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Imprint cytology specimens of metastases of intestinal carcinoids obtained by percutaneous biopsy were analysed cytofluorometrically with regard to nuclear DNA records. All untreated tumors (nine cases) exhibited diploid DNA values with a relatively low proliferative activity (less than 2% nuclei in S-phase region). The mean number of tetraploid cells was 5%. Cytofluorometry also was performed on five tumor metastases treated with the cytotoxin streptozotocin and 5-fluorouracil. After treatment, an increase in the number of tetraploid cells (mean value, 30%) was noted, indicating that the cytotoxin treatment (possibly streptozotocin) on the tumor cells in vivo blocked progression from G2 to M phase. The current cytofluorometric analyses show that diploid nuclear DNA records and a low proliferative activity is a characteristic of malignant carcinoid tumors of the intestine. Due to regular DNA histograms in the carcinoid tumors, it is suggested that reliable studies are permitted of the effect of cytotoxins on the different phases of the cell cycle in vivo.

A method for clinical studies of ground reaction forces during gait is presented. A walkway consisting of two force measuring platforms, each five meter long, allows the recording from several consecutive steps from both feet. Signals from photocells and goniometers have been added and a microcomputer system for on line recording and processing have been developed. The accuracy of the system is tested.

Ten patients with malignant endocrine pancreatic tumors were treated with SMS 201-995 at doses of 50 micrograms twice daily, administered subcutaneously. Four out of 10 patients (40%)-1 patient with the Zollinger-Ellison syndrome and 3 of 6 with the watery diarrhea syndrome--responded objectively with more than 50% reduction of peptide levels, with a median duration of 15.5 months. All four patients improved symptomatically, with decreasing dyspeptic symptoms and decreasing diarrhoea. Three additional patients had a clear relief of symptoms without an effect on tumor-secreted peptides. The disease progressed in three patients during treatment. No reduction of tumor mass was seen in any of the patients. The main side effect noted was a slight but maintained increase in fasting blood glucose in four patients. In conclusion, SMS 201-995 had a beneficial effect in more than half of the patients and seems to be a valuable adjunct to other causal therapy in this patient category, especially in acute situations and weak patients because of its very few side effects.

By using only reverse-phase h.p.l.c., three fragments of prosomatostatin were isolated from an extract of a human pancreatic neuroendocrine tumour that produced somatostatin, vasoactive intestinal polypeptide and gastrin-releasing peptide. The amino acid composition of the peptides indicated that they represented prosomatostatin-(1-63)-peptide, prosomatostain-(65-76)-peptide and prosomatostatin-(79-92)-peptide (somatostatin-14). The identity of prosomatostatin-(1-63)-peptide was confirmed by characterization of the products of digestion with Armillaria mellea (honey fungus) proteinase. Partial micro-sequencing of prosomatostatin-(1-63)-peptide showed that the Gly24-Ala25 bond of preprosomatostatin was the site of cleavage of the signal peptide. Thus human prosomatostatin is a protein of 92 amino acid residues that is proteolytically cleaved in a pancreatic tumour at the site of a dibasic-residue (arginine-lysine) processing site and at a single-monobasic-residue (arginine) processing site.