In vivo fluoride profiles at different sites of buccal and lingual enamel surfaces obtained by enamel biopsy of human maxillary first permanent molars in young adults

Twenty male volunteers, average age 24 years, participated in this study. Specimens were obtained by enamel biopsy using 5 microliters of 0.5 M HClO4 for 30 s. Using a regression curve, comparisons of fluoride concentrations were made at different depths. The fluoride concentrations (mean +/- SE) at a depth of 5 microns were highest in the distobuccal (1698 +/- 136), high in the mesiobuccal (1343 +/- 122), low in the distolingual (1119 +/- 107), and lowest in the mesiolingual sites (819 +/- 78). Of the interior enamels (> or = 10 microns in depth), the distobuccal site (1330 +/- 88 parts/10(6) F at 10 microns) had a higher-concentration than all other sites. The fluoride profiles were steepest to shallowest in the order: distobuccal, mesiobuccal, distolingual and mesiolingual. There were no correlations between the enamel fluoride concentrations and the fluoride concentration in parotid saliva. It was concluded that in vivo fluoride profiles of maxillary first molars reflect the wear of the tooth surface with age and the condition of dental plaque deposition, and, to some extent, the site-specific distribution of saliva between buccal and lingual surfaces.     

Hemostasis and blood requirements in orthotopic liver transplantation with and without high-dose aprotinin

Immunization is a safe and cost-effective method to protect adult patients against many diseases, including hepatitis B, pneumococcal infections, and influenza. Despite this fact, only 10% to 40% of adults in the United States who would benefit have been immunized. Approximately 62% to 92% of patients who develop a disease preventable by vaccination have visited an outpatient clinic at least once in the 3 years preceding their illness. Efforts to educate providers about immunization guidelines have not increased immunization rates. In this report, we propose using the preanesthesia clinic as an alternative site to screen, identify, and immunize adults at risk. We also discuss three vaccines that could be offered to patients and analyze the efficacy of the vaccines.     

Bone morphogenetic protein-7 (osteogenic protein-1, OP-1) and tooth development

The photodynamic effects of temoporfin (meso-tetrahydroxyphenylchlorin, mTHPC) and merocyanine 540 (MC540) in murine myeloid leukemia M1 and WEHI 3B (JCS) cells were compared. The mTHPC was found to be more potent and selective. At a lethal dosage of 90% killing (LD90), only 1.3 microM of mTHPC and 4.2 kJ/m2 of light irradiation was required, which was a 20-fold lower drug concentration and 11-fold smaller light dose than that required when using MC540. Meanwhile, three times less, or 15%, of the coincubated erythrocytes were destroyed by mTHPC than by MC540. Confocal micrographs showed that both drugs accumulated diffusely inside the cytoplasm in a very similar fashion, but mTHPC induced a more extensive apoptosis in photosensitized JCS cells. For example, at LD90, mTHPC practically killed all JCS cells via apoptosis and cleaved the DNA to extremely small 150 base-pair fragments. In contrast, among the JCS cells killed by MC540, about 88% died via apoptosis and large DNA fragments were abundant. Relative to MC540, the ability of mTHPC to trigger large-scale and thorough apoptosis in leukemia cells may help explain its potency and selectivity.     

Chronic residential crowding and children's well-being: an ecological perspective

Chronic residential crowding is associated with difficulties in behavioral adjustment at school, poor academic achievement, heightened vulnerability to the induction of learned helplessness, elevated blood pressure, and impaired parent-child interpersonal relationships among a sample of working-class, 10-to 12-year-old children living in urban India. The significant main effects of residential crowding on blood pressure and learned helplessness are moderated by gender. Residential crowding is positively associated with blood pressure only among boys and with helplessness only among girls. All analyses statistically control for household income. We then demonstrate that perceived parent-child conflict functions as an underlying, intervening process that largely accounts for several correlates of household crowding among children.