Subclinical trauma to perineum: a possible etiology of erectile dysfunction in young men

A substantial number of young men with erectile dysfunction have neither systemic disease nor a trauma in their history. We are familiar with impotence after major trauma but it is an unanswered question whether subclinical trauma may also induce arterial degeneration with subsequent erectile dysfunction. In a period of 36 months 129 patients underwent penile arteriography. After excluding those with major surgery, trauma or psychogenic impotence 91 angiograms were reevaluated. Special attention was paid to atherosclerotic and to focal occlusive arterial disease (> 50% stenosis) in the hypogastric-cavernous branch. 12 angiograms showed normal arteries, 59 typical atherosclerotic and 20 focal occlusive arterial disease. The mean age of patients with atherosclerosis was 53 +/- 8 years versus 35 +/- 14 years of those with focal lesions (p < 0.0001). 30% with focal arterial lesions were subject to subclinical trauma. 68% with atherosclerotic disease had clinical relevant atherosclerotic risk factors. Latency between onset of erectile dysfunction and presentation at the impotence clinic was 51 months in patients with focal lesions and 39 months in those with atherosclerotic disease (nonsignificant). We conclude that subclinical trauma of the hypogatric-cavernous arteries can induce focal arterial lesions with significant impairment of perfusion. This pathology may contribute to erectile dysfunction. These patients are significantly younger and they suffer from clinically evident impotence approximately 18 years earlier than patients whose impotence is clearly of atherosclerotic origin. Focal arterial lesions due to subclinical trauma are described for the first time as an etiology of erectile dysfunction. Further studies are needed to confirm these results.     

Light-emitting porous silicon

Although porous silicon has been known for more than 35 years, only in 1990 was it recognized that porous silicon shows an increased bandgap and efficient room-temperature photoluminescence in the visible. This paper will give an overview of porous silicon research, with special emphasis on the formation mechanism of microporous silicon in terms of a depletion of holes in the porous region due to quantum confinement and the understanding of the origin of the visible luminescence. The status of research on electroluminescent and other devices based on porous silicon will be discussed, as well as results for other luminescent forms of nanocrystalline silicon.     

Gastrin and its role in the development of ulcer disease

Helicobacter pylori infected patients have increased gastrin release which shows a marked fall after cure of the infection. Recent studies indicate that inflammatory cells and cytokines play an important role in the pathogenesis of Helicobacter-associated hypergastrinemia. Views differ regarding the impact of gastrin on acid secretion. Current evidence suggests that gastrin is responsible for at least some of the increased acid secretion seen in duodenal ulcer patients.     

Microsensor-aided measurements of cellular signalling and metabolism on tumor cells. The cell monitoring system (cms(R))

Microsensors provide instruments particularly suited for the rapid, noninvasive and on-line analysis of cell and tissue cultures. The microsensor system presented in this paper is a modular arrangement of various planar and nonplanar sensor elements for the measurement of physiological parameters of cell cultures. An optic access to the cultures (e.g. for light microscopy and spectrophotometric techniques) is also provided for a parallel and comparative data acquisition. The system was originally designed for biomedical research in chemotherapy (predicative chemotherapy assays) and pharmacology but it turned out to be also an effective tool for toxicological and environmental research.