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991.
K Ishimura T Yoshinaga-Hirabayashi H Fujita H Ishii-Ohba H Inano B Tamaoki 《Histochemistry》1988,89(1):35-39
The localization of 3 beta-hydroxysteroid dehydrogenase/isomerase (3 beta-HSD) was studied in bovine adrenal glands by light as well as electron microscopic immunocytochemistry, using anti-bovine adrenal 3 beta-HSD antibody. With light microscopy the cytoplasm of the glomerulosa cells was weakly immunostained, while that of the fasciculata-reticularis cells was intensely immunostained though both the capsular connective tissue cells and the medullary cells were entirely negative for this reaction. Electron microscopic immunocytochemistry revealed that the positive reaction products for 3 beta-HSD were present on the membrane of smooth endoplasmic reticulum of the cortical cells, especially that of the fasciculata and reticularis cells. Other cell organelles such as mitochondria and Golgi apparatus were entirely negative. The present results indicate that 3 beta-HSD is present in the membrane of smooth endoplasmic reticulum of bovine adrenal cortical cells. 相似文献
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995.
K Yamasaki G Kawai Y Ito Y Muto J Fujita T Miyazawa S Nishimura S Yokoyama 《Biochemical and biophysical research communications》1989,162(3):1054-1062
The conformations of a truncated human c-Ha-ras gene product [ras(1-171) protein] in the GDP-bound form and in the GTP gamma S-bound form were compared by two-dimensional nuclear Overhauser effect spectroscopy (NOESY). As for the GDP-bound ras(1-171) protein, three NOESY cross peaks were observed in the region of 4.5-6.0 ppm, indicating a regular antiparallel beta-sheet structure. On the ligand exchange from GDP to GTP gamma S, one of the three NOESY cross peaks disappeared and the other two cross peaks were appreciably shifted. By analysis of the effects of specific deuteration of leucine residues and the homonuclear Hartmann-Hahn spectroscopy, the antiparallel beta-sheet was found to consist of residues 38-44 and residues 51-57. The conformations around Ser-39 and Leu-56 are of the regular antiparallel beta-strand type in the GDP-bound state, and largely distorted in the GTP gamma S-bound state, which is probably related to the conformational activation of the effector region of ras proteins by ligand exchange from GDP to GTP gamma S. 相似文献
996.
Epidermal growth factor (EGF) has been first isolated from the submandibular glands of the male mouse and recently from human urine. Despite its potent mitogenic effect in a variety of tissues, the physiological functions of EGF in human still remain undetermined. In order to study the effect of age on urinary human EGF (hEGF), we have evaluated urinary excretion of hEGF in normal subjects over a wide range of age (20–79 yr.) using homologous radioimmunoassay (RIA) for hEGF. Urinary excretion of hEGF expressed as a function of creatinine significantly decreased with increasing age, age, while females excreted significantly more hEGF than males. These data suggest that urinary excretion of hEGF decreases with age in normal subjects which may be due to reduced synthesis and/or secretion of hEGF. 相似文献
997.
Yosuke Nakatani Yoshito Kakihara Shiho Shimizu Masayuki Kurose Tsutomu Sato Mitsuoki Kaneoke 《Bioscience, biotechnology, and biochemistry》2019,83(1):155-165
We determined if Japanese Rice Wine (Sake) had inhibitory effects on stress-induced enhancement of masseter muscle (MM) nociception in the rats. Male rats were subjected to the repeated forced swim stress (FS) or sham conditionings from Day ?3 to ?1. Daily administration of Sake or saline was conducted after each stress conditioning. At Day 0 the number of Fos positive cells, a marker for neural activity, was quantified at the trigeminal subnucleus caudalis (Vc) region by MM injury with formalin. FS increased MM-evoked Fos expression in the Vc region, which was inhibited by Sake compared to saline administration. Sake did not alter the number of Fos positive cells under sham conditions, indicating that inhibitory roles of Sake on neural activity in the Vc region were seen under FS conditions. These findings indicated that Sake had inhibitory roles on stress-induced MM nociception at the Vc region in our experimental conditions. 相似文献
998.
Fujita Y Hayashi T Kiyomitsu T Toyoda Y Kokubu A Obuse C Yanagida M 《Developmental cell》2007,12(1):17-30
The centromere is the chromosomal site that joins to microtubules during mitosis for proper segregation. Determining the location of a centromere-specific histone H3 called CENP-A at the centromere is vital for understanding centromere structure and function. Here, we report the identification of three human proteins essential for centromere/kinetochore structure and function, hMis18alpha, hMis18beta, and M18BP1, the complex of which is accumulated specifically at the telophase-G1 centromere. We provide evidence that such centromeric localization of hMis18 is essential for the subsequent recruitment of de novo-synthesized CENP-A. If any of the three is knocked down by RNAi, centromere recruitment of newly synthesized CENP-A is rapidly abolished, followed by defects such as misaligned chromosomes, anaphase missegregation, and interphase micronuclei. Tricostatin A, an inhibitor to histone deacetylase, suppresses the loss of CENP-A recruitment to centromeres in hMis18alpha RNAi cells. Telophase centromere chromatin may be primed or licensed by the hMis18 complex and RbAp46/48 to recruit CENP-A through regulating the acetylation status in the centromere. 相似文献
999.
Many higher plants contain novel metabolites with antimicrobial, antifungal and antiviral properties. However, in the developed world almost all clinically used chemotherapeutics have been produced by in vitro chemical synthesis. Exceptions, like taxol and vincristine, were structurally complex metabolites that were difficult to synthesize in vitro. Many non-natural, synthetic drugs cause severe side effects that were not acceptable except as treatments of last resort for terminal diseases such as cancer. The metabolites discovered in medicinal plants may avoid the side effect of synthetic drugs, because they must accumulate within living cells. The aim here was to test an aqueous extract from the young developing leaves of willow (Salix safsaf, Salicaceae) trees for activity against human carcinoma cells in vivo and in vitro. In vivo Ehrlich Ascites Carcinoma Cells (EACC) were injected into the intraperitoneal cavity of mice. The willow extract was fed via stomach tube. The (EACC) derived tumor growth was reduced by the willow extract and death was delayed (for 35 days). In vitro the willow extract could kill the majority (75%-80%) of abnormal cells among primary cells harvested from seven patients with acute lymphoblastic leukemia (ALL) and 13 with AML (acute myeloid leukemia). DNA fragmentation patterns within treated cells inferred targeted cell death by apoptosis had occurred. The metabolites within the willow extract may act as tumor inhibitors that promote apoptosis, cause DNA damage, and affect cell membranes and/or denature proteins. 相似文献
1000.