***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: Subnormal plasma zinc levels and decreased zinc concentration in hair and leucocytes as well as increased plasma ammonia and ribonuclease activity in dialyzed and nondialyzed uremic patients indicate that zinc metabolism is abnormal in uremia and is not corrected by dialysis . The effect of oral supplementation with zinc acetate  ( 12 patients ) or placebo  ( 12 patients ) on the above biochemical parameters in hemodialysis patients was determined as a part of a double-blind study . The zinc-supplemented , but not the placebo , group demonstrated significant increases in mean ( + /- SD ) , plasma zinc ( 80 + /- 9 to 110 + /- 14 , micrograms/dl ) , leucocyte zinc ( 56 + /- 13 to 1098 + /- 18 , micrograms/10(10 ) cells ) , hair zinc ( 140 + /- 12 to 190 + /- 16 micrograms/g ) , and decreases in plasma ammonia ( 76 + /- 10 to 40 + /- 6 micrograms/dl ) and plasma ribonuclease activity ( 1.49 + /- 0.08 to 0.78 + /- 0.10 , OD/min/ml ) . Abnormalities of taste and sexual function improved significantly in patients receiving zinc but not in those on placebo therapy . These improvements in biochemical as well as clinical parameters confirm and extend our earlier observations of improvement in taste and sexual function after zinc supplementation . Together , they suggest that zinc deficiency is a complicating feature of uremia and can be corrected by oral zinc supplementation Recent studies have shown that testosterone is involved in the pathogenesis of cardiovascular diseases . Moreover , in observational studies blood testosterone concentrations , result ed consistently lower , not only among men with cardiovascular disease but also in men with uremia . In order to correlate the blood level of testosterone with the degree of erectile dysfunction ( ED ) and chronic renal failure ( CRF ) ( stage I-V ) we selected a group of patients with renal failure on conservative treatment , who attended our nephrology out patients clinic . All the patients had stage II and III renal failure , respectively with a creatinine clearance between 59 - 30 and 29 - 15 ml/m ' . The sexual evaluation was done using a 15-item question naire , i.e. the International Index of Erectile Function ( IIEF ) . Mean score of patients with ED were significantly lower than mean scores for healthy controls for all 15 questions ( all p values < 0.01 ) . Preliminary results show a direct correlation between -IIEF and glomerular filtration rate ( GFR ) ( R2 0.08 ) ; an inverse correlation between testosterone and cholesterol ( R2 0.045 ) ; a higher number of diabetic patients with lower levels of testosterone , at level 3 of CRF ; low levels of testosterone for smokers especially in stage II ( GFR ) . These data confirm the direct correlation between ED and renal failure , and the role of diabetes and smoking in hypotestosteronemia , in patients with different degrees of renal insufficiency . Further prospect i ve studies are needed in order to correlate cardiovascular morbidity and mortality in patients with CRF and blood levels of testosterone The effect of zinc therapy and placebo on sexual function and endocrine status was investigated in a double-blind study of 14 male patients with chronic renal failure on regular haemodialysis .  Zinc chloride was added to the dialysate of 7 patients for 6 weeks , raising the serum zinc concentration by 17 % and placebo was added to the dialysate of the other patients . At the start of the trial 9 patients said they had decreased sexual function . Records of penile erectile activity during sleep confirmed the organic nature of the sexual dysfunction . Plasma testosterone concentrations were low or in the low normal range , basal serum luteinising-hormone levels were raised , and the early luteinising-hormone response to luteinising-hormone-releasing hormone was exaggerated , suggesting primary testicular failure . Zinc administration had no significant effect on any aspect of sexual function assessed by question naire or nocturnal penile tumescence monitoring . Plasma testosterone and basal and stimulated gonadotrophin levels were also unaltered by zinc administration BACKGROUND The aim of this study was to evaluate the safety and effectiveness of sildenafil in male peritoneal dialysis patients with erectile dysfunction . METHODS Sixteen peritoneal dialysis patients were recruited to this prospect i ve , r and omized , double-blind , placebo-controlled , crossover study of sildenafil during a period of 8 weeks . Efficacy was assessed by using the International Index of Erectile Function and a Global Assessment Question . Penile arterial supply was assessed by means of Doppler ultrasound in all patients , and adverse events were recorded . RESULTS Three patients failed to complete the study ( 1 patient received a renal transplant , 1 patient died unrelated to the study , and 1 patient withdrew for personal reasons ) . In the remainder , there was a significant improvement in erectile function with sildenafil compared with placebo ( P = 0.01 ) and the baseline assessment ( P = 0.002 ) . There were also significant improvements in intercourse satisfaction ( P = 0.002 ) and overall satisfaction ( P = 0.005 ) compared with baseline . In response to the Global Assessment Question , 75 % of patients reported improvement in erections . Only 1 adverse event was reported : a headache , which resolved after the third dose of sildenafil . CONCLUSION Sildenafil caused a significant improvement in erectile function in peritoneal dialysis patients , with a success rate at least as high as that reported in other patient groups . The drug was well tolerated , with few adverse events The aim of this study was to evaluate the efficacy and safety of oral sildenafil to treat erectile dysfunction ( ED ) in chronic renal failure in patients on hemodialysis ( HD ) . A double-blind , r and omized , placebo-controlled study of oral sildenafil ( 50 mg ) administered as required in HD patients with ED was design ed . Patients on HD for at least 6 mo and who had a stable relationship with a female sexual partner were included . Patients older than 70 yr with penile anatomic abnormalities , cirrhosis , diabetes , angina , severe anemia , and those who were on nitrate treatment or with a recent history of stroke or myocardial infa rct ion were not included . The International Index of Erectile Dysfunction ( IIEF ) was employed to evaluate ED and treatment response . Forty-one patients were evaluated ( 21 received placebo , and 20 sildenafil ) . Baseline clinical and demographic parameters were similar in both groups . Sildenafil was associated with improvement in the score of all questions and domains of the IIEF , except those related to sexual desire . Using the erectile function domain to evaluate primary efficacy , improvement was observed in 85 % of the sildenafil patients compared with 9.5 % of placebo patients . Sildenafil use result ed in normal EF scores in 35 % of sildenafil patients . Sildenafil was well tolerated . Headaches and flushing occurred in both groups . Dyspepsia was reported by two patients in the sildenafil group . In conclusion , oral sildenafil seems to be an effective and safe treatment for ED in selected patients with chronic renal failure on hemodialysis BACKGROUND Erectile dysfunction ( ED ) is prevalent in end-stage renal disease ( ESRD ) and has been associated with impaired health-related quality of life ( HRQoL ) . HRQoL , in turn , is related to morbidity and mortality in ESRD patients . Previous studies have shown improved HRQoL with ED treatment using sildenafil and vardenafil . However , no study has examined the effects of sildenafil or vardenafil on HRQoL in impotent ESRD patients . Furthermore , vardenafil has never been tested and its safety profile has not been determined in ESRD patients . The aim of this r and omized crossover study was to compare the effects of sildenafil and vardenafil on measures of HRQoL and on ED scores as well as to determine the safety profile of vardenafil in ESRD patients . METHODS In 32 haemodialysis patients with impotence , ED and HRQoL were evaluated by the International Index of Erectile Function ( IIEF-5 ) and the 36-item Short-Form Health ( SF-36 ) surveys , respectively . Patients were r and omized into sildenafil and vardenafil groups . After a 4-week treatment and 2-week washout periods , crossover was performed and an additional 4-week treatment was administered . IIEF-5 and SF-36 surveys were given before and after each treatment period . Adverse effects were evaluated by interview . Friedman tests and Bonferroni-adjusted Wilcoxon signed-rank tests were used to compare groups and for post hoc analysis , respectively . RESULTS IIEF-5 and SF-36 scores were significantly improved by both sildenafil and vardenafil compared to pretreatment values . There were no differences between sildenafil and vardenafil with respect to the studied parameters . Adverse effect profiles were also similar . No patient dropped out because of side effects . CONCLUSIONS Sildenafil and vardenafil caused similar improvements in ED and HRQoL in haemodialysis patients .  Vardenafil was well tolerated in our patient population Vardenafil , a novel selective phosphodiesterase type 5 inhibitor , was evaluated in its first large-scale at-home trial . A total of 601 men with mild to severe erectile dysfunction ( ED ) were enrolled in this multi-centre , r and omized , double-blind , placebo-controlled trial of 12 weeks of treatment with either placebo or 5 , 10 and 20 mg of vardenafil . Primary endpoints were Q3 ( vaginal penetration ) and Q4 ( maintenance of erection ) of the International Index of Erectile Function ( IIEF ) . In the intent-to-treat population ( n=580 ) , the changes from baseline for 5 , 10 and 20 mg vardenafil ( 1.2 , 1.3 and 1.5 , respectively ) were all improved ( P<0.001 ) over placebo ( 0.2 ) for Q3 and were similarly improved for Q4 ( 1.4 , 1.5 and 1.7 ) compared to placebo ( 0.5 ) ( P<0.001 ) . All vardenafil doses improved all IIEF domains compared to placebo ( P<0.001 ) . The percentage of successful intercourses was between 71 and 75 % for the three vardenafil doses . For the 20 mg dose , 80 % of the patients experienced improved erections ( GAQ ) compared to 30 % for placebo . Most frequent treatment-emergent adverse events were headache ( 7–15 % ) , flushing ( 10–11 % ) and up to 7 % for dyspepsia or rhinitis . Vardenafil treatment result ed in a high efficacy and low adverse-event profile in a population with mixed ED etiologies UNLABELLED Sildenafil citrate has shown to display beneficial cardiovascular effects , suggesting that it may have other systemic benefits involving the endothelium . There is little data regarding the long-term use of this drug and the effects of this on different organs . OBJECTIVE The primary aim of this study was to determine whether sildenafil citrate diminishes concentrations of microalbuminuria and percentage of A1c in patients with type 2 diabetes . DESIGN A double-blind , r and omized , controlled trial in 40 male patients , age 35 - 50 , with type 2 diabetes . Subjects received sildenafil citrate 50 mg daily ( n=20 ) or placebo ( n=20 ) for 30 days . Levels of hs-CRP , microalbuminuria , homocysteine , A1c and erectile function were measured at baseline and to the end of the study . RESULTS Men that received sildenafil citrate displayed a significant decrease in the microalbuminuria concentrations ( p<0.01 ) versus baseline , ( p=0.02 ) versus placebo and A1c ( p<0.01 ) versus baseline , ( p=0.01 ) versus placebo . In addition , we observed a significant increase in the total IIEF score after 30 days of treatment ( p<0.01 ) versus baseline , ( p<0.01 ) versus placebo . CONCLUSIONS The administration of 50 mg of sildenafil citrate for 30 consecutive days diminishes microalbuminuria and the percentage of A1c in patients with type 2 diabetes The aim of this study was to evaluate the effects of recombinant human erythropoietin ( Epo ) , testosterone ( T ) or a combination of them in the treatment of erectile dysfunction ( ED ) in hemodialysis patients , as well as the efficacy of sildenafil in patients unresponsive to combination treatment . A total of 23 patients with ED were divided into two groups . The international index of erectile function ( IIEF ) was used to evaluate ED and treatment response . Patients received Epo or T treatments for 12 weeks . Later on both groups received combination treatment for another 12 weeks . Although IIEF scores increased significantly in both groups after the combination treatment , the score changes were similar . After combination treatment , 16 patients still having IIEF score < 26 were given sildenafil treatment in combination with Epo while T was discontinued . Although the IIEF scores increased significantly in all patients ( 17.4 % ) , only eight of them attained an IIEF score of ≥26 . The baseline IIEF scores of the 
    Output:
    
PDE5i and zinc are promising interventions for treating  sexual dysfunction in men with CKD .
Evidence supporting their routine use in CKD patients is limited .