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1.
Between 1971 and 1975, Fascioloides magna was found in 46 of 67 (69%) feral swine (Sus scrofa) in southern Texas. Flukes were recovered from swine in areas where F. magna commonly has been recovered from white-tailed deer and cattle. One to 12 flukes were recovered from each infected animal. Their presence was indicated by black hematin pigment on the liver and various other internal organs. Eggs were not detected in the gallbladder or feces of infected animals although mature flukes and eggs were recovered in the livers suggesting that, like cattle, feral swine can be infected but are aberrant hosts for the parasite and do not disseminate eggs. 相似文献
2.
Kube D Schmidt D Mörmann M Uhlemann AC Tomiuk J Tesch H Kremsner PG 《European cytokine network》2001,12(3):537-544
Interleukin-10 (IL-10) is an important immunoregulatory cytokine influencing many aspects of the adaptive and inflammatory immune response. Two dinucleotide repeats have been identified in the 5'-UTR of IL-10 and shown to be useful genetic markers in several diseases. A simple, two-colour fluorescence assay was developed for determination of microsatellite fragment length by an automatic sequencer. Using this method polymorphisms at the IL-10G and IL-10R loci of the 5' flanking region of the IL-10 gene can be identified simultaneously. A unified standard nomenclature was applied to the known IL-10G and IL-10R microsatellites. The multiplex PCR approach was used to compare the allele frequencies in two independent donor groups from Germany (Caucasian), comprising 112 and 106 cases, respectively, and one group from Gabon (African) including 91 donors. Significant differences in the allele distribution were found. Both Caucasian populations tested showed no significant differences in their allele and genotype distribution. Whereas in Africans, allele IL-10G25 is rare at 3% compared to 21% in Caucasian, alleles IL-10G22 and G23 are more prevalent in Africans than in Caucasians (22% versus 10% and 26% versus 7%, respectively). Within the IL-10R locus, the allele R13 was observed at 88% in the African group compared to 69% in Caucasians. These data may help immunogenetic studies in diseases, where IL-10 is thought to be deregulated. 相似文献
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4.
Kleppe R Uhlemann K Knappskog PM Haavik J 《The Journal of biological chemistry》1999,274(47):33251-33258
Human phenylalanine hydroxylase was expressed and purified from Escherichia coli as a fusion protein with maltose-binding protein. After removal of the fusion partner, the effects of increasing urea concentrations on enzyme activity, aggregation, unfolding, and refolding were examined. At pH 7.50, purified human phenylalanine hydroxylase is transiently activated in the presence of 0-4 M urea but slowly inactivated at higher denaturant concentrations. Intrinsic tryptophan fluorescence spectroscopy showed that the enzyme is denatured through at least two distinct transitions. The presence of phenylalanine (L-Phe) shifts the transition midpoint of the first transition from 1.4 to 2.7 M urea, whereas the second transition is unaffected by this substrate. Apparently the free energy of denaturation was almost identical for the free enzyme and for the enzyme-substrate complex, but significant differences in dDeltaG(D)/d[urea] (m(D) values) were observed for the first denaturation transition. In the absence of substrate, a high rate of non-covalent aggregation was observed for the enzyme in the presence of 1-4 M urea. All three tryptophan residues in the enzyme (Trp-120, Trp-187, and Trp-326) were mutated to phenylalanine, either as single mutations or in combination, in order to identify the residues involved in the spectroscopic transitions. A gradual dissociation of the native tetrameric enzyme to increasingly denatured dimeric and monomeric forms was demonstrated by size exclusion chromatography in the presence of denaturants. 相似文献
5.
6.
Melek Güler-Yüksel Naomi B Klarenbeek Yvonne PM Goekoop-Ruiterman Jeska K de Vries-Bouwstra Sjoerd M van der Kooij Andreas H Gerards H Karel Ronday Tom WJ Huizinga Ben AC Dijkmans Cornelia F Allaart Willem F Lems 《Arthritis research & therapy》2010,12(3):R96
Introduction
To investigate whether accelerated hand bone mineral density (BMD) loss is associated with progressive joint damage in hands and feet in the first year of rheumatoid arthritis (RA) and whether it is an independent predictor of subsequent progressive total joint damage after 4 years.Methods
In 256 recent-onset RA patients, baseline and 1-year hand BMD was measured in metacarpals 2-4 by digital X-ray radiogrammetry. Joint damage in hands and feet were scored in random order according to the Sharp-van der Heijde method at baseline and yearly up to 4 years.Results
68% of the patients had accelerated hand BMD loss (>-0.003 g/cm2) in the first year of RA. Hand BMD loss was associated with progressive joint damage after 1 year both in hands and feet with odds ratios (OR) (95% confidence intervals [CI]) of 5.3 (1.3-20.9) and 3.1 (1.0-9.7). In univariate analysis, hand BMD loss in the first year was a predictor of subsequent progressive total joint damage after 4 years with an OR (95% CI) of 3.1 (1.3-7.6). Multivariate analysis showed that only progressive joint damage in the first year and anti-citrullinated protein antibody positivity were independent predictors of long-term progressive joint damage.Conclusions
In the first year of RA, accelerated hand BMD loss is associated with progressive joint damage in both hands and feet. Hand BMD loss in the first year of recent-onset RA predicts subsequent progressive total joint damage, however not independent of progressive joint damage in the first year. 相似文献7.
Fischer-344 (F-344) rats differ from other common rat strains in that they
fail to show any preference for NaCl at any concentration in two- bottle
preference tests. Because 100 microM amiloride partially blocks the
NaCl-evoked chorda tympani (CT) response in electrophysiological studies,
we tested NaCl preference (0.068-0.273 M) in F-344 rats with and without
100 microM amiloride solution as the solvent. A third group was tested with
unadulterated NaCl solutions following CT transection. Amiloride had no
significant effect on the NaCl preference-aversion function, whereas CT
transection significantly reduced NaCl avoidance. These results suggest
that the amiloride-sensitive component of the NaCl response is not
necessary for F-344 rats to display avoidance of NaCl, but the entire CT
input is.
相似文献
8.
Determining the quality and complexity of next-generation sequencing data without a reference genome
Seyed Yahya Anvar Lusine Khachatryan Martijn Vermaat Michiel van Galen Irina Pulyakhina Yavuz Ariyurek Ken Kraaijeveld Johan T den Dunnen Peter de Knijff Peter AC ’t Hoen Jeroen FJ Laros 《Genome biology》2014,15(12)
We describe an open-source kPAL package that facilitates an alignment-free assessment of the quality and comparability of sequencing datasets by analyzing k-mer frequencies. We show that kPAL can detect technical artefacts such as high duplication rates, library chimeras, contamination and differences in library preparation protocols. kPAL also successfully captures the complexity and diversity of microbiomes and provides a powerful means to study changes in microbial communities. Together, these features make kPAL an attractive and broadly applicable tool to determine the quality and comparability of sequence libraries even in the absence of a reference sequence. kPAL is freely available at https://github.com/LUMC/kPAL.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0555-3) contains supplementary material, which is available to authorized users. 相似文献9.
Nair S Nash D Sudimack D Jaidee A Barends M Uhlemann AC Krishna S Nosten F Anderson TJ 《Molecular biology and evolution》2007,24(2):562-573
When selection is strong and beneficial alleles have a single origin, local reductions in genetic diversity are expected. However, when beneficial alleles have multiple origins or were segregating in the population prior to a change in selection regime, the impact on genetic diversity may be less clear. We describe an example of such a "soft" selective sweep in the malaria parasite Plasmodium falciparum that involves adaptive genome rearrangements. Amplification in copy number of genome regions containing the pfmdr1 gene on chromosome 5 confer resistance to mefloquine and spread rapidly in the 1990s. Using flanking microsatellite data and real-time polymerase chain reaction determination of copy number, we show that 5-15 independent amplification events have occurred in parasites on the Thailand/Burma border. The amplified genome regions (amplicons) range in size from 14.7 to 49 kb and contain 2-11 genes, with 2-4 copies arranged in tandem. To examine the impact of drug selection on flanking variation, we genotyped 48 microsatellites on chromosome 5 in 326 parasites from a single Thai location. Diversity was reduced in a 170- to 250-kb (10-15 cM) region of chromosomes containing multiple copies of pfmdr1, consistent with hitchhiking resulting from the rapid recent spread of selected chromosomes. However, diversity immediately flanking pfmdr1 is reduced by only 42% on chromosomes bearing multiple amplicons relative to chromosomes carrying a single copy. We highlight 2 features of these results: 1) All amplicon break points occur in monomeric A/T tracts (9-45 bp). Given the abundance of these tracts in P. falciparum, we expect that duplications will occur frequently at multiple genomic locations and have been underestimated as drivers of phenotypic evolution in this pathogen. 2) The signature left by the spread of amplified genome segments is broad, but results in only limited reduction in diversity. If such "soft" sweeps are common in nature, statistical methods based on diversity reduction may be inefficient at detecting evidence for selection in genome-wide marker screens. This may be particularly likely when mutation rate is high, as appears to be the case for gene duplications, and in pathogen populations where effective population sizes are typically very large. 相似文献
10.
Stefan TG Bruijnen Mignon AC van der Weijden Joannes P Klein Otto S Hoekstra Ronald Boellaard J Christiaan van Denderen Ben AC Dijkmans Alexandre E Voskuyl Irene E van der Horst-Bruinsma Conny J van der Laken 《Arthritis research & therapy》2012,14(2):R71