human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Low serum 25-hydroxyvitamin D ( 25-[OH]D ) levels have been associated with lower FEV(1 ) , impaired immunologic control , and increased airway inflammation . Because many patients with chronic obstructive pulmonary disease ( COPD ) have vitamin D deficiency , effects of vitamin D supplementation may extend beyond preventing osteoporosis . OBJECTIVE To explore whether supplementation with high doses of vitamin D could reduce the incidence of COPD exacerbations . DESIGN R and omized , single-center , double-blind , placebo-controlled trial . ( Clinical Trials.gov registration number : NCT00666367 ) SETTING University Hospitals Leuven , Leuven , Belgium . PATIENTS 182 patients with moderate to very severe COPD and a history of recent exacerbations . INTERVENTION 100,000 IU of vitamin D supplementation or placebo every 4 weeks for 1 year . MEASUREMENTS The primary outcome was time to first exacerbation . Secondary outcomes were exacerbation rate , time to first hospitalization , time to second exacerbation , FEV(1 ) , quality of life , and death . RESULTS Mean serum 25-(OH)D levels increased significantly in the vitamin D group compared with the placebo group ( mean between-group difference , 30 ng/mL [ 95 % CI , 27 to 33 ng/mL ] ; P < 0.001 ) . The median time to first exacerbation did not significantly differ between the groups ( hazard ratio , 1.1 [ CI , 0.82 to 1.56 ] ; P = 0.41 ) , nor did exacerbation rates , FEV(1 ) , hospitalization , quality of life , and death . However , a post hoc analysis in 30 participants with severe vitamin D deficiency ( serum 25-[OH]D levels < 10 ng/mL ) at baseline showed a significant reduction in exacerbations in the vitamin D group ( rate ratio , 0.57 [ CI , 0.33 to 0.98 ] ; P = 0.042 ) . LIMITATION This was a single-center study with a small sample size . CONCLUSION High-dose vitamin D supplementation in a sample of patients with COPD did not reduce the incidence of exacerbations . In participants with severe vitamin D deficiency at baseline , supplementation may reduce exacerbations . PRIMARY FUNDING SOURCE Applied Biomedical Research Program , Agency for Innovation by Science and Technology ( IWT-TBM ) Objective To investigate whether vitamin D supplementation can decrease the mortality and morbidity of low birthweight infants in low income countries . Design R and omised controlled trial . Setting Large government hospital in New Delhi , India . Participants 2079 low birthweight infants born at term ( > 37 weeks ’ gestation ) . Main outcome measures Primary outcome was admission to hospital or death during the first six months of life . Main secondary outcome was growth . Interventions Weekly vitamin D supplements for six months at a dose of one recommended nutrient intake per day ( 35 µg/week ) . Infants were visited weekly at home for observed supplementation and were brought to the clinic monthly for clinical examination and anthropometric measurements . Results Between group differences were not significant for death or hospital admissions ( 92 among 1039 infants in the vitamin D group v 99 among 1040 infants in the placebo group ; adjusted rate ratio 0.93 , 95 % confidence interval 0.68 to 1.29 ; P=0.68 ) , or referral to the outpatient clinic for moderate morbidity  . Vitamin D supplementation result ed in better vitamin D status as assessed by plasma calcidiol levels at six months . In adjusted analyses , vitamin D treatment significantly increased st and ard deviation ( z ) scores at six months for weight , length , and arm circumference and decreased the proportion of children with stunted growth ( length for age z score ≤2 ) or with arm circumference z scores of 2 or less . Conclusion A weekly dose of vitamin D result ed in better vitamin D status and benefited the classic vitamin D function of bone growth but did not decrease the incidence of severe morbidity or death among young low birthweight infants . Trial registration Clinical Trials.gov NCT00415402 Background Low serum levels of 25-hydroxyvitamin D3 are associated with an increased risk of respiratory tract infections ( RTIs ) . Clinical trials with vitamin D3 against various infections have been carried out but data are so far not conclusive . Thus , there is a need for additional r and omised controlled trials of effects of vitamin D3 on infections . Objective To investigate if supplementation with vitamin D3 could reduce infectious symptoms and antibiotic consumption among patients with antibody deficiency or frequent RTIs . Design A double-blind r and omised controlled trial . Setting Karolinska University Hospital , Huddinge . Participants 140 patients with antibody deficiency ( selective IgA subclass deficiency , IgG subclass deficiency , common variable immune disorder ) and patients with increased susceptibility to RTIs ( > 4 bacterial RTIs/year ) but without immunological diagnosis . Intervention Vitamin D3 ( 4000 IU ) or placebo was given daily for 1 year . Primary and secondary outcome measures The primary endpoint was an infectious score based on five parameters : symptoms from respiratory tract , ears and sinuses , malaise and antibiotic consumption . Secondary endpoints were serum levels of 25-hydroxyvitamin D3 , microbiological findings and levels of antimicrobial peptides ( LL-37 , HNP1–3 ) in nasal fluid . Results The overall infectious score was significantly reduced for patients allocated to the vitamin D group ( 202 points ) compared with the placebo group ( 249 points ; adjusted relative score 0.771 , 95 % CI 0.604 to 0.985 , p=0.04 ) . Limitations A single study centre , small sample size and a selected group of patients . The sample size calculation was performed using p=0.02 as the significance level whereas the primary and secondary endpoints were analysed using the conventional p=0.05 as the significance level . Conclusions Supplementation with vitamin D3 may reduce disease burden in patients with frequent RTIs OBJECTIVE : Observational studies suggest that serum levels of 25-hydroxyvitamin D ( 25[OH]D ) are inversely associated with acute respiratory infections ( ARIs ) . We hypothesized that vitamin D supplementation of children with vitamin D deficiency would lower the risk of ARIs . METHODS : By using cluster r and omization , classrooms of 744 Mongolian schoolchildren were r and omly assigned to different treatments in winter ( January – March ) . This analysis focused on a subset of 247 children who were assigned to daily ingestion of unfortified regular milk ( control ; n = 104 ) or milk fortified with 300 IU of vitamin D3 ( n = 143 ) . This comparison was double-blinded . The primary outcome was the number of parent-reported ARIs over the past 3 months . RESULTS : At baseline , the median serum 25(OH)D level was 7 ng/mL ( interquartile range : 5–10 ng/mL ) . At the end of the trial , follow-up was 99 % ( n = 244 ) , and the median 25(OH)D levels of children in the control versus vitamin D groups was significantly different ( 7 vs 19 ng/mL ; P < .001 ) . Compared with controls , children receiving vitamin D reported significantly fewer ARIs during the study period ( mean : 0.80 vs 0.45 ; P = .047 ) , with a rate ratio of 0.52 ( 95 % confidence interval : 0.31–0.89 ) . Adjusting for age , gender , and history of wheezing , vitamin D continued to halve the risk of ARI ( rate ratio : 0.50 [ 95 % confidence interval : 0.28–0.88 ] ) . Similar results were found among children either below or above the median 25(OH)D level at baseline ( rate ratio : 0.41 vs 0.57 ; Pinteraction = .27 ) . CONCLUSIONS : Vitamin D supplementation significantly reduced the risk of ARIs in winter among Mongolian children with vitamin D deficiency Aims : To investigate the effects of a 6-month supplementation with calcium and cholecalciferol on biochemical parameters and muscle strength of institutionalized elderly . Methods : This prospect i ve , double-blind , placebo-controlled , r and omized trial included Brazilian institutionalized people ≥60 years of age receiving a 6-month supplementation ( December to May ) of daily calcium plus monthly placebo ( calcium/placebo group ) or daily calcium plus oral cholecalciferol ( 150,000 IU once a month during the first 2 months , followed by 90,000 IU once a month for the last 4 months ; calcium/vitamin D group ) . Fasting blood sample s for 25(OH)D , PTH and calcium determination were collected ( n = 56 ) and muscle tests were performed ( n = 46 ) to measure the strength of hip flexors ( SHF ) and knee extensors ( SKE ) before ( baseline ) and after the 6-month intervention ( 6 months ) . Results : Due to seasonal variations , serum 25(OH)D significantly enhanced in both groups after treatment , but the calcium/vitamin D group had significantly higher 25 (OH)D levels than the calcium/placebo group ( 84 vs. 33 % , respectively ; p < 0.0001 ) . No cases of hypercalcemia were observed . While the calcium/placebo group showed no improvement in SHF and SKE at 6 months ( p = 0.93 and p = 0.61 , respectively ) , SHF was increased in the calcium/vitamin D group by 16.4 % ( p = 0.0001 ) and SKE by 24.6 % ( p = 0.0007 ) . Conclusions : The suggested cholecalciferol supplementation was safe and efficient in enhancing 25(OH)D levels and lower limb muscle strength in the elderly , in the absence of any regular physical exercise practice BACKGROUND To our knowledge , no rigorously design ed clinical trials have evaluated the relation between vitamin D and physician-diagnosed seasonal influenza . OBJECTIVE We investigated the effect of vitamin D supplements on the incidence of  seasonal influenza A in schoolchildren . DESIGN From December 2008 through March 2009 , we conducted a r and omized , double-blind , placebo-controlled trial comparing vitamin D(3 ) supplements ( 1200 IU/d ) with placebo  in schoolchildren . The primary outcome was the incidence of influenza A , diagnosed with influenza antigen testing with a nasopharyngeal swab specimen . RESULTS Influenza A occurred in 18 of 167 ( 10.8 % ) children in the vitamin D(3 ) group compared with 31 of 167 ( 18.6 % ) children in the  placebo  group [ relative risk ( RR ) , 0.58 ; 95 % CI : 0.34 , 0.99 ; P = 0.04 ] . The reduction in influenza A was more prominent in children who had not been taking other vitamin D supplements ( RR : 0.36 ; 95 % CI : 0.17 , 0.79 ; P = 0.006 ) and who started nursery school after age 3 y ( RR : 0.36 ; 95 % CI : 0.17 , 0.78 ; P = 0.005 ) . In children with a previous diagnosis of asthma , asthma attacks as a secondary outcome occurred in 2 children receiving vitamin D(3 ) compared with 12 children receiving placebo ( RR : 0.17 ; 95 % CI : 0.04 , 0.73 ; P = 0.006 ) . CONCLUSION This study suggests that vitamin D(3 ) supplementation during the winter may reduce the incidence of influenza A , especially in specific subgroups of schoolchildren . This trial was registered at https://center.umin.ac.jp as UMIN000001373 Calcidiol , the major circulating metabolite of vitamin D , supports induction of pleiotropic antimicrobial responses in vitro . Vitamin D supplementation elevates circulating calcidiol concentrations , and thus has a potential role in the prevention and treatment of infection . The immunomodulatory effects of administering vitamin D to humans with an infectious disease have not previously been reported . To characterize these effects , we conducted a detailed longitudinal study of circulating and antigen-stimulated immune responses in ninety-five patients receiving antimicrobial therapy for pulmonary tuberculosis who were r and omized to receive adjunctive high-dose vitamin D or placebo in a clinical trial , and who fulfilled criteria for per- protocol analysis . Vitamin D supplementation accelerated sputum smear conversion and enhanced treatment-induced resolution of lymphopaenia , monocytosis , hypercytokinaemia , and hyperchemokinaemia . Administration of vitamin D also suppressed antigen-stimulated proinflammatory cytokine responses , but attenuated the suppressive effect of antimicrobial therapy on antigen-stimulated secretion of IL-4 , CC chemokine lig and 5 , and IFN-α . We demonstrate a previously unappreciated role for vitamin D supplementation in accelerating resolution of inflammatory responses during 
    Output:
    
agent
INTERPRETATION Results indicate that vitamin D has a protective effect against RTI , and dosing once-daily seems most effective .
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Low serum 25-hydroxyvitamin D ( 25-[OH]D ) levels have been associated with lower FEV(1 ) , impaired immunologic control , and increased airway inflammation . Because many patients with chronic obstructive pulmonary disease ( COPD ) have vitamin D deficiency , effects of vitamin D supplementation may extend beyond preventing osteoporosis . OBJECTIVE To explore whether supplementation with high doses of vitamin D could reduce the incidence of COPD exacerbations . DESIGN R and omized , single-center , double-blind , placebo-controlled trial . ( Clinical Trials.gov registration number : NCT00666367 ) SETTING University Hospitals Leuven , Leuven , Belgium . PATIENTS 182 patients with moderate to very severe COPD and a history of recent exacerbations . INTERVENTION 100,000 IU of vitamin D supplementation or placebo every 4 weeks for 1 year . MEASUREMENTS The primary outcome was time to first exacerbation . Secondary outcomes were exacerbation rate , time to first hospitalization , time to second exacerbation , FEV(1 ) , quality of life , and death . RESULTS Mean serum 25-(OH)D levels increased significantly in the vitamin D group compared with the placebo group ( mean between-group difference , 30 ng/mL [ 95 % CI , 27 to 33 ng/mL ] ; P < 0.001 ) . The median time to first exacerbation did not significantly differ between the groups ( hazard ratio , 1.1 [ CI , 0.82 to 1.56 ] ; P = 0.41 ) , nor did exacerbation rates , FEV(1 ) , hospitalization , quality of life , and death . However , a post hoc analysis in 30 participants with severe vitamin D deficiency ( serum 25-[OH]D levels < 10 ng/mL ) at baseline showed a significant reduction in exacerbations in the vitamin D group ( rate ratio , 0.57 [ CI , 0.33 to 0.98 ] ; P = 0.042 ) . LIMITATION This was a single-center study with a small sample size . CONCLUSION High-dose vitamin D supplementation in a sample of patients with COPD did not reduce the incidence of exacerbations . In participants with severe vitamin D deficiency at baseline , supplementation may reduce exacerbations . PRIMARY FUNDING SOURCE Applied Biomedical Research Program , Agency for Innovation by Science and Technology ( IWT-TBM ) Objective To investigate whether vitamin D supplementation can decrease the mortality and morbidity of low birthweight infants in low income countries . Design R and omised controlled trial . Setting Large government hospital in New Delhi , India . Participants 2079 low birthweight infants born at term ( > 37 weeks ’ gestation ) . Main outcome measures Primary outcome was admission to hospital or death during the first six months of life . Main secondary outcome was growth . Interventions Weekly vitamin D supplements for six months at a dose of one recommended nutrient intake per day ( 35 µg/week ) . Infants were visited weekly at home for observed supplementation and were brought to the clinic monthly for clinical examination and anthropometric measurements . Results Between group differences were not significant for death or hospital admissions ( 92 among 1039 infants in the vitamin D group v 99 among 1040 infants in the placebo group ; adjusted rate ratio 0.93 , 95 % confidence interval 0.68 to 1.29 ; P=0.68 ) , or referral to the outpatient clinic for moderate morbidity  . Vitamin D supplementation result ed in better vitamin D status as assessed by plasma calcidiol levels at six months . In adjusted analyses , vitamin D treatment significantly increased st and ard deviation ( z ) scores at six months for weight , length , and arm circumference and decreased the proportion of children with stunted growth ( length for age z score ≤2 ) or with arm circumference z scores of 2 or less . Conclusion A weekly dose of vitamin D result ed in better vitamin D status and benefited the classic vitamin D function of bone growth but did not decrease the incidence of severe morbidity or death among young low birthweight infants . Trial registration Clinical Trials.gov NCT00415402 Background Low serum levels of 25-hydroxyvitamin D3 are associated with an increased risk of respiratory tract infections ( RTIs ) . Clinical trials with vitamin D3 against various infections have been carried out but data are so far not conclusive . Thus , there is a need for additional r and omised controlled trials of effects of vitamin D3 on infections . Objective To investigate if supplementation with vitamin D3 could reduce infectious symptoms and antibiotic consumption among patients with antibody deficiency or frequent RTIs . Design A double-blind r and omised controlled trial . Setting Karolinska University Hospital , Huddinge . Participants 140 patients with antibody deficiency ( selective IgA subclass deficiency , IgG subclass deficiency , common variable immune disorder ) and patients with increased susceptibility to RTIs ( > 4 bacterial RTIs/year ) but without immunological diagnosis . Intervention Vitamin D3 ( 4000 IU ) or placebo was given daily for 1 year . Primary and secondary outcome measures The primary endpoint was an infectious score based on five parameters : symptoms from respiratory tract , ears and sinuses , malaise and antibiotic consumption . Secondary endpoints were serum levels of 25-hydroxyvitamin D3 , microbiological findings and levels of antimicrobial peptides ( LL-37 , HNP1–3 ) in nasal fluid . Results The overall infectious score was significantly reduced for patients allocated to the vitamin D group ( 202 points ) compared with the placebo group ( 249 points ; adjusted relative score 0.771 , 95 % CI 0.604 to 0.985 , p=0.04 ) . Limitations A single study centre , small sample size and a selected group of patients . The sample size calculation was performed using p=0.02 as the significance level whereas the primary and secondary endpoints were analysed using the conventional p=0.05 as the significance level . Conclusions Supplementation with vitamin D3 may reduce disease burden in patients with frequent RTIs OBJECTIVE : Observational studies suggest that serum levels of 25-hydroxyvitamin D ( 25[OH]D ) are inversely associated with acute respiratory infections ( ARIs ) . We hypothesized that vitamin D supplementation of children with vitamin D deficiency would lower the risk of ARIs . METHODS : By using cluster r and omization , classrooms of 744 Mongolian schoolchildren were r and omly assigned to different treatments in winter ( January – March ) . This analysis focused on a subset of 247 children who were assigned to daily ingestion of unfortified regular milk ( control ; n = 104 ) or milk fortified with 300 IU of vitamin D3 ( n = 143 ) . This comparison was double-blinded . The primary outcome was the number of parent-reported ARIs over the past 3 months . RESULTS : At baseline , the median serum 25(OH)D level was 7 ng/mL ( interquartile range : 5–10 ng/mL ) . At the end of the trial , follow-up was 99 % ( n = 244 ) , and the median 25(OH)D levels of children in the control versus vitamin D groups was significantly different ( 7 vs 19 ng/mL ; P < .001 ) . Compared with controls , children receiving vitamin D reported significantly fewer ARIs during the study period ( mean : 0.80 vs 0.45 ; P = .047 ) , with a rate ratio of 0.52 ( 95 % confidence interval : 0.31–0.89 ) . Adjusting for age , gender , and history of wheezing , vitamin D continued to halve the risk of ARI ( rate ratio : 0.50 [ 95 % confidence interval : 0.28–0.88 ] ) . Similar results were found among children either below or above the median 25(OH)D level at baseline ( rate ratio : 0.41 vs 0.57 ; Pinteraction = .27 ) . CONCLUSIONS : Vitamin D supplementation significantly reduced the risk of ARIs in winter among Mongolian children with vitamin D deficiency Aims : To investigate the effects of a 6-month supplementation with calcium and cholecalciferol on biochemical parameters and muscle strength of institutionalized elderly . Methods : This prospect i ve , double-blind , placebo-controlled , r and omized trial included Brazilian institutionalized people ≥60 years of age receiving a 6-month supplementation ( December to May ) of daily calcium plus monthly placebo ( calcium/placebo group ) or daily calcium plus oral cholecalciferol ( 150,000 IU once a month during the first 2 months , followed by 90,000 IU once a month for the last 4 months ; calcium/vitamin D group ) . Fasting blood sample s for 25(OH)D , PTH and calcium determination were collected ( n = 56 ) and muscle tests were performed ( n = 46 ) to measure the strength of hip flexors ( SHF ) and knee extensors ( SKE ) before ( baseline ) and after the 6-month intervention ( 6 months ) . Results : Due to seasonal variations , serum 25(OH)D significantly enhanced in both groups after treatment , but the calcium/vitamin D group had significantly higher 25 (OH)D levels than the calcium/placebo group ( 84 vs. 33 % , respectively ; p < 0.0001 ) . No cases of hypercalcemia were observed . While the calcium/placebo group showed no improvement in SHF and SKE at 6 months ( p = 0.93 and p = 0.61 , respectively ) , SHF was increased in the calcium/vitamin D group by 16.4 % ( p = 0.0001 ) and SKE by 24.6 % ( p = 0.0007 ) . Conclusions : The suggested cholecalciferol supplementation was safe and efficient in enhancing 25(OH)D levels and lower limb muscle strength in the elderly , in the absence of any regular physical exercise practice BACKGROUND To our knowledge , no rigorously design ed clinical trials have evaluated the relation between vitamin D and physician-diagnosed seasonal influenza . OBJECTIVE We investigated the effect of vitamin D supplements on the incidence of  seasonal influenza A in schoolchildren . DESIGN From December 2008 through March 2009 , we conducted a r and omized , double-blind , placebo-controlled trial comparing vitamin D(3 ) supplements ( 1200 IU/d ) with placebo  in schoolchildren . The primary outcome was the incidence of influenza A , diagnosed with influenza antigen testing with a nasopharyngeal swab specimen . RESULTS Influenza A occurred in 18 of 167 ( 10.8 % ) children in the vitamin D(3 ) group compared with 31 of 167 ( 18.6 % ) children in the  placebo  group [ relative risk ( RR ) , 0.58 ; 95 % CI : 0.34 , 0.99 ; P = 0.04 ] . The reduction in influenza A was more prominent in children who had not been taking other vitamin D supplements ( RR : 0.36 ; 95 % CI : 0.17 , 0.79 ; P = 0.006 ) and who started nursery school after age 3 y ( RR : 0.36 ; 95 % CI : 0.17 , 0.78 ; P = 0.005 ) . In children with a previous diagnosis of asthma , asthma attacks as a secondary outcome occurred in 2 children receiving vitamin D(3 ) compared with 12 children receiving placebo ( RR : 0.17 ; 95 % CI : 0.04 , 0.73 ; P = 0.006 ) . CONCLUSION This study suggests that vitamin D(3 ) supplementation during the winter may reduce the incidence of influenza A , especially in specific subgroups of schoolchildren . This trial was registered at https://center.umin.ac.jp as UMIN000001373 Calcidiol , the major circulating metabolite of vitamin D , supports induction of pleiotropic antimicrobial responses in vitro . Vitamin D supplementation elevates circulating calcidiol concentrations , and thus has a potential role in the prevention and treatment of infection . The immunomodulatory effects of administering vitamin D to humans with an infectious disease have not previously been reported . To characterize these effects , we conducted a detailed longitudinal study of circulating and antigen-stimulated immune responses in ninety-five patients receiving antimicrobial therapy for pulmonary tuberculosis who were r and omized to receive adjunctive high-dose vitamin D or placebo in a clinical trial , and who fulfilled criteria for per- protocol analysis . Vitamin D supplementation accelerated sputum smear conversion and enhanced treatment-induced resolution of lymphopaenia , monocytosis , hypercytokinaemia , and hyperchemokinaemia . Administration of vitamin D also suppressed antigen-stimulated proinflammatory cytokine responses , but attenuated the suppressive effect of antimicrobial therapy on antigen-stimulated secretion of IL-4 , CC chemokine lig and 5 , and IFN-α . We demonstrate a previously unappreciated role for vitamin D supplementation in accelerating resolution of inflammatory responses during 
    Output:
    