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Influence of extracellular matrix environment on gene expression in liver myofibriloblasts
Jiroutová, Alena ; Kanta, Jiří (advisor) ; Ehrmann, Jiří (referee) ; Sedláček, Radislav (referee)
Influence of extracellular matrix environment on gene expression in liver myofibroblast (summary) Hepatic stellate cells (HSC) and liver myofibroblasts (MF) are two cell populations most likely responsible for the synthesis of majority of connective tissue components in fibrotic liver. They differ in their origin and location in the liver, and in the spectrum of genes they express. HSC are located in Disse spaces of normal rat liver around the sinusoids, in fibrotic liver they become activated, proliferate and they undergo transdifferentiation into myofibroblast-like cells. Myofibroblasts are heterogenous cell population that consists at least of portal pMF, septal sMF and interface iMF. pMF, which are adjacent to bile duct epithelia, may be a mediator of billiary type fibrosis. sMF are located within and along the collagenous septum in cirrhotic liver. Little is known about the expression of genes involved in connective tissue metabolism in MF cultured in fibrin or collagen gels that more closely resemble natural cell environment. Fibrin is deposited in liver at sites of injury and collagen type I forms a substantial part of fibrotic septa. In our study oligo cDNA array analysis was used to determine gene expression in quiescent HSC, activated HSC and MF isolated from both normal and CCl4-cirrhotic liver....

Genetic factors in aetiology and phatogenesisof low gamma-glutamyltransferase cholestasis and hereditary jaundice
Cebecauerová, Dita ; Jirsa, Milan (advisor) ; Brdička, Radim (referee) ; Macek, Milan (referee)
(English) Recent progress in understanding the molecular mechanism of hepatobiliary disorders enabled the improvement of diagnostic accuracy and promoted the study of the regulation of gene expression and its potential modifying factors. Current achievement in the field of genetically determined cholestatic disorders is well illustrated in this thesis, focused on low gamma-glutamyltransferase (γGT) cholestasis and hereditary jaundice. The study describes several distinct defects of hepatocyte transport system, characterises underlying mutations and their phenotypic consequences and, finally, extends these studies for detailed characterisation of ATP8B1 gene regulatory regions. Chapters related to low γGT cholestasis - characterise rare type of mutation associated with benign course of PFIC type I (formerly BRIC1) and explain the putative mechanisms of mutation origin. - provide extensive study of severe forms of ABCB11 deficiency (PFIC2) including genotype-phenotype correlations in 109 affected families, evaluation of the specific ABCB11 genotypes' impact on BSEP immunostaining and risk of hepatobiliary malignancy. - identify and characterise yet unknown regulatory regions of ATP8B1, a gene mutated in Progressive Familial Intrahepatic Cholestasis type I. The studies demonstrate the complex structure...

Laboratory diagnostics of micrometastases in breast cancer patients
Mikulová, Veronika ; Zima, Tomáš (advisor) ; Svoboda, Marek (referee) ; Průša, Richard (referee)
Introduction: The presence of circulating tumor cells (CTC) in the peripheral blood has been associated with worse prognosis and early relapse in breast cancer patients. CTC determination in the peripheral blood has been considered as a liquid biopsy. The aim of this project was to analyze the presence of CTC followed by their molecular characterization with the potential use not only as a new biomarker for real-time monitoring of therapy efficacy but also as a suitable tool for patient's stratification and individualization of treatment for breast cancer. Methods: A total of 54 patients with diagnosed early breast cancer were enrolled into a prospective study. Ten millilitres of peripheral blood were sequentially collected to test for the presence and characterization of CTC during the follow-up of patients. CTC isolation and detection was performed by AdnaTest BreastCancer™ (AdnaGen AG, Germany), which is based on the detection of EpCAM, HER2 and MUC1 specific transcripts in enriched CTC- lysates. cDNA from isolated CTC has been further used for newly optimized qPCR assays for breast tumor and therapy resistance associated genes: TOP1, TOP2A, CSTD, ST6GAL, KRT19 and reference gene actin. qPCR results have been analyzed by Genex software (MultiD Analysis). Results: 195 blood samples have been...

Laboratory diagnosis of Clostridium difficile
JANDOVÁ, Romana
Clostridium difficile toxin with production is the most common cause of nosocomial enteric infections. It causes inflammatory bowel disease called Clostridium difficile infection (CDI) of varying severity - from trivial diarrhea to life-threatening conditions such as paralytic ileus and toxic megacolon. C.difficile still escapes the attention of the general public and is in the background of other bacteria, such as MRSA. Clostridium difficile is a strictly anaerobic bacterium. It is a gram-positive rod forming an oval subterminal spores. C. difficile can produce two types of toxins - and toxin A (enterotoxin) and toxin B (a cytotoxin). Due to the toxin causes damage of the intestinal epithelium and deeper layers of the bowel wall. Into inflammatory ulceration that cover of the pseudomembrane. Some strains produce more binary toxin, whose exact function is not underwood yet. It is assumed that potentiates the effect of toxins A and B to increase their concentration. To demonstrate the CDI must remove the stool sample into a sterile tube. In the bacteriology workplace in Czech Budweis Hospital is being made direct conclusiveness of antigen and toxin by immuncgromatography method. It is a membrane-enzyme immunoanalysis for the detection of antigen - glutamate dehydrogenase (GDH) and toxin A / B. Negative result excludes GDH with high reliability clostridial infection. For confirmed CDI is considered proof toxigenic strain of C. difficile. This is evident from the result of either immunochromatography which is demonstrated both the antigen and the toxin, or identity of the gene for toxin B by PCR. If you find out in direct detection only positive antigen, the sample is sent for PCR testing to the Laboratory of Molecular Biology and Genetics. Regardless of the outcome of the immunochromatography, the microscopic specimen stained by Gram are being produce from reces. In the case of proven C. difficile toxin is carried anaerobic culture test that takes two days. For identification of accrued bacteria is used latex agglutination. This is a method in which IgG antibodies bound to latex particles specifically bind to the antigens of the cell wall. To identify the bacteria can be also used the VITEK - MS machine that uses a laser ionization method in the presence of the matrix, followed by mass spectrometry. In case of a positive culture findings Clostridium difficile is being from grown culture set sensitivity to antibiotics by E-test and disk diffusion methods For the year 2011 the Department of Bacteriology examined 291 samples of feces. 13,4 % of these samples had positive antigen and toxin in an imunochromatographyc examination; 15,1 % had a positive antigen and negative toxin and 71,5 % were negative. 74 samples was positive in C. difficile toxin. These samples were subsequently conducted to culture examination - 62,2 % were positive. Most positive samples were sent from the infectious department. It has been examined 53,6 % of women and 46.4 % of mens. Percentage of toxigenic strains of both sexes were virtually identical - 25 %. All strains were susceptible to vancomycin and only one strain was resistant to metronidazole.

Study of molecular markers correlating with prognosis and result of therapy colorectal carcinoma.
Protivová, Martina ; Souček, Pavel (advisor) ; Hromadníková, Ilona (referee)
Colorectal cancer is one of the most common cancer in this country and abroad. A major problem in the treatment of this disease is interindividual variability in response to treatment, since a large proportion of patients show resistance or adverse toxicity to the drug. The cause of this variability can be an individual's genetic makeup. From this perspective a need to find molecular markers for prognosis of the disease and markers through which we can predict response to therapy is growing. The main aim of this study was to find differences in gene expression between healthy and tumor tissue from patients well and poorly responding to treatment based on 5-fluorouracil and compare the results to clinical data. This study aimed to evaluate gene expression of 14 potential molecular markers involved in 5-FU pathways involving metabolism, transport, and objectives of the drug. Patients selection for the study was based on 5-FU regimens treatement. Expression was evaluated in two independent sets consisting of patients with indicated palliative or adjuvant chemotherapy. For each patient malignant and paired nonmalignant tumor tissue was available. Gene expression in these samples was measured using real-time RT-PCR with relative quantification using the preamplified cDNA. In the first phase the gene...

není uveden
Soukup, Viktor ; Babjuk, Marek (advisor) ; Mareš, Jaroslav (referee) ; Novák, Jaroslav (referee)
Immunohistochemical examination of microvascular density can be an additional prognostic factor in patients with superficial urinary bladder carcinoma, nevertheless, more extensive studies need to be carried out. Maximal microvascular density correlated with a recurrence free interval and in a case of bigger group of patients could be statistically significant. The statistical correlation between MVD and a nuclear p53 accumulation is that significant that we assume the p53 importance in the angiogenesis regulation of superficial urinary bladder carcinoma. The p53 positivity in non-tumor mucosa of urinary bladder in patients with superficial bladder cancer correlates with higher risk of tumor recurrence. According to our results the reason of urinary bladder carcinoma multifocality is genetic instability present in the whole urothelium at the time of tumor diagnosis. The PAX5 gene expression is a frequent finding in superficial transitional cell carcinoma of the bladder. From the prognostic point of view, high levels of PAX5 expression seem to be connected with higher recurrence and progression rates. The extent of lamina propria invasion seems to be a clinically relevant prognostic factor for progression of T1 bladder transitional cell carcinoma. Finding T1b tumor is connected with the risk of understaging....

Impact of NKR-P1 polymorphism on Ly49 receptors expression in hybrid mouse strains (C57BL/6 x Balb/c, F10-12)
Holubová, Martina ; Fišerová, Anna (advisor) ; Vomastek, Tomáš (referee)
Impact of NKR-P1 polymorphism on Ly49 receptors expression in hybrid mouse strains (C57BL/6 x Balb/c, F10-12) Abstract Natural killer (NK) cells constitute the subpopulation of large granular lymphocytes which mediate spontaneous immune response against infected, transformed or allogeneic cells and thus represent an important component of the innate immunity. NK cells express a wide repertoir of surface receptors which can be either activating or inhibitory and which mediate NK cell recognition and regulation of cytolytic activity. NKR-P1 and Ly49 receptor families belong to the most important murine NK receptors. Both NKR-P1 and Ly49 families are members of C-type lectin-like superfamily of receptors encoded by natural killer gene complex (NKC) on chromosome 6 and include both activating and inhibitory members. The aim of this diploma thesis was to elucidate the impact of Nkr-p1c gene divergence on Ly49 receptors expression and to find out whether the Ly49 and Nkr-p1 gene clusters (which are localized on opposite ends of NKC) are inherited independently or whether the NKC domain is inherited as a complex. The second research interest was to illustrate the influence of the above mentioned divergence on cytotoxic activity of NK cells and tumor growth. In this study, inbred mouse strains C57BL/6 and Balb/c...

Comparison of sequence variations in genes of biotransfromation enzymes in some carcinoma
Turková, Lucie ; Tavandzis, Spiros (referee) ; Bóday, Arpád (advisor)
Xenobiotic biotransformation process and its capacity is crucial for xenobiotic chemicals elimination that may cause damage toward cell structures. The effectiveness of the enzymes included in this process depends on the gene variants that encodes them. The aim of this work was to compare certain polymorphisms of selected genes between cases and control groups. Studied polymorphisms were null genotypes of the glutathione S-transferase gene M1 and T1 and the insertion of TA dinucleotide in the promotor region of UDP-glucuronosyl transferase 1A1. The number of cases group was six included patients with colorectal, lung, prostate, breast, pancreatic and head and neck cancer. Total number of analysed individuals was 1 118 for cancer cases and 470 for healthy controls. The control group was divided into two groups, the first one was called general and the second one was called special included healthy individuals with no cancer history in their closest family members. Gilbert syndrome (GS) is caused by homozygous insertion of the TA dinucleotide in the TATA box of the gene UGT1A1 and it causes elevated bilirubin levels. Bilirubin is a potent antioxidant in human body, so the aim was to attest its protective effect toward cancer. We expected lower frequency of GS as a protective factor in the cases groups compared with controls. This hypothesis was confirmed in the breast cancer group (GS frequency 10,0 %) and pancreatic cancer group (GS frequency 11,1 %). In the general and special control groups the frequency of GS was 16,0 % and 15,4 % respectively. Although the other case groups show lower frequency of GS, the results weren´t statistically significant. Null GSTM1 genotype was observed with 50,4 % frequency in the general control groups and with 55,3 % frequency in the special control group. Neither the one of the cases groups hasn´t showed significantly lower percentage of null genotype. Despite expectation we observed statistically significant lower frequency of null genotype in the group of lung and pancreatic cancer group (37,4 % and 39,3 % respectively). According to this study, we can say that the lack of glutathione S-transferase M1 activity is not a risk factor for cancer development. Null genotype of GSTT1 wasn´t identified in both control groups at all. In case groups of breast and prostate cancer, there was only one individual carrying the null GSTT1 genotype. Statistically significant higher frequency of this polymorphism was observed in patients with colorectal cancer (9,7 %), lung cancer (17,2 %), pancreatic cancer (3,0 %) and head and neck cancer (15,9 %). In these groups the lack of glutathion S-transferase T1 activity might be considered as risk factor for cancer development. Nevertheless, for further verification it needs to take more investigation in this field, especially enlarge the number of patient in the case groups of head and neck, lung and pancreatic cancer.

Immuno-biological Aspects of Head and Neck Squamous Cell Carcinoma
Bouček, Jan ; Říhová, Blanka (advisor) ; Fučíková, Terezie (referee) ; Šlapák, Ivo (referee)
The process of tumorigenesis is conditioned by change or the series of changes at a gene level. The development of cancer is largely pre-ordained by this change, but very important role is played by other factors. In case of solid tumors it is mainly a tumor microenvironment, where the tumor cells are in contact with stromal cells, especially fibroblasts, and immune cells. Tumor microenvironment can also critically modify the nature and intensity of anti- tumor immune response. Squamous cell carcinomas of the head and neck are the sixth most common cancer, which affect each year more than half a million patients worldwide. Despite advances and improvements in all treatment modalities, achieved therapeutic results even in Western countries are not satisfactory and remain at approximately the same values for several decades. At prezent, the 5 years survival rate, regardless of the location and stage of disease, is approximately only 40%. In the prezented work the immunological and biological aspects of squamous cell carcinoma of the head and neck are discussed. It summarizes the recent findings on the molecular basis of the behavior of tumor cells and the influence and significance of regulation of the immune system for the clinical course of disease and the modern therapeutic approaches.

HIV - 1 Protease: Insights into Drug Resistance Development
Grantz Šašková, Klára ; Konvalinka, Jan (advisor) ; Forstová, Jitka (referee) ; Dohnálek, Jan (referee) ; Schiffer, Celia (referee)
Amino acid changes within HIV protease or its substrate that decrease the susceptibility to protease inhibitors represent a highly complex issue still not yet fully understood. Various mechanisms by which this often complicated pattern of mutations influence drug binding needs to be analyzed on a molecular level by a series of methods including experiments with recombinant viruses, biochemical enzyme analysis, structural and thermodynamical studies or molecular dynamics. Each result may help to complete the overall picture of protease inhibitor resistance evolution and therefore contribute to the design of more powerful 3rd generation HIV/AIDS drugs. This thesis presents several analyses of HIV resistance development on molecular level. We have focused on the nelfinavir resistance pathway, lopinavir mutation score, emergence of amino acid insertions in HIV protease gene and their contribution to protease inhibitor resistance and finally we analyzed a highly mutated protease species isolated from patients failing darunavir therapy. Since we are able to accomplish a wide combination of techniques, we could explain and put together some pieces of viral evolution considering the final steps of HIV life cycle and also provide knowledge necessary for novel inhibitor design. Aims of the Project There were...