RESUMO
CONTEXT: Shark cartilage has been used for its beneficial effects on various diseases. There are evidences, that shark cartilage stimulates cellular and humoral immune responses, which makes it an anti-tumor and immunomodulator candidate. OBJECTIVE: The immunostimulatory effect of shark cartilage derived proteins on the cytotoxic activity of natural killer (NK) cells from healthy human peripheral blood mononuclear cells was studied. MATERIAL AND METHODS: The shark cartilage was extracted and its bioactive proteins were purified using ion-exchange chromatography (DE-52) and sequential fractionation on Amicon ultrafiltration membranes. The effect of each protein fraction on the modulation of cytotoxic activity of NK cells, as effectors, against K562, as target cells, was assayed by enzymatic lactate dehydrogenase test. RESULTS: The most immunostimulatory effect on the cytotoxic activity of NK cells was observed for AR10 fraction, containing proteins with molecular weight of about 14.5 kDa on the reducible discontinuous sodium dodecyl sulfate polyacrylamide gel electrophoresis. DISCUSSION: Among the examined shark cartilage derived proteins, the most immunostimulatory effects on the NK cells cytotoxicity was found for AR10 fraction with molecular weight of about 14 kDa. We propose-the direct interactions of shark cartilage derived proteins with NK cells surface receptors may lead to the enhancing in the cytotoxic activity of NK cells. CONCLUSION: Thus AR10 fraction, proteins of about 14.5 kDa, has a novel immunostimulatory effect on the NK cells activity in vitro and if confirmed by in vivo trials, it may lead to its future clinical applications as, immunotherapy of cancer, HIV, and augmentation of host immune system related immunodeficiency disorders.
Assuntos
Células Matadoras Naturais/efeitos dos fármacos , Proteínas/farmacologia , Extratos de Tecidos/farmacologia , Linhagem Celular Tumoral , Cromatografia por Troca Iônica/métodos , Citotoxicidade Imunológica/efeitos dos fármacos , Humanos , Fatores Imunológicos/imunologia , Fatores Imunológicos/farmacologia , Células K562 , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Ativação Linfocitária , Peso Molecular , Proteínas/imunologia , Extratos de Tecidos/imunologiaRESUMO
A 1 year review of 529 cases of acute appendicitis, treated at the University Hospital in 1990, was performed. Perforation rate was 23.7% and delay in diagnosis was found to be significant. Patients above 50 years of age were particularly at risk. Diagnostic error was 19.3% and it was a problem not only in young women but also in children. Temperature and rectal examinations were not found to be helpful in the diagnosis in contrast to leukocytosis. Waiting time for operation was long (median 7 hours), be it for a perforated or a nonperforated appendicitis.