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331.
Microarray-based gene expression analysis plays a pivotal role in modern biology and is poised to enter the field of molecular diagnostics. Current microarray-based gene expression systems typically require enzymatic conversion of mRNA into labeled cDNA or cRNA. Conversion to cRNA involves a target amplification step that overcomes the low sensitivity associated with commonly used fluorescent detection methods. Herein, we present a novel enzyme-free, microarray-based gene expression system that uses unamplified total human RNA sample as the target nucleic acid. The detection of microarray-bound RNA molecules is accomplished by targeting the poly-A tail with an oligo-dT20 modified gold nanoparticle probe, signal amplification by autometallography, and subsequent measurement of nanoparticle-mediated light scattering. The high sensitivity afforded by the nanoparticle probes allows differential gene expression from as little as 0.5 μg unamplified total human RNA in a 2 h hybridization without the need for elaborate sample labeling steps.  相似文献   
332.
In order to ascertain the molecular basis of ATP-mediated drug extrusion by Cdr1p, a multidrug transporter of Candida albicans, we recently have reported that the Walker A motif of the N-terminal nucleotide biding domain (NBD) of this protein contains an uncommon cysteine residue (C193; GXXGXGCS/T) which is indispensable for ATP hydrolysis. This residue is exceptionally conserved in N-terminal NBDs of fungal ABC transporters and hence makes these transporters an evolutionarily divergent group. However, the presence of a conventional lysine residue at a similar position in the Walker A motif of the C-terminal NBD warrants the individual contribution of both the NBDs in the ATP-driven efflux function of such transporters. In this study we have investigated the contribution of this divergent Walker A motif in the context of the full Cdr1p protein under in vivo conditions by swapping these two crucial amino acids (C193K in Walker A motif of N-terminal NBD and K901C in Walker A motif of C-terminal NBD) between the two NBDs. Both the native and the mutant variants of Cdr1p were integrated at the PDR5 locus as GFP-tagged fusion proteins and were hyper-expressed. Our study shows that both C193K- and K901C-expressing cells elicit a severe impairment of Cdr1p's ATPase function. However, both these mutations have distinct phenotypes with respect to other functional parameters such as substrate efflux and drug resistance profiles. In contrast to C193K, K901C mutant cells were substantially hypersensitive to the tested drugs (fluconazole, ansiomycin, miconazole and cycloheximide) and were unable to expel rhodamine 6G. Our results for the first time show that both NBDs influence the Cdr1p function asymmetrically, and that the positioning of the cysteine and lysine residues within the respective Walker A motifs is functionally not interchangeable.  相似文献   
333.
The Rvb1p and Rvb2p (or TIP48 and TIP49) nuclear ATP binding proteins are universally conserved in eukaryotes and essential for viability of yeasts. Rvbp associate with each other as a double hexamer, with YHR034c and with two complexes involved in chromatin remodeling, Ino80.com and Swr1.com. Loss of Rvb1p or Ino80p affects many yeast promoters similarly. Rvbp are not essential for the recruitment of Ino80p to promoters but are essential for the catalytic activity of Ino80.com. Loss of Rvbp leads to loss of the functionally critical Arp5p in Ino80.com. Rvb2p associates with Arp5p in vitro in a reaction dependent on the presence of ATP and Ino80p. Therefore, Rvbp are required for the structural and functional integrity of the Ino80 chromatin remodeling complex.  相似文献   
334.
335.
Length–weight relationships (LWRs) are presented for 11 deep‐sea fishes caught in the western Bay of Bengal and Andaman waters during August 2010 using a 38 m high speed demersal trawl II (HSDT II, crustacean version, codend mesh size 40 mm) and a 45.6 m Expo model demersal trawl (codend mesh size 30 mm). The b values ranged from 2.34 to 3.3 and the coefficient of variation (r2) ranged from .82 to .98. LWR estimates of eight deep‐sea fishes are provided for the first time. The estimated LWR values were compared with the Bayesian LWR estimates available in FishBase, based on models developed to improve the accuracy and predictability of species‐specific growth parameters of data‐poor species.  相似文献   
336.
Adenine and pyridine nucleotides play vital roles in virtually all aspects of plant growth. This study analyzed the response of adenine and pyridine metabolism during germination and early seedling growth (ESG) of Brassica juncea exposed to two doses of arsenate (AsV), 100 and 250 μM, having non-significant or significant inhibitory effects, respectively, on germination and ESG. The ratio of NAD/NADP and NAD/NADH showed no significant change in control and 100 μM AsV, but increased significantly at 250 μM AsV during initial 24 h and also at 7th day. The activity of enzymes of NAD metabolism, viz. NAD kinase, NADP phosphatase, nicotinamidase and poly(ADP-ribose) polymerases showed significant change mostly at 250 μM AsV. Further, significant decrease was observed in the ratio of ATP/ADP and in the activities of adenylate kinase and apyrase at 250 μM AsV at 7th day. External supply of ATP (1 mM) to 100 and 250 μM AsV significantly improved germination percentage and germination strength of the seeds as compared to AsV treatments alone. The study concludes that with the increase in concentration of AsV, the balance of NAD/NADP, NAD/NADH and ATP/ADP and the activities of enzymes of adenine and pyridine metabolism were significantly altered and that these changes may be responsible for inhibitory effects of AsV on germination and ESG.  相似文献   
337.
This article reports on the optical properties of 0.5% mol of Sm3+, Dy3+ ion‐doped B2O3‐TeO2‐Li2O‐AlF3 (LiAlFBT) glasses. The glass samples were characterized by optical absorption and emission spectra. Judd‐Ofelt theory was applied to analyze the optical absorption spectra and calculate the intensity parameters and radiative properties of the emission transitions. The emission spectra of Sm3+ and Dy3+:LiAlFBT glasses showed a bright reddish‐orange emission at 598 nm (4G5/26H7/2) and an intense yellow emission at 574 nm (4F9/26H13/2), respectively. Full width at half maximum (FWHM), stimulated emission cross section, gain bandwidth and optical gain values were also calculated to extend the applications of the Sm3+ and Dy3+:LiAlFBT glasses. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
338.
A simple, sensitive, and robust normal‐phase isocratic HPLC‐UV method was developed and validated for the enantiomeric separation of rasagiline mesylate and its (S)‐enantiomer. The rasagiline and its (S)‐enantiomer were resolved on a Chiralcel‐OJ‐H (4‐methylbenzoate cellulose coated on silica) column using a mobile phase consisting of n‐hexane:isopropyl alcohol:ethanol:diethyl amine (96:2:2:0.01) at a flow rate of 1.0 ml/min. The column temperature was maintained at 27 °C and elution was monitored at 215 nm. The resolution (Rs) between the enantiomers was found to be more than 2.0. The limit of detection and the limit of quantification of the (S)‐enantiomer were found to be 0.35 and 1.05 µg/ml, respectively. The developed method was validated as per ICH guidelines with respect to linearity, limit of detection and quantification, accuracy, precision, and robustness—and satisfactory results were obtained. The sample solution and mobile phase were found to be stable up to 48 h. The method is useful for routine evaluation of the quality of rasagiline mesylate in bulk drug‐manufacturing units. Chirality 25:324–327, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
339.
Molecular identification of microalgal species is vital and involves sequencing of specific markers present in the genome, which are unique to a genus. PCR is a vital tool for identification of microalgae; the preparation of template DNA for PCR by traditional methods requires large amount of algal cells and a time-consuming process. One simple way to reduce these complications is to use the microalgal colonies directly for amplification of required DNA fragments from the genome. In this study, a simple cell-disrupting method, using autoclaved glass powder, has been used for direct colony PCR of microalgae. Four morphologically different microalgal strains were chosen from freshwater samples, and the PCR amplification reaction was evaluated with three different molecular markers (rbcL, internal transcribed spacer 2, and 18S rDNA). PCR amplification was optimized with less number of cells (0.04?×?105), minimal quantity of glass powder (0.5 mg), and in the presence of Milli-Q water for internal transcribed spacer marker. The isolated strains were identified as Desmodesmus sp. JQ782747, Coelastrum proboscideum JQ898144, Chlorella sorokiniana JQ898145, and Scenedesmus sp. JQ782746 based on sequence similarity. This direct microalgal colony PCR proves to be a simple and rapid method for detection of varied microalgal species.  相似文献   
340.

Object

Antiangiogenic treatments are beginning to give promising outcomes in many vascular diseases including tumor angiogenesis. In this current study the antiangiogenic and pro-apoptotic actions of α1(IV)NC1 and its N- and C- peptides α1S1(IV)NC1, α1S2(IV)NC1 were investigated in-vitro and in-vivo.

Study Method

Endothelial cells (ECs) were treated with α1(IV)NC1, α1S1(IV)NC1, α1S2(IV)NC1 and in-vitro proliferation, migration, tube formation and apoptotic assays were executed. FasL, Fas, Caspase-8, -3 and PARP activations were studied using immunoblotting analysis using specific antibodies. Also the in-vivo antiangiogenic and pro-apoptotic effects were tested using α1(IV)NC1 in a mice model.

Results

Like α1(IV)NC1, its N- and C- terminal α1S2(IV)NC1 and α1S1(IV)NC1 domains posses anti-proliferative, pro-apoptotic activity and inhibit ECs migration and tube formation in-vitro. Both α1S1(IV)NC1 and α1S2(IV)NC1 domains promote apoptosis by activating FasL and down stream apoptotic events including activation of caspase-8, -3 and PARP cleavage in a dose dependent manner in-vitro in ECs. Tumors in mice showed apoptotic TUNEL positive microvasculature upon α1(IV)NC1 treatment, indicating inhibition of tumor angiogenesis and tumor growth. Further, the antitumor activity of α1(IV)NC1 was abrogated when caspase-3 inhibitor was used. These results conform additional properties of α1(IV)NC1 as an endogenous angioinhibitor that induces apoptosis in-vitro and in-vivo by activating FasL mediated caspase-3.

Significance

α1(IV)NC1 and its N- and C- terminal α1S1(IV)NC1 and α1S2(IV)NC1 domains also posses pro-apoptotic and angioinhibitory activity in-vitro and in-vivo. α1(IV)NC1 regulates tumor angiogenesis by activating FasL mediated apoptosis in-vitro and in-vivo. These results demonstrate that α1(IV)NC1 and its peptides inhibit neo-vascular diseases.  相似文献   
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