[Polymorphism of neutral alpha glucosidase of human urine]. / Polimorfizm neitral'noi al'fa-gliukozidazy mochi cheloveka.

Multiple forms of neutral alpha-glucosidase were found in human urine. In a number of individuals three enzyme forms were detected, in other persons--four forms. The alpha-glucosidase I and 2 were present in urine as well as in kidney of some individuals, whereas in urine of other persons only alpha-glucosidase I was found. Both forms of neutral alpha-glucosidase I and 2 from human urine exhibited the maximal activity at pH 5.75 = 6.5, had a similar Km value (0.73 mM) with maltose as a substrate and did not differ in their properties from the corresponding forms of neutral alpha-glucosidase in a soluble fraction from human kidney.

[Effect of biogenic amines on glycogen degradation in isolated rat hepatocytes]. / Vliianie biogennykh aminov na degradatsiiu glikogena v izolirovannykh gepatotsitakh krysy.

Serotonin and tyramine affected dissimilarly the enzyme activity involved in degradation of glycogen in isolated rat hepatocytes. Serotonin inhibited hydrolytic enzymes acid alpha-glucosidase, alpha-amylase and amylo-1,6-glucosidase but activated phosphorylase inducing a decrease of glycogen content in cells. Tyramine inhibited acid alpha-glucosidase and amylo-1,6-glucosidase, did not affect the alpha-amylase and phosphorylase activities and increased content of glycogen in cells. Tyramine may be used as stimulator of glycogen accumulation in liver cells.

[Soluble and membrane-bound forms of neutral alpha-glucosidase in human urine in normal conditions and in kidney diseases]. / Rastvorimaia i membranno-sviazannaia formy neitral'noi alpha-gliukozidazy mochi cheloveka v norme i pri zabolevaniiakh pochek.

Soluble and membrane-bound forms of neutral alpha-glucosidase, which are immunologically similar to the corresponding forms of kidney enzymes, were found in urine of healthy persons and of patients with kidney impairments. Membrane-bound enzyme was only slightly active in urine of healthy persons and constituted 3-10% of total urine activity although the ratio of membrane-bound enzyme was simultaneously elevated under pathological conditions. The increased rate of soluble enzyme secretion was responsible for distinct activation of neutral alpha-glucosidase in urine of the patients with kidney impairments.

[Diagnostic value of determining neutral alpha-glucosidase and N-acetyl-beta-D-hexosaminidase activity in the urine in kidney pathology]. / Diagnosticheskoe znachenie opredeleniia aktivnosti neitral'noi alpha-gliukozidazy i N-atsetil-beta-D-geksozaminidazy v moche pri patologii pochek.

As shown in studies of 123 patients with various nephropathies, activities of alpha-glucosidase and N-acetyl-beta-D-hexosaminidase in urine of the patients correlated with severity and stages of these diseases; at the same time, simultaneous estimation of both enzymatic activities in urine was shown to be more informative in diagnostic of kidney impairments. Low values of correlation coefficient (r = 0.35 +/- 0.09) between daily excretion of protein and the activity of neutral alpha-glucosidase in urine showed that the enzyme activity did not depend on proteinuria and was independent test for kidney impairment. Estimation of alpha-glucosidase activity could be used for control of the therapy; the enzymatic activity in urine correlated distinctly with the clinico-laboratory patterns of the patients studied.

[Neutral alpha glucosidase in human urine as a marker of kidney impairment]. / Neitral'naia al'fa-gliukozidaza mochi cheloveka kak marker povrezhdeniia pochek.

Distinct correlation was found between the activity of neutral alpha-glucosidase in urine and the degree of kidney impairment in 76 patients and in 15 healthy persons. In the patients with non-impaired kidney functions the activity of the enzyme in urine varied within the normal limits (from 12 to 39 microM/hr/mmole of creatinine; normal value being 14.6-15.9 microM), in the patients with moderately expressed disfunction of kidney--from 40 to 79 microM/hr/mmole of creatinine. The enzymatic activity, exceeding 80 microM/hr/mmole of creatinine (up to 227 mM), was observed in cases of severe impairment of the kidney functions. High activity of alpha-glucosidase, correlating with the severity of kidney impairment was found in urine of patients with pyelonephritis albeit the content of protein was quite normal. Interrelationship between the activity of alpha-glucosidase in urine and the state of kidney functions enables to conclude that the enzymatic activity depends on the degree of kidney impairment under various pathological conditions and that estimation of the enzyme activity in urine may be important for diagnosis of kidney diseases as well as for the control of treatment efficiency.

[Transfer of the functional genes into eucaryotic cells by neutral phospholipid liposomes]. / Perenos funktsional'nykh genov v kletki éukariot s pomoshch'iu neitral'nykh fosfolipidnykh liposom.

Transfection of plasmid DNAs containing b-galactosidase gene (pQE-LacZ) or alkaline phosphatase (pCSEAP) into L929 cell line using was studied. The complexes between plasmid DNA and liposomes containing Ca ions and glycyrrhizic acid or &-tocopherol caused successful transfection of functional genes into L929 cells. The efficiency of transfection of plasmid DNAs into L929 cells using polynucleotide-metallo(II)-liposome complexes were 30-50% from the efficiency value of calcium phosphate coprecipitation transfection.

Rat liver neutral alpha-glucosidase: isolation and characterization.

Neutral alpha-glucosidase was isolated from rat liver by Sephadex G-150 gel filtration and polyacrylamide gel electrophoresis at pH 8.9. The enzyme was found to exist in two major forms: alpha-glucosidase AB and alpha-glucosidase C. The neutral alpha-glucosidase C was purified to apparent homogeneity and biochemically characterized. The enzyme form accounts for 25-30% of the total enzyme activity, has a pH optimum at 6.0-6.5 and is thermostable. The apparent Km values for alpha-glucosidase C with maltose, MUF-alpha-D-glucopyranoside and glycogen as substrates were 1.22 mM, 0.47 mM and 68.9 mg, respectively. The finding that glycogen can serve as substrate for neutral alpha-glucosidase C suggests its involvement in glycogen metabolism.