Leukocytes respiratory burst and lysozyme level in pacu (Piaractus mesopotamicus Holmberg, 1887) / Atividade respiratória de leucócitos e nível de lisozima em pacu (Piaractus mesopotamicus)

Innate immune responses are useful to determine the health status of fish and to evaluate the effect of immunomodulatory substances in fish farming. Leukocytes respiratory burst was measured in pacu (Piaractus mesopotamicus) using chemiluminescence assay and nitroblue tetrazolium (NBT) reduction assay. The nitroblue tetrazolium reduction seemed more adequate than chemiluminescence assay for leukocytes oxidative burst determination, since it was difficult to isolate the blood leucocytes for chemiluminescence assay. Plasma and serum lysozyme were measured using a turbidimetric assay. The heating of serum and plasma samples (56 ºC for 30 minutes) for complement system inactivation darkened the plasma samples and interfered in the results. The lysozyme activity in serum was higher than in plasma, suggesting that serum samples are more appropriate for the analysis. This study established protocols that can be useful tools in the study of immune mechanisms of the tropical fish pacu.

Respostas imunológicas inatas são úteis para determinar o estado de saúde de peixes e avaliar o efeito de substâncias imunomoduladoras no cultivo destes animais. A atividade respiratória de leucócitos foi medida em pacu (Piaractus mesopotamicus) através de ensaio de quimioluminescência e ensaio de redução do nitroblue tetrazolium (NBT). O ensaio de redução do nitroblue tetrazolium pareceu mais adequado que o ensaio de quimioluminescência para determinação da atividade respiratória de leucócitos, uma vez que foi difícil isolar com êxito os leucócitos do sangue para o ensaio de quimioluminescência. Lisozima sérica e plasmática foram medidas por meio de ensaio turbidimétrico. Com o objetivo de inativar as proteínas do sistema complemento, as amostras de soro e plasma foram aquecidas (56 ºC por 30 minutos). Porém, este procedimento provocou a turvação das amostras de plasma e interferiu nos resultados. A atividade de lisozima no soro foi maior que no plasma, sugerindo que amostras de soro são mais apropriadas para esta análise. Este estudo estabeleceu protocolos que podem ser utilizados como ferramentas no estudo de mecanismos imunológicos do peixe tropical pacu.

Study of leukocytic hydrolytic enzymes in patients with acute stage of coronary heart disease.

BACKGROUND: Coronary heart disease (CHD) is a major killer worldwide. Atherosclerosis, which is the basis of CHD, is believed to be an inflammatory disorder. Though various aspects of atherosclerosis are extensively studied, leukocytic hydrolytic enzymes are not studied very well with respect to CHD. AIM: This study was planned to assess changes associated with leukocytic hydrolases in CHD patients. SETTING AND DESIGN: A tertiary care hospital; case-control study. MATERIALS AND METHODS: 106 patients with acute myocardial infarction, 60 patients with unstable angina and 45 healthy controls were included in the study. Acid phosphatase, lysozyme, adenosine deaminase (ADA) and cathepsin-G levels were estimated from leukocytes. Reduced glutathione (GSH) and malondialdehyde (MDA) levels were measured. STATISTICAL ANALYSIS: Statistical comparison of data was done using student's t-test (unpaired). Correlation difference was calculated by using Pearson correlation coefficient. RESULTS: Significantly higher levels of acid phosphatase, lysozyme, ADA with lower levels of cathepsin G in leukocytes were observed in CHD group. We also found significantly higher levels of serum MDA with lower concentrations of blood GSH in CHD group. In diabetic CHD group, significantly higher levels of leukocytic acid phosphatase, lysozyme, ADA and serum MDA with lower levels of cathepsin G and blood GSH were observed. CONCLUSIONS: Our study indicates that leukocyte hydrolytic enzymes, mainly acid phosphatase, lysozyme and ADA were more active in CHD patients and may contribute to inflammation related with CHD. Its also indicates that leukocyte cathepsin-G may have antiinflammatory role.

Diagnostic value of determining the pleural and serum lysozyme levels in pleural effusions with special reference to tuberculous type

The present study was undertaken in order to examine the value of the simultaneous pleural fluid and serum lyzozyme determination in the diagnosis of tuberculous pleural effusion. Lysozyme was measured in the pleural fluid and serum of 51 patients with pleural effusions: 15 patients with tuberculous effusion [TB], 15 with malignant effusion [CA], 11 with transudates [TS] and +/- 10 with empyemas [EM]. Serum lysozyme did not show significant differences between different groups. The mean level of pleural fluid lysozymes was statistically significantly increased in tuberculous effusions and empyemas compared to malignant effusions and transudates [P

Immunoassay of serum muramidase (lysozyme) in ocular diseases.

Serum levels of muramidase activity were measured in 162 patients with different ocular diseases and 84 healthy subjects by electro-immuno-diffusion technique. We demonstrated for the first time that electro-immuno-diffusion technique could be successfully applied for the estimation of serum muramidase concentrations. Serum muramidase was found to be high in significant number of cases with granulomatous uveitis, tuberculous keratitis, central serous retinopathy and Eales' disease. Tuberculosis was presumed to be the cause in them by the process of exlusion. Patients with high serum muramidase activity were subjected to anti-tubercular treatment with a marked clinical improvement. It is suggested that high serum muramidase could be an useful parameter in deciding the line of treatment in patients with ocular diseases of uncertain etiology. Serum muramidase concentrations showed return to normal levels with the clinical improvement of the diseases with treatment. It increased again with the re-appearance of the activity of the diseases.