Direct determination of distribution volume and disappearance rate of native creatine kinase in humans.

Distribution volume (DV) and disappearance rate (Kd) of native creatine kinase (CK), parameters needed for enzymatic estimation of infarct size, have not been characterized in humans. Values for these parameters have been determined in experimental models and extrapolated for use in humans. During hemodynamic monitoring, 100 to 150 ml of enzyme-rich plasma was collected from 10 patients with acute myocardial infarction, stored at -30 degrees C for a maximum of 6 days, and then rapidly reinfused back to the same patient after return of CK serum activity to baseline levels. After reinfusion, blood samples were obtained at 5- to 15-minute intervals for 2 hours and at 30- to 60-minute intervals for an additional 10 hours. In each specimen, total CK activity and MM-CK and MB-CK concentrations were determined by spectrophotometry and radioimmunoassay. Data were analyzed by either nonlinear least-squares approximation or the noncompartmental approach after baseline subtraction. Concentration of immunologically active molecules appeared to decline in parallel to enzymatic activity. In three patients a double exponential decay was demonstrated. All others exhibited single exponential decay, with a Kd of 0.0023 +/- 0.00057 (SD) min-1. DV averaged 3284 +/- 693 (SD) ml, 5% of body weight. There was no correlation between Kd estimated from terminal portions of CK time-activity curves following infarction and Kd calculated after reinfused plasma. It was concluded that a one-compartment model using values for Kd and a DV compatible with plasma volume is suitable for clinical application, and that true Kd cannot be determined from the terminal portion of CK time-activity curves after acute infarction.

Auto-reaction phenomenon detected by enzyme electrosyneresis in the serum of patients with viral hepatitis and other diseases with immune complexes.

The use of modified electrosyneresis by making 760 sera of healthy persons or persons suffering from various diseases with immune complexes to react with their own pronase-treated serum has shown the following results: - One of 220 sera of healthy persons, 11 were positive in ESE (5%); - Out of 123 sera of HBsAg carriers, 23 were positive (18.6%); - Out of 135 sera of patients with acute viral type B hepatitis, 132 were positive (97.7%); - Out of 168 sera of patients with acute HBsAg negative hepatitis, 127 were positive (75.5%); - 4 cases of fulminant hepatitis were all strongly positive; - 54 cases of patients with rheumatoid arthritis were 100% positive; - 2 cases of patients with systemic lupus erythematosus were positive; - Out of 6 patients with glomerulonephritis 3 were positive; - Out of 34 patients with carcinoma of various organs, 19 were positive (55.88%). The Authors believe, on the basis of the research work set forth partly in the present report, that this interaction is connected with the presence of immune complexes. The method used has been called Enzyme Electrosyneresis (ESE) and the detected antigen "Auto antigen exposed by protease and by electrosyneresis" (AEPE).

Screening of HBsAg and post-transfusional hepatitis type B.

The Authors consider the different opinions expressed about the HBsAg screening in blood donors and its usefulness in preventing post transfusional hepatitis B (PTHB). They report data on the incidence of such a disease, as observed in their transfusional experience during the last 5 years, with a comparison between results obtained after CEP and RIA screening systems. The Authors point out the results of their retrospective investigation: the transfusion blood with a low HBsAg titre showed to be more infectious than the blood with high titre. Consequently, it is necessary to use more sensitive methods for HBsAg screening and possibly to increase their sensitivity or to combine them with other methods fit to evidence further markers of virus B.

[New method for demonstrating HBs antigen saturated by its antibodies]. / Nuovo metodo per evidenziare l'antigene HBs saturato dai suoi anticorpi

The modalities for the carrying out of a technique for the detection of HBs antigen, even when it is completely saturated by the relevant antibodies, and its results are set out. The technique includes the preliminary acidification of the test serum at pH 2.4, in such a way as to detach the antibody from the antigen, subsequently, the effect of the hearing (70 degrees C) for some minutes to destroy the antibody. On the contrary, at this temperature the immunological reactivity of the antigen remains satisfactory. Subsequently the neutralization is carried out with Veronal buffer, and the HBs Ag detection is performed by radioimmunoassay.