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51.
Identification of a high molecular weight nervous system specific cell surface glycoprotein on murine neuroblastoma cells 总被引:1,自引:0,他引:1
An antiserum to N18 neuroblastoma cells has been used to identify a glycoprotein of apparent molecular weight greater than 200 000 D in SDS-polyacrylamide gels. This glycoprotein (Band 1) is found in culture medium of N18 cells. An immunologically similar component can be immunoprecipitated from detergent extracts of enzymatically iodinated or biosynthetically labelled viable cells. Anti-band 1 activity can be adsorbed from the antiserum by intact N18 cells but not four other cultured murine cell lines. Normal adult murine brain also adsorbs anti-band 1 activity but adult murine adrenal, heart, kidney, liver, lung, and spleen do not. Several experiments indicate that band 1 is not myosin heavy chain or the fibroblast LETS protein. Thus band 1 is a newly identified high molecular weight nervous system specific glycoprotein. 相似文献
52.
C H Hsu T W Kurtz 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1976,151(3):475-477
Renal cortical blood flow and superficial cortical blood flow were measured in chronic sodium-loaded, sodium-deprived and normal rats. Neither total renal cortical blood flow was different among the three groups of animals. Alterations in the amount of sodium excreted, therefore, are not related to alterations of renal cortical blood flow distribution. 相似文献
53.
C W Cooper J F Obie W H Hsu 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1976,151(1):183-188
Previously we reported a homologous radioimmunoassy for rat thyrocalcitonin (TCT) which was sensitive enough (2--3 ng/ml serum) to measure TCT in thyroid venous blood or thyroid gland extracts but could not detect TCT in peripheral blood even after provocative challenge with iv calcium. In the present study chicken antisera to rat TCT were developed which were sufficiently sensitive (120--240 pg/ml serum) to permit initial evaluation of changes in TCT in rat peripheral blood. The following results were observed: (1) Basal serum TCT in young male Holtzman rats was undetectable, being less than 120--240 pg/ml; (2) induction of marked hypercalcemia by iv calcium increased TCT to approximately 1000--3000 pg/ml within 5 min; (3) thyroid cautery increased TCT to approximately 1000 pg/ml in 5--15 min; (4) calcium gavage (12.2 mg Ca/100 g) produced modest hypercalcemia in 30--60 min and increased serum TCT to approximately 500 pg/ml; (5) injection of isoproterenol raised serum TCT detectably; (6) injection of large doses of gastrin or pentagastrin did not produce detectable increases in TCT 5 or 30 min later. The results show that suitable antisera to rat TCT can be developed in chickens and applied to the measurement, by radioimmunoassay, of elevated circulating levels of TCT in the rat. 相似文献
54.
A microcolony technique has been demonstrated as being useful for the rapid determination of the viabilities of single cells of Myocbacterium fortuitum. Cultures of M. fortuitum grown to early logarithmic phase in broth were treated with the sputum digestant N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) for periods of 10 to 40 s. After growth for three generations (7.5 h) on agar films, viabilities were determined by counting under a phase contrast microscope. The viable mycobacteria grew into microcolonies that exhibited extensive branching, whereas the nonviable mycobacteria remained as single cells. Sputum was mixed with some broth cultures before treatment to stimulate the digestion process in a clinical laboratory. When broth cultures were treated with sputum digestant for 40 s, only 2.8% of the cells remained viable. When the broth cultures were mixed in a ratio of 1:4 with sputum and then treated for 40 s, 16.4% of the cells remained viable. The results also indicate M. fortuitum is very sensitive to the digestant. The results also indicate that a microcolony technique could be used for the assessment of the viability of mycobacteria. 相似文献
55.
Differential rates of sister chromatid exchanges between euchromatin and heterochromatin 总被引:1,自引:1,他引:0
In two rodent species, the Chinese hamster and the montane vole (Microtus montanus), the rate of sister chromatid exchange was lower in constitutive heterochromatin than in euchromatin. 相似文献
56.
C H Hsu T W Kurtz H G Preuss J M Weller 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1975,149(2):470-472
The radioactive microsphere technique is a simple method for measurement of RBF and intrarenal blood flow distribution in the rat that does not require surgical manipulation of the kidney or general anesthesia. The results are reproducible and compatible with other established techniques. 相似文献
57.
Po-Chih Hsu Chia-Chen Hsu Yi-Jan Hsia Chan-Yen Kuo 《Current issues in molecular biology》2022,44(4):1528
Oral cancer, a type of head and neck cancer, can pose a significant risk of death unless diagnosed and treated early. Alternative treatments are urgently needed owing to the high mortality rate, limitations of conventional treatments, and many complications. The anthraquinone compound chrysophanol acts as a tumor suppressor on some types of cancer cells. To date, it has not been clarified how chrysophanol affects human tongue squamous carcinoma. This study was aimed to examine the effects of chrysophanol on oral cancer treatment. The results show that chrysophanol caused cell death, reduced the expression of the mammalian target of rapamycin (mTOR)/peroxisome proliferator-activated receptor-alpha (PPAR-α), and increased reactive oxygen species (ROS) production. We also used two ion chelators, deferoxamine (DFO) and liproxstatin-1 (Lipro), to further determine whether chrysophanol inhibits cell growth and regulates mTOR/PPAR-α expression and ROS production, both of which are involved in iron homeostasis. The results show that DFO and Lipro reversed the increase in cell death, downregulation of mTOR/PPAR-α, and decrease in ROS accumulation. In conclusion, chrysophanol inhibits the growth of oral squamous cell carcinoma cells by modulating mTOR/PPAR-α and by causing ROS accumulation. 相似文献
58.
Shih-Ho Wang Chin-Hu Wu Chin-Chuan Tsai Tai-Yu Chen Kuen-Jang Tsai Chao-Ming Hung Chia-Yi Hsu Chia-Wei Wu Tsung-Hua Hsieh 《Current issues in molecular biology》2022,44(5):2107
Taraxacum officinale (dandelion) is often used in traditional Chinese medicine for the treatment of cancer; however, the downstream regulatory genes and signaling pathways mediating its effects on breast cancer remain unclear. The present study aimed to explore the effects of luteolin, the main biologically active compound of T. officinale, on gene expression profiles in MDA-MB-231 and MCF-7 breast cancer cells. The results revealed that luteolin effectively inhibited the proliferation and motility of the MDA-MB-231 and MCF-7 cells. The mRNA expression profiles were determined using gene expression array analysis and analyzed using a bioinformatics approach. A total of 41 differentially expressed genes (DEGs) were found in the luteolin-treated MDA-MB-231 and MCF-7 cells. A Gene Ontology analysis revealed that the DEGs, including AP2B1, APP, GPNMB and DLST, mainly functioned as oncogenes. The human protein atlas database also found that AP2B1, APP, GPNMB and DLST were highly expressed in breast cancer and that AP2B1 (cut-off value, 75%) was significantly associated with survival rate (p = 0.044). In addition, a Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the DEGs were involved in T-cell leukemia virus 1 infection and differentiation. On the whole, the findings of the present study provide a scientific basis that may be used to evaluate the potential benefits of luteolin in human breast cancer. Further studies are required, however, to fully elucidate the role of the related molecular pathways. 相似文献
59.
Involvement of Matrix Metalloproteinases on the Inhibition of Cells Invasion and Migration by Emodin in Human Neuroblastoma SH-SY5Y Cells 总被引:1,自引:0,他引:1
Hsu-Feng Lu Kuang-Chi Lai Shu-Chun Hsu Hui-Ju Lin Chao-Lin Kuo Ching-Lung Liao Jai-Sing Yang Jing-Gung Chung 《Neurochemical research》2009,34(9):1575-1583
Emodin (1,3,8-trihydroxy-6-methylanthaquinone), an active component present in the root and rhizome of Rheum palmatum L. (Polygonaceae) has anti-bacterial, anti-tumor, diuretic and vasorelaxant effects. However, its mechanism of action on
the cell migration and invasion of human neuroblastoma cancer SH-SY5Y cells is not fully understood. In this study, firstly,
the effects of emodin on the percentage of viable cells were examined by using MTT assay and it was found that emodin induced
dose-and time-dependent inhibition in human neuroblastoma SH-SY5Y cells. Second, the effects of emodin on the migration and
invasion of SH-SY5Y cells were examined by using wound assay and matrigel counting and the results showed that emodin suppressed
the migration and invasion of SH-SY5Y cells. Third, we examined the effect of emodin on the levels of associated proteins
by using Western blotting and the results indicated that emodin inhibited the levels of GRB2, RhoA, HIF-1α, VEGF, FAK, iNOS,
COX2, p-p38, p-c-jun, MMP2, MMP9 and MMP7 but promoted the levels of PKC, PI3K, MEKK3 and NF-κB p65 that led to the inhibition
of migration and invasion of SH-SY5Y cells in vitro. 相似文献
60.
Y.‐H. Hsu M. J. P. Simons J. Schroeder A. Girndt I. S. Winney T. Burke S. Nakagawa 《Journal of evolutionary biology》2017,30(5):951-959
Reproductive success is associated with age in many taxa, increasing in early life followed by reproductive senescence. In socially monogamous but genetically polygamous species, this generates the interesting possibility of differential trajectories of within‐pair and extra‐pair siring success with age in males. We investigate these relationships simultaneously using within‐individual analyses with 13 years of data from an insular house sparrow (Passer domesticus) population. As expected, we found that both within‐ and extra‐pair paternity success increased with age, followed by a senescence‐like decline. However, the age trajectories of within‐ and extra‐pair paternity successes differed significantly, with the extra‐pair paternity success increasing faster, although not significantly, in early life, and showing a delayed decline by 1.5 years on average later in life compared to within‐pair paternity success. These different trajectories indicate that the two alternative mating tactics should have age‐dependent pay‐offs. Males may partition their reproductive effort between within‐ and extra‐pair matings depending on their current age to reap the maximal combined benefit from both strategies. The interplay between these mating strategies and age‐specific mortality may explain the variation in rates of extra‐pair paternity observed within and between species. 相似文献