فهرست مطالب

Jundishapur Journal of Microbiology - Volume:12 Issue: 3, Mar 2019

Jundishapur Journal of Microbiology
Volume:12 Issue: 3, Mar 2019

  • تاریخ انتشار: 1398/01/26
  • تعداد عناوین: 8
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  • Maryam Zangi , Azam Bakhshandeh , Masoumeh Mehrpouya , Majid Shahbazi * Page 1
    Background
    The most common primary cause of liver cancer is hepatocellular carcinoma (HCC). Cytokines as mediators have significant roles in immune and inflammatory responses. Interleukin-13 (IL-13) is a potent pleiotropic cytokine.
    Objectives
    The aim of this study was to evaluate the association of IL-13/+110 gene polymorphism in patients with chronic hepatitis B virus (HBV), one of the most important factors that lead to the development of HCC.
    Methods
    DNA was extracted from peripheral blood cells of all 585 participants including 302 unrelated Hepatitis B surface antigen (HBS-Ag) positives and 283 healthy matched groups. The IL-13 gene polymorphism (+ 110 A or G) was genotyped by SSP-PCR method and then genotype frequencies were checked by using the Pearson’s chi-square test and/or Fisher exact test.
    Results
    The frequencies of A/G genotype (CI = 1.18 - 2.34, OR = 1.66, P = 0.004) and A/A genotype (CI = 0.95 - 3.53, OR = 1.84, P = 0.071) were higher in the patients. Also, the frequency of A allele was remarkably higher in the HBV patients than control group (CI = 1.09 - 1.79, OR = 1.84, P = 0.071).
    Conclusions
    High frequency of A allele in patients rather than control group suggested that A allele probably plays a role in augmenting susceptibility to HBV infection risk and high frequency of G allele in controls suggested this allele has a protective role in this disease.
    Keywords: Hepatitis B Virus (HBV)_Hepatocellular Carcinoma (HCC)_Interleukin-13_Polymerase Chain Reaction (PCR)_Polymorphism
  • Juan Carlos Bravata, Alcantara , Juan Manuel Bello, Lopez , Iliana Alejandra Cortes, Ortiz , Juan Jose Mendez, Velazquez , Brandon Aviles, Soto , Laura Itzel Quintas, Granados , Sonia del Carmen Chavez, Ocaa , Cecilia Rosel, Pech , Juan Antonio Gonzalez, Barrios , Monica Sierra Martinez * Page 2
    Background
    The causative primary agent of urinary tract infections (UTI) is uropathogenic Escherichia coli (UPEC); however, commensal Escherichia coli (CEC) has been also implicated in the development of UTI. Due to the recent emergence of virulent and resistant strains, it is necessary to have evidence to demonstrate that UPEC and CEC are isolated from patients with UTI and subsequently they have the genes to be considered pathogenic.
    Objectives
    To determine the distribution of resistance and virulence genes in UPEC and CEC strains isolated from the patients with UTI (hospitalized and ambulatory).
    Methods
    One hundred seven E. coli strains were genotyped according to Clermont protocol and were subjected to PCR assays in order to detect resistance and virulence genes. In addition, the antimicrobial test in solid media was performed to determinate the correlation “pheno/genotype”.
    Results
    Genotyping analysis showed that group B2 (42.05%) was the most predominant, strains followed by A (27.1%), D (24.29%), and finally, B1 (6.54%). β-lactams, carbapenems, aminoglycosides, and nitrofurans showed the best activity. The virulence gene frequencies were: fimH (92/85.98%), iutA (68/63.55%), traT (66/61.68%), papC (36/33.64%), and cnf1 (15/14.02%) while resistance genes were: blaCTX-M(41/38.32%), blaOXA (49/45.79%), and blaSHV (2/1.87%). The associations fimH/blaCTX, fimH/blaOXA, traT/blaCTX, traT/blaOXA, iutA/blaCTX, and iutA/blaOXA showed higher incidence while the associations with cnf1 and papC genes were low.
    Conclusions
    Uropathogenic E. coli has the necessary genetic elements (virulence and resistance) to be considered the main pathogen causing UTI in the Mexican population. Additionally, to our knowledge, there are no studies in our country demonstrating that the CEC isolated from the patients with UTI contains genetic elements of virulence and resistance that allow them to be potentially pathogenic.
    Keywords: Virulence, Antimicrobial Resistance, Escherichia coli, Urinary Tract Infection
  • Rasha Aldasouqi , Luay F. Abu, Qatouseh , Eman F. Badran , Sameer A. Alhaj Mahmoud , Rula Madhat Darwish * Page 3
    Background
    Fusidic acid-resistant Staphylococcus aureus (FRSA) has been reported in many countries to have a remarkable difference in resistance determinants. Fusidic acid resistance is very important because it might lead to the failure of topical treatment, especially when it is used as empiric therapy. In addition, its resistance might be linked to other antibiotic resistances. The overall rate of fusidic acid resistance is still relatively low. However, there is an increase in the prevalence of clinical isolates of FRSA worldwide.
    Objectives
    We aimed to characterize FRSA isolated from Jordanian patients and evaluate the occurrence of the genetic resistance caused by fusB and fusC.
    Methods
    We conducted a prospective cross-sectional study to determine the prevalence and the resistance pattern of S. aureus to fusidic acid among Jordanian patients and healthy people. Staphylococcus aureus clinical isolates (n = 113) obtained from patients admitted to Prince Hamzah Hospital between February and July 2015 were compared with isolates (n = 288) obtained from healthy subjects. Conventional methods were used for the identification of S. aureus and further confirmations were done by the existence of the thermonuclease gene using polymerase chain reaction (PCR). Screenings of antibiotic resistance were performed using the disc diffusion method. The minimum inhibitory concentrations were calculated using the E-test. PCR was used to detect the presence of resistant genes.
    Results
    The FRSA frequency was significantly higher among clinical isolates (31.9%) than among isolates from healthy subjects (1%) and in methicillin-resistant Staphylococcus aureus (MRSA) (66.7%) than in methicillin-sensitive Staphylococcus aureus (MSSA) (33.3%). Of the FRSA isolates, 38.9% and 16.7% carried fusB and fusC, respectively, and they displayed low resistance compared to non-fusB, non-fusC FRSA isolates. The rate of FRSA was significantly (P < 0.05) higher among MRSA than among MSSA isolates (n = 24, 66.7% and n = 12, 33.3%, respectively). We found no association between fusidic acid determinants among MRSA and MSSA (P > 0.05).
    Conclusions
    A high occurrence of FRSA was detected in Jordanian clinical isolates of S. aureus, particularly among MRSA. Moreover, fusB was the predominant resistance determinant, with low-level resistance. Based on our findings, fusidic acid susceptibility testing is strongly recommended in medical laboratories. The restricted use of fusidic acid is advised.
    Keywords: Staphylococcus aureus, Fusidic Acid, Drug Resistance, fusB, fusC Genes
  • Shahroz Khan *, Ijaz Ali , Malik Badshah , Qaiser Mohammad Khan , Zahida Nasreen Haider , Sajid Ali , Imtiaz Ali Khan , Anwar Ullah Page 4
    Background
    A number of studies on the distribution of hepatitis C virus (HCV) genotypes among the chronically HCV-infected people have reported different patterns from various geographical regions of Pakistan. A relatively large scale epidemiological study was needed in order to figure out the distribution pattern of HCV genotypes.
    Objectives
    This research study was carried out to investigate the distribution pattern of hepatitis C virus genotypes in different geographical regions of Pakistan.
    Methods
    In the current study, 5259 randomly selected patients with different genders, ethnicity, age groups, belonging to 24 geographical locations of Pakistan were included. Blood samples from patients with a positive history of active HCV infection were collected from various healthcare units from February 2016 to September 2018. Hepatitis C virus RNA was detected in serum samples by qualitative PCR and confirmed by real-time PCR. Hepatitis C virus genotyping analysis was performed by type specific PCR.
    Results
    Our study revealed that out of 5259 HCV infected patients, HCV genotype 3a was the most frequent one (n = 4203, 79.9%) in all of the 24 regions of Pakistan, especially in Rawalpindi and Islamabad (Twin cities). Untypeable genotype (n = 415, 7.9%) was the second most frequent one after 3a followed by 3a3b co-infection (n = 355, 6.7%), 3b (n = 182, 3.5%), 2a (n = 92, 1.7%), 2b (n = 10, 0.2%), and 1b (n = 2, 0.03%). Interestingly, rarely detectable genotype 4 (n = 1, 0.01%) was also reported. The overall distribution pattern of HCV genotypes was the same in both the genders. Comparatively higher HCV chronic infection was reported among patientwith age group (41 - 55).
    Conclusions
    Currently the existing distribution pattern of HCV genotypes in Pakistan is similar to slight variations in some regions. Comparative analysis of the HCV genotype distribution indicated that the dynamics of HCV genotypes has changed in different areas with the emergence of a relatively uniform pattern across the country.
    Keywords: Epidemiology_Hepatitis C Virus_Genotypes_Chronic Infection_Pakistan
  • Neda Kiasat, Ali Rezaei, Matehkolaei, Ali Zarei Mahmoudabadi *, Khadijeh Hamidavi Mohamadpour , Shahla Molavi , Nastaran Khoshayand Page 5
    Background
    Candida vaginitis or vulvovaginal candidiasis (VVC) is the most common mucosal infection of the female genital tract caused by different species of Candida. Despite several antifungal therapies and personal hygiene practices, VVC has remained an important public health problem affecting millions of women worldwide.
    Objectives
    The aim of this study was to determine the prevalence of VVC and the frequency of causative agents in women of different age groups referring to the midwifery clinics in Ahvaz, Iran, from January 2017 to March 2018.
    Methods
    Samples were obtained from 493 women aged 15 - 64 years with signs and symptoms of VVC using endocervical swabs. All collected samples were cultured on CHROMagar Candida plates and incubated at 35°C for 24 - 72 h. Various Candida sp. were initially identified using morphologic characteristics and physiologic features, and finally confirmed with PCR-RFLP.
    Results
    Totally 196 (39.76%) cases were diagnosed as VVC, of which nine (4.6%) were as recurrent vulvovaginal candidiasis. More than half of the cases were in the age group of 21 - 30 years. Candida albicans was the most commonly identified species (71.1%), followed by C. glabrata (20.4%) and other non-C. albicans species (8.6%). Infection in pregnant women decreased in the third trimester compared to the first and second trimesters of pregnancy.
    Conclusions
    Vulvovaginal candidiasis is a relatively common gynecologic problem in Ahvaz. Although the frequency of non-C. albicans species in VVC has increased, C. albicans is still the predominant species.
    Keywords: Candida albicans, Non-albicans Species, Vulvovaginal Candidiasis
  • Ayaz Anwar , Samina Perveen , Shakil Ahmed , Ruqaiyyah Siddiqui , Muhammad Raza Shah , Naveed Ahmed Khan * Page 6
    Background
    Nanomaterials-based antibacterial agents are anticipated as future generation antibiotics. Silver nanoparticles are promising candidates to enhance the antibacterial effects of antibiotic drugs and lead compounds. Pyridine compounds and thiol moieties are important classes of pharmacophores that are part of many drugs used against numerous diseases; therefore, we conjugated synthetic thiopyridine (ThPy) with silver nanoparticles.
    Objectives
    The study was designed to evaluate the antibacterial potential of ThPy and the effects of silver nanoparticles conjugation with it and to explore the synergistic effects of other metal ions.
    Methods
    Using formyl pyridine reaction with dibromopropane, N-alkylated product was obtained. Bromo group was substituted by thioacetate nucleophile resulting in the formation of thiopyridine (ThPy). Thiopyridine was used to stabilize silver nanoparticles synthesized by one-phase reduction. Silver nanoparticle-conjugated thiopyridine (ThPy-AgNPs) showed typical surface plasmon resonance band, while atomic force microscopy (AFM) showed size and morphology of spherical polydispersed nanoconjugates of 60 nm.
    Results
    Antibacterial properties of synthesized cationic compound thiopyridine was enhanced by conjugation with silver nanoparticles. Moreover, we presented a new strategy in which thiopyridine-AgNP nanoconjugates’ affinity towards copper ions is utilized to further enhance antibacterial activity of nanoconjugates. ThPy-AgNPs exhibited more inhibitory effects against Escherichia coli (MIC of 100 µg/mL compared to 200 µg/mL with ThPy). Nanoconjugates showed selective affinity for Cu(I) ions to cross the E. coli membrane.
    Conclusions
    The addition of Cu(I) ions with ThPy-AgNPs has a synergistic effect on the activity of nanoconjugates against E. coli. Atomic force microscopy is proved to be an excellent choice to study the morphological changes occurring during the antibacterial process.
    Keywords: Thiopyridine, Silver Nanoparticles, Antibacterial Activity, Synergistic Effects, Escherichia coli, Atomic Force Microscopy
  • Masanobu Hiraoka , Gen Sugita , Mehmet Gunduz , Esra Gunduz , Shunji Tamagawa , Masamitsu Kono , Saori Takeda , Noboru Yamanaka, Muneki Hotomi * Page 7
    Background
    Nontypeable Haemophilus influenzae (NTHi)-caused acute otitis media persists even after antimicrobial treatment, presumably as a result of biofilm formation. It is urgent to establish an alternative antimicrobial treatment against acute otitis media that effectively deals with NTHi biofilm.
    Methods
    An otopathogenic clinical strain of NTHi IH-202 isolated from the middle ear fluid of intractable pediatric cases of acute otitis media was used in the study. Antimicrobial susceptibility and biofilm assay using antimicrobial agent tosufloxacin were performed.
    Results
    Exposure to tosufloxacin at 0.96 µg/mL for 20 minutes reduced the amount of NTHi biofilm formation and killed viable NTHi in biofilm as compared with the control. A clinically attainable concentration of tosufloxacin could destroy NTHi biofilm and showed bactericidal activity against NTHi in biofilm in shorter exposure periods.
    Conclusions
    The current findings suggest an alternative antimicrobial treatment strategy against intractable cases of acute otitis media caused by NTHi biofilms. Tosufloxacin will be an effective alternative for the treatment of intractable acute otitis media caused by NTHi biofilm. In addition, our in vitro bacteria-epithelial cell co-culture model is a relatively simple and static method for studying NTHi biofilms.
    Keywords: Nontypeable Haemophilus influenzae, Tosufloxacin, Biofilm
  • Yunhui Fang , Yunbo Chen , Silan Gu , Xuewu Zhang , Tao Lv , Qiaomai Xu , Wei Yu , Jiazheng Quan , Lanjuan Li * Page 8
    Introduction
    Clostridium difficile infection always manifests as diarrhea associated with antibiotic use. Nevertheless, extraintestinal infections caused by C. difficile are reported. The current report was on a case of C. difficile bacteremia in a 51-year-old male patient with appendiceal perforation and abscess as well as confirmed cirrhosis.
    Case Presentation
    The patient was admitted to the infectious diseases department with repeated abdominal pain associated with fever. His anaerobic blood culture was positive for C. difficile two days after transarterial chemoembolization. The same toxin strain was isolated from stool four days later. Both of the two isolates were confirmed positive for toxin A (tcd A) and toxin B (tcd B) genes by polymerase chain reaction, and identified as ST3 by multiple locus sequence typing. The two strains showed the same susceptibility to the tested antibiotics. The patient was treated with vancomycin intravenously, and got remitted shortly after that. The patient was discharged with good general health conditions and followed up.
    Conclusions
    A patient with C. difficile bacteremia presenting with appendiceal perforation and abscess as well as confirmed cirrhosis was described, and the microbiological and molecular biological analysis suggested that C. difficile strains isolated from blood came from gut. It is necessary that clinicians detect C. difficile and/or toxins in patients with long terms antibiotic therapy, in case of transformation of intestinal flora, which could cause the infection outside the intestinal tract.
    Keywords: Clostridium difficile, Bacteremia, Liver Cirrhosis, Appendix, Perforation