This report describes a rapid and inexpensive colorimetric method based on biuret assay for total serum protein analysis using wax printed microzone plates and a desktop scanner. The colorimetric assay was performed in 96-microzone plates fabricated on polyester films through a wax printing protocol. The image scanning mode and the concentration of the biuret reagents were optimized to achieve the highest detectability levels. The best analytical response was obtained using the slide scanning mode as well as 4% CuSO4 and 150 mmol L-1 potassium sodium tartrate solutions. The proposed method offered linear relationship for the bovine serum albumin concentration range between 25 and 200 µmol L-1 with a limit of detection of 9.7 µmol L-1. The colorimetric approach revealed satisfactory precision (relative standard deviation values between 0.6 and 4.4%). The bioanalytical feasibility was demonstrated through the total protein analysis in serum samples collected from dogs previously diagnosed with kidney disease. The total serum protein concentrations varied from 960 ± 19 to 1661 ± 38 µmol L-1 and the achieved values revealed good accordance with those obtained through a reference method. Based on the reported results, wax printed microzone plates have demonstrated simplicity and potential to be adopted as alternative platforms for bioassays.

RESUMO: Os alimentos funcionais têm sido empregados como adjuvantes no tratamento do câncer de mama. Neste estudo avaliaram-se as respostas hematológicas e bioquímicas clínicas à ação de um alimento funcional administrado a cadelas com diagnóstico de neoplasia mamária maligna. Após a mastectomia, 16 cadelas foram divididas em dois grupos: suplementadas (S) e não suplementadas (NS) com um composto comercial contendo Saccharomyces cerevisiae, mananoligossacarídeos e nutracêuticos. Ambos grupos receberam tratamento quimioterápico com doxorrubicina e carboplatina, alternadamente, em intervalos de 21 dias, por oito sessões, totalizando 168 dias de tratamento. As avaliações clínicas e laboratoriais foram realizadas nos momentos de aplicação do tratamento. Os resultados dos perfis hematológico (hemograma, leucograma e plaquetograma) e bioquímico sérico (ureia, creatinina, albumina, bilirrubina total e direta, alanina aminotransferase, fosfatase alcalina e gama glutamiltransferase - GGT) foram analisados pelo teste de Kruskall Wallis. No grupo S comprovou-se elevação do peso corporal e não foram observados transtornos gastrointestinais ou outros sinais de alteração clínica ao longo do tratamento. Diferentemente no grupo NS, ocorreu perda de peso e alterações clínicas, como diarreia e vômito. No quadro hematológico, constatou-se leucopenia por linfopenia no grupo de cadelas NS e preservação do valores dentro dos parâmetros considerados normais para a espécie no grupo S. Dentre todas as variáveis da bioquímica clínica, constatou-se apenas a elevação da atividade sérica da GGT nos animais do grupo NS, sem alterações no grupo S. Conclui-se que cadelas com neoplasia mamária quando suplementadas com com alimento funcional imunoestimulante apresentam melhor condição clínica, hematológica e dos níveis bioquímicos, particularmente da GGT.

ABSTRACT: Functional foods have been used as adjuvant for breast cancer treatment of bitches. The aim of the present study was to evaluate hematological and clinical biochemistry response in female dogs diagnosed with malignant mammary tumors and supplemented with functional food. After the mastectomy, 16 bitches were divided into two groups: supplemented (S) and none supplemented (NS) with a commercial product of Saccharomyces cerevisiae, mannanoligosaccharides and nutraceuticals. Chemotherapy with doxorubicin and carboplatin was performed alternately at intervals of 21 days for eight sessions during 168 days of treatment. Clinical and laboratorial assessments was made at the treatment moments. The results of the hemogram (erythrogram, leukogram and platelet count) and serum biochemistry (urea, creatinine, albumin, total and direct bilirubin, alanine aminotransferase, alkaline phosphatase and gamma glutamyltransferase - GGT) were analyzed by Kruskal Wallis test. In the S group, increase body weight was observed, but gastrointestinal disorders or other clinical disorders were not detected over the treatment. In the NS group, loss of weight and clinical disorders were observed. All hematology parameters were normal in the S group; however, leukopenia and lymphopenia were detected in the bitches of the NS group. Among all the clinical biochemistry parameters tested, only serum GGT was increased in the NS group, with no changes in the S group. In conclusion, female dogs with mammary tumor supplemented with immunostimulant functional food have better clinical condition, they demonstrate normal levels of hematological and biochemical exams, particularly GGT.