Incidence of Chlamydia pneumoniae infection in patients with coronary artery disease subjected to angioplasty or bypass surgery

BACKGROUND

Seroepidemiological, pathological and animal studies suggest that chronic infection with Chlamydia pneumoniae (Cp) may directly impact the development or progression of atherosclerosis and coronary heart disease. The aim of the present study was to determine the seroprevalence of Cp infection and markers of systemic inflammation in patients undergoing routine coronary artery examination and prior to heart revascularization.

MATERIAL AND METHODS

The research involved 76 patients with severe CAD and 81 control patients with normal coronary circulation confirmed by coronary angiography. The presence of serum IgG and IgA antibodies to Cp and plasma interleukin-8 (IL-8) levels was measured by EIA test. Furthermore, the levels of plasma C-reactive protein, fibrinogen, total cholesterol, and triglycerides were measured in all patients.

RESULTS

Seropositivity to Cp was found in 60.5% for IgG and in 61.8% of cases for IgA with CAD patients, as compared to 26.0% and 29.5% in the controls (p<0.001), respectively. The levels of Interleukin-8, plasma fibrinogen, total cholesterol and triglycerides were significantly higher (p<0.001) in the CAD group, while C-reactive protein tended to have a higher value in patients with atherosclerosis than in the control group, although the difference was not significant.

CONCLUSIONS

Cp infection significantly increases the risk of CAD, usually requiring coronary bypass surgery or percutaneous coronary intervention as effective measures. It may also modify the levels of serum lipids, CRP and fibrinogen, increasing the risk of atherosclerosis. The strong correlation between the elevated IgG and IgA titers of Cp in patients treated with angioplasty or surgery may impact their follow-up; this issue requires further investigation.

Helicobacter pylori infection, gastrin, cyclooxygenase-2, and apoptosis in colorectal cancer

Helicobacter pylori (HP) infection is usually accompanied by an increased plasma level of gastrin, a potent mitogen able to induce cyclooxygenase (COX)-2. This study examined (a) the seroprevalence of HP, its cytotoxic protein, CagA, and cytokines (tumor necrosis factor alpha, interleukins 1beta and 8) in 80 patients with colorectal cancers, before and after the removal of tumor, compared with 160 age- and gender-matched controls; (b) the gene expression of gastrin and its receptors (CCKB-R) in the cancer tissue, (c) the plasma levels and tumor tissue contents of gastrin, and (d) the mRNA expression of COX-1, COX-2, and apoptotic proteins (Bax and Bcl2) in cancer tissue and intact colonic mucosa. Anti-HP IgG, anti-CagA IgG seroprevalence, and cytokine levels were analyzed by enzyme-linked immunosorbent assay tests; gene expressions of gastrin, CCKB-R, COX-1, COX-2, Bax, and Bcl2 by reverse transcriptase polymerase chain reaction; and gastrin by radioimmunoassay. The seroprevalence of HP, especially that expressing CagA, was significantly higher in cancer patients than in controls and did not change 1 week after tumor resection while plasma cytokines were significantly reduced after this operation. Both gastrin and CCKB-R mRNA were detected in the cancer tissue and the resection margin; similarly, COX-2 mRNA was expressed in most of cancers and their resection margin but not in intact colonic mucosa, where only COX-1 was detected. The colorectal cancer tissue contained several folds more immunoreactive gastrin than cancer resection margin and many folds more than the intact colonic mucosa. We conclude that colon adenocarcinoma and its resection margin overexpress gastrin, its receptors, CCKB-R, and COX-2, and that HP infection may contribute to colonic cancerogenesis via overexpression of gastrin and COX-2, which may account for the stimulation of the tumor growth and the reduction in apoptosis as documented by enhanced mRNA expression of anti-apoptotic Bcl2 over proapoptotic Bax proteins.

Expression of hepatocyte growth factor, transforming growth factor alpha, apoptosis related proteins Bax and Bcl-2, and gastrin in human gastric cancer

BACKGROUND

Gastric cancer is one of the most frequent neoplasms and a leading cause of the death world-wide. In recent years, epidemiological and animal studies demonstrated a link between gastric cancer and chronic infection with H. pylori. The exact mechanism responsible for the development of gastric cancer in H. pylori-infected patients still remains unclear. There is evidence that the up-regulation of certain growth factors could play an important role in the promotion of the gastric carcinogenesis.

AIMS

The present study was designed to determine the gene expression of major known growth factors such as transforming growth factor alpha (TGFalpha), hepatocyte growth factor (HGF) and gastrin in the gastric cancer tissue, the surrounding mucosa and, for comparison, in the normal gastric mucosa. Furthermore, the luminal and plasma levels of gastrin in patients with gastric cancer were determined. In addition, the gene and protein expressions of apoptosis-related proteins such as Bax and Bcl-2 were investigated by reverse transcription-polymerase chain reaction and Western blot. Twenty-five gastric cancer patients and 40 age- and gender-matched control subjects hospitalized with non-ulcer dyspepsia were included into this study.

RESULTS

An overall H. pylori-seropositivity among gastric cancer patients was about 72% and was significantly higher than in the controls (56%). The prevalence of CagA-positive strains was also significantly higher among gastric cancer patients than in controls (56% vs. 32%). The gene expression of HGF and TGFalpha was detected more frequently in gastric cancer tissue samples than in normal gastric mucosa (52% vs. 12% for HGF and 48% vs. 24% for TGFalpha). The extent of protein expression in Western blotting analysis for HGF and TGFalpha correlated with the mRNA expression of these factors. Gene expression of gastrin was detected in the antrum of all tested patients and in the majority (84%) of gastric cancer patients. The median plasma and luminal concentrations of gastrin in gastric cancer patients were significantly higher than in controls. The gene expression of bcl-2 was detected in all (100%) and that of proapoptotic bax only in 56% of gastric cancer samples. In comparison to the surrounding non-tumorous tisssue, the gene expression of bax was significantly down-regulated and the gene expression of bcl-2 was up-regulated in gastric cancer tissue. At the protein level, Bax was not detectable and Bcl-2 was seen in 80% of gastric cancer samples.

CONCLUSIONS

It is concluded that the patients infected with H. pylori, especially with CagA-positive strains, are at a higher risk of developing a gastric cancer. An increased production and release of gastrin, as well as an over-expression of growth factors such as HGF and TGFalpha, might contribute to the gastric carcinogenesis. In addition, a dysregulation of the Bax/Bcl-2 system with significant up-regulation of Bcl-2 is observed in gastric cancer.

Prevalence of Helicobacter pylori infection in coronary artery disease and effect of its eradication on coronary lumen reduction after percutaneous coronary angioplasty

BACKGROUND

Gastric infection caused by Helicobacter pylori has recently been associated with increased risk of coronary artery disease.

AIM

To: 1) determine seroprevalence of Helicobacter pylori and its cytotoxin associated gene A in patients with/without coronary artery disease (group A), 2) assess influence of Helicobacter pylori eradication on coronary artery lumen reduction after percutaneous coronary angioplasty (group B) and 3) determine influence of Helicobacter pylori eradication on plasma cytokines, lipids and coagulation factors in patients subjected to percutaneous coronary angioplasty (group B).

PATIENTS AND METHODS

Group A included 100 patients with coronary artery disease (subgroup 1) and 100 patients without (subgroup II). For Helicobacter pylori seroprevalence, plasma anti-Helicobacter pylori and anti-cytotoxin associated gene A IgG were examined. Group B included 40 patients with significant single-vessel coronary arterial disease and Helicobacter pylori infection confirmed by 13C-urea breath test and serologically using anti-Helicobacter pylori and anti-cytotoxin associated gene A IgG. Six months after percutaneous coronary angioplasty and triple anti-Helicobacter pylori therapy, the Helicobacter pylori status reassessed by urea breath test was negative in all but two patients of subgroup I subjected to Helicobacter pylori therapy. Coronary angiography and laboratory tests were repeated in both subgroups of group B included in the trial and reduction in coronary artery lumen in these subgroups was compared to baseline after percutaneous coronary angioplasty considered as 100%.

RESULTS

Helicobacter pylori seropositivity reached 81.5% of coronary artery disease (subgroup I) and was significantly higher than that in controls without coronary artery disease (subgroup II) (51%), the odds ratio being 4.3 for Helicobacter pylori in coronary artery disease. Cytotoxin associated gene A IgG detection was also significantly higher (47.3%) in coronary artery disease than in controls (28%) giving the odds ratio about 2.3. Mean coronary artery lumen reduction in patients undergoing percutaneous coronary angioplasty + Helicobacter pylori eradication therapy (subgroup I) was significantly (p<0.05) smaller compared to percutaneous coronary angioplasty + placebo-treated subgroup II (22% vs 41%).

CONCLUSIONS

1) There is a significant link between coronary artery disease and infection with Helicobacter pylori, especially expressing CagA proteins, 2) Helicobacter pylori eradication significantly attenuates reduction in coronary artery lumen in coronary artery disease patients after percutaneous coronary angioplasty possibly by elimination of chronic inflammation and decline in proinflammatory cytokine release, and 3) Infection of Chlamydia pneumoniae in these percutaneous coronary angioplasty patients is not affected by eradication therapy.

Water extracts of Helicobacter pylori suppress the expression of histidine decarboxylase and reduce histamine content in the rat gastric mucosa

BACKGROUND

Acute Helicobacter pylori (Hp) infection in humans may be associated with markedly reduced gastric acid secretion, but the mechanism of this hypochlorhydria has not been fully explained.

AIMS

This study was designed to investigate how water extracts (WE) of Hp applied on rat gastric mucosa affect gastric secretion and mucosal histamine concentration as well as the gene expression for histamine decarboxylase (HDC), the key enzyme converting histidine to histamine and for interleukin-1beta (IL-1beta), the important proinflammatory cytokine.

MATERIALS AND METHODS

Wistar rats were surgically equipped with small cannulas to form gastric fistulas (GF). Four weeks after formation of GF, rats received either saline (control group) or WE obtained from type I Hp strain expressing CagA/VacA proteins and from type II Hp strain negative for CagA/VacA. Hp-WE was applied intragastrically (i.g.) in a volume of 1 ml at days 0, 2, 4 and 6 (total 4 times). At days 7 and 14, the secretory tests were performed during which basal gastric acid and pepsin secretion was examined and acid and pepsin outputs were measured. After secretory tests, the rats were sacrificed, the stomachs removed and the damage to the gastric mucosa was assessed by measuring the lesion area planimetrically and by histology, the gene expression in gastric mucosa for HDC and interleukin-1beta (IL-1beta) was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) and Southern blot. Additionally, somatostatin concentration in gastric juice, gastric mucosal histamine content and plasma gastrin and IL-1beta levels were determined using radioimmunoassay (RIA).

RESULTS

Administration of Hp-WE failed to induce gross mucosal damage but microscopic examination revealed partial denudation of gastric surface epithelium without causing deep necrosis. In secretory tests, Hp-WE produced marked hypochlorhydria but type I Hp-WE induced significantly stronger inhibition of acid and pepsin secretion than type II Hp-WE, both at days 7 and 14. Both, type I and type II Hp-WE suppressed significantly the gene expression for HDC mRNA and lowered significantly gastric mucosal histamine content as compared to respective values in vehicle-treated control gastric mucosa. Furthermore, Hp-WE, resulted in a significant increase in expression of IL-1beta mRNA and a significant fall in luminal somatostatin concentration as well as a insignificant elevation of plasma gastrin level, the type I Hp-WE being more effective in these alterations than type II Hp-WE.

CONCLUSIONS

(1) Ability of Hp-WE to induce superficial damage, the reduction in HDC mRNA and accompanying fall in gastric histamine release, contribute, at least in part, to marked hypochlorhydria observed in the stomach exposed to repeated Hp-WE treatments, and (2) the deleterious effect of Hp-WE on the gastric mucosa involves an impairment of gastrin-somatostatin link possibly resulting from the action of Hp-derived toxins and the induction in mucosal cells of proinflammatory cytokine such as IL-1beta.

Helicobacter pylori, gastrin and cyclooxygenases in gastric cancer

BACKGROUND

Tumors arising in the stomach have worldwide distribution and the infection with Helicobacter pylori (HP) has been implicated in causation of this disease. The HP discovery, which is considered as the greatest advance of gastroenterology at the dawn of 3rd millennium, is accompanied by hypergastrinemia, which seems to play a key role in gastric cancerogenesis but no study was undertaken to assess the relationship between the HP infection and coexpression of gastrin and cyclooxygenases (COX), the rate limiting enzymes in the eicosanoids production.

AIMS

Since gastrin is recognized as a effective gastric mitogen, it could be capable to induce COX-2, a potent tumor growth promoting and angiogenic factor, we decided 1) to compare the seroprevalence of HP and its cytotoxic protein, CagA, in gastric cancer patients with those in age- and gender-matched controls; 2) to determine the gene expression of gastrin and its receptors (CCK(B)-R) in gastric cancer, 3) to assess the plasma levels, gastric lumen and tumor tissue contents of gastrin and 4) to examine the mRNA and enzyme protein expression of COX-1 and COX-2 in cancer tissue and intact gastric mucosa before and after HP eradication.

MATERIAL AND METHODS

The trial material included 20 patients with gastric cancers and 100 age- and gender-matched controls. Anti-HP and anti-CagA IgG seroprevalence was estimated by specific antisera using ELISA tests. Gene expressions of gastrin, CCK(B)-R, COX-1 and COX-2 was examined using RT-PCR with GAPDH as a reference and employing Western blot for COX-2 expression, while gastrin was measured by RIA.

RESULTS

The seroprevalence of HP, especially that expressing CagA, was significantly higher in gastric cancers than in controls. Both gastrin and CCK(B)-R mRNA were detected by RT-PCR in the cancer tissue and similarly COX-2 mRNA and protein were found in most of cancers and in the HP infected antral mucosa but not in HP eradicated patients in whom only cancer tissue but not gastric mucosa expressed COX-2. The gastric cancer tissue contained 20 times more of immunoreactive gastrin than the HP infected antral gastric mucosa and following HP eradication the gastrin content in the tumor and antrum showed a marked and significant reduction. No significant change in CCK(B)-R expression was noticed before and after HP eradication in the tumor and the corpus mucosa.

CONCLUSIONS

1). Gastric carcinoma coexpresses gastrin, its receptors (CCK(B)-R), and COX-2; 2) HP infection may contribute to gastric cancerogenesis via gastrin andCOX-2 that may account for the stimulation of tumor growth, angiogenesis, and reduction in apoptosis 3) HP positive patients developing gastric cancer should be considered for HP eradication to reduce the HP provoked hypergastrinemia and COX-2 overexpression in the tumor tissue.

Helicobacter pylori infection delays healing of ischaemia-reperfusion induced gastric ulcerations: new animal model for studying pathogenesis and therapy of H. pylori infection

OBJECTIVE

Helicobacter pylori (Hp) infection is a major risk factor of peptic ulcerations but studies on its pathogenicity are limited due to the lack of an adequate animal model. In this study we developed the new model of gastric Hp infection in rat gastric mucosa, with acute gastric erosions progressing into ulcers in animals subjected initially to ischaemia-reperfusion (I/R).

DESIGN

I/R lesions were produced in rats by clamping the coeliac artery for 0.5 h followed by 1 h reperfusion and gastric inoculation with type I Hp strain (CagA and VacA positive) or type II Hp strain (CagA and VacA negative), obtained from fresh clinical isolates, or with vehicle (saline). Gastric secretion during recovery from I/R lesions was determined in a separate group of rats equipped with chronic gastric fistula to inoculate the animals with Hp and then to collect gastric juice for determination of gastric acidity and pepsin outputs as well as luminal content of somatostatin.

METHODS

The animals were killed at 0, 3, 12 or 24 h and 3, 5, 10 or 15 days after Hp inoculation and the area of gastric lesions was determined planimetrically and gastric blood flow (GBF) was measured by the H2-gas clearance technique. The venous blood was withdrawn for measurement of plasma interleukin (IL)-1beta and tumour necrosis factor alpha (TNFalpha) by ELISA and plasma gastrin, luminal somatostatin by RIA and the mucosal expression of transforming growth factor (TGFalpha) was analysed using RT-PCR with specific primers. Gastric Hp infection was assessed by histology, rapid urease test and Hp culture. The effect of triple therapy with omeprazole, amoxycillin and tinidazole on Hp infection and ulcer healing was also determined.

RESULTS

Ischaemia alone resulted in an immediate fall in GBF and almost complete suppression of gastric secretion but without any gastric lesions. When ischaemia was followed by 1 h of reperfusion, acute gastric erosive lesions immediately occurred, reaching a maximum at 12 h after I/R and progressing after 3 days to deeper gastric ulcers that disappeared after 15 days. In Hp-inoculated rats, the number of viable Hp colonies gradually increased, reaching maximum at day 10 with infection with type I and at day 15 with infection with type II Hp. At day 15 the difference in Hp colonization was not significantly different between the stomachs infected by type I and type II Hp. Inoculation, especially with the type I Hp strain, significantly delayed healing of I/R-induced acute lesions and accelerated their progression into deeper chronic ulcers. This effect was accompanied by a significant fall in GBF and a higher increment in plasma IL-1beta and TNFalpha levels. Gastric acid secretion, which was completely inhibited up to 12 h after I/R, returned to the control value 24 h upon completion of the I/R procedure. This return was delayed in Hp-infected rats and accompanied by a significant elevation of plasma gastrin and a decrease in luminal somatostatin. The immunoreactivity of TGFalpha and expression of TGFalpha mRNA determined by RT-PCR were well defined in intact gastric mucosa but were significantly decreased, especially in mucosa infected with type I Hp strain, at day 15 after I/R. The triple therapy which cured Hp infection completely abolished the delay in ulcer healing caused by Hp.

CONCLUSIONS

(1) Gastric infection with the Hp strain expressing cagA and vacA encoded cytotoxins delays healing of I/R-induced acute gastric lesions due to an impairment of gastric microcirculation, and excessive proinflammatory cytokine release and suppression of anti-ulcer TGFalpha expression. (2) The I/R induced suppression of gastric acid secretion may contribute to the hypergastrinaemia as a secondary phenomenon and may account for the spread of Hp infection observed during the progression of acute erosions into chronic ulcers. (3) I/R induced gastric ulcers may be a useful model for studying the action of Hp infection on gastric ulcerogenesis in ischaemic stomach and for testing anti-Hp therapy.

Helicobacter pylori-gastrin link in MALT lymphoma

BACKGROUND

There is accumulating evidence for the role of Helicobacter pylori in the development of gastric cancer as well as of lymphomas that arise in mucosa-associated lymphoid tissue (MALT). We reported recently that gastric cancer patients show high prevalence of cagA-positive H. pylori and express gastrin and gastrin receptors enabling them to stimulate tumour growth in autocrine fashion.

AIMS

Since the H. pylori infection is considered to be more strongly associated with MALT lymphoma than with gastric cancer, we decided to determine the gastrin and its receptors' mRNA expression and gastrin content in this tumour as well as the release of this hormone both into plasma and gastric lumen. Twenty MALT lymphoma patients were compared with 100 age- and gender-matched controls with similar dyspeptic symptoms.

RESULTS

The overall H. pylori seropositivity in MALT lymphoma was about 90% and CagA positivity was 70%, compared to 56% and 33%, respectively, in controls. The serum gastrin in MALT lymphoma was about sixfold higher than in controls while gastric luminal gastrin in these patients was over 70 times higher than in controls. Gastrin content in tumour was about 10-fold higher than in antral mucosa. Gastrin and gastrin-receptor (CCKB-receptor) mRNA were detected by reverse transcriptase-polymerase chain reaction in cancer tissue whilst in the fundic and antral mucosa, only enhanced expression of CCKB-receptor mRNA and gastrin mRNA was detected, respectively. Histamine stimulation in MALT lymphoma induced acid secretion that was only about 30% of control value due to atrophic gastritis. This study confirms an important role of CagA-positive H. pylori in the pathogenesis of MALT lymphoma and shows that this lymphoma is capable of synthesizing and releasing potent growth promoting gastrin, possibly due to the action on G-cells of H. pylori-originated Nalpha-methyl histamine and cytokines (tumour necrosis factor alpha and interleukin-8).

CONCLUSIONS

Gastric MALT lymphoma is closely linked to CagA-positive H. pylori infection. Gastrin and its receptors may be implicated in the pathogenesis of gastric lymphoma.

Nucleotide-induced movements in the myosin head near the converter region

Structural changes in subfragment 1 of skeletal muscle myosin were investigated by cross-linking trypsin-cleaved S1 with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. In the absence of nucleotide the alkali light chains are cross-linked to the 27 kDa heavy chain fragment; the presence of MgATP reduces the efficiency of this reaction. On the other hand, MgATP promotes the cross-link formation between the N-terminal 27 kDa and C-terminal 20 kDa fragments of the heavy chain. The chemical cleavage of the cross-linked heavy chains fragments with N-chlorosuccinimide and hydroxylamine indicates that the cross-links are formed between the regions spanning residues 131-204 and 699-809. These results indicate that the two regions of the heavy chain that are relatively distant in nucleotide-free skeletal S1 [Rayment et al. (1993) Science 261, 50-58] can potentially interact upon addition of nucleotide.

Adherence of bile-isolated bacteria to the bile ducts mucosa as a pathogenic factor in the development of inflammatory lesions

Bacterial infection of the bile system appears to be an important factor in the formation of stones. In view of the hypothesis that strains of E. c. form an essential factor in infections of the bile ducts, an attempt has been made to determine the connection between infections of the bile ducts and the adherence of E. c. to the epithelium of the gallbladder. The research covered 148 patients operated electively for cholecystolithiasis (121), cholecystocholedocholithiasis (26) and recurrent lithiasis (1). In bile collected from the gallbladder in the course of the operation, E. coli strains were isolated. Cholangioscopy performed in 26 patients enabled the macroscopic evaluation and grading of inflammatory lesions of bile duct mucosa. The mucosa of the gallbladder was evaluated histologically. The adherence test was performed using homologous and heterologous strains of E. c. isolated from the bile of gallstone patients. The adherence occurred most frequently in the neck of the gallbladder (71-100%) in those patients in whom an infectious process of the bile ducts mucosa was endoscopically diagnosed. The adherence of bacteria to the epithelium of the gallbladder did not depend on the type of inflammation (acute, chronic).

Protective role of endogenous nitric oxide (NO) in lipopolysaccharide--induced pancreatic damage (a new experimental model of acute pancreatitis)

Lipopolysaccharide (LPS) derived from the bacterial cell wall activates the inflammatory response in the tissue but the role of LPS in the pathogenesis of pancreatic damage and in the activation of NO system in the pancreas has not been fully explained. The aim of this study was to investigate the effect of repeated administration of LPS to the rats on the integrity of the pancreas, on the ability of isolated pancreatic acini to secrete the amylase and on the plasma level of tumor necrosis factor alpha (TNFalpha). The role of NO in the pancreatic resistance to the damage was assessed in animals subjected to repeated administration of LPS. To induce pancreatic damage one group of rats received intraperitoneal (i.p.) injection of LPS (from E. coli) every day during 5 consecutive days (10 mg/kg--day). Another groups of animals were given N(G)-nitro-L-arginine (L-NNA), an inhibitor of NO synthase (NOS) (20 mg/kg i.p.) alone or in combination with L-arginine (100 mg/kg i.p.), 30 min prior to each LPS injection. Plasma level of TNFalpha was determined by ELISA kit. Repeated administration of LPS produced mild pancreatic inflammation that was most pronounced at day 5 of LPS treatment and manifested as edema, neutrophil infiltration and hemorrhage of the pancreas. The survival rate after 5 days treatment with LPS was 87.5%. Pancreatic weight, plasma levels of TNFalpha and amylase, pancreatic blood flow (PBF) and NO generation by pancreatic acini were markedly increased in rats subjected to repeated administration of LPS whereas the amylase response of isolated pancreatic acini to pancreatic secretagogues was significantly attenuated. Suppression of NOS by L-NNA resulted in a dramatic increase in the mortality of the animals reaching 50% and significantly increased inflammatory changes in the pancreatic tissue, decreased PBF, abolished the ability of pancreatic acini to release NO and to secrete amylase. Pancreatic weight and plasma levels of amylase and TNFalpha significantly increased in the group of rats treated with combination of LPS+L-NNA as compared to the animals received LPS alone. Addition of L-arginine to L-NNA+LPS administration reversed all harmful effects produced by L-NNA in the pancreas. We conclude that repeated administration of high doses of bacterial LPS to the rats could induce pancreatic tissue damage by itself, however, it is not able to produce severe pancreatitis. Suppression of NO generation significantly aggravates the pancreatic lesion produced by LPS leading to the dramatic mortality in treated rats. The rise of plasma level of TNFalpha corresponds to the severity of pancreatic inflammation.

Helicobacter pylori and its eradication in rosacea

Rosacea is a common condition of unknown etiology usually accompanied by gastrointestinal symptoms and favorably responding to the treatment with antibiotics. This study was designed to examine the prevalence of gastric Helicobacter pylori (Hp) infection verified by 13C-UTB-test, CLO, Hp culture and serology (IgG) in patients with rosacea. Gastroduodenoscopy was combined with pentagastrin secretory test and antral and fundic biopsy samples were taken for histological evaluation (the Sydney system). Blood samples were also taken for the determination of plasma gastrin using RIA and plasma interleukin (IL)-8 and tumor necrosis factor alpha (TNFalpha) using ELISA. This study was performed in 60 patients, 31-72 year old, with visible papules and pustules associated with erythema and flushing on the face and on 60 age- and gender-matched patients without any skin diseases but with similar as in rosacea gastrointestinal symptoms but without endoscopic changes in gastroduodenal mucosa (non-ulcer dyspepsia - NUD). The Hp prevalence in rosacea patients was about 88 % as compared to 65% in control NUD patients. Among rosacea patients, 67% were cytotoxin associated gene A (CagA) positive, while in NUD patients only 32% were CagA positive. Rosacea patients showed gastritis with activity of about 2.1 in antrum and 0.9 in the corpus of the stomach while those with NUD only mild gastritis with activity of approximately 1.0) confined to the antrum only. Following initial examination, typical 1 wk anti-Hp therapy including omeprazole (20 mg bd.), clarithromycin (500 mg bd.) and metronidazol (500 mg bd.) was carried out. After eradication, 51 out of 53 treated rosacea patients became Hp negative. Within 2-4 weeks, the symptoms of rosacea disappeared in 51 patients, markedly declined in 1 and remained unchanged in 1 other subject. A dramatic reduction in activity of gastritis (to 0.3 in antrum and to 0.1 in corpus) was observed. Basal plasma gastrin decreased from 48 +/- 5 pM before to 17+/-3 pM after eradication, while pentagastrin-induced maximal (MAO) declined, respectively, from about 16.6 +/- 4.2 to 8.5 +/- 1.8 mmol/h. Plasma TNFalpha and IL-8 were reduced after the therapy by 72% and 65%, respectively. We conclude that: 1) Rosacea is a disorder with various gastrointestinal symptoms closely related to gastritis, especially involving the antrum mucosa, with Hp expressing cagA in the majority of cases and elevated plasma levels of TNFalpha and IL-8; 2) The eradication of Hp leads to a dramatic improvement of symptoms of rosacea and reduction in related gastrointestinal symptoms, gastritis, hypergastrinemia and gastric acid secretion; and 3) Rosacea could be considered as one of the major extragastric symptoms of Hp infection probably mediated by Hp-related cytotoxins and cytokines.

Association of Helicobacter pylori infection with coronary heart disease

The role of Helicobacter pylori (HP) as the main etiological factor in gastritis and peptic ulcer disease is undisputable. Gastric mucosal damage caused by HP involves various bacterial and host-dependent toxic substances that have been recently associated with an increased risk of coronary artery disease (CAD), possibly through the activation acute phase response and of procoagulant hemostatic factors. Recent studies showed a close and strong correlation between plasma increments of some cytokines such as IL-6 or TNFalpha and cardiovascular diseases. HP infection induces platelet activation and aggregation that could be the pathogenic explanation of the association between HP infection and CAD. The aim of this study was to determine the seroprevalence of HP infection and antibodies to CagA, an antigen that is expressed by the most virulent HP strains inducing an enhanced gastric inflammatory response, in patients undergoing routine coronary artery examination. We studied 76 patients with CAD and 81 healthy controls patients without significant change in coronary circulation. Angiograms were read by two independent experienced cardiologists blinded to the results of HP status. The presence of serum IgG antibodies to HP and to CagA and plasma interleukin-8 (IL-8) levels was measured by ELISA. In addition plasma C-reactive protein fibrinogen, total cholesterol and lipids levels were measured in all studied patients. Seropositivity to HP was found in 81.5 % of cases and in 51% of controls and the difference in prevalence was statistically significant, the odds ratio being 4.3 for Hp patients. Antibody to CagA protein was detected in 47.3% of CAD but only in 28% of healthy controls (OR = 2.3 vs OR = 10). C-reactive protein, plasma fibrinogen and total cholesterol were, respectively higher in patients with CAD than in controls. Present data show that there is significant link between CAD and HP infection. The HP infection significantly increases the risk of CAD, especially when both the anti-HP IgG and anti-CagA IgG are considered. Higher prevalence of cytotoxic HP strains might enhance the atherosclerotic process by inducing a persistent, low grade inflammatory response in arterial wall with enhanced synthesis of acute phase reactants.

Role of gastrin in gastric cancerogenesis in Helicobacter pylori infected humans

Numerous epidemiological studies demonstrated the association between Helicobacter pylori (H. pylori) infection and gastric cancer but the mechanism of the involvement of H. pylori in gastric cancerogenesis remains virtually unknown. This study was designed to determine the seropositivity of H. pylori and cytotoxin associated gene A (CagA), serum gastrin and gastric lumen gastrin levels under basal conditions and following stimulation with histamine in gastric cancer patients and controls. 100 gastric cancer patients aging from 21 to 60 years and 300 gender- and age-adjusted controls hospitalized with non-ulcer dyspepsia (NUD) entered this study. 13C-Urea Breath Test (UBT), serum immunoglobulin (IgG) antibodies to H. pylori and CagA were used to assess the H. pylori infection and serum levels of IL-1beta, IL-8 and TNFalpha were measured by enzyme-linked immunosorbent assay (ELISA) to evaluate the degree of gastric inflammation by H. pylori . Gastrin-17 mRNA and gastrin receptors (CCK(B)) mRNA expression in gastric mucosal samples taken by biopsy from the macroscopically intact fundic and antral mucosa as well as from the gastric tumor was determined using RT-PCR. The overall H. pylori seropositivity in gastric cancer patients at age 21-60 years was about 92%, compared, respectively, to 68%, in controls. A summary odds ratio (OR) for gastric cancer in H. pylori infected patients was about 5.0 . The H. pylori CagA seropositivity in gastric cancer patients was about 58.5% compared to 32.4% in controls, giving the summary OR for gastric cancer in CagA positive patients about 8.0. The prevalence of H. pylori- and H. pylori CagA-seropositivity was significantly higher in cancers than in controls, irrespective of the histology of gastric tumor (intestinal, diffuse or mixed type). Median IL-1beta and IL-8 reached significantly higher values in gastric cancer patients (9.31 and 30.8 pg/ml) than in controls (0.21 and 3.12, respectively). In contrast, median serum gastrin in cancers (as total group) was several folds higher (62.6 pM) than in controls (19.3 pM). Also median luminal gastrin concentration in gastric cancer patients was many folds higher (310 pM) than in controls (20 pM). This study shows for the first time that cancer patients are capable of releasing large amounts of gastrin into the gastric lumen to increase luminal hormone concentration to the level that was recently reported to stimulate the growth of H. pylori. There was no any correlation between plasma gastrin levels and gastric luminal concentration of gastrin suggesting that: 1) luminal gastrin originates from different source than plasma hormone, most probably from the cancer cells, 2) cancer cells are capable of expressing gastrin and releasing it mainly into the gastric juice and 3) the gastric cancer cells are equipped with gastrin-specific (CCK(B)) receptor so they exhibit the self-growth promoting activity in autocrine fashion. This notion is supported by direct detection of gastrin mRNA and gastrin receptor (CCK(B)-receptors) mRNA using RT-PCR in cancer tissue. To our knowledge this is the first study showing an important role of gastrin as self-stimulant of cancer cells in patients infected with H. pylori. Basal and histamine maximally stimulated acid outputs were significantly lower in gastric cancer patients than in controls despite of enhanced gastrin release, particularly in cancer patients and this might reflect the mucosal inflammatory changes (increased serum levels of proinflammtory interleukins - IL-1beta and IL-8), that are known to increase gastrin release. We conclude that: 1) H. pylori infected patients, particularly those showing CagA-seropositivity, are at greatly increased risk of development of gastric cancer, 2) H. pylori-infected cancer patients produce significantly more IL-1beta and IL-8 that might reflect an H. (ABSTRACT TRUNCATED)

Mouse model of Helicobacter pylori infection: studies of gastric function and ulcer healing

BACKGROUND

Helicobacter pylori infection in humans is a major risk factor for peptic ulcer, but studies on the relation between H. pylori infection and gastric pathology are limited due to a deficiency of convenient animal models resembling this infection in humans.

METHODS

We studied the effects of inoculation of conventional BALB/c mice with CagA and VacA positive (type I) H. pylori or CagA and VacA negative H. pylori (type II) strains on gastric secretion and healing of chronic acetic acid-induced ulcers in mouse stomachs. The ulcer area, gastric blood flow, plasma interleukin (IL)-1beta and IL-12, as well as plasma gastrin and gastric luminal somatostatin were determined. Gastric mucosal biopsy samples were also taken for assessment of the presence of viable H. pylori using a rapid urease test, H. pylori-culture and the RT-PCR analysis of the signal for H. pylori CagA.

RESULTS

Gastric acid and pepsin secretion was reduced by over 50% immediately after H. pylori inoculation and accompanied by a significant increment in plasma gastrin and fall in gastric luminal somatostatin content observed over all test days, particularly in mice infected with type I H. pylori. The area of ulcers in vehicle-treated controls decreased significantly starting from day 2 after ulcer induction and then continued to decline for a further 14 days to heal almost completely after 28 days. In contrast, the ulcers were present until day 28 in all mice infected with type I or type II H. pylori strains, being significantly larger, especially with type I H. pylori infection. The gastric blood flow at the ulcer margin and ulcer crater in vehicle-treated mice gradually increased with decreasing ulcer size, after 14 and 28 days reaching a value which was not significantly different from that in vehicle-administered mice. In contrast, the gastric blood flow in type I H. pylori and, to a lesser extent, in type II H. pylori infected mice was significantly lower than in vehicle controls, both at the margin and at the crater of ulcers at all tested days. Histological changes such as oedema or congestion of surface epithelium were found after 7 days whereas mucosal inflammatory infiltration appeared after 14 days with a further increase after 28 days, especially in type I H. pylori and to a lesser extent in type II H. pylori infected mice. Plasma IL-1beta and IL-12 were significantly elevated at all tested days of ulcer healing and their increments were significantly higher in type I than in type II H. pylori infection.

CONCLUSIONS

Conventional mice with gastric ulcers can be successfully infected by both toxigenic and nontoxigenic H. pylori strains, and this infection causes an immediate suppression of gastric secretion and markedly delays the healing of ulcers due to the fall in mucosal microcirculation in the ulcer region, cytokine release and an impairment in the gastrin-somatostatin link that appears to be independent of gastritis and more pronounced with infection of toxigenic than nontoxigenic strains.

Water extracts of Helicobacter pylori delay healing of chronic gastric ulcers in rats: role of cytokines and gastrin-somatostatin link

BACKGROUND

Helicobacter pylori (Hp) is considered as a major risk factor of peptic ulcer, but the pathogenic mechanism of its action has not been fully explained.

AIMS

This study was designed: (1) to compare the ulcer healing effects of water extract (WE) obtained from type-I cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA) expressing Hp and from type-II CagA- and VacA-negative Hp strain with those of vehicle (saline), and (2) to determine the alterations in gastric secretion, gastric blood flow (GBF) and expression of Hp-related cytokines during the ulcer healing in rats treated with toxigenic (type-I) and non-toxigenic (type-II) Hp-derived WE.

METHODS

Gastric ulcers were produced by serosal application of acetic acid in rats with or without gastric fistula treated with vehicle (saline) or WE originating from type-I or type-II Hp administered intragastrically on days 1, 3, 5 and 7 upon ulcer induction. On days 3, 9 and 15, animals were lightly anesthetized with ether, the abdomen was opened and the GBF was measured by the H2-gas clearance technique in the ulcer area and non-ulcerated mucosa. Venous blood was withdrawn for the measurement of plasma cytokine (IL-1beta and TNFalpha) levels and plasma and gastric contents were also collected for gastrin and somatostatin determination by specific radioimmunoassay.

RESULTS

Gastric ulcers healed gradually in vehicle-treated controls and the ulcer area on days 3, 9 and 15 was reduced by 12, 43 and 92%, respectively. In rats treated with WE of type-I Hp, ulcer healing was significantly delayed, and gastritis and infiltration of ulcerated gastric mucosa with inflammatory cells were observed histologically. The prolongation of ulcer healing by WE of both Hp strains was accompanied by a marked fall in the GBF at the ulcer margin and transient hyposecretion especially in rats given WE of type-I Hp strain. On day 15 of ulcer healing, the plasma concentration of IL-1beta and TNFalpha was negligible in vehicle control rats, but it was significantly elevated particularly in rats treated with WE of type-I Hp. RT-PCR analysis revealed that mucosal expression of IL-1beta and TNFalpha mRNA was significantly upregulated in the gastric mucosa of rats treated with either toxigenic or non-toxigenic Hp WE. The plasma gastrin level was significantly higher and the luminal concentration of somatostatin was significantly lower in rats treated with Hp-WE than in vehicle-treated controls and these alterations were more pronounced in rats treated with WE type-I than type-II Hp.

CONCLUSIONS

WE of toxigenic Hp strain delays ulcer healing due to the reduction in the gastric microcirculation at the ulcer margin, the overexpression of inflammatory cytokines and the impairment of the gastrin-somatostatin link.

Gastric secretion and ulcer healing in mouse stomach infected with cytotoxin expressing strain of Helicobacter pylori

Helicobacter pylori (Hp) is a major risk factor of peptic ulcer but studies on the relation between Hp infection and gastric pathology are limited due to lack of convenient models resembling Hp infection in humans. We studied the effects of inoculation of conventional BALB/c mice with toxigenic type I Hp (cagA+ and vacA+) and non-toxigenic type II Hp (cagA- and vacA-) vs administration of vehicle on gastric secretion and healing of gastric ulcers. The gastric secretion studies were performed on mice with chronic gastric fistula before and after inoculation with toxigenic or non-toxigenic Hp strain or administration of vehicle (saline). Gastric ulcers were produced in mice inoculated with toxigenic and non-toxigenic Hp strain or vehicle and then sacrificed at day 0 and after 2, 4, 7, 14 and 28 days. Ulcer area and gastric blood flow (GBF), plasma gastrin and gastric luminal somatostatin were determined. Gastric mucosal biopsy specimens were also taken for the assessment of the presence of viable Hp using rapid urease test, the Hp-culture and the reverse transcriptase--polymerase chain reaction (RT-PCR) analysis of the signal for Hp CagA. Gastric acid output was reduced by over 50% immediately after Hp inoculation and this effect persisted during all time intervals tested, being significantly more pronounced in type I Hp-infected stomach. The area (7 mm2) of ulcers in control mice decreased gradually and then continued to decline during 14 days to disappear almost completely after 28 days. In contrast, the ulcers were present till day 28 in all mice infected with type I or type II Hp strain being significantly larger especially with type I Hp-infection. The GBF in control mice showed gradual rise with decreasing ulcer size being significantly higher at the ulcer margin than the ulcer crater and reached after 14 and 28 days the value not significantly different from that in vehicle-administered mice. In contrast, the GBF in type I Hp-infected mice but to a lesser extent, in type II Hp infected mice was significantly lower than in the vehicle controls, both at the ulcer margin and the crater of ulcers at all tested days. Hp-infection was accompanied by significant increment in plasma gastrin and the fall in gastric somatostatin contents observed at all test days, particularly in mice infected with type I Hp strain. Edema of surface epithelium appeared after 7 days and wak but significant mucosal inflammatory infiltration occurred after 14 days to further increase after 28 days, especially in type I Hp and less in type II Hp infected mice. We conclude that conventional mice with gastric ulcers can be successfully infected by both toxigenic and non-toxigenic Hp strains and this infection markedly reduces gastric acid secretion and delays healing of ulcers probably due to the fall in mucosal microcirculation in ulcer area, mucosal inflammation and impairment in gastric-somatostatin link.

[Results of prophylactic and curative antibiotic therapy in biliary surgery]

Prophylactic antibiotic regimen (gentamicin, clindamycin) was assessed in a group of 104 patients operated electively on biliary lithiasis (cholecysto- and choledocholithiasis). Antibiotic prophylaxis was performed in group of 20 patients, in 6 of them antibiotics were continued postoperatively. Intraoperatively antibiotics were given in a group of 20 patients--curative treatment. Control group consisted of 58 patients. We concluded that "one shoot" antibiotic therapy is valuable in controlling of wound infections. But the most effective method of reducing local septic complications rate combines prophylaxis with prolonged antibiotic administration.

Oral cavity as permanent reservoir of Helicobacter pylori and potential source of reinfection

Recent studies in developed countries showed that neither dental plaques nor dentures are important reservoir for Helicobacter pylori (Hp), whereas studies in developing countries revealed a high prevalence of Hp in dental plaques, though elsewhere the culture of bacterium or its DNA analysis by polymerase chain reaction in the material obtained from oral cavity were not successful. This study was designed to compare the incidence of Hp in oral cavity (saliva, dental plaques and gingival pockets) using Campylobacter-like organism (CLO) test and culture and in the presence of Hp in the stomach using 14C-urea breath test (UBT), CLO-test and culture (antral biopsy specimens). Hundred dyspeptic subjects with endoscopically normal gastro-duodenal mucosa and 55 symptomatic patients with active duodenal peptic ulcer (DU) were tested for the presence of Hp. Thirty of these DU patients were also examined for presence of Hp in oral cavity and the stomach just before the start and 4 weeks after the termination of one week triple therapy (Omeprazole 20 mg bd, Clarithromycin 500 mg bd and Tinidazole 500 mg bd) when the DU was found endoscopically healed. In the group of 100 dyspeptic subjects, the Hp was detected by CLO-test in saliva, dental plaques and gingival pockets in 84%, 100% and 100% of cases and by the culture in 55%, 88% and 100%, respectively. The presence of Hp, as determined by UBT in the stomach in these subjects was 60%. Using CLO-test and culture, all (100%) out of 55 DU patients, were found to be Hp positive in the oral cavity and in 95% in the stomach. Following one week triple therapy in 30 DU patients, the Hp was still detected in oral cavity by CLO-test in all patients (100%) and by culture in 27 patients (90%), whereas in the stomach, the Hp was found by UTB and culture only in one of these patients (97% Hp eradicated). We conclude that the Polish population including dyspeptic and DU patients, the mouth is permanent reservoir of Hp and that the successful Hp eradication from the stomach by systemic therapy fails the Hp status in the oral cavity that might be a potential source of gastric reinfection in these patients.

Immunoblot analysis of immune response to cell surface antigens of different Helicobacter pylori strains

Infection with H. pylori has been strongly associated with chronic type B gastritis and peptic ulcer disease, although pathogenic mechanisms of H. pylori infection are still unclear. We examined the structure and antigenicity of water extract of 5 H. pylori strains and immunoblotting with homologous immune rabbit serum. All the tested rabbit sera recognized the protein component between 31-66 kD. The 31-66 kD protein bands are highly specific for H. pylori. Only strain isolated from patients with gastric or duodenal ulcer disease gave visible bands with the major proteins 98, 116 kD.

Bacteria in bile of patients with bile duct inflammation

Bile samples taken intraoperatively from 100 patients with three different bile system diseases were subjected to bacteriological analysis. Statistically significant differences between the types of aerobic and anaerobic bacteria present in the bile were found.

[Gasometric studies and lactic acid determinations in arterial blood and cerebrospinal fluid in brain infarction]

In 54 cases of brain infarction and 17 control cases the gasometric parameters and lactic acid level were determined in arterial blood and cerebrospinal fluid. Metabolic acidosis was demonstrated in the arterial blood and cerebrospinal fluid. Respiratory acidosis compensated partly metabolic acidosis. Changes in the cerebrospinal fluid were more frequent and more pronounced, especially in cases with fatal outcome. Deep disturbances of acid-base balance complicated with hypoxia may have prosnostic significance while moderate rise in lactic acid level is without this significance.

[Statistical correlation between lactate concentration and acid-base equilibrium in cases of brain tumors, craniocerebral injuries and meningitis]

Statistical significance of correlations between lactate concentration and pH value as well as pCO2 in the cerebrospinal fluid was assessed in patients with brain tumours, craniocerebral injury and meningitis. After calculation of correlation indices it was found that with increasing lactate level the correlation between this level and the pH and pCO2 of the cerebrospinal fluid increases. Correlation coefficients were far from their maximal values (+1 or -1) which indicates absence of a direct cause-and-effect relationship between lactate concentration and both remaining values. The analysis of results in the group with lactate level exceeding 30 mg/100 ml demonstrated lowest correlation coefficients between these values in patients with meningoencephalitis.