J. Lawrence Werther

Experimental models for gastric leiomyosarcoma. The effects of N-methyl-N'-nitro-N-nitrosoguanidine in combination with stress, aspirin, or sodium taurocholate.

A series of experiments was devised to determine possible modifying effects of stress, aspirin, and sodium taurocholate on the activity of N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG) in the Buffalo rat stomach. MNNG is a well known, direct‐reacting carcinogen, and has been a reliable agent for the experimental production of gastric adenocarcinoma. The authors were able to produce adenocarcinomas in rats, but found a great number of gastric leiomyosarcomas. These occurred only in the groups given MNNG in combination with stress, aspirin, or sodium taurocholate, and did not occur in experimental groups given either MNNG, stress, aspirin, or sodium taurocholate alone, and did not occur in the control group. Cancer 53:1088‐1092, 1984.

Amyloidosis in regional enteritis: A report of five cases

Abstract 1.1. Amyloidosis was found at autopsy in five of seventeen patients who died as a result of regional enteritis or its complications. 2.2. In two of the cases presented, death was due to renal failure resulting from renal amyloidosis; in one other, renal and adrenal amyloidosis were significant factors in the fatal outcome. 3.3. The occurrence of amyloidosis could not be related to the duration or extent of the enteritis, or to the presence of gross suppuration or the formation of fistulas. 4.4. It is suggested that clinical evidence of amyloidosis appearing in the course of regional enteritis constitutes an indication for resection of the diseased bowel.

Mucosal Blood Flow in Canine Antral and Fundic Pouches

Aminopyrine clearance was used to compare mucosal blood flow in the resting and stimulated fundus and antrum. The intraluminal instillation of 0.16 n HCl provided a p H gradient allowing aminopyrine to move into the lumen. Resting mucosal perfusion was 0.64 ± E 0.23 (sd) ml per min per g of mucosa for the fundus and 0.34 ± E 0.10 ml per min per g of wet mucosa for the antrum. Extrapolated mucosal blood flow of the resting fundus by plotting aminopyrine clearance against acid output during secretory stimulation correlated well with mucosal blood flow during acid instillations. Graded doses of histamine by intravenous infusion stimulated mucosal blood flow in the fundus parallel to acid secretion; a maximal dose (2 μg of base per kg per min) increased mucosal perfusion of the fundus 4-fold and doubled antral mucosal perfusion. Isoproterenol (1 μg per kg per min intravenously) increased mucosal blood flow to the resting fundus by 100% and to the antrum by 110%. Vasopressin (4 mU per kg per min intravenously) decreased resting fundic mucosal blood flow by 75% and antral blood flow by 80%. The present study lends further support to the validity of aminopyrine clearance as a measure of mucosal blood flow. It is further shown that: (1) aminopyrine clearance in the fundus and antrum is not dependent on the secretion of hydrogen ions and can be measured by using exogenous acid; (2) no redistribution of mucosal blood flow from antrum to corpus occurs with histamine stimulation; (3) primary alterations in mucosal blood flow can be induced in both pouches by vasoactive drugs without affecting acid secretion.

Seroprevalence of Helicobacter pylori infection in patients with lymphoma.

To determine the Helicobacter pylori (HP) seroprevalence in patients with non-Hodgkins lymphoma (NHL) and other hematological conditions. Sera were collected from 444 patients with NHL, Hodgkins disease (HD), lymphoproliferative disorders (LPD), myeloproliferative disorders (MPD), and other hematological conditions. HP seropositivity was determined by ELISA and the results were compared among diagnostic groups HP seropositivity was observed in 168/444 (38%) of the total population. Higher seropositivity rates were associated with increasing age (p=0.001), and country of birth outside the USA and Canada (p=0.0001). Among the diagnostic groups, patients with NHL demonstrated the highest frequency (43%) and those with HD, the lowest frequency (20%; p=.026) of HP seropositivity. The differences among diagnostic groups remained statistically significant after controlling for country of birth (p< 0.05), but not after controlling for patient age at diagnosis. The HP seroprevalence of GI NHL was 55% compared to 40% for non-GI NHL (p=NS). The highest rate of HP seropositivity (67%) occurred in gastric MALT lymphoma patients, although this did not reach statistical significance compared to the non MALT group (50%) due to small sample size. In conclusion, the rate of HP seropositivity in patients with MALT lymphoma in the USA appears to be lower than in Europe. Helicobacter pylori does not appear to be an important factor in other types of NHL of the GI tract or elsewhere. Studies of HP prevalence should be controlled for country of birth as well as for age.

Gastric cation secretion in a patient with complete esophageal obstruction and permanent gastrotomy

Summary and conclusions1. Variation in the electrolytes of the gastric secretion, in response to several different stimuli, were determined in a patient with complete esophageal stenosis and a permanent gastric fistula, and are generally in agreement with those previously reported from this laboratory under a variety of conditions.2. The rise in [K] following histamine stimulation previously observed in patients with unoperated stomachs was not the result of salivary contamination.3. The rise in [K] in response to vagomimeric stimulation with Mecholyl is much smaller than that observed with histamine.4. There is a definite increase in K output with all stimuli; this is most marked after histamine.5. The Na output declines after histamine, but it increases after sham feeding and Mecholyl stimulation.

Hydrogen permeability of canine gastric antral and fundic mucosa following exposure to pancreatic juice

Abstract The effects of pancreatic juice were evaluated on ionic movement across fundic and antral mucosa. Solutions of 0.16 N HCl were instilled into vagally denervated fundic asd antral pouches. Pancreatic juice applied topically to gastric mucosa had no effect on the antrum and only a brief significant effect on the fundus. Loss of H + was mildly increased and this was rapidly reversible. If reflux of duodenal contents is important in the etiology of gastric ulcers, it is concluded that impairment of the mucosal barrier is the result of bile reflux rather than that of pancreatic juice.