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Journal Article 2001; 22(1): 53-73 PubMed PMID: 11393163 Citation  Keywords:  Adrenal Glands:physiology, Animals, Biological Clocks, Blood Pressure:physiology, Chronobiology Disorders:physiopathology, Chronobiology Phenomena, Chronotherapy, Circadian Rhythm:physiology, Drug Administration Schedule, Genomics, Homeostasis, Humans, Pi.   

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Comparative Study 2013; 34(Suppl 2): 74-78 PubMed PMID: 24362096 Citation  Keywords:  Absorption, Animals, Biological Availability, Chlorides:administration & dosage, Cholinesterase Reactivators:administration & dosage, Female, Injections, Intramuscular, Injections, Intravenous, Oximes:administration & dosage, Pyridinium Compounds:administ.   

OBJECTIVES: Oxime HI-6 is an acetylcholinesterase reactivator therapeutically efficient against nerve agents. Because of their physico-chemical properties, oximes are typically applied intramuscularly (i.m.). This route of administration has also some disadvantages, and alternative strategies ought to be examined. We evaluated the pharmacokinetic profiles of two HI-6 salts after their intravenous (i.v.) administration, and compare the results with the known pharmacokinetics after i.m. administration.

METHODS: Pigs were administered with HI-6 salts (i.v), either HI-6 dichloride (10.71 mg/kg) or molar equivalent HI-6 dimethansulphonate (13.59 mg/kg). Doses of the HI-6 salts corresponded with a standard HI-6 dichloride dose in one autoinjector (500 mg) and were recalculated for one kilogram of body weight.

RESULTS: The main pharmacokinetic parameters are comparable after i.v. and i.m. HI-6 administration. The compared pharmacokinetic parameters were half-life, terminal rate constant, mean residence time of the molecule in the body, clearance, and the apparent volume in the terminal phase. The bioavailability after i.m. administration was comparable with that of i.v.; these results suggest that the oxime is well released from the muscle depot. Significant differences were found in parameters Cmax and Tmax which are important in cases of emergency when rapidity and bioavailability are paramount for the success of treatment.

CONCLUSIONS: I.v. administration should solve the problem of rapid clearance. Infusion or bolus administration may be considered as a logical subsequent step in oxime treatment strategy. The main advantage is in maintenance of an effective therapeutic plasma concentration, a more easily achievable effective therapeutic concentration, and fewer local adverse reactions....

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Journal Article 2013; 34(3): 177-183 PubMed PMID: 23685415 Citation  Keywords:  Animals, Biological Evolution, Gonadotropin-Releasing Hormone:physiology, Hagfishes:anatomy & histology, Neuroanatomy, Neurosecretory Systems:anatomy & histology, Reproduction:physiology,.   

: The family Myxinidae embraces all hagfish species, and occupies an evolutionary niche intermediate between ancestral vertebrates and the gnathostomes (jawed vertebrates). Gonadotropin releasing hormone (GnRH) modulates neuroendocrine activity in vertebrates and works in the context of the hypothalamic-pituitary (H-P) axis. The appearance of this neuroendocrine axis marks one of the most crucial developmental achievements in vertebrate evolution, because it enabled further diversification in general growth, metabolism, osmoregulation and reproduction as jawed vertebrates evolved. GnRH studies in hagfish draw attention because such work may be considered as providing proxy data for similar investigations conducted upon long extinct species. Indeed, the fossil record reveals little anatomical difference between those hagfish living 300 million years ago and their modern descendants. Accordingly, the hagfish can offer important evolutionary lessons as they have some highly unusual characteristics not seen in any other vertebrate; they retain many representative features of an ancestral state from which all vertebrates originated. Indeed, because central control of reproduction is perhaps the most basic function of the vertebrate H-P axis, and given the importance of GnRH in this network, research on GnRH in hagfish can help elucidate the early evolution of the H-P system itself. Like all vertebrates, hagfish have a functional hypothalamic area and a pituitary gland, constituting a basic H-P axis. But what role does GnRH play in the reproductive system of this "living fossil"? How can understanding GnRH in hagfish help advance the knowledge of vertebrate neuroendocrinology? Here, information on neuroendocrine function and the role of GnRH specifically in this very basal vertebrate is reviewed....

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Journal Article 2001; 22(1): 53-73 PubMed PMID: 11393163 Citation  Keywords:  Adrenal Glands:physiology, Animals, Biological Clocks, Blood Pressure:physiology, Chronobiology Disorders:physiopathology, Chronobiology Phenomena, Chronotherapy, Circadian Rhythm:physiology, Drug Administration Schedule, Genomics, Homeostasis, Humans, Pi.   

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Journal Article 2012; 33(Suppl 3): 113-119 PubMed PMID: 23353853 Citation  Keywords:  Animals, Chemical and Drug Induced Liver Injury:metabolism, Dose-Response Relationship, Drug, Gills:drug effects, Hepatocytes:drug effects, Herbicides:pharmacokinetics, Kidney:drug effects, Models, Biological, Thiobarbituric Acid Reactive Substances:metab.   

OBJECTIVES: Terbuthylazine belongs to the group of symmetrical triazine herbicides used extensively in agriculture and non-agricultural sites, primarily to control broadleaf and some grassy weeds that have become ubiquitous contaminants of the environment. The aim of this study was to assess the impact of terbuthylazine in surface waters on fish under experimental conditions. The effects of subchronic exposure to terbuthylazine on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver), and on the activity of some biochemical parameters - glutathione S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GPx) and on the concentration of thiobarbituric acid reactive substances (TBARS) in Danio rerio were investigated during a 28 day toxicity test.

METHODS: Juvenile growth tests were performed on Danio rerio according to OECD guideline No. 215. Fish at the age of 30 days were exposed for 28 days to a range of sublethal concentrations of terbuthylazine (0.55 - environmental concentration, 150, 400, 700 and 1000 μg/L).

RESULTS: There were no significant differences (p<0.05) between the specific growth rates (r) of the test groups and control group. Histopathological examination revealed pathological changes only in the liver in fish exposed to terbuthylazine at concentrations of 700 and 1000 μg/L. Significant differences (p<0.05) in activities of biochemical markers were found in GST (400, 700 and 1000 μg/L), GR (700 and 1000 μg/L), significant differences (p<0.05) of TBARS concentration were found at 1000 μg/L.

CONCLUSIONS: Based on the results of growth rate, the histopathological examination of selected organs, and the results of biochemical parameters, it was found that the environmental concentration of terbuthylazine did not have any effects on juvenile D. rerio. The values of NOEC and LOEC for terbuthylazine for juvenile D. rerio were 150 μg/L and 400 μg/L....

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Comparative Study 2012; 33(Suppl 3): 107-112 PubMed PMID: 23353852 Citation  Keywords:  Biological Assay, Biomass, Chlorophyta:drug effects, Dose-Response Relationship, Drug, Ecosystem, Platinum:toxicity, Platinum Compounds:toxicity, Toxicity Tests, Water Pollutants, Chemical:toxicity,.   

OBJECTIVES: An enhanced worldwide application of platinum group elements (PGE), in particular platinum, has been observed during recent decades. An increased concentration of PGE was determined in collected samples of great amount of aqueous ecosystems.The aim was to compare phytotoxic effect of platinum (PtCl4) by performing two different bioassays on green algae Pseudokirchneriella subcapitata and macrophyte duckweed, Lemna minor. MEDTHODS: The algal experiment (Pseudokichneriella subcapitata) followed OECD 201, the concentration row for PtCl4 was: 0.05; 0.01; 0.25; 0.5; 1 µM. The duckweed (Lemna minor) experiment was conducted according to OECD 221, employed PtCl4 concentrations were: 5; 10; 25; 50; 100 µM. Plants were cultivated as a microbiotest, using micro-volumes.

RESULTS: The results of the algal test showed significant growth inhibition of the final biomass. The values of 72hEC5(µ), 72hEC10(µ), 72hEC20(µ) counted on a basis of average specific growth rate (µ) were 0.31 µM, 0.58 µM and 1.12 µM of PtCl4, respectively. The values, obtained on a basis of the area under the growth curves (A), were 0.04 µM (72hEC5(A)), 0.24 µM (72hEC10(A)) and 0.64 µM (72hEC20(A)). The experiment with duckweed showed 50% of growth inhibition and the values of 168hEC50(µ) were 19.55 µM and 168hEC50(A) 13.63 µM of PtCl4.

CONCLUSION: The fronds of duckweed showed strong adverse effect of platinum influence (chlorosis, necrosis). The algal test and the estimation of 72hEC5(A) appears to be the most sensitive....

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Journal Article 2012; 33(Suppl 3): 90-95 PubMed PMID: 23353850 Citation  Keywords:  Animals, Carps:embryology, Czech Republic, Dose-Response Relationship, Drug, Embryo, Nonmammalian:drug effects, Female, Herbicides:toxicity, Kidney:drug effects, Male, Models, Biological, Ovum:drug effects, Rivers:chemistry, Simazine:toxicity, Toxicity Te.   

OBJECTIVES: The aim of this study is to assess the toxicity of simazine in different developmental stages of common carp (Cyprinus carpio) on the basis of mortality, early ontogeny, occurrence of morphological anomalies, growth rate, and Fulton's condition factor during and at the conclusion of the test.

DESIGN: The toxicity tests were performed on carp according to OECD 210 methodologies. The developmental stages of carp were exposed to simazine at four concentrations, 0.06, (reported concentration in Czech rivers), 60, 600, and 3000 µg/l for 36 days and compared to carp in a non-treated control group.

RESULTS: Simazine in concentration 0.06 µg/l had no effect on early life stages of carp. Simazine in concentration 600 and 3000 µg/l caused decrease of mass and total length of carp. Fish exposed to three highest levels of simazine showed alteration of tubular system of caudal kidney. On the basis of histopatological changes the values of LOEC = 60 µg/l, NOEC = 0.06 µg/l for simazine were estimated.

CONCLUSIONS: Chronic simazine exposure of early-life stages of common carp affected their growth rate, and histology. Some of the changes were observed only at higher exposures (600, 3000 µg/l), but change founded in caudal kidney was affected in fish exposed to the second lowest concentration tested (i.e., 60 µg/l), which is about 10 µg/l higher than reported in Colorado rivers in recent years. Concentrations of simazine in World rivers have been reported to generally vary in the range 0.0003-49.20 µg/l....

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Journal Article 2012; 33(6): 636-642 PubMed PMID: 23160222 Citation  Keywords:  Adaptation, Psychological:physiology, Adolescent, Biological Evolution, Dominance-Subordination, Female, Hierarchy, Social, Humans, Male, Masochism:physiopathology, Sadism:physiopathology, Sexual Behavior:physiology, Social Behavior, Surveys and Questionn.   

OBJECTIVES: We theorize that sexual arousal by dominance and submission may be connected to a reproduction strategy respecting a reached social dominance rank (a common reproduction strategy in socially living mammals), while the preference for "bondage" may be derived from an opportunistic strategy when being unable to compete for hierarchic rank (an alternative reproductive strategy that co-occurs frequently with the above-named main strategy). The answers to questions dealing with hierarchy in character should correlate exclusively with sexual arousal connected to any kind of expression of a hierarchy, but not with bondage.

DESIGN AND SETTINGS: The data were obtained from young adults (157 males and 183 females aged 18-20, with mean 18.4 years) via questionnaires.

RESULTS: Seven out of eight questions dealing with hierarchy correlated with sexual arousal by dominance and submission in men (Spearman's r=0.169-0.313; p<0.05 - p<0.001), two questions correlated with sexual arousal by dominance and submission in women (Spearman's r=0.32-0.166, p<0.001, p<0.05). THE MAIN FINDINGS: The questions dealing with hierarchy correlated with sexual arousal by dominance and submission while no answers correlated with bondage, neither in men nor in women.

CONCLUSION: The preference for sexual arousal by dominance and submission may be connected to strategy respecting rank, while the preference for "bondage" may be derived from an opportunistic strategy that may be essential for possible partner problems solution. From the evolutionary biology point of view, these patterns of sadomasochistic sex appear as adaptive rather than as pathology....

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