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31.
Previous studies indicate that lumbar radicular pain following disc herniation may be associated with release of several pro-inflammatory mediators, including interleukin-1 (IL1). In the present study, we examined how genetic variability in IL1A (rs1800587 C>T), IL1B (rs1143627 T>C) and IL1RN (rs2234677 G>A) influenced the clinical outcome the first year after disc herniation. Patients (n = 258) with lumbar radicular pain due to disc herniation were recruited from two hospitals in Norway. Pain and disability were measured by visual analogue scale (VAS) and Oswestry Disability Index (ODI) over a 12 month period. The result showed that patients with the IL1A T allele, in combination with the IL1RN A allele had more pain and a slower recovery than other patients (VAS p = 0.049, ODI p = 0.059 rmANOVA; VAS p = 0.003, ODI p = 0.050 one-way ANOVA at 12 months). However, regarding the IL1B/IL1RN genotype, no clear effect on recovery was observed (VAS p = 0.175, ODI p = 0.055 rmANOVA; VAS p = 0.105, ODI p = 0.214 one-way ANOVA at 12 months). The data suggest that the IL1A T/IL1RN A genotype, but not the IL1B T/IL1RN A genotype, may increase the risk of a chronic outcome in patients following disc herniation.  相似文献   
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1.
1) The end chambers of the ovarial lobes in coreid Hemiptera contribute to the nutritive materials which are stored in the growing egg.  相似文献   
33.
Informed consent is considered by many to be a moral imperative in medical research. However, it is increasingly acknowledged that in many actual instances of consent to participation in medical research, participants do not employ the provided information in their decision to consent, but rather consent based on the trust they hold in the researcher or research enterprise. In this article we explore whether trust‐based consent is morally inferior to information‐based consent. We analyse the moral values essential to valid consent – autonomy, voluntariness, non‐manipulation, and non‐exploitation – and assess whether these values are less protected and promoted by consent based on trust than they are by consent based on information. We find that this is not the case, and thus conclude that trust‐based consent if not morally inferior to information‐based consent.  相似文献   
34.
The human selenoprotein VIMP (VCP-interacting membrane protein)/SelS (selenoprotein S) localizes to the endoplasmic reticulum (ER) membrane and is involved in the process of ER-associated degradation (ERAD). To date, little is known about the presumed redox activity of VIMP, its structure and how these features might relate to the function of the protein in ERAD. Here, we use the recombinantly expressed cytosolic region of VIMP where the selenocysteine (Sec) in position 188 is replaced with a cysteine (a construct named cVIMP-Cys) to characterize redox and structural properties of the protein. We show that Cys-188 in cVIMP-Cys forms a disulfide bond with Cys-174, consistent with the presence of a Cys174-Sec188 selenosulfide bond in the native sequence. For the disulfide bond in cVIMP-Cys we determined the reduction potential to -200 mV, and showed it to be a good substrate of thioredoxin. Based on a biochemical and structural characterization of cVIMP-Cys using analytical gel filtration, CD and NMR spectroscopy in conjunction with bioinformatics, we propose a comprehensive overall structural model for the cytosolic region of VIMP. The data clearly indicate the N-terminal half to be comprised of two extended α-helices followed by a C-terminal region that is intrinsically disordered. Redox-dependent conformational changes in cVIMP-Cys were observed only in the vicinity of the two Cys residues. Overall, the redox properties observed for cVIMP-Cys are compatible with a function as a reductase, and we speculate that the plasticity of the intrinsically disordered C-terminal region allows the protein to access many different and structurally diverse substrates.  相似文献   
35.
The 5-hydroxytryptamine (5-HT4) receptor may be implicated in depression and is a new potential target for antidepressant treatment. We have investigated the brain 5-HT4 receptor [3H]SB207145 binding in the Flinders Sensitive Line rat depression model by quantitative receptor autoradiography, and related this to 5-HT transporter ( S )-[ N -methyl-3H]citalopram binding. We also determined the regulation of 5-HT4 receptor binding by 1, 14, and 21 days of paroxetine administration and subchronic 5-HT depletion, and compared this with changes in 5-HT2A receptor [3H]MDL100907 binding. In the Flinders Sensitive Line, the 5-HT4 receptor and 5-HT transporter binding were decreased in the dorsal and ventral hippocampus, and the changes in binding were directly correlated within the dorsal hippocampus. Chronic but not acute paroxetine administration caused a 16–47% down-regulation of 5-HT4 receptor binding in all regions evaluated including the basal ganglia and hippocampus, while 5-HT depletion increased the 5-HT4 receptor binding in the dorsal hippocampus, hypothalamus, and lateral globus pallidus. In comparison, the 5-HT2A receptor binding was decreased in the frontal and cingulate cortices after chronic paroxetine administration, and markedly reduced in several regions after 5-HT depletion. Thus, the 5-HT4 receptor binding was decreased in the Flinders Sensitive Line depression model and in response to chronic paroxetine administration.  相似文献   
36.
Structures of three pectic arabinogalactans, one from Vernonia kotschyana (Vk2a) and two from Cochlospermum tinctorium (Ct50A1 and Ct50A2), and their complement fixation and induction of B cell proliferation in vitro were compared. The polysaccharide Vk2a expressed potent biological activity in both assays compared with Ct50A1 and Ct50A2. Vk2a possessed a very high molecular weight (1150 +/- 20 kDa) compared with Ct50A1 and Ct50A2 which both showed a polydisperse nature with the highest molecular weight polymers in each fraction estimated at approximately 105 kDa (Ct1a) and 640 +/- 100 kDa (Ct2a), respectively. The HMW polymers showed complement fixation in the same range as the native fractions. The arabinogalactan II content was low in Vk2a (2%) compared with that in Ct50A1 (23%) and Ct50A2 (12%). The high molecular weight polymers were subjected to digestion with a beta-d-(1, 3)-galactanase-rich fraction from Driselase, oligomers were isolated by HPAEC, and their finer structures were determined by MALDI- and ES-qoToF-MS, linkage, and monosaccharide composition analyses. Vk2a consists of both a galacturonan core and a rhamnogalacturonan core rich in neutral side chains. The backbones of both Ct-polysaccharides consist mainly of RG-I regions with numerous neutral side chains dominated by galactosyl residues, whereas the homogalacturonan regions seem to be small. Differences in the chain lengths of the 6-linked galacto-oligosaccharides attached to the 3-linked galactan core could not be related to the differences in the potencies of the biological activities observed.  相似文献   
37.
Over the last decade, the introduction of microarray technology has had a profound impact on gene expression research. The publication of studies with dissimilar or altogether contradictory results, obtained using different microarray platforms to analyze identical RNA samples, has raised concerns about the reliability of this technology. The MicroArray Quality Control (MAQC) project was initiated to address these concerns, as well as other performance and data analysis issues. Expression data on four titration pools from two distinct reference RNA samples were generated at multiple test sites using a variety of microarray-based and alternative technology platforms. Here we describe the experimental design and probe mapping efforts behind the MAQC project. We show intraplatform consistency across test sites as well as a high level of interplatform concordance in terms of genes identified as differentially expressed. This study provides a resource that represents an important first step toward establishing a framework for the use of microarrays in clinical and regulatory settings.  相似文献   
38.
We have assessed the utility of RNA titration samples for evaluating microarray platform performance and the impact of different normalization methods on the results obtained. As part of the MicroArray Quality Control project, we investigated the performance of five commercial microarray platforms using two independent RNA samples and two titration mixtures of these samples. Focusing on 12,091 genes common across all platforms, we determined the ability of each platform to detect the correct titration response across the samples. Global deviations from the response predicted by the titration ratios were observed. These differences could be explained by variations in relative amounts of messenger RNA as a fraction of total RNA between the two independent samples. Overall, both the qualitative and quantitative correspondence across platforms was high. In summary, titration samples may be regarded as a valuable tool, not only for assessing microarray platform performance and different analysis methods, but also for determining some underlying biological features of the samples.  相似文献   
39.
The concentrations of manganese, copper, and zinc in cerebrospinal fluid (CSF) from patients with multiple sclerosis (MS) and patients with no known neurological disease (control group) were measured. Manganese and copper levels were determined by two different analytical methods: atomic absorption spectrometry (AAS) and high-resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS), whereas zinc levels were determined by HR-ICP-MS only. Manganese levels (mean±SEM) were significantly decreased in the CSF of MS patients (1.07±0.13 μg/L, ICP-MS; 1.08±0.11 μg/L, AAS) compared to the levels in the control group (1.78±0.26 μg/L, ICP-MS; 1.51±0.17 μg/L, AAS). Copper levels were significantly elevated in the CSF of MS patients (10.90±1.11 μg/L; ICP-MS, 11.53±0.83 μg/L, AAS) compared to the levels in the control group (8.67±0.49 μg/L, ICP-MS; 9.10±0.62 μg/L, AAS). There were no significant differences between the CSF zinc levels of MS and control patients. The physiological basis for the differences in manganese and copper concentrations between MS patients and controls is unknown, but could be related to alterations in the manganese-containing enzyme glutamine synthetase and the copper-containing enzyme cytochrome oxidase.  相似文献   
40.
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