Search

The review aimed to investigate the diversity of oral microbiota and its influencing factors, as well as the association of oral microbiota with oral health and the possible effects of dysbiosis and oral disorder. The oral cavity harbors a substantial microbial burden, which is particularly notable compared to other organs within the human body. In usual situations, the microbiota exists in a state of equilibrium; however, when this balance is disturbed, a multitude of complications arise. Dental caries, a prevalent issue in the oral cavity, is primarily caused by the colonization and activity of bacteria, particularly streptococci. Furthermore, this environment also houses other pathogenic bacteria that are associated with the onset of gingival, periapical, and periodontal diseases, as well as oral cancer. Various strategies have been employed to prevent, control, and treat these disorders. Recently, techniques utilizing microbiota, like probiotics, microbiota transplantation, and the replacement of oral pathogens, have caught the eye. This extensive examination seeks to offer a general view of the oral microbiota and their metabolites concerning oral health and disease, and also the resilience of the microbiota, and the techniques used for the prevention, control, and treatment of disorders in this specific area. [ABSTRACT FROM AUTHOR]

Background: The use of probiotics is emerging as an innovative approach to managing oral health issues and mediating the immune system. The current study assessed the in vitro impacts of non-orally isolated probiotics on periodontitis and tooth decay pathogens. Methods: Briefly, the persistence of probiotics in exposure to oral cavity enzymes, hydrogen peroxide, and saliva samples was examined. It was also investigated the biofilm formation and aggregation ability of probiotics, the adherence of probiotics in human gingival fibroblast cell (HGFC) lines and molar teeth samples, and the potential of probiotics to co-aggregate with oral pathogens. Additionally, the current study evaluated the effects of live probiotics on virulence gene expression, biofilm production of main oral pathogens, and changes in inflammation markers. Results: The probiotics remained alive when exposed to enzymes in the oral cavity, hydrogen peroxide, and saliva at baseline, 1, 3, and 5 h after incubation at 37°C (p-value <0.05). Probiotics demonstrated to produce biofilm and aggregation, as well as adherence to HGFCs and maxillary molars (p-value >0.05). They showed significant co-aggregation with oral pathogens, which were recorded as 65.57% for B. bifidum 1001 with S. mutans, 50.06% for B. bifidum 1005 with P. gingivalis, 35.6% for L. plantarum 156 with F. nucleatum, and 18.7% for B. longum 1044 with A. actinomycetemcomitans after 8 h of incubation. A balance between pro-inflammatory and anti-inflammatory cytokines, along with inhibition of biofilm formation and changes in virulence gene transcripts, were observed. However, most of these changes were not statistically significant (p-value >0.05). Conclusion: This study demonstrated the direct link between adhesiveness, aggregation, and biofilm formation with probiotic antibacterial activity. In addition to the careful selection of suitable probiotic strains, the concentration and origin of probiotic isolates should be considered. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus aureus is one of the most important food-borne pathogens. The objective of this study was to determine the prevalence, molecular types and drug resistance pattern of S. aureus isolated from retail meat in Tabriz city. Materials & Methods: 60 raw meat samples (chicken and beef) were taken from different markets and were inoculated in selective Mueller Hinton broth media supplemented with 10% NaCl. Identification of S. aureus isolates was performed using conventional biochemical tests. Susceptibility to different antibiotics and genotypes of isolates were determined by disc diffusion and spa typing methods respectively. Results: Fifteen S. aureus strains were isolated from 60 different meat samples which belonged to spa types t14870, t3802, t1814, t491, t386, t3424 and spa type t14870 with the frequency of 33.3% was the most prevalent genotype among S. aureus isolates. spa types of three isolates were not found in Ridom Spa Server data base and were considered as novel types. About 46.6% of isolates were resistant to more than one antibiotic and 13.3% of isolates were identified as methicillin resistant S. aureus (MRSA). Tigecycline, imipenem and ceftaroline were found to be the most effective agents against S. aureus isolates. Conclusion: Oure results revealed a 25% contamination rate with S. aureus. Most of the molecular types of isolates were found to be linked to human infections. High rate of antibiotic resistance was observed among the isolates which poses a great threat to public health. [ABSTRACT FROM AUTHOR]