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41.
42.
The concentrations of 22 major and trace elements in livers from rats aging from 5 to 113 weeks old were determined. The rats investigated were the same rats previously reported with respect to 29 elements in bones (femur) and 26 elements in kidneys. The samples were decomposed with high-purity nitric acid and hydrogen peroxide. Seven elements (Na, Mg, P, K, Ca, Fe and Zn) were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES), and 15 elements (Mn, Co, Cu, As, Se, Rb, Sr, Mo, Cd, Sn, Sb, Cs, Ba, Pb and Bi) were determined by inductively coupled plasma mass spectrometry (ICP-MS). Analysis of variance (ANOVA) for age variations indicated that the concentrations of many elements, such as Mg, P, K, Mn, Fe, Cu, Zn, Sr, Mo and Cd, were almost constant across the ages of the rats with the exception of 5 weeks old (p > 0.05). Arsenic, Pb and Bi showed significant increasing trends, while Na and Co showed decreasing trends (p < 0.01). Selenium showed a decreasing trend except at the initial stage of 5–9 weeks old. Calcium, Rb, Sn, Sb, Cs and Ba showed significant age-related variations, but their patterns were not monotonic. The liver clearly contrasts with the kidneys, in which many elements showed significant age-related variations with increasing trends. The concentration ranges of Mg, P, K, Mn, Cu, Zn, and Mo were controlled within 15% across all ages of rats. The homeostasis of the aforementioned elements may be well established in the liver. The toxic elements, such as Cd, Pb and Bi, showed a narrow concentration range among age-matched rats.  相似文献   
43.
The nature of aromatic amino acid residues in Japanese-radish peroxidase a and the apoprotein was investigated by means of spectrophotometry and fluorospectrophotometry. The tyrosine residues in the holoenzyme were masked in the alkali-titration, giving an abnormally high value of 12.6, while they were exposed in the apoenzyme, exhibiting a value of 10.8. The difference spectra in the ultraviolet region between the holo-and apo-enzyme showed characteristic bands of tryptophan and phenylalanine as well as tyrosine. The perturbation of the aromatic amino acid residues by 50% ethyleneglycol was observed in the apoenzyme but not in the holoenzyme. The fluorophotometric experiments also revealed that the aromatic amino acid residues were in different environments in the holo- and apoenzyme. The difference between the conformation of peroxidase and that of the apoprotein was discussed.  相似文献   
44.
Japanese-radish root contained eighteen isoenzymes of peroxidase distinguishable on polyacrylamide gel electropherograms. The isoenzymes were found to be quite similar to those of horseradish peroxidase, although their quantities were different between two plants. The acidic components were the major isoenzyme in Japanese-radish peroxidase, while the neutral ones were the major one in horseradish. The chromatographic purification of the isoenzymes was performed on CM- and DEAE-Sephadex columns to characterize the components. The components in the preparations purified by the previously reported procedures of Morita et al. were also identified.  相似文献   
45.
All globulin components hitherto found in many species of seeds, α, β, γ and δ globulins, were identified in rice grain by ultracentrifugal experiments and gel-filtration chromatography. Among them, γ globulin was found to occur in high concentration in embryo and bran which were the most active parts in biological functions of rice grain. Then γ globulin was isolated from embryo by gel-filtration chromatography on a Sephadex G-200 column. Purified γ globulin was homogeneous in ultracentrifugal analysis and it was found to be insoluble in cold saline solution. On the other hand, α and β globulins were found to be more concentrated in endosperm with considerable heterogeneity.  相似文献   
46.
Nucleotides, 5′-AMP, 5′-GMP, 5′-UMP, 5′-CMP and 5′-TMP, in D2O solution have been investigated by proton magnetic resonance spectroscopy. The concentration and the pD dependences of the proton chemical shifts of the nucleotides have been examined in detail. These results indicate that intermolecular association of vertical stacking of the base rings and intramolecular association between base protons and ionized phosphate group occur in solution. The effects of the temperature and lithium ion on 5′-AMP and 5′-UMP have been also investigated. The increase of temperature causes to reduce the intramolecular association for 5′-UMP and the both intra- and intermolecular association for 5′-AMP. Lithium ion reduces the intramolecular association for both 5′-AMP and 5′-UMP, and at the same time promotes the intermolecular one for the former. This can be interpreted by the ion-pair formation of lithium ion with the ionized phosphate group.  相似文献   
47.
Hairy root clones of Scopolia japonica were established by selection of adventitious roots formed on the root segments inoculated with Agrobacterium rhizogenes strain 15834. Twenty-nine isolated hairy root clones displayed various phenotypes characterized by growth rate, opine production and tropane alkaloid production. Of these, two highly alkaloid productive clones SI and S22 were examined for their growth rate and alkaloid productivity under various cultural conditions. When the most scopolamine-productive clone SI was cultured for 4 weeks at 25°C in the dark, the weight of the root tissue was increased by 40 times and the content of scopolamine reached a level of 0.5% on a dry weight basis in each optimum medium. On culture of the most hyoscyamine-productive clone S22 under the same conditions as with S1, the weight was increased by 102 times and the content of hyoscyamine was 1.3% on a dry weight basis in each optimum medium.  相似文献   
48.
The homeobox protein, PEPP2 (RHOXF2), has been suggested as a cancer/testis (CT) antigen based on its expression pattern. However, the peptide epitope of PEPP2 that is recognized by cytotoxic T cells (CTLs) is unknown. In this study, we revealed that PEPP2 gene was highly expressed in myeloid leukemia cells and some other hematological malignancies. This gene was also expressed in leukemic stem-like cells. We next identified the first reported epitope peptide (PEPP2271-279). The CTLs induced by PEPP2271-279 recognized PEPP2-positive target cells in an HLA-A*24:02-restricted manner. We also found that a demethylating agent, 5-aza-2’-deoxycytidine, could enhance PEPP2 expression in leukemia cells but not in blood mononuclear cells from healthy donors. The cytotoxic activity of anti-PEPP2 CTL against leukemic cells treated with 5-aza-2’-deoxycytidine was higher than that directed against untreated cells. These results suggest a clinical rationale that combined treatment with this novel antigen-specific immunotherapy together with demethylating agents might be effective in therapy-resistant myeloid leukemia patients.  相似文献   
49.

Objective

When polymer brushes are applied as the inner coating for artificial blood vessels, they may induce unwanted responses in vascular endothelial cells continuously exposed to the polymer surface. Accordingly, we have examined the in vitro effect of non-biofouling concentrated polymer brushes (CPBs) on pro-inflammatory and angiogenic responses of human umbilical vein endothelial cells (HUVECs).

Results

Micro-patterned CPBs were prepared on silicon wafers using biocompatible polymers, poly(poly(ethylene glycol)methyl ether methacrylate) (PPEGMA) and poly(2-hydroxyethyl methacrylate) (PHEMA). HUVECs were cultured on PPEGMA-CPBs and PHEMA-CPBs with different channel widths (20, 50, and 80 µm) and analyzed for mRNA expression of the pro-inflammatory cytokines IL-6 and IL-8 and angiogeneic vascular endothelial growth factor (VEGF). Irrespective of channel width, PHEMA-CPBs reduced the expression of all target genes, whereas PPEGMA-CPBs reduced VEGF and did not affect IL-6 and IL-8 levels.

Conclusion

Micro-patterned CPBs, irrespective of chemical structure or adhesion area, do not induce the expression of important pro-inflammatory and angiogenic mediators in endothelial cells.
  相似文献   
50.
Fishery sustainability and the extinction risk of the Japanese eel, Anguilla japonica, are of global concern. The landings of the Japanese eel in Japan comprise a large part of the landings in East Asia. This study provides a compiled dataset of the annual fisheries statistics of the Japanese eel in Japan for stock assessment. The Japanese government has been recording Japanese eel statistics annually since 1984 in five series of annual reports by conducting systematic questionnaire surveys of fisheries managers and associations; however, most of these data are stored in analog format. The key variables in the dataset include the harvest weight of eels, the harvest weight and number of seeds for aquaculture, the number of eels stocked, and the number of management entities engaged in the eel fishery. The levels of spatial aggregation of the variables include the site (river and lake), prefecture, inland and coastal waters, and total in Japan. We also incorporated location data (latitude and longitude) of the site and prefecture into the dataset. Eel harvest includes primarily yellow eels (late juvenile stage) and silver eels (mature stage). Seed harvest in inland waters includes glass eels (intermediate stage between leptocephalus and elver) and elvers (early juvenile stage). Seed harvest from coastal waters comprises glass eels. This dataset provides information to assess long-term trends in the Japanese eel population.  相似文献   
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