In vitro effects of ascorbic acid on viability and metabolism of patients’ osteosarcoma stem cells

Stagnation in novelties of osteosarcoma (OS) treatment indicates the need for new therapeutic methods. OS cancer stem cells (OS-CSC) are taught to have the ability to self-renew and develop mechanisms of anticancer drug resistance, and this is why it is difficult to eradicate them. Their metabolism has been recognized as a potential target of therapeutic action. Ascorbic acid (AA) is considered to act pro-oxidative against OS-CSC in vitro by oxidative effect and by inhibition of glycolysis. This study examined an in vitro impact of AA on OS-CSC metabolism isolated from patients\u27 biopsies, with the aim of better understanding of OS-CSC metabolism and the action of AA on OS-CSC. OS-CSC were isolated using a sphere culture system and identified as stem cells using Hoechst 33342 exclusion assay. Determination of the dominant type of metabolism of OS-CSC, parental OS cells, human mesenchymal stem cells (hMSC) and U2OS OS lineage before and after AA treatment was done by Seahorse XF (Agilent). Cytotoxicity of high-dose AA was confirmed by the MTT test and was proven for all the examined cell types as well as HEK293. Seahorse technology showed that OS-CSC can potentially use both glycolysis and oxidative phosphorylation (OXPHOS), and can turn to glycolysis and slow metabolic potential in unfavorable conditions such as incubation in AA

HORSE BREEDING IN THE REPUBLIC OF CROATIA - PRESENT SITUATION AND PERSPECTIVES

Ulaskom Republike Hrvatske u Europsku uniju u posljednjih nekoliko godina implementiraju se prilagodbe koje će osigurati usklađivanje konjogojstva s važećim europskim propisima. Unatoč globalnoj ekonomskoj krizi i u sektoru konjogojstva, ukupan broj konja se u Hrvatskoj kontinuirano povećava i nastavljaju se pozitivni trendovi u uzgoju. No, iako postoji uzlazni trend, posljedice recesije zasigurno će ostaviti traga i na brojnom stanju konja u Hrvatskoj. U posljednjem desetljeću broj konja pod selekcijskim obuhvatom porastao je za više od 72%. Središnji registar kopitara vodi centralnu bazu podataka o kopitarima i broji 49 registra pasmina konja i 28 registra uzgojnih tipova. Centralna baza podataka s prilagođenim programskim sustavom omogućava obvezno elektronsko pohranjivanje podataka koje propisuje Europska unija, a isto se odnosi i na sustav izdavanja Identifikacijskih dokumenata (putovnica). Hrvatska broji ukupno 22.874 registriranih kopitara, od kojih je 20.041 konja. Omjer broja konja pod selekcijskim obuhvatom prema skupinama iznosi za toplokrvnjake 39%, za hladnokrvnjake 56% i za ponije 5%. Državne potpore u uzgoju autohtonih pasmina konja (hrvatski posavac, hrvatski hladnokrvnjak i međimurski konj) te zaštićenih pasmina (lipicanac i magarci) i dalje su aktivne mjere države kroz nacionalni program ruralnog razvoja. Lipicanci, arapski i engleski punokrvnjaci, trakeneri, haflingeri i gidrani uzgojeni u Hrvatskoj su i međunarodno priznate pasmine. Snažnija uzgojna udruženja, kao i državne ergele samostalno provode uzgojne programe i u potpunosti nose uzgojno selekcijski rad pasmina za koje imaju ovlaštenje resornog ministarstva. Uzgoj autohtonih pasmina konja trebao bi davati prednosti ekološkim principima proizvodnje te je potrebno brendiranje, u cilju nacionalne karakterizacije autohtonosti i kvalitete. Konji se koriste u rekreacijske svrhe, ali su nezamjenjivi dio tradicijskih kulturnih manifestacija i kulturne baštine. Intenzivan je trend razvitka svih oblika konjičkog sporta, koji posljedično uvjetuje i povećanje broja grla i poboljšanje njihove kvalitete, kao i korištenje konja za terapijsko jahanje. Perspektiva uzgoja konja u Hrvatskoj temelji se s jedne strane na jačanju kvalitete sportskih konja kao konkurentnog proizvoda za europsko tržište, te s druge strane na brendiranju autohtonih ekoloških proizvoda.Owing to the accession of Croatia to the European Union, adjustments required for the harmonization of horse breeding regulations to the European ones, have been implemented in the last couple of years. Despite global economic crisis, also present in the sector of horse breeding, the total number of horses in Croatia is continuously increasing and positive trends are continuing. In spite of positive trends, consequences of the recession will definitely leave trace in the total number of horses in Croatia. In the last decade the number of horses under selection has increased more than 72%. The Central register of horses runs national horse breeding database and has 49 horse breed registers and 28 breeding type registers. The central database with its software allows saving obligatory data which are regulated by the European law. The program also supports issuing process of Identification documents for ungulates. Croatia has 22,874 registered ungulates with 20,041 horses. The proportion of horse groups under selection is 39% of warmblood horses, 56% of coldblood horses and 5% of ponies. National subsidies in the breeding of autochthonous horse breeds (Croatian Posavac, Croatian coldblood and Medjimurje horse) and protected breeds (Lipizza horses and donkeys) are active state measures in the national program of rural development. Lipizza horses, Pure Arab, Thoroughbred, Haflinger and Gidran horses bred in Croatia are internationally registered breeds. Strong breeding associations and state Stud Farms independently run breeding programs and are carrying out selection programs for breeds authorized by the Ministry of Agriculture. Breeding of autochthonous breeds of horses should prefer ecological production principles which are coming to the market as products where branding is necessary for the goal of national characterization of authenticity and quality. Horses are used for recreational purposes but are also irreplaceable part of traditional cultural manifestations and cultural legacy. Intensive trend of development in all kinds of horse sports is present. It requires the increase in the number of horses and improvement of quality. Using horses for horse therapy is also developing. Perspective in horse breeding in Croatia is based on the one hand in improving horse sport quality as competitive product for the European market, and on other hand on branding of autochthonous ecological products

Preparation of 3D Porous Scaffolds for Bone Tissue Engineering

Inženjerstvo koštanog tkiva brzorastuće je polje istraživanja usmjereno na razvoj bioaktivnih 3D poroznih nosača, kao privremenih izvanstaničnih matrica, koji podržavaju prianjanje, umnažanje i diferencijaciju stanica te potiču stvaranje koštanog tkiva in vivo. Više od deset godina istraživanja naše grupe posvećena su razvoju novih materijala i postupaka za pripravu 3D poroznih nosača za inženjerstvo koštanog tkiva. Kao mogući nosači istraživani su porozni skeleti morskih organizama te kompozitni materijali i hidrogelovi na temelju biorazgradljivih polimera i bioresorbirajuće hidroksiapatitne keramike. U ovom radu dan je prikaz naših istraživanja i glavnih postignuća, objavljenih u međunarodnim znanstvenim publikacijama. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.Bone tissue engineering (BTE) is a fast growing field focused on the development of bioactive 3D porous scaffolds as temporary extracellular matrixes that support cell attachment, proliferation and differentiation, and stimulate bone tissue formation in vivo. Over more than ten years, our group has been devoted to developing new biomaterials and methods to prepare 3D porous scaffolds for BTE applications. The potential of natural porous structures such as marine skeletons, composite materials, and hydrogels based on biodegradable polymers and bioresorbable hydroxyapatite ceramics have been studied. In this paper, an overview of our research and main achievements, published in international scientific publications, is provided. This work is licensed under a Creative Commons Attribution 4.0 International License

EFFECT OF ENVIRONMENTAL TEMPERATURE ON HEARTBEAT OF SHOW JUMPING HORSES DURING TRAINING

Cilj rada bio je prikazati utjecaj temperature okoliša na rad srca 14 konja koji se koriste u preponskom sportu prije, tijekom i nakon treninga. Istraživanja su provedena u privatnom uzgoju na pastusima pasmine Holstein i uzgojnog tipa hrvatskog sportskog konja. Konji su uzgajani i trenirani u istim uvjetima. Mjerenje rada srca provedeno je 60, 30 i 15 minuta te neposredno prije treninga, tijekom i nakon treninga (neposredno nakon, 5, 15, 30, 60, 90, 120 i 180 minuta). Konji su istim intenzitetom bili lonžirani, trenirani na traci za trčanje i skakali prepone u parkuru, u dva ponavljanja, uz nadzor jedne osobe, pri temperaturi od 20 do 25 °C u prvom i od 25 do 30 °C u drugom ponavljanju, a relativnoj vlazi zraka 60-70%. Na temelju dobivenih rezultata istraživanja može se zaključiti da povišene temperature okoline utječu na rad srca tijekom i neposredno nakon treninga. Daljnja istraživanja potrebno je proširiti i na utvrđivanje drugih fizičkih pokazatelja kondicije konja u različitim mikroklimatskim uvjetima.The aim of the study was to determine the effect of environmental temperature on heartbeat of 14 show jumping horses before, during and after training. The research was conducted on a private farm on Holstein stallions, and a breeding type Croatian sports horses. The horses were bred and trained in the same conditions. The measurements of heartbeat were taken before (60, 30 and 15 minutes and immediately before the training), during, as well as after the training (immediately after the training, 5, 15, 30, 60, 90 and 180 minutes). Horses had the same intensity of lunge, running track for horses and hurdle jumping in the parkour in the two repetitions at the temperature of 20-25 °C in the first and 25-30 °C in the second repetition, and relative humidity of 60-70%. Based on the research results it could be concluded that increased environmental temperatures affect the heartbeat of a show jumping horse during and immediately after the training. Further research should also include other physical indicators of horses’ condition under different microclimate conditions

NUTRITIONAL SIGNIFICANCE OF MINERALS IN HORSE FEEDING

Hranidba konja mora biti optimalna, a obroci pravilno izbalansirani, s dovoljnom količinom hranjivih tvari i energije. Minerali su anorganske tvari, prijeko potrebne za sve biološke procese u organizmu pa je konjima nužno osigurati dovoljne količine makro i mikroelemenata u obroku, kao i njihov pravilan međusoban odnos. Potrebe konja za mineralima ovise o pasmini, neurohormonalnom statusu, tjelesnoj masi, kondiciji, dobi, klimatskim prilikama, zdravstvenom stanju, tjelesnoj temperaturi, parazitarnim invazijama, probavnim poremećajima, intenzitetu rada, športskim natjecanjima, forsiranom rastu ždrebadi te stanju organizma, kao što su ždrjebnost ili laktacija. Minerali su nužni aktivni sudionici biokemijskih reakcija koje se događaju u tijelu, a sudjeluju u građi lokomotornoga sustava. Sudjeluju u prijenosu energije, živčanih impulsa i kontrakcije mišića. Nijedan tip obroka ne pruža optimalan omjer mineralnih tvari potrebnih organizmu konja, tako da se svakodnevno u obrocima pojavljuje stanovit manjak ovih biološki aktivnih tvari koje se redovito kompenziraju dodavanjem mineralno-vitaminskih premiksa. Ukoliko dođe do deficita minerala, smanjit će se učinkovitost iskorištavanja energije iz obroka. Kada se pri nestašici minerala u organizmu potroše zalihe, narušeni tijek biokemijskih procesa uvjetuje kliničke i patomorfološke promjene. Hranom primljene prekomjerne količine minerala u organizmu stvaraju zalihe te može doći do pojave simptoma trovanja zbog toga što se nagomilavanjem minerala u pojedine organe narušava tok određenih biokemijskih reakcija. Odgovarajući način hranidbe, uz djelovanje nasljedne osnove te pravilan trening, omogućit će maksimalno iskorištavanje potencijala konja. Sastavljanje pravilnoga obroka, s obzirom na zahtjeve konja, predstavlja velik izazov.Horse feeding must be optimal, and meals properly balanced with the sufficient amount of nutritious substances and energy. Minerals are inorganic substances which are necessary for all biological processes in an organism. It should be ensured that horses get sufficient amounts of balanced macroelements and microelements in a meal. The horse’s need for minerals depends on the breed, neurohormone status, body weight, fitness, age, climate change, health, body temperature, parasites occurrence, digestive disorders, labour intensity, sports competitions, forced growth of foals and the state of organism, such as foaling condition or lactation. Minerals are essential active participants in biochemical reactions which occur in the body, and participate in the anatomy of locomotor system. They also participate in transmission of energy, nervous impulses and muscle contractions. There is not one kind of meal that offers an optimal range of mineral substances necessary for the horse’s organism, so there is a lack of these biologically active substances in every meal, which is regularly compensated by adding mineral-vitamin mixtures. In case of mineral deficits, the efficiency of obtaining energy from rations will be reduced. When mineral supplies are low due to the lack of minerals in an organism, the disturbed biochemical processes cause clinical and patomorphological changes. An excessive intake of minerals creates supplies in an organism, thus causing poisoning because of disruption of some biochemical reactions. Adequate feeding, inheritance base and proper training enable maximum use of horse’s potentials. Preparing a proper meal, regarding horse’s needs, presents a great challenge

Multiphase zinc and magnesium mono-substituted calcium phosphates derived from cuttlefish bone : A multifunctional biomaterials

Biomimetic calcium phosphate (CaP) systems mono-substituted with zinc (Zn2+) and magnesium (Mg2+) ions were prepared from a biogenic source (cuttlefish bone) by wet precipitation method. The results revealed that the as-prepared powders were composed of calcium-deficient carbonated hydroxyapatite (HAp), octacalcium phosphate (OCP), and amorphous calcium phosphate (ACP), while the heat-treated powders consisted of HAp, α-tricalcium phosphate (α-TCP), and β-tricalcium phosphate (β-TCP). In addition to Zn2+ and Mg2+ ions, the presence of CO32−, Sr2+ and Na + ions was detected with elemental analysis, which can be attributed to the use of cuttlefish bone as a natural precursor of Ca2+ ions. The data obtained by XRD study demonstrated the decrease in lattice parameters in the OCP and β-TCP phases for Zn-substitution and Mg-substitution in the HAp, OCP, and β-TCP phases. Zn2+ occupies the Ca(1,3,4,6,7,8) sites in OCP and Ca(1,2,3,4) sites in β-TCP, while Mg2+ occupies the Ca(2) sites in HAp and the Ca(4,5) sites in β-TCP. Phase transformation study under simulated physiological conditions for 7 days showed the transformation of OCP and ACP into the thermodynamically more stable HAp. Characterization of the zeta-potential showed positively charged populations for all prepared CaP powders, while all samples showed high bovine serum albumin adsorption capacity. The culture of human embryonic kidney cells showed that the prepared CaPs are non-cytotoxic and that viability of the cells increases during the culture period. All powders obtained showed antibacterial activity towards Gram-negative Escherichia coli and low antibacterial effect against Gram-positive Staphylococcus aureus, as determined by viability analysis during 48 h. Inhibition zone analysis and observation of the morphology after 24 h showed no antibacterial properties.publishedVersionPeer reviewe

Uticaj dekabromovanog difenil etra na toksičnost kadmijuma posredstvom oksidativnog stresa - subakutna oralna studija na pacovima

It is known that kidneys are target tissue for Cd toxicity but there is not enough literature data on kidney effects of BDE-209. Moreover, Cd as toxic metal and BDE-209 as organic halogenated pollutant can share similar mechanism of action like, oxidative stress which is already assumed. However, how will Cd act as prooxidant in presence of BDE-209 is still not investigated, therefore, the objective of this study was to assess this BDE-209 influence. Results of this study indicated slight decrease in MDA in rat's kidney homogenates after subacute exposure to Cd and/or BDE-209, while SOD activity was increased and content of -SH groups decreased. Based on dose-response assessment, BDE-209 did not influence Cd toxicity mediated by chosen oxidative stress parameters, namely the derived CEDL5 values were the same for single Cd and for Cd given in combination with the BDE-209. In conclusion, dynamic of oxidative process has influence on the parameters levels. Co-exposure with polybrominated organic pollutant did not influence Cd effects on oxidative stress parameters. Having in mind that this is pilot study, performed with only one dose of BDE-209, further investigations are necessary, including changes in dose ranges, duration of exposure etc. Moreover, results contributes to the issue of mixture toxicology even BDE-209 did not influenced oxidative stress as mechanism of Cd toxicity.Poznato je da su bubrezi ciljni organ toksičnosti kadmijuma, ali je mnogo manje literaturnih podataka o toksičnim efektima BDE-209 na bubrege. Kadmijum, kao toksičan metal i BDE-209, kao organska halogenovana zagađujuća supstanca mogu imati sličan mehanizam dejstva posredovan oksidativnim stresom. Međutim, kako će Cd da deluje kao prooksidant u prisustvu BDE-209 još uvek nije proučavano, te je cilj ovog rada bio da se proceni uticaj BDE-209 na oksidativni stres posredovan kadmijumom. Rezultati ovog istraživanja ukazuju na blagi pad koncentracije MDA u homogenatima bubrega pacova nakon subakutne ekspozicije Cd i/ili BDE-209, dok se aktivnost SOD povećava i sadržaj - SH grupa smanjuje. Na osnovu procene odnosa doza-odgovor, BDE-209 nije imao uticaja na toksičnost Cd izazvanu posredstvom oksidativnog stresa (posmatrajući odabrane parametre). Potvrda je dobijena i iz izračunatih donjih granica pouzdanosti doze od 5% - CEDL5 jer su vrednosti su bile iste za sam Cd i Cd primenjen u kombinaciji sa BDE-209. Može se zaključiti da dinamika oksidativnih procesa ima uticaj na vrednosti parametara oksidativnog stresa, da stoga istovremena ekspozicija Cd i polibromovanom organskom polutantu nije promenila uticaj samog Cd na parametre oksidativnog stresa. Imajući u vidu da je ovo pilot studija, izvršena sa samo jednom dozom BDE-209, potrebna su dalja istraživanja, uključujući i promene opsega doza, trajanje ekspozicije itd. Pored toga, rezultati ove studije doprinose tumačenju toksikologija smeša, iako BDE-209 nije imao uticaja na oksidativni stres kao mehanizam Cd toksičnosti za date uslove ekspozicije

Faktori koji utiču na cenu antibiotske terapije i ishod kod kritično obolelih pacijenata - 'real-life' studija

Background/Aim. Critically ill patients are at very high risk of developing severe infections in intensive care units (ICUs). Procalcitonin (PCT) levels are eleveted in the circulation in patients with bacterial sepsis and PCT might be useful in guiding antibiotic treatment. The aim of this study was to estimate factors influencing patients survival and treatment cost in ICU with special emphasis on the impact of PCT serum levels use in guiding antimicrobial therapy. Methods. The study was conducted from August 2010 to May 2012 in the Intensive Therapy Unit, Clinic of Anesthesiology and Intensive Therapy, Military Medical Academy (MMA), Belgrade, Serbia. All adult critically ill patients with sepsis and/or trauma admitted in the ICU were included in the study. This study included only the cost of antimicrobial therapy in the ICU and the cost for PCT analysis. We used prices valid in the MMA for the year 2012. PCT in serum was measured by homogeneous immunoassay on a Brahms Kryptor analyzer. Results. A total of 102 patients were enrolled. The mean patients age was 55 ± 19 years and 61.8% of patients were male. The mean length of stay (LOS) in the ICU was 12 ± 21 days. There was a statistically significant difference (p lt 0.001) between the sepsis and trauma group regarding outcome (higher mortality rate was in the sepsis group, particularly in the patients with peritonitis who were mostly women). The patients younger than 70 years had better chance of survival. LOS, the use of carbapenems and PCT-measurement influenced the cost of therapy in the ICU. Conclusions. The obtained results show that age, the diagnosis and gender were the main predictors of survival of critically ill patients in the ICU. The cost of ICU stay was dependent on LOS, use of carbapenems and PCT measurement although the influence of these three factors on the outcome in the patients did not reach a statistical significance.Uvod/Cilj. Kritično oboleli pacijenti imaju veliki rizik od razvoja teških infekcija u jedinicama intenzivne terapije (JIT). Nivo prokalcitonina (PCT) u cirkulaciji je povišen kod bolesnika sa bakterijskom sepsom, tako da PCT može biti koristan u praćenju antibiotske terapije. Cilj ove studije bio je da se ustanove faktori koji utiču na ishod i troškove lečenja u JIT u našoj ustanovi sa posebnim naglaskom na uticaj korišćenja serumskog nivoa PCT u vođenju antimikrobne terapije. Metode. Studija je sprovedena od avgusta 2010. godine do maja 2012. godine u Jedinici intenzivne terapije Klinike za anesteziologiju i intenzivnu terapiju Vojnomedicinske akademije (VMA) u Beogradu, Srbija. Svi kritično oboleli sa sepsom i/ili traumom koji su primljeni u JIT bili su uključeni u studiju. Studijom su obuhvaćeni samo troškovi antimikrobne terapije u JIT i troškovi PCT analize. Koristili smo cenovnik VMA za 2012. godinu. PCT u serumu je meren tehnikom homogenog imunoeseja na Brams Kriptor analizatoru. Rezultati. Studijom su bila obuhvaćena 102 bolesnika. Prosečna starost bolesnika iznosila je 55 ± 19 godina, a 61,8% bolesnika bili su muškarci. Prosečna dužina boravka u JIT (lenght of stay LOS) iznosila je 12 ± 21 dana. Postojala je statistički značajna razlika (p lt 0.001) između ishoda lečenja u grupi sa sepsom u odnosu na grupu sa traumom. Bolesnici mlađi od 70 godina imali su bolju šansu da prežive. Dužina boravka, upotreba karbapenema i merenje PCT uticali su na cenu terapije u JIT. Zaključak. Dobijeni rezultati pokazuju da su godine života, dijagnoza i pol bili glavni prediktori preživljavanja kritično obolelih u JIT. Cena terapije zavisila je od dužine boravka u JIT, upotrebe karbapenema i merenja PCT, ali uticaj ovih faktora na ishod lečenja nije dostigao statističku značajnost