Resumo A carga parasitária de Leishmania infantum chagasi do fígado foi comparada às anormalidades hemostáticas, bem como aos achados clínicos, laboratoriais e histopatológicos em cães com leishmaniose visceral. A carga parasitária do fígado de 30 cães naturalmente infectados por L. infantum chagasi foi avaliada por PCR quantitativo em tempo real e os resultados foram comparados com bioquímica sérica e achados de hemostasia primária e secundária. Além disso, foram descritas as lesões hepáticas nestes cães. Prolongado tempo de sangramento, tempo de protrombina (TP) e tempo de tromboplastina parcial ativada (TTPA) foram observados no grupo com leishmaniose visceral. Onze cães apresentaram lesões inflamatórias no fígado, predominando hepatite periportal mononuclear multifocal. Não foi observada associação entre a presença de parasitos e as anormalidades nos testes laboratoriais por correlação de Spearman. A progressão clínica na leishmaniose está associada com a ocorrência de diátese hemorrágica, que depende não só da presença do parasito, mas também do processo inflamatório, do comprometimento da resposta imunológica e da falência renal e hepática em cães sintomáticos.

Abstract Leishmania infantum chagasi liver parasite load was compared to hemostatic abnormalities, as well as to clinical, laboratorial, and histopathological findings in dogs with visceral leishmaniasis. The liver parasite load of 30 dogs L. infantum chagasi naturally-infected was evaluated by quantitative real- time PCR and the results were compared with serum biochemistry and primary and secondary hemostasis findings. Moreover, hepatic histological lesions were described in these dogs. Prolonged bleeding time, prothrombin time (PT), and activated partial thromboplastin time (APTT), were observed in the group with visceral leishmaniasis. Eleven dogs presented inflammatory liver lesions, with predominance of mild multifocal mononuclear periportal hepatitis. No association between the presence of parasites and abnormalities in screening tests was observed by Spearman’s rank correlation coefficient. The clinical progression in leishmaniasis is associated with the occurrence of hemorrhagic diathesis, which depends not only on the presence of the parasite but also the inflammatory process, compromised immunological response, hepatic and renal failure in symptomatic dogs.

Pectin and starch are edible, non-toxic, biodegradable and obtained from renewable sources. Also, have the benefit to be easily cross-linked producing hydrogels. Reactive extrusion with edible citric acid and cross linking interactions was evaluated on extruded thermoplastic in natura and cationic starch-pectin blends. Materials water susceptibility and mechanical properties were characterised. Reactive extrusion decreased (up to 75% in natura starch) mechanical properties. Also have decreased (up to 32.4%) both starch polymers water absorption, indicating the possibility of increasing materials water barrier properties but had the opposite effect on the pectin-TPS material, probably related to a cationic-anionic cross linking, resulting in a hydrogel polymer. Reactive extrusion also have negatively affected mechanical properties of both starch polymers, however increased pectin-TPS blends stress and strain at rupture.

Bionanocomposites of thermoplastic starch (TPS) reinforced with microfibrilated cellulose (MFC) were prepared by melt processing. MFC was prepared from eucalyptus wood pulp by a process combining cryogenic milling in high shear mixers, chemical treatment with sodium hydroxide and ultrasound treatment. The never dried MFC was then dispersed in native starch and glycerol and processed in a single screw extruder. Two MFC contents were incorporated, 3 and 10 wt %, based on TPS. The MFC was characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The bionanocomposites were characterized by tensile tests, SEM and water absorption experiments. Modulus and tensile strength were improved. Water absorption did not change in an appreciable way with the addition of MFC. The homogeneous dispersion of the MFC into TPS matrix can be considered one of the remarkable points of the new process used in the composite preparation.

A leishmaniose visceral canina é uma doença grave e a morte ocorre por falência renal, considerando que os métodos diagnósticos convencionais não possibilitam a classificação clínica do animal. O objetivo deste estudo foi associar a carga parasitária renal aos achados clínicos e histopatológicos em cães com leishmaniose visceral. A análise microscópica revelou predomínio de nefrite intersticial mononuclear de graus variados em 59,3% dos cães avaliados. Entretanto, não houve diferença entre a carga parasitária renal de sintomáticos e oligossintomáticos (P= 0,35). As lesões renais foram de ordem inflamatória e a quantidade de parasitos não influenciaram na característica dessas lesões e nem nas alterações bioquímicas, mesmo em cães com diferentes classificações clínicas.

Canine visceral leishmaniasis is a severe disease and the death occurs from renal failure, whereas conventional diagnostic methods do not allow the animal clinical staging. The aim of this study was to associate the renal parasite load to clinical and histopathological findings in dogs with visceral Leishmaniasis. Microscopic analysis revealed a predominance of mononuclear interstitial nephritis of varying degrees in 59, 3% of dogs evaluated. However, no difference was found between the renal parasite load of symptomatics and oligosymptomatics (P= 0,35). Renal lesions were inflammatory order and amount of parasites not influenced the characteristics of theses lesions nor biochemical changes, even in dogs with different clinical classifications.