Helicobacter pylori infection in indigenous families of Central America: serostatus and oral and fingernail carriage.

Helicobacter pylori infection remains one of the most common in humans, but the route of transmission of the bacterium is still uncertain. This study was designed to elucidate possible sources of infection in an isolated, rural population in Guatemala. A total of 242 subjects in family units participated in the study. A medical history, including a history of dyspepsia, was taken by a physician and immunoglobulin G antibodies to H. pylori were detected with the QuickVue (Quidel, San Diego, Calif.) onsite serology test. Overall, 58% of subjects were seropositive, with a positive relationship between mother and child (P = 0.02) and a positive correlation between the serostatuses of siblings (intraclass correlation coefficient = 0.63). There was no association between serostatus and gastric symptoms. Oral H. pylori was detected from periodontal pockets of various depths and the dorsum of the tongue by nested PCR. Eighty-seven percent of subjects had at least one oral site positive for H. pylori, with the majority of subjects having multiple positive sites. There was no association between periodontal pocket depth and the detection of H. pylori. Nested PCR was also used to detect H. pylori from beneath the nail of the index finger of each subject's dominant hand. Overall, 58% of subjects had a positive fingernail result, with a significant positive relationship between fingernail and tongue positivity (P = 0.002). In conclusion, the results of this study suggest that oral carriage of H. pylori may play a role in the transmission of infection and that the hand may be instrumental in transmission.

A comparison of intraoral antimicrobial effects of stabilized stannous fluoride dentifrice, baking soda/peroxide dentifrice, conventional NaF dentifrice and essential oil mouthrinse.

The intraoral antimicrobial activity of four commercial oral products-conventional NaF dentifrice (Crest), baking soda/peroxide/NaF dentifrice (Mentadent), essential oil mouthrinse (Listerine) and SnF2 dentifrice (Crest Plus Gum Care)-have been compared in three test regimens. Formulations were compared for their ability to suppress the regrowth and apical extension of dental plaque following toothbrushing during thirty hours of non-brushing where products were used as oral rinses (30-hour plaque regrowth model). Formulations were also compared for their ability to suppress the colony-forming units (cfu) of facultative anaerobic bacteria sampled from buccal gingival surfaces following use (Gingival Surface Microbial Index-GSMI model). Lastly, formulations were compared for effects in suppressing the glycolytic metabolic activity and regrowth activity of in vivo-treated dental plaques sampled at various periods following topical use and incubated under controlled ex vivo conditions (Plaque Glycolysis and Regrowth-PGRM model). In thirty-hour plaque regrowth testing, the rank ordered antimicrobial efficacy of formulations followed SnF2 > essential oils > NaF = water = baking soda/peroxide. In GSMI testing, all formulations were shown to suppress the cfu of facultative anaerobic bacteria relative to baseline, although SnF2 treatment was observed to reduce bacterial levels to a significantly greater degree than NaF dentifrice or baking soda/peroxide dentifrice up to two hours following brushing. In PGRM testing, the SnF2 dentifrice provided significant inhibition of bacterial metabolism and regrowth following topical application when compared with the NaF dentifrice as control. The baking soda/peroxide dentifrice provided no reduction in either bacterial metabolism or regrowth in PGRM. Previous studies had demonstrated modest effects for essential oil rinse in reducing PGRM plaque regrowth, with no effects for this treatment on plaque metabolism. Overall, these results demonstrate that SnF2 dentifrice provides substantial intraoral antimicrobial effects. The essential oil mouthrinse also exhibits significant intraoral antimicrobial effects, albeit apparently less than SnF2 dentifrice. The baking soda/peroxide dentifrice did not produce any antimicrobial effects following in vivo use compared with conventional dentifrice. These results provide mechanistic rationale for the chemotherapeutic efficacy of SnF2 and essential oil formulations in reducing gingivitis, while providing no support for the expectation of clinical efficacy for formulations containing baking soda and peroxide.

Poly I-Mercapto Poly C: antiviral, anticellular, and pharmacologic effects.

Thiolation of position 5 of some of the cytosine bases in polycytidylic acid results in the formation of mercaptopolycytidylic acid (MPC). Annealing of MPC to polyinosinic acid (Poly I) results in the formation of double-stranded Poly I-MPC. In this study we investigated the interferon inducing ability, in vivo toxic effects, effect on DNA synthesis, and the effects in human tumor cell lines of Poly I-MPC. Poly I-MPC was capable of inducing human alpha, beta and gamma interferons in the appropriate cell systems. In vivo toxicity was measured in mice, guinea pigs, and rabbits according to FDA guidelines. Weight loss and lethal and pyrogenic effects were markedly lower in Poly I-MPC treated animals than in those that received unmodified Poly I-Poly C. In contrast to the lack of an effect of Poly I-Poly C in human lymphocytes, Poly I-MPC inhibited DNA synthesis. It also inhibited colony formation and was cytotoxic in several human tumor cell lines. Poly I-MPC's ability to induce human alpha, beta and gamma interferons, to inhibit DNA synthesis and its effects in human tumor cell lines demonstrate the potential of this drug for future clinical studies, both as an antiviral and antitumor agent.