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6554. Does divine intervention violate laws of nature?

Creator:
Bergmann, Ralf B.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
causation, causal processes, probabilistic processes, laws of nature, equations of motion, divine action, miracles, příčina, kauzální procesy, pravděpodobnostní procesy, zákony přírody, pohybové rovnice, božské působení, and zázraky
Language:
Slovak
Description:
The present paper discusses processes in our world embedded in a dense net of causes and effects. The role of laws of nature is discussed using classical mechanics as an example to demonstrate that the behavior of objects is not determined by laws of nature on their own. Natural processes rather depend on the environment that implies forces and conditions under which these processes occur. These conditions are usually described in mathematical terms using suitable initial or boundary conditions or further constrains. This analysis may seem trivial but has an important consequence. Divine intervention appears not to violate natural laws, rather, new causes are introduced that lead to results that otherwise would not have occurred. A further consequence arises from the complexity of causal nets and the presence of probabilistic processes in our world as one may not be able to determine the causes that led to a certain effect., Příspěvek pojednává o procesech v našem světě v husté síti příčin a následků. Role zákonů přírody je diskutována pomocí klasické mechaniky jako příklad, který demonstruje, že chování objektů není samo o sobě určeno zákony přírody. Přírodní procesy spíše závisí na prostředí, které implikuje síly a podmínky, za kterých tyto procesy probíhají. Tyto podmínky jsou obvykle popsány v matematických termínech za použití vhodných počátečních nebo okrajových podmínek nebo dalších omezení. Tato analýza se může zdát triviální, ale má důležitý důsledek. Zdá se, že božské zásahy neporušují přírodní zákony, spíše se zavádějí nové příčiny, které vedou k výsledkům, ke kterým by jinak nedošlo., and Ralf B. Bergmann
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

6555. Does elevated CO2 protect photosynthesis from damage by high temperature via modifying leaf water status in maize seedlings?

Creator:
Qu, M. N., Bunce, J. A., and Shi, Z. S.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, oxid uhličitý, kukuřice, photosynthesis, carbon dioxide, heat stress, leaf water potential, net photosynthesis, stomatal conductance, vapor pressure deficit, maize, 2, and 581
Language:
Multiple languages
Description:
We hypothesized that decreased stomatal conductance (gs) at elevated CO2 might decrease transpiration (E), increase leaf water potential (ΨW), and thereby protect net photosynthesis rate (PN) from heat damage in maize (Zea mays L) seedlings. To separate long-term effects of elevated CO2, plants grew at either ambient CO2 or elevated CO2. During high-temperature treatment (HT) at 45°C for 15 min, leaves were exposed either to ambient CO2 (380 μmol mol-1) or to elevated CO2 (560 μmol mol-1). HT reduced PN by 25 to 38% across four CO2 combinations. However, the gs and E did not differ among all CO2 treatments during HT. After returning the leaf temperature to 35°C within 30 min, gs and E were the same or higher than the initial values. Leaf water potential (ΨW) was slightly lower at ambient CO2, but not at elevated CO2. This study highlighted that elevated CO2 failed in protecting PN from 45°C via decreasing gs and ΨW., M. N. Qu, J. A. Bunce, Z. S. Shi., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6556. Does exogenous melatonin influence the free radicals metabolism and pain sensation in rat?

Creator:
Pekárková, I., Parara, S., Václav Holeček, Stopka, P., Ladislav Trefil, Jaroslav Racek, and Richard Rokyta
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, melatonin, oxidační stres, bolest, stres (fyziologie), volné radikály, oxidative stress, pain, stress (physiology), free radicals, 14, and 612
Language:
English
Description:
Melatonin has been shown to play a role in antioxidative defence. We therefore studied its effect on oxidative damage to the rat cerebral cortex evoked by painful stimulation and immobilization-induced stress. Moreover, the effect of melatonin on chronic pain perception was examined. Rats were injected with either a high dose of melatonin (100 mg/kg i.p.) or a vehicle for five days and were subjected to painful stimulation or immobilization stress 30 min after the treatment. To determine the degree of oxidative stress, the levels of free radicals, thiobarbituric acid reactive substances (TBARS) as indicators of lipid peroxidation and glutathione peroxidase (GSHPx) were estimated in somatosensory cortex. Pain perception was measured by the tail-flick and plantar test. Melatonin reduced the level of TBARS previously increased by painful stimulation. Melatonin also exhibited a slight analgesic effect in those animals exposed to painful stimulation but its role in free radical scavenging did not contribute to this effect., I. Pekárková, S. Parara, V. Holeček, P. Stopka, L. Trefil, J. Racek, R. Rokyta., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6557. Does impedance measure a functional state of the body fat?

Creator:
Renata Větrovská, Zdeněk Vilikus, Klaschka, J., Zuzana Stránská, Štěpán Svačina, Šárka Svobodová, and Martin Matoulek
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, tělesné složení, obezita, body composition, obesity, DEXA, fat mass, anthropometric methods, fat tissue functional properties, 14, and 612
Language:
English
Description:
The aim was to compare methods of body fat measurement in different BMI groups. An additional aim was to discuss differences reflecting the structural and functional changes of fat tissue. The study group included 130 adult Caucasian women stratified by body mass index (BMI): 18-24.99 (n=30), 25-29.99 (n=26), 30-34.99 (n=33), 35-39.99 (n=30), and BMI ≥ 40 (n=11). Bioelectrical impedance was performed using Tanita TBF 410 GS, Bodystat 1500, and Omron BF 300. A caliper type Best was also applied. Correspondence of four methods with DEXA was assessed using the Bland-Altman and ANOVA analyses. Measurements by BIA were not si gnificantly different from DEXA up to BMI of 30, but DEXA significantly overestimated in the higher BMI subgroup by all three methods. Caliper measurement significantly underestimated DEXA in all BMI subgroups. BIA methods overestimated DEXA for the obese subjects. Tanita did statistically the best. The Caliper test appeared less preferable than the BIA methods, especially in the higher BMI subgroup. DEXA and Caliper measurements seem to be the best estimate of structural (anatomical) fat quantity. We hypothesize that BIA methods could also measure some other physiopathological conditions like inflammation, hydration or cell infiltration of fat., R: Větrovská, Z. Vilikus, J. Klaschka, Z. Stránská, Š. Svačina, Š. Svobodová, M. Matoulek., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6558. Does inhibition of aldose reductase contribute to the anti-inflammatory action of setipiprant ?

Creator:
Ballekova, J., Soltesova-Prnova, M., Magdaléna Májeková, and Stefek, M.
Format:
print, bez média, and svazek
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, astma, záněty, asthma, inflammations, setipiprant, aldose reductase inhibition, androgenic alopecia, 14, and 612
Language:
English
Description:
The aim of this study was to investigate aldose reductase inhibitory action of setipiprant as a potential additional mechanism contributing to its anti-inflammatory action. Aldose reductase activity was determined by spectrophotometric measuring of NADPH consumption. Setipiprant was found to inhibit aldose reductase/NADPH-mediated reduction of 4-hydroxynonenal, 4-hydroxynonenal glutathione and prostaglandin H2 substrates, all relevant to the process of inflammation. Molecular modeling simulations into the aldose reductase inhibitor binding site revealed an interaction pattern of setipiprant. Considering multifactorial etiology of inflammatory pathologies, it is suggested that, in addition to the antagonizing prostaglandin D2 receptor, inhibition of aldose reductase may contribute to the reported anti-inflammatory action of setipiprant., J. Ballekova, M. Soltesova-Prnova, M. Majekova, M. Stefek., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

6559. Does Magnesium Dysbalance Participate in the Development of Insulin Resistance in Early Stages of Renal Disease?

Creator:
Katarína Šebeková, Štefíková, K., Daniela Polakovičová, Viera Spustová, and Rastislav Dzúrik
Format:
print, bez média, and svazek
Type:
article, studie, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, 31P NMR spectroscopy, Erythrocyte, Magnesium, Insulin resistance, Obesity, Kidney Disease, 14, and 612
Language:
English
Description:
We investigated the potential role of magnesium (Mg) dysbalance in the pathogenesis of insulin resistance (IR) in patients with mildly-to-moderately decreased renal function (creatinine: 142.8±11.0 mmol/l). The data were compared to those of 8 age- and sex-matched healthy controls (CTRL). The standard oral glucose tolerance test (oGTT) was performed in 61 patients. Twenty-two patients were classified as IR according to their values on fasting and after-load immunoreactive insulin concentrations. Serum and total erythrocyte Mg (tErMg) (atomic absorption spectro-photometry) and free erythrocyte Mg (fErMg) concentrations (31P NMR spectroscopy) were determined prior to and two hours after the glucose load. Ten out of 39 insulin-sensitive (IS) patients, but only one out of 22 insulin-resistant (IR) patients, had a low basal fErMg concentration (<162.2 mmol/l, c2, p<0.01). IR patients had higher serum Mg, total erythrocyte Mg and bound erythrocyte Mg (bErMg) concentrations (both before and after glucose load) when compared with the IS group. Both groups responded to the glucose load with a significant decrease in serum Mg concentration (within the normal range), while the IR group also exhibited a decline in tErMg and bErMg. The mean sum of insulin needed to metabolize the same glucose load correlated positively with tErMg (r=0.545, p<0.01) and bErMg (r=0.560, p<0.01) in the IR patients. It is concluded that, at an early stage of renal dysfunction, IR is not associated with the decline in free erythrocyte Mg concentration, but the magnesium handling in red blood cells is altered., K. Šebeková, K. Štefíková, D. Polakovičová, V. Spustová, R. Dzúrik., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6560. Does neonatal brain ischemia induce schizophrenia-like behaviour in young adult rats?

Creator:
Hana Tejkalová, Kaiser, M., Jan Klaschka, and František Šťastný
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Biochemie. Molekulární biologie. Biofyzika, biochemie, neurochirurgie, schizofrenie, potkan, biochemistry, neurosurgery, schizophrenia, Rattus norvegicus, neonatal ischemia, prepulse inhibition, 2, and 577
Language:
English
Description:
Perinatal cerebral hypoxia represents a major cause of obstetric complications and the resulting transient oxygen deficiency might belong to early risk factors for schizophrenia. The aim of this study was to evaluate possible long-term behavioral changes induced by one hour of continuous bilateral common carotid artery occlusion in 12-day-old male rats. Post-ischemic behavioral disturbances were evaluated in social (play) behavior on postnatal day 22 (PND 22), open field test (PND 35 and 50) and prepulse inhibition of the acoustic startle reflex (PND 50). Transient ischemia in neonatal rats was not significantly altered in social dyadic interactions evaluated in pre-weaning pups, but resulted in enhanced locomotor activity in pubertal rats (PND 35) and impaired prepulse inhibition of the startle reflex in post- pubertal males (PND 50). These behavioral alterations suggest that perinatal hypoxic/ischemic insults may represent a risk factor for later manifestation of specific features relevant to schizophrenia in predisposed individuals., F. Tejkalová, M. Kaiser, J. Klaschka, F. Šťastný., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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