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فهرست مطالب seyed mahmoudamin marashi

  • زهرا قربانی، مریم کوپایی، حوریه صادری، سید محمود امین مراشی، زهرا دهقان زاده، پرویز اولیا*
    زمینه و اهداف

      پسودوموناس آئروژینوزا یک پاتوژن مهم در همه جا و به ویژه شایع در بیمارستان است. اگزوتوکسین A کدگذاری شده توسط ژن exoA در پاتوژنز این باکتری نقش دارد. امروزه پروبیوتیک ها به طور گسترده در درمان و پیشگیری از بیماری ها استفاده می شوند. مطالعه حاضر با هدف بررسی اثر ساکارومایسس سرویزیه S3 بر بیان ژن exoA انجام شد.

    مواد و روش کار

      رویی S. cerevisiae و لیز تهیه شد. کمترین غلظت بازدارنده (sub-MIC) عصاره ها برای P. aeruginosa PAO1 استفاده شد. سطح بیان exoA با روش Real-time PCR اندازه گیری شد.

    یافته ها

      عصاره لیزات اثر کاهشی بر بیان ژن توکسین داشت، اما بر خلاف لیز، مایع رویی اثر افزایشی بر بیان ژن داشت.

    نتیجه گیری

      نتایج این مطالعه نشان می دهد ویروس های پاپیلومای ژنوتیپ 16 و18 فراوان ترین ژنوتیپ در درجات مختلف ضایعات بافتی دهانه رحم است. هم چنین شناسایی دو ژنوتیپ کم خطر 6 و 53 در ضایعات بافتی میتواند نشان دهنده اهمیت ژنوتیپ های کم خطر در برنامه های پیشگیری و غربالگری سرطان دهانه رحم باشد.

    کلید واژگان: اگزوتوکسین A, پروبیوتیک ها, سودوموناس آئروژینوزا, ساکارومایسس سرویزیه}
    Zahra Ghorbani, Maryam Koupaei, Horieh Saderi, Seyed Mahmoud Amin Marashi, Zahra Dehghanzadeh, Parviz Owlia*
    Background and Aim

     Pseudomonas aeruginosa is an important ubiquitous and especially common pathogen in the hospital. Exotoxin A that encoded by exoA gene has a role in pathogenesis of this bacterium. Today, probiotics are widely used in the treatment and prevention of diseases. The present study aimed to study the Saccharomyces cerevisiae S3 effect on the expression of exoA gene.

    Materials and Methods

     S. cerevisiae S3 supernatant and lysate were prepared. Subminimum inhibitory concentrations (sub-MIC) of extracts were used to P. aeruginosa PAO1. The level of exoA expression was measured with real-time PCR method.

    Results

    Lysate extract had a reducing effect on toxin gene expression, but unlike lysate, supernatant had an increasing effect on gene expression.

    Conclusion

     We demonstrated that S. cerevisiae S3 had an inhibitory effect on Exotoxin A virulence factor of P. aeruginosa. We suggest doing more experiments on the effect of S. cerevisiae on other virulence factors of P. aeruginosa and pathogens.

    Keywords: Exotoxin A, Probiotics, Pseudomonas aeruginosa, Saccharomyces cerevisiae}
  • Sara Sadeqi, Slawomir Michniewski, Farhad Nikkhahi, Eleanor Jameson, Seyed Mahmoud Amin Marashi
    Background and Objectives

    Klebsiella pneumoniae is a clinically relevant opportunistic pathogen belonging to the Enterobacteriaceae family. It is in the top three bacteria associated with antimicrobial resistance deaths globally, and one of the most dangerous bacteria causing nosocomial infections. Phage therapy offers a potential option for the treatment of drug-resistant bacterial infections.

    Materials and Methods

    Phage PSKP16 was isolated against K. pneumoniae, capsular type K2 (isolated from a wound infection). PSKP16 is a new lytic phage with a Siphovirus-like morphology.

    Results

    PSKP16 is a linear double stranded DNA phage with a GC content of 50% and genome size of 46,712 bp, for which we predicted 67 ORFs. PSKP16 belongs to the genus Webervirus and shows high evolutionary proximity to Klebsiella phages JY917, Sushi, and B1.

    Conclusion

    Phage isolation is fast, cheap and efficient, but it requires time and characterization (which adds expense) to ensure that the isolated phages do not pose a health risk, which is essential to safely use phage therapy to treat life-threatening bacterial infections.

    Keywords: Klebsiella pneumoniae, Bacteriophages, Drug resistance, Infection control, High throughput nucleotide sequencing}
  • Neda Hajihassani, Orkideh Alavi, Mohamadjavad Karamshahi, Seyed MahmoudAmin Marashi, Abbasali Khademi
    Background

    A new method to improve the properties of the materials is nano‑encapsulation, which improves the biological properties, antibacterial activity along with reduction of toxicity. Due to the spread of nano‑knowledge, the present study was performed to evaluate the antibacterial effect of nano‑chlorhexidine (CHX) on Enterococcus faecalis biofilm in the root canal system.

    Materials and Methods

    In this in vitro experimental study, 55 matured single‑root mandibular premolars were decoronated and the canals were prepared by single length method up to #F3 ProTaper Universal system. Five teeth were selected as negative control. Then, the teeth were randomly divided into three experimental groups (n = 15) and a positive control group (n = 5). The experimental groups were irrigated with 2% nano‑ CHX gel, 2% CHX solution, and 5.25% sodium hypochlorite (NaOCl), respectively. Finally, the number of colonies was counted. Kruskal–Wallis test was used to compare the number of colonies among groups. The level of significance was set at P < 0.05.

    Results

    The mean number of colonies in the groups of nano‑CHX, NaOCl, CHX, and positive control were obtained as 17.73 ± 18.69, 35.53 ± 36.42, 38.8 ± 31.8, and 96.8 ± 22.52, respectively. There was a significant decrease in the number of colonies in all the experimental groups compared to the control group (P < 0.05). However, difference in the number of colonies among these three groups was not significant (P > 0.05).

    Conclusion

    The use of nano‑CHX in removing E. faecalis biofilm from root canal is as effective as the use of CHX and NaOCl.

    Keywords: Chlorhexidine, Enterococcus faecalis, nanoparticles, sodium hypochlorite}
  • Neda Hajihassani, Orkideh Alavi, Mohamadjavad Karamshahi, Seyed Mahmoud Amin Marashi, Abbasali Khademi
    Background

    A new method to improve the properties of the materials is nano‑encapsulation, which improves the biological properties, antibacterial activity along with reduction of toxicity. Due to the spread of nano‑knowledge, the present study was performed to evaluate the antibacterial effect of nano‑chlorhexidine (CHX) on Enterococcus faecalis biofilm in the root canal system.

    Materials and Methods

    In this in vitro experimental study, 55 matured single‑root mandibular premolars were decoronated and the canals were prepared by single length method up to #F3 ProTaper Universal system. Five teeth were selected as negative control. Then, the teeth were randomly divided into three experimental groups (n = 15) and a positive control group (n = 5). The experimental groups were irrigated with 2% nano‑ CHX gel, 2% CHX solution, and 5.25% sodium hypochlorite (NaOCl), respectively. Finally, the number of colonies was counted. Kruskal–Wallis test was used to compare the number of colonies among groups. The level of significance was set at P < 0.05.

    Results

    The mean number of colonies in the groups of nano‑CHX, NaOCl, CHX, and positive control were obtained as 17.73 ± 18.69, 35.53 ± 36.42, 38.8 ± 31.8, and 96.8 ± 22.52, respectively. There was a significant decrease in the number of colonies in all the experimental groups compared to the control group (P < 0.05). However, difference in the number of colonies among these three groups was not significant (P > 0.05).

    Conclusion

    The use of nano‑CHX in removing E. faecalis biofilm from root canal is as effective as the use of CHX and NaOCl.

    Keywords: Chlorhexidine, Enterococcus faecalis, nanoparticles, sodium hypochlorite}
  • Sareh Habibzadeh, Solmauz Eskandarion, Seyed MahmoudAmin Marashi, Ghazal Yunesi, Mohamadjavad Kharazifard
    Objectives

    This study aimed to evaluate the in vitro antifungal efficacy of addition of silver nanoparticles (SNPs) to Mucopren® silicone soft liner material.

    Materials and Methods

    Twenty disc samples (8 × 2 mm) of Mucopren® silicone soft liner containing 0wt% (control), 0.5wt%, 1wt%, 2wt%, and 3wt% SNPs were fabricated. Samples were powdered and added to 150 mL of Sabouraud dextrose agar culture medium and placed on separate culture dish plates. Each plate was inoculated with 106 colony forming units per milliliter (CFUs/mL) of Candida albicans (PTCC 5027) according to the CLSI protocol, and incubated at 37℃. The colony count was verified at 24 h, and the antifungal effect of the samples was evaluated according to the percentage of viable cells in the 2 subgroups with/without thermocycling. Data were analyzed using SPSS version 20 via ANOVA and t-test (P<0.05).

    Results

    All experimental groups showed higher antifungal activity than the control group, and this effect was dose-dependent (P<0.05). The lowest colony count was recorded in the 3wt% group. Thermocycling had no significant effect on the antifungal efficacy, except in 0.5wt% concentration of SNPs (P=0.013).

    Conclusion

    Addition of SNPs to Mucopren soft liner conferred antifungal effects. Further mechanical stability and toxicity studies are still required.

    Keywords: Antifungal Agents, Candida albicans, Denture Liners, Stomatitis, Denture, Nanoparticles}
  • Nastaran Hemmati, Farhad Nikkhahi, Amir Javadi, Sahar Eskandarion, Seyed MahmoudAmin Marashi
    Background and Objectives

    Neisseria meningitidis, Escherichia coli K1, Streptococcus agalactiae, and Streptococcus pneumoniae cause 90% of bacterial meningitis. Almost all infected people die or have irreversible neurological complications. Therefore, it is essential to have a diagnostic kit with the ability to quickly detect these fatal infections.

    Materials and Methods

    The project involved 212 patients from whom cerebrospinal fluid samples were obtained. After total genome extraction and performing multiplex quantitative polymerase chain reaction (qPCR), the presence or absence of each infectious factor was determined by comparing with standard strains.

    Results

    The specificity, sensitivity, positive predictive value, and negative predictive value calculated were 100%, 92.9%, 50%, and 100%, respectively. So, due to the high specificity and sensitivity of the designed primers, they can be used instead of bacterial culture that takes at least 24 to 48 hours.

    Conclusion

    The remarkable benefit of this method is associated with the speed (up to 3 hours) at which the procedure could be completed. It is also worth noting that this method can reduce the personnel unintentional errors which may occur in the laboratory. On the other hand, as this method simultaneously identifies four common factors that cause bacterial meningitis, it could be used as an auxiliary method diagnostic technique in laboratories particularly in cases of emergency medicine.

    Keywords: Cerebrospinal fluid, Meningitis, Quantitative polymerase chain reaction, Simultaneous detection, Diagnosistesting}
  • Sara Sadeqi, Parvin Heidariyeh, Mostafa Qorbani, Farhad Nikkhahi, Seyed Mahmoud Amin Marashi*
    Aims

    Foodborne infections caused by bacteria, including Salmonella enteritidis, Shigella flexneri, and Escherichia coli O157:H7 are one of the most common diseases among poultry and humans. The purpose of this study was the simultaneous and rapid detection of important microorganisms found in fecal samples of poultry and poultry workers.

    Materials & Methods

    A total of 144 fecal samples were taken from poultry and poultry farms workers. Fecal swabs were cultured on specific media, and biochemical tests were performed for further confirmation of bacterial isolates. Moreover, genomic DNA of fecal swabs was extracted for molecular identification of S. enteritidis, E. coli O157: H7, and S. flexneri species using multiplex-PCR technique.

    Findings

    According to the multiplex-PCR technique results, 16.7, 13.9, and 9.5% of the poultry samples were positive for the presence of S. enteritidis, E. coli O157: H7, and S. flexneri species, respectively; whereas culture method results showed the corresponding prevalence rates of 18.1, 15.2, and 12.5% for the above species. Moreover, regarding the samples collected from the poultry farms workers, multiplex PCR showed the prevalence rates of 6.9, 12.5, and 4.2% for S. enteritidis, E. coli O157: H7 , and S. flexneri species, respectively; whereas culture method showed the corresponding prevalence rates of 8.3, 13.9, and 13.9% for the above species.

    Conclusion

    In the current study, the sensitivity and specificity of multiplex-PCR in detecting S. enteritidis, E. coli O157: H7, and S. flexneri species were 74 and 100% for samples taken from the poultry farms workers, and 82.2 and 100% for samples taken from the poultry, respectively, suggesting the possibility of using a designed multiplex-PCR method for rapid detection of infectious agents in poultry farms.

    Keywords: Salmonella enteritidis, Shigella flexneri, Escherichia coli, Muliplex-PCR, Poultry}
  • Navid Saidi, Parviz Owlia, Seyed Mahmoud Amin Marashi, Horieh Saderi*
    Background and Objectives
    Staphylococcus aureus, as an opportunistic pathogen, is the cause of a variety of diseases from mild skin infections to severe invasive infections and food poisoning. Increasing antibiotic resistance in S. aureus isolates has become a major threat to public health. The use of compounds produced by probiotics can be a solution to this problem. Thus, the purpose of this study was to investigate the effect of Saccharomyces cerevisiae on some virulence factors (biofilm, α-hemolysin, and enterotoxin A) of S. aureus.
    Materials and Methods
    Supernatant and lysate extracts were prepared from S. cerevisiae S3 culture. Sub-MIC concentrations of both extracts were separately applied to S. aureus ATCC 29213 (methicillin-sensitive S. aureus; MSSA) and S. aureus ATCC 33591 (methicillin-resistant S. aureus; MRSA) strains. Biofilm formation of these strains was measured by microtiter plate assay and expression level of α-hemolysin and enterotoxin A genes (hla and sea, respectively) using real-time PCR technique.
    Results
    The supernatant extract has reduced both biofilm formation and expression of sea and hla genes, while lysate extract had only anti-biofilm effects. The MRSA strain showed more susceptibility to yeast extracts than MSSA strain in all tests.


    Conclusion
    The present study exhibited favorable antagonistic effects of S. cerevisiae S3, as a probiotic yeast, on MSSA and MRSA strains. Based on the findings of this study, the compounds produced by this yeast can be used to control S. aureus infections; however, further similar studies should be conducted to confirm the findings of the present study.
    Keywords: Biofilm, Exotoxins, Probiotic, Saccharomyces cerevisiae, Staphylococcus aureus}
  • سمیه خرمیان طوسی*، احمد جعفری، سیدمحمود امین مرعشی، سالومه فرامرزی نیکنام، ملیحه فرید
    مقدمه
    در مطالعات متعددی اثر ضدباکتری عصاره گیاه کلپوره (Teucrium polium) گزارش شده است. هدف از تحقیق حاضر، تعیین اثر آدامس حاوی عصاره آبی گیاه دارویی کلپوره بر تعداد استرپتوکوک موتانس بزاق بود.
    مواد و روش ها
    در این کارآزمایی بالینی دوسویه کور، تعداد 20 دانشجوی دندانپزشکی به طور تصادفی به دو گروه تقسیم شدند. گروه اول، آدامس حاوی عصاره آبی گیاه کلپوره دریافت نمودند. گروه دوم، آدامس بدون عصاره گیاه کلپوره دریافت نمودند. هر فرد به مدت سه هفته و هر روز سه بار بعد از هر وعده غذایی، آدامسها را به مدت 20 دقیقه استفاده کردند. نمونه بزاق غیر تحریکی افراد در شروع آزمایش و قبل از مصرف آدامسها و یک روز پس از مصرف آدامس نهایی و اتمام دوره جمع آوری شد. برای تعیین میزان باکتری از روش qPCR استفاده شد. مقایسه میزان کلونیزاسیون استرپتوکوک موتانس بین گروه ها با استفاده از آزمون T و نرم افزار SPSS نسخه 21 انجام گرفت.(05/0= α)
    یافته ها
    دو گروه مورد بررسی از نظر تعداد کلونی های استرپتوکوک موتانس قبل از مصرف آدامس اختلاف آماری معنی داری با یکدیگر نداشتند (05/0P>). مصرف آدامس حاوی کلپوره در مقایسه با آدامس دارونما به طور معنی داری باعث کاهش تعداد کلونی های استرپتوکوک موتانس گردید (002/0=P).
    نتیجه گیری
    نتایج حاصل از این تحقیق نشان داد که آدامس حاوی عصاره آبی کلپوره میزان کلونیزاسیون استرپتوکوک موتانس را در بزاق انسان به طور قابل توجهی کاهش داد.
    کلید واژگان: آدامس, استرپتوکوک موتانس, بزاق, عصاره کلپوره}
    Somayeh Khoramian Tusi *, Ahmad Jafari, Seyed Mahmoud Amin Marashi, Salomeh Faramarzi Niknam, Malihe Farid
    Introduction
    Several studies have reported the antibacterial effect of Teucrium polium extract. In this study, we sought to determine the effect of a chewing gum containing the aqueous extract of Teucrium polium on the level of salivary Streptococcus mutans.
    Materials And Methods
    In this double-blind clinical trial, 20 dental students were randomly assigned to two groups of intervention and control. The intervention group received a chewing gum containing the aqueous extract of Teucrium polium, and the control group received a chewing gum without any plant extract. Each person chewed the gum for 20 minutes three times a day (after each meal) for three weeks. Unstimulated saliva samples were collected at the beginning of the experiment before the use of the gums and one day after the final gum consumption. The quantitative polymerase chain reaction (qPCR) technique was employed to determine the bacterial level. The colonization rate of Streptococcus mutans was compared between the two groups by using t-test in SPSS, version 21.
    Results
    There was no significant difference between the two groups in terms of Streptococcus mutans counts before the intervention (P>0.05). The consumption of Teucrium polium extract-containing chewing gum in comparison with the placebo gum significantly diminished the number of Streptococcus mutans colonies (P=0.002).
    Conclusion
    The results of this study showed that the chewing gum containing the aqueous extract of Teucrium polium significantly lowered the colonization rate of Streptococcus mutans in human saliva.
    Keywords: Chewing gum, Streptococcus mutans, Salvia, Teucrium polium extract}
  • Fariba Asgharpour, Seyed Mahmoud Amin Marashi, Zahra Moulana
    Background And Objectives
    Multidrug resistant Salmonella strains have been observed around the world in recent years. Many mechanisms contribute to the spread of antimicrobial resistance genes. This study aimed at determining the distribution and transmission of class 1, 2 and 3 integrons among MDR Salmonella isolates collected from a selection of chicken broilers in the north of Iran.
    Materials And Methods
    PCR assays were used to detect genes for tetracyclines (tetA, tetB and tetG), chloramphenicol (cat1 and floR), and streptomycin (strA). Also, the presence of class 1, 2 and 3 integrons in all MDR isolates was evaluated using specific primers for the integrase genes of integrons intI1, intI2 and intI3.
    Results
    Class 1, 2 and 3 integrons were present in 36%, 42% and 4% of the MDR isolates, respectively. Out of the tetracyclines resistant isolates, 47 (100%) and 5 (10.6%) carried tetA, tetB genes, respectively, while no isolate was positive for the tetG gene. All 36 chloramphenicol- resistant strains carried floR and cat1 genes. Nine (18%) Salmonella Infantis isolates harbored the strA gene, conferring resistance to sterptomycin.
    Conclusion
    This study found a high frequency of antimicrobial resistance genes among Salmonella isolates; therefore, management strategies are needed to prevent food-borne diseases caused by MDR Salmonella from food supplies.
    Keywords: Integrons, Salmonella infantis, Multidrug resistance, Poultry}
  • Farhad Shafiei *, Arezoo Ashnagar, Mehrsima Ghavami-Lahiji, Farhood Najafi, Seyed Mahmoud Amin Marashi
    Statement of problem: Secondary dental caries is a common clinical finding in composite restoration. The development of a bactericidal dental adhesive provides a promising method to reduce the risk of secondary caries.
    Objectives
    This study aimed to assess the antibacterial activity of silver (Ag) and titanium dioxide (TiO2) nanoparticles incorporated into an experimental dentin bonding agent formulation.
    Materials And Methods
    Ag and TiO2 nanoparticles at 0.05, 0.1, 0.2, 0.5, and 1 wt% concentrations were incorporated into the adhesives. The suspensions were sonicated to ensure homogenous dispersion of nanoparticles in the adhesive system. Formulation was composed of acetone, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane (Bis-GMA), 1,6-bis-[2-methacryloyloxyethyl carbonyl amino]-2,4,4-trimethylhexane (UDMA), trimethylolpropane trimethacrylate (TMPTMA), 2-hydroxyethyl methacrylate (HEMA), and photoinitiator, with polyvinylpyrrolidone (PVP) as the stabilizer. We counted the colony-forming units (CFU%) of two cariogenic bacteria, Streptococcus mutans (S. mutans) and Lactobacillus acidophilus (L. acidophilus), that were exposed to the powdered light cured adhesive specimens. The effects of various concentrations of each nanoparticle were compared by one-way ANOVA, followed by the post hoc Bonferroni test.
    Results
    All samples exhibited definite antibacterial activity (P
    Conclusions
    These metal-based nanoparticles exhibited dose-dependent bactericidal activities. The Ag nanoparticles had higher antibacterial activity compared to the TiO2 nanoparticles. Incorporation of these nanoparticles into dental adhesives is a promising way to reduce the risk of secondary caries. However, further clinical evaluations should be performed.
    Keywords: Dental adhesive, Nanoparticle, Antibacterial, Silver, Titanium dioxide}
  • نوید سعیدی، پرویز اولیا، سیدمحمود امین مرعشی، حوریه صادری
    مقدمه و هدف
    تولید بیوفیلم یک فاکتور بیماری زایی مهم در استافیلوکوکوس اورئوس است. اغلب عفونت های مرتبط با بیوفیلم این باکتری به سختی با آنتی بیوتیک ها درمان می شود. تا به حال مکانیسم های زیادی برای عملکرد مخمرهای پروبیوتیکی در مقابل عفونت های باکتریایی توضیح داده شده اما مطالعات کمی در زمینه تاثیر آن ها بر تشکیل بیوفیلم انجام شده است. هدف از این تحقیق بررسی اثر مخمر ساکارومایسس سرویزیه بر تشکیل بیوفیلم استافیلوکوکوس اورئوس بود.
    مواد و روش ها
    از کشت ساکارومایسس سرویزیه عصاره سوپرناتانت و لیزات تهیه شد. پس از تعیین MIC، تاثیر عصاره ها با سه غلظت μg/ml 512، 1024 و 2048 بر تشکیل بیوفیلم دوسویه استاندارد باکتری استافیلوکوکوس اورئوس ATCC 29213 (حساس به متی سیلین) و ATCC 33591 (مقاوم به متی سیلین) به روش میکروتیتر پلیت با سه بار تکرار مورد ارزیابی قرار گرفت.
    نتایج
    هر دو عصاره سوپرناتانت و لیزات مخمر توانستند در تمامی غلظت ها تشکیل بیوفیلم دوسویه حساس و مقاوم به متی سیلین استافیلوکوکوس اورئوس را به طور معنی داری کاهش دهند (P<0.001). درحالی که هر دوسویه مورد مطالعه تولیدکننده بیوفیلم قوی بودند، غلظت μg/ml 2048 سوپرناتانت توانست تشکیل بیوفیلم آن ها را به درجه متوسط کاهش دهد. همچنین لیزات به طور موثرتری موجب کاهش تشکیل بیوفیلم به درجه ضعیف شد.
    نتیجه گیری
    در این مطالعه برای اولین بار اثر مطلوب مخمر ساکارومایسس سرویزیه بر کاهش تشکیل بیوفیلم استافیلوکوکوس اورئوس مشاهده شد. با انجام مطالعات بیشتر می توان به درمان عفونت های ناشی از بیوفیلم این باکتری با استفاده از مخمرهای پروبیوتیکی امیدوار بود.
    کلید واژگان: استافیلوکوکوس اورئوس, بیوفیلم, پروبیوتیک, ساکارومایسس سرویزیه}
    Navid Saidi, Parviz Owlia, Seyed Mahmoud Amin Marashi, Horieh Saderi
    Background And Objective
    Biofilm formation is an important virulence factor in Staphylococcus aureus. Most infections associated with biofilm of this bacterium are difficult to treat with antibiotics. As yet, a lot of mechanisms have been explained for probiotic yeast functions against bacterial infections, but few studies have been done on their effects on biofilm formation. The aim of this study was to evaluate the effect of Saccharomyces cerevisiae yeast on Staphylococcus aureus biofilm formation.
    Materials And Methods
    Extract of supernatant and lysate was prepared from Saccharomyces cerevisiae culture. After determining the MIC, the effect of extracts at three concentrations of 2048, 1024 and 512 µg/ml was evaluated on biofilm formation of two standard strains of S. aureus, ATCC 29213 (methicillin-sensitive) and ATCC 33591 (methicillin-resistant) using the microtiter plate assay in three replications.
    Results
    Both supernatant and lysate extract of yeast could significantly reduce the biofilm formation of both methicillin-sensitive and resistant strains of S. aureus at all concentrations. While both studied strains were strong biofilm producers, at the concentration of 2048 µg/ml, supernatant could reduce their biofilm formation to moderate level. Also, lysate reduced biofilm formation to weak level more effectively.
    Conclusion
    In this study, the good effect of S. cerevisiae yeast on the reduction of S. aureus biofilm formation was observed for the first time. Doing more studies, it is expected to treat infections caused by biofilm of this bacterium with probiotic yeasts.
    Keywords: Staphylococcus aureus, Biofilm, Probiotic, Saccharomyces cerevisiae}
  • Enayatollah Kalantar, Majid Madani, Amir Hatami, Mohammad Hossein Dehghan, Monireh Ebadi, Morteza Nazari, Saber Saifei, Seyed Mahmoud Amin Marashi *
    Multidrug resistance in Acinetobacter baumannii is a growing public health concern all over the world. In the current study, the isolation and antimicrobial resistance pattern and detection of blaOXA-51 and lpxC genes by multiplex PCR method was performed.
    All the isolates demonstrated high levels of resistance rates to amikacin, ciprofloxacin, meropenem, imipenem, ceftriaxone, gentamicin, and colistin. Screening of two resistance genes by multiplex PCR showed that all the isolates contained blaOXA-51 and lpxC genes. As we previously reported, nosocomial infections caused by A. baumannii isolates are a major cause of morbidity and mortality in our hospital.
    Keywords: Acinetobacter baumannii, nosocomial infection, multidrug, resistance, blaOXA-51, lpxC genes}
  • Mohammad Hadi Naseh, Seyed Mahmoud Amin Marashi, Esfandiar Asgari, Maryam Aghabarari, Ellaheh Mahmudi, Mozhan Asadi, Shiva Hatami, Enayatollah Kalantar *
    Background
    Bacteremia is a frequent condition in cancer patients with a significant morbidity and mortality worldwide, which is a medical crisis that needs broad-spectrum antibiotic treatment..
    Objectives
    This study examined bacteremia in cancer patients from two medical centers regarding isolates and spectrum of antibiotic resistance pattern..Patients and
    Methods
    This was a prospective experimental investigation performed in Tehran and Karaj Cities, Iran. From the blood culture bottles, isolation and identification of the bacteria were performed by conventional microbiological techniques. In vitro antibiotic resistance pattern of the isolates was determined by CLSI guidelines. Genomic DNA was isolated by DNA extraction kit. Each gene was separated by agar gel electrophoresis..
    Results
    In total, 68 blood culture bottles were received from cancer patients, from which 12 (17.65%) samples had positive results. The most common bacterial pathogen isolated was E. coli, accounting for 5 (33.33%). While each of S. aureus, B. cereus and K. pneumonia accounted for 3 (20%) samples. Penicillin, ampicillin, gentamicin, cefoxitin, trimethoprim sulfamethoxazole and tetracycline were the most resistant antibiotics with 100% resistance to the tested E. coli isolates. Similarly, S. aureus was 100% resistant to gentamicin and sulfamethoxazole. Identification of the 88 bp phoA gene in E. coli isolates was 100%. Similarly, the 310 bp mecA fragment was obtained from all of the resistant S. aureus isolates after DNA amplification..
    Conclusions
    All the bacterial isolates were associated with a high resistance to various antibiotics and this resistant pattern could be confirmed by detection of a particular gene for each bacterium..
    Keywords: Blood, Bacteremia, Multiplex Polymerase Chain Reaction, Escherichia coli}
  • Sedigheh Ebrahimi Kasgari, Mahnaz Nourani, Yousef Yahyapour, Seyed Ehsanollah Mousavi, Enayatollah Kalantar, Hami Kaboosi, Seyed Mahmoud Amin Marashi *
    Background
    Cholera is one of the most diseases of human. Cholera toxin is the most important pathogenic factor in humans that causes diarrhea. The cholera toxin is produced by V. cholerae and CTXфPhage..
    Objectives
    In this study, we have investigated the production cholera toxin with different density of Vibrio cholerae..
    Materials And Methods
    With this propose we inoculated classical strain O1 of Vibrio cholerae ATCC 14035 and Vibrio cholerae O1biovar El Tor N16961 into the AKI medium. Then, the total mRNA was determined by standard procedure which was converted into total cDNA..
    Results
    Cholra toxin production was determined by qPCR and maximum production of cholera toxin was at 1010 cfu/mL..
    Conclusions
    In conclusion, production of cholera toxin was minimized almost up to zero at 1010.5 cfu/mL; which could be due to presence of high level concentration of autoinducer..
    Keywords: Vibrio cholerae, Cholera Toxin, Populations}
  • Somaye Yasliani Fard *, Seyed Mahmoud Amin Marashi, Sahar Yasliani Fard, Mehdi Mirzaii, Seyed Ehsan Moosavi
    Background
    plants been used for biological basis of drug substances in thousand years. Some of the plants have inhibitory effects on growth of intestinal infections. Black pepper is the plant that uses as classical medicine in the infections. Vibrio cholerae and Staphylococous aureus are two important bacterial agents in the food contamination..
    Objectives
    In this study, inhibitory effects of (watery_alcoholic) extractions and essence of black pepper were studied against S. aureus and V. cholerea..
    Materials And Methods
    Extraction produced by soaking method then for determined antibacterial effects were used cylinder method. For preparation essence 50 gram of powdered black pepper was extracted by soaking, ethod and effect of essence was studied against the target cultuer by using the cup diffusion method. We also determined the MIC and MBC by micro dilution method..
    Results
    Essence of black pepper showed good antibacterial effect on this bacteria. MIC of essence on the V. cholerea and S. aureus was 38 µg/mL and 75 µg/mL, but alcohol and watery extractions didn’t have antibacterial effect on these bacteria..
    Conclusions
    essence of black pepper showed a potent antibacterial activity and therefore, it may be used as an inhibitory extract against S. aureus and V. cholerea in food industry..
    Keywords: Black Pepper, Staphylococcus aureus, Vibrio cholerae}
  • Enayatollah Kalantar, Jafar Soltani, Shiva Hatami, Nooshin Habibi, Helen Pormazaheri, Seyed Mahmoud Amin Marashi, Khatereh Amini, Afshin Afshar, Kurosh Kabir, Ali Akabr Safari *
    Background
    Foodborne illnesses continue to be a leading cause of morbidity and mortality worldwide; however, the burden of diseases caused by food-borne pathogens remains largely unknown..
    Objectives
    The aim of the present study was to culture-confirmed the bacterial profile and their antibiotic resistant pattern in Food and Drug Laboratory, Alborz University of Medical Sciences, Karaj, Iran..Patients and
    Methods
    A total of 22 bacteria including of Staphylococcus aureus, Klebsiella spp and E. coli were presumptive isolated from the traditional ice cream, cream pastries, sausage, and salami by the Official Food Microbiology Laboratory, Deputy of Food and Drug Administration, Alborz University of Medical Sciences, Karaj, Iran, and sent to the Research Center Laboratory, Alborz University of Medical Sciences, to confirm the bacterial spp by multiplex polymerase chain reaction. These isolates were also checked for their antimicrobial resistance pattern according to CLSI guideline..
    Results
    The highest rate of contamination was with Klebsiella spp 09 (40.9%), followed by S. aureus 07 (31.8%), E. coli 06 (27.27%), as reported by the Official Food Microbiology Laboratory of Alborz University of Medical Sciences. Gel electrophoresis of the isolates shows the 600bp bp and 80 bp gene among S. aureus and E. coli respectively. The antibiotic resistant pattern in case of Klensiella spp showed that 6 (66.6%) Klensiella spp were resistant to Penicillin and Cotrimoxazole. Similarly, penicillin and amoxicillin were found the highest resistant antibiotic against 83.3% E. coli, however, ceftriaxone showed the highest sensitivity against 100% E. coli isolates..
    Conclusions
    In conclusion, Klebsiella spp, S. aureus and E. coli are contaminants of food specimens obtained from food industries in Karaj, Iran; they constitute a serious health risk for human population. Moreover, the principal purpose of this study is to increase awareness of the antibiotic resistance of these bacteria poses threat..
    Keywords: Antibiotic Resistance, Klebsiella, Staphylococcus aureus, E. coli}
  • Narges Rahimi, Mahnaz Nourani, Yousef Yahyapour, Enayatollah Kalantar, Sommayeh Yasliyanifard, Seyed Mahmoud Amin Marashi *
    Background
    Cholera is a severe disease which is caused by Vibrio cholerae and it is typically transmitted by either contaminated food or water particularly in developing countries. The most important virulence factor of this bacterium is an enterotoxin called cholera toxin which is a protein complex secreted by the Vibrio cholerae..
    Objectives
    In this project, we determined the production of cholera toxin at different pH values..
    Materials And Methods
    Two standard strain of Vibrio cholerae O1 biovar EL Tor N16961 and Vibrio cholerae O1 biovar Classic ATCC 14035 were used. After overnight cultivation of both the strains the total mRNA extracted and converted to total cDNA..
    Results
    By Relative Real-Time PCR analysis the most cholera toxin production in classical and El Tor strains was at pH 8.5 and 8, respectively..
    Conclusions
    Therefore, We may conclude that use of acidic diet will help in reduction of cholera toxin production..
    Keywords: Vibrio cholerae, Cholera Toxin, Enterotoxin}
  • Enayatollah Kalantar, Maryam Aghabarari, Esfandiar Asgari, Mojan Assadi, Seyed Mahmoud Amin Marashi, Shiva Hatami, Alireza Shakib *
    Background
    Symptomatic bacteraemia, is a frequent condition among cancer patients with a significant morbidity and mortality all over the world..
    Objectives
    The aim of this study was to determine the burden of enteric pathogens causing bacteremia among cancer patients..Patients and
    Methods
    Ten ml blood samples were withdrawn from the cancer patients under aseptic conditions. The blood specimens were added to the blood culture bottles and incubated at 37°C. The bacterial isolates from these samples were identified by routine biochemical reactions..
    Results
    During the study period, 68 blood samples from cancer patients were analyzed for bacteremia. Of these patients, six were female (08/82%) and 62 were male (91.18%); with age ranging from under 40 years to 85 years old (mean, 63 years). Gastro-intestinal cancer and cancers of head and neck were the most frequent cancer types in the studied group, accounting for 51 (75%) and 15 (22.1%) cases, respectively. The mean weight of patients was 69.18 Kg (range: 49-100 Kg). Similarly, the mean length of hospital stay was 8 days (range: 4-12 days). Positive blood cultures were detected in only 12 (17.65%) and 11 (91.7%) blood specimens from the Cancer Institute, Tehran, compared with one (08.33%) from Shahid Kamali hospital, Karaj. From these patients, 15 bacteria were isolated; E. coli alone outnumbered other species and accounted for 33.33% of the episodes of bacteremia..
    Conclusions
    In conclusion, our investigation revealed that cancers of GI tract are the most common cancer types causing bacteremia and also we identified that most common bacteria causing bacteremia in Cancer Institute, Tehran and Shahid Kamali Hospital, Karaj, are E. coli and S. aureus.
    Keywords: Bacteremia, Escherichia coli, Staphylococcus aureus}
  • Seyed Mahmoud Amin Marashi, Zahra Moulana, Abbas Ali Imani Fooladi *, Mohammad Mashhadi Karim
    Background

    For a long time, infertility has been one of the most sequels in medical sciences with microbial agents as one group of its causes. The possible etiological role of Chlamydia trachomatis in infertility was suggested years ago, but it has not yet been proved completely. To decrease the severe involvements of C. trachomatis infections, screening by efficient diagnostic methods are necessary.

    Objectives

    In this study we attempted to determine the incidence of C. trachomatis in infertile women and compared this with healthy women.

    Materials And Methods

    This case-control study was performed on 150 infertile women with unknown causes and without physiological deficiency for infertility. The control group consisted of 200 fertile safe and impregnated women. Presence of C. trachomatis in the two groups was examined by direct and indirect immunofluorescence tests and PCR.

    Results

    C. trachomatis was detected by direct immunofluorescence method in 23 (15.3%) infertile women compared and 7 (3.5%) healthy controls. Using indirect immunofluorescence tests, a positive test titer of 1:16 as well as the above results were detected in 34 (22.6%) of the infertile cases and 9 (4.5%) of the controls. C. trachomatis was detected by PCR method in 48 (32%) infertile women and 13 (8.7%) among the controls.

    Conclusions

    The results of our study suggest that there is a significant association between C. trachomatis infection and female infertility.

    Keywords: Chlamydia trachomatis, Infertility, Women, Iran}
  • Seyed Mahmoud Amin Marashi, Ramazan Rajabnia, Abbas Ali Imani Fooladi, Zohreh Hojati, Sharareh Moghim, Bahram Nasr Esfahani
    Cholera is an infection of the small intestines caused by the bacterium V. cholerae. It is a major cause of health threat and also a major cause of death worldwide and especially in developing countries. The major virulence factor produced by V. cholerae during infection is the cholera toxin. Total mRNA extraction and reverse transcription was performed for making ctxAB cDNA. Relative Real-Time PCR analysis showed unequal enterotoxin production in V. cholerae strains. The results showed that, classical strain produces cholera toxin more than El Tor strain.
    Keywords: Vibrio cholerae, RT, qPCR, ctxAB expression}
  • Seyed Mahmoud Amin Marashi, Bahram Nasr Esfahani, Akbar Tavakoli, Sharareh Moghim, Mohammad Reza Pourshafie, Mansoor Salehi
    Objective(s)Amongst the various antibiotic resistant elements in Vibrio. cholerae, SXT constin (SXT-C) is important. We were going to design a quick method for determination of antibiotic resistance gene pattern in SXT-C.Materials and MethodsNinety fourV. cholerae O1El Tor isolates were used in this study. Antibiotic susceptibility testing, multiplex PCR amplification of SXT-C containing dfrA1, sulII, strB and the int in a multiplex PCR were done. ResultsResults of our study showed that 92 (97.8%) out of 94 isolates were positive for all above genes. Multiplex PCR results correlated with the antibiotic susceptibility data obtained by using disc diffusion assay.ConclusionUsing this multiplex PCR, it would be easily possible to demonstrate the presence of antibiotic resistance in SXT-C which, in turn, allows for a suitable treatment in cholera patients causing reduction in the mortality and morbidity rate of the infected individuals.
سامانه نویسندگان
  • دکتر سید محمود امین مرعشی
    امین مرعشی، سید محمود
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