Hypertension and its correlation with renal lesions in dogs with leishmaniosis

To evaluate the prevalence of hypertension and its correlation with the severity of renal injury and proteinuria in dogs with leishmaniosis, sixty-six dogs were divided into two groups. Group 1 (G1) was composed of 54 dogs included in stage 1 of chronic kidney disease (CKD), and group 2 (G2) of twelve dogs in stages 2 and 3 of CKD. Prevalence of hypertension was 28.8%, comprising 22.2% of the dogs from G1 and 58.3% from G2 (P=0.011). The mean arterial blood pressure (BP) of dogs from G1 (135.7 +/- 20.5) was lower than from G2 (170.0 +/- 26.3) (P <0.001). Urine proteincreatinine ratio (UP/C) revealed values above 0.5 in 75.7% of the dogs, with 34% presenting hypertension. All dogs with hypertension had histopathological and laboratory evidence of glomerular disease. Although there was no statistically significant correlation between elevated BP and the severity of glomerular lesions (P=0.408), there was a statistically significant correlation between elevated BP and increased UP/C in the studied population (P=0.002). Thus, dogs with leishmaniosis and renal disease must be screened for the presence of hypertension so that treatment may be instituted as early as possible, in countries where treatment is allowed, to prevent the progression of renal damage.

Recombinant hepatitis C virus-envelope protein 2 interactions with low-density lipoprotein/CD81 receptors

Hepatitis C virus (HCV) envelope protein 2 (E2) is involved in viral binding to host cells. The aim of this work was to produce recombinant E2B and E2Y HCV proteins in Escherichia coli and Pichia pastoris, respectively, and to study their interactions with low-density lipoprotein receptor (LDLr) and CD81 in human umbilical vein endothelial cells (HUVEC) and the ECV304 bladder carcinoma cell line. To investigate the effects of human LDL and differences in protein structure (glycosylated or not) on binding efficiency, the recombinant proteins were either associated or not associated with lipoproteins before being assayed. The immunoreactivity of the recombinant proteins was analysed using pooled serum samples that were either positive or negative for hepatitis C. The cells were immunophenotyped by LDLr and CD81 using flow cytometry. Binding and binding inhibition assays were performed in the presence of LDL, foetal bovine serum (FCS) and specific antibodies. The results revealed that binding was reduced in the absence of FCS, but that the addition of human LDL rescued and increased binding capacity. In HUVEC cells, the use of antibodies to block LDLr led to a significant reduction in the binding of E2B and E2Y. CD81 antibodies did not affect E2B and E2Y binding. In ECV304 cells, blocking LDLr and CD81 produced similar effects, but they were not as marked as those that were observed in HUVEC cells. In conclusion, recombinant HCV E2 is dependent on LDL for its ability to bind to LDLr in HUVEC and ECV304 cells. These findings are relevant because E2 acts to anchor HCV to host cells; therefore, high blood levels of LDL could enhance viral infectivity in chronic hepatitis C patients.

A new heterologous fibrin sealant as scaffold to recombinant human bone morphogenetic protein-2 (rhBMP-2) and natural latex proteins for the repair of tibial bone defects

Tissue engineering has special interest in bone tissue aiming at future medical applications Studies have focused on recombinant human bone morphogenetic protein-2 (rhBMP-2) and natural latex proteins due to the osteogenic properties of rhBMP-2 and the angiogenic characteristic of fraction 1 protein (P-1) extracted from the rubber tree Hevea brasiliensis. Furthermore, heterologous fibrin sealant (FS) has been shown as a promising alternative in regenerative therapies. The aim of this study was to evaluate these substances for the repair of bone defects in rats. A bone defect measuring 3 mm in diameter was created in the proximal metaphysis of the left tibia of 60 rats and was implanted with rhBMP-2 or P-1 in combination with a new heterologous FS derived from snake venom. The animals were divided into six groups: control (unfilled bone defect), rhBMP-2 (defect filled with 5 mu g rhBMP-2), P-1 (defect filled with 5 mu g P-1), FS (defect filled with 8 mu g FS), FS/rhBMP-2 (defect filled with 8 mu g FS and 5 mu g rhBMP-2), FS/P-1 (defect filled with 8 mu g FS and 5 mu g P-1). The animals were sacrificed 2 and 6 weeks after surgery. The newly formed bone projected from the margins of the original bone and exhibited trabecular morphology and a disorganized arrangement of osteocyte lacunae. Immunohistochemical analysis showed intense expression of osteocalcin in all groups. Histometric analysis revealed a significant difference in all groups after 2 weeks (p < 0.05), except for the rhBMP-2 and FS/rhBMP-2 groups (p > 0.05). A statistically significant difference (p < 0.05) was observed in all groups after 6 weeks in relation to the volume of newly formed bone in the surgical area. In conclusion, the new heterologous fibrin sealant was found to be biocompatible and the combination with rhBMP-2 showed the highest osteogenic and osteoconductive capacity for bone healing. These findings suggest a promising application of this combination in the regeneration surgery.

Coinfection by toxoplasma gondii and leishmania spp. in domestic cats (Felis catus) in State of Mato Grosso do Sul

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The putative Leishmania telomerase RNA (leishTER) undergoes trans-splicing and contains a conserved template sequence

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Study on coinfecting vector-borne pathogens in dogs and ticks in Rio Grande do Norte, Brazil

Since dogs presenting several vector borne diseases can show none or nonspecific clinical signs depending on the phase of infection, the assessment of the particular agents involved is mandatory. The present study aimed to investigate the presence of Babesia spp., Ehrlichia spp., Anaplasma spp., Hepatozoon spp. and Leishmania spp. in blood samples and ticks, collected from two dogs from Rio Grande do Norte showing suggestive tick-borne disease by using molecular techniques. DNA of E. canis, H. canis and L. infantum were detected in blood samples and R. sanguineus ticks collected from dogs. Among all samples analyzed, two showed the presence of multiple infections with E. canis, H. canis and L. infantum chagasi. Here we highlighted the need for molecular differential diagnosis in dogs showing nonspecific clinical signs.

Serological detection of Toxoplasma gondii, Leishmania infantum and Neospora caninum in cats from an area endemic for leishmaniasis in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Pathology of dogs in Campo Grande, MS, Brazil naturally co-infected with Leishmania infantum and Ehrlichia canis

Different parasites that commonly occur concomitantly can influence one another, sometimes with unpredictable effects. We evaluated pathological aspects of dogs naturally co-infected with Leishmania infantum and Ehrlichia canis. The health status of the dogs was investigated based on histopathological, hematological and biochemical analyses of 21 animals infected solely with L. infantum and 22 dogs co-infected with L. infantum and E. canis. The skin of both groups showed chronic, predominantly lymphohistioplasmacytic inflammatory reaction. The plasmacytosis in the lymphoid tissues was likely related with the hypergammaglobulinemia detected in all the dogs. The disorganization of extracellular matrix found in the reticular dermis of the inguinal region and ear, characterized by the substitution of thick collagen fibers for thin fibers, was attributed to the degree of inflammatory reaction, irrespective of the presence of parasites. In addition, the histopathological analysis revealed that twice as many dogs in the co-infected group presented Leishmania amastigotes in the ear skin than those infected solely with Leishmania, increasing the possibility of becoming infected through sand fly vectors. Our findings highlight the fact that the health of dogs infected concomitantly with L. infantum and E. canis is severely compromised due to their high levels of total plasma protein, globulins, alkaline phosphatase and creatine kinase, and severe anemia.

Production of recombinant EMA-1 protein and its application for the diagnosis of Theileria equi using an enzyme immuno assay in horses from São Paulo State, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The use of a mixture of somatic and culture filtrate antigens in the evaluation of the immune response to Paracoccidioides brasiliensis

Three Paracoccidioides brasiliensis antigens, namely a culture filtrate preparation, a somatic antigen and a mixture of equal parts of the two, were tested by two serological techniques against sera from patients with paracoccidioidomycosis, and in an in vivo delayed hypersensitivity model in mice. The antigen mixture was more sensitive than the two individual antigens for the evaluation of humoral and cellular immune response to P. brasiliensis, both in man and in experimental animals.

Vaccination of sheep and cattle against haemonchosis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Facing Hymenoptera venom allergy: from natural to recombinant allergens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Trypanosoma cruzi and Its soluble antigens induce NET release by stimulating toll-like receptors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

First detection of Leishmania spp. DNA in Brazilian bats captured strictly in urban areas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The 2',4'-dihydroxychalcone could be explored to develop new inhibitors against the glycerol-3-phosphate dehydrogenase from Leishmania species

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)