Dendron brushes and dendronized polymers: a theoretical outlook.

Dendron brushes are molecular structures built up of treelike macromolecules, with multiple generations of branches, grafted with a root segment to a surface (particle) or to a backbone chain (dendronized polymer) with a sufficiently high grafting density so that the dendrons interact laterally. Recent advances in the theory of dendron brushes are highlighted and complemented by insights from numerical self-consistent field modelling. Our focus is on controversial issues, which are still under debate, such as, the strain distribution in individual dendrons and the appearance of distinct populations with a different extent of stretching for dendrons in planar brushes. We anticipate that dendritic brushes (i) show a strong resistance against bending, which may manifest in a high apparent persistence length of dendronized polymers, and (ii) have an unusually large beneficial effect on the colloidal stability due to the sharp steric repulsive interaction observed when these surface layers are pushed towards the overlap.

[Validation of pre-cystectomy nomograms for the prediction of locally advanced urothelial bladder cancer in a multicentre study: are we able to adequately predict locally advanced tumour stages before surgery?]. / Validierung von Präzystektomienomogrammen zur Vorhersage lokal fortgeschrittener Harnblasenkarzinome in einer multizentrischen Studie : Können wir lokal fortgeschrittene Tumorstadien präoperativ ausreichend sicher vorhersagen?

OBJECTIVE: Pre-cystectomy nomograms with a high predictive ability for locally advanced urothelial carcinomas of the bladder would enhance individual treatment tailoring and patient counselling. To date, there are two currently not externally validated nomograms for prediction of the tumour stages pT3-4 or lymph node involvement. MATERIALS AND METHODS: Data from a German multicentre cystectomy series comprising 2,477 patients with urothelial carcinoma of the bladder were applied for the validation of two US nomograms, which were originally based on the data of 726 patients (nomogram 1: prediction of pT3-4 tumours, nomogram 2: prediction of lymph node involvement). Multivariate regression models assessed the value of clinical parameters integrated in both nomograms, i.e. age, gender, cT stage, TURB grade and associated Tis. Discriminative abilities of both nomograms were assessed by ROC analyses; calibration facilitated a comparison of the predicted probability and the actual incidence of locally advanced tumour stages. RESULTS: Of the patients, 44.5 and 25.8% demonstrated tumour stages pT3-4 and pN+, respectively. If only one case of a previously not known locally advanced carcinoma (pT3-4 and/or pN+) is considered as a staging error, the rate of understaging was 48.9% (n=1211). The predictive accuracies of the validated nomograms were 67.5 and 54.5%, respectively. The mean probabilities of pT3-4 tumours and lymph node involvement predicted by application of these nomograms were 36.7% (actual frequency 44.5%) and 20.2% (actual frequency 25.8%), respectively. Both nomograms underestimated the real incidence of locally advanced tumours. CONCLUSIONS: The present study demonstrates that prediction of locally advanced urothelial carcinomas of the bladder by both validated nomograms is not conferrable to patients of the present German cystectomy series. Hence, there is still a need for statistical models with enhanced predictive accuracy.

[A non-abscess-forming inflammation of the corpora cavernosa in a diabetic patient - case report]. / Nichtabszedierende Entzündung des Corpus cavernosum bei einem Diabetiker - Eine Fallvorstellung.

An inflammation of the corpus cavernosum is relatively rare and must be differentiated from a tumour, abscess, thrombosis or embolism of the penile vessels. Most frequently inflammation of the corpus cavernosum is caused by iatrogenic interventions, followed by general infections and acute occlusion of penile vessels. Diabetes mellitus seems to be a predisposing factor. In the case of a 51-year-old diabetic patient with painful induration of the penis, an MR imaging study was undertaken to identify an inflammation of the corpora by exclusion of abscess formation. The inflammation responded well to a two-week oral Fluorchinolon treatment. Due to its high soft-tissue contrast, multiplanar layer images and, the MR scan was performed to identify an inflammation of the corpora cavernosa and to exclude an abscess formation. We consider a therapy with oral antibiotics to be sufficient for a non-abscess-forming cavernitis.

[Abscess-forming retroperitoneal actinomycosis after urogynaecological surgery]. / Retroperitoneal abszedierende Aktinomykose nach urogynäkologischer Voroperation.

Human actinomycosis is an infrequent chronic infection caused by gram-positive anaerobic bacteria with predominantly cervicofacial and intestinal manifestation. Retroperitoneal abscess formation displays a very rare localisation and is mostly incidentally diagnosed by histological examination. We report on a 44-year-old woman with left-sided flank pain and retroperitoneal abscess formation diagnosed by CT scan. Case history revealed preceding nephroureterectomy of the left kidney due to loss of kidney function and recurrent ureteral-vaginal fistulas. After CT scan-guided puncture and negative bacterial culture, actinomycosis could only be diagnosed by histopathological examination. Subsequently, besides abscess drainage calculated antibiotic therapeutic regimen was initiated. During the follow-up of 9 months there was no local or systemic recurrence. In the present case report, aetiology, clinical symptoms as well as diagnostic and therapeutic consequences are discussed.

[Retroperitoneal bronchogenic cyst treated by laparoscopic surgery]. / Laparoskopische Entfernung einer retroperitonealen bronchogenen Zyste.

The diagnosis of primary retroperitoneal cystic tumors is very infrequent in surgical pathology. We report the case of a 51-year-old woman presenting with an incidental left-sided retroperitoneal mass (32 x 24 mm in diameter) suspected of being an adrenal tumor. Intraoperatively the tumor was identified as a cystic lesion filled with mucous secretion and laparoscopically completely resected. The diagnosis was histopathologically confirmed as a bronchogenic cyst. In this article the laparoscopic removal of such a rare benign congenital aberration resulting from an abnormal budding of the tracheobronchial tree is presented.