فهرست مطالب

Medical Bacteriology - Volume:5 Issue: 3, 2016
  • Volume:5 Issue: 3, 2016
  • تاریخ انتشار: 1395/06/18
  • تعداد عناوین: 8
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  • Samira Hosseini Hooshyar, Baharak Akhtardanesh, Saied Reza Nourollahi Fard, Mohammad Khalili Pages 1-8
    Background
    Feline haemotropic mycoplasma are a group of pleomorphic bacteria causing hemolytic anemia along with anorexia, lethargy, dehydration, weight loss and in many cases sudden death in infected animal. However, there is a limited data on the prevalence of these organisms in Iranian cats.
    Methods
    We investigated the presence of feline haemotropic mycoplasma and probable risk factors for these infections among 60 ectoparasite-infested stray cats in southeast of Iran using PCR assay.
    Results
    The overall prevalence of haemotropic mycoplasma was estimated 18.3%. Pallor mucous membrane, anorexia, weight loss and splenomegaly were the most common signs and the infection rate was significantly higher in symptomatic cats in comparison with apparently healthy ones (P = 0.001). Age, gender and hematological alterations were not significantly associated with infection status while the level of BUN, creatinine, total protein and globulin were significantly higher among infected animals.
    Conclusion
    The prevalence of feline hemoplasma infection in stray cats seems to be considerable in our study. More investigations are needed to obtain further information on epidemiological aspects of hemoplasmas in cats in Iran.
    Keywords: Haemotropic mycoplasma, Cat, PCR, Iran
  • Nafise Sadat Majidi, Giti Emtiazi, Samaneh Shahrokh Esfahani Pages 9-14
    Background
    Chitosan is unbranched polysaccharide composed of D-glucosamine and N-acetyl-D-glucosamine. Chitosan, derived from shrimp shell, has broad antimicrobial properties against Gram-negative, Gram-positive bacteria and fungi.
    Methods
    Chitosan was extracted from shrimp shell and studied for cell entrapment and anti-bacterial properties. The hydrogel chitosan was used as the beads for cell entrapment and chitosan beads were designed to deliver cells and nutrients. These data confirmed with flow cytometric analyses.
    Results
    Experimental results exhibited that internal diffusion through the chitosan matrix was the main mechanism for whole gelation by TPP (Tri-polyphosphate). The minimum inhibitory concentration (MIC) for chitosan against Staphylococcus aureus and Escherichia coli was 16 and 32 μg/ml respectively.
    Conclusion
    Despite the antimicrobial properties of chitosan, trapped bacteria in the gel network were alive and were chelated indicating that their access to the outside was limited.
    Keywords: Chitosan, Chitin, TPP, Antibacterial activity, Flow cytometry
  • Ali Asghar Ayatollahi, Abolfazl Amini, Reza Kazemi Darsanaki, Somayeh Rahimi Pages 15-21
    Background
    Nosocomial infections are considered as health issues that affect developed and poor countries. These infections can be transmitted to patients through hospital environment and equipments. The aim of this study was to evaluate the prevalence of Gram-negative bacilli in the environment and the equipments of hospitals in the East of Golestan province in 2015.
    Methods
    In this study, 770 samples were collected using sterile swabs from the environment and equipments which were in use in different units of six teaching hospitals located in the East of Golestan province. The collected samples were then identified by standard biochemical tests.
    Results
    Of the total samples, 249 samples (32.33%) were contaminated with Gram-negative bacilli with the most number of contaminations were Enterobacter aerogenes (37.75%) at the Department of Surgery (18.07%). Among the medical equipments and surfaces, the highest level of contamination was observed in laryngoscope and its blades (10.44%), suctions (7.23%), and EKG sensors and monitoring connectors (7.23%). Telephone handset (5.22%) and patients’ bed (5.22%) had the highest rate of contamination with Gram-negative bacilli in the non-medical equipments.
    Conclusion
    The results of the present study shows that Gram-negative bacilli contamination rates are considerable in hospitals in East of the Golestan province. Thus, hand washing, disinfecting, sterilizing medical equipment and generally compliance with the standards in this field are of great importance.
    Keywords: Gram, negative bacilli, Nosocomial infection, Hospital, environment equipments
  • Farkhondeh Saba, Moslem Papizadeh, Javad Khansha, Mahshid Sedghi, Mehrnoosh Rasooli, Mohammad Ali Amoozegar, Mohammad Reza Soudi, Seyed Abolhassan Shahzadeh Fazeli Pages 22-28
    Background
    Sequence-based identification of various microorganisms including Archaea, Bacteria, Cyanobacteria, Diatoms, Fungi, and green algae necessitates an efficient and reproducible genome extraction procedure though which a pure template DNA is yielded and it can be used in polymerase chain reactions (PCR). Considering the fact that DNA extraction from these microorganisms is time consuming and laborious, we developed and standardized a safe, rapid and inexpensive miniprep protocol.
    Methods
    According to our results, amplification of various genomic regions including SSU, LSU, ITS, β-tubulin, actin, RPB2, and EF-1 resulted in a reproducible and efficient DNA extraction from a wide range of microorganisms yielding adequate pure genomic material for reproducible PCR-amplifications.
    Results
    This method relies on a temporary shock of increased concentrations of detergent which can be applied concomitant with multiple freeze-thaws to yield sufficient amount of DNA for PCR amplification of multiple or single fragments(s) of the genome. As an advantage, the recipe seems very flexible, thus, various optional steps can be included depending on the samples used.
    Conclusion
    Having the needed flexibility in each step, this protocol is applicable on a very wide range of samples. Hence, various steps can be included depending on the desired quantity and quality.
    Keywords: Eukaryotes, Genome (DNA) extraction, Identification, Prokaryotes, Sequence
  • Shabnam Shamansouri, Vajihe Karbasizade Pages 29-33
    Background
    Staphylococcus epidermidis is an important agent for nosocomial infections in infants and people with permanent prostheses. Its increased resistance to antibiotics has created a serious challenge for healthcare system. This study was conducted to determine the pattern of antibiotic-resistance of S. epidermidis isolates from clinical samples.
    Methods
    During nine months, 251 clinical samples isolated from strains of S. epidermidis were examined. Following identification of isolates, their antibiotic sensitivity was determined using disc diffusion method. Resistance to vancomycin was assessed using agar screening method, and its MIC values were measured using episilometry (E-test). Methicillin-resistant gene (mecA) was traced using PCR.
    Results
    A total of 120 S. epidermidis strains were isolated from the 251 clinical samples, mostly associated with urine samples. In this study, 95 isolates (79%) were found resistant to cefoxitin, 66 (55%) to vancomycin, and 94 (78.33%) to multiple drugs. In molecular assessment, 37 isolates (54.41%) contained mecA gene, of which, 32 isolates showed resistance to vancomycin.
    Conclusion
    Increased resistance to methicillin and vancomycin in S. epidermidis isolates represents a serious warning to the healthcare system. Thus, careful and appropriate choice of treatment is imperative for reducing medication resistance.
    Keywords: Vancomycin, mecA, E Test, Staphylocossus epidermidis
  • Mohammad Amin Mashhady, Barat Ali Fakheri, Saeide Saeidi, Mehdi Hassanshahian, Javad Abkhoo Pages 34-37
    Background
    A large number of plants are used for treatment of diseases because of their antimicrobial activities. This study aims to investigate the antimicrobial effects of some plants on the food pathogenic bacteria.
    Methods
    Plant extracts were obtained using the rotary system, the minimum inhibitory concentration (MIC) by diluting method against bacteria was determined.
    Results
    Results showed that the lowest MIC of the Peganum harmala was 3.1 ppm and the highest inhibitory concentration was 6.25 ppm for inhibiting the Vibrio cholerae.
    Conclusion
    The present study confirms the use of this extract as an antibacterial agent. Further research is required to evaluate the practical value of its therapeutic application.
    Keywords: Antimicrobial activity, Food pathogen, Plant extract
  • Hossein Esmaeili, Hamideh Kalateh Rahmani Pages 38-41
    Background
    Salmonellosis is an infectious and a food-borne disease of humans and animals. The initial source of the infection is the intestinal tracts of birds and other animals. Apparently healthy animals can become subclinical carriers and persistently shed Salmonella in their feces which can act as a reservoir for the pathogen. The aim of this study is to detect the carriers of Salmonella among apparently healthy sheep and goat flocks of Bushehr and Lorestan provinces, Iran.
    Methods
    A total of 389 fecal samples were aseptically collected from the rectum of apparently healthy sheep and goat flocks of Bushehr and Lorestan provinces. Bacteriological culture was conducted using selenite cystine, Rappaport–Vassiliadis, brilliant green and xylose lysine deoxycholate agar. Suspected colonies were inoculated in to TSI, peptone water, Simmon’s Citrate, Urea medium and MRVP. Sero-groups were detected by antisera.
    Results
    Two samples from 189 samples (1.05%) were positive for Salmonella in Bushehr province. Salmonella abortusovis and Salmonella typhimurium were detected following serotyping. No Salmonella carriers were detected in Lorestan province.
    Conclusion
    As the rate of carriers of Salmonella was low, the risk of food-borne salmonellosis due to consumption of small ruminant's meat is low, especially in the condition of well cooked meat. Since S. abortusovis was detected, strategies of prevention and control of abortion due to this agent must be taken to reduce the economic losses. Moreover, the presence of S. typhimurium is a hazard to public health and people who have close contact to sheep and goats.
    Keywords: Bushehr, Iran, Lorestan, Salmonella, Small ruminant
  • Behzad Ghasemi, Hamid Beyzaei, Seyed Hadi Hashemi, Hamidreza Majidiani Page 50
    Introduction
    Escherichia coli is one of the important pathogens in human with global importance. Because of the necessity for identification and the use of novel antibacterial compounds against E. coli, in this present study we focused on the antibacterial effects of synthesized thiazole, imidazole and tetrahydropyridine derivatives on E. coli.
    Methods
    For evaluation of antibacterial effect, the disk diffusion method was applied to measure the growth inhibition zone diameter and broth micro-dilution was performed to determine the minimum inhibitory concentration (MIC).
    Results
    Assessing the antibacterial effect showed that only 6d derivative of thiazole had inhibitory effect on E. coli and the other thiazole, imidazole and tetrahydropyridine derivatives lacked any inhibitory result on this organism. The inhibitory effect of 6d derivative of thiazole was MIC=125 and growth inhibition zone diameter of 16±0.1.
    Discussion
    The antibacterial effect of thiazole, imidazole and tetrahydropyridine derivatives differs from each other and chemical linkages such as oxygen to thiazole ring in 6d derivative, could have reinforced this effect. The next step is determination of the toxicity and therapeutic effects in the laboratory animals.
    Keywords: Antibacterial effect, imidazole, thiazole, tetrahydropyridine, Escherichia col