فهرست مطالب
Jundishapur Journal of Microbiology
Volume:14 Issue: 4, Apr 2021
- تاریخ انتشار: 1400/05/12
- تعداد عناوین: 8
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Page 1Background
Stomach disorders, including gastric cancer and gastritis, are associated with the pathogenic bacterium Helicobacter pylori. Enhanced inflammation is the characteristic of H. pylori-induced gastritis. Ligustrazine exerts anti-inflammatory properties in mouse asthma models and acute kidney injury.
ObjectivesTo determine the role of ligustrazine in H. pylori-induced gastritis.
MethodsNormal gastric epithelial cell line (GES-1) was cultured with H. pylori at a multiplicity of infection (MOI) of 100: 1 for 24 hours. GES-1 cell line under H. pylori condition was incubated with 100 or 200 μM ligustrazine for 24 hours. Cell viability and apoptosis were investigated by MTT and flow cytometry assays, respectively. Inflammation was assessed by determining the levels and mRNA expression of interleukins (IL)-6/8, tumor necrosis factor-α (TNF-α), and monocyte chemotactic protein 1 (MCP-1) using ELISA and qRT-PCR analysis, respectively.
ResultsHelicobacter pylori infection reduced the viability and promoted the apoptosis of GES-1 cell line, accompanied by the enhanced activities of caspases 3 and 9. However, ligustrazine reversed the H. pylori-induced infection decreased viability, while increased apoptosis and caspases 3/9 activities in GES-1 cell line. Moreover, ligustrazine attenuated H. pylori-induced secretions of pro-inflammatory factors, IL-6/8, TNF-α, and MCP-1, in GES-1 cell line. The protein expression of inhibitor of NF-κB (IκBα) was downregulated in GES-1 cell line after H. pylori infection, while the protein expression levels of p65 and phosphorylation of IκBα were upregulated by H. pylori infection. On the contrary, ligustrazine decreased H. pylori-induced protein expression of IκBα, whereas increased protein expression of p65 and phosphorylation of IκBα.
ConclusionsLigustrazine exerted protective effects on H. pylori-induced gastric epithelial cells through inhibition of gastric inflammation and apoptosis and inactivation of NF-κB pathway.
Keywords: Inflammation, Apoptosis, Helicobacter pylori, NF-κB, Gastritis, Ligustrazine -
Page 2Background
Gram-negative bacilli are primarily responsible for the most common pediatric infections. Frequently, Escherichia fergusonii is identified as E. coli because of its close genetic proximity.
ObjectivesWe aimed at the isolation and identification of multi-resistant strains of E. fergusonii, affecting children under two months of age.
MethodsStrains were isolated from infectious processes and were identified phenotypically and molecularly. The microdilution method (MicroScan, autoSCAN-4) and the disk diffusion method (modified Kirby Bauer) were used to analyze antibiotic susceptibility.
ResultsStrains isolated were multi-resistant. Molecular identification provided the correct taxonomic assignment. Escherichia fergusonii strains were wrongly identified as E. coli with the phenotypic identification method. In addition, Pseudomonas aeruginosa and Klebsiella pneumoniae were identified. The best sensitivity results were obtained with Ceftazidime/avibactam and ceftolozane/tazobactam.
ConclusionsWe provided the first report of isolation and identification of multi-resistant E. fergusonii strains affecting children under two months of age in a neonatal intensive care unit.
Keywords: Antibiotics, Multi-resistant Bacteria, Phenotypic Identification, Molecular Identification, Escherichia fergusonii -
Page 3Background
Aspergillus and Candida species are the most commonly identified fungal pathogens in otomycosis. However, we usually encounter some difficulties in its treatment because many patients show resistance to antifungal agents and present a high recurrence rate.
ObjectivesThe current research was conducted to compare the in vitro activities of luliconazole (LUL), and efinaconazole (EFN) and the nine comparators on Aspergillus and Candida strains isolated from otomycosis.
MethodsThe in vitro activities of nine common antifungal drugs (amphotericin B (AMB), voriconazole (VRC), fluconazole (FLU), itraconazole (ITC), ketoconazole (KTO), clotrimazole (CLO), nystatin (NYS), terbinafine (TRB), and caspofungin (CAS)) and two novel new azoles (LUL and EFN) against of 108 clinical isolates of Aspergillus and Candida species obtained from otomycosis were assessed according to the CLSI broth microdilution document.
ResultsThe LUL and EFN had the geometric mean minimum inhibitory concentrations (GM MICs) of 0.098 and 0.109 μg/mL against all Aspergillus strains, respectively. Furthermore, the GM MICs of all Candida isolates for LUL, EFN, CAS, CLO, VRC, AMB, ITC, KTO, FLU, NYS, and TRB were calculated to be 0.133, 0.144, 0.194, 0.219, 0.475, 0.537, 0.655, 1.277, 4.905, 9.372, and 13.592 μg/mL, respectively. Additionally, 6 (35.29%), 2 (11.7%), and 1 (5.88%) Candida isolates were resistant to FLU, CAS, and VRC, respectively.
ConclusionsAs the findings indicated, LUL and EFN showed the lowest GM MIC values against the examined species. Accordingly, these novel imidazole and triazole antifungal agents can be regarded as proper candidates for the treatment of otomycosis caused by Aspergillus and Candida strains.
Keywords: Antifungal Susceptibility, Otomycosis, Efinaconazole, Luliconazole -
Page 4Background
Hepatitis B Virus (HBV) is a universal health challenge all around the world. Several factors like viral load, genetic characteristics, age, sex, and immune status contribute to variable clinical outcomes of HBV infection. The sequels of HBV infection vary remarkably among persons ranging from the spontaneous deletion of infection to persistent infection.
ObjectiveThe present study aimed to evaluate the association of single nucleotide polymorphisms IL10-1082 with HBV clearance.
MethodsSixty subjects with Chronic Hepatitis B (CHB) infection and 60 subjects who spontaneously recovered HBV were enrolled in the study. The IL-10-1082 polymorphisms were determined by Polymerase Chain Reaction with Restriction Fragment Length Polymorphism (PCR–RFLP).
ResultsThe clearance of HBV infection demonstrated a significant association with IL-10-1082 polymorphisms in the GG genotype (P = 0.03), while there was no association with other genotypes. Reduced risk of chronic hepatitis B infection was associated with IL-10-1082 GG (OR: 2.33, 95% CI: 1.07 - 5.09). Besides, IL-10-1082 A/G alleles did not differ clearly between the two study groups (P = 0.07)
ConclusionsThe IL-10-1082 polymorphisms may be associated with a reduced risk of CHB infection and recovery after HBV infection.
Keywords: Chronic Hepatitis B, Interleukin-10, Single Nucleotide Polymorphism -
Page 5Background
Carbapenem-resistant Acinetobacter baumannii (CRAB) is a significant nosocomial pathogen, causing serious threats concerning community-wide outbreaks globally, as well as in Pakistan. Antimicrobial resistance in A. baumannii is increasing day by day.
ObjectivesThe study aimed to find out the antibiotic resistance (AMR) patterns and evaluate the AMR genes in clinical isolates from patients admitted to the surgical Intensive Care units (ICUs) at different hospitals in Lahore, Pakistan.
MethodsA total of 593 clinical specimens were collected from patients admitted to the surgical ICUs of three different local hospitals in Lahore, Pakistan. From these samples, a total of 90 A. baumannii isolates were identified and further investigated to observe phenotypic resistance patterns and detect carbapenemases resistance genes.
ResultsThe results showed that phenotypic resistance against amikacin was 27.2%, ceftriaxone 100%, ceftazidime 27.2%, cefepime 63.3%, ciprofloxacin and co-trimoxazole 100%, gentamicin 40%, imipenem 22.2%, meropenem 21.1%, piperacillin-tazobactam 27.2%, tigecycline 27.2%, and tetracycline 63.3%. All A. baumannii isolates were found to be sensitive to colistin (CT), polymixin-B (PB), and tobramycin TOB). The PCR amplification of carbapenemases genes revealed the prevalence of blaOXA-23, blaOXA-51, and blaOXA-40 in 73, 90 , and 64.4% of the isolates , respectively, along with blaNDM1 (92.2%), blaVIM (40%), blaIMP (90%), ISAba1 (85.5%), sul1 (16.6%), sul2 (20%), armA (32.2%), and PER-1 (12%) while the blaOXA-24 and blaOXA-58 genes were not detected in the isolates. The sequence analysis of the blaOXA-23 and blaOXA-51 genes showed 98% and 95% similarity with previously reported sequences in the GenBank database.
ConclusionsThe present study indicated that the emergence of high carbapenem resistance in CRAB isolates has increased, which may pose serious limitations in the choice of drugs for nosocomial infections.
Keywords: Nosocomial Infections, Carbapenem-Resistant A. baumannii (CRAB), Hospital-Acquired Infections, blaOXA-51 -
Page 6Background
Staphylococcus aureus is a bacterial pathogen that can cause a wide range of nosocomial infections. Nasal colonization by S. aureus plays an important role both in the epidemiology and pathogenesis of infection.
ObjectivesThis study aimed at detecting the biofilm-forming capacity of clinical isolates and detection of icaA and agr genes.
MethodsA total of 150 clinical specimens was collected from patients in different hospitals in Baghdad. The clinical samples included wounds, abscess, sputum, and ear infections. The suspected isolates were cultured for one day at 37 °C on mannitol salt agar in an aerobic environment.
ResultsThe results showed that of 150 samples, 44 isolates were S. aureus (29.3%), of wounds samples, 22 isolates (45.83%) were S. aureus, 13 (37.14%) were from abscess, 7 (17.95%) from sputum, and 2 isolates (7.14%) from ear samples. This study found that most isolates formed biofilm, but the levels of biofilm were distributed across three ranges. The results also indicated that 47.7% of the isolates produced a strong biofilm, as well as 38.6 and 13.6% produced moderate and weak biofilms, respectively. The present molecular results showed that S. aureus from different samples were 13 (59.1%), 4 (30.77%), 3 (42.85%), 0 (0%) from wounds, abscess, sputum, ear, respectively, were positive for agr gene. While the results showed 18 (81.8%), 10 (76.9%), 5 (71.4%), 1 (50%), respectively, were positive for icaA gene.
ConclusionsMost S. aureus isolates isolated from wound were biofilm positive. These isolates bore icaA and agr genes in a high quantity.
Keywords: Staphylococcus aureus, Virulence Factor, Bacterial Proteins, icaA, agr Genes -
Page 7Introduction
Pyogenic liver abscess (PLA) is a serious infectious disease of the liver. PLA caused by Fusobacterium nucleatum is extremely rare. Here we report the first case of liver abscess caused by F. nucleatum in China.
Case PresentationThe case was a 34-year-old female patient admitted to the hospital due to high fever. The diagnosis of liver abscess was confirmed by imaging studies and liver puncture. We finally confirmed the pathogen as F. nucleatum by next-generation sequencing (NGS). After the targeted anti-infective treatment, the patient recovered and discharged.
ConclusionsAs a new microbial detection method, NGS can still help in clinical practice. In addition, to improve the positive rate of anaerobic bacteria culture, we should pay attention to avoid contact with air in the process of specimen collection when the pathogenic bacteria are suspected to be anaerobic bacteria.
Keywords: Immunocompetent, Pyogenic liver abscess, Next-Generation Sequencing, Fusobacterium nucleatum