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81.
82.
Induction of aldose reductase expression in rat kidney mesangial cells and Chinese hamster ovary cells under hypertonic conditions 总被引:4,自引:0,他引:4
M Kaneko D Carper C Nishimura J Millen M Bock T C Hohman 《Experimental cell research》1990,188(1):135-140
Rat kidney cortex mesangial cells (MES) and Chinese hamster ovary cells (CHO) responded to hypertonicity (600 mosmol/kg) in culture by accumulating sorbitol. The accumulation of sorbitol was due to increased aldose reductase (AR) activity, apparently brought about by increased levels of AR mRNA and protein. The levels of AR mRNA increased approximately 60-fold in MES cells and 30-fold in CHO cells by 24 h in culture media (300 mosmol/kg supplemented with 150 mM NaCl, 600 mosmol/kg total). AR activity also markedly increased (14- to 16-fold above control), but MES took 4 days and CHO 6 days to reach this maximum. Other osmolytes, raffinose and sorbitol (at concentrations of 250 to 300 mM) elicited the same response as that of 150 mM NaCl. These data show that AR expression is induced in MES and CHO cells under hypertonic conditions. Of special interest is the induction of large amounts of AR in rat kidney cortex mesangial cells, a target tissue of diabetes and a site where excessive accumulation of sorbitol is suspected to be a critical factor in diabetic nephropathy. 相似文献
83.
84.
Two new non-protein amino acids, Nδ-benzoyl-l-ornithine and Nδ-benzoyl-l-γ-hydroxyornithine have been characterized from the seeds of Vicia pseudo-orobus. 相似文献
85.
86.
Professor Shoji Matsushima Yuko Morisawa Larry J. Petterborg Jeannette W. Zeagler Russel J. Reiter 《Cell and tissue research》1979,204(3):407-416
Summary Fine structural features of pinealocytes of cotton rats (Sigmodon hispidus) were examined. Golgi complexes, mitochondria, endoplasmic reticulum and polysomes are usual organelles seen in the perikaryonal cytoplasm of pinealocytes. Many non-granulated vesicles (40 to 80 nm in diameter) and a few granulated vesicles (about 100 nm in diameter) are associated with the Golgi cisternae. Occasionally, the cisternae contain granular materials. The perikaryonal cytoplasm of pinealocytes is characterized by the presence of inclusion bodies. These bodies are usually round in shape, not bounded by a limiting membrane and composed of fine granular or filamentous materials of high electron-opacity, which are similar in appearance to the substance seen in the nucleolonema. Pinealocyte processes, filled with abundant non-granulated vesicles and some granulated vesicles, are mainly found within the parenchyma and occasionally in perivascular spaces.Supported in part by NSF grant no. PCM 77-05734 and NIH grant no. HD-10202 (Morphology Core) 相似文献
87.
88.
A male infant with monosomy 21. 总被引:2,自引:0,他引:2
A male infant with total monosomy 21 identified by Q-, G- and R-banding is described. His main symptoms are hypertonia, micrognathia, microphthalmus, imperforate anus, ambiguous external genitalia, floating and malopposed thumbs, overlying fingers, right clubfoot and growth retardation. Both parents are phenotypically as well as karotypically normal. 相似文献
89.
Vibrio parahaemolyticus was observed to adsorb onto chitin particles and copepods. The efficiency of adsorption was found to be dependent on pH and on the concentration of NaC1 and other ions found in seawater. Highest efficiency was observed in water samples collected from Chesapeake Bay and lowest in water from the open sea. V. parahaemolyticus was found to adborb onto chitin with the highest efficiency of the several bacterial strains tested. Escherichia coli and Pseudomonas fluorescens did not adsorb onto chitin. The adsorption effect is considered to be one of the major factors determining the distribution of this species and affecting the annual cycle of V. parahaemolyticus in the estuarine system. 相似文献
90.
Y Kaneko 《Hormones et métabolisme》1976,8(3):202-206
Thyroid cells from euthyroid patients with Graves' disease were cultured in a chemically defined medium. The cells preserved the ability to respond to TSH with 8-fold increase in cyclic AMP concentration. This cyclic AMP response to TSH was diminished by prior exposure of cells to TSH. The decrease in cyclic AMP response to TSH induced to TSH was reversible, was not associated with a similar decrease to cyclic AMP response to PGE1, and could not be attributed to increased phosphodiesterase activity or to decreased adenyl cyclase activity. The partial resistence to TSH stimulation of thyroid cells previously exposed to TSH may be due to changes in the TSH receptor, possibly caused by TSH itself. 相似文献