• MeSH
• biokompatibilní materiály účinky záření   MeSH
• ethylenoxid MeSH
• kolagen MeSH
• polyestery MeSH
• sterilizace metody   MeSH
• testování materiálů metody   MeSH
• Publikační typ
• práce podpořená grantem MeSH

The objective of the project is to create and elaborate the general theory which would explain, on the base of deep anaysis particularly physical characteristics, the present differences between long-term success of biological substitutes under condidtions of low flow under 100ml/min and complete failure of arteficial vascular prostheses under the same conditions. On the base of results of these analyses and tests to find out the crucial key characteristics which optimization would prepare the field for the construction of vascular prostheses comparable to biological substitutes under the same conditions On the base of almost half century experience with the research of vascular substitutes we have certain hypotheses, but they can be prooved only on the base of laboratory and experimental results The positive outcome of the project would be the substantial contribution to cardiovascular surgery

Předmětem řešení je hlubokou analýzou především fysikálních charakteristik náhrad biologických a základních typů náhrad umělých vypracovat theorii, která by vysvětlovala stávající řádové rozdíly mezi jejich úspěšností za podmínek nízkého průtoku pod 100ml/min. Na základě takto vytvořené theorie pak optimalizovat a konkrétizovat zásadní charakeristiky, které by umožnily konstrukci umělé cévní náhrady, která by se svou úspěšností blížila náhradám biologikcým. Na základě vlastních dlouholetých zkušeností v této oblasti máme své odůvodněné představy o optimálním směru výzkumu, jehož kladný výsledek vy zásadně rozšířil možnosti kardiovaskulární rekonstrukční chirurgie

• MeSH
• autologní štěp MeSH
• autologní transplantace MeSH
• cévní protézy MeSH
• cévy - implantace protéz MeSH
• cévy fyziologie   MeSH
• fyziologie MeSH
• rychlost toku krve MeSH
• výkony cévní chirurgie MeSH
• výzkum MeSH
• zákroky plastické chirurgie MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• angiologie
• cévní chirurgie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu IGA MZ ČR

• Publikační typ
• abstrakt z konference MeSH

• Publikační typ
• abstrakt z konference MeSH

This study introduces a new quantity, the combined arteriosclerotic index (CAI), which is defined as the ratio between the diameter and the longitudinal prestrain of an artery. The longitudinal prestrain has been adopted as the ratio between the in situ length and the excised length of the abdominal aorta, and is a measure of arterial elasticity. During ageing, arteriosclerosis is manifested by the loss of pretension and by enlargement of the diameter of the artery. CAI combines these two effects. A sample of 61 female and 194 male autopsy measurements of human abdominal aortas shows that CAI correlates significantly with chronological age (R = 0.916/0.921; female/male). The sample had the following parameters: age 53 ± 19/48 ± 16 years; diameter of the abdominal aorta 12.4 ± 2.2/13.4 ± 2.1 mm; and longitudinal prestrain 1.13 ± 0.10/1.15 ± 0.10 (mean ± sample standard deviation; female/male). The resulting CAI was 11.2 ± 2.7/11.9 ± 2.6 mm. The classical linear regression model was employed for age estimation by CAI. The model gave a residual standard deviation of 7.6/6.3 years and a 95% prediction interval range of  ± 15.4/12.5 years (female/male). A two-sample t-test confirmed that there are significant differences between the female and male population during ageing, reflected by CAI, unlike longitudinal prestrain. It was concluded that CAI is a suitable predictor of age at time of death and is easily obtainable in the autopsy room.

• MeSH
• aorta abdominalis patologie   MeSH
• arterioskleróza patologie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• lineární modely MeSH
• mladý dospělý MeSH
• mrtvola MeSH
• pitva metody   MeSH
• pružnost MeSH
• stárnutí patologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

It is a well-known fact that the length of an artery in situ and the length of an excised artery differs. Retraction of blood vessels is usually observed. This pre-tension plays crucial role in arterial biomechanics. It augments an artery wall load-bearing capacity. This paper presents the longitudinal pre-strain of the human aorta as an index of human age. The length of abdominal aortas was measured during autopsies before and after segment resection. The longitudinal pre-strain was calculated in 130 donors; 100 male and 30 female bodies. The pre-strain was defined as the ratio between in situ length and the length after the excision. The mean pre-strain was found to be 1.18±0.10 for male and 1.14±0.10 for female sample (mean±standard deviation). The age in the male group was 41.6±15.9 years; and 47.7±17.7 years in the female group. Statistical analysis revealed the correlation coefficient between age and pre-strain r=-0.821 and r=-0.839 in male and female group, respectively. The analysis also confirmed close correlation between aortic circumference and age; and between circumference and pre-strain. Linear and power law regression equations were employed and prediction intervals were computed. The power law estimates the age more accurately than linear one model. Nevertheless, especially for small values of the pre-strain (aged individuals) the linear model can be advantageous.

• MeSH
• aorta abdominalis patologie   MeSH
• aterosklerotický plát patologie   MeSH
• ateroskleróza patologie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mechanický stres MeSH
• regresní analýza MeSH
• soudní patologie MeSH
• stárnutí fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The longitudinal prestrain of arteries facilitates their physiological function. Remodeling, adaptation and aging result in an age-dependent magnitude of the pretension. Although the phenomenon is known, detailed statistics, especially for human arteries, are lacking. This study was designed to propose the regression model capable of estimating the prestrain of the human abdominal aorta. The length of the abdominal aorta before, l, and after excision from the body, L, the diameter, heart weight, thickness of left ventricle and degree of atherosclerosis were collected in autopsies of 156 male cadavers of known age. Longitudinal prestrain was quantified by means of the stretch ratio λ=l/L. Statistical analysis revealed significant dependence between age, prestrain, diameter and atherosclerosis, which were best fitted to the power law equation. Longitudinal prestretch reduced with age significantly; λmean=1.30±0.07 for age<30 (n=29), whereas λmean=1.06±0.03 for age>59 (n=31) with p-value<0.0001. Raw data gave linear correlation coefficients as follows: λ-age (R=-0.842); l-age (R=0.023); L-age (R=0.476); (l-L)-age (R=-0.811). It was concluded that longitudinal prestrain decreases nonlinearly with age and both age and diameter are suitable predictors of the prestrain. Data suggests that unloaded length elongates with age in contrast to the elastic retraction.

• MeSH
• aorta abdominalis patologie   patofyziologie   MeSH
• ateroskleróza patofyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mechanický stres MeSH
• regresní analýza MeSH
• stárnutí fyziologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH