No abstract

Emergence of vancomycin-intermediate Staphylococcus aureus (VISA) and vancomycin-resistant S. aureus (VRSA) strains has led to global concerns about treatments for staphylococcal infections. These strains are currently rare even though there is an upward trend in their reported incidence. Therefore, appropriate screening and epidemiological evaluation of VRSA strains can affect future global health care policies. Isolates of Staphylococcus aureus were obtained from various clinical samples and were then evaluated with agar screening, disk diffusion, and MIC methods to determine resistance to vancomycin and methicillin. After confirmation of the isolated VRSA strain, genetic analysis was performed by evaluating mecA and vanA gene presence, SCCmec, agr, and spa types, and toxin profiles. Multilocus sequence typing (MLST) and plasmid analysis were also performed. The VRSA strain was resistant to oxacillin (MIC of 128 g/ml) and vancomycin (MIC of 512 g/ml). Disk diffusion antimicrobial susceptibility tests showed resistance to oxacillin, vancomycin, levofloxacin, ciprofloxacin, trimethoprim-sulfamethoxazole, clindamycin, rifampin, and tetracycline. The isolate was susceptible to minocycline and gentamicin. PCRs were positive for the mecA and vanA genes. Other genetic characteristics include SCCmec type III, agr I, spa type t037, and sequence type (ST) 1283. The plasmid profile shows five plasmids with a size of ϳ1.7 kb to >10 kb. The isolated VRSA strain was obtained from a critically ill hospitalized patient. Genetic analysis of this strain suggested that the strain was a methicillin-resistant S. aureus (MRSA) clone endemic in Asia that underwent some genetic changes, such as mutation in the gmk gene and acquisition of the vanA gene.

The purpose of this study was to evaluate the efficacy of Ca(OH)2 with or without a silver nanoparticle suspension to eliminate Enterococcus faecalis from root canals. A total of 66 extracted human single-rooted teeth contaminated with E. faecalis were treated with 10% Ca(OH)2 alone, Ca(OH)2 with nanosilver or sterile water (as a negative control). Samples were obtained with paper points and Gates-Glidden burs at 1 and 7 days after root canal preparation and the number of colony-forming units (CFU) was determined. The number of CFUs observed after dressing with Ca(OH)2  + nanosilver was significantly less than the number observed with Ca(OH)2 alone after 1 or 7 days (P < 0.001, P < 0.001). No differences in antimicrobial properties were observed between the two time points in the Ca(OH)2  + nanosilver group (P > 0.05). Higher antimicrobial efficacy was observed in the Ca(OH)2 group after 7 days than 1 day (P < 0.001). This study highlighted the potential advantage of using a mixture of Ca(OH)2 and nanosilver for intracanal medicament.

Numerous studies have demonstrated that targeting immunogens to FcγR on antigen-presenting cells (APCs) can selectively uptake and increase cellular immunity in vitro and in vivo. Therefore, the present study was conducted to evaluate immunogenicity of a novel multistage tuberculosis vaccine, a combination of an early and a dormant immunogenic protein, ESAT6 and HspX, fused to Fcγ2a fragment of mouse IgG2a to target all forms of tuberculosis. Codon-optimized genes consisting of ESAT6, a linker, and HspX fused either to mouse Fcγ2a (ESAT6:HspX:mFcγ2a) or 6× His-tag (ESAT6:HspX:His) were synthesized. The resulting proteins were then produced in Pichia pastoris. The fusion proteins were separately emulsified in dimethyldioctadecylammonium bromide(DDA)-trehalose-6,6-dibehenate(TDB) adjuvant, and their immunogenicity with and without bacille Calmette-Guérin (BCG) was assessed in C57BL/6 mice. Th1, Th2, Th17, and T-reg cytokine patterns were evaluated using the ELISA method. Both multistage vaccines induced very strong IL-12 and IFN-γ secretion from splenic cells; the Fc-tagged subunit vaccine induced a more effective Th1 immune response (IFN-γ, 910 pg/mL, and IL-12, 854 pg/mL) with a very low increase in IL-17 (∼0.1 pg/mL) and IL-4 (37 pg/mL) and a mild increase in TGF-β (543 pg/mL) compared to the BCG or ESAT6:HspX:His primed and boosted groups. The production of IFN-γ to ESAT6:HspX:Fcγ2a was very consistent and showed an increasing trend for IL-12 compared to the BCG or ESAT6:HspX:His primed and boosted groups. Fcγ2a used as a delivery vehicle supported the idea of selective uptake, inducing cross-presentation and forming a proper anti-tuberculosis response in context of Th1/Th2 and Th17/T-reg balances, which is important for protection and prevention of damage.

This study did not show relationship between HPV and leukoplakia. Although no statistically significant relationship was found between HPV and VC, but considering sample size limitation for such uncommon cases, its presence in three cases of 14 makes more investigations to overcome the controversies necessary.