complete blood counts ranged from 15-95% vs 16-94%, respectively, and the other measures were chest x-ray (16-91% vs 14-72%), intravenous fluids (2-47% vs 2-41%), use of nebulised epinephrine (10-84% vs 7-50%), use of salbutamol (18-21% vs 13-84%) and use of corticosteroids (6-23% vs 60-76%). CONCLUSION: The clinical management of bronchiolitis varied considerably with regard to the three hospitals and the two definitions of bronchiolitis. A stronger commitment to evidence-based bronchiolitis guidelines is needed in Finland.
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Albuterol/administração & dosagem , Bronquiolite/tratamento farmacológico , Broncodilatadores/administração & dosagem , Epinefrina/administração & dosagem , Administração por Inalação , Bronquiolite/epidemiologia , Estudos de Coortes , Feminino , Finlândia/epidemiologia , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
BACKGROUND: Variations in the genes that regulate innate immunity responses may be associated with susceptibility to asthma or atopy after early-life bronchiolitis. The aim of this study was to evaluate the association between four different polymorphisms of the IL-10 gene at rs1800871, rs1800872, rs1800890, and rs1800896, either alone or in combination, and post-bronchiolitis asthma or allergies at 5-7 years of age. METHODS: Data on single nucleotide polymorphisms (SNP) of IL-10 rs1800896 (-1082G/A), rs1800871 (-819C/T), rs1800872 (-592C/A), and IL-10 rs1800890 (-3575T/A) were available for 135 children. Polymorphisms and their associations with asthma and allergies were studied in 135 preschool-aged children who had been hospitalized for bronchiolitis at age 0-6 months. Their parents were interviewed to record the children's history with asthma and allergies from infancy to the present. RESULTS: At 6.4 years (mean), asthma was present in 17 children (12.6%), while recurrent wheezing during the first 7 years of life was present in 39 (28.9%) children. Fifty-three (39.3%) study participants had current atopy (atopic eczema or allergic rhinitis). Eight (72%) of 11 children with the IL-10 rs1800896, IL-10 rs1800871, and IL-10 rs1800872 combination AA + CT + CA had current atopy (P = 0.02 vs. 38% in other genotype combinations). Twenty-three (56%) children with the IL-10 rs1800871C/T or IL-10 rs1800872C/A genotype had present atopy versus 34 (38%) with other IL-10 genotypes (P = 0.03). Between 2 years and 3 years of age, 27% of ATA haplotype carriers had asthma versus 13.7% of other haplotype carriers (P = 0.02). CONCLUSIONS: IL-10 polymorphisms at rs1800871, rs1800872, rs1800890, and rs1800896 seem to be associated with elevated allergies and/or recurrent wheezing risk in later childhood, after early-life bronchiolitis. Pediatr Pulmonol. 2017;52:14-20. © 2016 Wiley Periodicals, Inc.
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Asma/genética , Bronquiolite/genética , Dermatite Atópica/genética , Interleucina-10/genética , Polimorfismo de Nucleotídeo Único , Sons Respiratórios , Rinite Alérgica/genética , Asma/complicações , Bronquiolite/complicações , Criança , Pré-Escolar , Dermatite Atópica/complicações , Feminino , Genótipo , Haplótipos , Humanos , Lactente , Masculino , Rinite Alérgica/complicaçõesRESUMO
Innate immunity receptors play a critical role in host defence, as well as in allergy and asthma. The aim of this exploratory study was to evaluate whether there are associations between TLR7 rs179008, TLR8 rs2407992, TLR9 rs187084 or TLR10 rs4129009 polymorphisms and viral findings, clinical characteristics or subsequent wheezing in infants with bronchiolitis. In all, 135 full-term infants were hospitalized for bronchiolitis at age less than 6 months: 129 of them were followed-up until the age of 1.5 years. The outcome measures were repeated wheezing, use of inhaled corticosteroids, atopic dermatitis during the first 1.5 years of life and total serum immunoglobulin E (IgE). There were no significant associations between the genotypes or allele frequencies of TLR7 rs179008, TLR8 rs2407992, TLR9 rs187084 or TLR10 rs4129009 polymorphisms and clinical characteristics or the severity of bronchiolitis during hospitalization. During follow-up, repeated wheezing was more common in children with TLR9 rs187084 variant genotype CC (30.5%) than in children with TLR9 wild-type genotype TT (12.2%) (p = 0.02, aOR 2.73, 95% CI 1.02-7.29). The TLR10 rs4129009 minor allele G was associated with elevated total serum IgE. TLR9 rs187084 gene polymorphism may be associated with post-bronchiolitis wheezing, and TLR10 rs4129009 gene polymorphism may be associated with atopy.
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Bronquiolite/genética , Polimorfismo Genético , Sons Respiratórios/genética , Receptor Toll-Like 9/genética , Feminino , Seguimentos , Humanos , Lactente , MasculinoRESUMO
AIM: The united airway disease (UAD) hypothesis suggests that allergic rhinitis and asthma develop together. We evaluated the evidence for and against the UAD hypothesis at five to seven years of age after hospitalisation for bronchiolitis at less than six months. METHODS: This study used prospective follow-up data for 102 children hospitalised for bronchiolitis under the age of six months. We included the presence of previous and current asthma, prolonged rhinitis and skin prick tests (SPT) to common inhaled allergens and lung function by impulse oscillometry (IOS) at five to seven years of age. Bronchial hyper-reactivity (BHR) was assessed using the exercise challenge test and bronchodilation test. RESULTS: Current asthma, but not previous transient asthma, was associated with prolonged rhinitis and a positive SPT. BHR, which reflected reactive airways, but not lung function, was associated with respiratory allergy, namely the combination of current asthma, prolonged rhinitis and a positive SPT. CONCLUSION: This post-bronchiolitis follow-up study suggested an association between respiratory allergy and reactive airways at five to seven years of age, which supported the UAD hypothesis. However, previous transient asthma and a reduction in lung function reduction did not support the hypothesis.
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Resistência das Vias Respiratórias/imunologia , Bronquiolite/complicações , Hipersensibilidade Respiratória/diagnóstico , Resistência das Vias Respiratórias/fisiologia , Alérgenos/efeitos adversos , Alérgenos/imunologia , Asma/etiologia , Asma/fisiopatologia , Bronquiolite/diagnóstico , Bronquiolite/fisiopatologia , Criança , Pré-Escolar , Seguimentos , Humanos , Lactente , Hipersensibilidade Respiratória/etiologia , Hipersensibilidade Respiratória/fisiopatologia , Rinite Alérgica/diagnóstico , Rinite Alérgica/etiologia , Rinite Alérgica/fisiopatologia , Testes Cutâneos , Espirometria/estatística & dados numéricosRESUMO
AIM: Toll-like receptors (TLR) play a crucial role in innate immunity, protecting the host from pathogens such as viruses. Genetic variations in TLRs have been associated with the severity of viral bronchiolitis in infancy and with the later occurrence of post-bronchiolitis asthma. The aim of the present study was to evaluate if there are any exploratory associations between TLR gene polymorphisms and lung function at 5 to 7 years of age in former bronchiolitis patients. METHODS: We performed impulse oscillometry (IOS) at the median age of 6.3 years for 103 children who had been hospitalized for bronchiolitis at less than six months of age. The main parameters evaluated were airway resistance and reactance at 5Hz in baseline and post-exercise measurements. Data on single nucleotide polymorphisms (SNP) of TLR1 rs5743618, TLR2 rs5743708, TLR6 rs5743810 and TLR10 rs4129009 (TLR2 subfamily) and TLR3 rs3775291, TLR4 rs4986790, TLR7 rs179008, TLR8 rs2407992 and TLR 9 rs187084 were available for analyses. RESULTS: The TLR4 rs4986790 wild genotype A/A was associated with a greater Rrs5 response (0.72 vs. -0.42, p = 0.03) to exercise. In TLR6 rs5743810, the minor allele T was associated with greater Rrs5 response (0.80 vs. -0.03, p = 0.04) to exercise. In TLR7 rs179008, the major allele A was associated with baseline decline in dRrs/df (-1.03 vs 0.61, p = 0.01) and increased Fres (2.28 vs. 0.89, p = 0.01) in girls. CONCLUSION: Among the nine studied TLRs, only TLR7 rs179008 showed some exploratory associations with post-bronchiolitis lung function deficiency, and polymorphisms of TLR4 rs4986790, and TLR6 rs5743810 in particular, with airway reactivity. These findings call for further confirmatory studies.
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Pulmão/fisiopatologia , Receptor 4 Toll-Like/genética , Receptor 6 Toll-Like/genética , Receptor 7 Toll-Like/genética , Resistência das Vias Respiratórias , Bronquiolite/genética , Criança , Pré-Escolar , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The application of White Rabbit precision time protocol (WR-PTP) in long-distance optical fiber links has been investigated. WR-PTP is an implementation of PTP in synchronous Ethernet optical fiber networks, originally intended for synchronization of equipment within a range of 10 km. This paper discusses the results and limitations of two implementations of WR-PTP in the existing communication fiber networks. A 950-km WR-PTP link was realized using unidirectional paths in a fiber pair between Espoo and Kajaani, Finland. The time transfer on this link was compared (after initial calibration) against a clock comparison by GPS precise point positioning (PPP). The agreement between the two methods remained within [Formula: see text] over three months of measurements. Another WR-PTP implementation was realized between Delft and Amsterdam, the Netherlands, by cascading two links of 137 km each. In this case, the WR links were realized as bidirectional paths in single fibers. The measured time offset between the starting and end points of the link was within 5 ns with an uncertainty of 8 ns, mainly due to the estimated delay asymmetry caused by chromatic dispersion.
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In 169 Finnish infants hospitalized for bronchiolitis at age <6 months in 2008-2010, nasopharyngeal aspirates were tested by polymerase chain reaction for Bordetella pertussis and 16 viruses. Respiratory viruses were detected in 89% (71% with respiratory syncytial virus), but no infant had B. pertussis. The latter finding may reflect a positive effect from the broadening of the Finnish pertussis vaccination program in 2005.