Anti protein A antibody-gold nanorods conjugate: a targeting agent for selective killing of methicillin resistant Staphylococcus aureus using photothermal therapy method.

The high prevalence of methicillin resistant Staphylococcus aureus (MRSA) and developing resistance to antibiotics requires new approaches for treatment of infectious diseases due to this bacterium. In this study, we developed a targeting agent for selective killing of MRSA using photothermal therapy method based on anti protein A antibody and gold nanorods (GNRs). Polystyrene sulfonate (PSS) coated GNRs were conjugated with anti protein A antibody. The FT-IR and UV-vis analyses approved the formation of anti protein A antibody-gold nanorods conjugate. In vitro study of photothermal therapy showed 82% reduction in the MRSA cells viability which was significantly greater than the ablation effect of free GNRs and laser alone. Significant accumulation of anti protein A antibody-GNRs in the infected muscle in comparison with normal muscle approved the targeting ability of new agent. In vivo study of photothermal therapy resulted in a significant reduction (73%) in the bacterial cells viability in the infected mouse model. These results demonstrated the ability of anti protein A antibody-GNRs conjugate in combination with NIR laser energy for selective killing of MRSA in mouse model.

Hepatitis B surface antigen prevalence in pregnant women: A cross-sectional survey in Iran.

BACKGROUND: Vertical transmission of hepatitis B virus (HBV) from infected mothers to their neonates is one of the most important routes of infection. The exact prevalence rate of HBV in Iranian pregnant mothers is not well known but based on different studies it is estimated between 0.35% and 6.5%. The aim of this study was to determine the seroprevalence of hepatitis B surface antigen (HBsAg) in pregnant women of selected provinces in Iran. METHODS: At this cross-sectional study, seven provinces supposed to be of high and low prevalence of hepatitis B in the general population selected. Multistage sampling was used to enroll 5261 parturient women who attended the target provinces birth facilities, during January to March of 2011, were recruited to study. To determine the statistically significant mean and proportion differences, t-test and χ (2) test were used, respectively. RESULTS: Overall 1.2% was positive HBsAg of which 11% of them were hepatitis B e-antigen positive as well. The eastern and north eastern provinces were considerably higher in HBsAg seropositivity than the west and northwest of the country. CONCLUSIONS: In view of the considerable prevalence of hepatitis B in pregnant women, screening all pregnant women prioritizing the eastern and north-eastern provinces is strongly recommended.