مقالات  دکتر محمد علي حقيقي  


  Wide distribution of carbapenem resistant Acinetobacter baumannii in burns patients in Iran Frontiers in Microbiology 2015 | Volume 6 If:4.5 Zahra Farshadzadeh, Farhad B. Hashemi, Sara Rahimi, Babak Pourakbari, Davoud Esmaeili, Mohammad A. Haghighi, Ali Majidpour, Saeed Shojaa , Maryam Rahmani, Samira Gharesi, Masoud Aziemzadeh and Abbas Bahador 6 از 12
Antimicrobial resistance in carbapenemn on susceptible Acinetobacter baumannii (CNSAb) is a major public health concern globally. This study determined the antibiotic resistance and molecular epidemiology of CNSAb isolates from a referral burn center in Tehran , Iran . Sixty- nine CNSAb isolates were tested for susceptibility to antimicrobial agents using the E test methodology. Multiple locus variable number tandem repeat analysis (MLVA), Multilocus sequence ping (MLST) and multiplex PCR were performed . PCR assay s tested f or ambler classes A, B , and D β -lactamases . Detect ion of ISAba1, characterization of integrons, and biofilm formation were investigated. Fifty-three (77%) isolates revealed XDR phenotypes. High prevalence of blaOXA−23-like (88%) and blaPER −1 (54%) were detected. ISAba1 was detected upstream of blaADC, blaOXA−23- like and blaOXA51 -like genes in, 97, 42, and 26% of isolates, respectively. Thirty-one (45%) isolates were assigned to international clone (IC) variants. MLVA identified 56 distinct types with six clusters and 53 singleton genotypes. Forty previously known MLST sequence types forming 5 clonal complexes were identified. The Class 1 integron (class 1 integrons) gene was identified in 84% of the isolates. The most prevalent (33%) cassette combination was aacA4-catB8-aadA1. The IC variants were predominant in the A. baumannii lineage with the ability to form strong biofilms. The XDR-CNSAb from burned patients in Iran is resistant to various antimicrobials, including tigecycline. This study shows wide genetic diversity in CNSAb. Integrating the new Iranian A. baumannii IC variants into the epidemiologic clonal and susceptibility profile databases can help effective global control measures against the XDR-CNSAb pandemic

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doi:10.3389/fmicb.2015.01146

  Application of Bioinformatics and Genetic Engineering for Designing Optimized Cloning and Overexpression of Neutrophil Activating Protein of Helicobacter pylori in Escherichia coli مجله علمی پژوهشی دانشگاه علوم پزشکی زنجان دوره 21 شماره 85 سال 92 علمی پزوهشی نمایه شده در scopus Haghighi MA, Mohabati Mobarez A, Salmanian AH, Zali MR, Moazzeni SM, Karkhane AA 1 از6
Background and Objective: As the main virulence factor of Helicobacter pylori, HP-NAP has an important role in immunoprotection against this pathogen. This antigen is a strong candidate as a part of multicomponent vaccine in the clinical trial against this bacterium. Due to NAP importance, it was used in this study as a template for optimization of heterologous genes with a low A-T content and low expression in E. coli. Materials and Methods: A synthetic single gene that could reach the highest level of expression in the host was designed by using bioinformatics tools. Results: A number of factors that influence gene expression level were changed for HP-NAP gene optimizing: the codon usage bias in E. coli was changed; the G+C content was upgraded from 38% to 45%; and the stem-loop structure was broken. These could result to prolong of the half-life of the mRNA and overexpression of recombinant of HP-NAP protein up to 800 mg per liter. Conclusion: Applying of bioinformatics tools was appropriated to optimize of HP-NAP overexpression in E.coli. From our results, it appears that combination of In Silico and experimental approach is a logical approach for expression of heterologous genes in another host.

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  In silico experiment with an antigen-toll-like receptor-5 agonist fusion construct for immunogenic application to Helicobacter pylori Indian Journal of Human Genetics 2013 Volume 19 Issue 1 نمایه شده در Pub-med Mohamad Ali Haghighi, Ashraf Mohabati Mobarez, Ali Hatef Salmanian, Mohamad Moazeni, Mohamad Reza Zali, Mehdi Sadeghi, Jafar Amani 1 از 7
BACKGROUNDS: Helicobacterpylori colonize the gastric mucosa of half of the world’s population. Although it is classifid as a defiitive type I carcinogen by World Health Organization, there is no effective vaccine against this bacterium. H. pylori evade the host immune response by avoiding toll‑like detection, such as detection via toll‑like receptor‑5 (TLR‑5). Thus, a chimeric construct consisting of selected epitopes from virulence factors that is incorporated into a TLR‑5 ligand (Pseudomonas flgellin) could result in more potent innate and adaptive immune responses. MATERIALS AND METHODS: Based on the histocompatibility antigens of BALB/c mice, in silico techniques were used to select several ragments from H. pylori virulence factors with a high density of B‑ and T‑cell epitopes. RESULTS: These segments consist of ytotoxin‑associated eneA (residue 162‑283), neutrophil activating protein (residue 30‑135) and outer inflmmatory protein A (residue 155‑268). The secondary and tertiary structure of the chimeric constructs and other bioinformatics analyses such as stability, solubility, and antigenicity were performed. The chimeric construct containing antigenic segments of H. pylori proteins was fused with the D3 domain of Pseudomonas flgellin. This recombinant chimeric gene was optimized for expression in Escherichia coli. The in silico results showed that the conserved C‑ and N‑terminal domains of flgellin and the

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www.ijhg.com DOI: 10.4103/0971-6866.112885

  Preparation of chitosan nanoparticles carrying recombinant helicobacter pylori neutrophil-activating protein مجــلــــه دانـشـــگاه عــلـــوم پــزشــكــــي مــازنـــدران volume 135,2014 علمی پزوهشی نمایه شده در scopus Neda Soleimani, Ashraf Mohabati-Mobarez, Fatemeh Atyabi, Zohair Hasan-Saraf, Mohammad-Ali Haghighi 5 از 5
Background and purpose: Breast cancer is one of the leading causes of death in women around the world with a very high degree of mortality and morbidity. Conventional treatments use cytotoxic drugs which have high levels of side effects, affecting the patient’s quality of life. Therefore today’s pharmacology is looking into treatments with low side effects and maximum efficiency. The helicobacter pylori neutrophil-activating protein (HP-NAP) is a virulence factor that attracts and activates neutrophils, and promotes their endothelial adhesion and the production of oxygen radicals and chemokines. HP-NAP is an immune modulator able to induce the expression of IL-12 and IL-23. Chitosan is biodegradable and biocompatible component. It is low toxicity effect, so apply in drug delivery targets. In this study, we evaluated the preparation of chitosan nanoparticles carrying recombinantHP-NAP helicobacter pylori. Materials and methods: Chitosan nanoparticles were produce. The size and morphology of the nanoparticles were investigated. Recombinant HP-NAP helicobacter pylori were produce. Results: SDS-PAGE analysis showed the expression of an approximately 20,000 Dalton protein. DLS confirm size and zeta potential of the nanoparticle. Conclusion: The complex has the potential to shift antigen-specific T-cell responses from a predominant Th2 to a polarized Th1 cytotoxic phenotype, characterized by high levels of interferon-γ and tumor necrosis factor-a production. HP-NAP may be a new tool for future therapeutic strategies aimed in cancer immunotherapy. Nanomaterials have been used to enable drug delivery with lower toxicity to healthy cells and enhanced drug delivery to tumor cells.

  Growth Rate and Biofilm Formation Ability of Clinical and Laboratory-Evolved Colistin-Resistant Strains of Acinetobacter baumannii Frontiers in Microbiology February 2018 | Volume 9 Open access Q1 ششم از هفتم
Two different mechanisms of resistance to colistin in Acinetobacter baumannii have been described. The first involves the total loss of lipopolysaccharide (LPS) due to mutations in the lpxACD operon, which is involved in the lipid A biosynthesis pathway. The second entails the addition of ethanolamine to the lipid A of the LPS resulting from mutations in the PmrAB two-component system. To evaluate the impact of colistin resistance-associated mutations on antimicrobial resistance and virulence properties, four pairs of clinical and laboratory-evolved colistin-susceptible/colistinresistant (ColS/ColR) A. baumannii isolates were used. Antimicrobial susceptibility, surface motility, in vitro and in vivo biofilm-forming capacity, in vitro and in vivo expression levels of biofilm-associated genes, and in vitro growth rate were analyzed in these strains. Growth rate, in vitro and in vivo biofilm formation ability, as well as expression levels of biofilm-associated gene were reduced in ColR LPS-deficient isolate (the lpxD mutant) when compared with its ColS partner, whereas there were not such differences between LPS-modified isolates (the pmrB mutants) and their parental isolates. Mutation in lpxD was accompanied by a greater reduction in minimum inhibitory concentrations of azithromycin, vancomycin, and rifampin than mutation in pmrB. Besides, loss of LPS was associated with a significant reduction in surface motility without any change in expression of type IV pili. Collectively, colistin resistance through loss of LPS causes a more considerable cost in biological features such as growth rate, motility, and biofilm formation capacity relative to LPS modification. Therefore, ColR LPS-modified strains are more likely to spread and transmit from one patient to another in hospital settings, which results in more complex treatment and control.

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www.frontiersin.org

  The Relationship Between Antibiotic Resistance Phenotypes and Biofilm Formation Capacity in Clinical Isolates of Acinetobacter baumannii Jundishapur Journal of Microbiology 2018 July 18 Sara Rahimi, Zahra Farshadzadeh, Behrouz Taheri, Mohsen Mohammadi, Mohammad-Ali Haghighi, and Abbas Bahador پنجم از ششم
Background: Understanding of the biological factors responsible for prevalence and persistence of Acinetobacter baumannii in hospital settings is critical to prevent and control the corresponding nosocomial infections. Objectives: This study was conducted to investigate whether the biofilm-forming ability is associated with the emergence of different antibiotic resistance phenotypes [multidrug resistance (MDR)/extensively drug resistance (XDR) and non-MDR] of A. baumannii. Methods: The capacitiesof biofilmformation in 80 clinicalA. baumanniistrains isolatedfromhospitalized burn patients inBushehr, Iran, were assessed using the crystal violet staining. Results: The statistical analysis of the relationship between biofilm-forming ability and antibiotic resistance phenotypes among all clinical A. baumannii strains using one-way ANOVA test indicated that biofilm formation capacity of non-MDR A. baumannii isolates was significantly higher than that of MDR and XDR ones (P < 0.001), suggesting an inverse relationship between biofilm formation capacity and the acquisition of MDR/XDR phenotypes. Major international clonal types(ICI and ICII) also exhibited such a significant relationship (P < 0.0001). However, the investigation of A. baumannii IC variants showed no significant relationship between these phenotypes. Conclusions: Given that non-MDR A. baumannii isolates in major IC types were observed to form a strong biofilm compared to MDR/XDR ones, it seems that biofilm may play a key role in the persistence and survival of A. baumannii isolates with an inadequate level of antibiotic resistance. Furthermore, the results showed that the relationship between biofilm and antibiotic resistance phenotypes might be affected by the IC types (major IC types or IC variants).

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  PCR Identification of Escherichia coli Isolated from Bushehr Coastal Water Iran South Med J علمی پژوهشی چهارم از چهار
Background: Standard methods of identification have not been able to solve all issues concerning E. coli. With the development of genomic studies, PCR appears promising to deal with the shortcomings. This study aimed to utilize PCR with specific primers for lacZ, uidA, cyd, and lacY gene segments to identify environmental E. coli isolates. Materials and methods: PCR and the aforementioned four primers were used for molecular identification of E. coli on purified genome DNA from 120 environmental E. coli isolates, standard strains of Shigella, and Enterohaemorrhagic E. coli strain as controls. All environmental E. coli isolates were isolated from Bushehr coastal areas and identified in a previous study by standard bacteriological methods and then preserved in -70 C for further studies. Results: The primers successfully showed their ability to identify the targets in environmental isolates and standard strains. It is shown that the four PCR fragments related to lacZ, uidA, cyd, and lacY genes were observed only for E. coli isolates and strains. Conclusion: PCR method proved capable to distinguish E. coli from Shigella as the most phylogenetically related genus and contrary to the classical methods, it could detect enterohaemorrhagic strains as Escherichia coli.

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http://ismj.bpums.ac.ir

  Presence of Shiga Toxin Gene in Clinical Isolates of Shigella Species from the Past to Present in Bushehr, Iran Iran South Med J 2018 علمی پژوهشی G. Noorabadi (MSc)1*, M. Siyavashi (MSc)1, K. Vahdat (MD)2, O. Gharibi (BS)3, M. Mahmudpour (MD)2, MA. Haghighi (PhD)2,4** ششم از شش
Background: The Shiga cytotoxin (Stx) is involved in serious human intestinal diseases. Recently stx has been found in non-S dysenteriae1 Shigella species. This study aimed to identify stx gene in clinical strains of Shigella isolated from two shigellosis outbreaks in previous years in Bushehr, southwest of Iran. Materials and Methods: Purified DNA of 143 Shigella isolates was used for PCR to detect stx and ipaH genes. The number of PCR products in various Shigella species isolates was sequenced with the same primers (evt) used to amplify this region. Results: Fourteen (22.3%) out of 63 shigella isolates related to previous shigellosis outbreaks during 2002-2004 contained the PCR positive result with evt primers .The sequencing results indicated that the evt PCR product had the most identity (97%) with Shigella dysentery shiga toxin subunit A. All clinical shigella strains isolated during 2013-2015 yielded PCR negative results with primers stx and evt. PCR results revealed that ipaH was present in all isolates. According to biochemical and species-specific antiserum tests, the stx gene harboring isolates included 9 (14.3%) S. flexneri, 4 (6.4%) S. sonnei, and 1(1.6%) S. boydii. Conclusion: The stx gene has already been distributed in different Shigella species of Bushehr region. However, the absence of this gene in the clinical isolates of recent shigellosis outbreaks may be temporary. Because stx gene increases the pathogenic potential of Shigella, it is necessary to monitor the prevalence of the stx harboring Shigella species by molecular methods in the future.

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http://ismj.bpums.ac.ir


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