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31.
Ahlehoff O Skov L Gislason G Lindhardsen J Kristensen SL Iversen L Lasthein S Gniadecki R Dam TN Torp-Pedersen C Hansen PR 《PloS one》2012,7(4):e36342
Background
Patients with psoriasis have increased prevalence of coronary risk factors and limited recent results have suggested that these risk factors are undertreated in patients with psoriasis. This may contribute to the increased risk of cardiovascular diseases observed in patients with psoriasis.Objective
To examine the pharmacological treatment of coronary risk factors in patients with severe psoriasis treated with biologic agents in a real-world setting.Methods and Findings
Medical history of patients with severe psoriasis treated with biologic agents in the time period 2007–09 was retrieved from a Danish nationwide registry (DERMBIO). Individual-level linkage of nationwide administrative registries of hospitalizations, concomitant medications, and socioeconomic status was performed to gain insights into the use of pharmacological treatment. A total of 693 patients (mean age 46.1±12.7 years, 65.7% male) with severe psoriasis treated with biologic agents were identified. Hypertension, hypercholesterolemia, and diabetes mellitus were identified in 16.6%, 9.2%, and 6.7% of cases, respectively. Patients with severe psoriasis were significantly less likely to receive cardiovascular pharmacotherapy compared to age, sex, and coronary risk factor matched controls. In psoriatic patients with hypertension 27.7% received no antihypertensive pharmacotherapy. Patients with dyslipidemia received cholesterol-lowering medications in 55.8% of cases and patients with diabetes mellitus received angiotensin converting enzyme inhibitors/angiotensin II receptor blockers and cholesterol-lowering medications in 42.1% and 23.7% of cases, respectively. Similar results were found for the subset of patients with >1 coronary risk factor and for high risk patients with established atherosclerotic disease.Conclusion
This nationwide study of patients with severe psoriasis demonstrated substantial undertreatment of coronary risk factors. Increased focus on identifying cardiovascular risk factors and initiation of preventive cardiovascular pharmacotherapy in patients with psoriasis is warranted. 相似文献32.
We have studied the changes in the activities of both nitrogenase (switch off) and glutamine synthetase in Rhodospirillum rubrum upon addition of ammonium ions or glutamine to nitrogen fixing cultures. Both activities decrease drastically and return in a parallel manner when added ammonia is metabolized. The decrease in glutamine synthetase activity does not seem to be primarily due to adenylylation of the enzyme. Addition of glutamine to cells starved for nitrogen results in inactivation of glutamine synthetase but nitrogenase is only partially switched off.Abbreviations CeMe3NBr
Cetyltrimethylammonium bromide
- Hepes
N-2-hydroxyethyl-piperazine-N-2 sulfonic acid
- MSO
methionine-D,L-sulfoximine
- Tea-Dmg
triethanol amine-3,3-dimethylglutaric acid 相似文献
33.
Frankia KB5 Possesses a Hydrogenase Immunologically Related to Membrane-Bound [NiFe]-Hydrogenases 总被引:1,自引:0,他引:1
The immunological relationship of the hydrogenase in Frankia KB5 to hydrogenases in other microorganisms was investigated using antisera raised against holo-[NiFe]-hydrogenases isolated
from Alcaligenes latus, Azotobacter vinelandii, Ralstonia eutropha, and the small and large hydrogenase subunits from Bradyrhizobium japonicum. The antisera raised against the A. latus, R. eutropha, and B. japonicum (large subunit) polypeptides were found to recognize two polypeptides, corresponding to the unprocessed and processed forms
of the hydrogenase subunit in Frankia KB5. None of the antisera, including the antibodies produced against the small hydrogenase subunit isolated from B. japonicum, recognized any polypeptide related to the small hydrogenase subunit in Frankia KB5. An immunogold localization study of the intracellular distribution of hydrogenase in Frankia KB5, with the cryo-section technique, showed that labeling in the membrane of both hyphae and vesicles was positively correlated
with hydrogenase activity.
Received: 6 November 2000 / Accepted: 18 December 2000 相似文献
34.
Gunnar Brehm Paul D. N. Hebert Robert K. Colwell Marc-Oliver Adams Florian Bodner Katrin Friedemann Lars M?ckel Konrad Fiedler 《PloS one》2016,11(3)
We sampled 14,603 geometrid moths along a forested elevational gradient from 1020–3021 m in the southern Ecuadorian Andes, and then employed DNA barcoding to refine decisions on species boundaries initially made by morphology. We compared the results with those from an earlier study on the same but slightly shorter gradient that relied solely on morphological criteria to discriminate species. The present analysis revealed 1857 putative species, an 80% increase in species richness from the earlier study that detected only 1010 species. Measures of species richness and diversity that are less dependent on sample size were more than twice as high as in the earlier study, even when analysis was restricted to an identical elevational range. The estimated total number of geometrid species (new dataset) in the sampled area is 2350. Species richness at single sites was 32–43% higher, and the beta diversity component rose by 43–51%. These impacts of DNA barcoding on measures of richness reflect its capacity to reveal cryptic species that were overlooked in the first study. The overall results confirmed unique diversity patterns reported in the first investigation. Species diversity was uniformly high along the gradient, declining only slightly above 2800 m. Species turnover also showed little variation along the gradient, reinforcing the lack of evidence for discrete faunal zones. By confirming these major biodiversity patterns, the present study establishes that incomplete species delineation does not necessarily conceal trends of biodiversity along ecological gradients, but it impedes determination of the true magnitude of diversity and species turnover. 相似文献
35.
Vikman Kristina Robertson Brita Grant Gunnar Liljeborg Anders Kristensson Krister 《Brain Cell Biology》1998,27(10):749-760
Summary Interferon-γ can facilitate the spinal nociceptive flexor reflex and elicit neuropathic pain-related behavior in rats and mice. Immunoreactivity for the interferon-γ receptor (IFN-γR) occurs in the superficial layers of the dorsal horn and the lateral spinal nucleus in the rat and mouse spinal cord, as well as in subsets of neurons in the dorsal root ganglia. The aim of the present study was to examine the cellular localization and origin of the IFN-γR in the spinal cord. As viewed by confocal microscopy, the immunopositivity for the IFN-γR was co-localized with that of the presynaptic marker synaptophysin and with neuronal nitric oxide synthase in the lateral spinal nucleus, whereas only a minor overlap with these molecules was observed in laminae I and II of the dorsal horn. There was no co-localization of the IFN-γR with markers for astrocytes and microglial cells. Ultrastructurally, the IFN-γR was found predominantly in axon terminals in the lateral spinal nucleus but also at postsynaptic sites in dendrites in laminae I and II. The IFN-γR expressed in neurons in dorsal root ganglia was transported in axons both centrally and peripherally. Hemisection of the spinal cord caused no reduction in immunolabelling of the IFN-γR in the dorsal horn or the lateral spinal nucleus. Since rhizotomy does not effect the immunolabelling in the lateral spinal nucleus, our observation indicates that the presynaptic receptors in this nucleus are derived from intrinsic neurons. The localization of the IFN-γR in the spinal cord differed from that of the AMPA glutamate receptor subunits 2 and 3 and the substance P receptor (NK1). Our results, showing localization of IFN-γR to pre- and postsynaptic sites in the dorsal horn and lateral spinal nucleus indicate that IFN-γ can modulate nociception at the spinal cord level. 相似文献
36.
Nanoporous alumina membranes were silanized with aminopropylsilane and iminodiacetic acid (IDA) groups were generated in situ by reaction with iodoacetate. The membranes were mounted in standard filter holders, connected to a HPLC system and saturated with selected metal ions. Cu(II) allowed the capture of chicken muscle lactate dehydrogenase with such stability, repeatability and reproducibility that Michaelis–Menten kinetics could be studied. The IDA surface was stable for months and could be depleted and regenerated with metal ions multiple times without appreciable loss of capacity. The binding of lactate dehydrogenase influenced the backpressure to the extent that could be expected for a monolayer according to Poiseuilles law. 相似文献
37.
Long-Term Increase in Aboveground Carbon Stocks Following Exclusion of Grazers and Forest Establishment in an Alpine Ecosystem 总被引:1,自引:0,他引:1
James D. M. Speed Vegard Martinsen Atle Mysterud Jan Mulder Øystein Holand Gunnar Austrheim 《Ecosystems》2014,17(7):1138-1150
Ecosystem stores of carbon are a key component in the global carbon cycle. Many studies have examined the impact of climate change on ecosystem carbon storage, but few have investigated the impact of land-use change and herbivory. However, land-use change is a major aspect of environmental change, and livestock grazing is the most extensive land use globally. In this study, we combine a grazing exclosure experiment and a natural experiment to test the impact of grazer exclusion on vegetation dynamics and ecosystem carbon stores in the short term (12-year exclosures), and the long term (islands inaccessible to livestock), in a heavily grazed mountain region in Norway. Following long-term absence of sheep, birch forest was present. The grazing-resistant grass Nardus stricta, dominated under long-term grazing, whilst the selected grass Deschampsia flexuosa and herb species dominated the vegetation layer in the long-term absence of sheep. The established birch forest led to vegetation carbon stocks being higher on the islands (0.56 kg C m?2 on the islands compared to 0.18 kg C m?2 where grazed) and no difference in soil carbon stocks. In the short-term exclusion of sheep, there were minor differences in carbon stocks reflecting the longer term changes. These results show that aboveground carbon stocks are higher in the long-term absence of sheep than in the continual presence of high sheep densities, associated with a vegetation state change between tundra and forest. The reduction of herbivore populations can facilitate forest establishment and increase aboveground carbon stocks, however, the sequestration rate is low. 相似文献
38.
Rembeck K Alsiö A Christensen PB Färkkilä M Langeland N Buhl MR Pedersen C Mørch K Westin J Lindh M Hellstrand K Norkrans G Lagging M 《PloS one》2012,7(1):e29370
Background and Aims
Recently, several genome-wide association studies have revealed that single nucleotide polymorphisms (SNPs) in proximity to IL28B predict spontaneous clearance of HCV infection as well as outcome following peginterferon and ribavirin therapy among HCV genotype 1 infected patients. The present study aimed to evaluate the impact of IL28B SNP variability on liver histology in the context of a phase III treatment trial (NORDynamIC) for treatment-naïve patients with chronic HCV genotype 2 or 3 infection, where pretreatment liver biopsies were mandatory.Methods
Three hundred and thirty-nine Caucasian patients had samples available for IL28B genotyping (rs12979860) of whom 314 had pretreatment liver biopsies that were evaluated using the Ishak protocol, allowing for detailed grading and staging of liver histopathology.Results
IL28B CCrs12979860 genotype in HCV genotype 3 infected patients was associated with higher ALT levels (p<0.0001), higher AST to platelet ratio index (APRI; p = 0.001), and higher baseline viral load (p<0.0001) as compared to patients with the CT or TT genotypes. Additionally the CCrs12979860 genotype entailed more pronounced portal inflammation (p = 0.02) and steatosis (p = 0.03). None of these associations were noted among HCV genotype 2 infected patients.Conclusion
This study shows that the CCrs12979860 SNP is associated with more pronounced liver histopathology in patients chronically infected with HCV genotype 3, which may be secondary to higher viral load. The finding that IL28B variability did not impact on liver pathology or viral load among genotype 2 infected patients implies that IL28B may differentially regulate the course of genotype 2 and 3 infection. 相似文献39.
Kleinau G Brehm M Wiedemann U Labudde D Leser U Krause G 《Molecular endocrinology (Baltimore, Md.)》2007,21(2):574-580
Comparison between wild-type and mutated glycoprotein hormone receptors (GPHRs), TSH receptor, FSH receptor, and LH-chorionic gonadotropin receptor is established to identify determinants involved in molecular activation mechanism. The basic aims of the current work are 1) the discrimination of receptor phenotypes according to the differences between activity states they represent, 2) the assignment of classified phenotypes to three-dimensional structural positions to reveal 3) functional-structural hot spots and 4) interrelations between determinants that are responsible for corresponding activity states. Because it is hard to survey the vast amount of pathogenic and site-directed mutations at GPHRs and to improve an almost isolated consideration of individual point mutations, we present a system for systematic and diversified sequence-structure-function analysis (http://www.fmp-berlin.de/ssfa). To combine all mutagenesis data into one set, we converted the functional data into unified scaled values. This at least enables their comparison in a rough classification manner. In this study we describe the compiled data set and a wide spectrum of functions for user-driven searches and classification of receptor functionalities such as cell surface expression, maximum of hormone binding capability, and basal as well as hormone-induced Galphas/Galphaq mediated cAMP/inositol phosphate accumulation. Complementary to known databases, our data set and bioinformatics tools allow functional and biochemical specificities to be linked with spatial features to reveal concealed structure-function relationships by a semiquantitative analysis. A comprehensive discrimination of specificities of pathogenic mutations and in vitro mutant phenotypes and their relation to signaling mechanisms of GPHRs demonstrates the utility of sequence-structure-function analysis. Moreover, new interrelations of determinants important for selective G protein-mediated activation of GPHRs are resumed. 相似文献
40.