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3132. Biochemical and biophysical aspects of collagen nanostructure in the extracellular matrix
- Creator:
- Koláčná, L., Bakešová, J., Ferdinand Varga, Eva Košťáková, Ladislav Plánka, Alois Nečas, David Lukáš, Evžen Amler, and Václav Pelouch
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kolagen, nanovlákna, popraviště, collagen, nanofibers, scaffolds, extracellular matrix, biomechanical properties, 14, and 612
- Language:
- English
- Description:
- ECM is composed of different collagenous and non-collagenous proteins. Collagen nanofibers play a dominant role in maintaining the biological and structural integrity of various tissues and organs, including bone, skin, tendon, blood vessels, and cartilage. Artificial collagen nanofibers are increasingly significant in numerous tissue engineering applications and seem to be ideal scaffolds for cell growth and proliferation. The modern tissue engineering task is to develop three-dimensional scaffolds of appropriate biological and biomechanical properties, at the same time mimicking the natural extracellular matrix and promoting tissue regeneration. Furthermore, it should be biodegradable, bioresorbable and non-inflammatory, should provide sufficient nutrient supply and have appropriate viscoelasticity and strength. Attributed to collagen features mentioned above, collagen fibers represent an obvious appropriate material for tissue engineering scaffolds. The aim of this minireview is, besides encapsulation of the basic biochemical and biophysical properties of collagen, to summarize the most promising modern methods and technologies for production of collagen nanofibers and scaffolds for artificial tissue development., L. Koláčná, J. Bakešová, F. Varga, E. Košťáková, L. Plánka, A. Nečas, D. Lukáš, E. Amler, V. Pelouch., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3133. Biochemical and morphological changes in isolated rabbit hearts after prolonged hypothermic ischaemia: Comparison of two cardioplegic solutions
- Creator:
- Poltronieri, R., Cevese, a., Bregu, R., Motta, A., Zancanaro, C., and Bernocchi, P.
- Type:
- article, model:article, and TEXT
- Subject:
- hypothermic cardioplegia, high energy phosphates, creatine kinase, lactate, and ultrastructural preservation
- Language:
- English
- Description:
- This work evaluates the myocardial protective potential of potassium cardioplegia on ischaemically arrested and reperfused hearts by two cardioplegic solutions: the University of Wisconsin solution (UW) and the standard crystalloid solution of St. Thomas’ Hospital (ST). Evaluation of myocardial preservation was based on creatine kinase and lactate releases and on high-energy phosphate preservation of isolated rabbit hearts after 4 hours’ hypothermic ischaemia. A morphometric ultrastructural evaluation of mitochondria in cardiomyocytes was also performed. The hearts of 24 rabbits were normothermally perfused with oxygenated Krebs-Henseleit solution for 30 min (Langendorff preparation), and the baseline contractile performance and biochemical parameters were evaluated. The hearts were then arrested and stored in the cardioplegic solutions (12 UW and 12 ST) at 4 °C for 4 hours. The hearts were then rewarmed and reperfused with oxygenated Krebs-Henseleit solution for further 30 min. At the end of reperfusion, creatine phosphate and high energy phosphates were higher with UW (p<0.05); creatine kinase release during reperfusion was significantly lower with UW both at 15 min (p<0.01) and at 30 min (p<0.05). Lactate release during the first 15 min of reperfusion was about doubled (p<0.05) with respect to controls in both groups; at 30 min this increase had almost vanished ( + 8 %) with UW but not with ST ( + 30 %). Ultrastructural morphometry did not show any significant difference at the level of mitochondria between the two treatments. The results indicate, for UW, an improved myocardial preservation associated with relative retention of high-energy phosphates and higher recovery of mechanical function, accelerated metabolic recovery and reduced stress of cell membranes.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3134. Biochemical Changes of Enzymatic Defense System after Phenanthrene Exposure in Olive Flounder, Paralichthys olivaceus
- Creator:
- Jee, J.-H and Kang, J.-C
- Type:
- article, model:article, and TEXT
- Subject:
- Antioxidant enzymes, Detoxification, Oliver flounder, Phase II enzyme, and Phenanthrene
- Language:
- English
- Description:
- The objective of this study was to investigate the early biological response in the olive flounder exposed to sub-lethal concentrations of waterborne phenanthrene (0.5, 1 or 2 μM). The fish were exposed for 4 weeks and we analyzed their enzymatic defense system, antioxidant and phase II enzyme activities, to evaluate the chronic exposure toxicity of phenanthrene. Waterborne phenanthrene affected antioxidant enzymes and glutathione-mediated detoxification as an enzyme defense system. Hepatic, gill and kidney glutathione reductase as well as glutathione S-transferase, and catalase activities were markedly elevated after two or four weeks of exposure. These enzyme activities of the olive flounder, Paralichthys olivaceus, seem to be a convenient approach for monitoring pollution in coastal areas against polycyclic aromatic hydrocarbon pollution including phenanthrene.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3135. Biochemical characteristics of cardiac collagen and its role in ventricular remodelling following infarction
- Creator:
- Pelouch, V. and Jirmář, R.
- Type:
- article, model:article, and TEXT
- Subject:
- collagenous proteins, contractile proteins, cardiac muscle, myocardial infarction, and remodelling of ventricular musculature
- Language:
- English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3136. Biochemical effects of low level exposure to soman vapour
- Creator:
- Bajgar, Jiří
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3137. Biochemical markers of endothelial dysfunction in patients with endocrine and essential hypertension
- Creator:
- Petrák, O., Widimský Jr., J., Zelinka, T., Kvasnik´čka, J. , Štrauch, B., Holaj, R. , Štulc, T., Kvasnička, T. , Bílková, J. , and Škrha, J.
- Type:
- article, model:article, and TEXT
- Subject:
- Essential hypertension, Pheochromocytoma, Primary hyperaldoteronism, Endothelial dysfunction, and Adhesive molecules
- Language:
- English
- Description:
- The aim of our study was to evaluate potential differences in the concentration of biochemical markers of endothelial dysfunction between essential hypertension, endocrine hypertension (pheochromocytoma, primary hyperaldosteronism) and control healthy group and to assess a potential relationship between these markers of endothelial dysfunction and vasopressor substances overproduced in endocrine hypertension. We have investigated 21 patients with moderate essential hypertension, 29 patients with primary hyperaldosteronism, 24 subjects with pheochromocytoma and 26 healthy volunteers. Following parameters of endothelial dysfunction were measured, von Willebrand factor (vWf), plasminogen activator (t-PA) and E-selectin (E-sel). Clinical blood pressure was measured according to the European Society of Hypertension recommendations. We found significantly higher levels of the von Willebrand factor in patients with essential hypertension in comparison with a control group (114±20 IU/dl vs 90±47 IU/dl; P=0.04) and patients with primary hyperaldosteronism (114±20 IU/dl vs 99±11 IU/dl; P=0.01). Patients with endocrine hypertension revealed increased levels of vWF compared to the control group, but these differences did not reach statistical significance. Levels of t-PA were increased in patients with pheochromocytoma in comparison with the control group (4.6±1.9 ng/ml vs 3.4±0.9 ng/ml; P=0.01) and with primary hyperaldosteronism (4.6±1.9 ng/ml vs 3.4±1.1 ng/ml; P<0.01). In case of E-selectin we found lower levels in patients with pheochromocytoma in comparison with other groups, but they differed significantly only with primary hyperaldosteronism (40.2±15.0 ng/ml vs 51.3±23.0 ng/ml; P=0.05). Our study did not reveal any convincing evidence of differences in the levels of biochemical markers of endothelial dysfunction between essential and endocrine hypertension. No correlation between the biochemical markers of endothelial dysfunction and vasopressor substances activated in endocrine hypertension was found.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3138. Biochemical network of drug-induced enzyme production: parameter estimation based on the periodic dosing response measurement
- Creator:
- Lynnyk, Volodymyr, Papáček, Štěpán, and Rehák, Branislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- parameter estimation, dynamical system, systems pharmacology, biochemical network, input-output regulation, and fast Fourier transform
- Language:
- English
- Description:
- The well-known bottleneck of systems pharmacology, i. e., systems biology applied to pharmacology, refers to the model parameters determination from experimentally measured datasets. This paper represents the development of our earlier studies devoted to inverse (ill-posed) problems of model parameters identification. The key feature of this research is the introduction of control (or periodic forcing by an input signal being a drug intake) of the nonlinear model of drug-induced enzyme production in the form of a system of ordinary differential equations. First, we tested the model features under periodic dosing, and subsequently, we provided an innovative method for a parameter estimation based on the periodic dosing response measurement. A numerical example approved the satisfactory behavior of the proposed algorithm.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3139. Biochemistry of Transmembrane Signaling Mediated by Trimeric G Proteins
- Creator:
- Svoboda, P., Teisinger, J., Novotný, J., Bouřová, L., Drmota, T., Hejnová, L., Moravcová, Z., Lisý, V., Rudajev, V., Stöhr, J. , Vokurková, A., Švandová, I., and Durchánková, D.
- Type:
- article, model:article, and TEXT
- Subject:
- GPCR, Trimeric G proteins, Caveolae, Desensitization, and Na, K-ATPase
- Language:
- English
- Description:
- Many extracellular signals are at the cell surface received by specific receptors, which upon activation transduce information to the appropriate cellular effector molecules via trimeric G proteins. The G protein-mediated cascades ultimately lead to the highly refined regulation of systems such as sensory perception, cell growth, and hormonal regulation. Transmembrane signaling may be seriously deranged in various pathophysiological conditions. Over the last two decades the major experimental effort of our group has been devoted to better understanding the molecular mechanisms underlying transmembrane signaling regulated by G proteins and to the closely related process of desensitization of hormone response. This review provides general information about the basic principles of G protein-regulated transmembrane signaling as well as about our contribution to the current progress in the field.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3140. Biocompatible hydrogels in spinal cord injury repair
- Creator:
- Aleš Hejčl, Petr Lesný, Martin Přádný, Jiří Michálek, Pavla Jendelová, Jan Štulík, and Eva Syková
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, neurofyziologie, poranění míchy, hydrogely, tkáňové inženýrství, kmenové buňky, regenerační medicína, neurophysiology, spinal cord injuries, hydrogels, tissue engineering, stem cells, regenerative medicine, 14, and 612
- Language:
- English
- Description:
- Spinal cord injury results in a permanent neurological deficit due to tissue damage. Such a lesion is a barrier for “communication” between the brain and peripheral tissues, effectors as well as receptors. One of the primary goal s of tissue engineering is to bridge the spinal cord injury and re-establish the damaged connections. Hydrogels are biocompatible implants used in spinal cord injury repair. They can create a permissive environment and bridge the lesion cavities by providing a scaffold for the regeneration of neurons and their axons, glia and other tissue elements. The advantage of using artificial materials is the possibility to modify their physical and chemical properties in order to develop the best implant suitable for spinal cord injury repair. As a result, several types of hydrogels have been tested in experimental studies so far. We review our work that has been done during the last 5 years with various types of hydrogels and their applications in experimental spinal cord injury repair., A. Hejčl, P. Lesný, M. Přádný, J. Michálek, P. Jendelová, J. Štulík, E. Syková., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public