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81.
Pathologic lesions were summarized in 18 free-ranging cervids (15 moose [Alces alces], two roe deer [Capreolus capreolus], and one red deer [Cervus elaphus]) diagnosed with malignant catarrhal fever (MCF) after examination at the National Veterinary Institute, Oslo 1982-2005. Eye lesions (conjunctivitis, corneal opacity, fibrin clots in the anterior eye chamber) were the most frequent gross finding. Erosive-ulcerative mucosal lesions in the nose and mouth were also commonly found. Histopathology revealed a nonpurulent vasculitis and perivasculitis in the central nervous system (CNS) typical of MCF in 16 of the cases. The diagnosis in the remaining two animals was based upon histologic eye lesions consistent with MCF (CNS not available for examination). Polymerase chain reaction was run on samples from 15 individuals for evidence of MCF-virus DNA, and ovine herpesvirus-2 (OvHV-2) DNA was detected in five moose, one roe deer, and one red deer, and caprine herpesvirus-2 (CpHV-2) DNA was detected in two moose and one roe deer. Sera from 1,000 free-ranging cervids were tested for specific antibodies to MCF-associated viruses (MCFV) by competitive inhibition enzyme-linked immunosorbent assay. The seroprevalences were: red deer 5%, reindeer (Rangifer tarandus) 4%, roe deer 2%, and moose 0.4% (n = 250 for all four species). The results indicate that sheep and goat MCFV may cause serious disease in wild moose, roe deer, and red deer. The seropositive cervids most likely represent individuals infected with either OvHV-2 or CpHV-2, but may also reflect infections with other related MCFV.  相似文献   
82.
Expanded bed adsorption (EBA) is an integrative step in downstream processing allowing the direct capture of target proteins from cell-containing feedstocks. Extensive co-adsorption of biomass, however, may hamper the application of this technique. The latter is especially observed at anion exchange processes as cells or cell debris are negatively charged under common anion exchange conditions. The restrictions observed under these conditions are, however, directly related to processing steps prior to fluidised bed application. In this study, it could be shown that the effective surface charge of cell debris obtained during homogenisation is closely related to the debris size and thus to the homogenisation method and conditions. The amount and thus effect of cells binding to the adsorbent could be significantly decreased when optimising the homogenisation step not only towards optimal product release but towards a reduction of debris size and charge. The lower size and charge of the debris results not only in a reduced retention probability but also, in a lower collision probability between debris and adsorbent. The applicability was shown in an example where the homogenisation conditions of E. coli were optimised towards EBA applications. In a previous report (Reichert et al., 2001) studying the suitability of EBA for the capture of formate dehydrogenate from E. coli homogenate the pseudo affinity resin Streamline Red was identified as the only suitable adsorbent. The new approach, however, led to a system where anion exchange as capture step became possible, however, to the cost of binding capacity.  相似文献   
83.
Tuesuwan B  Kerwin SM 《Biochemistry》2006,45(23):7265-7276
Diradical-generating cyclizations such as the enediyne Bergman cyclization and the enyne allene Myers-Saito cyclization have been exploited by nature in the mechanism of DNA cleavage by a series of potent antitumor antibiotics. Alternative diradical-generating cyclizations have been proposed in the design of selective antitumor agents; however, little information is available concerning the utility of these alternative cyclizations in radical-based DNA cleavage chemistry. One such alternative diradical-generating cyclization, the aza-Myers-Saito cyclization of aza-enyne allenes that are derived from base-promoted isomerization of skipped aza-enediynes, has been recently reported. Here, we report the synthesis and DNA cleavage chemistry of a series of pyridinium skipped aza-enediynes (2-alkynyl-N-propargyl pyridinium salts). Efficient DNA cleavage requires the presence of the skipped aza-enediyne functionality, and optimal DNA cleavage occurs at basic pH. Within this series of compounds, the analogue bearing a p-methoxyphenyl group on the pyridinium 2-alkyne substituents was found to be the most effective DNA cleavage agent, displaying significant supercoiled DNA-nicking activity at concentrations as low as 1 microM. Detailed studies of this analogue show that DNA cleavage occurs through 4'-hydrogen-atom abstraction from the DNA backbone and oxidation of guanine bases. This is the first report of enediyne-like radical-based DNA cleavage by an agent designed to undergo an alternative diradical-generating cyclization.  相似文献   
84.
doi: 10.1111/j.1741‐2358.2011.00562.x
Attitudes to and knowledge about oral health care among nursing home personnel – an area in need of improvement Background: In 1999, a dental reform became law in Sweden that regulated both dental care to dependent individuals and training in oral health care for nursing home personnel. Substantial resources have been channelled into these efforts, but the outcome of these efforts has not been evaluated. The aim of this study was to explore attitudes to and knowledge about oral health care among nursing home personnel more than 5 years after the law was adopted, that being 2005. Methods: A total of 454 individuals employed at nursing homes answered a questionnaire of 16 multiple‐choice items concerning attitudes to and knowledge about oral health care. Results: Eighty‐nine per cent considered oral health care to be an important part of good nursing. The answers indicated problems, however, when it came to its implementation and knowledge, and 35% stated that they had had no formal education in oral health care. Conclusions: Despite generally positive oral health care attitudes, it is important that oral health care education is available to and made of interest for all nursing home personnel, especially in light of the increase in number of natural teeth and frequency of crowns and bridges among dependent elderly.  相似文献   
85.
? Premise of the Study: Climate change forces many species to migrate. Empirical small-scale data on migration and colonization in the Arctic are scarce. Retreating glaciers provide new territory for cold-adapted plant species, but the genetic consequences depend on dispersal distances and frequencies. We estimated local, regional, and long-distance dispersal frequencies, as well as their effect on levels of genetic diversity, in diploid and tetraploid individuals of Saxifraga oppositifolia. ? Methods: Samples were collected in four aged moraines in each of three glacier forelands, in surrounding areas and reference populations in the Arctic archipelago Svalbard. These samples were analyzed for neutral amplified fragment length polymorphisms (AFLPs, n = 707) and ploidy levels (n = 30). ? Key Results: Genetic clustering and ploidy analyses revealed two distinct genetic groups representing diploids and tetraploids, with few intermediate triploids. The groups were intermixed in most sampled populations. No differences in genetic diversity were found between tetraploids and diploids, or between established and glacier foreland populations. Seeds were dispersed over local, regional, and long distances, with the highest proportions of seeds originating from close sources. A minimum of 4-15 founding individuals from several source populations had initially established in each glacier foreland. ? Conclusions: Our data suggest that S. oppositifolia can rapidly colonize new deglaciated areas without losing genetic diversity. Thus, glacier forelands can be alternative habitats for cold-adapted vascular plants tracking their climatic niche. Our data show no difference in colonization success between diploid and tetraploid individuals.  相似文献   
86.
87.
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a devastating inherited disorder characterized by episodic syncope and/or sudden cardiac arrest during exercise or acute emotion in individuals without structural cardiac abnormalities. Although rare, CPVT is suspected to cause a substantial part of sudden cardiac deaths in young individuals. Mutations in RYR2, encoding the cardiac sarcoplasmic calcium channel, have been identified as causative in approximately half of all dominantly inherited CPVT cases. Applying a genome-wide linkage analysis in a large Swedish family with a severe dominantly inherited form of CPVT-like arrhythmias, we mapped the disease locus to chromosome 14q31-32. Sequencing CALM1 encoding calmodulin revealed a heterozygous missense mutation (c.161A>T [p.Asn53Ile]) segregating with the disease. A second, de novo, missense mutation (c.293A>G [p.Asn97Ser]) was subsequently identified in an individual of Iraqi origin; this individual was diagnosed with CPVT from a screening of 61 arrhythmia samples with no identified RYR2 mutations. Both CALM1 substitutions demonstrated compromised calcium binding, and p.Asn97Ser displayed an aberrant interaction with the RYR2 calmodulin-binding-domain peptide at low calcium concentrations. We conclude that calmodulin mutations can cause severe cardiac arrhythmia and that the calmodulin genes are candidates for genetic screening of individual cases and families with idiopathic ventricular tachycardia and unexplained sudden cardiac death.  相似文献   
88.
Numerous fungal morphospecies include cryptic species that routinely are detected by sequencing a few unlinked DNA loci. However, whether the patterns observed by multi-locus sequencing are compatible with genome wide data, such as amplified fragment length polymorphisms (AFLPs), is not well known for fungi. In this study we compared the ability of three DNA loci and AFLP data to discern between cryptic fungal lineages in the three morphospecies Coniophora olivacea, Coniophora arida, and Coniophora puteana. The sequences and the AFLP data were highly congruent in delimiting the morphotaxa into multiple cryptic species. However, while the DNA sequences indicated introgression or hybridization between some of the cryptic lineages the AFLP data did not. We conclude that as few as three polymorphic DNA loci was sufficient to recognize cryptic lineages within the studied Coniophora taxa. However, based on analyses of a few (three) sequenced loci the hybridization could not easily be distinguished from incomplete lineage sorting. Hence, great caution should be taken when concluding about hybridization based on data from just a few loci.  相似文献   
89.

Background

Dietary fish oil, rich in n-3 fatty acids (n-3 FAs), e.g. docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), regulate inflammatory reactions by various mechanisms, e.g. gene activation. However, the effects of long-term treatment with DHA and EPA in humans, using genome wide techniques, are poorly described. Hence, our aim was to determine the effects of 6 mo of dietary supplementation with an n-3 FA preparation rich in DHA on global gene expression in peripheral blood mononuclear cells.

Methods and Findings

In the present study, blood samples were obtained from a subgroup of 16 patients originating from the randomized double-blind, placebo-controlled OmegAD study, where 174 Alzheimer disease (AD) patients received daily either 1.7 g of DHA and 0.6 g EPA or placebo for 6 months. In blood samples obtained from 11 patients receiving n-3 FA and five placebo, expressions of approximately 8000 genes were assessed by gene array. Significant changes were confirmed by real-time PCR. At 6 months, the n-3 FAs group displayed significant rises of DHA and EPA plasma concentrations, as well as up- and down-regulation of nine and ten genes, respectively, was noticed. Many of these genes are involved in inflammation regulation and neurodegeneration, e.g. CD63, MAN2A1, CASP4, LOC399491, NAIP, and SORL1 and in ubiqutination processes, e.g. ANAPC5 and UBE2V1. Down-regulations of ANAPC5 and RHOB correlated to increases of plasma DHA and EPA levels.

Conclusions

We suggest that 6 months of dietary n-3 FA supplementation affected expression of genes that might influence inflammatory processes and could be of significance for AD.

Trial Registration

ClinicalTrials.gov NCT00211159  相似文献   
90.
Monkeypox virus (MPXV) causes a smallpox-like disease in humans. Clinical and epidemiological studies provide evidence of pathogenicity differences between two geographically distinct monkeypox virus clades: the West African and Congo Basin. Genomic analysis of strains from both clades identified a ~10 kbp deletion in the less virulent West African isolates sequenced to date. One absent open reading frame encodes the monkeypox virus homologue of the complement control protein (CCP). This modulatory protein prevents the initiation of both the classical and alternative pathways of complement activation. In monkeypox virus, CCP, also known as MOPICE, is a ~24 kDa secretory protein with sequence homology to this superfamily of proteins. Here we investigate CCP expression and its role in monkeypox virulence and pathogenesis. CCP was incorporated into the West African strain and removed from the Congo Basin strain by homologous recombination. CCP expression phenotypes were confirmed for both wild type and recombinant monkeypox viruses and CCP activity was confirmed using a C4b binding assay. To characterize the disease, prairie dogs were intranasally infected and disease progression was monitored for 30 days. Removal of CCP from the Congo Basin strain reduced monkeypox disease morbidity and mortality, but did not significantly decrease viral load. The inclusion of CCP in the West African strain produced changes in disease manifestation, but had no apparent effect on disease-associated mortality. This study identifies CCP as an important immuno-modulatory protein in monkeypox pathogenesis but not solely responsible for the increased virulence seen within the Congo Basin clade of monkeypox virus.  相似文献   
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