Caries Risk Prediction Models in a Medical Health Care Setting.

Despite development of new technologies for caries control, tooth decay in primary teeth remains a major global health problem. Caries risk assessment (CRA) models for toddlers and preschoolers are rare. Among them, almost all models use dental factors (e.g., past caries experience) to predict future caries risk, with limited clinical/community applicability owing to relatively uncommon dental visits compared to frequent medical visits during the first year of life. The objective of this study was to construct and evaluate risk prediction models using information easily accessible to medical practitioners to forecast caries at 2 and 3 y of age. Data were obtained from the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) mother-offspring cohort. Caries was diagnosed using modified International Caries Detection and Assessment System criteria. Risk prediction models were constructed using multivariable logistic regression coupled with receiver operating characteristic analyses. Imputation was performed using multiple imputation by chained equations to assess effect of missing data. Caries rates at ages 2 y (n = 535) and 3 y (n = 721) were 17.8% and 42.9%, respectively. Risk prediction models predicting overall caries risk at 2 and 3 y demonstrated area under the curve (AUC) (95% confidence interval) of 0.81 (0.75-0.87) and 0.79 (0.74-0.84), respectively, while those predicting moderate to extensive lesions showed 0.91 (0.85-0.97) and 0.79 (0.73-0.85), respectively. Postimputation results showed reduced AUC of 0.75 (0.74-0.81) and 0.71 (0.67-0.75) at years 2 and 3, respectively, for overall caries risk, while AUC was 0.84 (0.76-0.92) and 0.75 (0.70-0.80), respectively, for moderate to extensive caries. Addition of anterior caries significantly increased AUC in all year 3 models with or without imputation (all P < 0.05). Significant predictors/protectors were identified, including ethnicity, prenatal tobacco smoke exposure, history of allergies before 12 mo, history of chronic maternal illness, maternal brushing frequency, childbearing age, and so on. Integrating oral-general health care using medical CRA models may be promising in screening caries-susceptible infants/toddlers, especially when medical professionals are trained to "lift the lip" to identify anterior caries lesions.

Deleterious effects of short-term, high-intensity exercise on immune function: evidence from leucocyte mitochondrial alterations and apoptosis.

BACKGROUND: Although moderate exercise can benefit health, acute and vigorous exercise may have the opposite effect. Strenuous exercise can induce alterations in the physiology and viability of circulating leucocytes, which have a causal relationship with exercise-induced immune distress. OBJECTIVES: To investigate the use of mitochondrial transmembrane potential (MTP), a functional marker of the energy and viability status of leucocytes, for monitoring the immunomodulating effects of short-term, high-intensity exercise. METHODS: 12 healthy volunteers with a mean Vo(2)max of 70.4 ml/kg/min carried out 3 consecutive days of high-intensity exercise (85% of Vo(2)max for 30 min every day). Blood samples were collected at multiple time points immediately before and after each exercise session and at 24 and 72 h after the completion of exercise. Leucocyte MTP, apoptosis and circulatory inflammation markers were measured by flow cytometry and enzyme-linked immunosorbent assays. RESULTS: MTP of peripheral blood leucocytes had declined immediately after the first exercise session and remained subnormal 24 h later. It did not normalise until 72 h after exercise. The sequential changes in MTP were consistent among the three leucocyte subpopulations (polymorphonuclear neutrophils, lymphocytes and monocytes) and were significant (p<0.05). Leucocytes displayed a gradual and incremental change in their propensity for apoptosis during and after exercise. Similarly, plasma concentrations of tumour necrosis factor-alpha and soluble Fas ligand were raised during the exercise sessions and had not normalised by 72 h after the completion of exercise. Correlation between changes in leucocyte MTP and plasma concentrations of tumour necrosis factor-alpha and soluble Fas ligand was variable, but significant for polymorphonuclear neutrophils and lymphocytes (p<0.05). CONCLUSIONS: Short-term, high-intensity exercise can lead to a significant and prolonged dysfunction of the mitochondrial energy status of peripheral blood leucocytes, which is accompanied by an increased propensity for apoptosis and raised pro-inflammatory mediators. These results support the immunosuppressive effects of excessive exercise and suggest that MTP is a useful marker of these effects.

In vitro comparisons of SENCAR and BALB/c primary epidermal cells.

Grafting experiments show that the enhanced sensitivity of the SENCAR mouse to skin carcinogenesis by initiation and promotion is a property of the skin itself, suggesting the usefulness of in vitro studies to elucidate the mechanism. Such studies have indicated that cultured epidermal cells of SENCAR mice and the resistant BALB/c strain are remarkably similar in a variety of respects. DNA repair and carcinogen binding are quantitatively similar in cultured cells of SENCAR and more resistant mouse strains. Epidermal Langerhans cell (LC) number and LC-mediated functions were indistinguishable in SENCAR and BALB/c mice. Primary epidermal cells cultured in the presence of various concentrations of 12-O-tetradecanoylphorbol-13-acetate (TPA), retinoic acid, epidermal growth factor (EGF), hydrocortisone, or fluocinolone acetonide failed to reveal differences in growth between BALB/c and SENCAR cells. Cells from these animals bound comparable amounts of EGF with similar kinetics, and the modulation of this binding by TPA and retinoic acid was indistinguishable between strains. Spontaneous expression of infectious, endogenous xenotropic type C RNA virus at very low levels could be demonstrated in primary BALB/c epidermal cells and both BALB/c and SENCAR epidermal lines resistant to Ca2+-induced terminal differentiation. The number of foci of initiated cells after exposure to carcinogens in vivo or in vitro did not differ significantly between SENCAR and BALB/c, suggesting that SENCAR sensitivity is primarily to promotion. However, there are qualitative differences between SENCAR and BALB/c foci. The appearance of foci of cells resistant to terminal differentiation in untreated SENCAR cultures supports the evidence from in vivo studies for the existence of a constitutively initiated cell population in SENCAR mouse skin.