ABSTRACT
BACKGROUND: Burkholderia cepacia adhesion and biofilm formation onto abiotic surfaces is an important feature of clinically relevant isolates. The in vitro biofilm formation of B. cepacia onto coated indwelling urinary catheters (IDCs) with moxifloxacin has not been previously investigated. OBJECTIVES: To examine the ability of B. cepacia to form biofilms on IDCs and the effect of coating IDCs with moxifloxacin on biofilm formation by B. cepacia in vitro. MATERIAL AND METHODS: The adhesion of B. cepacia to coated and uncoated IDCs with moxifloxacin was evaluated. Pieces of IDCs were coated with moxifloxacin (adsorption method). The spectrophotometric method was used to check moxifloxacin leaching into tubes. Coated and uncoated tubes were incubated with 107 colony forming units (cfu)/mL of B. cepacia. The viable bacterial count was used to count the number of bacteria adhered to coated and uncoated IDC pieces. RESULTS: A significant adhesion of B. cepacia to uncoated IDC pieces started 15 min after the incubation in a bacterial suspension (107 cfu/mL). A maximum adhesion was observed at 48 h. The pretreatment of IDCs with 100 µg/mL of moxifloxacin produced the best adsorption of antibiotic onto the IDCs. Coating IDC pieces with moxifloxacin significantly reduced the adhesion and biofilm formation of B. cepacia (p < 0.05) at various time intervals (1 h, 4 h and 24 h). CONCLUSIONS: The present study has demonstrated for the first time that coated IDCs with moxifloxacin reduce B. cepacia adhesion and biofilm formation. This finding has opened the door to the production of the new generation IDCs that prevent bacteria from attaching and forming biofilms.
Subject(s)
Burkholderia cepacia , Biofilms , Catheters, Indwelling , Moxifloxacin/pharmacology , Urinary Catheterization , Urinary CathetersABSTRACT
Stenotrophomonas maltophilia is an important opportunistic pathogen that affects immunocompromised individuals. Viable bacterial count method was used to count the number of adhered bacteria. The current study showed the efficiency of S. maltophilia (Sm2) adhesion on different parts of mouse intestinal tract (IT), small intestinal tract (SIT), large intestinal tract (LIT) and rectum (P<0.05) and this ability was equal for each part of IT [ANOVA test (P > 0.05)]. Moxifloxacin (0.03 x MIC) resulted a significant decrease in adhesion of S. maltophilia to SIT (P<0.05) versus control and other sub-inhibitory moxifloxacin concentrations (0.06 x and 1.2 x MIC). It can be concluded from the current study that the S. maltophilia (Sm2) has a good ability to adhere to mouse IT and the lowest concentrations of moxifloxacin (0.03 x MIC) reduced the ability of this bacterium to infect IT by reducing the ability of this bacterium to adhere to IT.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Adhesion/drug effects , Gram-Negative Bacterial Infections/drug therapy , Intestines/drug effects , Moxifloxacin/pharmacology , Stenotrophomonas maltophilia/immunology , Animals , Disease Models, Animal , Gram-Negative Bacterial Infections/microbiology , Intestines/microbiology , Kinetics , Male , Mice, Inbred BALB C , Microbial Sensitivity Tests , Microbial Viability/drug effectsABSTRACT
Chronic hepatitis B involves different immune cells. The direct role of antibody-secreting B cells in the severity of chronic hepatitis B unclear. In this study, the number of plaque forming cells [PFC-(IgG, IgM, anti-HBc IgG, and anti-HBc IgM)], liver function tests (LFT) [alkaline phosphatase (ALP), alanine aminotransferase (ALT), and total serum bilirubin (TSB)], the levels of IL-10 in sera and in lymphocyte cultures, the number of CD4(+) and CD8(+) cells were measured in the peripheral blood of patients and in the controls. In addition, the hepatocytotoxic effect of anti-HBc and anti-HBe in vitro was studied. The largest number of PFCs was observed in the peripheral blood of patients with chronic hepatitis B. This was concomitant with a decrease in CD4(+) /CD8(+) ratio versus this ratio in asymptomatic HBV carriers and in healthy volunteers (P < 0.05). An increase in immunoglobulin (IgG and IgM) levels, anti-HBc IgG, and anti-HBc IgM levels and LFTs in peripheral blood of patients with chronic hepatitis B was seen. Anti-HBc induced hepatocytotoxicity in vitro. The expression of mRNA and protein for IL-10 production was observed at a significant level in culture of lymphocytes isolated from patients with chronic hepatitis B. In addition, a high level of IL-10 was found only in the sera of patients with chronic hepatitis B. It is concluded that the antibody-secreting B cells and the antibodies, which are produced, play an important role in the severity of chronic hepatitis B, which was related negatively with CD4(+) /CD8(+) ratio and positively with IL-10 expression.
