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- ItemEmbargoPDGF Signaling in Sertoli Cell Cilia and Seminiferous Tubule Morphogenesis(0023-07) Ahmadi Jeyhoonabadi, Maryam; Dobrinski, Ina; Gilch, Sabine; Jiami GuoImmature porcine testicular Sertoli cells possess primary cilia, organelles that transmit extracellular signals into the cell. A yet unidentified ciliary signal in Sertoli cells has been found necessary for in vitro morphogenesis of tubules and testicular organoids. Herein, we hypothesized that platelet-derived growth factor receptor alpha (PDGFRα) signaling through the cilia of the Sertoli cells modifies cell migration and extracellular matrix (ECM) production, consequently altering in vitro formation of testicular organoids and seminiferous tubules. Immunocytochemistry revealed PDGFRα was present on Sertoli cell cilia as well as the rest of the cell membrane and cytoplasm. Inhibiting PDGFRα signaling did not prevent organoid and tubule formation. However, it appeared to correlate with ablation of cytoplasmic extensions from the surface of the in vitro formed tubules. Inhibition of PDGFRα signaling resulted in reduction in cell area, increase in the percentage of cells with prominent peripheral paxillin expression, and increase in the number of ciliated cells and cilia length. Immunohistochemistry revealed that cilia, which colocalized with PDGFRα, were positioned away from the basement membrane of the seminiferous tubules, close to the Sertoli cell nuclei, in an area that was occupied with Sertoli cell cytoplasm. When observed via transmission electron microscopy, Sertoli cell cilia exhibited ciliary pockets around their axoneme. These results demonstrate that PDGFRα activity in Sertoli cells can influence in vitro tubule morphogenesis, possibly by altering cell cytoskeleton, cell-ECM interaction, and cilia. However, the role of cilia-specific signaling remains to be determined.
- ItemEmbargoA Study of extensive air showers at mountain altitude(1959) Legge, John Carlyle; Wilson, Brian G.
- ItemEmbargoObservations on extensive air showers at mountain altitude(1960) Dionne, Gilles J. G.; Wilson, Brian G.
- ItemEmbargoMeteorological effects on cosmic radiation at intermediate depths underground(1961) Jenkins, Robert W.; Terentiuk, Fred
- ItemEmbargoObservation of corpuscular streams by radio methods: preliminary theoretical survey and development of instrumentation(1962) Fulford, Dennis Rodney; Buckmaster, Harvey A.
- ItemEmbargoCosmic ray intensity increases associated with solar flares(1962) Nehra, Chandra P.; Wilson, Brian G.
- ItemEmbargoLithology and petrography of transitional Jurassic-Cretaceous clastic rocks, southern Rocky Mountains(1963) McGugan, June E. Rapson; Oliver, Thomas A.
- ItemEmbargoAn Electron microscopic study of the sub-oesophageal ganglion of the cockroach, Periplaneta Americana(1963) Emberson, John W.; Challice, Cyril E.
- ItemEmbargoWater supplies and watershed management in the Oldman River Basin, Alberta(1963) Raby, Stewart; Laycock, Arleigh H.Potential needs for suitable water supplies in the Prairie Provinces can only be met efficiently through planned water use in the Saskatchewan-Nelson River Basin and careful management of runoff on the Eastern Slopes of the Rocky Mountains. dverse features of streamflow in the Oldman River Basin of southwestern Alberta can be partially modified by effecting changes in the water balance on the area's watersheds, though a programme of preservation , restoration and intensive research must necessarily precede any attempt to do this s a necessary preliminary to this approach , the patterns of surface water resources in the basin are examined in terms of variations in the water balance from place to place . The achievements of the Eastern Rockies Forest Conservation Board are considered relative to its stated objectives, the Board's concept of multiple-use and the present condition of watersheds on the Eastern Slopes . Priorities and pre- requisites for effective implementation of those directives are then examined.
- ItemEmbargoEffects of specific solvation on kinetic activation parameters of some benzyl halides in binary solvent mixtures(1963) Wills, Ronald; Hyne, James Bisset
- ItemEmbargoA Functional comparison of the central retail district with two regional shopping centres in Calgary, Alberta(1963) Johnson, Denis Bruce; Boal, Frederick W.
- ItemEmbargoThe Glacial geomorphology of the Upper Red Deer River Valley, Alberta(1963) McPherson, Harold James; Nelson, James GordonThe major purpose of this study was to describe and interpret in terms of process the landforms created during the deglaciation of the mountainous upper Red Deer river valley. A review of the literature suggested two possible ways in which ice may have retreated during deglaciation. The ice may have retreated in a series of stillstands with recessional positions of the ice marked by end or recessional moraines and associated outwash deposits. Or alternatively, the ice may have stagnated and retreated mainly by melting and lowering in place. This latter idea, first suggested by the Scandinavian school of geomorphologists has been applied to the interpretation of the landforms of the Canadian prairies. Until the present study, however, its possible applicability to alpine landforms in Alberta had not been investigated. The procedure in this study was to map various kinds of drift in the upper Red Deer valley and to interpret the deposits from the standpoint of deglacial process. In addition, detailed studies in the Red Deer river channel were begun. Stakes were placed by plane tabling at a number of localities in the channel with a view to measuring rates of channel erosion and deposition, and the factors controlling these, over a period of several years. Observations reveal differences in the textural and structural character of the deposits, in and around the stream channel in front of the Drummond Glacier and similar deposits located farther downstream. The material close to the ice contains much more poorly sorted and stratified material. Downstream in places, wide alluvial flats occur, and these are composed predominantly of subrounded to rounded stratified and sorted gravels and fines. The presence of poorly stratified and poorly sorted material close to the ice indicates that material of outwash type is not forming in quantity in front of the ice today. This, in turn, suggests that the braided alluvial flats located farther downstream may not be outwash, when the term outwash means proglacial deposits washed out from the ice. Rather the alluvial flats located farther downstream may have been formed by fluvial erosion and deposition some time after ice retreat and some appreciable distance from the ice. Measurements of contemporary erosion and deposition on the alluvial flats, will permit estimations to be made of present day rates of change, and will serve as one kind of check on the idea of "Postglacial" creation of the flats. Mapping of surficial deposits in the valley reveal the predominance of depositional material considered to have been laid down close to melting ice. This ice proximus material gives rise to either hummocky topography or to a non-paired series of benches which parallel the river in places. Throughout the valley there exists a paucity of landforms which can be identified as recessional or end moraines, and also of outwash deposits associated with these. This, combined with the predominance of ice proximus material, indicates that the ice retreated not by a series of stillstands during deglaciation, but rather by stagnation and lowering in place.
- ItemEmbargoSpectroscopic studies of nitroso compounds and of triaryl carbonium ions(1964) Ng, Eric Kwong-Sun; Adam, Frank C.
- ItemEmbargoLacunary interpolation through trigonomicetric and power polynomials(1964) Varma, A. K.; Sharma, A.