In vitro activity of linezolid in combination with photodynamic inactivation against Staphylococcus aureus biofilms

Background: Biofilm infections are a major challenge in medical practice. Bacteria that live in a biofilm phenotype are more resistant to both antimicrobial therapy and host immune responses compared to their planktonic counterparts. So, there is need for new therapeutic strategies to combat these infections. A promising approach [known as Photodynamic Inactivation [PDI]] to kill bacteria growing as biofilms uses light in combination with a photosensitizer to induce a phototoxic reaction which produces reactive oxygen species that can destroy lipids and proteins causing cell death. PDI does not always guarantee full success, so, combination of PDI with antibiotics may give increased efficiency. This study aimed to determine if PDI was effective in the eradication of Staphylococcus aureus [S. aureus] biofilms in combination with linezolid

Methods: The susceptibility of biofilm cultures of three S. aureus strains to Methylene Blue [MB] and Toluidine Blue O [TBO]-mediated PDI was determined alone and in combination with linezolid

Results: Bactericidal activity [>/=3 log[10] reduction in viable cell count] was not achieved with MB/TBO-PDI or antibiotic treatment alone. When antibiotic treatment was combined with TBO-PDI, a greater reduction in viable count than antibiotic alone was observed for two strains

Conclusion: This study showed that although TBO-PDI did not have good bactericidal activity against S. aureus biofilms; it increased the antimicrobial activity of linezolid against these bacteria

Prevalence of mood disorders in Iran

To study the prevalence and demographic characteristics of mood disorders among Iranian adults. In this cross-sectional population-based epidemiological study [age 18] in Iran, 25180 individuals were selected through a randomized cluster sampling method for a diagnosis using the Schedule for Affective Disorders and Schizophrenia [SADS]. They were then interviewed at home by 250 trained clinical psychologists. The estimated lifetime prevalence of Major Depressive Disorder [MOD] and Minor Depressive Disorder [mDD] were 3.1% and 0.3% respectively. Also, the estimated lifetime prevalence of Bipolar Mood disorder [BMD] type I and type II were 0.1% and 0.7% respectively. The current prevalence of MDD, mDD, BMD-I and BMD-II were 1.8%. 0.2%, 0.04%, and 0.3% respectively. Mood disorders were associated with female gender, lower education, being married, being middle-aged, living in cities, and not being a homemaker. The prevalence of mood disorders was lower among Iranian adults than reported in Western studies, and a number of demographic associations differed from those reported in Western studies: Important cultural differences in the nature or manifestation of depression are implied by these results