The Effect of Lactobacillus acidophilus PTCC 1643 on Cultured Intestinal Epithelial Cells Infected with Salmonella enterica serovar Enteritidis

OBJECTIVES: Gastrointestinal disorders caused by Salmonella enterica serovar Enteritidis (SesE) are a significant health problem around the globe. Probiotic bacteria have been shown to have positive effects on the immune responses. Lactobacillus acidophilus was examined for its capability to influence the innate immune response of HT29 intestinal epithelial cells towards SesE. The purpose of this work was to assess the effect of L. acidophilus PTCC 1643 on cultured intestinal epithelial cells infected with SesE. METHODS: HT29 cells were cultured in Roswell Park Memorial Institute medium supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin. The cells were treated with L. acidophilus PTCC 1643 after or before challenge with SesE. At 2 and 4 hours post-infection, we measured changes in the expression levels of TLR2 and TLR4 via real-time polymerase chain reaction. RESULTS: Treatment with L. acidophilus inhibited SesE-induced increases in TLR2 and TLR4 expression in the infected HT29 cells. Moreover, the expression of TLR2 and TLR4 in cells that were pretreated with L. acidophilus and then infected with SesE was significantly higher than that in cells infected with SesE without pretreatment. Taken together, the results indicated that L. acidophilus had an anti-inflammatory effect and modulated the innate immune response to SesE by influencing TLR2 and TLR4 expression. CONCLUSION: Our findings suggested that L. acidophilus PTCC 1643 was able to suppress inflammation caused by SesE infection in HT29 cells and reduce TLR2 and TLR4 expression. Additional in vivo and in vitro studies are required to further elucidate the mechanisms underlying this anti-inflammatory effect.

Genetic profile variation in vaccine strains and clinical isolates of bordetella pertussis recovered from Iranian patients

Re-emergence of pertussis has been reported in Iran despite a high rate of vaccination coverage. Low efficacy of the vaccine might be due to the genetic divergence between Clinical versus vaccine strains. In the current study, the genetic profiles of Clinical isolates and vaccine strains of Bordetella pertussis [B. pertussis] were assessed by using Pulsed Field Gel Electrophoresis [PFGE]. Following phenotypic and molecular identification of isolates, XbaIdigested genomic DNA of 5 Clinical isolates, 2 vaccine strains and a Tohama I strain were analyzed by PFGE along with B. parapertussis as a control. Seven distinct PFGE profiles were found among all examined isolates/strains. In 5 Clinical isolates, 4 profiles were identified whereas the vaccine strains displayed 2 distinct profiles. The reference strain, Tohama I had a distinct profile. Vaccine and Clinical profiles had low similarity, with relatedness of approximately 40%. The genetic profiles of B. pertussis were different between circulating isolates and vaccine strains used in the national vaccination programs. Since new genetic profiles of B. pertussis can be disseminated periodically, the profiles of isolates circulating in the population should be monitored over the course of the re-emergence

Assessment of antibiotic resistance pattern in Acinetobacter baumannii carrying bla oxA type genes isolated from hospitalized patients

Acinetobacter baumannii is a Gram-negative coccobacillus and one of the most opportunistic pathogens responsible for serious infections in hospitalized patients. During a 12 months study, 221 clinical isolates and 22 environmental Acinetobacter baumannii isolates were collected. In vitro susceptibility of Acinetobacter baumannii isolates to 13 antimicrobial agents: amikacin; cefepime; ceftazidime; ciprofloxacin; meropenem; piperacillin/tazobactam; sulfamethoxazole/ trimethoprim; imipenem; tigecycline; colistin; gentamycin; ceftriaxone; levofloxacin was performed by the disk diffusion method. Also Minimum Inhibitory Concentration [MICs] of imipenem; levofloxacin and cefepime was performed by the E-test according to Clinical and Laboratory Standards Institute [CLSI] criteria, blaOXA-23.; blaOXA-24-, blaOXA-58, blaOXA-51genes were detected by polymerase chain reaction and sequencing. The result of antimicrobial susceptibility test of clinical isolates by the disk diffusion method revealed that all strains of Acinetobacter baumannii were resistant to piperacillin/tazobactam. The rates of resistance to the majority of antibiotics tested varied between 69% and 100%, with the exception of tigecycline and colistin. Of 221 isolates tested 99 [44.8%] were XDR. All strains carried a blaOXA-51, like gene. blaOXA-23 gene was the most prevalent among blaOXA-types. Colistin and tigecycline can be effective drugs for treatment of Acinetobacter baumannii infections Continuous Surveillance for Acinetobacter baumannii multidrug-resistant strains is necessary to prevent the further spread of resistant isolates

[Frequency of babA2 genotype in helicobacter pylori from patient with gastroduodenal diseases in Firoozgar Hospital in Tehran]

Blood group antigen binding adhesin [babA2], is essential for attachment of Helicobacter pylori [H. pylori] to the epithelial cell layer and is the most important adhesin of H. pylori. The prevalence rate of the babA2 gene varies in different geographic areas. The aim of this study is to determine the frequency of the babA2 gene in patients with different clinical outcomes. We obtained two gastric biopsy specimens from each patient who suffered from gastrointestinal disease. Rapid urease test [RUT] was performed using one biopsy and the remaining biopsy was delivered to the laboratory for DNA extraction. Prevalence of the babA2 gene was determined using gene specific primers. A total of 56 strains [68.3%] of H. pylori were babA2 positive. The prevalence of babA2 in gastric cancer patients [84.6%] was higher than seen with gastric ulcer [66.7%], duodenal ulcer [61%], and gastric patients [66.7%]. There was no correlation between the babA2 genotype and clinical outcomes. We found that babA2 gene was more prevalent in gastric cancer but no correlation was demonstrated. However, previous studies have demonstrated a correlation of babA2 with severe H. pylori-associated diseases such as duodenal ulcers and gastric cancer. This discrepancy may be related in part to geographic diversity or sample size.

Survey of association between Helicobacter pylori and hepatocellular carcinoma in the specimens derived from health centers of Shahid Beheshti University

Prior investigators demonstrated Helicobacter pylori as a risk factor of liver diseases. In this study association between H. pylori and hepatocellular carcinoma was investigated. Totally, 59 specimens of liver were collected from two health care centers affiliated to Shahid Beheshti University of Medical Sciences, including 22 specimens of hepatocellular carcinoma, 18 specimens of cirrhosis and 19 normal specimens of liver. Polymerase chain reaction was used to determine the presence of H. pylori in liver samples using H. pylori gene-specific primers. 16srRNA of Helicobacter genus were found in 31.8% of hepatocellular carcinoma and 16.7% of cirrhotic specimens, however, we could not find this gene in normal samples. Meanwhile, the presence of ureC and cagA genes specific for H. pylori were investigated in positive specimens to confirm the H. pylori infection, however, these genes were not detected. Helicobacter infection exists in liver of patients with hepatocellular carcinoma. However, further studies are necessary to confirm this association