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31.
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The interaction of tracheal cilia with the biphasic mucus layer covering the surface of the mammalian respiratory tract may be influenced by many cell surface coat components including those having an overall negative charge. In order to assess the distribution of ciliary anionic sites, cationized ferritin (CF) was used to label the surface of rat tracheal epithelium. If pieces of trachea were fixed with 3% glutaraldehyde and treated with CF at low (L) (0.08 mg/ml), medium (M) (0.32 mg/ml PBS), or high (H) (0.64 mg/ml PBS) concentrations, the label was distributed evenly over the entire external surface of the ciliary membrane at all concentrations. Unfixed tracheal tissue was also treated with L, M, and H CF for 1 or 5 min at 4 degrees C in order to minimize lateral redistribution of CF receptors. To ensure accessibility of the cell surface to CF the samples were agitated thoroughly during exposure. Exposure for 1 min to L, M, and H CF resulted in a light binding of ferritin particles on all portions of the ciliary membrane with occasional areas of multilayered binding distributed randomly on the ciliary shaft. When unfixed trachea was treated with CF for 5 min at 4 degrees C, CF binding was similar except heavier and more uniform. In no instance was there any preferential binding of CF to the ciliary tips at any of the concentrations used. Moreover, as indicated by the CF binding pattern at L concentrations, high density negative charges are present over almost the entire surface of the cilium. These results suggest that, unlike the ciliary membrane of other organs such as oviduct, negatively charged cell surface coat molecules are present on all areas of the ciliary membrane of rat tracheal epithelia. 相似文献
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T A Reinhardt J L Napoli B Praminik E T Littledike D C Beitz J J Partridge M R Uskokovi? R L Horst 《Biochemistry》1981,20(21):6230-6235
A new metabolite of vitamin D3 has been isolated from the plasma of vitamin D3 treated cows and has been generated from 25(S),26-dihydroxyvitamin D3 with homogenates of vitamin D deficient chick kidney. This metabolite has been identified as 1,25,26-trihydroxyvitamin D3 by comigration with synthetic 1,25(S),26-trihydroxyvitamin D3 in four chromatographic systems, ultraviolet spectroscopy, mass spectrometry, and high-pressure liquid chromatography and mass spectrometry of derivatives. 1,25(S),26-Trihydroxyvitamin D3 is one-tenth as effective as 1,25-dihydroxyvitamin D3 in binding to the chick intestinal cytosol 1,25-dihydroxyvitamin D receptor. Either 25(S),26-dihydroxyvitamin D3 or 1,25-dihydroxyvitamin D3 can serve as precursor for in vitro production of 1,25,26-trihydroxyvitamin D3 by chick kidney tissue. 相似文献
34.
D J Etherington P B Newman R H Dainty S M Partridge 《Biochimica et biophysica acta》1976,445(3):739-752
Four extracellular proteolytic enzymes (I-IV) (EC 3.4.22.-) were identified in static cultures of Chromobacterium lividum (NCIB 10926) by agar gel electrophoresis and isoelectric focusing. Proteinases I-III were freed of non-enzymic protein by chromatography on TEAE-cellulose and CM-cellulose. The enzyme mixture was then fractionated in a pH gradient by isoelectric focusing. All three enzymes were shown to be heat-labile metallo-enzymes. Optimal activity occurred at pH 5.6 for enzyme I and at pH 6.2 for enzymes II and III. Remazolbrilliant Blue-hide powder was a sensitive substrate for these enzymes. Proteinase I was also shown to degrade haemoglobin and casein effectively, but not myoglobin, ovalbumin or bovine serum albumin. Proteinases I-III exhibited molecular weight values of 75 000, 72 000 and 67 000 by exclusion chromatography and 71 000 and 66 000 by sodium dodecyl sulphate-poly-acrylamide-gel electrophoresis for enzyme I and II, respectively. The amino acid compositions of enzymes I and II were somewhat similar. Proteinase I was inhibited by EDTA, 1,2-di(2-aminoethoxy)ethane-N,N,N',N'-tetraacetic activity. Mg2+ could substitute for Ca2+ or Mn2+ for Co2+. The interrelationship of proteinases I-III is discussed. 相似文献
35.
Chondroitin sulfate-protein of bovine cartilage 总被引:2,自引:0,他引:2
S M Partridge 《Federation proceedings》1966,25(3):994-996
36.
Surfactant protein-A (SP-A) belongs to a family of collagen-containing C-type lectins called collectins. SP-A is expressed by renal tubule epithelial cells. We investigated the distribution of SP-A in renal cell carcinomas (RCC) using immunohistochemical techniques and western blotting. We used 35 formalin fixed, paraffin embedded (FFPE) RCC tissue samples. We compared results with clinico-pathological parameters of RCC including age, sex, Fuhrman grade, tumor volume, tumor node metastasis (TNM) and clinical stage. SP-A was localized in the glomerulus and renal tubule epithelium in nontumor tissue and strong SP-A immunoreactivity was observed in tumor tissue. SP-A was expressed in the RCC tumor cells (64%) and nontumor cells (34%) in males and RCC tumor cells (90%) and nontumor cells (30%) in females. There was a significant correlation between SP-A immunoreactivity in tumor cells and gender, age, tumor diameter, Fuhrman grade and tumor diameter. Western blot analysis supported the immunohistochemical findings. We present evidence for involvement of SP-A in RCC and suggest that increased SP-A expression in RCC is associated with favorable prognosis. 相似文献
37.
C Rodríguez-Burford D K Oelschlager L I Talley M N Barnes E E Partridge 《Biotechnic & histochemistry》2013,88(1):17-21
We describe here a computational morphology-based approach to the investigation of possible causes of chromatin alterations in sperm. A comprehensive set of state-of-the-art and geometric measures are computationally extracted from toluidine blue stained images and analyzed to infer the possible processes leading to normal and abnormal chromatin formation while seeking a possible taxonomy of chromatin alterations and their influence on sperm head morphology. Using this methodology, we have identified higher chromatin fragility at some specific points of the sperm head. Despite the lack of correlation between morphologies of sperm head and chromatin structure, four main morphological types of chromatin alterations in bull spermatozoa have been identified and their possible causes discussed. 相似文献
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In a three-hour bioassay, we tested the palatability and feeding preferences of Uresiphita maorialis (kōwhai moth) for Sophora tetraptera, Sophora microphylla and Sophora prostrata. Palatability tests showed no differences among the Sophora species. Feeding preferences, on the other hand, showed that S. tetraptera and S. microphylla leaves are preferred over S. prostrata leaves. Our results support our field observations in Wellington city parks and gardens showing that S. tetraptera and S. microphylla plants frequently have higher densities of larvae than S. prostrata. 相似文献