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1.
Blood Cancer J ; 11(3): 66, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33771974

RESUMO

Adult T cell leukaemia/lymphoma (ATL) arises from clonally expanded T cells that are infected with human T cell leukaemia virus type-1 (HTLV-1). Here, we show that ATL can be detected early in HTLV-1-carriers through quantification of T-cell receptor (TCR)Vß subunit diversity on T-cells infected with HTLV-1 (CD3+ CCR4+ CD26- T-cells) using an 'oligoclonality index' (OCI-flow). We established a reference range for OCI-flow by analysing peripheral blood mononuclear cells (PBMCs) from HTLV-1-carriers who had not developed ATL in a median of 10.5 years follow up (n = 38) and patients with ATL (n = 30). In the third cohort of HTLV-1-carriers with no history or clinical evidence of ATL (n = 106), 19% of high proviral load (PVL, ≥4 copies of HTLV-1/100 PBMCs) carriers had an OCI-flow in the ATL range, >0.770. Carriers with an OCI-flow >0.770 (n = 14) had higher lymphocyte counts and PVLs and were more likely to have a family history of ATL than carriers with OCI-flow ≤0.770. ATL subsequently developed in two of these 14 carriers but no carriers with OCI-flow ≤0.770 (p = 0.03, cumulative follow-up 129 person-years). This method can be used to identify a subset of high-PVL HTLV-1-carriers at increased risk of developing ATL who may benefit from intervention therapy, prior to the detection of disease.


Assuntos
Infecções por HTLV-I/complicações , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Linfócitos T/virologia , Idoso , Antígenos CD7/análise , Células Cultivadas , Detecção Precoce de Câncer , Feminino , Infecções por HTLV-I/diagnóstico , Humanos , Antígeno Ki-67/análise , Leucemia-Linfoma de Células T do Adulto/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Linfócitos T/patologia
2.
Clin Infect Dis ; 70(7): 1326-1335, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-31063543

RESUMO

BACKGROUND: Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM) is an inflammatory condition characterized by severe disability and high levels of infected white blood cells. The circulating cellular inflammatory changes that distinguish this condition from asymptomatic infection are not well understood. METHODS: To investigate the immune characteristics of individuals with low or high HTLV-1 proviral load (pVL), symptomatic disease, and the impact of immunosuppressive therapy, 38 women living with HTLV-1 infection, at a median age of 59 (52-68) years, were studied. Nineteen were asymptomatic carriers with low or high pVL; 19 were diagnosed with HAM, with 10 receiving anti-inflammatory therapy. Peripheral blood mononuclear cells were stained and analyzed for frequency distribution and activation of innate and adaptive immune cell subsets using multiparameter flow cytometry. RESULTS: Inflation of the CD4:CD8 ratio (>2) was observed among all groups irrespective of pVL. The frequency of naive CD4+ T cells correlated inversely with HTLV-1 pVL (rs = -0.344, P = .026). Mature T effector memory TEM CD4+ T cells were expanded in patients with untreated HAM compared with asymptomatic carriers (P < .001) but less so in those on therapy. High levels of exhausted (PD-1+) and senescent (CD28null) CD4+ and CD8+ T cells were observed in all individuals, particularly in those with HAM, while monocytes showed increased aggregation and CD14+CD56- monocytes were less frequent. CONCLUSIONS: CD4:CD8 ratio inflation is a feature of HTLV-1 infection, whereas enhanced CD4+ T cell maturation and monocyte aggregation are features of HAM, reflecting widespread inflammatory change, which may be detectable presymptomatically and be amenable to anti-inflammatory treatment.


Assuntos
Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Paraparesia Espástica Tropical , Idoso , Feminino , Humanos , Inflamação , Leucócitos Mononucleares , Pessoa de Meia-Idade , Monócitos , Carga Viral
3.
J Steroid Biochem Mol Biol ; 187: 152-159, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30476590

RESUMO

Human rhinoviruses commonly cause upper respiratory infections, which may be complicated by secondary bacterial infection. Vitamin D replacement reduces risk of acute respiratory infections in vitamin D-deficient individuals, but the mechanisms by which such protection is mediated are incompletely understood. We therefore conducted experiments to characterise the influence of the major circulating metabolite 25-hydroxyvitamin D (25[OH]D) and the active metabolite 1,25-dihydroxyvitamin D (1,25[OH]2D) on responses of a respiratory epithelial cell line (A549 cells) to infection with a major group human rhinovirus (RV-16). Pre-treatment of A549 respiratory epithelial cells with a physiological concentration (10-7M) of 25(OH)D induced transient resistance to infection with RV-16 and attenuated RV-16-induced expression of the genes encoding intercellular adhesion molecule 1 (ICAM-1, a cell surface glycoprotein that acts as the cellular receptor for major group rhinoviruses) and platelet-activating factor receptor (PAFR, a G-protein coupled receptor implicated in adhesion of Streptococcus pneumoniae to respiratory epithelial cells). These effects were associated with enhanced expression of the genes encoding the NF-κB inhibitor IκBα and the antimicrobial peptide cathelicidin LL-37. Our findings suggest possible mechanisms by which vitamin D may enhance resistance to rhinovirus infection and reduce risk of secondary bacterial infection in vitamin D-deficient individuals.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/genética , Infecções por Picornaviridae/prevenção & controle , Glicoproteínas da Membrana de Plaquetas/genética , Receptores Acoplados a Proteínas G/genética , Rhinovirus/efeitos dos fármacos , Vitamina D/análogos & derivados , Vitaminas/farmacologia , Células A549 , Calcitriol/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Interações Hospedeiro-Parasita/efeitos dos fármacos , Humanos , Infecções por Picornaviridae/genética , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , Rhinovirus/fisiologia , Vitamina D/farmacologia
4.
Br J Nutr ; 120(8): 891-900, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30132432

RESUMO

SNP in the vitamin D receptor (VDR) gene is associated with risk of lower respiratory infections. The influence of genetic variation in the vitamin D pathway resulting in susceptibility to upper respiratory infections (URI) has not been investigated. We evaluated the influence of thirty-three SNP in eleven vitamin D pathway genes (DBP, DHCR7, RXRA, CYP2R1, CYP27B1, CYP24A1, CYP3A4, CYP27A1, LRP2, CUBN and VDR) resulting in URI risk in 725 adults in London, UK, using an additive model with adjustment for potential confounders and correction for multiple comparisons. Significant associations in this cohort were investigated in a validation cohort of 737 children in Manchester, UK. In all, three SNP in VDR (rs4334089, rs11568820 and rs7970314) and one SNP in CYP3A4 (rs2740574) were associated with risk of URI in the discovery cohort after adjusting for potential confounders and correcting for multiple comparisons (adjusted incidence rate ratio per additional minor allele ≥1·15, P for trend ≤0·030). This association was replicated for rs4334089 in the validation cohort (P for trend=0·048) but not for rs11568820, rs7970314 or rs2740574. Carriage of the minor allele of the rs4334089 SNP in VDR was associated with increased susceptibility to URI in children and adult cohorts in the United Kingdom.


Assuntos
Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Infecções Respiratórias/genética , Viroses/genética , Adulto , Idoso , Citocinas/genética , Citocinas/metabolismo , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Steroid Biochem Mol Biol ; 175: 138-145, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28161533

RESUMO

Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease (COPD), yet a comprehensive analysis of environmental and genetic determinants of serum 25-hydroxyvitamin D (25[OH]D) concentration in patients with this condition is lacking. We conducted a multi-centre cross-sectional study in 278 COPD patients aged 41-92 years in London, UK. Details of potential environmental determinants of vitamin D status and COPD symptom control and severity were collected by questionnaire, and blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction. All participants performed spirometry and underwent measurement of weight and height. Quadriceps muscle strength (QS) was measured in 134 participants, and sputum induction with enumeration of lower airway eosinophil and neutrophil counts was performed for 44 participants. Thirty-seven single nucleotide polymorphisms (SNP) in 11 genes in the vitamin D pathway (DBP, DHCR7, CYP2R1, CYP27B1, CYP24A1, CYP27A1, CYP3A4, LRP2, CUBN, RXRA, and VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration and to determine whether vitamin D status or genetic factors independently associated with % predicted forced expiratory volume in one second (FEV1), % predicted forced vital capacity (FVC), the ratio of FEV1 to FVC (FEV1:FVC), daily inhaled corticosteroid (ICS) dose, respiratory quality of life (QoL), QS, and the percentage of eosinophils and neutrophils in induced sputum. Mean serum 25(OH)D concentration was 45.4nmol/L (SD 25.3); 171/278 (61.5%) participants were vitamin D deficient (serum 25[OH]D concentration <50nmol/L). Lower vitamin D status was independently associated with higher body mass index (P=0.001), lower socio-economic position (P=0.037), lack of vitamin D supplement consumption (P<0.001), sampling in Winter or Spring (P for trend=0.006) and lack of a recent sunny holiday (P=0.002). Vitamin D deficiency associated with reduced % predicted FEV1 (P for trend=0.060) and % predicted FVC (P for trend=0.003), but it did not associate with FEV1:FVC, ICS dose, QoL, QS, or the percentage of eosinophils or neutrophils in induced sputum. After correction for multiple comparisons testing, genetic variation in the vitamin D pathway was not found to associate with serum 25(OH)D concentration or clinical correlates of COPD severity. Vitamin D deficiency was common in this group of COPD patients in the UK, and it associated independently with reduced % predicted FEV1 and FVC. However, genetic variation in the vitamin D pathway was not associated with vitamin D status or severity of COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos Transversais , Sistema Enzimático do Citocromo P-450/sangue , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Ligação a DNA/sangue , Proteínas de Ligação a DNA/genética , Eosinófilos/metabolismo , Eosinófilos/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Londres/epidemiologia , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/sangue , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Neutrófilos/patologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/sangue , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Prevalência , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/genética , Grupos Raciais , Receptores de Calcitriol/sangue , Receptores de Calcitriol/genética , Receptores de Superfície Celular/sangue , Receptores de Superfície Celular/genética , Testes de Função Respiratória , Índice de Gravidade de Doença , Fatores de Transcrição/sangue , Fatores de Transcrição/genética , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/genética
6.
J Steroid Biochem Mol Biol ; 175: 88-96, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27825992

RESUMO

Vitamin D deficiency is common in children with asthma, and it associates with poor asthma control, reduced forced expiratory volume in one second (FEV1) and increased requirement for inhaled corticosteroids (ICS). Cross-sectional studies investigating the prevalence, determinants and clinical correlates of vitamin D deficiency in adults with asthma are lacking. We conducted a multi-centre cross-sectional study in 297 adults with a medical record diagnosis of ICS-treated asthma living in London, UK. Details of potential environmental determinants of vitamin D status, asthma control and medication use were collected by questionnaire; blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction, and participants underwent measurement of weight, height and fractional exhaled nitric oxide concentration (FeNO), spirometry and sputum induction for determination of lower airway eosinophil counts (n=35 sub-group). Thirty-five single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DBP, DHCR7, RXRA, CYP2R1, CYP27B1, CYP24A1, CYP3A4 CYP27A1, LRP2, CUBN, VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration, and to determine whether vitamin D status was independently associated with Asthma Control Test (ACT) score, ICS dose, FeNO, forced vital capacity (FVC), FEV1 or lower airway eosinophilia. Mean serum 25(OH)D concentration was 50.6nmol/L (SD 24.9); 162/297 (54.5%) participants were vitamin D deficient (serum 25(OH)D concentration <50nmol/L). Lower vitamin D status was associated with higher body mass index (P=0.014), non-White ethnicity (P=0.036), unemployment (P for trend=0.012), lack of vitamin D supplement use (P<0.001), sampling in Winter or Spring (P for trend <0.001) and lack of a recent sunny holiday abroad (P=0.030), but not with potential genetic determinants. Vitamin D status was not found to associate with any marker of asthma control investigated. Vitamin D deficiency is common among UK adults with ICS-treated asthma, and classical environmental determinants of serum 25(OH)D operate in this population. However, in contrast to studies conducted in children, we found no association between vitamin D status and markers of asthma severity or control.


Assuntos
Asma/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Administração por Inalação , Adolescente , Corticosteroides/uso terapêutico , Adulto , Idoso , Antiasmáticos/uso terapêutico , Asma/sangue , Asma/complicações , Asma/tratamento farmacológico , Índice de Massa Corporal , Estudos Transversais , Sistema Enzimático do Citocromo P-450/sangue , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Ligação a DNA/sangue , Proteínas de Ligação a DNA/genética , Eosinófilos/metabolismo , Eosinófilos/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Londres/epidemiologia , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/sangue , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Masculino , Pessoa de Meia-Idade , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/sangue , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Grupos Raciais , Receptores de Calcitriol/sangue , Receptores de Calcitriol/genética , Receptores de Superfície Celular/sangue , Receptores de Superfície Celular/genética , Testes de Função Respiratória , Índice de Gravidade de Doença , Fatores de Transcrição/sangue , Fatores de Transcrição/genética , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico
7.
Int J Hematol ; 107(3): 378-382, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29090417

RESUMO

Globally, > 5-10 million people are estimated to be infected with Human T-lymphotropic virus type 1 (HTLV-1), of whom ~ 5% develop adult T-cell leukemia/lymphoma (ATL). Despite advances in chemotherapy, overall survival (OS) has not improved in the 35 years since HTLV-1 was first described. In Europe/USA, combination treatment with zidovudine and interferon-α (ZDV/IFN-α) has substantially changed the management of patients with the leukemic subtypes of ATL (acute or unfavorable chronic ATL) and is under clinical trial evaluation in Japan. However, there is only a single published report of long-term clinical remission on discontinuing ZDV/IFN-α therapy and the optimal duration of treatment is unknown. Anecdotal cases where therapy is discontinued due to side effects or compliance have been associated with rapid disease relapse, and it has been widely accepted that the majority of patients will require life-long therapy. The development of molecular methods to quantify minimal residual disease is essential to potentially guide therapy for individual patients. Here, for the first time, we report molecular evidence that supports long-term clinical remission in a patient who was previously treated with ZDV/IFN-α for 5 years, and who has now been off all therapy for over 6 years.


Assuntos
Antivirais/administração & dosagem , Interferon-alfa/administração & dosagem , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Indução de Remissão , Zidovudina/administração & dosagem , Adulto , Aloenxertos , Transplante de Medula Óssea , Doença Crônica , Terapia Combinada , Quimioterapia Combinada , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Leucemia-Linfoma de Células T do Adulto/virologia , Masculino , Neoplasia Residual/diagnóstico , Fatores de Tempo
8.
United European Gastroenterol J ; 3(3): 294-302, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26137304

RESUMO

BACKGROUND: Vitamin D (vitD) supplementation may prolong remission in Crohn's disease (CD); however, the clinical efficacy and mechanisms are unclear. AIM: To determine changes in intestinal permeability (IP), antimicrobial peptide (AMP) concentrations and disease markers in CD, in response to vitD supplementation. METHODS: In a double-blind randomised placebo-controlled study, we assigned 27 CD patients in remission to 2000 IU/day vitD or placebo for 3 mos. We determined IP, plasma cathelicidin (LL-37 in ng/mL), human-beta-defensin-2 (hBD2 in pg/mL), disease activity (Crohn's Disease Activity Index (CDAI)), C-reactive protein (CRP in mg/L), fecal calprotectin (µg/g), Quality of Life (QoL) and serum 25-hydroxyvitamin D (25(OH)D in nmol/L) at 0 and 3 mos. RESULTS: At 3 mos., 25(OH)D concentrations were significantly higher in those whom were treated (p < 0.001). Intra-group analysis showed increased LL-37 concentrations (p = 0.050) and maintenance of IP measures in the treated group. In contrast, in the placebo group, the small bowel (p = 0.018) and gastro-duodenal permeability (p = 0.030) increased from baseline. At 3 mos., patients with 25(OH)D ≥ 75 nmol/L had significantly lower CRP (p = 0.019), higher QoL (p = 0.037), higher LL-37 concentrations (p < 0.001) and non-significantly lower CDAI scores (p = 0.082), compared to those with levels <75 nmol/L. CONCLUSION: Short-term treatment with 2000 IU/day vitD significantly increased 25(OH)D levels in CD patients in remission and it was associated with increased LL-37 concentrations and maintenance of IP. Achieving 25(OH)D ≥ 75 nmol/l was accompanied by higher circulating LL-37, higher QoL scores and reduced CRP. Registered at ClinicalTrials.gov (NCT01792388).

9.
Nutrients ; 7(6): 4240-70, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26035247

RESUMO

BACKGROUND: Vitamin D deficiency has been shown to be independently associated with increased risk of viral acute respiratory infection (ARI) in a number of observational studies, and meta-analysis of clinical trials of vitamin D supplementation for prevention of ARI has demonstrated protective effects. Several cellular studies have investigated the effects of vitamin D metabolites on immune responses to respiratory viruses, but syntheses of these reports are lacking. SCOPE: In this article, we review the literature reporting results of in vitro experiments investigating immunomodulatory actions of vitamin D metabolites in human respiratory epithelial cells infected with respiratory viruses. KEY FINDINGS: Vitamin D metabolites do not consistently influence replication or clearance of rhinovirus, respiratory syncytial virus (RSV) or influenza A virus in human respiratory epithelial cell culture, although they do modulate expression and secretion of type 1 interferon, chemokines including CXCL8 and CXCL10 and pro-inflammatory cytokines, such as TNF and IL-6. FUTURE RESEARCH: More studies are needed to clarify the effects of vitamin D metabolites on respiratory virus-induced expression of cell surface markers mediating viral entry and bacterial adhesion to respiratory epithelial cells.


Assuntos
Imunidade Inata/efeitos dos fármacos , Imunomodulação , Infecções Respiratórias/imunologia , Viroses/imunologia , Vitamina D/administração & dosagem , Quimiocina CXCL10/metabolismo , Suplementos Nutricionais , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Humanos , Vírus da Influenza A/efeitos dos fármacos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/virologia , Rhinovirus/efeitos dos fármacos , Fatores de Necrose Tumoral/metabolismo , Viroses/tratamento farmacológico , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico
10.
Thorax ; 70(10): 953-60, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26063508

RESUMO

RATIONALE: Low-dose vitamin D supplementation is already recommended in older adults for prevention of fractures and falls, but clinical trials investigating whether higher doses could provide additional protection against acute respiratory infection (ARI) are lacking. OBJECTIVE: To conduct a clinical trial of high-dose versus low-dose vitamin D3 supplementation for ARI prevention in residents of sheltered-accommodation housing blocks ('schemes') and their carers in London, UK. MEASUREMENTS AND METHODS: Fifty-four schemes (137 individual participants) were allocated to the active intervention (vitamin D3 2.4 mg once every 2 months +10 µg daily for residents, 3 mg once every 2 months for carers), and 54 schemes with 103 participants were allocated to control (placebo once every 2 months +vitamin D3 10 µg daily for residents, placebo once every 2 months for carers) for 1 year. Primary outcome was time to first ARI; secondary outcomes included time to first upper/lower respiratory infection (URI/LRI, analysed separately), and symptom duration. MAIN RESULTS: Inadequate vitamin D status was common at baseline: 220/240 (92%) participants had serum 25(OH)D concentration <75 nmol/L. The active intervention did not influence time to first ARI (adjusted HR (aHR) 1.18, 95% CI 0.80 to 1.74, p=0.42). When URI and LRI were analysed separately, allocation to the active intervention was associated with increased risk of URI (aHR 1.48, 95% CI 1.02 to 2.16, p=0.039) and increased duration of URI symptoms (median 7.0 vs 5.0 days for active vs control, adjusted ratio of geometric means 1.34, 95% CI 1.09 to 1.65, p=0.005), but not with altered risk or duration of LRI. CONCLUSIONS: Addition of intermittent bolus-dose vitamin D3 supplementation to a daily low-dose regimen did not influence risk of ARI in older adults and their carers, but was associated with increased risk and duration of URI. TRIAL REGISTRATION NUMBER: clinicaltrials.gov NCT01069874.


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Infecções Respiratórias/prevenção & controle , Vitaminas/uso terapêutico , Doença Aguda , Idoso , Cuidadores , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Casas de Saúde
11.
Thorax ; 70(5): 451-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25724847

RESUMO

RATIONALE: Asthma exacerbations are commonly precipitated by viral upper respiratory infections (URIs). Vitamin D insufficiency associates with susceptibility to URI in patients with asthma. Trials of vitamin D in adults with asthma with incidence of exacerbation and URI as primary outcome are lacking. OBJECTIVE: To conduct a randomised controlled trial of vitamin D3 supplementation for the prevention of asthma exacerbation and URI (coprimary outcomes). MEASUREMENTS AND METHODS: 250 adults with asthma in London, UK were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 (n=125) or placebo (n=125) over 1 year. Secondary outcomes included asthma control test and St George's Respiratory Questionnaire scores, fractional exhaled nitric oxide and concentrations of inflammatory markers in induced sputum. Subgroup analyses were performed to determine whether effects of supplementation were modified by baseline vitamin D status or genotype for 34 single nucleotide polymorphisms in 11 vitamin D pathway genes. MAIN RESULTS: 206/250 participants (82%) were vitamin D insufficient at baseline. Vitamin D3 did not influence time to first severe exacerbation (adjusted HR 1.02, 95% CI 0.69 to 1.53, p=0.91) or first URI (adjusted HR 0.87, 95% CI 0.64 to 1.16, p=0.34). No clinically important effect of vitamin D3 was seen on any of the secondary outcomes listed above. The influence of vitamin D3 on coprimary outcomes was not modified by baseline vitamin D status or genotype. CONCLUSIONS: Bolus-dose vitamin D3 supplementation did not influence time to exacerbation or URI in a population of adults with asthma with a high prevalence of baseline vitamin D insufficiency. TRIAL REGISTRATION NUMBER: NCT00978315 (ClinicalTrials.gov).


Assuntos
Asma/complicações , Asma/prevenção & controle , Colecalciferol/administração & dosagem , Suplementos Nutricionais , Infecções Respiratórias/prevenção & controle , Vitaminas/administração & dosagem , Adulto , Estudos de Coortes , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/epidemiologia , Fatores de Tempo
12.
Lancet Respir Med ; 3(2): 120-130, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25476069

RESUMO

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) often have vitamin D deficiency, which is associated with increased susceptibility to upper respiratory infection-a major precipitant of exacerbation. Multicentre trials of vitamin D supplementation for prevention of exacerbation and upper respiratory infection in patients with COPD are lacking. We therefore investigated whether vitamin D3 (colecalciferol) supplementation would reduce the incidence of moderate or severe COPD exacerbations and upper respiratory infections. METHODS: We did a randomised, double-blind, placebo-controlled trial of vitamin D3 supplementation in adults with COPD in 60 general practices and four Acute National Health Service Trust clinics in London, UK. Patients were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 or placebo over 1 year in a 1:1 ratio using computer-generated permuted block randomisation. Participants and study staff were masked to treatment assignment. Coprimary outcomes were time to first moderate or severe exacerbation and first upper respiratory infection. Analysis was by intention to treat. A prespecified subgroup analysis was done to assess whether effects of the intervention on the coprimary outcomes were modified by baseline vitamin D status. This trial is registered with ClinicalTrials.gov, number NCT00977873. FINDINGS: 240 patients were randomly allocated to the vitamin D3 group (n=122) and placebo group (n=118). Vitamin D3 compared with placebo did not affect time to first moderate or severe exacerbation (adjusted hazard ratio 0·86, 95% CI 0·60-1·24, p=0·42) or time to first upper respiratory infection (0·95, 0·69-1·31, p=0·75). Prespecified subgroup analysis showed that vitamin D3 was protective against moderate or severe exacerbation in participants with baseline serum 25-hydroxyvitamin D concentrations of less than 50 nmol/L (0·57, 0·35-0·92, p=0·021), but not in those with baseline 25-hydroxyvitamin D levels of at least 50 nmol/L (1·45, 0·81-2·62, p=0·21; p=0·021 for interaction between allocation and baseline serum 25-hydroxyvitamin D status). Baseline vitamin D status did not modify the effect of the intervention on risk of upper respiratory infection (pinteraction=0·41). INTERPRETATION: Vitamin D3 supplementation protected against moderate or severe exacerbation, but not upper respiratory infection, in patients with COPD with baseline 25-hydroxyvitamin D levels of less than 50 nmol/L. Our findings suggest that correction of vitamin D deficiency in patients with COPD reduces the risk of moderate or severe exacerbation. FUNDING: UK National Institute for Health Research.


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Doença Pulmonar Obstrutiva Crônica/dietoterapia , Vitaminas/uso terapêutico , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/complicações , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/dietoterapia
13.
J Bone Miner Res ; 28(6): 1301-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23281057

RESUMO

Animal models suggest a key role for dihydroxylated vitamin D metabolites in fracture healing, as evidenced by increases in serum concentration of 24R,25-dihydroxyvitamin D (24R,25[OH]2D) after long bone fracture. Human studies investigating the kinetics of serum concentrations of 24R,25[OH]2D, 1,25-dihydroxyvitamin D (1,25[OH]2D) and their parent metabolite 25-hydroxyvitamin D (25[OH]D) are lacking. We, therefore, conducted a longitudinal study to determine whether total, free, or bioavailable concentrations of these vitamin D metabolites fluctuate in humans after long bone fracture. Twenty-eight patients with cross-shaft (diaphyseal) long bone fracture presenting to an emergency department in London, UK, were studied. Serum concentrations of 25(OH)D, 24R,25(OH)2D, 1,25(OH)2D, vitamin D binding protein, albumin, and calcium were determined within 48 hours of fracture and again at 1 and 6 weeks postfracture. Concentrations of free and bioavailable vitamin D metabolites were calculated using standard equations. No changes in mean serum concentrations of 25(OH)D or 24R,25(OH)2D were seen at either follow-up time point versus baseline. In contrast, mean serum 1,25(OH)2 D concentration declined by 21% over the course of the study, from 68.5 pmol/L at baseline to 54.1 pmol/L at 6 weeks (p < 0.05). This decline was associated with an increase in mean serum corrected calcium concentration, from 2.32 mmol/L at baseline to 2.40 mmol/L at 1 week (p < 0.001) that was maintained at 6 weeks. No changes in free or bioavailable concentrations of any vitamin D metabolite investigated were seen over the course of the study. We conclude that serum 1,25(OH)2D concentration declines after long bone fracture in humans but that the serum 24R,25(OH)2D concentration does not fluctuate. The latter finding contrasts with those of animal models reporting increases in serum 24R,25(OH)2D concentration after long bone fracture.


Assuntos
24,25-Di-Hidroxivitamina D 3/sangue , Calcitriol/sangue , Fraturas Ósseas/sangue , Adulto , Idoso , Albuminas/metabolismo , Serviço Hospitalar de Emergência , Feminino , Seguimentos , Fraturas Ósseas/patologia , Fraturas Ósseas/terapia , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Proteína de Ligação a Vitamina D/sangue
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