Laboratornoe delo最新文献

Hemolytic activities of Klebsiella-237 strains of various origins were measured in solid nutrient media by three methods making use of six different agar bases for the preparation of blood nutrient media. The authors analyze the agar bases, discuss the advantages and shortcomings of all the methods used with consideration for the purpose of the investigation. The findings evidence a higher hemolytic activity in Klebsiella isolated from patients as against the hemolytic activities of reference strains.

A method for manual measurement of glucose in biologic fluids has been developed, making use of glucose oxidase immobilized on a carbamide derivative of microcrystal cellulose; two variants are suggested: a rapid and a routine one. The method is characterized by a high analytical reliability, its results are in high correlation with the results of measurements by Beckman glucose analyzer (r = 0.92, p less than 0.001). The method is economic (glucose oxidase reagent may be used for more than 300 times), easily available, and is 3 to 6 times more rapid than the method with soluble glucose oxidase. It is particularly convenient for urgent laboratory diagnosis.

A chemiluminescent method has been offered to assay the blood serum total cholesterol. The method is based on coupled enzymatic reactions in two steps: (1) esterified cholesterol hydrolysis by cholesterol esterase in the presence of sodium cholate and (2) cholesterol oxidation by cholesterol oxidase and chemiluminescent assay of the released hydrogen peroxide in peroxidase reaction with luminol and p-iodophenol. Separation of these steps results in a better accuracy of the test as against the one-step procedure. High sensitivity of the method (the detection limit being 1 mM of cholesterol in a luminometer cuvette) permits high dilutions of the serum, this essentially eliminating the admixture effects on the enzymatic reactions. The findings of the suggested method are in good correlation with those of the spectrophotometric assay of cholesterol using the KONE kit.

Alkaline phosphatase and trypsin activities were measured in the gastric contents of patients with chronic gastritis with visually fixed duodenogastric reflux and without reflux. The authors discuss the advantages of a comparative approach to the enzymatic assessment of duodenogastric reflux presence, intensity, and length.

When commercial erythrocytic diagnostic agents, prepared from sheep red cells, are used in the passive hemagglutination test with blood sera from patients with intestinal infections, the possibility of nonspecific reactions with heterophilic antibodies of human body should be borne in mind. To completely eliminate these antibody effects on the results of the test, titration of the tested serum should be started from 1:64, 1:80, or 1:100, depending on what titration scale is used.

Blood antioxidant system parameters were examined in elderly subjects. The authors have developed methods for measurements of catalase, superoxide dismutase, and lipid peroxidation products. They introduce a new factor 'F' that is supposed to characterize the blood antioxidant system; this factor is based on the values of catalase and superoxide dismutase activities and the intensity of lipid peroxidation. The authors come to a conclusion that the blood antioxidant and oxidant systems may be more accurately described with the use of this new factor F. In case of an abdominal tumor whole blood catalase level is elevated and superoxide dismutase activity significantly reduced. Factor F values were found extremely low before death, therefore this factor may be considered an important criterion of a critical state. The blood antioxidant parameters of patients with diabetes mellitus and essential hypertension did not much differ from those of age-matched healthy subjects.

The authors suggest a method of functional probing of the complement alternative cascade, the jist of it being analysis of the neutrophil adhesion to sephadex granules treated with serum or another complement-containing substrate. The advantages of the method are analyzed, and the range of its application suggested.

A method for serial measurements of blood serum acid DNAse (3.1.4.5) and acid RNAse (3.1.4.23). The authors recommend measurements of acid nucleases at clinical biochemistry laboratories and use of these parameters for the prediction of outcomes of balneotherapy and other treatment modalities.