دو ماهنامه میکروب شناسی پزشکی ایران
سال یازدهم شماره 5 (آذر و دی 1396)

Influenza A/H1N1, the cause of an acute respiratory illness, undergoes genetic changes every few years, resulting in a new subtype with new surface antigenic structure. The aim of this study was to investigate the prevalence of influenza A/H1N1 virus among specimens collected from patients with influenza symptoms who were admitted to educational and training hospitals in Guilan province, Iran.
This descriptive cross-sectional study was performed on upper respiratory tract discharges of patients with influenza symptoms in the counties of Guilan province, using Real-Time PCR technique in Gastrointestinal and Liver Diseases Research Center of Gilan University of Medical Sciences in 2015. The Fishers Exact Test or chi-square χ)2( was used for data analysis.
From 108 patients with influenza symptoms, 58 (53/7%) were female. The age range of patients was between 1-78 years old. The results showed that only 4 (3/7%) patients were positive for A/H1N1virus (3 male and 1 female). This included a male who was admitted with pneumonia and expired later.
Influenza virus A/H1N1 is a mutant virus, the genetic evolution in which is constantly occurring and new subtypes can, therefore, re-infect the community. It is thus imperative that vaccination is done to prevent against novel strains of influenza.

Infertility rate has increased by 50% during the last two decades in Iran. There are several factors affecting infertility among women and men, amongst which infections have gained a lot of attentions recently. Given the high percentage of infertility in Iran, the present study has aimed to investigate the prevalence of Chlamydia trachomatis, Mycoplasma genitalium and Neisseria gonorrhea amongst infertile women referring to a hospital in Tehran, Iran.
In the current descriptive study, 65 infertile women referring to Mahdieh Hospital in Tehran during 2016-2017 were included and two vaginal swabs and a questionnaire were taken for each patient. In the laboratory, DNA extraction using kit and PCR using specific primers were carried out.
Of the 65 vaginal swab specimens, 21 (32%) had bacterial infection and 44 (68%) had no bacterial infections, and 2 (3%) had the mixed infection. The prevalence of C. trachomatis, M. genitalium and N. gonorrhea were 9 (13.8%), 11 (16.9%) and 4 (6.2%) isolates, respectively. There was no relationship between history of abortion, use of oral contraceptive pills, education or age, with the prevalence of bacterial infections.
Based on the results of this study, M. genitalium, N.gonorrhea, and C.trachomatis were quite prevalent among infertile females and it can, therefore, be concluded that on-time control and treatment of infections caused by these organisms, together with other factors, could be important in prevention and treatment of women's infertility and the community’s health.

Listeria monocytogenes is one of the most important causes of abortion and postpartum infection in newborns. This study aimed to compare the indirect ELISA and immunofluorescence methods for the detection of anti-Listeria antibodies among women with spontaneous abortion.
In this study, indirect ELISA and immuno-fluorescence methods were used for the detection of anti-Listeria antibodies. Five milliliters of blood sample were collected from mothers with spontaneous abortion during the third trimester of pregnancy in a ward that examines the diseases of female genital tract in Kamali Hospital of Karaj, Iran. The samples were then transferred to the laboratory for examination using relevant kits. The serum titers of positive samples were also assessed via both ELISA and indirect immunofluorescence for evaluation of IgG and IgM antibodies. The antibodies titers were compared using SPSS software while P values From the 58 evaluated serum samples, 21 were positive for anti-Listeria antibody. Statistical analysis showed that ELISA and indirect immunofluorescence methods had identical sensitivity. Moreover, it was shown that identification of IgG antibody was better performed in both diagnostic methods.
Both ELISA and indirect immunofluorescence methods are suitable methods for the detection of antibodies against Listeria.

Brucellosis is an infectious zoonotic disease responsible for reproductive disorders among animals and significant economic losses to the meat and milk supplychain. The purpose of this study was therefore to evaluate and diagnose the species and strains of Brucella isolates among cattles via multiplex polymerase chain reaction.
In this study, blood samples were taken from 22 cows diagnosed as having brucellosis by PCR test. Blood samples were cultured in BACTEC vials and incubated at 37 degrees Celsius for 5 days following which each sample was cultured on Brucella agar and kept for 3 days under Co2 condition.The 16SrRNA gene was used as the target for the detection of Brucella genus and the bcsp31 gene was used for the detection of Brucella biovars. The PCR products were electrophoresed on %1 agarose and compared with standard strains.
The PCR results showed a total of 22 positive samples for Brucella among cattles. Out of the 22 cattle positive samples, 19 were identified as B.abortus (biovars 1, 2, 3, 4, 5) and 3 as B. melitensis (biovars 1, 2, 3).
Brucella abortus biovars 1 and 3 and B .melitensis biovar 1 are the most prevalent biovars among cattles in Lorestan province, Iran. Moreover, multiplex PCR method could be used to improve the qualitative level and the Brucella diagnosis speed in laboratories.

One of the most important factors in food industry is the formation of microbial biofilm which can be the potential source of food products contamination with food spoilage and foodborne pathogenic bacteria. This study was conducted to evaluate the inhibitory effects of zinc oxide nanoparticles on biofilm formation of some foodborne bacterial pathogens.
This research was carried out in 2015. Minimum inhibitory concentration (MIC) of zinc oxide nanoparticles for E. coli (ATCC 35218), Staphylococcus aureus (ATCC 6538), Salmonella typhimurium (ATCC 14028) and Bacillus cereus (ATCC 14579) was determined by using 96-well microplate and resazurin reduction method. Biofilm formation inhibition was assessed with microtiter plate method based on crystal violet staining and measurement of optical density using microplate reader.
MIC of zinc oxide nanoparticles for the above mentioned bacteria was respectively 1, ≤ 0.5, 1 and 2 mg/mL. The inhibition percentages of biofilm formation at the MIC of the nanoparticles were 90.20, 85.69, 83.65 and 61.96, respectively.
In this study, zinc oxide nanoparticle showed the ability to inhibit the formation of biofilm even in sub inhibitory concentrations or Sub-MICs. No significant difference (P>0.05) was observed in the biofilm inhibitory effects of ZnO nanoparticles at MIC and 1/2×MIC between E. coli and S. aureus. Results of this study showed the inhibitory effects of zinc oxide nanoparticles on biofilm formation of the studied foodborne bacterial pathogens. According to the importance of these bacteria in public health, ZnO nanoparticle can be used as a cleaning agent for the surfaces, apparatus and production lines in food plants in order to prevent foodborne bacterial biofilm formation.

Recently inorganic nano materials characterized with high level thermal stability and new physical and chemical properties were considered for antimicrobial therapy. One of the important feature of nanoparticles is their antimicrobial activity against bacteria and food borne pathogens. The aim of this study was to investigate antibacterial activities of copper oxide nanoparticles in combination with nisin and ultrasound against foodborne pathogens.
The antibacterial properties of copper oxide nanoparticles (CuO NP) were investigated alone or in combination with other antimicrobials (nisin and ultrasound stimulation) against Escherichia coli and Staphylococcus aureus in culture media and milk. Also effect of nanoparticle were investigated by scanning electron microscopy individually and combination of CuO and Nisin on morpholohy of S. aureus and E. coli bacteria.
The results show that there was an increasing synergistic effect between CuO NP in combination with nisin. However, the addition of ultrasound stimulation to CuO NP did not enhance the antibacterial activity of CuO. The results show that combined effect of copper oxide nanoparticles and nisin in milk medium were reduced the growth of bacteria. Also the results of the SEM were revealed that CuO nanoparticles and nisin leads to significant change in cell morphology and membrane integrity on bacteria and could be the cause of cell death.
Copper oxide nanoparticles and nisin with regard to the allowed concentration, have a significant effect on the bacteria and perhaps they can be used in food industry, pharmaceutical can be used.

The use of microorganisms in the synthesis of metal nanoparticles is known as an eco-friendly method. Moreover, because of the ability of microorganisms to synthesize nanoparticles of various sizes, shapes and morphologies, this method has gained extreme attentions in recent years. The aim of this study was, therefore, to investigate the antimicrobial effects of silver nanoparticles synthesized by bacteria isolated from agricultural soils of Kerman, Iran.
This study was carried out in 2014. Silver nanoparticles were characterized by SEM, EDS and XRD analyzes. The antimicrobial effects of silver nanoparticles were also assessed against some pathogenic bacteria.
Of the 40 silver nanoparticle producing bacteria, the strains that were able to produce silver nanoparticles with high antimicrobial activity yielded under different environmental conditions, were selected. The results of scanning electron microscopy (SEM) confirmed the presence of silver nanoparticles with a spherical shape. EDS analysis showed that silver content of the particles was about 60 wt %. Sequence alignment and phylogenetic tree results showed that M9 and B7 strains are closely related to Bacillus cereus and Pseudomonas argentinensis, respectively, with 99% homology.
The results showed that the M9 and B7 strains can synthesize silver nanoparticles with high antimicrobial effects under different environmental conditions.

L. monocytogenes is a foodborne pathogen which has a high ability for adapting to unfavorable conditions and is able to growth at refrigerator temperature. An important subject about these bacteria is entering into Viable but non-culturable (VBNC) state under stress. The aim of the present study is considering the culturability of this pathogen under refrigeration (4°C) in rainbow trout fillet matrix. For this purpose bacteria was considered in four treatments: starvation at refrigerator temperature, starvation and high salinity at refrigerator temperature, fish fillet matrix at refrigerator temperature and salted fish fillet matrix at refrigerator temperature during time period by standard cultural methods and 16SrRNA gene expression. The obtained results showed that starvation at refrigerator temperature and high salinity at refrigerator temperature treatments lost their culturability at 13 and 27 days, respectively. The results of gene expression of these bacteria also showed they enter in to viable but non culturable state. The results of fish fillet matrix at refrigerator temperature and fish fillet matrix at refrigerator temperature treatments showed that these bacteria in fish fillet matrix at refrigerator temperature keep their culturability and did not enter in to viable but non-culturable state. Regarded to obtained results in this study could conclude that there is the entering possibility of L. monocytogenes in to VBNC state at refrigerator temperature in view point of bacteria environment and it is necessary to review the microbial quality control methods for refrigeration products.