Choice tests showed that tracks left by coccinellid larvae have generally little effect on oviposition site selection by chrysopid females. Fresh tracks of first instar larvae of the coccinellid species Coccinella septempunctata, Cycloneda limbifer, Leis dimidiata and Semiadalia undecimnotata, did not deter females of the chrysopid Chrysopa oculata from laying eggs. Females of Chrysopa perla avoided ovipositing only on substrates with tracks of L. dimidiata larvae.
During a three year study in rapeseed-mustard crop, the response of two ladybird species, Coccinella septempunctata and Menochilus sexmaculatus was dependent upon density and time of appearance of their prey. Mustard aphid, Lipaphis erysimi appeared during the second (2000 and 2001) and last (2002) week of January. Aphid appearance was highly dependent on the phenological stage of the host plant. It appeared earlier in rapeseed, Brassica campestris var. BSH-1 than mustard, Brassica juncea var. RH-30. The ladybird beetle's eggs were observed in the last week of January, 4-5 weeks before the maximum aphid population. A correlation between aphid number and the abundance of ladybirds' life stages (egg, larva and beetle) on these host plants revealed that the egg and larval density was positively correlated to aphid numbers. Adult beetles, however, did not show significant positive correlation with aphid numbers during all the three years of study. Coccinella septempunctata was more abundant than Menochilus sexmaculatus in these crops. Menochilus sexmaculatus population disappeared earlier than Coccinella septempunctata which was abundant until end of the crop season.
Determination of response of cortisol and its metabolites to different stimuli may be important for adrenal gland disorders. To date, only one metabolite, cortisone, has been followed in stimulation tests of the adrenal gland. We aimed to describe a response of cortisol metabolites to the standard short Synacthen test (HDST), insulin tolerance test (ITT), low dose Synacthen test (LDST) and medium dose Synacthen test (MDST). Sixty healthy subjects were investigated: 30 men and 30 women. Plasma for measurements of cortisol and its metabolites was obtained before and 30th and 60th min after Synacthen and insulin administration. The cut-off 500 nmol/l of cortisol was reached after stimulation in all of tests, the maximal stimulation level was reached in 60th min in all of the tests except for LDST. The response of cortisol and its metabolites at 30th and 60th min strongly correlated in all of the tests except for LDST. Cortisol and its metabolites increased after stimulation; in contrast, cortisone and its metabolites decreased. We showed that the response of the cortisol metabolites during the Synacthen tests and ITT well correlated, and the MDST showed similar response compared to HDST. The decrease in cortisone metabolites may correspond to the regeneration of cortisol from cortisone in response to stimulation test., K. Simunkova, M. Duskova, M. Kosak, M. Krsek, V. Hana, M. Hill, H. Jandikova, H. Pospisilova, M. Sramkova, E. Bifulco, L. Starka., and Obsahuje bibliografii
We studied the effects of the overstory canopy cover on ground-dwelling harvestmen communities in European beech forests in the Western Carpathian Mts. We analyzed the differences in species richness, abundance and composition in two tree canopy cover categories (closed and open canopy). Overall, 1765 individuals belonging to 16 species were caught using pitfall traps. Repeated-measures ANOVA revealed that under both closed and open canopies a similar absolute and rarefied species richness and number of individuals (standardized to 100 pitfall trap days) were caught, and that both species richness and abundance were affected by the season (i.e., time of trap replacement); yet the total number of individuals trapped was more than two times greater under the open canopy than under the closed canopy. Despite the subtle differences in the taxonomic composition of the catches under the open and closed canopies revealed by DCA followed by RDA, the composition of ground-dwelling harvestmen assemblages differed under the two canopy covers. The open canopy was more suitable for heliophilic, xerothermic eurytopic harvestmen species typical for open and ecotonal habitats, such as Egaenus convexus (C.L. Koch) and Oligolophus tridens (C.L. Koch) but still suitable for hemihygrophilic Lophopilio palpinalis (Herbst). The closed canopy stands were preferred by shade-tolerant, hygrophilic eurytopic harvestmen species, such as Trogulus sp. Latreille, Dicranolasma scabrum (Herbst) and Platybunus bucephalus (C.L. Koch). Our results highlight the importance of intra-habitat heterogeneity of a harvestmen community., Ľudmila Černecká, Ivan Mihál, Benjamín Jarčuška., and Obsahuje bibliografii
We investigated the effects of repeated hyperthermic bouts on the heat shock response of heat s hock protein ( HSP ) 72 in skeletal muscle. Rats were assigned to control and hyperthermia groups which were exposed to heated water at 42 °C. The hyperthermia group was further divided into sub -groups: a single bout (H30) or four bouts of hyperthermia for 30 min (H30x4). There was an increase in HSP72 protein content of the H30 groups in both extensor digitorum longus (EDL) and soleus muscles. Moreover, HSP72 protein expression in H30x4 group was significantly higher than in H30 group in both EDL and soleus muscles. The HSP72 mRNA was markedly increased from control levels in the H30 and H30x4 group in both types of muscles . However, HSP72 mRNA of the H30x4 group was lower than that of the H30 group in soleus muscles. Heat shock response of HSP72 is activate d even after repeated bouts of hyperthermia, with a differential regulation between muscle types., J. Lee, K. Himori, D. Tatebayashi, M. Abe, T. Yamada., and Obsahuje bibliografii
Conventional radiotherapy with X- and γ-rays is one of the common and effective treatments of cancer. High energy hadrons, i.e., charged particles like protons and 12C ions, due to their specific physics and radiobiological advantages are increasingly used. In this study, effectiveness of different radiation types is evaluated on the radio-resistant human HTB140 melanoma cells. The cells were irradiated with γ-rays, the 62 MeV protons at the Bragg peak and in the middle of the spread-out Bragg peak (SOBP), as well as with the 62 MeV/u 12 C ions. The doses ranged from 2 to 24 Gy. Cell survival and proliferation were assessed 7 days after irradiation, whereas apoptosis was evaluated after 48 h. The acquired results confirmed the high radio-resistance of cells, showing better effectiveness of protons than γ-rays. The best efficiency was obtained with 12C ions due to higher linear energy transfer. All analyzed radiation qualities reduced cell proliferation. The highest proliferation was detected for 12C ions because of their large killing capacity followed by small induction of reparable lesions. This enabled unharmed cells to preserve proliferative activity. Irradiations with protons and 12C ions revealed similar moderate pro-apoptotic ability that is in agreement with the level of cellular radio-resistance., A. Ristić-Fira ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The kinetics of Ig-positive cell populations in carp tissues was followed during an infection with the gut dwelling coc-cidian Goussia carpelli Léger et Stankovich, 1921. In cell suspensions of the anterior and posterior sections of the intestine, the proportion of Ig-positive cells increased with the development of the coccidia and peaked during oocyst formation at day 15 post exposure. These results suggest a reaction of the local mucosal immune system. In cell suspensions of pronephros the proportion of Ig-positive cells increased as well, indicating that a systemic immune response was also induced against this intestinal cocci-dian parasite of carp.
The present study was designed to investigate the ameliorative effect of cyclosporine A (CsA) pretreatment on an anoxia/reoxygenation injury model by using immobilized perfused hepatocytes. Rats received an i.p. injection of two successive doses of CsA (5 mg/kg/day). Twenty-four hours later hepatocytes were isolated from CsA-treated and control rats. After hepatocyte isolation, immobilization, perfusion, induction of anoxia/reoxygenation, the structural and functional integrity of the hepatocytes was followed in a perfusion medium by measuring the leakage of lactate dehydrogenase (LD) and the time course of urea biosynthesis. CsA pretreatment reduced the initial rate of urea synthesis during normoxia but reduced the drop in the relative percentage rate of urea synthesis during the period of anoxia. LD leakage was increased threefold by anoxia and sevenfold by reoxygenation in cells of untreated animals. After CsA pretreatment in vivo, hepatocytes showed no increase in LD leakage into the medium. These findings demonstrate that the perfused immobilized hepatocytes can be used as a cellular model to assess the effects of liver insults such as anoxia/reoxygenation injury and that CsA modulates the injury. The mechanisms of CsA beneficial effects at the experimental level remain to be elucidated.
The effects of tannic acid on mean values and genetic variation in fitness-related traits (mass, relative growth rate) and specific activities of digestive enzymes (total proteases, a-glucosidase and lipase), and genetic variation in their plasticity, were investigated in fifth instar larvae of Lymantria dispar L. (Lepidoptera: Lymantriidae) originating from two populations with different host use histories (oak and locust-tree). The two populations did not differentiate with respect to fitness-related traits, i.e. adverse effects of tannic acid were similar in both populations. However, Robinia larvae, which originated from the locust-tree forest, were characterized by higher total protease and lipase activity and lower a-glucosidase activity than Quercus larvae, which originated from the oak forest. Higher plasticity of lipase and lower plasticity of a-glucosidase in response to tannic acid were also recorded. Quantitative genetic analysis revealed mostly significant expression of genetic variation in the examined traits and trait plasticity, suggesting the potential for evolution of adaptive plastic responses to new environmental conditions and presence of a stressor. The genetic correlations observed between the environments significantly differed from “one”, which indicates there are no constraints on the evolution of trait plasticity., Marija Mrdakovic ... [et al.]., and Obsahuje seznam literatury