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1.
Iran J Microbiol ; 15(4): 574-584, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38045709

RESUMO

Background and Objectives: The present study was to evaluate the microbial diversity inhabiting biodeteriorated precious manuscripts of the Holy Quran placed in one of the repositories of the Library of Astan Quds Razavi (AQR), and its relation to the air microbial diversity. Materials and Methods: Three non-invasive sampling methods, culture-based techniques, and molecular identification were used to investigate the microorganisms involved in deterioration. To investigate the air microbial quality and its role in the destruction of the repository objects, air samples were taken from six different points inside the repository. Biomodeling studies were designed to verify the impact of microbial isolates. Results: 14 fungal isolates were obtained from three deteriorated ancient Quran manuscripts. The most frequently isolated fungi from the different substrates were Aspergillus spp. and Penicillium spp. In the air, the prevalence across fungal genera was rather uniform. 30 species of the identified bacteria were collected from three manuscripts. The results obtained in the present study showed that the bacterial species from different genera belonged to three phyla: Proteobacteria (n = 2), Actinobacteria (n = 4), and Firmicutes (n = 24). The paper strips were artificially colonized by Aspergillus sp., Penicillium chrysogenum, and Talaromyces diversus producing spots which were visible to the naked eye. In the scanning electron microscopy images, the colonization of the selected organism was observed. Conclusion: The characteristics of paper inoculated artificially with these microbial isolates confirmed their deteriorating effects. Based on molecular identification, the similarity of fungal and bacterial species isolated from both substrates and air samples suggest the direct relationship between microorganisms from the air and those isolated from the manuscripts.

2.
Microb Pathog ; 181: 106170, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37257667

RESUMO

The hepatitis B virus (HBV) infection has a wide range, from fulminant hepatitis to inactive chronic hepatitis B (ICB) infection. The present study evaluated critical factors in the outcomes of HBV infection in a highly endemic region of Iran (approximately 12% HBV positive). The expression of seven genes involved in host immunity (Foxp3, T-bet, ROR-γt, AKT, CREB, IL-28/or IFN-λ2, and IL-28R) and HBx for viral activities were evaluated using real-time PCR, TaqMan method. A total of 58 subjects were randomly chosen, including 28 ICB and 30 healthy controls (HCs) from the Esfandiar district, South Khorasan province, Iran. The expression index of Foxp3 and ROR-γt was moderately up-regulated in ICBs but did not statistically significant. T-bet expression in ICB patients was significantly higher than in HCs (p = 0.004). Furthermore, evaluating two signalling pathways in Th activation and cell survival showed that the CREB pathway was significantly up-regulated in ICB patients compared to HCs (p = 0.006), but the AKT did not differ. In innate immune responses, the IL-28/or IFN-λ2 expression in ICB patients was significantly higher than in the HCs (p = 0.02). Surprisingly, only one ICB patient disclosed HBx expression, which shows deficient virus activity in these patients. The ICB condition seems to result from host immune pressure on HBV activities, up-regulation of T-bet and IFN-λ. The high expression of CREB may prevent Kupffer's pro-inflammatory reactions in the liver. Whereas the absence of HBx expression in ICB patients and, consequently, the inactivity of HBV may also confirm such immune pressure.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Transativadores/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Proteínas Virais Reguladoras e Acessórias , Proteínas Proto-Oncogênicas c-akt/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Fatores de Transcrição Forkhead
3.
J Appl Genet ; 63(2): 401-412, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35143031

RESUMO

Of the most common infectious diseases that occur mainly by uropathogenic Escherichia coli (UPEC) is urinary tract infections (UTIs). The purpose of this study was to investigate virulence factors, antibiotic resistance, and phylogenetic groups among UPEC strains isolated from patients with UTI in southern Iraq. A total of 100 UPEC isolates were collected from urine samples of UTI patients from various hospitals in southern Iraq, and confirmed by morphological and biochemical tests. Antimicrobial susceptibility testing on isolates was performed by disk diffusion method. Multiplex PCR techniques were used to evaluate the phylogenetic groups based on Clermont method and to detect the presence of six virulence factor genes. The majority of isolates belonged to the phylogenetic groups B2 (46%) and C (13%). The most prevalent virulence factors were fimH (96%), followed by aer (47%), papC (36%), cnf1 (17%), hly (15%), and afa (8%). Phenotypic testing showed that the isolates were most resistant to piperacillin, ticarcillin, amoxicillin/clavulanic acid (92%, 91%, and 88%, respectively) and most sensitive to amikacin and imipenem, respectively. The maximum antibiotic resistance and virulence factors were observed in the phylogenetic group B2. The results showed that the UPEC isolates had all six virulence factors with high frequency and the highest drug resistance. Besides, the results showed a direct relationship between virulence factors, gene diversity, phylogenetic background, and antimicrobial resistance in the UPEC isolates.


Assuntos
Infecções por Escherichia coli , Escherichia coli Uropatogênica , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Iraque , Filogenia , Escherichia coli Uropatogênica/genética , Virulência/genética , Fatores de Virulência/genética
4.
Curr Microbiol ; 77(9): 1959-1967, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32623484

RESUMO

Acinetobacter species are defined as multidrug-resistant pathogens and the development of resistance against antimicrobials is a major problem in the treatment of infections caused by them. This study aimed to evaluate the antibacterial activity of aqueous and methanol extracts of Salvia chorassanica and Artemisia khorassanica on multidrug-resistant Acinetobacter isolates and also examining the interaction of the methanol extract of the plants with the combination of amikacin and imipenem. First, the presence of adeI and adeB genes in bacterial isolates was investigated. The aqueous and methanol extracts of the leaves of the plants were prepared by Maceration method. Minimum Inhibition Concentration (MIC) values were determined to evaluate the antibacterial activities of plant extracts and antibiotics. Combined effects of the antibiotics with plant extracts were performed using the checkerboard method. The accumulation assay was used to examine the inhibitory effects of plant extracts on the bacterial efflux pump. MIC results indicated that the methanol extracts were effective against Acinetobacter species. FICI values indicated that the combination of antibiotics with methanol plant extracts improves bacterial sensitivity to antibiotics. The extracts also exhibited efflux pump inhibitory activities. Consequently, combination of the plant extracts with antibiotics could enhance the antibiotic susceptibility of resistant pathogens.


Assuntos
Acinetobacter baumannii , Imipenem , Amicacina , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
5.
Extremophiles ; 24(5): 693-704, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32617734

RESUMO

A new keratinase producer, Bacillus sp. BK111, isolated from a poultry feather was identified as Bacillus zhangzhouensis, which is the first report for its keratinolytic activity. The keratinase production was optimized, followed by the enzyme purification and characterization using biochemical assays. A 2.34-fold increase was observed in the enzyme production under optimized conditions. The enzyme was characterized as a serine protease with 42 kDa molecular weight, stable in a wide range of temperature and pH with maximum keratinolytic activity at 60 °C and pH 9.5. The enzyme had a wide range of different substrates with the best performance on the feather meal substrate. Metal ions of Ca2+, K+, Na+ and Mn2+ enhanced the enzyme activity. The enzyme showed a great deal of stability in the presence of ethanol, methanol, acetone, 2-propanol, dimethyl sulfoxide, Tween-80 and Triton X-100. Dithiothreitol (DTT), as a reducing agent, caused a twofold increase in keratinolytic activity. The half-life of the enzyme at optimum temperature was calculated to be 125 min and the ratio of keratinolytic:caseinolytic for the enzyme was 0.8. Our results showed the remarkable features of the enzyme that make it suitable for biotechnological usages.


Assuntos
Bacillus , Peptídeo Hidrolases , Animais , Bacillus/enzimologia , Concentração de Íons de Hidrogênio , Peptídeo Hidrolases/metabolismo , Especificidade por Substrato , Tensoativos , Temperatura
6.
Iran J Microbiol ; 11(5): 368-372, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32148666

RESUMO

BACKGROUND AND OBJECTIVES: In recent years, reports of Acinetobacter strains resistant to all known antibiotics have caused a great concern in medical communities. Overexpression of efflux pumps is one of the major causes of resistance in bacteria. The aim of this study was to investigate the role of efflux pumps in conferring resistance to imipenem in clinically important Acinetobacter spp; Acinetobacter baumannii and Acinetobacter lwoffii. MATERIALS AND METHODS: A total number of 46 clinical Acinetobacter isolates, including 33 A. baumannii and 13 A. lwoffii isolates, previously collected from Shahid Kamyab and Ghaem hospitals of Mashhad, Iran were used in this study. Imipenem susceptibility testing was carried out by the disc diffusion method. Imipenem minimum inhibitory concentration (MIC) for resistant Acinetobacter isolates were determined both in the presence and absence of the efflux pumps inhibitor, carbonyl cyanide 3-chlorophenylhydrazone (CCCP). RESULTS: Resistance to imipenem was observed in 38 isolates including 30 A. baumannii and 8 A. lwoffii isolates. Experiments in the presence of CCCP showed a 2 to 16384 fold reduction in imipenem MICs in 14 A. baumannii and 2 A. lwoffii isolates. CONCLUSION: The results obtained showed high levels of resistance to imipenem and contribution of efflux pumps in conferring resistance in both Acinetobacter species in this study. Moreover, imipenem efflux mediated resistance highlights the importance of this mechanism not only in A. baumannii but also in non-baumannii Acinetobacter Spp. which have been neglected in antibiotic resistance studies.

7.
Iran J Microbiol ; 10(6): 385-393, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30873266

RESUMO

BACKGROUND AND OBJECTIVES: Traditional culture methods for detection of food-borne pathogens, a major public health problem, are simple, easily adaptable and very practical, but they can be laborious and time consuming. In this study, we eliminated culturing steps by developing a new separation method and therefore, decreased the detection time of food-borne pathogens (Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7 and Listeria monocytogenes) to a few hours. MATERIALS AND METHODS: We used alkaline water and different alkaline buffers to elute bacteria from the lettuce surface as a model for ready-to-eat vegetables. Buffers used were as follows: 1) 0.05 M glycine; 2) 0.05 M glycine -100 mM Tris base -1% (w/v) beef extract; 3) buffer peptone water; 4) buffer phosphate saline. Buffers were adjusted to pH of 9, 9.5 and 10. In order to elute the bacteria, the lettuce pieces were suspended into buffers and shacked for 30, 45 and 60 min. Moreover, a multiplex PCR method for the simultaneous detection of food-borne pathogens was performed. RESULTS: The results showed that buffer peptone water at pH 9.5 for 45 min have high ability to elute bacteria from the lettuce surface and the bacteria can be detected using multiplex PCR. CONCLUSION: We developed a new rapid and efficient method for simultaneous separation of food-borne pathogens. This method eliminates culturing stages and permits the detection and identification of target pathogens in a few hours.

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