RESUMO
@#In recent years, the etiology of periodontitis has tended to be based on the theory of flora imbalance. That is, periodontitis is not caused by specific bacteria but by the breakdown of the oral flora balance, which leads to an immune imbalance. Imbalanced bacterial flora cooperate with each other to produce virulent factors that destroy organism tissues and induce immune cells to produce abnormal levels of cytokines, causing greater damage. This article reviews the initiation of a flora imbalance, the interaction between bacteria, the immune damage of the host and the prevention and treatment of the flora imbalance. The literature review shows that peroxidase released by inflammatory reactions, host immune responses to pathogenic microorganisms and some systemic factors, such as diabetes, can trigger flora imbalance. As a result, ion transport, substance synthesis and metabolism of bacteria change; virulence factors increase; and the oral flora balance is disrupted. Red complex bacteria enter gingival epithelial cells, produce adhesin, and selectively inhibit the expression of specific chemokines, which is beneficial for other pathogenic bacteria to enter gingival epithelial cells. Toxicity factors increase throughout the body, directly destroying body tissues and inducing innate and adaptive immune responses, thus causing related immune damage. The dysbacteriosis model of periodontitis provides a new idea for the prevention and treatment of periodontitis, such as using biological factors, bacteriophages, probiotics and other methods to reduce the number of periodontal pathogens to restore the steady state of periodontal flora.
RESUMO
Vibrio alginolyticus está asociado a enfermedades en acuicultura. El uso indiscriminado de antibióticos ha conllevado a la búsqueda de alternativas en el tratamiento de enfermedades bacterianas, entre ellas la aplicación de bacteriófagos, los cuales infectan y destruyen selectivamente bacterias. En ese sentido, en este trabajo se aisló un bacteriófago altamente lítico a V. alginolyticus el cual fue denominado Va1, con el objetivo de evaluar los parámetros físicos químicos en los cuales es viable. Para esto, se evaluó al bacteriófago Va1 en diferentes condiciones de pH, temperatura, cloroformo. El fago Va1 presenta mayores títulos a 20 y 30 °C y pH de 5 a 8 disminuyendo su viabilidad a partir de 40 °C y en unidades de pH menores de 5. La exposición al cloroformo redujo la viabilidad del fago Va1 en un 25%. A partir de la curva de un paso se determinó que el periodo de latencia y el tamaño de la explosión fueron de 20 minutos y 192 UFP/centro infectivo respectivamente. Al microscopio electrónico de transmisión el fago Va1 evidencio una cabeza icosaedrica y una cola no contráctil, características propias de la familia Podoviridae. En conclusión, el fago Va1 presenta características potenciales para su uso en fagoterapia
Vibrio alginolyticus is associated with diseases in aquaculture. The misuse of antibiotics has led to the search for alternatives in the treatment of bacterial diseases, among them the application of bacteriophages that infect and destroy bacteria selectively. In this way, a highly lytic V. alginolyticus bacteriophage, termed Va1, was isolated, with the aim to evaluate its physical chemical parameters. For this purpose, different temperature, pH, chloroform exposure and host range conditions were evaluated. The temperature stability of phage Va1 showed higher titers at 20 and 30 °C decreasing from 40 °C. With respect to pH, the highest titers for the bacteriophage were between 5 and 8, and chloroform exposure reduced viability of the Va1 phage by 25%. The one-step curve determined that the latency period and the burst size were 20 minutes and 192 PFU / infective center respectively. Under the transmission electron microscope, the Va1 phage showed an icosahedral head and a non-contractile tail, belonging to the Podoviridae family. In conclusion, Va1 phage presents potential characteristics for use in phage therapy