Pozměňování či falzifikace psaných textů jsou bezesporu staré jako sám vynález písma. Důvody pro takové jednání byly různé, nicméně skutečné stáří, respektive autenticita, daného rukopisu mají velký dopad na jeho význam, ať již pro historii, nebo - v případě současných rukopisů - z hlediska právního. U některých historických rukopisů je otázka jejich datování řešena s použitím spektroskopických technik, jejichž hlavní výhodou je nedestruktivnost nebo minimální invazivnost, neohrožující samu existenci zkoumaného dokumentu. V článku jsou zmíněny nejčastější spektroskopické metody používané k těmto účelům, včetně příkladů konkrétních studovaných rukopisů., The alteration or falsification of written texts is undoubtedly old as invention of scripture itself. The reasons for such behaviour are different, but the actual age or authenticity of the manuscript had a great impact on its signification, whether for history or, in the case of contemporary manuscripts, from a legal point of view. For historical manuscripts, the question of their dating is solved using spectroscopic techniques whose main advantage is non-destructiveness or minimal invasiveness, not endangering the very existence of the document under study. In the article the most frequent spectroscopic methods used for these purposes are mentioned and examples of particular studied manuscripts are given., Karel Nesměrák., and Obsahuje bibliografické odkazy
Genes encoding enzymes involved in fatty acids (FA) and glucose oxidation are transcriptionally regulated by peroxisome proliferator-activated receptors (PPAR), members of the nuclear receptor superfamily. Under conditions associated with O 2 deficiency, PPAR-α modulates substrate switch (between FA and glucose) aimed at the adequate energy production to maintain basic cardiac function. Both, positive and negative effects of PPAR-α activation on myoc ardial ischemia/reperfusion (I/R) injury have been reported. Moreover, the role of PPAR-mediated metabolic shifts in cardioprotective mechanisms of preconditioning (PC) is relatively less investigated. We explored the effects of PPAR-α upregulation mimicking a delayed “second window” of PC on I/R injury in the rat heart and potential downstream mechanisms involved. Pretreatment of rats with PPAR-α agonist WY-14643 (WY, 1 mg/kg, i.p.) 24 h prior to I/R reduced post-ischemic stunning, arrhythmias and the extent of lethal injury (infarct size) and ap optosis (caspase-3 expression) in isolated hearts exposed to 30-min global ischemia and 2-h reperfusion. Protection was associated with remarkably increased expression of PPAR- α target genes promoting FA utilization (medium-chain acyl-CoA de hydrogenase, pyruvate dehydrogenase kinase-4 and carnitine palmitoyltransferase I) and reduced expression of glucose transporter GLUT-4 responsible for glucose transport and metabolism. In addition, enhanced Akt phosphorylation and protein levels of eNOS, in conjunction with blunting of cardioprotection by NOS inhibitor L-NAME, were observed in the WY-treated hearts. Conclusions: upregulation of PPAR-α target metabolic genes involved in FA oxidation may underlie a delayed phase PC-like protection in the rat heart. Potential non-genomic effects of PPAR-α-mediated cardioprotection may involve activation of prosurvival PI3K/Akt pathway and its downstream targets such as eNOS and subsequently reduced apoptosis., T. Ravingerová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
During the medieval and early modern eras, most of the European urban authorities intended to rule their cities for the «common good», together with respecting the social hierarchy and privileged status. In the 18th century, however, many voices raised for improving the urban policing and reforming old regulations. Most of police officers claimed for equality of every inhabitant with regards to local police ordinances and petty police courts. But even if the urban rules agreed with their arguments for a more efficient policing, they could not prescribe an equality that would overthrow the Ancien Régime’s social order. Brussels in the 18th century is a good example of this contradiction. It was there impossible to reform the policing for the foreigners nor to create a professional night-watch, because of the strong reluctance of the city aldermen to abandon social privileges which were seen as fundamental freedoms of the country., Catherine Denys ; translated by Laura Bennett., and Obsahuje bibliografické odkazy
Studies have shown that uridine concentration in plasma may be an indicator of uric acid production in patients with gout. It has been also postulated that uridine takes part in blood pressure regulation. Since physical exercise is an effective tool in treatment and prevention of cardio-vascular diseases that are often accompanied by hyperuricemia and hypertension, it seemed advisable to attempt to evaluate the relationship between oxypurine concentrations (Hyp, Xan and UA) and that of Urd and BP after physical exercise in healthy subjects. Sixty healthy men (17.2±1.71 years, BMI 23.2±2.31 kg m-2, VO2max 54.7±6.48 ml kg-1 min-1) took part in the study. The subjects performed a single maximal physical exercise on a bicycle ergometer. Blood for analyses was sampled three times: immediately before exercise, immediately after exercise, and in the 30th min of rest. Concentrations of uridine and hypoxanthine, xanthine and uric acid were determined in whole blood using high-performance liquid chromatography. We have shown in this study that the maximal exercise-induced increase of uridine concentration correlates with the post-exercise increase of uric acid concentration and systolic blood pressure. The results of our study show a relationship between uridine concentration in blood and uric acid concentration and blood pressure. We have been the first to demonstrate that a maximal exercise-induced increase in uridine concentration is correlated with the post-exercise and recovery-continued increase of uric acid concentration in healthy subjects. Thus, it appears that uridine may be an indicator of post-exercise hyperuricemia and blood pressure., W. Dudzinska, A. Lubkowska, B. Dolegowska, M. Suska, M. Janiak., and Obsahuje bibliografii
The hyperinsulinemic euglycemic clamp (HEC) combined with indirect calorimetry (IC) is used for estimation of insulin-stimulated substrate utilization. Calculations are based on urinary urea nitrogen excretion (UE), which is influenced by correct urine collection. The aims of our study were to improve the timing of urine collection during the clamp and to test the effect of insulin on UE in patients with type 1 diabetes (DM1; n=11) and healthy subjects (C; n=11). Urine samples were collected (a) over 24 h divided into 3-h periods and (b) before and during two-step clamp (1 and 10 mIU.kg-1.min-1; period 1 and period 2) combined with IC. The UE during the clamp was corrected for changes in urea pool size (UEc). There were no significant differences in 24-h UE between C and DM1 and no circadian variation in UE in either group. During the clamp, serum urea decreased significantly in both groups (p<0.01). Therefore, UEc was significantly lower as compared to UE not adjusted for changes in urea pool size both in C (p<0.001) and DM1 (p<0.001). While UE did not change during the clamp, UEc decreased significantly in both groups (p<0.01). UEc during the clamp was significantly higher in DM1 compared to C both in period 1 (p<0.05) and period 2 (p<0.01). The UE over 24 h and UEc during the clamp were statistically different in both C and DM1. We conclude that urine collection performed during the clamp with UE adjusted for changes in urea pool size is the most suitable technique for measuring substrate utilization during the clamp both in DM1 and C. Urine collections during the clamp cannot be replaced either by 24-h sampling (periods I-VII) or by a single 24-h urine collection. Attenuated insulin-induced decrease in UEc in DM1 implicates the impaired insulin effect on proteolysis. and Obsahuje bibliografii a bibliografické odkazy