Novel KCNQ1 mutations in patients after myocardial infarction

Background: Patients after myocardial infarction (MI) are at greater risk of sudden cardiac death (SCD) than people in the overall population. The aim of this study was to detect mutations, including intronic ones, in the KCNQ1 gene coding for proteins of cardiac potassium channels and evaluate their possible effects on the clinical course in patients after MI. Methods: The study group was composed of 100 Polish patients after MI, which included 27 women (mean age 69 years) and 73 men (mean age 67 years). All patients underwent clinical examinations and genetic tests. The genetic test results have been correlated with the clinical data. The following parameters have been chosen as endpoints for this survey: sudden cardiac arrest (SCA) or SCD, complex ventricular arrhythmia, QT interval and QT dispersion values assessed during 24-hour Holter ECG monitoring in relation to ventricular arrhythmias as well as the minimum and maximum heart rate (HR) observed during the examination. Results: Six new mutations in the KCNQ1 gene: C2505734T, A2753831C in exons and C2505846A, G2753881A, T2755854C, T2755875G in introns. Detected intronic mutations in patients after MI were related to a worse clinical course and frequent occurrence of SCA. Conclusions: The novel intronic mutations may have a significant influence on the clinical course of the disease. (Cardiol J 2008; 15: 252-260

Novel organic material induced by electron beam irradiation for medical application

This study analyzed the e ects of irradiation of polytetrafluoroethylene (PTFE) containing 40% of bronze using an electron beam with energy of 10 MeV. Dosages from 26 to156 kGy (2.6–15.6 Mrad) were used. The impact of a high-energy electron beam on the thermal, spectrophotometric, mechanical, and tribological properties was determined, and the results were compared with those obtained for pure PTFE. Thermal properties studies showed that such irradiation caused changes in melting temperature Tm and crystallization temperature Tc, an increase in crystallization heat DHc, and a large increase in crystallinity c proportional to the absorbed dose for both polymers. The addition of bronze decreased the degree of crystallinity of PTFE by twofold. Infrared spectroscopy (FTIR) studies confirmed that the main phenomenon associated with electron beam irradiation was the photodegradation of the polymer chains for both PTFE containing bronze and pure PTFE. This had a direct e ect on the increase in the degree of crystallinity observed in DSC studies. The use of a bronze additive could lead to energy dissipation over the additive particles. An increase in hardness H and Young’s modulus E was also observed. The addition of bronze and the irradiation with an electron beam improved of the operational properties of PTFE

Tribological and Mechanical Behavior of Graphite Composites of Polytetrafluoroethylene (PTFE) Irradiated by the Electron Beam

This research investigated the e ect of irradiation with an electron beam energy of 10 MeV in doses of 26–156 kGy on polytetrafluoroethylene (PTFE) with a 15% and 20% graphite additive. The research has shown that mechanical (compression strength, hardness, and Young’s modulus) and sclerometric (coe cient of wear micromechanism and coe cient of resistance to wear) properties improve and tribological wear decreases as graphite content increases. Electron beam irradiation increases the degree of crystallinity of both materials to a similar extent. However significant di erences in the improvement of all examined properties have been demonstrated for PTFE with higher (20%) graphite content subjected to the electron beam irradiation. This polymer is characterized by higher hardness and Young’s modulus, reduced susceptibility to permanent deformation, higher elasticity, compression strength, and above all, a nearly 30% reduction in tribological wear compared to PTFE with a 15% graphite additive. The most advantageous properties can be obtained for both of the examined composites after absorbing a dose of 104 kGy. The obtained results hold promise for the improvement of the operational life of friction couples which do not require lubrication, used for example in air compressors and engines, and for the possibility of application of these modified polymers. In particular PTFE with 20% graphite content, in the nuclear and space industry

The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts

The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts. June 4-7, 2019, Szczyrk, Polan

Tribological and mechanical behavior of graphite composites of Polytetrafluoroethylene (PTFE) irradiated by the electron beam

This research investigated the effect of irradiation with an electron beam energy of 10 MeV in doses of 26-156 kGy on polytetrafluoroethylene (PTFE) with a 15% and 20% graphite additive. The research has shown that mechanical (compression strength, hardness, and Young's modulus) and sclerometric (coefficient of wear micromechanism and coefficient of resistance to wear) properties improve and tribological wear decreases as graphite content increases. Electron beam irradiation increases the degree of crystallinity of both materials to a similar extent. However significant differences in the improvement of all examined properties have been demonstrated for PTFE with higher (20%) graphite content subjected to the electron beam irradiation. This polymer is characterized by higher hardness and Young's modulus, reduced susceptibility to permanent deformation, higher elasticity, compression strength, and above all, a nearly 30% reduction in tribological wear compared to PTFE with a 15% graphite additive. The most advantageous properties can be obtained for both of the examined composites after absorbing a dose of 104 kGy. The obtained results hold promise for the improvement of the operational life of friction couples which do not require lubrication, used for example in air compressors and engines, and for the possibility of application of these modified polymers. In particular PTFE with 20% graphite content, in the nuclear and space industry

The Inhibitory Potential of Selected Essential Oils on Fusarium spp. Growth and Mycotoxins Biosynthesis in Maize Seeds

Owing to their rich chemical composition, essential oils (EOs) have many interesting properties, including antimicrobial activities. The presence of Fusarium and their secondary metabolites, mycotoxins, in cereal crops is a serious problem in agriculture, which consequently affects food quality. The aim of the present study was to investigate the effects of selected EOs on the growth of Fusarium graminearum and F. culmorum and the biosynthesis of mycotoxins in maize seeds. Chromatographic analysis of ergosterol as a fungal growth indicator showed a significant inhibition of Fusarium growth (83.24–99.99%) compared to the control samples, which as a consequence resulted in a reduction in mycotoxin concentrations. The addition of cinnamon, palmarosa, orange, and spearmint EOs was shown to be the most effective in reducing zearalenone concentration (99.10–99.92%). Deoxynivalenol analysis confirmed a very high reduction of this compound at the application all tested EOs (90.69–100%). The obtained results indicated that EOs have a great potential to inhibit growth of Fusarium fungi as well as reduce the concentration of mycotoxins in maize seed

Degradation of zearalenone by essential oils under in vitro conditions

Essential oils are volatile compounds, extracted from plants, which have a strong odour. These compounds are known for their antibacterial and antifungal properties. However, data concerning degradation of mycotoxins by these metabolites are very limited. The aim of the present study was to investigate the effect of essential oils (cedarwood, cinnamon leaf, cinnamon bark, white grapefruit, pink grapefruit, lemon, eucalyptus, palmarosa, mint, thymic and rosemary) on zearalenone reduction under various in vitro conditions, including the influence of temperature, pH, incubation time and mycotoxin and essential oil concentrations. The degree of zearalenone reduction was determined by HPLC method. It was found that the kind of essential oil influences the effectiveness of toxin level reduction, the highest being observed for lemon, grapefruit, eucalyptus and palmarosa oils, while lavender, thymic and rosemary oils did not degrade the toxin. In addition, the decrease in zearalenone content was temperature, pH as well as toxin and essential oil concentration dependent. Generally, higher reduction was observed at higher temperature in a wide range of pH, with clear evidence that the degradation rate increased gradually with time. In some combinations (e.g. palmarosa oil at pH 6 and 4 or 20C) a toxin degradation rate higher than 99% was observed. It was concluded that some of the tested essential oils may be effective in detoxification of zearalenone.We suggested that essential oils should be recognized as an interesting and effective means of zearalenone decontamination and/or detoxification

Artykuł oryginalnyZwiązek pomiędzy polimorfizmami w genach SCN5A, KCNQ1 i KCNE1 a złożonymi komorowymi zaburzeniami rytmu u chorych po zawale serca

Background: Post-MI patients are highly susceptible to sudden cardiac arrest (SCA) and sudden cardiac death (SCD) resulting from ventricular arrhythmia (VA). The search for new clinical predictors to identify those patients who are at the highest risk of these events is therefore essential. Numerous data indicate that the presence of polymorphisms and mutations in the cardiac ion channel genes SCN5A, KCNQ1 and KCNE1 might serve as such a predictor. Since genetic alterations in these genes underlie congenital long QT syndrome (LQTS), which is associated with an increased occurrence of arrhythmic complications and SCD, we decided to verify how alterations in these genes contribute to QT interval abnormalities and consequently to VA, SCA and SCD in post-MI patients. Aim: To detect single nucleotide polymorphisms (SNP) in SCN5A, KCNQ1 and KCNE1 of post-MI patients, and to assess whether they are related to electrophysiological markers of cardiac arrhythmia (QT interval) and the clinical course. Method: The study group consisted of 100 patients (27 females, mean age 69 years) with documented MI 3 months before enrolment. All patients underwent baseline and (after 12 months) control examinations encompassing history, physical examination, basic laboratory analysis, resting 12-lead ECG, 24-hour 12-lead Holter ECG monitoring and echocardiography. Genetic tests were performed during baseline examination. Results: In post-MI patients two exonic polymorphisms, H558R in SCN5A and S38G in KCNE1, and two intronic ones, in KCNQ1, were detected. H558R was associated with an increase in QT dispersion (QTd) at minimum and maximum heart rate and QT interval prolongation before premature ventricular beats (PVB), whereas S38G and intronic polymorphisms were related to an increase in QTd before PVB. None of the above polymorphisms was related to complex VA, SCA or SCD. Conclusion: The above polymorphisms were associated with abnormal repolarisation phase patterns in post-MI patients, which manifested in QT interval prolongation and QTd increase. There was no relationship between these polymorphisms and complex VA, SCA or SCD. The results show that not only exonic alterations but also intronic ones may affect the phenotype.Wstęp: Wysokie zagrożenie nagłym zatrzymaniem krążenia (NZK) i nagłym zgonem sercowym (NZS), u podłoża którego leżą groźne komorowe zaburzenia rytmu (KZR), u chorych po zawale serca skłania do poszukiwania nowych wskaźników klinicznych, które z dużym prawdopodobieństwem pozwoliłyby na wyodrębnienie spośród nich osób o najwyższym ryzyku tych zdarzeń sercowych. Coraz więcej doniesień wskazuje, że obecność mutacji i polimorfizmów w genach sercowych kanałów jonowych SCN5A i KCNQ1, KCNE1 może stanowić właśnie taki wskaźnik. Ponieważ zmiany w tych genach mogą powodować wrodzone zespoły wydłużonego odstępu QT, który związany jest ze zwiększoną częstością występowania powikłań arytmicznych i NZS, postanowiono sprawdzić, w jakim stopniu zmiany w tych genach przyczyniają się do nieprawidłowości odstępu QT, a tym samym złożonych KZR, NZK i NZS u chorych po zawale serca. Cel: Celem badania w tej grupie chorych było poszukiwanie zmian w genotypie w postaci polimorfizmów pojedynczych nukleotydów (ang. single nucleotide polymorphism, SNP) w genach SCN5A, KCNQ1 i KCNE1. Następnie ocena, czy stwierdzone zaburzenia genetyczne mają związek z elektrofizjologicznym markerem ryzyka zaburzeń rytmu serca, jak odstęp QT, oraz ocena związku pomiędzy stwierdzonymi zmianami w genotypie a klinicznym przebiegiem choroby: złożonymi KZR, NZK i NZS. Dodatkowo sprawdzano, czy zmiany w intronach genów mogą wpływać na przebieg kliniczny. Metodyka: Badaniem objęto 100 osób z populacji polskiej z udokumentowanym przebytym co najmniej przed 3 mies. zawałem serca. U wszystkich pacjentów przeprowadzono badanie wstępne i po 12 mies. kontrolne. Obejmowały one wywiad, badanie przedmiotowe, podstawowe badania laboratoryjne, spoczynkowe badanie EKG, 24-godzinne monitorowanie EKG metodą Holtera oraz badanie echokardiograficzne. W okresie badań wstępnych wykonano badania genetyczne. W analizie statystycznej korelowano dane genetyczne z danymi klinicznymi. Wyniki: U chorych po zawale serca w egzonach: genu SCN5A wykryto polimorfizm H558R, genu KCNE1 – S38G, natomiast w intronach genu KCNQ1 dwa polimorfizmy. Polimorfizm H558R związany był ze zwiększoną dyspersją QT w czasie wolnych i szybkich rytmów serca i z wydłużeniem odstępu QT przed przedwczesnymi pobudzeniami komorowymi, podczas gdy polimorfizmy S38G i intronowe ze zwiększoną dyspersją QT przed przedwczesnymi pobudzeniami komorowymi. Żaden z powyższych polimorfizmów nie był związany ze złożonymi KZR, NZK i NZS. Wnioski: Powyższe polimorfizmy u chorych po zawale serca związane były z nieprawidłowym przebiegiem fazy repolaryzacji, czego najwyraźniejszym przejawem było wydłużanie się odstępu QT i zwiększenie dyspersji QT. Nie wykazano związku polimorfizmów w tych genach ze złożonymi KZR, NZK ani NZS. Uzyskane wyniki wskazują, że nie tylko zmiany w egzonach, ale i w intronach mogą mieć wpływ na fenotyp

The Concentration-Dependent Effects of Essential Oils on the Growth of Fusarium graminearum and Mycotoxins Biosynthesis in Wheat and Maize Grain

The presence of Fusarium fungi and their toxic metabolites in agricultural crops contributes to significant quantitative and qualitative losses of crops, causing a direct threat to human and animal health and life. Modern strategies for reducing the level of fungi and mycotoxins in the food chain tend to rely on natural methods, including plant substances. Essential oils (EOs), due to their complex chemical composition, show high biological activity, including fungistatic properties, which means that they exhibit high potential as a biological plant protection factor. The aim of this study was to determine the fungistatic activity of three EOs against F. graminearum, and the reduction of mycotoxin biosynthesis in corn and wheat grain. All tested EOs effectively suppressed the growth of F. graminearum in concentrations of 5% and 10%. Cinnamon and verbena EOs also effectively reduced the ergosterol (ERG) content in both grains at the concentration of 1%, while at the 0.1% EO concentration, the reduction in the ERG amount depended on the EO type as well as on the grain. The degree of zearalenone (ZEA) reduction was consistent with the inhibition of ERG biosynthesis, while the reduction in deoxynivalenol (DON) was not consistent with this parameter

The Concentration-Dependent Effects of Essential Oils on the Growth of <i>Fusarium graminearum</i> and Mycotoxins Biosynthesis in Wheat and Maize Grain

The presence of Fusarium fungi and their toxic metabolites in agricultural crops contributes to significant quantitative and qualitative losses of crops, causing a direct threat to human and animal health and life. Modern strategies for reducing the level of fungi and mycotoxins in the food chain tend to rely on natural methods, including plant substances. Essential oils (EOs), due to their complex chemical composition, show high biological activity, including fungistatic properties, which means that they exhibit high potential as a biological plant protection factor. The aim of this study was to determine the fungistatic activity of three EOs against F. graminearum, and the reduction of mycotoxin biosynthesis in corn and wheat grain. All tested EOs effectively suppressed the growth of F. graminearum in concentrations of 5% and 10%. Cinnamon and verbena EOs also effectively reduced the ergosterol (ERG) content in both grains at the concentration of 1%, while at the 0.1% EO concentration, the reduction in the ERG amount depended on the EO type as well as on the grain. The degree of zearalenone (ZEA) reduction was consistent with the inhibition of ERG biosynthesis, while the reduction in deoxynivalenol (DON) was not consistent with this parameter