• MeSH
• hemodynamika fyziologie   MeSH
• hypofýza chirurgie   MeSH
• krysa rodu rattus MeSH
• ledviny fyziologie   MeSH
• lékové roztoky chemie   terapeutické užití   MeSH
• osmotický tlak MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH

Marine-to-terrestrial transition represents one of the most fundamental shifts in microbial life. Understanding the distribution and drivers of soil microbial communities across coastal ecosystems is critical given the roles of microbes in soil biogeochemistry and their multifaceted influence on landscape succession. Here, we studied the fungal community dynamics in a well-established salt marsh chronosequence that spans over a century of ecosystem development. We focussed on providing high-resolution assessments of community composition, diversity and ecophysiological shifts that yielded patterns of ecological succession through soil formation. Notably, despite containing 10- to 100-fold lower fungal internal transcribed spacer abundances, early-successional sites revealed fungal richnesses comparable to those of more mature soils. These newly formed sites also exhibited significant temporal variations in β-diversity that may be attributed to the highly dynamic nature of the system imposed by the tidal regime. The fungal community compositions and ecophysiological assignments changed substantially along the successional gradient, revealing a clear signature of ecological replacement and gradually transforming the environment from a marine into a terrestrial system. Moreover, distance-based linear modelling revealed soil physical structure and organic matter to be the best predictors of the shifts in fungal β-diversity along the chronosequence. Taken together, our study lays the basis for a better understanding of the spatiotemporally determined fungal community dynamics in salt marshes and highlights their ecophysiological traits and adaptation in an evolving ecosystem.

• MeSH
• biodiverzita MeSH
• ekologie MeSH
• ekosystém MeSH
• houby klasifikace   genetika   fyziologie   MeSH
• mokřady * MeSH
• půda MeSH
• půdní mikrobiologie * MeSH
• salinita MeSH
• životní prostředí MeSH
• Publikační typ
• časopisecké články MeSH

The aim of the present study was to characterize intraventricular pressure gradients (IVPGs) in an animal model of chronic heart failure. New Zealand rabbits were treated with doxorubicin (heart failure group, n=5) or saline (control group, n=5) and instrumented with pressure catheters placed in the apex and outflow-tract of left ventricle (LV) and with sonomicrometer crystals placed in the apex and base of the LV free wall. In heart failure animals, ventricular filling was delayed and slower when compared with control animals. Moreover, the physiological nonuniformity observed between apical and basal segments in normal hearts was abolished in failing hearts. Simultaneously, physiological IVPGs observed during normal ventricular filling were entirely lost in heart failure animals. During ventricular emptying physiological nonuniformity between apical and basal segments observed in control animals was also abolished in heart failure animals. In failing hearts minimal length occurred later and almost at same time both in apical and in basal myocardial segments. Simultaneously, the characteristic IVPG pattern observed in healthy hearts during systole, which promotes ventricular emptying, was not observed in failing hearts. The present study showed that diastolic IVPGs, a marker of normal ventricular filling, and systolic IVPGs, a marker of normal ventricular emptying, are abolished in heart failure.

• MeSH
• časové faktory MeSH
• chronická nemoc MeSH
• diastola MeSH
• doxorubicin MeSH
• dysfunkce levé srdeční komory chemicky indukované   patofyziologie   ultrasonografie   MeSH
• funkce levé komory srdeční * MeSH
• komorový tlak (srdce) * MeSH
• králíci MeSH
• modely nemocí na zvířatech MeSH
• srdeční selhání chemicky indukované   patofyziologie   ultrasonografie   MeSH
• systola MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Regioisomers and enantiomers of triacylglycerols (TAGs) containing any combination of stearidonic (18:4n-3) and octadecapentaenoic (18:5n-3) acids were prepared by organic synthesis. Gradient polar organic liquid chromatography/high resolution atmospheric pressure chemical ionization-tandem mass spectrometry (NARP-LC/HRMS(2)-APCI) and chiral liquid chromatography were used for the separation and identification of molecular species of these TAGs. Further, NARP-LC and chiral LC were used to separate natural mixtures of TAGs obtained from the haptophyte alga Coccolithophora sp. cultivated in a salinity range from 7.5 to 60‰. The ratio of regioisomers and enantiomers was found to change with increasing salinity of the culture medium. This can be explained by variable activity of acyltransferases in cells exposed to salt stress.

• MeSH
• atmosférický tlak MeSH
• nenasycené mastné kyseliny chemie   izolace a purifikace   MeSH
• omega-3 mastné kyseliny chemie   izolace a purifikace   MeSH
• stereoizomerie MeSH
• tandemová hmotnostní spektrometrie MeSH
• triglyceridy chemie   izolace a purifikace   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH

Previously published multidisciplinary studies in the Miramichi and Bouctouche rivers (New Brunswick, Canada) noted significant changes in fish health parameters, including elevated tissue levels of organic contaminants and a wide range of physiological disturbances, in mummichog Fundulus heteroclitus (L.) from a site on the Miramichi River that received bleached kraft pulpmill and municipal effluent. The present study reports differences in the abundance of individual parasite species, as well as parasite infracommunity and component community composition, in mummichog from both rivers. These differences were evaluated in relation to host (size, condition, immune function, tissue organochlorine contaminant levels) and environmental (faecal coliform counts, salinity, temperature) data derived from the previously published studies. Overall, 18 parasite species were identified, the most common of which were Ascocotyle sp. larv., Ornithodiplostomum sp. larv., Posthodiplostomum sp. larv., and Proteocephalus filicollis (Rudolphi, 1802). There were broad differences in parasite community structure and composition between rivers and within rivers, the most prominent pattern being a pronounced difference between sites in the upper and lower estuary of each river that was likely driven by salinity. Mean infracommunity richness was also positively related to faecal coliforms (considered here as a surrogate measure of eutrophication via municipal sewage), and both were highest at the most polluted site. We noted no other significant relationships. Thus our data suggest that the parasite communities in these two estuaries were primarily structured by large upstream/downstream ecological gradients in salinity, and secondarily by eutrophication due to pollution by municipal and industrial effluents. Overall, our results highlight the value of coordinated multidisciplinary studies for understanding the factors that shape parasite abundance and community structure.

• MeSH
• demografie MeSH
• ekosystém MeSH
• Fundulidae MeSH
• lidské činnosti MeSH
• nemoci ryb epidemiologie   parazitologie   MeSH
• parazitární nemoci u zvířat epidemiologie   parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Geografické názvy
• New Brunswick MeSH

Publikace se zaměřuje na evoluční vývoj buňky, cytologii a související genetické a membránové procesy. Určeno široké veřejnosti.; Kniha se věnuje zkoumání buňky z různých úhlů pohledu.Postupně seznamuje se základními vlastnostmi živé hmoty, životními formami, evolucí a vznikem života, vlastnostmi a původem molekul, tvořících stavební prvky buněčného těla, fyzikálně-chemickými principy podstatnými pro fungování buněčného mechanismu, významem a funkcí biologických membrán, metabolismem, transportem, signalizací a získáváním energie pro životní procesy, aby v závěru vyvrcholil charakteristikou eukaryotických buněk, které jsou podstatou všech mnohobuněčných organismů, včetně člověka. Významnou část knihy tvoří kapitoly věnované světu nukleových kyselin, zejména RNA a DNA, uchovávajících genetickou informaci ve formě genetického kódu, a syntéze proteinů, součástí buněk veškerých živých organismů. Kniha je doplněna množstvím názorných schémat a obrázků.

• MeSH
• biologická evoluce MeSH
• biologie buňky MeSH
• genetika MeSH
• membrány MeSH
• molekulární biologie * MeSH
• Publikační typ
• monografie MeSH
• populární práce MeSH

• Konspekt
• Biochemie. Molekulární biologie. Biofyzika
• NLK Obory
• biologie
• molekulární biologie, molekulární medicína

The causes of biodiversity patterns are controversial and elusive due to complex environmental variation, covarying changes in communities, and lack of baseline and null theories to differentiate straightforward causes from more complex mechanisms. To address these limitations, we developed general diversity theory integrating metabolic principles with niche-based community assembly. We evaluated this theory by investigating patterns in the diversity and distribution of soil bacteria taxa across four orders of magnitude variation in spatial scale on an Antarctic mountainside in low complexity, highly oligotrophic soils. Our theory predicts that lower temperatures should reduce taxon niche widths along environmental gradients due to decreasing growth rates, and the changing niche widths should lead to contrasting α- and β-diversity patterns. In accord with the predictions, α-diversity, niche widths and occupancies decreased while β-diversity increased with increasing elevation and decreasing temperature. The theory also successfully predicts a hump-shaped relationship between α-diversity and pH and a negative relationship between α-diversity and salinity. Thus, a few simple principles explained systematic microbial diversity variation along multiple gradients. Such general theory can be used to disentangle baseline effects from more complex effects of temperature and other variables on biodiversity patterns in a variety of ecosystems and organisms.

• MeSH
• Bacteria metabolismus   MeSH
• ekosystém MeSH
• mikrobiota * MeSH
• půdní mikrobiologie * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Geografické názvy
• Antarktida MeSH

Standardization of fertilization protocols is crucial for improving reproductive techniques for externally fertilizing fish in captive breeding. Therefore, the objectives of this study were to determine the effects of preincubation of eggs and activation medium on the percentage of eyed embryos for ide (Leuciscus idus). Pooled eggs from five females were preincubated in three different activating media for 0, 30, 60, 90, and 120 seconds and then fertilized by pooled sperm from five males. At the eyed-egg stage, the percentage of viable embryos was later calculated. Results showed that preincubation time was significant for the freshwater activation medium (P < 0.001), such that the percentage of eyed embryos declined across the preincubation time gradient. Additionally, there was an effect on the percentage of eyed embryos when eggs were incubated with Woynarovich solution (P < 0.001), such that a decline was detected at 90 seconds, whereas no effect was detected for the saline water medium. Activating medium had a significant effect on the percentage of eyed embryos for each preincubation time (P < 0.05). More precisely, freshwater produced the lowest percentage of eyed embryos at all preincubation times (ranged from 1.9% at 120 seconds to 43.6% at 0 seconds), whereas saline water and Woynarovich solution produced the highest percentage of eyed embryos at 0 seconds and 30 seconds before incubation. Woynarovich solution produced the highest percentage of eyed embryos at 60 seconds (65.26%), whereas saline water produced the highest percentage at 90 seconds (68.37%). No difference was detected between saline water and Woynarovich solution at 120 seconds. Examination of sperm traits showed no impact of activating medium on computer assisted sperm analysis parameters. Together, these results suggest that saline water or Woynarovich solution improve fertilization rate in ide during IVF; thus, these media are useful for standardizing fertilization protocols and controlled reproduction for this species.

• MeSH
• chov MeSH
• Cyprinidae * embryologie   fyziologie   MeSH
• embryo nesavčí MeSH
• fertilizace in vitro metody   veterinární   MeSH
• fertilizace účinky léků   fyziologie   MeSH
• kultivace embrya * metody   veterinární   MeSH
• kultivační média farmakologie   MeSH
• oči účinky léků   embryologie   MeSH
• sexuální chování zvířat fyziologie   MeSH
• spermie účinky léků   fyziologie   MeSH
• uchování spermatu veterinární   MeSH
• zvířata MeSH
• zygota účinky léků   MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

PURPOSE: The quality and precision of post-mortem MRI microscopy may vary depending on the embedding medium used. To investigate this, our study evaluated the impact of 5 widely used media on: (1) image quality, (2) contrast of high spatial resolution gradient-echo (T1 and T2* -weighted) MR images, (3) effective transverse relaxation rate (R2* ), and (4) quantitative susceptibility measurements (QSM) of post-mortem brain specimens. METHODS: Five formaldehyde-fixed brain slices were scanned using 7.0T MRI in: (1) formaldehyde solution (formalin), (2) phosphate-buffered saline (PBS), (3) deuterium oxide (D2 O), (4) perfluoropolyether (Galden), and (5) agarose gel. SNR and contrast-to-noise ratii (SNR/CNR) were calculated for cortex/white matter (WM) and basal ganglia/WM regions. In addition, median R2* and QSM values were extracted from caudate nucleus, putamen, globus pallidus, WM, and cortical regions. RESULTS: PBS, Galden, and agarose returned higher SNR/CNR compared to formalin and D2 O. Formalin fixation, and its use as embedding medium for scanning, increased tissue R2* . Imaging with agarose, D2 O, and Galden returned lower R2* values than PBS (and formalin). No major QSM offsets were observed, although spatial variance was increased (with respect to R2* behaviors) for formalin and agarose. CONCLUSIONS: Embedding media affect gradient-echo image quality, R2* , and QSM in differing ways. In this study, PBS embedding was identified as the most stable experimental setup, although by a small margin. Agarose and Galden were preferred to formalin or D2 O embedding. Formalin significantly increased R2* causing noisier data and increased QSM variance.

• MeSH
• ethery MeSH
• fluorokarbony MeSH
• formaldehyd MeSH
• fosfáty MeSH
• kontrastní látky MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie přístrojové vybavení   metody   MeSH
• mapování mozku metody   MeSH
• mozek diagnostické zobrazování   patologie   MeSH
• odběr biologického vzorku MeSH
• oxid deuteria MeSH
• pitva přístrojové vybavení   metody   MeSH
• počítačové zpracování obrazu MeSH
• poměr signál - šum MeSH
• sefarosa chemie   MeSH
• senioři MeSH
• zalévání tkání přístrojové vybavení   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: The association between maternal age and risk of Down syndrome has been repeatedly shown in various populations. However, the effect of paternal age and education of parents has not been frequently studied. Comparative studies on Down syndrome are also rare. This study evaluates the epidemiological characteristics of Down syndrome in two culturally and socially contrasting population settings, in California and the Czech Republic. METHODS: The observed live birth prevalence of Down syndrome was studied among all newborns in the California counties monitored by California Birth Defects Monitoring Program from 1996 to 1997, and in the whole Czech Republic from 1994 to 1998. Logistic regression was used to analyze the data. RESULTS: A total of 516,745 (California) and 475,834 (the Czech Republic) infants were included in the analysis. Among them, 593 and 251, respectively, had Down syndrome. The mean maternal age of children with Down syndrome was 32.1 years in California and 26.9 years in the Czech Republic. Children born to older mothers were at greater risk of Down syndrome in both populations. The association with paternal age was mostly explained by adjusting for maternal age, but remained significant in the Czech Republic. The association between maternal education and Down syndrome was much stronger in California than in the Czech Republic but parental age influences higher occurrence of Down syndrome both in California and in the Czech Republic. CONCLUSION: The educational gradient in California might reflect selective impact of prenatal diagnosis, elective termination, and acceptance of prenatal diagnostic measures in Californian population.

• MeSH
• dospělí MeSH
• Downův syndrom diagnóza   epidemiologie   etnologie   MeSH
• financování organizované MeSH
• hodnocení rizik MeSH
• indukovaný potrat MeSH
• lidé středního věku MeSH
• lidé MeSH
• logistické modely MeSH
• novorozenec MeSH
• prenatální diagnóza MeSH
• prevalence MeSH
• průzkumy a dotazníky MeSH
• registrace MeSH
• rodiče výchova   MeSH
• stupeň vzdělání MeSH
• těhotenství MeSH
• věk matky MeSH
• věk otce MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• srovnávací studie MeSH
• Geografické názvy
• Česká republika MeSH
• Kalifornie MeSH