In vitro activities of natural products against oral Candida isolates from denture wearers

Background: Candida-associated denture stomatitis is a frequent infectious disease. Treatment of this oral condition is difficult because failures and recurrences are common. The aim of this study was to test the in vitro antifungal activity of pure constituents of essentials oils. -- Methods: Eight terpenic derivatives (carvacrol, farnesol, geraniol, linalool, menthol, menthone, terpinen-4-ol, and aterpineol), a phenylpropanoid (eugenol), a phenethyl alcohol (tyrosol) and fluconazole were evaluated against 38 Candida isolated from denture-wearers and 10 collection Candida strains by the CLSI M27-A3 broth microdilution method. -- Results: Almost all the tested compounds showed antifungal activity with MIC ranges of 0.03-0.25% for eugenol and linalool, 0.03-0.12% for geraniol, 0.06-0.5% for menthol, a-terpineol and terpinen-4-ol, 0.03-0.5% for carvacrol, and 0.06-4% for menthone. These compounds, with the exception of farnesol, menthone and tyrosol, showed important in vitro activities against the fluconazole-resistant and susceptible-dose dependent Candida isolates. -- Conclusions: Carvacrol, eugenol, geraniol, linalool and terpinen-4-ol were very active in vitro against oral Candida isolates. Their fungistatic and fungicidal activities might convert them into promising alternatives for the topic treatment of oral candidiasis and denture stomatitis.Funding: this work has been funded in part by projects GIC07 123-IT-222-07 (Departamento de Educacion, Universidades e Investigacion, Gobierno Vasco), S-PR09UN01 and S-PR10UN03 (Saiotek 2009 and 2010, Departamento de Industria, Comercio y Turismo, Gobierno Vasco)

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) in familial colorectal cancer

B ackground and aim: Congenital hypertrophy of the retinal pigment epithelium (CHRPE) is a pigmented fundus lesion associated with familial adenomatous polyposis (FAP). CHRPE prevalence has been reported to be increased in subjects with familial or sporadic non-polyposis colorectal cancer (CRC), suggesting that some individuals with non-polyposis CRC have an attenuated form of FAP. Other studies have not confirmed these clinical observations and have failed to identify mutations in the gene responsible for FAP, but the reason for the discrepancy in relation to CHRPE prevalence has not been resolved. We determined the prevalence of CHRPE in subjects without CRC (negative control cohort), subjects with FAP (positive control cohort), and subjects with familial non-polyposis CRC (test cohort). Method: A cohort study consisting of 37 negative control subjects, 9 positive control subjects with documented APC gene mutations, and 36 test subjects with familial non-polyposis CRC but no identified pathogenic APC gene mutation. The diagnosis of hereditary non-polyposis colon cancer was excluded in the test cohort by testing for microsatellite instability in tumour tissue. Results: None of the 37 people in the negative control group had CHRPE. Five of nine (56%) patients with FAP had multiple CHRPE lesions. None of the 36 subjects in the test cohort had CHRPE lesions. Conclusions: Ophthalmoscopy may contribute to risk assessment in families with FAP but not in familial non-polyposis CRC. Care must be exercised when interpreting pigmented fundus lesions because 8–13% of subjects in each of the cohorts had pigmented retinal lesions that were not CHRPE. Bilateral lesions and lesions with a depigmented halo␣were the hallmarks of CHRPE associated with FAP.Celia S. Chen, Kerry D. Phillips, Scott Grist, Graeme Bennet, Jamie E. Craig, James S. Muecke, Graeme K. Suther