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Low-thickness La0.66Sr0.34MnO3/BiFeO3 (BFO) thin film samples deposited on SrTiO3 were imaged by high resolution x-ray microscopy at different temperatures. The ultra-thin thickness of the top layer allows to image both the ferromagnetic domain structure of LSMO and the multiferroic domain structure of the buried BFO layer, opening a path to a direct observation of coupling at the interface on a microscopic level. By comparing the domain size and structure of the BFO and LSMO, we observed that, in contrast to LSMO single layers, LSMO/BFO multilayers show a strong temperature dependence of the ferromagnetic domain structure of the LSMO. Particularly, at 40 K, a similar domain size for BFO and LSMO is observed. This indicates a persistence of exchange coupling on the microscopic scale at a temperature, where the exchange bias as determined by magnetometer measurements is vanishing. [ABSTRACT FROM AUTHOR]

Background Successful antiviral treatment of decompensated hepatitis B with HBV polymerase inhibitors is associated with improvement of liver function. To what extent liver function also improves in cirrhotic patients with chronic hepatitis C receiving novel interferon-free (IFN-free) therapies is unknown. Aim To study liver function in cirrhotic HCV patients receiving IFN-free therapies. Methods We here studied 80 consecutive patients with advanced HCV associated liver cirrhosis including 34 patients (43%) with Child B/C cirrhosis and 42 patients (53%) with platelet counts of <90.000/μL receiving different combinations of direct acting antivirals without interferon [sofosbuvir/ribavirin ( n = 56), sofosbuvir/simeprevir ± ribavirin ( n = 15) and sofosbuvir/daclatasvir ± ribavirin ( n = 9)]. The majority of patients was infected with HCV genotype 1 ( n = 50); HCV genotypes 2, 3 and 4 were present in 4, 24 and 2 patients, respectively. Results Liver function parameters including albumin, bilirubin, cholinesterase and prothrombin time all improved in the majority of patients during antiviral therapy irrespectively of the underlying HCV genotype, however, with different kinetics. MELD scores improved until post-treatment week 12 in 44% of the patients but worsened in 15%. A sustained virological response was achieved in 63% of the patients. HCV RNA relapse led to moderate ALT increases in 15/23 patients but was not associated with hepatic decompensations. Conclusion This real-world single centre study showed that interferon-free treatment of hepatitis C patients with advanced liver cirrhosis restores liver function, and may thereby reduce the need for liver transplantations. [ABSTRACT FROM AUTHOR]

1 Small and isolated populations of species are susceptible to loss of genetic diversity, owing to random genetic drift and inbreeding. This loss of diversity may reduce the evolutionary potential to adapt to changing environments, and may cause immediate loss of fitness (cf. inbreeding depression). Together with other population size-dependent stochastic processes, this may lead to increased probabilities of population extinction. 2 This set of processes and theories forms the core of conservation genetics and has developed into the conservation genetics paradigm. Many empirical studies have concentrated on the relationship between population size and genetic diversity, and in many cases evidence was found that small populations of plants do indeed have lower levels of genetic diversity and increased homozygosity. Although less empirical attention has been given to the relationship between low genetic diversity, fitness and, in particular, evolutionary potential, the paradigm is now widely accepted. 3 Here we present five areas of the paradigm which could be refined, i.e. the ‘rough’ edges of the conservation genetics paradigm. 4 Treating population size and isolation not as interchangeable parameters but as separate parameters affecting population genetics in different ways could allow more accurate predictions of the effects of landscape fragmentation on the genetic diversity and viability of populations. 5 There is evidence that inbreeding depression may be a genotype-specific phenomenon, rather than a population parameter. This sheds new light on the link between population inbreeding depression and the expected increased probability of extinction. 6 Modern eco-genomics offers the opportunity to study the population genetics of functional genes, to the extent that the role of selection can be distinguished from the effects of drift, and allowing improved insights into the effects of loss of genetic diversity on evolutionary potential. 7 Incorporating multispecies considerations may result in the generally accepted notion that small populations are at peril being called into question. For instance, small populations may be less capable of sustaining parasites or herbivores. 8 Comparative studies of endangered, common and invasive species may be a valuable approach to developing conservation biology from a phenomenological case study discipline into one investigating the general principles of what sustains biodiversity. 9 The issues discussed set an agenda for further research within conservation genetics and may lead to a further refinement of our understanding and prediction of the genetic effects of habitat fragmentation. They also underline the need to integrate ecological and genetic approaches to the conservation of biodiversity, rather than regarding them as opposites. [ABSTRACT FROM AUTHOR]

Using microsatellites, we investigated population structure and gene flow of the short-lived, wind-dispersed plant species Hypochaeris radicata in a fragmented agricultural landscape where more than 99% of the nutrient-poor grasslands have disappeared over the last century. We sampled populations in the few remaining high density populations in conservation areas, as well as individuals that occurred, with lower densities, in linear landscape elements, at two spatial scales. In a re-inventory of the landscape, after 3 years, both extinctions and colonizations of populations were observed. Contrary to expectations, no differences in genetic diversity between high and low density populations were observed. Both types of populations had relatively high levels of diversity. Overall genetic differentiation (θ) was 0.04 and significantly different from zero ( P<0.01). A significant isolation-by-distance pattern was found when all populations were simultaneously analysed ( r = 0.24, P = 0.013). Isolation by distance was (marginally) significant at the small scale ( r = 0.32, P = 0.06), whereas nonsignificant at the large spatial scale ( r = –0.05, P = 0.66). A maximization-of-explained-variance procedure resulted in a threshold distance of 3.5 km above which populations were effectively genetically isolated. An additional partial exclusion Bayesian-based assignment test showed that overall 32.3% of the individuals were assigned to their population of origin, 48% were assigned to another population in the area and 19.7% were not assigned. Together, these results suggest high levels of gene flow. Seed dispersal contributes to the observed gene flow up to several hundred metres, which is higher than previously modelled using aerodynamic models on seed dispersal of H. radicata. We discuss the consequences of these results for an evaluation of the probability of persistence of this species in the fragmented landscape. [ABSTRACT FROM AUTHOR]

Background: Fluvastatin is an inhibitor of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, effectively lowering serum cholesterol concentrations. A high-performance liquid chromatography (HPLC) assay was developed that determined the pharmacokinetics of fluvastatin in healthy individuals after administration of 40 and 80 mg fluvastatin.Methods: The method was linear for serum concentrations between 10 ng/mL and 5,000 ng/mL, showing good coefficients of variations and sample stability. After administration of 40 mg fluvastatin, the mean values of the area under the serum concentration vs time curve (AUC), the maximum serum drug concentration (C(max)), the time to reach C(max) (t(max)), and the serum elimination half-life time were 528.5 +/-358.8 ng/mL x h, 149.6 +/-56.0 ng/mL, 60.0 +/-30.0 minutes, and 108.0 +/-67.9 minutes, respectively. The corresponding values for a dose of 80 mg fluvastatin were 1417.7 +/-879.2 ng/mL x h, 1024.7 +/-1085.1 ng/mL, 60.0 +/-21.2 minutes, and 106.0 +/-73.6 minutes, respectively. Doubling of the dose from 40 mg to 80 mg caused an overproportional increase of AUC and C(max).Results and Conclusion: Results suggest that the measurement of fluvastatin serum concentrations by means of HPLC provides reliable data within the broad range of physiological serum concentrations. The pharmacokinetic data after administration of high doses (80 mg) showed an overproportional increase of AUC and C(max), suggesting a saturation of the hepatic first-pass effect. Thus, in patients treated with additional substances interfering with fluvastatin metabolism, fluvastatin serum concentrations should be analyzed. [ABSTRACT FROM AUTHOR]

We developed five highly polymorphic dinucleotide microsatellite loci for the grassland species Hypochaeris radicata (Asteraceae). Polymorphism of these markers was examined in six populations in the Netherlands. All loci were polymorphic in all populations. The number of alleles per locus varied between 18 and 43. Expected heterozygosity was between 0.86 and 0.91. Cross-species amplification was tested in six Hypochaeris species and was successful for three different loci in four species. These microsatellites are a useful tool in population genetic, dispersal and metapopulation studies or in testing levels of inbreeding. [ABSTRACT FROM AUTHOR]