Toward beta-peptide tertiary structure: self-association of an amphiphilic 14-helix in aqueous solution.

A major frontier in foldamer research is creation of unnatural oligomers that adopt discrete tertiary structures; at present, only biopolymers are known to fold into such compact conformations. We report an initial step toward helix-bundle tertiary structure in the beta-peptide realm by showing that a 10-residue beta-peptide designed to adopt an amphiphilic helical conformation forms small soluble aggregates in water. Sedimentation equilibrium data indicate that the aggregated state falls in the tetramer-hexamer size range. [structure: see text]

[Intraoperative ERCP for therapy of common bile duct stones during laparoscopic cholecystectomy]. / Die intraoperative ERCP zur Behandlung der Choledocholithiasis während der laparoskopischen Cholezystektomie.

The data of 166 patients that underwent laparoscopic cholecystectomy between November 1989 and December 1997 are given. In all cases intraoperative ERC and extraction of bile duct stones within the laparoscopic surgery were performed. The results show that by intraoperative simultaneous ERC bile duct stones can be removed with a success rate of 98.8% and a mortality rate of 0%. Intraoperative ERC is a secure and economic kind of treatment, especially the patient profits from this minimal invasive procedure.

[Value of intraoperative laparoscopic cholangiography]. / Zur Wertigkeit der intraoperativen laparoskopischen Cholangiographie.

Discussion about the necessity of intraoperative cholangiography restarted when laparoscopic cholecystectomy was established. The value of cholangiography was examined in a prospectively randomized study of one hundred patients. We could show that the routinely performed intraoperative cholangiography represents a careful, secure and sensitive method for the detection of common bile duct stones. As it is not very time consuming nor linked to high costs we believe it to be unrenouncible. It allows a detailed anatomic presentation and may be combined with ERCP for definitive treatment of bile duct stones.

[Use of preventive intra-operative antibiotic administration in appendectomy. A pharmacokinetic study]. / Nutzen der intraoperativen Antibiotikaprophylaxe bei Appendektomie. Eine pharmakokinetische Studie.

Studies on Cefazedone-kinetics in serum and subcutaneous fat tissue showed an early and lasting tissue concentration high above minimal inhibitation concentrations so that intraoperative single-shot administration of antibiotics are proven to be effective. Due to these pharmacokinetic patterns the results of an earlier prospective trial is confirmed that single-shot antibiotics during surgery are useful to reduce postoperative wound sepsis rate after appendectomy.

[Proctocolectomy with direct ileoanastomosis and superimposed small intestine pouch]. / Proktocolektomie mit direkter Ileoanostomie und vorgeschalteter Dünndarmtasche.

Our experiences with 26 patients show that total proctocolectomy with direct ileoanal pouch anastomosis and without maintenance of the rectal muscle cuff proves to be an excellent method for secure and lasting treatment of UC and ACR as well as of manifest cancer. The advantage of this method is the maintenance of normal continence function at a lower operative risk and few postoperative complications. Contraindication for this operative approach is still Crohn' disease. Furthermore the indication is limited by primary dysfunction of the anal sphincter.

[Pathophysiologic role of the internal anal sphincter in chronic anal fissure]. / Zur pathophysiologischen Rolle des inneren Analsphinkters bei der chronischen Analfissur.

Internal anal sphincter manometric and myoelectrical investigations were performed under basal conditions and in response to rectal distension in 17 patients with chronic anal fissures and 15 controls. Measurement of sphincter pressures were carried out by pull-through technique, using water perfused open-tip-catheters. Electrical signals were obtained employing concentric needle electrodes inserted into the internal anal sphincter. No statistically different resting pressures were noted between patients with fissures and controls. Just so no significant difference were found in frequency and amplitude of slow potentials generated by the internal and sphincter. Neither amplitude or frequency correlate with anal sphincter pressures. In both groups, transient rectal distension produced relaxation of the internal sphincter and were associated with inhibition or irregularity of electric activity. Distribution and amplitude of internal overshoot contraction showed no difference in both groups. It can be concluded that internal sphincter spasm can not be considered as the sole cause for persistence of fissures.

[Traumatic duodenal rupture]. / Die traumatische Duodenalruptur.

Traumatic duodenal perforation has an incidence of 1%-17% (blunt injury) or 1.7%-5% (penetrating injury). Its prognosis correlates to the kind of injury, associated injuries, size of perforation and delayed diagnosis. Mortality in cases of delayed repair is 65% compared with 5% mortality in early repaired perforation. In cases of delayed diagnosis, we recommend drainage of the perforation, naso-duodenal suction tube, parenteral alimentation. 5 patients where diagnosis was delayed for 8 days or longer were treated in this way and the duodenal wound healed completely without any complications within 22-44 days.

[An elastic ileostomy sphincter using an autologous small intestine muscle flap]. / Elastischer Ileostomiesphincter durch gestielte autologe Dünndarmmuskulatur. Eine tierexperimentelle Studie.

To achieve continence in ileostomies by free transplantation of small intestinal smooth muscle according to Schmidt failed frequently because of hemorrhagic necrosis of this graft. To safeguard intact vascularisation of the transplant flapped intestinal smooth muscle was used therefore in 15 dogs with ileostomy for sphincter replacements. Contrary to free grafts, histological studies of flapped small intestinal muscle cuffs show generally undisturbed healing. Furthermore, monitoring of electrical activities corroborate the viability of the graft. In continent animals, pressure studies show the presence of a high pressure zone in the sphincter canal. The positive pressure profile was maintained and contributes to appropriate closing of the ileostomy. Despite histological, manometrical and electrical criterions of viability of the artificial sphincter, nevertheless the continence achieved by this procedure remains limited because of the restricted ability to contract the small intestinal muscle and the lacking ileal compliance.

[Therapy of intestinal bleeding by the intra-arterial injection of a synthetic vasopressin derivative]. / Therapie der intestinalen Blutung mit intraarterieller Injektion eines synthetischen Vasopressinderivates.

The synthetic drug Ornipressin was injected through a 3-French catheter introduced into the superior or inferior mesenteric artery by a coaxial method in nine patients with massive bleeding from the colon. In all patients the bleeding was stopped. In one female patient with a tumour, bleeding recurred, but was stopped by embolisation treatment. There were no complications needing treatment. As a method of treatment for bleeding from diverticula, the following procedure is recommended: an attempt should be made to stop bleeding by injecting vasopressin, or one of its derivatives and the use of a 3-French catheter by a co-axial method is advantageous. If vasopressin is contra-indicated, or is unsuccessful, catheter embolisation is recommended.

[Pseudo-obstruction of the colon]. / Die Pseudoobstruktion des Kolons.

Pseudoobstruction of the colon is characterized by clinical and radiological findings suggesting a mechanical obstruction of the large intestine without any organic cause. 11 of our patients and 344 cases reported in the literature have been reviewed. 90% of the patients have an associated major system disorder, most of them (40%) are localized in the pelvis. An imbalance in sympathetic-parasympathetic innervation as an aetiological factor is discussed. Diagnosis is generally made on the basis of the plain roentgenogram of the abdomen and a barium enema of the colon. Surgical decompression is indicated when no improvement can be achieved by conservative treatment within 72 hours. Immediate surgical intervention becomes mandatory in case of the cecal diameter being greater than 12 cm or an evident perforation. Cecostomy is of crucial benefit. Extensive necrosis requires a colonic resection.

[Pathogenesis of colon diverticular disease (author's transl)]. / Zur Pathogenese de Divertikelerkrankung des Kolons.

The longitudinal musculature of the taenia of the colon does play an important role in diverticular disease (DD), as can be found by comparing light and electron microscopic pictures of the colon from healthy persons and patients with diverticulitis and ulcerative colitis. Already in the early stages histological changes can be found, which have to be interpreted as being due to maximal contraction of the longitudinal musculature and to increased metabolism. These morphological changes are accompanied by increased electrical and mechanical activity. Disturbed function seems to be myogenic, as could be shown by studies with different drugs. These results seem to indicate that it might be preferable to incise the longitudinal musculature of the colon transversally during surgery because of diverticulosis.

[Diverticular disease; investigation on therapeutical tactics (author's transl)]. / Kolondivertikulitis. Untersuchungen zum operationstaktischen Vorgehen.

In the state of beginning complications if diverticular disease a resection of the inflammed section is indicated. This procedure prevents progression to life threatening complications. However, 5 to 30% of these patients treated in this way will have residual complaints. Our own morphological and functional in vitro investigations reveal an explanation for these findings. Furthermore, they show that the longitudinal musculature (taenias) plays a central role in the pathogenesis of the diverticular disease. The results obtained lead to the following conclusion: to make resection more complete, i.e. to prevent residual complaints and avoid relapses the longitudinal musculature should be incised transversely. Indications for taenia-myotomy are pointed out and its value is underlined by a prospective study including clinical data and functional in vivo investigations.

[On the role of myotomy in the treatment of diverticular disease (author's transl)]. / Die Myotomie im Therapiekonzept der Dickdarmdiverticulitis.

UNLABELLED: Spontaneous motor action of fresly prepared circular and longitudinal muscle strips were examined in two separated trials. Bowel musculature of diverticular patients were compared with those of normal subjects. Finally all explantations were examined histologically. RESULTS: 1. There was no difference in electrical activity and tension development regarding circular muscle strips of patients suffering from D.D. and those of normal subjects. 2. The longitudinal muscles show however significant differences in contrast to normal subjects; to sum up D.D. presents us a spastic and contracted taenia. 3. The histological investigations did not explain the different electromechanical results. There were however remarcable ribbons only in the longitudinal muscle of D.D.--known from myoma uteri. The results of the electrophysiological analysis have importance for our surgical concept in the treatment of peridiverticulitis. They justify the horizontal myotomy in the left, functionally disturbed colon descendens additional to the resection as an preventive procedure.