Jundishapur Journal of Microbiology
Year:2017 | Volume:10 | Issue:10|Papers Count:7

Background: Carbapenem-resistant Klebsiella pneumoniae isolates can spread among the hospitalized patients and result in serious infections and increase mortality. Molecular studies provide useful information about resistance mechanisms and crosstransmission among the resistant isolates. Objectives: The current study aimed at investigating phenotypic and molecular characteristics of the carbapenem resistance and clonal relationship among the K. pneumoniae isolates recovered from infection sites and rectal swabs of the patients hospitalized in a tertiary hospital. Methods: Resistance to carbapenems was investigated by disc-diffusion and E-test methods. Modified Hodge test (MHT) and ethylenediaminetetraacetic acid (EDTA)-combine disc (ECD) methods were performed to determine carbapenemases. Carbapenemase-encoding genes including blaOXA-48, blaNDM-1, blaKPC, blaIMP, and blaVIM were investigated by multiplex polymerase chain reaction (PCR). Clonal relationship among the isolates was determined by the pulsed-field gel electrophoresis (PFGE). Results: Carbapenem resistance was observed in 93 (5. 8%) of the 1605 K. pneumoniae isolates. Majority (n = 66, 71%) of the resistant isolates were recovered from the patients in intensive care units (ICUs). Almost all carbapenem-resistant K. pneumoniae isolates (n = 91, 97. 8%) were positive with MHT. Only 6 (6. 5%) of the resistant isolates were positive with ECD method. The blaOXA-48 and blaNDM-1 were found in 90. 3% (n = 84) and 6. 5% (n = 6) of the resistant isolates, respectively. The pulsed-field gel electrophoresis yielded 55 different pulsotypes. Fifteen pulsotypes were identified as clusters with  2 isolates and a clustering rate of 57%. Based on the similarity coefficient higher than 85%, a total of 75 (80. 6%) isolates were clonally related to each other. Conclusions: The high rate of carbapenem resistance and 80. 6% clonal relationship between the isolates collected in a 3-year period indicated a serious potential threat for the hospital-acquired infections and pointed longtime cross-contamination.

Background: A viral etiology for several malignancies has been suggested. One of the risk factors for development of breast carcinoma, which is the leading malignancy in women all over the world, is proposed to be a viral infection; hence recognition of the causative issues is essential for proper management. Objectives: Epstein-Barr virus (EBV) infection is reported to be associated with breast carcinoma. This study was conducted to detect the presence of EBV-DNA in breast cancer in Iranian patients. Methods: In this case-control study, the prevalence of EBV-DNA detection was investigated by qualitative real-time polymerase chain reaction (RT-PCR) using paraffin-embedded tissue samples of 75 women with breast cancer and 75 cases with benign breast lesions or normal breast tissue, which were examined between 2005 and 2014 at the pathobiology laboratory center, Tehran, Iran. The pathology reports of the patients were reviewed, retrospectively. Results: In 7 cases (9. 3%) of malignant lesions and 0% of benign lesions, the EBV-DNA was found, showing a statistically significant difference according to the Fisher test (P = 0. 014, Odds Ratio: 0. 907; 95% CI of OR: 0. 843-0. 975). Conclusions: According to our results, it can be suggested that EBV may have an etiologic role in breast cancer in Iran. The confirmation of the etiologic role of EBV in the induction of breast carcinoma needs more studies using more specific and sensitive techniques.

Background: Invasive fungal infections acquired in the hospital have progressively emerged as an important cause of lifethreatening infection. In particular, airborne fungi in hospitals are considered critical pathogens of hospital-associated infections. Objectives: This study aimed to investigate the airborne fungi of indoor environments of educational hospitals in the city of Ahvaz, Iran. Methods: The air samples were taken from seven wards in five hospitals using Quick Take 30 samplepump. A total of 175 air samples were cultured into Sabouraud dextrose agar and incubated at 25° C for 7 to 10 days. Fungal species were identified by macroscopic and microscopic features. The number of airborne fungi was presented in colony-forming unit per cubic meter (CFU/m3). Results: A total of 2906 fungal colonies were isolated. The highest and least numbers of fungi were related to surgical (446 CFU/m3) and neonatal intensive care unit wards (103 CFU/m3), respectively. The most frequent fungal species was Cladosporium spp. (35. 3%), followed by yeasts (27. 3%), Aspergillus spp. (15. 1%), Penicillium spp. (12. 1%), and other fungal species (10. 2%) Conclusions: All wards under study were heavily contaminated with different types of fungi. Thus, it is suggested to monitor the indoor air to prevent possible hospital infections.

Background: Pseudomonas aeruginosa is a Gram-negative and rod-shaped opportunistic pathogen highly involved in biofilm production in chronic wounds. Biofilms in wounds are the main cause of resistance tomultiple antimicrobial agents. This study aimed to identify biofilm-producing bacteria most frequently found in chronic wounds and to examine the association of antibiotic resistance among the isolates. Objectives: This study was to evaluate the isolation of P. aeruginosa from different types of chronic wounds, as one of the causes of delay in wound healing and biofilm formation, as well as to determine the association of antibiotic resistance among the isolates. Methods: Ninety-one isolates of chronic wounds were obtained fromDHQHospital KDA District Kohat (Khyber Pakhtunkhwa), Pakistan, from September 2014 to June 2015. Isolates of P. aeruginosa from different types of chronic wounds were biochemically identified and confirmed by molecular identification of one of the conserved genes, algD GDP-mannose dehydrogenase, in P. aeruginosa. Biofilm-forming ability and effects of antibacterial agents were also determined. Results: The prevalence of diabetic ulcer was found to be more (62. 5%) compared to other types of chronic wounds in patients, and 48. 3% of the isolates were identified as P. aeruginosa. The prevalence of P. aeruginosa in males was found to be higher (56. 8%) than in females, with a statistically non-significant association. Furthermore, biofilm formation was observed in the isolates, so that 79. 5% of P. aeruginosa isolates were found to be biofilm producers. Antibacterial drugs were applied to the culture of isolates, showing that P. aeruginosa was more resistant to ceftriaxone while amikacin acted as a bactericidal. Conclusions: From our research, we conclude that delay of wound healing was because of biofilm-producing bacteria found in chronic wounds, which were more resistant to antibiotics because of the ability of biofilm forming. Further, amikacin showed a good activity against P. aeruginosa.

Background: Malaria, as a parasitic disease, is one of the most important public health problems in Iran. Malaria is mainly diagnosed by peripheral blood smear, stained by Giemsa; in Iran it is also diagnosed by blood smear that is highly depends on technician’ s skills and laboratory properties. Objectives: Correct diagnosis of malaria and identification of human malaria species in spite of the measures taken to eliminate the disease in Iran, have made the complete understanding of malaria epidemiology critical. Therefore, the current study aimed at investigating the epidemiology of 2 species of human Plasmodium in Sistan and Baluchistan province using polymerase chain reaction (PCR) method. Methods: The present descriptive study was conducted on 100 patients suspected to malaria infection who referred to health centers of Chabahar, Iranshahr, Nikshahr, and Sarbaz districts. DNAs were extracted from blood samples using the specific kit, and nested-PCR reaction was performed to identify the Plasmodium species according to NP-2013 protocol. Results: Molecular analysis was performed on 100 samples suspected of malaria; 84 negative and 16 positive samples were detected including 8 Plasmodium vivax, 2 P. falciparum, and 6 mixed infections (P. vivax and P. falciparum). No P. ovale or P. malariae was observed. Conclusions: The results showed that malaria had a decreasing trend in Sistan and Baluchistan province. Therefore, the malaria elimination program is applicable and attainable in this region as a goal.

Background: Nanoparticles are made by different methodologies, which can affect the particle’ s features. Recently, imidazoliumcoated silver nanoparticles with a positive surface charge (PC Im-based AgNPs) have revealed favorable results as a root canal disinfectant. However, the antibacterial potency of these particles against biofilm form of Enterococcus faecalis, as the most resistant organism to eliminate in endodontic treatment, has not been investigated. It can be noted that removing this microorganism is associated with extremely effective disinfection. Objectives: This study investigated the antibacterial efficacy of PC Im-based AgNPs at 5. 7  10-8 mol L-1 in comparison with 2. 5% sodium hypochlorite (NaOCl) and 2% chlorhexidine as the two broadly used endodontic irrigation solutions against biofilm E. faecalis using quantitative real-time polymerase chain reaction. Methods: In total, 48 premolar teeth with a single root were infected with E. faecalis and then prepared with ProTaper rotary instruments. The samples were randomly allocated into 4 groups of 12 samples. Sterile saline, PC Im-based AgNPs, NaOCl, and chlorhexidine were used as irrigants. Sampling the root canals was implemented with paper points and Gates-Glidden drills. The reduction in E. faecalis counts was calculated and statistically analyzed by means of the Kruskal-Wallis and Mann-Whitney U tests. Results: Irrigation with PC Im-based AgNPs or NaOCl was significantly more effective in bacterial count reduction compared to irrigation with chlorhexidine or sterile saline (P < 0. 05). There was no significant difference between PC Im-based AgNPs and NaOCl irrigants when either Gates-Glidden drills (P = 0. 751) or paper points (P = 0. 488) were employed. Chlorhexidine was significantly lessefficient than PC Im-based AgNPs and NaOCl solutions (P < 0. 001); however, it was significantly better than sterile saline in both sampling approaches (P > 0. 001). Conclusions: The PC Im-based AgNP solution revealed promising results as a root canal irrigant. This solution at 5. 7 10-8 mol L-1 was effectively able to eliminate biofilm E. faecalis and this was not significantly different from that of 2. 5% NaOCl.

Background: Brucella spp. are Gram-negative bacteria that cause a zoonotic disease called brucellosis in humans as well as many animals. Brucella suis (B. suis) is one of the greatest threats to the human health and food safety. Studying macrophage and B. suis interaction is critical for understanding the chronic infection mechanism. However, the interaction mechanisms, especially for molecular events triggered by B. suis infected macrophage, such as biological pathways, are still obscure. Objectives: We will use gene set enrichment analysis (GSEA) to microarray in an attempt to find critical pathways in the interaction of macrophage and B. suis. Methods: We applied a standardized microarray preprocessing and GSEA to 2 independent macrophage and B. suis interaction studies including smooth virulent B. suis strain 1330 (S1330) data sets and rough attenuated B. suis strain VTRS1 (VTRS1) data sets. Integrative analysis was used to find critical pathways for 2 independent macrophage and B. suis interaction data sets. Results: The results demonstrated that for S1330 data sets, 8 and 13 common up-and down-regulated pathways were found in 4 interaction stages including 4h, 8h, 24h, and 48h post macrophage infected S1330 B. suis, and for VTRS1 data sets, we found 30 and 19 common up-and down-regulated pathways. Comparing the results of S1330 and VTRS1 data sets, 6 and 8 common up-and downregulated pathways were identified. Conclusions: The study ofmacrophage and B. suis interaction through pathway analysis highlighted genes weakly connected to the phenotype, and discoveredcommoncritical pathways in the process of macrophages and different phenotypes of B. suis interaction. The identified pathways will shed light on the understanding of the functional events within macrophage post infected B. suis.