Effect of phenylalanine arginyl ß-naphthylamide on the imipenem resistance, elastase production, and the expression of quorum sensing and virulence factor genes in Pseudomonas aeruginosa clinical isolates.

Pseudomonas aeruginosa is one of the most important nosocomial pathogens that possess the ability to produce multiple antibiotic resistance and virulence factors. Elastase B (LasB) is the major factor implicated in tissue invasion and damage during P. aeruginosa infections, whose synthesis is regulated by the quorum sensing (QS) system. Anti-virulence approach is now considered as potential therapeutic alternative and/or adjuvant to current antibiotics' failure. The aim of this study is primarily to find out the impact of the efflux pump inhibitor (EPI) phenylalanine arginyl ß-naphthylamide (PAßN) on the production of elastase B and the gene expression of lasI quorum sensing and lasB virulence factor in clinical isolates of P. aeruginosa. Five P. aeruginosa isolates recovered from patients with respiratory tract infections were examined in this study. Antimicrobial susceptibility of isolates was performed by the disk agar diffusion method. Effect of the PAßN on imipenem susceptibility, bacterial viability, and elastase production was evaluated. The expression of lasB and lasI genes was measured by quantitative real-time PCR in the presence of PAßN. All isolates were identified as multidrug-resistant (MDR) and showed resistance to carbapenem (MIC = 64-256 µg/mL). Susceptibility of isolates to imipenem was highly increased in the presence of efflux inhibitor. PAßN significantly reduced elastase activity in three isolates tested without affecting bacterial growth. In addition, the relative expression of both lasB and lasI genes was diminished in all isolates in the presence of inhibitor. Efflux inhibition by using the EPI PAßN could be a potential target for controlling the P. aeruginosa virulence and pathogenesis. Furthermore, impairment of drug efflux by PAßN indicates its capability to be used as antimicrobial adjuvant that can decrease the resistance and lower the effective doses of current drugs.

Epidemiology and clinical features of respiratory syncytial virus (RSV) infection in hospitalized children during the COVID-19 pandemic in Gorgan, Iran.

Background and Aims: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory infection in infants and young children. Given the altered circulation patterns of respiratory viruses during the coronavirus disease pandemic-2019 (COVID-19), the study aimed to evaluate epidemiology and clinical features of RSV infections in hospitalized children during the COVID-19 pandemic in Gorgan, northeastern Iran. Molecular epidemiology studies on respiratory viral infections are necessary to monitor circulating viruses, disease severity, and clinical symptoms, in addition to early warning of new outbreaks. Methods: Overall, 411 respiratory swab samples from hospitalized children from October 2021 to March 2022 were collected at Taleghani Children's Hospital, Gorgan, Iran. The incidence of RSV, as well as the circulating subgroups and genotypes, were investigated and confirmed using PCR methods. Additionally, all samples tested for severe acute respiratory syndrome-associated coronavirus 2 (SARS-CoV-2) and influenza, and demographic and clinical data were analyzed using SPSS software. Results: The share of RSV, SARS-CoV-2, and influenza among hospitalized children with acute lower respiratory infections (ALRI) were 27%, 16.5%, and 4.1%, respectively. The RSV subgroup A (genotype ON1) was dominant over subgroup B (genotype BA9), with more severe clinical symptoms. Compared with the prepandemic era there were high numbers of hospitalized SARS-CoV-2 positive children and low numbers of other respiratory viruses. Despite this, the prevalence of ALRI-related RSV-disease among hospitalized children in our specialized pediatric center was higher than COVID-19 disease in the same cohort. Conclusions: Studying the epidemiology of respiratory viruses and determining the circulating strains can contribute to effective infection control and treatment strategies.

Molecular and Serological Epidemiology of Herpes Simplex Virus Type 1 and 2 in Pregnant Women of Gorgan City, North East of Iran.

Background: As one of the most widespread sexually transmitted infections, Herpes Simplex Virus (HSVs) globally account for 60-95% of persistent infections in adults. This infection is prevalent in women of gestational age and is likely to be transmitted from the infected mother to her neonate. Additionally, it gives rise to devastating complications in neonates. This study was designed to estimate the molecular and serological prevalence of HSV-1 and 2 in pregnant women of Gorgan city, North East of Iran. Methods: Vaginal secretions and blood specimens of 315 pregnant women referred to an educational hospital in the North east of Iran were tested for HSV-1 and HSV-2 using multiplex PCR and ELISA assays. Chi-Square test was utilized to evaluate the association of qualitative variables and the level of significance was set at p≤0.05. Moreover, statistical analysis was performed using SPSS V.19.0. Results: HSV-1 and HSV-2 DNA was detected in 5.7% and 8.3% of participants, respectively. Given the serological analyses of total HSV-1 and HSV-2 antibodies, 92.7% (239/315) of patients were IgG positive and 5.4% (17/315) were IgM positive. Conclusion: The rate of HSV-1 and 2 in the present study was lower than that reported by World Health Organization (WHO). This study emphasizes the conduction of further investigations on HSVs since these viruses are probably playing significant role in sexually transmitted infections.

Anti-inflammatory effects of curcumin-loaded niosomes on respiratory syncytial virus infection in a mice model.

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection in paediatrics. While antivirals are apparent candidates to treat RSV-induced diseases, they have not yet met expectations and have remained in infancy. There is growing evidence to suggest that modulating the exacerbated inflammation during RSV infection can improve disease outcome. Curcumin-loaded niosomes have anti-inflammatory effects against RSV-induced respiratory disease by reducing immune cells' infiltration and inflammatory cytokines' production. This study evaluated the effects of curcumin-loaded niosomes on RSV-induced immunopathology in a mice model. Curcumin-loaded niosomes were prepared using the thin-film hydration method and characterized in vitro. Female Balb/c mice were infected by RSV-A2 and treated daily with curcumin-loaded niosomes. The potential anti-inflammatory effects of curcumin-loaded niosomes were evaluated on day 5 after infection. Using curcumin-loaded niosomes decreased immune cell influx and the inflammatory mediators (MIP-1α, TNF-α and IFN-γ) production in the lung, resulting in alleviated lung pathology following RSV infection. These findings indicate that curcumin-loaded niosomes have anti-inflammatory potential and could be a promising candidate to alleviate RSV-associated immunopathology.

Molecular detection of HHV-1, HHV-2, HHV-5 and HBV in semen of fertile and infertile men by multiplex PCR method.

Background and Objectives: A great diversity of factors including viruses such as human herpes virus 1&2 (HHV-1&2), human herpes virus 5 (HHV-5), and hepatitis B virus (HBV) play key roles in sterility and it is worth noting that male infertility accounts for nearly 50% of barrenness, globally. In this regard, we evaluated the prevalence of the aforementioned viruses in semen specimens of two distinct groups of men referred to Novin Infertility Center in Mashhad, Iran. Materials and Methods: In this cross-sectional study, 300 semen samples were collected from 150 infertile and 150 fertile men. Subsequently, genomic DNA was extracted before performing multiplex polymerase chain reaction (PCR). Eventually, the results were analyzed via SPSS Statistics V.16.0. Results: Out of 300 specimens, 183 (61.1%) were positive at least for one of the forenamed viruses; genome detection of HHV-1&2, HHV-5, and HBV were 27%, 18%, 36.66%, and 4%, respectively. Conclusion: The current study found no correlation between infertility and HBV, HHV-5, and HHV-1&2, which may have to do with factors like sample size, the geographical distribution of the viruses, and the lifestyle (sexual behavior) of the participants. These results emphasize the implementation of such studies on a broader scale to determine the exact factors involved in infertility.

Functional variation (Q63R) in the cannabinoid CB2 receptor may affect the severity of COVID-19: a human study and molecular docking.

Evidence supports a role of host genetic diversity in the clinical course of coronavirus disease 2019 (COVID-19). Variation in the cannabinoid CB2 receptor gene (CNR2) could affect the regulatory action of endocannabinoids on the immune system, resulting in an increased risk of various inflammatory diseases. The present study investigated the relationship between the CNR2-Q63R variant and COVID-19 severity. A total of 200 Iranian COVID-19 patients were enrolled in the study and genotyped using a TaqMan assay. The co-dominant, dominant, recessive, over-dominant, and additive inheritance models were analyzed using SNPStats software. In silico molecular docking was also performed to simulate the effects of the Q63R variation on CB2 binding with a ligand and with the G-protein. A significant difference in the Q63R allele and genotype distribution was found between expired and discharged COVID-19 patients in co-dominant, recessive, and additive inheritance models. The molecular docking results showed that the predicted structure of mutant CB2 (63R type) could not bind to the G-protein in the correct position. The data indicated that the Q63R variation in the CNR2 gene may affect the severity of COVID-19. Identification of genes related to susceptibility and severity of COVID-19 may lead to specific targets for drug repurposing or development.

CRISPR-Cas systems in Proteus mirabilis.

The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) is a bacterial defense mechanism against bacteriophages composed of two different parts: the CRISPR array and the Cas genes. The spacer acquisition is done by the adaptation module consisting of the hallmark Cas1 Cas2 proteins, which inserts new spacers into the CRISPR array. Here we aimed to describe the CRISPR-Cas system in Proteus mirabilis (P. mirabilis) isolates. CRISPR loci was observed in 30 genomic contents of 109 P. mirabilis isolates that each locus was consisted of two CRISPR arrays and each array had a different preserved leader sequences. Only the type I-E CRISPR-Cas system was common in these isolates. The source of the spacers was identified, including phages and prophages. CRISPR spacer origin analysis also identified a conserved PAM sequence of 5'-AAG-3' nucleotide stretch. Through collecting spacers, CRISPR arrays of P. mirabilis isolates were expanded mostly by integration of bacteriophageal source of spacers. This study shows novel findings in the area of the P-mirabilis CRISPR-Cas system. In this regard, among analyzed genome of P. mirabilis isolates, Class I CRISR-Cas systems were dominant, and all belonged to type I-E. In the flanks of the CRISPR, some other elements with regulatory role were also found. A motif of 11 nt size was found to be preserved among the analyzed genome. We believe that it might has a CRISPR-Cas system transcription facilitator by targeting the Rho element.