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51.
Worldwide glaciers are annually retreating due to global overheating and this phenomenon determines the potential lost of microbial diversity represented by psychrophilic microbial population sharing these peculiar habitats. In this context, yeast strains, all unable to grow above 20°C, consisting of 42 strains from Antarctic soil and 14 strains isolated from Alpine Glacier, were isolated and grouped together based on similar morphological and physiological characteristics. Sequences of the D1/D2 and ITS regions of the ribosomal DNA confirmed the previous analyses and demonstrated that the strains belong to unknown species. Three new species are proposed: Mrakia robertii sp. nov. (type strain CBS 8912), Mrakia blollopis sp. nov. (type strain CBS 8921) and a related anamorphic species Mrakiella niccombsii sp. nov. (type strain CBS 8917). Phylogenetic analysis of the ITS region revealed that the new proposed species were closely related to each other within the Mrakia clade in the order Cystofilobasidiales, class Tremellomycetes. The Mrakia clade now contains 8 sub-clades. Teliospores were observed in all strains except CBS 8918 and for the Mrakiella niccombsii strains.  相似文献   
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Despite being the number one fruit crop in the world, very little is known about the phylogeny and molecular biology of banana (Musa spp.). Six banana rbcS gene families encoding the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase from six different Musa spp. are presented. For a comprehensive phylogenetic study using Musa rbcS genes, a total of 57 distinct rbcS sequences was isolated from six accessions that contained different combinations of the A and B ancestral/parental genomes. As a result, five of the six members of the rbcS gene family could be affiliated with the A and/or B Musa genomes and at least three of the six gene families most likely existed before Musa A and B genomes separated. By combining sequence data with quantitative real-time PCR it was determined that the different Musa rbcS gene family members are also often multiply represented in each genome, with the highest copy numbers in the B genome. Expression of some of the rbcS genes varied in intensity and in different tissues indicating differences in regulation. To analyse and compare regulatory sequences of Musa rbcS genes, promoter and terminator regions were cloned for three Musa rbcS genes. Transient transformation assays using promoter-reporter-terminator constructs in maize, wheat, and sugarcane demonstrated that the rbcS-Ma1, rbcS-Ma3, and rbcS-Ma5 promoters could be useful for transgene expression in heterologous expression systems. Furthermore, the rbcS-Ma1 terminator resulted in a 2-fold increase of transgene expression when directly compared with the widely used Nos terminator.  相似文献   
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Koi herpesvirus (KHV) was identified as being associated with more than one mortality event affecting common carp in Canada. The first was an extensive mortality event that occurred in 2007 in the Kawartha Lakes region, Ontario, affecting Lakes Scugog and Pigeon. Fish had branchial necrosis and hepatic vasculitis with an equivocal interstitial nephritis. Several fish also had branchial columnaris. Subsequent mortality events occurred in 2008 in additional bodies of water in south-central Ontario, such as Lake Katchewanooka and outside of Ontario in Lake Manitoba, Manitoba. Koi herpesvirus was detected in fish submitted for examination from all of these lakes by polymerase chain reaction (PCR), and sequence of the PCR product revealed 100% homology to KHV strains U and I. Real-time PCR analysis of KHV-infected wild carp revealed viral loads ranging from 6.02×10(1) to 2.4×10(6) copies μg(-1) host DNA. This is the first report of KHV in Canada.  相似文献   
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Both enantiomers of petromyroxol are putative pheromones in sea lamprey (Petromyzon marinus). Here, we describe the separation and quantification of the petromyroxol enantiomers using high‐performance liquid chromatography tandem mass spectrometry. The separation was tested on a wide range of chiral columns with normal phases, and effects of the chromatographic parameters such as mobile phase and temperature on the separation were optimized. The AD‐H column showed the best separation of enantiomers with n‐hexane and ethanol as the mobile phase. The enantiomers were detected by multiple reaction monitoring with a positive atmospheric‐pressure chemical ionization on triple quadrupole mass spectrometer. Validation revealed that the method was specific, accurate, and precise. The validated method was applied to measure the amount of petromyroxol enantiomers in water conditioned with sea lamprey larvae, the source of the putative pheromone. This method will be applied in quantifying the natural scalemic petromyroxol mixture, enabling further investigations of a rare non‐racemic enantiomeric pheromone mixture in a vertebrate species.  相似文献   
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Objectives

Cognitive deficits are common in patients with chronic heart failure (CHF), but no study has investigated whether these deficits extend to social cognition. The present study provided the first empirical assessment of emotion recognition and theory of mind (ToM) in patients with CHF. In addition, it assessed whether each of these social cognitive constructs was associated with more general cognitive impairment.

Methods

A group comparison design was used, with 31 CHF patients compared to 38 demographically matched controls. The Ekman Faces test was used to assess emotion recognition, and the Mind in the Eyes test to measure ToM. Measures assessing global cognition, executive functions, and verbal memory were also administered.

Results

There were no differences between groups on emotion recognition or ToM. The CHF group’s performance was poorer on some executive measures, but memory was relatively preserved. In the CHF group, both emotion recognition performance and ToM ability correlated moderately with global cognition (r = .38, p = .034; r = .49, p = .005, respectively), but not with executive function or verbal memory.

Conclusion

CHF patients with lower cognitive ability were more likely to have difficulty recognizing emotions and inferring the mental states of others. Clinical implications of these findings are discussed.  相似文献   
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