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951.
952.
巢蛋白(nestin)属Ⅵ类中等纤维蛋白。最初在神经系统发育早期发现有该蛋白的表达。后在正常神经系统中发现仅在未分化的神经前体细胞中有nestin的短暂表达,分化后在神经元和神经胶质细胞中分别被NF(neurofilament,神经丝)和GFAP(Glial fibrillary acidic protein,神经胶质元纤维酸性蛋白)所代替。所以nestin的表达通常被视为神经前体细胞的标志之一。就我们所知,目前商品化nestin的抗体都是鼠抗鼠(克隆Rat401)的抗体,而人鼠之间该蛋白序列的同源性仅为50%左 相似文献
953.
Omid Etemadi Ioana G. Petrisor Daeik Kim Meng-Wei Wan Teh Fu Yen 《Soil & Sediment Contamination》2003,12(5):647-661
Environmental contamination with heavy metals and radionuclides remains a major problem worldwide. The current clean-up methodologies are based on energy-intensive engineering processes, which are disruptive and costly. A new universal technology targeted for the permanent enclosure and fixation of nuclear and other extreme hazardous metallic wastes in subsurface sites is needed. Such technology will be useful in treating contamination at many sites in the U.S., with specific applications to Department of Energy (DOE) sites. Biopolymers are potential tools for such an innovative technology. Biopolymers have repeated sequences, and therefore provide ample opportunity for chemical reactions with metals, soil particles, and other biopolymers. They also have the additional ability of creating cross-linking interpenetrating networks that can encapsulate the contaminants. Based on this concept, in the present work five biopolymers (xanthan, chitosan, polyhydroxy butyrate, guar gum, polyglutamic acid) were investigated for potential use in the stabilization of metals in the subsurface. The effects of these biopolymers (used alone and in combinations) on soil characteristics (permeability, shear strength) and their metal uptake ability have been studied using laboratory drainage flow systems. Biopolymer solutions were run through the experimental sandpack columns, followed by copper solution and leaching agents (distilled water and hydrochloric acid). The permeability and shear strength of sand were evaluated. Copper uptake capacity of each biopolymer and combination of biopolymers was also studied along with subsequent leaching. All biopolymers tested improved sand characteristics (by decreasing permeability and increasing shear strength) and had good metal uptake ability (60–90%) with relatively low leachability (10–22%). While biopolymers used alone were more efficient in metal uptake, the combination of two biopolymers (xanthan and chitosan) had an increasing plugging effect. These results show the potential of using biopolymers in subsurface metal stabilization. 相似文献
954.
A series of N-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl)thiocarbamates were synthesized by the reaction of glucosyl isothiocyanates with monohydric and dihydric alcohols, and acetone oxime, using methods of both normal reaction and microwave-assisted synthesis. Antifungal activities of the title compounds were determined with three kinds of plant pathogenic fungi, Fusarium graminearum, Rhizoctoria cerealis, and Colletotrichum orbiculare. The synthesized glucosyl thiocarbamates easily reacted with HgCl2 to give novel metal-organic compounds, bis[O-alkyl N-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl)thiocarbamato]mercury, in yields of 80%. This strong affinity of thiocarbamates for mercury showed their potential utility in medical or marine environmental detoxification. 相似文献
955.
Sue Mian Then Musalmah Mazlan Gapor Mat Top Wan Zurinah Wan Ngah 《Cellular and molecular neurobiology》2009,29(4):485-496
Besides acting as potent free radical scavengers, tocopherols and tocotrienols have been known to have non-antioxidant properties
such as the involvement of α-tocopherol (αT) in PKC pathway and the anti-cancer properties of γ-tocotrienol (γT3). This study
aims to elucidate whether protective effects shown by αT and γT3 in H2O2-induced neuron cultures have anti-apoptotic or pro-apoptotic tendency toward the initiation of neuronal apoptosis. H2O2 is used to induce apoptosis in primary cerebellar neuron cultures which is attenuated by pretreatment of αT or γT3 at concentrations
≤10 μM. Similar to our previous work, γT3 was found to be neurotoxic at concentrations ≥100 μM, whereas αT showed no neurotoxicity.
Cellular uptake of γT3 was higher than that of αT. Treating cells simultaneously with either γT3 or αT and with then H2O2 led to higher expression of Bax and Bcl-2 than in neurons exposed to H2O2 alone. Analysis of Bcl-2/Bax ratio as ‘survival index’ showed that both pretreatment of γT3 and αT followed by H2O2 increase the ‘survival index’ of Bcl-2/Bax ratio compared to H2O2-treated cells, while treatment of γT3 alone decrease the ratio compared to unchanged Bcl2/Bax ratio of similar treatment
with αT alone. Similar treatment of γT3 decreased p53 expression and activates p38 MAPK phosphorylation, whereas αT did not
alter its expression compared to H2O2-treated cells. Treating neurons with only γT3 or αT increased the expression of Bax, Bcl-2, p53, and p38 MAPK compared to
control with γT3 exerting stronger expression for proteins involved than αT. In conclusion, low doses of γT3 and αT confer
neuroprotection to H2O2-treated neurons via their antioxidant mechanism but γT3 has stronger pro-apoptosis tendency than αT by activating molecules
involved in the neuronal apoptotic pathway in the absence of H2O2. 相似文献
956.
Ming Zhang Chunling Wan Baohu Ji Zhao Zhang Hui Zhu Nan Tian Yujuan La Ke Huang Lei Jiang Guang He Linhan Gao Xinzhi Zhao Yongyong Shi Gang Huang Guoyin Feng Lin He 《Molecular and cellular biochemistry》2009,323(1-2):185-193
Retinoic acid (Ra) is crucial for the patterning and neuronal differentiation in the central nervous system (CNS). Ra deficiency in animals disrupts the motor activities and memory abilities. The molecular mechanisms underlying these behavior abnormalities remain largely unknown. In the current study, we treated the astrocytoma cells with citral, an inhibitor of Ra synthesis. We analyzed the differences in the protein concentrations between the treated and untreated astrocytoma cells by two-dimensional gel electrophoresis (2-DE), Imagemaster software, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). In total, 39 of 46 altered protein spots with significant mascot scores were identified representing 36 proteins, that were involved in significantly altered glutamate metabolism, lipid metabolism, mitochrondrial function, and oxidative stress response by Ingenuity Pathway Analysis (IPA). Altered 3-phosphoglycerate dehydrogenase (PHGDH) was also observed in western blot. These data provide some clues for explaining the behavioral changes caused by Ra deficiency, and support the hypothesis that Ra signaling is associated with some symptoms of neurodegenerative disorders and schizophrenia. 相似文献
957.
Jae Woong Sull Kung-Yee Liang Jacqueline B. Hetmanski Tao Wu Margaret Daniele Fallin Roxann G. Ingersoll Ji Wan Park Yah-Huei Wu-Chou Philip K. Chen Samuel S. Chong Felicia Cheah Vincent Yeow Beyoung Yun Park Sun Ha Jee Ethylin Wang Jabs Richard Redett Alan F. Scott Terri H. Beaty 《Human genetics》2009,126(3):385-394
This study examined the association between markers in transforming growth factor alpha (TGFA) and isolated, non-syndromic cleft lip with/without palate (CL/P) using a case–parent trio design, considering parent-of-origin effects. We also tested for gene–environmental interaction with common maternal exposures, and for gene–gene interaction using markers in TGFA and another recognized causal gene, IRF6. CL/P case–parent trios from four populations (76 from Maryland, 146 from Taiwan, 35 from Singapore, and 40 from Korea) were genotyped for 17 single nucleotide polymorphisms (SNPs) in TGFA. The transmission disequilibrium test was used to test individual SNPs, and the parent-of-origin likelihood ratio test (PO-LRT) was used to assess parent-of-origin effects. We also screened for possible gene–environment interaction using PBAT, and tested for gene–gene interaction using conditional logistic regression models. When all trios were combined, four SNPs showed significant excess maternal transmission, two of which gave significant PO-LRT values [rs3821261: P = 0.004 and OR(imprinting) = 4.17; and rs3771475: P = 0.027 and OR(imprinting) = 2.44]. Haplotype analysis of these two SNPS also supported excess maternal transmission. We saw intriguing but suggestive evidence of G × E interaction for several SNPs in TGFA when either individual SNPs or haplotypes of adjacent SNPs were considered. Thus, TGFA appears to influence risk of CL/P through unconventional means with an apparent parent-of-origin effect (excess maternal transmission) and possible interaction with maternal exposures. 相似文献
958.
Lai Hong Fu Yansong Miao Sze Wan Lo Tai Chi Seto Samuel S.M. Sun Zeng-Fu Xu Sabine Clemens Lorne A. Clarke Allison R. Kermode Liwen Jiang 《Plant science》2009,177(6):668-675
Lysosomal storage diseases (LSDs), that collectively represent over 50 disorders, are amenable to enzyme replacement therapies. However, the current methods used to commercially produce recombinant lysosomal enzymes for this purpose, most commonly Chinese Hamster Ovary cells and human fibroblasts, are prohibitively costly. Plant bioreactors hold great promise for economic production of functional human α-l-iduronidase (hIDUA; glycosaminoglycan α-l-iduronohydrolase; EC 3.2.1.76), the enzyme deficient in the human LSD, Mucopolysaccharidosis I. We have developed and tested an expression system using transgenic tobacco BY-2 cells to produce high amounts of active hIDUA. A plant signal peptide was essential for proper expression and secretion of the 78 kDa glycosylated hIDUA into the cultured media of transgenic BY-2 cells. The yield and activity of the secreted hIDUA from long-term cultures of transgenic BY-2 cell lines were as high as 10 μg/mL media and 53,000 pmol/min/mg proteins, respectively. Thus, this transgenic BY-2 cell line presents an attractive platform for economic production and easy downstream purification of hIDUA for enzyme replacement therapy. Furthermore, this system can be used for the production and purification of other human lysosomal enzymes or pharmaceuticals. 相似文献
959.
Mee Lee Looi Saiful Anuar Karsani Mariati Abdul Rahman Ahmad Zailani Hatta Mohd Dali Siti Aishah Md Ali Wan Zurinah Wan Ngah Yasmin Anum Mohd Yusof 《Journal of biosciences》2009,34(6):917-925
Although cervical cancer is preventable with early detection, it remains the second most common malignancy among women. An understanding of how proteins change in their expression during a particular diseased state such as cervical cancer will contribute to an understanding of how the disease develops and progresses. Potentially, it may also lead to the ability to predict the occurrence of the disease. With this in mind, we aimed to identify differentially expressed proteins in the plasma of cervical cancer patients. Plasma from control, cervical intraepithelial neoplasia (CIN) grade 3 and squamous cell carcinoma (SCC) stage IV subjects was resolved by two-dimensional gel electrophoresis and the resulting proteome profiles compared. Differentially expressed protein spots were then identified by mass spectrometry. Eighteen proteins were found to be differentially expressed in the plasma of CIN 3 and SCC stage IV samples when compared with that of controls. Competitive ELISA further validated the expression of cytokeratin 19 and tetranectin. Functional analyses of these differentially expressed proteins will provide further insight into their potential role(s) in cervical cancer-specific monitoring and therapeutics. 相似文献
960.
Yong Kyoung Lee Im Seop Choi Young Heui Kim Ki Ho Kim Sang Yun Nam Young Won Yun Moon Soon Lee Ki Wan Oh Jin Tae Hong 《Neurochemical research》2009,34(12):2251-2260
Compounds isolated from Magnolia officinalis such as magnolol, honokiol and obovatol exhibit several pharmacological effects on CNS including depressant, anxiolytic and
anticonvulsant effects, as well as neuroprotective effects against chemical and heat damages. Recently, honokiol was found
to have a neurotrophic effect in fetal rat cortical neurons. In the present study, we show that 4-O-methylhonokiol, a novel compound from Magnolia officinalis, promotes neurite outgrowth in a concentration-dependent manner in rat embryonic neuronal cells. In parallel with the neurite
outgrowth activity, the expression of neurite outgrowth marker proteins is also increased by treatment with 4-O-methylhonokiol. We also found that 4-O-methylhonokiol promotes the release of NGF and BDNF into cell culture medium. In addition, lower concentration of 4-O-methylhonokiol (1 and 2 μM) further enhanced neurite outgrowth and expression of neurite outgrowth marker proteins in the
presence of NGF (50 ng/ml) or BDNF (10 ng/ml). Subsequently, we found that 4-O-methylhonokiol activates ERK in a concentration-dependent manner. However, the neurite outgrowth activity and the NGF and
BDNF release induced by 4-O-methylhonokiol are suppressed by an ERK-specific inhibitor. These results suggest that 4-O-methylhonokiol has the ability to induce neurite outgrowth via the increase of neurotrophic factor levels through ERK activation. 相似文献