ABSTRACT
Background: Klebsiella pneumoniae [K. pneumoniae] is an opportunistic pathogen that could be resistant to many antimicrobial agents. Resistance genes can be carried among gram-negative bacteria by integrons. Enzymatic inactivation is the most important mechanism of resistance to aminoglycosides. In this study, the frequencies of two important resistance gene aac[6']-IIa and ant[2'']-I, and genes coding integrase I and II, in K. pneumonia isolates resistant to aminoglycosides were evaluated
Methods: In this cross-sectional study, an attempt was made to assess the antibiotic susceptibility of 130 K. pneumonia isolates obtained from different samples of patients hospitalized in training hospitals of Yazd evaluated by disk diffusion method. The frequencies of aac[6']-IIa, ant[2'']-I, intl1, and intl2 genes were determined by PCR method. Data were analyzed by chi-square method using SPSS software [Ver. 16]
Results: our results showed that resistance to gentamicin, tobramycin, kanamycin, and amikacin were 34.6, 33.8, 43.8, and 14.6%, respectively. The frequencies of aac[6']-IIa, ant[2'']-I, intl1, and intl2 genes were 44.6, 27.7, 90, and 0%, respectively
Conclusion: This study showed there are high frequencies of genes coding aminoglycosides resistance in K. pneumonia isolates. Hence, it is very important to monitor and inhibit the spread of antibiotic resistance genes
ABSTRACT
Statement of the Problem: Orthodontic appliances facilitate microbial plaque accumulation and increase the chance of white spot lesions. There is a need for new plaque control methods independent of patient's cooperation
Purpose: The aim of this study was to determine the effects of incorporating copper oxide [CuO] nanoparticles on antimicrobial properties and bond strength of orthodontic adhesive
Materials and Method: CuO nanoparticles were added to the composite transbond XT at concentrations of 0.01, 0.5 and 1 wt.%. To evaluate the antimicrobial properties of composites containing nanoparticles, the disk agar diffusion test was used. For this purpose, 10 discs from each concentration of nano-composites [totally 30 discs] and 10 discs from conventional composite [as the control group] were prepared. Then the diameter of streptococcus mutans growth inhibition around each disc was determined in blood agar medium. To evaluate the shear bond strength, with each concentration of nano-composites as well as the control group [conventional composite], 10 metal brackets were bonded to the human premolars and shear bond strength was determined using a universal testing machine
Results: Nano-composites in all three concentrations showed significant antimicrobial effect compared to the control group [p< 0.001]. With increasing concentration of nanoparticles, antimicrobial effect showed an upward trend, although statistically was not significant. There was no significant difference between the shear bond strength of nano-composites compared to control group [p= 0.695]
Conclusion: Incorporating CuO nanoparticles into adhesive in all three studied concentrations added antimicrobial effects to the adhesive with no adverse effects on shear bond strength
ABSTRACT
Statement of the Problem: Fixed orthodontic appliances predispose patients to dental caries. Use of mouthrinses has been introduced as the effective way for reducing dental plaque accumulation
Purpose: The aim of this study was to compare the effects of Persica mouthwash and Chlorhexidine [CHX] on colonization of Streptococcus mutans [S. mutans] on fixed orthodontic O-rings
Materials and Method: Thirty patients with fixed orthodontic appliances and proper oral hygiene were randomly provided by CHX and Persica and trained to use these mouthwashes according to the manufacturer's instruction. Sampling was carried out right before and 4 weeks after mouthrinsing treatment. The mean amounts of S. mutans colonies in these groups were compared
Results: Comparison of S. mutans colonization within each group revealed both mouthrinses to be efficient. However, this difference was found to be significant only in CHX group
Conclusion: Persica cannot be a good alternative mouthwash and patients on orthodontic treatment are still recommended to use CHX
ABSTRACT
The milks expressed from the mothers' breast might be infected during squeeze, storage and/or transmission. The infection level has been reported as different in various studies up to 97 percent. The main purpose of this study is to determine the infection level and its relevant organisms as well as to specify drug allergy of the expressed milks from the mothers with their infant admitted to NICU ward. In this study, among the expressed milks from 80 mothers, were cultured each in an amount of 0.5-1cc and antibiotic discs selected for every strain was placed. The results indicate that 85 percent of samples were infected and dominant microorganisms were firstly Klebsiella [13.7%] and then S. epidermidis [12.5%]. In addition, 95% of Gram negative bacteria strains were susceptible to imipenem. The most effective antibiotic on isolated staphylococci was ceftizoxime [46.6% resistance]. The colony count in 32.4% gram negative bacteria and in 66.7% gram positive bacteria was between 10[4] to 10[5]CFU/ml and the remaining was above 10[5]CFU/ml [p=0.02]. Furthermore, there was no significant relationship between bacterial infection of the expressed milks with the site of milk expressing [house or hospital], mode of expressing[by pump or hand], storage duration and the mother's demographic characteristics including age and/or literacy. The studies show that infection prevalence in the milk samples was 85%; the most common infection factor was Klebsiella and then S. epidermidis that is indicative of high prevalence of hospital infection [nosocomial infection] in the infants ward