Halitosis and Helicobacter pylori infection.

There is disagreement about a possible relationship between Helicobacter pylori (H. pylori) infection and objective halitosis, as established by volatile sulfur compounds (VSCs) in the breath. Many studies related to H. pylori used self-reported halitosis, a subjective and unreliable method to detect halitosis. In this study a possible relation between H. pylori and halitosis was evaluated, using an objective method (gas chromatography, GC) to detect the VSCs, responsible for the halitosis. The levels of the VSCs hydrogen sulfide (H(2)S), methyl mercaptan (MM) and dimethyl sulfide (DMS) were measured in mouth breath and in stomach air of 11 H. pylori positive patients and of 38 H. pylori negative patients, all with gastric pathology. Halitosis was also established by organoleptic scoring (OLS) of mouth-breath. The levels of H(2)S, MM and DMS in the mouth-breath and stomach air of the H. pylori positive patients did not differ significantly from those of the H. pylori negative patients. OLS of the mouth-breath resulted in 9 patients with halitosis, 1 out of the H. pylori positive group and 8 out of the H. pylori negative group, which is not statistically different. The concentrations of the VSCs in stomach air were in nearly all cases below the thresholds of objectionability of the various VSCs, indicating that halitosis does not originate in the stomach. The patients with gastric pathology were also compared with control patients without gastric pathology and with normal volunteers. No significant differences in VSCs in mouth breath were observed between these groups. Thus, in this study no association between halitosis and H. pylori infection was found. Halitosis, as established by GC and OLS, nearly always originates within the oral cavity and seldom or never within the stomach.

A systematic comparison of triple therapies for treatment of Helicobacter pylori infection with proton pump inhibitor/ ranitidine bismuth citrate plus clarithromycin and either amoxicillin or a nitroimidazole.

BACKGROUND: Triple therapies with proton pump inhibitor/ranitidine bismuth citrate (RBC), clarithromycin (C) and either amoxicillin (A) or a nitroimidazole (I) are widely accepted as treatment for Helicobacter pylori infection. However, it is not clear which of these antibiotic combinations should be preferred. AIM: To evaluate whether there is a difference in efficacy between triple therapies with proton pump inhibitor/RBC, clarithromycin and either amoxicillin or a nitroimidazole. METHODS: The literature was examined for randomized trials comparing proton pump inhibitor/RBC-C-A and proton pump inhibitor/RBC-C-I. Studies were grouped according to the type of acid inhibitor used (proton pump inhibitor or RBC) and differences between pooled cure rates were calculated. RESULTS: Forty-seven studies were identified: seven using RBC, 39 using proton pump inhibitor, one using both. RBC-C-I was somewhat superior to RBC-C-A, although this difference only reached statistical significance in intention-to-treat analysis. Overall, proton pump inhibitor-C-I and proton pump inhibitor-C-A were equally effective, but in nitroimidazole-susceptible strains, proton pump inhibitor-C-I performed better, in nitroimidazole-resistant strains, proton pump inhibitor-C-A performed better. No serious side-effects were reported and pooled drop-out rates were equal. CONCLUSIONS: In general, proton pump inhibitor-C-I and proton pump inhibitor-C-A are equally effective and therefore other factors such as local prevalence of resistant strains, cost of therapy and options for second-line treatment should determine which regimen should be preferred. When using RBC, the RBC-C-I combination is somewhat superior to RBC-C-A.

Review article: treatment of Helicobacter pylori infection with ranitidine bismuth citrate- or proton pump inhibitor-based triple therapies.

Triple therapy, combining a proton pump inhibitor with clarithromycin (C) and either amoxycillin (A) or a nitro-imidazole (I) is the standard in Helicobacter pylori eradication therapy. Recently, triple therapies based on ranitidine bismuth citrate (RBC) have emerged as an alternative. This review examines the current literature for studies directly comparing proton pump inhibitor- with RBC-based triple therapies. Seventeen studies were identified, of which three have been published as a full paper. Eradication rates in an intention-to-treat analysis ranged from 51 to 98%. No large difference in cure rates between the different regimens was demonstrated, although the RBC-I-C combination was somewhat superior. No definite conclusions could be made about the impact of metronidazole or clarithromycin resistance since only three studies performed a formal resistance analysis. No serious side-effects were reported, and dropout rates were equal for the two regimens. Both RBC- and proton pump inhibitor-based triple therapies are highly effective. If one prefers a imidazole/clarithromycin combination the evidence presented here suggests that RBC should be used instead of a proton pump inhibitor. Larger studies comparing both forms of triple therapy, using proper resistance analysis, are needed before final conclusions can be reached regarding efficacy in the setting of bacterial resistance.

Antral glutathione concentration and glutathione S-transferase activity in patients with and without Helicobacter pylori.

Previously we demonstrated an inverse relation between cancer of the gastrointestinal tract and glutathione S-transferase activity of the gastrointestinal mucosa. Chronic infection with H. pylori has been associated with an increased risk of gastric cancer. The aim of this study was to investigate the levels of glutathione and glutathione S-transferase activity in H. pylori-infected and noninfected antral mucosa. Glutathione and glutathione S-transferases were measured in antral biopsies of patients with nonulcer dyspepsia without H. pylori infection (A), with prior H. pylori infection who became H. pylori negative after eradication therapy (B) and with proven H. pylori infection (C). Glutathione concentration and glutathione S-transferase activity in group A were 31.0 (range 6.0-59.6) nmol/mg protein and 810 (range 165-1312) nmol/min/mg protein, in group B 27.0 (range 5.0-53.8) nmol/mg protein and 745 (range 403-1199) nmol/min/mg protein, and in group C 18.5 (range 1.6-55.8) nmol/mg protein and 572 (range 144-1047) nmol/min/mg protein, respectively. The glutathione and glutathione S-transferase values were significantly lower in patients infected with H. pylori than in patients who were H. pylori negative.

Bismuth-based quadruple therapy for Helicobacter pylori - a single triple capsule plus lansoprazole.

BACKGROUND: Recently a new 'all in one' single capsule with the three components of bismuth-based triple therapy became available in trials for treating Helicobacter pylori. AIM: To investigate the efficacy and tolerability of this new capsule when combined with lansoprazole. METHODS: A total of 66 consecutive infected patients from a single centre received two single triple capsules four times daily and lansoprazole 30 mg b.d. for 7 days. Each capsule contained 60 mg of bismuth subcitrate, 125 mg of tetracycline and 125 mg of metronidazole. Endoscopy with biopsies for CLO-test, histology and culture from antrum and corpus was performed before and at least 5 weeks after treatment. RESULTS: The per protocol cure rate was 56/64 (88%, 95% CI: 79-95%); by intention-to-treat 56/65 (86%, 95% CI: 78-95%). The per protocol cure rate in metronidazole sensitive strains was 40/43 (93%, 95% CI: 85-100%); in resistant strains 5/9 (56%, 95% CI: 23-88%). There was one drop-out due to adverse events. CONCLUSIONS: It is possible to combine the components of bismuth-based triple therapy into a single capsule. Based on the results it can be assumed that the capsule releases its content in the stomach. When combined with lansoprazole it reaches high cure rates, especially in metronidazole sensitive strains. This new approach simplifies bismuth-based anti-Helicobacter therapy.

Verification of the position of the phosphate group in some synthetic phosphopeptides by fast-atom bombardment and tandem mass spectrometry.

Some synthetically obtained linear and cyclic phosphopeptides of low molecular weight have been studied by fast-atom bombardment and tandem mass spectrometry to verify the position of the phosphate group in these compounds. Based upon the occurrence/non-occurrence of loss of phosphoric acid from low abundance fragment ions induced by low- and high-energy collisions with target gases, it is shown that the position of the phosphate group in the phosphopeptides studied can be determined unequivocally.

The value of tests predicting renovascular hypertension in patients with renal artery stenosis treated by angioplasty.

The aim of this study was to evaluate tests predicting renovascular hypertension. This was done by relating the results of renal vein renin tests, the captopril test, and renal scintigraphic tests to the blood pressure outcome 12 months after relief of renal artery stenosis by percutaneous transluminal renal angioplasty in 31 patients. Cure was seen in eight (26%). Improved blood pressure was obtained in 12 patients (39%), and in 11 patients (35%), the result for blood pressure was a failure. The accuracies of the two mathematical models used to analyze the renal vein renin assays were 44% and 60%. The captopril test showed a sensitivity of 36% and an accuracy of 43%. Renal captopril technetium Tc 99m-labeled pentetic acid scintigraphy gave a sensitivity of 60%. Stepwise logistic regression analysis of clinical variables in relation to blood pressure response revealed age as the only factor significantly related to blood pressure outcome. We conclude that the tests used are unfit for helping select patients for percutaneous transluminal renal angioplasty and that age may have an important influence on outcome.

Synthesis of structural elements of the capsular polysaccharides of Streptococcus pneumoniae types 6A and 6B.

O-alpha-d-Glucopyranosyl-(1----3)-alpha, beta-L-rhamnopyranose (15), O-alpha-D-galactopyranosyl-(1----3)-O-alpha-D-glucopyranosyl-(1----3)-al pha, beta-L-rhamnopyranose (17), O-alpha-D-galactopyranosyl-(1----3)-O-alpha-D-glucopyranosyl-(1----3)- O-alpha-L-rhamnopyranosyl-(1----3)-D-ribitol (23), and O-alpha-D-galactopyranosyl-(1----3)-O-alpha-D-glucopyranosyl-(1----3)- O-alpha-L-rhamnopyranosyl-(1----4)-D-ribitol (27), which are structural elements of the capsular polysaccharides of Streptococcus pneumoniae types 6A and 6B ([----2)-alpha-D-Galp-(1----3)-alpha-D-Glcp-(1----3)-alpha-L-Rhap- (1----X)- D-Rib-ol-(5-P----]n; 6A X = 3, 6B X = 4), have been synthesised. Ethyl 3-O-allyl-2,4,6-tri-O-benzyl-1-thio-beta-D-glucopyranoside (3) was coupled with benzyl 2,4-di-O-benzyl-alpha-L-rhamnopyranoside (4), and subsequent deallylation (----14) and debenzylation gave 15. Condensation of 14 with ethyl 2,3,4,6-tetra-O-benzyl-1-thio-beta-D-galactopyranoside (2) followed by debenzylation gave 17. Acetylation of 17 followed by removal of AcO-1, conversion into the imidate, coupling with 1,2,4,5-tetra-O-benzyl-D-ribitol (11), deacetylation, and debenzylation gave 23. Coupling of the imidate with 1-O-allyloxycarbonyl-2,3,5-tri-O-benzyl-D-ribitol (12) followed by deallyloxycarbonylation, deacetylation, and debenzylation yielded 27.