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3032. Bioluminiscence hub - odvěký a stále záhadný fenomén
- Creator:
- Michal Sochor and Egertová, Zuzana
- Format:
- print, bez média, and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, bioluminiscence, houby, mykologie, bioluminescence, mushrooms, mycology, Fungi, Mycena chlorophos, Filoboletus manipularis, 2, and 57/59
- Language:
- Czech
- Description:
- Ačkoli bylo světélkování u hub doloženo již ve starověku, intenzivnějšího vědeckého studia se tomuto jevu dostává teprve v posledních letech. Článek shrnuje naše dosavadní poznání bioluminiscence u hub z hlediska evolučního, ekologického i fyziologického. Jeho součástí jsou i fotografie dvou tropických druhů se světélkujícími plodnicemi - Mycena chlorophos a Filoboletus manipularis., Bioluminescence in fungi was first observed in the Archaic period or earlier, but it has only recently been studied scientifically. This paper sums up our knowledge on this phenomenon from evolutionary, ecological, and physiological points of view. Included are photos of two tropical species with luminescent fruiting bodies - Mycena chlorophos and Filoboletus manipularis., and Michal Sochor, Zuzana Egertová.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3033. Biomarkers of cardiometabolic risk in obese/overweight children: effect of lifestyle inetrvention
- Creator:
- Michal Vrablík, Milada Dobiášová, Lukáš Zlatohlávek, Zuzana Urbanová, and Richard Češka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, obézní děti, obezita, overweight children, obesity, AIP [Log(TG/HDL-C)], ApoB/apoAI ratio, HOMA-IR (insulin resistance), cardiometabolic risk markers, intensive lifestyle intervention, obese children, 14, and 612
- Language:
- English
- Description:
- Obesity is a strong cardiometabolic (CM) risk factor in children. We tested potential CM risk in obese/overweight children and the effect of an intensive lifestyle intervention using newer CM markers: atherogenic index of plasma AIP [Log(TG/HDL-C)], apoB/apoAI ratio and a marker of insulin resistance HOMA-IR. The participants (194 girls, 115 boys, average age 13) were enrolled in an intensive, one-month, inpatient weight reduction program. The program consisted of individualised dietary changes and the exercise program comprised aerobic and resistance training. Anthropometrical and biochemical parameters in plasma and CM risk biomarkers - (AIP, apoB/apoAI ratio and HOMA-IR) were examined before and after the intervention. AIP and HOMA-IR significantly correlated with BMI while apoB/apoAI ratio did not. Only AIP and HOMA-IR showed systematic increases according to the level of obesity by BMI quartiles. Lifestyle intervention significantly improved anthropometrical and biochemical values and the biomarkers too. The response of lipid parameters to the intervention was considerably higher in boys than in girls. The children were stratified into three risk categories according to AIP, where 13.8 % of boys and 5.3 % of girls fell into high risk category. The monitored biomarkers may complement each other in the prognosis of CM risk. AIP was strongly related to obesity and to lipid and glycid metabolism, while the relationship of the apoB/apoAI ratio to obesity and glycid metabolism was not significant. The obese children benefited from the intensive lifestyle intervention which improved the anthropometrical and biochemical parameters and CM risk biomarkers., M. Vrablík, M. Dobiášová, L. Zlatohlávek, Z. Urbanová, R. Češka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3034. Biomarkers of cellular apoptosis and necrosis in donor myocardium are not predictive of primary graft dysfunction
- Creator:
- Ondrej Szárszoi, Josef Bešík, Michal Smetana, Jan Malý, Urban, M., Jana Malušková, Alena Lodererová, Lenka Hošková, Tucanova, Z., Jan Pirk, and Ivan Netuka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, transplantace srdce, apoptóza, nekróza, heart transplantation, apoptosis, necrosis, primary graft dysfunction, 14, and 612
- Language:
- English
- Description:
- Primary graft dysfunction (PGD) is a life-threatening complication among heart transplant recipients and a major cause of early mortality. Although the pathogenesis of PGD is still unclear, ischemia/reperfusion injury has been identified as a predominant factor. Both necrosis and apoptosis contribute to the loss of cardiomyocytes during ischemia/reperfusion injury, and this loss of cells can ultimately lead to PGD. The aim of our prospective study was to find out whether cell death, necrosis and apoptosis markers present in the donor myocardium can predict PGD. The prospective study involved 64 consecutive patients who underwent orthotopic heart transplantation at our institute between September 2010 and January 2013. High-sensitive cardiac troponin T (hs-cTnT) as a marker of minor myocardial necrosis was detected from arterial blood samples before the donor’s pericardium was opened. Apoptosis (caspase-3, active + pro-caspase-3, bcl-2, TUNEL) was assessed from bioptic samples taken from the right ventricle prior graft harvesting. In our study, 14 % of transplant recipients developed PGD classified according to the standardized definition proposed by the ISHLT Working Group. We did not find differences between the groups in regard to hs-cTnT serum levels. The mean hs-cTnT value for the PGD group was 57.4±22.9 ng/l, compared to 68.4±10.8 ng/l in the group without PGD. The presence and severity of apoptosis in grafted hearts did not differ between grafts without PGD and hearts that subsequently developed PGD. In conclusion, our findings did not demonstrate any association between measured myocardial cell death, necrosis or apoptosis markers in donor myocardium and PGD in allograft recipients. More detailed investigations of cell death signaling pathways in transplanted hearts are required., O. Szarszoi, J. Besik, M. Smetana, J. Maly, M. Urban, J. Maluskova, A. Lodererova, L. Hoskova, Z. Tucanova, J. Pirk, I. Netuka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3035. Biomass partition, leaf gas exchange and water relations of alfalfa and milkvetch seedlings in response to soil drying
- Creator:
- Xu, B.-C., Deng, X.-P., Zhang, S.-Q., and Shan, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, hydraulic root signal, root shoot ratio, nonhydraulic root signal, and water stress
- Language:
- Multiple languages
- Description:
- This study compared physiological and growth responses to water stress of two legume species during the seedling stage. Potted alfalfa (Medicago sativa L. cv. Algonquin) and milkvetch (Astragalus adsurgens Pall. cv. Pengyang earlymaturing vetch) seedlings were grown under well-watered [soil water content (SWC) maintained at 14.92% daily] or water-stressed conditions (drying) for 15 days. Net photosynthetic rate (PN), transpiration rate (E) and stomatal conductance (gs) of both species decreased parabolically. When SWC decreased to 7.2% and 10.3%, gs values for alfalfa and milkvetch were significantly different from those of the respective well-watered plants (p<0.05). When SWC decreased to 6.6% for alfalfa and 6.8% for milkvetch, leaf water potentials (ψL) were significantly different from those of the well-watered plants (p<0.05). Thus the difference between the SWC thresholds for a nonhydraulic root signal (nHRS) and a hydraulic root signal (HRS) were 0.6% and 3.5% for alfalfa and milkvetch, respectively. Milkvetch had a lower gs than alfalfa for a given SWC (p<0.05). Although alfalfa seedlings had a higher dry mass (DM) and root:shoot ratio (R/S) than milkvetch in both treatments (p<0.05), we concluded that milkvetch seedlings had greater drought tolerance than alfalfa. and B.-C. Xu ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3036. Biomass partitioning and gas exchange in Dalbergia sissoo seedlings under water stress
- Creator:
- Singh, B. and Singh, G.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- arid areas, leaf water potential, net photosynthetic rate, soil water availability, stomatal conductance, transpiration rate, and water use efficiency
- Language:
- Multiple languages
- Description:
- Biomass, leaf water potential (Ψl), net photosynthetic rate (PN), transpiration rate (E), stomatal conductance (gs), leaf to air temperature difference (Tdiff), and instantaneous water use efficiency (WUE) were measured in the seedlings of Dalbergia sissoo Roxb. grown under irrigation of 20 (W1), 14 (W2), 10 (W3), and 8 (W4) mm. Treatments were maintained by re-irrigation when water content of the soil reached 7.4% in W1, 5.6% in W2, 4.3% in W3, and 3.2% in W4. Seedlings in a control (W5) were left without irrigation after maintaining the soil field capacity (10.7%). Seedlings of W1 had highest biomass that was one tenth in W5. Biomass allocation was highest in leaf in W2 and in root in W4 and W5 treatments. Difference between predawn leaf water potential (ΨPd) and midday (Ψmid) increased with soil water stress and with vapour pressure deficit (VPD) in April and May slowing down the recovery in plant leaf water status after transpiration loss. PN, E, and gs declined and Tdiff increased from W1 to W5. Their values were highly significant in April and May for the severely stressed seedlings of W4 and W5. PN increased from 08:00 to 10:00 and E increased until 13:00 within the day for most of the seedlings whereas gs decreased throughout the day from 08:00 to 17:00. PN and E were highest in March but their values were low in January, February, April, and May. Large variations in physiological variables to air temperature, photosynthetically active radiation, and vapour pressure deficit (VPD) indicated greater sensitivity of the species to environmental factors. WUE increased from W1 to W2 but decreased drastically at high water stress particularly during hot summer showing a kind of adaptation in D. sissoo to water stress. However, low biomass and reduced physiological functions at <50% of soil field capacity suggest that this species does not produce significant biomass at severe soil water stress or drought of a prolonged period. and B. Singh, G. Singh.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3037. Biomechanical analysis of the dummy responses in case of child pedestrian/cyclist collision with passenger car
- Creator:
- Schejbalová, Zuazana, Mičunek , Tomáš, and Schmidl , Drahomír
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Child cyclist, child pedestrian, passenger car, dynamic test, collision configuration, biomechanical load, accidents and losses minimization, and prediction diagnostics
- Language:
- English
- Description:
- The safety of pedestrians and cyclists in traffic is justified especially in terms of prevention. This paper deals with the biomechanical analysis of load exerted on the child pedestrian and cyclist. In the case of cyclists, the impact configurations were chosen with respect to the statistical outputs (sudden enter the road or the case of non-giving way; the car front vs. the left side of the cyclists). Two tests were performed in the same configuration and nominal collision speed, the first one with a bicycle helmet and the second one without the helmet. The initial position of pedestrian was chosen with respect to the dummy degrees of freedom. Using the accelerometers in the head, chest, pelvis and knee of the dummy acceleration fields were detected, which are the child pedestrian and cyclist exposed during the primary and secondary collision. In addition, prediction diagnostics method implementation was discussed such as one possible solution of vulnerable road users harm reduction. In conclusion, the results are interpreted by values of biomechanical load and severity of potential injuries including kinematic and dynamic comparison.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3038. Biomechanical characterization of cartilages by a novel approach of blunt impact testing
- Creator:
- Ferdinand Varga, Držík, M., Milan Handl, Chlpík, J., Petr Kos, Elena Filová, Michala Rampichová, Alois Nečas, Tomáš Trč, and Evžen Amler
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, tkáňové inženýrství, tissue engineering, cartilage biomechanics, impact testing, poroelastic material, impact energy dissipation, 14, and 612
- Language:
- English
- Description:
- The present article introduces a novel method of characterizing the macromechanical cartilage properties based on dynamic testing. The proposed approach of instrumented impact testing shows the possibility of more detailed investigation of the acting dynamic forces and corresponding deformations within the wide range of strain rates and loads, including the unloading part of stress-strain curves and hysteresis loops. The presented results of the unconfined compression testing of both the native joint cartilage tissues and potential substitute materials outlined the opportunity to measure the dissipation energy and thus to identify the initial mechanical deterioration symptoms and to introduce a better definition of material damage. Based on the analysis of measured specimen deformation, the intact and pathologically changed cartilage tissue can be distinguished and the differences revealed., F. Varga, M. Držík, M. Handl, J. Chlpík, P. Kos, E. Filová, M. Rampichová, A. Nečas, T. Trč, E. Amler., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3039. Biomechanical model of pregnant female for impact purposes
- Creator:
- Jansová, Magdalena and Hynčík, Luděk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- human model, pregnant female, validation, and impact
- Language:
- English
- Description:
- Biomechanics has widely expanded in the last decades. The last development of computers provides new possibilities in this field. Problems can be solved faster and can be more extensive. One of these problems is the biomechanical model of human body. Its realisaton is practically impossible without using computers, because it is necessary to solve systems of thousands of equations. There are several software packages that enable human body modeling. One of them is the PAM environment [15] developed by the ESI Group International. This computational system is based on the Finite Element Method and is one of the mostly used systems for crash test simulations. Various human body models for various purposes are developed. Pregnant female model serve to optimize safety systems in cars to be more friendly to pregnant abdomen. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3040. Biomechanical study of disk implants. Part I
- Creator:
- Borák, Libor, Marcián, Petr, Florian, Zdeněk, and Bartáková, Sonia
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- dental implant, osseointegration, FEM, bone, and density
- Language:
- English
- Description:
- The presented work is focused on the biomechanical study of the dental disk implant. The first part of the study deals with the strain analysis of the affected bone tissue and the dental implant loaded in the coronoapical direction by force 190 N. The study includes three types of implant anchorge, four degrees (stages) of osseointegration and nine degrees describing the quality of the cancellous bone. Two types of the disk implant were researched: single-disk and double-disk implant. Biomechanical study of the implant was focused on a stress-strain analysis of the affected bone rissue. The highest influence on the stresses in the bone tissue was primarily an implant anchorage. By the application of correlation relationships between Young modulus and the apparent density of the bone tissue - which is measurable in patients - we achieved the variable presented in this study. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public