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541.
Submucosal Gland Myoepithelial Cells Are Reserve Stem Cells That Can Regenerate Mouse Tracheal Epithelium 总被引:1,自引:0,他引:1
Thomas J. Lynch Preston J. Anderson Pavana G. Rotti Scott R. Tyler Adrianne K. Crooke Soon H. Choi Daniel T. Montoro Carolyn L. Silverman Weam Shahin Rui Zhao Chandler W. Jensen-Cody Andrea Adamcakova-Dodd T. Idil Apak Evans Weiliang Xie Yulong Zhang Hongmei Mou B. Paul Herring Peter S. Thorne John F. Engelhardt 《Cell Stem Cell》2018,22(5):653-667.e5
542.
Abstract The palatability to common carp, Cyprinus carpio L. of three newly developed differently flavoured floating pellets made from a high proportion (40%) of brewer's spent grain (BSG) was tested using a multiple-offer feeding experiment. The addition of ‘bold’ flavours, such as vanilla or strawberry essence, may help mask the unpleasant taste of some piscicides; however, their inclusion must not compromise uptake by carp. There were no significant differences between the consumption rates of the three varieties, and all flavours were readily consumed. Therefore, it is suggested that highly flavoured pellets made with BSG have a strong potential to mask the flavour of an unpalatable toxin, and further research is now needed to test this hypothesis. 相似文献
543.
Kathryn E. Muratore Barbara E. Engelhardt John R. Srouji Michael I. Jordan Steven E. Brenner Jack F. Kirsch 《Proteins》2013,81(9):1593-1609
The subfamily Iα aminotransferases are typically categorized as having narrow specificity toward carboxylic amino acids (AATases), or broad specificity that includes aromatic amino acid substrates (TATases). Because of their general role in central metabolism and, more specifically, their association with liver‐related diseases in humans, this subfamily is biologically interesting. The substrate specificities for only a few members of this subfamily have been reported, and the reliable prediction of substrate specificity from protein sequence has remained elusive. In this study, a diverse set of aminotransferases was chosen for characterization based on a scoring system that measures the sequence divergence of the active site. The enzymes that were experimentally characterized include both narrow‐specificity AATases and broad‐specificity TATases, as well as AATases with broader‐specificity and TATases with narrower‐specificity than the previously known family members. Molecular function and phylogenetic analyses underscored the complexity of this family's evolution as the TATase function does not follow a single evolutionary thread, but rather appears independently multiple times during the evolution of the subfamily. The additional functional characterizations described in this article, alongside a detailed sequence and phylogenetic analysis, provide some novel clues to understanding the evolutionary mechanisms at work in this family. Proteins 2013. © 2013 Wiley Periodicals, Inc. 相似文献
544.
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546.
von Bülow V Dubben S Engelhardt G Hebel S Plümäkers B Heine H Rink L Haase H 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(6):4180-4186
547.
Choreography for nucleosomes: the conformational freedom of the nucleosomal filament and its limitations 总被引:1,自引:0,他引:1
Engelhardt M 《Nucleic acids research》2007,35(16):e106
Eukaryotic DNA is organized into nucleosomes by coiling around core particles of histones, forming a nucleosomal filament. The significance for the conformation of the filament of the DNA entry/exit angle (α) at the nucleosome, the angle of rotation (β) of nucleosomes around their interconnecting DNA (linker DNA) and the length of the linker DNA, has been studied by means of wire models with straight linkers. It is shown that variations in α and β endow the filament with an outstanding conformational freedom when α is increased beyond 60–90°, owing to the ability of the filament to change between forward right-handed and backward left-handed coiling. A wealth of different helical and looped conformations are formed in response to repeated β sequences, and helical conformations are shown to be able to contract to a high density and to associate pairwise into different types of double fibers. Filaments with random β sequences are characterized by relatively stable loop clusters connected by segments of higher flexibility. Displacement of core particles along the DNA in such fibers, combined with limited twisting of the linkers, can generate the β sequence necessary for compaction into a regular helix, thus providing a model for heterochromatinization. 相似文献
548.
Aggregations of juvenile whale sharks (<Emphasis Type="Italic">Rhincodon typus</Emphasis>) in the Gulf of Tadjoura,Djibouti 总被引:1,自引:0,他引:1
D. Rowat M. G. Meekan U. Engelhardt B. Pardigon M. Vely 《Environmental Biology of Fishes》2007,80(4):465-472
A total of 23 whale sharks were identified over a 5 d period in the Arta Bay region of the Gulf of Tadjora, Djibouti. Most
of the sharks aggregating in this area were small (<4 m TL) males. Individuals were identified using photographs of distinctive
scars and spot and stripe patterns on the sides of the animals. Of these, 65% had scarring that was attributable to boat or
propeller strikes. Most of the whale sharks we encountered were feeding on dense accumulations of plankton in shallow water
just off (10–200 m) the shoreline. This food source may account for the aggregation of sharks in this area. One 3 m male shark
was tagged with an ARGOS (Splash) satellite tag for 9 d. During this time the shark traversed to the shoreline on the opposite
side of the Gulf (a distance of 14 km) and then returned to the Arta Bay area before retracing his path to the other shore.
The shark spent most of the daylight hours at the surface, while at night dives were more frequent, deeper and for longer
durations.
相似文献
D. RowatEmail: |
549.
Kavish J Bhansing Martin Lammens Hanneke KA Knaapen Piet LCM van Riel Baziel GM van Engelen Madelon C Vonk 《Arthritis research & therapy》2014,16(3):R111
Introduction
The objective was to characterize the clinical and myopathologic features of patients with scleroderma-polymyositis (SSc-PM) overlap compared with a population of patients with systemic sclerosis (SSc) and polymyositis (PM).Methods
A three-way comparison of patients with SSc-PM overlap (n = 25) with patients with SSc (n = 397) and PM (n = 40) on clinical and myopathologic features and causes of death. One neuropathologist blinded for the diagnosis evaluated all recent available muscle biopsies. Biopsies were scored for presence of inflammation, necrotic muscle fibers, rimmed vacuoles, fibrosis, and immunohistochemical staining. Clinical or myopathologic characteristics were compared by using the χ2 test or one-way analysis of variance (ANOVA).Results
The prevalence of SSc-PM overlap in the Nijmegen Systemic Sclerosis cohort was 5.9%. The mortality was 32% (eight of 25) in SSc-PM, of which half was related to cardiac diseases. The prevalence of pulmonary fibrosis was significantly increased in SSc-PM (83%) (P = 0.04) compared with SSc (49%) and PM (53%). SSc or myositis-specific antibodies were nearly absent in the SSc-PM group. In almost all biopsies (96%) of SSc-PM patients, necrotic muscle fibers were present, which was significantly increased compared with PM patients (P = 0.02).Conclusions
Patients with SSc-PM have increased prevalence of pulmonary fibrosis and cardiac disease as the cause of death compared with patients with SSc and PM . In addition, we found that necrotizing muscle fibers with inflammation characterize SSc-PM overlap in muscle biopsies. Further research should focus on underlying mechanisms causing necrosis, inflammation, and fibrosis and their relation to pulmonary involvement and mortality in patients with SSc-PM overlap. 相似文献550.
Michael Behr Johanna K. Kaufmann Patrick Ketzer Sarah Engelhardt Martin Mück-H?usl Pamela M. Okun Gabriele Petersen Frank Neipel Jessica C. Hassel Anja Ehrhardt Alexander H. Enk Dirk M. Nettelbeck 《PloS one》2014,9(4)
Adenoviral gene therapy and oncolysis would critically benefit from targeted cell entry by genetically modified capsids. This requires both the ablation of native adenovirus tropism and the identification of ligands that remain functional in virus context. Here, we establish cell type-specific entry of HAdV-5-based vectors by genetic ligand insertion into a chimeric fiber with shaft and knob domains of the short HAdV-41 fiber (Ad5T/41sSK). This fiber format was reported to ablate transduction in vitro and biodistribution to the liver in vivo. We show that the YSA peptide, binding to the pan-cancer marker EphA2, can be inserted into three positions of the chimeric fiber, resulting in strong transduction of EphA2-positive but not EphA2-negative cells of human melanoma biopsies and of tumor xenografts after intratumoral injection. Transduction was blocked by soluble YSA peptide and restored for EphA2-negative cells after recombinant EphA2 expression. The YSA peptide could also be inserted into three positions of a CAR binding-ablated HAdV-5 fiber enabling specific transduction; however, the Ad5T/41sSK format was superior in vivo. In conclusion, we establish an adenovirus capsid facilitating functional insertion of targeting peptides and a novel adenovirus using the tumor marker EphA2 as receptor with high potential for cancer gene therapy and viral oncolysis. 相似文献