Search

Start Over Subject biochemie

22. Colon submucosal microdialysis: a novel in vivo approach in barrier function assessment - a pilot study in rats

Creator:
Norbert Cibiček, Helena Živná, Zdeněk Zadák, Jiří Kulíř, Čermáková, E., and Vladimír Palička
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Biochemie. Molekulární biologie. Biofyzika, biochemie, tlusté střevo, potkan, biochemistry, large intestine, Rattus norvegicus, mikrodialýza, microdialysis, colon barrier function, Cr-EDTA permeability, 2, and 577
Language:
English
Description:
During shock, prognosis of a patient depends largely on intestinal barrier function. The potency of gut epithelium to represent an obstacle to toxins is determined by the blood supply. All established methods of mucosal function determination necessitate the functional involvement of bloodstream. Microdialysis allows monitoring of extracellular substances in the gut submucosa, but its potential use for gut barrier integrity assessment is unknown. Twelve rats underwent perfusion of the descending colon either with 20 % ethanol or control medium (vehicle). Both media contained equal amounts of a radioactive tracer substance (51Cr-EDTA). Mucosal permeability for 51Cr-EDTA was assessed by microdialysate to luminal perfusate activity ratios. Sampling was performed using the colon submucosal microdialysis technique. The group subjected to ethanol treatment had profound macro- and microscopical alterations in perfused colonic segment associated with a significant increase in tracer permeability during ethanol exposure (2.354±0.298 % for ethanol as opposed to 0.209±0.102 % for control group, p<0.01), which remained elevated for 60 min after cessation of ethanol administration (3.352±0.188 % for ethanol compared to 0.140± 0.0838 % for the control group, p<0.001). Submucosal microdialysis with radioactive tracer substance can be considered a feasible and advantageous alternative of gut barrier function estimation. Parallel monitoring of local tissue chemistry with this method remains a challenge in the future., N. Cibiček, H. Živná, Z. Zadák, J. Kulíř, E. Čermáková, V. Palička., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

23. Correlation of ultrastructural changes of endothelial cells and astrocytes occuring during blood brain barrier damage after traumatic brain injury with biochemical markers of blood brain barrier leakage and inflammatory response

Creator:
David Vajtr, Oldřich Benada, Jiří Kukačka, Richard Průša, Ladislav Houšťava, Pavel Toupalík, and René Kizek
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, biochemie, hematoencefalická bariéra, metaloproteiny, biochemistry, blood-brain barrier, metalloproteins, S-100B protein, interleukin-6, 14, and 612
Language:
English
Description:
a1_Focal cerebral contusion can be dynamic and expansive. It has been proved that subsequent expansive contusion is caused by brain parenchyma damage, especially BBB damage. We investigated a group of patients with traumatic brain injury. The patients (n=18) were divided in to group I (n=7) of patients submitted to neurosurgery due to expansive contusion, and group II (n=11) of patients without surgery. Serum concentrations of NSE and S-100B protein were measured by electrochemiluminescence immunoassay, interleukin-6 (IL-6) was measured by chemiluminescent sequential immunometric assay and matrix metalloproteinases (MMP-9, MMP-2) were measured by immunoassays. Cortical biopsy specimens of brain were investigated by electron microscopy in patients with trauma brain injury submitted to neurosurgery. Biochemical investigation from first day up to third day after traumatic brain injury proved increased values of IL-6 (302.2±119.9 vs. 59.6±11.9 ng/l, p<0.02) and S-100B protein (3.064±1.064 vs. 0.649±0.182 μ g/l, p<0.05) in patients with expansive lesion compared to patients without expansive contusion. Significantly higher levels of MMP-9 (150.4±28.46 vs. 74.11±13.16 ng/l, p<0.05) and of MMP-2 (814.5±126.3 vs. 523.1±25.28 ng/l, p<0.05) were found during first 3 days after admission in group I compared to group II. MMP-9 has also elevated in group II from lower values after admission (74.11±13.16 ng/l) up to high levels on the 10th day of hospitalization (225.1±49.35 ng/l )., a2_Ultrastructural investigation of endothelial cells and surrounded tissue revealed perivascular hemorrhage, increased pinocytic activity of endothelial cells, and cytotoxic edema of astroglial cells. Multivesical bodies were disclosed inside the endothelial cells. Higher levels of serum protein S-100B and IL-6 correlated with ultrastructural changes of endothelial cells, and with inflammatory response following TBI, respectively., D. Vajtr ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

24. Cyklus Organická chemie

Creator:
Zdeněk Drahota and Ústav makromolekulární chemie (Československá akademie věd)
Publisher:
ČSAV. Ústav organické chemie a biochemie
Format:
print and v, 205 s.
Type:
model:monograph and TEXT
Subject:
Biochemie. Molekulární biologie. Biofyzika, biochemie, 577.1, (048.8), 2, and 577
Language:
Czech
Description:
Sv. 9, Vybrané kapitoly z biochemie, Z. Drahota ... [et al.]., and Na titulní str. uveden rok vydání 1982
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

25. Dějiny Ústavu organické chemie a biochemie AV ČR /

Creator:
Franc, Martin,
Publisher:
MÚA AV ČR pro ÚOCHB AV ČR,
Type:
monografie
Subject:
Organická chemie, Akademie věd ČR, Ústav organické chemie a biochemie, instituce vědecké, chemie organická, biochemie, české a československé vědecké instituce a společnosti, vysoké školy, Československo 1945-1992, české země od r. 1993 do současnosti, and chemické vědy, alchymie
Language:
Czech
Description:
Obsahuje bibliografii, bibliografické odkazy a rejstřík
Rights:
unknown

28. Differences in activities of antioxidant superoxide dismutase, glutathione peroxidase and prooxidant xanthine oxidoreductase/xanthine oxidase in the normal corneal epithelium of various mammals

Creator:
Kovačeva, J., Jan Pláteník, Martin Vejražka, Stanislav Štípek, Taras Ardan, Čestmír Čejka, Midelfart, A., and Jitka Čejková
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Biochemie. Molekulární biologie. Biofyzika, biochemie, savci, rohovka, antioxidanty, biochemistry, mammals, cornea, antioxidants, epitel, prooxidanty, epithelium, prooxidants, 2, and 577
Language:
English
Description:
Under normal conditions, antioxidants at the corneal surface are balanced with the production of reactive oxygen species without any toxic effects. Danger from oxidative stress appears when natural antioxidants are overwhelmed leading to antioxidant/prooxidant imbalance. The aim of the present study was to examine the activities of enzymes contributing to the antioxidant/prooxidant balance in normal corneal epithelium of various mammals. The enzyme activities of antioxidant superoxide dismutase and glutathione peroxidase, as well as prooxidant xanthine oxidoreductase/xanthine oxidase were examined using biochemical methods. Results show that superoxide dismutase activity is high in rabbits and guinea pigs, whereas in pigs the activity is low and in cows it is nearly absent. In contrast, glutathione peroxidase activity is high in cows, pigs and rabbits, whereas in guinea pigs the activity is low. As far as prooxidant enzymes are concerned, elevated xanthine oxidoreductase/xanthine oxidase activities were found in rabbits, lower activities in guinea pigs, very low activity in cows and no activity in pigs. In conclusion, the above results demonstrate inter-species variations in activities of enzymes participating in antioxidant/prooxidant balance in the corneal epithelium. It is suggested that the levels of antioxidant and prooxidant enzymes studied in the corneal epithelium might be associated with the diurnal or nocturnal activity of animals. UV rays decompose hydrogen peroxide to damaging hydroxyl radicals and perhaps for this reason large animals with diurnal activity (cow, pig) require more effective peroxide removal (high glutathione peroxidase activity) together with the suppression of peroxide production (low superoxide dismutase activity, low xanthine oxidoreductase activity)., J. Kovačeva, J. Pláteník, M. Vejražka, S. Štípek, T. Ardan, Č. Čejka, A. Midelfart, J. Čejková., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

29. Differential effects of statins and alendronate on cholinesterases in serum and brain of rats

Creator:
Cibičková, Ľ., Vladimír Palička, Norbert Cibiček, Čermáková, E., Stanislav Mičuda, Ladislava Bartošová, and Daniel Jun
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Biochemie. Molekulární biologie. Biofyzika, biochemie, cholesterol, Alzheimerova choroba, biochemistry, Alzheimer's disease, simvastin, atorvastin, alendronate, acetylcholinesterase, 2, and 577
Language:
English
Description:
Acetylcholinesterase (AChE) inhibitors represent standard treatment of Alzheimer´s disease. Cholesterol plays an important role in Alzheimer´s disease development. Because cholesterol synthesis may be inhibited by statins or bisphosphonates, we hypothesized that these drugs might possibly have an influence on cholinesterases. Moreover, we also evaluated if the cholesterol-lowering agents that cross the blood-brain barrier (e.g. simvastatin) should be more effective than those which do not (e.g. atorvastatin). Four groups of rats were orally administered simvastatin, atorvastatin, alendronate or vehicle for seven days. Thereafter, blood samples were taken and the basal ganglia, septum, frontal cortex, and hippocampus were isolated from brains for measurement of acetylcholinesterase activity. In the blood, activities of neither acetyl- nor butyrylcholinesterase were influenced by any of the applied drugs. In the brain, no significant changes in AChE activity were observed after administration of atorvastatin. Both simvastatin and alendronate significantly suppressed the activity of AChE in the frontal cortex. In conclusion, our results confirmed the hypothesis that cholesterol-modifying drugs modulate AChE activity and it is more reasonable to use a blood-brain barrier penetrating drug., Ľ. Cibičková, V. Palička, N. Cibiček, E. Čermáková, S. Mičuda, L. Bartošová, D. Jun., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

30. Distribution and interrelationship of ubiquitin proteasome pathway component activities and ubiquitin pools in various porcine tissues

Creator:
Patel, M. B. and Majetschak, Matthias
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, biochemie, homeostáza, biochemistry, homeostasis, proteazom, ubikvitin, proteasome, ubiquitin, ubiquitin protein ligase system, ubiquitin protein conjugates, tissue distribution, ubiquitin homeostasis, 14, and 612
Language:
English
Description:
The ubiquitin-proteasome pathway fulfills major biological functions, but its physiologic tissue distribution and the interrelationship between pathway component activities and ubiquitin pools are unknown. Therefore, we analyzed free and conjugated ubiquitin, ubiquitin-protein ligation rates (UbPL) and chymotryptic- and tryptic-like proteasome peptidase activities in porcine skeletal muscle, heart, lung, liver, spleen and kidney (n=5 each). There were considerable differences between tissues (p<0.05 for all parameters). Lung and spleen showed high levels of free and conjugated ubiquitin and high UbPL. Proteasome activities were highest in kidney and heart. There were linear relationships between tryptic-like and chymotryptic-like proteasome peptidase activities (r2 = 0.624, p<0.001) and between free and conjugated ubiquitin tissue levels (r2 = 0.623, p<0.001). Tissue levels of free and conjugated ubiquitin correlated linear with UbPL (p<0.005), but they were not correlated with proteasome peptidase activities. The results suggest that tissue ubiquitin pools are tightly regulated and indicate a constant proportion of conjugated ubiquitin. They further support the hypothesis that ubiquitin-protein ligase systems, and probably deubiquitylating enzymes, are key regulators of ubiquitin homeostasis. The detected differences are suggestive of tissue-specific roles of ubiquitin-proteasome pathway components. Besides the known importance of the ubiquitin proteasome pathway in heart, kidney and the immune system, the results suggest the lung as another organ in which ubiquitin proteasome pathway components may also significantly contribute to disease processes., M. B. Patel, M. Majetschak., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

Limit your search

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

View distribution

Current results range from 1922 to 2017

View larger »