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866. 3D echocardiography - a useful method for cardiovascular risk assessment in end-stage renal disease patients

Creator:
Kovářová, Magdaléna, Žilinská, Zuzana, Páleš, Ján, Kužmová, Zuzana, Gažová, Andrea, Smaha, Juraj, Kužma, Martin, Jackuliak, Peter, Štvrtinová, Viera, Kyselovič, Ján, and Payer, Juraj
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
fyziologie člověka, lékařství, human physiology, medicine, End-stage chronic kidney disease, Hemodialysis, Kidney transplantation, Ankle-brachial index, Echocardiography, 14, and 612
Language:
English
Description:
a1_Patients with chronic kidney disease (CKD) have an increased risk of premature mortality, mainly due to cardiovascular causes. The association between hemodialysis and accelerated atherosclerosis has long been described. The ankle-brachial index (ABI) is a surrogate marker of atherosclerosis and recent studies indicate its utility as a predictor of future cardiovascular disease and all-cause mortality. The clinical implications of ABI cut-points are not well defined in patients with CKD. Echocardiography is the most widely used imaging method for cardiac evaluation. Structural and functional myocardial abnormalities are common in patients with CKD due to pressure and volume overload as well as non-hemodynamic factors associated with CKD. Our study aimed to identify markers of subclinical cardiovascular risk assessed using ABI and 2D and 3D echocardiographic parameters evaluating left ventricular (LV) structure and function in patients with end-stage renal disease (ESRD) (patients undergoing dialysis), patients after kidney transplantation and non-ESRD patients (control). In ESRD, particularly in hemodialysis patients, changes in cardiac structure, rather than function, seems to be more pronounced. 3D echocardiography appears to be more sensitive than 2D echocardiography in the assessment of myocardial structure and function in CKD patients. Particularly 3D derived end-diastolic volume and 3D derived LV mass indexed for body surface appears to deteriorate in dialyzed and transplanted patients. In 2D echocardiography, myocardial mass represented by left ventricular mass/body surface area index (LVMI) appears to be a more sensitive marker of cardiac structural changes, compared to relative wall thickness (RWT), left ventricle and diastolic diameter index (LVEDDI) and left atrial volume index (LAVI)., a2_We observed a generally favorable impact of kidney transplantation on cardiac structure and function; however, the differences were non-significant. The improvement seems to be more pronounced in cardiac function parameters, peak early diastolic velocity/average peak early diastolic velocity of mitral valve annulus (E/e´), 3D left ventricle ejection fraction (LV EF) and global longitudinal strain (GLS). We conclude that ABI is not an appropriate screening test to determine the cardiovascular risk in patients with ESRD., Magdaléna Kovářová, Zuzana Žilinská, Ján Páleš, Zuzana Kužmová, Andrea Gažová, Juraj Smaha, Martin Kužma, Peter Jackuliak, Viera Štvrtinová, Ján Kyselovič, Juraj Payer., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

867. 3D how much can we trust some moment tensors or an attempt of seismic moment error estimation

Creator:
Kolář, Petr
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, seizmicita, seismicity, seismic moment tensor inversion, error estimation, seismic moment decomposition, 7, and 551
Language:
English
Description:
During routine processing of selected events of an active KTB experiment it has appeared doubts concerning data reliability and consequently the reliability of results based on them. In the paper 3 events are studied in detail, full seismic moment tensors, as well as their errors, are determined (by non-linear inversion of P/SH waves ratios). It is shown that for the processed low constrained data moment tensor (MT) can be determined, however the relative error is of order of first tens of percent; the results also considerably depend on the way of data picking, used medium model, way of Cost function construction, etc. Any subsequent geophysical interpretation therefore should takes into account this uncertainty. MTs are finally decomposed into DC and non-DC parts, MTs errors are also transformed., Petr Kolář., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

868. 3D microscopic imaging and evaluation of tubular tissue architecture

Creator:
Jiří Janáček, Čapek, M., Michálek, J., Petr Karen, and Lucie Kubínová
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, mozek, brain, confocal microscopy, capillaries, skeletal muscle, image analysis, 14, and 612
Language:
English
Description:
3D microscopy and image analysis provide reliable measurements of length, branching, density, tortuosity and orientation of tubular structures in biological samples. We present a survey of methods for analysis of large samples by measurement of local differences in geometrical characteristics. The methods are demonstrated on the structure of the capillary bed in a rat brain., J. Janáček ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

869. 3D monitoring of active fault structures in the Krupnik-Kresna seismic zone, SW Bulgaria

Creator:
Dobrev, Nikolai
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, seizmické oblasti, seismic regions, Bulharsko, Bulgaria, 3D monitoring, active faults, co-seismic displacements, Krupnik-Kresna seismic zone, SW Bulgaria, 7, and 551
Language:
English
Description:
The present paper concerns long-term 3D monitoring of active fault structures in the Krupnik-Kresna seismic zone, SW Bulgaria with the use of extensometers TM71. The purpose is to establish the real rates of fault movements in the most seismically active area in Bulgaria. Three points were installed (B6 on Krupnik Fault, and K5 and K12 on Struma Fault), which indicate a recent activity. The fault movements are characteristic with “calm” periods, linear slips, accelerations and sudden displacements. Different regimes of dynamics have been established corresponding to different periods. The greatest dynamics is found at monitoring point B6 along Krupnik Fault: for the whole period of observation the trends are calculated as left lateral slip with 1.88 mm/a and a thrusting with 1.59 mm/a with high correlation coefficients. Co-seismic displacements from local and distant earthquakes were recorded. The significant impact was from M=7.4, 17 August, 1999, Izmit Earthquake, Turkey, showing a shortening of 8.34 mm, a right-lateral slip of 5.09 mm and a thrusting of 0.96 mm. After that, for a short period of time the regime of movement on fault was changed. Movements on the Struma system reveal lower rates. Both points show left-lateral movements, 0.28 mm/a at K5 and 0.09 mm/a at K12, and thrusting with 0.11 mm/a at K5 and 0.72 mm/a at K12., Nikolai Dobrev., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

870. 3D monitoring of active faults and slope movements in three Bulgarian sites included in cost 625 project

Creator:
Dobrev, Nikolai and Avramova-Tacheva, Elka
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, tenzometrie, svahy, extensometry, slopes (physical geography), fault, slope movement, 3D monitoring, 7, and 551
Language:
English
Description:
The present paper shows the results of 3D monitoring with the use of extensomet ers TM71 performed in Bulgaria in the framework of COST Action 625. This research was performed in selected areas: Simitli graben that is the most seismoactive area in Bulgaria; Madara plat eau - rock scarp with historical monument affe cted by rock toppling; East Rhodopes area - a possibly active fault zone and a large landslide. The most impressive results were established at Simitli graben area with the rate of 2.73 mm/year sinistral movement of Krupnik Fault. Local earthquakes located at NE part of the graben usually influence the movements along this fault. An acceleration of the left latera l movements during calm periods has been established, and respectively, the movements stop (or going in opposite direction) during seismic activity. At Madara site, the results from the 15 years monitoring show subsidence of rock s lices by 0.9 mm per year and si milar rate movement of the slices to South direction. Influence from Izmit earthquake, Vrancea earthquakes and local ones have been established. The monitoring of the fault at General Geshe vo Village, East Rhodopean area started in 2003. The first results show mainly gravitational movements - subsidence of NE block 1.5 mm/year., Nikolai Dobrev and Elka Avramova-Tacheva., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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