Profilaxis, immunoprophylaxis and therapy of staphylococcal mastitis

Inflammation of the mammary gland, mastitis, in cows presents one of the most acute problems in intensive milk production, incurring huge economic losses which reach from 20-80% even in developed countries in the past decade. On the grounds of the programme of the respective Ministry, the Veterinary Service of the Republic of Serbia is obliged to monitor, detect, curb and control infective inflammation of the mammary gland caused by staphylococcus and streptococcus. Long-term different approaches to mastitis treatment did not result in the required solution, so that the problem of mastitis is still present and acute. In order to prevent the infiltration of the pathogenic cause into the mammary gland, its populating and multiplication, it is necessary to maintain constant and regular controls of milk, as well as undertake of preventive and therapeutic measures aimed at reducing the incidence of mastitis. Immunization and immunotherapy of mastitis are new and very interesting areas for scientific investigations and work. In the recent decades vaccines against staphylococcal mastitis are being successfully developed, whose success is reflected in the reduced incidence of clinical and subcilinical mastitis

Electrochemical Removal of Microorganisms in Drinking Water

It is known that silver, even in small concentrations (hundred parts of milligrams per liter), has the ability to destroy microorganisms, i.e. it has strong bactericidal abilities. Cleansing vast amount of water using bactericidal ability of silver is usually performed in electrochemical way. The advantages of electrochemical disinfection process like: (a) environmental compatibility, (b) versatility to kill a wide variety of microorganisms under mild conditions, (c) no need for adding chemical medicines and (d) the benefits of in-situ generation greatly lower problems and dangers of usage gas chlorine in water disinfection, which is greatest during transport and storing of this disinfectant. Appliances for electrochemical disinfection of drinking water eliminate these faults of conventional disinfection methods. Medical researches show that excess of chlorine in water reacts with organic matter, leading to mutations and cancer formation in digestion organs and bladder. This paper represents research of succesful microbiological disinfection of natural water that contains Acinetobacter, Pseudomonas aeruginisa, Sulfate-reducing clostridium, Streptococcus (F), Aeromonas, Citrobacter (F), Esherichia coli, Enterobacter (F) and Bacillus by water-disinfection appliance. This appliance can be used in water systems like water sorces, traps, reservoires, pools etc. (certificate of Clinical Center of Serbia)

The role of bile acids in epigenetic regulation of oxidative stress and apoptosis in normal and malignant cells

Žučne kiseline deluju kao signalni molekuli u organizmu i uključene su u regulaciju brojnih metaboličkih, inflamatornih i imunomodulatornih procesa. Ova endogena jedinjenja ostvaruju svoje efekte najvećim delom putem nuklearnih receptora. Farnezoid X receptor (FXR) je glavni regulator homeostaze žučnih kiselina, a pokazano je da je značajno uključen i u procese inflamacije i kancerogeneze, prevashodno u jetri i intestinalnom traktu. Aktivacija FXR receptora predstavlja značajnu farmakološku strategiju za terapiju holestatskih bolesti jetre, inflamatorne bolesti creva i karcinoma kolona. Definisana je uloga žučnih kiselina u signalnim putevima koji regulišu ćelijski ciklus i doprinose razvoju ili regresiji maligniteta, ali je malo poznat uticaj ovih jedinjenja na epigenetske mehanizme regulacije ključnih ćelijskih procesa. Imajući u vidu da su efekti žučnih kiselina determinisani njihovom polarnošću, cilj istraživanja je bio da se ispita uticaj sintetski dobijenog keto derivata holne kiseline, 12-monoketoholne kiseline (MKH), u komparaciji sa prirodnim žučnim kiselinama, hidrofobnom henodeoksiholnom kiselinom (HDH) i hidrofilnom ursodeoksiholnom kiselinom (UDH), na ćelijske procese apoptoze, oksidativnog stresa i inflamacije, koji su od značaja za hemoprevenciju i terapiju karcinoma kolona, u in vitro i in vivo sistemima. Cilj istraživanja je takođe obuhvatao i ispitivanje uloge odabranih žučnih kiselina u epigenetskoj regulaciji ovih procesa u ćelijama karcinoma kolona. Na in vivo modelu intrahepatične holestaze kod eksperimentalnih životinja, pokazano je da UDH i MKH ispoljavaju antiapoptotski, antioksidativni i antiinflamatorni efekat u jetri i intestinumu. Utvrđeno je da UDH i MKH sprečavaju mitohondrijalni put aktivacije apoptoze u jetri, dok UDH ispoljava antiapoptotski efekat i u intestinumu eksperimentalnih životinja sa holestazom. Ove dve žučne kiseline su u značajnoj meri modulirale ekspresiju gena uključenih u antioksidativnu zaštitu, kao i aktivnost antioksidativnih enzima, u jetri i intestinumu eksperimentalnih životinja sa holestazom, ka nivoima ekspresije i aktivnosti kod zdravih, netretiranih životinja. Dok su UDH i MKH u dozi od 4 mg/kg ispoljile antiinflamatorno dejstvo u jetri i intestinumu smanjenjem ekspresije gena za proinflamatorni transkripcioni faktor NF-κB, primena HDH i MKH u dozi od 20 mg/kg je imala suprotan efekat. Na modelu HT-29 ćelijske linije adenokarcinoma kolona, utvrđeno je da polusintetska žučna kiselina MKH ispoljava značajno manju citotoksičnost u odnosu na HDH i nešto veću citotoksičnost u odnosu na UDH. Epigenetski lek vorinostat je ispoljio sinergističko citotoksično dejstvo sa sve tri ispitivane žučne kiseline. Vorinostat je ostvario proapoptotski i antiproliferativni efekat u HT-29 ćelijama, koji je bio najizraženiji u kombinaciji sa MKH, s obzirom da je došlo do značajnog povećanja odnosa ekspresije BAX i BCL2 gena i smanjenja ekspresije gena za marker proliferacije ciklin D1. Vorinostat je, takođe, značajno smanjio antioksidativni kapacitet HT-29 ćelija smanjenjem ekspresije NRF2 gena i sledstvenim smanjenjem ekspresije gena za antioksidativne enzime. HDH je dodatno smanjila, a MKH poboljšala antioksidativni kapacitet HT-29 ćelija modulacijom ekspresije NRF2 gena. U in vitro i in vivo sistemu u okviru ove doktorske disertacije je pokazano da, pored HDH kao poznatog endogenog agoniste FXR receptora, MKH takođe povećava ekspresiju gena za FXR i njegovog ciljnog gena za transkripcioni korepresor SHP, što ukazuje da ova polusintetska žučna kiselina može da aktivira FXR. Osim toga, utvrđeno je da žučne kiseline ispoljavaju različite efekte prema ekspresiji gena za histon deacetilaze HDAC1 i HDAC2 u jetri i intestinumu eksperimentalnih životinja, kao i u HT-29 ćelijama karcinoma kolona, a jedino je UDH značajno smanjila ekspresiju gena za oba ispitivana enzima uključena u epigenetsku regulaciju ćelijskih procesa, i u isptivanim tkivima i HT-29 ćelijama. Rezultati našeg rada ukazuju da bi se UDH i MKH mogle koristiti u hemoprevenciji karcinoma kolona u niskim dozama, s obzirom na utvrđene efekte u modulaciji ekspresije gena uključenih u procese apoptoze, oksidativnog stresa i inflamacije. Takođe, s obzirom na ostvaren sinergistički efekat žučnih kiselina sa epigenetskim antitumorskim agensom vorinostatom, otvara se mogućnost kombinovane farmakološke strategije u terapiji solidnih tumora, koji u najvećem procentu pokazuju rezistenciju prema samom vorinostatu.Bile acids act as signaling molecules in the organism and they are involved in the regulation of numerous metabolic, inflammatory and immunomodulatory processes. These endogenous compounds exert their effects mostly by binding and activation of nuclear receptors. Farnesoid X receptor (FXR) is the main regulator of bile acid homeostasis, and has been shown to be significantly involved in processes of inflammation and carcinogenesis, primarily in the liver and intestinal tract. Activation of FXR receptor represents a significant pharmacological strategy for the treatment of cholestatic liver disease, inflammatory bowel disease, and colon carcinoma. The role of bile acids in signaling pathways regulating the cell cycle and contributing to the development or regression of malignancies is well determined, but the effects of these compounds on epigenetic mechanisms of key cellular processes regulation is yet to be elucidated. Given that the effects of bile acids are mostly determined by their polarity, the aim of our study was to investigate in vitro and in vivo effects of semi-synthetic keto derivative of cholic acid, 12-monoketocholic acid (MKC), in comparison to natural bile acids, hydrophobic chenodeoxycholic acid (CDC) and hydrophilic ursodeoxycholic acid (UDC), on processes of apoptosis, oxidative stress and inflammation, which are significant for both  chemoprevention and therapy of colon cancer. Besides, the aim of our study was to examine the role of selected bile acids in the epigenetic regulation of these processes in colon cancer cells. In in vivo model of intrahepatic cholestasis in experimental animals, it has been demonstrated that UDC and MKC exhibit antiapoptotic, antioxidant, and antiinflammatory effects in the liver and intestine. It was shown that UDC and MKC prevent the mitochondrial pathway of apoptosis activation in the liver, while UDC exhibits an antiapoptotic effect in the intestine of experimental animals with cholestasis as well. These two bile acids significantly modulated the expression of genes involved in antioxidant protection, as well as the activity of antioxidant enzymes, in the liver and intestine of experimental animals with cholestasis, towards levels of expression and activity in healthy, untreated animals. While UDC and MKC at a low dose of 4 mg/kg exhibited an antiinflammatory effect in the liver and intestine by reducing the expression of the gene encoding the proinflammatory transcription factor NF-κB, the application of CDC and MKC at a high dose of 20 mg/kg exerted the opposite effect. In HT-29 human adenocarcinoma cell line, it has been demonstrated that semi-synthetic bile acid MKC exhibits significantly lower cytotoxicity than CDC and slightly higher cytotoxicity than UDC. The epigenetic drug vorinostat has exhibited a synergistic cytotoxic effect with all three investigated bile acids. Vorinostat exerted proapoptotic and antiproliferative effects in HT-29 cells, which were most pronounced in combination with MKC, as there was a significant increase in the ratio of BAX and BCL2 genes expression and a decrease of the proliferation marker cyclin D1 gene expression. Vorinostat also significantly reduced the antioxidant capacity of HT-29 cells by reducing the expression of NRF2 gene and consequently decreasing the expression of genes encoding antioxidant enzymes. CDC further reduced, while MKC improved the antioxidant capacity of HT-29 cells by modulating the expression of NRF2 gene. In both in vitro and in vivo systems, it was demonstrated that, in addition to CDC as a known endogenous FXR agonist, MKC also increased the expression of the gene encoding FXR, and FXR target gene encoding transcriptional co-repressor SHP as well, indicating that this semi-synthetic bile acid can also activate FXR. Besides, bile acids have been shown to exert distinct effects on the expression of the histone deacetylases HDAC1 and HDAC2 gene in the liver and intestine of experimental animals, and in HT-29 colon cancer cells. Only UDC significantly reduced the expression of the genes for both studied enzymes involved in the epigenetic regulation of cell processes, in both tissues and HT-29 cells. The results of our work indicate that UDC and MKC could be used in chemoprevention of colon cancer at low doses, considering determined effects in the modulation of expression of the genes involved in processes of apoptosis, oxidative stress and inflammation. Furthermore, synergistic effects of bile acids with the epigenetic antitumor agent vorinostat open up the possibility of a combined pharmacological strategy in the treatment of solid tumors, which are at the high percentage resistant to the effects of vorinostat alone

Novi metod određivanja specifične površine elektrohemijski istaloženog bakra

The specific surface of electrodeposited copper was determined using recently proposed way for the estimation of the real surface area of metal deposits. The obtained values of the specific surface of copper deposits were correlated with the corresponding morphologies of copper deposits.Specifična površina elektrohemijski istaloženog taloga bakra je bila određena korišćenjem nedavno predloženim načinom za procenu realne površine taloga metala. Dobijene vrednosti specifične površine taloga bakra su bile povezane sa odgovarajućim morfologijama taloga bakra

Structural and Electrical Properties of Sintered Zinc-titanate Ceramics

Poster presented at the ELECTROCERAMICS X, June 18-22, 2006, Toledo, Spai

Effect of parameters of pulsating current (PC) regimes on morphology of electrodeposited copper in hydrogen co-deposition range

The most often employed electrolytes for the electrodeposition of copper are those based on aqueous solutions of sulfuric acid (H2SO4) and cupric sulfate (CuSO4). There is an ionic equilibrium of a lot of species in the CuSO4-H2SO4-H2O system. Electrodeposition processes at high current densities and overpotentials are very suitable for experimental verification of this ionic equilibrium, because there is parallelism between copper electrodeposition and hydrogen evolution reaction at high current densities and overpotentials. In this study, it is shown that effects attained by the choice of appropriate parameters of square-waves pulsating current (PC) on morphology of electrodeposited copper were equivalent to those obtained by electrodepositions at the constant overpotential in the hydrogen co-deposition range from six solutions of different concentrations of CuSO4 and H2SO4. In this way, it was clear that it is possible to simulate the ionic equilibrium of the species in the CuSO4-H2SO4-H2O system using the only one electroplating solution if the appropriate parameters of PC regimes are used.Belgrade, Serbia, June 6-10, 201

Effect of the electrolysis regime on the structural characteristics of honeycomb-like electrodes

The effect of different current regimes of electrolysis on the micro- and nanostructural characteristics of open porous structures was examined by the analysis of honeycomb-like copper electrodes obtained by constant galvanostatic (DC) electrodeposition and by regimes of pulsating (PC) and reversing (RC) current. An increase in the number of holes fowled by detached hydrogen bubbles, the decrease in wall width between holes and changes in surface morphology around holes from cauliflower-like agglomerates of copper grains to dendrites were observed in the following order: the DC, PC and RC regime. The hole size formed in the RC regime was smaller than the hole size formed in the DC and PC regimes. Analysis of the obtained structural characteristics showed that the specific surface area of the honeycomb-like electrodes was increased by the application of the PC and RC regimes in relation to the DC regime

Effect of parameters of pulsating current (PC) regimes on morphology of electrodeposited copper in hydrogen co-deposition range

The most often employed electrolytes for the electrodeposition of copper are those based on aqueous solutions of sulfuric acid (H2SO4) and cupric sulfate (CuSO4). There is an ionic equilibrium of a lot of species in the CuSO4-H2SO4-H2O system. Electrodeposition processes at high current densities and overpotentials are very suitable for experimental verification of this ionic equilibrium, because there is parallelism between copper electrodeposition and hydrogen evolution reaction at high current densities and overpotentials. In this study, it is shown that effects attained by the choice of appropriate parameters of square-waves pulsating current (PC) on morphology of electrodeposited copper were equivalent to those obtained by electrodepositions at the constant overpotential in the hydrogen co-deposition range from six solutions of different concentrations of CuSO4 and H2SO4. In this way, it was clear that it is possible to simulate the ionic equilibrium of the species in the CuSO4-H2SO4-H2O system using the only one electroplating solution if the appropriate parameters of PC regimes are used.Belgrade, Serbia, June 6-10, 201

Electrodeposition of iron powder particles of different characteristics

Iron deposits obtained at high current densities and overpotentials are very important from a technological point of view. It has been stated that the open and porous structures of copper or iron deposits obtained at high current densities were ideally suited for use as electrodes in electrochemical devices such as fuel cells, batteries and chemical sensors, while the extremely high surface area is relevant for evaluating some electrochemical reactions. Mainly two types of electrolytes were investigated and these were based on sulfate and chloride electrolytes. With increasing duration of electrolysis, dendrites merge, which is unacceptable for the case of further application. These deposits must be grinded in order to obtain powders. However, in the range of lower acidity the deposits become powdery and, in some cases, may be spongy and sticky. Generally, up to now research indicates that electrodeposition of Fe powders have two steps, deposition of fragile film and grinding. It must be emphasized that we tried and succeeded to obtain Fe powders without grinding process. The aim of this work was to investigate electrodeposition processes of Fe powders from sulfate and chloride electrolytes and morphologies of powder as a function of type of electrolyte and current density.Belgrade, Serbia, June 6-10, 201

Electrodeposition of iron powder particles of different characteristics

Iron deposits obtained at high current densities and overpotentials are very important from a technological point of view. It has been stated that the open and porous structures of copper or iron deposits obtained at high current densities were ideally suited for use as electrodes in electrochemical devices such as fuel cells, batteries and chemical sensors, while the extremely high surface area is relevant for evaluating some electrochemical reactions. Mainly two types of electrolytes were investigated and these were based on sulfate and chloride electrolytes. With increasing duration of electrolysis, dendrites merge, which is unacceptable for the case of further application. These deposits must be grinded in order to obtain powders. However, in the range of lower acidity the deposits become powdery and, in some cases, may be spongy and sticky. Generally, up to now research indicates that electrodeposition of Fe powders have two steps, deposition of fragile film and grinding. It must be emphasized that we tried and succeeded to obtain Fe powders without grinding process. The aim of this work was to investigate electrodeposition processes of Fe powders from sulfate and chloride electrolytes and morphologies of powder as a function of type of electrolyte and current density.Belgrade, Serbia, June 6-10, 201