[Show abstract][Hide abstract] ABSTRACT: The aim of the study was to evaluate the adequacy of enzyme-linked immunosorbent assay (ELISA) in the post-exposure determination of the β-agonists clenbuterol and salbutamol in animal plasma and serum. Experimental guinea pigs (n = 20) were treated with two doses (0.25 and 2.5 mg/kg) of clenbuterol (n = 10) and salbutamol (n = 10) for seven days, whereas the control animal group (n = 10) was left untreated. Validation of the applied method yielded acceptable recovery (mean > 70%) and repeatability rates, showing ELISA to be applicable for the semi-quantitative determination of both analytes in both matrices, preferably in plasma. In both matrices, clenbuterol concentrations were proven to be significantly (14-fold) higher than those of salbutamol. Concentrations of both analytes were higher in plasma than in serum. The application of a 10-fold higher clenbuterol and salbutamol dose (2.5 mg/kg) resulted in concentrations 3- to 4-fold higher for clenbuterol and 2- to 3-fold higher for salbutamol, indicating a different release rate of these two β-agonists.
Full-text · Article · Mar 2013 · Journal of analytical toxicology
[Show abstract][Hide abstract] ABSTRACT: The aim of the study was to compare residue depletion of ractopamine HCl as a β-adrenergic agonist that promotes muscle growth of animals, from internal tissues on days after its repeat administration to animals. The experiment was carried out in 38 albino guinea pigs. Treated animals (n = 30) were orally administered ractopamine HCl in a dose of 3.5 mg/kg body mass per day for 7 consecutive days. On days 1, 10, 20 and 30 of drug discontinuation, animals were randomly sacrificed and the liver, kidney, lung, heart, muscle, spleen and fat samples were collected. In all matrices, ractopamine concentration was determined using validated enzyme-linked immunosorbent assay (ELISA) as a quantitative screening method. The highest ractopamine concentration was recorded on day 1 in the lungs (55.80 ± 15.62 μg/kg), followed by the kidney (21.85 ± 3.91 μg/kg), spleen (12.59 ± 1.95 μg/kg), fat (10.17 ± 5.02 μg/kg), heart (9.73 ± 0.22 μg/kg), liver (5.58 ± 2.09 μg/kg), and lowest in muscle (2.21 ± 1.02 μg/kg). Ractopamine residues were detected in the lungs in the period of 30 days after withdrawal in significantly higher concentrations in comparison to other investigated matrices, suggesting that depletion of ractopamine from the lungs occurs at a much slower rate than its depletion from other internal tissues.
Full-text · Article · Jul 2012 · Immunopharmacology and Immunotoxicology
[Show abstract][Hide abstract] ABSTRACT: The anthropogenic impact on the pristine karst lakes was investigated using combination of specific parameters, including multielemental analysis of major inorganic constituents (Al, K, Fe) and trace metals (Li, Ag, Cd, Sn, Pb, Bi, Cr, Co, Ni, Cu, Zn and Sb), polycyclic aromatic hydrocarbons (PAHs) and anionic surfactants of linear alkylbenzene sulfonate (LAS) type. The study was performed in the Plitvice Lakes National Park, situated in a sparsely populated area of the northwestern Dinarides, central Croatia. Dated cores of recent sediments from the two biggest lakes, Lake Prosce and Lake Kozjak, were analysed for the selected contaminants using highly specific methods, involving inductively coupled plasma mass spectrometry (ICP/MS), gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). The concentration of inorganic constituents reflected primarily the geological background of the area as well as geomorphological and geochemical characteristics of the Plitvice Lakes. Due to the higher terrigenous input, the concentration of all elements was significantly higher in the Lake Prosce. The concentration of toxic metals was relatively low in both lakes, except for Cd (>1 mg kg(-1)) and Pb (up to 40 mg kg(-1)). The vertical profiles of these metals suggested that elevated concentrations of Cd were of natural origin, derived from the erosion of the Jurassic dolomite bedrock, while Pb was predominately of recent anthropogenic origin. A similar distribution pattern, suggesting the same prevailing mechanism of input, was observed for pyrolytic PAHs. The characteristic diagnostic PAH ratios revealed that higher PAHs prevailingly originated from the combustion of biomass and fossil fuels. LAS, which represent highly specific indicators of untreated wastewaters, were found in rather high concentrations in the recent sediment layers (up to 4.7 mg kg(-1)), suggesting that contaminated household and hotel wastewaters reach the Lakes, very probably by leaking through the porous karst rocks.
[Show abstract][Hide abstract] ABSTRACT: Picoplankton distribution at the boundary zone of the southern Adriatic in May 2009 on a 75 km long shelf-continental slope transect was assessed by combining epifluorescence microscopy, flow cytometry and high-performance liquid chromatography data with hydrographic observations. The picoplankton distribution was greatly influenced by the hydrographic conditions prevailing in the southern Adriatic because of the influence of the Levantine Intermediate Water (LIW) and East Adriatic Current (EAC) forcing. Heterotrophic bacteria numerically dominated the picoplankton community through the entire transect with no significant accumulation. By contrast, picophytoplankton accumulated in the 50–75 m layer, forming a pronounced deep chlorophyll maximum. Synechococcus dominated the photosynthetic picoplankton, whereas picoeukaryotes were the least abundant. The intrusion of warm LIW observed in the layer between 100 and 350 m was followed by Prochlorococcus and Synechococcus peaks (10 × 103 cells mL−1 and 90 × 103 cells mL−1, respectively), as well as by the appearance of two Synechococcus ecotypes. Most picoeukaryotes were observed at the offshore stations, where geostrophic current calculation revealed the strongest EAC influence. A strong EAC spread over the central and eastern basin created a barrier for Prochlorococcus, whereas the picoeukaryote maxima coincided with the core of the EAC, suggesting its persistence to hydrological instabilities.Research highlights► We examined the influence of hydrographic conditions on picoplankton distribution. ► Picophytoplankton accumulated from 50 to 75 m, forming a deep chlorophyll maximum. ► LIW intrusion was followed by the appearance of two Synechococcus ecotypes. ► The East Adriatic Current (EAC) acted like a barrier for Prochlorococcus. ► The picoeukaryotes maxima coincided with the core of the EAC.
Full-text · Article · Mar 2011 · Estuarine Coastal and Shelf Science
[Show abstract][Hide abstract] ABSTRACT: Counterfeit medicinal products are becoming a significant global issue. It is consideredthat 10% of all medicinal products on the market are counterfeit. The majority of those medicinal products are intended for use in human medicine, though the numbers of those used in veterinary medicine are on the rise. The conscious use of such medicinal products has been equated to a criminal act of threatening life by the European Commission. For that
reason, numerous global organisations working to protect health and suppress crime, and governmental and non-governmental organizations from many countries have becominginvolved in the battle to combat counterfeit medicines. Suppressing the production, distribution and use of counterfeit medicinal products
requires sound and constant cooperation of inspection services, manufacturers and distributors, drug control laboratories and other competent institutions. Cooperation with similar institutions in neighbouring countries and worldwide is also very important, as is the control of medicine quality on the market, and development of a system to inform and educate experts and animal owners. To date, there have been no official reports of counterfeit veterinary medicinal products in the Republic of Croatia, which does not necessarily mean that there are no occurrences within the country.
[Show abstract][Hide abstract] ABSTRACT: The biological activity of tuberculin purified protein derivative (bovine or aviary) on guinea pigs (Cavia porcellus) was investigated after production, prior to the issuance of marketing authorization for this diagnostic means. An experiment on 120 individual guinea pigs was carried out for the purpose of comparing the biological activity of bovine tuberculin PPD from different manufacturers and the analysis of tuberculin just prior to the end of the expiry period, and the analysis of aviary and bovine tuberculin PPD for the purpose of obtaining marketing authorization in the Republic of Croatia. The experiment lasted 85 days and the results indicated that all five batches of tuberculin PPC met the requirements prescribed by the European pharmacopeia and that the obtained results were compliant with experimental results obtained by foreign manufacturers.
[Show abstract][Hide abstract] ABSTRACT: Phytoplankton distribution and environmental characteristics were determined in a shallow, highly stratified and oligotrophic estuary (Zrmanja, eastern Adriatic). Samples were collected in two contrasting seasons; winter (February 2000), when river discharge was high, and in summer (July 2003), a period of drought. Phytoplankton distribution was closely related to salinity gradients, nutrient levels, and water residence time. Microscopic analysis revealed that phytoplankton was composed mainly of marine diatoms, dinoflagellates, cryptophytes, green flagellates, and coccolithophorids. The dominant biomarker pigments were fucoxanthin, alloxanthin and 19'-hexanoyloxyfucoxanthin, while lower, but indicative contributions of peridinin and chlorophyll b were also noted. Maximum abundance and biomass were found in the middle estuary in winter and in the upper estuary in summer. The estuary is mostly P-limited. Development of chain-forming marine diatoms was evident in winter. Due to the reduced nutrient input in summer, the biomass accumulated in the upper estuary (1,000 ng chlorophyll a l(-1)) was composed mostly of nanoplanktonic unicellular diatoms, nanoplanktonic marine dinoflagellates, cryptophytes, and chlorophytes. The concentrations of about 200 ng l(-1) hex-fuco, suggested that the contribution of prymnesiophytes to total biomass was comparable to that of diatoms and dinoflagellates. In the middle estuary and coastal sea, PO(4) and TIN were 3.5 times lower, resulting in a fivefold decrease in biomass (<100 ng chlorophyll a l(-1)). The oligotrophic Zrmanja and other karstic rivers discharging in the eastern Adriatic Sea, provide insufficient source of nutrients and low productivity of the eastern Adriatic Sea.
[Show abstract][Hide abstract] ABSTRACT: Paper reports the results of landfill leachate treatment with membrane bioreactor, nanofiltration and ozonation. Investigated leachate encompasses a number of specific compounds of pharmaceutical origin, including a suite of by-products deriving from the production of vitamin C and propyphenazone. Low biodegradability was observed in MBR (16%) for propyphenazone, while the removal of intermediates from the vitamin C-synthesis was moderate, reaching 30% for diacetone sorbose (DAS) and 69% for diacetone alpha-keto-gulonic acid (DAG). Ozonation almost completely removed propyphenazone but failed to significantly oxidise intermediates from the vitamin C-synthesis. Nanofiltration of the leachate succeeded to remove 99% of DAG and 79% of propyphenazone which made it the most efficient among techniques used.
Preview · Article · Feb 2008 · Water Science & Technology
[Show abstract][Hide abstract] ABSTRACT: The Plitvice Lakes National Park is situated in a pristine and sparsely populated area of the northwestern Dinarides, central Croatia. The basic geomorphological phenomenon of the Park consists of 16 karst lakes interconnected by numerous cascades and waterfalls, formed by travertine barriers. During the last century the area experienced significant changes regarding the prevailing anthropogenic activities, which posed a major challenge for environmental protection and lake conservation. Since the area was proclaimed a national Park in 1949, the traditional economy, based on timber cutting and sawmill activities, was replaced by a fast expanding tourism, accompanied by construction of several hotel capacities along the lakes' shore. In this study, water and sediments were analysed for different organic and inorganic contaminants, using highly specific methods, in order to asses possible impacts of various anthropogenic activities on that protected ecosystem. The concentrations of typical anthropogenic contaminants in the water column of the Plitvice Lakes were generally rather low, which revealed pristine nature of the Lakes. However, some contaminants indicated slightly enhanced levels in the tributaries, which might be indicative of some, still unrecognised, contamination inputs into the Lakes. Moreover, the distribution of contaminants in the recent lake sediments was found to be highly indicative of characteristic historic phases of anthropogenic activities in the area. The most useful indicators of specific contamination sources were aliphatic and aromatic hydrocarbons, surfactants and some toxic metals.
[Show abstract][Hide abstract] ABSTRACT: Phytoplankton distribution and environmen-tal characteristics were determined in a shallow, highly stratified and oligotrophic estuary (Zrmanja, eastern Adriatic). Samples were collected in two contrasting seasons; winter (February 2000), when river discharge was high, and in summer (July 2003), a period of drought. Phytoplankton distribution was closely related to salinity gradients, nutrient levels, and water residence time. Microscopic analysis revealed that phytoplankton was composed mainly of marine diatoms, dinoflagel-lates, cryptophytes, green flagellates, and coccolitho-phorids. The dominant biomarker pigments were fucoxanthin, alloxanthin and 19′-hexanoyloxyfucoxan-thin, while lower, but indicative contributions of peridinin and chlorophyll b were also noted. Maximum abundance and biomass were found in the middle estuary in winter and in the upper estuary in summer. The estuary is mostly P-limited. Development of chain-forming marine diatoms was evident in winter. Due to the reduced nutrient input in summer, the biomass accumulated in the upper estuary (1,000 ng chlorophyll a l −1
Full-text · Article · Jan 2008 · Environmental Monitoring and Assessment
[Show abstract][Hide abstract] ABSTRACT: Background and Purpose: The aim of this study was to evaluate the in vitro influence of mitogens on the lymphoproliferative response after vaccination against classical swine fever (CSF). We also compared the effect of the ORF virus strain D1701, whose immunostimulatory effects in vivo are known, as well as the CSF virus C strain on lymphocyte cell cultures of vaccinated and control pigs.
Material and Methods: Peripheral blood leucocytes (PBL) were used in a lymphocyte proliferation assay by Concanavalin A, phytohemagglutinin, pokeweed mitogen, the attenuated ORF virus strain D1701 and the CSF virus China (C) strain. PBL were obtained from pigs vaccinated with different CSF vaccines (a subunit gp E2 vaccine, a combination of a subunit vaccine and an ORF virus strain D1701 and attenuated C strain vaccine) and from non-vaccinated pigs. Blood samples for the mitogenic response assay were collected before (day 0), and on the 4th, 10th, 21st and 28th post-vaccination day.
Results: PBL of pigs that received the C strain and ORF virus showed in vitro a weaker proliferative response to the mitogens than PBL of pigs vaccinated with the subunit CSF vaccine. The lymphocyte proliferation was observed only in pigs vaccinated with the C strain vaccine after exposure to the same strain in vitro. However, the ORF virus, in the applied concentration did not induce a significant reaction of lymphocytes that originated from either vaccinated or control animals.
Conclusion: The results of our study suggest that the applied mitogens may induce in vitro reactivity which could play a significant immunological role after CSF vaccination. In contrary, the attenuated virus strains used as stimulators, induced no significant lymphoproliferation.
No preview · Article · Apr 2007 · Periodicum Biologorum
[Show abstract][Hide abstract] ABSTRACT: Polyphenolic compounds are widely distributed in the plant kingdom and display a variety of biological activities, including chemoprevention and growth inhibition of tumours. Propolis contains a conglomerate of polyphenolic compounds. We investigated the effect of propolis and polyphenolic compounds, components of propolis, on the growth and metastatic potential of a transplantable mammary carcinoma (MCa) of the mouse. Metastases in the lung were generated by 2 x 10(5) tumour cells injected intravenously (i.v.). A water-soluble derivative of propolis (WSDP) and the polyphenolic compounds (caffeic acid (CA) and caffeic acid phenethyl ester (CAPE)) were given to mice perorally before or after tumour cell inoculation. WSDP, CA and CAPE reduced the number of metastases in the lung. This implies that the antitumour activities of the compounds used in these studies are mostly related to the immunomodulatory properties of the compounds, their cytotoxicity to tumour cells, and their ability to induce apoptosis and/or necrosis.
No preview · Article · Nov 2005 · Veterinary Research Communications
[Show abstract][Hide abstract] ABSTRACT: Propolis contains a variety of polyphenolic compounds. We investigated the effect of a water-soluble derivatives of propolis (WSDP) and polyphenolic compounds, components of propolis, on growth of Ehrlich ascites tumour (EAT) in mice. Tumour in peritoneal cavity was produced by 2×10 EAT cells. WSDP and polyphenolic compounds (caffeic acid-CA, caffeic acid phenethyl ester-CAPE and quercetin-QU) were given to mice perorally (po). It was found that the volume of ascitic fluid induced by EAT cells and total number of cells present in the peritoneal cavity was markedly reduced in EAT-bearing mice treated with test components and the survival time of treated mice was prolonged. Inhibition of EAT growth was due to their effect on the immune system of mice. When innate and acquired immune responses were evaluated, a dose-related increase of cytotoxic T-cell, NK and B cells activity was observed in test components-treated mice. Furthermore, exposure of animals to test components increased functional activity of macrophages to produce factors regulating the function of B-, T-, and NK- cells respectively. In conclusion, these findings imply that the antitumour activity of WSDP and polyphenolic compounds of propolis enhanced host resistance in the EAT tumour model, increasing the activities of macrophages, cytotoxic T cells, B cells and NK cells.
No preview · Article · Sep 2005 · Food and Agricultural Immunology
[Show abstract][Hide abstract] ABSTRACT: Behaviour of anionic surfactants of linear alkylbenzene sulphonates (LAS) type and non-ionic surfactants of nonylphenol polyethoxylate (NPnEO) type was studied in the conventional mechanical/biological sewage treatment plant (STP) as well as using a membrane biological reactor (MBR). LAS and NPnEO were determined using high performance liquid chromatography (HPLC) equipped with spectrofluorimetric detection. Liquid chromatography/tandem mass spectrometry (LC/MS/MS) was used for identification and quantification of stable metabolites, including nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO) and nonylphenoxy carboxylic acids (NPnEC). The study showed that aromatic surfactants belong to the most prominent constituents in the examined municipal wastewaters with typical LAS and NPnEO concentrations of 2-10 mg/L and 0.1-0.5 mg/L, respectively. The removal of aromatic surfactants in conventional STP showed well-known features reported in the literature, including an efficient microbial transformation of the parent molecules and formation of stable metabolic products. The elimination efficiency of aromatic surfactants using the MBR unit was higher than that in the conventional STP, while the composition of recalcitrant nonylphenolic residues in the effluent seems to be ecotoxicologically more favourable due to the lower contributions of the lipophilic metabolites.
No preview · Article · Feb 2005 · Water Science & Technology