***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: Effects of nutritional supplements on minimizing weight loss and abnormalities of protein turnover during pulmonary exacerbations in cystic fibrosis ( CF ) were studied by controlled trial . Patients received pulmonary therapy and either st and ard diet ( n = 10 ) or adjunctive enteral supplements ( n = 12 ) . Initial protein turnover , measured by [15N]glycine kinetics , showed alterations of protein synthesis ( P Syn ) and catabolism ( P Cat ) , which correlated with the degree of underweight , and negligible net protein deposition ( P Dep ) . With treatment both groups had significant increases in mean body weight and forced expiratory volume in 1 s , expressed as percent predicted value for height ( FEV1 ) by 3 wk , but a significant correlation between initial underweight and subsequent weight gain was observed only in supplemented patients . Mean P Syn and P Dep increased significantly ( p less than 0.001 ) only in the supplemented group . Pulmonary exacerbations in CF have important adverse effects on body-protein metabolism , similar to changes in protein-energy malnutrition and infection . These effects are reversed by short-term nutritional support . Strategic nutritional intervention should thus be considered in management , especially in malnourished patients BACKGROUND Stunted children with cystic fibrosis ( CF ) have less net protein anabolism than do children without CF , and the result is retarded growth in the CF patients . It is not known whether protein intake above that recommended by the Cystic Fibrosis Foundation would further stimulate whole-body protein synthesis . OBJECTIVE We studied the effects of 3 amounts of protein intake on whole-body protein synthesis and breakdown by using isotopic infusion of [1-(13)C]valine and [(15)N(2)]urea in children with stable CF who required tube feeding . DESIGN In 8 pediatric CF patients , we administered 3 r and omly allocated isocaloric diets with normal ( NP ) , intermediate ( IP ) , and high ( HP ) amounts of protein ( 1.5 , 3 , and 5 g . kg(-1 ) . d(-1 ) , respectively ) by continuous drip feeding during a 4-d period at 6-wk intervals . Each patient acted as his or her own control . On the fourth day of feeding , whole-body protein synthesis and breakdown were measured . RESULTS Protein synthesis was significantly higher in the HP group ( x + /- SEM : 1.78 + /- 0.07 micromol . kg(-1 ) . min(-1 ) ) than in the IP ( 1.57 + /- 0.08 micromol . kg(-1 ) . min(-1 ) ; P=0.001 ) and NP ( 1.37 + /- 0.07 micromol . kg(-1 ) . min(-1 ) ; P < 0.001 ) groups . There were no significant differences in protein breakdown . Net retention of nitrogen was significantly higher in the HP group ( 12.93 + /- 1.42 micromol . kg(-1 ) . min(-1 ) ) than in the IP ( 7.61 + /- 1.40 micromol . kg(-1 ) . min(-1 ) ; P=0.01 ) and HP ( 2.48 + /- 0.20 micromol . kg(-1 ) . min(-1 ) ; P < 0.001 ) groups . CONCLUSION In stunted children with CF requiring tube feeding , the highest stimulation of whole-body protein synthesis was achieved with a short-term dietary protein intake of 5 g . kg(-1 ) . d(-1 ) Survival in cystic fibrosis has improved significantly in the last 30 years , with major therapeutic goals of delaying the progressive loss of pulmonary function and maintaining normal growth . Dual-energy X-ray absorptiometry ( DEXA ) was performed in children with cystic fibrosis ( CF ) to assess both bone mineral density and body composition . We hypothesised that there would be an association between body composition and pulmonary function in children with CF . Fifty subjects with CF ( 28 males ) , mean age 12.7 years , participated in the study .  Body composition was determined by DEXA .  Body mass index ( BMI ) was calculated from the ratio of weight/height2 ( kg/m2 ) . Lung function was assessed by spirometry . Most patients ( 78 % ) had mild lung disease  . The mean forced expired volume in 1 sec percent predicted ( FEV1 % predicted ) for the 50 patients was 79.2 % ( range , 24 - 117 % ) . There was a strong association between FEV1 % predicted and BMI ( R=0.59 , P=0.0001 ) . Fat-free mass had positive association with pulmonary function tests ( R=0.30 , P=0.03 ) . Although fat mass showed a positive correlation with pulmonary function , this association did not reach statistical significance . In our group of children with CF and mild lung disease , pulmonary function was more strongly associated with BMI than with fat and fat-free mass High fat containing diets lower VCO(2)in  patients with impaired pulmonary function fed at a high level of energy intake . We tested the effect of a high fat enteral nutrition on VCO(2 ) and substrate oxidation in cystic fibrosis patients fed enterally 130 % RDA .  VCO(2 ) and substrate oxidation were studied in a group of eight 6 - 19 year old patients while receiving for 1 month and in a r and om order isocaloric ( 1000 kcal/m(2 ) ) , isonitrogenous enteral diet with a normal fat and a high fat content  ( 40 % and 67 % of non-protein energy intake ) . Substrate oxidation and net balance were estimated using indirect calorimetry at the end of each study period . Overnight high fat enteral infusion result ed in no significant change in VCO(2 ) and VO(2)but lowered RQ ( 0.84 + /- 0.01 vs 0.88 + /- 0.01 , P= 0.02 ) and non-protein RQ ( 0.83 + /- 0.01 vs 0.88 + /- 0.01 ) . In spite of a higher glucose oxidation rate ( 8.1 + /- 0.5 vs 6.3 + /- 0.5 g. h(-1 ) , P= 0.04 ) , glucose net balance was significantly higher during normal fat formula administration ( + 2.5 + /- 0.8 v -0.3 7plusmn ; 0.7 g/h , P < 0.05 ) . The present study failed to show any benefit of a high fat diet on VCO(2)in non oxygenodependant cystic fibrosis children and adolescents fed slightly above RAD . Normal fat enteral formula led to higher glycogen repletion OBJECTIVE To determine whether differences in tolerance and absorption of fat and nitrogen exist between a semi-elemental nutritional formula without enzyme replacement and a nonelemental formula with enzyme replacement . STUDY DESIGN Sixteen patients ( eight girls and eight boys ) with cystic fibrosis , 4 to 20 years of age ( 12+/-1.3 , mean + /- SEM ) , who were pancreatic insufficient completed two 6-day regimens of nocturnal continuous enteral feedings offered in r and om order . Forty-four percent of the total daily energy was consumed as enteral tube feedings , and the remaining oral dietary intake remained constant throughout the study . Seventy-two-hour fecal collection s from each study period were analyzed for total fat , long-chain fatty acids ( LCFAs ) , medium-chain fatty acids ( MCFAs ) , and nitrogen . RESULTS Fat absorption was 80.2%+/-2.9 % and 82.3%+/-3.1 % ( p = 0.58 ) for the semi-elemental and nonelemental formulas , respectively . Similarly , the coefficient of absorption of LCFAs was 69.5%+/-4.5 % and 79.6%+/-3.4 % ( p = 0.30 ) for the semi-elemental and nonelemental formulas . Malabsorption of MCFAs contributed minimally to total fat malabsorption . There was no difference between formulas for MCFA or for nitrogen absorption , 83.7%+/-1.9 % and 87.4%+/-1.4 % , p = 0.48 . All patients tolerated all feedings , and weight gained was 1.8+/-0.3 kg with no difference in weight gain between the trials . CONCLUSION A nonelemental formula , with enzyme replacement , is absorbed as well as a predigested formula in patients with CF who are pancreatic insufficient BACKGROUND There is currently a lack of clinical data on fibre requirements in UK children . Subsequently , the ideal fibre profile for enteral formulae design ed to meet the requirements of older children is unknown . The present study aim ed to investigate the effect of fibre supplementation on gastrointestinal function of children aged 7 - 12 years ( or weight 21 - 45 kg ) receiving an age-specific high-energy enteral feed . METHODS In this double-blind r and omised crossover study , 25 home enterally tube-fed children with a range of medical conditions ( including cystic fibrosis , neurological conditions , liver transplant and bone marrow transplant ) were given a 1.5 kcal mL(-1 ) formula with or without added dietary fibre ( 1.13 g per 100 mL ) . Each formula was taken for 6 weeks , followed by 6 months on the second r and omly assigned formula . Anthropometry , blood biochemistry , stool characteristics , tolerance and oral dietary intake were assessed . RESULTS Despite a higher median fibre intake on the fibre-containing formula ( 84 % versus 26 % of recommended intake ; P = 0.003 ) , most children did not meet existing international recommendations for fibre as a result of small feed volumes ( median 800 mL day(-1 ) ; 9 g fibre day(-1 ) ) . There was some evidence of reduced constipation , laxative reliance and abdominal pain on the fibre-containing formula . CONCLUSIONS Given the poor fibre intakes and absence of adverse effects , the use of fibre-containing formulae should become st and ard practice for the majority of children on enteral feeds . Larger trials in children are required to further evaluate the effect of amount and blend of fibre in enteral formulae for older children . However , it is likely that current formulae require higher levels of fibre This study examined whether the increase in CO2 production ( VCO2 ) and ventilatory dem and s by carbohydrate loading with different formulas during nighttime enteral feedings could be detrimental in young adult cystic fibrosis patients with moderate to advanced lung disease . Ten patients age 17 to 24 ( mean 21.4 years ) received 1000 kcal/M2 of a low ( Pulmocare ) , medium ( Ensure Plus ) , and high ( Vivonex HN ) carbohydrate formula in r and om order .  Eight patients had severe , and two moderate obstructive pulmonary disease ; nine used  nighttime oxygen therapy .  Basal energy expenditure ( BEE ) without feedings averaged 120 % of that predicted by the Harris-Benedict equation . The metabolic expenditure by indirect calorimetry during nighttime feedings was 25 to 36 % greater than the BEE . Oxygen consumption ( VO2 ) increased 21 to 27 % during nighttime feedings with no difference between formulas . VCO2 increased 29 % for Pulmocare , 46 % with Ensure Plus , and 53 % with Vivonex HN . The increase in VCO2 with Pulmocare was significantly less than Ensure Plus ( p less than 0.05 ) and Vivonex HN ( p less than 0.005 ) . The respiratory quotient ( RQ ) ( VCO2-/VO2 ) for Pulmocare ( 0.88 ) was the same as the BEE , but increased with Ensure Plus ( 1.00 ) , and Vivonex HN ( 1.08 ) . The 41 % increase in minute ventilation with Vivonex HN was greater than the 25 to 28 % increase observed for Pulmocare and Ensure Plus ( p less than 0.05 ) . Transcutaneous oxygen saturation fell no more than 2 % with all formulas . PCO2 changed + /- 5 torr during enteral feedings with similar changes in any patient with all formulas . ( ABSTRACT TRUNCATED AT 250 WORDS Background Patients with cystic fibrosis who have steatorrhea frequently are underweight and have essential fatty acid ( EFA ) depletion , which is associated with a poor clinical course . It has been stated that poor EFA status is difficult to correct in patients with cystic fibrosis , and an impaired EFA metabolism with reduced synthesis of long-chain polyunsaturated fatty acids has been proposed . In this study , the effects of an oral energy supplement rich in linoleic acid were investigated in patients with cystic fibrosis who had a body weight below 95 % of normal for height . Methods Thirty-six patients ( 16 girls ) more than 4 years of age were r and omized either to a control group ( n = 20 , age 13.3 ± 3.8 years , mean ± SD ) receiving intensive dietary counseling only , or an intervention group ( n = 16 , age , 10.4 ± 4.3 years ) treated for 3 months with dietary counseling plus 628 ± 254 mL ( = kcal ) per day of an energy supplement rich in fat ( 31 % of energy ) and linoleic acid ( 16 % of energy ) . Results In contrast to 
    Output:
    
Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis .
The methods mostly used , nasogastric or gastrostomy feeding , are expensive and may have a negative effect on self-esteem and body image .
It is acknowledged , however , that performing a r and omised controlled trial would be difficult due to the ethics of withholding an intervention in a group of people whose nutritional status necessitates it