Predrag Djordjevic

Prothrombogenic factors and reduced antioxidative defense in children and adolescents with pre-metabolic and metabolic syndrome.

Abstract Background: The aim of this study was to examine prothrombogenic factors and antioxidative defense in obese children and adolescents with pre-metabolic and metabolic syndrome, and to analyze insulin secretion and resistance, early glycoregulation disorders and lipid status. Methods: Insulin sensitivity was determined using the homeostasis model assessment for insulin resistance (HOMA-IR), while insulin secretion was determined using the homeostasis model assessment β (HOMA-β). Prothrombogenic factors analyzed were plasma plasminogen activator inhibitor-1 (PAI-1) and fibrinogen. Superoxide dismutase and glutathione peroxidase were measured as markers of antioxidative defense. Results: Patients with metabolic syndrome were characterized with increased body mass index (BMI), waist circumference, and HOMA-IR and HOMA-β levels, and all had increased blood pressure and triglyceride levels, low high-density lipoprotein cholesterol levels, increased PAI-1 levels and reduced antioxidative defense levels. Patients with pre-metabolic syndrome had higher levels of basal and mean insulinemia during an oral glucose tolerance test, higher levels of HOMA-β and lower levels of antioxidative defense compared to patients with metabolic syndrome. Conclusions: Negative correlations between antioxidative defense parameters and BMI, abdominal obesity, insulin secretion, systolic blood pressure and atherogenic lipid factors, as well as correlations between PAI-1 and insulin resistance and basal glycemia in the metabolic syndrome group contribute to accelerated atherosclerosis. Positive correlations between PAI-1 and waist circumference and BMI, and negative correlations between BMI and antioxidative defense in the pre-metabolic syndrome patients show that this early stage preceding the metabolic syndrome is also characterized by atherosclerotic complication risks and evident hyperinsulinism and insulin resistance. Clin Chem Lab Med 2007;45:1140–4.

Characterisation of dietary fibre components in cereals and legumes used in Serbian diet

The typical Serbian diet is characterised by high intake of cereal products and also legumes are often used. The content of total fibre as well as certain fibre fractions was determined in cereals, cereal products, and cooked legumes. The content of total fibre in cooked cereals and cereal products ranged from 2.5 to 20.8 g/100 g, and in cooked legumes from 14.0 to 24.5 g/100 g (on dry matter basis). Distribution of analysed fibre fractions and their quantities differed significantly depending on food groups. Fructans and arabinoxylans were the most significant fibre fractions in rye flakes, and β-glucan in oat flakes, cellulose and resistant starch were present in significant amounts in peas and kidney beans. When the size of regular food portions was taken into consideration, the best sources of total dietary fibre were peas and kidney beans (more than 11 g/serving). The same foods were the best sources of cellulose (4.98 and 3.56 g/serving) and resistant starch (3.90 and 2.83 g/serving). High intake of arabinoxylans and fructans could be accomplished with cooked wheat (3.20 g and 1.60 g/serving, respectively). Oat (1.39 g/serving) and barley flakes (1.30 g/serving) can be recommended as the best sources of β-glucan.

Glycated hemoglobin in hypoglycemia

The effect of hypoglycemia--caused by hyperinsulinism in insulinoma patients and in diabetic patients with frequent episodes of hypoglycemia--on glycated hemoglobin was studied. The amount of sugar bound to total hemoglobin in hypoglycemia samples was found to be significantly lower than in those which were normal or hyperglycemic. The amount of total HbA1 fraction, as determined by the mini-column method, was significantly higher than expected on the basis of the corresponding values for total glycated hemoglobin. Evidence is presented to show that this is due to the formation of a hitherto unrecognized HbA1 constituent(s) denoted here as HbA1x.

Assessment of the ISO 9001 functioning on an example of relations with suppliers development: empirical study for transitional economy conditions

In this paper, a model for the development of relationships with suppliers in order to create long-term partnerships, while following the requirements of ISO 9001 standard, was defined. Research has shown that the same relations with suppliers that exist between standardised companies (SC) and non-standardised companies (NSC) within the set of suppliers, also exist between NSC and NSC within the set of companies. Creating partnerships between SC and NSC suppliers is not possible, while obtained results show the opposite, which clearly indicates that the certification in the studied economy is being performed pro forma.

Effect of the Slag Basicity on the Coefficient of Distribution Between Copper Matte and the Slag for Certain Metals

This paper presents the results of investigation of the effect of slag composition and the slag basicity, in the process of smelting of sulfide copper concentrate, on the distribution coefficient ( ) for the following elements: Cu, Bi, Co, Au, Ag, Zn, Pb, Ni, As, Sb, Se, and Te. The research was conducted under the industrial operating conditions of the copper smelter in Bor, Serbia. High values for the coefficient of determination (R 2 > 0.6) for the dependence on the slag composition were obtained, which presents a high degree of fitting. In the case of the dependence of on the slag basicity, obtained R 2 values were much lower, due to the much smaller statistical sample.

Episodes of extremely high concentrations of SO2 and particulate matter in the urban environment of Bor, Serbia.

This paper presents the extremely high concentrations of SO2 and particulate matter measured in the urban area of the town Bor (Serbia) during August 2011. Concentrations of SO2 above 125 μg m(-3) and concentrations of particulate matter above 200 μg m(-3) recorded over several days indicate significant risk to human health and the ecosystem in this region.

ANFIS-Based Prediction of the Decomposition of Sodium Aluminate Solutions in the Bayer Process

This article presents the results of nonlinear statistical modeling of the decomposition process of sodium aluminate solution, as part of the Bayer technology for the production of alumina. Based on the data collected in 2011 and 2012 from industrial production in the Birač Alumina Factory, Zvornik (Bosnia and Herzegovina), nonlinear statistical modeling of the industrial processes was derived. The model was developed as an attempt to define the dependence of the degree of decomposition of sodium aluminate solution as a function of the input parameters of the leaching process: caustic ratio (αk) of the solution; ratio of the crystallization; content of Na2O(caustic) in the solution; the initial temperature of the solution; the final temperature of the solution; average diameter of the crystallized seeds; and duration of the crystallization process. As a tool for statistical modeling, Adaptive Network Based Fuzzy Inference System (ANFIS) was applied. The defined model using ANFIS methodology expressed a high level of fitting, and could be used to effectively predict the degree of decomposition of the sodium aluminate solution as a function of the input process under industrial conditions.

Multi-Criteria Decision Support System for Optimal Blending Process in Zinc Production

The formation of input batch zinc concentrates is one of the key processes on which the quality and efficiency of all subsequent operations during the production of zinc cathodes directly depends. The optimization of the formation of a mixed batch aims at making a selection between the zinc concentrates that have different contents of useful and harmful components and to determine their share in the optimal mix. A multi criteria optimization model, which can be a good support for the defined problem of determining the optimal mixture of zinc concentrates, was developed in this study. For an evaluation of this model, according to four different research scenarios, the PROMETHEE/GAIA methodology was used to rank the considered zinc concentrates and determine their optimal share in the mix batch. In addition, the determination of the significance of the criteria in the optimization model was performed by application of the subjective AHP approach and the objective entropic approach. The results of this study, which were obtained during an analysis of a real case from the practice of a zinc production facility, indicate that the choice and formation of the optimal mixture of concentrates directly depends on the subjective or objective type of assessment of the significance of several chemical components in the zinc concentrates, and on the market price of the considered concentrates.

Liver function test changes in centrally obese youth with metabolic syndrome in a Serbian population.

OBJECTIVE The aim of this study was to investigate the association between metabolic syndrome and liver enzymes in overweight and obese adolescents and young adults. METHODS A total of 126 overweight and obese adolescents and young adults (age, 15-26 years), 55 (43.6%) with metabolic syndrome and 71 (56.4%) without metabolic syndrome, were studied. RESULTS Patients with metabolic syndrome had significantly higher alanine aminotransferase (ALT), γ-glutamyl transpeptidase (GGT), and alkaline phosphatase (ALP) levels compared to patients without metabolic syndrome [36.5±22.2 vs. 29.4±17.8 IU/L (P=0.043), 33.8±17.8 vs. 26.9±18.4 IU/L (P=0.002), and 84.3±32.2 vs. 75.7±29.5 IU/L (P=0.063)]. Aspartate aminotransferase (AST) levels were similar in both groups (24.1±9.8 vs. 23.3±9.0 IU/L, P=0.674). Elevated AST, ALT, GGT, and ALP levels were observed in 6, 15, 18, and 5 patients (11%, 27%, 14%, and 9%) with metabolic syndrome compared to 6, 17, 6, and 4 (8%, 24%, 8% and 5%) patients without metabolic syndrome (P=0.872, P=0.826, P<0.001, and P=0.035). In multivariate regression models adjusted for age and gender, metabolic syndrome was not a significant predictor of ALT (P=0.967), GGT (P=0.526), and ALP levels (P=0.221), but insulin resistance was a significant predictor for ALT and GGT levels (P=0.001, P=0.028). CONCLUSION Changes in liver function tests were observed in obese patients with metabolic syndrome, compared to patients without metabolic syndrome, especially in ALT and GGT levels. Insulin resistance is an independent pathogenic mechanism in liver function test changes regardless of metabolic syndrome in nondiabetic centrally obese youth.

Impact of leadership on strategic planning of quality

This paper presents the results of an empirical investigation of the impact of leadership on strategy of quality planning in manufacturing companies with a certified Quality Management System (QMS) according to the requirements of ISO 9001, in the southern Serbia. Theoretical structural model and hypothesis of the impact of leadership on the elements of strategy of quality planning were defined. Path coefficients in the structural model were determined using LISLER v.16 software, which proved the defined hypothesis, except the hypothesis regarding customers and suppliers involvement in quality planning. Based on the results of the empirical research performed in this paper it is shown that under the conditions of transitional economy, under which Serbian companies have been operating for over two decades, QMS certification according to the requirements of ISO 9001 has been conducted pro forma and it does not function according to the guidelines of this standard within the suppliers – company – customers supply chain.