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K Worowski

Publications and source records attributed to K Worowski.

At least 145 records · Page 8Linked to original sources
PubMedDate not supplied

Lactacystin inhibits cathepsin A activity in melanoma cell lines.

We describe the inhibitory effect of the proteasome inhibitor, lactacystin, on cathepsin A activity in murine melanoma cell lines. In vitro lactacystin metabolite, beta-lactone, at a concentration of 1 microM, significantly suppressed cathepsin A activity in B78 melanoma cell lysates by about 50%. Exposure of three murine melanoma cell lines with different metastatic potential to lactacystin at a concentration of 5 microM for 6 h caused a significant reduction in the carboxypeptidase activity of this enzyme, while the inhibitory activity remained unchanged for at least 12 h. Other proteasome-specific inhibitors, e.g. epoxomicin and N-benzyloxycarbonyl-Ile-Glu(O-tert-Bu)-Ala-leucinal (PSI) at a concentration of 1 microM did not affect cathepsin A activity in melanoma cell line lysates. These data support our previous proposal that lactacystin is not a specific inhibitor of the proteasome. Since cathepsin A is also a tumor-associated enzyme, further research is needed to clarify its role and the significance of its inhibition by lactacystin in tumor biology.

Acetylcysteine↗
PubMedDate not supplied

[Properties of protamine-heparin complexes].

Protamine-heparin complexes have a considerable resistance to physical factors of the environment such as a high ion strength and acid or alkaline pH. Free protamine is digested by plasmin giving products with a greatly decreased ability to form complexes with heparin and lower antiheparin action. Bound protamine, on the other hand, is resistant to the action of plasmin as a result of which the enzyme does not release heparin from the complexes.

Fibrinolysin↗
PubMedDate not supplied

[Anti-heparin activity of plasma with various low density lipoprotein content].

Anti-heparin activity correlated with LDL concentration in the plasma. Blood plasma of women in labour is characterized by the high antiheparin activity and low LDL levels. Anti-heparin activity is low and LDL levels are low in blood plasma in childhood. An effect of other factors neutralizing heparin (e.g. fibrinogen, platelet factor 4, acid alpha 1-glycoprotein, globulins, basic proteins) and differences of anti-thrombin III on plasma anti-heparin activity has been excluded. Neutralization of heparin anticoagulation activity by LDL is of clinical value. Blood LDL level should be considered, while heparin therapeutical doses are under scrutiny.

Adult↗
PubMedDate not supplied

[Effect of immunomodulating drugs on the release and activities of lysosomal proteinases of the liver of rats with ethanol poisoning].

Increased activity of cathepsin A and D in the cytosol fraction and homogenate of the liver of rats intoxicated for 4 weeks with ethanol (0.6 g/100 g of the body weight) was found. The cytosol cathepsin A and D activities were unaffected under the influence of Levamisole and isoprinosine++. Encorton reduced the activity of both cathepsins in the cytosol fraction while it did not diminish their activities in the liver homogenates. Encorton, and to a markedly lesser degree, Levamisole and isoprinosine++ caused a regression of vacuolar degeneration and of necrotic lesions and an increase in the number of glycogen granules in the livers of ethanol-intoxicated rats.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Effect of cysteine on protein metabolism in the liver of rats with ethanol-induced liver damage].

Rats intoxicated with ethanol at the dose of 0.6 g/100 g of the body weight during 4 weeks were fed on standard diet and the one containing 0.125, 0.25 and 0.5% L-cysteine. Intoxication of rats fed standard food causes an increase in the activity of cathepsin D and gamma-glutamyl-transpeptidase in the liver and an increase in the activity of alanine aminotransferase and gamma-glutamyl-transpeptidase in the blood serum. Consuming by rats food containing small and medium quantity of cysteine causes normalization of the activity of all enzymes, whereas consuming food containing large quantity of cysteine does not give such effect.

Alanine Transaminase↗