1,721,039 research outputs found
Drug efflux transporters in Staphylococcus pseudintermedius: in silico prediction and characterization of resistance
No full textObjectives To perform an in silico prediction of drug efflux pumps (EPs) in Staphylococcus pseudintermedius and investigate their role in conferring resistance to antibiotic and biocidal agents and biofilm formation. Methods A S. pseudintermedius efflux mutant was obtained by stimulating an isogenic line (ATCC 49444) with increasing concentrations of an efflux system substrate. Changes in antimicrobial susceptibility and biofilm-forming capability were evaluated in the presence/absence of the EP inhibitors (EPIs) thioridazine and reserpine and the efflux activity was assayed by fluorometry. Homologues of EPs of Staphylococcus aureus and Staphylococcus epidermidis were searched by exploratory GenBank investigations. Gene expression analyses and sequencing were then conducted on selected genes. Results Susceptibility to chlorhexidine, gentamicin and ciprofloxacin, but not enrofloxacin, was affected by the increased efflux and it was variably restored by the EPIs. The efflux mutant showed much greater biofilm formation that the original strain, which was significantly inhibited by thioridazine and reserpine at MIC/2. A high expression of norA, which was mgrA-independent, was found in the S. pseudintermedius efflux mutant, apparently regulated by an 11 bp deletion in its promoter region, whilst lmrB was transitorily overexpressed. icaA, which encodes the polysaccharide intercellular adhesin forming the extracellular matrix of staphylococcal biofilm, was also up-regulated. Conclusions EPs, particularly NorA, are supposed to have complex involvement in multiple stages of resistance development. Overexpression of EPs appears to be correlated with a remarkable increase of S. pseudintermedius biofilm production; however, the regulatory mechanisms remain to be explored
Effetti di un trattamento omeopatico e di uno fitoterapico sulla proliferazione linfocitaria nel pollo
No full textAtrophy of the prymary lymphoid organs of meat pigeons in Italy associated with circovirus particles in the bursa of Fabricius
No full textDuring a survey effected in a meat pigeon slaughterhouse of central Italy, atrophy of primary lymphoid organs (bursa of Fabricius and thymus) and hypoplasia of bone marrow were observed. Histologic, ultrastructural, and hematologic examinations were performed on a total of 80 randomly selected 30-day-old meat pigeons. By histologic studies, lymphocytic depletion and necrosis with cyst formations in the bursa of Fabricius were detected in all subjects that showed thymus and bursa atrophy at necropsy. Basophilic intranuclear inclusions were also observed in bursal cells. After ultrastructural studies, these inclusions were proved to be viral particles resembling circoviruslike particles in morphology and size. Severe lymphocytic depletion of the bursa was plausibly associated with the presence of the viral particles
Trattamento delle salmonellosi in piccioni di allevamento mediante la tecnica dell’esclusione competitiva
No full textEditorial: Diagnostic procedures in veterinary microbiology and infectious diseases, volume II
No full textAmiloide sierica, fibrinogeno ed aptoglobina come marcatori precoci di complicazioni post-chirurgiche nel cavallo: risultati preliminari
No full textLa finalità di questa ricerca preliminare è stata quella di valutare l’utilizzo della
proteina amiloide sierica A (SAA), del fibrinogeno e dell’aptoglobina come marcatori di flogosi e
come strumenti ematochimici per il monitoraggio del decorso clinico di cavalli affetti da patologie
di diversa natura
- …
