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Regenerace smyslových orgánů u raků
KOR, Golara
2024 - English
Anteny jsou u raků důležitým smyslovým orgánem, které mají zásadní roli na jejich přežití, komunikaci a orientaci v prostředí. Jsou vybaveny smyslovými chloupky, které umožňují rakům detekovat různé podněty. Raci mají jedinečnou schopnost regenerovat své anteny. Hemocyty jsou specializované buňky raků a hrají klíčovou roli v jejich imunitním systému a podílejí se na procesu regenerace. Ke studiu morfologie a regenerace smyslových orgánů u raků jsme použili kryo-skenování a transmisní elektronové mikroskopy. V kapitole 2 byla kryo-skenovací elektronová mikroskopie použita k identifikaci potenciálních rozdílů v morfologii anten u šesti různých druhů raků, zahrnujících raka mramorovaného Procambarus virginalis, raka mexického Cambarellus patzcuarensis), raka červeného (Procambarus clarkii), raka signálního (Pacifastacus leniusculus), raka ničivého (Cherax destructor) a raka pruhovaného (Faxonius limosus). Zjistili jsme významné rozdíly mezi šesti druhy raků v poměru délky anteny, délky a šířky segmentu k délce krunýře a počtu segmentů. Zkoumání ultrastrukturálních rysů odhalilo rozdíly ve vzorcích distribuce smyslových chloupků podél anten a morfologii povrchu anten. Rozdílná morfologie anten mezi studovanými druhy pravděpodobně ukazuje na přizpůsobení se specifickým podmínkám jejich příslušných stanovišť. Výsledky dále ukázaly, že kombinace morfologických charakteristik anten nám může pomoci rozlišit různé studované druhy raků. V kapitole 3 bylo pomocí transmisní elektronové mikroskopie zkoumáno ultrastrukturální chování hemocytů během koagulace a fagocytózy v počátečních fázích poranění u raka mramorovaného. Během koagulačního procesu prodělaly hemocyty výrazné transformace v morfologii. Cytoplazmatická granula vykazovala změnu z elektronově hustých na elektronově prostupné formy s postupem koagulace. Bylo pozorováno, že transformované granule obsahují amorfní, pro eletrony prostupný materiál navzájem spojený a uvolňující svůj obsah do extracelulárního prostoru jako součást koagulačního procesu. Kromě toho bylo pozorováno, že obsah jádra také hraje roli během procesu koagulace. Navíc amputace nohy vedla k silné svalové degeneraci a fagocytující hemocyty začaly pohlcovat nekrotické tkáně. Kromě toho jsme pozorovali natrávené zbytky z fagocytovaných nekrotických tkání sloučených do granulí a dalších buněčných složek, čímž se zvýšila granularita hemocytů a změnila se jejich buněčná morfologie. Je však nutno poznamenat, že degranulace hemocytů během koagulace by mohla potenciálně snížit jejich granularitu. Vzhledem k tomu, že morfologické vlastnosti jsou pro klasifikaci hemocytů zcela zásadní, musí být tyto morfologické změny během koagulace a fagocytózy považovány za významné faktory. Degenerovaný materiál uložený uvnitř fagocytárních hemocytů může mít uplatnění v imunologických a regeneračních procesech. V kapitole 4 jsme použili transmisní elektronovou mikroskopii, abychom prozkoumali ultrastrukturální aspekty potenciálního zapojení imunitních buněk do regenerace nervů po amputaci anten raků. Zjištění ukázala, že během regenerace nervů byly přítomny všechny tři formy hemocytů. Nicméně granule v semigranulocytech a granulocytech přispěly především ke vzniku nových organel, jako jsou mitochondrie, Golgiho aparát a nervová vlákna v regenerovaných nervech račích anten. Odhalili jsme transformaci granulí hemocytů na různé organely během procesu regenerace nervů na ultrastrukturální úrovni. Závěrem lze říci, že tyto granule fungují jako kompaktní úložiště adaptabilních materiálů nesených imunitními buňkami, schopných transformace na různé organely během regenerace nervů v račích anten. The antennae are a crucial sensory organ in crayfish that plays vital roles in their survival, communication, and orientation within their environment. They are equipped with sensory hairs that enable crayfish to detect various stimuli. Crayfish possess the unique ability to regenerate their antennae. Hemocytes are specialized cells within crayfish and play a crucial role in their immune system and contribute to the process of regeneration. We applied cryo-scanning and Transmission electron microscopies to study sensory organ morphology and regeneration in crayfish. In Chapter 2, cryo-scanning electron microscopy was used to identify potential differences in antennal morphology in six different crayfish species including marbled crayfish Procambarus virginalis, Mexican dwarf crayfish Cambarellus patzcuarensis, red swamp crayfish Procambarus clarkii, signal crayfish Pacifastacus leniusculus, common yabby Cherax destructor, and spiny-cheek crayfish Faxonius limosus. We observed significant differences among the six crayfish species in the ratios of antenna length, segment length and width to carapace length, and the number of segments. Examination of ultrastructural features unveiled differences in the distribution patterns of sensory hairs along the antenna and the morphology of the antennal surface. The varying morphology of antennae among studied species possibly indicates an adaptation to the specific conditions of their respective habitats. Furthermore, the outcomes demonstrated that a combination of variations in both antennal morphological characteristics and biometric measurements could effectively help us to distinguish the different studied crayfish species. In Chapter 3, the ultrastructural behaviour of hemocytes during coagulation and phagocytosis in the initial phases of injury in marbled crayfish was explored using transmission electron microscopy. During the coagulation process, hemocytes experienced marked transformations in morphology. The cytoplasmic granules exhibited a change from electron-dense to electron-lucent forms with the progress of coagulation. The transformed granules containing amorphous, electron-lucent material were observed to combine and release their contents into the extracellular space as part of the coagulation process. Additionally, it was observed that the nucleus contents also play a role in the coagulation process. Furthermore, the amputation of the leg led to substantial muscle degeneration, and phagocytic hemocytes start to take up the necrotic tissues. Besides, we observed the digested remains from phagocytized necrotic tissues merged into granules and other cellular components, thereby enhancing the granularity of the hemocytes and altering their cellular morphology. However, it is essential to note that hemocyte degranulation during coagulation could potentially reduce their granularity. Since morphological features are critical for classifying hemocytes, these morphological changes during coagulation and phagocytosis must be considered significant factors. The degenerated material that stored inside phagocytic hemocytes may have application in immunological and regeneration processes. In Chapter 4, we employed transmission electron microscopy to explore the ultrastructural aspects of potential immune cell involvement in nerve regeneration within crayfish antennae post-amputation. The findings indicated that, during nerve regeneration, all three forms of hemocytes were present. However, the granules within semi-granulocytes and granulocytes mainly contributed to the generation of new organelles such as mitochondria, the Golgi apparatus, and nerve fibers in the regenerated nerves of crayfish antennae. We revealed the transformation of granules of hemocytes into diverse organelles during the process of nerve regeneration at the ultrastructural level. In conclusion, these granules function as compact repositories of adaptable materials carried by immune cells, capable of transformatio Keywords: Anteny; Elektronová mikroskopie; Hemocyt; Imunitní systém; Regenerace Available in the Digital Repository of University of South Bohemia.
Regenerace smyslových orgánů u raků

Anteny jsou u raků důležitým smyslovým orgánem, které mají zásadní roli na jejich přežití, komunikaci a orientaci v prostředí. Jsou vybaveny smyslovými chloupky, které umožňují rakům detekovat různé ...

KOR, Golara
Jihočeská univerzita v Českých Budějovicích, 2024

The study of the phylogeny and taxonomy of selected genera of Erebidae (Lepidoptera; Noctuoidea) as a tool for understanding of origin of the Afrotropical moth fauna
IGNATEV, Nikolai
2024 - English
In this thesis, I conducted the taxonomical and phylogenetical research of selected Afrotropical moth genera, especially an Old-World moth genus Amerila, Walker 1855. All the studied genera belong to the family Erebidae (Lepidoptera; Noctuoidea) and are well-presented in the state European entomological collections. In our research, we used mitochondrial, or mitochondrial and nuclear markers and different molecular analyses to resolve relationships within the studied genera (exclude Meganaclia, Aurivillius 1892). Comparative morphological analysis was used in all the studies. We aimed to update the classification of studied Lepidoptera genera, and to highlight the gaps in taxonomical study of Afrotropical moth fauna in general. Keywords: arctiinae; ancestral state reconstruction; integrative taxonomy; morphological characters Available in the Digital Repository of University of South Bohemia.
The study of the phylogeny and taxonomy of selected genera of Erebidae (Lepidoptera; Noctuoidea) as a tool for understanding of origin of the Afrotropical moth fauna

In this thesis, I conducted the taxonomical and phylogenetical research of selected Afrotropical moth genera, especially an Old-World moth genus Amerila, Walker 1855. All the studied genera belong to ...

IGNATEV, Nikolai
Jihočeská univerzita v Českých Budějovicích, 2024

Investigating associations of saproxylic beetles with forest structure through the analysis of species composition and feeding guilds
KOZEL, Petr
2024 - English
The thesis contains studies focusing on various forest biotopes of Central Europe and saproxylic beetles as a model group for forest ecology research. In the review, current knowledge about the threats for forest biota, mainly saproxylic beetles are discussed in the context of species composition and trait-based approach. Various stages of succession in the patches of disturbed forests, their connectivity, the introduction non-native tree species, and the assessment of feeding guilds using stable isotopes are studied in the relation to saproxylic beetles in separate chapters. Keywords: connectivity; forest ecology; non-native tree species; trait-based approach; saproxylic beetles; species composition; stable isotopes; succession Available in the Digital Repository of University of South Bohemia.
Investigating associations of saproxylic beetles with forest structure through the analysis of species composition and feeding guilds

The thesis contains studies focusing on various forest biotopes of Central Europe and saproxylic beetles as a model group for forest ecology research. In the review, current knowledge about the ...

KOZEL, Petr
Jihočeská univerzita v Českých Budějovicích, 2024

Anthropogenic impact on early-life stages of rheophilic fish
BARTOŇ, Daniel
2024 - English
This study focuses on the problems faced by the early-life stages of fish living in a river influenced by reservoirs and suggests possible solutions to enhance recruitment. The model fish for the study is the asp (Leuciscus aspius), known for its significant and protected population in the Želivka Reservoir, from where it migrates for reproduction to the tributary of Želivka River. The asp migrates upstream in spring to spawn in shallow, fast-flowing waters. At a research site, the adult population of asp is monitored using passive telemetry. Fish are caught, tagged, and released back into the reservoir. The asp population faces threats due to hydropeaking and river fragmentation. Hydropeaking causes egg detachment from the pebbles and their sedimentation in the reservoir. The study suggests that water should not exceed a velocity of 0.7 m×s-1 at the spawning ground. Periodically increasing discharge also shifts spawning fish outside their preferred spawning site, causing disruption of spawning and potentially lowering recruitment. A flowdeflector was built to protect newly spawned eggs from hydropeaking. However, there are additional threats to the asp recruitment process such as egg consumption by non-indigenous fish like common bream (Abramis brama). Water flow conditions are crucial for the conservation of rheophilic fish, as these fish, aside from habitat loss and modification, also face newly interacting generalist fish species moving from lentic to lotic sections of the system. Fish communities can be affected by reservoir construction far upstream, and these anthropogenic habitat alterations have severe negative impacts on threatened rheophilic fish recruitment. This study focuses on the problems faced by the early-life stages of fish living in a river influenced by reservoirs and suggests possible solutions to enhance recruitment. The model fish for the study is the asp (Leuciscus aspius), known for its significant and protected population in the Želivka Reservoir, from where it migrates for reproduction to the tributary of Želivka River. The asp migrates upstream in spring to spawn in shallow, fast-flowing waters. At a research site, the adult population of asp is monitored using passive telemetry. Fish are caught, tagged, and released back into the reservoir. The asp population faces threats due to hydropeaking and river fragmentation. Hydropeaking causes egg detachment from the pebbles and their sedimentation in the reservoir. The study suggests that water should not exceed a velocity of 0.7 m×s-1 at the spawning ground. Periodically increasing discharge also shifts spawning fish outside their preferred spawning site, causing disruption of spawning and potentially lowering recruitment. A flowdeflector was built to protect newly spawned eggs from hydropeaking. However, there are additional threats to the asp recruitment process such as egg consumption by non-indigenous fish like common bream (Abramis brama). Water flow conditions are crucial for the conservation of rheophilic fish, as these fish, aside from habitat loss and modification, also face newly interacting generalist fish species moving from lentic to lotic sections of the system. Fish communities can be affected by reservoir construction far upstream, and these anthropogenic habitat alterations have severe negative impacts on threatened rheophilic fish recruitment. Available in the Digital Repository of University of South Bohemia.
Anthropogenic impact on early-life stages of rheophilic fish

This study focuses on the problems faced by the early-life stages of fish living in a river influenced by reservoirs and suggests possible solutions to enhance recruitment. The model fish for the ...

BARTOŇ, Daniel
Jihočeská univerzita v Českých Budějovicích, 2024

A novel structurally characterized haloacid dehalogenase superfamily phosphatase from Thermococcus thioreducens with diverse substrate specificity
HAVLÍČKOVÁ, Petra
2024 - English
This RNDr. thesis is focused on complex studies of a haloacid dehalogenase superfamily phosphatase member with an unknown substrate specificity, isolated from a hyperthermofilic archeon Thermococcus thioreducens. The HAD phosphatase, internally named as Tt82, was isolated, expressed and purified using standard techniques and the crystal structure was solved by X-ray crystallography method. The refined crystal structure displayed characteristic HAD superfamily elements, such as the HAD canonical fold with the HAD signature motifs in the active site. Further, possible substrates for the enzyme were proposed and examined by computational docking in the active site of the HAD phosphatase. The results of the docking studies served as a basis for an experimental measurement of Tt82 enzymatic activity against selected substrates at two different temperatures. HAD phosphatase Tt82 is a promising target for the biotechnological field, mainly for its wide substrate specificity and higher temperature optima. Available in the Digital Repository of University of South Bohemia.
A novel structurally characterized haloacid dehalogenase superfamily phosphatase from Thermococcus thioreducens with diverse substrate specificity

This RNDr. thesis is focused on complex studies of a haloacid dehalogenase superfamily phosphatase member with an unknown substrate specificity, isolated from a hyperthermofilic archeon Thermococcus ...

HAVLÍČKOVÁ, Petra
Jihočeská univerzita v Českých Budějovicích, 2024

Functional Ultrastructure of Hymenopteran Stingers: Devastating Spear or Delicate Syringe
ČERNÝ, Jan
2024 - English
In this study, we tested the hypothesis that a micro-serrated edge on the honey bee Apis mellifera stinger tip serves as a tool for more intensive crushing of cell membranes in the victim's tissues. This could have mechanical consequences as well as initiate metabolic pathways linked to cell membrane breakdown (e.g., production of biogenic amines). Accordingly, we found that hymenopteran species that use their stingers as an offensive or defensive weapon to do as much damage to the victim's body as possible had this cuticular microstructure. In parasitic hymenopterans, on the other hand, this structure was missing, as stingers are solely used to delicately transport venom to the victim's body in order to do little mechanical harm. We also demonstrated that the stinger lancets of the honey bee A. mellifera are living organs with sensilla innervated by sensory neurons and containing other essential tissues, rather than mere cuticular structures. Keywords: bee; Hymenoptera; nerve; SEM; sensilla; stinger microstructure; TEM; ultrastructure Available in the Digital Repository of University of South Bohemia.
Functional Ultrastructure of Hymenopteran Stingers: Devastating Spear or Delicate Syringe

In this study, we tested the hypothesis that a micro-serrated edge on the honey bee Apis mellifera stinger tip serves as a tool for more intensive crushing of cell membranes in the victim's tissues. ...

ČERNÝ, Jan
Jihočeská univerzita v Českých Budějovicích, 2024

Functional characterization of the insulin signaling pathway in the hard tick Ixodes ricinus
KOZELKOVÁ, Tereza
2024 - English
In this thesis, the molecular and functional characterization of the insulin receptor signaling pathway (ISP) in hard tick Ixodes ricinus was characterized. As obligatory blood-feeding ectoparasites, ticks play a crucial role in the transmission of various pathogens, including bacteria, viruses, and protozoa, which has a significant impact on human and animal health. The parasite is strictly bonded with its host through a unidirectional transmission of nutrition for its survival, development, and reproduction. The ISP, a highly conserved system, regulates numerous physiological and anabolic processes to nutritional availability. This study aims to investigate the functionality of key components of the ISP pathway identified in the midgut transcriptome, namely the insulin receptor (IrInR), the protein kinase B called AKT (IrAKT), and the target of rapamycin (IrTOR). To achieve this goal, the expression profiles of these components in tick tissues during feeding and after detachment were investigated using qRT-PCR. Additionally, RNAi silencing of individual components was performed, and the phenotype of the ticks was observed. To further clarify the effects of ISP, immunization of rabbits with recombinant IrInR protein and tick infestation were investigated. Available in the Digital Repository of University of South Bohemia.
Functional characterization of the insulin signaling pathway in the hard tick Ixodes ricinus

In this thesis, the molecular and functional characterization of the insulin receptor signaling pathway (ISP) in hard tick Ixodes ricinus was characterized. As obligatory blood-feeding ...

KOZELKOVÁ, Tereza
Jihočeská univerzita v Českých Budějovicích, 2024

Oligomerization state and pigment contents of algal light-harvesting proteins
MALINOVÁ, Kateřina
2023 - English
Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus minutus) were studied. LHCs were extracted and purified using sucrose gradient ultracentrifugation and ion-exchange chromatography. Oligomerization states of LHCs were assessed using two independent methods - CN-PAGE and size-exclusion chromatography. Effects of the purification on LHC pigment composition was assessed using HPLC. Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus minutus) were studied. LHCs were extracted and purified using sucrose gradient ultracentrifugation and ion-exchange chromatography. Oligomerization states of LHCs were assessed using two independent methods - CN-PAGE and size-exclusion chromatography. Effects of the purification on LHC pigment composition was assessed using HPLC. Keywords: pigments; LHC; HPLC; alga; SEC; IEC Available in the Digital Repository of University of South Bohemia.
Oligomerization state and pigment contents of algal light-harvesting proteins

Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus ...

MALINOVÁ, Kateřina
Jihočeská univerzita v Českých Budějovicích, 2023

Evolúcia socio-kultúrnych adaptací člověka: Fylogenetická medzi-kultúrna perspektíva
ŠAFFA, Gabriel
2023 - English
This thesis investigates the adaptive significance of seemingly maladaptive human behaviors or cultural norms that are often viewed as responses to intra- and inter-sexual conflict. It combines behavioral ecological approach with phylogenetic comparative methods to study evolutionary origins and maintenance of these practices, using samples of ethnographically documented human societies. The thesis is divided into three sections. The first section is the introduction to evolutionary sciences of human behavior, including an overview of the theoretical perspectives and a critical evaluation of the methodological approaches to macro-evolutionary studies of human behavior and culture. The second section consists of three chapters - two published research papers and a manuscript that is currently under review. The first paper investigates female and male genital mutilation/cutting practices, their evolutionary history, and socio-ecological correlates; the second paper investigates restrictions on female premarital sex and evaluates the three hypotheses explaining them - male, female, and parental control hypothesis; the third paper investigates the causes of socially imposed monogamy and evaluates the competing hypotheses explaining its prevalence in stratified, agricultural societies. The last section summarizes the results of the three studies and concludes with perspectives of future research. Keywords: adaptation; causal inference; cultural evolution; human behavioral ecology; phylogenetics; regression Available in the Digital Repository of University of South Bohemia.
Evolúcia socio-kultúrnych adaptací člověka: Fylogenetická medzi-kultúrna perspektíva

This thesis investigates the adaptive significance of seemingly maladaptive human behaviors or cultural norms that are often viewed as responses to intra- and inter-sexual conflict. It combines ...

ŠAFFA, Gabriel
Jihočeská univerzita v Českých Budějovicích, 2023

Environmental and socio-cultural determinants of language skills and ethnobiological knowledge in Papua New Guinea and Cameroon
KIK, Alfred
2023 - English
Available in the Digital Repository of University of South Bohemia.
Environmental and socio-cultural determinants of language skills and ethnobiological knowledge in Papua New Guinea and Cameroon

KIK, Alfred
Jihočeská univerzita v Českých Budějovicích, 2023

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