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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Rozdíly v aktivitě spermií hřebců

NOVOTNÁ, Lucie January 2019 (has links)
One of the requirements for a successful artificial insemination is the quality of stallion´s ejaculate. This thesis deals with influence of sperm velocity fraction on fertility. Semen samples in this thesis were evaluated by using an objective computerized method CASA, system SCA. Sperm motility in monitoring was performed in 75 samples from 12 stallions involved in artificial insemination fresh sperm in ZH Písek. Total and progressive motility, rapid, medium and slow motility were monitored. Stallion´s age was from 3-21 years. The average of fertility was 56,19 %. The average of total motility was 78,07 %. The average of progressive motility was 38,35 %. Furthermore, the spermatozoa were divided into 3 velocity fractions and the average percentage of the individual fractions in the samples was as follows: 27,30 % rapid spermatozoa, 21,27 % medium spermatozoa and 29,50% slow spermatozoa. Then the average percentage of rapid progressive spermatozoa (13,43 %), medium progressive spermatozoa (24,92 %) and non-progressive spermatozoa (39,72 %) were found. There was a positive correlation between fertility and the rate of rapid motile spermatozoa (r=0,34). The difference between individual stallions (p-value < 0,01) in the mean percentage of rapid spermatozoa in the ejaculate was demonstrated. The stallion with the highest rate of rapid motile spermatozoa and the best pregnancy was welsh part-bred stallion. On the other hand, the worst pregnancy results and one of the lowest percentages of rapid motile spermatozoa had noriker stallion. The highest success rate of pregnancy was found after the second insemination.The results of this work have shown that the quality of the ejaculate has a very significant effect on good pregnancy but it is just one of many acting factors.
2

Vliv aditivních látek na funkční vlastnosti kančích spermií

Lipenský, Jan January 2018 (has links)
The aim of this study was to evaluate the preservation ability of five commercial boar semen extenders and compare CASA (Computer Assisted Sperm Analysis) method and classic subjective method of the sperm motility evaluation. The second objective of this study was to examine the boar seminal plasma selenium and zinc concentration and their relation to semen quality and quantity. The third objective of this study was to analyse the effect of twelve natural substances characterized by antibacterial activity on boar semen. Furthermore, the last objective of this study was to assess the effect of herbal extract supplement prepared from Eurycoma longifolia, Tribulus terrestris and Leuzea carthamoides on libido, semen quality and quantity in boars. The sperm progressive motility decreased among all tested extenders, depending on the storage time and increasing dilution ratio. The highest sperm progressive motility was achieved in Androhep Plus extender, followed by extenders VIP 5 and VIP 3. The lowest progressive sperm motility was typical for both BTS type extenders. The sperm progressive motility was influenced by the method and by the method and interactions with a variety of other factors including dilution ratio, sample storage time and sperm movement quality. There was no significant relation between the boar seminal plasma zinc concentration and sperm quality or quantity parameters. The boar seminal plasma selenium concentration positively correlated with sperm progressive motility, sperm concentration, total number of spermatozoa per ejaculate and negatively with distal protoplasmic droplet occurrence. Natural substances characterized by antibacterial activity had a significant negative effect on the sperm progressive motility. The positive effect of the herbal extract supplement containing natural stimulants on the libido of boars has been demonstrated in this study. The quality or quantity of boar sperm was not highly affected by this herbal extract supplement.
3

Uloha kataninu, ATPázy štěpící mikrotubuly, při modulaci buněčné motility a proliferace glioblastomových buněk. / Uloha kataninu, ATPázy štěpící mikrotubuly, při modulaci buněčné motility a proliferace glioblastomových buněk.

Uhlířová, Jana January 2016 (has links)
Glioblastomas are the most common and the deadliest types of brain tumours. Due to their highly invasive behaviour, they are incurable by convencial therapeutical strategies. It was shown that some components of microtubules, namely class III β-tubulin, γ-tubulin and microtubule severing protein spastin are overexpressed in glioblastoma cell lines as well as glioblastomas. This diploma thesis is focused on the expression, subcellular distribution and function of katanin, another microtubule-severing enzyme, in gliobastoma cell lines. Katanin is formed by catalytic (p60) and regulatory (p80) subunits. Expression and cellular localization of both katanin subunits was studied in panel of human glioblastoma cell lines isolated form adults (T98G, U87MG, U118MG and U138 MG) and child (KNS42). Data presented in this thesis demonstrated that katanin subunits were overexpresed both on transcript and protein levels in T98G, U87MG and KNS42 cell lines, but not in U138MG and U118MG cell lines when compared to normal non- transformed human astrocytes. Immunofluorescence microscopy revealed that both katanin subunits were diffusively distributed in cytoplasm and concentrated on spindle poles of mitotic cells and on leading edges of migrating cells. Examination of cell motility revealed that velocities in...
4

Kryokonzervace spermií kapra obecného (Cyprinus carpio) při různých podmínkách zmrazování. / Cryopreservation of common carp (\kur{Cyprinus carpio} L.) sperm under different freezing conditions

SOCHOROVÁ, Denisa January 2015 (has links)
In the present study, we examined several cryoextenders previously used by several authors and various freezing protocols to determine the relative importance of each parameter on sperm freezing. The effects of controlled seeding and changes in cooling rate at different stages of freezing were also examined. Sperm samples from seven individual carp males were frozen in 0.5 ml straws by conventional freezing. Cooling rates were determined by monitoring the sample's internal temperature. We compared four freezing protocols, which involved placing sperm samples at various levels (1, 3, 6, and 9 cm) above the liquid nitrogen (LN) surface (corresponding to -190, -150, -110, and -70 °C, respectively) for 20 min followed by transferring the samples into LN. Freezing at 3 cm above the LN surface resulted in the highest motility (33 ? 8 %) and velocity (118 ? 9 ?m/s) of spermatozoa after thawing and diluting in swimming medium. We determined that -90 °C is an optimal temperature at which immersing the samples in LN does not affect sperm motility after thawing. The sperm motility of samples immersed in LN before or immediately after the crystallisation point (-16 °C) was 0 %. Motility of spermatozoa cryopreserved with or without a seeding procedure was not significantly different after thawing. Therefore, we hypothesise that supercooling the sample during the conventional freezing procedure is not the main damaging factor during carp spermatozoa cryopreservation.
5

Analysis of the role of PilA proteins in the cyanobacterium \kur{Synechocystis} sp. PCC 6803. / Analysis of the role of PilA proteins in the cyanobacterium \kur{Synechocystis} sp. PCC 6803.

LINHARTOVÁ, Markéta January 2009 (has links)
The PilA proteins are major components of pili fibres which are essential for motility in bacteria. This project was focused on the role of the PilA proteins in cyanobacteria, specifically in the alternative functions that are not directly related to motility. The major task of this project was also to develop a method for the purification of the PilA1 protein from Synechocystis under native conditions and to analyze purified PilA1 protein in detail.
6

Motilita spermií a postkopulační prezygotická bariéra u dvou druhů slavíků / Sperm motility and postmating prezygotic isolation in two nightingale species

Baránková, Lucie January 2020 (has links)
The motility of male gametes (sperm) is one of the important factors influencing the reproductive success of males. Because sperms are often subjected to strong postmating sexual selection and even closely related species often differ in sperm morphology, sperm motility could also differ between species, which may contribute to reproductive isolation between species. As part of my diploma thesis, I studied sperm motility in two closely related species of songbirds, the common nightingale (Luscinia megarhynchos) and the thrush nightingale (Luscinia luscinia). These two species of nightingales are an ideal model system because the areas of these two species overlap in the secondary contact zone across Central and Eastern Europe, where they occasionally hybridize and thus allow the study of speciation mechanisms in the natural environment. Both species also differ greatly in total sperm length. As part of my diploma thesis, I studied the possible influence of different sperm morphology on their motility. I further tested whether the motility of nightingale sperm differs in the fluid from the cloaca of a female of the same species and a different species, which would demonstrate the presence of postmating prezygotic reproductive isolation between species. The results of my work showed that despite the...
7

Studium vlivu genu yxkO Bacillus subtilis na motilitu během odpovědi na osmotický stres. / Study of effect of Bacillus subtilis yxkO gene on motility during stress response to osmotic upshift.

Streitová, Eliška January 2010 (has links)
Bacillus subtilis is gram-positive soil bacteria. In its natural environment it is constantly exposed to changes of chemical and physical conditons, including changes of osmolality. It responds to high osmolality by transporting of potassium ions and afterthat transporting and/or synthetising of compatible solutes. In last years the mutant strain Bacillus subtilis L-42 was isolated with non-specific insertional mutagenesis (mini Tn10) in our laboratory. This strain displays limited growth and inability to cope with hyperosmotic shock in a defined medium with potassium concentration of < 1 mmol/l. Insertion of transposon was located in yxkO gene which encodes a protein of unknown biological function. Some other data also indicate a possible role of disruption of yxkO gene in regulation of expression of hag gene, which encodes flagelin - a pivotal protein of bacterial flagellum. The goal of this thesis was to clarify if the disruption of yxkO gene influences motility and whether is affected the transcription of hag gene. With integrative vector pMUTIN4 a mutant strain with specific mutation of yxkO gene was prepared. Vector was pasted into chromosome of Bacillus subtilis strain 1A839 - genotype of this strain allows to extrude the known transcriptional regulation of hag gene. Cell's motility was...
8

Druhotné ornamenty samců a fenotyp spermií u vlaštovky obecné / Secondary male ornamentation and sperm phenotype in barn swallows

Soudková, Martina January 2011 (has links)
No description available.
9

Vliv vyřazení genu yxkO při adaptaci na enviromentální stres u rodu Bacillus. / Effect of knock out of yxkO gene on environmental stress adaptation in genus Bacillus

Tkadlec, Jan January 2011 (has links)
We have previously characterized a Bacillus subtilis mutant defective in growth and osmoadaptation under limited K+ concentrations. In this mutant, the yxkO gene encoding a putative ribokinase is disrupted. This gene is supposed to belong to the sigma B operon and its expression is induced after osmotic, heat and ethanol shock. In comparison to the wild type, this mutation causes pleiotropic changes in host phenotype. In addition to its osmosensitivity, the mutant differs in cell shape, motility and ability to produce endospores. Our goal was to focus on manifestations of the mutation in the yxkO gene in other bacteria of the genus Bacillus. Using plasmid pMUTIN4 we have prepared mutants with disruptions of this gene derived from Bacillus amyloliquefaciens and Bacillus subtilis subsp. spizizenii strains differing in the yxkO surroundings and in the level of laboratory domestication. As in the previous study (with laboratory strain Bacillus subtilis 168) we demonstrate impaired ability of the mutant strain derived from Bacillus amyloliquefaciens to grow in potassium limitation and osmotic shock. We have studied this phenomenon at the level of the growth dynamics of the bacterial culture. We have also detected an increased sensitivity of the strain derived from Bacillus amyloliquefaciens to...
10

Demembranace spermií ryb: navržení a ověření postupů u různých druhů sladkovodních ryb a demonstrace využití této techniky na příkladu studia vlivu těžkých kovů přímo na axonemu spermie / Demembranation of fish sperm: Design and verification this procedure for the different species of freshwaterfish and demonstration usage of this technique by study the effect of heavy metals to sperm axoneme

BLAŽKOVÁ, Jaroslava January 2014 (has links)
The object of this study is to design demembranation method on four freshwater species and its application on study of the influence of HgCl2 on the axoneme and motity sperm motility parameters. Demembranation was designed and examined for all investigated species common carp (Cyprinus carpio), sterlet (Acipenser ruthenus), perch (Perca fluviatilis) and african catfish (Clarias gariepinus). One-step and two-step method was designed and tested for common carp. One-step method was designed for sterlet and perch. Two-step method of demembranation was designed for african catfish. Demembranation was designed and examined for all species under examination. Sperm motility was evidently increased above normal physiological value. Other sperm motility parameters (velocity, percent of motile cells) slightly decreased. HgCl2 in concentration 0,01 mM to the demembranation medium didn't show effect on flagellar microtubule aparat and then to the motility parameters, except sterlet; demembranated sterlet sperm was inhibited at all used concentration of HgCl2. Concentration 0,1 mM had inhibition effect on carp and africant catfish spermatozoa. Concentration 1 mM HgCl2 inhibited sperm of all tested species.

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