Infectious Diseases
Lyle D. Broemeling in Bayesian Analysis of Infectious Diseases, 2021
Certain antibiotics such as penicillin, streptomycin, and tetracycline are very effective against bacterial infections. The designation “antibiotic” is based on the concept of antibiosis, or the use of substances made by one living thing to kill another. Antibiotics are made by bacteria and molds that are specially cultured by commercial drug laboratories. Antibiotics kill bacteria and other disease organisms in a variety of ways. For example, some destroy cell walls, while others interfere with the multiplication of bacteria or fatally alter the way the bacteria manufacture vital proteins. Still others mix up the genetic plan of the bacteria. Ordinarily, an antibiotic tricks bacteria into using the antibiotic’s chemicals instead of closely related ones that organisms really need for making the key enzymes required for their growth and reproduction. With the antibiotic assimilated into their systems, instead of vital chemicals, an essential activity or structure of the pathogens is lacking and they die.
Chronic Prostatitis/Chronic Pelvic Pain Syndrome—A Urologist’s Perspective
Gary W. Jay in Practical Guide to Chronic Pain Syndromes, 2016
CP/CPPS should, by definition, exclude men with a proven bacteriologic etiology. Therefore, antibiotics are theoretically inappropriate for the treatment of this condition. Nevertheless, most practitioners are inclined to initiate at least one trial of long-term antibiosis. Evidence-based research finds limited validation for the use of antibacterials, even in the face of chronic bacterial prostatitis, let alone for abacterial CP/CPPS. Cure rates, based on sterilization of the prostatitic secretions, even for this more specific indication, ranged from 0% to 90% and correlated poorly with symptomatic responses. Limited evidence from retrospective studies suggests that quinolones [e.g., ciprofloxacin (Cipro), levofloxacin (Levaquin)1 may be more effective than trimethoprim-sulfamethoxazole (Bactrim, Septra). Absent a well-documented bacterial culture, this recommendation must be weighed against the significant cost differential between these two options (1).
The Journey through the Gene: a Focus on Plant Anti-pathogenic Agents Mining in the Omics Era
Mahendra Rai, Chistiane M. Feitosa in Eco-Friendly Biobased Products Used in Microbial Diseases, 2022
In turn, antifungal activities are widely reported (Barile et al. 2007; Porsche et al. 2017), and the antibiosis mechanism is clarified. The primary mode of saponin antifungal action involves pore formation and loss of membrane integrity, which cause fungal cell death. The deleterious effect is associated with a complex formation between saponin and ergosterol, the major fungal membrane sterol (Weete 1989; Bonanomi et al. 2009). As ergosterol is not present in plants, these complexes do not form, so phytotoxicity is avoided in plant cells.
Stenotrophomonas maltophilia biofilm: its role in infectious diseases
Published in Expert Review of Anti-infective Therapy, 2019
Samantha Flores-Treviño, Paola Bocanegra-Ibarias, Adrián Camacho-Ortiz, Rayo Morfín-Otero, Humberto Antonio Salazar-Sesatty, Elvira Garza-González
In a search for a research model that mimicked biofilm found in the respiratory tract of immunocompromised patients (e.g. multispecies biofilm), a mixed biofilm of S. maltophilia and Aspergillus fumigatus fungus was assessed [85]. Scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy were used to visualize biofilm structures such as an extracellular matrix embedded with fungal hyphae and bacteria. Additionally, S. maltophilia had an antibiosis effect on A. fumigatus, marked by decreased fungus growth and thickened fungal cell walls. This antibiosis effect was also strain dependent: S. maltophilia clinical strains isolated from humans produced higher fungal growth inhibition and hyphal phenotype modification in the mixed biofilm than those isolated from animals or the environment [86]. On yeast Candida albicans, S. maltophilia causes interference of yeast-to-hyphal transition and biofilm formation via DSF synthesis [87]. These studies suggest that S. maltophilia behaves differently in multispecies biofilm, depending on the type of species present. S. maltophilia exerts a negative influence on fungus and yeast biofilm production, but in contact with other bacteria, such as P. aeruginosa, biofilm formation is promoted.
Reliability of antioxidant potential and in vivo compatibility with extremophilic actinobacterial-mediated magnesium oxide nanoparticle synthesis
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Kavitha Kandiah, Thenmozhi Jeevanantham, Balagurunathan Ramasamy
Salem magnesite reserves are unique for their cryptocrystalline structure, which is best suited for manufacturing refractory bricks. Magnesite of the Salem region is relatively low in calcium oxide and high in silica content [12]. The mineral composition of magnesite mine contains magnesite-rich ultra-basic and low concentration of silicon oxide (SiO2), 2.38%; aluminium oxide (Al2O3), 0.10%; ferric oxide (Fe2O3), 0.08%; ferrous oxide (FeO), 0.06%;calcium oxide (CaO), 0.42%; and MgO, 46.35%. Magnesite deposits cover an area of ∼5000 km; the pH of the soil is alkaline; and the temperature is high and dry in plains. In addition, the microorganism existing in the magnesite soil has special abilities to survive in the extremophilic environment. Among them, actinobacteria reside in a unique state due to their high G + C content and their ability to produce a variety of bioactive secondary metabolites [12–14]. The extremophilic actinobacteria show several adaptive strategies such as antibiosis, switching between different metabolic modes (i.e. autotrophy, heterotrophy and saprobes), and production of specific enzymes to survive under unfavourable environmental conditions. Actinobacteria are an ecologically important group and widely found in terrestrial and aquatic ecosystems that play an important role in several biological processes such as biogeochemical cycles, bioremediation [14,15], bioweathering and plant growth promotion [16]. Many researchers have synthesized silver and gold NPs using actinobacteria [14–17].
Ureteral stent-associated infection and sepsis: pathogenesis and prevention: a review
Published in Biofouling, 2019
Kymora B. Scotland, Joey Lo, Thomas Grgic, Dirk Lange
Indwelling ureteral stents have been associated with the development of UTIs. This is thought to be secondary to the formation of microbial biofilm on the stent surface. Bacteria in biofilm are able to avoid antimicrobial activity via a number of mechanisms and phenotypic changes. Further investigations of these mechanisms will aid in identifying therapeutic targets in the treatment of urinary tract infections and urosepsis. While several strategies have been employed for ureteral stent coatings, there has been little historical success. Newer efforts are now focused on the use of nanotechnology, particularly the use of nanoparticle impregnation of medical devices, in an attempt to devise implants with antimicrobial properties while having minimal toxicity for patients. This field holds promise for the development of improved ureteral stents. Current management of ureteral stents includes practical strategies for decreasing stent-associated infection and urosepsis such as frequent replacement and early removal. Treatment of these infections continues to depend largely on the use of antibiotics. The choice of culture specific, effective antibiosis must be carefully considered with respect to both the rising public health costs of urosepsis and the seriousness of this infection.
Related Knowledge Centers
- Antibiotic
- Bacteria
- Biotechnology
- Pathogen
- Biological Interaction