Assessment of dental student studying strategies.

This study evaluated the studying strategies of second-year and third-year dental students as related to end-quarter exam preparation. Focus groups were convened to elicit current student studying strategies that were incorporated into a three-question survey and administered to second- and third-year students. Strategic use of study resources was rank ordered in the first question; course characteristics influencing study prioritization were rank ordered in the second question; and a third question addressed strategic time management. Overall, both second- and third-year students ranked the studying resource "notepool" first, although students of high academic standing ranked "texts and syllabi" first. Regarding course characteristics, both classes gave high ranking to "instructor expectations," "performance on midterm," and "course structure." Second-year students rated "performance on midterm" as significantly more important to prioritization than did third-year students (p = 0.01, t-test). As to time management, a statistically significant number of second-year students (p < 0.01, chi-square) ranked "studying for exams mid-quarter" first while third-year students (p = 0.05) ranked "studying the week before finals" first. Second- and third-year students of high academic standing indicated that they began studying at the beginning of the quarter. The data suggest that studying strategies change as students progress in school and that students of high and low academic ranking differ in the strategies they employ.

Effect of whole oral bacteria and extracted lipopolysaccharides on peripheral blood leukocyte interleukin-2 receptor expression.

Expression of the interleukin-2 receptor (IL-2R) on T cells is the molecular mechanism that initiates the G0 to G1 transition and is the critical first step for T cell proliferation in response to antigen. The effect of whole periodontal bacteria and lipopolysaccharides (LPS) on peripheral blood mononuclear cell (PBMC) IL-2R expression was examined in vitro. LPS induced a modest but significant increase in high affinity IL-2R alpha/beta (p55/p75 positive) expression on PBMC over untreated cells after 48 h culture. Addition of LPS to PBMC cultures depleted of monocytes had no effect on IL-2R expression compared to untreated cultures. Interleukin-1 (IL-1) caused a similar effect to LPS in 48 h PBMC cultures but IL-1 also increased high affinity IL-2R expression in cultures depleted of adherent mononuclear cells. When antibody to IL-1 was simultaneously added with LPS to PBMC cultures, the high affinity IL-2R inductive effect was reversed at 48 h, suggesting that the LPS effect on PBMC IL-2R was indirect, via monocytes. Whole pathogenic oral bacteria cultured with PBMC at high (100:1), but not low (10:1) bacteria:PBMC ratios had a similar effect to LPS, inducing high affinity IL-2R expression at 48 h. Increases in soluble IL-2R alpha were also measured in supernatants of PBMC incubated with periodontal bacteria compared to untreated controls. In this system, a critical threshold of bacteria was required to activate PBMC perhaps related to the quantity of cell-surface LPS presented to adherent mononuclear cells.