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151.
Piotr Chomczynski William W. Wilfinger Hamid R. Eghbalnia Amy Kennedy Michal Rymaszewski Karol Mackey 《PloS one》2016,11(2)
Relatively little is known about the range of RNA levels in human blood. This report provides assessment of peripheral blood RNA level and its inter-individual differences in a group of 35 healthy humans consisting of 25 females and 10 males ranging in age from 50 to 89 years. In this group, the average total RNA level was 14.59 μg/ml of blood, with no statistically significant difference between females and males. The individual RNA level ranged from 6.7 to 22.7 μg/ml of blood. In healthy subjects, the repeated sampling of an individual’s blood showed that RNA level, whether high or low, was stable. The inter-individual differences in RNA level in blood can be attributed to both, differences in cell number and the amount of RNA per cell. The 3.4-fold range of inter-individual differences in total RNA levels, documented herein, should be taken into account when evaluating the results of quantitative RT-PCR and/or RNA sequencing studies of human blood. Based on the presented results, a comprehensive assessment of gene expression in blood should involve determination of both the amount of mRNA per unit of total RNA (U / ng RNA) and the amount of mRNA per unit of blood (U / ml blood) to assure a thorough interpretation of physiological or pathological relevance of study results. 相似文献
152.
Bouwer JC Mackey MR Lawrence A Deerinck TJ Jones YZ Terada M Martone ME Peltier S Ellisman MH 《Journal of structural biology》2004,148(3):297-306
We describe the technique and application of energy filtering, automated most-probable loss (MPL) tomography to intermediate voltage electron microscopy (IVEM). We show that for thick, selectively stained biological specimens, this method produces a dramatic increase in resolution of the projections and the computed volumes versus standard unfiltered transmission electron microscopy (TEM) methods. This improvement in resolution is attributed to the reduction of chromatic aberration, which results from the large percentage of inelastic electron-scattering events for thick specimens. These improvements are particularly evident at the large tilt angles required to improve tomographic resolution in the z-direction. This method effectively increases the usable thickness of selectively stained samples that can be imaged at a given accelerating voltage by dramatically improving resolution versus unfiltered TEM and increasing signal-to-noise versus zero-loss imaging, thereby expanding the utility of the IVEM to deliver information from within specimens up to 3 microm thick. 相似文献
153.
This two-part study compared the efficacy of different plant species to extract Se from soils irrigated with Se-laden effluent. The species used were: Brassica napus L. (canola), Brassica juncea Czern L. and Coss (Indian mustard), and Hordeum vulgare L. (barley). In Study 1 we irrigated the plants with a saline effluent containing 0.150 mg Se L–1, while in Study 2, the same species were planted in a saline soil selenized with 2 mg Se L–1. Plants were simultaneously harvested 120 days after planting. In Study 1, there were only slight effects of treatment on dry matter (DM) yield. Plant Se concentrations averaged 21 g Se g–1DM for the Brassica species, and 4.0 g Se g–1 DM for barley. Total Se added to soils via effluent decreased by 40% for Brassica species and by 20% for barley. In Study 2, total DM decreased for all species grown in saline soils containing Se. Plant Se concentrations averaged 75 g g–1 DM for Brassica species and 12 g Se g–1 DM for barley. Total Se added to soils prior to planting decreased by 40% for Brassica species and up to 12% for barley. In both studies, plant accumulation of Se accounted for at least 50% of the Se removed in soils planted to Brassica and up to 20% in soils planted to barley. Results show that although the tested Brassica species led to a significant reduction in Se added to soil via use of Se-laden effluent, additional plantings are necessary to further decrease Se content in the soil. 相似文献
154.
Sianos G Kay IP Carlier SG Lighart JM Wardeh AJ Coen VL Levendag PC Serruys PW 《International journal of cardiovascular interventions》2000,3(2):121-125
The application of beta-radiation in coronary arteries is a promising new technique for the treatment of in-stent restenosis. This is the first case in which the 5 F. delivery catheter of the Beta-Cath trade mark system was advanced through the struts of a stent, previously deployed in an adjacent branch, so as to deliver radiation to the target vessel. 相似文献
155.
Two Pseudomonas syringae type III effectors inhibit RIN4-regulated basal defense in Arabidopsis 总被引:1,自引:0,他引:1
Plant cells have two defense systems that detect bacterial pathogens. One is a basal defense system that recognizes complex pathogen-associated molecular patterns (PAMPs). A second system uses disease-resistance (R) proteins to recognize type lll effector proteins that are delivered into the plant cell by the pathogen's type III secretion system. Here we show that these two pathways are linked. We find that two Pseudomonas syringae type III effectors, AvrRpt2 and AvrRpm1, inhibit PAMP-induced signaling and thus compromise the host's basal defense system. RIN4 is an Arabidopsis protein targeted by AvrRpt2 and AvrRpm1 for degradation and phosphorylation, respectively. We find that RIN4 is itself a regulator of PAMP signaling. The R proteins, RPS2 and RPM1, sense type III effector-induced perturbations of RIN4. Thus, R proteins guard the plant against type III effectors that inhibit PAMP signaling and provide a mechanistic link between the two plant defense systems. 相似文献
156.
Conjugation of lentivirus to paramagnetic particles via nonviral proteins allows efficient concentration and infection of primary acute myeloid leukemia cells
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Chan L Nesbeth D Mackey T Galea-Lauri J Gäken J Martin F Collins M Mufti G Farzaneh F Darling D 《Journal of virology》2005,79(20):13190-13194
Nonviral producer cell proteins incorporated into retroviral vector surfaces profoundly influence infectivity and in vivo half-life. We report the purification and concentration of lentiviral vectors using these surface proteins as an efficient gene transduction strategy. Biotinylation of these proteins and streptavidin paramagnetic particle concentration enhances titer 400- to 2,500-fold (to 10(9) CFU/ml for vesicular stomatitis virus G protein and 5 x 10(8) for amphotropic murine leukemia virus envelope). This method also uses newly introduced membrane proteins (B7.1 and DeltaLNGFR) directed to lentiviral surfaces, allowing up to 17,000-fold concentrations. Particle conjugation of lentivirus allows facile manipulation in vitro, resulting in the transduction of 48 to 94% of human acute myeloid leukemia blasts. 相似文献
157.
Amulet C-L (cue-lure) and Amulet ME (methyl eugenol) molded paper fiber "attract-and-kill" dispensers containing fipronil were tested under Hawaiian weather conditions against Bactrocera cucurbitae (Coquillett) (melon fly) and Bactrocera dorsalis (Hendel) (oriental fruit fly), respectively. In paired tests (fresh versus weathered), C-L dispensers were effective for at least 77 d, whereas ME dispensers were effective for at least 21 d. Thus, C-L dispensers exceeded, whereas ME dispensers did not meet the label interval replacement recommendation of 60 d. Addition of 4 ml of ME to 56-d-old ME dispensers restored attraction and kill for an additional 21 d. This result suggested the fipronil added at manufacture was still effective. By enclosing and weathering ME dispensers inside small plastic bucket traps, longevity of ME dispensers was extended up to 56 d. Fipronil ME and C-L dispensers also were compared, inside bucket traps, to other toxicants: spinosad, naled, DDVP, malathion, and permethrin. Against B. dorsalis, fipronil ME dispensers compared favorably only up to 3 wk. Against B. cucurbitae, fipronil C-L dispensers compared favorably for at least 15 wk. Our results suggest that fipronil C-L dispensers can potentially be used in Hawaii; however, fipronil ME dispensers need to be modified or protected from the effects of weathering to extend longevity and meet label specifications. Nonetheless, Amulet C-L and ME dispensers are novel prepackaged formulations containing C-L or ME and fipronil that are more convenient and safer to handle than current liquid insecticide formulations used for areawide suppression of B. dorsalis and B. cucurbitae in Hawaii. 相似文献
158.
Jo?o?Luiz?S?Moreira Rodrigo?M?Mota Maria?F?Horta Santuza?MR?Teixeira Elisabeth?Neumann Jacques?R?Nicoli álvaro?C?NunesEmail author 《BMC microbiology》2005,5(1):15
Background
The accurate identification of Lactobacillus and other co-isolated bacteria during microbial ecological studies of ecosystems such as the human or animal intestinal tracts and food products is a hard task by phenotypic methods requiring additional tests such as protein and/or lipids profiling. 相似文献159.
Mlikota Gabler F Mansour MF Smilanick JL Mackey BE 《Journal of applied microbiology》2004,96(6):1354-1360
AIMS: To quantify and model the toxicity of brief exposures of spores of Rhizopus stolonifer, Aspergillus niger, Botrytis cinerea and Alternaria alternata to heated, aqueous ethanol solutions. These fungi are common postharvest decay pathogens of fresh grapes and other produce. Sanitation of produce reduces postharvest losses caused by these and other pathogens. METHODS AND RESULTS: Spores of the fungi were exposed to solutions containing up to 30% (v/v) ethanol at 25-50 degrees C for 30 s, then their survival was determined by germination on semisolid media. Logistical, second-order surface-response models were prepared for each fungus. Subinhibitory ethanol concentrations at ambient temperatures became inhibitory when heated at temperatures much lower than those that cause thermal destruction of the spores by water alone. At 40 degrees C, the estimated ethanol concentrations that inhibited the germination of 50% (LD(50)) of the spores of B. cinerea, A. alternata, A. niger and R. stolonifer were 9.7, 13.5, 19.6 and 20.6%, respectively. CONCLUSIONS: Ethanol and heat combinations were synergistic. Control of spores of these fungi could be accomplished with much lower temperatures and ethanol concentrations when combined compared with either used alone. Botrytis cinerea and A. alternata were less resistant to the combination than A. niger or R. stolonifer. 相似文献
160.
An obligatory step in the mammalian nutritional utilization of pyridoxine-5'-beta-D-glucoside (PNG) is the intestinal hydrolysis of its beta-glucosidic bond that releases pyridoxine (PN). This laboratory previously reported the purification and partial characterization of a novel cytosolic enzyme, designated PNG hydrolase, which hydrolyzed PNG. An investigation of the subcellular distribution of intestinal PNG hydrolysis found substantial hydrolytic activity in the total membrane fraction, of which 40-50% was localized to brush border membrane. To investigate the possible role of a brush border beta-glucosidase in the hydrolysis of PNG, lactase phlorizin hydrolase (LPH) was purified from rat small intestinal mucosa. LPH hydrolyzed PNG with a K(m) of 1.0 +/- 0.1 mm, a V(max) of 0.11 +/- 0.01 micromol/min.mg protein, and a k(cat) of 1.0 s(-1). LPH-catalyzed PNG hydrolysis was inhibited by glucose, lactose, and cellobiose but not by PN. Specific blockage of the phlorizin hydrolase site of LPH using 2',4'-dintrophenyl-2-fluoro-2-deoxy-beta-D-glucopyranoside did not reduce PNG hydrolysis. Evidence of transferase activity was also obtained. Reaction mixtures containing LPH, PNG, and lactose yielded the formation of another PN derivative that was identified as a pyridoxine disaccharide. These results indicate that LPH may play an important role in the bioavailability of PNG, but further characterization is needed to assess its physiological function. 相似文献