Enzyme activity of circulating CD73 in human serum

2019 ◽  
pp. 257-267 ◽  
Author(s):  
Silvana Morello ◽  
Roberta Turiello ◽  
Gabriele Madonna ◽  
Aldo Pinto ◽  
Paolo A. Ascierto ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Human Serum

Column-chromatographic separation of isoenzymes of aspartate aminotransferase.

1978 ◽  
Vol 24 (10) ◽  
pp. 1805-1812 ◽  
Author(s):  
E J Sampson ◽  
S A Miller ◽  
S S McKneally ◽  
V S Whitner ◽  
W H Hannon ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Bovine Serum Albumin ◽  
Human Serum ◽  
Aspartate Aminotransferase ◽  
Chromatographic Method ◽  
Human Origin ◽  
Additional Information ◽  
Bed Height ◽  
Optimized Conditions ◽  
Column Chromatographic

Abstract We describe a column-chromatographic method for separating the mitochondrial and cytoplasmic isoenzymes of aspartate aminotransferase in human serum. Bed height of the ion exchanger, pH, and salt concentrations in the eluting buffers are shown to be variables affecting the separation of the isoenzymes. Under the optimized conditions selected for this study, a 30% increase in volume was observed in one fraction, associated with changing the salt concentration of the eluting buffer and attributed to a contraction of the DEAE-Sephadex A-50. Elution profiles (enzyme activity vs. fraction number) were examined with highly purified mitochondrial and cytoplasmic isoenzymes of human origin in bovine serum albumin and human serum. Recovery of the enzyme in the eluted fractions averaged 102% (SD, 2.0%) for specimens prepared from the purified isoenzymes and 104% (SD, 10.7%) for 38 human serum specimens. The separation technique showed linearity to catalytic concentrations in excess of 200 U/liter (reaction temperature 30 degrees C) for each isoenzyme. Additional information is presented regarding among-day precision and the effect of specimen dilution.

scholarly journals the effect of ferric oxide nanoparticles on peroxidase and catalase enzyme activity in healthy human serum

2019 ◽  
Vol 30 (1) ◽  
pp. 75
Author(s):  
Shaemaa Hadi Abdulsada
Keyword(s):  
Enzyme Activity ◽  
Human Serum ◽  
Ferric Oxide ◽  
Sol Gel ◽  
Competitive Inhibitor ◽  
Oxide Nanoparticles ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Healthy Human ◽  
Peroxidase Enzyme

الخلاصه : تم في هذا البحث تحضير الدقائق النانويه لاوكسيد الحديد باستخدام طريقه محلول الهلام من حامض الاوليك .تم دراسه حجم الدقائق النانويه بواسطه مسح المجهر الالكتروني وتحليل الجاذبيه الحراريه .تم دراسة تاثير الدقائق النانويه لاوكسيد الحديد على فعاليه انزيم الكاتليز والبيروكسيديز . اظهرت النتائج ان للدقائق النانويه المحضره تاثير تثبيطي تنافسي على انزيم البيروكسيديز ولاتنافسي على الكاتليز . Abstract: In this work ferric oxide nanoparticles were prepared by sol-gel method from oleic acid .the size of nanoparticles were studied by Scanning electron microscopy (SEM) and Thermal gravimetric analysis (TGA).the effect of ferric oxide nanoparticles on catalase and peroxidase enzyme activity in healthy human serum were studied .the results showed that ferric nanparticles acted as competitive inhibitor with peroxidase and un competitive inhibitor with catalase enzyme .

Antibiotics Used in Patients after Surgery and Effects of Human Serum Paraoxonase-I (PON1) Enzyme Activity

2019 ◽  
Vol 26 (3) ◽  
pp. 215-220 ◽  
Author(s):  
Aycan Yılmaz ◽  
Esra Dilek
Keyword(s):  
Enzyme Activity ◽  
Human Serum ◽  
Active Site ◽  
Active Agent ◽  
Cefuroxime Axetil ◽  
Inhibition Mechanism ◽  
Paraoxonase Activity ◽  
Activity Measurements ◽  
Active Substances

Background: Paraoxonase (PON; arilesterase, [EC 3.1.8.1]) is an enzyme from the group arilesterases (ARE). This enzyme is capable of hydrolyzing paraoxone which is the active metabolite of parathion, an organic phosphorus insecticide. PON activity was found to be low in individuals prone to development of atherosclerosis such as diabetes, familial hypercholesterolemia and kidney disorders. It was noted that PON enzyme activity decreases in relation to age increase in adults. PON enzyme activity is approximately half of that in newborns and premature babies. Approximately one year after birth, it reaches the adult level. It can be said that PON1 has significant role on living organisms. For this reason, many studies on interactions of PON-drugs are needed. </P><P> Objective: In this article, our aim is to investigate in vitro effects of four pharmaceutically active agents (fosfomycin, cefuroxime axetil, cefaclor monohydrate, and cefixime) which are often used in patients after surgery on human serum paraoxanase-I (PON1) enzyme activity. Methods: In this article, we purify paraoxonase-I enzyme from human serum by using ammonium sulfate precipitation (in the range of 60-80%), ion exchange and gel filtration chromatography. We use electrophoresis to check the purity of the enzyme. We investigate the paraoxonase activity of the enzyme at 412 nm the inhibition effects of the active substances. Paraoxone is used as the substrate. Activity measurements arw made at different inhibitor concentrations related to inhibitor studies and % Activity- [I] graphs are drawn for drug active substances. Lineweaver-Burk graphics are used to determine the Ki constants. Finally, to determine the types of inhibition we interpret these graphs. Results: The active agents used after surgery decreased the PON1 enzyme activity. They showed different inhibition mechanism. The inhibition mechanism of fosfomycin and cefaclor monohydrate was noncompetitive, cefixime was uncompetitive and cefuroxime axetil was a competitive inhibitor. The IC50 values for fosfomycin, cefuroxime axetil, cefaclor monohydrate, and cefixime were calculated to be 31.5 mM, 1.03 mM, 4.18 mM and 0.781 mM, respectively, and the Ki constants were determined to be 27.98 ± 12.25 mM, 2.20 ± 0.22 mM, 4.81 ± 2.25 mM and 1.12 ± 0.32 mM, respectively. The IC50 and Ki values showed that cefixime active agent has the maximum inhibition. Conclusion: In this study, we have detected that cefuroxime axetil inhibited competitively in vitro paraoxonase activity of this enzyme. According to this information, we thought that cefuroxime axetil linked to the active site of the enzyme. Fosfomycin and cefaclor monohydrate can be attached with amino acids out of the active site of the enzyme because they inhibit enzyme noncompetitively. Cefixime can be attached only to the enzyme-substrate complex because it inhibits enzyme uncompetitively.

Angiotensin Converting Enzyme Activity in Human Serum: Relationship to Enzyme Inhibitor In Vivo and In Vitro

1982 ◽  
Vol 127 (2) ◽  
pp. 396-396
Author(s):  
B.N. Swanson ◽  
M. Hichens ◽  
P. Mojaverian ◽  
R.K. Ferguson ◽  
P.H. Vlasses ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Angiotensin Converting Enzyme ◽  
Human Serum ◽  
Enzyme Inhibitor ◽  
Converting Enzyme ◽  
Angiotensin Converting Enzyme Activity

Rat Plasma Clearance Rate and Organ Distribution of β-Hexosaminidase Isoenzymes from Human Serum

1992 ◽  
Vol 38 (9) ◽  
pp. 1893-1898 ◽  
Author(s):  
A Isaksson ◽  
B Hultberg ◽  
T Jonung
Keyword(s):  
Enzyme Activity ◽  
Liver Disease ◽  
Human Serum ◽  
Enzyme Immunoassay ◽  
Clearance Rate ◽  
Plasma Clearance ◽  
Chronic Alcoholism ◽  
Rat Plasma ◽  
Organ Distribution ◽  
Rapid Clearance

Abstract beta-Hexosaminidase (EC 3.2.1.30) is markedly increased in human serum in liver disease, chronic alcoholism, and pregnancy. Knowledge of the clearance rate of plasma/serum beta-hexosaminidase is necessary to evaluate this increase. We studied the plasma clearance of beta-hexosaminidase isoenzymes (purified from human serum and placenta) after their infusion into rat circulation. A recently developed enzyme immunoassay method was used to measure the human beta-hexosaminidase isoenzymes; this method relies on both immunoreactivity and enzyme activity, so intact human isoenzymes were measured. In comparison with the placental isoenzymes (t1/2 less than 2 min), the serum forms showed a considerably slower clearance (t1/2 = 2-4 h). However, desialylation of the serum forms resulted in their rapid clearance (t1/2 less than 2 min). The organ localization of the enzyme eliminated from the circulation was investigated 24 h after infusion. Placental and native serum isoenzymes accumulated mainly in the liver and the spleen. Desialylated serum forms were almost exclusively localized to the liver.

Phosphorimetric microassay for succinyltrialanyl-p-nitroanilide-hydrolyzing enzyme activity in human serum

1986 ◽  
Vol 182 ◽  
pp. 271-274
Author(s):  
Naotaka Kuroda ◽  
Kiyoshi Zaitsu ◽  
Yosuke Okhura
Keyword(s):  
Enzyme Activity ◽  
Human Serum
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