Local cytokine response in Helicobacter pylori-infected subjects

The host immune response to Helicobacter pylori infection might be of importance with regard to the outcome of infection by this organism, e.g., to explain why only a proportion of infected subjects develop peptic ulcers. In this study we have analyzed the local response of different cytokines-i.e., the proinflammatory interleukin-1beta, (IL-1beta), IL-6, tumor necrosis factor alpha, and IL-8; the immunoregulatory gamma interferon (IFN-gamma); and IL-4; and the anti-inflammatory transforming growth factor beta (TGF-beta)-in antral biopsy specimens from H. pylori-infected duodenal ulcer (DU) patients and asymptomatic (AS) carriers (i.e., with chronic gastritis only). For comparison, biopsy specimens from uninfected healthy individuals were also analyzed. An immunohistochemical technique was used to allow quantification of the cytokine responses as well as identification of the cell types associated with the cytokine expression. We found that the levels of all of the studied cytokines except IL-4 were increased in the H. pylori-infected subjects compared to the levels in the healthy individuals. Our results indicate that the antral cytokine response is of the Th1 type since IFN-gamma, but not IL-4, was up-regulated both in H. pylori-infected DU patients and in AS carriers. However, there were no significant differences in either proinflammatory or immunoregulatory cytokine levels when H. pylori-infected subjects with and without peptic ulcers were compared. Some of the cytokines, particularly IL-1beta and TGF-beta, were also found in the gastric mucosae of healthy, uninfected subjects. We also showed that the gastric epithelium contributes substantially to the antral cytokine response of the proinflammatory cytokines IL-1beta and IL-6 in addition to IL-8.     

Relationship between local immune response to Helicobacter pylori and the diversity of disease: investigation of H. pylori-specific IgA in gastric juice

In order to evaluate the relationship between local immune response to Helicobacter pylori and the diversity of disease, 77 asymptomatic subjects who underwent a health examination were studied. Helicobacter pylori-specific IgG in serum and H. pylori-specific IgA in gastric juice were measured by ELISA, and the measured IgA titre was classified into two grades, low or high. Histological classification of gastritis was performed according to the Sydney system. Cytokines in gastric juice were also measured, and the cytotoxin-associated gene A (cagA) status of H. pylori was tested by PCR. Of the 65 subjects who were positive for H. pylori-specific IgG in serum, 38 (58.5%) were classified as H. pylori-specific IgA low titre in gastric juice and 27 (41.5%) had high titres. In the IgG-positive, IgA-low group, the rate of peptic ulcers (especially duodenal ulcers) in endoscopic findings was higher (P < 0.05); the score of activity and the density of H. pylori were higher (P < 0.001 and P < 0.05, respectively); the score of metaplasia was lower (P < 0.05); and the level of interleukin-1 beta was lower (P < 0.05) than in the IgG-positive, IgA-high group. The positive rate of the cagA gene was 84.4% and there was no significant difference between the two groups. There were differences in endoscopic and histological findings between the IgG-positive, IgA-low and the IgG-positive, IgA-high groups. It is suggested that persons infected with H. pylori can be divided into two different states of disease according to local immune response.     

Relationship of immune response to heat-shock protein A and characteristics of Helicobacter pylori-infected patients

This study assessed the minimum dose of clonidine required to prolong the duration of both anesthesia and analgesia after axillary brachial plexus blockade. Eighty patients scheduled for elective hand surgery were divided into eight groups in a randomized, double-blind fashion. An axillary brachial plexus block was performed with 40 mL 1% mepivacaine plus 1:200,000 epinephrine. The control group received no clonidine. In the other groups, increasing doses of clonidine (0.1, 0.2, 0.3, 0.4, 0.5, 1, and 1.5 micrograms/kg) were added to the local anesthetic solution. Onset time, duration of anesthesia and analgesia, postoperative pain score, intake of analgesics, and adverse effects were recorded. The eight groups were comparable in terms of onset time, postoperative pain score, and analgesic requirement. The minimum dose of clonidine required to significantly prolong the duration of analgesia and anesthesia was, respectively, 0.1 and 0.5 microgram/kg. No side effects (sedation, drowsiness, bradycardia, arterial hypotension) were reported. We conclude that the dose of clonidine required to prolong significantly the duration of both anesthesia and analgesia after axillary brachial plexus blockade is 0.5 microgram/kg and that, at this dose, clonidine may be used without important reported side effects even in outpatients.     

Isolation identification and quantitative culture of Helicobacter pylori from gastric mucosa

The biopsy specimens were homogenized and diluted ten-fold serially in Hank's solution. Each dilution samples were streaked on Skirrow's selective medium. The plates were incubated at 37 degrees C 5 to 7 days under micro-aerobic condition and counting the viable cell of H. pylori. The positive rate of specimens with H. pylori in active gastric ulcer tissue (62.0%) was higher than that in scarred tissue (51.9%). Number of H. pylori viable cells in active ulcer tissue was significantly larger than in scarred tissue. The positive correlation between Raw's gastritis score of specimens from patients with erosive gastritis and number of H. pylori viable cells was clearly noticed.     

Duodenal ulcer, Helicobacter pylori, and gastric secretion

Patients with chronic dyspepsia were categorised by macroscopic appearance at oesophagogastroduodenoscopy as having duodenal ulceration (DU), other diagnosed lesions such as reflux oesophagitis, carcinoma of stomach, etc, or no organic lesion (non-ulcer dyspepsia, NUD). Material was collected to identify gastric infection with Helicobacter pylori (H pylori) by CP urease test, culture, and histological examination and to make the microscopic diagnosis of active chronic gastritis. Each patient in the DU and NUD categories was then invited to volunteer for a gastric secretion study in which maximal gastric secretion in response to histamine was measured. Sixty two gastric secretion tests were performed (31 DU, 31 NUD). The presence of H pylori was associated with active chronic gastritis (100%). DU patients secreted more acid than the NUD patients. H pylori positivity was associated with decreased maximal gastric secretion in both groups. There was a positive correlation between smoking and maximal acid output shown only in H pylori negative but not in H pylori positive patients. These findings were clear cut when all corrections of maximal gastric secretion were made for pyloric loss, duodenogastric reflux, and stature. This study failed to show any aetiological link between H pylori and DU by increased maximal gastric secretion.     

Helicobacter pylori, gastric pathology, and histopathological diagnosis

Structural analogues of ZAPA, Z-3-[(aminoiminomethyl)thio]prop-2-enoic acid, an isothiouronium analogue of GABA, are potent GABAA agonists as seen in the isolated guinea-pig ileum and in the facilitation of [3H]diazepam binding to rat brain membranes. Compounds with guanidino or amidine groups replacing the amino functionality of GABA were also found to be active. The highest activity was displayed by the isothiouronium salts in which the conformational flexibility of the molecule is restricted by a Z-substituted carbon-carbon double bond. A series of bis-isothiouronium compounds was prepared from aliphatic alpha, omega-bis-thioureas as mixtures of E and Z adducts. Maximum GABAA agonist activity for this series was found with a C6-C8 carbon chain, and the results were consistent with an interaction at the GABAA receptor with only one end of the molecule, rather than the more potent effect expected of a molecule bridging two active sites. GABAA antagonist/partial agonist activity was observed on the guinea pig isolated ileum for a number of different analogue types, with the most potent being bis-isothiouronium derivatives. None of the substituted derivatives of ZAPA was as active as ZAPA itself, and maximum GABAA activity was found in the n-pentyl and n-hexyl analogues.     

Analysis of cell damage and proliferation in Helicobacter pylori-infected human gastric mucosa from patients with gastric adenocarcinoma

Helicobacter pylori (HP) infection, a cause of multifocal atrophic gastritis, is considered an important factor related to the evolution of the human gastric mucosa from normal to intestinal-type adenocarcinoma. We examined cell proliferation and both double and single strand DNA damage in situ in 35 patients undergoing gastrectomy for adenocarcinoma with HP-infected gastric mucosa by immunolocalization of Ki-67, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling, and in situ nick translation. We also studied the distribution of intraepithelial neutrophils by elastase immunolocalization. HP infection was confirmed in all cases by serum anti-HP antibodies, ureas testing, and histopathological examination. HP-infected gastric mucosa was classified according to the degree of inflammation and intestinal metaplasia. Ki-67, terminal deoxynucleotidyl transferase-mediated labeling, in situ nick translation, and intraepithelial neutrophil indices all increased with the progression of gastritis and were highest in glands with incomplete intestinal metaplasia. All indices were lowest in gastric glands with complete intestinal metaplasia. Significant positive correlations were observed among these markers. Increased proliferative activity in HP-associated chronic gastritis in response to cell damage or injury was clearly demonstrated, suggesting that both HP-associated toxins and intraepithelial neutrophils are important in HP-related gastric epithelial injury. Increased cell turnover associated with incomplete intestinal metaplasia may result in DNA instability and subsequent development of intestinal-type gastric adenocarcinoma in HP-infected mucosa.     

Helicobacter pylori infection, gastric acid secretion, and infant growth

BACKGROUND: Helicobacter pylori infection is very common in Gambian infants and children, who are also at risk of chronic diarrhoea and undernutrition. Acute H. pylori infection is associated with depressed gastric acid secretion, and loss of the gastric acid barrier may predispose to enteric infections. METHODS: In a prospective study a noninvasive test of gastric acid output (measurement of change in urine acid output before and after a feed) was performed on a population of Gambian infants at high risk of H. pylori infection. The 13C urea breath tests was used to measure the prevalence of H. pylori infection and growth was measured by serial anthropometry. RESULTS: In 101 infants aged 3 to 12 months, there was a significant relation between H. pylori infection and depressed urine acid output in those aged 6 months, during weaning when growth failure and malnutrition begin. Those infants with sustained H. pylori infection grew less well than those without. CONCLUSIONS: We speculate that H. pylori, acquired in infancy, could be a "key that opens the door" to enteric infection in childhood, leading to recurrent diarrhoea, malnutrition, and growth failure.     

Functional dyspepsia, gastric emptying of solids, and Helicobacter pylori infection

The origin of functional dyspepsia (FD) is unknown, however, abnormal gastric emptying and infection by H. pylori have been suggested as possible causes. OBJECTIVE: The aim of this study was to test the hypothesis that infection by H. pylori could be related to alterations in gastric emptying of solids and play a role in the pathophysiology of dyspepsia. METHODS: Studies were performed on 12 controls: 6 males, 6 females, age 40 +/- 13, and on 45 FD patients: 15 males and 30 females, age 43.5 +/- 12. Clinical criteria for FD diagnosis were post-prandial epigastric pain, nausea, vomiting or epigastric bloating, with normal blood test, upper endoscopy and abdominal ultrasound. Diagnosis of H. pylori infection was either by growth positive on culture of antral biopsy or by all of the following: on Gram stain, urease test positive and visualization of microorganisms in the antral biopsy. Gastric emptying of solids was studied with a radio-nuclide technique. Patients were prospectively classified in 4 groups according to the main symptom: reflux-like, ulcer-like, dysmotility, and non-specific. RESULTS: H. pylori infection was observed in 21/32 (66%) FD patients. No significant differences in the gastric emptying of solids between the control group and patients with FD (tl/2 80 +/- 17 minutes vs 75 +/- 16 min). The presence of H. pylori infection did not influence gastric emptying rates (78 +/- 16 minutes in infected patients vs 73 +/- 15 min in non infected patients). Gastric emptying times were similar among the four subgroups of FD patients. CONCLUSIONS: No significant differences in gastric emptying of solids were found in H. pylori infected persons as compared with the controls. These findings suggest that H. pylori infection and/or changes in gastric emptying of solids do not play a role in the pathophysiology of FD.     

Helicobacter pylori and non-Helicobacter pylori bacterial flora in gastric mucosal and tumour specimens of patients with primary gastric lymphoma

There is an association between Helicobacter pylori (H. pylori) and gastric mucosa-associated lymphoid tissue (MALT) and MALT lymphoma. Histologically, mainly non-specific stains are used to detect H. pylori, such as haematoxylin-eosin (HE) or modified Giemsa (MG). In this study, both a MG and a specific immunohistochemical stain (IMM) for H. pylori (Dako B471) were performed on sequential slides of resected material containing tumour and non-tumorous gastric mucosa from patients with primary gastric lymphoma (n = 52). Special attention was paid to the presence of non-H. pylori bacterial flora diagnosed by a positive MG (according to form and localization) and a subsequently negative IMM. On all slides, bacterial density was scored semiquantitatively (grades 0, 1, 2, 3). In total, 32 (61.5%) patients were H. pylori positive using IMM and 34 (65.4%) were non-H. pylori positive using MG. In 24 out of the 34 patients, the non-H. pylori flora consisted mainly of cocci in combination with rods in 15 patients, mostly in minor quantities; in another 10 patients, high numbers of both cocci and different types of rods were present. Most non-H. pylori bacteria were localized superficially, although in 22 patients minor quantities of non-H. pylori were also seen in the glandular lumina. After all of the patients had been analysed, no differences in the density of H. pylori and of non-H. pylori flora were found. Only when comparing patients who had a small-cell lymphoma with those who had a large-cell lymphoma was a significantly higher density of H. pylori found in the corpus mucosa of large-cell lymphomas and a higher prevalence of non-H. pylori was found in tumours, in antrum or corpus, of patients with large-cell lymphomas. In conclusion, with joint evaluation using MG and a H. pylori-specific immunohistochemical stains, the proportion of H. pylori-positive gastric lymphoma patients was lower than in most previous studies but other bacteria were found in a relatively high proportion. The role of the non-H. pylori intragastric bacterial flora identified in this study has to be further elucidated in the aetiopathogenesis of primary gastric lymphoma.     

Prevalence and pattern of Helicobacter pylori gastritis in the gastric cardia

OBJECTIVES: Helicobacter pylori has a predilection for antral colonization. Local acid production is the major determinant of colonization. Because production is low in the antrum and cardia, H. pylori should also colonize the cardia. We therefore investigated the histologic pattern of gastritis and the prevalence of H. pylori in the cardia compared with the antrum and corpus. METHODS: From 135 H. pylori-infected patients with gastritis, ulcer disease, or reflux esophagitis, biopsies were obtained from the antrum, corpus, and cardia. The prevalence, topography, and histologic parameters of gastritis were examined. RESULTS: All 135 patients had active antral H. pylori gastritis: in the cardia, 132 of these patients (97.7%) showed active gastritis, and 124 patients (91.9%) had H. pylori visible on staining. Gastritis of the cardia in most patients resembled antral gastritis, but the density of bacteria and the inflammatory responses were less marked. The most striking finding in the cardia of patients with gastroesophageal reflux was a lower density of bacteria compared with antrum and corpus. Intestinal metaplasia was found in 32 patients in antral mucosa (23.7%) versus 28 patients in the cardia (20.7%), versus 11 patients in the corpus (8.1%), and was multifocal in 17 patients (12.6%). CONCLUSIONS: H. pylori gastritis commonly involves the cardia. The histologic density of the bacteria and inflammatory responses are lower than in the antrum. Intestinal metaplasia in the cardia is a common finding in H. pylori gastritis. The cause of the lower bacterial density in the cardia of patients with reflux esophagitis needs further investigation.     

Influence of Helicobacter pylori on gastric secretion. Study on variously associated gastric body, fundus and antrum chronic gastritis

Among the various themes related to Helicobacter pylori (HP) which is still a subject of discussion, there is the possible influence of this bacterium on gastric secretory physiology. In the present study, an evaluation has been carried out of stimulated gastrinemia, stimulated acid secretion and total peptic activity in gastric juice in the course of a paradigmatic condition, as autonomous chronic gastritis, in order to reveal possible modifications induced by the HP infection. In cases of HP positive chronic superficial antral gastritis associated either with normal body-fundic mucosa or with superficial gastritis, there is a significant increase of stimulated gastrinemia in comparison to HP negative groups and controls. In the course of body-fundic atrophic and preatrophic chronic gastritis associated either with antral superficial chronic gastritis or with antral atrophic gastritis, there are no statistically significant differences between HP positive and HP negative subjects. As regards acid and pepsin secretion no significant differences emerge in any group between HP positive and HP negative subjects. In the HP positive subjects with antral superficial gastritis and higher gastrin values the study of acid and pepsin secretion has yielded no significant variations. From the results of this study it emerges how gastric secretory parameters vary exclusively according to the histologic state of gastric mucosa. Therefore, the lesion action of HP may mainly be attributed to a direct action, rather than to substantial gastric secretory changes.     

Changes in gastric mucosa and Helicobacter pylori infection in young health volunteers

The effect of microinjection of a GABAB receptor agonist, baclofen, into the ventral tegmental area on the rewarding effect of morphine was investigated using the conditioned place preference paradigm in rats. Morphine (1-8 mg/kg, s.c.) caused a dose-related place preference for the drug-associated place. In contrast, microinjection of baclofen (0.1-1 nmol/side) into the ventral tegmental area did not produce a significant preference for either compartment of the test box. Pretreatment with baclofen (0.1-1 nmol/side) into the ventral tegmental area dose dependently suppressed the morphine (8 mg/kg, s.c)-induced place preference. This suppression of the morphine (8 mg/kg, s.c.)-induced place preference by baclofen (1 nmol/side), but not with the GABAA receptor antagonist bicuculline (1 nmol/side). The present results suggest that a decrease in GABAB neurotransmission in the ventral tegmental area, which may be produced via inhibition of a tonic GABAergic input by morphine, may be involved in the expression of the rewarding effect of morphine.     

Prevalence of Helicobacter pylori infection and gastric mucosal abnormalities in chronic pancreatitis

OBJECTIVE: Chronic pancreatitis is often associated with abnormal gastric acid secretion. However, previous studies have taken into consideration neither the potential role of Helicobacter pylori (H. pylori) infection nor histological features of the gastric mucosa in this context. The aim of this study was to analyze the prevalence of H. pylori infection as well as the pattern of gastritis in patients with chronic pancreatitis. METHODS: Forty patients with chronic alcoholic pancreatitis were included in the study: 40 patients with alcoholic liver cirrhosis and normal exocrine pancreatic function and 40 asymptomatic nonalcoholic subjects matched for age and sex used as control subjects. Endoscopy was performed in all patients, and five biopsy specimens from the antrum (three from the gastric body and two from the cardia) were taken for histological grading of gastritis and H. pylori assessment. RESULTS: Prevalence of H. pylori infection was similar in subjects with chronic pancreatitis (38%), asymptomatic subjects (28%) and liver cirrhosis (30%). Topography and expression of H. pylori-associated chronic gastritis was also not different among the three groups of subjects. In H. pylori-negative subjects, the presence of moderate to severe chronic antral gastritis was significantly more common in patients with chronic pancreatitis (40%) than in subjects with liver cirrhosis (18%) and in asymptomatic subjects (14%) (p < 0.05). No difference was found among the three groups of patients with regard to gastritis activity, atrophy, and intestinal metaplasia in the various gastric regions. The chronicity grade of gastritis did not correlate with the severity of pancreatic insufficiency. CONCLUSION: Prevalence of H. pylori infection is not different in patients with chronic pancreatitis as compared with subjects alcoholic liver cirrhosis and asymptomatic subjects. A severe H. pylori-negative chronic gastritis is more common in patients with chronic pancreatitis. This chronic inflammation of the gastric mucosa could contribute to determining the changes in gastric physiology described in patients with chronic pancreatitis.     

Relevance of Helicobacter pylori infection in the development of gastric tumors

The efficacy of a 6-week rehabilitation program was evaluated in 100 consecutive patients, age 15-42 years, with acute anterior cruciate ligament (ACL) injury. Arthroscopy revealed associated lesions in 82% of the patients. Except for resections on menisci with large and unstable lesions, no surgery was performed. The patients were randomly assigned to supervised training or self-monitored training after instruction. RESULTS: At the 6-week follow-up there was no difference between the groups with regard to pain at rest, pain during walking, or experience of giving-way episodes, Tegner activity level of Lysholm knee score. Only 2 of the 100 patients were observed without joint mobility restriction. The only significant difference between the groups was the improvement of muscle function in men in the supervised training group. Conclusion: Six weeks' rehabilitation is too short a time period from original injury to obtain normal mobility and restored knee function.     

Isolation and identification of Helicobacter spp. from canine and feline gastric mucosa

It is known that virtually all healthy adult dogs and cats harbor spiral helicobacters in their gastric mucosa. Three species, Helicobacter felis, Helicobacter bizzozeronii, and Helicobacter salomonis have been isolated in vitro from the gastric mucosa of these animals. The aims of this study were to evaluate the efficacy of an isolation method for canine and feline gastric helicobacters that has been developed at the University of Helsinki; to estimate the prevalence and distribution of these taxa in the samples examined; and to assess the efficacy and validity of an extensive set of standardized conventional phenotypic tests, whole-cell protein profiling, and ultrastructural analysis in identifying the different species isolated from canine and feline gastric mucosa. We cultured 95 and 22 gastric mucosal biopsies from dogs and cats, respectively. Twenty-one H. bizzozeronii strains, 8 H. felis strains, 8 H. salomonis strains, 3 mixed cultures, 2 "Flexispira rappini"-like organisms, and 3 as yet uncharacterized strains were isolated from the dogs, and 3 H. felis strains were isolated from the cats. The methods used here yielded Helicobacter isolation rates of 51% from dogs and 13.6% from cats, which exceed those reported previously. The main difficulties were primary isolation, mixed cultures, and identification to the species level. In the species identification, a detailed morphological examination was found to yield important phenotypic characteristics. A large panel of biochemical and tolerance tests did not clearly differentiate the closely related species H. bizzozeronii, H. felis, and H. salomonis. Highly standardized whole-cell protein profiling was shown to be an excellent method for species identification. Improvements in culture conditions for these bacteria are still needed, especially for cats. A genetic identification method not requiring culture is needed for future studies of these very fastidious helicobacters, as the clinical significance and ecology of these species within the gastric mucosa of the domestic carnivores remain largely unknown.     

Possible role of Helicobacter pylori infection in early gastric cancer development

BACKGROUND: Gastric cancer is the most frequently diagnosed malignancy in Japan. The possible relationship between Helicobacter pylori infection and gastric cancer in Japan was evaluated. METHODS: H. pylori infection was identified by the presence of anti-H. pylori IgG. The frequency of H. pylori infection was compared in 213 patients with gastric cancer and the same number of asymptomatic control subjects matched for age and sex. RESULTS: The presence of IgG antibody to H. pylori was significantly more prevalent (P < 0.001) in those with gastric cancer compared with asymptomatic control subjects (88.2% versus 74.6%). H. pylori positive rates were significantly greater in patients with the intestinal type (90.4%, P < 0.001) and diffuse type (86.4%, P < 0.05) of gastric cancer than in control subjects. Ninety-three percent of the patients with early gastric cancer tested positive for H. pylori (P < 0.001 compared with control subjects), whereas no significant difference was observed between those with advanced gastric cancer and control subjects. The intestinal type of early gastric cancer showed only the significantly increased frequency of high titer (optical density > 1.50) of H. pylori IgG antibody (P < 0.001) compared with control subjects without cancer. CONCLUSIONS: These results suggest that H. pylori infection may be associated with the development of early gastric cancer in Japan.     

Molecular alterations in early gastric carcinomas. No apparent correlation with Helicobacter pylori status

The effect of nitric oxide (NO) donors on high-voltage-activated Ca2+ channels in insulin-secreting RINm5F cells was investigated using the patch-clamp technique in the whole-cell configuration. Sodium nitroprusside (SNP, 2-400 microM) induced a dose-dependent reduction in Ba2+ currents with maximal inhibition of 58%. The IC50 for SNP was 45 microM. A different NO donor, (+/-)S-nitroso-N-acetylpenicillamine (SNAP, 500 microM), also produced a 50% decrease in current amplitude. When 200 microM SNP was administered together with the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidozoline-1-oxyl-3-oxide (carboxy-PTIO, 300 microM), the Ba2+ current inhibition was lowered to 7%. Administration of 500 microM 8-bromoguanosine 3':5'-cyclic monophosphate sodium salt (8-Br-cGMP) mimicked the effects of SNP, causing a comparable decrease (56%) in peak-current amplitude. When soluble guanylyl cyclase was blocked by 10 microM 1H-[1,2, 4]oxadiazole[4,3-a]quinoxalin-1-one (ODQ), the inhibitory effect of 200 microM SNP was reduced from 39% to 15%. The SNP-induced current decrease was 36% of controls after the blockade of L-type Ca2+ channels and 30% in the presence of 2.5 microM omega-conotoxin-MVIIC. These data indicate that NO inhibits both L-type and P/Q-type Ca2+ channels in RINm5F cells, probably by an increase in the intracellular levels of cGMP. NO may then significantly influence the Ca2+-dependent release of hormones from secretory cells as well as that of neurotransmitters from nerve terminals.