Pathophysiological levels of soluble P-selectin mediate adhesion of leukocytes to the endothelium through Mac-1 activation

Plasma soluble P-selectin (sP-selectin) levels are increased in pathologies associated with atherosclerosis, including peripheral arterial occlusive disease (PAOD). However, the role of sP-selectin in regulating leukocyte-endothelial adhesion is unclear. The aim of this study was to assess the ability of exogenous and endogenous sP-selectin to induce leukocyte responses that promote their adhesion to various forms of endothelium. In flow chamber assays, sP-selectin dose-dependently increased neutrophil adhesion to resting human iliac artery endothelial cells. Similarly, sP-selectin induced neutrophil adhesion to the endothelial surface of murine aortae and human radial venous segments in ex vivo flow chamber experiments. Using intravital microscopy to examine postcapillary venules in the mouse cremaster muscle, in vivo administration of sP-selectin was also found to significantly increase leukocyte rolling and adhesion in unstimulated postcapillary venules. Using a Mac-1-specific antibody and P-selectin knockout mouse, it was demonstrated that this finding was dependent on a contribution of Mac-1 to leukocyte rolling and endothelial P-selectin expression. This was confirmed in an ex vivo perfusion model using viable mouse aorta and human radial vessels. In contrast, with tumor necrosis factor-alpha-activated endothelial cells and intact endothelium, where neutrophil adhesion was already elevated, sP-selectin failed to further increase adhesion. Plasma samples from PAOD patients containing pathologically elevated concentrations of sP-selectin also increased neutrophil adhesion to the endothelium in a sP-selectin-dependent manner, as demonstrated by immunodepletion of sP-selectin. These studies demonstrate that raised plasma sP-selectin may influence the early progression of vascular disease by promoting leukocyte adhesion to the endothelium in PAOD, through Mac-1-mediated rolling and dependent on endothelial P-selectin expression.     

The use of the vacuum-assisted closure in microsurgical reconstruction revisited: application in the reconstruction of the posttraumatic lower extremity

Introduction of vacuum-assisted closure (VAC) system into clinical practice has revolutionized wound care. Despite its multiple advantages, however, the VAC is only rarely used in the setting of microsurgical reconstruction. Concerns have been the inability to clinically monitor the flap as well the possibility of flap compression by the device. The authors put their postoperative treatment concept of applying the VAC to free flaps to the test by reviewing their experience with this concept in patients undergoing microsurgical reconstruction of posttraumatic lower-extremity soft tissue defects. Twenty-six patients (22 male, 4 female) were included in this study. Use of the implantable Doppler probe allowed for postoperative flap monitoring. Two flap failures were observed, both in patients with peripheral vascular disease. In conclusion, using the VAC device in the setting of microsurgical reconstruction is safe and allows for increased patient comfort.     

Einzelbasenpaarpolymorphismen und erektile Dysfunktion

The risk for erectile dysfunction is closely linked to cardiovascular morbidities such as coronary heart disease, arterial hypertension, hypercholesterolemia, and diabetes. Molecular analysis revealed an association between the genotypes in single base polymorphisms and the risk for these cardiovascular morbidities. In this review the current knowledge of association studies of single nucleotide polymorphisms and erectile dysfunction and the response to the PDE-5 inhibitor sildenafil is described.     

Schwerwiegende kindliche Anomalien des Harntrakts

As urinary tract obstruction in children may impair renal function, the early detection and evaluation of the degree of obstruction using adequate diagnostic tools is necessary for the choice of the optimal therapeutic procedure. This study describes diagnostic and therapeutic standards in relation to the quality of management of pediatric hydronephrosis in Germany in the first 6 months of the year 2000. In our study 407 of 711 (57.2%) children with a hydronephrotic condition were detected by routine ultrasound. This, and the fact that 25% of the patients, who were prenatally detected, had a diagnosis of vesicoureteral reflux, underlines the importance of this routine procedure. Our study illustrates the panel of diagnostic and therapeutic procedures used in the management of pediatric hydronephrosis in Germany.     

Energy metabolism and histomorphological findings in replanted rat hind limbs using various conservation methods

Using various storage and conservation methods, we examined amputated and subsequently replanted limbs for their ischaemia tolerance level by investigating the changes in the adenylphosphocreatine system and glycolysis cycle. After replantation, amputated limbs that had been stored at room temperature (21.0 ± 1.5°C) for 2 hours were examined 14 days after operation. The adenosine triphosphate level of the skeletal muscle was reduced to 51% and the creatine phosphate to 77% of that of the control group. The glycogen was 13% of the normal value. The biochemical findings correlate with the histomorphological findings. After 2 hours ischaemia, the cross striations of the skeletal muscle and nuclear staining remained intact. There is a breakdown of the biochemical systems after 4 hours of ischaemia. They are no longer intact and the ischaemic limb does not recover. Histologically, muscle necrosis can be observed.