997 resultados para GUS staining


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The winged bean (Psophocarpus tetragonolobus) agglutinin (total lectin) and its basic (WBA I) and acidic isoform (WBA II) were used to analyze capillaries in sections from human muscle. The microvessels were clearly labeled after incubation with the lectins in both normal muscle and in old muscles with age-related type II atrophy or muscle fiber grouping. Muscle fibers, nerves, and connective tissue remained unstained. The total lectin detected muscle capillaries from all blood group AB0 individuals. The isoform WBA I reacted only with blood vessels in blood group A and B individuals, while the blood vessels in blood group 0 individuals were demonstrated with WBA II. WBA I staining was inhibited by p-nitrophenyl α-galactopyranoside and N-acetylgalactosamine, whereas 2′-fucosyllactose and preincubation with an antibody against type-1 chain H abolished capillary staining with WBA II. The study demonstrates the usefulness of WBA as a marker of capillaries in human muscle.

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Vegetative cells and zygotes of Saccharomyces carlsbergensis fixed in iodine formaldehyde acetic acid solution and stained after acid hydrolysis in hæmatoxylin, Feulgen and Giemsa show a remarkable similarity in the size and orientation of the structures in the nuclear matrix with reference to the nuclear membrane. The nucleolus described by Guilliermond may either be the chromocenter or the nucleolar equivalent.

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Genetic transformation systems have been established for Brassica nigra (cv. IC 257) by using an Agrobacterium binary vector as well as by direct DNA uptake of a plasmid vector. Both the type of vectors carried nptII gene and gus gene. For Agrobacterium mediated transformation, hypocotyl tissue explants were used, and up to 33% of the explants produced calli on selection medium. All of these expressed B-glucuronidase gene on histochemical staining. Protoplasts isolated from hypocotyl tissues of seedlings could be transformed with a plasmid vector by FEG mediated uptake of vector DNA. A number of fertile kanamycin resistant plants were obtained using both the methods, and their transformed nature was confirmed by Southern blot analysis and histochemical staining for GUS. Backcrossed and selfed progenies of these transformed plants showed the presence of npt and gus genes.

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Planar triazinium cationic species, from VO2+-assisted cyclization of 1-(2-thiazolylazo)-2-naphthol, shows efficient DNA intercalative binding, visible light-induced anaerobic plasmid DNA photocleavage activity and photocytotoxicity in HeLa and MCF-7 cancer cells by an apoptotic pathway with selective localization of the compound in the nucleus as evidenced from the nuclear staining and confocal imaging.

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Planar triazinium cationic species from vanadyl-assisted cyclization of 1-(2-thiazolylazo)-2-naphthol (H-TAN, 1), 1-(2-pyridylazo)-2-naphthol (H-PAN, 2), 2-(2'-thiazolylazo)-p-cresol (H-TAC, 3) and 6-(2'-thiazolylazo)- resorcinol (H-TAR, 5) were prepared and characterized. A dioxovanadium(V) species VO2(TAR)] (4) was also isolated. Compounds 1, 2 and 4 were structurally characterized. Both 1 and 2 have planar structures. Complex 4 has (VO3N2)-O-V coordination geometry. The cyclised triazinium compound forms a radical species within -0.06 to -0.29 V vs. SCE in DMF-0.1 M tetrabutylammonium perchlorate with a second response due to formation of an anionic species. A confocal microscopic study showed higher nuclear uptake for 1 having a fused thiazole moiety than 2 with a fused pyridine ring. The compounds showed a partial intercalative mode of binding to calf thymus DNA. Compound 1 showed plasmid DNA photo-cleavage activity under argon and photocytotoxicity in HeLa and MCF-7 cells with IC50 values of 15.1 and 3.4 mu M respectively in visible light of 400-700 nm, while being essentially non-toxic in the dark with IC50 values of 90.4 and 21.9 mu M. ATDDFT study was done to rationalize the experimental data.

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A newly designed and structurally characterized cell permeable diformyl-p-cresol based receptor (HL) selectively senses the AsO33- ion up to ca. 4.1 ppb in aqueous media over the other competitive ions at biological pH through an intermolecular H-bonding induced CHEF (chelationenhanced fluorescence) process, established by detailed experimental and theoretical studies. This biofriendly probe is highly competent in recognizing the existence of AsO33- ions in a living organism by developing an image under a fluorescence microscope and useful to estimate the amount of arsenite ions in various water samples.

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A newly synthesized and structurally characterized quinazoline derivative (L) has been shown to act as a quick-response chemosensor for Al3+ with a high selectivity over other metal ions in water-DMSO. In the presence of Al3+, L shows a red-shifted ratiometric enhancement in fluorescence as a result of internal charge transfer and chelation-enhanced fluorescence through the inhibition of a photo-induced electron transfer mechanism. This probe detects Al3+ at concentrations as low as 1.48 nM in 100 mM HEPES buffer (DMSO-water, 1 : 9 v/v) at biological pH with a very short response time (15-20 s). L was applied to biological imaging to validate its utility as a fluorescent probe for monitoring Al3+ ions in living cells, illustrating its value in practical environmental and biological systems.

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A newly designed fluorescent aluminum(III) complex (L'-Al; 2) of a structurally characterized non-fluorescent rhodamine Schiff base (L) has been isolated in pure form and characterized using spectroscopic and physico-chemical methods with theoretical density functional theory (DFT) support. On addition of Al(III) ions to a solution of L in HEPES buffer (1 mM, pH 7.4; EtOH-water, 1 : 3 v/v) at 25 degrees C, the systematic increase in chelation-enhanced fluorescence (CHEF) enables the detection of Al(III) ions as low as 60 nM with high selectivity, unaffected by the presence of competitive ions. Interestingly, the Al(III) complex (L'-Al; 2) is specifically able to detect fluoride ions by quenching the fluorescence in the presence of large amounts of other anions in the HEPES buffer (1 mM, pH 7.4) at 25 degrees C. On the basis of our experimental and theoretical findings, the addition of Al3+ ions to a solution of L helps to generate a new fluorescence peak at 590 nm, due to the selective binding of Al3+ ions with L in a 1 : 1 ratio with a binding constant (K) of 8.13 x 10(4) M-1. The Schiff base L shows no cytotoxic effect, and it can therefore be employed for determining the intracellular concentration of Al3+ and F-ions by 2 in living cells using fluorescence microscopy.

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大豆是我国最重要的油料作物之一,在我国的农业乃至幽民经济中占有重要地位。但是,由于我国人豆品质较差、产量较低,严重地影响着我国的大豆牛产及其在国际市场上的竞争力。农杆菌介导的转基因方法是大豆改良的最简便和最经济的方法之一,然而大豆基因转化效率低一直是大豆基因工程的主要限制因素。本研究以含有GUS报告基因和NPT II筛选基因的农杆菌1301侵染大豆子叶节和下胚轴,并用组织化学定位法测定GUS基因在叶节和下胚轴上瞬时表达,研究了抗氧化剂对提高大豆基因转化效率的影响,为建立大豆高效基因转化体系奠定基础。 以子叶节为外植体,用农杆菌侵染和共培养后进行GUS染色,观察其瞬时表达情况。在培养基中不含抗氧化剂的情况下,子叶节上未发现染色点,仅在下胚轴侧面有极少染色点。而在培养基巾含有抗氧化剂的情况下,外植体上产生了人量GUS染色点,其中大部分位于下胚轴处,子叶节部位几乎很少被染色。这说明下胚轴比f叶节更容易接受外源基因。本论文分别以子叶节和下胚轴为外植体进行研究。 以子叶节为外植体,在抗氧化剂作用下用农杆菌侵染,诱导丛生芽,在含有潮霉素的筛选培养基上培养,以筛选抗性苗。实验只得到一株抗性幼苗。 为了进一步研究抗氧化剂对GUS暴凶在下胚轴中瞬时表达的影响,我们特别以下胚轴为外植体,测定了多种条件下的瞬时表达率情况。 我们研究了共培养时间对大豆下胚轴基因瞬时表达率的影响,通过确定合适的共培养时间以获得最佳转化率。在共培养2天后,GUS基因的表达率是8%,但是在3天后,GUS基因瞬时表达率大幅度上升,达到23.4%。随后两天GUS基因瞬时表达率没有太大变化,因此,大豆下胚轴的GUS基因瞬时表达的最适共培养时间为3天。 农杆菌再悬浮液稀释浓度对大豆下胚轴GUS基因瞬时表达也有较大影响:再悬浮培养基与农杆菌菌液等体积时,GUS基因瞬时表达率最高,随稀释浓度提高,转化效率降低。这说明随农杆菌菌液浓度提高,侵染几率增加,从而提高了GUS基因的瞬时表达率。 很多研究表明大豆基因转化存在很大的品种问差异,我们选择了四种基因型差异较大的品种在上述最佳条件下分别测定了GUS基因瞬时表达率,但没有发现品种之间存在显著差异,说明抗氧化剂在大豆下胚轴基因转化中具有品种普遍适用性。 上述研究结果表明抗氧化剂能够大大促进GUS基因在下胚轴的瞬时表达,这对于今后开展大豆基因组研究和品质改良工作具有一定意义。

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应用GUS(葡萄糖苷酶 )基因标记技术将标记基因GUS导入受体菌S .fredii8855,标记菌株形成的根瘤可被GUS染色缓冲液染成蓝色 ,而土著菌形成的根瘤不能着色 .由此即可十分简便地确定土著菌的影响程度 .盆栽试验表明 ,S .fredii 8855的结瘤抗酸碱能力高于土著菌 ,能在土壤中较大范围内迁移 .当它的根瘤占有率不小于 43%时 ,接种能显著提高大豆产量 ,大豆产量与根瘤占有率呈正相关 (r=0 .98) ,而与总瘤数关系不大 (r=0 .1 3) .土壤N素显著抑制其结瘤 ,补加P能缓解这种抑制作用 .

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In this study, we chronicle the establishment of a novel transformation system for the unicellular marine green alga, Dunaliella salina. We introduced the CaMV35S promoter-GUS construct into D. saliva with a PDS1000/He micro-particle bombardment system. Forty eight h after transformation, via histochemical staining, we observed the transient expression of GUS in D. salina cells which had been bombarded under rupture-disc pressures of 450 psi and 900 psi. We observed no GUS activity in either the negative or the blank controls. Our findings indicated that the micro-particle bombardment method constituted a feasible approach to the genetic transformation of D. salina. We also conducted tests of the cells' sensitivity to seven antibiotics and one herbicide, and our results suggested that 20 mu g/ ml of Basta could inhibit cell growth completely. The bar gene, which encodes for phosphinothricin acetyltransferase and confers herbicide tolerance, was introduced into the cells via the above established method. The results of PCR and PCR-Southern blot analyses indicated that the gene was successfully integrated into the genome of the transformants.

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本文研究了如何应用GUS基因优化海带表达系统。首先研究了GUS在各种海带材料中的本底值,而后以GUS基因作为报告基因比较了几种基因工程常用启动子在海带中启动瞬间表达的效率。选择表达效率较高的真核藻类启动子与GUS基因融合,在海带中获得了稳定表达的结果。分别用组织化学染色法和荧光分析法对海带雌配子体、雄配子体、孤雌生殖海带幼孢子体和二倍体海带孢子体等四种不同的材料的GUS本底进行了检测到GUS本底。荧光分析法所得数据显示,这四种材料的GUS活性分别为3.4±0.3、5.2±0.8、14.4±1.8、12.5±1.4 (pmol MU mg~(-1) protein min~(-1)),与高等植物类似,说明GUS基因可作为报造基因用于海带基因工程研究。选用真核藻启动子FCP启动子、高等植物基因工程中常用的高效Ubi启动子和CaMV35S启动子,与GUS基因融合构建四种质粒,通过基因松的方法转化孤雌生殖海带幼孢子体,比较GUS基因在海带中的瞬间表达量。实验结果表明,与CaMV35S和FCP融合的GUS基因在海带中表达效率较高。采用基因松的方法用FCP启动子-GUS基因转化海带雌配子体,通过诱导孤雌生殖获得孤雌生殖海带幼孢子体,用组织染色法检测到了GUS活性,并从海带的总DNA扩增到了FCP启动子-GUS基因的特征条带,从而提示了FCP启动子能引导外源基因在海带中稳定表达。为了找寻高效筛选元件进行孤雌生殖海带对草丁膦的敏感性实验,用统计学的方法得出了草丁膦对不同长度孤雌海带的半致死剂量。研究发现海带全长0.5-1.6cm范围内,草丁膦的LD_(50)与海带长度不相关,同时发现浓度在2-5μg/ml狭小范围内的草丁膦对孤雌海带比高浓度具有更为明显的毒性反应。本文结果提示草丁膦抗性基因-bar基因有可能成为海带基因工程更为理想的选择标记,因为海带对草丁膦比对氯霉素和潮霉素更敏感,而后两者是目前采用的筛选压力。本文结果为海带表达系统的优化,提供了有效的报告基因、启动子和选择标记元件。