Jundishapur Journal of Microbiology
Year:2018 | Volume:11 | Issue:6|Papers Count:8

To the editor, In developing countries, inadequate meat processing facilities, and unhygienic environments at slaughterhouses cause occupational hazards to workers, meatconsumers, or anyone exposed to that environment. Multiple flaws e. g. inadequate training, inadequate infrastructure, poor hygiene etc. contaminate the meat and transmit pathogens. The transmission of viral infections through meat-sellers is one of the most neglected public-health risks. This mode of transmission is least focused in the literature, while occupational transmission of viruses is always discussed in context of trading of diseased animal meat. However, there is not a single study that highlights the role played by butchers (who themselves are positive for multiple viral infections) in transmission of viruses.

Background: Pharyngeal carriers are the source and transitional vectors of invasive diseases. Attachment is the first step in pathogenicity. Strains of Streptococcus as normal flora can cause diseases in certain circumstances. Adhesion proteins of these bacteria play a fundamental role in the attachment and colonization. Objectives: In the present study, 5 genes encoding surface proteins namely phtD, pspC, phtE, lytA, and rrgA were evaluated in Streptococcus pneumoniae isolates collected from 4 main care centers and the children’ s Medical center in Tehran. Methods: Three hundred and eight nasopharyngeal swab specimens were collected from children under 6 years. The identification of S. pneumoniae isolates was performed using biochemical tests confirmed by PCR for the presence of cpsA gene. The existence of phtD, phtE, pspC, lytA, and rrgA genes was studied by PCR amplification assays. Results: From308 nasopharyngeal swabs, 102 isolates of S. pneumoniae wereconfirmedby identification tests. Amongthese isolates, 87 (85. 2%), 54 (52. 9%), 51 (50%), 43 (42. 1%), and 31 (30. 3%) were positive for lytA, rrgA, phtE, pspC, and phtD genes, respectively. Conclusions: Our study showed that cpsA of S. pneumoniae is one of the major characteristic genetic markers for diagnostic purposes. Among five adhesion genes, lytA was the most frequent one and the strains with a combination of rrgA and lytA genes were predominant. These findings could be very useful in designing further studies on vaccines against S. pneumoniae in our country.

Background: The spread of Staphylococcus aureus and the types of infection caused by S. aureus are closely related to the secretion of a variety of adhesion proteins, which could be controlled by a variety of regulatory systems. However, for the newly discovered adhesion protein SasX, the regulatory mechanism is not completely clear. Objectives: The current study aimed at investigating the regulation of Staphylococcal accessory gene regulator A (agrA), Staphylococcal accessory regulator A (sarA), and two-component signal transduction system (saeRS) on the adhesion protein SasX. Methods: In this research, a saeRS mutant strain, a sarA mutant strain, and a agrA mutant strain were constructed by allelic replacement. In this study mRNA and protein expression levels of sasX in wild-type HS770 and knockout strains were studied to investigate the effects of regulatory factor saeRS, agrA, and sarA on adhesion protein SasX. Results: In contrast with the wild strain HS770, the transcriptional expression of sasX was highest at on the sixth hour time point in HS770
agrA and at nine and twelve hours in HS770
sarA. However, the sasX transcription level in HS770
saeRS mutant strains had little change at different time points. Western-blot results suggested that the sasX expression level of wild strains was the highest at 6 hours; HS770
saeRS mutation strains had no expression peak at 6 hours. The expression level of HS770
agrA mutant strains decreased at 6 hours of expression, however, increased at 9 hours and 12 hours; the expression level of HS770
sarA mutation knockout increased at three, six, nine, and twelve hours. Conclusions: All the results showed that agrA and sarA have negative regulation on sasX, but saeRS may not regulate sasX.

Background: The semi-synthesis of drugs from natural products is still limited and complicated. Recently, there has been compelling global need to develop novel and potential antibacterial and antioxidant agents. Objectives: The current study aimed at semi-synthesizing new derivatives from naringin, to verify their chemical structures and assess their antibacterial and antioxidant potentials. Methods: The semi-synthesis of naringin was conducted in the presence of hydrazone and oxime derivatives in acidic solution, while elemental and spectral analytical methods were used to verify the chemical structures of the semi-synthesized molecules. Also, to assess their antibacterial activity, the micro-broth dilution method with different American type culture collection (ATCC) strains as Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and clinical isolate methicillin-resistant Staphylococcus aureus (MRSA) were utilized. Moreover, 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) was used to assess the antioxidant activity of the derived compounds. Results: Three new hydrazone and oxime compounds were semi-synthesized from naringin and their chemical structures were identified by 13CNMR, IR, MS, and 1HNMR. Amongthe semi-synthesized compounds, the (2a) molecule showed the best antibacterial activity with a minimum inhibitory concentration (MIC) value of 62. 5  g/mL. Also, this compound exhibited the best antioxidant activity with IC50 3. 7  g/mL, in comparison with the other studied samples. Conclusions: Hydrazone (2a) compound could be used as a potent antioxidant and bacterial agent. Further studies are required to investigate other therapeutic effects of the (2a) molecule.

Background: Identification of antibiotic resistance Acinetobacter baumannii can help us control and prevent the infections and reduce the mortality rates caused by this microorganism. Objectives: This study aimes to identify the insertion elements that can playimportant roles in antibiotic resistance in A. baumannii. Methods: A total of 105 A. baumannii isolates from clinical samples were tested for their susceptibility to different antibiotics using disc diffusion test (DDT). Then, the isolates were evaluated for the presence of blaOXA genes along with IS elements by polymerase chain reaction (PCR). Results: PCR analysis showed that ISAba1 was present in all the isolates while 92. 36% of the isolates were positive for ISAba2. All the strains of A. baumannii possessed a blaOXA-51-like gene but blaOXA-58-like gene was absent in all of them. About 64. 76% of the isolates were positive for blaOXA-24-like gene and 98. 09% were positive for blaOXA-23-like gene. All of the isolates were pandrug resistant A. baumannii and the lowest resistance rates were observed toward minocycline and amikacin (93. 33% in both) and trimethoprim/ sulfamethoxazole (92. 38%). Conclusions: The high prevalence rates of ISAba1 and ISAba2 among A. baumannii isolates can explain the rapid dissemination of resistance genes. Thus, finding the accessory genes such as IS elements, which can affect antibiotic resistance, should be more considered.

Background: There are clear variations between and within countries regarding the prevalence of Helicobacter pylori. In addition, there are no estimations of its prevalence in the general population in the south of Iran. Objectives: We aimed to evaluate the prevalence of H. pylori in the rural population of Kavar, a southern city of Iran. Methods: A random sample of 500 individuals were selected from the Kavar cohort study. Serum total IgG against H. pylori was checked. The serum positive patients recalled for stool sampling and the H. pylori stool antigen was checked using sandwich ELISA. Moreover, age and gender were recorded for all patients. Results: Among the remained 441 who participated, 254 patients (57. 6%) were positive for serum IgG. A total of 14 patients (5. 5%) gave up due to stool sampling unsatisfaction. Overall, the rate of H. pylori infection based on both serum IgG and stool Ag of H. pylori was 41. 5%. There were no significant association between gender and H. pylori stool antigen positivity (P = 0. 776). Furthermore, no differences were detected between different ages categorized in positivity for stool antigen of H. pylori (P = 0. 327). The mean and SD of age for negative and positive groups were 40. 98 15. 42 and 43. 65 15. 65 years, respectively (P = 0. 267). Conclusions: The prevalence of the H. pylori infection in our study based on serum IgG and stool Ag positivity was 41. 5%, which are lower than many previous reported rates. Further studies in larger sample size and in different rural populations are needed.

Background: Increasing azole resistance among Aspergillus strains was observed over the last decade. For this reason, viable alternatives for the current medicines are required. Objectives: The current study aimed at producing fluconazole-loaded liposomal nanoparticles and comparing in vitro antifungal activity of fluconazole and nano-fluconazole on Aspergillus flavus and A. fumigatus species isolated from patients and poultry. Methods: Fifty isolates of A. flavus and A. fumigatus were collected from visceral and superficial fungal lesions of humans as well as pulmonary fungal infection of poultry. Liposomal nanoparticles were prepared by thin-film hydration method, using soybean lecithin, cholesterol, and fluconazole in a ratio of 10: 1: 1. The nanoparticles were analyzed in terms of size, zeta potential, and morphology. Antifungal susceptibility testing was carried out to examine and evaluate the minimum inhibitory concentration (MIC) of fluconazole and nano-fluconazole against Aspergillus species by the standard method of broth microdilution as described in CLSI (the clinical and laboratory standards institute)-M38A2. Results: The particle size of liposomes containing fluconazole was 88. 9 12. 1 nm and its zeta potential was-20. 12 1. 88mv. Nanoliposomes containing fluconazole significantly reduced the MIC against A. flavus (P = 0. 0005) and A. fumigatus (P < 0. 0001). Conclusions: The results of the current in vitro study showed that nano-fluconazole has better antifungal effects than the common form of drug on A. flavus and A. fumigatus species. The current study showed the antifungal activity of nano-drugs.

Background: Prophylactic and therapeutic uses of antifungal agents have given rise to a significant shift to more resistant nonalbicans Candida species associated with fungal infections. Objectives: This study aimed at identifying the distribution and antifungal susceptibility patterns of non-albicans Candida spp. isolated from clinical specimens in Tokat, Turkey. Methods: The authors determined the susceptibility of 103 non-albicans Candida isolates to the following antifungal agents: amphotericin B, anidulafungin, caspofungin, fluconazole, ketoconazole, itraconazole, voriconazole, and posaconazole, using the Etest method. Interpretation of susceptibility was carried out using species specific breakpoints suggested by the Clinical and Laboratory Standards Institute (CLSI) M27-S4 document. Results: The most frequently isolated non-albicans Candida species were Candida kefyr (44 isolates, 42. 8%) followed by C. tropicalis (36 isolates, 35%), C. parapsilosis (17 isolates, 16. 5%), C. glabrata (four isolates, 3. 8%) and C. famata (two isolates, 1. 9%). None of the strains had MIC values of > 2 g/mL for amphotericin B except three of the 44 C. kefyr isolates. Resistance to caspofungin and anidulafungin were not detected in C. tropicalis, C. parapsilosis, and C. glabrata isolates. Only two of the 36 C. tropicalis isolates were categorized as intermediate resistant to anidulafungin, according to the new CLSI criteria. None of the C. parapsilosis isolates were found to be resistant to azole drugs. Conclusions: Most of the non-albicans Candida species were found to be susceptible to tested antifungal drugs. Therefore, use of routine antifungal agents like amphotericin B and fluconazole, which are available in this region, are suggested.