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41.

Introduction  

The objectives of this study were to determine small arterial elasticity (SAE) in systemic lupus erythematosus (SLE) and to investigate its relationship with intima media thickness (IMT), accumulation of advanced glycation end products (AGEs), endothelial activation and inflammation.  相似文献   
42.
Use of spectral analysis to test hypotheses on the origin of pinnipeds   总被引:6,自引:4,他引:6  
The evolutionary origin of the pinnipeds (seals, sea lions, and walruses) is still uncertain. Most authors support a hypothesis of a monophyletic origin of the pinnipeds from a caniform carnivore. A minority view suggests a diphyletic origin with true seals being related to the mustelids (otters and ferrets). The phylogenetic relationships of the walrus to other pinniped and carnivore families are also still particularly problematic. Here we examined the relative support for mono- and diphyletic hypotheses using DNA sequence data from the mitochondrial small subunit (12S) rRNA and cytochrome b genes. We first analyzed a small group of taxa representing the three pinniped families (Phocidae, Otariidae, and Odobenidae) and caniform carnivore families thought to be related to them. We inferred phylogenetic reconstructions from DNA sequence data using standard parsimony and neighbor-joining algorithms for phylogenetic inference as well as a new method called spectral analysis (Hendy and Penny) in which phylogenetic information is displayed independently of any selected tree. We identified and compensated for potential sources of error known to lead to selection of incorrect phylogenetic trees. These include sampling error, unequal evolutionary rates on lineages, unequal nucleotide composition among lineages, unequal rates of change at different sites, and inappropriate tree selection criteria. To correct for these errors, we performed additional transformations of the observed substitution patterns in the sequence data, applied more stringent structural constraints to the analyses, and included several additional taxa to help resolve long, unbranched lineages in the tree. We find that there is strong support for a monophyletic origin of the pinnipeds from within the caniform carnivores, close to the bear/raccoon/panda radiation. Evidence for a diphyletic origin was very weak and can be partially attributed to unequal nucleotide compositions among the taxa analyzed. Subsequently, there is slightly more evidence for grouping the walrus with the eared seals versus the true seals. A more conservative interpretation, however, is that the walrus is an early, but not the first, independent divergence from the common pinniped ancestor.   相似文献   
43.

Introduction

Statins (hydroxymethylglutaryl coenzyme A reductase inhibitors) are effective in reducing the risk of cardiovascular morbidity and mortality in patients with hyperlipidemia, hypertension, or type II diabetes. Next to their cholesterol-lowering activity, statins have immunomodulatory properties. Based on these properties, we hypothesized that statin use may eventually lead to dysregulation of immune responses, possibly resulting in autoimmunity. We have recently shown in an observational study that statin use was associated with an increased risk of developing rheumatoid arthritis. Our objective was to investigate whether a causal relationship could be established for this finding.

Methods

The mouse collagen type II (CII)-induced arthritis (CIA) model was used, with immunization, challenge, and euthanasia at days 0, 21, and 42, respectively. Statins were given orally before (day -28 until day 21) or after (day 21 until day 42) CIA induction. Atorvastatin (0.2 mg/day) or pravastatin (0.8 mg/day) was administered. Arthritis was recorded three times a week. Serum anti-CII autoantibodies and cytokines in supernatants from Concanavalin-A-stimulated lymph node cells and CII-stimulated spleen cells were measured.

Results

Statin administration accelerated arthritis onset and resulted in 100% arthritic animals, whereas only seven out of 12 nonstatin control animals developed arthritis. Atorvastatin administration after CIA induction resulted in earlier onset than atorvastatin administration before induction, or than pravastatin administration before or after induction. The arthritic score of animals given pravastatin before CIA induction was similar to that of the nonstatin controls, whereas the other groups that received statins showed higher arthritic scores. Atorvastatin administration, especially before CIA induction, increased anti-CII autoantibody production. IL-2 and IL-17 production by lymph node and spleen cells was higher in CIA animals than in PBS controls, but was not affected by statin administration. While IFN?? production was not affected by CIA induction, atorvastatin administration before CIA induction increased the production of this cytokine.

Conclusion

These data support previous results from our observational studies, indicating a role for statins in the induction of autoimmunity.  相似文献   
44.

Background  

Myotonic dystrophy type 1 (MD1) is one of the most prevalent neuromuscular diseases, yet very little is known about how MD1 affects the lives of couples and how they themselves manage individually and together. To better match health care to their problems, concerns and needs, it is important to understand their perspective of living with this hereditary, systemic disease.  相似文献   
45.
We developed a new and simple method to collect sections of a whole brown rice kernel for investigation of histological properties. A single kernel of rice was dehydrated through a graded ethanol series, transferred to xylene, and embedded in paraffin. During sectioning of the blocks using a rotary microtome, we used a special adhesive tape to collect and place the sections on slides so they remained flat. The use of the adhesive tape technique combined with autofluorescence characteristics allowed us to visualize cell walls throughout an entire longitudinal or transverse section of a whole rice kernel. We obtained scanning electron microscopy images of the sections to determine section quality.  相似文献   
46.

Background  

Suitable biomarkers associated with the development of delirium are still not known. Urinary proteomics has successfully been applied to identify novel biomarkers associated with various disease states, but its value has not been investigated in delirium patients.  相似文献   
47.
Wegener's granulomatosis (WG) is a form of systemic vasculitis. It is characterized by granulomatous inflammation in the upper and lower airways, vasculitis and necrotizing glomerulonephritis, and is strongly associated with antineutrophil cytoplasmic antibodies against proteinase 3. Since the etiology of the disease is not clear, treatment, consisting of corticosteroids and immunosuppressives, is nonspecific and associated with severe side effects. Pinpointing the trigger(s) of the disease would highly improve treatment. Clinical evidence shows that an infectious agent, the bacterium Staphylococcus aureus, is a risk factor for disease relapse, suggesting its involvement in the pathogenesis of WG. Here we review both clinical and experimental data that either indicate or support a role for S. aureus in WG.  相似文献   
48.
The molecular mechanisms by which plants sense their micronutrient status, and adapt to their environment in order to ensure a sufficient micronutrient supply, are poorly understood. Zinc is an essential micronutrient for all living organisms. when facing a shortage in zinc supply, plants adapt by enhancing the zinc uptake capacity. The molecular regulators controlling this adaptation were recently identified. in this mini-review, we highlight recent progress in understanding the adaptation to zinc deficiency in plants and discuss the future challenges to fully unravel its molecular basis.Key words: adaptation, zinc deficiency, biofortification, molecular regulators, plant nutritionIn an increasingly populated world, agricultural production is an essential element of social development. Agriculture is the primary source of all nutrients required for human life, and nutrient sufficiency is the basis for good health and welfare of the human population.1 Soils with zinc deficiency are widespread in the world, affecting large areas of cultivated soils in India, Turkey, China, Brazil and Australia,2,3 making zinc the most common crop micronutrient deficiency.4 In addition, risk of inadequate zinc diet and zinc malnutrition are estimated to affect one-third of the global human population, i.e., around two billion people.5 Most affected are people living in developing countries, where diets are rich in cereal-based foods. Cereal grains are rich in phytate, which is a potent anti-nutrient, limiting micronutrient bioavailability.6 Zinc deficiency in crop production can be easily ameliorated through zinc fertilization, making agronomic biofortification an important strategy,3 however in the poorer regions, the required infrastructure to provide a reliable supply of zinc fertilizers of sufficient quality, is often not available. In those situations, biofortified crops, in which the zinc status of crops is genetically improved by selective breeding or via biotechnology, offer a rural-based intervention that will more likely reach the population.7 Different traits can be targeted to developing such improved crops, such as plant zinc deficiency tolerance, zinc use efficiency and the accumulation of zinc in edible parts. However, insufficient knowledge on the molecular mechanisms and the regulation of the zinc homeostasis network in plants is a serious bottleneck when pursuing zinc biofortification.  相似文献   
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