Robert Toman

Prof. Dr. Robert Toman

Institute of Animal Husbandry, Slovak University of Agriculture in Nitra, Nitra, Nitriansky, Slovakia
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Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 August 2016 in Reproductive Biology and Endocrinology
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Journal Article
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MAMaria Adamkovicova
Maria Adamkovicova
RTRobert Toman
Robert Toman
MMMonika Martiniaková
Monika Martiniaková
RORadoslav Omelka
Radoslav Omelka
RBRamona Babosova
Ramona Babosova
Peter MassányiPeter Massányi
Peter Massányi
Humans are ubiquitously exposed to multiple environmental contaminants. Consequences of combined action on the reproductive system remain unknown. This study aimed to assess single and joint effects of cadmium and diazinon exposure on sperm quality parameters. Male adult Wistar rats were randomized into 4 groups of ten animals each. Group A was used as a control, animals from group B were exposed to cadmium (30 mg/L), rats from group C were administered with diazinon (40 mg/L), and rats from group D were exposed simultaneously to cadmium (30 mg/L) and diazinon (40 mg/L) via drinking water for 90 days. Sperm morphology and motility were evaluated using a bright field microscope and a computer-assisted semen analysis. The percentage of motile spermatozoa and morphologically normal sperm was markedly reduced in rats from the group B. Rats from the C group showed an increase in velocity parameters, amplitude of lateral head displacement, decrease in beat-cross frequency, and an increase in abnormal sperm morphology. Simultaneous coexposure to cadmium and diazinon increased distance and velocity parameters, and amplitude of lateral head displacement. Reductions were observed in straightness, linearity, wobble, and beat-cross frequency. The decreased normal sperm morphology rates were related to defects of the sperm tail. Exposure to cadmium and diazinon at relatively low doses impairs sperm quality and can reduce male fertility. Cadmium and diazinon caused significant changes on sperm morphology with varying effects on motility patterns. These parameters were significantly higher in the group D as compared to the group C. The findings have important implications for reproductive risk assessment of combined exposures to multiple chemicals.

1 January 2014 in The Scientific World Journal
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Journal Article
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MAMaria Adamkovicova
Maria Adamkovicova
RTRobert Toman
Robert Toman
MCMichal Cabaj
Michal Cabaj
Peter MassányiPeter Massányi
Peter Massányi
MMMonika Martiniaková
Monika Martiniaková
HDHana Duranova
Hana Duranova
The present study aimed to elucidate the structural changes in testis and epididymis of adult rats following subchronic peroral administration of cadmium at 30 mg/L, diazinon at 40 mg/L, cadmium at 30 mg/L, and diazinon at 40 mg/L, respectively. At the end of 90-day experiment, the samples of the testes and epididymis were assayed by qualitative and quantitative histological methods. The testis and epididymis weights increased following exposure to cadmium and simultaneous exposure to cadmium and diazinon. Testicular damage following cadmium and diazinon coexposure was significantly less expressive than in groups with individual administration of these compounds. Cadmium caused a significant thickening of seminiferous epithelium, cellular degeneration, and necrosis. Desquamation of immature germ cells resulted in a significant increase of intraepithelial spaces and reduced tubule volume in all experimental groups. Vascular dilation and congestion were detected in the interstitial tissue. The changes in epididymal histology in the group exposed to cadmium and group exposed simultaneously included a reduction of epithelium, necrotic epithelial cells, vasoconstriction, and interstitial edema together with mononuclear cell infiltration. Results did not indicate a synergistic or any additional effect from the simultaneous administration of both toxicants. Further research is needed to determine the significance and the mechanism of the adverse effects.

1 July 2003 in Journal of Environmental Science and Health, Part A
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Peter MassányiPeter Massányi
Peter Massányi
FTFrieda Tataruch
Frieda Tataruch
JSJaroslav Slameka
Jaroslav Slameka
RTRobert Toman
Robert Toman
RJRastislav Jurík
Rastislav Jurík
Concentrations of lead, cadmium, and mercury in liver and kidneys of brown hares in relation to season, age, and sex were investigated. Over a period of one year 74 hares, 36 males and 38 females w...

24 September 2014 in Acta Veterinaria Scandinavica
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HDHana Duranova
Hana Duranova
MMMonika Martiniaková
Monika Martiniaková
RORadoslav Omelka
Radoslav Omelka
BGBirgit Grosskopf
Birgit Grosskopf
IBIvana Bobonova
Ivana Bobonova
RTRobert Toman
Robert Toman
Chronic exposure to cadmium (Cd), even at low concentrations, has an adverse impact on the skeletal system. Histologically, primary and secondary osteons as basic structural elements of compact bone can also be affected by several toxicants leading to changes in bone vascularization and mechanical properties of the bone. The current study was designed to investigate the effect of subchronic peroral exposure to Cd on femoral bone structure including histomorphometry of the osteons in adult male rats. In our study, 20 one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group, young males received a drinking water containing 30 mg of CdCl2/L, for 90 days. Ten one-month-old males without Cd intoxication served as a control group. After 90 days of daily peroral exposure, body weight, femoral weight, femoral length, cortical bone thickness and histological structure of the femora were analysed. We found that subchronic peroral application of Cd had no significant effect on body weight, femoral length and cortical bone thickness in adult rats. On the other hand, femoral weight was significantly increased (P < 0.05) in Cd-intoxicated rats. These rats also displayed different microstructure in the middle part of the compact bone where vascular canals expanded into central area of substantia compacta and supplied primary and secondary osteons. Additionally, a few resorption lacunae which are connected with an early stage of osteoporosis were identified in these individuals. Histomorphometrical evaluations showed that all variables (area, perimeter, maximum and minimum diameter) of the primary osteons' vascular canals, Haversian canals and secondary osteons were significantly decreased (P < 0.05) in the Cd group rats. This fact points to alterations in bone vascularization. Subchronic peroral exposure to Cd significantly influences femoral weight and histological structure of compact bone in adult male rats. It induces an early stage of osteoporosis and causes reduced bone vascularization. Histomorphometrical changes of primary and secondary osteons allow for the conclusion that the bone mechanical properties could be weakened in the Cd group rats. The current study significantly expands the knowledge on damaging action of Cd on the bone.

31 May 2007 in Journal of Environmental Science and Health, Part A
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Peter MassányiPeter Massányi
Peter Massányi
Norbert LukáčNorbert Lukáč
Norbert Lukáč
JSJana Slivkova
Jana Slivkova
Jaroslav KovacikJaroslav Kovacik
Jaroslav Kovacik
AMAlexander V. Makarevic
Alexander V. Makarevic
GFGrzegorz Formicki
Grzegorz Formicki
In this study effects of mercury administration on the kidney and testicular structure of adult rats were evaluated. Rats received mercury (HgCl2) in single intraperitoneal dose 20 mg HgCl2 (group A), 10 mg HgCl2 (group B) and 5 mg HgCl2 (group C) per kilogram of body weight and were killed after 48 hours following mercury administration. After the preparation of histological samples the results were compared with control group (K). In kidney decreased diameters of glomeruli and renal corpuscles, damaged tubules with affected quality of tubular cells and infiltration of interstitium were detected. Quantitative analysis demonstrated increased relative volume of tubules and renal corpuscles. Also the number of nuclei and glomeruli was increased in all experimental groups. The diameter of glomeruli and renal corpuscles was decreased. In testis undulation of basal membrane, dilatation of blood vessels in interstitium and occurrence of empty spaces in germinal epithelium were observed. Decreased relative volume of germinal epithelium, increased relative volume of interstitium and increased apoptosis occurrence suggest damaged interstitium and revealed occurrence of edemas. The relative volume of seminiferous tubules showed higher luminization. The number of nuclei was decreased in all experimental groups what is in positive relation with occurrence of empty spaces. Also other evaluated criteria demonstrated significant differences between control group and experimental groups. This study reports a negative effect of mercury on the structure and function of kidney and testes.

1 September 2005 in Ecotoxicology and Environmental Safety
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Journal Article
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RTRobert Toman
Robert Toman
Peter MassányiPeter Massányi
Peter Massányi
Norbert LukáčNorbert Lukáč
Norbert Lukáč
LDLadislav Ducsay
Ladislav Ducsay
JGJozef Golian
Jozef Golian