RESUMO
Staphylococcus aureus is one of the most common infectious agents, causing morbidity and mortality worldwide. Most pathogenic bacteria are classified in the group of mesophilic bacteria and the optimal growth temperature of these bacteria changes between 33 and 41 °C. Increased temperature can inhibit bacterial growth and mobility, which in turn, can trigger autolysis and cause cell wall damage. Hyperthermia treatment is defined as a heat-mediated treatment method applied using temperatures higher than body temperature. Nowadays, this treatment method is used especially in the treatment of tumours. Hyperthermia treatment is divided into two groups: mild hyperthermia and ablative or high-temperature hyperthermia. Mild hyperthermia is a therapeutic technique in which tumour tissue is heated above body temperature to produce a physiological or biological effect but is often not aimed at directly causing significant cell death. The goal of this method is to achieve temperatures of 40-45 °C in human tissues for up to 2 h. Hyperthermia can be used in the treatment of infections caused by such bacterial pathogens. In addition, using hyperthermia in combination with antimicrobial drugs may result in synergistic effects and reduce resistance issues. In our study, we used two different temperature levels (37 °C and 45 °C). We assessed growth inhibition, some virulence factors, alteration colony morphologies, and antimicrobial susceptibility for several antibiotics with three methods (Kirby-Bauer, E-test and broth microdilution) under hyperthermia. In the study, we observed that hyperthermia affected the urease enzyme, antibiotic sensitivity levels showed synergy with hyperthermia, and changes occurred in colony diameters and affected bacterial growth. We hypothesise that hyperthermia might be a new therapeutic option for infectious diseases as a sole agent or in combination with different antimicrobials.
Assuntos
Hipertermia Induzida , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Hipertermia Induzida/métodos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Temperatura Alta , Infecções Estafilocócicas/terapiaRESUMO
The purpose of this paper is to reflect on the experiences of safety and security management students, enrolled in an undergraduate course in the Netherlands, and present quantitative data from an online survey that aimed to explore the factors that have contributed to students' satisfaction with, and engagement in, online classes during the COVID-19 pandemic. The main findings suggest an interesting paradox of technology, which is worth further exploration in future research. Firstly, students with self perceived higher technological skill levels tend to reject online education more often as they see substantial shortcomings of classes in the way they are administered as compared to the vast available opportunities for real innovation. Secondly, as opposed to democratising education and allowing for custom-made, individualistic education schedules that help less-privileged students, online education can also lead to the displacement of education by income-generating activities altogether. Lastly, as much as technology allowed universities during the COVID-19 pandemic to continue with education, the transition to the environment, which is defined by highly interactive and engaging potential, may in fact be a net contributor to the feelings of social isolation, digital educational inequality and tension around commercialisation in higher education.
RESUMO
Hyperthermia is a therapeutic technique in which body tissue is exposed to temperatures in the region of 40-45⯰C to induce a physiological or biological effect. Swarming motility is an important virulence factor for Proteus mirabilis and Pseudomonas aeruginosa and swarming phenomenon is a coordinated multicellular movement of differentiated bacterial population over semi-solid surfaces. In this study, we aimed to investigate the inhibitory effect of hyperthermia on bacterial swarming motility using a modified thermobiogram method and show the potential of this thermal method to treat bacterial infections. Ten P. mirabilis and 10 P. aeruginosa clinical isolates were included in the study. Sheep blood agar (SBA) plates were prepared and inoculated with bacterial suspensions of clinical isolates. Inoculated SBA plates were incubated inside 2 different incubators; at 37⯰C and 45⯰C for 20â¯h. The diameter of bacterial growing zones (swarming diameters) were measured every 2â¯h and noted. Finally, Gram stains of the isolates were prepared for microscopic examination. Wilcoxon signed-rank test was used to compare the swarming inhibition rates of the isolates incubated at 37⯰C and 45⯰C. Regarding P. mirabilis species, a significant difference was found between two different temperatures (Pâ¯=â¯0.0078). So, a temperature at the level of hyperthermia significantly inhibited the swarming motility of P. mirabilis isolates. In addition, transformation to coccus form was observed at 45⯰C. We speculate that these findings might be useful for employing thermal therapies including hyperthermia method to treat infectious diseases caused by swarming bacterial pathogens in the future.