***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: Men with erectile dysfunction ( ED ) frequently have a disproportionate burden of comorbid vascular disorders including atherosclerotic disease . We investigated whether scheduled tadalafil is better than on-dem and ( OD ) in improving endothelium-dependent vasodilatation of cavernous arteries in men with ED and whether this effect is also exerted on markers of endothelial function . We did an open-label , r and omized , crossover study including 20 male outclinic patients aged 18 years or older ( mean age 54 years ) who had at least a 3-month history of ED of any severity or etiology .  Tadalafil ( 20 mg ) on alternate days ( ADs ) or OD was administered for 4 weeks . Primary end points were variations of basal inflow ( peak systolic velocity ( PSV ) ) and flow-mediated dilatation ( FMD ) of cavernous arteries compared with baseline at penile Duplex ultrasound . Secondary end points were variations of Q13-SIEDY scores regarding morning erections and of markers of endothelial function , that is , vascular cell adhesion molecule ( VCAM ) , intercellular cell adhesion molecule , endothelin-1 ( ET-1 ) , insulin and C-reactive protein ( CRP ) . PSVs and FMD were higher after AD treatment when compared with OD and baseline , respectively ( P=0.0001 ) , and improvements were maintained from 2 weeks after discontinuation ( P<0.005 ) . Patients receiving tadalafil  AD experienced a significant improvement of morning erections as compared to AD treatment ( P<0.0001 ) ; ET1 , VCAM and CRP showed a robust decrease after chronic vs OD regimes ( P<0.05 ) , with concomitant increase in insulin levels ( P<0.05 ) , without any variation in blood pressure and other laboratory parameters . Chronic but not OD tadalafil improves endothelial function with sustained effects from its discontinuation . Chronic treatment also produces a dramatic increase in morning erections , which determines better oxygenation to the penis , thus providing a rationale for vascular rehabilitation PURPOSE We determined the effects of intracavernosal injection ( ICI ) of recombinant basic fibroblast growth factor ( rbFGF ) on corporal tissue in hypercholesterolemic rabbits . METHODS Twenty New Zeal and White rabbits were fed a 1 % cholesterol diet for 6 weeks and were r and omly divided into four groups . Group 1 ( N = 5 ) received an ICI of phosphate buffered saline solution ( PBS ) once and again 3 weeks later . Group 2 ( N = 4 ) received an ICI of 2.5 microg rbFGF once and PBS 3 weeks later . Group 3 ( N = 6 ) received an ICI of 2.5 microg rbFGF once and again 3 weeks later . Group 4 ( N = 5 ) received an ICI of 2.5 microg rbFGF once . All animals were maintained on the  high cholesterol diet until sacrifice , 3 weeks after last injection . Strips of corporal tissue were submaximally contracted with norepinephrine , and dose-response curves were generated to evaluate endothelial-dependent ( acetylcholine , ACH ) and endothelial-independent ( sodium nitroprusside , SNP ) vasoreactivity . Protein levels of bFGF and vascular endothelial growth factor ( VEGF ) were assessed by enzyme-linked immunosorbent assay . Neuronal nitric oxide synthase ( nNOS ) protein and mRNA were detected by Western blot and semi-quantitative polymerase chain reaction , respectively . RESULTS Vasoreactivity was improved by bFGF treatment as shown by higher ED50[-log(M ) ] of ACH and SNP in Groups 2 , 3 , and 4 . The expression of bFGF protein , VEGF protein , nNOS protein , and mRNA were all increased after bFGF treatment . CONCLUSIONS ICI of bFGF improved vasoreactivity in hypercholesterolemic rabbit corporal tissue , offering a new direction to explore for the treatment of erectile dysfunction Penile NO release test ( PNORT ) has been design ed to try to evaluate clinical ly the penile endothelial function ( PEF ) . The  shear-stress flow-mediated vasodilation ( FMD )  of the cavernous arteries is evaluated in two groups of patients with neurogenic ( n=23 ) and vasculogenic ( n=23 ) erectile dysfunction ( ED ) by measuring their percent of increase after a 5 min occlusion of the flow . Both groups show an important FMD decrease ( 17.78±11.78 and 17.82±13 % ) as compared to the age-matched control group ( n=12 ) ( 65.14±30.5 % , P<0.001 ) . In the vasculogenic and control groups , mean FMD is lower in patients with one or more arterial risk factors(41 vs 67 % , P=0.025 ) , and show a positive correlation with the plasmatic levels of bioavailable testosterone ( r=0.37 , P=0.03 ) and of DHEA-S ( r=0.46 , P=0.014 ) . Patients achieving full erection at pharmacological test with visual sexual stimulation have a higher FMD ( 43.8±38 % ) than those who did not ( 18.52±14.37 % , P=0.008 ) . We confirm clinical ly that PEF is strongly impaired in organic ED linked to neurological , vascular and endocrine factors Circulating angiogenic cells ( CACs ) contribute to repair of the vessel wall and dysfunctional CACs are associated to endothelial dysfunction in men with vascular risk factors ( VRFs ) . We investigated whether inhibition of phosphodiesterase type 5 ( PDE5 ) in men with erectile dysfunction ( ED ) and VRFs is accompanied to changes of CACs and to changes of endothelial function . Thirty-six men with ED and VRFs were r and omised to 4 weeks of tadalafil ( 20mg/other day ) or placebo treatment . The number of ex vivo exp and ed functional CAC 's , identified by uptake of 1,1'-dioctadecyl-3 , 3,3 ' , 3'-tetramethylindocarbocyanine-labelled acetylated low-density lipoprotein ( DiLDL ) and concomitant Ulex europaeus agglutinin I ( UEA-1 ) binding , was determined at baseline and after treatment . The number of cells double positive for DiLDL and for UEA-1 , per high-power field fluorescence microscopy was significantly reduced in patients compared to 10 controls ( 26.88+/-6.3 and 74.41+/-17.1 , respectively ; P<0.0001 ) and was markedly increased after tadalafil treatment ( 40.69+/-13.07 versus 25.82+/-6.49 ; P<0.0001 ) . The percentage variation of CACs number and of flow-mediated dilation in the brachial artery by ultrasound after treatment was significantly associated to the presence of endothelial dysfunction at baseline . In conclusion , the increased number of functional CACs after tadalafil treatment suggests a beneficial effect of prolonged PDE5 inhibition on vascular homeostasis BACKGROUND The aim of this study was first to compare the widely used flow mediated dilation ( FMD ) method with the iontophoretically induced acetylcholine vasodilation ( IAV ) procedure . The ultimate goal was to examine the endothelial activity ( EA ) in patients with various cardiovascular risk factors compared with control subjects . PATIENTS AND METHODS In the upper extremities of 27 subjects , comparisons of EA by FMD and IAV measured with laser Doppler flux method ( LDF ) were conducted .  IAV-EA  was then measured using LDF in an additional 93 subjects with various cardiovascular ( CVD ) risk factors and /or a diagnosis of coronary heart disease ( CHD ) . RESULTS The mean age of the subjects was 56.2 years and 54 % were male . There was a robust and significant correlation between FMD vs IAV endothelial activity ( r = 0.87 , p = 0.025 ) . After adjustment for age , there were significant differences in LDF-measured , acetylcholine-induced EA by diagnosis of CHD ( p = 0.02 ) , hyperlipidemia ( p = 0.03 ) and diabetes ( p < 0.01 ) , as well as by sex ( p < 0.01 ) . The difference by hypertension status was of borderline significance ( p = 0.07 ) . LDF EA was higher in non-smokers compared to smokers but this difference was not statistically significant ( p = 0.3 ) . After adjustment for age and gender , a 10-unit increase in LDF-measured EA was associated with a 12 % lower odds for a diagnosis of CHD ( p = 0.07 ) . CONCLUSIONS Measurement of IAV-EA by LDF is a simple , noninvasive methodology which is highly correlated with post-occlusive FMD EA and is also significantly associated with a diagnosis of CHD INTRODUCTION There is considerable clinical and scientific evidence that endothelial dysfunction may be an important clinical link connecting erectile dysfunction ( ED ) with cardiovascular diseases . AIMS To modify the method of assessment of endothelial function of cavernosal arteries , to develop a new algorithm for evaluating its results , and to investigate the relationship between postocclusive changes in the diameter of brachial and cavernous arteries . METHODS The study participants were 212 patients presenting to our department complaining of ED and 40 healthy volunteers without sexual problems , which formed the control group . All patients with ED underwent complex evaluation and ultrasound assessment of postocclusive changes in the diameter of cavernosal arteries modified by us and st and ard ultrasound assessment of endothelium-dependent flow-mediated dilation of the brachial artery . MAIN OUTCOME MEASURES As the main outcome measure , the percent of increase of the cavernosal arteries diameter ( PICAD ) was recorded . RESULTS In the patients with arteriogenic ED , PICAD values were significantly less than in other groups ( P < 0.001 for pairs of comparison ) . At the same time there were no differences between the control group and groups of patients with psychogenic and organic nonarterial ED . The sensitivity and specificity of a PICAD value of 50 % in diagnosis of arteriogenic ED were 100 % and 98.2 % , respectively . In all groups and in the entire sample of patients studied we did not find a correlation between PICAD and postocclusive changes in the diameter of brachial arteries . CONCLUSION The method of ultrasound assessment of postocclusive changes in the diameter of cavernosal arteries is reliable and a highly informative tool for diagnosis of arteriogenic ED . It can not be substituted by technically simpler method of ultrasound examination of brachial arteries , while results of the latter could help to define the necessity of performing an examination of cavernous arteries INTRODUCTION Human postocclusive forearm skin reactive hyperemia is not only a potential means of identifying early signs of cardiovascular diseases , it can also be used in the assessment of local microvascular response to topically applied compounds on skin . The method is not fully characterized . In this study , we investigated the influence of occlusion time on postocclusive forearm skin reactive hyperemia using laser Doppler fluximetry ( LDF ) . METHODS Twenty healthy male volunteers were studied on three separate days ( at least 24 h apart ) via a r and omized design . Volunteers were studied in a supine position while fasted . Laser Doppler probes were placed on the volar surface of the antebrachium . In preliminary studies , 3 min of upper arm blood flow occlusion at suprasystolic pressure was found to be the upper limit of tolerability . Subsequently , volunteers were r and omized to receive 1 , 2 , or 3 min occlusion on 3 different days . Skin blood flux was measured before , during , and after occlusion using LDF . The primary outcome calculated was maximal change in skin blood flux before and after occlusion , expressed in arbitrary units ( AU ) . RESULTS Skin blood flux changes ( mean+/-S.E.M. ) after 1 , 2 , and 3 min occlusion period were 15.39+/-1.27 AU , 24.84+/-1.62 AU , and 32.14+/-1.73 AU , respectively . Using repeated- measures analysis of variance ( ANOVA ) , significant difference ( P<.05 ) in skin blood flux changes were revealed between these three occlusion duration s , where 3 min occlusion produced significantly greater in skin blood flux occlusion change compared to 1 and 2 min occlusion . DISCUSSION Three minutes of occlusion produces the greater postocclusive reactive hyperemia . It is recommended that studies using postocclusive forearm skin reactive hyperemia should occlude the forearm for at least 3 min PURPOSE We investigated changes in serum biomarkers of vascular function after short-term , continuous sildenafil dosing in men with type 2 diabetes with erectile dysfunction . MATERIAL S AND METHODS Men with erectile dysfunction associated with type 2 diabetes mellitus were r and omized to receive continuous , daily s 
    Output:
    
The established endothelial-erectile dysfunction connection was thoroughly revised , from basic mechanisms to the clinical importance of endothelial dysfunction assessment as diagnosis for generalized vascular disease .