National Repository of Grey Literature 37 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
The study of model lipid membranes containing omega-hydroxylated ceramides
Svatošová, Linda ; Opálka, Lukáš (advisor) ; Pullmannová, Petra (referee)
Charles University, Faculty of pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Candidate: Linda Svatošová Supervisor: PharmDr. Lukáš Opálka, Ph.D. Title of diploma thesis: The study of model lipid membranes containing omega- hydroxylated ceramides Acylceramides (EO-Cer) belong to a class of ceramides (Cer) with an ultralong acyl chain whose ω-hydroxyl group is esterified with linoleic acid. The importance of EO-Cer lies in the formation of the long periodicity phase (LPP) and the corneocyte lipid envelope (CLE), which are indispensable components for the skin functioning as a barrier. Disorders in EO-Cer biosynthesis are associated with insufficient production of CLE and LPP leading to many skin diseases, including some types of ichthyosis. One of the enzymes that is deficient in such ichthyoses is PNPLA1. Insufficient function of this enzyme disables ω-esterification with linoleic acid, and thus the formation of EO-Cer. On the contrary, their precursors, i.e. ω-hydroxylated ceramides (O-Cer), are cumulated. The aim of this thesis was to prepare model membranes containing O-Cer and to study the effects of O-Cer on the lipid organization and barrier properties of model membranes. Within this thesis, two types of membranes were prepared - the first type were membranes...
The development of reliable method for glucosylation and lactosylation of sphingolipids
Hošek, Adam ; Opálka, Lukáš (advisor) ; Karabanovich, Galina (referee)
Title of the master thesis: The development of reliable method for glucosylation and lactosylation of sphingolipids Candidate: Adam Hošek Supervisor: PharmDr. Lukáš Opálka, Ph.D. Consultant: Dr. Georgios Paraskevopoulos, Ph.D. Charles University, Faculty of Pharmacy in Hradec Králové Skin Barrier Research Group, Department of Organic and Bioorganic Chemistry Ceramides are hydrophobic sphingolipids consisting of a sphingoid base and an acyl chain. They are found in the stratum corneum, the uppermost layer of the epidermis, where they are important part of the skin barrier, but they can also be found in brain tissue and inside human cells. Glucosylceramides are the simplest glycosphingolipids, and they contain a single glucose molecule in their structure. They are found in all types of human cells, where they not only serve as precursors for the biosynthesis of other, more complex glycosphingolipids, but also have their own physiological functions. The most significant is their influence on cell growth, development, differentiation and apoptosis. Disruptions in their synthesis or degradation can lead to serious health problems and are also a risk factor for the future development of a wide range of diseases. Their total absence in the body is incompatible with life. A more thorough study of their...
Synthesis and Reactivity of Enynes with Terminal Double Bond
Grobař, Bartoloměj ; Matouš, Petr (advisor) ; Opálka, Lukáš (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of organic and bioorganic chemistry Candidate: Bartoloměj Grobař Supervisor: PharmDr. Petr Matouš, Ph.D. Title of thesis: Synthesis and reactivity of enyns with terminal double bond This work focuses on synthesis of structures containing terminal vinyl moiety and their subsequent reactivity. We tested various approaches that lead to formation of enynes, which are then cyclized using gold complex catalyst into tetrahydropyridines. Both utilize the addition of propargylamine protected by 4-methoxybenzenesulfonyl group to substituted butynone and methoxyphenyl propiolates. Tetrahydropyridine molecules that are successfully created, are further derivatized forming polycyclic structures.
Synthesis and study of hyaluronic acid derivatives modified on carboxyl
Volfová, Gabriela ; Roh, Jaroslav (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Author: Gabriela Volfová Supervisors: Mgr. Radovan Bu a, Ph.D. doc. PharmDr. Jaroslav Roh, Ph.D. Title: Synthesis and study of hyaluronic acid derivatives modified on carboxyl Abstract: Hyaluronic acid (HA) is a naturally occurring linear polysaccharide. Due to its biocompatibility and non-immunogenicity, HA and its derivatives are widely used in various biological and medical applications. The e cacy of each formulation is strongly related to the molecular weight (MW) of the HA used. Unfortunately, various factors can a ect the MW during the manufacturing process. Elevated tem- perature required during the sterilization process is one significant example, which can lead to a reduction in molecular weight and result in a loss of some desired properties of the final product. This work focuses on the synthesis of HA amides formed on its free carboxyl group and subsequently studying the e ect of this modifi- cation on the degradation rate at elevated temperature. Three final compounds were prepared by reacting HA with various amines using 4-(4,6-dimethoxy-1,3,5-triazin-2- yl)-4-methylmorpholinium chloride (DMTMM), all of which underwent degradation noticeably faster than native HA.
Synthesis of aza-analogs of compounds with high antimycobacterial activity
Khajl, Tomáš ; Karabanovich, Galina (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Author: Tomáš Khajl Supervisor: Ing. Galina Karabanovich, Ph.D. Title of Diploma Thesis: Synthesis of aza-analogs of compounds with high antimycobacterial activity Tuberculosis (TB) is widespread disease, caused by bacteria M. tuberculosis. TB is the 13th leading cause of death and was the 2nd leading cause of death from infectious diseases in 2020. TB is also the most common cause of death in HIV-positive people. Due to increasing resistance to 1st line and 2nd line drugs, research into new anti-TB drugs is needed. This diploma thesis is based on previous results obtained at KOBCH FaF UK, where 5-alkyl/aryl-2-((3,5-dinitrobenzyl)sulfanyl)-1,3,4-oxadiazoles were invented. These 1,3,4- oxadiazoles showed excellent antimycobacterial activity with minimal inhibitory concentration (MIC) values of 0.03 μM. This activity is much higher than that of isoniazid, first-line antituberculotic drug, which has MIC values of 0.5 μM. In previous work, it has been shown that the 3,5-dinitrophenyl fragment is crucial to the high antimycobacterial activity and that derivatives with a 1,3,4-oxadiazole cycle show the highest potency compared to 1H/2H-tetrazole and 1,2,4-triazole derivatives. However, the question of...
Synthesis of ceramides derived from 6-hydroxysphingosine
Kavuljak, Juraj ; Opálka, Lukáš (advisor) ; Matouš, Petr (referee)
Title of the Master thesis: Synthesis of ceramides derived from 6-hydroxysphingosine Candidate: Juraj Kavuljak Supervisor: PharmDr. Lukáš Opálka, Ph.D. Consultant: Mgr. Veronika Ondrejčeková Charles University, Faculty of Pharmacy in Hradec Králové Skin Barrier Research Group, Department of Organic and Bioorganic Chemistry Ceramides (Cer), belong to the group of sphingolipids naturally found in each cell. One of their principal functions is cell signaling. We can find Cer in the uppermost layer of epidermis (stratum corneum), where the concentrations of these lipids are highest in the whole human body. Cer form an intercellular multi-lamellar lipid matrix. This lipid mass is composed of cholesterol and free fatty acids as well. The major function of stratum corneum is to protect the body from the excesive transepidermal water loss, provide internal homeostasis and create a protective barrier against harmful substances from external environment. Cer are amides of long aminoalcohols with a fatty acid attached to their primary amino group. 6-hydroxysphingosine (H) is specific for human epidermis, but its function and biosynthesis in skin is still not completly understood. Some studies showed lower concentrations of 6-hydroxysphingosine-based Cer in skin of patients suffering from atopic dermatitis....
Synthesis of fluorinated serine derivatives and study of their effect on skin barrier function
Župina, Richard ; Vávrová, Kateřina (advisor) ; Opálka, Lukáš (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Supervisor: Prof. PharmDr. Kateřina Vávrová, Ph.D. Consultant: Dr. Georgios Paraskevopoulos, Ph.D. Author: Richard Župina Title of the thesis: Synthesis of fluorinated serine derivatives and study of their effect on skin barrier function The human skin serves as a barrier against physical, chemical and microbial injury. When the skin barrier is perturbed, there is a possibility of microbial infiltration and biochemical damage. Ceramides, as essential components of the skin lipid layer, help to maintain the barrier integrity. Decreased content of skin ceramides in epidermis is connected with skin diseases such as atopic dermatitis and psoriasis. Previous findings of our research group proved that a ceramide analogue with similar steric and hydrophobic parameters to skin ceramides could selectively supplement the recovery of perturbed human skin barrier. The goal of this study was to design a convenient synthesis of ceramide analogues derived from L-serine with two long aliphatic chains. The first chain is amidically bound lignoceric acid and the second chain is either a 10 or a 14 carbon polyfluorinated chain conjugated with the rest of the molecule by an ester bond. Furthermore, the aim of this...
Preparation of the human skin barrier model using thin lipid film deposition
Suciu-Šubert, Karina ; Pullmannová, Petra (advisor) ; Opálka, Lukáš (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Student: Karina Suciu-Šubert Supervisor: Mgr. Petra Pullmannová, Ph.D. Title of diploma thesis: Preparation of the human skin barrier model by using thin lipid film deposition The uppermost part of the human skin - the stratum corneum, which protects the body from the external environment, is made up of cornified cells - corneocytes, which are surrounded by the extracellular matrix of highly ordered lipids: ceramides (Cer), fatty acids and cholesterol. The protective barrier is constantly renewed with so-called keratinocytes, which differentiate to corneocytes and finally desquamate from skin to surface. The corneocyte envelope replaces plasma membrane of corneocytes. It consists of proteins (eg. involucrin) and a lipid monolayer consisting mainly of ω-hydroxyceramides which are attached to the protein segments by covalent bonds. The task of this diploma thesis was the preparation of the human skin barrier model by using thin lipid film deposition. Two different lipid mixtures were based on Cer NS or Cer EOS and NS. The mixtures were applied on the hydrophilic or hydrophobic substrate by spraying with Linomat V. The amount of lipids and consequently the number of theoretical lipid layers on the...
Quantification of skin ceramides in patients after oncological treatment
Voláková, Eliška ; Opálka, Lukáš (advisor) ; Roh, Jaroslav (referee)
Charles University, Faculty of pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Candidate: Eliška Voláková Supervisor: PharmDr. Lukáš Opálka, Ph.D. Title of diploma thesis: Quantification of skin ceramides in patients after oncological treatment Ceramides are one of the three basic lipid components present in the stratum corneum of human skin. Alterations in the ratio of individual ceramides are associated with disruption of skin barrier function. Such changes have been observed not only in skin diseases of the non-cancerous type, but also as a consequence of cancer. The main aim of the present study was to investigate the difference in the representation of skin ceramides in the stratum corneum of healthy patients and patients after cancer. Samples were collected from five groups of patients, four of which represented cancer patients with different types of treatment: tumor resection, chemotherapy, radiation or a combination of chemotherapy and radiation. The remaining fifth group consisted of control samples from volunteers without a diagnosis of cancer. Samples were obtained by tape-stripping from an identical site on patient forearm, followed by protein determination. Cancer patient samples were compared with control samples in terms of different water loss through the...
Synthesis and study of hyaluronic acid derivatives modified on carboxyl
Volfová, Gabriela ; Roh, Jaroslav (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Author: Gabriela Volfová Supervisors: Mgr. Radovan Bu a, Ph.D. doc. PharmDr. Jaroslav Roh, Ph.D. Title: Synthesis and study of hyaluronic acid derivatives modified on carboxyl Abstract: Hyaluronic acid (HA) is a naturally occurring linear polysaccharide. Due to its biocompatibility and non-immunogenicity, HA and its derivatives are widely used in various biological and medical applications. The e cacy of each formulation is strongly related to the molecular weight (MW) of the HA used. Unfortunately, various factors can a ect the MW during the manufacturing process. Elevated tem- perature required during the sterilization process is one significant example, which can lead to a reduction in molecular weight and result in a loss of some desired properties of the final product. This work focuses on the synthesis of HA amides formed on its free carboxyl group and subsequently studying the e ect of this modifi- cation on the degradation rate at elevated temperature. Three final compounds were prepared by reacting HA with various amines using 4-(4,6-dimethoxy-1,3,5-triazin-2- yl)-4-methylmorpholinium chloride (DMTMM), all of which underwent degradation noticeably faster than native HA.

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