***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 
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    Input: The inflammatory cytokines , tumor necrosis factor-alpha ( TNF-alpha ) and interleukin-1-beta ( IL-1 beta ) , have been associated with accelerated metabolism and protein turnover following exogenous administration in normal humans . We hypothesized that these inflammatory cytokines might contribute to the weight-losing process in patients with chronic obstructive pulmonary disease ( COPD ) . COPD patients were identified prospect ively as " weight losers " ( WL ; n = 10 ) if they reported > 5 % weight loss during the preceding year or as " weight stable " ( WS ; n = 10 ) if their body weight fluctuated < or = 5 % . Age-matched healthy volunteers were selected as the control group ( C ; n = 13 ) . Monocytes were isolated from a peripheral blood sample , cultured , and exposed to lipopolysaccharide ( LPS ) . The concentration of TNF-alpha and IL-1 beta in the monocyte supernatant was measured using a four layer enhanced ELISA . No significant difference in LPS-stimulated IL-1 beta production was found in the three study population s. However , LPS-stimulated TNF-alpha production ( mean [ range ] ng/ml ) by monocytes was significantly higher in the WL COPD patients ( 20.2 [ 6.3 to 44.8 ] ) , compared with WS patients ( 6.9 [ 1.5 to 16.6 ] ) , and C subjects ( 5.7 [ 0 to 61.8 ] ) . This difference was not maintained at 6 mo follow-up in the absence of ongoing weight loss . Definition of a causal relationship between TNF-alpha production and weight loss will require further underst and ing of the relationship between energy metabolism and TNF-alpha production in these patients The relation between vitamin A status and the degree of lung airway obstruction was examined in a cross-sectional study of 36 male subjects aged 43 - 74 y who were assigned to five groups as follows : healthy nonsmokers ( n = 7 ) , healthy smokers ( n = 7 ) , mild chronic obstructive pulmonary disease ( COPD -mild ) patients ( n = 9 ) , COPD -moderate-severe patients ( n = 7 ) , and COPD -moderate-severe patients with exacerbation ( + ex ; n = 6 ) .  Smoking habits , pulmonary function tests , energy-protein status were assessed ; serum concentrations of retinyl esters , retinol , retinol binding protein , and transthyretin and relative dose responses were measured . In addition , 12 male smokers aged 45 - 61 y with mild COPD were r and omly assigned to two groups for a longitudinal study : six subjects consumed vitamin A ( 1000 RE/d ; COPD -vitamin A ) and six subjects received placebo for 30 d. Lowered serum retinol concentrations were found in the COPD -moderate-severe and COPD -moderate-severe+ex groups . Measurements of vitamin A status in healthy smokers and in COPD -mild patients were not different from those in healthy nonsmokers . The improvement of pulmonary function test results after vitamin A supplementation [ mean increase for 1-s forced expiratory volume ( FEV1 ) = 22.9 % in the COPD -vitamin A group ] may support the assumption of a local ( respiratory ) vitamin A deficiency in patients with this disease STUDY OBJECTIVE Weight loss is a common complication of COPD , associated with negative outcomes . Weight restoration has been associated with improved outcomes . The effects of ox and rolone , an adjunct to help restore weight , were evaluated in patients with COPD . DESIGN Prospect i ve , open-label , 4-month clinical trial . SETTING Twenty-five community-based pulmonary practice s throughout the United States . PATIENTS A primary pulmonary diagnosis of moderate-to-severe COPD as defined by FEV1 < 50 % of predicted and FEV1/FVC ratio < 0.7 , along with significant involuntary weight loss ( weight < or = 90 % ideal body weight ) . INTERVENTIONS Oral ox and rolone , 10 mg bid . MEASUREMENTS AND RESULTS Body weight , body composition ( bioelectric impedance analysis ) , spirometry , and 6-min walking distance were measured . Data for 82 patients at 2 months and 55 patients at 4 months are presented . At month 2 , 88 % of patients had gained a mean + /- SD of 6.0 + /- 4.36 lb ( p < 0.05 ) and 12 % had lost a mean of 1.7 + /- 2.15 lb ( not statistically significant [ NS ] ) . At month 4 , 84 % had gained a mean of 6.0 + /- 5.83 lb ( p < 0.05 ) and 16 % had lost a mean of 1.8 + /- 1.74 lb ( NS ) . Month 4 bioelectric impedance analysis showed the weight to be primarily lean tissue , with a mean increase in body cell mass of 3 + /- 2.6 lb ( p < 0.05 ) , and a mean increase in fat of 1.2 + /- 4.6 lb ( NS ) . CONCLUSIONS Ox and rolone is an effective adjunct to facilitate weight restoration in patients with COPD -associated weight loss . Weight gain is primarily lean body mass . Ox and rolone was relatively well tolerated and , therefore , should be a consideration in the comprehensive management of patients with COPD and weight loss The effects of adding L-carnitine to a whole-body and respiratory training program were determined in moderate-to-severe chronic obstructive pulmonary disease ( COPD ) patients . Sixteen COPD patients ( 66 + /- 7 years ) were r and omly assigned to L-carnitine ( CG ) or placebo group ( PG ) that received either L-carnitine or saline solution ( 2 g/day , orally ) for 6 weeks ( forced expiratory volume on first second was 38 + /- 16 and 36 + /- 12 % , respectively ) . Both groups participated in three weekly 30-min treadmill and threshold inspiratory muscle training sessions , with 3 sets of 10 loaded inspirations ( 40 % ) at maximal inspiratory pressure . Nutritional status , exercise tolerance on a treadmill and six-minute walking test , blood lactate , heart rate , blood pressure , and respiratory muscle strength were determined as baseline and on day 42 . Maximal capacity in the incremental exercise test was significantly improved in both groups ( P < 0.05 ) . Blood lactate , blood pressure , oxygen saturation , and heart rate at identical exercise levels were lower in CG after training ( P < 0.05 ) . Inspiratory muscle strength and walking test tolerance were significantly improved in both groups , but the gains of CG were significantly higher than those of PG ( 40 + /- 14 vs 14 + /- 5 cmH2O , and 87 + /- 30 vs 34 + /- 29 m , respectively ; P < 0.05 ) . Blood lactate concentration was significantly lower in CG than in PG ( 1.6 + /- 0.7 vs 2.3 + /- 0.7 mM , P < 0.05 ) . The present data suggest that carnitine can improve exercise tolerance and inspiratory muscle strength in COPD patients , as well as reduce lactate production The impact of oral nutritional supplementation during an acute exacerbation of COPD on functional status was assessed through measuring change in lung function , strength testing , and general well-being .  Subjects hospitalized for an acute exacerbation of COPD ( n = 33 ) were r and omized to extra nutritional support or the regular hospital care . They consumed an additional 10 kcal/kg/d . Outcome measures were measured at 2 wk as change scores . Forced vital capacity ( % predicted ) improved in the treatment group as compared with the control group ( + 8.7 % versus -3.5 % , p = 0.015 ) , and change in FEV1 was in the same direction but not significantly different ( p = 0.099 ) . There were no changes in h and grip strength or respiratory muscle strength , but there was a trend towards more improvement in the general well-being score ( + 11.96 versus -10.25 , p = 0.066 ) . Almost all subjects were in negative nitrogen balance , indicating muscle wasting . The degree of muscle wasting was strongly correlated with the dose of corticosteroids ( r = 0.73 , p < 0.005 ) . In conclusion , it is difficult to prevent important muscle wasting in patients with COPD treated with corticosteroids , but some small gains were observed with increased dietary intake Nutritional depletion commonly occurs in patients with COPD , causing muscle wasting and impaired physiologic function . Two hundred seventeen patients with COPD participated in a placebo-controlled , r and omized trial investigating the physiologic effects of nutritional intervention alone ( N ) for 8 wk or combined with the anabolic steroid n and rolone decanoate ( N + A ) . N and rolone decanoate or placebo ( P ) was injected intramuscularly ( women , 25 mg ; men , 50 mg ) in a double-blind fashion on Days 1 , 15 , 29 , and 43 . Nutritional intervention consisted of a daily high caloric supplement ( 420 kcal ; 200 ml ) . Also , all patients participated in an exercise program . In the depleted patients , both treatment regimens induced a similar significant body weight gain ( 2.6 kg ) but different body compositional changes . Particularly in the last 4 wk of treatment , weight gain in the N group was predominantly due to an expansion of fat mass ( p < 0.03 versus P and N + A ) , whereas the relative changes in fat-free mass ( FFM ) and other measures of muscle mass were more favorable in the N + A group ( p < 0.03 versus P ) . Maximal inspiratory mouth pressure improved within both treatment groups in the first 4 wk of treatment , but after 8 wk only N + A was significantly different from P ( p < 0.03 ) . Nutritional supplementation in combination with a short course of anabolic steroids may enhance the gain in FFM and respiratory muscle function in depleted patients with COPD without causing adverse side effects Background : Pulmonary rehabilitation is effective in improving exercise performance and health status in chronic obstructive pulmonary disease ( COPD ) . However , the role of nutritional support in the enhancement of the benefits of exercise training has not been explored . A double blind , r and omised , controlled trial of carbohydrate supplementation was undertaken in patients attending outpatient pulmonary rehabilitation . Methods : 85 patients with COPD were r and omised to receive a 570 kcal carbohydrate rich supplement or a non-nutritive placebo daily for the duration of a 7 week outpatient pulmonary rehabilitation programme . Primary outcome measures were peak and submaximal exercise performance using the shuttle walk tests . Changes in health status , body composition , muscle strength , and dietary macronutrient intake were also measured . Results : Patients in both the supplement and placebo groups increased shuttle walking performance and health status significantly . There was no statistically significant difference between treatment groups in these outcomes . Patients receiving placebo lost weight whereas supplemented patients gained weight . In well nourished patients ( BMI > 19 kg/m2 ) improvement in incremental shuttle performance was significantly greater in the supplemented group ( mean difference between groups : 27 ( 95 % CI 1 to 53 ) m , p<0.05 ) . Increases in incremental shuttle performance correlated with increases in total carbohydrate intake . Conclusions : When universally prescribed , carbohydrate supplementation does not enhance the rehabilitation of patients with COPD . This study suggests that exercise training results in negative energy balance that can be overcome by supplementation and that , in selected patients , this may improve the outcome of training . The finding of benefit in well nourished patients may suggest a role for nutritional supplementation beyond the treatment of weight loss in COPD Unexplained weight loss is common in chronic obstructive pulmonary disease ( COPD ) . Blood levels of tumor necrosis factor-alpha ( TNF-alpha ) , a cytokine causing cachexia in laboratory animals , are elevated in various human diseases associated with weight loss . We therefore prospect ively measured TNF-alpha serum levels ( immunoradiometric assay ) in patients with clinical ly stable COPD ( n = 30 ; all male ; mean age , 65 yr ) whose weight was less ( Group I ; n = 16 ) or more ( Group II ; n = 14 ) than the lower limit of normal taken from Metropolitan Life Insurance Company tables . The patients had no cause known to elevate TNF-alpha serum levels ; notably , they were not infected . Group I patients had unintentionally lost weight during the previous year , whereas the weight of Group II patients had not changed during the same period . The two groups had similar chronic airflow obstruction and arterial blood gas impairment ; hyperinflation and reduction in diffusing capacity were more pronounced in Group I , but differences were not significant . TNF-alpha serum levels ( pg/ml ; mean [ SD ] ) were significantly higher in Group I than in Group II ( 70.2 [ 100.0 ] versus 6.7 [ 6.4 ] ; p < 0.001 ) . Group II TNF-alpha serum levels did not differ significantly from those of healthy subjects ( 7.8 [ 3.9 ] ) , whereas those of Group I were significantly higher ( p < 0.001 ) . Because renal function was in the normal range , we 
    Output:
    
Nutritional support had no significant effect on anthropometric measures , lung function or exercise capacity in patients with stable COPD