Gastric Banding: Advantages and Complications. A 5- and 10-Year Follow-up

Background: Gastric banding is one of the simplest surgical procedures for the treatment of morbid obesity. We performed more than 150 ‘laparotomy’ (open) gastric bandings and more than 50 ‘laparoscopic’ bandings in the last 10 years. Methods: In most procedures we used non-adjustable bands, but since the beginning of 1995 we have used adjustable silicone banding. Results: The 5- and 10-year follow-up weight loss results are encouraging. The average long-term weight loss was 35.5 kg. Since 1993, we performed all the procedures laparoscopically, and the postoperative complications decreased from 18.5% in the ‘laparotomy’ group to 9.5% in the ‘laparoscopic’ group, with the majority being esophagitis and outlet area irritation. Conclusion: Gastric banding itself and especially the minimally invasive laparoscopic approach is an easy technical procedure. The long-term weight loss results and the reoperation rate are acceptable for bariatric surgery criteria.     

Concomitant blockade of P2X-receptors and ecto-nucleotidases by P2-receptor antagonists: functional consequences in rat vas deferens

In order to assess the consequences of a concomitant blockade of P2X-receptors and ecto-nucleotidases, effects of 13 P2-receptor antagonists were investigated on contractions of the rat vas deferens elicited by α,β-methylene ATP (α,β-MeATP) and ATP and on the removal of ATP from the incubation medium by vas deferens tissue. Increasing concentrations of all antagonists reduced and finally abolished contractions elicited by α,β-MeATP (3 μM), with IC₅₀-values ranging from 1.1 to 100 μM. Pyridoxalphosphate-6-azophenyl-2’,4’-disulphonate (PPADS), 6-azophenyl-4-amino-5-hydroxy-naphthalene-1,3-disulphonate (NH02), 4,4’-diisothiocyanatostilbene-2,2’-disulphonate (DIDS) and uniblue A also progressively reduced and finally abolished contractions elicited by ATP (1 mM). 8,8’-[Carbonylbis(imino-3,1-phenylenecarbonyl-imino)]-bis-(1,3,5-naphthalenetrisulphonate) (NF023), sura- min, pyridoxalphosphate-6-azophenyl-2’,5’-disulphonate (iso-PPADS), trypan blue and reactive blue 19, in contrast, caused only partial blockade, by 34–43% maximally; reactive blue 2 and reactive red 2 had no effect; and 6,6’-(1,1’-biphenyl-4,4’-diylbisazo)-bis-4-amino-5-hydroxy-naphtha-lene-1,3-disulphonate (NH01) and Evans blue even enhan- ced the response to ATP. For antagonists causing full or partial inhibition, the IC₅₀-values against ATP were close to those against α,β-MeATP. All antagonists attenuated the removal of ATP, with IC_25%-values ranging from 0.8 μM to >320 μM. The results confirm the frequent combination, in one antagonist molecule, of P2-receptor blockade and blockade of ecto-nucleotidases. This dual action underlies the effect of such compounds on contractions of the vas deferens elicited by ATP which, for certain substances (e.g., suramin, reactive blue 2), can be explained by a simple model in which the antagonist simultaneously blocks the degradation of ATP and a single contraction-mediating receptor (P2X₁). Several observations, however, do not conform with this model, and the existence of multiple contraction-mediating receptors for ATP or multiple, pharmacologically distinct ecto-nucleotidases has to be considered. Received: 23 October 1998 / Accepted: 11 January 1999     

Isolation of {gamma}-glutamyl transpeptidase positive hepatocytes during the early stages of hepatocarcinogenesis in the rat

-Glutamyl transpeptidase (GT) positive hepatocytes were isolatedfrom F344 male rats fed 2-acetylaminofluorene. The isolationprocedure is rapid and highly selective for cells exhibitingGT on their surface. Suspensions of liver cells obtained fromperfusion in situ with a collagenase solution were incubatedon Petri dishes coated with affinity purified rabbit anti-GTantibody. GT-positive cells bound to the dish within fifteenminutes and could be recovered as viable cells. Approximately15% of the GT-positive cells are isolated using this procedure.Novikoff hepatoma cells, a GT-positive cell line, were usedto define the parameters of the assay. The binding was bothtime and temperature dependent. Binding of cells to the anti-GTantibody coated dishes was 50% inhibited by 2.8 mM sodium azideand 86% inhibited by 4.6 mM.     

Influence of dietary soy isoflavones on the accessory sex organs of the Wistar rat.

We evaluated the effects of three rodent diets differing in soybean meal content on the response of the seminal vesicles, prostate and bulbocavernosus/levator ani (BC/LA) muscle to androgens and anti-androgenic compounds in the Hershberger assay. The diets tested were (1) L5, a semi-synthetic phytoestrogen-free diet, (2) DO4, 8.5% (w/w) vegetable protein and (3) DO3, 22.5% (w/w) vegetable protein. We determined the effects of dietary soy isoflavones after ten days of exposure and in animals fed L5 and DO3 diets throughout their lifetime (including the period of treatment with androgenic or anti-androgenic compounds). After ten days of exposure, we observed no effect of diet on the accessory sex organs of male Wistar rats. In contrast, diet affected the androgenic response to testosterone propionate in seminal vesicles and prostate. Seminal vesicles were the most sensitive organs. Vinclozolin caused a dose-dependent decrease in the relative weights of seminal vesicles, prostate and BC/LA regardless of diet. As vegetable proteins may contain high proportions of genistein and daidzein, two well-known oestrogenic endocrine disrupters that may alter the results of reproductive studies, we recommend the use of a standardised open-formula diet without soy isoflavones, such as L5, if the Hershberger assay is to be performed.