IRANIAN JOURNAL OF MEDICAL MICROBIOLOGY
Year:2021 | Volume:15 | Issue:3|Papers Count:11

Background and Aim: The endophytes are the fungi or bacteria that live within a plant in a symbiotic relationship. This study aimed to investigate the effect of isolated bacterial endophytes from Allium jesdianum on some bacterial pathogens such as Staphylococcus aureus, Escherichia coli as well as pathogenic fungi, including Trichophyton mentagrophytes and Candida albicans. Materials and Methods: Various parts of A. jesdianum including leaves, stems, onions and flowers were randomly collected, cleaned from any contamination and then cultured in a suitable culture medium. The endophyte colonies were purified using chloroform to analyze the anti-pathogenic properties of the structural agents of the bacterial endophyte. To evaluate the anti-pathogenicity of endophyte metabolites, the broth media of the endophyte bacteria was centrifuged and the supernatants were filtered through sterilization. Antibiogram test was performed by disk diffusion method (Kirby Bauer) and the sensitivity was compared. Data were statistically analyzed by t-test and ANOVA. Results: Eleven bacterial endophytes were obtained from various sections of A. jesdianum. The endophyte bacterium has an improved antimicrobial effect on T. mentagrophytes. Unlike E. coli, secretory metabolites of endophytic bacteria had an antimicrobial effect on S. aureus and C. albicans. Conclusion: It can be concluded that the bacterial endophytes of A. jesdianum can be considered to be potential and beneficial agents against human pathogens. A. jesdianum with anti-pathogenic activity could be a source to produce important anti-pathogenic compounds from an agricultural and pharmaceutical point of view.

Background and Aim: The pyocyanine pigment in Pseudomonas aeruginosa stimulates blood cells to secrete IL-2. IL-2 cytokine is an activator of cytotoxic T cells and natural killer cells. These cells destroy the target cells of patients with cancer. This study aimed to evaluate the effects of pyocyanine on the IL-2 secretion from peripheral blood mononuclear cells (PBMCs) in patients with breast, prostate, and bladder cancers. Materials and Methods: : . In this cross-sectional descriptive study, a total of 30 P. aeruginosa isolates were collected from different clinical specimens (urine, blood, burns, etc. ) of patients admitted to Namazi Hospital in Shiraz, Iran, from October to December 2019. The pyocyanine was extracted from the isolates by chloroform. Also, twenty-eight peripheral blood samples were selected from 21 patients with breast, prostate, and bladder cancers and 7 healthy controls. Following the isolation of PBMCs from patients and the control group using Ficoll density gradient, samples were prepared for cell culture. Half of the PBMCs were treated with pyocyanine (0. 5 μ g/mL), and the rest of them remained without treatment. Then, the IL-2 secretion from the treated and untreated cells with pyocyanine was investigated by ELISA method. Statistical analysis was done using SPSS 22. Results: Significant increases were seen in the IL-2 secretion from PBMCs in the patients with breast (P=0. 032), prostate (P=0. 002), bladder (P=0. 009) cancers, and healthy controls (P=0. 004) after treatment with pyocyanine in comparing with before treatment with this pigment in vitro. Conclusion: Low concentrations of pyocyanine can stimulate the PBMC of cancer patients to secrete IL-2 cytokines. Further studies should be performed on the immunostimulatory effects of pyocyanine in laboratory animals.

Background and Aim: Acinetobacter baumannii is considered to be a re-emerging causative agent of nosocomial infections. There is a significant relation between pathogenicity of this bacterium and the numerous virulence factors. The purpose of this study was to investigate nine virulence factor genes in A. baumannii isolates derived from hospitalized patients. Materials and Methods: A total of 50 A. baumannii isolates were recovered from patients with pneumonia in Imam Khomeini Hospital, Tehran, Iran. Following biochemical and microbiological identification of the bacteria, Multiplex PCR was performed for basD, plD, csuA genes, surA, pbpG, bfmR genes, and bap, ompA genes using specific sets of primers which were specifically designed for this study. The espA was identified separately by a Uniplex PCR assay. All amplified DNA fragments were sequenced for the products’ confirmation. Results: Among the 50 clinical isolates of A. baumannii studied, bfmR and pbpG genes were reported in all samples (100%), bap, plD, surA, and csuA genes were collected from 49 samples (98%), 48 (96%) of these isolates had ompA and basD genes, and espA gene was observed in only five isolates (10%). Conclusion: According to this study results, virulence factors genes in clinical A. baumannii have a prevalence rate more than 90%. Additionally, the high incidence rate of those genes related to biofilm formation indicates that most clinical strains have the ability to form biofilm structures.

Background and Aim: Antimicrobial peptides have attracted significant attention in recent decades because of their properties, such as rapid bactericidal effects, having a wide spectrum of activity, and a rare development of drug resistance. The purpose of this study was to examine the antibacterial activity of a peptide derived from the lactoferrin isolated from camel milk against Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii. Materials and Methods: In the present study, by means of bioinformatics, an antibacterial peptide was potentially identified as candidates in lactoferrin of camel milk, and an appropriate peptide was selected based on defined criteria. The Pepsin-Camel-Lac1 peptide was synthesized. The methyl thiazolyl diphenyl-tetrazolium bromide assay was conducted to examine the toxicity of Pepsin-Camel-Lac1 against a cell line. Three pathogenic bacteria, namely S. aureus, P. aeruginosa, and A. baumannii were analyzed to assess the antibacterial activity of Pepsin-Camel-Lac1 peptide. Results: The results showed that the newly-identified peptide had no toxicity against the cell line. The minimum inhibitory concentration values of Pepsin-Camel-Lac1 against S. aureus, P. aeruginosa, and A. baumannii were 31. 25 μ g/mL, 31. 25 μ g/mL, and 62. 5 μ g/mL, respectively. Conclusion: It seems that the growth of S. aureus, P. aeruginosa, and A. baumannii was not affected by Pepsin-Camel-Lac1 treatment in the bacterial culture medium.

Background and Aim: Milk is a completely rich and complex environment suitable for different microorganisms including bacteria and Fungi. The majority of studies were conducted on milk-bacterial flora and aflatoxin-contaminations in dairy products; however, despite the importance of yeasts in usage as starter in the dairy industries and their effect on the taste of dairy products as well as in dairy probiotic characteristics, almost no information exist concerning fungal-flora in milk. So, the aim of this study was investigation on the raw milk yeast-microflora and it’ s relation to the hygienic level and other characteristics of dairy farms. Existence of fungus were studied in defined raw milk samples and the diversity of isolated yeasts were examined. Materials and Methods: Samples were collected within a period of one year (March 2016-March 2017) and evaluated based on Internal Transcribed Spacer (ITS-1-ITS-2) parts of rDNA. Isolated yeasts were identified using PCR-RFLP and Sequencing tests. Results: Total of 262 raw milk samples were collected from 14 farms in Tehran and Alborz provinces in Iran. About 66% of milk samples contained yeast microflora. The dominant isolated yeasts were characterized as: Candida globose, Geotrichum candidum, Pichia kudriavzevii, Tricosporon asahii, Pichia jadinii, Kluyveromyces marxianus, Magnusiomyces capitatus, Wickeihameilla pararugosa, and Candida inconspicua. Other candida species such as Candida parapsilosis, Candida tropicalis, and Candida glabrata were also isolated in a limited level. Conclusion: Dominant yeast flora was identified in raw cow’ s milk samples. The obtained results also indicated that fungal diversity varies from field to field. However, similarities in some isolated species have been revealed.

a predisposing factor of gastric adenocarcinoma. Cytotoxin A encoded by the cagA gene is one of the major virulence factors in bacterial pathogenicity, which is of special importance due to genetic diversity in different geographical areas. The purpose of this study was to evaluate the prevalence of the cagA gene in the patients suffering from gastric ulcers. Materials and Methods: Seventy-five paraffin blocks of stomach biopsy samples from patients infected with H. pylori and suffering from gastric ulcers were randomly evaluated in the province of Kermanshah in the spring of 2016, Iran. DNA samples extracted by the boiling method were investigated using PCR by the use of particular primer pairs for a protected area in the glmM gene, and the existence of the cagA gene. Results: From the 75 samples, 56 cases (%74. 66) were glmM-positive and among them, 39 cases (%69. 64) tested positive for cagA gene. Comparing patients in terms of gender, the frequency of the cagA gene was 22 (%39. 28) and 17 (%30. 35) in males and females, respectively. Finally, comparing patients in terms of age, 16 cases (%21. 33) were younger than 40 years old and 23 cases (%41. 07) were older than 40 years old. Conclusion: The results of this study showed significant association between the frequency of the cagA gene and peptic ulcer in the studied patients.

Background and Aim: Dairy fermented foods such as yogurt, cheese, fermented milk, butter milk, curd, butter and ghee are used as major diet ingredients in west of IRAN, such as Kermanshah province. Ghee (Kermanshahi traditional oil or roghan-e heiwâ ni) is traditionally produced from butter milk of yoghurt after fermentation. Review of the literature yielded no study on isolating probiotics from Kermanshahi traditional oil preparation stages. Therefore, purpose of this study was just to focus on isolating and identifying lactic acid bacteria in these products using culture and PCR-sequencing methods. Materials and Methods: Fifteen samples from each dairy products including yogurt, butter and Kermanshahi traditional oil were collected in Kermanshah province, Iran. Each sample was diluted, homogenized, and cultured on selective medium for growing of lactic acid bacteria. 16SrRNA gene sequences analysis was carried out for final confirmation of these isolates. Results: After culturing of samples on MRS and M17 under aerobic and anaerobic condition, a total of 78 strains of bacteria were isolated and identified by conventional biochemical tests. The frequency of bacteria in all isolates (78) were 48. 71% for Lactobacillus, 33. 33% for Streptococcus, 6. 41% for Enterococcus and 6. 41% for Bacillus. Lactobacillus, Streptococcus, Enterococcus, and Bacillus genus, were isolated from 84. 44%, 57. 78%, 11. 11% and 15. 56% of all three kind of samples, respectively. Conclusion: Based on our findings, Lactic acid bacteria and other potentially probiotic microorganisms are present in Kermanshahi traditional oil. Of course, the potential probiotic properties of these isolates and impact of consumption of Kermanshahi traditional oil containing those on human health need to be analyzed more. By proving the presence of probiotic bacteria in Kermanshahi oil, it may be falls in the category of functional foods.

Background and Aim: Coronavirus disease known as COVID-19 pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is affecting over 200 countries all over the world. This study was aimed to identify simple and swiftly available laboratory biomarkers to help facilitate effectual triage to categorize suspected COVID-19 patients. Materials and Methods: According to a standard protocol, we collected clinical, etiological, and laboratory data of 140 patients who underwent diagnostic tests at Medical Laboratory Group, Tehran, Iran, from October 1 to November 28, 2020, based on PCR testing for SARS-CoV-2 infection. Leukocyte parameters, C-reactive protein (CRP) and, ferritin levels were measured in patients with positive PCR COVID-19 test. Results: 140 patients with COVID-19 infection were included in the study. The median age in women was 41. 5 (23-60) years and 45. 3 (22-68) years in men. Based on RT-PCR result, there were significant differences for neutrophil, lymphocyte, and monocyte counts. Overall, 72. 8% of patients had monocyte count more than 11 ×109 /L. The mean neutrophil lymphocyte ratio (NLR) for women was 2. 8 (SD: 1. 8) and 2. 6 (SD: 1. 7) for men. Only in 15 patients (10. 7%) with respiratory symptoms, CRP level was more than 5 mg/L. Conclusion: We found a significant increase in monocyte count. Lymphopenia was also observed. In patients with respiratory symptoms, CRP was significantly higher than the normal reference range.