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21.
David F Ten Cate Jolanda J Luime Nanno Swen Andreas H Gerards Mike H De Jager Natalja M Basoski Johanna MW Hazes Cees J Haagsma Johannes WG Jacobs 《Arthritis research & therapy》2013,15(1):R4
Introduction
Ultrasonography (US) might have an added value to clinical examination in diagnosing early rheumatoid arthritis (RA) and assessing remission of RA. We aimed to clarify the added value of US in RA in these situations performing a systematic review.Methods
A systematic literature search was performed for RA, US, diagnosis and remission. Methodological quality was assessed; the wide variability in the design of studies prohibited pooling of results.Results
Six papers on the added value of US diagnosing early RA were found, in which at least bilateral metacarpophalangeal (MCP), wrists and metatarsophalangeal (MTP) joints were scanned. Compared to clinical examination, US was superior with regard to detecting synovitis and predicting progression to persistent arthritis or RA. Eleven papers on assessing remission were identified, in which at least the wrist and the MCP joints of the dominant hand were scanned. Often US detected inflammation in patients clinically in remission, irrespective of the remission criteria used. Power Doppler signs of synovitis predicted X-ray progression and future flare in patients clinically in remission.Conclusions
US appears to have added value to clinical examination for diagnosing of RA when scanning at least MCP, wrist and MTP joints, and, when evaluating remission of RA, scanning at least wrist and MCP joints of the dominant hand. For both purposes primarily power Doppler US might be used since its results are less equivocal than those of greyscale US. 相似文献22.
P. A. Vriesendorp N. M. Van Mieghem W. B. Vletter F. J. Ten Cate P. L. de Jong A. F. L. Schinkel M. Michels 《Netherlands heart journal》2013,21(5):245-248
Background
Percutaneous transluminal septal myocardial ablation using microsphere embolisation is a new interventional technique to treat patients with hypertrophic obstructive cardiomyopathy.Methods and results
In two patients, considered at high risk for myectomy, targeted septal perforators were occluded with microsphere embolisation instead of alcohol ablation to reduce left ventricular outflow gradient. In both cases the left ventricular outflow tract gradient was immediately reduced. No adverse events occurred.Conclusion
This is the first clinical experience with Embozene® Microspheres in the Netherlands as an alternative for alcohol septal ablation. In both cases it resulted in immediate improvement in the haemodynamics, without any adverse events. 相似文献23.
M Gloerich JP Ten Klooster MJ Vliem T Koorman FJ Zwartkruis H Clevers JL Bos 《Nature cell biology》2012,14(8):793-801
The microvillus brush border at the apex of the highly polarized enterocyte allows the regulated uptake of nutrients from the intestinal lumen. Here, we identify the small G protein Rap2A as a molecular link that couples the formation of microvilli directly to the preceding cell polarization. Establishment of apicobasal polarity, which can be triggered by the kinase LKB1 in single, isolated colon cells, results in enrichment of PtdIns(4,5)P(2) at the apical membrane. The subsequent recruitment of phospholipase D1 allows polarized accumulation of phosphatidic acid, which provides a local cue for successive signalling by the guanine nucleotide exchange factor PDZGEF, the small G protein Rap2A, its effector TNIK, the kinase MST4 and, ultimately, the actin-binding protein Ezrin. Thus, epithelial cell polarization is translated directly into the acquisition of brush borders through a small G protein signalling module whose action is positioned by a cortical lipid cue. 相似文献
24.
Jae-Jin Lee Yeon-Hee Lee Su-Jin Park Seung-Yeol Lee Sangkyu Park Dae Sung Lee In-Kyu Kang Leonid N. Ten Hee-Young Jung 《Antonie van Leeuwenhoek》2017,110(3):407-414
Strain 16F3HT, a Gram-negative, aerobic, non-motile, and oval-shaped bacterium, was isolated from river water collected from the Han River in South Korea. Growth of strain 16F3HT was observed at 10–42 °C (optimum at 25–30 °C), but no growth occurred at 4 °C. The strain is able to grow at pH 4–10 (optimum at pH 7–8) and tolerates up to 4% NaCl (w/v), with optimum growth at 0.5% NaCl. The isolate was found to be resistant to UV irradiation. Based on 16S rRNA gene sequence analysis, it is closely related to ‘Deinococcus seoulensis’ 16F1E (98.8%), Deinococcus aquaticus PB314T (98.1%) and Deinococcus caeni Ho-08T (98.0%). The level of DNA–DNA homology between the novel strain and the three related strains was 57.4, 41.2, and 35.8%, respectively. Chemotaxonomic data revealed that strain 16F3HT possesses MK-8 as the predominant respiratory quinone, an unidentified phosphoglycolipid as the major polar lipid, and C15:1 ω6c and C16:1 ω7c as the major fatty acids. The DNA G + C content was determined to be 65.7 mol%. Based on polyphasic evidence, strain 16F3HT (=KCTC 33794T = JCM 31406T) should be classified as the type strain of a novel Deinococcus species, for which the name Deinococcus knuensis sp. nov. is proposed. 相似文献
25.
AIMS: To develop a plate assay for simultaneous screening of polysaccharide-degrading and protein-degrading micro-organisms. METHODS AND RESULTS: A plate assay, based on the visible solubilization of small substrate particles and the formation of haloes on Petri dishes, containing a mixture of diversely coloured insoluble polysaccharides and dye-labelled collagen as chromogenic substrates, was developed. This method was successfully applied for isolating the diverse polysaccharide- and/or protein-degrading bacteria from soil and sludge samples. Selected strains were identified using 16S rDNA partial sequencing; most of them belong to the genera Bacillus, Cellulomonas and Cellulosimicrobium. CONCLUSIONS: This novel approach provides unique and valuable information for direct primary screening when the target of selection is micro-organisms exhibiting protein-degrading activity, polysaccharide-degrading activity or a specific combination of them. SIGNIFICANCE AND IMPACT OF THE STUDY: This plate assay is convenient and easy to perform, rapid, and more adaptable for screening of a large number of samples, compared with other existing methods in the literature. 相似文献
26.
Roel W. Ten Broek Sander Grefte Johannes W. Von den Hoff 《Journal of cellular physiology》2010,224(1):7-16
Skeletal muscle regeneration is a complex process, which is not yet completely understood. Satellite cells, the skeletal muscle stem cells, become activated after trauma, proliferate, and migrate to the site of injury. Depending on the severity of the myotrauma, activated satellite cells form new multinucleated myofibers or fuse to damaged myofibers. The specific microenvironment of the satellite cells, the niche, controls their behavior. The niche contains several components that maintain satellite cells quiescence until they are activated. In addition, a great diversity of stimulatory and inhibitory growth factors such as IGF‐1 and TGF‐β1 regulate their activity. Donor‐derived satellite cells are able to improve muscle regeneration, but their migration through the muscle tissue and across endothelial layers is limited. Less than 1% of their progeny, the myoblasts, survive the first days upon intra‐muscular injection. However, a range of other multipotent muscle‐ and non‐muscle‐derived stem cells are involved in skeletal muscle regeneration. These stem cells can occupy the satellite cell niche and show great potential for the treatment of skeletal muscle injuries and diseases. The aim of this review is to discuss the niche factors, growth factors, and other stem cells, which are involved in skeletal muscle regeneration. Knowledge about the factors regulating satellite cell activity and skeletal muscle regeneration can be used to improve the treatment of muscle injuries and diseases. J. Cell. Physiol. 224:7–16, 2010 © 2010 Wiley‐Liss, Inc. 相似文献
27.
It was shown that bidistilled modified water induces a marked decrease in the intensity of intrinsic fluorescence of bovine serum albumin and increases the binding of this protein to the fluorescent probe 1.8 ANS. These effects can be interpreted as a denaturing action of bidistilled modified water on the protein and a change in its conformational state, which is probably caused by changes in the microenvironment of the protein molecule. In addition, a substantial increase in the intrinsic fluorescence of bidistilled modified water, as compared with that of distilled water, was found. 相似文献
28.
When two binary responses are measured for each study subject across time, it may be of interest to model how the bivariate associations and marginal univariate risks involving the two responses change across time. To achieve such a goal, marginal models with bivariate log odds ratio and univariate logit components are extended to include random effects for all components. Specifically, separate normal random effects are specified on the log odds ratio scale for bivariate responses and on the logit scale for univariate responses. Assuming conditional independence given the random effects facilitates the modeling of bivariate associations across time with missing at random incomplete data. We fit the model to a dataset for which such structures are feasible: a longitudinal randomized trial of a cardiovascular educational program where the responses of interest are change in hypertension and hypercholestemia status. The proposed model is compared to a naive bivariate model that assumes independence between time points and univariate mixed effects logit models. 相似文献
29.
We extend an approach for estimating random effects parameters under a random intercept and slope logistic regression model to include standard errors, thereby including confidence intervals. The procedure entails numerical integration to yield posterior empirical Bayes (EB) estimates of random effects parameters and their corresponding posterior standard errors. We incorporate an adjustment of the standard error due to Kass and Steffey (KS; 1989, Journal of the American Statistical Association 84, 717-726) to account for the variability in estimating the variance component of the random effects distribution. In assessing health care providers with respect to adult pneumonia mortality, comparisons are made with the penalized quasi-likelihood (PQL) approximation approach of Breslow and Clayton (1993, Journal of the American Statistical Association 88, 9-25) and a Bayesian approach. To make comparisons with an EB method previously reported in the literature, we apply these approaches to crossover trials data previously analyzed with the estimating equations EB approach of Waclawiw and Liang (1994, Statistics in Medicine 13, 541-551). We also perform simulations to compare the proposed KS and PQL approaches. These two approaches lead to EB estimates of random effects parameters with similar asymptotic bias. However, for many clusters with small cluster size, the proposed KS approach does better than the PQL procedures in terms of coverage of nominal 95% confidence intervals for random effects estimates. For large cluster sizes and a few clusters, the PQL approach performs better than the KS adjustment. These simulation results agree somewhat with those of the data analyses. 相似文献
30.
Ten Hagen KG Tran DT Gerken TA Stein DS Zhang Z 《The Journal of biological chemistry》2003,278(37):35039-35048
Here we report the cloning and functional characterization of eight members of the UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase gene family from Drosophila melanogaster (polypeptide GalNAc transferase = pgant1-8). Full-length cDNAs were isolated from a Drosophila embryonic library based on homology to known ppGaNTases. Alignments with characterized mammalian isoforms revealed strong sequence similarities between certain fly and mammalian isoforms, highlighting putative orthologues between the species. In vitro activity assays demonstrated biochemical transferase activity for each gene, with three isoforms requiring glycosylated substrates. Comparison of the activities of Drosophila and mammalian orthologues revealed conservation of substrate preferences against a panel of peptide and glycopeptide substrates. Furthermore, Edman degradation analysis demonstrated that preferred sites of GalNac addition were also conserved between certain fly and mammalian orthologues. Semi-quantitative PCR amplification of Drosophila cDNA revealed expression of most isoforms at each developmental stage, with some isoforms being less abundant at certain stages relative to others. In situ hybridization to Drosophila embryos revealed specific staining of pgant5 and pgant6 in the salivary glands and pgant5 in the developing hindgut. Additionally, pgant5 and pgant6 expression within the egg chamber was restricted to the follicle cells, cells known to be involved in egg formation and subsequent embryonic patterning. The characterization reported here provides additional insight into the use of this model system to dissect the biological role of this enzyme family in vivo during both fly and mammalian development. 相似文献