International Journal of Molecular and Clinical Microbiology
Year:2023 | Volume:13 | Issue:2|Papers Count:10

Mucormycosis is a severe and potentially fatal fungal infection caused by opportunistic fungi belonging to the class Zygomycetes. Coronavirus 2019 (COVID-19) is a severe worldwide disease. One of the problems faced by Covid-19 patients is concurrent infection with microbial agents such as life-threatening fungal infections. Studies show that people with diabetes who have recovered from COVID-19 are more likely to develop mucormycosis. In addition, patients with COVID-19 are at increased risk of acute heart damage, arrhythmias, thromboembolic complication, and secondary infection. However, the exact reasons and mechanisms of increasing this deadly infection need to be investigated to understand the pathogenicity and discover reasonable ways of prevention and treatment. Studies show that increasing overuse of steroids, antibiotics, and zinc as an act of self-medication during the Covid-19 epidemy may increase intestinal microbiota dysbiosis, thereby suppressing the system—immunity in the group at risk of this fungus. Ocular and cerebral mucormycosis is the most common form of the disease, with a mortality rate of over 49%, especially in patients with pulmonary or diffuse or cerebral mucormycosis. In addition, a significant proportion of survivors of the disease showed symptoms such as 46% vision loss. This article addresses potential mechanisms, host-related factors, pathogenicity, and innate and acquired immune system responses that may help understand the mystery of the sudden, severe, and fatal increase in mucormycosis infections due to Covid-19. Early detection of such conditions with the above-mentioned consequences is vital for optimal treatment and better results.

Infection by carbapenem-resistant strains of Klebsiella pneumoniae is a life threating problem in hospitals. Capsule and fimbriae are known as important virulence factors of Klebsiella pneumoniae. The aim of this study was to investigate the prevalence of two genes coding capsule (wabG) and fimbriae (fimH) in carbapenem-resistant Klebsiella pneumoniae strains isolated from patients hospitalized in Isfahan, Iran. The susceptibility of the isolates to carbapenem was evaluated by disk diffusion. Definitive confirmation of carbapenem resistant isolates was done through 16S-23S ITS gene; and finally, carbapenem resistant (OXA48), capsule (wabG), and fimbriae (fimH) genes were traced in the isolates. The data were analyzed using independent parametric T test and one-way analysis of variance (ANOVA). Out of 102 clinical isolates, 50 isolates (49%) were carbapenem resistant and 52 isolates (51%) were sensitive to carbapenem. The most carbapenem-resistant isolates were isolated from the ICU (42%) and emergency departments (22%). All carbapenem resistant isolates had OXA48 gene. Out of 50 isolates with carbapenem resistance gene, 48 isolates (96%) had fimH gene and 47 isolates (94%) had wabG gene. Most carbapenem resistant isolates with fimH were from men (31 isolates), and from respiratory trachea (31%) and urine (27%). Most carbapenem resistant isolates with wabG were from men (29 isolates), and from respiratory trachea (28%) and urine (30%). High frequency of carbapenem resistance in Klebsiella pneumoniae isolate and the high frequencies (more than 90%) of fimH and wabG genes which is higher than many previous reports is significant and should be considered in diagnostic and treatment protocols.

Heterocycles containing nitrogen element show many medicinal properties. Among them, triazoles show significant anticancer and antifungal properties. Because of the useful properties of these compounds, chemists have always been looking for an easier and more effective way to synthesize these compounds. In this study, ten novel 3-aminoaryl -5-aryl-1,2,4-triazoles derivatives were prepared via the reaction of N-acyl-N′-aryl thioureas and hydrazine hydrate in the reflux conditions and characterized by analytical and spectral analyses. In this study, the antibacterial properties of the compounds synthesized by the well diffusion method were investigated. All compounds showed good antibacterial properties against Staphylococcus aureus and Escherichia coli bacteria. Compounds 3g, 3f and 3j had the most antibacterial effect.

Listeriosis (caused by Listeria monocytogenes) is one of the most serious and severe foodborne diseases. The purpose of present study is to investigate the antibacterial, antiinvasion and anti-adhesion effect of synthesized Ag-doped ZnO (ZnO:Ag NPs) nanoparticles against L.monocytogenes isolates. ZnO and ZnO:Ag NPs were synthesized using a chemical method and were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Energy Dispersive X-ray (EDX) and Fourier-transform infrared (FTIR) spectroscopy. Antibacterial assay of nanoparticles towards L. monocytogenes was performed using culture turbidity measurement. The MTT assay was performed for assessing cytotoxicity activity in Caco-2 cells exposed to L.monocytogenes treated with 3.125, 6.25, 12.5, 25, 50 and 100 μg /ml concentrations of both ZnO and ZnO:Ag NPs. The adhesion and invasion assays were performed by infecting semiconfluent Caco-2 cell monolayers grown in 24-well plates. To further confirm, the messenger RNA (mRNA) levels of invasion and adhesion‐associated genes (inlA, hlyA and prfA) of L. monocytogenes were examined using Real-time PCR. Our results show ZnO:Ag NPs have great antibacterial activities against L.monocytogenes isolates. Paper results also indicated exposure of L.monocytogenes isolates treated with all concentration of ZnO:Ag NPs could obviously reduce the viability of Caco-2 cells. The results of Realtime PCR revealed that the mRNA levels of inlA, hlyA and prfA were dramatically downregulated after the exposure of L.monocytogenes treated with ZnO:Ag NPs compared to 16S rRNA as housekeeping gene. It can therefore be considered that ZnO:Ag NPs should be utilized in medicinal and pharmaceutical applications as credible antibacterial, anti-invasion and anti-adhesion agents.

Prostate cancer is one of the most common kinds of malignancy in men, with a significant morbidity and mortality rate. The aim of this research is to investigate the effects of Cpe on the expression of bak, bax, fas, bcl2, cyclin D1, and cyclin E genes on DU145 prostate cancer cell lines. In the present study, the pBudCE4.1-CPE recombinant vector and empty plasmid were individually transformed into the DU145 cell line using the Lipofectamine 2000 protocol. The presence of each vector was checked by PCR. The cpe gene expression in transfected DU145 was assessed. Expression of apoptotic genes (fas, bcl2, bak, and bax) and cell cycle progression genes (cyclin E and cyclin D1) was maintained in transfected and untransfected DU145 cells. Statistical analyses revealed that the expression of bak, bax, and fas were considerably higher in cells transfected with a recombinant vector (P < 0.05). bcl2 and cyclin E and cyclin D1 genes expression decreased significantly in vector transfected DU145 cells when compared with the cells transfected by an empty plasmid or untransfected ones. Cpe expression could suppress DU145 growth by affecting cell apoptosis. The expression of cpe in the DU145 cell line was tested for the first time and confirms its probable effect on similar cells. According to the findings of this study, cpe gene in a recombinant vector might be a candidate vaccine for the treatment of prostate cancer.

Although little research has been conducted on the role of Streptococcus pyogenes superantigens in psoriasis, exploring this area could lead to valuable insights and potential treatment options for individuals with psoriasis. This study aimed to assess the presence of superantigens, including SpeK, SpeL, SpeM, SpeC, and SmeZ, in plaque samples from Iranian medical centers and to examine any changes in their expression after gliotoxin treatment. Skin plaque samples were collected from 400 50-year-old patients using swabs. The presence of superantigens was determined using the multiplex PCR method. Streptococcus pyogenes strains were confirmed using a specific primer SPY1258, and gene expression after gliotoxin treatment was assessed using real-time PCR. According to our data, among 400 samples, 50 were found to contain Streptococcus pyogenes. The analysis further revealed that SpeK and SpeL were present in these samples with 50% and 8% prevalence, respectively. These were mostly found in samples collected from patients with hand lesions.. Additionally, there was a significant decrease in the expression of these two genes after gliotoxin treatment. However, there was no evidence of the presence of the other three genes. These findings suggest that microbial toxins, such as gliotoxin, can potentially be utilized to develop antimicrobial drugs for treating psoriasis. Therefore, further research should be conducted to explore the potential of gliotoxin as a treatment option for psoriasis

Isolation, identification and selection of the best Lactobacillus with probiotic activity from local dairy products of Gilan province. In this study, 30 isolates obtained from local dairy products in rural areas of Gilan were identified microbiologically and biochemically. The probiotic characteristics of the strains were determined and antagonistic activity of the extract of Lactobacillus isolates against five pathogenic bacteria by the well method in agar, and antibiogram by the disk diffusion method and finally the isolates were identified based on the 16SrRNA sequence. Among the isolates, four strains with the best results in terms of probiotic performance were identified. In the investigation of antimicrobial activity, the isolates were able to inhibit the growth of Staphylococcus aureus, Shigella flexneri, Pseudomonas aeruginosa and Uropathogenic Escherichia coli, but they had no significant inhibitory effect on the growth of Bacillus cereus. Antibiogram results showed that all four strains were resistant to vancomycin and gentamicin but sensitive to ampicillin. None of the isolates showed hemolytic activity. Only two strains showed a clear band in the genomic analysis of 16srRNA by PCR method. The affinity of the strains indicated Lactobacillus delbrueckii subspecies bulgaricus. The extract of these two strains without neutralization and catalase enzyme showed the best activity against common pathogenic bacteria. According to the available results, our strain can be used as a suitable candidate as a supplement in the prevention and biological treatment of some clinical cases in laboratory and in vivo conditions with further research.

Treatment of diarrhea caused by bacteria is a progressing phenomenon in which probiotics play an essential role. The aim of this study is to investigate the antibacterial effect of the probiotic Bacillus subtilis natto on a number of common pathogens of the digestive system. In this study, Bacillus subtilis natto ATCC G8S3 strain was selected as a probiotic and its antimicrobial effect on four gastrointestinal pathogens including Bacillus cereus ATCC 11778, Salmonella typhimurium ATCC 1429, Shigella flexneri ATCC 11222 and Escherichia coli ATCC 25922 was investigated. In order to detect the antimicrobial activity of Bacillus subtilis natto, various methods such as agar well diffusion, disc diffusion, MIC and MBC were used based on microbiology standards and with four replications. In the agar well diffusion method, among the four pathogens, Bacillus subtilis natto showed an antimicrobial effect only on the pathogen Escherichia coli, a non-growing halo with a diameter of 10 mm but this probiotic did not show antibacterial effect on Bacillus cereus, Salmonella and Shigella pathogens. In the disk diffusion method, Bacillus subtilis natto did not show antimicrobial effect on any of the pathogens of this research. MIC for Escherichia coli pathogen was 50, while no antibacterial effect was observed on Bacillus cereus, Salmonella and Shigella pathogens. MBC results showed that this probiotic had no lethal effect on the studied bacteria. Bacillus subtilis natto ATCC G8S3 is safe and resistant as a probiotic and it was able to show inhibitory results on Escherichia coli pathogen.

Pseudomonas aeruginosa, a versatile pathogen causing a wide range of infections, faces escalating resistance to conventional antibiotics, necessitating exploration of alternative substances. Plant extracts and essential oils, known for potent antibacterial compounds, emerge as promising candidates to combat P. aeruginosa effectively. Essential oil from Pistacia atlantica gum was extracted using a Clevenger apparatus, and Camellia sinensis (green tea) extract was obtained through maceration. Gas chromatography/mass spectrometry (GC-MS) and spectrophotometry identified compounds in the essential oil and extract. Antibacterial properties were assessed using the microdilution technique, and synergistic effects of combined substances were evaluated through the modified checkerboard method, utilizing the Fractional Inhibitory Concentration (FIC) index. P. aeruginosa (ATCC27853) was the target bacteria. Alpha-pinene and polyphenols were identified as predominant compounds in P. atlantica gum essential oil and C. sinensis extract, respectively. Both compounds exhibited comparable Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values, at 625 and 1250 μg/ml, respectively. The FIC index calculation for the combination of essential oil and extract demonstrated enhanced antibacterial activity against P. aeruginosa. Results affirm the inhibitory and bactericidal properties of P. atlantica gum essential oil and C. sinensis extract against P. aeruginosa. Concurrent use exhibited synergistic antibacterial effects. This study suggests that these natural compounds, especially when combined, could serve as potent agents in the battle against P. aeruginosa infections, offering a potential avenue for the development of alternative antimicrobial strategies.

The result showed the maximum resistance for imipenem (100%), meropenem (100%), cefotaxime (98.6%), and ceftazidime (98.6%), and minimum resistance for tetracycline (65.7%) and gentamicin (68.6%). The MCBT test for meropenem-gentamicin-tetracycline antibiotics demonstrated 65.6% and 6.3% of MDR Acinetobacter baumannii strains killed at high and low concentrations of antibiotics, respectively (P=0.04). Besides, 34.4% and 93.8% of MDR Acinetobacter baumannii strains lived at high and low concentrations of meropenem-gentamicin-tetracycline antibiotics, respectively, which were statistically significant (P=0.04). There was a significant relationship between the MIC of gentamicin-meropenem in the combination (Checkerboard) (P=0.0001). Antibiotic interaction effects frequencies were 6.3%, 53.1%, and 40.6% for synergy, incremental, and indifference, respectively. In this study, a significant difference was shown between the FICIs of meropenem (0.68±0.27) and gentamicin (0.003±0.003) (P=0.0001). Also, there was a significant correlation between the FICI factor and the antibiotic's antimicrobial interaction by MCBT (r=0.95, P=0.0001).Conclusion: It seems that the combination of meropenem-gentamicin-tetracycline antibiotics had additive antibacterial effects and could be used to suppress MDR Acinetobacter baumannii isolated.