Rigorous theses

Rigorous theses 15,322 records found  previous11 - 20nextend  jump to record: Search took 0.00 seconds. 
The evaluation of the effect of PAMAM dendrimers in the solubility of lmiquimod
Micková, Thu Thao ; Paraskevopoulos, Georgios (advisor) ; Paraskevopoulou, Anna (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Supervisor: Dr. Georgios Paraskevopoulos, Ph.D. Consultant: Eleni Panoutsopoulou Author: Mgr. Thu Thao Truongová Title of the thesis: The evaluation of the effect of PAMAM dendrimers in the solubility of Imiquimod Dendrimers are highly branched polymeric compounds with defined properties. They are used as a nanoparticle delivery system, however concurrently they have significant potential in enhancing the solubility of poorly water soluble drugs. Dendrimers work as drug carriers either by encapsulating the drug in their branched internal structure or they create interactions with the drug in the outer layer via terminal functional groups. The aim of this work was to evaluate the effect of polyamidoamine (PAMAM) dendrimers on the solubility of the hydrophobic drug imiquimod. Solutions of zero, first, second and third generation dendrimers were prepared at six different concentrations. During the experiment, the pH of the solutions was measured before and after addition of excess amount of imiquimod. Subsequently, analysis was performed by high-performance liquid chromatography. The measured results show that the first generation of PAMAM dendrimers is able to increase the solubility of imiquimod in...
Synthesis, processing and properties of high-temperature ceramic oxygen conductors
Alemayehu, Adam
Ceramic oxygen conductors are important materials used as solid electrolytes in solid oxide fuel cells and oxygen sensors. Among the many electrolyte materials, cerium dioxide is attracting a lot of attention. This is mainly due to ceria's lower operating temperature than the widely used yttria-stabilized zirconia. Moreover, the doping of cerium dioxide with other lanthanide ions is easily carried out and the final material is stable due to the similar properties of different lanthanides. The most common doping element for cerium dioxide is gadolinium. In this thesis, a study of the precipitation of cerium and gadolinium with oxalic acid was studied focusing especially on the homogeneity of the final oxalate precipitate. The thermal decomposition of the oxalates into oxides and the homogeneity of the final oxide materials were studied. Additionally, large crystals of lanthanide oxalates were obtained by homogeneous precipitation using oxamic acid. The consolidation of the prepared oxides via ultrafast high- temperature sintering was compared with the conventional furnace sintering and the effect of electric fields on grain growth of CeO2 nanocrystalls was described. Key words: ceramic materials, oxygen conductors, oxalates, cerium dioxide, sintering, field- assisted sintering
Study and Evaluation of Topically Applied Ceramides onto Disrupted Skin Barrier
Svobodová, Marie ; Kováčik, Andrej (advisor) ; Vraníková, Barbora (referee)
Department of Pharmaceutical Technology Author: M S b S , Ph.D. Title of diploma thesis: Study and Evaluation of Topically Applied Ceramides onto Disrupted Skin Barrier Skin is the largest organ of the human body and serves several key functions, such as protection against external influences and regulation of body temperature. Healthy skin is able to maintain the integrity and stability of the organism due to its complex structure. The skin is composed of several layers of cells, including the stratum corneum (SC), which forms the main protective barrier. Ceramides (CER) are one of the main types of barrier lipids found in the SC. These lipid molecules, along with other lipids, create a hydrophobic matrix that protects the skin from dehydration and other external influences. The lack of CER in the skin barrier leads to the disruption of its function and the worsening of the skin condition. This is associated with many diseases, such as dermatitis, psoriasis, and others. The study of CER in the SC is important to understand the mechanisms of skin protection and to develop new therapeutic approaches for the treatment of skin diseases. Topical administration of barrier lipids, especially CER, is one possible treatment route for skin diseases. Therefore, the aim of this work was to prepare...
Mycobacterium tuberculosis - structure and functions of the cell wall
Kukrálová, Simona ; Janďourek, Ondřej (advisor) ; Jílek, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Study program: Bioanalytical laboratory diagnostics in healthcare Candidate: Bc. Simona Kukrálová Supervisor: PharmDr. Ondřej Janďourek, Ph.D. Title of diploma thesis: Mycobacterium tuberculosis - structure and functions of the cell wall Mycobacterium tuberculosis is an intracellular pathogen that causes a disease called tuberculosis, which, along with other selected diseases, is still one of the leading causes of mortality in the world. It is estimated that more than a million people succumb to the disease each year. The remarkable structure of the cell wall of mycobacteria has a great influence on the treatment of tuberculosis itself, together with the ever-increasing incidence of multidrug- resistant and extensively resistant strains, especially in Mycobacterium tuberculosis. The research of mycobacteria is given great attention. Efforts to find new substances with antimycobacterial effect acting on individual components of the cell wall, preferably on the cell wall as a complex, are actual and are part of national as well as international programs. Theoretical part of this diploma thesis deals with current knowledge about mycobacteria with emphasis on cell wall, epidemiology of tuberculosis...
Polymeric nanoparticles for poorly water soluble drugs delivery
Nekolová, Martina ; Holas, Ondřej (advisor) ; Smékalová, Monika (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Mentor: PharmDr. Ondřej Holas, Ph.D. Student: Martina Nekolová Title of thesis: Polymeric nanoparticles for poorly water-soluble drugs delivery Polymeric nanoparticles represent a modern drug form. One of the main advantages is influencing the pharmacokinetic properties of the administered substance - e.g. increasing solubility in water. They enable the targeted delivery of the drug to the affected tissue and this way minimize adverse effects. This could be of great benefit to the therapy of cancer or inflammatory diseases. Both the target tissue and the nanoparticles must have some specific properties. For particles, it is, for example, size and surface charge. The aim of this work was to prepare nanoparticles with a substance poorly soluble in water, represented by curcumin. The particles were prepared by the nanoprecipitation method with different types of poly(lactic-co-glycolic acid) (PLGA) copolymer. A 50:50 linear PLGA polymer and a branched PLGA A2 polymer were used. The prepared nanoparticles were compared on several parameters - particle size and polydispersity, encapsulation efficiency (EE), drug-loading capacity (DLC) and dissolution profile. PLGA 50:50 was found to provide...
Functional Ultrastructure of Hymenopteran Stingers: Devastating Spear or Delicate Syringe
ČERNÝ, Jan
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.
Financial law aspects of collective real estate investments in the Czech Republic
Samek, Michal ; Boháč, Radim (advisor) ; Večeř, Miroslava (referee)
v anglickém jazyce Financial law aspects of collective real estate investments in the Czech Republic The primary objective of the thesis is to analyse how the financial law regulating collective investments and their taxation is applied to collective real estate investments in the Czech Republic. In the introduction, the thesis positions the relevant legal regulation within the framework of the theoretical classification of the financial law system and demonstrates the importance of collective real estate investments by pointing out the number of entities operating on the market and the volume of assets managed within this investment activity. The thesis discusses the main sources of law, both formal and material, relevant to the field of collective investment and its taxation. With regard to key legislation, the thesis emphasises in particular Act No. 240/2013 Coll., on Investment Companies and Investment Funds, as amended, and the subordinate legislation implementing this regulation. The thesis describes the basic institutional structure of the collective investment market and the regulation of the entities operating on it, in particular in the form of investment companies and investment funds and investors in collective investment securities. The thesis also highlights the importance and scope...
Role of transcription factors MEIS in the origin and development of the neural crest
Fábik, Jaroslav
Unique to the vertebrate embryo, neural crest cells represent a multipotent cell population that migrates throughout the body and gives rise to a multitude of different types of cells and tissues. Cranial neural crest cells populate the developing pharyngeal arches and establish skeletogenic condensations that generate the future bones and cartilages of the face and neck. Moreover, these cells send out and receive signals from adjacent tissues of non-neural crest origin, such as the mandibular epithelium and muscle precursor cells. Such reciprocal interactions give rise to organs and structures, for instance, to the tongue. The aim of this work was to elucidate the roles of homeodomain-containing MEIS transcription factors in neural crest cells and in craniofacial development, by using a mouse model with conditional inactivation of Meis2 gene in neural crest cells. We show that transcription factor MEIS2 is expressed in the medial region of the developing mandible and in the developing tongue. Conditional Meis2 inactivation using the Wnt1-Cre2 mouse strain caused mandible and tongue hypoplasia, and ectopic bone formation at the expense of tongue development. These mandibular arch anomalies were accompanied by the loss of Hedgehog signaling in the mandibular epithelium, expanded RUNX2 expression in...
Complex morphological, immunohistochemical, molecular genetic and clinical pathological analysis of rare types of ovarian cancers
Galko, Kamila ; Nachtigal, Petr (advisor) ; Němečková, Ivana (referee)
Ovarian carcinomas are heterogenous group of diseases comprising various histotypes. Ovarian carcinomas as a whole are associated with the highest lethality among the female genital tumors. Currently, 5 main types of carcinomas are recognized: high grade serous carcinoma, low grade serous carcinoma, endometroid carcinoma, clear cell carcinoma and mucinous carcinoma. Other types, e.g. Brenner tumors, are very rare. Ovarian carcinomas are very diverse group with various precursors, morphology, genetic aberrations, epidemiologic and clinical, features, therapy and prognosis. The most studied and understood is high grade serous carcinoma with high incidence (up to 70 % of ovarian carcinomas). The number of studies dedicated to this tumor is still increasing. Other types of carcinomas are much less frequent, therefore related studies are rarer. Due to the rapid development of targeted therapy, it is necessary to evaluate the tumors not only morphologically but also on immunohistochemical and genetic level. Detection of neoantigens may indicate the mutation load of a tumor, it is also possible to evaluate status of mismatch repair (MMR) proteins and other features leading to chromosomal aberrations. In contrast to the high grade serous carcinoma, as for other types of carcinomas, knowledge about their...
Between hope and frustration. Reconstructions and new realisations in historical parts of Prague at the turn of the 19th and 20th century in the context of contemporary considerations on monument conservation
Uhlík, Jan
Thedissertationdealswiththeissueofreconstructionsandnewrealizationsinhistoricalparts of Prague (Old and New Towns of Prague, Lesser Town, Hradčany, Josefov and Vyšehrad) at the end of the 19th and the beginning of the 20th century against the background of period discussions about the content and new direction of monument care, as reflected in selected projects (whether implemented or unrealized) representing the construction activities of the time in the metropolis. The work not only raises questions about the immediate conceptual and stylisticsolutionsused byindividualarchitects, butalsoconsidersthemore generalissues of the development of monument care in the Czech lands in the period under review. Its focus is on the analysis of the influence of current ideas and opinions in the field of theory of monument care on construction practice represented by individual cases and the identification of the retroactive impact of practical experience on the form of field theory. Individual case studies (discussed projects) are selected to cover both major Prague urban projects at the turn of the 19th and 20th centuries, as well as (un) implemented transformations of selected buildings and architectural ensembles in this period. The work is primarily focused on the period between 1890 and 1918, i.e....

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