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Induction and optimalization out-of-season spawning of spawners pikeperch (Sander lucioperca)
VLČEK, Jakub
In total, 21 pairs of pikeperch brood stock were divided into three groups and used during two out-of-season and one seasonal semi-artificial spawning. The only differences among these three groups were the length of cold water period (CWP) and spawning date. Group of earlier spawning (A) CWP = 122 days, Group of normal spawning (B) CWP = 149 days, Group of late spawning (C) CWP = 223 days). Dates of spawnings A 11.3., B 26.4., C 13.6). There were observed and assessed the main production parameters such us latency, successful spawning, fertilisation and hatching rate etc. in each group and spermatozoa quality (sampled one day after the observed spawning). In Group A and B, 100 % of fish successfully spawned. Fertilisation rate was 59.4 % (Group A) and 80.3 % (Group B). Much worse results were obtained in Group C. Only 42.9 % of fish spawned and the fertilisation rate was zero. There was no difference among the three groups in spermatozoa quality parameters. It means that the poor fertilisation rate in Group C was caused by low egg quality. According to our results we can say that it is possible to successfully spawn pikeperch earlier (before the main spawning season) with comparable result to the natural spawning season. However, it is necessary to find some better way for female stimulation to provide higher egg quality and subsequently higher fertilisation rate.
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The role of caspase 2 in apoptosis induction in tumor cells.
Schmiedlová, Martina ; Horníková, Lenka (referee) ; Kovář, Jan (advisor)
Within the cell, caspase-2 probably fulfills several functions. Caspase-2 can be involved in apoptosis induction, DNA repair as well as cell cycle regulation. Caspase-2 has the character of initiator and also executioner caspase. A stimulus for caspase 2 activation can be oxidative stress or DNA damage. Caspase-2 is activated by cleavadge during an interaction with protein complexes. One of protein complexes,i.e. PIDDosome, is made of protein PIDD, RAIDD and pro-caspase-2. Withine the PIDDosome, caspase-2 is activated. Activated caspase-2 occures in a short S form and in long L form. L form of caspase-2 has proapoptotic effects and S form of caspase-2 has antiapoptotic effects. Caspase-2S has been only detected on mRNA level but not on protein level. The main role of caspase-2L is apoptosis induction in normal and tumor cells. Caspase-2 in tumour cells is activated by extrinstic as well as intristic apoptotic pathway. Apoptosis induction by caspase-2 is for example studied in connection with breast cancer treatment with taxanes. Caspase-2 ability of apoptosis induction in cancer cells independently of p53 protein is employed in cancer treatment including overcoming the resistance to apoptosis induction which is based on loosing p53 activity. Caspase-2 is involved in apoptosis induction by different...
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Defence mechanisms of sugarbeet participating on resistance against pathogens and pests
Grigová, Vendula ; Burketová, Lenka
The plants dispose their own defence mechanisms against pathogen attack, which include both constitutive and induced structural changes, but mainly biochemical changes. SAR (Systemic Acquired Resistance) is an important defence mechanism. The objective was to compare defence reactions of sugar beet against the causal agent of rhizomania, i.e. BNYVV and its vector Polymyxa betae, with sugar beet reaction after soil nematode attack and with reaction to treatment with chemical and biological inductors of resistance. We have shown that the same spectrum of hydrolytic PR-proteins (basic -1,3-glucanase (Glu2), basic class IV chitinase (Ch4), acidic class III chitinase (SE2), basic class II chitinase (Ch2)) is induced both after pathogen/pest attack and after BTH inductor treatment; nevertheless, the intensity of induction is related to a particular agent. Increased accumulation of glucanase was detected immunohistologically in sugar beet tissues both after pathogen/pest attack and after BTH inductor treatment.
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Hormonal induction of ovulation in whitebarred catfish (Agamyxis pectinifrons)
KNOWLES, Jindřiška
The aims of presented work are reviewing of current knowledge about biology and artifical reproduction, evaluation of dopamine inhibition of LH secretion and identification of optimal hormonal treatment of ovulation in tropical whitebarred catfish. Two trials were conducted in years 2012 and 2013. The experiments differed from each other only in the water temperature 29,5 °C (Experiment No.1) and 26 °C (Experiment No.2). In each experiment, the fish were divided into 4 groups. Group A was injected only with mGnRHa, group B was injected with dopamine inhibitor metoclopramide, group C was injected with mGnRHa plus metoclopramide and group D was injected only with physiological saline (0,9 % NaCl). Ovulation occurred only in the groups injected with the combination of GnRHa and dopamine inhibitor, however in both experiments. In Experiment No.1, the ovulation rate was around 60%, relative fecundity was 331,025 +- 47,508 eggs . kg-1, latency interval was at 10.3 +- 0.6 hours and the fecundity index was determined at 13, 8. In Experiment No. 2 ovulation, the level of ovulation was 50%, relative fecundity was 408,561 +- 34,934 pieces of eggs . kg-1, latency interval was 13.7 +- 0.7 hours and fecundity index was 15.35. The results clearly show a strong inhibition of dopamine on LH secretion and show that the combination of GnRHa with dopamine inhibitor can be successfully used to induce ovulation in whitebarred catfish.
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Measurement the induction of magnetic field around an applicator for magnetotherapy
Bartušek, Karel ; Gescheidtová, E. ; Steinbauer, M.
The paper deals with measuring magnetic induction by imaging techniques based on magnetic resonance (MR) and describes experimental results od mapping the magnetic induction of a dermatological applicator for magnetotherapy performed by MR imaging techniques. The results are compared with theoretical calculation and with measurement carried out with an ordinary magnetometr. The conclusion derived from the measurement will be used in the design of a new applicator with complex electronic control of magnetic field.
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Induction of suppressive soil by introduction of mycoparasitic fungi against important plant pathogens
STREJČKOVÁ, Monika
This M. Sc. thesis is based on using of mycoparasitic fungi Trichoderma virens, Clonostachys rosea f. catenulata in biological control against phytopathogenic fungi Sclerotinia sclerotiorum, Rhizoctonia solani, Botrytis cinerea and Fusarium solani. The efficacy of mycoparasitic fungi against pathogens was evaluated in dual cultural tests. The strains of T. virens and C. rosea f. catenulata isolated from soils in the Czech Republic were tested in the experiment. Reference strain was GL 21 fungus T. virens reisolated from commercially available bio-preparation SoilGard and strain C. rosea f. catenulata reisolated from Prestop Mix. All the strains were tested for biological and production properties. All strains are able to colonize the substrate and to suppress the growth and development of pathogens. Strain GL 21 of T. virens was used for seed coating of variety Scirocco in combination with products Guar gum and Carboxymethyl cellulose, which served as a carrier for stick on conidia. After 3 days, the effect of fungus T. virens was evaluated on energy of germination, development of roots of grain. The grain health was determined after 7 days. The fungus T. virens has a positive effect on the grains germination and grain health. During the vegetation the influence of seed coating by T. virens was observed on growth and development of spring wheat. The parameters such as number of plants per m2, tiller numbers, plants health, stand height, number of grains in the spike and thousand grain weight (TGW) were evaluated. During the vegetation the fungus T. virens has positive effect on the plant height.
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