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61.
The present investigation deals with the determination of various serum enzymes known to be elevated during myocardial infarction (MI) and estimation of selected metals like Cu, Cr, Co, Fe, Pb, and Mg by flame atomic absorption spectrophotometry. The data obtained thereby were processed for the determination of correlation coefficient matrix among the cardiac enzymes and the serum metals. The study evidenced the accumulation of Pb during MI and reduction in the level of Fe. A significant negative correlation was observed between Cu and creatine kinase-MB. The data were also segregated into various groups to study the influence of age and gender on the levels of selected parameters. In both the genders, the age of the patients was found to be correlated significantly with various cardiac enzymes. In case of male patients, the most significant correlation was observed between age and blood sugar at random. The other significant correlations among the male patients included Cr–CPK, Cr–creatine kinase-MB, Fe–age, and others. In female patients, the pairs of studied parameters that exhibited significant correlations included age–lactic dehydrogenase, creatine phosphokinase isoenzyme–aspartate aminotransferase, lactic dehydrogenase–creatine phosphokinase isoenzymes, Pb-Fe, and Cu-Co in addition to others. 相似文献
62.
Samples of whole blood were obtained from 51 patients with newly diagnosed colorectal cancer as well as from 76 patients with neoplastic colorectal polyp, and from 30 healthy blood bank donors. Selenium was determined by the fluorimetric method. Significantly decreased selenium concentrations of blood samples from patients with colorectal cancer and villous adenoma were found. There was not any correlation between the blood selenium levels of patients with adenomatous polyp and the severity of dysplasia in removed polyps. The lowest mean selenium level in patients with villous adenoma indicates that selenium deficiency may be an important factor in the development of colorectal cancer arising from villous adenomas. 相似文献
63.
Munkhzul Ganbold Yasuhiro Shimamoto Farhana Ferdousi Kenichi Tominaga Hiroko Isoda 《Biochemistry and Biophysics Reports》2019
Quercetin (QCT) and isorhamnetin (ISO), natural flavonoids, were both shown to possess antifibrotic activity in in vivo and in vitro models of hepatic fibrosis. Although ISO is a direct metabolite of QCT differing by a methyl group, it has been reported to be absorbed more adequately and eliminated slower than QCT after oral administration. Our aim of the study was to investigate biological effect of mono-methylated QCT derivatives against fibrosis using rat hepatic stellate cells (HSC-T6). All test derivatives were synthesized from QCT. HSC-T6 cells were induced by TGFβ and treated with derivatives followed by cell proliferation assay, immunofluorescence staining of αSMA, and gene expression analysis of fibrosis markers. All compounds showed a dose- and time-dependent antiproliferation effect. ISO, 3-O-methylquercetin (3MQ), and rhamnetin (RHA) reduced αSMA mRNA; 3MQ prevented the augmentation of collagen I mRNA; and compounds, except azaleatin and 3MQ, reduced Timp1 mRNA expression in TGFβ-induced HSCs. In conclusion, each compound had singular effect against different features of fibrosis depending on the position of methyl group although the further mechanism of action of compounds during fibrosis development remains to be investigated. These findings suggest that antifibrotic effect of quercetin can be enhanced by adding methyl group on functionally important position. 相似文献
64.
The maximum productivity of -glucosidase by Saccharomyces cerevisiaerecombinants under the control of GALI promoter was 100 IU l–1 h–1. The highest productivity of -glucosidase by a S. cerevisiae recombinant was 16-fold more than that supported by Cellulomonas biazotea. The recombinants also co-produced ethanol from cellobiose: maximum product yield and productivity were 0.5 and 1.1 g ethanol g–1 cellobiose and g ethanol l–1 h–1, respectively. 相似文献
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67.
M.E. Sales R.I. Baraao L.S. Rumi A. Tenenbaum E.S. Borda 《Prostaglandins, leukotrienes, and essential fatty acids》1992,47(4)
Prostaglandin E2 (PGE2) and cAMP production in allogeneic and syngeneic pregnant mice uteri, were measured in relation to the ratio of plasma estrogen/progesterone levels. PGE2 generation by allopregnant uteri varied with the days of pregnancy. The increment of the prostanoid coincided with the increase in plasma estrogen concentration, whereas the decrement of its production was in parallel with the increment of plasma progesterone. The syngeneic pregnant uterus was unable to increase the release of PGE2 above basal values during the whole pregnancy. The rise of PGE2 production by the allogeneic pregnant uterus was correlated with an increase in cAMP levels. It is proposed that the pregnant mouse uterus increases its ability to release PGE2 in response to an ovarian steroids. 相似文献
68.
Chie Shibazaki Shigeki Arai Rumi Shimizu Morihisa Saeki Takayoshi Kinoshita Andreas Ostermann Tobias E. Schrader Yuzuru Kurosaki Tomoko Sunami Ryota Kuroki Motoyasu Adachi 《Journal of molecular biology》2018,430(24):5094-5104
Casein kinase 2 (CK2) has broad phosphorylation activity against various regulatory proteins, which are important survival factors in eukaryotic cells. To clarify the hydration structure and catalytic mechanism of CK2, we determined the crystal structure of the alpha subunit of human CK2 containing hydrogen and deuterium atoms using joint neutron (1.9 Å resolution) and X-ray (1.1 Å resolution) crystallography. The analysis revealed the structure of conserved water molecules at the active site and a long potential hydrogen bonding network originating from the catalytic Asp156 that is well known to enhance the nucleophilicity of the substrate OH group to the γ-phospho group of ATP by proton elimination. His148 and Asp214 conserved in the protein kinase family are located in the middle of the network. The water molecule forming a hydrogen bond with Asp214 appears to be deformed. In addition, mutational analysis of His148 in CK2 showed significant reductions by 40%–75% in the catalytic efficiency with similar affinity for ATP. Likewise, remarkable reductions to less than 5% were shown by corresponding mutations on His131 in death-associated protein kinase 1, which belongs to a group different from that of CK2. These findings shed new light on the catalytic mechanism of protein kinases in which the hydrogen bond network through the C-terminal domain may assist the general base catalyst to extract a proton with a link to the bulk solvent via intermediates of a pair of residues. 相似文献
69.
David A. Schaer Richard P. Beckmann Jack A. Dempsey Lysiane Huber Amelie Forest Nelusha Amaladas Yanxia Li Ying Cindy Wang Erik R. Rasmussen Darin Chin Andrew Capen Carmine Carpenito Kirk A. Staschke Linda A. Chung Lacey M. Litchfield Farhana F. Merzoug Xueqian Gong Philip W. Iversen Michael Kalos 《Cell reports》2018,22(11):2978-2994
70.
Rumi Sakamoto Eisuke Kakinuma Kentaro Masuda Yuko Takeuchi Kosaku Ito Kentaro Iketaki Takahisa Matsuzaki Seiichiro Nakabayashi Hiroshi Y. Yoshikawa Hideaki Yamamoto Yuko Sato Takashi Tanii 《In vitro cellular & developmental biology. Animal》2016,52(8):799-805
The main constituent of green tea, (?)-Epigallocatechin-3-O-gallate (EGCG), is known to have cancer-specific chemopreventive effects. In the present work, we investigated how EGCG suppresses cell adhesion by comparing the adhesion of human pancreatic cancer cells (AsPC-1 and BxPC-3) and their counterpart, normal human embryonic pancreas-derived cells (1C3D3), in catechin-containing media using organosilane monolayer templates (OMTs). The purpose of this work is (1) to evaluate the quantitativeness in the measurement of cell adhesion with the OMT and (2) to show how green-tea catechins suppress cell adhesion in a cancer-specific manner. For the first purpose, the adhesion of cancer and normal cells was compared using the OMT. The cell adhesion in different type of catechins such as EGCG, (?)-Epicatechin-3-O-gallate (ECG) and (?)-Epicatechin (EC) was also evaluated. The measurements revealed that the anti-adhesion effect of green-tea catechins is cancer-specific, and the order is EGCG?ECG>EC. The results agree well with the data reported to date, showing the quantitativeness of the new method. For the second purpose, the contact area of cells on the OMT was measured by reflection interference contrast microscopy. The cell-OMT contact area of cancer cells decreases with increasing EGCG concentration, whereas that of normal cells remains constant. The results reveal a twofold action of EGCG on cancer cell adhesion—suppressing cell attachment to a candidate adhesion site and decreasing the contact area of the cells—and validates the use of OMT as a tool for screening cancer cell adhesion. 相似文献