While the presence of ≥1% of an undeclared species in ground meat generally used as an indicator of intentional mislabeling as opposed to cross-contamination, the actual percent of undeclared species resulting from cross-contamination has not been experimentally determined. The objective of this study was to quantify the effect of sanitation procedures on the crosscontamination of animal species in ground meat products, using undeclared pork in ground beef. Pork (13.6 kg) was processed using a commercial grinder, then one of three sanitation treatments was completed (“no cleaning”, “partial cleaning”, or “complete cleaning”). Next, beef (13.6 kg) was ground using the same equipment. For “no cleaning,” beef was ground immediately after pork without any cleaning step; for “partial cleaning,” the hopper tray was wiped, and excess meat was taken out from the auger; for “complete cleaning,” all parts of the grinder were disassembled and thoroughly cleaned with water and soap. A 100-g sample was collected for each 0.91 kg (2 lb) of beef processed with the grinder and each sanitation treatment was tested twice. Real-time polymerase chain reaction (PCR) was used to quantify pork in ground beef. For “no cleaning,” the first 100-g sample of ground beef run through the grinder contained 24.42 ± 10.41% pork, while subsequent samples contained

Adaptation to chronic hypoxia provides myocardial protection against ischemia - reperfusion injury (IR). Cardioprotective effect of adaptation depends on the degree and duration of hypoxic exposure and daily regime of adaptation. Certain protective regimes of adaptations to hypoxia have been reported to activate proapoptotic signaling pathways and bioactive sphingolipids were recently shown to play important role in the regulation of apoptosis in the heart. We aimed to determine the mRNA level of selected genes related to apoptotic pathways and to sphingolipid metabolism in two models of hypoxic adaptation, continous normobaric hypoxia (CNH 10% O2) with different exposures (4h, 48h, 120h, 21days) and intermitent hypobaric hypoxia (IHH 7000 m, 8h/day). Both ventricles, LV and RV, were analysed after adaptation to CNH and only LV was analysed after IHH adaptation. Our results show that both types of adaptation increased mRNA of proapoptotic genes, CNH mainly in RV and IHH in LV. Furthermore, increased expressions of proapoptotic genes were accompanied by the increase of expression of enzymes producing predominantly protective kinds of sphingolipids. The exact role of apoptosis and sphingolipid signaling molecules in endogenous myocardial protection requires further research. Key words: Apoptosis,...

Introduction: Methamphetamine is a drug frequently abused by drug-addicted pregnant women and also one of the mostcommonly used drugs in the CzechRepublic. This drug passes easily through a placental barrier into the fetus. Thus it can negatively affect not only the mother but also the prenatal development of her offspring. Objectives: In the framework of the grant project GA CR: 14-03708S, the long-term effects of prenatal exposure to methamphetamine were detected. It was determined whether the prenatal methamphetamine exposure affects the generation of offspring of exposed females at the level of gene expression of genes in specific regions of the brain, striatum, hippocampus and prefrontal cortex. Methods: In the selected parts of the brain, which were removed from the rat, the microarray hybridization and the real-time PCR to express changes in expression of selected genes were performed. Results: Statistical analysis of microarray hybridization did not show the significantly altered gene expression in tested genes significantly. Only boundary values for 13 genes were measured, which were further tested by real-time PCR.After a statistic evaluation of real-time PCR, the significantly altered expression was found in 2 genes. The significantly changed expression of DRD3 and TACR3 genes was found...

Toxoplasma gondii is cosmopolitly living parasite which prevalence in human extends to tens of percent. In its life cycle it uses any homoiothermic vertebrate as an intermediate host. The definitive host are felines from Felidae family. The acute phase of infection is medically important in immunocompromised pacients and by its risk of congenital toxoplasmosis in pregnant women who never suffered from this illness before. Infection could have serious and rarely even lethal consequences in both cases. This thesis focuses on experimental verification of theory of sexual transmission of toxoplasmosis from male to female on laboratory mice. Possible transmission was tested in acute phase and latent phase of infection. The result was negative in both cases. Moreover, we observed the parasite's affinity to tissue of organs in male mice by PCR technique. Particularly, our interest was in comparing genital organs with others. It was discovered that lungs and spleen are the most infected organs in acute phase of infection. Toxoplasma was also present in genital organs (especially in epididymis) but not more frequently than in others. We observed statistically significant difference between sexual and non-sexual organs in acute and latent toxoplasmosis - non-sexual organs were more infected in both phases....

Introduction: Methamphetamine is a drug frequently taken by drug-addicted pregnant women and happens to be one of the most commonly used drugs in the Czech Republic. This drug passes easily through a placental barrier into the fetus. Thus it can negatively affect not only the mother but also the prenatal development of her offspring. Objectives: This research aims to provide a general screening of gene expression in selected regions of the F1 generation of the brain prenatally affected by methamphetamine, to verify whether exposure to methamphetamine affects the generation of offspring of exposed females at the level of gene expression in selected regions of the brain, and to valuate possible changes in gene expression. Methods: In selected parts of the brain, collected from a rat, the microarray hybridization and the real-time PCR were set to evaluate express changes in the expression of selected genes. Results: Statistical analysis of the microarray hybridization did not show a significantly altered gene expression in the tested genes. Only boundary values for 13 genes were measured, which were further tested by the real-time PCR. After a statistic evaluation of the real-time PCR, the significantly altered expression was found in 2 genes. The notably changed expression of DRD3 and TACR3 genes...

The topic of this thesis is focused on the testing of resistance of selected Brassica species to the black rot infection and viral mosaics caused by economically important pathogens of Brassicaceae family. The theoretical part describes characteristics of causal pathogens - Xanthomonas campestris pv. campestris (Xcc), Turnip mosaic virus (TuMV) and Turnip yellow mosaic virus (TYMV), and summarize the current state of a resistance study of these pathogens in the Brassicaceae family. The thesis also describes modern molecular methods used for the detection of bacterial and viral pathogens. In the experimental part, the detections of Xcc, TuMV and TYMV pathogens were optimized by PCR and RT-PCR. For bacterium Xcc, the Real-time PCR targeting a part of the zur gene sequence was designed using a TaqMan® probe. This detection system was subsequently processed in the form of a certified methodology for use in diagnostics. To increase the specificity, Real-time PCR targeting zur gene was involved in the Multiplex Real time PCR reaction. Then the dynamics of the Xcc infection was monitored in 6 hybrid cabbage cultivars. The testing of resistance to the black rot disease was optimized by the procedure including artificial inoculations using the suspension of the Xcc isolates HRIW 3811, 3971A and 1279A and the SU1 isolate originated from the Czech Republic. In a four-year experiment, the total of 42 homozygous breeding lines and 4 hybrid cultivars were tested, where 5 lines were recommended for breeding for resistance to the black rot disease. For the detection of TuMV and TYMV viruses, Real-time RT-PCR approaches based on the TaqMan® probe and SYBR Green dye were tested. The target region of both detections was the coat protein. The TuMV detection has been optimized for SYBR Green approach; for the TYMV detection, the use of the TaqMan® probe has been recommended. Detection systems were used to evaluate artificial inoculations of 6 cabbage cultivars by individual viruses. The tested plants did not show visual symptoms of infection therefore the presence of viruses was evaluated by Real-time RT PCR. The system designed for TYMV detected the presence of virus in all tested samples, TuMV was detected only in two samples. Negative detection results are probably in connection with the absence of TuMV symptoms which indicates unsuccesful plant inoculation. For both detection systems, it was recommended the verification on a wider range of viral isolates prior to standard use in diagnostics

Amoebic dysenteri is a problem in developing countries and is caused by Entamoeba histolytica (E. histolytica) with symptoms such as diarrhea, vomiting and in worse case extra intestinal manifestation. Currently there are difficulties to diagnose E. histolytica infections in developing countries because PCR requires advanced and expensive and microscopy cannot distinguish E. histolytica from other harmless species of amoebas. The aim of this study was therefore to develop loop-mediated isothermal amplification (LAMP), which is similar to PCR but is performed at a single temperature and amplifies the target gene in less than an hour. LAMP was also compared to real time PCR. With a commercial kit, DNA were extracted from cultivated trophozoites and for the LAMP reaction, a colorimetric mastermix and six primers were used designed from 18S small subunit ribosomal RNA gene. With phenol red positive LAMP reactions showed a color change from pink to yellow and negative LAMP reactions remained pink. The sensitivity of LAMP for detection of E. histolytica was determined to be 80 pg/µl, which was ten times less sensitive than real time-PCR. The method was also shown to work on trophozoites with no DNA extraction and no non-specific amplifications were seen with DNA from G. lamblia, which showed some specificity. LAMP proved to be sensitive and easy to work with, but requires tightly closed tubes to avoid contamination and false positive results. To develop and evaluate the method LAMP for detection of E. histolytica, more studies are needed, including clinical samples and optimization.

Respiratory tract infections are caused by different types of virus and bacteria and have become a global health issue. The detection and analysis of respiratory tract pathogens is nowadays performed commonly using PCR technology because of its high sensitivity. The aim of this study was to compare the performance of a new instrument, Starlet IVD with Maglead 12gC for extraction of nucleic acid from respiratory tract samples prior to real time PCR analysis. Frozen positive samples and fresh negative samples from patients were analyzed for respiratory viruses and respiratory bacteria. The samples were extracted on both Starlet IVD and Maglead 12gC. Real time PCR analysis was performed after the extraction to compare the performance between both instruments. A total of 44 virus samples were analyzed with Allplex respiratory panel 2 and 61 bacteria samples analyzed with Allplex respiratory panel 4. The result has shown an acceptable agreement of the PCR analysis (> 95%) for both panels between instruments. Starlet IVD has a higher Ct value compared to Maglead 12gC which led to a variation of 7,1% ± 3,6% in Ct value for Respiratory panel 2 and 10,1 % ± 5,3 % for Respiratory panel 4.  In conclusion, Starlet IVD is an automated instrument that will reduce hand-on-time, the risk of errors and improve the work routine for a better quality of results. Regardless the poor Ct-value, the new instrument has been able to detect almost all respiratory pathogens in the samples.

It has been found in previous studies that there is a correlation between the placenta regulatory genes and the weight gain of the mother, Body Mass Index (BMI) as well as the birthweight of the fetus. When the mother gains weight / is overweight, this will affect the gene expression in the placenta, and in turn this triggers the weight gain of the fetus. The aim of the study was to investigate the correlation between the lipoprotein lipase gene and the mother's BMI, weight gain and the child's birth weight by extracting RNA from the placentas and analysing its quality and concentration. cDNA was generated from RNA using reverse transcription and gene expression was amplified using real-time PCR. The data from real-time PCR was used in the comparative Ct-method to calculate a 2˄(-ΔΔCt)-value which represents the RNA-level of the LPL-gene. Lastly this value was analysed by using the two-statistic methods, Pearson's rank correlation and Spearman's correlation, which showed that the value of the correlation coefficient for all the variables was close to the value of zero. The closer the value is to zero, the weaker the association becomes between the different variables. The correlation was 0.045, 0.112 and 0.044 for the child's birth weight, mother's BMI respective weight gain. The results from this study shows that there is no correlation between LPL and the mother's weight gain, BMI, or the child's birth weight.

Die Arbeit hatte zum Ziel, ein In-vitro-Infektionsmodell für den protozoären Durchfallerreger Cryptosporidium parvum zu optimieren und dahingehend zu testen, ob es für eine quantitative Beurteilung der Infektiosität von Kryptosporidienoozysten eingesetzt werden kann. Die verwendeten Oozysten wurden zuvor im Zuge einer Passagierung im Kalb vermehrt, aus dem Kot isoliert, aufgereinigt und zur Infektion einer humanen ileocaecalen Adenokarzinomzelllinie (HCT-8) verwendet Die Kultivierung erfolgte über 48 Stunden in Mikrotiterplatten mit jeweils 24 Kavitäten. Die DNA infizierter Zellen und nichtinfizierter Kontrollen wurde anschließend isoliert und die parasitenspezifische DNA in der real-time PCR quantifiziert. Die gewählten Primer-Sonden-Kombinationen erlaubten eine spezifische Amplifikation der Erreger-DNA. In der Optimierung wurden das Brilliant®QPCR Core Reagent Kit, der ABsoluteTMQPCR sowie zwei verschiedene Oligonukleotidkombinationen untersucht. Durch die Klonierung einer Sequenz im Target-Gen und die Herstellung einer Titrationsreihe aus dieser klonierten DNA gelang es, den für die Vergleichbarkeit unerlässlichen homogenen Standard zu gewinnen. Der In-vitro-Vitalitätsassay wurde außerdem auf seine praktische Anwendbarkeit hin geprüft. Es wurde einerseits eine Desinfektionsmittelprüfung mit Chlorokresol (Neopredisan®135-E), andererseits ein Versuch zur thermischen Inaktivierung, beide unter Nutzung dreier verschiedener C. parvum-Chargen (LE-06-Cp-05/0, LE-07-Cp-05/2 vom Isolat A, LE-06-Cp-05/2 vom Isolat B), vollzogen. Die Überbewertung der Infektiosität der Oozysten durch die Betrachtung der Exzystierung konnte anhand der parallel zur DNA-Quantifizierung ermittelten Exzystierungsraten gezeigt werden. Die Exzystierungshemmung lag in jedem Versuch deutlich unter den in der real-time PCR berechneten Inaktivierungsraten. Je nach verwendeter Oozystencharge lieferte die Desinfektion mit 4 % Neopredisan®135-E Inaktivierungsraten, die zwischen 90 und 100 % bei einstündiger Einwirkzeit lagen. Mit steigender Dauer der Inkubation stieg erwartungsgemäß auch der Grad der Inaktivierung. Die Anwendung der 1 %igen Verdünnung resultierte in einer deutlich gesteigerten Exzystierungsrate gegenüber der unbehandelten Kontrolle sowie in stark variierenden Inaktivierungsraten (24 - 91,5 %). Es konnte gezeigt werden, dass mit Neopredisan®135-E unter den gewählten Inkubationsbedingungen zwar eine gute, aber keine vollständige Inaktivierung der C. parvum-Oozysten erfolgt. Eine suboptimale Wirkung zeigte sich in einer hohen Varianz der Einzelmesswerte. Die Vitalitätsraten betrugen nach einstündiger Inkubation der Oozysten bei 38°C noch 100 %, nach 24 Stunden waren diese bereits auf 5 - 23 % abgesunken. Es scheint, als würden mesophile Verhältnisse die Exzystierung der Sporozoiten anregen und bei längerer Konditionierung eine Erschöpfung des Stoffwechsels der Entwicklungsstadien herbeiführen. Die Inaktivierungsrate bei 55°C lag zwischen 96 und 100 %. Bei thermophiler Konditionierung wurde in drei von sieben Fällen, nach der Inkubation in Neopredisan®135-E nur in einer der sieben Untersuchungen ein vollständiger Vitalitätsverlust beobachtet. Die vorgestellte Methode erwies sich als gut reproduzierbar, sensitiv und schnell. Die In-vitro-Kultivierung des Erregers C. parvum ließ sich mit der real-time PCR, welche eine absolute Quantifizierung erlaubte, gut in Einklang bringen. Die Verwendung der In-vitro-Kultur als lebendes System ließ eine gewisse Variabilität der Ergebnisse zwischen einzelnen Untersuchungen erwarten, die sich aber in einem akzeptablen Bereich bewegten. Eine weitere Optimierung im Sinne einer Sensitivitätssteigerung bei akzeptabler Störanfälligkeit und Variabilität ist anzustreben.