PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “GASTRIC MUCOSA”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Cell kinetics of human gastric mucosa and gastric cancer in organ culture.

The cell kinetics of human gastric epithelium in organ culture have been measured using flash labelling with tritiated thymidine and the metaphase arrest technique to estimate cell birth rates. Normal gastric antral and body mucosa have been compared with mucosa showing gastritis and gastric carcinoma. Labelling indices with tritiated thymidine in normal gastric mucosa declined over a 48-h period suggesting that essential growth factors were lacking. Labelling indices and cell birth rates were higher in gastritis than in normal mucosa and highest in gastric carcinoma. Labelling indices were higher in intestinal-type gastric carcinoma than diffuse carcinoma. In metaphase arrest experiments carcinomas showed on average an eightfold increase in resistance to the metaphase-arresting properties of vincristine when compared with normal mucosa. The validity of using the metaphase arrest technique to measure cell birth rate in gastric cancers in view of this vincristine resistance is discussed.

Cell Cycle↗

Immunohistochemical localization of CD44 variants 5 and 6 in human gastric mucosa and gastric cancer.

The aim of this study was to compare the distribution of CD44 variants 5 and 6 in normal mucosa and gastric cancer and to determine their relationship with histoclinical Parameters of the disease. Experimental material included 112 paraffin blocks of various human gastric carcinomas. Both variants of CD44 were detected immunohistochemically with primary antibodies deriving from Bender Med. Systems. In normal gastric mucosa positive reactions with both antibodies were observed in surface epithelium, parietal cells, myocytes and vascular endothelia. They were also found in intestinal enterocytes, esophageal epithelium and myoepithelial. Additional reactivity with antibodies against variant 6 was observed in Paneth cells. In gastric cancer, variants 5 and 6 were demonstrated in 91% and 64% of cases respectively, without significant correlation with the tumor type. The occurrence of variant 6 correlated positively with tumor size (p = 0.081) and negatively with histological grading (p = 0.093). The relationship with metastases was insignificant.

Carrier Proteins↗

H+ production by isolated cells from human gastric mucosa.

Gastric mucosal cells were isolated from human mucosa obtained at surgery. H+ production was indirectly estimated by 14C aminopyrine (AP) uptake. The maximal response to histamine occurred after 30 min of incubation whereas intrinsic factor (IF) secretion was maximal after only 7.5 to 15 min. According to the concentration response curve 10(-4) mol/1 histamine proved to be the most effective concentration, the response to which was completely inhibited by ranitidine. Carbachol, dibutyryl cAMP and IMX also enhanced AP uptake, IMX being even more powerful than histamine. Carbachol and IMX failed to potentiate the response to histamine. Parietal cell fractions enriched by a Percoll density gradient revealed a pronounced background stimulation so that additional stimulation by test agents was less effective than in non-fractionized cells.

Adult↗

[Comparison of the histopathological findings among the biopsies of non-cancerous gastric mucosa of patients with gastric cancer and the biopsies of gastric mucosa of dyspeptic patients without gastric cancer].

Gastric biopsies of the non neoplastic area of 46 patients with gastric cancer and 59 gastric biopsies of dyspeptic patients without gastric cancer were reviewed by one pathologist, without knowing from which group they were coming, to determine the histopathologic findings. The results of both groups were compared. Intestinal metaplasia was found to be significantly higher in gastric cancer patients than in patients without neoplasia (54,3 and 25,4% respectively) (p=0,001). Also in patients with cancer and intestinal metaplasia, this was of the complete type in about 80% of the cases. A number of items were assessed using logistic regression, we found that the presence of complete metaplasia, gastric atrophy and hypertrophy of the mucinogenous vacuole correlates with the presence of gastric cancer (p=0,0159 0,0080 y 0,0280 respectively). H.pylori presence was similar in both groups. The study was done between November 1997 and November 1998 at the Cayetano Heredia National Hospital and the National Institute of Neoplastic Diseases.

Aged↗

Involvement of ornithine decarboxylase and polyamines in epidermal growth factor-induced recovery of gastric mucosa from gastric lesions provoked by stress.

Polyamines such as spermine or putrescine, resulting from increased activity of ornithine decarboxylase (ODC), are known for gastroprotective and mucosal growth promoting effects but little information is available about their role in the acceleration of the healing of stress-induced gastric lesions by epidermal growth factor (EGF). In this study, rats with intact or suppressed ODC activity by alpha-difluoromethylornithine (DFMO, 400 mg/kg i.p.) were subjected to 3.5 h of water immersion and restraint stress (WRS) without or with intragastric (i.g.) administration of spermine and putrescine or with subcutaneous (s.c.) injection of EGF. At 0, 2, 6, 12 and 24 h after stress, rats were killed and the number of gastric lesions was counted, gastric blood flow (GBF) was recorded by the H2-gas clearance technique, the gene expression of ODC mRNA using reverse-transcriptase polymerase chain reaction (RT-PCR) and the ODC activity in this mucosa were determined in oxyntic mucosa. Stress produced gastric lesions combined with decreased GBF (by approximately 43%), but at 2, 6, 12 and 24 h after stress, these lesions and the fall in GBF were gradually attenuated. Healing of stress lesions was accompanied by strong stimulation of ODC mRNA expression and by an immediate increase in enzyme activity, with a peak occurring about 6 h after stress. Pretreatment with DFMO or salivectomy (which resulted in a marked fall in luminal EGF levels and mucosal DNA synthesis) delayed significantly the healing of stress lesions. EGF or spermine significantly accelerated the ulcer healing and raised the GBF. Suppression of endogenous generation of prostaglandins (PGs) with indomethacin (5 mg/kg i.p.) almost completely reversed the EGF- and spermine-induced acceleration of the healing of stress lesions and the accompanying rise in GBF. DFMO significantly reduced the enhancement in healing and the rise in the GBF induced by EGF, but failed to influence those induced by exogenous spermine. The acceleration of the healing induced by spermine or EGF and accompanying hyperemia were not affected by salivectomy. We conclude that (1) upregulation of the ODC transcript, increased ODC activity and polyamines play an important role in mucosal recovery from stress lesions due to acceleration of mucosal repair and an increase in gastric microcirculation, (2) increased ODC activity and resulting excessive polyamine release appear to act as primary mediators of EGF-induced acceleration of healing of stress lesions and (3) endogenous PGs cooperate with EGF and polyamines in mucosal repair from stress ulcerations.

Animals↗

[Effect of diacarb on the carbonic anhydrase activity in the blood and gastric mucosa and pepsinogen concentration in the gastric mucosa of the rat].

It was established that the activity of blood and gastric mucosa carboanhydrase increased after the introduction of food irritant (milk) into the stomach, as well as after the subcutaneous injection of histamine. This was accompanied by the increase of pepsinogen content in the gastric mucosa. When introduced into the stomach before the food irritant or histamine, acetazolamide inhibited blood and gastric mucosa carboanhydrase and reduced the content of pepsinogen in the gastric mucosa. Oral administration of acetazolamide for 5 days resulted in a more remarkable inhibition of blood and gastric mucosa carboanhydrase and in a drastically reduced content of pepsinogen in the gastric mucosa. The rate of pepsinogen biosynthesis by the gastric mucosa seems to depend on the activity of carboanhydrase in blood and in the gastric mucosa.

Acetazolamide↗

Difference in chromatin sensitivity to heparin of chronic atrophic gastritis, of carcinoma-free and carcinoma-bearing stomach in comparison with normal gastric mucosa and gastric carcinoma as revealed by flow cytometry.

DNA distribution patterns from gastric mucosal cells corresponding to four groups defined by histological examination were measured by flow cytometry before and after treatment with heparin, a polyanion. Group I comprised normal gastric mucosal cells; group II, chronic atrophic gastric mucosal cells originating from a carcinoma free stomach; group III, chronic atrophic gastric mucosal cells originating from a carcinoma bearing stomach; and group IV, malignant gastric mucosal cells. The heparin concentrations used were 1.25, 1.5, and 5 U/ml cell suspension. Heparin caused increases in fluorescence intensity and in coefficients of variation, which are interpreted as a reflection of alterations in chromatin structure. For the four groups investigated, the heparin-initiated changes were dependent, in varying degree, on concentration and time. Group I showed a much more extensive sensitivity to heparin than group IV. Group II and III reacted similarly to group I or group IV, depending on the source, i.e., either a carcinoma-free stomach or a carcinoma-bearing stomach. Further extension of this method might yield information concerning the real premalignant potential of a specific case of chronic atrophic gastritis.

Chromatin↗

Enhanced expression of manganese superoxide dismutase mRNA and increased TNFalpha mRNA expression by gastric mucosa in gastric cancer.

Manganese superoxide dismutase (Mn-SOD), a mitochondrial enzyme, is a cytokine-regulated acute-phase protein that protects cells from free radicals. The current investigations examined the in vivo regulation of the expression of Mn-SOD mRNA and tumor necrosis factor alpha (TNFalpha) mRNA in gastric carcinoma tissue. The expression of these transcripts in breast carcinoma tissue also was examined because breast cancer is a much more TNF-sensitive tumor than gastric cancer. TNFalpha mRNA was markedly increased in gastric carcinoma tissue (p < 0.005). There were significantly higher levels of Mn-SOD mRNA in gastric carcinoma tissue than in noncancerous tissue (p < 0.0001). The level of Mn-SOD mRNA in gastric carcinoma tissue was higher than that in breast carcinoma tissue (p < 0.005). Up-regulation of Mn-SOD mRNA in gastric carcinoma tissue most likely serves as a protective mechanism against superoxide radicals and TNF cytotoxicity.

Adult↗

Reduced amoxicillin uptake into human gastric mucosa when gastric juice pH is high.

Amoxicillin when administered with gastric acid suppressors has been shown to be effective in eradication of Helicobacter pylori in 50 to 80% of subjects. The aim of this investigator-blind crossover study was to determine if gastric mucosal amoxicillin uptake was affected by increasing gastric juice pH. Fifteen male subjects (7 H. pylori positive and 8 H. pylori negative) were randomized to receive 150 mg of ranitidine twice a day, 300 mg of ranitidine twice a day, or no drug for 2 days prior to upper endoscopy. The last dose of ranitidine was given 60 min prior to upper endoscopy, and amoxicillin (500 mg) was given 30 min prior to upper endoscopy. The amoxicillin concentrations in mucosal biopsy samples, gastric juice, and serum were determined by a standard microbiological bioassay technique. Mean amoxicillin levels were greater in samples of antrum, fundus, and duodenum for volunteers who received no ranitidine than in those receiving 300 mg of ranitidine (P < 0.05) and those receiving 150 mg of ranitidine (P < 0.05 except for fundus). Amoxicillin levels in the antrum, fundus, and duodenum were negatively correlated with gastric juice pH (P < 0.005 for antrum; P < 0.001 for fundus and duodenum). There was no correlation between gastric juice pH and amoxicillin levels in either gastric juice or serum. The amoxicillin concentration in gastric juice was significantly higher with 300 mg of ranitidine than with no ranitidine (P < 0.05). Thus, lower gastric juice pH is associated with a higher rate of mucosal uptake of amoxicillin.

Adolescent↗