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Tandler Bernard Denning Carolyn R. Mandel Irwin D. Kutscher Austin H. 《Cell and tissue research》1969,94(4):555-564
Summary Human labial salivary glands, obtained by biopsy from 32 subjects, were studied by light and electron microscopy. Intranuclear inclusions, unrelated to nucleoli, were present in many of the acinar nuclei in glands from 16 of the 32 donors. More than one inclusion was sometimes observed within a single nucleus. They measured about 1 in diameter, and were stainable in a variety of ways. They were eosinophilic, some were stained by Nile blue sulphate, some were PAS-positive, and all were Feulgen-negative. They were bounded by a single membrane, which never exhibited continuity with the nuclear envelope, and they showed considerable morphological variation. The more complex inclusions consisted of alternating shells of light and dark material with tiny dense granules embedded in the latter. The intranuclear inclusions, which apparently were non-viral in origin, were in some way related to the secretory cycle of the mucous cells, since they were found only in immature cells, and never in cells in which secretory products were abundant.This work was supported in part by grants from the Henry Spenadel Trust and the Max C. Fleischmann Foundation of Nevada, by grant CA-08748 from the National Cancer Institute, by grant 5 SO1 FR 05335-07 from the National Institutes of Health, by a grant from the National Cystic Fibrosis Research Foundation, and by an Institutional Grant to the School of Dental and Oral Surgery, Columbia University, from the National Institutes of Health.The authors are indebted to Dr.Louis Mandel for performing the biopsies used in this study. The expert technical assistance of Mrs.Mona Seggio is acknowledged. 相似文献
73.
Synaptosomal protein synthesis in a cell-free system 总被引:11,自引:4,他引:7
—Synaptosomes were isolated from cerebral cortex of young rats and incubated with 14C-labelled l -leucine in vitro. Amino acid incorporation into proteins of the synaptosomal cytoplasm, mitochondria and membrane components was observed. There was no incorporation into proteins of the vesicles. The protein-synthesizing system was not stimulated by the addition of either ATP or an ATP-generating system. ATP at all concentrations was inhibitory. Two different protein-synthesizing systems operate in the synaptosome. One, sensitive to inhibition by chloramphenicol and related antibiotics, is found in the mitochondrial subfraction and the other, inhibited by cycloheximide, is located either in the membrane components or the synaptosomal cytoplasm. This second system resembles the eukaryotic ribosomal system in its sensitivity to cycloheximide. Both the synaptosomal soluble fraction and the synaptosomal membrane fractions were shown previously to contain RNA. This RNA could function in protein-synthesizing mechanisms in the synaptosome. These results deomonstrate that protein is synthesized in axonal components and show that it is unnecessary to postulate that all axonal protein is supplied by somato-axonal flow. 相似文献
74.
Characterisation of amino acid incorporation by subcellular fractions from sterile beet disks 总被引:1,自引:1,他引:0
Summary The optimum concentrations of leucine, ATP, GTP and Mg2+ ion for the incorporation of leucine into protein by the microsomal fraction isolated from sterile disks of red beetroot are 0.06 mM, 5 mM, 0.5 mM, and 12 mM respectively. Incorporated 14C-leucine does not exchange with an excess of soluble-12C-leucine. Incorporation into protein is partly dependent on the addition of a high speed supernatant fraction which incorporates leucine into a product with the properties of aminoacyl RNA. Addition of polyuridylic acid to microsomes isolated from fresh disks stimulates the incorporation of phenylalanine into protein nine-fold but has no effect on leucine incorporation. Polyuridylic acid — stimulated incorporation is not inhibited by chloramphenicol. Preincubation of fresh microsomes with trypsin does not increase their activity. These results suggest that the low activity of fresh microsomes may be due to a lack of messenger RNA. The mitochondrial fraction shows a rise and fall in leucine-incorporating ability during aging similar to that shown by the microsomal fraction. Studies with inhibitors suggest that about 25% of this incorporation is due to the mitochondria themselves, the rest being attributable to large microsomes. Fractions isolated from disks aged under non-sterile conditions show large incorporations of leucine which are not dependent on an added energy source. This result confirms the importance of using aseptic techniques when studying the aging of storage tissue disks. 相似文献
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