The Study of Synergistic Effects of n.butanolic Cyclamen coum Extract and Ciprofloxacin on inhibition of Pseudomonas aeruginosa biofilm formation

  Introduction : Infections caused by Pseudomonas aeruginosa biofilm are the major causes of death in patients with cystic fibrosis (CF). Some studies revealed that biofilms are resistant to several antibiotics because of their impermeable structures. In order to re-sensitize bacteria to different antibiotics, biofilm formation should be inhibited. In this research, evaluation of antibiofilm activity of n-butanolic Cyclamen coum extract as a medici­nal plant from Myrsinaceae family, in combination with ciprofloxacin was carried out.   Materials and method s: The biofilm formation ability by P. aeruginosa PAO1 and one clinically isolated P. aeruginosa (PA214) was confirmed by microtiter plate method. Extraction of the tubers of Cyclamen coum was done by fractionation method . The antibiofilm and antibacterial properties of n-butanolic C. coum extract (which includes saponin compounds) alone and in combination with ciprofloxacin by using microdilution and crystal violet methods were examined. The cytotoxicity effect of the n-butanolic extract on HT-29 cells was assayed by MTT (3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl-tetrazolium bromide) test.   Results : The biofilm formation ability by P. aeruginosa strains was quantitatively confirmed. Saponin content of the n-butanolic C.coum extract was 156 µg/mL. The extract revealed antibacterial activity against the growth of planktonic P. aeruginosa strains. The combination of n-butanolic C.coum extract and ciprofloxacin significantly inhibited P.aeruginosa biofilm formation (ΣFBIC = 0.5). The n-butanolic C.coum extract showed insignificant cytotoxic effect against HT-29 human cancer cell line after 48 hours and 72 hours incubation .   Discussion and conclusion : It can be concluded that n-butanolic C.coum extract in combination with ciprofloxacin significantly revealed antibiofilm activity against P. aeruginosa biofilm however, further clinical investigations are required

Molecular Typing of Klebsiella pneumoniae isolates using Repetitive Extragenic Palindromic Sequence-Based PCR in a Hospital in Tehran, Iran

Background: The presence of extended-spectrum β-lactamases (ESBLs) is increasing worldwide and blaCTX-M1 is the predominant β-lactamase. Objective: This study was conducted to determine the ESBL production and prevalence of blaCTX-M1, blaSHV and blaTEM and AmpC genes and repetitive extragenic palindromic polymerase chain reaction (rep-PCR) pattern among Klebsiella pneumoniae isolates in Tehran from 2014 to 2016. Materials and Methods: One hundred eleven isolates were collected during the study period. The PCR was employed to detect the blaCTX-M1, blaSHV, blaTEM and AmpC genes. The genetic relation of isolates was performed using rep-PCR typing method. Results: Eighty-three and 86 isolates showed Minimum inhibitory concentration (MIC) ≥2 against ceftazidime and cefotaxime, respectively and 80 (72%) isolates exhibited ESBL production. The prevalence of blaCTX-M1, blaSHV, blaTEM and AmpC genes among ESBL producers was 92.5% (n = 74), 66.2% (n = 53), 56.2% (n = 45) and 2.5% (n = 2), respectively. The rep-PCR typing pattern of isolates showed a wide diversity, indicating the polyclonal spread of CTX-M type producing isolates. Conclusion: The findings of this study highlighted the emergence and spread of K. pneumoniae isolates producing CTX-M and other ESBL enzymes with diverse genetic backgrounds in a hospital in Tehran

Electrosprayed cefazolin‐loaded niosomes onto electrospun chitosan nanofibrous membrane for wound healing applications

Chronic wounds are among the most therapeutically challenging conditions, which are commonly followed by bacterial infection. The ideal approach to treat such injuries are synergistic infection therapy and skin tissue regeneration. In the recent decades, nanotechnology has played a critical role in eradicating bacterial infections by introducing several carriers developed for drug delivery. Moreover, advances in tissue engineering have resulted in new drug delivery systems that can improve the skin regeneration rate and quality. In this study, cefazolin-loaded niosomes were electrosprayed onto chitosan membrane for wound healing applications. For this purpose, niosomes were obtained by the thin-film hydration method; electrospinning was then conducted to fabricate nanofibrous mats. In vitro characterization of the scaffold was performed to evaluate the physicochemical and biological properties. Finally, in vivo studies were carried out to evaluate the potential use of the membrane for skin regeneration. In vitro results indicated the antibacterial properties of the membrane against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) due to the gradual release of cefazolin from niosomes. The scaffolds also showed no cell toxicity. In vivo studies also confirmed the ability of the membrane to enhance skin regeneration by improving re-epithelialization, tissue remodeling, and angiogenesis. The current study could well show the promising role of the prepared scaffold for skin regeneration and bacterial infection elimination