Long-term high-dose L-arginine supplementation in patients with vasculogenic erectile dysfunction: a multicentre, double-blind, randomized, placebo-controlled clinical trial

PURPOSE

The current randomized, double-blind, placebo-controlled clinical trial addressed the effects on penile erectile function of relatively high daily oral doses (6 g/day) of L-ARG for 3 months (N = 51) compared to placebo (N = 47), in patients with vasculogenic ED, with comparison between mild-moderate and severe vasculogenic ED.

METHODS

The outcome measures included IIEF-6 score and cavernous arteries peak systolic flow velocity (PSV) at dynamic penile duplex ultrasonography (PDU).

RESULTS

L-ARG supplementation for 3 months significantly increased IIEF-6 score in the overall cohort (p < 0.0001) and in subgroups of patients with mild-moderate (p < 0.0001) and severe (p = 0.007) vasculogenic ED; PSV was significantly increased in the overall cohort (p < 0.0001) and in patients with mild-moderate (p < 0.0001), but not severe vasculogenic ED. At study completion, 74% of patients improved ED degree category, although only 24% of patients, mainly belonging to the baseline category of mild ED, reached IIEF-6 scores compatible with absence of ED; moreover, 20% of patients, exclusively belonging to the baseline category of mild-moderate vasculogenic ED, reached PSV values compatible with absence of ED.

CONCLUSION

The results of the current study demonstrated that supplementation with relatively high doses of L-ARG as a single compound for 3 months significantly improved penile erectile function, assessed by both IIEF-6 score and PSV at dynamic PDU in patients with mild-moderate, and improved IIEF-6 score, but not PSV, in patients with severe vasculogenic ED, therefore suggesting that L-ARG might be an alternative treatment in mild-moderate vasculogenic ED patients experiencing adverse effects or with contraindications for chronic treatment with PDE5i compounds.

Quality control of ultrasound transducers: analysis of evaluation parameters and results of a survey of 116 transducers in a single hospital

PURPOSE

The aim of this study was to develop a quality control programme for ultrasound equipment and assess equipment performance at a single hospital.

MATERIALS AND METHODS

We tested 116 transducers by means of a phantom; ultrasound quality control tests were done on parameters from B-mode images, and each parameter was rated according to a three-point score as good, sufficient or poor.

RESULTS

Surface transducers showed worse performance in terms of image uniformity, with 7/55 (13%) transducers rated poor, and depth of penetration, with 24/55 (44%) transducers, rated sufficient or poor. The 3.5-MHz transducers showed worse performance in lateral resolution, with 18/48 (38%) rated poor, and particularly in focusing, with 40/48 (83%) classified as poor. In addition, the 3.5-MHz transducers proved less accurate in vertical distance accuracy than in horizontal distance, with 31/48 (64%) considered sufficient. No significant geometric distortions of masses were identified, although 4/116 (3%) transducers failed to visualise two masses.

CONCLUSIONS

The first goal of an ultrasound quality control programme is to establish specific parameters to evaluate equipment performance and, should results be below recommended action levels, implement corrective measures.

Vitamin E-coated dialyzers reduce oxidative stress related proteins and markers in hemodialysis--a molecular biological approach

BACKGROUND

Hemodialysis patients (HD) are exposed to oxidative stress which contributes to cardiovascular disease and accelerated atherosclerosis, major causes of mortality in these patients. A new dialysis membrane coated with vitamin E has been proposed against oxidative stress and atherosclerosis due to their ability to inhibit lipid peroxidation by interacting with scavengers. The mechanisms however are not completely clarified. This study evaluated, using a molecular biology approach, the effect of 6 months treatment with vitamin E-modified dialyzers, CL-E, on the gene expression of oxidative stress related proteins and markers.

PATIENTS AND METHODS

To this end, the gene expression of p22phox, a NAD(P)H oxidase subunit closely linked with the generation of superoxide anions and of Heme oxygenase-1 (HO-1), induced by and protective from oxidative stress, were evaluated by RT-PCR in mononuclear cells from 5 patients under 3 times a week chronic bicarbonate dialysis. Hydroperoxide (HPO) and total antioxidant power (AOP) plasma levels were evaluated at 3 and 6 months of treatment. HPO was also evaluated in 8 patients under CL-E treatment for 1 year and compared with 8 patients treated with cuprammonium-ryon filter (TAF).

RESULTS

p22phox mRNA decreased from 0.61 +/- 0.05 d.u. to 0.48 +/- 0.03, p < 0.01 while HO-1 increased from 0.55 +/- 0.04 d.u. to 0.62 +/- 0.03, p < 0.01. HPO decreased in CL-E treated patients: from 2.72 +/- 0.26 microM to 1.45 +/- 0.27 at 3 months (p < 0.001) to 0.87 +/- 0.11, p < 0.001 at 6 months, while AOP increased: from 752 +/- 90 mmol/L to 1057 +/- 105, p < 0.001 at 6 months. HPO was also reduced in 1 year Excebrane CL-E treated patients compared with cuprammonium treated patients: 2.25 +/- 0.3 vs. 1.42 +/- 0.11 microM, p < 0.001.

CONCLUSION

The reduced expression of oxidative stress related proteins and markers gives further support to the efficacy of the use of Vitamin E coated dialysers for the prevention or slowing progression of cardiovascular disease and atherosclerosis, major complications and causes of mortality in these patients in which oxidative stress plays a pivotal role.

[Occupational injuries with biological risk at a hospital]

A ten years retrospective study was carried out among the personnel of Padua Hospital to determine the rate of occupational exposure to blood and body fluids. 4738 injuries occurred between 1990 and 1999: 78% were percutaneous injuries 22% blood contacts. No case of operating room transmission of blood-borne infection was documented but it is clear that the risk is not zero and the number of injuries indicate the need for further training and reinforcement of universal precautions to reduce occupational exposures.