Impacts of the Staphylococcal Enterotoxin H on the Apoptosis and lncRNAs in PC3 and ACHN.

Cancer is considered as the most lethal disease for human beings, and up to now many attempts were failed for prevention and treatment of this tremendous health problem. Consequently, this study purpose was to investigate novel therapeutic methods for cancer. The bacterial toxin can result in cell death throughout the induction of apoptosis in cancer cell lines. We evaluated apoptosis and the expression levels of long non-coding RNAs (lncRNAs) in PC3, ACHN and HDF cell lines that were transfected with pCDNA3.1(+)-seh and empty plasmid. pCDNA3.1(+)-seh treatment showed overexpression of GAS5 (p = 0.0033 and p = 0.0033) in PC3 and ACHN cells, down regulation of PCA3 and NEAT1 (p = 0.0092 and p = 0.0097) in the PC3 cells, and down regulation of PVT1 and MALAT1 (p = 0.0239 and p = 0.0133) in the ACHN cells in comparison with the empty plasmid, but there was no significant effect on HDF normal cells. Additionally, this study data demonstrated that the cell adhesion was down regulated. The flow cytometry data showed transfection by pCDNA3.1 (+)-seh could elevate PC3 and ACHN cell apoptosis levels in comparison with empty plasmid. This study findings propose that SEH toxin of S. aureus could be a useful candidate for therapeutic researches in cancer vaccine development.

Multiplex touchdown PCR assay to enhance specificity and sensitivity for concurrent detection of four foodborne pathogens in raw milk.

AIMS: The aim of this study was to develop a multiplex touchdown PCR (multiplex TD-PCR) for rapid and simultaneous detection of four major foodborne pathogens to avoid mispriming and unwanted production during gene amplification. Touchdown PCR is the modified form of standard PCR, which enhances specificity, sensitivity. METHODS AND RESULTS: For this reason, a multiplex TD-PCR assay with a pre-enrichment step was developed to detect four foodborne pathogens namely Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Salmonella enterica serovar Enteritidis in pure culture and raw milk samples. The results showed that this protocol can eliminate the unwanted band or reduce significantly. The detection sensitivity of the single and multiplex TD-PCR was one cell per ml in pure culture. Furthermore, the detection limit of multiplex TD-PCR was one cell per 25 ml for artificially contaminated raw milk. We obtained similar results for detection of aforementioned pathogens in raw milk, after comparing the multiplex TD-PCR method with the traditional culture, except in one or two samples. CONCLUSIONS: Hence, the proposed multiplex TD-PCR method could be confirmed as an effective way for rapid optimization of PCR reactions to increase specificity, sensitivity during gene amplification. SIGNIFICANCE AND IMPACT OF THE STUDY: Hence, due to its simplicity, cost-effectiveness and being time-saving, it seems that this method is reasonable and economical for rapid optimization of PCR reactions.

Construction and evaluation of a whole-cell pneumococcal vaccine candidate.

AIMS: Pneumococcal infections are a major public health problem, especially in developing countries, and the current pneumococcal vaccines do not cover all pathogenic strains. New, more economical serotype-independent vaccines based on species-common protein antigens are being pursued. The pneumococcal whole-cell vaccine which is based on noncapsular antigens common to all strains induces serotype-independent immunity. In the present study, we developed a new candidate for a whole-cell pneumococcal vaccine in which two important virulence factors, the capsule and pneumolysin, were deleted. METHODS AND RESULTS: Protection was elicited by immunization against colonization in mice with a killed mutant strain and the antibody response in the mice serum was evaluated. This candidate vaccine was effective in preventing nasopharyngeal colonization. The mice immunized with this candidate vaccine had significantly higher serum antibody titres than mice that received the adjuvant alone. CONCLUSIONS: Based on obtained results in this study, the engineered whole-cell pneumococci can be considered as a vaccine candidate in future studies. SIGNIFICANCE AND IMPACT OF THE STUDY: This candidate vaccine can overcome the limitations of available polysaccharide vaccines.

Molecular detection of bovine leukemia virus in peripheral blood of Iranian cattle, camel and sheep.

Bovine leukemia virus (BLV) is a deltaretrovirus which infects and induces proliferation of B-lymphocytes in the peripheral blood circulation and in lymphoid organs primarily of cattle, leading to leukemia/lymphoma. This study was carried out to investigate the presence of BLV in cattle, sheep and camels from the Chaharmahal va Bakhtiary and Isfahan provinces in Iran. A total of 874 blood samples collected from cattle, sheep and camels were used in this study to detect BLV using a nested-PCR. The results from this study indicated that 17.2% (n=874) of all blood samples collected were positive for BLV. The percentages of blood samples positive for BLV from cattle, sheep and camels were 22.1 (n=657), 5.3 (n=95) and 0 (n=122) respectively. The results from this study showed that BLV infected cattle and sheep. Camels seemed to be resistant to BLV infection. This study contributes to the nationwide effort to obtain baseline information on the prevalence of BLV, which will assist in planning the control strategy for the disease in Iran.

Detection of Coxiella burnetii by nested PCR in bulk milk samples from dairy bovine, ovine, and caprine herds in Iran.

The epidemiology of Q-fever in Iran is essentially unknown. This study was conducted to determine the prevalence rate of Coxiella burnetii in bulk milk samples from dairy bovine, ovine, and caprine herds in Chaharmahal va Bakhtiari province, Iran. In this study, 376 bulk milk samples from 79 dairy bovine, ovine, and caprine herds were tested for C. burnetii using a nested PCR assay. The animals whose milk samples collected for this study were clinically healthy. In total, 13 of 210 (6.2%) bovine milk samples were positive; the positive samples originated from 5 of 28 (17.9%) commercial dairy herds. All 110 ovine bulk milk samples from 31 sheep breeding farms were negative and only 1 of 56 (1.8%) caprine bulk milk samples from 20 goat breeding farms was positive for C. burnetii. Although no extensive prevalence study was undertaken, the results of this study indicate that clinically healthy cattle are important sources of C. burnetii infection in Iran. To our knowledge, this study is the first report of direct identification of C. burnetii by PCR in bulk milk samples from dairy bovine and caprine herds in Iran. Further intensive prevalence studies on Coxiella infection among farmers, milk-processing workers, veterinarians, and slaughterhouse workers and on possible dangers of dairy products will be needed to elucidate the epidemiology of Q fever in Iran.

Role of NADPH-insensitive nitroreductase gene to metronidazole resistance of Helicobacter pylori strains.

BACKGROUND AND THE PURPOSE OF THE STUDY: Current anti-H. pylori therapies are based on the use of two antibiotics with a proton pump inhibitor and/or a bismuth component. Metronidazole is a key component of such combination therapies in Iran. The aim of this study was to determine the role of rdxA gene in resistant strains of H. pylori isolated from Shahrekord Hajar hospital to metronidazole. METHODS: This study was a cross-sectional method, which was carried out on 263 patients who referred to endoscopy department of Hajar hospital, in 2007. Biopsy samples were cultured on selective Brucella agar containing 10% blood and incubated under microerophilic condition at 370C for 3-7 days. Suspected colonies were tested by Gram staining, urease, oxidase and catalase activities. Organisms were confirmed to be H. pylori on the basis of the presence of ureC(glmM) gene by PCR.Specific primers were used for detection of rdxA gene mutation. RESULTS: Eighty and four strains of H. pylori determined by PCR method. Of the isolated strains, 49 (58.33%) were resistant, 7 (8.33%) were semi-sensitive to metronidazole and 200bp deletion in rdxA gene was observed in 2 strains. CONCLUSION: Because of the high metronidazole resistance in patients under study it was necessary to replace it by other antibiotics in therapeutic regimens. On the basis of low frequency of resistance mutation in rdxA gene, sequence analysis for identification of other mechanisms is suggested.