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: Tissue levels of n-3 fatty acids reflect dietary intake , but quantitative data about rate of incorporation and levels as a function of intake are scarce . We fed 58 men 0 , 3 , 6 , or 9 g/d of fish oil for 12 months and monitored fatty acids in serum cholesteryl esters , erythrocytes , and subcutaneous fat during and after supplementation .  Eicosapentaenoic acid ( EPA ) in cholesteryl esters plateaued after 4 - 8 weeks ; the incorporation half-life was 4.8 days . Steady-state levels increased by 3.9 + /- 0.3 mass % points ( + /- SE ) for each extra gram of EPA eaten per day . Incorporation of docosahexaenoic acid ( DHA ) was erratic ; plateau values were 1.1 + /- 0.1 mass % higher for every g/d ingested . Incorporation of EPA into erythrocyte membranes showed a half-life of 28 days ; a steady state was reached after 180 days . Each g/d increased levels by 2.1 + /- 0.1 mass % . C22:5n-3 levels increased markedly . Changes in DHA were erratic and smaller . EPA levels in adipose tissue rose also ; the change after 6 months was 67 % of that after 12 months in gluteal and 75 % in abdominal fat . After 12 months each gram per day caused an 0.11 + /- 0.01 mass % rise in gluteal fat for EPA , 0.53 + /- 0.07 for C22:5n-3 , and 0.14 + /- 0.03 for DHA . Thus , different ( n-3 ) fatty acids were incorporated with different efficiencies , possibly because of interconversions or different affinities of the enzymatic pathways involved . EPA levels in cholesteryl esters reflect intake over the past week or two , erythrocytes over the past month or two , and adipose tissue over a period of years . These findings may help in assessing the intake of ( n-3 ) fatty acids in epidemiological studies BACKGROUND Fish and seafood n-3 fatty acids may prevent or delay the progression of prostate cancer , but epidemiologic studies do not uniformly support this hypothesis . OBJECTIVE We examined the relation of fish and seafood n-3 fatty acid intakes with  prostate cancer incidence and mortality . DESIGN We conducted a prospect i ve cohort study among 20,167 men participating in the Physician 's Health Study who were free of cancer in 1983 . RESULTS During 382 144 person-years of follow-up , 2161 men were diagnosed with prostate cancer and 230 died of prostate cancer . Fish intake was unrelated to prostate cancer incidence . Survival analysis among the men diagnosed with prostate cancer revealed that those consuming fish > or=5 times/wk had a 48 % lower risk of prostate cancer death than did men consuming fish less than once weekly [ relative risk ( RR ) = 0.52 ; 95 % CI : 0.30 , 0.91 ; P for trend = 0.05 ] . A similar association was found between seafood n-3 fatty acid intake and prostate cancer mortality ( RR(Q5 versus Q1 ) = 0.64 ; 95 % CI : 0.42 , 0.99 ; P for trend = 0.02 ) . These associations became stronger when the analyses were restricted to clinical ly detected cases . CONCLUSION These results suggest that fish intake is unrelated to prostate cancer incidence but may improve prostate cancer survival Systematic review s ( SRs ) are an increasingly popular evidence -based tool and are often used to answer complex research questions across many different research domains . Early SR methodology was advanced by social scientists , and the term meta- analysis was coined by a social scientist who also conducted research in psychology . SRs have recently become popular in healthcare and are likely to be beneficial in any field . The aim of this report is to highlight issues in SR conduct with a focus on the field of nutrition and to make recommendations on improving SR conduct in this area . Development of the research question is probably the most important step in conducting an SR . The 4 main components of an answerable question are 1 ) the patient , population , or problem ; 2 ) the intervention , independent variable , or exposure ; 3 ) the comparators ; and 4 ) the dependent variables or outcomes of interest . The question will be used to determine the optimal methods for conducting the SR . SRs often include study design s beyond r and omized trials and do not always include a meta- analysis of the results . Other topics explored include underst and ing and interpreting discordant review s and the importance of reporting tools [ eg , QUality Of Reporting Of Meta-analyses ( QUOROM Statement ) or CONsoli date d St and ards Of Reporting of Trials ( CONSORT Statement ) ] . Recommendations are then provided , such as developing a capacity-building program , search ing the primary literature for research gaps , and extending reporting tools such as the QUOROM Statement to the field of nutrition BACKGROUND Findings from early observational studies have suggested that the intake of dietary fat might be a contributing factor in the etiology of prostate cancer . However , the results from more recent prospect i ve studies do not support this hypothesis , and the possible association between different food sources of fat and prostate cancer risk also remains unclear . OBJECTIVE The objectives were to assess whether intakes of dietary fat , subtypes of fat , and fat from animal products were associated with prostate cancer risk . DESIGN This was a multicenter prospect i ve study of 142,520 men in the European Prospect i ve Investigation into Cancer and Nutrition ( EPIC ) . Dietary fat intake was estimated with the use of country-specific vali date d food question naires . The association between dietary fat and risk of prostate cancer was assessed by using Cox regression , stratified by recruitment center and adjusted for height , weight , smoking , education , marital status , and energy intake . RESULTS After a median follow-up time of 8.7 y , prostate cancer was diagnosed in 2727 men . There was no significant association between dietary fat ( total , saturated , monounsaturated , and polyunsaturated fat and the ratio of polyunsaturated to saturated fat ) and risk of prostate cancer . The hazard ratio for prostate cancer for the highest versus the lowest quintile of total fat intake was 0.96 ( 95 % CI : 0.84 , 1.09 ; P for trend = 0.155 ) . There were no significant associations between prostate cancer risk and fat from red meat , dairy products , and fish . CONCLUSION The results from this large multicenter study suggest that there is no association between dietary fat and prostate cancer risk BACKGROUND Laboratory studies have shown that n-3 fatty acids inhibit and n-6 fatty acids stimulate prostate tumor growth , but whether the dietary intake of these fatty acids affects prostate cancer risk in humans remains unclear . OBJECTIVE We prospect ively evaluated the association between intakes of alpha-linolenic ( ALA ; 18:3n-3 ) , eicosapentaenoic ( EPA ; 20:5n-3 ) , docosahexaenoic ( DHA ; 22:6n-3 ) , linoleic ( LA ; 18:2n-6 ) , and arachidonic ( AA ; 20:4n-6 ) acids and prostate cancer risk . DESIGN A cohort of 47 866 US men aged 40 - 75 y with no cancer history in 1986 was followed for 14 y. RESULTS During follow-up , 2965 new cases of total prostate cancer were ascertained , 448 of which were advanced prostate cancer . ALA intake was unrelated to the risk of total prostate cancer . In contrast , the multivariate relative risks ( RRs ) of advanced prostate cancer from comparisons of extreme quintiles of ALA from nonanimal sources and ALA from meat and dairy sources were 2.02 ( 95 % CI : 1.35 , 3.03 ) and 1.53 ( 0.88 , 2.66 ) , respectively .  EPA and DHA intakes were related to lower prostate cancer risk . The multivariate RRs of total and advanced prostate cancer from comparisons of extreme quintiles of the combination of EPA and DHA were 0.89 ( 0.77 , 1.04 ) and 0.74 ( 0.49 , 1.08 ) , respectively . LA and AA intakes were unrelated to the risk of prostate cancer . The multivariate RR of advanced prostate cancer from a comparison of extreme quintiles of the ratio of LA to ALA was 0.62 ( 0.45 , 0.86 ) . CONCLUSIONS Increased dietary intakes of ALA may increase the risk of advanced prostate cancer . In contrast , EPA and DHA intakes may reduce the risk of total and advanced prostate cancer Background : Estimation of the intake of oily fish at a population level is difficult . The measurement of eicosapentaenoic acid ( EPA ) and docosahexaenoic acid ( DHA ) in biological sample s may provide a useful biomarker of intake . Objective : We identified the most appropriate biomarkers for the assessment of habitual oily fish intake and changes in intake by elucidating the dose- and time-dependent response of EPA and DHA incorporation into various biological sample s that represent roles in fatty acid transport , function , and storage . Design : This was a double-blind , r and omized , controlled intervention trial in 204 men and women that lasted 12 mo .  EPA and DHA capsules were provided in a manner to reflect sporadic consumption of oily fish ( ie , 1 , 2 , or 4 times/wk ) .  EPA and DHA  were assessed at 9 time points over 12 mo in 9 sample types ( red blood cells , mononuclear cells , platelets , buccal cells , adipose tissue , plasma phosphatidylcholine , triglycerides , cholesteryl esters , and nonesterified fatty acids ) . Results : A dose response ( P < 0.05 ) was observed for EPA and DHA in all pools except for red blood cell EPA ( P = 0.057 ) . EPA and DHA measures in plasma phosphatidylcholine and platelets were best for the discrimination between different intakes ( P < 0.0001 ) . The rate of incorporation varied between sample types , with the time to maximal incorporation ranging from days ( plasma phosphatidylcholine ) to months ( mononuclear cells ) to > 12 mo ( adipose tissue ) . Conclusions : Plasma phosphatidylcholine EPA plus DHA was identified as the most suitable biomarker of acute changes in  EPA and DHA intake , and platelet and mononuclear cell EPA plus DHA were the most suitable biomarkers of habitual intake . This trial was registered at Current Controlled Trials ( www.controlled-trials.com ) as IS RCT N48398526 The authors investigated associations of serum phospholipid n-3 and n-6 polyunsaturated fatty acids ( PUFAs ) and trans-fatty acids with prostate cancer risk , and whether myeloperoxidase G-463A ( rs2333227 ) modified the associations in the Carotene and Retinol Efficacy Trial ( CARET ) ( Seattle , Washington ; Irvine , California ; New Haven , Connecticut ; San Francisco , California ; Baltimore , Maryl and ; and Portl and , Oregon , 1985 - 2003 ) . Prer and omization sera were assayed for  fatty acids  among 641 men with incident prostate cancer ( 368 nonaggressive and 273 aggressive ( stage III/IV or Gleason score ≥7 ) ) and 1,398 controls . Overall , dihomo-γ-linolenic ( quartiles 4 vs. 1 : odds ratio ( OR ) = 0.66 , 95 % confidence interval ( CI ) : 0.49 , 0.95 ; P(trend ) = 0.024 ) and docosatetraenoic ( OR = 0.69 , 95 % CI : 0.46 , 1.02 ; P(trend ) = 0.011 ) acids were inversely associated with nonaggressive and aggressive prostate cancer risks , respectively . Among men with MPO GG , the genotype upregulating oxidative stress , quartiles 4 versus 1 eicosapentaenoic plus docosahexaenoic acids were suggestively associated with an increased risk of aggressive prostate cancer ( OR = 1.66 , 95 % CI : 0.95 , 2.92 ; P(trend ) = 0.07 ) . However , the association was the inverse among men with MPO GA/AA genotypes ( P(interaction ) = 0.011 ) . Interactions were also observed for docosapentaenoic acid , total n-3 PUFAs , and arachidonic acid . MPO GA/AA vs. GG was associated with a 2-fold increase in aggressive prostate cancer risk among men with low ( quartile 1 ) n-3 PUFAs . This study adds important evidence linking oxidative stress with prostate carcinogenesis Objectives : Trends in first-time and later PSA procedure rates are ascertained using longitudinal data from a population -based cohort . These trends are compared to trends in prostate cancer incidence to determine the role of PSA in the recent decline in prostate cancer incidence . Methods : Medicare data were linked with tumor registry data from the National Cancer Institute 's Surveillance , Epidemiology , and End Results ( SE 
    Output:
    
agent
***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: Tissue levels of n-3 fatty acids reflect dietary intake , but quantitative data about rate of incorporation and levels as a function of intake are scarce . We fed 58 men 0 , 3 , 6 , or 9 g/d of fish oil for 12 months and monitored fatty acids in serum cholesteryl esters , erythrocytes , and subcutaneous fat during and after supplementation .  Eicosapentaenoic acid ( EPA ) in cholesteryl esters plateaued after 4 - 8 weeks ; the incorporation half-life was 4.8 days . Steady-state levels increased by 3.9 + /- 0.3 mass % points ( + /- SE ) for each extra gram of EPA eaten per day . Incorporation of docosahexaenoic acid ( DHA ) was erratic ; plateau values were 1.1 + /- 0.1 mass % higher for every g/d ingested . Incorporation of EPA into erythrocyte membranes showed a half-life of 28 days ; a steady state was reached after 180 days . Each g/d increased levels by 2.1 + /- 0.1 mass % . C22:5n-3 levels increased markedly . Changes in DHA were erratic and smaller . EPA levels in adipose tissue rose also ; the change after 6 months was 67 % of that after 12 months in gluteal and 75 % in abdominal fat . After 12 months each gram per day caused an 0.11 + /- 0.01 mass % rise in gluteal fat for EPA , 0.53 + /- 0.07 for C22:5n-3 , and 0.14 + /- 0.03 for DHA . Thus , different ( n-3 ) fatty acids were incorporated with different efficiencies , possibly because of interconversions or different affinities of the enzymatic pathways involved . EPA levels in cholesteryl esters reflect intake over the past week or two , erythrocytes over the past month or two , and adipose tissue over a period of years . These findings may help in assessing the intake of ( n-3 ) fatty acids in epidemiological studies BACKGROUND Fish and seafood n-3 fatty acids may prevent or delay the progression of prostate cancer , but epidemiologic studies do not uniformly support this hypothesis . OBJECTIVE We examined the relation of fish and seafood n-3 fatty acid intakes with  prostate cancer incidence and mortality . DESIGN We conducted a prospect i ve cohort study among 20,167 men participating in the Physician 's Health Study who were free of cancer in 1983 . RESULTS During 382 144 person-years of follow-up , 2161 men were diagnosed with prostate cancer and 230 died of prostate cancer . Fish intake was unrelated to prostate cancer incidence . Survival analysis among the men diagnosed with prostate cancer revealed that those consuming fish > or=5 times/wk had a 48 % lower risk of prostate cancer death than did men consuming fish less than once weekly [ relative risk ( RR ) = 0.52 ; 95 % CI : 0.30 , 0.91 ; P for trend = 0.05 ] . A similar association was found between seafood n-3 fatty acid intake and prostate cancer mortality ( RR(Q5 versus Q1 ) = 0.64 ; 95 % CI : 0.42 , 0.99 ; P for trend = 0.02 ) . These associations became stronger when the analyses were restricted to clinical ly detected cases . CONCLUSION These results suggest that fish intake is unrelated to prostate cancer incidence but may improve prostate cancer survival Systematic review s ( SRs ) are an increasingly popular evidence -based tool and are often used to answer complex research questions across many different research domains . Early SR methodology was advanced by social scientists , and the term meta- analysis was coined by a social scientist who also conducted research in psychology . SRs have recently become popular in healthcare and are likely to be beneficial in any field . The aim of this report is to highlight issues in SR conduct with a focus on the field of nutrition and to make recommendations on improving SR conduct in this area . Development of the research question is probably the most important step in conducting an SR . The 4 main components of an answerable question are 1 ) the patient , population , or problem ; 2 ) the intervention , independent variable , or exposure ; 3 ) the comparators ; and 4 ) the dependent variables or outcomes of interest . The question will be used to determine the optimal methods for conducting the SR . SRs often include study design s beyond r and omized trials and do not always include a meta- analysis of the results . Other topics explored include underst and ing and interpreting discordant review s and the importance of reporting tools [ eg , QUality Of Reporting Of Meta-analyses ( QUOROM Statement ) or CONsoli date d St and ards Of Reporting of Trials ( CONSORT Statement ) ] . Recommendations are then provided , such as developing a capacity-building program , search ing the primary literature for research gaps , and extending reporting tools such as the QUOROM Statement to the field of nutrition BACKGROUND Findings from early observational studies have suggested that the intake of dietary fat might be a contributing factor in the etiology of prostate cancer . However , the results from more recent prospect i ve studies do not support this hypothesis , and the possible association between different food sources of fat and prostate cancer risk also remains unclear . OBJECTIVE The objectives were to assess whether intakes of dietary fat , subtypes of fat , and fat from animal products were associated with prostate cancer risk . DESIGN This was a multicenter prospect i ve study of 142,520 men in the European Prospect i ve Investigation into Cancer and Nutrition ( EPIC ) . Dietary fat intake was estimated with the use of country-specific vali date d food question naires . The association between dietary fat and risk of prostate cancer was assessed by using Cox regression , stratified by recruitment center and adjusted for height , weight , smoking , education , marital status , and energy intake . RESULTS After a median follow-up time of 8.7 y , prostate cancer was diagnosed in 2727 men . There was no significant association between dietary fat ( total , saturated , monounsaturated , and polyunsaturated fat and the ratio of polyunsaturated to saturated fat ) and risk of prostate cancer . The hazard ratio for prostate cancer for the highest versus the lowest quintile of total fat intake was 0.96 ( 95 % CI : 0.84 , 1.09 ; P for trend = 0.155 ) . There were no significant associations between prostate cancer risk and fat from red meat , dairy products , and fish . CONCLUSION The results from this large multicenter study suggest that there is no association between dietary fat and prostate cancer risk BACKGROUND Laboratory studies have shown that n-3 fatty acids inhibit and n-6 fatty acids stimulate prostate tumor growth , but whether the dietary intake of these fatty acids affects prostate cancer risk in humans remains unclear . OBJECTIVE We prospect ively evaluated the association between intakes of alpha-linolenic ( ALA ; 18:3n-3 ) , eicosapentaenoic ( EPA ; 20:5n-3 ) , docosahexaenoic ( DHA ; 22:6n-3 ) , linoleic ( LA ; 18:2n-6 ) , and arachidonic ( AA ; 20:4n-6 ) acids and prostate cancer risk . DESIGN A cohort of 47 866 US men aged 40 - 75 y with no cancer history in 1986 was followed for 14 y. RESULTS During follow-up , 2965 new cases of total prostate cancer were ascertained , 448 of which were advanced prostate cancer . ALA intake was unrelated to the risk of total prostate cancer . In contrast , the multivariate relative risks ( RRs ) of advanced prostate cancer from comparisons of extreme quintiles of ALA from nonanimal sources and ALA from meat and dairy sources were 2.02 ( 95 % CI : 1.35 , 3.03 ) and 1.53 ( 0.88 , 2.66 ) , respectively .  EPA and DHA intakes were related to lower prostate cancer risk . The multivariate RRs of total and advanced prostate cancer from comparisons of extreme quintiles of the combination of EPA and DHA were 0.89 ( 0.77 , 1.04 ) and 0.74 ( 0.49 , 1.08 ) , respectively . LA and AA intakes were unrelated to the risk of prostate cancer . The multivariate RR of advanced prostate cancer from a comparison of extreme quintiles of the ratio of LA to ALA was 0.62 ( 0.45 , 0.86 ) . CONCLUSIONS Increased dietary intakes of ALA may increase the risk of advanced prostate cancer . In contrast , EPA and DHA intakes may reduce the risk of total and advanced prostate cancer Background : Estimation of the intake of oily fish at a population level is difficult . The measurement of eicosapentaenoic acid ( EPA ) and docosahexaenoic acid ( DHA ) in biological sample s may provide a useful biomarker of intake . Objective : We identified the most appropriate biomarkers for the assessment of habitual oily fish intake and changes in intake by elucidating the dose- and time-dependent response of EPA and DHA incorporation into various biological sample s that represent roles in fatty acid transport , function , and storage . Design : This was a double-blind , r and omized , controlled intervention trial in 204 men and women that lasted 12 mo .  EPA and DHA capsules were provided in a manner to reflect sporadic consumption of oily fish ( ie , 1 , 2 , or 4 times/wk ) .  EPA and DHA  were assessed at 9 time points over 12 mo in 9 sample types ( red blood cells , mononuclear cells , platelets , buccal cells , adipose tissue , plasma phosphatidylcholine , triglycerides , cholesteryl esters , and nonesterified fatty acids ) . Results : A dose response ( P < 0.05 ) was observed for EPA and DHA in all pools except for red blood cell EPA ( P = 0.057 ) . EPA and DHA measures in plasma phosphatidylcholine and platelets were best for the discrimination between different intakes ( P < 0.0001 ) . The rate of incorporation varied between sample types , with the time to maximal incorporation ranging from days ( plasma phosphatidylcholine ) to months ( mononuclear cells ) to > 12 mo ( adipose tissue ) . Conclusions : Plasma phosphatidylcholine EPA plus DHA was identified as the most suitable biomarker of acute changes in  EPA and DHA intake , and platelet and mononuclear cell EPA plus DHA were the most suitable biomarkers of habitual intake . This trial was registered at Current Controlled Trials ( www.controlled-trials.com ) as IS RCT N48398526 The authors investigated associations of serum phospholipid n-3 and n-6 polyunsaturated fatty acids ( PUFAs ) and trans-fatty acids with prostate cancer risk , and whether myeloperoxidase G-463A ( rs2333227 ) modified the associations in the Carotene and Retinol Efficacy Trial ( CARET ) ( Seattle , Washington ; Irvine , California ; New Haven , Connecticut ; San Francisco , California ; Baltimore , Maryl and ; and Portl and , Oregon , 1985 - 2003 ) . Prer and omization sera were assayed for  fatty acids  among 641 men with incident prostate cancer ( 368 nonaggressive and 273 aggressive ( stage III/IV or Gleason score ≥7 ) ) and 1,398 controls . Overall , dihomo-γ-linolenic ( quartiles 4 vs. 1 : odds ratio ( OR ) = 0.66 , 95 % confidence interval ( CI ) : 0.49 , 0.95 ; P(trend ) = 0.024 ) and docosatetraenoic ( OR = 0.69 , 95 % CI : 0.46 , 1.02 ; P(trend ) = 0.011 ) acids were inversely associated with nonaggressive and aggressive prostate cancer risks , respectively . Among men with MPO GG , the genotype upregulating oxidative stress , quartiles 4 versus 1 eicosapentaenoic plus docosahexaenoic acids were suggestively associated with an increased risk of aggressive prostate cancer ( OR = 1.66 , 95 % CI : 0.95 , 2.92 ; P(trend ) = 0.07 ) . However , the association was the inverse among men with MPO GA/AA genotypes ( P(interaction ) = 0.011 ) . Interactions were also observed for docosapentaenoic acid , total n-3 PUFAs , and arachidonic acid . MPO GA/AA vs. GG was associated with a 2-fold increase in aggressive prostate cancer risk among men with low ( quartile 1 ) n-3 PUFAs . This study adds important evidence linking oxidative stress with prostate carcinogenesis Objectives : Trends in first-time and later PSA procedure rates are ascertained using longitudinal data from a population -based cohort . These trends are compared to trends in prostate cancer incidence to determine the role of PSA in the recent decline in prostate cancer incidence . Methods : Medicare data were linked with tumor registry data from the National Cancer Institute 's Surveillance , Epidemiology , and End Results ( SE 
    Output:
    