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801.
802.
Trends in genetic diversity among European maize cultivars and their parental components during the past 50 years 总被引:3,自引:0,他引:3
Reif JC Hamrit S Heckenberger M Schipprack W Maurer HP Bohn M Melchinger AE 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(5):838-845
It has been claimed that the system that delivers the products of plant breeding reduces the diversity of cultivated varieties
leading to an increased genetic vulnerability. The main goal of our study was to monitor the temporal trends in genetic diversity
over the past five decades among maize cultivars with the largest acreage in Central Europe. Our objectives were to (1) investigate
how much of the genetic diversity present in important adapted open-pollinated varieties (OPVs) has been captured in the elite
flint germplasm pool, (2) examine changes in the genetic diversity among the most important commercial hybrids as well as
in their dent and flint parents, (3) analyze temporal changes in allele frequencies between the dent and flint parental inbreds,
and (4) investigate linkage disequilibrium (LD) trends between pairs of loci within the set of parental dent and flint lines.
We examined 30 individuals of five prominent OPVs from Central Europe, 85 maize hybrids of economic importance, and their
dent and flint parental components with 55 SSRs. LD was significant at probability level P=0.01 for 20.2% of the SSR marker pairs in the 82 dent lines and for 17.2% in the 66 flint lines. The dent and flint heterotic
groups were clearly separated already at the beginning of hybrid breeding in Central Europe. Furthermore, the genetic variation
within and among varieties decreased significantly during the five decades. The five OPVs contain numerous unique alleles
that were absent in the elite flint pool. Consequently, OPVs could present useful sources for broadening the genetic base
of elite maize breeding germplasm. 相似文献
803.
Thuridur A. Gudnadóttir Brian T. Bateman Sonia Hernádez-Díaz Miguel Angel Luque-Fernandez Unnur Valdimarsdottir Helga Zoega 《PloS one》2016,11(3)
While obesity is an indicated risk factor for hypertensive disorders of pregnancy, smoking during pregnancy has been shown to be inversely associated with the development of preeclampsia and gestational hypertension. The purpose of this study was to investigate the combined effects of high body mass index and smoking on hypertensive disorders during pregnancy. This was a case-control study based on national registers, nested within all pregnancies in Iceland 1989–2004, resulting in birth at the Landspitali University Hospital. Cases (n = 500) were matched 1:2 with women without a hypertensive diagnosis who gave birth in the same year. Body mass index (kg/m2) was based on height and weight at 10–15 weeks of pregnancy. We used logistic regression models to calculate odds ratios and corresponding 95% confidence intervals as measures of association, adjusting for potential confounders and tested for additive and multiplicative interactions of body mass index and smoking. Women’s body mass index during early pregnancy was positively associated with each hypertensive outcome. Compared with normal weight women, the multivariable adjusted odds ratio for any hypertensive disorder was 1.8 (95% confidence interval, 1.3–2.3) for overweight women and 3.1 (95% confidence interval, 2.2–4.3) for obese women. The odds ratio for any hypertensive disorder with obesity was 3.9 (95% confidence interval 1.8–8.6) among smokers and 3.0 (95% confidence interval 2.1–4.3) among non-smokers. The effect estimates for hypertensive disorders with high body mass index appeared more pronounced among smokers than non-smokers, although the observed difference was not statistically significant. Our findings may help elucidate the complicated interplay of these lifestyle-related factors with the hypertensive disorders during pregnancy. 相似文献
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Rodrigo AC Rivilla I Pérez-Martínez FC Monteagudo S Ocaña V Guerra J García-Martínez JC Merino S Sánchez-Verdú P Ceña V Rodríguez-López J 《Biomacromolecules》2011,12(4):1205-1213
A novel hybrid dendrimer (TRANSGEDEN) that combines a conjugated rigid polyphenylenevinylene (PPV) core with flexible polyamidoamine (PAMAM) branches at the surface was synthesized and characterized. The potential of this material as a nonviral gene delivery system was also examined, and it was observed that dendriplexes formed by TRANSGEDEN and small interfering ribonucleic acids (siRNAs) can be incorporated into >90% of neuronal cells without any toxicity up to a dendrimer concentration of 3 μM. TRANSGEDEN was used to deliver a specific siRNA to rat cerebellar granular neurons (CGNs) to knock down the cofilin-1 protein. Cofilin-1 removal partially protects CGNs from N-methyl D-aspartate (NMDA)-mediated neuronal death. 相似文献
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807.
Lorenzo Parri Ada Fort Anna Lo Grasso Marco Mugnaini Valerio Vignoli Clemente Capasso Sonia Del Prete Maria Novella Romanelli Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):393
In this paper, the efficiency of the carbonic anhydrase (CA) enzyme in accelerating the hydration of CO2 is evaluated using a measurement system which consists of a vessel in which a gaseous flow of mixtures of nitrogen and CO2 is bubbled into water or water solutions containing a known quantity of CA enzyme. The pH value of the solution and the CO2 concentration at the measurement system gas exhaust are continuously monitored. The measured CO2 level allows for assessing the quantity of CO2, which, subtracted from the gaseous phase, is dissolved into the liquid phase and/or hydrated to bicarbonate. The measurement procedure consists of inducing a transient and observing and modelling the different kinetics involved in the steady-state recovery with and without CA. The main contribution of this work is exploiting dynamical system theory and chemical kinetics modelling for interpreting measurement results for characterising the activity of CA enzymes. The data for model fitting are obtained from a standard bioreactor, in principle equal to standard two-phase bioreactors described in the literature, in which two different techniques can be used to move the process itself away from the steady-state, inducing transients. 相似文献
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