10 research outputs found
Evaluation of parameters related to libido and semen quality in Zebu bulls naturally infected with Trypanosoma vivax
Immunophenotypic features of tumor infiltrating lymphocytes from mammary carcinomas in female dogs associated with prognostic factors and survival rates
<p>Abstract</p> <p>Background</p> <p>The immune system plays an important role in the multifactorial biologic system during the development of neoplasias. However, the involvement of the inflammatory response in the promotion/control of malignant cells is still controversial, and the cell subsets and the mechanisms involved are poorly investigated. The goal of this study was to characterize the clinical-pathological status and the immunophenotyping profile of tumor infiltrating lymphocytes and their association with the animal survival rates in canine mammary carcinomas.</p> <p>Methods</p> <p>Fifty-one animals with mammary carcinomas, classified as carcinomas in mixed tumors-MC-BMT = 31 and carcinomas-MC = 20 were submitted to systematic clinical-pathological analysis (tumor size; presence of lymph node and pulmonary metastasis; clinical stage; histological grade; inflammatory distribution and intensity as well as the lymphocytic infiltrate intensity) and survival rates. Twenty-four animals (MC-BMT = 16 and MC = 8) were elected to the immunophenotypic study performed by flow cytometry.</p> <p>Results</p> <p>Data analysis demonstrated that clinical stage II-IV and histological grade was I more frequent in MC-BMT as compared to MC. Univariate analysis demonstrated that the intensity of inflammation (moderate/intense) and the proportion of CD4<sup>+ </sup>(≥ 66.7%) or CD8<sup>+ </sup>T-cells (<33.3%) were not associated with worse survival rate. Multivariate analysis demonstrated that only lymphocytic infiltrate intensity ≥ 600 (<it>P </it>= 0.02) remained as independent prognostic factor. Despite the clinical manifestation, the lymphocytes represented the predominant cell type in the tumor infiltrate. The percentage of T-cells was higher in animals with MC-BMT without metastasis, while the percentage of B-lymphocytes was greater in animals with metastasized MC-BMT (<it>P </it>< 0.05). The relative percentage of CD4<sup>+ </sup>T-cells was significantly greater in metastasized tumors (both MC-BMT and MC), (<it>P </it>< 0.05) while the proportion of CD8<sup>+ </sup>T-cells was higher in MC-BMT without metastasis. Consequently, the CD4<sup>+</sup>/CD8<sup>+ </sup>ratio was significantly increased in both groups with metastasis. Regardless of the tumor type, the animals with high proportions of CD4<sup>+ </sup>and low CD8<sup>+ </sup>T-cells had decreased survival rates.</p> <p>Conclusion</p> <p>The intensity of lymphocytic infiltrate and probably the relative abundance of the CD4<sup>+ </sup>and CD8<sup>+ </sup>T-lymphocytes may represent important survival prognostic biomarkers for canine mammary carcinomas.</p
Effect of the Aedes fluviatilis saliva on the development of Plasmodium gallinaceum infection in Gallus (gallus) domesticus
Effect of the Aedes fluviatilis saliva on the development of Plasmodium gallinaceum infection in Gallus (gallus) domesticus
Effect of Aedes fluviatilis saliva on the development of Plasmodium gallinaceum experimental infection in Gallus (gallus) domesticus was studied in distinct aspects. Chickens subcutaneously infected with sporozoites in the presence of the mosquito salivary gland homogenates (SGH) showed higher levels of parasitaemia when compared to those ones that received only the sporozoites. However, the parasitaemia levels were lower among chickens previously immunized by SGH or non-infected mosquito bites compared to the controls, which did not receive saliva. High levels of anti-saliva antibodies were observed in those immunized chickens. Moreover, 53 and 102 kDa saliva proteins were recognized by sera from immunized chickens. After the sporozoite challenge, the chickens also showed significant levels of anti-sporozoite antibodies. However, the ability to generate anti-sporozoites antibodies was not correlated to the saliva immunization. Our results suggest that mosquito saliva components enhance P. gallinaceum parasite development in naive chickens. However, the prior exposure of chickens to salivary components controls the parasitemia levels in infected individuals
Bioactive endophytic fungi isolated from Caesalpinia echinata Lam. (Brazilwood) and identification of beauvericin as a trypanocidal metabolite from Fusarium sp.
Aiming to identify new sources of bioactive secondary metabolites, we isolated 82 endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro assays. The organic extracts from three isolates showed antibacterial activity against Staphylococcus aureus and Escherichia coli [minimal inhibitory concentration (MIC) 32-64 μg/mL]. One isolate inhibited the growth of Salmonella typhimurium (MIC 64 μg/mL) and two isolates inhibited the growth of Klebsiella oxytoca (MIC 64 μg/mL), Candida albicans and Candida tropicalis (MIC 64-128 μg/mL). Fourteen extracts at a concentration of 20 μg/mL showed antitumour activities against human breast cancer and human renal cancer cells, while two isolates showed anti-tumour activities against human melanoma cancer cells. Six extracts were able to reduce the proliferation of human peripheral blood mononuclear cells, indicating some degree of selective toxicity. Four isolates were able to inhibit Leishmania (Leishmania) amazonensis and one isolate inhibited Trypanosoma cruzi by at least 40% at 20 μg/mL. The trypanocidal extract obtained from Fusarium sp. [KF611679] culture was subjected to bioguided fractionation, which revealed beauvericin as the compound responsible for the observed toxicity of Fusarium sp. to T. cruzi. This depsipeptide showed a half maximal inhibitory concentration of 1.9 μg/mL (2.43 μM) in a T. cruzi cellular culture assay