[Operative therapy for stress urinary incontinence in men--from sling to artificial sphincter]

Radical prostatectomy is the most common cause of male urinary incontinence. Up to 90% of the patients are incontinent in the early postoperative phase. This rate reduces to 3-23% approximately 12 months after prostatectomy. Male slings and the ProACT™-Ballon system are preferred minimal invasive therapeutic options for mild to moderate incontinence. Mid-term continence rates of 50-80% can be achieved with bone anchored and adjustable slings or the adjustable ProACT™-Ballon system. The results after radiation therapy are significantly poorer. Randomised controlled trials with longer follow-ups are necessary in order to evaluate the effectiveness of these options for continence therapy. Considering the high continence rates of 73-92% in long-term follow-ups, the artificial urinary sphincter (AUS) still remains the gold standard in the therapy for incontinence in men with normal dexterity and mental status. In cases where continence cannot be achieved by implantation of an AUS, a urinary diversion can be taken into consideration.

Molecular mechanism of selectivity among G protein-coupled receptor kinase 2 inhibitors

G protein-coupled receptors (GPCRs) are key regulators of cell physiology and control processes ranging from glucose homeostasis to contractility of the heart. A major mechanism for the desensitization of activated GPCRs is their phosphorylation by GPCR kinases (GRKs). Overexpression of GRK2 is strongly linked to heart failure, and GRK2 has long been considered a pharmaceutical target for the treatment of cardiovascular disease. Several lead compounds developed by Takeda Pharmaceuticals show high selectivity for GRK2 and therapeutic potential for the treatment of heart failure. To understand how these drugs achieve their selectivity, we determined crystal structures of the bovine GRK2-Gβγ complex in the presence of two of these inhibitors. Comparison with the apoGRK2-Gβγ structure demonstrates that the compounds bind in the kinase active site in a manner similar to that of the AGC kinase inhibitor balanol. Both balanol and the Takeda compounds induce a slight closure of the kinase domain, the degree of which correlates with the potencies of the inhibitors. Based on our crystal structures and homology modeling, we identified five amino acids surrounding the inhibitor binding site that we hypothesized could contribute to inhibitor selectivity. However, our results indicate that these residues are not major determinants of selectivity among GRK subfamilies. Rather, selectivity is achieved by the stabilization of a unique inactive conformation of the GRK2 kinase domain.

[Urology needs health services research: the case of small renal tumours]

The central tasks of health services research include the description and analysis of health care under everyday conditions as well as the development and evaluation of new concepts. As a first step, the reality of the health services' situation should be assessed using representative data. For that, registries, claims data of health insurance funds or observational studies are suitable. To investigate specific patterns or decisions, qualitative methods are of importance. To evaluate the effectiveness of health care concepts or structures, pragmatic randomized, controlled trials are considered to provide the best evidence. In this paper we discuss these questions on the basis of treatment for patients with small renal masses. Although recent guidelines recommend nephron-sparing surgery instead of radical nephrectomy for these patients, international studies suggest that there is a significant underuse of nephron-sparing procedures. However, national data describing the situation in Germany are necessary to analyse reasons and to develop new concepts which subsequently have to be tested in randomized trials. Therefore, the aim of health services research is to create a scientific basis for continuous improvements in health care. Urology needs health services research and we should find ways to overcome barriers to improve quality of care.

Changes in popliteal vein diameter and flow velocity with knee flexion and hyperextension

Objective

To compare popliteal vein (PV) diameter and peak flow velocity generated by a calf compressor, when the knee is either flexed or hyperextended.

Method

Subjects lay supine on a couch with a calf compressor on each leg. Peak flow velocities in the PV were measured by duplex ultrasound during activation of the compressor, when the knee was either flexed or hyperextended. Hyperextension of the knee is seen when the heel is elevated to prevent heel pressure ulcers.

Results

The results were analysed using the Wilcoxon signed rank test. This showed a significant increase in peak flow measurements related to narrowing of the PV when the knee was hyperextended.

Conclusion

There is a functional narrowing of the PV during hyperextension of the knee. We developed a model, which postulates an increase in the risk of deep vein thrombosis in patients whose knee is hyperextended. Based on this model, we suggest that the knee should be flexed slightly when patients are supine and anaesthetized.

Analyses of loss-of-coolant accidents involving release of insulation material under consideration of the measures taken for PWR from expert's point of view

The incident, which happened in the Swedish nuclear power plant Barsebäck 2 on 28th of July, 1992 brought about a re-evaluation of the design requirements for the control of loss-of-coolant accidents (LOCA) involving the release of insulation material that were valid in Germany up to that time. The current paper provides an overview on the aspects that need to be taken into consideration for analyses as well as a description of the important boundary conditions. In giving details of the analyses, the actual state is also described. It is also illustrated that sufficient examinations and tests have been performed for the German PWR plants and corresponding measures have been taken providing a sufficient basis for a final positive evaluation of the issue “LOCA involving release of insulation material”.

[Anterior cruciate ligament reconstruction using quadriceps tendon autograft and press-fit fixation]

BACKGROUND

Reconstruction of the anterior cruciate ligament (ACL) is a widely used procedure, but up to now no results have been published on an implant-free technique using a quadriceps tendon autograft and press-fit fixation.

METHODS

A total of 112 patients with primary rupture of the anterior cruciate ligament were included in a prospective case control study and 106 patients could be evaluated postoperatively after a mean of 12.4 months (range 12-14 months).

RESULTS

The patients showed good to excellent results according to the Lysholm score in 81% and the International Knee Documentation Committee (IKDC) score in 86% of cases. Furthermore the anterior-posterior translation was less than 3 mm in 83% of the patients by testing with the KT-1000 arthrometer. Neither tunnel widening nor an increase of radiological joint degeneration was recorded by radiological examination.

CONCLUSION

Reconstruction of the ACL with an autologous quadriceps tendon and an implant-free technique yielded good results compared to established operative methods in the short-term and should be consistently followed-up for long-term confirmation.

Polymorphism 1558 C > T in the aromatase gene (CYP19A1) in low-grade endometrial stromal sarcoma

Low-grade endometrial stromal sacomas (ESS) are estrogen-sensitive tumors. Polymorphic variation in the CYP19 gene can affect estrogen synthesis by increasing aromatase activity resulting in elevated levels of estrone and estradiol. We examined the polymorphism 1558 C > T in he aromatase gene (CYP19A1) in a series of 20 low-grade endometrial stromal sarcomas. Archival formalinfixed and paraffin-embedded material was analyzed with a fast real-time PCR system. The homozygous C/T- and the homozygous mutant T/T-genotypes were detected in 10/20 (50%) and 7/20 (35%) samples, respectively. Polymorphism 1558 C > T in the aromatase gene may represent a high-risk allele with increased local estrogen levels.

Pathophysiology of the vascular wall and its relevance for cerebrovascular disorders in aged rodents

Chronic hypertension and cerebral amyloid angiopathy (CAA) are the main pathologies which can induce the rupture of cerebral vessels and intracerebral hemorrhages, as a result of degenerative changes in the vascular wall. A lot of progress has been made in this direction since the successful creation of the first mouse model for the study of Alzheimer's disease (AD), as the spectrum of AD pathology includes a plethora of changes found in pure cerebrovascular diseases. We describe here some of these mouse models having important vascular changes that parallel human AD pathology, and more importantly, we show how these models have helped us understand more about the mechanisms that lead to CAA formation. An important cellular event associated with reduced structural and functional recovery after stroke in aged animals is the early formation of a scar in the infarcted region that impairs subsequent neural recovery and repair. We review recent evidence showing that the rapid formation of the glial scar following stroke in aged rats is associated with premature cellular proliferation that originates primarily from the walls of capillaries in the corpus callosum adjacent to the infarcted region. After stroke several vascular mechanisms are turned-on immediately to protect the brain from further damage and help subsequent neuroregeneration and functional recovery. Although does occur after stroke, vasculogenesis is overshadowed in its protective/restorative role by the angiogenesis and arteriogenesis. Understanding the basic mechanisms underlying functional recovery after cerebral stroke in aging subjects is likely to yield new insights into the treatment of brain injury in the clinic.

Investigation of IGF2/ApaI and H19/RsaI polymorphisms in patients with cutaneous melanoma

OBJECTIVE

The etiology of cutaneous melanoma is complex, involving both heterogeneous genetic and environmental components. The aim of our study was to verify if single polymorphic sites within IGF2 and H19 genes and their consequent haplotypes influence risk and/or prognosis of familial melanoma.

DESIGN

Twenty one patients with clinical criteria of hereditary melanoma (early onset, presence of multiple primary melanoma, and/or one or more affected first- or second-degree relatives) and previously screened for CDKN2A mutations were genotyped by IGF2/ApaI and H19/RsaI PCR-RFLPs. Data were compared between patients and a control group (100 healthy young individuals) using Chi-square and Fisher's exact tests. We also investigated if these polymorphic sites could be microRNAs potential targets, using RegRNA software.

RESULTS

Although the IGF2 and H19 genotypes/haplotypes were not significantly associated with melanoma, two of the most severe cases (very early onset or multiple melanomas) showed to be heterozygous for both genes. We found an overlap between IGF2/ApaI and miR-615-5p, and between H19/RsaI and miR-574-3p.

CONCLUSIONS

Some studies have shown H19, and IGF2 genes (or related genes or protein, for example, IGF2R and IMP-3) differential expression in melanoma. However, no study has attempted to examine markers across this cluster in relation to melanoma until now. Since the base change may impair the pairing of microRNA and its binding site, our results suggest a new window for future studies of IGF2 and H19 genetic variability and posttranscriptional regulation. Due to the importance and based on the present results, we suggest that the genotype/haplotype analysis of IGF2 and H19 polymorphisms should be better investigated in large populations with cutaneous melanoma, attempting to tie the association with progression of the disease.

[Tumours of the Kidney: CT vs. MRI. Nearly equal alternatives with minor differences]

Because of progress in imaging, the incidence of renal tumours, especially small lesions, has been rising over the last years. Therefore, imaging must be done to decide how to proceed further. But which is the most effective modality: computed tomography (CT) or magnetic resonance imaging (MRI)? From the technical point of view, the two alternatives appear to be nearly equal. Multidetector CT remains the reference standard for staging and lesion characterisation, whereas MRI is the method of choice for determining caval extension of a tumour thrombus and infiltration of the renal vein. If an accurate diagnosis cannot be specified, the remaining modality should be used complementarily.

[Conservative management of postoperative urinary incontinence in men]

Urinary incontinence in men most commonly occurs after radical prostatectomy. Of these patients, 3-23% remain incontinent a year after prostatectomy. Data on conservative therapy for postoperative incontinence is contradictory. Nonetheless, conservative treatment strategies must generally be attempted before any operative technique. Early pelvic floor muscle training with or without biofeedback therapy and duloxetine seem to have a positive effect on continence. Further randomised controlled studies are necessary to accurately assess other conservative therapeutic options such as extracorporeal magnetic innervation and electrical stimulation therapy.

Structure of human G protein-coupled receptor kinase 2 in complex with the kinase inhibitor balanol

G protein-coupled receptor kinase 2 (GRK2) is a pharmaceutical target for the treatment of cardiovascular diseases such as congestive heart failure, myocardial infarction, and hypertension. To better understand how nanomolar inhibition and selectivity for GRK2 might be achieved, we have determined crystal structures of human GRK2 in complex with Gbetagamma in the presence and absence of the AGC kinase inhibitor balanol. The selectivity of balanol among human GRKs is assessed.