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111.
de Wit R Hendrix CM Boonstra J Verkleu AJ Post JA 《Journal of biomolecular screening》2000,5(3):133-140
Recently, we showed that the internalization of the epidermal growth factor (EGF) receptor is inhibited by hydrogen peroxide (H(2)O(2)) in human fibroblasts. In order to test the effect of various stress conditions on receptor internalization and to test a variety of antioxidants in their capacity to prevent or reduce the H(2)O(2)-induced inhibition of internalization, a screening assay was developed to measure the internalization in 96-well plates. In this assay, cells are exposed to biotin-conjugated EGF and the amount of internalized EGF is detected with horseradish peroxidase-conjugated streptavidin. We show that the results obtained by this new assay are comparable with those from internalization studies performed with radioactive labeled EGF. Therefore, the cellular internalization assay as presented here is a reliable method to measure EGF receptor internalization. Moreover, because elaborate processing of the cells is not required, the assay is a relatively fast and inexpensive method to study ligand-induced internalization in 96-well plates and thereby is suitable for large-scale screening of compounds or conditions interfering with this internalization. 相似文献
112.
113.
Charlotte ?ngstr?m-Br?nnstr?m Gunn Engvall Tara Mullaney Kristina Nilsson Gun Wickart-Johansson Anna-Maja Sv?rd Tufve Nyholm Jack Lindh Viveca Lindh 《PloS one》2015,10(10)
Approximately 300 children, from 0 to 18 years old, are diagnosed with cancer in Sweden every year. Of these children, 80–90 of them undergo radiotherapy treatment for their cancer. Although radiotherapy is an encounter with advanced technology, few studies have investigated the child’s and the parent’s view of the procedure. As part of an ongoing multicenter study aimed to improve patient preparation and the care environment in pediatric radiotherapy, this article reports the findings from interviews with parents at baseline. The aim of the present study was twofold: to describe parents’ experience when their child undergoes radiotherapy treatment, and to report parents’ suggestions for improvements during radiotherapy for their children. Sixteen mothers and sixteen fathers of children between 2–16 years old with various cancer diagnoses were interviewed. Data were analyzed using content analysis. The findings showed that cancer and treatment turns people’s lives upside down, affecting the entire family. Further, the parents experience the child’s suffering and must cope with intense feelings. Radiotherapy treatment includes preparation by skilled and empathetic staff. The parents gradually find that they can deal with the process; and lastly, parents have suggestions for improvements during the radiotherapy treatment. An overarching theme emerged: that despair gradually turns to a sense of security, with a sustained focus on and close interaction with the child. In conclusion, an extreme burden was experienced around the start of radiotherapy, though parents gradually coped with the process. 相似文献
114.
M. C. Post R. L. Braam B. E. Groenemeijer D. Nicastia B. J. Rensing M. A. Schepens 《Netherlands heart journal》2010,18(4):209-211
A sinus of Valsalva aneurysm is a rare cardiac anomaly that may be congenital or acquired; a coexisting cardiac lesion might be present. If the aneurysm ruptures, it causes acute symptoms of dyspnoea. Echocardiography and cardiac magnetic resonance imaging are useful for diagnosis. The treatment of choice is surgery. We present a case of a patient with acute onset of symptoms due to a ruptured sinus of Valsalva aneurysm. (Neth Heart J 2010;18:209-11) 相似文献
115.
Lin YL de Villiers WJ Garvy B Post SR Nagy TR Safadi FF Faugere MC Wang G Malluche HH Williams JP 《The Journal of biological chemistry》2007,282(7):4653-4660
Class A scavenger receptor (SR-A) is predominantly expressed by macrophages, and because osteoclasts are of monocyte/macrophage lineage, SR-A is of potential interest in osteoclast biology. In addition to modified low density lipoprotein uptake, SR-A is also important in cell attachment and signaling. In this study we evaluated the effect of SR-A deletion on bone. Knock-out animals have 40% greater body weight than wild type. Body composition analyses demonstrated that total lean and fat body mass were greater in knock-out animals, but there was no significant difference in percent fat and lean body mass. Bone mineral density and content were significantly greater in knock-out compared with wild type animals. Micro-computed tomography analyses confirmed that total volume, bone volume as well as trabecular number, thickness, and connectivity were significantly greater in knock-out mice. As expected, trabecular separation was greater in wild type mice. The phenotype appears to be explained by 60% fewer osteoclasts in females and 35% fewer in males compared to wild type mice with a paradoxical increase in nuclei/osteoclast in knock-out animals. Furthermore, there were no differences in adipocyte number and osteoblast number or activity. The addition of the soluble extracellular domain of SR-A to RAW264.7 cells stimulated a concentration-dependent increase in osteoclast differentiation that was receptor activator of nuclear factor-kappaB ligand (RANKL)-dependent. Soluble SR-A had no effect on cell proliferation in the presence of RANKL but stimulated a 40% increase in numbers in the absence of RANKL. We conclude that SR-A plays a role in normal osteoclast differentiation, suggesting a novel role for this receptor in bone biology. 相似文献
116.
Climate impacts on transocean dispersal and habitat in gray whales from the Pleistocene to 2100
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S. Elizabeth Alter Matthias Meyer Klaas Post Paul Czechowski Peter Gravlund Cork Gaines Howard C. Rosenbaum Kristin Kaschner Samuel T. Turvey Johannes van der Plicht Beth Shapiro Michael Hofreiter 《Molecular ecology》2015,24(7):1510-1522
Arctic animals face dramatic habitat alteration due to ongoing climate change. Understanding how such species have responded to past glacial cycles can help us forecast their response to today's changing climate. Gray whales are among those marine species likely to be strongly affected by Arctic climate change, but a thorough analysis of past climate impacts on this species has been complicated by lack of information about an extinct population in the Atlantic. While little is known about the history of Atlantic gray whales or their relationship to the extant Pacific population, the extirpation of the Atlantic population during historical times has been attributed to whaling. We used a combination of ancient and modern DNA, radiocarbon dating and predictive habitat modelling to better understand the distribution of gray whales during the Pleistocene and Holocene. Our results reveal that dispersal between the Pacific and Atlantic was climate dependent and occurred both during the Pleistocene prior to the last glacial period and the early Holocene immediately following the opening of the Bering Strait. Genetic diversity in the Atlantic declined over an extended interval that predates the period of intensive commercial whaling, indicating this decline may have been precipitated by Holocene climate or other ecological causes. These first genetic data for Atlantic gray whales, particularly when combined with predictive habitat models for the year 2100, suggest that two recent sightings of gray whales in the Atlantic may represent the beginning of the expansion of this species' habitat beyond its currently realized range. 相似文献
117.
Jennifer M Kress-Bennett Garth D Ehrlich Ashley Bruno J Christopher Post Fen Z Hu Thomas F Scott 《BMC neurology》2011,11(1):155
Background
There are a lack of biomarkers which can be used to predict clinical outcomes for multiple sclerosis (MS) patients receiving interferon beta (IFN-β). Thus the objective of this study was to characterize changes in CD4+ T-lymphocyte expression in an unbiased manner following initiation of intramuscular (IM) IFN-β-1a treatment, and then to verify those findings using marker-specific assays. 相似文献118.
Annerieke C van Groenestijn Ingrid GL van de Port Carin D Schröder Marcel WM Post Hepke F Grupstra Esther T Kruitwagen Harmen van der Linde Reinout O van Vliet Margreet GH van de Weerd Leonard H van den Berg Eline Lindeman 《BMC neurology》2011,11(1):1-11
Background
Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.Methods
We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.Results
Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.Conclusions
The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain. 相似文献119.
Geerts WJ Vocking K Schoonen N Haarbosch L van Donselaar EG Regan-Klapisz E Post JA 《Journal of structural biology》2011,(3):350-359
Primary cilia are microtubule based sensory organelles that play an important role in maintaining cellular homeostasis. Malfunctioning results in a number of abnormalities, diseases (ciliopathies) and certain types of cancer. Morphological and biochemical knowledge on cilia/flagella, (early) ciliogenesis and intraflagellar transport is often obtained from model systems (e.g. Chlamydomonas) or from multi ciliary cells like lung or kidney epithelium.In this study endothelial cells in isolated human umbilical veins (HUVs) and cultured human umbilical vein endothelial cells (HUVECs) are compared and used to study primary ciliogenesis. By combining fluorescence microscopy, SEM, 2D and 3D TEM techniques we found that under the tested culturing conditions 60% of cobblestone endothelial cells form a primary cilium. Only a few of these cilia are present (protruding) on the endothelial cell surface, meaning that most primary cilia are in the cytoplasm (non-protruding). This was also observed in situ in the endothelial cells in the umbilical vein. The exact function(s?) of these non-protruding cilia remains unclear.Ultra-structural analysis of cultured HUVECs and the endothelial layer of the human umbilical veins reveal that there are: vesicles inside the ciliary pocket during the early stages of ciliogenesis; tubules/vesicles from the cytoplasm fuse with the ciliary sheath; irregular axoneme patterns, and two round, membranous vesicles inside the basal body.We conclude that cobblestone cultured HUVECs are comparable to the in vivo epithelial lining of the umbilical veins and therefore provide a well defined, relatively simple human model system with a reproducible number of non-protruding primary cilia for studying ciliogenesis. 相似文献
120.
Lebbad M Petersson I Karlsson L Botero-Kleiven S Andersson JO Svenungsson B Svärd SG 《PLoS neglected tropical diseases》2011,5(8):e1262