Cross-Reaction between the Crude Hydatid Cyst Fluid Antigens of Human and Animals Origin in Response to Human IgG Class and Subclasses

The current work aimed to evaluate the cross-reactivity of human immune sera against crude hydatid fluid antigens of sheep, human, mouse, cattle, as well as B fraction of cystic fluid antigen. 30 balb/c mice were infected with sheep hydatid cyct fluid antigen containing protoscolex after the viability of these protoscolices was assessed. ANOVA was used to test the difference of themean of optical density (OD) values among case and control groups. The highest human IgG class antibody was against antigen B (0.93) and the lowest against cattle HCF antigen (0.32). The differences between responses to these antigens were statistically significant (P < 0.001). The sensitivity and specificity of ELISA test used for evaluating the responses of human total IgG to different hydatid cyst fluid (HCF) antigens among the case and control groups were 100 and 95.8%, respectively. Cross-reaction of human IgG class and subclasses responses was found almost for all the antigens with the best reaction against human and cattle (HCF) antigens and antigen B using a ratio of mean OD value to each antigen divided by the cut-off point value for the same antigen. Human sera showed a considerable cross-reactivity against all antigens by using ELISA

Prevalence of OmpK35 and OmpK36 porin expression in beta-lactamase and non-betalactamase- producing Klebsiella pneumoniae

Background: The aims of this study were to confirm the presence of OmpK35 and OmpK36 in extended-spectrum beta-lactamase-producing and nonextended-spectrum beta-lactamase-producing Klebsiella pneumoniae and to determine the relationship between porin expression and resistance to third-generation cephalosporins. Methods: Fifty-two K. pneumoniae isolates were obtained and analyzed for extended-spectrum beta-lactamase and for OmpK35 and OmpK36. Results: Twenty-two (42.3) isolates of K. pneumoniae were extended-spectrum beta-lactamase producers. The OmpK35 profile in K. pneumoniae producing extended-spectrum beta-lactamase showed the presence of porin protein in ceftazidime-sensitive K. pneumoniae (six isolates), and the OmpK36 profile in K. pneumoniae producing extended-spectrum beta-lactamase revealed isolates sensitive to cefotaxime (n = 8) and ceftriaxone (n = 6). All nonextended-spectrum beta-lactamase-producing K. pneumoniae showed the presence of OmpK35 and OmpK36 porin proteins. Conclusion: The presence of OmpK35 is mostly related to ceftazidime susceptibility and less to cefotaxime and ceftriaxone susceptibility, while OmpK36 expression is seen more often in cefotaxime-sensitive isolates. OmpK35 and OmpK36 indicate nonextended-spectrum beta-lactamase producing strains, and their presence is important when selecting an antimicrobial agent. © 2012 Shakib et al

Listeriosis Phytotherapy: A Review Study on the Effectiveness of Iranian Medicinal Plants in Treatment of Listeriosis.

Listeria monocytogenes can be found in many processed foods, raw milk, dairy products, meat and meat products such as sausages, beef and fish products, seafoods, eggs, fruits, and vegetables such as radish and cabbage. This article is a review study on the Iranian medicinal plants applied for treatment of listeriosis. Information of this review article was obtained by searching various key words such as Listeria monocytogenes, medicinal plants, plant extracts and essential oils among scientific articles published in databases of Google scholar, ISI Web of Knowledge, PubMed, Scopus, SID and Magiran. Thyme, German chamomile, great chamomile, yarrow, onion, oregano, nutmeg, sage, sagebrush, hyssop, rosemary, St John's wort, safflower, ajowan, cumin, peppermint, shallot, anise, and parsnip are known antilisteriosis medicinal plants. Bioactive phytochemicals, antioxidants and monoterpenes, sesquiterpene, coumarin, flavonoids, tannins, saponins, alkaloids, and terpenoids are the main ingredients of antilisteriosis medicinal plants

Differential between multi-drug resistance pattern of extended spectrum b- Lactamases producing E. coli and K. pneumoniae

The current study aimed to determine the prevalence of Extended-Spectrum b-Lactamases (ESBLs) in Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) strains isolated from patients with Urinary Tract Infections (UTIs), to study the association between presence of ESBL enzyme and multi-drug resistance strains and finally, and to investigate the predominant ESBL gene in E. coli and K. pneumoniae. The strains were examined for the presence of ESBL as a Clinical Laboratory Standards Institute (CLSI) guideline. Among 284 clinical isolates, 52.8% (n = 150) and 47.2% (n =134) were E. coli and K. pneumoniae, respectively, and 110 strains were ESBL producer, which 68 strains were K. pneumoniae and 42 strains were E. coli. Significant difference observed between the TEM gene and ciprofloxacin resistant in E. coli (P ? 0.05) while no significant difference observed between CTX-M, SHV genes and the other multi-drug resistant E. coli. No significant difference observed between CTX-M, TEM, and SHV genes and multi-drug resistant K. pneumoniae. In conclusion, spreading of ESBL-producing strains is a concern, as it causes limitations to the antimicrobial agents for optimal treatment of patients. Prevalence of ESBLs was more observed in K. pneumoniae than E. coli. In addition, TEM gene was more prevalent in E. coli and resistance to ciprofloxacin was predominant in E. coli

Relationship between the Presence of the nalC Mutation and Multidrug Resistance in Pseudomonas aeruginosa

Objectives. The current study was conducted to determine the relationship between the presences of significant multidrug resistance in Pseudomonas aeruginosa (P. aeruginosa) having intact mexR genes (nalC) to different antibiotics. Methods. In order to identify nalC, fifty strains of P. aeruginosa were obtained. All isolates were found in urinary tract infections. They were evaluated against different antibiotics. The nalC mutant was identified by PCR. Results. The 50 clinical isolates of P. aeruginosa originated from two hospitals in Iran, in which 32 isolates were found in Milad hospital, and 18 isolates were collected in the Ilam Hospital. The results in Milad hospital of nalC revealed that all P. aeruginosa resistant to oxacillin showed the presence of nalC. In Ilam hospital only three (16.6%) isolates were resistant to oxacilin and aztreonam, and among these three isolates only one isolate revealed resistance to ceftazidime and amikacin. The resistant isolates showed the presence of both OXA-10 and nalC. Conclusion. Our results showed that the presence of nalC was observed among P. aeruginosa resistance to oxacilin. Thus, the finding suggested relationship between oxacilin resistance and presence of nalC and consequently overproduction of the MexABOprM efflux system

The Prevalence of ESBLs Producing Klebsiella pneumoniae Isolates in Some Major Hospitals, Iran

Aims of this study were to investigate on antibiotic resistance and molecular epidemiology of K.pneumoniae producing ESBLs isolates of respiratory tract infections in some major hospitals in Iran. K.pneumonaie were obtained of patients with RTI. K. pneumoniae producing ESBLs detected by screening, confirming and PCR methods. During the 12-month period, a total of one hundred and thirteen of K.pneumoniae were found from RTI in three cities in different region of Iran which Sixty seven strains (59.2%) were ESBLs producer. In Ilam hospitals, seventeen strains (43.6%), in Milad hospital, thirty-seven strains (74%) and in Emam Reza hospital, thirteen strains (54.2%) were ESBLs producer. The findings showed that among sixty-seven K.pneumoniae producing ESBLs, Sixty-three strains (94%) were positive for blaSHV, eleven strains (16.4%) contained blaTEM and sixteen strains (23.9%) harbored blaCTX-M. Imipenem was found as an effectiveness antibiotic. In the current study, Majority of the ESBLs production had occurred in Milad hospital in Tehran (74%). In conclusion, spreading ESBL-producing strains is a concern, as it causes limitations to the antimicrobial agents for optimal treatment of patients

Comparison of toxin-antitoxin expression among drug-susceptible and drug-resistant clinical isolates of Mycobacterium tuberculosis

Introduction: Mycobacterium tuberculosis (MTB), the causative agent of tuberculosis (TB), is a significant global public health threat. Besides extensive multidrug resistance, MTB possesses several properties for long-term viability in the host as well as stress adaptation and resistance in harsh conditions. The role of toxin-antitoxin (TA) systems in disseminating and maintaining antimicrobial resistance in bacterial populations has also been demonstrated. This study aimed to evaluate differences in expression of MazEF (a well-known TA system) related genes (mazE3, mazF3, mazE6, and mazF6) amongst drug-susceptible and resistant MTB isolates in Iran.Material and methods: A total of 20 confirmed clinical isolates of MTB including 10 drug-susceptible and 10 drug-resistant (nine MDR, and one XDR) species were included in this study. M. tuberculosis H37Rv was used as the standard strain. RNA extraction, cDNA synthesis, and relative quantitative real-time PCR were performed according to the standard procedures.Results: Our analysis indicated significant enhanced expression of the mazE6 antitoxin gene in drug-susceptible isolates compared to drug-resistant isolates and the standard strain. The expression of the mazF6 toxin gene was also increased in drug-susceptible isolates compared with the standard strain. In drug-resistant isolates, the expression levels of mazF3 and mazF6 genes were significantly higher than that in the susceptible isolates and the standard strain.Conclusions: In this study, there was significant overexpression of mazE6 in drug-susceptible isolates. As well, mazF3 and F6 were overexpressed in drug-resistant isolates when compared with the standard strain. The changes in expression levels of MazEF6 associated genes were greater than that of MazEF3 in both groups of isolates

Phenotypic and genotypic assay for detection of extended spectrum B-lactamases production by Klebsiella pnemoniae isolates in Emam Reza Hospital in Tabriz, Iran.

Objectives of this study were to investigate the prevalence of K. pneumoniae producing ESBLs, to evaluate the susceptibility of K. pneumoniae producing ESBLs towards non-beta-lactam antibiotics and to study the dominant ESBLs gene in Emam Reza hospital. K. pneumoniae producing ESBLs identified by phenotypic and genotypic methods. Polymerase Chain Reaction (PCR) performed for detection of blaSHV, TEM and CTX-M. The findings showed that 43.69%, 13.59%, 7.77%, 11.65% and 23.3% were from UTI, ICUs, surgery ward, lesion infections and RTI, respectively. The results showed that 43.7% of isolates were ESBLs produces. The findings revealed that 26.7%, 6.7%, 20% and 0% of K.pneumoniae producing ESBLs were resistant to amikacin, ciprofloxacin, cotrimoxazol and imipenem, respectively. Thirty-nine blaSHV, seven blaTEM and seven blaCTX-M identified among K.pneumoniae producing ESBLs. The results reflected in cold month resistant to third generation cephalosporins were more than warm months. Generally, frequency of blaSHV was more than blaCTX-M and blaTEM

The mazef toxin-antitoxin system as an attractive target in clinical isolates of Enterococcus faecium and Enterococcus faecalis

The toxin-antitoxin (TA) system is a regulatory system where two sets of genes encode the toxin and its corresponding antitoxin. In this study, the prevalence of TA systems in independently isolated clinical isolates of Enterococcus faecium and Enterococcus faecalis was determined, the dominant TA system was identified, different virulence genes in E. faecium and E. faecalis were surveyed, the level of expression of the virulence and TA genes in normal and stress conditions was determined, and finally their associations with the TA genes were defined. Remarkably, the analysis demonstrated higBA and mazEF in all clinical isolates, and their locations were on chromosomes and plasmids, respectively. On the other hand, a quantitative analysis of TA and virulence genes revealed that the expression level in both genes is different under normal and stress conditions. The results obtained by anti-mazF peptide nucleic acids demonstrated that the expression level of virulence genes had decreased. These findings demonstrate an association between TA systems and virulence factors. The mazEF on the plasmids and the higBA TA genes on the chromosomes of all E. faecium and E. faecalis strains were dominant. Additionally, there was a decrease in the expression of virulence genes in the presence of anti-mazF peptide nucleic acids. Therefore, it is suggested that mazEF TA systems are potent and sensitive targets in all E. faecium and E. faecalis strains