Microbiology
Fatemeh Amraei; Negar Narimisa; Behroz Sadeghi; Vahid Lohrasbi; Faramarz Masjedian Jazi
Abstract
Background & Objective: Persister cells are defined as a subpopulation of bacteria that are capable of reducing their metabolism and switching to dormancy in stress conditions. Persister cells formation has been attributed to numerous mechanisms, including stringent response and Toxin-Antitoxin (TA) ...
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Background & Objective: Persister cells are defined as a subpopulation of bacteria that are capable of reducing their metabolism and switching to dormancy in stress conditions. Persister cells formation has been attributed to numerous mechanisms, including stringent response and Toxin-Antitoxin (TA) systems. This study aimed to investigate the hypothetical role of TA systems in persister cells formation of Brucella strains by evaluating toxins of type II TA systems (RelE, Fic, Brn T, cogT) expression. Methods: Brucella strains treated with a lethal dose of gentamicin and ampicillin and to determine the number of surviving cells, bacterial colonies were counted at different time intervals. The role of TA systems in persister cell formation was then determined by toxin expression levels using qRT- PCR method. Result: Our results showed the viability of persister cells after 7 h. The results of relative qRT- PCR showed higher levels of toxin gene expression due to stress conditions, suggesting the possible role of TA systems in persister cells formation and antibiotics tolerance. Conclusion: The results of this study showed that considering the importance of persistence and the tolerance to antibiotics, further studies on persister cells formation and related genes such as the TA system genes in Brucella strains might help us to identify the precise mechanisms leading to persister cells formation.
Molecular Pathology
Navid Bazzaz; Nazila Nouraee Nouraee; Ali Zare-Mirzaie; Seyed Javad Mowla Mowla; Maryam Shahali; Mohammad Vasei
Volume 13, Issue 4 , October 2018, , Pages 422-428
Abstract
Background and Objective: Wilms’ tumor (WT) is the most common genitourinary tract tumor in children. MicroRNAs (miRNAs) are small non-coding RNAs; their role in the pathogenesis of many types of human cancers has been identified. We aimed to evaluate the expression of miR-21, a well-known oncomir, ...
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Background and Objective: Wilms’ tumor (WT) is the most common genitourinary tract tumor in children. MicroRNAs (miRNAs) are small non-coding RNAs; their role in the pathogenesis of many types of human cancers has been identified. We aimed to evaluate the expression of miR-21, a well-known oncomir, in WT tissue samples which is a very common urinary tract malignancy in children. Methods: We performed chromogenic in situ hybridization (CISH) to detect the sub-cellular localization of miR-21 in 25 formalin-fixed, paraffin-embedded (FFPE) samples of WT. We also evaluated miR-21 expression in 24 of these blocks and 6 normal kidneys as controls using quantitative real-time PCR technique. Results: While our real-time PCR analysis showed miR-21 significant overexpression in 4 tumors compared to the normal kidney samples, we could not detect significant ISH signal in any of these samples. Conclusion: Low expression of miR-21 in WT might pinpoint the weak involvement of this miRNA in the pathogenesis of this cancer.
Microbiology
Shadi Shahsavan; Parviz Owlia; Abdolaziz Rastegar Lari; Bita Bakhshi; Maliheh Nobakht
Abstract
Background: Shigella spp. are gram negative bacteria, which are of global public health importance. The growing of multidrug-resistant Shigella isolates are a major problemaround the world. Methods: Overall, 50 isolates of Shigella spp. from children diarrheic stools were studied. ...
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Background: Shigella spp. are gram negative bacteria, which are of global public health importance. The growing of multidrug-resistant Shigella isolates are a major problemaround the world. Methods: Overall, 50 isolates of Shigella spp. from children diarrheic stools were studied. The isolates were identified and confirmed using biochemical, serological and molecular methods (ipaH, wbgZ and rfc genes). Antimicrobial susceptibility test was done according to the Clinical and Laboratory Standards Institute (CLSI) guidelines against minocycline, tetracycline, doxycycline, ampicillin, streptomycin, trimethoprim-sulfamethoxazole, nalidixic acid, norfloxacin, ciprofloxacin and levofloxacin. Also, the role of efflux pump in defense of Shigella against tetracycline was investigated by Minimum Inhibitory Concentration (MIC) with and without an efflux pump inhibitor. Detection of tetA, tetB, tetC and tetD genes in Shigella was evaluated by conventional Polymerase Chain Reaction (PCR) and real time PCR. Results: Molecular identification revealed a prevalence of 14% for Shigella flexneri and 86% for Shigella sonnei. Minimum Inhibitory Concentration (MIC) of 90% of resistant isolates was changed in the presence CCCP.Results of conventional PCR exhibited that 66% of isolates were positive for tetA, while according to real time PCR method, 90% of isolates carried tetA. Positive results for tetB were12% and 18% by conventional and real time PCR methods, respectively. No positive results were detected for tetC and tetD. Also, tetB was detected only in S. flexneri while tetA was detected in both S. flexneri and S. sonnei. Conclusion: It seems that efflux-mediated tetracycline resistance to tetracycline in S. flexneri can be related to tetB, however resistance in S. sonnei can be related to the expression of tetA.
Biology & Genetic
Shahriar Dabiri; Mohammadmehdi Moeini aghtaei; Jahanbano Shahryari; Manzume Shamis meymandi; Sahar Amirpour-Rostami; Reza Foutohi-Ardekani
Volume 11, Issue 2 , April 2016, , Pages 104-111
Abstract
Background: The breast cancer is the most prevalent cancer among women, on the other hand absence of myoepithelial cells play a pivotal role in pathogenesis of this cancer. Thus we aimed to investigate the possible abilities of the molecular assay technique to find a relationship between mammary serine ...
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Background: The breast cancer is the most prevalent cancer among women, on the other hand absence of myoepithelial cells play a pivotal role in pathogenesis of this cancer. Thus we aimed to investigate the possible abilities of the molecular assay technique to find a relationship between mammary serine protease inhibitor (Maspin) gene expression possibly secreted by myoepithelial cells, grade of breast cancer and other prognostics factors (ER, PR, and c-erb-B2). Methods: Paraffin embedded blocks of 31 breast cancer patients together with two normal breast tissues were used for IHC staining and Maspin gene RNA detection uses the real-time PCR method. Applying QIAGEN kit, we were able to measure Maspin RNA and Extract the cDNA of different samples for evaluating the Maspin RNA level. Results: We found that the RNA level was considerably lowerin these cancer samples compared with normal samples. In addition, different grades of breast cancer in the obtained results adopt some distinguishable values. The Maspin expression in samples with grades II and III is much lower than the ones in normal group (P<0.05) which could be considered as a promising way in diagnosing of this disease. The results showed no considerable differences in Maspin gene expression of the c-erb-B2 scores in the tumor group except the samples having score 0. The other observation of this research study confirmed that Maspin gene expression couldn't show any differences between the values of both ER and PR in different scores of the tumor group. On the other hand, the cDNA of these patients showed lower values compared with normal samples. Conclusion: Maspin expression was reduced in samples with grade II& III of invasive ductal carcinoma. Based on expression of Maspin Inc-erb-B2, it seems that more expression happened in normal group comparing with different scores of it. We could suggest that there was a reverse relationship between tumor formation and Maspin gene expression. These results showed possible role of Maspin as prognostic factor.
