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H. pylori is not usually present in dental plaque, indicating that oral-oral transmission of the infection could be due to intermittent esophageal reflux only.

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5.25% NaOCl showed a high antimicrobial activity against anaerobic bacteria. MTAD and Tetraclean showed a high action against both, strictly anaerobic and facultative anaerobic bacteria. Chlorexidine + Cetrimide (Cloreximid) showed the lowest antibacterial activity against both, facultative and strictly anaerobic bacteria tested.

Streptococcus salivarius TOVE-R has previously been reported as a successful competitor with Streptococcus mutans 10449S and Streptococcus sobrinus 6715-13 WT on the teeth of rats. We studied, in vitro, some possible bases for this competition, including hydrogen peroxide or catalase production, bacteriocin or enocin production, and growth rates. Growth rates were measured spectrophotometrically in both complex and defined media. We studied conditions of aerobic and anaerobic incubation; glucose and sucrose medium supplementation at three concentrations each; various initial pH's; singly- or doubly-inoculated cultures; and half-strength, normal, or double-strength broth used both fresh and as culture filtrates. TOVE-R grew as well as did mutans streptococci at acid pH, decidedly better at alkaline pH, and nearly twice as fast near neutral pH. The average doubling time for TOVE-R was about 0.5 hr, while that for the mutans streptococci was about 1.0 hr. When TOVE-R was grown together with a mutans streptococcus, the growth rate observed for the doubly-inoculated culture was equal to or less than that of TOVE-R alone, never greater. The presence and proportions of both organisms in mixed cultures were confirmed by plate counts, direct specific immunofluorescence, and Nomarski interference microscopy. There was no evidence, by any of the methods employed, to indicate the production of an inhibitory substance against mutans streptococci by TOVE-R, or vice versa. Also, there was no evidence that the faster growth rate of TOVE-R could be attributed to nutrient limitation of the mutans streptococci.(ABSTRACT TRUNCATED AT 250 WORDS)

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Sera of 1023 subjects belonging to categories at risk for AIDS, positive for HIV-1, were tested for antibodies to human T-cell leukemia virus (HTLV-1) by ELISA, Western blotting, and radioimmunoprecipitation (RIP) assay. Sera of these subjects were positive for antibodies to HTLV-1 in a percentage of 18.54%. Nine out of 18 sera from patients with AIDS had antibodies to HTLV-1 (50%). Sera of 207 intravenous drug abusers and 64 homosexual males, seronegative for HIV-1, were tested for antibodies to HTLV-1 and 6.7% of intravenous drug abusers and 7.8% of homosexual males were found to be HTLV-1 antibody positive, showing that HTLV-1 infection occurred independently of HIV-1 and HIV-2 infections. In fact the same HIV-1 seronegative patients were also tested for the presence of antibodies to HIV-2 and none of them was found to be positive.