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: Serum and rogen levels decline with aging in normal males , such that a significant number of men over 60 yr of age will have a mean serum total testosterone ( T ) level near the low end of the normal adult range . It is not known whether lower T levels in older men have an effect on and rogen-responsive organ systems , such as muscle , bone , bone marrow , and prostate , nor are there data to evaluate the relative benefits and risks of T supplementation in older men . We assessed the physiological and biochemical effects of T therapy in 13 healthy men , 57 - 76 yr old , who had low or borderline low serum T levels ( < or = 13.9 nmol/L ) .  Intramuscular testosterone enanthate ( TE ; 100 mg weekly ) and placebo injections were given for 3 months each . Before treatment and at the end of both 3-month treatment regimens , lean body mass , body fat , biochemical parameters of bone turnover , hematological parameters , lipoprotein profiles , and prostate parameters [ such as prostate-specific antigen ( PSA ) ] were evaluated . Serum T levels rose in all subjects with TE treatment , such that the lowest level of T during a week 's period was 19.7 + /- 0.7 nmol/L ( mean + /- SE ) . After 3 months of TE treatment , lean body mass was significantly increased , and urinary hydroxyproline excretion was significantly depressed . With TE treatment , there was a significant increase in hematocrit , a decline in total cholesterol and low density lipoprotein cholesterol , and a sustained increase in serum PSA levels . Placebo treatment led to no significant changes in any of these parameters . We conclude that short term ( 3 months ) TE supplementation to healthy older men who have  serum T levels near or below the lower limit of normal for young adult men results in an increase in lean body mass and possibly a decline in bone resorption , as assessed by urinary hydroxyproline excretion , with some effect on serum lipoproteins , hematological parameters , and PSA . The sustained stimulation of PSA and the increase in hematocrit that occur with physiological TE supplementation suggest that older men should be screened carefully and followed periodically throughout T therapy Older men , particularly those with low serum testosterone ( T ) levels , might benefit from T therapy to improve bone mineral density ( BMD ) and reduce fracture risk . Concerns exist , however , about the impact of T therapy on the prostate in older men . We hypothesized that the combination of T and finasteride ( F ) , a 5 alpha-reductase inhibitor , might increase BMD in older men without adverse effects on the prostate . Seventy men aged 65 yr or older , with a serum T less than 12.1 nmol/liter on two occasions , were r and omly assigned to receive one of three regimens for 36 months : T enanthate , 200 mg i m every 2 wk with placebo pills daily ( T-only ) ; T enanthate , 200 mg every 2 wk with 5 mg F daily ( T+F ) ; or placebo injections and pills ( placebo ) . Low BMD was not an inclusion criterion . We obtained serial measurements of BMD of the lumbar spine and hip by dual x-ray absorptiometry . Prostate-specific antigen ( PSA ) and prostate size were measured at baseline and during treatment to assess the impact of therapy on the prostate . Fifty men completed the 36-month protocol . By an intent-to-treat analysis including all men for as long as they contributed data , T therapy for 36 months increased BMD in these men at the lumbar spine [ 10.2 + /- 1.4 % ( mean percentage increase from baseline + /- SEM ; T-only ) and 9.3 + /- 1.4 % ( T+F ) vs. 1.3 + /- 1.4 % for placebo ( P < 0.001 ) ] and in the hip [ 2.7 + /- 0.7 % ( T-only ) and 2.2 + /- 0.7 % ( T+F ) vs. -0.2 + /- 0.7 % for placebo , ( P < or = 0.02 ) ] . Significant increases in BMD were seen also in the intertrochanteric and trochanteric regions of the hip . After 6 months of therapy , urinary deoxypyridinoline ( a bone-resorption marker ) decreased significantly compared with baseline in both the T-only and T+F groups ( P < 0.001 ) but was not significantly reduced compared with the placebo group . Over 36 months , PSA increased significantly from baseline in the T-only group ( P < 0.001 ) . Prostate volume increased in all groups during the 36-month treatment period , but this increase was significantly less in the T+F group compared with both the T-only and placebo groups ( P = 0.02 ) . These results demonstrate that T therapy in older men with low serum T  increases vertebral and hip BMD over 36 months , both when administered alone and when combined with F. This finding suggests that dihydrotestosterone is not essential for the beneficial effects of T on BMD in men . In addition , the concomitant administration of F with T appears to attenuate the impact of T therapy on prostate size and PSA and might reduce the chance of benign prostatic hypertrophy or other prostate-related complications in older men on T therapy . These findings have important implication s for the prevention and treatment of osteoporosis in older men with low T levels BACKGROUND Despite its association with disability , death , and increased medical costs , osteoporosis in men has been relatively neglected as a subject of study . There have been no large , controlled trials of treatment in men . METHODS In a two-year double-blind trial , we studied the effect of 10 mg of alendronate or placebo , given daily , on bone mineral density in 241 men ( age , 31 to 87 years ; mean , 63 ) with osteoporosis . Approximately one third had low serum free testosterone concentrations at base line ; the rest had normal concentrations . Men with other secondary causes of osteoporosis were excluded . All the men received calcium and vitamin D supplements . The main outcome measures were the percent changes in lumbar-spine , hip , and total-body bone mineral density . RESULTS The men who received alendronate had a mean ( + /-SE ) increase in bone mineral density of 7.1+/-0.3 percent at the lumbar spine , 2.5+/-0.4 percent at the femoral neck , and 2.0+/-0.2 percent for the total body ( P<0.001 for all comparisons with base line ) . In contrast , men who received placebo had an increase in lumbar-spine bone mineral density of 1.8+/-0.5 percent ( P<0.001 for the comparison with base line ) and no significant changes in femoral-neck or total-body bone mineral density . The increase in bone mineral density in the alendronate group was greater than that in the placebo group at all measurement sites ( P<0.001 ) . The incidence of vertebral fractures was lower in the alendronate group than in the placebo group ( 0.8 percent vs. 7.1 percent , P=0.02 ) . Men in the placebo group had a 2.4-mm decrease in height , as compared with a decrease of 0.6 mm in the alendronate group ( P=0.02 ) . Alendronate was generally well tolerated . CONCLUSIONS In men with osteoporosis , alendronate significantly increases spine , hip , and total-body bone mineral density and helps prevent vertebral fractures and decreases in height BACKGROUND A large proportion of men over 65 years of age have bioavailable testosterone levels below the reference range of young adult men . The impact of this on musculoskeletal health and the potential for improvement in function in this group with testosterone supplementation require investigation . METHODS Sixty-seven men ( mean age 76 + /- 4 years , range 65 - -87 ) with bioavailable testosterone levels below 4.44 nmol/l ( lower limit for adult normal range ) were r and omized to receive transdermal testosterone  ( two 2.5-mg patches per day ) or placebo patches for 1 year . All men received 500 mg supplemental calcium and 400 IU vitamin D. Outcome measures included sex hormones ( testosterone , bioavailable testosterone , sex-hormone binding globulin [ SHBG ] , estradiol , and estrone ) , bone mineral density ( BMD ; femoral neck , Ward 's triangle , trochanter , lumbar spine , and total body ) , bone turnover markers , lower extremity muscle strength , percent body fat , lean body mass , hemoglobin , hematocrit , prostate symptoms , and prostate specific antigen ( PSA ) levels . RESULTS Twenty-three men ( 34 % ) withdrew from the study ; 44 men completed the trial . In these men , bioavailable testosterone levels increased from 3.2 + /- 1.2 nmol/l ( SD ) to 5.6 + /- 3.5 nmol/l ( p < .002 ) at 12 months in the testosterone group , whereas no change occurred in the control group . Although there was no change in estradiol levels in either group , estrone levels increased in the testosterone group ( 103 + /- 26 pmol/l to 117 + /- 33 pmol/l ; p < .017 ) . The testosterone group had a 0.3 % gain in femoral neck BMD , whereas the control group lost 1.6 % over 12 months ( p = .015 ) . No significant changes were seen in markers of bone turnover in either group . Improvements in muscle strength were seen in both groups at 12 months compared with baseline scores . Strength increased 38 % ( p = .017 ) in the testosterone group and 27 % in the control group ( p = .06 ) , with no statistical difference between the groups . In the testosterone group , body fat decreased from 26.3 + /- 5.8 % to 24.6 + /- 6.5 % ( p = .001 ) , and lean body mass increased from 56.2 + /- 5.3 kg to 57.2 + /- 5.1 kg ( p = .001 ) , whereas body mass did not change . Men receiving testosterone had an increase in PSA from 2.0 + /- 1.4 microg/l to 2.6 + /- 1.8 microg/l ( p = .04 ) , whereas men receiving placebo had an increase in PSA from 1.9 + /- 1.0 microg/l to 2.2 + /- 1.5 microg/l ( p = .09 ) . No significant differences between groups were seen in hemoglobin , hematocrit , symptoms or signs of benign prostate hyperplasia , or PSA levels . CONCLUSIONS Transdermal testosterone ( 5 mg/d ) prevented bone loss at the femoral neck , decreased body fat , and increased lean body mass in a group of healthy men over age 65 with low bioavailable testosterone levels . In addition , both testosterone and placebo groups demonstrated gains in lower extremity muscle strength , possibly due to the beneficial effects of vitamin D. Testosterone did result in a modest increase in PSA levels but result ed in no change in signs or symptoms of prostate hyperplasia Long-term glucocorticoid therapy  in men is associated with loss of bone and muscle mass as well as a decrease in serum testosterone . We tested the effect of two and rogens , testosterone and its minimally aromatizable analog n and rolone , on muscle mass ( dual x-ray absorptiometry ) , muscle strength ( knee flexion and extension by isokinetic dynamometry ) , bone mineral density ( BMD ) , and quality of life ( Qualeffo-41 question naire ) in 51 men on a mean daily prednisone dose of 12.6 + /- 2.2 mg . Men were r and omized , double blind , to testosterone ( 200 mg mixed esters ) , n and rolone decanoate ( 200 mg ) , or placebo given every fortnight by i m injection for 12 months . At 12 months , both and rogens increased muscle mass ( mean change from baseline + 3.5 % , + 5.8 % , and -0.9 % in testosterone , n and rolone , and placebo groups , respectively , P < 0.0001 ) and muscle strength ( P < 0.05 ) . Lumbar spine BMD increased significantly only in men treated with testosterone ( 4.7 + /- 1.1 % , P < 0.01 ) . There was no significant change in hip or total body BMD . Testosterone , but not n and rolone or placebo , improved overall quality of life ( P < 0.001 ) . These results suggest that and rogen therapy may have a role in ameliorating adverse effects of glucocorticoid therapy such as muscle and bone loss and aromatization is necessary for and rogen action on bone but not on muscle The pharmacokinetics , efficacy , and safety of the And roderm testosterone ( T ) transdermal system ( TTD ) and intramuscular T enanthate injections ( i.m . ) for the treatment of male hypogonadism were compared in a 24-week multicenter , r and omized , parallel-group study . Sixty-six adult hypogonadal men ( 22 - 65 years of age ) were withdrawn from prior i.m . treatment for 4 - 6 weeks and then r and omly assigned to treatment with TTD ( two 2.5-m 
    Output:
    
agent
Intramuscular testosterone moderately increased lumbar bone density in men ; the results on femoral neck bone density are inconclusive .
Without bone fracture data , the available trials offer weak and indirect inferences about the clinical efficacy of testosterone on osteoporosis prevention and treatment in men
***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: Serum and rogen levels decline with aging in normal males , such that a significant number of men over 60 yr of age will have a mean serum total testosterone ( T ) level near the low end of the normal adult range . It is not known whether lower T levels in older men have an effect on and rogen-responsive organ systems , such as muscle , bone , bone marrow , and prostate , nor are there data to evaluate the relative benefits and risks of T supplementation in older men . We assessed the physiological and biochemical effects of T therapy in 13 healthy men , 57 - 76 yr old , who had low or borderline low serum T levels ( < or = 13.9 nmol/L ) .  Intramuscular testosterone enanthate ( TE ; 100 mg weekly ) and placebo injections were given for 3 months each . Before treatment and at the end of both 3-month treatment regimens , lean body mass , body fat , biochemical parameters of bone turnover , hematological parameters , lipoprotein profiles , and prostate parameters [ such as prostate-specific antigen ( PSA ) ] were evaluated . Serum T levels rose in all subjects with TE treatment , such that the lowest level of T during a week 's period was 19.7 + /- 0.7 nmol/L ( mean + /- SE ) . After 3 months of TE treatment , lean body mass was significantly increased , and urinary hydroxyproline excretion was significantly depressed . With TE treatment , there was a significant increase in hematocrit , a decline in total cholesterol and low density lipoprotein cholesterol , and a sustained increase in serum PSA levels . Placebo treatment led to no significant changes in any of these parameters . We conclude that short term ( 3 months ) TE supplementation to healthy older men who have  serum T levels near or below the lower limit of normal for young adult men results in an increase in lean body mass and possibly a decline in bone resorption , as assessed by urinary hydroxyproline excretion , with some effect on serum lipoproteins , hematological parameters , and PSA . The sustained stimulation of PSA and the increase in hematocrit that occur with physiological TE supplementation suggest that older men should be screened carefully and followed periodically throughout T therapy Older men , particularly those with low serum testosterone ( T ) levels , might benefit from T therapy to improve bone mineral density ( BMD ) and reduce fracture risk . Concerns exist , however , about the impact of T therapy on the prostate in older men . We hypothesized that the combination of T and finasteride ( F ) , a 5 alpha-reductase inhibitor , might increase BMD in older men without adverse effects on the prostate . Seventy men aged 65 yr or older , with a serum T less than 12.1 nmol/liter on two occasions , were r and omly assigned to receive one of three regimens for 36 months : T enanthate , 200 mg i m every 2 wk with placebo pills daily ( T-only ) ; T enanthate , 200 mg every 2 wk with 5 mg F daily ( T+F ) ; or placebo injections and pills ( placebo ) . Low BMD was not an inclusion criterion . We obtained serial measurements of BMD of the lumbar spine and hip by dual x-ray absorptiometry . Prostate-specific antigen ( PSA ) and prostate size were measured at baseline and during treatment to assess the impact of therapy on the prostate . Fifty men completed the 36-month protocol . By an intent-to-treat analysis including all men for as long as they contributed data , T therapy for 36 months increased BMD in these men at the lumbar spine [ 10.2 + /- 1.4 % ( mean percentage increase from baseline + /- SEM ; T-only ) and 9.3 + /- 1.4 % ( T+F ) vs. 1.3 + /- 1.4 % for placebo ( P < 0.001 ) ] and in the hip [ 2.7 + /- 0.7 % ( T-only ) and 2.2 + /- 0.7 % ( T+F ) vs. -0.2 + /- 0.7 % for placebo , ( P < or = 0.02 ) ] . Significant increases in BMD were seen also in the intertrochanteric and trochanteric regions of the hip . After 6 months of therapy , urinary deoxypyridinoline ( a bone-resorption marker ) decreased significantly compared with baseline in both the T-only and T+F groups ( P < 0.001 ) but was not significantly reduced compared with the placebo group . Over 36 months , PSA increased significantly from baseline in the T-only group ( P < 0.001 ) . Prostate volume increased in all groups during the 36-month treatment period , but this increase was significantly less in the T+F group compared with both the T-only and placebo groups ( P = 0.02 ) . These results demonstrate that T therapy in older men with low serum T  increases vertebral and hip BMD over 36 months , both when administered alone and when combined with F. This finding suggests that dihydrotestosterone is not essential for the beneficial effects of T on BMD in men . In addition , the concomitant administration of F with T appears to attenuate the impact of T therapy on prostate size and PSA and might reduce the chance of benign prostatic hypertrophy or other prostate-related complications in older men on T therapy . These findings have important implication s for the prevention and treatment of osteoporosis in older men with low T levels BACKGROUND Despite its association with disability , death , and increased medical costs , osteoporosis in men has been relatively neglected as a subject of study . There have been no large , controlled trials of treatment in men . METHODS In a two-year double-blind trial , we studied the effect of 10 mg of alendronate or placebo , given daily , on bone mineral density in 241 men ( age , 31 to 87 years ; mean , 63 ) with osteoporosis . Approximately one third had low serum free testosterone concentrations at base line ; the rest had normal concentrations . Men with other secondary causes of osteoporosis were excluded . All the men received calcium and vitamin D supplements . The main outcome measures were the percent changes in lumbar-spine , hip , and total-body bone mineral density . RESULTS The men who received alendronate had a mean ( + /-SE ) increase in bone mineral density of 7.1+/-0.3 percent at the lumbar spine , 2.5+/-0.4 percent at the femoral neck , and 2.0+/-0.2 percent for the total body ( P<0.001 for all comparisons with base line ) . In contrast , men who received placebo had an increase in lumbar-spine bone mineral density of 1.8+/-0.5 percent ( P<0.001 for the comparison with base line ) and no significant changes in femoral-neck or total-body bone mineral density . The increase in bone mineral density in the alendronate group was greater than that in the placebo group at all measurement sites ( P<0.001 ) . The incidence of vertebral fractures was lower in the alendronate group than in the placebo group ( 0.8 percent vs. 7.1 percent , P=0.02 ) . Men in the placebo group had a 2.4-mm decrease in height , as compared with a decrease of 0.6 mm in the alendronate group ( P=0.02 ) . Alendronate was generally well tolerated . CONCLUSIONS In men with osteoporosis , alendronate significantly increases spine , hip , and total-body bone mineral density and helps prevent vertebral fractures and decreases in height BACKGROUND A large proportion of men over 65 years of age have bioavailable testosterone levels below the reference range of young adult men . The impact of this on musculoskeletal health and the potential for improvement in function in this group with testosterone supplementation require investigation . METHODS Sixty-seven men ( mean age 76 + /- 4 years , range 65 - -87 ) with bioavailable testosterone levels below 4.44 nmol/l ( lower limit for adult normal range ) were r and omized to receive transdermal testosterone  ( two 2.5-mg patches per day ) or placebo patches for 1 year . All men received 500 mg supplemental calcium and 400 IU vitamin D. Outcome measures included sex hormones ( testosterone , bioavailable testosterone , sex-hormone binding globulin [ SHBG ] , estradiol , and estrone ) , bone mineral density ( BMD ; femoral neck , Ward 's triangle , trochanter , lumbar spine , and total body ) , bone turnover markers , lower extremity muscle strength , percent body fat , lean body mass , hemoglobin , hematocrit , prostate symptoms , and prostate specific antigen ( PSA ) levels . RESULTS Twenty-three men ( 34 % ) withdrew from the study ; 44 men completed the trial . In these men , bioavailable testosterone levels increased from 3.2 + /- 1.2 nmol/l ( SD ) to 5.6 + /- 3.5 nmol/l ( p < .002 ) at 12 months in the testosterone group , whereas no change occurred in the control group . Although there was no change in estradiol levels in either group , estrone levels increased in the testosterone group ( 103 + /- 26 pmol/l to 117 + /- 33 pmol/l ; p < .017 ) . The testosterone group had a 0.3 % gain in femoral neck BMD , whereas the control group lost 1.6 % over 12 months ( p = .015 ) . No significant changes were seen in markers of bone turnover in either group . Improvements in muscle strength were seen in both groups at 12 months compared with baseline scores . Strength increased 38 % ( p = .017 ) in the testosterone group and 27 % in the control group ( p = .06 ) , with no statistical difference between the groups . In the testosterone group , body fat decreased from 26.3 + /- 5.8 % to 24.6 + /- 6.5 % ( p = .001 ) , and lean body mass increased from 56.2 + /- 5.3 kg to 57.2 + /- 5.1 kg ( p = .001 ) , whereas body mass did not change . Men receiving testosterone had an increase in PSA from 2.0 + /- 1.4 microg/l to 2.6 + /- 1.8 microg/l ( p = .04 ) , whereas men receiving placebo had an increase in PSA from 1.9 + /- 1.0 microg/l to 2.2 + /- 1.5 microg/l ( p = .09 ) . No significant differences between groups were seen in hemoglobin , hematocrit , symptoms or signs of benign prostate hyperplasia , or PSA levels . CONCLUSIONS Transdermal testosterone ( 5 mg/d ) prevented bone loss at the femoral neck , decreased body fat , and increased lean body mass in a group of healthy men over age 65 with low bioavailable testosterone levels . In addition , both testosterone and placebo groups demonstrated gains in lower extremity muscle strength , possibly due to the beneficial effects of vitamin D. Testosterone did result in a modest increase in PSA levels but result ed in no change in signs or symptoms of prostate hyperplasia Long-term glucocorticoid therapy  in men is associated with loss of bone and muscle mass as well as a decrease in serum testosterone . We tested the effect of two and rogens , testosterone and its minimally aromatizable analog n and rolone , on muscle mass ( dual x-ray absorptiometry ) , muscle strength ( knee flexion and extension by isokinetic dynamometry ) , bone mineral density ( BMD ) , and quality of life ( Qualeffo-41 question naire ) in 51 men on a mean daily prednisone dose of 12.6 + /- 2.2 mg . Men were r and omized , double blind , to testosterone ( 200 mg mixed esters ) , n and rolone decanoate ( 200 mg ) , or placebo given every fortnight by i m injection for 12 months . At 12 months , both and rogens increased muscle mass ( mean change from baseline + 3.5 % , + 5.8 % , and -0.9 % in testosterone , n and rolone , and placebo groups , respectively , P < 0.0001 ) and muscle strength ( P < 0.05 ) . Lumbar spine BMD increased significantly only in men treated with testosterone ( 4.7 + /- 1.1 % , P < 0.01 ) . There was no significant change in hip or total body BMD . Testosterone , but not n and rolone or placebo , improved overall quality of life ( P < 0.001 ) . These results suggest that and rogen therapy may have a role in ameliorating adverse effects of glucocorticoid therapy such as muscle and bone loss and aromatization is necessary for and rogen action on bone but not on muscle The pharmacokinetics , efficacy , and safety of the And roderm testosterone ( T ) transdermal system ( TTD ) and intramuscular T enanthate injections ( i.m . ) for the treatment of male hypogonadism were compared in a 24-week multicenter , r and omized , parallel-group study . Sixty-six adult hypogonadal men ( 22 - 65 years of age ) were withdrawn from prior i.m . treatment for 4 - 6 weeks and then r and omly assigned to treatment with TTD ( two 2.5-m 
    Output:
    