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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   
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Crystallography driven optimisation of a lead derived from similarity searching of the GSK compound collection resulted in the discovery of quinoline-3-carboxamides as highly potent and selective inhibitors of phosphodiesterase 4B. This series has been optimized to GSK256066, a potent PDE4B inhibitor which also inhibits LPS induced production of TNF-α from isolated human peripheral blood mononuclear cells with a pIC50 of 11.1. GSK256066 also has a suitable profile for inhaled dosing.  相似文献   
5.
Recognition of genetic structure of populations and the ability to identify vulnerable populations is useful for the formation of conservation management strategies for plants. Eucalyptus grandis is a tall forest tree that has a major area of occurrence in subtropical eastern Australia, with smaller populations located in the east coast tropics. Many widespread forest species exhibit population differentiation that corresponds to geographic regions. However, Eucalyptus grandis appears to be an exception based on isozyme and morphological data. This is intriguing given a large discontinuity between northern populations and those in the southern part of the species range. In this study, the distribution of a maternally inherited chloroplast locus was examined because it was more likely to reveal genetic structure due to the slower evolution of the chloroplast genome and limited dispersal of seed in eucalypts. As expected, the G ST for chloroplast DNA was higher than that for nuclear DNA but indicated low population differentiation for a forest tree species. Phylogeographic analysis indicated that the 15 populations grouped into three broad geographical regions; however, overall population structure was weak suggesting that the large geographical disjunction in the distribution of E. grandis may be relatively recent. A paradigm for conservation management of E. grandis based on chloroplast DNA haplotype distribution would take into account the low differentiation among populations.  相似文献   
6.
Background. Bismuth is widely used for the eradication of H. pylori , especially in developing countries, although there are concerns over its neurotoxicity. Whether bismuth has to be absorbed in humans to act against H. pylori is not known. In this study, we compared "absorbable" (colloidal bismuth subcitrate) and "nonabsorbable" (bismuth subnitrate) bismuth as part of triple therapy in the eradication of H. pylori.
Materials and Methods. A double-blind, randomized, placebo-controlled trial was carried out with 120 H. pylori –positive patients with nonulcer dyspepsia. Group CBS + Ab (n = 35) received colloidal bismuth subcitrate (one tablet qds), amoxicillin (500 mg qds), and metronidazole (400 mg tds). Group BSN + Ab (n = 35) received bismuth subnitrate (two tablets tds) and the same antibiotics. Group Ab (n = 35) received placebo bismuth (two tablets tds) and the antibiotics. Group BSN (n = 15) received bismuth subnitrate (two tablets tds) and placebo antibiotics. Bismuth was taken for 4 weeks and the antibiotics for the first 2 weeks. H. pylori eradication, side effects, compliance, pre- and post-treatment symptom scores, and bismuth absorption were assessed.
Results. H. pylori eradication was 69%, 83%, 31%, and 0% in CBS + Ab, BSN + Ab, Ab, and BSN, respectively. Side effects, compliance, and symptom relief were similar in all groups, but blood bismuth levels were significantly greater in CBS + Ab than the other three groups.
Conclusion. The efficacy of bismuth-based therapies as part of triple therapy in the eradication of H. pylori is unrelated to absorption. Hence, the use of effective but poorly absorbed bismuth preparations should be encouraged for bismuth-based eradication therapies.  相似文献   
7.

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   
8.
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   
9.
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   
10.

Introduction

Positron Emission Tomography - Computer Tomography (PET-CT) is an interesting imaging technique to visualize Ankylosing Spondylitis (AS) activity using specific PET tracers. Previous studies have shown that the PET tracers [18F]FDG and [11C](R)PK11195 can target inflammation (synovitis) in rheumatoid arthritis (RA) and may therefore be useful in AS. Another interesting tracer for AS is [18F]Fluoride, which targets bone formation. In a pilot setting, the potential of PET-CT in imaging AS activity was tested using different tracers, with Magnetic Resonance Imaging (MRI) and conventional radiographs as reference.

Methods

In a stepwise approach different PET tracers were investigated. First, whole body [18F]FDG and [11C](R)PK11195 PET-CT scans were obtained of ten AS patients fulfilling the modified New York criteria. According to the BASDAI five of these patients had low and five had high disease activity. Secondly, an extra PET-CT scan using [18F]Fluoride was made of two additional AS patients with high disease activity. MRI scans of the total spine and sacroiliac joints were performed, and conventional radiographs of the total spine and sacroiliac joints were available for all patients. Scans and radiographs were visually scored by two observers blinded for clinical data.

Results

No increased [18F]FDG and [11C](R)PK11195 uptake was noticed on PET-CT scans of the first 10 patients. In contrast, MRI demonstrated a total of five bone edema lesions in three out of 10 patients. In the two additional AS patients scanned with [18F]Fluoride PET-CT, [18F]Fluoride depicted 17 regions with increased uptake in both vertebral column and sacroiliac joints. In contrast, [18F]FDG depicted only three lesions, with an uptake of five times lower compared to [18F]Fluoride, and again no [11C](R)PK11195 positive lesions were found. In these two patients, MRI detected nine lesions and six out of nine matched with the anatomical position of [18F]Fluoride uptake. Conventional radiographs showed structural bony changes in 11 out of 17 [18F]Fluoride PET positive lesions.

Conclusions

Our PET-CT data suggest that AS activity is reflected by bone activity (formation) rather than inflammation. The results also show the potential value of PET-CT for imaging AS activity using the bone tracer [18F]Fluoride. In contrast to active RA, inflammation tracers [18F]FDG and [11C](R)PK11195 appeared to be less useful for AS imaging.  相似文献   
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