Plants and Small Molecules: An Up-and-Coming Synergy.

The emergence of Arabidopsis thaliana as a model system has led to a rapid and wide improvement in molecular genetics techniques for studying gene function and regulation. However, there are still several drawbacks that cannot be easily solved with molecular genetic approaches, such as the study of unfriendly species, which are of increasing agronomic interest but are not easily transformed, thus are not prone to many molecular techniques. Chemical genetics represents a methodology able to fill this gap. Chemical genetics lies between chemistry and biology and relies on small molecules to phenocopy genetic mutations addressing specific targets. Advances in recent decades have greatly improved both target specificity and activity, expanding the application of this approach to any biological process. As for classical genetics, chemical genetics also proceeds with a forward or reverse approach depending on the nature of the study. In this review, we addressed this topic in the study of plant photomorphogenesis, stress responses and epigenetic processes. We have dealt with some cases of repurposing compounds whose activity has been previously proven in human cells and, conversely, studies where plants have been a tool for the characterization of small molecules. In addition, we delved into the chemical synthesis and improvement of some of the compounds described.

Pseudomonas exit site infections in continuous ambulatory peritoneal dialysis patients.

The purpose of this study is to examine the natural history of Pseudomonas aeruginosa exit site infections in continuous ambulatory peritoneal dialysis (CAPD) patients treated with oral ciprofloxacin and local exit site care. A retrospective view was undertaken of 18 episodes of P. aeruginosa exit site infections developing in 17 patients maintained on CAPD during 1989 and 1990. Standardized therapy for the exit site infection consisted of oral ciprofloxacin (500 mg twice daily) and local exit site care with antiseptic agents. Fifteen (83%) of 18 of the pseudomonas exit site infections resolved with therapy. Three episodes (17%) required catheter removal to successfully eradicate the infection. Four of the 15 patients whose exit site infections resolved developed P. aeruginosa peritonitis 2 to 9 months after the clinical resolution of the exit site infection. The majority of pseudomonas exit site infections in CAPD patients can be successfully treated with oral ciprofloxacin and local care. Approximately 17% of the patients in this study required catheter removal to successfully eradicate the infection and an additional 22% of the patients developed pseudomonas peritonitis several months after the resolution of the exit site infection.