Fully Characterized Effective Bacteriophages Specific against Antibiotic-Resistant Enterococcus faecalis, the Causative Agent of Dental Abscess.

Background and Objectives: Enterococcus faecalis (E. faecalis) is a primary pathogen responsible for dental abscesses, which cause inflammation and pain when trapped between the crown and soft tissues of an erupted tooth. Therefore, this study aims to use specific phages as an alternative method instead of classical treatments based on antibiotics to destroy multidrug-resistant E. faecalis bacteria for treating dental issues. Materials and Methods: In the current study, twenty-five bacterial isolates were obtained from infected dental specimens; only five had the ability to grow on bile esculin agar, and among these five, only two were described to be extensive multidrug-resistant isolates. Results: Two bacterial isolates, Enterococcus faecalis A.R.A.01 [ON797462.1] and Enterococcus faecalis A.R.A.02, were identified biochemically and through 16S rDNA, which were used as hosts for isolating specific phages. Two isolated phages were characterized through TEM imaging, which indicated that E. faecalis_phage-01 had a long and flexible tail, belonging to the family Siphoviridae, while E. faecalis_phage-02 had a contractile tail, belonging to the family Myoviridae. Genetically, two phages were identified through the PCR amplification and sequencing of the RNA ligase of Enterococcus phage vB_EfaS_HEf13, through which our phages shared 97.2% similarity with Enterococcus phage vB-EfaS-HEf13 based on BLAST analysis. Furthermore, through in silico analysis and annotations of the two phages' genomes, it was determined that a total of 69 open reading frames (ORFs) were found to be involved in various functions related to integration excision, replication recombination, repair, stability, and defense. In phage optimization, the two isolated phages exhibited a high specific host range with Enterococcus faecalis among six different bacterial hosts, where E. faecalis_phage-01 had a latent period of 30 min with 115.76 PFU/mL, while E. faecalis_phage-02 had a latent period of 25 min with 80.6 PFU/mL. They were also characterized with stability at wide ranges of pH (4-11) and temperature (10-60 °C), with a low cytotoxic effect on the oral epithelial cell line at different concentrations (1000-31.25 PFU/mL). Conclusions: The findings highlight the promise of phage therapy in dental medicine, offering a novel approach to combating antibiotic resistance and enhancing patient outcomes. Further research and clinical trials will be essential to fully understand the therapeutic potential and safety profile of these bacteriophages in human populations.

Presence of HPV, EBV and HMTV Viruses Among Egyptian Breast Cancer Women: Molecular Detection and Clinical Relevance.

BACKGROUND: Oncogenic viruses, their possible association with breast cancer (BC) and effect on its clinical course are interesting issue. The present study evaluates the presence of human papillomavirus (HPV), EpsteinBarr virus (EBV), and human mammary tumor virus (HMTV) in BC and their relation with clinico-pathological characteristics. PATIENTS AND METHODS: This study was conducted on 80 Egyptian women with BC and 30 control women without known oncological disease. Forty formalin-fixed paraffin-embedded (FFPE) tissues, forty fresh tissue samples, and white blood cells (WBCs) of BC patients and WBCs of controls were subjected to a qualitative polymerase chain reaction (PCR). Quantitative real-time PCR was used to measure viral loads in fresh tissues of BC. The result was correlated with clinico-pathological characteristics of BC. RESULTS: HPV was detected in 33 (41.25%), EBV in 30 (37.5%) and HMTV in 33 (41.25%) BC patients. None of the control women was positive for HPV or EBV while HMTV was detected in 7 (23.3%). Among 40 BC WBCs specimens, HPV/HMTV were found together in 25%, followed by EBV/HMTV in 2.5% and EBV/HPV in 2.5%. However, the three viruses (HPV/EBV/HMTV) were found together in only 5%. In the 40 fresh BC tissues, the three viruses were found together in 12 (30%), EBV/HMTV in 7 (17.5%), HPV/HMTV in 4 (10%), and HPV/EBV in 4 (10%). EBV, HMTV, or multiple viral infections were associated with younger age of BC women. HPV, EBV, and HMTV median loads in fresh tissues were 4.8×103 copies/µL, 6.3×103 copies/µL, and 97 copies/µL, respectively. CONCLUSION: WBCs could be a more suitable specimen instead of fresh tissue for HMTV detection in BC patients to avoid invasive procedures. The presence of HPV, EBV, and HMTV together in Egyptian women with BC was significantly associated with younger age.

Epstein-Barr virus and cytomegalovirus infections and their clinical relevance in Egyptian leukemic pediatric patients.

BACKGROUND: Epstein-Barr virus (EBV) and human cytomegalovirus (CMV) infections are environmental risk factors affecting the outcome of cancer due to an impairment in the cell-mediated immunity. Therefore, this study aimed to detect the frequency of EBV and CMV DNA and their association with clinical characteristics and outcome of pediatric leukemic patients. METHODS: Samples of 50 immunocompromised pediatric leukemic patients and 30 apparently healthy children were subjected to the amplification of EBV DNA by one version of PCR targeting the Bam H1 W region of the genomic region of EBV, and the amplification of CMV DNA by targeting the CMV UL97 genomic region by a second round PCR. All investigations were performed on WBCs and sera. Results were correlated with the clinical and laboratory characteristics of the disease, and with overall survival. RESULTS: EBV and CMV DNA were detected in 20 and 54% of leukemic patients, respectively. Nine out of ten patients with EBV DNA (90%) were positive for CMV DNA in their sera. The presence of EBV DNA or CMV DNA was associated with neutropenia and a low total leukocyte count (TLC) (p = 0.02, 0.03, respectively). The presence of severe CMV disease, longer duration of febrile neutropenia, neutropenia, lymphopenia, thrombocytopenia and the presence of EBV DNA in patients' sera were significantly associated with worse overall survival. CONCLUSION: The detection of CMV disease and EBV DNA is relatively common in leukemic children and is significantly associated with a decline in the overall survival.