FORMULA FOR THE WELL-BEING OF EXPERIMENTAL ANIMALS: 3R + 1R

Animals were first used for research purposes at the beginning of the development of both biology and medicine. However, the expansion in the use of animals for laboratory purposes began in the 19th century. During an experiment, animals may experience fear, deprivation, disease, and various degrees of pain. Animal Protection activists oppose to animal experiments and it is, therefore, necessary to harmonize the worldwide regulations on the use of animals for scientific purposes. More than 50 years ago, Russell and Burch were the first to define the 3R rule. It consists of the following three principles: Replacement, Reduction and Refinement. Over time, one more R was added to stand for Responsibility, meaning a responsible behavior of those who implement the 3R rule. Replacement means that, if possible, each experimental animal model should be replaced by an in vitro method or be reduced to a smaller number of animals used. Reduction is defined as a reduced number of animals used to obtain certain experimental information, while Refinement is a reduction in the frequency or severity of inhumane procedures applied to animals that have yet to be used. The 3R (+1R) rule has its drawbacks, but it is a very important aspect of animal use regulation, which is essential. These rules are used to direct animal users towards an adequate experimental model, but also to be a reminder of the appropriate use of experimental animals at a given time

Određivanje organskih sastojaka mleka kao metoda ocene energetskog statusa mlečnih krava

The objective of the investigations described in this work was to determine the energy status and to make recommendations for correcting the cow diet at a farm of high-yield dairy cows, on the grounds of values for the concentration of organic components of milk and their ratios in individual milk samples. A total of 147 cows were examined, including 97 in the first and 50 in the second lactation. Average concentrations of milk fat and urea were within the physiological values. Namely, the milk fat concentration in cows in the first lactation was 38.88±5.07 g/l, and it was 36.47±4.82 g/l in cows in the second lactation, while the urea concentration in cows in the first lactation 3.16±0.58 mmol/l and it was 3.72±0.64 mmol/l in cows in the second lactation. The protein concentration in both groups of cows was below the physiological values, being 30.33±2.35 g/l in cows in the first lactation and 30.17±2.27 g/l in cows in the second lactation. Based on the ratio of urea and protein concentrations, as well as of fat and proteins in the individual milk samples, it was concluded that in most examined cows, both in those in the first and those in the second lactation, there is a deficit of energy, along with a deficit or relative surplus of proteins. On the grounds of the obtained results, recommendations were given for correcting the feed rations in the coming period. .Cilj istraživanja u ovom radu je bio da se na farmi visokomlečnih krava, na osnovu vrednosti za koncentraciju organskih sastojaka mleka i njihovog odnosa u pojedinačnim uzorcima mleka, utvrdi energetski status i daju preporuke za korekciju ishrane krava. Ukupno je ispitano 147 krava, od kojih je 97 bilo u prvoj, a 50 u drugoj laktaciji. Prosečne koncentracije mlečne masti i ureje bile su unutar fizioloških vrednosti. Naime, koncentracija mlečne masti kod krava u prvoj laktaciji bila je 38,88±5,07 g/l, a kod krava u drugoj laktaciji 36,47±4,82 g/l. Koncentracija ureje kod krava u prvoj laktaciji bila je 3,16±0,58 mmol/l, a kod krava u drugoj laktaciji 3,72±0,64 mmol/l. Koncentracija proteina kod obe grupe krava je bila ispod fiziološke vrednosti, jer je kod krava koje su bile u prvoj laktaciji bila 30,33±2,35 g/l, a kod krava koje su bile u drugoj laktaciji 30,17±2,27 g/l. Na osnovu odnosa koncentracija ureje i proteina, kao i masti i proteina u pojedinačnim uzorcima mleka zaključeno je da kod većine ispitanih krava, kako onih koje su bile u prvoj tako i onih u drugoj laktaciji, postoji deficit energije, uz deficit ili relativni suficit proteina. Na osnovu dobijenih rezultata date su preporuke za korekciju obroka u narednom periodu.

Validation of Atmospheric Boundary Layer Turbulence Model By On-Site Measurements

Modeling atmosperic boundary layer with standard linear models does not sufficiently reproduce wind conditions in complex terrain, especially on leeward sides of terrain slopes More complex models. based on Reynolds averaged Navier-Stokes equations and two-equation kappa-epsilon turbulence models for neutral conditions in atmospheric boundary written in general curvilinear non-orthogonal co-ordinate system, have been evaluated In order to quantify the differences and level of accuracy of different turbulence models, investigation has been performed using standard kappa-epsilon model without additional production terms and kappa-epsilon turbulence models with modified set of model coefficients The sets of full conservation equations are numerically solved by computational fluid dynamics technique. Numerical calculations of turbulence models are compared to the reference experimental data of Askervein hill measurement

FOUR CASES OF APPENDICEAL NEUROMA MIMICKING ACUTE APPENDICITIS

Herein we report four cases of appendiceal neuroma found during a short (one month) monitoring period in patients with severe pain in the lower right abdominal quadrant that underwent appendectomies. Tissue samples were routinely processed to obtain histological sections that were stained with hematoxylin and eosin (H&E) and further with anti-S100 protein antibody. Characteristics of appendiceal neuroma were noted in these cases and they included the absence of mucosal and lymphoid tissue of the appendices, stroma with spindle-shaped cells that were positively stained with anti-S100 protein antibody. This clinical entity is important due to a possible misdiagnosis with acute appendicitis or exacerbation of inflammatory bowel disease and great attention should be paid during the clinical evaluation of similar symptoms.Key words: appendiceal neuroma, misdiagnosis, lumen obliteration, immunohistochemistry, S100 protei

Evidences for lemon-balm essential oil suppression of anxiety-related behavior in animal and in vitro models

Anxiety disorders are among the most frequent psychiatric diseases, with around ¼ of the World population suffering from these disorders during their lifetimes. Besides psyche-related symptoms, these patients can have a large number of somatic symptoms as well. Although the treatment of these disorders is mainly focused on resolving its mental component, one cannot neglect the need for the treatment of accompanying somatic symptoms. Melissa officinalis L. (lemon balm), in various formulations, has been extensively used as an ethnomedicinal remedy for the treatment of different psyche-related symptoms and its use is considered relatively safe. In the present study, the potential activity of M. officinalis essential oil was evaluated in several in vitro models and in vivo animal studies mimicking or involving anxiety-related somatic symptoms. Effects of M. officinalis essential oil on BALB/c mice motor activity was estimated using an open field, rotarod and horizontal wire tests. The performance of mice treated with 25 mg/kg of the oil showed a statistically significant decrease in the motor impairment arising from acute anxiety (open field test), while there was a prolonged latency and a reduction of the frequency of falling from a rotating rod and/or a horizontal wire (signs of muscle weakness/spasms). Additionally, the essential oil was assayed for its potential in inhibiting acetylcholinesterase activity and was found to be a very weak enzyme inhibitor. The potential beneficial properties of the essential oil on the function of the gastrointestinal system were evaluated in the models of spontaneous and induced isolated mouse ileum contractions. Concentrations of the essential oil higher than 1 μg/mL were found to inhibit both spontaneous and induced ileum contractions. The observed activity of the essential oil could be attributed to a large number of different constituents of the oil, most probably the monoterpenes which represent more than 50% of the oil

Volatiles of Pulicaria vulgaris Gaertn. (Asteraceae)

The genus Pulicaria (tribe Inuleae of the Compositae family) consists of ca. 100 species with a distribution from Europe to North Africa and Asia, particularly around the Mediterranean [1]. A number of compounds from Pulicaria species (flavonoids, sesquiterpenoids, and diterpenoids) possess significant bioactivities, and they could be promising candidates for the development of potential drugs [1]. In the continuation of our investigations of the secondary metabolites of plant taxa from the Serbian flora, we have studied the chemical composition of Pulicaria vulgaris Gaertn. essential oil. Pulicaria vulgaris is a rare plant species, with golden-yellow flowers, growing on sandy, stony places. To the best of our knowledge, there are no previous studies on either the volatile or nonvolatile secondary metabolites of this species. Analyses by GC and GC/MS of an essential-oil sample obtained from air-dried aerial parts allowed the identification of 106 components (most of which were identified by at least two independent means (mass spectrum and retention index matching)). Sesquiterpenes constituted the most abundant compound class, representing 86.4% of the total essential oil. The remaining part of the essential-oil sample was comprised of monoterpenes and fatty acid-related compounds, 5.5 and 2.5%, respectively. The bulk of the oil was comprised of two oxygenated sesquiterpenoids–epi-α-cadinol (23.3%) and presilphiperfolane-7,8-diol (46.4%). No plant species other than P. vulgaris are characterized by the presence of presilphiperfolane-7,8-diol. This fact may be of chemotaxonomic/biosynthetic significance since presilphiperfolanes belong to rare triquinane-type sesquiterpenes that represent precursors of angular and propellane triquinane sesquiterpenes

Effects of a combined thymol and carvacrol application on rat kidney damage parameters after L-arginine application

Thymol and carvacrol are two frequently abundant volatile monoterpene phenols found as constituents of different, widely used medicinal plants mainly belonging to the Lamiaceae family. The two compounds were previously proven to possess a large number of pharmacological/toxicological activities, including the nephroprotective activity. The present study aims to evaluate the nephroprotective potential of the two mentioned monoterpenes in L-arginine-induced rat kidney damage model. The potentials of thymol and carvacrol to alleviate kidney impairment were investigated using a different serum (urea, creatinine, sodium, potassium) and homogenate (neutrophil gelatinase-associated lipocalin-NGAL) parameters that reflect kidney tissue damage. Significant rat kidney damage, increased serum urea, creatinine, sodium and potassium levels, as well as NGAL tissue activity, followed the application of L-arginine (3.5 g/kg). Thymol (10 mg/kg), carvacrol (10 mg/kg) or their combination (1:1, w/w, 10 mg/kg) application prior to L-arginine reduced the kidney tissue damage based on the determined values of the previously mentioned parameters. The activity of the combination of the two monoterpenes was found to be more pronounced than the activity of the individual ones at the same total dose. These differences were clearly visible in the urea and potassium serum levels and in the NGAL tissue activity obtained from the corresponding experimental groups. Such greater nephroprotective potential of the combination of the two compounds could be attributed to a possible synergistic effect of the two volatile phenols, since they were proven alone to both possess antioxidant, anti-inflammatory, immunomodulatory, anti-apoptotic, etc. activities

Magneto-dielectric properties of ferrites and ferrite/ferroelectric multiferroic composites

Ni-Zn ferrites, with the general formula Ni1-xZnxFe2O4 (x = 0.0, 0.3, 0.5, 0.7, 1.0), CoFe2O4, BaTiO3 and PbZr0.52Ti0.48O3 powders were synthesized by auto-combustion method. The composites were prepared by mixing the appropriate amounts of individual phases, pressing and conventional sintering. X-ray analysis, for individual phase and composites, indicated the formation of crystallized structure of NiZnFe2O4, BaTiO3 and PbZr0.52Ti0.48O3 without the presence of secondary phases or any impurities. SEM analyses indicated a formation of uniform grain distribution for ferromagnetic and ferroelectric phases and formation of two types of grains, polygonal and rounded, respectively. Magneto-dielectric effect was exhibited in all samples because of the applied stress occurring due to the piezomagnetic effect and the magnetic field induced the variation of the dielectric constant. For all samples the dielectric constant was higher in applied magnetic field. At the low frequency, the dispersion of dielectric losses appeared, while at the higher frequency the value of tan δ become constant (Maxwell-Wagner relaxation). Investigation of J-E relation between leakage and electric field revealed that both nickel zinc ferrite and composites have three different regions of conduction: region with ohmic conduction mechanism, region with the trap-controlled space charge limited current mechanism and region with space charge limited current mechanism

PZT-NICKEL FERRITE AND PZT-COBALT FERRITE COMPARATIVE STUDY: STRUCTURE, DIELECTRIC, FERROELECTRIC AND MAGNETIC PROPERTIES OF COMPOSITE CERAMICS

Multiferroic (MF) materials with simultaneous magnetic and electric long range order and occasionally, mutual magnetoelectric (ME) coupling, have recently attracted considerable interest. These compounds present opportunities for potential applications in information storage, the emerging field of spintronics, sensors, and multistate memory devices [1]. The ME phenomenon is observed in both single- phase as well as composite materials. The challenge in preparing such materials is to find equilibrium ferroelectric and magnetic structures preserving both properties close to the room temperature [2]. The individual phases (Ni0.7Zn0.3Fe2O4, CoFe2O4 and PbZr0.52Ti0.48O3) were prepared by citrate-nitrate combustion reaction method. Composites were prepared by mixing and homogenizing PZT and NZF/CF powders in a planetary ball mill in the ratio: (x) PZT + (1-x) CF/NZF (x = 0.8 and 0.9). XRD diagrams of a sintered composite confirm the presence of only two phases, ferroelectric PZT phase and ferrite phase. SEM analysis revealed a uniform grain arrangement of both phases. Similar values of saturation magnetization (Ms) for both types of composites were observed. Ms increases with increasing magnetic phase, as it was expected. Significantly higher values of coercive field (HC) can be seen in the composite with a cobalt-ferrite, which belongs to the group of hard ferrite unlike NZF which is soft ferrite and characterized by low values of coercive field. The ferroelectric properties of all ceramic composites were also studied

Oregano (Origanum vulgare) essential oil prevents L-arginine-induced rat ileum villi damage

Oregano (Origanum vulgare L., Lamiaceae) is used for centuries as a culinary spice due to its food flavor enhancing properties and its specific aroma. Essential oil isolated from oregano is known to affect the function of the gastrointestinal system by causing stomach and throat smooth muscle relaxation. The present work aims to evaluate the potential protective effects of oregano essential oil in rat ileum intestinal mucosa injury, induced with high doses of L-arginine, by tracking pathological changes in ileum mucosa. Male Wistar rats, divided into four groups (n=6), were treated with 50 mg/kg of oregano essential oil or 200 mg/kg of allopurinol (xanthinoxidase inhibitor) 1 h before a single dose of L-arginine (3.5 g/kg). Two groups served as the controls – one treated with a single dose of L-arginine, while the second group of animals remained untreated. One day after the treatment, all animals were sacrificed and the segments of distal ileum were dissected and fixed in 10% buffered formalin solution. Afterward, the tissue was processed routinely in order to obtain paraffin molds which were further cut into 4-5 µm thin sections and stained with hematoxylin and eosin. Microscopic analysis of the control group ileum revealed short and cylindrical villi, with great resemblance to fingers, with no pathological substrate present. Ileum villi from the group of animals treated only with L-arginine appeared swollen, with the villi tip significantly dilated. Also, in the lamina propria, a large number of leucocytes were visible. The application of both allopurinol and oregano essential oil was able to prevent such significant alterations in the intestinal villi appearance (both in its intensity and frequency) and to reduce the number of leucocytes that migrated to the lamina propria. The detected activity can possibly be attributed to numerous oil constituents found in this essential oil, but predominantly to its major constituents thymol and carvacrol