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In vitro screening of novel potentially active antibacterial compounds II
Zbořilová, Eliška ; Janďourek, Ondřej (advisor) ; Vejsová, Marcela (referee)
Charles University Faculty of Pharmacy in Hradec Kralove Department of Biological and Medical Sciences Study program: Specialist on Laboratory Methods Author: Bc. Eliška Zbořilová Supervisor: PharmDr. Ondřej Janďourek, Ph.D. Title of diploma thesis: In vitro screening of novel potentially active antibacterial compounds II Key words: antibiotics, bacteria, resistance, minimal inhibitory concentration, bacterial susceptibility to antibiotics This diploma thesis deals with testing of the efficacy of new antimicrobial agents on selected representative bacteria. The work consists of a theoretical part and a practical part. The theoretical part includes the history and the present of antibiotics describing current issues and the layout of the antibiotic policy in the Czech Republic and in the world. It deals with the characteristics of drugs, below which are described their importance, division, effects, resistance. Furthermore, this part of work describes detailed mechanism of action for two selected groups of compounds. Last but not least, this work portrays the methods that are used to determine the sensitivity of bacteria to antibiotics. The practical part deals with the description of the whole work process, including the characteristics of used bacterial strains and the list of tested substances....
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An examination (analysis) of susceptibilities to antibiotics of the strain Staphylococcus aureus performed by phenotypic methods in conventional microbiological laboratory and interpretation of its results.
MARIŇÁKOVÁ, Barbora
The aim of bachelor´s thesis is the understanding and the correct interpretation of results of susceptibility to antibiotics of the strain Staphylococcus aureus from serious clinical materials as a hemoculture, a peritoneal fluid from joints and abscesses, a smear from wounds, tissues during infectious total artificial joints, samples of an urine, materials from the lower respiratory tract and another clinical samples. According to data which have been used, my aim also have been to prove or eventually disprove the first hypothesis, that makes sense to collect also hemocultures from patient whose result in the serious clinical material contained the strain of Staphylococcus aureus. Prove or disprove the second hypothesis that with the number of positive results of the strain of Staphylococcus aureus in samples of urine will be in the same time the most positive hemocultures in percentage in comparison with results of the strains of Staphylococcus aureus in other clinical materials. Defined targets were reached by regular practical education in the Department of Clinical Microbiology. I had adopted a methodology of examination of susceptibility in the department and then have practiced under the professional supervision. Before the practical part of my thesis, I have had to elaborate and learn theoretical part of it. In that part is deeply described the kind Staphylococcus aureus, antibiotical treatment of this strain and the list of mostly tested antibiotics in the routine microbiological laboratory. In the practical part of the thesis I am focusing on the determination of sensitivity to antibiotics by the disk diffusion method and a defining minimal inhibition concentration. I have interpreted results and for example, I have depicted mostly occurred antibiograms and equally less occurred or rare ones. Then I have processed results of sensitivity of Staphylococcus aureus. The examined set has been containing 588 samples of positive Staphylococcus aureus. 72 samples from the set have been MRSA positive. A representation of positive hemocultures has been examined too in currently or earlier found positive materials. Positive hemocultures in positive materials have been found in ca 5,2 % of all positive clinical materials. The most positive hemocultures were found in previous positive samples of urine ca 17 %. The second highest positivity of hemocultures was in samples from bones and joints ca 14 %. Then artificial materials ca 13 %, venous catheters ca 10 %, abscess ca 6 %, materials from respiratory tract ca 4 %, soft tissues ca 3 % and wounds ca 2 %. The significant gained finding and conclusion of the thesis is the fact that during serious staphylococcus infections the sampling of hemocultures is indicating as a necessity and as an obligation of the sampling of hemocultures of a patient is finding of the strain of Staphylococcus aureus in the sample of urine.
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Advanced methods of antimicrobial activity screening
Dolinská, Dagmar ; Janďourek, Ondřej (advisor) ; Konečná, Klára (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Dagmar Dolinská Supervisor: PharmDr. Ondřej Janďourek, Ph.D. Work title: Advanced methods for testing antimicrobial activity Goal: The aim of the work in the theoretical part was to summarize methods of antimicrobial screening focusing on antimycotics and in the practical part to evaluate the antifungal activity of 47 tested substances using the microdilution broth method. Methods: The substances were tested using quantitative microdilution broth method on eight strains of yeast and fibrous fungi. These were Candida albicans, Candida krusei, Candida parapsilosis, Candida tropicalis, Aspergillus fumigatus, Aspergillus flavus, Absidia corymbifera and Trichophyton interdigitale. Results: The highest antimycotic activity was demonstrated by compound Ac-0a, where we recorded after 24 hours of incubation activity against all eight strains. However, it was not able to stop the growth of three strains after 48 hours of incubation, the strains concerned were Candida parapsilosis, Aspergillus fumigatus and Aspergillus flavus. Other samples which have shown activity were Cl-2, where activity was observed for Candida krusei, Aspergillus fumigatus and Trichophyton interdigitale strains, Cl-3 for...
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In vitro screening of novel potentially active antibacterial compounds
Davidová, Lucie ; Janďourek, Ondřej (advisor) ; Konečná, Klára (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Study program: Specialist in Laboratory Methods Candidate: Bc. Lucie Davidová Supervisor: PharmDr. Ondřej Janďourek, Ph.D. Title of diploma thesis: In vitro screening of novel potentially active antibacterial compounds. The diploma thesis deals with the antibiotics policy and is focused on resistance and mechanism of action of the antibiotics. A great attention is also paid to novel substances testing in terms of their impact on the selected bacteria. Theoretical part of thesis describes the system of antibiotic policy including its structure and organization in the Czech Republic. It also briefly summarizes this issue globally as well as individual organizations involved in the organization of the antibiotic policy. The theoretical part is also concerned with the history, classification, effects and significance of the antibiotics. A particular attention is paid to the chapter describing the macromolecular mechanism of action of 2 selected groups of substances (antibiotics) on bacteria, including physiological functions of some bacterial structures. And, last but not least, the theoretical part summarizes principles of bacterial resistance including its origin and development. The diploma thesis...
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Evaluation of activity of potentional antibacterial substances through the use of microdilution broth method
Švirlochová, Veronika ; Vejsová, Marcela (advisor) ; Janďourek, Ondřej (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Bc. Veronika Švirlochová Supervisor: Mgr. Marcela Vejsová, Ph.D. Diploma thesis title: Evaluation of activity of potentional antibacterial substances through the use of microdilution broth method Background The aim of this diploma thesis was to evaluate antibacterial activity of fifty-two newly synthetized substances. Methods Substances were tested through the use of microdilution broth method with eleven different concentrations. There were used eight bacterial strains and there were also used agents of nosocomial infections. Results Tested substancies were divided into seven groups by their chemical structure. The most effective group were sulphonamides. There were two groups with mininal or zero antibacterial activity. Conclusion The results showed that the most sensitive strain was Staphylococcus epidermidis and the least sensitive strain was Pseudomonas aeruginosa. There was also consideration about the presence of different substituents in different groups and their influence of antibacterial activity.
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Evaluation of activity of potentional antifungal substances through the use of microdilution broth method
Ťapuchová, Ivana ; Vejsová, Marcela (advisor) ; Konečná, Klára (referee)
Department of Biological and Medical Sciences Faculty of Pharmacy in Hradec Králové Charles University in Prague Author: Ivana Ťapuchová Title of diploma thesis: Evaluation of activity of potentional antifungal substances through the use of microdilution broth method Supervisor: Mgr. Marcela Vejsová, Ph.D. Background: The aim of this diploma thesis was to evaluate potential antifungal activity of 52 test substances which were develope at the Department of anorganic and organic chemistry Faculty of Pharmacy in Hradec Králové Charles University in Prague. Methods: For testing we used microdilution broth method on eight strains of yeasts and filamentous fungi in the laboratory of Department of Biological and Medical Sciences. Results: Overall 26 test substances with various substituents had antifungal activity. These substances was derivates of 4-aminobenzoic acid, 4-aminosalicylic acid, 5-aminosalicylic acid and large group derivates of sulfonamids. The most sensitive strain was dermatophyt Trichophyton mentagrophytes, the least sensitive strain was filamentous fungi Absidia corymbifera. Conclusions: Despite there was observed antifungal activity in low concentrations of derivates, it is necessary to perform next tests and clinical studies to prove efficiency and safety for use. Key words: yeasts,...
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Evaluation of activity of potentional antibiotic substances through the use of microdilution broth method II
Kopečná, Klára ; Konečná, Klára (advisor) ; Jílek, Petr (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of biological and medical sciences Study program: Pharmacy Autor: Klára Kopečná Supervisor: Mgr. Klára Konečná, Ph.D. Title of diploma thesis: Evaluation of activity of potencional antibiotic substances through the use of microdilution broth method II Background: To evaluate the antibacterial activity of the compounds synthesized by the Department of Pharmaceutical Chemistry and Drug control, Faculty of Pharmacy in Hradec Králové, Charles University in Prague under the leadership of prof. PharmDr. Martin Doležal, Ph.D. Methods: Using broth microdilution method was tested antibacterial activity at eight bacterial strains, namely Staphylococcus aureus, Staphylococcus aureus methicilin resistant, Staphylococcus epidermidis, Enterococcus sp., Escherichia coli, Klebsiella pneumoniae, Klebsiella pneumoniae ESBL positive and Pseudomonas aeruginosa. Results: Test substances were divided into 5 groups according to similarities in the chemical structure. The best antibacterial activity was observed in the group of derivatives of N-benzyl- 6-(alkylamino)pyrazine-2-carboxamide. Conclusion: Antibacterial activity was detected in 10 of 24 tested compounds. From active substances, all but one danced only Gram-positive bacteria. Among...
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Tyrosol effects on minimal inhibition concentration of ATM in Candida albicans
Vaisová, Marcela ; Křivčíková, Lucie (advisor) ; Blažíčková, Kateřina (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Author: Marcela Vaisová Supervisor: Lucie Křivčíková Title of diploma thesis: Effect of tyrosol on minimal inhibitory concentration of antimycotics Previous studies concerning quorum sensing in Candida albicans discovered two quorum sensing molecules, farnesol and tyrosol. Tyrosol has been formerly confirmed as a substance which shortens the lag phase of Candida albicans cell cycle and stimulates its conversion to the hyphal form, farnesol stimulates blastospores. This work covers the effect of tyrosol combined with two antimycotics, fungistatic fluconazole and fungicidal amphotericine B. Candida albicans strains used in the experiment were mostly isolated from samples taken from patients suffering from variously located Candida albicans infections and four laboratory standard strains were also used. The method used for the experiment was a modified broth dilution method using combinations of both tyrosol and antimycotics various concentrations, which were prepared by two-fold dilution. Using amphotericine B, 28 strains did not show any difference in MIC compared with the control sample, 6 strains showed mildly higher MIC and 3 strains shower mildly lower MIC. Using fluconazole, 24...
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Evaluation of activity of potentional antifungal substances through the use of microdilution broth method
Drnková, Nela ; Vejsová, Marcela (advisor) ; Konečná, Klára (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Bc. Nela Drnková Supervisor: Mgr. Marcela Vejsová, Ph.D. Title of diploma thesis: Evaluation of activity of potencial antifungal substances trought the use of microdilution broth method Background: The aim of this thesis was evaluation of antifungal activity of 70 substances trought the use of microdilution broth method. Substances for testing were synthesized at the Faculty of Pharmacy and they were divided into 5 groups based on chemical structure. Methods: The microdilution broth method was used for testing. The antifungal activity of substances was tested on 8 strains of yeasts and filamentous fungi: Candida albicans, C. tropicalis, C. glabrata, C. krusei, Trichosporon asahii, Aspergillus fumigatus, Absidia corymbifera a Trichophyton mentagrophytes. Results: The most active substances were in group of salicylanilide N- monosubstituted and N,N-disubstituted carbamates and thiocarbamates. The most effective substances were SAL-1L, SAL-1M, SAL-1N. They were effective on Trichophyton mentagrophytes already at concentration of 1,95 µmol.l-1 . The widest spectrum had substance GP-137, it inhibited the growth of all tested strains, but only at high concentrations. Rhodamine...
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Evaluation of activity of potentional antimycotic substances through the use of microdilution broth method III
Zavřelová, Alena ; Konečná, Klára (advisor) ; Němečková, Ivana (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Title of thesis: Evalution of activity of potentional antimycotic substances through the use of microdilution broth method III Autor of thesis: Alena Zavřelová Supervisor: Mgr. Klára Konečná, Ph.D. Background: The aim of this thesis, due to the growing incidence of fungal diseases and the growing incidence of resistance, was to determine the activity of potentially antimycotic active substances. We tested newly synthesized compoused, structurally based on the substance of pyrazinamide which is significant antituberculotic. Methods: Testing of substances was carried out using a broth microdilution method on eight strains of pathogenic fungi consisting of five yeast strains: Candida albicans, Candida tropicalis, Candida krusei, Candida glabrata, Trichosporon asahii and three strains of filamentous fungi: Aspergillus fumigatus, Absidia corymbifera, Trichophyton mentagrophytes. Results: From the range of tested concentrations and from the total number of the thirty tested substances, the most noticeable antifungal aktivity was revealed in the substance of 5-methyl-6-(2-phenylhydrazinyl)pyrazine-2,3- dicarbonitrile. All strains, except Trichophyton mentagrophytes strain, showed a relatively...
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