Efficacy of low-molecular-weight heparin and unfractionated heparin to prevent adhesion of human prostate and bladder carcinoma and melanoma cells to bovine endothelial monolayers. An in vitro study and review of the literature

Adherence of human prostate carcinoma (PC 3, DU 145), bladder (647 V, J 82) carcinoma and melanoma (RPMI-8252) cell lines to plastic and bovine endothelial monolayers (BEM) was tested in the presence of 0.5, 1, 5, 10, 20 IU of low-molecular-weight heparin (LMWH), unfractionated heparin (UFH) or saline as a control. Culture medium was supplemented either with 5% fetal calf serum or with human plasma. Floating tumor cells were counted after 2, 4, 24 h of culture in microtiter plates without BEM and after 1.5, 3 and 24 h of culture on BEM. Twenty IU of LMWH increased the numbers of bladder carcinoma cells adhering to BEM as did 20 IU of UFH in cultures of DU 145 prostate carcinoma and RPMI-8252 melanoma cells. LMWH obviously does not prevent human prostate and bladder carcinoma and melanoma cells from adhering to BEM more effectively than UFH. The in vivo effect of UFH and perhaps also LMWH that hinders intravenous tumor cell colonization in blood vessels obviously does not depend on the interaction with endothelial cells alone.

Colonic bacterial activity determines the symptoms in people with fructose-malabsorption

BACKGROUND/AIM

This study was performed to find a parameter to discriminate symptomatic from asymptomatic subjects with fructose-malabsorption.

PATIENTS AND METHODS

Thirty-four subjects (12 m, 22 f; average age, 28.6 years; range 16-60) were investigated after an overnight fast. After intake of 25 g fructose, H2-tests were carried out. Endexspiratory breath samples were taken before the ingestion of the tested sugar and at 30 minute intervals over a 2 hour period. Hydrogen determination was performed immediately after sampling. Results were considered pathological if there was a rise in hydrogen over 20 ppm and a twofold increase from the initial value. Aerobic and anaerobic cultures from stool bacteria were set and incubated with 0.5 g fructose.

RESULTS

Among 34 healthy controls, 13 malabsorbers (38%) were detected. Out of these malabsorbers, 6 (46%) reported gastrointestinal concomitant symptoms. Symptomatic and asymptomatic subjects with fructose-malabsorption showed a comparable increase in hydrogen levels. The disappearance rate of fructose in the stool cultures was significantly elevated in the symptomatic group compared with the asymptomatic, but only in the anaerobic culture.

CONCLUSION

This activity of colonic bacteria, significantly discriminating symptomatic subjects with fructose-malabsorption from asymptomatic, enhances the importance of fructose-malabsorption in the differential diagnosis of people with non-specific abdominal complaints. Antibiotic therapy in severe cases should be considered a therapeutical approach. Moreover these results may support the role of nutritional carbohydrates in the pathogenesis of colonic diseases.

[Hemorrhage caused by duodenal varices]

HISTORY AND CLINICAL FINDINGS

A 53-year-old man had been passing tarry stools and bright red blood per rectum for 6 days. He had a history of pyloroplasty for duodenal ulcers, alcoholic liver cirrhosis, stage B in Child's classification, a Le Veen shunt for ascites, grade I oesophageal varices and several episodes of intestinal bleeding of uncertain cause on repeated endoscopies. Haemoglobin levels was now 4.4 g/dl. Neither oesophago-gastro-duodenoscopy nor colposcopy, radiological examination of the small intestine nor scintigraphy discovered the source of bleeding. Computed tomography revealed varices in the horizontal part of the duodenum, confirmed by arteriography.

TREATMENT AND COURSE

At a second endoscopy, this time with a long scope, acute bleedings were seen in the venous convolutions and stopped with 4 ml Polidocanol. Bleeding recurred after 10 days, thought to be due to persisting portal hypertension. A transjugular intrahepatic portosystemic stent shunt (TIPSS) was inserted to lower the pressure. Colour-coded Doppler examination at the time of another bleeding 10 weeks later demonstrated occlusion of the TIPSS. It was re-opened by balloon catheter dilatation, since when there have been no further episodes of bleeding.

CONCLUSION

The implantation of a TIPSS is a new causative treatment for recurrent bleeding from ectopic varices due to portal hypertension that cannot be treated by endoscopy.

Smoking as a risk factor for duodenal ulcer relapse. RUDER Study Group

This study reports the influence of smoking on the two-year relapse rate of duodenal ulcers under treatment with ranitidine. 1899 patients with a healed duodenal ulcer received 150 mg ranitidine daily for one year, 1671 patients for two years. During this time period 23.4% of smokers relapsed compared with 26.3% of ex-smokers and 18.0% of non-smokers. The difference between smokers and ex-smokers versus non-smokers was statistically significant. There were significantly fewer relapses among smokers who stopped smoking (14.2%) compared with smokers who continued to smoke (25.2%) during maintenance treatment. These results show that continued and past smoking significantly increase the two-year relapse rate of duodenal ulcers during maintenance treatment with ranitidine.

Effect of human gastrin-17 with and without acid suppression on human esophageal motility

The putative role of gastrin for the regulation of esophageal motility is a matter of debate. Accordingly it was the aim of this study a) to examine if physiological postprandial plasma levels of human gastrin-17 (hG-17) can affect esophageal motility, especially the pressure of the lower esophageal sphincter (LESP), and b) to assess the contribution of augmented acid secretion during gastrin infusion. In a first series of experiments postprandial plasma gastrin levels were determined in 8 healthy volunteers following the ingestion of a mixed meal. Gastrin rose from a baseline of 21 +/- 2 pg/ml to 67 +/- 8 pg/ml and returned almost to basal levels within 120 minutes. In a second experimental series the effect of i.v. synthetic human gastrin-17 (hG-17) was studied in 17 volunteers. At a lower dose of 0.75 ng/kg/min hG-17 increased plasma gastrin to 62 +/- 7 pg/ml while a higher dose of 1.5 ng/kg min elicited a supraphysiological increase to 119 +/- 11 pg/ml. Infusion of hG-17 caused a significant increase of the LESP from 19.0 to 25.8 mmHg (p < 0.05, low dose) and from 18.5 mmHg to 23.3 mmHg (p < 0.05, high dose) when compared to the effect of i.v. saline. To exclude effects of augmented acid secretion during hG-17 infusion the experiments were repeated after complete blockade of acid secretion with famotidine 40 mg i.v. After famotidine pretreatment hG-17 caused a similar increase of LESP from 20.1 to 25.9 mmHg (low dose) and from 19.9 to 24.1 mmHg (high dose).(ABSTRACT TRUNCATED AT 250 WORDS)

Pantoprazole and ranitidine in the treatment of acute duodenal ulcer. A multicentre study

BACKGROUND

Pantoprazole is a new substituted benzimidazole that inhibits the parietal cell H+,K(+)-adenosine triphosphatase.

METHODS

Pantoprazole (40 mg) was compared with ranitidine (300 mg) in the treatment of acute duodenal ulcer. Two hundred and sixty-six patients with endoscopically diagnosed duodenal ulcers entered this multicentre, double-blind study. The primary efficacy variable was complete ulcer healing at 2 weeks; treatment then continued for a further 2 weeks if ulcers were unhealed.

RESULTS

After 2 weeks 112 of 164 (68%) patients in the pantoprazole group had healed ulcers, compared with 36 of 81 (44%) taking ranitidine (p < 0.001). After 4 weeks the cumulative healing rates were 96% and 85% (p < 0.01). Improvement in ulcer pain was also significantly better with pantoprazole than with ranitidine (81% versus 62% with no pain at 2 weeks, p < 0.01).

CONCLUSIONS

Pantoprazole is clinically superior to ranitidine in the treatment of acute duodenal ulcer, in terms of both healing and symptom relief.

Treatment of esophagorespiratory fistulas with silicone-coated self-expanding metal stents

Nine self-expanding silicone-coated modified Gianturco metal stents were inserted in 8 patients (mean age, 58.2 years) for palliation of malignant esophagorespiratory fistulas caused by esophageal (n = 5) or bronchial (n = 3) carcinoma. One patient with a fistula above a 12-cm-long malignant stenosis received two overlapping stents. The implantation procedure was well tolerated by all patients under intravenous sedation and analgesia. After release, the stents expanded to their full diameter, leading to complete occlusion of the fistulas and bridging of the concomitant stenoses. Two patients with lung cancer received an additional tracheobronchial stent before esophageal stent insertion. Failure to maintain complete contact between the proximal stent margin and the esophageal wall led to insufficient sealing of the fistula of 1 patient and recurrent aspiration, manifested 6 days after stent implantation (overall success, 87.5%). The other patients could swallow semi-solid food until death. Seven patients died of advanced metastatic disease after 21 to 121 days (mean, 54 days) and 1 patient of massive hemoptysis 10 days after stent placement, which could be regarded as a complication (procedure-related mortality rate, 12.5%). These preliminary results suggest that peroral insertion of the modified silicone-coated Gianturco stent is a rapid, reasonably safe, and effective procedure for palliation of malignant esophagorespiratory fistulas.

[Laser lithotripsy of refractory bile duct calculi after failure of extracorporeal shock wave treatment]

After failure of extracorporeal shockwave lithotripsy (ESWL) the benefit of further nonsurgical methods for treatment of difficult bile duct stones is undetermined. Endoscopic laserlithotripsy is a promising procedure providing target application of high energy levels.

METHOD

Twenty patients (median age: 81 [67-91] years) were referred for laserlithotripsy of 1-8 (median, 2) difficult bile duct stones after failure of 1-4 (median, 3) ESWL sessions. The median diameter of each of the largest stone was 22 (10-48) mm. The laser used was a pulsed rhodamine laser (wavelength: 594 nm) with an automatic cut-out system upon no stone contact. The laser fiber was positioned by means of ERCP under fluoroscopic control or by use of mini-cholangio-scopes. Laserlithotripsy was cholangioscopically performed via the percutaneous transhepatic route in 8 patients because of retrogradely inaccessible bile ducts (n = 5) or because further ERCP was refused (n = 3). All procedures were carried out under intravenous sedation and/or analgesia.

RESULTS

Laser lithotripsy and complete removal of fragments was achieved in 19 of the 20 patients after application of 70-25700 (median, 3310) pulses in 1.2 sessions per patient. Median duration of a single session was 70 (15-140) minutes. The procedure failed in one patient with an impacted stone at the cystic duct confluence. Cholangitis could be conservatively managed in 2 cases. No further complication was observed. The 30-day mortality rate was 0 %.

CONCLUSION

Endoscopic laserlithotripsy is an effective, a rapid and safe procedure for bile duct stones even after failure of ESWL. The results compare favorably with open surgery, particularly in view of an increased risk in a group of elderly patients.

Comparative trial of pantoprazole and ranitidine in the treatment of reflux esophagitis. Results of a German multicenter study

In 249 patients with acute symptomatic reflux esophagitis grade II and III (Savary-Miller classification), we compared the efficacy and safety of pantoprazole, a newly developed proton pump inhibitor given at a once-daily dose of 40 mg, with a standard dose of the H2 receptor antagonist ranitidine (150 mg b.i.d.) in a randomized, double-blind, multicenter study. Complete healing was achieved after 4 and 8 weeks of therapy (protocol-correct) in 69 and 82% (pantoprazole) and 57 and 67% (ranitidine), respectively (p = 0.054 at 4 weeks and p < 0.01 at 8 weeks). The predominant symptoms of gastroesophageal reflux, i.e., heartburn and acid eructation, were more effectively reduced in pantoprazole- than in ranitidine-treated patients. The frequency of adverse events was low and did not differ between the two treatment groups. We conclude that pantoprazole is superior to ranitidine in the acute treatment of reflux esophagitis.

Evaluation of submucosal upper gastrointestinal tract lesions by endoscopic ultrasound

The proper diagnosis of submucosal upper gastrointestinal tract mass lesions by endoscopy or barium study is difficult. Differentiation between submucosal tumors, vascular structures, and extrinsic organs is often impossible. We performed endoscopic ultrasound examination of 91 patients with upper gastrointestinal submucosal mass lesions. Endoscopic ultrasound was accurate in determining the site of origin in 48 of 50 cases where pathology or angiography comparison was available. Leiomyoma, lipoma, varices, and carcinoma had characteristic ultrasonographic findings. Endoscopic ultrasound is a useful procedure in the evaluation of upper gastrointestinal submucosal mass lesions.

Interstitial buffer capacity influences Na+/H+ exchange kinetics and oxyntic cell pHi in intact frog gastric mucosa

We studied the influence of interstitial buffer capacity and CO2-HCO3- on oxyntic cell intracellular pH (pHi) in intact frog gastric mucosa. Oxyntic cells in stripped gastric mucosa of Rana esculenta were loaded with the pH-sensitive dye 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein, and pHi was assessed fluorometrically. In the presence of a constant serosal and luminal pH, oxyntic cell pHi was dependent on the serosal but not the luminal concentration of cell-impermeable buffer ions such as N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES), tris(hydroxymethyl)aminomethane, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, and 3-(N-morpholino)propanesulfonic acid. The stepwise increase in oxyntic cell pHi from 6.74 +/- 0.05 with 1 mM HEPES to 7.23 +/- 0.08 was almost completely inhibited by removal of serosal Na+ and by amiloride and dimethyl amiloride, suggesting that it was largely due to Na+/H+ exchange. Increasing the serosal concentration of a CO2-HCO3- buffer from 1% CO2-4 mM HCO3- to 10% CO2-40 mM HCO3- increased oxyntic cell pHi from 7.03 +/- 0.06 to 7.39 +/- 0.07. This CO2-HCO(3-)-dependent pHi increase was also Na+ and amiloride sensitive, but high HCO3- concentrations increased pHi even in the absence of Na+, K+, or Cl-, and in the presence of omeprazole, bafilomycin A1, or acetazolamide. We suggest that in intact frog gastric mucosa, cellular proton extrusion acidifies the interstitial pH immediately adjacent to the basolateral membrane of the oxyntic cells in the absence of a high interstitial buffer capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of endogenous opioids on vagally induced release of gastrin, somatostatin and bombesin-like immunoreactivity from the perfused rat stomach

The aim of the present study was to evaluate the effect of the opiate receptor antagonist naloxone on vagally stimulated secretion of bombesin-like immunoreactivity (BLI), somatostatin and gastrin from the isolated rat stomach, which was perfused via the celiac artery with Krebs-Ringer buffer. Vagal stimulation was performed for 10 min with 1 ms, 10 V and 2, 5, 10 or 20 Hz, respectively. In control experiments BLI release increased significantly above basal secretion during a stimulation frequency of 10 Hz (1367 +/- 357 pg/10 min; P < 0.001) and 20 Hz (996 +/- 202 pg/10 min; P < 0.01), but not at 2 and 5 Hz. In comparison to the controls naloxone (10(-6) M) significantly increased BLI secretion at 5 Hz by 573 +/- 150 pg/10 min (P < 0.05), but attenuated the BLI response to higher stimulation frequencies of 10 and 20 Hz to 284 +/- 143 pg/10 min (P < 0.001) and 490 +/- 114 pg/10 min (P < 0.01), respectively. At 2 Hz naloxone had no effect on BLI release. As shown previously the cholinergic blocker atropine (10(-7) M) induced a significant BLI release during vagal stimulation at 2 Hz (680 +/- 233 pg/10 min; P < 0.01) and 5 Hz (935 +/- 324 pg/10 min; P < 0.05), but was without effect at 10 and 20 Hz compared to the controls. The effects of the combination of naloxone and atropine were similar to naloxone and atropine alone. Naloxone had no effect on vagal or GRP-induced regulation of gastrin and somatostatin release.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pyrimethamine-sulfadiazine resistant cerebral toxoplasmosis in AIDS]

A 48-year-old man with known HIV infection for 4 years was admitted with a 2-week history of increasing brachio-facial paraesthesiae of the left side of the body and pains in the head and neck. Physical examination also showed discrete slowing of mental activity and oral candidiasis. Toxoplasmosis serology showed a low titre with a borderline IgM titre. Cranial computer tomography showed two confluent contrast medium concentrating foci in the region of the head of the caudate nucleus and the right internal capsule. Because toxoplasmosis encephalitis was suspected, treatment was started with sulfadiazine (1 g four times daily), pyrimethamine (25 mg four times daily), folic acid (15 mg daily) and dexamethasone (8 mg three times daily). After 19 days of treatment there was no clinical improvement, and a check CT scan showed worsening with increased oedema of the cerebellar medulla, compression of the lateral ventricles and a mid-line shift of 5 mm. Since the Sabin-Feldman test titre had increased, and there was no evidence to suggest a lymphoma or a viral or fungal infection, toxoplasmosis resistant to standard therapy was postulated, and treatment was started with clindamycin (600 mg three times daily) and pyrimethamine (25 mg four times daily). The clinical features subsided within 4 days. A further check CT scan 14 days later showed almost complete resolution.

Cholestasis induced hyperthyroidism after liver transplantation

We report the case of a 68-year-old woman who underwent liver transplantation because of hepatitis-C-induced cirrhosis. She developed iodine-reduced hyperthyroidism postoperatively in temporal relation with cholestatic jaundice. Hepatic biopsies revealed moderate intrahepatic cholestasis and mild lobular inflammatory infiltration with some eosinophils. No histological evidence of acute graft rejection or reactivated hepatitis was found. Treatment with methimazole markedly reduced the serum parameters of cholestasis which, after subtotal thyroidectomy, returned to normal. Liver function recovered, as confirmed by repeated aminopyrine breath tests.

[MALT lymphoma, stomach carcinoma--role of Helicobacter pylori. Are chances for prevention on the horizon?]

The pathogenesis of gastric carcinoma developing after infection with Helicobacter pylori now seems to be clear. The release of urease, alcohol dehydrogenase, enzymes and cytotoxin on the one hand, and chemotactic factors, PAF and heat-shock proteins on the other trigger chronic inflammation and epithelial metaplasia and dysplasia in the stomach. Under the influence of additional carcinogens, the epithelial changes progress to severe dysplasia and finally carcinoma. As a result of chronic inflammation, MALT lymphomas can also be induced. These can be made to regress by eradicating Hp. The possibility of being able to prevent up to 80% of the carcinomas of the stomach by eradicating Hp holds out good prospects, over the long-term, for the prevention of these tumors. Accurate identification of the patient groups carrying a high risk is now necessary.

Different regulation by pHi and osmolarity of the rabbit ileum brush-border and parietal cell basolateral anion exchanger

1. The purpose of this study was to look for evidence of a pH-sensitive modifier site on the parietal cell basolateral anion exchanger, determine the pH range in which allosteric regulation takes place, investigate the effect of the osmolarity on internal pH (pHi) dependence and compare it with that of the ileum brush-border anion exchanger. 2. When the pHi in parietal cell basolateral membrane (BLM) vesicles was increased, the rate of Cl(-)-gradient-driven 36Cl- uptake increased from 6.03 +/- 2.24 to 38.09 +/- 3.33 nmol (mg protein)-1 with the steep increase in anion exchange rates occurring within a narrow pH range between pHi 7.0 and 7.5. This was due to allosteric activation by internal OH- and not due to a change in driving force, since the driving force for maximal exchange rates was provided by the outwardly directed Cl- gradient. 3. The pHi dependency curve of parietal cell BLM anion exchange rates was shifted to the left by 0.25 pH units by increasing the osmolarity of the intra- and extravesicular solutions from 300 to 380 mosmol l-1. Thus cell shrinking may activate the parietal cell anion exchanger without a change in pHi and without phosphorylation of the anion exchanger protein. 4. In ileum brush-border membranes, the pHi-dependent increase in the rate of Cl(-)-gradient-driven 36Cl- uptake was more gradual and the half-maximal anion exchange rate was attained at lower pHi (pH 6.5). Increasing the osmolarity from 300 to 500 mosmol l-1 had no effect on pH dependence. 5. We conclude that the parietal cell basolateral and ileum brush-border anion exchangers possess an internal modifier site for allosteric activation by OH-, but the pH range in which allosteric regulation occurs differs between the two exchangers, as does the effect of an increase in osmolarity. Since current evidence suggests that both the parietal cell basolateral and the ileum brush-border anion exchanger are encoded by the AE2 gene, the differences in pHi dependence between the two may be due to alternative splicing, post-transcriptional modification, or the different membrane environment. 6. The pHi range for allosteric activation found in this study would suggest that for both the ileum and the parietal cell anion exchanger, but especially for the latter, a potentiating effect of the allosteric activation and the HCO3- availability occurs within the physiological pHi range and can cause dramatic increases in maximal anion exchange rates with increasing pHi.