RESUMO
An eleven-year-old Pit Bull Terrier was presented to the veterinary practice with an acute onset of whole-body seizures. The clinical signs developed in a garden where the dog was kept that morning. There was a suspicion of tremorgenic mycotoxin poisoning by compost as the dog had vomited parts of compost right before the onset of the seizures and there was a pile of compost located in the garden. The dog underwent immediate decontamination following supportive treatment and recovered fully within 24 h of intensive care. The samples of the vomit and parts of the compost were cultivated. In the sample of the vomit, Penicillium sp. was found. Subsequently, tremorgenic mycotoxins paxilline, penitrem A and roquefortine C were determined chromatographically at significant concentrations in the vomit and a growth medium with cultivated Penicillium sp. The aim of this work is to describe the complex therapeutic and diagnostic approach to the patient with a suspected tremorgenic mycotoxin poisoning where a combination of mycological and chromatographic analyses was used to confirm the diagnosis. To the best of our knowledge, this is the first confirmed case of canine tremorgenic mycotoxicosis in the Czech Republic and the first reported case of paxilline poisoning in a dog.
RESUMO
We studied the early stages of pellicle formation by Mycobacterium smegmatis on the surface of a liquid medium [air-liquid interface (A-L)]. Using optical and scanning electron microscopy, we showed the formation of a compact biofilm pellicle from micro-colonies over a period of 8-30 h. The cells in the pellicle changed size and cell division pattern during this period. Based on our findings, we created a model of M. smegmatis A-L early pellicle formation showing the coordinate growth of cells in the micro-colonies and in the homogeneous film between them, where the accessibility to oxygen and nutrients is different. A proteomic approach utilizing high-resolution two-dimensional gel electrophoresis, in combination with mass spectrometry-based protein identification, was used to analyse the protein expression profiles of the different morphological stages of the pellicle. The proteins identified formed four expression groups; the most interesting of these groups contained the proteins with highest expression in the biofilm development phase, when the floating micro-colonies containing long and more robust cells associate into flocs and start to form a compact pellicle. The majority of these proteins, including GroEL1, are involved in cell wall synthesis or modification, mostly through the involvement of mycolic acid biosynthesis, and their expression maxima correlated with the changes in cell size and the rigidity of the bacterial cell wall observed by scanning electron microscopy.
