Biogenic silver nanoparticles in the treatment of experimental pythiosis Bio-AgNP in pythiosis therapy.

Pythiosis is a rapidly progressing disease that can be lethal to affected individuals due to resistance to available therapeutic protocols. The disease affects mammals, with the largest number of reports in horses and humans. The present study investigated the activity of biogenic silver nanoparticles (bioAgNP) in the treatment of experimental pythiosis. The disease was reproduced in nine female 90-day-old New Zealand rabbits. Animals were divided into three groups: group1 (control, n = 3) daily and topically treated with a nonionized gel-based formulation and 1 ml of sterile distilled water intralesion administered every 48 hours; group 2 (n = 3), daily and topically treated with gel-based formulation containing 1 µg/ml bio-AgNP; group 3 (n = 3), treated with 1 ml bio-AgNP in 1 µg/ml aqueous solution intralesion administered every 48 hours. Animals were treated for 45 days, and the area of subcutaneous lesions was measured every 5 days. Results showed that groups 2 and 3 differed from control group (P < .05) in the lesion area, as well as the amount of hyphae within the lesions. It was observed that lesions of treated animals (groups 2 and 3) did not differ from each other, showing that the application route did not influence the regression of lesions. However, it was observed that one animal from group 2 reached clinical cure at 35 days of treatment. This research is pioneer in the application of nanocomposites for the treatment of experimental pythiosis and showed that bio-AgNP can be powerful allies of integrative medicine and can be included in pythiosis therapeutic protocols.

Chronic cardiomyopathy and encephalic spongy changes in sheep experimentally fed Ateleia glazioviana / Miocardiopatia crônica e degeneração esponjosa do encéfalo em ovinos intoxicados experimentalmente por Ateleia glazioviana

Fifteen mature crossbred sheep were fed different daily amounts (2.5-35g kg-1 bw) of the fresh green leaves of Ateleia glazioviana for different periods of time (1-24 days). One sheep was not fed the plant and served as a control. All 16 sheep were euthanatized at different stages of the experiment, necropsied, and several organs, including heart and brain were evaluated histologically. Samples of five brain regions from three affected sheep were evaluated by electron microscopy. Clinical signs observed in three sheep included depression, anorexia, general weakness, staggering gait and prolonged recumbency. One sheep had signs of congestive heart failure. Necropsy findings included subcutaneous dependent edema and edema of the body cavities in two sheep and nutmeg liver in one. Histopathological findings included degeneration, necrosis and interstitial fibrosis in the myocardium of four sheep and vacuolation of cerebral white matter (spongy degeneration, status spongiosus) in 10 sheep, although this latter change were marked only in two of those 10. The ultrastructure of the brain lesion was morphologically consistent with that found in diseases grouped as spongiform myelinopathies in which vacuolation of the myelin occurs in the absence of significant myelin breakdown or phagocytosis. The morphology and pathogenesis of the chronic cardiomyopathy and of the cerebral spongy degeneration in affected sheep in this experiment are discussed and compared with other similar conditions in domestic ruminants.

Quinze ovinos mestiços adultos receberam quantidades variáveis (2,5-35g kg-1 pv), por via oral, das folhas verdes frescas de Ateleia glazioviana durante períodos de tempo que variaram de 1 a 24 dias. Um ovino não recebeu a planta e serviu como controle. Todos os 16 ovinos foram submetidos à eutanásia em diferentes estágios do experimento, necropsiados, e vários órgãos, incluindo coração e encéfalo, foram avaliados histologicamente. Fragmentos de cinco regiões do encéfalo de três ovinos afetados foram avaliados por microscopia eletrônica. Sinais clínicos observados em três ovinos incluíam depressão, anorexia, fraqueza geral, andar vacilante e decúbito prolongado. Um ovino apresentou sinais de insuficiência cardíaca congestiva. Achados de necropsia incluíram edema subcutâneo de declive e das cavidades orgânicas em dois ovinos e fígado de noz-moscada em umdeles. Achados histopatológicos incluíram necrose e fibrose intersticial no miocárdio de quatro ovinos e vacuolização da substância branca (degeneração esponjosa, status spongiosus) em 10 ovinos, embora essa última alteração fosse acentuada em apenas dois ovinos. A ultra-estrutura das lesões encefálicas foi morfologicamente consistente com o que é descrito em um grupo de doenças conhecidas como mielinopatias espongiformes nas quais a vacuolização da mielina ocorre na ausência de degradação significativa da mielina ou fagocitose. A morfologia e patogênese da miocardiopatia crônica e da degeneração esponjosa encefálica nos ovinos deste experimento são discutidas e comparadas com outras condições semelhantes em animais domésticos.