Showing papers by "Bernhard Tribukait published in 1985"

Influence of human alpha-interferon on four human osteosarcoma xenografts in nude mice.

Abstract: Growth-inhibiting effects of human α-interferon (HulFN-α) were investigated in four human osteosarcoma xenografts in nude mice. In addition to effects on growth, the HulFN-α treatment was evaluated by histological examination and DNA flow cytometric analysis. Daily doses of 2 × 105 IU HulFN-α completely arrested the growth of two osteosarcoma xenografts and partially inhibited one, whereas 1 × 106 IU/day were necessary to arrest the growth of the fourth. Growth inhibition was reversible and tumor size independent. The histological appearance, including mitotic indices, and S-phase proportions were unchanged in three xenografts. The mechanism of the HulFN-α-induced growth inhibition of these three xenografts was therefore not considered to be a direct antiproliferative effect, but rather due to increased cell loss and/or increased cell cycle time. The modal DNA value of one xenograft was changed from aneuploid to diploid during HulFN-α treatment. Histologically, these xenografts were partly replaced by normal appearing bone and bone marrow. The S-phase proportion was also reduced in these xenografts, implying that HulFN-α can also have a direct antiproliferative effect.

Application clinique de la cytométrie de flux de I’ADN à la caractérisation des polypes colorectaux

Abstract: Nonante-huit polypes adenomateux ont ete biopsies en cours de coloscopie. Les biopsies ont ete etudiees par la methode de cytometric de flux de l’ADN. Les resultats ont ete rapportes a la taille, au type ďimplantation et a l’histopathologie des polypes. Tous les adenomes de type strictement tubulaire sont diploides. Les anomalies chromosomiales grossieres se traduisant par une distribution de l’ADN de type aneuploide, sont observees dans 31% des adenomes adenovilleux ou villeux. Elles sont presentes dans les polypes de toute taille et měme dans les cas ou une degenerescence maligne n’a pas ete suspectee par l’examen histopathologique. La cytometric de flux de l’ADN peut, pour cette raison, ětre utilisee dans le diagnostic precoce de la transformation maligne. Les resultats suggerent que meme les polypes de petite taille devraient etre systematiquement enleves par coloscopie.

DNA content and proliferation in non-Hodgkin’s lymphoma: Flow cytofluorometric DNA analysis in relation to the Kiel classification

Abstract: The Rappaport classification is widely used for diagnosis and treatment of non-Hodgkin’s lymphomas (NHL) [1–3]. However, it has become increasingly inconsistent with the rapidly changing concepts of the functional diversity of the immune system. Attempts have, therefore, been made to incorporate immunologic concepts into the morphologic classification of NHL [4, 5]. The clinical applicability of these newer classifications as well as their capacity to identify biologically distinct tumor groups is currently under study.

RNA and protein synthesis of irradiated Ehrlich ascites tumour cells. I. In vivo investigations related to the cell cycle.

Abstract: The effects of roentgen irradiation on the incorporation of 3H-uridine and 14C-leucine into RNA and protein and the RNA and protein contents of in vivo growing Ehrlich ascites tumour cells were studied. The results were related to changes in the composition of cells in cell cycle and compared with the synthesis of RNA and protein in cell material from various parts of the cell cycle obtained by means of elutriator centrifuging. The incorporation expressed by the ratio between acid insoluble/acid soluble activity was unchanged for RNA during the observation period up to 24 hours after a dose of 5.0 Gy. The ratio for protein was markedly decreased between 4 and 24 hours. This decrease was partly due to a decrease of the pool size of leucine as studied by changing the amounts of 14C leucine used. From these studies, the existence of at least two pools, an expandable and a non-expandable fixed pool can be concluded. There were no differences in the decrease of protein-synthesis between cells from the various parts of the cell cycle. The RNA and protein contents of the irradiated cells from various parts of the cell cycle corresponded to those of non-irradiated cells except for G1/early S-phase cells at 15 and 24 hours after irradiation. Possible reasons for this discrepancy are discussed.

VIe Symposium International d’Endoscopie Digestive

Abstract: A c t a Endoscopica Volume 1 5 N ~ 1 1 9 8 5 63 ENDOSCOPIC PALLIATIVE MANAGEMENT OF OESOPHAGEAL CANCER : LASER OR PROSTHESIS ? M. Buset, M. B~ive, B. Dez Marez, N. Bourgeois, C. De Boelpaepe, J. De Toeuf, M. CremerHSpital Eras.me Route de Lenr~ik 608 1070 Bruxe]]es (Belgique) In oesophageal cancer, the management if often palliative, and the endoscopic methods (prosthesis and laser photocavitation) are of great interest, because both are successfull in quick relief of dysphagia and improvement of the patient status and better tolerance to further management such 6.~ radiotherapy or chemotherapy. Patients selected have either unresectable tumors, surgical contraindications, previous radiotherap~ or surgery, metastases or tDO great local involvement. Since 1977, 130 patieDts have ~een managed by endoscopic insertion of tygon prosthesis. The successrate in dysphagia relief is 95 %. The mortaJ/ity rate is 2 %. The major complication is perforation, which occurs in 9 % of the cases. The mean survival rate is 5,8 months. On the other hand, 25 patients have been tr edted by laser photDc avitation. The successr ate is 1 O0 %, the me an survival rate 6,5 months, and only one perforation has occurred. There is no late complication. These methods can ~e compared as to their specific indications and their respective advantages. The tracheo-or bronchio-esophage al fistula is a major indication cf prosthesis. So are extrinsic structures or very long and corn plete obstructions. For prosthesis, we must mention the low cost, the very short delay for treatment completion. On the other hand, laser is bet1~r in very cervical structures, in non fully obstructive lesions. The metho d is perhaps less traumatic ( perm anent view control) with a lower perforation-rate. Some corn plic ations of prosthesis are avoided such as food im paction (shorter segment without peristalt/sm ), dislocation, pressure necrosis. There is no nee d for ge ner al anaesthesi8. Anyway, a prospective study is mandatory for better evaluation of the more specific indications and advantages of both m e tho ds. A c t a E n d o s c o p i c a V o l u m e 15 N " 1 1985 65 TRAITEMENT PALLIATIF DU CANCER DE L'OESOPHAGE PAR PROTHESES OESOPHAGIENNES A. Cusum ano, L. NorbertD, B. Martella, F. Buin, E. Ancona l&re Clinique Chirurgicale (Prof. A. Peracchia). Universit~ de Padoue, Policlinico, V. Giustiniani 2 35100 Padoue(Ita]ie) Environ 50 % des cancers de l'oesophage ne sont pas r~s6c ables en raison de leur diffusion loc ale, r~gionale ou A distance ou encore du fait de i' association de tares im portantes. Selon notre e xp@rience, i' ap plic ation d' une proth~se re pr6sente le traitement de choix du cancer oesophagien non r~s6cable. De 1967 A aoQt 1984, 633 cas de st~noses n6oplastiques primitives ou secondaires de l'oesophage ou du cardia ont 6t~ trait6es par raise en place d'une endo-proth6se oesophagienne. TABLEAU I CASUISTI QUE STENOSES OESOPHAGIENNES TRAITEES PAR PROTHESE

Cytométrie de flux du DNA sur biopsies endoscopiques dans le dépistage de la dégénérescence de la colite ulcéreuse. Etude basée sur les caractères du DNA au niveau des tumeurs gastro-intestinales

Abstract: Les caracteres du DNA cellulaire de la muqueuse de 254 patients atteints de colite ulcereuse ont ete mesures par methode de cytometrie de flux, sur biopsies prelevees en cours de coloscopie Les caracteres de DNA ont ete compares avec ceux ďadenocarcinomes du tractus gastro-intestinal Dans environ 10% des cas, un caractere DNA aneuploide a ete objective, indiquant une transformation maligne La frequence de la transformation aneuploide augmente avec la duree de la maladie A 1’oppose du caractere localise des modifications aneuploides dans les cancers colorectaux, ces memes anomalies dans la muqueuse colitique sont souvent largement disseminees Les resultats font apparaitre la possibilite de combiner coloscopie et mesures quantitatives du DNA dans la detection precoce ďune degenerescence maligne

Effects ofFoscarnet on theCellCycle

Abstract: Themechanism oftoxicity offoscarnet was studied bymonitoring itseffects on thecell cycle ofexponentially growing,semisynchronous humanembryocells inculture. Theeffects offoscarnet on thecell cycle were dependent ontheconcentration ofdrugused. At1mM,cell division was reduced by50%,whereas thecell flow was mainly reduced intheG2phaseofthecell cycle, leading toan increase intheproportion ofG2+M cells. Theminorreduction ofthymidine incorporation inSphasecells provided additional evidence that1mM foscarnet didnotspecifically inhibit DNAsynthesis. Cell division wasgreatly reduced at2.5mM foscarnet, and theG2phase was markedly affected, whereas Scell flow was less reduced. Scell flow was 10% per h and thymidine incorportation was 25%thatofcontrol cells, while a block intheG2+M phase was evident. Onthe other hand, ataconcentration of5mM foscarnet, thecell flow was greatly reduced intheGIandSphases, with less reduction ofG2cell flow andcells accumulated intheSphase. Theeffects offoscarnet on thecell cycle were more pronounced withincreasing times up to72h,whichcould notbeexplained bytheslowpenetration of foscarnet whichrequired only4to8htoachieve constant levels. At2.5and5mM foscarnet, there was the additional effect ofthecell membranes becoming more leaky as a result offoscarnet toxicity whichmight contribute tothetoxic effects ofthedrugathighconcentrations. Whenfoscarnet was removedfromthe medium, theeffects on thecell cycle wererapidly reversed, inthetimeneeded forfoscarnet todiffuse outfrom thecells, whichindicates thereversible nature ofthetoxic effects offoscarnet. Foscarnet (trisodium phosphonoformate) hasbeenshown tobeaneffective inhibitor ofthemultiplication ofseveral DNAviruses andretroviruses (see reference 8forareview). Theantiviral effect offoscarnet, apyrophosphate analog, is mediated byaninhibition ofDNA synthesis byinterference with thepyrophosphate-binding