Association between dental anxiety and periodontal attachment loss

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A disease-causing mutation K240E disrupts ferroportin trafficking by SUMO (ferroportin SUMOylation)

Ferroportin (Fpn/IREG1/MTP1) is the only known transporter mediating iron efflux from epithelial cells and macrophages, and thus regulates how much iron is released into the circulation. Consequently, Fpn mutations are associated with haemochromatosis. Fpn itself is post-translationally regulated by hepcidin (Hepc) which induces its redistribution and degradation in a ubiquitin-dependent process. Together, the two proteins appear to be the nexus for iron homeostasis. Here we show that a rare gain-of-function mutation (K240E) that is associated with iron overload, impedes Fpn binding and subcellular trafficking by the small ubiquitin-like modifier (SUMO). Whereas wild-type Fpn is ensconced within vesicular bodies, the FpnK240E mutant appeared diffused within the cell when co-expressed with SUMO. Furthermore, compared with wild type Fpn, the sumoylation-defective mutant was constitutively-active, resulting in a lower intracellular labile iron pool than the former. These findings suggest that SUMO may regulate iron homeostasis by controlling Fpn trafficking

A community study on the relationship of stress and periodontitis

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A community study on the relationship of dental anxiety with oral health status and oral health-related quality of life

Objective: To investigate the relationship of dental anxiety with oral health status and oral health-related quality of life (OHQoL) among dentate subjects living in Hong Kong. Methods: One thousand Hong Kong residents who were aged 25-64 years and predominantly Chinese were asked to complete the Chinese short-forms of the Dental Anxiety Inventory (SDAxI) and Oral Health Impact Profile (OHIP-14S). Dental (DMFT index) and periodontal statuses [full-mouth clinical attachment level (CAL)] were also assessed. Results: Ninety-six (9.6%; mean SDAxI, 9.6), 799 (79.9%; mean SDAxI, 15.0), and 105 (10.5%; mean SDAxI, 27.4) participants had low, average, and high dental anxiety, respectively. The mean DMFT/CAL scores of each SDAxI subgroup were 8.5/1.4, 9.3/1.9, and 9.8/3.6, respectively. The corresponding mean OHIP-14S scores for each SDAxI subgroup were 4.0, 8.1, and 13.2, respectively. Post hoc analysis, adjusted for possible confounding factors, revealed statistically significant differences in DMFT and CAL scores in subjects with low versus high level of SDAxI, and significant differences in OHIP-14S scores between all 3 SDAxI categories. Conclusion: The trait disposition of dental anxiety may be a significant risk indicator of poor dental and periodontal status and is associated with a worse OHQoL. © 2007 The Authors.postprin

A community study on the relationship between stress, coping, affective dispositions and periodontal attachment loss

Background: Psychological factors may increase the risk for periodontal diseases. Contemporary conceptualization of the stress process supports the evaluation of stress at three levels: stressors, moderating and mediating factors, and stress reactions. Objective: This study was undertaken to investigate the relationship of periodontal disease in terms of clinical attachment level (CAL) to psychosocial stress, making reference to the major components of stress process. Methods: A cross-sectional study of 1000 subjects aged 25-64 years in Hong Kong was conducted. Subjects were asked to complete a set of questionnaires measuring stressors including changes, significant life event and daily strains, stress reactions including physiological and affective responses, and coping and affective dispositions. CAL was assessed. Results: Individuals with high mean CAL values had higher scores on the job and financial strain scales than periodontally healthy individuals (P < 0.05), after adjusting for age, gender, cigarette smoking and systemic disease. Depression, anxiety trait, depression trait, problem-focused coping, and emotion-focused coping were also related to CAL. Logistic regression analysis indicated that all these factors were significant risk indicators for periodontal attachment loss, except problem-focused coping, which reduced the odds of CAL. Individuals who were high emotion-focused copers, low problem-focused copers, trait anxious, or trait depressive had a higher odds of more severe CAL. Conclusion: Chronic job and financial strains, depression, inadequate coping, and maladaptive trait dispositions are significant risk indicators for periodontal attachment loss. Adequate coping and adaptive trait dispositions, evidenced as high problem-focused coping and low anxiety/ depression trait, may reduce the stress-associated odds. © Blackwell Munksgaard, 2006.postprin

Oral health-related quality of life and periodontal status

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Scientific discovery: that-what’s and what-that’s

In this paper I defend Kuhn’s view of scientific discovery, which involves two central tenets, namely (i) that a scientific discovery always requires a discovery-that (i.e., the observation of X) and a discovery-what (i.e., the correct conceptualisation of X); and (ii) that there are two kinds of scientific discovery, resulting from the temporal order of the discovery-that and the discovery-what. I identify two problems with Kuhn’s account and offer solutions to them from a realist stance. I also discuss alternatives to Kuhn’s account

Role of Dietary Flavonoids in Iron Homeostasis

Balancing systemic iron levels within narrow limits is critical for human health, as both iron deficiency and overload lead to serious disorders. There are no known physiologically controlled pathways to eliminate iron from the body and therefore iron homeostasis is maintained by modifying dietary iron absorption. Several dietary factors, such as flavonoids, are known to greatly affect iron absorption. Recent evidence suggests that flavonoids can affect iron status by regulating expression and activity of proteins involved the systemic regulation of iron metabolism and iron absorption. We provide an overview of the links between different dietary flavonoids and iron homeostasis together with the mechanism of flavonoids effect on iron metabolism. In addition, we also discuss the clinical relevance of state-of-the-art knowledge regarding therapeutic potential that flavonoids may have for conditions that are low in iron such as anaemia or iron overload diseases

Formulation of Thermosensitive Hydrogel Containing Cyclodextrin for Controlled Drug Delivery of Camptothecin

Purpose: To formulate and evaluate temperature-sensitive, controlled-release camptothecin hydrogel for anticancer drug delivery.Method: Temperature-sensitive hydrogel based on chitosan/β-glycerophosphate (β-GP)/β-cyclodextrin (β-CD) was prepared by crosslinking method. The formulations were characterized by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), gelation time, and viscometry, as well as for controlled release. The formulation, containing camptothecin, was studied by MTT assay on tumor cell MCF-7. The effectiveness of treatment was measured in terms of controlled tumor growth inhibition (TGI).Results: The hydrogel formulation showed good properties in terms of pH, gelation, viscosity and invitro release. The gelation temperature and viscosity of the formulation was optimum. Camptothecin (CPT) released from the hydrogel (TF8) over 8 h in pH 7.4 buffer ranged from 38.97 - 92.5 %, and varied according to the composition of the hydrogels. Release of camptothecin was lowest from preparations without cyclodextrins. Tumor growth inhibition activity of CPT in MCF-7 cell was highest for the formulation containing 1 % chitosan, 8 % β-GP and 1 % β-CD while no inhibition was observed for the blank temperature sensitive hydrogel formulation.Conclusion: These formulations are a promising and more effective delivery system that can be developed to serve as an alternative to the conventional system for anticancer drug delivery.Keywords: Hydrogel, Chitosan, β-Glycerophosphate, β-Cyclodextrin, Camptothecin, MCF-7 cell lin

Non-surgical periodontal therapy improves oral health-related quality of life

AIM: The influence of non-surgical periodontal therapy on oral health-related quality of life (OHQoL) was investigated. MATERIALS AND METHODS: Sixty-five Chinese adults (25 men, mean 47.4 years) with moderate-to-advanced chronic periodontitis were recruited. All received oral hygiene instructions (OHI) and non-surgical periodontal treatment in a quadrant-wise approach, followed by recalls at 1, 3, 6, 9 and 12 months post treatment, when OHI and prophylaxis were repeated. Clinical parameters were recorded, and oral health impact profile short-form (OHIP-14S) was administered at all time points. RESULTS: Moderate-to-deep sites (>/=4 mm) decreased from 31.0% to 3.0% at 12 months post treatment (p < 0.005) which corresponded well with reductions in plaque, 72.8% to 25.4% (p < 0.005) and bleeding on probing, 86.3% to 32.0% (p < 0.005). Median OHIP-14S scores gradually reduced from 17 at baseline to 14 over the first 6 months and remained plateaued at 12-month post treatment (p < 0.005). Improvements in subdomains of physical pain, psychological discomfort and psychological disability accounted for the changes. CONCLUSION: This study demonstrates that OHQoL, in particular, pain and psychological subdomains, improvement was associated with non-surgical periodontal therapy responses. Clinicians could capitalize upon the positive psychological OHQoL impacts of mechanical periodontal treatment for subsequent patient-centred motivation during maintenance therapy.postprin