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951.
Impacts of cell surface characteristics on population dynamics in a sequencing batch yeast reactor treating vegetable oil-containing wastewater 总被引:1,自引:0,他引:1
Ten yeast strains acquired from different sources and capable of utilizing vegetable oil or related compounds (fatty acid
or oleic acid) as sole carbon sources were inoculated into a sequencing batch reactor (SBR) for the treatment of high-strength
vegetable oil-containing wastewater. The SBR system stably removed >89% of chemical oxygen demand (COD) and >99% of oil when
fed with wastewater containing 15 g/L COD and 10 g/L oil in average. Denaturing gradient gel electrophoresis of polymerase
chain reaction-amplified 26S rRNA genes showed that among the ten yeast strains, only Candida lipolytica, Candida tropicalis, and Candida halophila were dominant in the system. To elucidate the major factors affecting the selection of yeast strains in the SBR system, the
three dominant strains were compared with two non-dominant strains in terms of COD removal performance, biomass yield, cell
settleability, cell flocculation ability, cell emulsification ability, and surface hydrophobicity. Results showed that hydrophobicity
and emulsification ability of yeast cells were the two most important factors determining the selection of yeast strains in
the treatment of high-strength oil-containing wastewater. 相似文献
952.
953.
Chia-Hsuan Chen Hsiu-Lin Huang Mu-Tzu Chang Li-Chia Chiang Shih-Lin Cheng Bing-Tsan Liu Chih-Hua Wang Ming-Che Wu Mu-Chiou Huang 《Biologia》2011,66(6):1196-1201
The complete mitochondrial genome sequence of the Formosan sambar (Rusa unicolor swinhoei) was obtained by DNA sequencing based on PCR fragments amplified by 26 primer pairs designed by ourselves. The results indicated
that the mtDNA is 16,505 bp in size. This is the first report on mitochondrial DNA (mtDNA) sequence analysis of the Formosan
sambar and the sequence was deposited in the GenBank database under the accession number DQ989636. The complete mitochondrial
sequence included the following gene sequences: 12S and 16S rRNAs, 22 tRNAs and 13 protein-coding genes. The base composition
of the sequence was as follows: A, 33.51%; T, 28.97%; C, 24.07%; and G, 13.46%. The mitochondrial D-loop region was also analyzed
for comparative purposes in the Formosan sambar and 13 other species within the Cervidae family using neighbour-joining method.
The phylogenetic tree demonstrated that there are two separate groups, a European type and an Asian type, within the Cervidae
family. The D-loop sequences of mtDNA of 24 Formosan sambar animals were compared, and the results showed that the Formosan
sambar can be divided into two clades. 相似文献
954.
A new Mn(II) complex, [Mn2(edta)(H2O)]n·nH2O (1) (H4edta = ethylenediaminetetraacetic acid) has been synthesized by the reaction of MnCl2·4H2O and H4edta under hydrothermal conditions, and was characterized by single-crystal X-ray diffraction study, variable temperature (1.8-300 K) magnetic measurement, and thermal gravity analysis. The result of X-ray crystallographic analysis reveals that complex 1 is the first two-dimensional (2D) Mn-edta coordination polymer with a grid-like (4,4)-topology, which is built from Mn-carboxylate chains and entirely deprotonated edta4− ligands with a maximum denticity. The variable temperature magnetic data indicate that complex 1 exhibits strong antiferromagnetic couplings. 相似文献
955.
956.
Li J Dong Z Liu B Zhuo Y Sun X Yang Z Ge J Tan Z 《Biochemical and biophysical research communications》2011,(1):40-44
Beta-amyloid (Aβ) derived from amyloid precursor protein (APP) has been associated with retinal degeneration in Alzheimer’s disease (AD) and glaucoma. This study examined whether hypoxia exposure induces Aβ accumulation in RGC-5 cells. While levels of APP mRNA and protein significantly increased in the cells, elevated abundance of Aβ was also observed in cells and culture medium between 12 or 24 and 48 h after 5% O2 hypoxia treatment. Additionally, there is a close relationship between induction of APP and Aβ and intracellular accumulation of ROS along with loss of mitochondrial membrane potential followed by the death of RGC-5 cells in culture under hypoxia. These results suggest a possible involvement of APP and Aβ in the death of RGCs challenged by hypoxia. 相似文献
957.
Liu L Lanner F Lendahl U Das D 《Biochemical and biophysical research communications》2011,(3):426-431
Numb serves as a key regulator of Notch and Sonic Hedgehog signaling and also modulates p53 protein levels. Numblike is a highly conserved homolog to mammalian Numb, but considerably less is known about its function. To address the role of Numblike, we have generated a mouse embryonic stem (ES) cell line, NblTetOn, in which expression of Numblike can be induced and analyzed the effect of activation of Numblike. Induction of Numblike, similar to Numb, reduced the amount of Notch receptor, whereas Numblike differed from Numb with regard to p53 and Shh signaling. In contrast to Numb, Numblike did not elevate the level of p53 protein and Numblike potentiated, rather than reduced, the immediate downstream response of Shh signaling. In keeping with a role for Numblike in potentiating Shh signaling, Shh and Numblike synergistically increased the proportion of ES cells expressing pluripotency markers. In conclusion, the data demonstrate that Numb and Numblike have evolved to acquire at least partially distinct functions. 相似文献
958.
During many infections, large numbers of effector CD8+ T cells are generated. After pathogen clearance, the majority of these cells undergo apoptosis, while the survivors differentiate into memory CD8+ T cells. Although loss of both Bim and Fas function dramatically increased antigen-specific CD8+ T cells in the lymph nodes following acute lymphocytic choriomeningitis virus (LCMV) infection, it was unclear whether they were pardoned effector or true memory CD8+ T cells. In this study, we demonstrate they are bona fide memory T cells as characterized by surface marker expression, cytokine production, homeostatic proliferation, and ability to clear a secondary challenge of pathogen. Loss of both Bim and Fas also increased the number of virus-specific CD4+ T cells found in the lymph nodes compared to the parental genotypes or wildtype mice. These studies illustrate that decreasing apoptosis increases the number of memory T cells and therefore could increase the efficacy of vaccines. 相似文献
959.
The migration of vascular endothelial cells plays a critical role in a variety of vascular physiological and pathological processes, such as embryonic development, angiogenesis, wound healing, re-endothelialization, and vascular remodeling. This study clarified the role and mechanism of a new vascular homeostasis regulator, Cellular repressor of E1A-stimulated genes (CREG), in the migration of primary human umbilical vein endothelial cells (HUVECs). A wound healing assay and transwell migration model showed that upregulation of CREG expression induced HUVEC migration and it was positively correlated with the expression of vascular endothelial growth factor. Furthermore, wild type integrin-linked kinase reversed the poor mobility of CREG knock-down HUVECs; in contrast, kinase-dead integrin-linked kinase weakened the migration of HUVECs. We also studied the effect of CREG on HUVEC migration by the addition of an mTOR inhibitor, recombinant vascular endothelial growth factor165, neutralizing antibody of vascular endothelial growth factor165 and AKT siRNA, and we concluded that CREG induces endothelial cell migration by activating the integrin-linked kinase/AKT/mTOR/VEGF165 signaling pathway. 相似文献
960.