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991.
992.
Cytoglobin, generated using genetic engineering method, is a kind of recombinant human stellate cell activation-associated
protein. We speculate that it could influence the development of hepatic fibrosis like Sellate cell activation-associated
protein which was discovered by Kawada et al. Therefore, we investigated its anti-fibrosis effect on liver both in vivo and
in vitro. During our research, we found that cytoglobin showed obvious effect compared with the control group on Thioacetamide-induced
liver fibrosis in SD rats, including significantly decrease in aspartate aminotransferase, Hyaluronic acid, laminin and collagen
I(Col I) levels in serum and hydroxyproline in livers, which are the important indices reflecting the degree of hepatic fibrosis.
Meanwhile, the viability of rat hepatic stellate cell line T6 (HSC-T6) cells was inhibited by cytoglobin and the apoptosis
induced by cytoglobin in HSC-T6 cells was detected by Annexin V/PI double staining. Activation of the caspase cascade including
caspase-3 for the intrinsic pathways was demonstrated. The results also showed that the expression of Bcl-2 protein decreased
whereas that of Bax protein increased, leading to an increase of the Bax/Bcl-2 ratio. Our results demonstrated that cytoglobin
exhibited anti-fibrosis activity on livers in vivo and in vitro, involving apoptosis induction. 相似文献
993.
994.
Yao YW Shi Y Jia ZF Jiang YH Gu Z Wang J Aljofan M Sun ZG 《Histochemistry and cell biology》2011,136(2):205-215
To investigate the biological significance of ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) involvement in oocyte maturation,
we screened for proteins that bound to UCH-L1 in mouse ovaries, and we found that the prostate tumor overexpressed-1 (PTOV1)
protein was able to bind to UCH-L1. PTOV1 is highly expressed in prostate cancers and considered as a potential marker for
carcinogenesis and the progress of prostate cancer. It was reported that PTOV1 plays an important role in cell cycle regulation,
but its role in mammalian oocyte development and meiosis is still unclear. In this paper, it was found that the expression
levels of PTOV1 in mouse ovaries progressively increased from prepubescence to adulthood. And we found by immunohistochemistry
that PTOV1 spreaded in both the cytoplasm and nuclei of oocytes during prepuberty, but in normal adult mouse oocytes, it concentrated
not only in nuclei but also on the plasma membrane, though in some oocytes with abnormal shapes, PTOV1 did not display the
typical distribution patterns. In granulosa cells, however, it was found to locate in the cytoplasm at all the selected ages.
In postnatal mouse ovaries (28 days), estradiol treatment induced the adult-specific distribution pattern of PTOV1 in oocytes.
In addition, UCH-L1 was shown to be associated with CDK1, which participated in the regulation of cell cycle and oocyte maturation.
Therefore, we propose that the distribution changes of PTOV1 are age-dependent, and significant for mouse oocyte development
and maturation. Moreover, the discovery that PTOV1 is associated with UCH-L1 in mouse oocytes supports the explanations for
that UCH-L1 is involved in oocyte development and maturation, especially under the regulation of estrogen. 相似文献
995.
Mohamed A. Abdel-Naby Mona Y. Osman Ahmed F. Abdel-Fattah 《World journal of microbiology & biotechnology》2011,27(12):2903-2911
The production of extracellular pullulanase by Bacillus licheniformis NRC22 was investigated using different fermentation modes. In batch culture maximal enzyme activity of 18 U/ml was obtained
after 24 h of growth. In continuous fermentation by the free cells, maximal reactor productivity (4.15 KU/l/h) with enzyme
concentration of 14.8 U/ml and specific productivity of 334.9 U/g wet cells/h was attained at a dilution rate of 0.28/h, over
a period of 25 days. B. licheniformis NRC22 cells were immobilized on Ca-alginate. The immobilization conditions with respect to matrix concentration and cell
load was optimized for maximal enzyme production. In repeated batch operation, the activity of the immobilized cells was stable
during the 10 cycles and the activity remained between 9.8 and 7.7 U/ml. Continuous production of pullulanase by the immobilized
cells was investigated in a packed–bed reactor. Maximal reactor productivity (7.0 KU/h) with enzyme concentration of 16.8 U/ml
and specific productivity of 131.64 U/g wet cells/h was attained at dilution rate of 0.42/h. The enzyme activity in the effluent
started to decline gradually to the level of 8.7 U/ml after 25 days of the operation. 相似文献
996.
Liang Zhang Zhongyang Ding Peng Xu Yuhong Wang Zhenghua Gu Zhu Qian Guiyang Shi Kechang Zhang 《Biotechnology and Bioprocess Engineering》2011,16(3):457-461
Tyrosinase is a key enzyme in the biosynthesis of melanin, and the use of inhibitors against tyrosinase can prevent hyperpigmentation
by inhibiting enzymatic oxidation. However, the current use of tyrosine inhibitors is limited by their low activities and
high toxicities. The aim of the present research was to develop novel whitening agents, or tyrosinase-targeted medicine, from
a submerged culture of the fungus Ganoderma lucidum. Methyl lucidenate F was isolated from the ethanol-soluble-acidic components (ESACs) of G. lucidum, with the structure of ESACs elucidated via UV, LC-MS, and 13C-NMR spectral analysis. The tyrosinase inhibitory activity was measured using catechol as a substrate. Methyl lucidenate
F displayed uncompetitive inhibition of the potato tyrosinase activity, for which Lineweaver-Burk plots revealed a maximum
reaction rate (V
max) of 0.4367/min, Michaelis constant (K
m) of 6.765 mM and uncompetitive inhibition constant (K
i) of 19.22 μM. Meanwhile, methyl lucidenate F (tetra cyclic triterpenoid) exhibited high tyrosinase inhibitory activity, with
an IC50 of 32.23 μM. These results suggest that methyl lucidenate F may serve as a potential candidate for skin-whitening agents. 相似文献
997.
Non-target organism effects tests on Vip3A and their application to the ecological risk assessment for cultivation of MIR162 maize 总被引:1,自引:0,他引:1
Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) provide economic, environmental and health benefits by maintaining or increasing crop yields with fewer applications of
insecticide. To sustain these benefits, it is important to delay the evolution of insect resistance to the proteins, and to
ensure that the proteins do not harm non-target organisms, particularly those that may control secondary pests that would
otherwise flourish because of reduced insecticide applications. Vip3A is a Bt vegetative insecticidal protein that is active against lepidopterous pests. It has a different mode of action from other
proteins for control of Lepidoptera in current Bt crops, and when combined with these proteins, it should help to delay the evolution of pest resistance to Bt crops. This paper presents data on the effects of Vip3A on non-target organisms, and an ecological risk assessment of MIR162
maize, which expresses Vip3Aa20. Laboratory studies indicate few adverse effects of Vip3A to non-target organisms: 11 of 12
species tested showed no adverse effects when exposed to high concentrations of Vip3A relative to estimated exposures resulting
from cultivation of MIR162 maize. Daphnia magna exposed to Vip3Aa20 were unaffected in terms of survival or fecundity, but grew slightly more slowly than unexposed controls.
The data indicate that cultivation of MIR162 maize poses negligible risk to non-target organisms, and that crops producing
Vip3A are unlikely to adversely affect biological control organisms such that benefits from reduced insecticide applications
are lost. 相似文献
998.
The Brazilian Atlantic Forest is a Biodiversity Hotspot, yet many biological groups in this biome are poorly known. We compiled
information on the diversity of Atlantic Forest tiger moths (Arctiidae) and assessed the resemblance among localities, whether
arctiid assemblages are concordant with major vegetation types, and the importance of environmental factors in structuring
the variation among assemblages. Additionally, we developed a procedure composed of subsampling and procrustean analysis to
assess the robustness of the results from community composition ordinations when localities differ in species richness. To
do this, we built a database from specimens deposited in the ten most important Brazilian entomological collections, and mapped
species richness in one-degree latitude/longitude grid cells. We employed Principal Coordinates Analysis to assess similarities
among the best-sampled localities. We obtained 8,667 records including 1,193 species, representing 60 and 20% of the estimated
Brazilian and Neotropical faunas, respectively. Our subsampling procedure indicated that the ordination was not greatly affected
by differences in species richness, and was congruent with major vegetation types. Lowland localities on the seacoast were
quite distinct in species composition. A second group included localities in montane areas in the southeast part of the biome.
The last group included localities in the southern region and those with Araucaria forests, and was associated with long distances
from the ocean, even distribution of precipitation throughout the year, and large annual temperature ranges. 相似文献
999.
Gregory M. Peters Stephen Wiedemann Hazel V. Rowley Robyn Tucker Andrew J. Feitz Matthias Schulz 《The International Journal of Life Cycle Assessment》2011,16(5):431-441
Purpose
This paper describes part of the first detailed environmental life cycle assessment (LCA) of Australian red meat (beef and sheep meat) production. The study was intended to assist the methodological development of life cycle impact assessment by examining the feasibility of new indicators for natural resource management (NRM) issues relevant to soil management in agricultural LCA. This paper is intended to describe the NRM indicators directly related to agricultural soil chemistry. 相似文献1000.
Borovsky Y Paran I 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(4):657-665
We previously identified fs10.1 as a major QTL controlling fruit shape (index of length to width) in an interspecific F2 cross of Capsicum annuum (round fruit) × C. chinense (elongated fruit) in pepper. To more precisely map and characterize the QTL, we constructed near-isogenic lines for fs10.1 and mapped it in a BC4F2 population. In this population, fs10.1 segregated as a Mendelian locus and mapped 0.3 cM away from the closest molecular marker. We further verified the effect
of fs10.1 in an F2 population from an independent cross between elongated- and conical-fruited parents. To identify additional allelic variation
at fruit shape loci, we screened an EMS-mutagenized population of the blocky-fruited cv. Maor and identified the mutant E-1654
with elongated fruit. This fruit shape mutation was mapped to the fs10.1 region and was determined to be allelic to the QTL. By measuring fruit shape of near-isogenic lines for fs10.1 during fruit development, we found that the shape of the fruit is determined primarily in the first 2 weeks after anthesis.
Histological measurements of cell size and cell shape in pericarp sections of fruits of the isogenic lines throughout fruit
development indicated that the shape of the fruit is determined primarily by cell shape and that the development of fruit
shape is correlated with cell shape. 相似文献