ABSTRACT
Data, despite being crucial for internal dose assessment, is lacking on the transfer of artificial radionuclides from the environment to the food supply. Expanding the available information on these factors is important for the improvement of dose models for specific scenarios. This paper describes the results of a 70 day field experiment with broiler chickens on the dynamics of excretion of 137Cs and 241Am from the muscle, liver and bone of broilers after a 30 day application of contaminated feed. The radionuclide concentrations in the feed and the thigh muscle, thigh bone and liver of 54 chickens divided between grass meal and soil contaminated feed groups were evaluated by gamma spectrometry for 241Am and 137Cs. The obtained results confirm previous data on the dynamics of the excretion of cesium from organs, which can be described with a fast and a slow exponential curve of excretion. On the 70th day, following the 30-days application, 2-8% of the first-day activity concentrations of 137Cs in organs (muscle, liver, bone) were detected. In the first two days, activity concentration of 241Am decreases twofold in both liver and bone. 35% of the maximum activity concentration of 241Am remained in bone and 15% in liver on the last day of the experiment.
Subject(s)
Radiation Monitoring , Soil Pollutants, Radioactive , Animal Feed/analysis , Animals , Cesium Radioisotopes/analysis , Chickens , Soil Pollutants, Radioactive/analysisABSTRACT
Data on the transfer of artificial radionuclides from the environment to the food supply is necessary for internal dose assessment. There is a necessity for expanding and improving the available information on these factors in order to make better dose models for specific scenarios. This paper describes the results of a field experiment with broiler chickens on the transfer factor (Ff) and concentration ratio (CR) for the long-term intake of 241Am and 137Cs with grass meal and soil. The broilers were divided into two groups, each group had nine subgroups and each subgroup had three broilers. The radionuclide concentrations in the feed and the thigh muscle, thigh bone, and liver of 54 broilers divided between the grass meal and soil groups were evaluated by gamma spectrometry for 241Am and 137Cs. The duration of feeding with "contaminated" sources ranged between 1-70 days. The equilibrium stage of 241Am in muscle and bone occurs on the 1st and 40th day, respectively; for 137Cs in muscle- 30th days of intake and for liver and bone- 7th days. For 241Am, the liver did not reach equilibrium stage during the 70 days of intake. Ff of 137Cs in the "forage-muscle" and "soil-muscle" systems were determined as 1.9±0.3 and 0.18±0.05; Ff of 241Am in the "soil-muscle" system was-7.5×10-5.
Subject(s)
Americium/analysis , Cesium Radioisotopes/analysis , Chickens , Food Contamination, Radioactive/analysis , Poultry , Soil Pollutants, Radioactive/analysis , Americium/metabolism , Animal Feed/analysis , Animals , Cesium Radioisotopes/metabolism , Chickens/metabolism , Food Supply , Poultry/metabolism , Soil Pollutants, Radioactive/metabolismABSTRACT
Horses are important food sources in several countries however, data on their radionuclide uptake is less available than for many other farm animals. Information on the transfer of artificial radioisotopes from the environment to the food supply is necessary for internal dose assessment and assuring the safety of the population relying on this food source. This study provides data for a less studied farm animal and, in the case of 241Am and 239+240Pu, relatively poorly studied radionuclides with respect to transfer to animal products. The transfer parameters for 239+240Pu, 241Am, 137Cs and 90Sr to the organs of 1-year old fillies, 10-year old mares and through the placental barrier into foetuses were quantified after 60-days feeding with contaminated soil or diet contaminated by a leachate solution. The transfer of radionuclides from ingested soil to tissues was generally lower, by up to three orders of magnitude, than from a diet contaminated by a leachate solution. The ingestion of soil is a particularly important source of radionuclide intake to grazing animals in the Semipalatinsk Test Site. For 241Am there is a lack of available data, the two singular entries for mutton and beef in the IAEA handbook are higher than all values observed in the current study. The maximum observed transfer factor for 241Am was 72 ± 22*10-5 d kg-1 FW in the liver of the mare fed with leachate contaminated feed. For 239+240Pu the maximum transfer factor was 31.8 ± 8*10-5 d kg-1 FW observed also in the liver of the mare fed with leachate contaminated feed. The filly fed with leachate contaminated feed had the highest transfer parameter value for 137Cs, 35.3*10-3 d kg-1 FW. The highest 90Sr transfer factor was found in the ribs of the filly fed leachate contaminated feed, 720 ± 144 *10-3 d kg-1 FW. The results presented in this paper can be used to improve the current internal dose estimates from the ingestion of horse meat produced in the area, however they are based on a low sample size; future studies need to use a larger number of animals.
Subject(s)
Cesium Radioisotopes , Horses , Radiation Monitoring , Soil Pollutants, Radioactive , Strontium Radioisotopes , Animals , Cattle , Cesium Radioisotopes/pharmacokinetics , Female , Pregnancy , Soil Pollutants, Radioactive/pharmacokinetics , Strontium Radioisotopes/pharmacokineticsABSTRACT
Monitoring of radioactive materials has been reported in rivers and soil in Fukushima post the Fukushima Daiichi Nuclear Power Plant accident in March 2011. However, there are few reports on the influence of this event on bacteria in forest soils and rivers. Therefore, through amplicon sequencing of 16S rDNA we compared the bacterial flora in river sediment soils from Fukushima prefecture and from an area not exposed to radioactive contamination, Aomori prefecture. The bacterial composition in the Aomori prefecture soil and Fukushima soil were found to be very similar at the phylum level. However, Fukushima soil had significantly fewer Bacteroidetes than the Aomori soil (p = 0.014), while the content of Firmicutes and Latescibacteria (WS3) was significantly higher (p = 0.001, 0.013 respectively). However, no increase in the content of radioactive-resistant bacteria was observed. In future studies, it is necessary to standardise the conditions for soil collection to assess its content of radioactive substances.
Subject(s)
Bacteria/genetics , Geologic Sediments/analysis , RNA, Ribosomal, 16S/genetics , Radiation Monitoring/methods , Rivers/chemistry , Soil Pollutants, Radioactive/analysis , Water Pollutants, Radioactive/analysis , Bacteria/classification , Fukushima Nuclear Accident , Nuclear Power PlantsABSTRACT
The latest car-borne survey was carried out by Hirosaki University in order to grasp the local distribution of the absorbed dose rate in air after the evacuation order was lifted on Namie Town in 2017. The car-borne survey of absorbed dose rate in air was carried out on most of the roads which were accessible by car in Namie Town using a 3-in × 3-in NaI(Tl) scintillation spectrometer. The range of the absorbed dose rate in air was calculated to be 0.041-11 µGy h-1. The distribution maps of the absorbed dose rate in air were drawn based on the data obtained during the surveys in 2011, 2015 and 2017. The comparison of these absorbed dose rates in air suggests that the elevated absorbed dose rate in air in Namie Town caused by the FDNPP accident may be decreasing faster than natural decline which includes weathering effect and physical decay due to the artificial decontamination.
Subject(s)
Air Pollutants, Radioactive/analysis , Fukushima Nuclear Accident , Radiation Exposure/analysis , Radiation Monitoring/methods , Radioactive Fallout/analysis , Automobiles , Decontamination , Humans , Nuclear Power Plants , Radiation Dosage , Radiation Monitoring/instrumentationABSTRACT
At the Thermal Power Plant in Oroszlány (Hungary), a huge amount of by-products have been produced since 1961. In this survey, coal and other by-products were examined (fly ash, bottom ash, fluidised bed bottom ash, gypsum and slurry-type ash). The natural isotopes were determined using an HPGe detector. It was found that the radionuclide content of coal was significantly lower ((226)Ra = 45.3±6.3, (232)Th = 26.3±5.7 and (40)K = 210±21 Bq kg(-1)) than that in the case of ashes other than the fluidised type. The average values of the bottom ash-deposited in the largest quantities-were three times higher than those for coal ((226)Ra = 144±18, (232)Th = 84.3±14 and (40)K = 260±25 Bq kg(-1)). In the case of fractionised bottom ash, the radionuclide content of <0.1 mm was 45 % higher than that of >1.6 mm and the massic radon exhalation of <0.1 mm was approximately four times higher than that above this range.
Subject(s)
Background Radiation , Coal/analysis , Industrial Waste/statistics & numerical data , Power Plants/statistics & numerical data , Radiation Exposure/statistics & numerical data , Radioisotopes/analysis , Hungary , Industrial Waste/analysis , Radiation Dosage , Radiation Exposure/analysis , Radiation Monitoring/methods , Radiation Monitoring/statistics & numerical dataABSTRACT
The aim of this study is to explore the correlations between the properties of the source's material and the thoron flux produced. This means a complex procedure that involves morphological characterisation (the determination of specific surface area and pore size distribution) and thoron emanation and exhalation measurements as well. In this work, the preparation of 27 thoron sources has been carried out. Three types of ceramics with different morphological properties were used as a matrix material with three different thorium contents. Spheres were formed from the dollop, and they were fired at different temperatures (200, 600 and 900°C). The phase analysis of the samples was performed by powder X-ray diffraction. The pore size distribution was determined by mercury penetration. The thoron emanation was measured using an accumulation chamber; the measured thoron emanation coefficients were from 0.34 ± 0.03 to 7.69 ± 0.13 %. Based on the results, the preparation parameters of the thoron source optimised for the calibration procedure have been given.
Subject(s)
Ceramics/chemistry , Ceramics/standards , Radiation Monitoring/instrumentation , Radiation Monitoring/standards , Radon/analysis , Radon/standards , Calibration/standards , Equipment Design , Equipment Failure Analysis , Materials Testing , Radiation Monitoring/methods , Radon/chemistry , Reference Values , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
The main goal of PUR experiment (phage and uracil response) is to examine and quantify the effect of specific space conditions on nucleic acid models. To achieve this an improved method was elaborated for the preparation of DNA and bacteriophage thin films. The homogeneity of the films was controlled by UV spectroscopy and microscopy. To provide experimental evidence for the hypothesis that interplanetary transfer of the genetic material is possible, phage T7 and isolated T7 DNA thin films have been exposed to selected space conditions: intense UVC radiation (lambda=254 nm) and high vacuum (10(-4) Pa). The effects of DNA hydration, conformation and packing on UV radiation damage were examined. Characteristic changes in the absorption spectrum, in the electrophoretic pattern of DNA and the decrease of the amount of PCR products have been detected indicating the photodamage of isolated and intraphage DNA.
Subject(s)
Bacteriophage T7/genetics , Bacteriophage T7/radiation effects , DNA, Bacterial/radiation effects , Ultraviolet Rays , Uracil/radiation effects , Vacuum , DNA, Viral/radiation effects , Dose-Response Relationship, Radiation , Extraterrestrial Environment , Radiation Dosage , SpectrophotometryABSTRACT
Phage T7 can be used as a biological dosimeter; its reading, the biologically effective dose (BED), is proportional to the inactivation rate |ln (n/n0)|. For the measurement of DNA damage in phage T7 dosimeter, a quantitative polymerase chain reaction (QPCR) methodology has been developed using 555 and 3826 bp fragments of phage T7 DNA. Both optimized reactions are so robust that an equally good amplification was obtained when intact phage T7 was used in the reaction mixture. In the biologically relevant dose range a good correlation was obtained between the BED of the phage T7 dosimeter and the amount of ultraviolet (UV) photoproducts determined by QPCR with both fragments under the effect of five various UV sources. A significant decrease in the yield of photoproducts was detected by QPCR in isolated T7 DNA and in heated phage compared with intraphage DNA with all irradiation sources. Because the yield of photoproducts was the same in B, C and A conformational states of T7 DNA, a possible explanation for modulation of photoproduct frequency in intraphage T7 DNA is that the presence of bound phage proteins induces an alteration in DNA structure that can result in increased induction of photoproducts.
Subject(s)
Bacteriophage T7/genetics , DNA, Viral/genetics , Polymerase Chain Reaction/methods , Base Sequence , DNA Primers , DNA, Viral/radiation effects , Ultraviolet RaysABSTRACT
The nutritive value of dog foods declared by the manufacturer as nutritionally complete and balanced can be best assessed by feeding trials with dogs. A protocol of a feeding trial has been developed and tested with working dogs fed two different commercial complete and balanced diets for 8 weeks. The parameters used for evaluating the effect of diets were general health status, body and hair coat condition, change of body weight, haematological parameters (white blood cell (WBC) count, red blood cell (RBC) count, haemoglobin, packed cell volume), and biochemical parameters in blood serum (alanine aminotransferase, urea, albumin). The trial protocol proved to be appropriate to monitor the dogs' nutritional status and to reveal differences between diets. This method of evaluation is recommended for use in supporting the nutritional claims (labelling) of dog foods.
Subject(s)
Animal Feed/standards , Dogs/physiology , Nutritional Requirements , Animals , Food Labeling , Research DesignABSTRACT
Coeliac disease is a life-long disorder characterised by small-intestinal mucosal damage caused by gluten. The treatment, gluten-free diet, leads to mucosal restoration and reduces the risk of malignant and non-malignant complications. According to our recent results, cumulative incidence in Croatian children is 1:519 life-births. Coeliac disease presents early, mostly with typical symptoms. We investigated possible influences of breast-feeding duration and time of gluten introduction on such presentation of the disease. Study included coeliacs born in Medimurje between 1985 and 1994 (N = 31). Patients' adherence to treatment was also studied. Although short breast-feeding (mean 2.9 months) and early gluten introduction (mean 4.9 months) were shown, no correlation was found between those factors and time of the disease presentation. Concerning adherence to gluten-free diet, only 50% of patients maintained it strictly, 23% irregularly, while 27% were on normal diet. In order to improve it, regular follow-ups are recommended.
Subject(s)
Breast Feeding , Celiac Disease/etiology , Diet , Celiac Disease/epidemiology , Child , Child, Preschool , Croatia/epidemiology , Female , Glutens , Humans , Incidence , Infant , Infant Nutritional Physiological Phenomena , Infant, Newborn , Male , Risk FactorsABSTRACT
Coeliac disease is a permanent intolerance to gluten, producing small-intestinal lesions. Its incidence in European countries varies from 1:400 to 1:2000, while there are no such epidemiological data for Croatia. Therefore, we investigated the incidence of coeliac disease for ten-year period in one well-defined region. Also, data concerning age at diagnosis and symptoms at the disease onset were collected. The cumulative incidence was 1.9:1000 life-births. The disease presented typically in more than 60% of cases. In 65% of patients, symptoms appeared during the first 2 years of life, while, when diagnosed, 45% were below 2 years. Also, it was shown that coeliac disease presented significantly later in children diagnosed during the last five years (p < 0.05). In conclusion, coeliac disease in Croatia is more frequent than previously suspected. It presents early, mostly with classical symptoms, although a tendency towards later ages of diagnosis was observed during the last few years.
Subject(s)
Celiac Disease/epidemiology , Age Factors , Child , Child, Preschool , Croatia/epidemiology , Female , Humans , Incidence , Infant , MaleABSTRACT
Methionine and its derivatives are used as feed supplements. The objective of this study was to compare the effectiveness of DL-methionine (MET), DL-methionine-hydroxy-analogue (2-hydroxy-4-methylthio-butyric acid, MHA), and DL-S methyl-methionine-sulphonium-chloride (SMM) in rats using low- (10 g/100g, BD10), medium-(15g/100g, BD15) and high-protein (20 g/100 g, BD20) diets. In a 10-day growth assay with weaning male rats (Wistar, SPF, LATI, Gödöllo, Hungary, 6 rats/group) methionine-deficient basic diets (BD10, BD15, BD20) were supplemented with 0, 1.5 ad 3.0 g/kg MET, MHA OR SMM. Extracted soybean meal was used as sole protein source. A protein-free diet was used for determining net protein ratio (NPR) indices. The weight gain of rats fed test diets fortified with 1.5 and 3.0 g/kg MET, MHA, or SMM was significantly higher (p < 0.05) than that obtained with the unfortified diets. The NPR index of the diets was increased by MET, MHA or SMM supplementation, which increase was significant (p < 0.05) at 3.0 g/kg fortification level. However, there were no significant differences between the efficiencies of methionine derivatives on the same dietary protein levels. The weight gains of the rats were higher and the NPR indices of the diets were lower at a higher dietary protein level.
Subject(s)
Dietary Proteins/metabolism , Growth/drug effects , Methionine/pharmacology , Weight Gain/drug effects , Animal Feed , Animals , Male , Rats , Rats, WistarABSTRACT
In order to offer methods for assessing the protein quality of dog foods, eight commercial dry-type complete dog foods were analysed by in vitro chemical methods (crude protein, amino acid composition, in vitro pepsin digestibility) and rat growth trial (weight gain = WG, feed efficiency = FE, protein efficiency ratio = PER, net protein ratio = NPR, and net protein utilisation = NPU). Three individual samples were taken from each dog food and their homogenous mixture was used as an ingredient for the test diets fed to six rats per diet. All dog food samples were used as a single protein source in isonitrogenous (10% crude protein) and isoenergetic (ME = 14.9 MJ/kg) complete diets. Rat weight gains showed significant differences among most of the test diets as a consequence of the differences in protein quality of the dog food samples. The protein quality indices of the dog food products showed significant variations. The measured ranges of protein quality indices of the samples were as follows: WG = -5.4-21.4 g; FE = 0-0.25 g/g; PER = 0-2.54 g/g; NPR = 1.06-3.52 g/g; NPU = 19.93-65.93%. The limiting amino acid, the sum of essential amino acids and the chemical scores were calculated from gross amino acid composition. Tryptophan was the first limiting amino acids in all samples but one. Methionine was found to be the second limiting amino acid. The crude protein content of the samples showed no correlation with indices of protein quality, indicating that the declaration of crude protein is not a sufficient information to judge the protein quality of dog foods. The declaration of NPR, or NPU indices may be recommended for labelling the protein quality of premium-type dog foods.
Subject(s)
Animal Feed , Animal Nutritional Physiological Phenomena , Dietary Proteins/standards , Dogs/physiology , Amino Acids, Essential/analysis , Animal Feed/standards , Animals , Body Weight , Chromatography, Ion Exchange , Dietary Proteins/analysis , Dietary Proteins/metabolism , Digestion , Male , Nutritive Value , Pepsin A/metabolism , Quality Control , Rats , Rats, Wistar , Reference Standards , Specific Pathogen-Free OrganismsABSTRACT
To meet the requirements of pigs a better supply of amino acids can be achieved by using ileal digestibility data of feed ingredients in least-cost feed formulation. Digestibility of amino acids can be improved by addition of multienzyme products, antimicrobial additives and probiotics. Protein accretion may be positively influenced by beta-adrenergic agonists. An adequate ratio of protein to dietary energy is essential to achieve optimal protein utilization. Nitrogen output can be minimized by improving feed efficiency and by eliminating antinutritional substances with adequate processing. The use of the ideal protein concept helps to minimize nitrogen excretion. Management and animal hygiene also have a significant impact on the overall nitrogen balance in animal production.
Subject(s)
Animal Feed , Dietary Proteins , Environmental Pollution/prevention & control , Nitrogen/metabolism , Adrenergic beta-Agonists/administration & dosage , Amino Acids , Animals , Digestion , Food Additives , Ileum , Poultry , SwineABSTRACT
The cellular electrophysiological effects of dridocainide (EGIS-3966), a novel class I antiarrhythmic agent, was studied using conventional microelectrode techniques in canine cardiac Purkinje fibres and papillary muscle preparations obtained from humans and guinea-pigs. In each preparation, dridocainide (0.6-2 mumol/l) decreased the maximum velocity of action potential upstroke (Vmax) in a frequency-dependent manner, although marked differences were observed in its effects in Purkinje fibre and ventricular muscle preparations. In canine Purkinje fibres, action potential duration measured at 50% and 90% of repolarization was decreased, while action potential duration measured at 10% of repolarization was increased by dridocainide. In addition, the plateau of the action potential was depressed by the drug. These changes in action potential configuration were not observed in guinea pig or human papillary muscles. The offset kinetics of the dridocainide-induced Vmax block were different in Purkinje fibres and in ventricular muscle: the slow time constant of recovery of Vmax was estimated to be 2.5 s in dog Purkinje fibre and 5-6 s in human and guinea-pig papillary muscle. In guinea-pig papillary muscle, the rate of onset of the Vmax block was 0.15 and 0.2 per action potential in the presence of 0.6 and 2 mumol/l dridocainide, respectively. Dridocainide also decreased the force of contraction in this preparation. On the basis of the present results, dridocainide appears to possess mixed class I.C and I.A properties, with I.C predominance in human and guinea-pig ventricular muscle. Present results also indicate that results of conventional classification of class I drugs may depend on the parameters chosen, as well as on the preparation selected.
Subject(s)
Anti-Arrhythmia Agents/pharmacology , Benzylidene Compounds/pharmacology , Heart/drug effects , Propanolamines/pharmacology , Action Potentials/drug effects , Animals , Dogs , Guinea Pigs , Heart/physiology , Humans , In Vitro Techniques , Purkinje Fibers/drug effects , Purkinje Fibers/physiologyABSTRACT
More than sixty 2-substituted-cycloalkanone-oxim-/2-hydroxy-3-dialkylamino/- propylethers were investigated on aconitine induced ventricular arrhythmia model in rats. According to the structure-activity relationships cyclohexanes containing diisopropylamine in the basic group were the most effective derivatives. Based on the highest per os activity and lowest toxicity EGIS-3966 (ED50 values 1.21 mg/kg iv. and 27.3 mg/kg per os) was selected for further development.
Subject(s)
Anti-Arrhythmia Agents/pharmacology , Cyclohexanes/pharmacology , Propanolamines/pharmacology , Aconitine , Animals , Anti-Arrhythmia Agents/chemistry , Anti-Arrhythmia Agents/toxicity , Cardiac Complexes, Premature/chemically induced , Cardiac Complexes, Premature/prevention & control , Cyclohexanes/chemical synthesis , Cyclohexanes/toxicity , Female , Male , Propanolamines/toxicity , Rats , Rats, Wistar , Structure-Activity RelationshipABSTRACT
The effect of several methionine sources (L-methionine = L-MET; DL-methionine = DL-MET, DL-S-methyl-methionine-sulphonium-chloride = SMM; N-hydroxymethyl-DL-methionine-Ca = NHM; methionine-hydroxy-analog free acid = MHA; methionine-sulphoxide = MSO) on rumen bacterial growth was studied using a new methodical approach which utilises a methionine free assay medium (Bacto Methionine Assay Media, Difco) supplemented by increasing quantities of the methionine sources and inoculated with one drop of diluted rumen bacteria. The optical density was measured after 18 h incubation on 39 degrees C. L- and DL-MET promoted the highest growth response, while SMM and NHM exerted significantly (p < 0.05) lower optical densities. MHA and MSO showed no growth response. The methodical approach and the possible bacterial strains, which might have contributed to the growth response have been discussed.
Subject(s)
Bacteria/drug effects , Methionine/analogs & derivatives , Methionine/pharmacology , Rumen/microbiology , Animals , Bacterial Physiological Phenomena , Cattle , Female , Stereoisomerism , Structure-Activity RelationshipABSTRACT
The appearance of blood in the seminal fluid is an alarming sign, with a rather inconstant origin. The causes of hematospermia are discussed based on a review of the literature and the authors' own experience with 84 patients. The importance of differential diagnosis is emphasized and a diagnostic scheme is presented. Therapeutic opportunities depending on etiology are discussed. It is concluded that although hematospermia is an often self-limiting sign, resolving in a few weeks, all patients should undergo a careful investigation to rule out the presence of malignancy or other significant disease.
Subject(s)
Blood , Male Urogenital Diseases/physiopathology , Semen , Humans , MaleABSTRACT
Environmental pollution by faecal nitrogen excretion motivates a renewed interest in optimising protein utilization of growing-finishing pigs in intensive pig production areas. The importance of digestibility of proteins, availability of amino acids, and the extent of protein retention is emphasized for reducing nitrogen excretion. The principles of various chemical, microbiological, biochemical and biological methods in feed protein quality evaluation offering a better adjustment of protein supply to the requirements of the animal are surveyed.