Pore geometry of ceramic device: The key factor of drug release kinetics

Release kinetics of tigecycline, a potential antibiotic in treatment of osteomyelitis, from calcium hydroxyapatite (CHA), as one of the most important ceramic materials in bone tissue engineering, was investigated in this study. Tigecycline, in solid state, was mixed with CHA powder and the obtained mixture was compressed into tablets using two different pressures. These tablets were immersed in a phosphate-buffered saline solution and tigecycline release was measured by a UV-VIS spectrophotometer. The total release time was 5 or 28 days, depending on the pressure applied during compression. It was shown that there is a close relationship between pore sizes and drug release rate. The drug release kinetics was interpreted on the base of pore sizes and pore size distribution. [Projekat Ministarstva nauke Republike Srbije, br. 172026

Endometrial immunocompetent cells in proliferative and secretory phase of normal menstrual cycle

Background: Menstruation was presented as a result of inflammatory process. The total and relative numbers of the endometrial immunocompetitive cells vary during the different phases of the menstrual cycle. The aim of this morphological study is to make a contribution to understanding different distribution of leukocyte types during proliferative and secretory phase of normal menstrual cycle. Materials and methods: The study included 40 women (20 in proliferative and 20 in secretory phase of the menstrual cycle). Exploratory curettage performed as preoperative preparation due to uterine myomas. Immunophenotyping was performed by immunoalkaline phosphatase (APAAP) using monoclonal antibodies: CD15, CD20, CD30, CD45RO, CD56, CD57 and CD68. The results were statistically analysed using SPSS 20.0 software. Results: Natural killer (NK) cells are dominant during secretory, and CD45RO T lymphocytes are dominant during proliferative phase of the menstrual cycle. During the secretory phase of menstrual cycle, leukocytes make 30% of total endometrial cells. NK cells (CD56+ bright subpopulation), activated T lymphocytes, macrophages and B lymphocytes significantly increase in their number during the secretory phase of menstrual cycle. Conclusions: Significant changes in endometrial leukocyte populations during proliferative and secretory phase of the menstrual cycle are emphasized. Changes in dominance of different leukocyte subpopulations are determined by hormonal and microenvironmental changes in modulatory factors that have not yet been fully explained

Partial replacement of soybean meal with pumpkin seed cake in lamb diets: Effects on carcass traits, haemato-chemical parameters and fatty acids in meat

The composition of lamb diets has an effect on production traits and meat quality, especially fatty acid proportions. Recently, in organic farming, soybean meal has frequently been replaced with feedstuffs that are rich in protein. The aim of the present study was to determine the effects of partial replacement of soybean meal with pumpkin seed cake on carcass traits, biochemical parameters and fatty acids of lamb meat produced in organic farming. The research was carried out on 70-day-old lambs of the Merinolandschaf breed. Thirty-six lambs were grouped by gender, and allotted to three treatment groups, which were given one of the three diets: control diet with no pumpkin seed cake; a diet in which 10% of soybean meal was replaced with 10% pumpkin seed cake; and a diet in which 15% of soybean meal was replaced with 15% pumpkin seed cake. The experimental feeding period was 30 days. Hay and water were provided ad libitum. Differential blood tests and haematological parameters were determined, and the concentrations of minerals and biochemical parameters, and enzyme activity were ascertained in blood serum. Carcass traits and lamb meat colour did not differ among dietary treatments. Significant differences were observed in the concentrations of some biochemical parameters, which indicated good energy and protein balance, and changes in fat metabolism that did not impair antioxidant status. Compared with the control, the concentration of linoleic acid (C18:2 n-6) was higher in diets containing 10% and 15% of pumpkin seed cake replacements. The results indicated that partial replacement of soybean meal with 10% or 15% of pumpkin seed cake could be implemented in lamb feeding in organic farming without major changes in carcass traits, haemato-chemical parameters and the fatty acid profile in meat.Keywords: Blood parameters, meat quality, Merinolandschaf lambs, organic farmin

"It All Ended in an Unsporting Way": Serbian Football and the Disintegration of Yugoslavia, 1989-2006

Part of a wider examination into football during the collapse of Eastern European Communism between 1989 and 1991, this article studies the interplay between Serbian football and politics during the period of Yugoslavia's demise. Research utilizing interviews with individuals directly involved in the Serbian game, in conjunction with contemporary Yugoslav media sources, indicates that football played an important proactive role in the revival of Serbian nationalism. At the same time the Yugoslav conflict, twinned with a complex transition to a market economy, had disastrous consequences for football throughout the territories of the former Yugoslavia. In the years following the hostilities the Serbian game has suffered decline, major financial hardship and continuing terrace violence, resulting in widespread nostalgia for the pre-conflict era

Efekat deprivacije REM faze spavanja na aktivnost acetilholinesteraze i NA+/K+-ATPaze sinaptozoma mozga pacova u hipotiroidizmu

Hipotireoidizam i deprivacija REM spavanja prepoznati su kao mogući faktori rizika za nastanak neurodegenerativnih oboljenja, pre svega Alchajmerove bolesti (AB). Enzimi acetilholinesteraza (AchE) i Na+ /K+ -ATPaza imaju ulogu u taloženju amiloidnih plakova, tako da je njihova ukupna aktivnost u mozgu obolelog od AB snižena. Cilj istraživanja bio je utvrđivanje mogućeg efekta hipotireoidizma i deprivacije REM faze spavanja na aktivnost AchE i Na+ /K+ -ATPaze. Koristili smo eksperimentalni model hipotireoidizma izazvan propiltiouracilom. Nakon uvođenja u hipotiroidizam, eksperimentalna grupa životinja (n = 12) podeljena je u dve podrupe. Životinje iz prve podgrupe (n = 6) boravile su 72 h na maloj platformi, koja ne dozvoljava REM spavanje, jer usled atonije životinja upada u vodu i budi se. Drugoj podgrupi životinja (n = 6) omogućeno je spavanje. Nakon 72 h, životinje su žrtvovane, i u sinaptozomalnoj frakciji mozga pacova određivana je aktivnost AchE i Na+ /K+ -ATPaze spektrofotometrijski. Rezultati pokazuju da hipotireoidizam dovodi do snižene aktivnosti AchE i Na+ /K+ -ATPaze u odnosu na kontrolu (p ≤ 0,01), dok zajednički efekat hipotireoidizma i deprivacije REM spavanja dovodi do snižene aktivnosti AchE i Na+ /K+ -ATPaze u odnosu na kontrolu (n = 6, p ≤ 0,01), ali ne u odnosu na hipotiroidizam (p > 0,05). Na osnovu dobijenih rezultata možemo zaključiti da hipotireoidizam smanjuje aktivnost enzima AchE i Na+ /K+ -ATPaze, a da deprivacija REM faze spavanja dodatno ne smanjuje aktivnost ovih enzima u hipotireoidizmu, tako je mogući način delovanja hipotireoidizma kao faktora rizika za nastanak AB upravo sniženje aktivnosti ovih enzima.Četvrti srpski kongres o štitastoj žlezdi : Zbornik sažetaka : Septembar, 2017, Zlatibor

Sol-gel as a Method to Tailor the Magnetic Properties of Co1+yAl2-yO4

The magnetic properties of mesoscopic materials are modified by size and surface effects. We present a sol-gel method used to tailor these effects, and illustrate it on Co1+yAl2-yO4 spinel. Nanocomposites made of spinel oxide Co1+yAl2-yO4 particles dispersed in an amorphous SiO2 matrix were synthesized. Samples with various mass fractions -x of Co1+yAl2-yO4 in composite, ranging from predominantly SiO2 (x = 10 wt%) to predominantly spinel (x = 95 wt%), and with various Co concentrations in spinel y were studied. The spinel grain sizes were below 100 nm with a large size distribution, for samples with predominant spinel phase. Those samples showed Curie-Weiss paramagnetic behavior with antiferromagnetically interacting Co ions (theta approximate to -100 K). The grain sizes of spinel stays confined in 100 nm range even in the spinel samples diluted with as low as 5 wt% concentration of amorphous SiO2. For the samples with predominant SiO2 the crystalline nanoparticles are well separated and of size of around 100 nm, but with presence of much smaller spinel nanoparticles of about 10 nm. The magnetic properties of the samples with predominant silica phase showed complex behavior, spin-glass magnetic freezing at the lowest temperatures and lower absolute value of theta and consequently lower exchange constant

Influence of heteropoly acids on rat synaptic plasma membrane atp -ase activity

The in vitro influence of 12-tungstosilicic acid (WSiA) and 12-tungstophosporic acid (WPA) on Na+/K+_ATPase activity, using rat synaptic plasma membrane (SPM) as a model system was investigated. The half-maximum inhibition (IC50) of the enzyme activity was achieved with 5.80⋅ 10-5mol/L of WPA and 1.17⋅10-4 mol/L of WSiA. The both examined compounds showed a dose-dependent inhibitory effect on the enzyme activity in the concentration higher than 1 μmol/L

The possibility of in vitro multi-enzymatic method application for the assessment of the influence of thermal treatments on organic matter digestibility of feed for ruminants

In vitro multi-enzymatic method is a two-step procedure that uses exogenous enzymes for incubation of feed that aim to imitate digestive processes in the animal. It is used for determination of organic matter digestibility (OMD) of various feedstuffs and complete mixtures used in ruminant nutrition. The aim of the present work was to determine whether this in vitro multi-enzymatic method can be applied for the assessment of the influence of thermal treatments on OMD of feed for ruminants. Samples of corn and complete mixture for cows (based on corn) were subjected to pelleting, steam flaking, micronization and extrusion. Statistical analysis of the results did not show significant increase of corn and complete mixture OMD after various thermal treatments compared to untreated samples, which can be explained by high digestibility of corn itself (exceeds 90%). Based on obtained results it can be concluded that applied in vitro method is not suitable for the assessment of the influence of thermal treatments on OMD of corn and corn based mixture, while future research should be broadened to analysis of samples with lower OMD, such as sorghum, oats and barley

Monolacunary Wells-Dawson Polyoxometalate as a Novel Contrast Agent for Computed Tomography: A Comprehensive Study on In Vivo Toxicity and Biodistribution

Polyoxotungstate nanoclusters have recently emerged as promising contrast agents for computed tomography (CT). In order to evaluate their clinical potential, in this study, we evaluated the in vitro CT imaging properties, potential toxic effects in vivo, and tissue distribution of monolacunary Wells–Dawson polyoxometalate, α2-K10P2W17O61.20H2O (mono-WD POM). Mono-WD POM showed superior X-ray attenuation compared to other tungsten-containing nanoclusters (its parent WD-POM and Keggin POM) and the standard iodine-based contrast agent (iohexol). The calculated X-ray attenuation linear slope for mono-WD POM was significantly higher compared to parent WD-POM, Keggin POM, and iohexol (5.97 ± 0.14 vs. 4.84 ± 0.05, 4.55 ± 0.16, and 4.30 ± 0.09, respectively). Acute oral (maximum-administered dose (MAD) = 960 mg/kg) and intravenous administration (1/10, 1/5, and 1/3 MAD) of mono-WD POM did not induce unexpected changes in rats’ general habits or mortality. Results of blood gas analysis, CO-oximetry status, and the levels of electrolytes, glucose, lactate, creatinine, and BUN demonstrated a dose-dependent tendency 14 days after intravenous administration of mono-WD POM. The most significant differences compared to the control were observed for 1/3 MAD, being approximately seventy times higher than the typically used dose (0.015 mmol W/kg) of tungsten-based contrast agents. The highest tungsten deposition was found in the kidney (1/3 MAD—0.67 ± 0.12; 1/5 MAD—0.59 ± 0.07; 1/10 MAD—0.54 ± 0.05), which corresponded to detected morphological irregularities, electrolyte imbalance, and increased BUN levels