Prevalence and Resistance Profiles of Pediatric Enterococcal Isolates: A Five-Year Update from Children's Medical Center Hospital, Tehran.

Background: In this study, attempts were made to evaluate the frequency of high-level gentamicin-resistant (HLGR) and vancomycin-resistant enterococci (VRE) and the prevalence and antibiotic resistance profile of enterococcal species isolated from pediatric patients referred to Children's Medical Center Hospital, Tehran, over five years.

Materials And Methods: A total of 404 enterococcal isolates from different patients referred to the Children's Medical Center between March 2016 and March 2021 were included in this cross-sectional study. Antimicrobial susceptibility testing was performed using standard methods according to the guidelines of the Clinical Laboratories Standards Institute (CLSI).

Sub-minimum inhibitory concentrations (sub-MICs) of colistin on biofilm formation potency, adherence, and invasion to epithelial host cells: an experimental study in an Iranian children's referral hospital.

Here, we described the efficacy of colistin sub-minimum inhibitory concentrations (sub-MICs) on biofilm-forming activity, host epithelial cell adherence, and invasion capacity of strains collected from children admitted to the Children's Medical Center Hospital. Biofilm formation potency of clinical isolates was measured using a 96-well microtiter plate assay. Distribution of biofilm-related genes, including , , , , and , was detected by PCR.

Invasion of HeLa Cells by Species Clinical Isolates Recovered from Pediatric Diarrhea.

is considered a major public health concern, especially for children younger than 5 years of age in developing countries. The pathogenicity of is a complex process that involves the interplay of multiple genes located on a large, unstable virulence plasmid as well as chromosomal pathogenicity islands. Since various factors (including virulence and antibiotic resistance genes) are associated with the severity and duration of shigellosis, in this article, we aim to evaluate whether the invasion of HeLa cells is affected by spp.

Serotypes: O-antigen Structure, Serotype Conversion, and Serotyping Methods.

is the most common cause of shigellosis in developing countries. Up to now, 23 serotypes of S. have been reported.

The inhibitory effects of live and UV-killed Akkermansia muciniphila and its derivatives on cytotoxicity and inflammatory response induced by Clostridioides difficile RT001 in vitro.

Clostridioides difficile infection (CDI) is the leading cause of healthcare-acquired infections worldwide. Probiotics are widely recommended to prevent CDI and its recurrences. Akkermansia muciniphila, as a therapeutic symbiont colonizing the intestinal mucosal layer, is considered to be a promising next-generation probiotic.

Molecular Characterization of Resistance to Second-Line Anti-Mycobacterial Drugs among Clinical Isolates of Multidrug-Resistant Mycobacterium tuberculosis.

Background: The emergence of multidrug resistance and extensively drug-resistant tuberculosis is a serious public health crisis. Using rapid and inexpensive molecular methods such as HRM assay in the detection of second-line drugs resistance in M. tuberculosis would be helpful in the treatment and control of XDR tuberculosis cases.

Anti-virulence therapeutic strategies against bacterial infections: recent advances.

The emergence and increasing prevalence of multidrug-resistant pathogens has become a major global healthcare problem. According to the World Health Organization if these trends continue, mortality from infection in 2050 will be higher than that from cancer. Microorganisms have various resistance mechanisms against different classes of antibiotics that emphasize the need for discovery of new antimicrobial compounds to treat bacterial infections.

Surface layer protein A from hypervirulent Clostridioides difficile ribotypes induce significant changes in the gene expression of tight junctions and inflammatory response in human intestinal epithelial cells.

Background: Surface layer protein A (SlpA), the primary outermost structure of Clostridioides difficile, plays an essential role in C. difficile pathogenesis, although its interaction with host intestinal cells are yet to be understood. The aim of this study was to investigate the effects of SlpA extracted from C.

Acinetobacter baumannii: Pathogenesis, virulence factors, novel therapeutic options and mechanisms of resistance to antimicrobial agents with emphasis on tigecycline.

What Is Known And Objective: Acinetobacter baumannii is one of the most important nosocomial pathogens with the ability to cause infections such as meningitis, pneumonia, urinary tract, septicaemia and wound infections. A wide range of virulence factors are responsible for pathogenesis and high mortality of A. baumannii including outer membrane proteins, lipopolysaccharide, capsule, phospholipase, nutrient- acquisition systems, efflux pumps, protein secretion systems, quarom sensing and biofilm production.

Characterization of Sequence Types and Mechanisms of Resistance to Tigecycline Among Acinetobacter baumannii Isolated from Children.

The present study aimed to investigate the mechanisms of resistance to tigecycline and to determine sequence types of Acinetobacter baumannii isolates recovered from children, using the Multilocus Sequence Typing (MLST). A total of 74 A. baumannii isolates were recovered from patients at one of the children's hospital in Tehran, Iran.

Surface layer protein A from hypervirulent Clostridioides difficile ribotype 001 can induce autophagy process in human intestinal epithelial cells.

Clostridioides difficile is the leading cause of nosocomial diarrhea with high morbidity and mortality worldwide. C. difficile strains produce a crystalline surface layer protein A (SlpA), which is an absolute necessity for its pathogenesis.

Decreased Susceptibility of Isolates to Azithromycin in Children in Tehran, Iran.

Azithromycin (AZT) has widely been used for the treatment of shigellosis in children. Recent studies showed a high rate of decreased susceptibility to azithromycin due to different mechanisms of resistance in isolates. Accordingly, the purpose of this study was to investigate the role of azithromycin resistance mechanisms of isolates in Iran during a two-year period.

Virulence genes expression profiling of different Shigella flexneri serotypes in response to sub-inhibitory concentrations of azithromycin and ciprofloxacin.

Background: Shigellosis is a self-limiting disease that antibiotic therapy could decrease its complications and duration. However, sublethal levels of antibiotics, may lead to alteration in disease state, besides its role in the emergence of resistant variants. To understand this link, we investigated diversity of Shigella serogroups in children with diarrhea, diversity of S.

Prevalence of β-lactamase-encoding genes and molecular typing of Acinetobacter baumannii isolates carrying carbapenemase OXA-24 in children.

Background: β-Lactam antibiotics have been broadly used for the treatment of Acinetobacter baumannii infections, resulting in development of β-lactam inactivating β-lactamases. Here, we described antibiotic resistance rate, prevalence of β-lactamase-encoding genes, and clonal relationships of A. baumannii strains isolated from children referred to Children's Medical Center in Tehran, Iran, during 2019-2020.

Genetic diversity and phylogenetic analysis of the surface layer protein A gene (slpA) among Clostridioides difficile clinical isolates from Tehran, Iran.

Clostridioides difficile is the most common causative agent of healthcare-associated diarrhea. C. difficile strains produce a crystalline surface layer protein (SlpA), encoded by the slpA gene.

Antibiotic resistance, biofilm formation, and biofilm-associated genes among Stenotrophomonas maltophilia clinical isolates.

Objective: The purpose of the present study was to investigate the antimicrobial susceptibility pattern, biofilm production, and the presence of biofilm genes among the S. maltophilia clinical isolates. A total of 85 clinical isolates of S.

Characteristics and diversity of mutations in regulatory genes of resistance-nodulation-cell division efflux pumps in association with drug-resistant clinical isolates of Acinetobacter baumannii.

Background: This study was aimed to characterize the genetic diversity and expression of three putative resistance-nodulation-cell division (RND)-type efflux systems and their contribution to multidrug efflux in clinical isolates of Acinetobacter baumannii.

Methods: Antimicrobial susceptibility testing of 95 A. baumannii isolates was determined by Kirby-Bauer disk diffusion for 18 antibiotics and minimum inhibitory concentration (MIC) of colistin was determined by the broth microdilution method.

Anti-proliferative effects of cell wall, cytoplasmic extract of and nisin through down-regulation of on SW480 colorectal cancer cell line.

Background And Objectives: Colorectal cancer is one of the most types of cancer. Researchers have shown that lactic acid bacteria have antitumor activity. The cell wall of , as the bacterial cytoplasmic extract and nisin can affect the proliferation of cancer cells.

Molecular characterization of pathogenicity locus (PaLoc) and tcdC genetic diversity among tcdABClostridioides difficile clinical isolates in Tehran, Iran.

Clostridioides difficile is the main cause of healthcare-associated diarrhea worldwide. It is proposed that certain C. difficile toxinotypes with distinct pathogenicity locus (PaLoc) variants are associated with disease severity and outcomes.

Genetic relatedness of the isolates in stool and urine samples of patients with community-acquired urinary tract infection.

Background: Community-acquired urinary tract infection (CA-UTI) could be caused by endogenous or exogenous routes. To show this relationship, we investigated molecular fingerprints and genotypes of paired isolated from the urine of symptomatic patients and their fecal samples.

Results: Out of the studied patients, 63 pairs of isolates were obtained simultaneously from their urine and feces samples.

In silico analysis of a chimeric fusion protein as a new vaccine candidate against type A and alpha toxins.

In silico analysis is the most important approach to understand protein structure and functions, and the most important problem for designing and producing a fusion construct is producing large amounts of functional protein. type A and produce alpha () and alpha toxins respectively. can cause gas gangrene and gastrointestinal diseases.

Characterization of biofilm formation and virulence factors of isolates from paediatric patients in Tehran, Iran.

Objectives: can cause several infections. Its capability to form biofilm has been reported to be a vital property involved in the bacteria's pathogenesis. Various genes contributing to biofilm formation have not yet been completely clarified.

Chronic Suppurative Otitis Media: A Case Report.

Background Context: Chronic Suppurative Otitis Media (CSOM) is a common cause of hearing impairment and disability. CSOM caused by Pseudomonas aeruginosa is usually treated with topical ciprofloxacin and resistance to ciprofloxacin in CSOM isolates has rarely been reported.

Case Presentation: A 24-year-old male patient with CSOM due to p.

High Rates of Antimicrobial Resistance and Virulence Gene Distribution Among spp. Isolated from Pediatric Patients in Tehran, Iran.

Background: continues to be important causes of acute pediatric diarrhea worldwide. produces numerous virulence factors involved in colonization and invasion into epithelial cells which eventually result in the disease. The present study was conducted to evaluate the prevalence of virulence genes and to investigate antibiotic resistance profiles among isolates obtained from pediatric patients in Iran.

Antimicrobial Resistance and Molecular Characteristics of Methicillin-resistant Isolates from Children Patients in Iran.

Introduction: Methicillin-resistant  (MRSA) causes high rates of mortality and a substantial burden to health systems worldwide. Here, we investigated the antimicrobial susceptibility and molecular characteristics of MRSA isolated from children referred to Children's Medical Center in Tehran.

Materials And Methods: A total of 98 MRSA isolates were collected from children.