Helicobacter heilmannii gastritis: a histological and immunohistochemical trait.

AIM: Biopsies of the gastric antrum were reviewed over a period of 10 years to determine the prevalence of Helicobacter heilmannii in symptomatic subjects from this geographical area and to relate its presence to distinctive histopathological and immunohistochemical features. METHODS: Biopsies from 7926 symptomatic patients were reviewed. Ten serial sections were stained with haematoxylin and eosin for conventional histology. Another 10 sections were stained with the Gram method for spiral bacteria. When H heilmannii was suspected, 10 additional serial sections were stained with methylene blue to obtain homogeneous colouring. An equal number of sections from patients affected by isolated H heilmannii or H pylori gastritis were analysed by immunohistochemistry to evaluate lymphoid aggregate/mucosal lymphocyte clonality (CD20 and CD3) and tumour necrosis factor alpha (TNF-alpha) in stromal cells. RESULTS: The prevalence of H heilmannii was 0.1% (eight of 7926), whereas H pylori was present in 60.7% of patients (4813 of 7926). In two of the eight H heilmannii positive patients both helicobacters were found. In all subjects infected by H heilmannii only, distinctive histology (lymphocyte exudation into gastric foveolae) was seen. Lymphoid aggregates, chronic mucosal inflammation with patchy activity, and the absence of epithelial mucus depletion were regular features of H heilmannii gastritis. Immunohistochemistry did not reveal different lymphocyte clonal patterns between H pylori and H heilmannii gastritis: CD20 positive cells were predominant in the centre of aggregates and mucosal infiltrates, whereas CD3 positive cells were prevalent at the periphery of follicles. Only H pylori gastritis showed a significant increase in TNF-alpha positive stromal cells. CONCLUSION: These data suggest that an unusual lymphocyte reaction, with the tendency to invade the foveolar lumen, is a distinctive histopathological aspect of H heilmannii chronic gastritis, although further studies in a larger series are necessary to confirm this fact. Nevertheless, lymphocyte clones do not differ qualitatively from those found in H pylori infection. Moreover, compared with H heilmannii, H pylori provokes a more intense release of TNF-alpha, suggesting that different inflammatory responses exist to these two organisms.

Halitosis and Helicobacter pylori: a possible relationship.

With the aim of investigating a possible relationship between "objective" halitosis (established by sulfide levels in the breath) and Helicobacter pylori, we performed a study in 58 dyspeptic patients reported to suffer from "bad breath." Furthermore, we evaluated the effects on halitosis of eradication therapy (only for H. pylori-positive patients) and chlorhexidine antiseptic mouth rinses (in all patients). Sulfide compound assay indicated objective halitosis in 52/58 patients, 30 of whom were positive and 22 negative for H. pylori. In 19/30 eradication by double therapy provoked a decrease to below the cutoff value of sulfide levels in 15. In the other 11 of the 30 subjects, in whom H. pylori positivity persisted, halitosis parameters did not change. Chlorexidine reduced sulfides to below the cutoff value in 16/22 H. pylori-negative patients, but did not provoke any change in the 11 unsuccessfully treated H. pylori-positive subjects. In these, objective halitosis disappeared only after a successful eradication by triple therapy (9/11). Our results show a possible association between halitosis and H. pylori since bacterial eradication may resolve the symptom. Antiseptic mouthwashes may be effective only in absence of H. pylori, when halitosis may be due to oral putrefactive microbial activity. In a small number of subjects the cause and treatment of halitosis need to be clarified.

Effect of Helicobacter pylori eradication on gastric epithelial proliferation. Relationship with ras oncogene p21 expression.

BACKGROUND: Impaired changes in gastric epithelium proliferation have been described in Helicobacter pylori infection, and a progressive increase of proliferating cells has been shown with the progression of mucosal lesions. AIMS: Purpose of this investigation was to study the effect of eradication on bacterium-induced proliferative changes, evaluated by the proliferating cell nuclear antigen labelling index (PCNA LI) and its relationship to the ras oncoprotein p21, involved in early events of gastric carcinogenesis. PATIENTS AND METHODS: This retrospective study was performed, before and after therapy, in five different groups of patients with progressive stages of Helicobacter pylori damage (N: normality; HG: histological gastritis with normal endoscopy; EHG: histological gastritis with endoscopic chronic erosions; CIM: complete intestinal metaplasia; IIM: incomplete intestinal metaplasia). RESULTS: Six months after eradication, a normalization of PCNA LI was observed in the areas of gastritis, but not in those of intestinal metaplasia, which showed on unchanged type. Moreover, immunohistochemical membrane expression of ras oncoprotein p21 was only associated to intestinal metaplasia. The protein was also expressed in the cytoplasm in 3 patients with incomplete type. CONCLUSIONS: These results suggest that the development of intestinal metaplasia may be associated with an alteration in the control of gastric epithelium proliferation and could represent an initial stage in gastric carcinogenesis. Nevertheless, further genetic changes are necessary for a complete progression to neoplastic disease. A long-term follow-up on extension, type, proliferative situation and oncoprotein expression in areas of intestinal metaplasia may be helpful to explain whether the present data provide new information on the mechanism of Helicobacter pylori induced gastric carcinogenesis.

Different priming on human neutrophil respiratory burst by lipopolysaccharides from phase I and phase II Coxiella burnetii.

Human neutrophils produce small amounts of superoxide anion when stimulated with the chemotactic peptide FMLP; preincubating neutrophils with low concentrations of lipopolysaccharides (LPS) markedly increases this response, an effect referred to as priming. In this work LPS from Coxiella burnetii either phase I (virulent) or phase II (avirulent) were examined for their ability to induce priming. Results clearly show that only LPS from phase II microorganism was able to increase the release from neutrophils upon subsequent stimulation with FMLP. This effect was abolished by preincubation of LPS with polymyxin B. This finding may account for the ability of Coxiella burnetii phase I to escape intracellular phagocyte killing during persistent infections.

Induction of procoagulant activity in human leukocytes with lipoglycans from mycoplasmas.

Lipoglycans from mycoplasmas possess the ability to induce the elaboration of procoagulant activity. This represents a third endotoxic property for these polymers, in addition to the pyrogenicity and clotting of Limulus lysate reported previously. Lipoglycans from three species of Acholeplasma (A. axanthum, A. granularum, and A. oculi) stimulated the elaboration in vitro of procoagulant activity by human mononuclear cells to differing extents. Two serotypes, 3 and 4, of Ureaplasma urealyticum also exhibited this stimulatory activity. The activities of lipoglycans tested were, in decreasing order, A. oculi greater than U. urealyticum type 4 greater than A. axanthum greater than U. urealyticum type 3 greater than A. granularum.

Relationship between immune system and gram-negative bacteria, binding of Salmonella pullorum-gallinarum to chicken lymphocytes.

Salmonella pullorum-gallinarum binding to chicken lymphocytes has been evaluated in individuals of different age (1-20 wks). Bacterial adherence has been studied on lymphoid cells recovered from thymus, spleen, bursa and peripheral blood. Binding was age-dependent and neuraminidase treatment of lymphoid cells led to an increase of adherence. In addition, by using two monoclonal antibodies, the CT-1, which defines thymocytes and the M-4 which identifies surface IgM and an avian homologue of mammalian IgD on B lymphocytes, distribution of Salmonella pullorum-gallinarum binding to T and B lymphocytes has been analyzed. Results show that either T lymphocytes or B lymphocytes have the capacity to form rosettes with Salmonella. In particular, B cells from bursa and spleen display the highest capacity of adherence to bacteria, this supporting the defence function which has been attributed to bursa of Fabricius.

[Induction of thromboplastin-like procoagulating activity by Mycoplasma pneumonia]. / Induzione di attivita' procoagulante tromboplastino-simile da parte di Mycoplasma pneumoniae.

The capacity of a strain of Mycoplasma pneumoniae to induce the production of procoagulant activity by human mononuclear cells is described. This finding could contribute to the understanding of the pathogenetic mechanism(s) involved in the thromboembolic complications often associated with fatal cases of Mycoplasma pneumoniae infection.

[Generation of pro-coagulation activity by leukocytes stimulated in vitro with lipoglycans from mycoplasmas]. / Generazione di attività procoagulante da parte di leucociti stimolati in vitro con lipoglicani di micoplasmi.

Lipoglycans represent a special type of lipopoly-saccharide that differs in structure from the well-known gram-negative bacteria lipopolysaccharide. After briefly describing their most important characteristics, the authors take into consideration the in vitro interaction between lipoglycans from Acholeplasma granularum, Acholeplasma oculi, and Acholeplasma axanthum and human leukocytes in terms of production of procoagulant activity. The results obtained show that the examined lipoglycans possess, similarly to lipopolysaccharides, the capacity to induce the production of procoagulant activity, thromboplastin-like, from human mononuclear cells. However, the pathophysiological significance of this endotoxin-like activity remains to be established.

Leukocyte inhibiting factor (LIF) production from human lymphocytes stimulated by bacterial lipopolysaccharides.

Leukocyte inhibiting factor (LIF) release from lymphocytes cultures stimulated by bacterial lipopolysaccharides (LPS) has been investigated. Human lymphocytes cultured in the presence of E, coli or S. enteritidis LPS were able to release in the supernatants a substance with the following properties: a) same elution pattern of Bovine Serum Albumin (MW 69000) when filtered on Sephadex G-100; b) it migrates on disc electrophoresis a an albumin; c) not dialyzable; d) not cytotoxic; e) inhibition of polymorphonuclear cells migration in agarose plates; f) heat stability at 56 degrees C for 30'. This substance could be likely identified as LIF.