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European inland waterways are a key element of the European transport network and are mostly used for freight traffic. The hydrographic surveying is the basis for the maintenance of inland waterways and the establishment of safe navigation. A part of the European waterway corridor E80 consists of the rivers Danube, Sava and Tisza, which part of their course also flows through the Republic of Serbia. On these sections of the mentioned rivers, the competent state institutions are conducting a continuous campaign of hydrographic measurements, which, among other things, includes GNSS RTK positioning and depth measurement with a single-beam ultrasonic echo sounder. In this paper, the characteristics of these sections of rivers, the current methodology of depth measuring and positioning during depth measuring will be shown in details.

The aim was to detect and correlate anticancer effects of metformin in combinations with other repurposed drugs, already registered for other indications, which may be immediately applied and clinically investigated in oncology, reducing the time and cost of research for new cancer treatments. Immunohistochemistry was performed for tumors treated by dual drug combinations containing metformin with deoxycholic acid, caffeine, itraconazole, nitroglycerin, disulfiram or diclofenac. The drugs were applied in Syrian golden hamsters (6 animals per group) with the inoculated BHK21/C13 fibrosarcoma in doses equivalent to usual human doses,

Introduction/Objective. Many drugs registered for various other indications can act selectively on tumor receptors, signaling pathways, metabolic processes, bioenergetic factors, enzymes, proteins and genes that regulate tumor proliferation, apoptosis, and neoangiogenesis without affecting these activities in healthy cells. Introduction of new drugs is a very long, complex, and expensive process of research. Detecting an anticancer effect in drugs already registered for other indications and forming their combinations may directly reduce the time and cost of such research. Methods. Anticancer efficacy of metformin and its combinations with caffeine, itraconazole and nitroglycerin was tested on fibrosarcoma experimentally induced by BHK21/C13 cells in Syrian golden hamsters (six animals per group, randomly allocated to control and experimental groups, doses equivalent to usual human doses). After animal sacrifice, tumors were excised and their size, biophysical characteristics, histology, and immunohistochemistry were assessed. Blood samples were collected for hematological and biochemical analyses and the main organs were toxicologically analyzed. Statistical significance was determined by one-way ANOVA followed by the Student–Newman–Keuls post hoc test. Results. Two-drug combinations of metformin with caffeine or itraconazole or nitroglycerin showed significant antitumor effects on hamster fibrosarcoma compared to control, regarding all tested tumor parameters (p < 0.05) without toxicity. Conclusion. Administration of metformin in combination with caffeine or itraconazole or nitroglycerin might be an effective and safe approach in novel nontoxic adjuvant anticancer treatment.

Introduction/Objective. Large diversity in molecular mechanisms of cancer regulation allows some marketed pleiotropic non-oncological non-toxic pharmaceuticals to be used in oncology, which reduces duration and cost of novel anticancer treatment research. To date, there are no published in vivo results on anticancer effects of certain combinations of non-oncological pleiotropic drugs (disulfiram, metformin, deoxycholic acid, mebendazole) that influence MAPK/PI3K/AKT/mTOR/NF-κB signaling. Methods. The anticancer effects of certain aforementioned repurposed drugs combinations, < 50 % LD50 (equivalent to the usual human dose) were assessed by fibrosarcoma growth kinetics (measured daily in vivo by calipers) and tumor proliferation (Ki-67, PCNA), neoangiogenesis (CD34, CD31), glucose metabolism (GLUT1), NO metabolism (iNOS) and apoptosis (COX4, cytochrome C) in hamsters, randomly allocated to control and experimental groups (six animals per group). The animals were sacrificed 19 days after BHK-21/C13 tumor inoculation. The tumors were excised, measured, and blood was collected. Biophysical, pathohistological, toxicological, hematological, and biochemical analyses were performed. Results. Disulfiram with metformin, disulfiram with deoxycholic acid and deoxycholic acid with metformin are the combinations that have shown significant antitumor effects on the fibrosarcoma growth kinetics and tumor immunohistochemical markers in hamsters (p < 0.05). All used drugs in efficacious combinations can inhibit MAPK/PI3K/AKT/mTOR/NF-κB signaling. The addition of NF-κB stimulator mebendazole to effective two-drug combinations rescued cancer growth, indicating that these pathways may be responsible for antitumor action. Conclusion. Combinations of non-oncological drugs: disulfiram with metformin, disulfiram with deoxycholic acid and deoxycholic acid with metformin have the potential to be used as effective non-toxic adjuvant anticancer therapy in oncology.

Introduction. Alzheimer's disease is the most common form of dementia. Apraxia can be one of the symptoms of Alzheimer's disease. Apraxia is defined as an acquired deficit in the execution of movements that cannot be explained by motor or sensory impairments. Aim. The main aim of this research is to determine the types of apraxia in people with Alzheimer's dementia and to point out the importance of early rehabilitation of these patients. Method. The sample consists of 15 patients with Alzheimer's dementia (amnestic type - multiple domains) aged from 50 to 85 years. In addition to the free interview, which follows predetermined principles, a neurological clinical assessment of motor skills and sensitivity and a neurobehavioral assessment of appearance, behavior, and emotions were conducted. The examination was conducted according to the established criteria at the Antamedica Polyclinic in Belgrade. Results. The results of our study show that patients with Alzheimer's disease are impaired in both the first and second stages: time orientation, attention, arithmetic, remembering, naming, writing, and copying figures. On the other hand, other cognitive functions are relatively well preserved in these stages of the disease. Patients with Alzheimer's disease have an impaired ability to understand spoken and written language. In contrast, no deficits were found on the verbal-visual discrimination test. Conclusion. Assessment of apraxia has become an important aspect of neurodegenerative diseases and a main indicator for psychotherapy and occupational therapy, contributing to the quality of life of the elderly, primarily with cognitive decline.

In the new hall of the Institute for Materials and Structures, there was a need to control the geometry of the existing crane rails. In this paper, the methodology for determining the geometry of such a complex structure is presented, and the results of the applied method are also presented. The final product, i.e. the examined geometry of crane rails included numerical and graphical analysis of straightness, analysis of parallelism and analysis of horizontality of crane rails.

The correct conclusion about the assumptions concerning some phenomena can be obtained only through scientific analysis of statistical data. The scientific procedure of verifying a hypothesis using measurement results is called a statistical test. Depending on whether the hypotheses about the parameters in the feature distribution are tested or the distribution as a whole is tested, a parametric or non-parametric test is selected. The most significant representatives of parametric tests are the Probability Ratio Test, the Neumann - Pearson Lemma and the Bootstrap method, while the Pearson x2 test and the Kolmogorov test are presented as representatives of nonparametric tests. The paper presents the theoretical basis of some methods used in construction of statistical tests with given examples in geodesy.

Introduction/Objective. Thrombosis of hemodialysis catheters is one of the major complications, which leads to catheter dysfunction. Although tissue plasminogen activator has been proven to be effective in reestablishing blood flow rate through dysfunctional catheters, clinical data in Serbia are missing. The objective of the study was to analyze tissue plasminogen activator efficacy in reestablishing blood flow rate and the influence on catheter survival. Methods. The study included 53 tunneled catheters from 32 patients on hemodialysis. After catheter dysfunction was established, 580,000 units of tissue plasminogen activator was applied into each catheter lumen for about two hours before hemodialysis. The criteria for success was blood flow rate on the next hemodialysis – over 200 mL/minute was considered to be complete success, 180–200 mL/minute partial success, and under 180 mL/minute was considered a failure. Results. Out of 53, 25 catheters (47%) had dysfunction with an incidence of 3.8/1,000 catheter days. Catheters placed in femoral veins, “after-first” catheters, catheters with infection, and catheters in older patients had higher risk for dysfunction. Multivariate logistic regression analysis confirmed that only older age was significantly related to catheter dysfunction. Of the total of 50 applications of tissue plasminogen activator, 35 (70%) were successful, seven procedures (14%) were partially successful and eight (16%) dysfunctional catheters failed to respond to therapy. Six-, 12- and 24-month survival was 87%, 81%, and 20%, respectively, for catheters without dysfunction, and 71%, 47.5%, and 12%, respectively, for catheters with dysfunction. Conclusion. Tissue plasminogen activator dosing is noninvasive, efficient, and safe in reestablishing blood flow rate through dysfunctional catheters, thus prolonging catheters life and sparing patients from additional vascular procedures.

Introduction/objective Autologous transfusion (AT) of blood and/or blood products is more and more commonly used in clinical practice. In ophthalmology, autologous serum (AS) prepared from autologous blood of the patient is commonly used to treat various diseases of the eye, expecially the dry eye syndrome. The objective of the research was to determine the importance of autologous serum implementation in treating eye disease, to establish the implementaion protocol in clinical practice, as well as to analyse the effects of the therapy in patients with various eye conditions. Methodology When prescribed by an ophthalmologist, AS is prepared for a particular patient following a strict preparation protocol. The Clinical Center of Serbia Eye Clinic implements its own modified procedure in preparing AS. From January 1st 2014 until December 31st 2018 540 patients (262-49% men and 278-51% women) have been admitted and treated using AS at the Eye Clinic. Results In 430 (80%)patients, the implementation of AS was initiated during hospitalization, to be continued after discharge and monitored regularly at checkups. In 110 (20%)patients, the AS therapy was initiated at the infirmary to be continued at home after the patient had been adequately educated to implement it correctly. Of all the patients treated with AS, the greatest number suffered from chemical injury of the eye (178 - 33%), a slightly smaller number (148 - 27%) from mechanical injury of the eye and 78 (15%) patients suffered from the dry eye syndrome. The study noted that the first effects of the therapy became evident after two weeks. The effects of the therapy were monitored using objective tests to evaluate the quality of the tear film (Schirmer I test, Rose Bengal test) and by evaluating the precorneal tear film breakup (Tear Break-Up Time - TBUT). The AS therapy can last from a few weeks to a few years. The patients report for check up once a week at the Eye Clinic. Conclusion The AS therapy is a cheap and simple procedure, efficient in treating difficult cases of dry eye syndrome, chemical and thermal eye injury. Preparation and implementation of AS is an activity that must be performed while strictly following rules and standards, which enables the implementation of a standard operative procedure.

Background/Aim. Drug-drug interactions involving antimicrobials present important and often unrecognized complications of pharmacotherapy which can be prevented. The aim of the present study was to identify the frequency and type of potential drug-antimicrobial agent interactions among outpatients and to define recommendations for their management. Methods. Crosssectional prescription database study was conducted. The analysis randomly included 823 patients who visited Health Center Novi Sad over 1-month period (November 1–30, 2011) and had prescribed ≥ 2 drugs where at least one drug was antimicrobial agent for systemic use. All interacting drug combinations involving antimicrobials were identified according to Drug Interaction Facts. Additionally, based on the compendium, potential interactions were classified into categories: pharmacological mechanisms, potential clinical outcomes and management advice. Results. Overall, 88 potential clinically significant drug-antimicrobial agent interactions were identified among 69 (8.4%) exposed outpatients [the mean age 61.7 years (SD ± 15.4); the mean number of prescribed drugs 7.5 (SD ± 2.9); 56.5% females]. The most common identified potential interacting pairs were benzodiazepines undergoing oxidative metabolism and clarithromycin or erythromycin, and aminophylline and ciprofloxacin. In 83.0% of all cases underlying mechanism was pharmacokinetic involving primary inhibition of metabolic pathways mediated by CYP3A4 and CYP1A2 isoenzymes. Excessive sedation (22.7%), cardiotoxicity (20.5%), miscellaneous aminophylline adverse effects (13.6%), and bleeding (10.2%) were the most frequently implicated potential clinical outcomes. Risk for adverse interactions could be managed by close monitoring of simultaneous administration of drugs (37.5%), different risk-modifyng strategies (31.8%), and avoiding combinations (30.7%). Conclusion. Among outpatients, there was common potential for clinically significant interactions involving antimicrobials. Information based on the results of the present study could be integrated in existing computerized physician order entry system in the Health Center as a form of clinical support.

The paper presents the adaptation (fitting) of a set of points, with an estimated two-dimensional positions, to the straight line model of the by the application of the Weighted Total Least Squares, WTLS. The traditional method to solve this problem by using an iterative algorithm of the conditional adjustment with the parameters (Gauss-Helmert's model) is also shown. In the example of testing the straightness of the rail of the crane, a comparison of the efficiency of the two algorithms is performed by means of result of parameter estimation and to the number of required iterations to final solution.

This paper presents geometrically and physically defined height systems, along with their evaluation by the means of Global Navigation Satellite Systems (GNSS) and Global Geopotential Models (GGM). The paper defines ellipsoid heights as an instance of geometrically defined heights; with physically defined heights being represented by definitions of orthometric and normal heights. Methods of normal heights calculation by the means of ellipsoid heights are presented in detail, as determined using the GNSS and height anomalies calculated from the GGM application. Apart from the above, numerical part of the paper evaluates normal height values and compares them to their conditionally accurate values at 1073 points with relatively uniform distribution over the entire territory of Serbia. Conditionally accurate values had been determined by the means of classical geodetic terrestrial methods. Under the procedure of evaluating normal height values, GGM - GGM05C was used, as created in 2016 by the Center for Space Research, University of Texas at Austin. In order to evaluate the quality of applying the model above, data on normal heights evaluation were also presented, using the GGM EGM96, created in 1996 by the National Imagery and Mapping Agency (NIMA), Goddard Space Flight Center (GSFC - NASA) and Ohio State University, presently being the most commonly used model. The comparison above indicates that application of the GGM05C model provides 50 % greater quality of normal heights evaluations against the ones obtained using the EGM96 model. [Projekat Ministarstva nauke Republike Srbije, br. TR 36020]

Introduction. Antibiotic prophylaxis means administration of antibiotics in prevention of infections. Objective. To investigate the efficacy of a single dose preoperative administration of ceftriaxone and cefazolin in the prevention of intra- and postoperative infections in the parturients without high risk of inflammation. Methods. The first group of 45 pregnant and 4 non-pregnant women were preoperatively administered ceftriaxone in a dose of 2 g, i.v., 10 minutes before the planned surgery. The second group of 45 pregnant and 4 non-pregnant women were preoperatively administered cefazolin in a dose of 2 g i.v., 10 minutes before the planned surgery. The concentrations of antibiotics were estimated immediately and 6 hours following the operation, as well as in the amniotic fluid and umbilical cord in the group of pregnant women. The estimation of antibiotic concentration was done by the method of liquid chromatography. Results. The mean concentrations of antibiotics in the patients following the elective caesarean section were as follows: ceftriaxone - 22.7 μg/l. vs cefazolin - 44.8 μg/l. Six hours later, the concentration of antibiotic decreased, but the concentration of cefazolin was still over the MIC for sensitive bacteria. The mean concentrations of antibiotics following gynaecological surgery in the non-pregnant patients were as follows: ceftriaxone - 12.0 μg/l vs cefazolin - 30.1 μg/l. Six hours later, the concentration of antibiotic decreased. Conclusion. It is most optimal to administer a single-dose of the first generation cephalosporins-cefazolin-immediately following the clamping of the umbilical cord as well as in preoperative prophylaxis in gynaecological operations.

Introduction. Hypertension is evident in 80%-85% of patients with chronic renal failure and antihypertensive therapy is needed in 25%-30% of patients. Apart from antihypertensive effect, ACEi’s decrease the left ventricular hypertrophy and mortality in dialysis patients. Even so, their use is limited due to hyperkalemia. Objective. The objective of the study was to compare the effect of fosinopril and enalapril on serum potassium level in hypertensive hemodialysis patients. Method. Prospective pilot study included 16 patients undergoing chronic hemodialysis, with mean age of 58.9±9.6 years and mean duration of hypertension 11.3±7.1 years. The effect of antihypertensive drugs of equivalent dose was followed during three periods (three months each): period 1 (therapy with enalapril), period 2 (therapy with fosinopril) and period 3 (therapy with enalapril). Dialysis conditions were constant and patients were without signs of catabolic state. Laboratory results were followed on monthly basis and mean values were compared by ANOVA-one way test. Difference between variables between periods was tested using Bonferoni method. Results. There was significant difference between mean serum potassium levels throughout three therapeutic periods (5.88±0.38 vs. 4.99±0.44 vs. 5.46±0.46mmol/l; p

This paper describes an artificial immune system approach (AIS) to modeling time-dependent (dynamic, real time) transportation phenomenon characterized by uncertainty. The basic idea behind this research is to develop the Artificial Immune System, which generates a set of antibodies (decisions, control actions) that altogether can successfully cover a wide range of potential situations. The proposed artificial immune system develops antibodies (the best control strategies) for different antigens (different traffic "scenarios"). This task is performed using some of the optimization or heuristics techniques. Then a set of antibodies is combined to create Artificial Immune System. The developed Artificial Immune transportation systems are able to generalize, adapt, and learn based on new knowledge and new information. Applications of the systems are considered for airline yield management, the stochastic vehicle routing, and real-time traffic control at the isolated intersection. The preliminary research results are very promising.