Psychostimulants, as well as cannabinoids, have been shown to
significantly affect a great variety of behaviors in both humans
and laboratory animals. Our previous studies have repeatedly
demonstrated that the application of the vehicle for
psychostimulants, i.e. saline, to control groups, generated
different behavioral test results compared to absolute naïve
controls (i.e. without any injection). Therefore, our present study
has set three goals: (1) to evaluate the effect of three different
psychostimulant drugs, (2) to evaluate the effect of three doses
of delta 9-tetrahydrocannabinol (THC), and (3) to evaluate the
effect of saline and ethanol injections vs sham injections and no
injection on spontaneous behavior of adult male rats. The
LABORAS test (Metris B.V., Netherlands) was used to examine
spontaneous locomotor activity and exploratory behavior in an
unknown environment over 1 h. In Experiment 1,
psychostimulant drugs were tested: single subcutaneous (s.c.)
injections of amphetamine (5 mg/kg), cocaine (5 mg/kg), and
3,4-methylenedioxymethamphetamine (MDMA) (5 mg/kg) were
applied prior to testing. Control animals received the same
volume (1 ml/kg) of s.c. saline. In Experiment 2, the effect of
three doses of THC (1, 2, and 5 mg/kg, s.c.) were examined.
An s.c. injection of vehicle (ethanol) was used as a control. In
Experiment 3, injections of saline and ethanol were compared to
the group receiving a sham s.c. injection and to a group of
absolute “naïve” controls. Our results demonstrated that (1) all
psychostimulants increased locomotion time, distance traveled,
and speed while decreasing immobility time of adult male rats
relative to saline controls. The most prominent effect was
associated with MDMA; (2) The effect of THC was dosedependent and was most apparent within the first 10 min of the
LABORAS test. (3) With regard to the effect of injection: absolute
controls (without injection) compared to animals injected with
ethanol, saline, or sham-injected displayed reduced immobility
time, traveled longer distances, and had increased speed. In
conclusion, our data showed drug dependent behavioral changes
in adult male rats after application of psychostimulants and
cannabinoids. Our findings also suggest that not only drugs but
the actual single injection per se also affects the behavior of
laboratory animals in an unknown environment. This effect
seems to be associated with the acute stress associated
with the injection.
The quality of stored blood can be deteriorated by hemolysis caused by free radicals. The purpose of this study was to elucidate whether neutrophile leukocytes are the source of free radicals in stored blood as in hemodialyzed patients. Resuspensions with low (LL) or high (HL) leukocyte concentrations were prepared from samples of twenty healthy volunteers. The samples were incubated for 10 days at 4 °C and then for one day at 37 °C. Markers of hemolysis and free radical metabolism were examined before and after incubation in LL and HL samples. In spite of the difference of leukocytes counts in LL and HL resuspensions (p<0.0001), the pre-incubation values of all laboratory parameters were practically identical. In post-storage samples, superoxide dismutase and glutathione peroxidase activities did not differ in either group. Reduced glutathione in erythrocytes and extracellular antioxidant capacity were insignificantly lower in HL resuspensions, but the increase of malondialdehyde was much more pronounced in the HL samples (p<0.0001). The degree of hemolysis, expressed as the extracellular increase of potassium (p<0.001), hemoglobin (p<0.05) and lactate dehydrogenase (p<0.05), was higher in the HL samples. Our results support the hypothesis that leukocytes participate in free radical production in stored blood., J. Racek, R. Herynková, V. Holeček, J. Faltysová, I. Krejčová., and Obsahuje bibliografii
Polycystic ovary syndrome (PCOS), the most common endocrinopathy in women (with a prevalence of 5-10 %), is characterized by hormonal and metabolic imbalance. Complexity of symptoms of close relatives of women with PCOS and genetic autosomal trait initiated a hypothesis about the existence of a male equivalent of PCOS. Premature alopecia was suggested as one of the signs of a male phenotype of this syndrome. The present study investigated a group of 30 men, in which premature hair loss started before 30 years of age. In all patients, their hormonal profile was determined. It was possible to form two subgroups. The first one showed similar hormonal changes as women with PCOS, the other had either no anomalies in steroid spectrum or just only lower level of sexual hormones binding globulin (SHBG). Both subgroups did not differ in either BMI or age. In all men with premature alopecia insulin tolerance test was also carried out and the occurrence of allele 3 INS VNTR was investigated, which is one of the candidate genes for PCOS. The subgroup with hormonal changes resembling those of women with PCOS showed a significantly higher insulin resistance than the group without these changes. About one third of the premature balding men showed the combination of hormonal shifts and higher insulin resistance. This frequency corresponds to the prevalence of PCOS in women. There was no significant difference between the two subgroups in the occurrence of allele 3 INS VNTR.
In this note, we prove that the countable compactness of {0, 1} R together with the Countable Axiom of Choice yields the existence of a nonmeasurable subset of . This is done by providing a family of nonmeasurable subsets of whose intersection with every non-negligible Lebesgue measurable set is still not Lebesgue measurable. We develop this note in three sections: the first presents the main result, the second recalls known results concerning non-Lebesgue measurability and its relations with the Axiom of Choice, the third is devoted to the proofs.
We tested the hypothesis that males of meadow pipits (Anthus pratensis) respond differentially to simulated territorial intrusions (song playback + bird model) by conspecific, related (tree pipit, Anthus trivialis), and unrelated individuals (willow warbler, Phylloscopus trochilus), and evaluated the effect of playback order. All tested males responded aggressively to the conspecific playback; reactions to heterospecific stimuli occurred only after previous excitation by the conspecific song and dummy, and were usually weaker. Apparently, although males were able to discriminate between playbacks, excitation by intrusion of a conspecific rival elicited an aggressive reaction to otherwise neutral stimuli. Reactions to heterospecific playbacks closely following the conspecific one did not differ significantly between congeneric and unrelated species. The response to a subsequent heterospecific stimulus, however, was taxon-dependent: congeneric species elicited a significantly stronger reaction than an unrelated one. We presume that this was due to the morphological similarity between pipits, and that the more intensive reaction could have been caused by stronger visual stimulus from the respective model. We discuss the potential benefits as well as limitations of using models (dummies) in playback experiments, and suggest that overexcitation by previous stimuli should be considered during experimental setup and data analysis in studies focusing both on interspecific aggressiveness and on neighbour-stranger interactions.
By a sign pattern (matrix) we mean an array whose entries are from the set $\lbrace +,-,0\rbrace $. The sign patterns $A$ for which every real matrix with sign pattern $A$ has the property that its inverse has sign pattern $A^T$ are characterized. Sign patterns $A$ for which some real matrix with sign pattern $A$ has that property are investigated. Some fundamental results as well as constructions concerning such sign pattern matrices are provided. The relation between these sign patterns and the sign patterns of orthogonal matrices is examined.
Large veteran trees are key structures sustaining biodiversity in wooded landscapes. Many organisms associated with
such trees are, however, also able to inhabit suitable trees with smaller diameters or other surrogate habitats. Understanding the
mechanisms behind the importance of veteran trees and the conditions enabling veteran tree specialists to exploit smaller trees
might help conservation efforts targeted at the diverse and highly endangered biota associated with veteran trees. To investigate
this, we studied local patterns in the exploitation of trees by a veteran tree specialist, the great capricorn beetle (Cerambyx cerdo),
at three sites with different soil characteristics, namely fl oodplain, dry-sandy and dry-rocky sites, where this beetle exploits oaks
of large (~1.5 m), medium (~0.75 m) and small (~0.25 m) diameters, respectively. We recorded the presence and number of exit
holes made by C. cerdo on each tree and related these to the characteristics of the trees: their diameters, openness of the canopy
around them and their state of health. The probability of occurrence and the number of exit holes increased with tree diameter,
canopy openness, and decreasing tree health, but these relationships differed considerably among the study sites. In dry conditions, trees of small diameters were more likely to be exploited by the beetle than in the fl oodplain. The number of exit holes, on
the other hand, was a function of tree diameter, with large trees sustaining more beetles and thus acting as larger habitat patches.
The species of oak affected the probability of exit hole presence as the sessile oak (Quercus petraea) and pedunculate oak (Q.
robur) were preferred over Turkey oak (Q. cerris). The slope orientation also affected the presence of exit holes as trees on slopes
with either an eastern or northern orientation were not exploited by the beetle. This study revealed a high level of between-site
variability in the tree characteristics relevant to predicting the occurrence of C. cerdo, mainly with respect to diameter. Therefore,
while the general patterns of habitat use and the fundamental niche of this beetle are well known, survival and protection of local
populations is dependent on site-specifi c characteristics. The realized niche of this beetle must therefore be carefully considered
when planning conservation management for a particular site. The results also signify that at some sites, small trees can, at least
temporarily, substitute for scarce large trees if the state of their health is managed using proper conservation measures.