RESUMO
Lactobacillus casei, which shows antitumoral activity mediated by the stimulation of cellular defence mechanisms, and its peptidoglycan were tested for their ability to inhibit in vitro the viability of various murine (Yac-1, P815, Ehrlich ascites tumor, mammary carcinoma) and human (K562, KB) tumor cell lines through primary cytotoxic activity. Treatment of these tumor line with L. casei or its peptidoglycan at different doses and for different times demonstrated a decrease in viability by 25-30%. This cytotoxic activity was revealed by 51Cr release, succinate dehydrogenase (SDH) activity, ATP assays and morphological alterations in the treated tumor cells. Immunoenzymatic assays (ELISA) showed a precise ratio of binding between Ehrlich ascites or YAC-1 cell membranes and peptidoglycan. This binding is discussed with regard to the structure of the peptidoglycan molecule. The results suggest that L. casei and its derivative peptidoglycan have both a stimulating activity in normal cells and an inhibiting activity in tumor cells, as has been found for other immunomodulatory complexes.
Assuntos
Lacticaseibacillus casei , Neoplasias Experimentais/terapia , Peptidoglicano/toxicidade , Trifosfato de Adenosina/metabolismo , Animais , Carcinoma de Ehrlich/tratamento farmacológico , Carcinoma de Ehrlich/metabolismo , Carcinoma de Ehrlich/terapia , Divisão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Radioisótopos de Cromo , Citotoxicidade Imunológica , Ensaio de Imunoadsorção Enzimática , Humanos , Lacticaseibacillus casei/imunologia , Leucemia Eritroblástica Aguda/tratamento farmacológico , Leucemia Eritroblástica Aguda/metabolismo , Leucemia Eritroblástica Aguda/terapia , Linfoma/tratamento farmacológico , Linfoma/metabolismo , Linfoma/terapia , Sarcoma de Mastócitos/tratamento farmacológico , Sarcoma de Mastócitos/metabolismo , Sarcoma de Mastócitos/terapia , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Peptidoglicano/metabolismo , Succinato Desidrogenase/metabolismo , Células Tumorais CultivadasRESUMO
The present research aimed at studying the action of an association of Bifidobacterium bifidum and Lactobacillus acidophilus, in controlling an experimental severe infection by Salmonella enteritidis administered in mouse per os. The behaviour of some parameters was undertaken, checking for the pH of intestinal content; the condition of the colonization in the intestinal wall by means of scanning electron microscopy and plates cultures; the presence of antibodies IgA in intestinal content; the index of mortality in the diversely treated animal's groups. The reported data show a string incidence of the administration of Bifidobacterium and Lactobacillus in increasing the animal's resistance against the lethal infection.
Assuntos
Bifidobacterium/fisiologia , Intestinos/microbiologia , Lactobacillus acidophilus/fisiologia , Salmonelose Animal/prevenção & controle , Animais , Feminino , Intestinos/ultraestrutura , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Salmonelose Animal/mortalidade , Salmonella enteritidisRESUMO
The virulence of Staphylococcus epidermidis strain slime producer was examined in an experimental model of foreign body infection in mice. In the course of this experimental infection the mice were injected with two antibiotics (clindamycin and cefazolin) active in vitro toward the Staphylococcus strain used. The results obtained after a week of antibiotic therapy show that clindamycin alone has a therapeutic action against the infection caused by S. epidermidis. Cefazolin showed a very poor therapeutic effect. The results are discussed on the basis of inflammatory reaction elicited from the foreign body and the characteristics of clindamycin in connection with the host's defense mechanisms.