[Significance of participation in programs of external quality assessment in molecular diagnostic--our experience].

Harmonization of molecular diagnostic tests in laboratories in the Republic of Croatia has only just started. According to laboratory accreditation standard ISO 15189 participation in external quality assessment (EQA) schemes or programs is a prerequisite and support tool for clinical laboratory accreditation process. As there are no national quality assurance schemes yet, an European external quality assessment (EQA) scheme or program should be found.

Polymorphisms of pon1 and pon2 genes in hemodialyzed patients.

Objectives: Q192R, L55M and -108C>T polymorphisms of pon1 gene affect PON1 paraoxonase activity while S311C polymorphism of pon2 gene might be associated with coronary heart disease. The aims of this study were to determine the frequencies of Q192R, L55M, -108C>T and S311C polymorphisms in hemodialyzed patients and to examine the relationship between pon1 gene polymorphisms and PON1 paraoxonase activity in those patients.

Design And Methods: The study included 238 control subjects and 263 hemodialyzed patients.

Effect of non-genetic factors on paraoxonase 1 activity in patients undergoing hemodialysis.

Objectives: Hemodialyzed patients have lower paraoxonase 1 (PON1) activity. Higher mortality risk from cardiovascular disease observed in these patients could be due to the low antiathetrogenic activity of PON1. Understanding the mechanism that causes lower PON1 activity could provide the possibility for modulation of enzyme activity in purpose of preventing and/or decreasing development of atherosclerosis.

Applicability of common reference intervals for serum creatinine concentrations to the Croatian population.

Background: In accordance with an ongoing activity for worldwide harmonization based on traceability in laboratory methods, the goal of this study was to validate the applicability of recommended "common" reference intervals for serum creatinine concentrations using a specific enzymatic method to the Croatian population.

Methods: The reference group consisted of 240 healthy subjects (120 males and 120 females), between 18 and 74 years of age (median 57 years), who were selected in accordance with the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) recommendations. Creatinine in serum was measured using the creatinine enzymatic assay (Olympus OSR61204) that was standardized to the isotopic dilution mass spectrometry (IDMS) method and National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 967.

Effect of splenectomy and autologous spleen transplantation on the serum platelet-activating factor acetylhydrolase (PAF-AH) activity and acute phase response (APR) in a porcine model.

The aim of this study was to evaluate the inflammatory response after total splenectomy and spleen autotransplantation in a porcine model by measuring serum platelet-activating factor acetylhydrolase activity, C-reactive protein and albumin concentrations. Nineteen piglets were used in the experiment. After induction of anesthesia, animals were randomly divided into three groups: sham-operation with spleens intact (n = 6), total splenectomy (n = 6), and splenic autotransplantation (n = 7) with small fragments of the spleen autotransplanted into the greater omentum.

Toxicological assessment of P-9801091 plant mixture extract after chronic administration in CBA/HZg mice--a biochemical and histological study.

Acute, subchronic and chronic effects of the P-9801091 plant mixture extract at a dose of 20 mg/kg body mass were assessed in serum of healthy CBA/HZg mice at 24 hours, 7 days, 3 months and 6 months of treatment (experimental group), and compared with the values obtained in the control group of untreated healthy CBA/HZg mice. The P-9801091 plant mixture extract is an antihyperglycemic preparation containing Myrtilli folium (Vaccinium myrtillus L.), Taraxaci radix (Taraxacum officinale Web.

Bovine platelet-activating factor acetylhydrolase (PAF-AH) activity related to fertility.

Plasma platelet-activating factor acetylhydrolase (PAF-AH), the enzyme characterized by the association with plasma lipoproteins, degrades platelet-activating factor (PAF) as well as PAF-like oxidatively fragmented phospholipids produced during oxidative stress. Apart from pro-inflammatory properties, PAF is also related to reproductive processes and successful fertility. In order to get a better insight into the involvement of PAF-AH in the fertility of cows, the aim of the study was to determine the PAF-AH activity as well as the C-reactive protein, cholesterol and high density lipoprotein-cholesterol (HDL-C) in the serum of dairy cows throughout the pregnancy and lactation, as well as in infertile cows.

[Harmonization of laboratory medicine in Croatia].

In order to harmonize laboratory results in the field of general medical biochemistry at the national level, analytical methods and analytical quality goals based on biological criteria together with common reference intervals were recommended. The following parameters are included: general biochemical parameters (metabolites and substrates, enzymes, electrolytes, microelements, proteins, lipids), routine urine and stool analysis and laboratory haematology and coagulation. The main purpose of external quality control in medical biochemical laboratories is to ensure independent and objective evaluation of laboratory test results in order to promote harmonization and achieve a high degree of interlaboratory comparability.

Effect of acarbose on alanine aminotransferase and aspartate aminotransferase activities in the liver of control and diabetic CBA mice.

The purpose of this study was to examine the short-term effects of diet containing 0.1% (m/m) of acarbose in standard laboratory chow on specific liver enzyme activities: alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in control and diabetic CBA mice. Diabetes was induced by intravenous injection of alloxan monohydrate in a dose of 75 mg kg(-1) mouse body mass seven days before the treatment with acarbose.

Paraoxonase/arylesterase in serum of patients with type II diabetes mellitus.

The aim of this study was to determine whether the paraoxonase (PON1) status, i.e. PON1 activities and phenotypes (AA, AB and BB), and its relationship with lipid status are different in patients with type II diabetes as compared to healthy population.

Enzyme activity and AGE formation in a model of AST glycoxidation by D-fructose in vitro.

Non-enzymatic glycation as the chain reaction between reducing sugars and free amino groups of proteins has been shown to correlate with physiological ageing and severity of diabetes. The process involves oxidative steps (glycoxidation). In this paper, the effect of D-fructose as a reactive sugar on aspartate aminotransferase (AST) as a model protein was monitored by measurements of the enzyme activity and formation of fluorescent advanced glycation end products (AGEs).

Paraoxonase activity and concentration of indicators of lipids status in the serum of cardiac patients.

In this research, we measured the activity of paraoxonase (basal and activated) enzyme, and components of lipid status components (total cholesterol, LDL cholesterol, HDL cholesterol and Apo A I) in the serum of patients, undergoing bypass surgery. We also tested how the applied EKC affected changes of defined indicators. Measuring of all the given parameters was conducted prior to the operation, 90 minutes, 1.

Effect of different dialysis membranes on erythrocyte antioxidant enzyme levels and scavenger systems related to free hemoglobin in serum of hemodialysis patients.

The main objective of the present study was to analyze some aspects of the function and structure of erythrocytes with respect to hemodialysis membrane biocompatibility throughout the erythrocyte and serum antioxidant levels. The study included 36 hemodialysis patients (14 female and 22 male, age 22-79 years, median 55) treated at the Department of Nephrology and Dialysis, Split Clinical Hospital in Split, and 30 control subjects matched for age and sex. Hemodialysis was performed three times a week for 4 hours with cellulose diacetate (n = 17; 6 females and 11 males) or polysulfone (n = 19; 8 females and 11 males) membranes.