Dietary intake of calcium, vitamins A and E and bleeding on probing in Sri Lankan preschoolers

OBJECTIVE

To determine the prevalence of gingival bleeding on probing and the associations between dietary intake of calcium, vitamins A and E and gingival bleeding on probing in Sri Lankan preschool children.

BASIC RESEARCH DESIGN

A cross-sectional study.

PARTICIPANTS

784 children aged 48-72 months attending preschools in the Kegalle district and their mothers/carers.

RESULTS

The prevalence of gingival bleeding on probing was 52.9%. A Poisson logistic regression model revealed that children with a high daily dietary intake of calcium were less likely to have gingival bleeding on probing than those with low intake (PR=0.80; 95%CI 0.64,0.98). Also prevalence of gingival bleeding was higher in children: with plaque on their teeth; whose mothers were not employed; or, were from families with three or more children.

CONCLUSIONS

The prevalence of gingivitis was high in the children and the findings suggest that high levels of dietary calcium intake are associated with reduced gingival bleeding in preschool children.

Managing aggression and violence: the clinician's role in contemporary mental health care

OBJECTIVE

From time to time misconceptions about violence risk assessment raise debate about the role mental health professionals play in managing aggression, with associated concerns about the utility of violence risk assessment. This paper will address some of the misconceptions about risk assessment in those with serious mental illness.

METHODS

The authors have expertise as clinicians and researchers in the field and based on their accumulated knowledge and discussion they have reviewed the literature to form their opinions.

RESULTS

This paper reflects the authors' views.

CONCLUSION

There is a modest yet statistical and clinically significant association between certain types of mental illness and violence. Debate about the appropriateness of clinician involvement in violence risk assessment is sometimes based on a misunderstanding about the central issues and the degree to which this problem can be effectively managed. The central purpose of risk assessment is the prevention rather than the prediction of violence. Violence risk assessment is a process of identifying patients who are at greater risk of violence in order to facilitate the timing and prioritisation of preventative interventions. Clinicians should base these risk assessments on empirical knowledge and consideration of case-specific factors to inform appropriate management interventions to reduce the identified risk.

Synthesis of starlike N-(2-hydroxypropyl)methacrylamide copolymers: potential drug carriers

Starlike HPMA copolymers were synthesized by conjugating semitelechelic poly[N-(2-hydroxypropyl)-methacrylamide] macromolecules (ST-PHPMA, arm) with PAMAM dendrimers (core: G2, G3, G4). ST-PHPMA was synthesized by chain transfer free radical polymerization, and the terminal -COOH was activated with N-hydroxysuccinimide. Doxorubicin (DOX) was introduced into the starlike HPMA copolymer to evaluate its potential as a drug delivery system. The polymers were characterized with SEC, NMR, and UV. Cytotoxicity of the DOX containing starlike HPMA copolymer was determined on an A2780 human ovarian carcinoma cell line and compared with DOX-containing linear HPMA copolymers. The rate of in vitro DOX release from polymer--DOX conjugates in the presence of cathepsin B (CP-B, lysosomal cysteine proteinase) was determined and correlated with cytotoxicity results.

trans-3,4-dihydroxy-anti-1,2-epoxy-1,2,3,4-tetrahydrodi- benz[a,j]acridine involvement in dibenz[a,j]acridine DNA adduct formation in mouse skin consistent with Ha-ras mutation patterns in tumors

Dibenz[a,j]acridine (DBA), is a N-heteropolycyclic aromatic environmental carcinogen found in complex combustion mixtures. The major route of DBA metabolic activation is reportedly through the trans-3,4-dihydroxy-3,4-dihydroDBA (DBA-3,4-DHD). The present studies were undertaken to determine the role of trans-3,4-dihydroxy-anti-1,2-epoxy-1,2,3,4-tetrahydroDBA (DBADE) in DBA activation pathway(s), the DNA bases involved in the binding of DBA to DNA, and whether the adducts produced are consistent with the mutation pattern in the Ha-ras gene. DBA (300 microg) or 50 microg synthesized (+/-)-DBADE was applied to the back of female Hsd:ICR(Br) mice. The mice were sacrificed 48 h later, and skin DNA was isolated, hydrolyzed, and analyzed with (32)P-postlabeling. Of the four adducts produced in vivo, adduct 1 was the major adduct for DBA (>50%) and adduct 2 was the major adduct for DBADE (89%). After the reaction of (+/-)-DBADE with purine nucleotides or calf thymus (CT) DNA in vitro, 100% of the DBADE-2'-dAMP adducts and 94% of DBADE-CT DNA adducts were chromatographically identical on TLC with adduct 2 and 86% of the DBADE-2'-dGMP adducts were chromatographically consistent with adduct 1 by (32)P-postlabeling. Papillomas were induced on the backs of mice by a single application of 0.2 micromol of DBA followed by twice-weekly application of 12-o-tetra-decanoylphorbol-13-acetate (TPA, 2 microg) for 24-26 weeks. Skin carcinomas were induced by twice weekly applications of DBA (0.1 micromol) on the backs of mice. A to T and G to T transversions were found in codons 12, 13, and 61 of the Ha-ras gene in the treated mouse skin carcinoma and papilloma DNA. The mutational spectra in the Ha-ras gene are consistent with the DNA binding of DBA to dG or dA in vivo. Thus, this research has indicated that DBADE plays an important role in DBA metabolic activation and DNA binding in mouse skin, and an alternative pathway through a bis-dihydrodiol-epoxide of DBA may also be involved.