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Thorough control of risk factors is pivotal for cardiocerebrovascular diseases. As classic risk assessment accounts for only 50% of risk variability and due to the role of inflammatory processes in endothelial dysfunction and atherosclerotic plaque rupture, it is necessary to identify new biomarkers for risk prediction. In addition to the inflammatory marker high sensibility C-reactive protein (hs-CRP), lipoprotein associated phospholipase A2 (Lp-PLA2) is gaining increasing significance, since it is directly involved in the pathogenesis of atherosclerotic plaque progression. Lp-PLA2 is highly specific for vascular inflammation, has low biological variability, and plays a causative role in atherosclerotic plaque inflammation. It belongs to the group of intracellular and secretory phospholipase enzymes that can hydrolyze sn-2 phospholipid ester bond of cellular membranes and lipoproteins. Lp-PLA2 enzyme is formed by macrophages and foam cells in atherosclerotic plaque, and is associated primarily with LDL particles in blood. Lp-PLA2 that is bound to LDL is the sole enzyme responsible for hydrolysis of oxidized phospholipids (oxPL) on LDL particles. Lp-PLA2 hydrolyzes oxPL at the surface of lipoproteins, but has weak activity against non-oxPL. Lp-PLA2 is also the enzyme that hydrolyzes oxPL on HDL particles, where it may have a role in the antioxidative function of HDL. The distribution of Lp-PLA2 between LDL and HDL particles depends on the extent of Lp-PLA2 glycosylation, which may affect the activity of Lp-PLA2 in plasma. Stable atherosclerotic plaques contain few inflammatory cells and a small amount of Lp-PLA2. In contrast, unstable plaques most often do not have significant impact on arterial lumen but may be detected by its thin connective tissue cap, low collagen and high lipid content. A distinguishing factor between stable and unstable atherosclerotic plaque may also be the presence of activated inflammatory cells and increased Lp-PLA2 concentration in unstable plaque. These new insights indicate that Lp-PLA2 may be a risk factor, which is important for the formation of atherosclerotic plaque but also for its rupture. The purpose of applying markers of inflammation is to improve stratification of patients at risk, so that treatment intensity may be adjusted to the risk level. Lp-PLA2 inhibition is associated with decreased cytokines. Lipid-affecting drugs stabilize atherosclerotic plaque by reducing the central lipid core, decreasing macrophage infiltration, and thickening of the connective tissue cap. These drugs reduce Lp-PLA2 concentration and the frequency of cardiocerebrovascular events as well. Besides acting as a specific marker of atherosclerotic plaque inflammation, Lp-PLA2 has a significant prognostic value because of its direct role in the formation of rupture-prone atherosclerotic plaque, unlike classic risk factors, for example lipid measurement or vascular imaging, which do not directly estimate acute ischemic potential in the arterial wall. Studies have demonstrated correlation between increased Lp-PLA2 concentrations and enhanced risk of cardiocerebrovascular events, even after multivariate adjustment to classic risk factors. In addition to its high specificity for vascular inflammation, Lp-PLA2 concentration is stable in terms of time, unlike, for instance, CRP levels. Lp-PLA2 has been confirmed as an independent risk predictor, which is complementary to hsCRP. It could be used in clinical practice for improved risk assessment in patients with transient cardiocerebrovascular risk, particularly in those with metabolic syndrome (obese patients with mixed dyslipidemia, hyperglycemia, insulin resistance, and arterial hypertension). Lp-PLA2 levels allow for further risk stratification of high-risk patients into a very high risk group where more aggressive therapy is recommended, as well as the achievement of LDL-cholesterol levels < 2.5 or, even better, < 2.0 mmol/L as a feasible therapeutic target. Similar to hsCRP, the levels of Lp-PLA2 are reduced by lipid-affecting drugs, while its low concentrations are associated with a very low risk of cardiocerebrovascular events both in low- and high-risk population. According to recent American guidelines for assessing the risk of cardiovascular disease, Lp-PLA2 determination is recommended as an additional marker to the classic risk assessment in patients with moderate and high risk.

The use of commercial tests (Abbott) for cystic fibrosis, version 2 (CFv. 2) and 3 (CFv. 3) and analysis of reaction products by capillary electrophoresis and genotyping on an ABI PRISM 310 genetic analyzer (Applied Biosystems) are presented, along with the results of test validation by concurrent processing of DNA samples on a Light Cycler (Roche Diagnostics) and INNO-LIPA CFTR 19 multiparameter screening test (Innogenetics). The new Abbott commercial test for cystic fibrosis, CFv. 3, allows for determination of the exact number of the potential gene mutations (33 mutations). Other mutations may be present but cannot be established by using this test. Distribution frequency of CFTR gene mutations varies in populations, and this test covers the most frequent mutatiocs in the world. Based on the results obtained by validation, the use of this test is recommended for the following reasons: - the diagnosis of cystic fibrosis is reliable and relatively inexpensive since the reaction products allow for the most current analysis by means of capillary electrophoresis, and computer data processing which will soon enable routine sequencing and thereby determination of point mutations, - it is possible to use very small quantities of isolated DNA and to directly apply microvolumes of blood with EDTA, and - identification of a large number of current mutations has been made possible.

This study investigated the frequency of angiotensin-converting enzyme (ACE) genotypes, concentrations of total cholesterol (T-C), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), lipoprotein Lp (a), Established Risk Factor (ERF) ratio (total cholesterol/HDL-C), apolipoproteins A-I, A-II, apoBand apoE in 134 menopausal women aged 49.62 +/- 4.83 on oral hormone replacement therapy (HRT) (2 mg 17 beta estradiol plus 1 mg norethisterone acetate/day), during (mean +/- SD) 15.77 +/- 9.94 months. ACE genotypes of 134 menopausal women showed DD genotype in 48 (36%), ID genotype in 59 (44%), and II genotype in 27 (20%) women, with the mean body mass index (BMI) (kg/m2) of 26.34 +/- 4.02, systolic blood pressure (mm Hg) of 145.71 +/- 23.32, diastolic blood pressure of 95.28 +/- 12.88, pulse rate of 77.76 +/- 13.81, positive family history of myocardial infarction (MI) (23%) and stroke (22%); 26% were smokers and 6% consumed alcohol regularly. The mean levels of TC (mmol/l) were 5.72 +/- 1.25, TG (mmol/L) 1.63 +/- 0.82, HDL-C (mmol/L) 1.15 +/- 0.29, LDL-C (mmol/L) 3.98 +/- 1.31, lipoprotein Lp(a) (g/L) 0.16 +/- 0.24, ERF ratio 5.35 +/- 1.90, apolipoproteins (g/L): A-I 1.83 +/- 0.39, A-II 0.57 +/- 0.12, apoB 0.92 +/- 0.31, and apoE 0.08 +/- 0.04. The highest mean levels of T-C 5.89 +/- 1.40, TG 1.67 +/- 0.96, LDL-C 4.15 +/- 1.60, lipoprotein Lp(a) 0.19 +/- 0.25) apoB 0.95 +/- 0.32 and ERF ratio 5.46 +/- 2.24 were found in ID genotype, while in DD genotype HDL-C 1.11 +/- 0.28 and apo A-I 1.78 +/- 0.34 were lowest. In II genotype, the levels of apo A-II 0.56 +/- 0.11 were lowest and of apoE 0.09 +/- 0.05 highest. According to DD, ID and II genotypes and lipid, lipoprotein Lp(a), ERF ratio and apolipoprotein concentrations, there were no statistically significant differences between groups. ERF ratio in DD genotype showed a positive correlation with TG (r = 0.59) and LDL-C (r = 0.57), a slight positive correlation with apoB (r = 0.40), and a strong negative correlation with HDL-C (r = -0.73). ERF in ID genotype showed a strong negative correlation with HDL-C (r = -0.73), strong positive correlation with TG (r = 0.70), and T-C (r = 0.58), and slight positive correlation with LDL-C (r = 0.36) and alcohol abuse (r = 0.34). In II genotype, ERF ratio showed a strong positive correlation with LDL-C (r = 0.73), T-C (r = 0.70) and apoE (r = 0.58), slight positive correlation with apoB (r = 0.46) and TG (r = 0.36), and negative correlation with HDL-C (r = -0.54). Matrix correlation of DD genotypes showed the highest positive correlation between T-C and LDL-C (r = 0.91) and apoE (r = 0.45), and negative correlation between HDL-C and ERF ratio (r = 77), and LDL-C and ERF ratio (r = 0.55). In ID genotype, T-C showed a strong positive correlation between LDL-C (r = 0.75) and ERF ratio (r = 0.63), TG and ERF ratio (r = 0.73), and negative with HDL-C (r = 0.53). In genotype II, T-C showed a strong positive correlation between LDL-C (r = 0.96), ERF ratio (r = 0.71), apoB (r = 0.66) and apoE (r = 0.46). LDL-C correlated positively with ERF ratio (r = 0.72), apoB (r = 0.61) and apoE (r = 0.48). These findings indicated the frequency of ACE genotypes to differ within the group of menopausal women. Analysis of ACE genotypes showed ID genotype to be most common among menopausal women. This result indicated their intermediate risk of coronary heart disease (CHD) and myocardial infarction (MI). It has been well established that an increased risk of MI is associated with high frequency of DD genotype, and a low risk with high frequencies of II genotype. In addition to ACE polymorphism analysis, assessment of lipid, apolipoprotein, and lipoprotein Lp(a) concentrations, and of ERF ratio provides further important parameters for better understanding of the risk factors for CDH in women. In the present study, assessment of the genetic, metabolic and environmental markers pointed to an intermediate risk of CHD in menopausal women on HRT, although the mechanism underlying the disease is not clear and well understood yet.

The renin-angiotensin-aldosterone system (RAAS) has been considered one of the probable pathophysiologic mechanisms involved in disease progression. Genetic polymorphism of the RAAS has been associated with the clinical course of renal disease. One of the genetic polymorphisms is a deletion or insertion of a 287 base pair fragment in intron 16 of the angiotensin-converting enzyme (ACE) gene. It is known that ACE gene polymorphism is present in humans and that it is associated with an increased risk of cardiovascular diseases, renal disease progression and sarcoidosis. In this study, the potential significance of ACE gene polymorphism in patients with systemic lupus erythematosus (SLE) was investigated. ACE gene polymorphism was determined in 18 patients with SLE and in 21 healthy volunteers as a control group. The mean age of patients was 38.5 years. All patients had a mean follow-up of 30.7 +/- 20.2 months (range 5-95 months). ACE genotypes were determined by the method of polymerase chain reaction. Proteinuria and creatinine were also followed. The frequency of DD, ID and II genotypes was 50%, 28% and 22% in SLE patients and 25%, 50% and 25% in healthy controls, respectively. DD genotype was more common in SLE patients than in the control group. The patients with II genotype had lower proteinuria and creatinine level than those with DD genotype (p < 0.05). The time to disease remission was shorter in patients with II genotype (p < 0.05). Study results indicated an increased frequency of D allele in SLE patients. The increased ACE activity in these patients pointed to the need of further studies of ACE gene polymorphism in SLE.