Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cybulska, Janina (State Institute of Hygiene, Warsaw, Poland), and J. Jeljaszewicz. Bacteriostatic activity of serum against staphylococci. J. Bacteriol. 91:953-962. 1966.-Antistaphylococcal activity of normal serum against strains exhibiting various patterns of coagulase, clumping-factor, and staphylokinase production is not connected with the presence of these factors. Purified coagulase does not influence this property of serum. Coagulase-negative strains with clumping-factor activity grow in normal serum as typical pathogenic staphylococci. Serum bacteriostatic activity against staphylococci may be reversed by several nonspecific factors, such as sterile broth, supernatant fluids of coagulase-negative strains, and ammonium sulfate precipitates of culture supernatant fluids of various staphylococci. Immune sera with a high agglutinating titer for staphylococcal cells do not prevent growth of serum-resistant strains; serum-susceptible strains are inhibited as in normal serum control. Activation or blocking of the serum fibrinolytic system does not influence serum bacteriostatic activity. The growth rate of serum-resistant strains is identical in serum and in Todd-Hewitt broth; serum-susceptible strains are inhibited to the inoculum level, but decreases and increases in viable count are noted during a 24-hr observation period. Observations made with sera of 10 animal species clearly demonstrated differences in serum bacteriostatic activity, mouse serum being completely noninhibitory and cat serum only weakly inhibitory. The technique of quantitative determination of serum susceptibility of staphylococci is described, and the importance of serum antistaphylococcal activity in vitro is discussed. Experimental staphylococcal infection produced in rabbits by intravenous injection of different Staphylococcus aureus strains did not result in significant changes in serum antistaphylococcal activity. The technique of experimental infection used caused chronic infection, with a peak on the 14th day; this was proved by means of a newly developed 5'-nucleotidase test. At the same time, sera of infected animals exhibited slight inhibitory properties, which returned to initial values 1 week later. Infection was produced by strains recognized as nonpathogenic and was inhibited in vitro by sera from both normal and infected rabbits. It is concluded that antistaphylococcal activity of serum should be considered as an "in vitro" phenomenon, which seems to have no importance in defense mechanisms of rabbits infected intravenously with staphylococci.
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PMID:Bacteriostatic activity of serum against staphylococci. 592 70

Extracellular nucleotides are signaling molecules whose receptor-mediated effects are involved in a variety of physiological responses in mammalian tissues. An overwhelming body of data indicate that inflammatory and other immune responses can be modulated by the availability and local concentrations of nucleotides via nucleotide receptor signaling, but this is only just beginning to be investigated in the context of infectious disease. Evidence is provided here that the parasitic nematode Trichinella spiralis can catalyze the conversion and thus modulate both the availability and concentration of extracellular nucleotides by means of the following secreted exoenzymes: apyrase, 5'-nucleotidase, and adenosine deaminase. These enzymes were characterized in terms of substrate specificity, kinetic behavior, pH, divalent cation preferences, and response to a series of compounds. The secreted 5'-nucleotidase was identified as a protein with an apparent molecular mass of 67 kDa after N-terminal amino acid sequencing of the purified protein. The presence of adenosine deaminase was confirmed in the secreted products by Western blotting with an antibody against a mammalian enzyme, as a protein with an apparent molecular mass of 38 kDa. These secreted proteins constitute an enzymatic cascade which catalyzes the degradation of extracellular nucleotides, with a potential physiological role in the regulation of purinergic signaling.
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PMID:Nucleotidase cascades are catalyzed by secreted proteins of the parasitic nematode Trichinella spiralis. 1218 37

The immunocytograms of 166 patients with opiomania, primarily of the heroin variation, aged 15 to 19, were examined. 18 healthy teenagers of the same age were in the control group. The sampling comprised both patients without any signs of infectious diseases (86 persons) and patients with viral hepatitis B and C. The deviations of the immune-cellular status comprised, in drug addicts, a deficit of T-helpers and NK-cells as well as an increased quantity of "zero" lymphocytes. An essential reduction in the level of T-suppressors (killers) was additional found in the group of drug-addicts with viral hepatices. The signs of cytolysis of hepatocytes were detected in young heroin addicts. The contents of lipid peroxides was significantly higher in the blood plasma of teenagers abusing the opium drugs; while the concentration of antioxidant factor was as follows: Vitamin E, sulfhydric proteins and urate were found to be decreased. A reliable correlation was found between the changes of the quantity of T-helpers, T-suppresses (killers) and 0-lymphocytes, on the one hand, and the activity of hepatic transaminases, on the other hand, (for AST = 0.65-0.70; p < 0.01). The disorders in the immune-cellular status persist for as long as three to four weeks after the refusal from drug consumption; it is noteworthy, that their severity can essentially go up. The activity of 5'-nucleotidase, involved in the transformation of receptor signals in T- and B-lymphocytes, was histochemically studied in immunocytes. The activity of the enzyme essentially went down in both populations of lymphocytes by the 7th day of abstinence; it remained at the mentioned level up to the 14th day (in patients with hepatitis) or up to 21st day (in patients without hepatitis). Therefore, the quantitative deficit of immunocytes in drug addicts was accompanied, during the abstinence period, by an inhibition of their functional activity.
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PMID:[Disorders in the immune status and hepatic pathologies in young heroin addicts]. 1270 48