Study on the correlation between DPP9 rs2109069 and IFNAR2 rs2236757 polymorphisms with COVID-19 mortality.

Understanding the complex mechanisms of the immune system in dealing with the COVID-19 infection, which is probably related to the polymorphism in cytokine and chemokine genes, can explain the pro-inflammatory condition of patients. Therefore, in this study, the relationship between the frequency of single nucleotide polymorphisms in the two pro-inflammatory genes dipeptidylpeptidase 9 (DPP9) and interferon alpha and beta receptor subunit 2 (IFNAR2) and the severity of COVID-19 was assessed. This study involved 954 COVID-19 patients, including 528 recovered and 426 deceased patients. To investigate the polymorphisms of IFNAR2 rs2236757 and DPP9 rs2109069, we used the polymerase chain reaction with the restriction fragment length polymorphism assay. The results showed that IFNAR2 rs2236757 A allele is related to the reduced severity of the disease, whereas the incidence of DPP9 rs2109069 A allele was higher among the deceased than recovered individuals. On the other hand, in people carrying the G allele in the DPP9 gene polymorphism and the allele A in the IFNR2 gene polymorphism, the improvement of the disease was significantly higher. In conclusion, the results showed that IFNAR2 rs2236757 A allele is related to the decrease in the severity of the disease, while the frequency of DPP9 rs2109069 A allele was higher in deceased people than in recovered people. This shows the important role of genes related to inflammatory responses as well as the role of genetic variants of these genes in the severity of COVID-19.

Molecular Serotyping and Antibiotic Resistance Profile of Group B Streptococcus Strains Isolated from Iranian Pregnant Women with Urinary Tract Infection.

Background: Group B Streptococcus (GBS) can cause serious infections in neonates and pregnant women. GBS may cause urinary tract infections (UTIs). However, molecular epidemiology of such infections is rarely reported. The present study aimed to determine drug resistance patterns and molecular serotyping of GBS isolates in a population of pregnant Iranian women with UTIs. Methods: A cross-sectional study was conducted during the first half of 2021 in the Department of Biology, East Tehran Branch, Islamic Azad University (Tehran, Iran). Sixty GBS strains isolated from the urine and placenta samples of pregnant women with UTIs were evaluated. The women were aged 19-46 years old at 35 to 37 weeks of gestation. The molecular serotype of GBS isolates was determined using a multiplex polymerase chain reaction, and the disc diffusion method was used to determine the antibiotic susceptibility pattern of isolates for different antibiotics. The association of the GBS serotype with the phenotype of antibiotic resistance was statistically analyzed using SPSS software (version 22.0) with a Chi square test and Cramer's V test. P<0.05 was considered statistically significant. Results: GBS capsular serotype II was most prevalent (66.7%) followed by serotypes Ib (21.7%), Ia (3.3%), and III (1.7%). The prevalence of non-typeable isolates was significantly low (6.6%). Of the 60 GBS isolates, 18.3% were resistant to penicillin, 81.6% to ampicillin, 23.3% to clindamycin, and 30% to vancomycin; indicating the need for treatment alternatives. Conclusion: Region-specific information on antibiotic resistance and molecular characteristics of GBS is essential for epidemiological investigations, effective treatment, and vaccine development.

Abundance of extended-spectrum ß-lactamase genes among intestinal Escherichia coli strains from drug users.

Drug users may represent a hidden reservoir of antibiotic resistance genes among their intestinal flora due to the poor hygiene and inappropriate use of antibiotics. Therefore, this study was focused to examine the prevalence of extended-spectrum ß-lactamase (ESBL) genes among intestinal Escherichia coli isolated from drug users in Ahvaz, Iran. Among clients of toxicology laboratory who were confirmed their addiction to each of Morphine, Amphetamine or Methamphetamine, 109 drug users were examined voluntarily for infection with hepatitis B or C using commercial enzyme linked immunosorbent assays (ELISA) method. Their stool specimens were obtained to isolate intestinal E. coli. The disc diffusion and combination disk methods were conducted to demonstrate antibiotic resistance pattern and phenotypically ESBL producers. ESBL-encoding genes (bla-TEM, bla-CTX-M, and bla-SHV) were also examined by PCR. Based on results, hepatitis C infection was more prevalent than hepatitis B among drug users. Of 109 isolates, a total of 57 (52.29%) ESBL positive E. coli were obtained from drug users and bla-TEM gene (60.55%) was found to be the most prevalent type, followed by bla-CTX-M (40.36%) and bla-SHV (39.44%). All isolates represented different resistance levels to tested antibiotics and 54.43% of the ESBL­producing isolates showed multidrug resistance (MDR) and the most frequent MDR pattern was simultaneous resistance to the seven (27.90%) of antimicrobials particularly erythromycin, penicillin, amoxycilin, cefteriaxon, cefotaxim, tetracycline and trimethoprim-Sulfamethoxazole. Fecal carriage of ESBL-production and MDR commensal isolates such as E. coli among drug users underlines the risk of transferring resistance genes between nonpathogenic and pathogenic bacteria.

Recombinant C-terminal 311 amino acids of HapS adhesin as a vaccine candidate for nontypeable Haemophilus influenzae: A study on immunoreactivity in Balb/C mouse.

Hap, an auto-transporter protein, is an antigenically conserved adhesion protein which is present on both typeable and nontypeable Haemophilus influenzae. This protein has central role in bacterial attachment to respiratory tract epithelial cells. A 1000bp C-terminal fragment of Hap passenger domain (HapS) from nontypeable Haemophilus influenzae was cloned into a prokaryotic expression vector, pET-24a. BALB/c mice were immunized subcutaneously with purified rC-HapS. Serum IgG responses to purified rC-HapS, serum IgG subclasses were determined by ELISA and functional activity of antibodies was examined by Serum Bactericidal Assay. The output of rC-HapS was approximately 62% of the total bacterial proteins. Serum IgG responses were significantly increased in immunized group with rC-HapS mixed with Freund's adjuvant in comparison with control groups. Analysis of the serum IgG subclasses showed that the IgG1 subclass was predominant after subcutaneous immunization in BALB/c mice (IgG2a/IgG1 < 1). The sera from rC-HapS immunized animals were strongly bactericidal against nontypeable Haemophilus influenzae. These results suggest that rC-HapS may be a potential vaccine candidate for nontypeable Haemophilus influenzae.