Direct activity of recombinant human lactoferrin against Helicobacter pylori

We report the activity of recombinant human lactoferrin against Helicobacter pylori. Lactoferrin exerted a time- and dose-dependent action against 8 of the 13 clinical isolates of H. pylori tested in vitro. These results highlight a potential therapeutic use for lactoferrin against H.pylori infection.     

Iron acquisition by Helicobacter pylori: importance of human lactoferrin

Helicobacter pylori is known to be an etiologic agent of gastritis and peptic ulcer disease in humans. However, the mechanism by which this organism acquires iron has not been studied. For this investigation, H. pylori was grown in iron-restricted medium. Siderophore production was not detected by chemical assays, and the strains were unable to use enterochelin and pyochelin for growth in low-iron media. Human lactoferrin supported full growth of the bacteria in media lacking other iron sources, but neither human transferrin, bovine lactoferrin, nor hen ovotransferrin served as a source for iron. Since lactoferrin was found in significant amounts in human stomach resections with superficial or atrophic gastritis, the iron acquisition system of H. pylori by the human lactoferrin receptor system may play a major role in the virulence of H. pylori infection.     

Antibiotic resistance in Helicobacter pylori: implications for therapy

In most previous reports telomerase activity in lung cancer patients has been detected using tissue extracts. We have developed a semiquantitative fluorescence-based TRAP assay using fluorescence-end-labeling primers. Moreover, we also developed an in situ TRAP assay that detects telomerase activity at the cellular level. Thus, using these TRAP assays, we can detect telomerase activity in lung cancer cells obtained from bronchial washings. A high incidence of lung cancer patients with class I-III cytology had detectable telomerase activity, thus, a combination of a cell extract based. TRAP assay and an in situ TRAP assay may provide additive information to cytology for the diagnosis of lung cancer.     

Helicobacter pylori infection

CHROMagar, a chromogenic differential culture medium, is claimed to facilitate the isolation and presumptive identification of certain clinically important yeast species, e.g., Candida albicans. This study evaluated the cost-effectiveness and time advantage of using it in comparison with Sabouraud dextrose agar (SDA). Three possible pathways, each of which included the use of one or both media, were compared in a routine laboratory. A total of 21 yeast isolates was cultured from 298 clinical samples from neutropenic and AIDS patients. An overall sensitivity of 95.2% was observed for each medium and primary isolation on CHROMagar was found to be 100% sensitive and 100% specific for C. albicans. For identification purposes, after initial culture the use of CHROMagar provided the most economical and least time-consuming method. Direct inoculation on to CHROMagar is recommended for blood cultures when yeast cells are seen on microscopy and where early appropriate therapy is imperative.     

Infection with Helicobacter pylori

60 male Nigerian prison inmates (30 with convicted status and 30 awaiting trial) and 210 male noninmates were administered the Tennessee Self-concept Scale to test the hypotheses that (1) inmates with convicted status would obtain higher self-concept scores than those with ?awaiting trial? status, and (2) the self-concept scores of prison inmates generally would be lower than those of noninmates. The two hypotheses were strongly supported for this sample. It was concluded that self-concept scores were not only related to delinquency by also to custodial status.     

Helicobacter pylori in children

Helicobacter pylori is the major cause of antral gastritis in children, however, it is not always associated with symptoms. The exception to this occurs in duodenal ulcer disease with which H. pylori is linked in children albeit less strongly than in adults. Duodenal ulcers do not recur in older children following eradication of H. pylori. The importance of asymptomatic carriage of H. pylori in children, particularly in relation to the duration of this infection and the subsequent development of gastric cancer, remain to be established. Helicobacter pylori is associated with both hypochlorhydria and persistent diarrhoea in children in developing countries, but the significance of this association is still unknown. Although there is no consensus on the optimal regimen for treating H. pylori infection in children, dual therapy with amoxycillin and bismuth subcitrate for 2 weeks followed by monotherapy with bismuth subcitrate for a further 6 weeks will eradicate H. pylori infection in the majority of children. Those who relapse may be treated with a repeat course plus metronidazole for 4 weeks. Compliance with such regimens is a problem and shorter treatment courses that are equally effective in children need to be defined. Similarly, studies are required on the influence of the intrafamilial reservoir of H. pylori infection on relapse after treatment and the need for whole family eradication therapy.     

Helicobacter pylori in 1997

In this review Helicobacter pylori (H. pylori) infection and its relation to different diseases is presented. H. pylori doesn't cause inconvenience to most infected people, though all infected persons have chronic active gastritis. The 10 year risk of peptic ulcer for people infected with H. pylori is about 10%. Randomized double-blinded trials have shown that eradication of H. pylori can cure most patients with peptic ulcer disease. Some people infected with H. pylori develop atrophic gastritis which is a risk factor for development of gastric cancer. It is not known if H. pylori screening and eradication would have a prophylactic effect against gastric cancer. It is also unknown if persons with non-organic dyspepsia and persons in long-term treatment with proton-pump-inhibitors would benefit from H. pylori eradication.     

Virulence and colonization-associated properties of Helicobacter pylori isolated from children and adolescents

OBJECTIVE: We describe the sonographic appearance and vascularization of hemangiomas and determine if vessel density and peak systolic Doppler shifts distinguish hemangiomas from other superficial soft-tissue masses. SUBJECTS AND METHODS: Our pilot study included 20 infants and children with hemangiomas who were to undergo biopsy before treatment with interferon alpha-2b. We used Doppler sonography to determine the number of vessels per square centimeter, peak arterial Doppler shift, resistive index, and signs of arteriovenous shunting. All hemangiomas showed high vessel density (more than five per square centimeter) and high Doppler shifts (more than 2 kHz), and these two factors became our diagnostic criteria. A prospective study of 116 patients was then carried out. One hundred sixteen consecutive pediatric patients with superficial soft-tissue masses were examined using Doppler sonography; sonographic findings were compared with the final diagnoses that were established by biopsy, CT, or clinical follow-up. RESULTS: The final diagnoses included 70 hemangiomas, 20 venous malformations, three arteriovenous malformations, three arteriolocapillary malformations, and 20 other masses. Fifty-nine lesions showing high vessel density (more than five per square centimeter) and a peak arterial Doppler shift exceeding 2 kHz were correctly diagnosed as hemangiomas (sensitivity, 84%; specificity, 98%). One arteriovenous malformation showed high vessel density and high Doppler shifts, but none of the other masses that were not hemangiomas did. Eleven patients with hemangiomas who were being treated with interferon at the time of the study fulfilled only one of the two diagnostic criteria. CONCLUSION: High vessel density and high peak arterial Doppler shift can be used to distinguish hemangiomas from other soft-tissue masses.     

Treatment of Helicobacter pylori infection

The article presents information gained from a survey among Norwegian hospitals in March 1997 concerning their treatment of infections with Helicobacter pylori. Altogether 52 hospitals answered the questionnaire. A combination of proton pump inhibitors, metronidazole and clarithromycin was used by 59% as first choice and urea quick test (94%) and urea breath test (42%) as the primary diagnostic procedures, whereas serology was in little use (17%). Besides ordinary ulcer disease, indications for treatment were: ulcer induced by non-steroid anti-inflammatory drugs (79%), gastrooesophageal reflux (37%), non-ulcer dyspepsia (14%) and cancer prophylaxis (14%). The gastro group at the Department of Pharmacotherapeutics at the University of Oslo invited specialists from all health regions to discuss indications for treatment of H pylori, the diagnosis and the role of general practitioners. The extensive use of clarithromycin might be doubtful due to development of resistance. Indications for treatment of H pylori other than ulcer disease and mucosa associated lymphoid tissue lymphoma are still uncertain. Uncritical use of serological tests in primary care should be discouraged. At present there is no uniform strategy for the diagnosis and treatment of H pylori infection, and a coordinated strategy between general practitioners and specialists is needed.     

The microbiology of Helicobacter pylori

In this case the authors describe a patient with primary microinvasive adenocarcinoma of the eso-cervix, with the cervical canal not involved by the pathology, diagnosed by colposcopy followed by biopsy. Before the diagnosis of microinvasive adenocarcinoma the patient was scheduled for electrocautery of the suspicious area due to the fact that previous Pap-smears had always been negative. The authors underline the important role of colposcopy as a diagnostic tool that should be mandatory before any surgical therapy on the cervix and that allowed to diagnose such a rare cervical tumor.     

Treatment of Helicobacter pylori infection

Since acceptance of the association between Helicobacter pylori and peptic ulcer disease, eradication of H. pylori has become the standard of care in the treatment of peptic ulcer disease. Unfortunately, eradication therapy is no easy task, especially when one is faced with a myriad of drug combinations with varying degrees of efficacy and tolerability. The following is a review of the literature regarding the drugs and drug combinations used to eradicate H. pylori and their effectiveness both as single agents and in combination.     

Physiopathology of Helicobacter pylori infection

The gastric juice of Helicobacter pylori-infected individuals contains substantially higher levels of phospholipase A2 (PLA2) than that of individuals who are not infected. We present a new theory for how this H. pylori-induced PLA2 activity in gastric juice may play a major role in the development of peptic ulcer disease. When activated at neutral pH (pH 6.5-7.0), PLA2 may damage the surfactant-like, phospholipid-rich layer which constitutes an important part of the mucus barrier. Pepsin and other proteases, activated at low pH (pH 1.0-3.5), may then denature and cleave PLA2-exposed proteins. Peptic ulcers therefore tend to develop in regions exposed to changing luminal pH, such as the duodenal bulb when acid production is high or normal, or in the stomach when acid secretion is low.     

Pathogenic diversity of Helicobacter pylori

Helicobacter pylori has been shown to possess a very heterogeneous genoma despite its common phenotypic properties. Some characteristics relevant to pathogenesis have also been found to be heterogeneous. This is the case for adherence properties and the amount of urease produced, but it was not possible to relate these properties to disease entities. A vacuolating cytotoxin which alters epithelial cells has been found in about 60% of strains isolated from patients with ulcers versus 30% from those with gastritis only. The cagA gene can be used as a marker to detect the cag pathogenicity island. This DNA fragment seems to induce an increased inflammation in the gastric tissue via release of interleukin 8 by the epithelial cells. The association of this marker is strongly linked with ulcers compared with gastritis only (80% vs 55%, respectively). A number of other properties may be heterogeneous, but the low number of strains studied does not allow conclusions to be drawn.     

Beneficial effects of Helicobacter pylori eradication on migraine

BACKGROUND/AIMS: Migraine is a commonly unilateral throbbing headache, which has been associated with disorders of the vascular tone. Helicobacter pylori, the most relevant cause of gastritis and peptic ulcer, has been recently associated with a typical functional vascular disorder such as primary Raynaud phenomenon. The aim of this study was to assess the prevalence of H. pylori for patients affected by migraine and the effects of H. pylori eradication on migraine symptoms. METHODOLOGY: Two-hundred and twenty-five patients were consecutively enrolled between October 1996 and January 1997. H. pylori was assessed by 13C-urea breath test. Infected subjects were eradicated of the bacterium; frequency, intensity and duration of attacks of migraine were assessed during a 6 month follow-up period. RESULTS: H. pylori was detected in 40% of the patients. Eighty-three percent of the patients who underwent therapy were eradicated. Intensity, duration and frequency of attacks of migraine were significantly reduced in all eradicated patients. CONCLUSIONS: H. pylori is common in subjects with migraine. Bacterium eradication causes a significant decrease in attacks of migraine. The reduction of vasoactive substances produced during infection may be the pathogenetic mechanism underlying the phenomenon.     

Adhesion of Helicobacter pylori and Escherichia coli to human and bovine surface mucus cells in vitro

Helicobacter pylori shows in vivo a specific affinity for epithelial surface mucus cells (SMC) of the human stomach. We studied the in vitro adhesion of five different H. pylori strains and one non-pathogenic Escherichia coli-strain to (a) human antral SMC, obtained during gastroscopy; (b) human tumour SMC, from a carcinoma cell line (CRL 1739 AGS); and (c) bovine SMC, obtained from the abomasum. SMC of different origin were characterized by means of electron microscopy and immunohistochemistry, and showed similar main features: all cells showed intra-cellular structures like zymogens and PAS-positive mucin granules. HSMC were antibody-positive against epithelial cell markers. All five H. pylori strains adhered to human SMC (HSMC) and tumour SMC (TSMC). Only one strain additionally adhered to bovine SMC (BSMC). No adhesion to any of these cells was observed with E. coli. Adhesion in vitro is characterized by a close membrane-to-membrane association between H. pylori and the target cells. This phenomenon suggests a specific receptor-ligand interaction.