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951.
Zhiyong Deng Yin Li Ran Xia Weiquan Wang Xiahe Huang Ling Zhang Shengli Zhang Cuiping Yang Yiyue Zhang Mingsheng Chen Qi Xie 《Genomics》2009,94(5):324-332
Salt cress (Thellungiella halophila) has become a desirable plant model for molecular analysis of the mechanisms of salt tolerance. Analysis of its physiological action and expressed EST has resulted in better understanding. However, less is known about its genomic features. Here we determined a continuous sequence approximately 83 kb from a salt cress BAC clone, providing the first insight into the genomic feature for this species. The gene density is approximately one gene per 3.6 kb in this sequence. Many types of repetitive sequences are present in this salt cress sequence, including LTR retroelements, DNA transposons and a number of simple sequence repeats. Comparison of sequence similarity indicated that salt cress shares a close relationship with Arabidopsis. Extensive conservation and high-level microcolinearity were uncovered for both genomes. Our study also indicated that genomic DNA alternations (involving chromosome inversion, sequence loss and gene translocation) contributed to the genomic discrepancies between salt cress and Arabidopsis. 相似文献
952.
Dietary supplementation with Chinese herbal powder enhances ileal digestibilities and serum concentrations of amino acids in young pigs 总被引:1,自引:0,他引:1
Kong XF Yin YL He QH Yin FG Liu HJ Li TJ Huang RL Geng MM Ruan Z Deng ZY Xie MY Wu G 《Amino acids》2009,37(4):573-582
This study was designed to determine the effect of ultra-fine Chinese herbal powder as a dietary additive on serum concentrations and apparent ileal digestibilities (AID) of amino acids (AA) in young pigs. In Experiment 1, 60 Duroc x Landrace x Yorkshire piglets weaned at 21 days of age were randomly assigned to one of three treatments, representing supplementation with 0 or 2 g/kg of the powder, or 0.2 g/kg of colistin (an antibiotic) to corn- and soybean meal-based diets (n = 20 per group). Blood samples from five piglets per group were collected on days 7, 14, and 28 to determine serum AA concentrations. In Experiment 2, 12 barrows with an average initial body weight of 7.64 kg were randomly assigned to one of the three dietary treatments, followed by surgical placement of a simple T-cannula at the terminal ileum. All of the diets contained 0.1% titanium oxide as a digestibility marker. The samples of terminal ileal digesta were collected on day 7 for determining AID of AA. Results show that dietary supplementation with the herbal powder increased (P < 0.05) serum concentrations and AID of most AA by 10-50% and 10-16%, respectively. As an indicator of improved intestinal function, AID values of calcium were also enhanced in piglets supplemented with the herbal powder. Dietary supplementation of colistin increased serum concentrations and AID values of some AA by 8-44% and 10-15%, respectively, in comparison with the non-supplemented group. These novel findings demonstrate that the herbal powder can enhance the digestibility of dietary protein and the intestinal absorption of AA into the systemic circulation in post-weaning pigs, therefore providing a new mechanism for its growth- and immunity-promoting efficacy. 相似文献
953.
Ji-Yuan Sun Hao Yang Shan Miao Ji-Peng Li Si-Wang Wang Miao-Zhang Zhu Yan-Hua Xie Jian-Bo Wang Zhe Liu Qian Yang 《Phytomedicine》2009,16(11):1070-1074
Swainsonine, an extract from Astragalus membranaceus, is known for its anti-cancer effects and could prevent metastases. In order to investigate the effects and mechanisms of swainsonine in C6 glioma cells, we carry out correlated experiments in vitro and in vivo. After treatment with swainsonine, the effective dose and IC50 value of swainsonine in the C6 glioma cell were examined using the MTT assay. Cell cycle distribution and apoptotic rates were analyzed using FCM and [Ca2+]i was measured by LSCM. Expressions of p16 and p53 protein were evaluated by immunocytochemical methods. Simultaneously, glioma-bearing rats were administered swainsonine at doses of 2, 4 and 8 mg/kg body wt. The inhibition rate was calculated and pathological sections were observed. The results indicated that the growth of C6 glioma cells is inhibited by swainsonine in vitro, with an IC50 value within 24 h of 0.05 μg/ml. Increases in swainsonine correlate with S phase percentages of 11.3%, 11.6% and 12.4%, respectively. Moreover, the expression of apoptosis inhibiting p53 and p16 protein decreases gradually. Tumor weight in vivo decreased clearly and HE dyeing of tumor tissue showed gray, its texture was soft, with necrosis and hemorrhagic concentrated inward. Swainsonine could inhibit the proliferation of C6 glioma cells in vitro and the growth of C6 glioma in vivo. The mechanisms of swainsonine-induced apoptosis may relate with the expression of apoptosis-related genes and overloading-[Ca2+]i-induced endoplasmic reticulum stress. 相似文献
954.
Yi Chen Ming‐Yong Xie Yuan‐Xing Wang Shao‐Ping Nie Chang Li 《Phytochemical analysis : PCA》2009,20(6):503-510
Introduction – Ganoderma, one of the best‐known traditional Chinese medicines, has attracted considerable attention owing to the fact that dozens of polysaccharides isolated from it have shown diverse and potentially significant pharmacological activities. However, no work has been reported on the analysis of monosaccharide composition of polysaccharide isolated from the aqueous extract of Ganoderma atrum yet. Objective – To develop a simple and sensitive GC‐based method for the analysis of monosaccharide composition of purified polysaccharides in Ganoderma atrum. Methodology – The polysaccharide was first hydrolysed to give the constituent monosaccharides, which were subsequently derived into acetylated aldononitriles and analysed by gas chromatography using a capillary column packed with a (5%phenyl) methylpolysiloxane stationary phase with the addition of acetyl inositol as the inner standard. High‐performance liquid chromatography was also used for comparison. Results – The stable derivatives of the most common monosaccharides could be separated and reproducibly determined with high sensitivity. The limits of detection and quantification were 0.013 and 0.043 mg/mL, respectively. The intermediary precision values (expressed as the RSD) were less than 10%. The mean recovery of the method was 100 ± 3%, with RSD values of less than 5%. The results obtained from GC and HPLC methods were found to be close to each other within acceptable error ranges. Conclusion – This study demonstrated that the developed method could be applied as an accurate method for the compositional analysis of monosaccharides in the field of biological and biochemical study. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
955.
956.
Xinfeng Xie Barry Goodell Dajie Zhang Dennis C. Nagle Yuhui Qian Michael L. Peterson Jody Jellison 《Bioresource technology》2009,100(5):1797-1802
In this study the oxidative behavior of carbons derived from cellulose and lignin were compared using thermogravimetric analysis (TGA). Specific surface area and chemical composition of the two types of carbon were analyzed using nitrogen adsorption at 77 K and infrared spectroscopy respectively. The results demonstrate that cellulose carbon has a higher reaction order and lower activation energy than lignin carbon under identical experimental conditions when they were prepared at temperatures lower than 500 °C. However, such differences were considerably reduced for the carbon samples prepared at temperatures greater than 700 °C. It was verified that lignin carbon is more stable than cellulose carbon due to its higher content of aromatic structures when they are prepared at lower temperature. The specific surface area and porosity have a more limited contribution to the differential oxidative behaviors of the two types of carbon. This research has significance related to the formation of carbon nanotubes from plant materials during low temperature carbonization. 相似文献
957.
Xingtao Tian Bingjie Qin Hong Lu Weihong Lai Shibo Jiang Kuo-Hsiung Lee Chin Ho Chen Lan Xie 《Bioorganic & medicinal chemistry letters》2009,19(18):5482-5485
Two series (4 and 5) of diarylpyridine derivatives were designed, synthesized, and evaluated for anti-HIV-1 activity. The most promising compound, 5e, inhibited HIV-1 IIIB, NL4-3, and RTMDR1 with low nanomolar EC50 values and selectivity indexes of >10,000. The results of this study indicate that diarylpyridine can be used as a novel scaffold to derive a new class of potent NNRTIs, active against both wild-type and drug-resistant HIV-1 strains. 相似文献
958.
Peng Du Ying-Hua Ling Xian-Chun Sang Fang-Ming Zhao Rong Xie Zheng-Lin Yang Guang-Hua He 《Genes & genomics.》2009,31(2):165-171
A mutant, which derived from the restorer line Jinhui10 treated with EMS, showed completely yellow green leaves, and it had low chlorophyll content and poor agronomic characteristics during the growing stage. The F1 plants from the cross between normal × the mutant showed normal green leaves, and the segregation ratio of normal to yellow green leaves was 3 : 1 in F2 population. It indicated that the trait was controlled by a single recessive nuclear gene, temporarily designated asygl3. The geneygl3 was mapped between RM468 and RM3684 with genetic distances 8.4 cM and 1.8 cM on chromosome 3. This result would be used as genetic information for fine mapping and map-based cloning ofygl3 gene. 相似文献
959.
Xue-Feng Wu Chun-Lian Wang En-Bei Xie Ying Gao Ying-Lun Fan Pi-Qing Liu Kai-Jun Zhao 《Planta》2009,229(6):1231-1242
We have previously isolated a Brassica juncea cDNA encoding a novel chitinase BjCHI1 with two chitin-binding domains (Zhao and Chye in Plant Mol Biol 40:1009–1018, 1999). The expression of BjCHI1 was highly inducible by methyl jasmonate (MeJA) treatment, wounding, caterpillar feeding, and pathogenic fungal infection.
These observations suggest that the promoter of BjCHI1 gene might contain specific cis-acting elements for stress responses. Here, we report the cloning and characterization of the BjCHI1 promoter. A 1,098 bp BjCHI1 genomic DNA fragment upstream of the ATG start codon was isolated by PCR walking and various constructs were made by fusing
the BjCHI1 promoter or its derivatives to β-glucuronidase reporter gene. The transgenic Arabidopsis plants showed that the BjCHI1 promoter responded to wounding and MeJA treatment, and to treatments with either NaCl or polyethyleneglycol (PEG 6000), indicating
that the BjCHI1 promoter responses to both biotic and abiotic stresses. A transient gene expression system of Nicotiana benthamiana leaves was adopted for promoter deletion analysis, and the results showed that a 76 bp region from −695 to −620 in the BjCHI1 promoter was necessary for MeJA-responsive expression. Furthermore, removal of a conserved T/G-box (AACGTG) at −353 to −348
of the promoter greatly reduced the induction by MeJA. This is the first T/G-box element identified in a chitinase gene promoter.
Gain-of-function analysis demonstrated that the cis-acting element present in the 76 bp region requires coupling with the T/G-box to confer full magnitude of BjCHI1 induction by MeJA. 相似文献
960.