Biomedical subjects

H P Wünsch

Publications and source records attributed to H P Wünsch.

4 recordsLinked to original sources

PubMed1991

DNA aneuploidy and proliferation in spontaneous human and dimethylhydrazine-induced murine colorectal carcinogenesis.

DNA aneuploidy and proliferative abnormalities were studied by flow cytometry in 169 colorectal specimens from 162 patients. Of 37 adenomas, three showed aneuploidy and another seventeen revealed a "near diploid" DNA pattern. The rate of aneuploid and "near diploid" DNA changes in 92 carcinomas was 53.3% and 23.9%, respectively. No correlation was seen between the ploidy distribution and the stage or histologic grade of the carcinomas. The S-phase fractions of both adenomas and carcinomas significantly increased from the diploid (8.1 +/- 0.8% and 7.8 +/- 0.9% respectively; mean +/- SEM) to the "near diploid" (14.9 +/- 1.2% and 12.6 +/- 1.5%) and aneuploid (20.4 +/- 1.3% and 11.4 +/- 1.6%) lesions. To better understand neoplastic progression at very early stages, flow cytometry was also performed on 195 colonic specimens of 44 rats treated by weekly subcutaneous injections of 21 mg/kg Dimethylhydrazine. There was a single "near diploid" carcinoma in this group, and all other induced neoplasms (39 carcinomas and 27 adenomas) revealed a diploid DNA pattern. The S-phase fractions were as follows: controls (38 untreated animals) 8.6 +/- 0.1%, normal mucosa (of Dimethylhydrazine exposed rats) 10.1 +/- 0.25% (p less than 0.0001), adenomas 13.9 +/- 0.6% (p less than 0.01), and carcinomas 14.7 +/- 0.6% (p less than 0.01). These findings support the conclusion that genomic alterations and proliferative abnormalities may already be present in premalignant human colonic lesions. However, despite strong morphological similarities, major biological differences exist between the Dimethylhydrazine-induced murine intestinal carcinogenesis and spontaneously occurring human colorectal neoplasms.

Adolescent↗

PubMed1988

[Experimental comparison of Maxon and chromic catgut in suturing of the urinary bladder].

The new monofile absorbable suture material Maxon was compared with Chromic catgut in bladder suturing in rabbits. Comparisons were made after 1, 2, 4, 8 and 12 weeks. The rate of stone formation was mainly determined by the suture technique used and not so much by the suture material. This was demonstrated by the low number of stones formed after using extramucosal suturing technique. Once a suture, be it Maxon or Chromic catgut, comes in contact with urine, concrements may form and the new monofile properties of Maxon do not offer any advantages here. On the other hand, Maxon does not enhance stone formation either. E. coli or Proteus infections did not influence formation of stones. The histological examinations showed Maxon to cause fewer inflammatory reactions. Sutures with Chromic catgut caused inflammation of the bladder wall, subsiding after 4 weeks. An existing urinary infection did not appear to influence the inflammatory process. Maxon offers an advantage over Chromic catgut in extramucosal sutures causing fewer inflammatory reactions.

Animals↗

PubMed1983

Can a substitute for the bladder sphincter be attained by free transplants derived from vesical muscle tissue?

Smooth muscle transplants of the intestinal tract have been tested experimentally as a substitute for the bladder sphincter. An attempt was made to apply the proposed technique to the vesical muscle tissue and to achieve a sphincter replacement with freely transplanted autologous bladder tissue. An internal urethrotomy was performed several times in female sheep until a complete urinary incontinence resulted. For the bladder sphincter substitute a strip of vesical tissue was dissected from the anterior wall and following pre-stretching it was sewed circumferentially around the urethra in order to constrict it. The urethral pressure was registered during the operation before and after application of the sphincter 'graft'. For temporary urinary discharge a suprapubic catheter was inserted. The sheep were examined clinically and urodynamically for up to 3 months. Complete urinary continence was not obtained in any of the cases. The urodynamic examination showed a nearly complete loss of the urethral pressure which had been obtained by the operation. The histological studies showed progressing fibrosis of the desired continence zone. By way of freely transplanted autologous vesical muscle a sphincter substitute could not be achieved.

Animals↗

PubMedDate not supplied

[Scanning electron microscopy and elementary analytic studies of osteosarcoma].

By scanning electron microscopical (SEM) screening analyses of 14 osteosarcomas characteristic three-dimensional structures of tumor osteoid could be demonstrated. These osteoid formations are highly characteristic for osteosarcoma; we did not find them at any other bone tumor or tumor like lesion until now. With these results a better understanding of characteristic growth patterns of bone tumors could be achieved by SEM. No specific results could be found by elementar analysis, x-ray microanalysis, x-ray fluorescence and x-ray diffractometer techniques. The significance of single interesting values has to be evaluated in the future.

Bone Neoplasms↗