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1603. Capsazepine affects thermal preferences of the American cockroach (Blattodea: Blattidae)

Creator:
Maliszewska, Justyna and Tęgowska, Eugenia
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, švábovití, Blattidae, Blattodea, American cockroach, behavioural thermoregulation, capsaicin, capsazepine, TRPV, 2, and 59
Language:
English
Description:
Capsazepine is a competitive antagonist of capsaicin, a TRPV1 agonist responsible for the spicy taste of pepper. TRPV1 agonists and antagonists are known to affect mammalian body temperature, but their action on thermoregulation in insects is poorly known. In this study we evaluated the effect of capsazepine on the thermal preference of the American cockroach, Periplaneta americana using a thermal gradient. Our results revealed that capsazepine in submicromolar concentrations induces a preference for higher ambient temperatures when compared to the control insects. To assess whether capsazepine may act also as an antagonist of capsaicin in insects, we determined this insects' thermal behaviour when capsazepine was applied before capsaicin. The hypothermic response to capsaicin was clearly blocked by pre-treatment with capsazepine only in female American cockroaches. Our results indicate the involvement of structures functionally similar to TRPV1 in insect thermosensation., Justyna Maliszewska, Eugenia Tęgowska., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1604. Captopril Fails to Reverse Hypertrophy of the Left Ventricle Induced by Aortic Insufficiency in Rabbits

Creator:
Fedor Šimko, Václav Pelouch, and Ján Kyselovič
Format:
print, bez média, and svazek
Type:
article, studie, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, Aortic insufficiency, Hypertrophy regression, Fibrosis, Cardiac hypertrophy, 14, and 612
Language:
English
Description:
Angiotensin converting enzyme (ACE) inhibition has been reported to induce regression of hypertrophy in several models of hemodynamic pressure overload. The aim of the present study was to determine whether the ACE inhibitor captopril can reduce hypertrophy of the left ventricle induced by a chronic volume overload and modify collagen composition of the hypertrophied myocardium. Rabbits with four months lasting aortic insufficiency were divided into two groups: treated with captopril (20 mg/kg/day) for five weeks and treated with placebo. The respective control groups were represented by sham-operated animals. Aortic insufficiency induced a decrease of diastolic pressure, an increase of systolic and pulse pressure, hypertrophy of the left and right ventricle, and an increase of hydroxyproline content in the left ventricle without a change of hydroxyproline concentrations in either ventricle. Captopril treatment further enhanced pulse pressure by decreasing diastolic blood pressure. Hypertrophy of the left ventricle, hydroxyproline content and concentration in both ventricles were unaffected by captopril treatment. It is concluded that ACE inhibition did not reverse the left ventricular hypertrophy developed as a result of overload induced by aortic insufficiency. We suggest that mechanisms different from activation of the renin-angiotensin system may play a decisive role in the maintenance of hypertrophy in this particular model of volume hemodynamic overload., F. Šimko, V. Pelouch, J. Kyselovic., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1605. Captopril partially decreases the effect of H2S on rat blood pressure and inhibits H2S-induced nitric oxide release from S-nitrosoglutathione

Creator:
Drobná, M., Misak, A., Holland, T., Kristek, F., Grman, M., Tomasova, L., Berenyiova, A., Cacanyiova, S., and Ondrias, K.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, sulfan, oxid dusnatý, krevní tlak, srdeční rytmus, hydrogen sulphide, nitric oxide, blood pressure, heart rate, captopril, H2S, 14, and 612
Language:
English
Description:
We studied the effects of the H2S donor Na2S on the mean arterial blood pressure (MAP) and heart and breathing rates of anesthetized Wistar rats in the presence and absence of captopril. Bolus administration of Na2S (1-4 μmol/kg) into the right jugular vein transiently decreased heart and increased breathing rates; at 8-30 μmol/kg, Na2S had a biphasic effect, transiently decreasing and increasing MAP, while transiently decreasing heart rate and increasing and decreasing breathing rate. These results may indicate independent mechanisms by which H2S influences MAP and heart and breathing rates. The effect of Na2S in decreasing MAP was less pronounced in the presence of captopril (2 μmol/l), which may indicate that the renin-angiotensin system is partially involved in the Na2S effect. Captopril decreased H2S-induced NO release from S-nitrosoglutathione, which may be related to some biological activities of H2S. These results contribute to the understanding of the effects of H2S on the cardiovascular system., M. Drobná, A. Misak, T. Holland, F. Kristek, M. Grman, L. Tomasova, A. Berenyiova, S. Cacanyiova, K. Ondrias., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1606. Čára osudu

Creator:
Wenxing, Wang and Pělucha, Radek
Format:
print, bez média, and svazek
Type:
article, povídky, model:article, and TEXT
Subject:
Sociologie kultury. Kulturní život, 20.-21. století, tchaj-wanští spisovatelé, tchaj-wanská próza, Taiwan authors, Taiwan prose literature, 1, and 316.7
Language:
Czech
Description:
Wang Wenxing ; z čínštiny přeložil Radek Pělucha., Přeloženo z čínštiny, and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1608. Carbohydrate-binding specificities and physico-chemical properties of lectins in various tissue of phlebotominae sandflies

Creator:
Palánová, Lucie and Volf, Petr
Format:
print
Type:
model:internalpart and TEXT
Subject:
lectin, carbohydrates, sandfly, Phlebotomus, Lutzomyia, haemolymph, ovaries, midgut, and Leishmania
Language:
English
Description:
Physico-chemical properties and carbohydrate-binding specificity of hemagglutination activity (HA) were compared in tissue lysates and haemolymph of unfed and bloodied females of five sandfly species. Sandfly gut lectins were found to be heat-labile, sensitive to dithiotreitol treatment, freezing/thawing procedures and were affected by divalent cations. The pH optimum of HA ranged between 7.0-7.5. Specificity of gut HA of all species studied was directed towards aminosugars and some glycoconjugates, mainly lipopolysaccharide from Escherichia coli K-235, heparin and fetuin. Gut HA of Phlebotomus papatasi (Scopoli, 1786) was strongly inhibited by lipophosphoglycan (LPG) from Leishmania major promastigotes. In females, that took blood, the HA was higher but the carbohydrate-binding specificity remained the same; this suggests that the same lectin molecule was present, at different levels, both in unfed and fed flies. High HA was found in ovaries of fed females of Lutzomyia longipalpis (Lutz et Nieva, 1912), P. papatasi and P. duhoscqi Neveu-Lemaire, 1906. In P. papatasi and P. duboscqi the HA was present also in the haemolymph and head lysates of both fed and unfed females. Carbohydrate-binding specificity of HA present in these tissues was similar with the gut lectin.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1609. Carbohydrate-modified magnetic nanoparticles for radical scavenging

Creator:
Moskvin, M. and Daniel Horák
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, glukóza, kyselina askorbová, glucose, ascorbic acid, magnetic nanoparticles, silica, radical, scavenging, 14, and 612
Language:
English
Description:
Maghemite (γ-Fe2O3) nanoparticles, 12 nm in size, were prepared by co-precipitation of Fe(II) and Fe(III) chlorides with ammonium hydroxide and oxidation with hydrogen peroxide. To achieve stability and biocompatibility, obtained particles were coated with silica, to which glucose and ascorbic acid were bound by different mechanisms. The composite particles were thoroughly characterized by transmission electron microscopy, dynamic light scattering, elemental analysis, and FT-Raman and fluorescence spectroscopy to determine composition, morphology, size and its distribution, ζ-potential, and scavenging of peroxyl and hydroxyl radicals. As the particles showed promising antioxidative properties, they may have a possible application as a stable magnetically controlled scavenger of reactive oxygen species., M. Moskvin, D. Horák., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1610. Carbonic anhydrase - a universal enzyme of the carbon-based life

Creator:
Kupriyanova, E., Pronina, N., and Los, D.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
aktivní místo, metabolismus uhlíku, konvergentní evoluce, rozložení, funkční role, inhibitory, aktivátory, koncentrace anorganického uhlíku, active site, carbon metabolism, convergent evolution, distribution, functional role, inhibitors, activators, 2, and 581
Language:
Multiple languages
Description:
Carbonic anhydrase (CA) is a metalloenzyme that performs interconversion between CO2 and the bicarbonate ion (HCO3-). CAs appear among all taxonomic groups of three domains of life. Wide spreading of CAs in nature is explained by the fact that carbon, which is the major constituent of the enzyme’s substrates, is a key element of life on the Earth. Despite the diversity of CAs, they all carry out the same reaction of CO2/HCO3- interconversion. Thus, CA obviously represents a universal enzyme of the carbon-based life. Within the classification of CAs, here we proposed the existence of an extensive family of CA-related proteins (γCA-RPs) - the inactive forms of γ-CAs, which are widespread among the Archaea, Bacteria, and, to a lesser extent, in Eukarya. This review focuses on the history of CAs discovery and integrates the most recent data on their classification, catalytic mechanisms, and physiological roles at various organisms., E. Kupriyanova, N. Pronina, D. Los., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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