Kcm Leung

The efficacy of cevimeline hydrochloride in the treatment of xerostomia in Sjögren’s syndrome in southern Chinese patients: a randomised double-blind, placebo-controlled crossover study

Cevimeline hydrochloride, a specific agonist of the M3 muscarinic receptor, is beneficial in the treatment of symptoms of xerostomia and xerophthalmia associated with Sjögren’s syndrome (SS). Cevimeline has not been evaluated in southern Chinese patients. Furthermore, the effects of cevimeline on health-related quality of life and oral health status are not known. In this randomised, double-blind, placebo-controlled crossover study, patients received cevimeline 30xa0mg or matched placebo three times per day over 10xa0weeks followed by a 4-week washout period before treatment crossover. Participants self-completed the following questionnaires: Xerostomia Inventory (XI), the General Oral Health Assessment Index (GOHAI), the Ocular Surface Disease Index (OSDI) and the Medical Outcomes Short Form (SF-36). Clinical assessments included sialometry, examination of the oral cavity for the degree of xerostomia and dental complications of xerostomia. Fifty patients (22 primary SS and 28 secondary SS) were enrolled in the trial. Forty-four patients completed the study. There was a significant improvement in the XI and GOHAI scores as well as the objective rating of xerostomic signs of the oral cavity after treatment with cevimeline. However, there was no improvement in salivary flow rates and dry eye symptoms. SS patients had lower SF-36 scores, but these did not improve after treatment with cevimeline.

Supra-gingival microbiota in Sjögren’s syndrome

The aim of this study was to investigate the microbiota of noncaries associated supra-gingival plaque (SGP) microbiology in Sjögren’s syndrome (SS). Stimulated whole saliva (SWS) and full-mouth SGP on intact tooth surfaces were collected from 26 primary (p) SS, 27 secondary (s) SS, and 29 control subjects for selective culture of lactobacilli, mutans streptococci, and aerobic and facultatively anaerobic gram-negative rods (AGNR). Predominant cultivable anaerobes from SGP of 11 randomly selected subjects from each group were investigated. Clinical and sialometric data were also collected. SS sufferers had significantly lower SWS flow rate and higher mean DMFT (decayed, missing, filled teeth), while pSS subjects also had lower SWS pH and fewer standing teeth. Lactobacillus acidophilus levels in SWS (Pu2009=u20090.012) and SGP (Pu2009<u20090.0001) were significantly elevated in pSS sufferers compared with sSS individuals and controls. AGNR isolation was uncommon. SS sufferers had significantly lower proportion of gram-negative species (Pu2009=u20090.047). Non-oral species were isolated in greater proportions from pSS SGP (Pu2009=u20090.007). Subjects with pSS harbored increased levels of L. acidophilus and non-oral species, while SS sufferers generally had lower proportions of gram-negative species. The microbial composition of noncaries associated SGP indicates a potential source of increased caries risk in SS.

Estrogenic phenol and catechol metabolites of PCBs modulate catechol-o-methyltransferase expression via the estrogen receptor: Potential contribution to cancer risk

Commercial PCB mixtures have been shown to induce liver tumors in female rats and this effect has been attributed to the effects of PCBs on estrogen metabolism. Catechol metabolites of PCBs are potent inhibitors of COMT activity and are likely to contribute significantly to reduced clearance of genotoxic catechol metabolites of estrogen. The effect of PCB metabolites on COMT expression in cultured cells was investigated to explore potential mechanisms by which PCB exposure alters catechol estrogen clearance. We hypothesize that estrogenic PCB metabolites may contribute to reduction of COMT expression via interaction with the estrogen receptor. To test this hypothesis, human MCF-7 cells were exposed to PCB analogues and the expression of COMT determined. Western blot analysis demonstrated that COMT protein levels were statistically significantly reduced by both the phenolic and the catechol compounds, an effect which was abolished by the anti-estrogen, ICI182780. The above suggests that COMT levels may be reduced by estrogenic PCB metabolites, via interactions between PCB metabolites and the ER. It supports the hypothesis that both phenolic and catechol metabolites of PCBs may contribute to PCB-mediated carcinogenesis through reduction of COMT levels and activities and subsequent reduction in clearance of endogenous and xenobiotic catechols.