Antibiotic resistance pattern and distribution of psla gene among biofilm producing pseudomonas aeruginosa isolated from waste water of a burn center

Background: Pseudomonas aeruginosa is considered as a major cause of hospital-acquired infections due to its high antibacterial resistance. Biofilm formation is a well-known pathogenic mechanism in P. aeruginosa infections, since sessile bacteria are protected in an extracellular matrix of exopolysaccharide. The expression of polysaccharide synthesis locus (pslA gene) can be important for biofilm formation by P. aeruginosa. Objectives: The purpose of this research was to evaluate the antibiotic resistance pattern and distribution of the pslA gene among biofilm-producing P. aeruginosa isolates obtained from waste water of Burn Centre in Guilan, Iran. Materials and Methods: Fifty isolates of P. aeruginosa were obtained from waste water of a burn center. The P. aeruginosa isolates were identified using standard bacteriological procedures. Drug susceptibility test was performed by disk diffusion method for all the isolates against nine antimicrobial agents. Biofilm formation was measured by microtiter plate assay. Polymerase chain reaction (PCR) was used to identify the presence of the pslA gene among the isolates. Results: Biofilm formation was observed in 70 of the P. aeruginosa isolates. The potential formation of biofilm was significantly associated with resistance to gentamicin, imipenem, tobramycin and piperacillin. In addition, the pslA gene only existed in biofilm-producing isolates with a frequency of 42.9 (n = 15).Conclusions: The findings of the present study well demonstrated that the P. aeruginosa biofilm-producing isolates were more resistant to the tested antibiotics. Furthermore, because of wide distribution, it seems that the pslA gene is associated with biofilm formation. � 2015, Ahvaz Jundishapur University of Medical Sciences

Study of CAPE effect on apoptosis induction in AGS human gastric cancer cell line

Background: Propolis is a natural product of bee and caffeic acid phenethyl ester (CAPE) is a pharmacologically important product of propolis. Objectives: The aim of this study was to investigate the effect of CAPE on apoptosis induction in AGS human gastric cancer cells. Materials and Methods: The cytotoxic effects of CAPE at different concentrations were investigated on AGS cells viability after 24 hours treatment by MTT assay. To measure the effect of CAPE on apoptosis induction, AGS cells were treated with CAPE for 24 hours and investigated by FITC Annexin V/PI staining using flow cytometry. Results: CAPE prevented growth and proliferation of AGS human gastric cancer cell line in a concentration-dependent manner with an IC50 of approximately 60 μM by a 24-hour treatment. Also CAPE caused increased induction of apoptosis in AGS cells from 1.37 % in control cells to 21.76 % in treated cells with 30 μM CAPE. Conclusions: CAPE prevents growth and proliferation of AGS human gastric cancer cell line through inducing programmed cell death in AGS cells. Therefore, CAPE could be helpful for developing chemotherapeutic agents or as an adjuvant for human gastric cancer treatment. © 2016, School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences

Role of Wnt signaling on proliferation of menstrual blood derived stem cells

Aim: Menstrual blood derived stem cells (MenSCs) are unique stem cells that have been isolated and identified recently. The special traits of MenSCs can be related to the cell signaling pathways. In this study, in order to find out the role of Wnt signaling on MenSCs proliferation, we evaluated ß-catenin expression as a key participant in Wnt signaling pathway in response to Lithium chloride (LiCl). Methods: MenSCs were isolated from healthy women by combining gradient density centrifugation with plastic adherence. After characterization of the isolated cells, cell proliferation of MenSCs in presence of 10-15 mM LiCl was evaluated by MTT assay. ß-catenin expression of the treated cells was examined using immunofluorescence technique. Results: Flow cytometric analysis revealed that both mesenchymal and embryonic stem cell markers are expressed on menstrual blood stem cells. MTT value decreased depending on the LiCl concentration. The proliferation of MenSCs cultivated in culture media containing 15mM LiCl was approximately two fold less than those grown without LiCl (p<0.01). Moreover, nuclear accumulation of ß-catenin protein in cells treated by LiCl was greater than cells without LiCl. Conclusion: The MenSCs are stem cell populations with high proliferation ability and unique immunophenotyping properties. Our results demonstrated that Wnt signaling pathway regulates MenSCs proliferation via trans-localization of activated-ß-catenin protein

Study on antibacterial activity of newly synthesized derivatives of pyranopyrazole, pyrazolo[1,2-b]phtalazine and bis-pyrazole

&lt;p&gt;In recent years, due to a sharp increase of antibiotic resistance, synthesized derivative compounds have been considered as a superseded source for new drugs. With regard to the high therapeutic behavior of isatin derivatives from many aspects of drug discovery, in this study, the antibacterial effects of newly synthesized derivatives of pyranopyrazole, pyrazolo[1,2-b]phtalazine and bis-pyrazole against Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis were examined.&lt;/p&gt;&lt;p&gt;Twelve individual compounds were weighted and prepared at a final concentration of 1 mg/mL in dimethyl sulfoxide (DMSO). Bacterial test organisms were maintained in nutrient agar slants at 4ºC and subcultured in Petri plates prior to use. The tested compounds are randomly added into the wells with a 100 μl volume on the plate under sterile condition and then were incubated at 37ºC for 24 hours. All experiments were repeated three times and the mean values are reported as the results. The antibacterial effects of the compounds that produced ≥ 8mm zone of inhibition were tested quantitatively by Micro broth dilution method for determination of minimal inhibitory concentration (MIC) value. After incubation overnight, the first tube with clean appearance determined the MIC.&lt;/p&gt;&lt;p&gt;According to the results, the MIC of the compounds defined as c and d against S. aureus is 64 (μg/ml). It is found that the synthesized compounds are only effective against S. aureus.&lt;/p&gt;&lt;p&gt;The comparison of the maximum zone of inhibition (22±0.4) and MICs between the present study and those in literature, shows the privilege of using compound c and d against S. aureus.&lt;/p&gt