Detection of bacterial contamination and DNA quantification in stored blood units in 2 veterinary hospital blood banks

Blood transfusions in veterinary medicine have become increasingly more common and are now an integral part of lifesaving and advanced treatment in small and large animals. Important risks associated with transfusion of blood products include the transmission of various infectious diseases. Several guidelines suggest what infectious agents to screen for in canine and feline transfusion medicine. However, while the risk of bacterial contamination of blood products during storage and administration has not been documented in veterinary medicine, it has emerged as a cause of morbidity and mortality in human transfusion medicine. Clinical experience shows that the majority of blood component bacterial contaminations are caused by only a few species. Unlike other types of bacteria, psychrotolerant species like Pseudomonas spp. and Serratia spp. can proliferate during the storage of blood units at 4°C from a very low titer at the time of blood collection to a clinically significant level (> 10⁵ CFU/mL) causing clinical sepsis resulting from red blood cell concentrate transfusions in human medicine. The purpose of this report was to describe the detection and quantification procedures applied in 4 cases of bacterial contamination of canine and feline blood units, which suggest the need for further investigations to optimize patients’ safety in veterinary transfusion medicine.     

Functional properties of purified vicilins from cowpea (Vigna unguiculata) and pea (Pisum sativum) and cowpea protein isolate

The major storage globulins (vicilins) of cowpea (Vigna unguiculata) and pea (Pisum sativum) seeds were purified by ammonium sulfate precipitation, and a semipurified cowpea protein isolate (CPI) was prepared by isoelectric precipitation. Some of the functional properties of these proteins, including solubility, foaming, and emulsifying capacities, were investigated and compared. The solubility of purified cowpea vicilin was reduced at pH 5.0, increasing markedly below and above this value. Pea vicilin exhibited poor solubility between pH 5.0 and pH 6.0, and CPI was little soluble in the pH range from 4.0 to 6.0. At neutral pH, the emulsifying activity indexes (EAI) of purified pea vicilin and CPI were 194 and 291 m(2)/g, respectively, which compare quite favorably to EAIs of 110 and 133 m(2)/g for casein and albumin, respectively. Remarkably, purified cowpea vicilin exhibited an EAI of 490 m(2)/g, indicating a very high emulsifying activity. Purified cowpea and pea vicilins exhibited lower foaming capacities and foam stablity indexes (FSI) than CPI. FSI values of 80 and 260 min were obtained for purified pea and cowpea vicilin, respectively, whereas a FSI value of 380 min was obtained for CPI. These results are discussed in terms of the possible utilization of purified vicilins or protein isolates from pea and cowpea in the food processing industry.     

A relevant long-term impact of the circulation of a potentially contaminated vaccine on the distribution of scrapie in Italy. Results from a retrospective cohort study

ABSTRACT: A sudden increase in the incidence of scrapie in Italy in 1997 was subsequently linked to theuse of a potentially infected vaccine against contagious agalactia. The relative risk for theexposed farms ranged between 6 and 40. The aim of this study was to assess the long-termimpact of exposure to the potentially scrapie-contaminated vaccine on the Italian classicalscrapie epidemic. We carried out a retrospective cohort study, fitting mixed-effects Poissonregression models, dividing national geographic areas into exposure categories on the basis ofthe vaccine circulation levels. We took into account the sensitivity of the surveillance systemapplied in the different areas. The population attributable fraction (PAF) was used to assessthe impact on the total population of farms associated with the effect of circulation of thevaccine. The provinces where the vaccine was more often sold were noted to have a higherlevel of disease when compared to those provinces where the vaccine was sold less often(incidence rate ratio [IRR]: 2.7; 95% confidence interval [CI]: 1.1-6.5). The populationattributable fraction was high (68.4%). Standardization techniques allowed to account for thepotential of geographical variability in the sensitivity of the Italian surveillance system.Although the number of the directly exposed farms was limited, an important long-termimpact of the vaccine circulation could be quantified in terms of secondary outbreaks likelydue to the exchange of animals from directly exposed flocks.