Antibacterial and anticancer activity of a bioflavonoid fractionated from Allium Ascalonicum

Allium ascalonicum is a part of the diet of many populations of the world due to their long-held beliefs. A. ascalonicum extracts have been reported have antibacterial properties and prevent cancer cell proliferation. This study was conducted for the purpse of evaluating the anticancer and antibacterial activity of a flavonoid fraction isolated from A. ascalonicum bulbs.  The HeLa and HUVEC cells were used as target cell line and some gram negative and positive bacteria were also targeted for antimicrobial activity. The A. ascalonicum plant was collected from the Zagros Mountains in the north of Dezful city- Iran, in September 2016 and confirmed by School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran. The water extract of bulbs of this plant was extracted and the flavonoid fraction was isolated from aquous extract by ethyl acetate. The antibacterial and anticancer effects of isolated falavonoid were determined using MIC and MTT respectively. The best antibacterial effect of falvonoid extracted from A.ascalonicum was found against C. diphtheria. Furthermore, gentamicin resistant P.aeruginosa was the most resistant pathogenic bacterium. The MTT method showed that this fraction had a concentration-dependent anti-proliferative activity on HeLa cell lines and there was no cytotoxic effect against HUVEC cells.      The inhibitory concentration 50% (IC50) values of the A. ascalonicum extract for Hela cell was 3 mg/mL but the treatment of HUVECs with the A. ascalonicum showed no considerable effect. The flavonoid fraction of A.ascalonicum bulbs had remarkable antibacterial and anticancer properties. Therefore, it could be used as an antibacterial and anticancer agent for control of cancers and infectious diseases.

Prevalence of drug-resistant <i>Pseudomonas aeruginosa</i> in Iranian burned patients: A meta-analysis

The increasing prevalence of drug-resistant Pseudomonas aeruginosa in burned patients is one of the main public health problems worldwide. Although drug-resistant P. aeruginosa in burn units is frequent in some countries and unusual in others, the level of this conditions is not precisely known in Iran. Imipenem is one of the most potent agents against P. aeruginosa. Imipenem resistance is a major obstacle to treatment of P. aeruginosa infections. We aimed to determine the true prevalence of imipenem-resistant P. aeruginosa in Iranian burned patients according to the Preferred Reporting Items for Meta-Analyses statement. Moreover, resistance to several potent anti-P. aerugi nosa drugs were indicated according to the Clinical and Laboratory Standards Institute guidelines for the disc diffusion method. Several databases including Web of Science, Scopus, PubMed, Scientific Information Database, Magiran, Iranmedex, and science direct were searched to get studies addressing drug-resistant P. aeruginosa in Iranian burned patients from March 2006 to May 2015. A total of 34 reports available from different areas of Iran were included in the current study. The meta-analyses showed that 54.9 of P. aeruginosa were resistant to imipenem. The most common resistance was seen against ceftazidime (66.9), followed by ciprofloxacin (52.9) and cefepime (52.3). It is necessary to know the epidemiology of drug-resistant P. aeruginosa because it can promote control strategies for decreasing their prevalence. The high incidence of drug-resistant P. aeruginosa in Iran emphasizes the need for precise drug susceptibility testing, continuous monitoring of drug resistance, especially in burn units, use of sensitive methods for the laboratory diagnosis, and close relation between physician and laboratories

The antibacterial activity of Iranian plants extracts against metallo beta-lactamase producing Pseudomonas aeruginosa strains

Metallo β-lactamases (MBLs) producing Pseudomonas aeruginosa (P. aeruginosa) isolates are becoming an escalating global threat. Among the antibiotics used to treat infections associated with P. aeruginosa, resistance to carbapenem is a serious therapeutic challenge. The aim of the present study was to detect MBL-producing P. aeruginosa and to evaluate the extracts of Urtica. dioica, Carum. copticum, and Zataria multiflora on these clinical pathogens. The study was performed on hospitalized burn patients during 2014. Antibiotic susceptibility testing was tested by broth micro dilution and disc diffusion methods. The MBLs were detected using combination disk diffusion test (CDDT) phenotypically. Then, PCR and sequencing methods were carried out to detect the MBL encoding genes. Among 83 imipenem resistant P. aeruginosa strains, 48 (57.9%) isolates were MBL-producing P. aeruginosa. PCR and sequencing methods confirmed that these strains were blaIMP-1positive genes, whereas none were positive for blaVIM genes. Hospitalized burn patients with MBL-producing P.aeruginosa infection had 4/48 (8.3%) mortality rate. It was demonstrated that C. copticum, U. dioica, and Z. multiflora extracts had significant antibacterial effects on regular and IMP-producing P. aeruginosa strains. The prevalence of MBL-producing P .aeruginosa isolates in burn patients is very high. In this study, all MBL-producing strains encode the blaIMP-1gene. Therefore, detection of MBL-producing strains has major importance in identifying drug resistance patterns in P. aeruginosa and in controlling of infections. In the current study, the extracts from C. copticum, U. dioica, and Z. multiflora had high antibacterial effects against β-lactamase producing P. aeruginosa isolates.

Detection of acrA, acrB, aac(6′)-Ib-cr, and qepA genes among clinical isolates of Escherichia coli and Klebsiella pneumoniae

Background: The distribution of drug resistance among clinical isolates of Escherichia coli and Klebsiella pneumoniae has limited the therapeutic options. The aim of this study was to report the prevalence of quinolone resistance genes among E. coli and K. pneumoniae clinical strains isolated from three educational hospitals of Tehran, Iran. Materials and methods: A total of 100 strains of E. coli from Labbafinejad and Taleghani Hospitals and 100 strains of K. pneumoniae from Mofid Children and Taleghani Hospitals were collected between January 2013 and May 2014. Antimicrobial susceptibility tests were done by disk diffusion method based on Clinical and Laboratory Standards Institute guidelines. Detection of qepA, aac(6′)-Ib-cr, acrA, and acrB genes was done by polymerase chain reaction (PCR). Results: In this study, fosfomycin and imipenem against E. coli and fosfomycin and tigecycline against K. pneumoniae had the best effect in antimicrobial susceptibility tests. PCR assay using specific primers demonstrated that the prevalence of qepA, aac(6′)-Ib-cr, acrA, and acrB genes among the 100 E. coli isolates was 0 (0%), 87 (87%), 92 (92%), and 84 (84%), respectively. The prevalence of qepA, aac(6′)-Ib-cr, acrA, and acrB genes among the 100 K. pneumoniae isolates was 4 (4%), 85 (85%), 94 (94%), and 87 (87%), respectively. Conclusion: The distribution of qepA, aac(6′)-Ib-cr, acrA, and acrB resistance determinants in E. coli and K. pneumoniae is a great concern. Therefore, infection control and prevention of spread of drug-resistant bacteria need careful management of medication and identification of resistant isolates

Emergence of fosfomycin resistance among isolates of Escherichia coli harboring extended-spectrum and AmpC β-lactamases

Urinary tract infection (UTI) is a common type of infectious disease globally. The aim of this study was to detect the frequency of fosA3 and fosC2 genes in extended-spectrum β-lactamases (ESBL) and blaDHA, blaCMY-2, and blaCMY-42 genes in AmpC β-lactamases-producing isolates of Escherichia coli. In total, 120 isolates of E. coli were collected from three teaching hospitals between March 2014 and February 2015. Antibiotic susceptibility tests were carried out by disk diffusion method. The presence of blaCMY-2, blaCMY-42, blaDHA, fosA3, and fosC2 genes was detected by polymerase chain reaction (PCR) and sequencing. Of the 120 strains, 92 (76.6%) were identified as ESBL producers, 30 (25%) were determined as AmpC β-lactamase producers, and 24 (20%) had both ESBL and AmpC β-lactamase enzymes. Imipenem, fosfomycin, and nitrofurantoin had the best effect against isolates of E. coli. PCR assay demonstrated that the frequency of blaCMY-2, blaCMY-42, and blaDHA genes among AmpC β-lactamases-producing strains were 39%, 1%, and 17.5%, respectively. This study reports the first detection of fosfomycin resistance in Iran. This study indicated the increasing prevalence of UTI isolates of E. coli-harboring ESBL and AmpC β-lactamases genes in Iran. Therefore, due to the high rate of blaDHA and blaCMY genes and emergence of fosfomycin-resistant E. coli isolates, we recommend continuous monitoring of antibiotic resistance as well as attention to guidelines of infection controls

Clonal dissemination of Staphylococcus aureus isolates causing nosocomial infections, Tehran, Iran

Objective(s): In the current research, the prevalence of Staphylococcus aureus clones and genes encoding antimicrobial resistance and toxins were examined among 120 S. aureus strains from nosocomial infections in tehran, Iran.Materials and Methods: Antimicrobial susceptibility was examined, based on disk diffusion and PCR method to identify resistance and toxin-encoding genes. Based on the polymorphisms in SCCmec, agr, spa, and MLST, the isolates were typed. Results: Among 120 S. aureus isolates, 85 (70.8%) were  methicilin resistant S. aureus (MRSA), and 35 (29.2%) were methicilin sensetive S. aureus (MSSA). The tested isolates contained resistance genes, including ant(4΄)-Ia (90%), aac(6΄)-Ie/aph(2˝) (80%), aph(3΄)-IIIa (30%), erm(A) (26.7%), erm(B) (10.8%), erm(C) (11.7%), msr(A) (40.8%), msr(B) (14.2%), tet(M) (45.8%), and mupA (8.3%). The MRSA strains were clustered into six different clones. The most common genotypes included ST239-SCCmec III/t037 (23.3%), ST239-SCCmec III/t388 (22.5%), ST22-SCCmec IV/t790 (8.3%), ST15-SCCmec IV/t084 (7.5%), ST585-SCCmec III/t713 (5%), and ST239-SCCmec III/t924 (4.2%), respectively. ST182/t196 (8.3%) and ST123/t171 (5%) belonged exclusively to MSSA strains. Overall, 10 (66.7%) and 5 (33.3%) out of 15 isolates with pvl genes were attributed to clones ST22-SCCmec IV/t790 and ST15-SCCmec IV/t084, respectively. ST22-SCCmec IV/t790, ST239-SCCmec III/t037, and ST15-SCCmec IV/t084, were related to high-level mupirocin-resistant phenotypes.  Conclusion: The genetic diversity of S. aureus was confirmed in our hospitals, and ST239-SCCmec III/t037 showed a relatively high prevalence in our study. It seems that assessment of resistance and virulence genes in different S. aureus molecular types is necessary for proper antibiotic consumption

Evaluation of Brucellosis Vaccines: A Comprehensive Review

Brucellosis is a bacterial zoonosis caused by Brucella spp. which can lead to heavy economic losses and severe human diseases. Thus, controlling brucellosis is very important. Due to humans easily gaining brucellosis from animals, animal brucellosis control programs can help the eradication of human brucellosis. There are two popular vaccines against animal brucellosis. Live attenuated Brucella abortus strain 19 (S19 vaccine) is the first effective and most extensively used vaccine for the prevention of brucellosis in cattle. Live attenuated Brucella melitensis strain Rev.1 (Rev.1 vaccine) is the most effective vaccine against caprine and ovine brucellosis. Although these two vaccines provide good immunity for animals against brucellosis, the expense of persistent serological responses is one of the main problems of both vaccines. The advantages and limitations of Brucella vaccines, especially new vaccine candidates, have been less studied. In addition, there is an urgent need for new strategies to control and eradicate this disease. Therefore, this narrative review aims to present an updated overview of the available different types of brucellosis vaccines