Gallium maltolate, a promising low toxicity drug with curative effect on mice chronically infected with Trypanosoma evansi

Trypanosoma evansi is a flagellate protozoan that infects a wide range of hosts, especially horses. Clinically, the infection is characterized by rapid weight loss, anemia and mobility disorders. This study evaluated the efficacy of treatment gallium maltolate (GaM) in rats infected with T. evansi in the acute and chronic phases of the disease and its influence on the enzyme and blood parameters. 48 animals (Rattus norvegicus) were divided into 8 groups (A-H) of 6 animals each, namely: A: (negative control) uninfected; B: acutely infected positive control; C: chronically infected positive control; D: acutely infected, treated with GaM for 7 days post infection (p.i.); E: acutely infected treated with GaM for 3 days before infection (b.i) and 7 days p.i.; F: chronically infected, treated with GaM for 7 days p.i.; G: chronically infected, treated with GaM for 3 days b.i. and 7 days p.i.; and H: uninfected treated with GaM for 10 days. Acute infected animals (B, D and E) had a progressive increase in parasitemia and were died or euthanized before completing treatment days (5th days p.i.) as they had high parasitemia (over 100 field trypanosomes in the blood smear). Thus, it can be concluded that GaM was not effective against an acute infection. In untreated chronically infected animals (C) the parasitemia also increased progressively and they were euthanized on the 7th day p.i.. The chronically infected and treated animals (F and G) showed low parasitemia and after treatment became negative, showing no trypanosomes in the bloodstream until the 50th day of the experiment. Thus, we conclude that GaM was effective against chronic infections. In uninfected and treated animals (H) hematological, biochemical and enzymatic parameters had no significant changes when compared to the negative control group (A) demonstrating the low toxicity of GaM.

HELMINTOS INTESTINAIS EM CÃES DOMICILIADOS E ASPECTOS SOCIOECONÔMICOS E CULTURAIS DAS FAMÍLIAS PROPRIETÁRIAS DOS ANIMAIS DE LAGES, SC, BRASIL

Com os objetivos de determinar a prevalência de helmintos intestinais em cães domiciliados nas regiões central e periférica de Lages, SC, de correlacionar aspectos socioeconômicos e culturais das famílias proprietárias dos animais com a prevalência observada e de verificar a proporção entre a população humana e canina, no período de dezembro de 2005 a dezembro de 2006, foram aplicados 600 questionários a pessoas residentes em cinco bairros da região central e cinco da região periférica da cidade de Lages, SC. Foram coletadas amostras de fezes de 523 cães, que foram processadas por técnicas de flutuação e sedimentação. Dados de faixa salarial e escolaridade foram utilizados para avaliação dos aspectos socioeconômicos e culturais, respectivamente. Para a mensuração das populações humana e canina foram computados todos os cães existentes nos domicílios. A prevalência para helmintos intestinais foi de 38,2%, sendo maior em cães domiciliados na região periférica. Os níveis socioeconômico e cultural não foram significantes para a prevalência de helmintos intestinais em cães. A proporção homem/cão foi de 3,5:1 e para a cidade de Lages, foi estimada uma população de 44.780 cães domiciliados.

Susceptibility of Trypanosoma evansi to propolis extract in vitro and in experimentally infected rats

Current therapy of Trypanosoma evansi infections is not effective for the vast majority of animals with relapsing parasitemia and clinical signs. Recently, attention is being focused on the antiparasitic activity of propolis. This study evaluated the susceptibility of T. evansi to propolis extract in vitro and in vivo. A dose-dependent trypanocidal activity of propolis extract was observed in vitro. All trypomastigotes were killed 1 h after incubation with 10 μg mL(-1) of the extract. In vivo, the concentrations of 100, 200, 300 and 400 mg kg(-1) administered orally for 10 consecutive days showed no curative effect, and the rats died from the disease. However, rats treated with the two highest concentrations of propolis extract showed higher longevity than the other groups. Based on these data, we concluded that T. evansi is susceptible to propolis in vitro. Despite the lack of curative efficacy observed in vivo at the concentrations tested, the propolis extract can prolong life in rats infected with the protozoan.

Toxoplasma gondii antibodies on domiciled cats from Lages municipality, Santa Catarina State, Brazil

Sera were collected from 300 domiciled cats from the municipality of Lages, Southern Brazil, to determine the prevalence of Toxoplasma gondii antibodies and risk factors associated. Tests for T. gondii antibodies were performed using indirect immunofluorescent antibody test (IFAT). Positive reactions with titers >1:64 were found in 43 (14.33%) cats. A significant number of seropositive cats were >6 month old (p = 0.03758) and had access to the streets or/and rural areas (p = 0.04185). The results indicate that T. gondii is widespread in cats in Lages with a prevalence of 14.33%.