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131.
HIF-1 expression in healing wounds: HIF-1alpha induction in primary inflammatory cells by TNF-alpha 总被引:12,自引:0,他引:12
132.
Copper- and arsenate-induced oxidative stress in Holcus lanatus L. clones with differential sensitivity 总被引:5,自引:0,他引:5
The biochemical responses of Holcus lanatus L. to copper and arsenate exposure were investigated in arsenate‐tolerant and ‐non‐tolerant plants from uncontaminated and arsenic/copper‐contaminated sites. Increases in lipid peroxidation, superoxide dismutase (SOD) activity and phytochelatin (PC) production were correlated with increasing copper and arsenate exposure. In addition, significant differences in biochemical responses were observed between arsenate‐tolerant and ‐non‐tolerant plants. Copper and arsenate exposure led to the production of reactive oxygen species, resulting in significant lipid peroxidation in non‐tolerant plants. However, SOD activity was suppressed upon metal exposure, possibly due to interference with metallo‐enzymes. It was concluded that in non‐tolerant plants, rapid arsenate influx resulted in PC production, glutathione depletion and lipid peroxidation. This process would also occur in tolerant plants, but by decreasing the rate of influx, they were able to maintain their constitutive functions, detoxify the metals though PC production and quench reactive oxygen species by SOD activity. 相似文献
133.
134.
As part of systematic studies of the genus Porphyrain New Zealand, constituent sugar analyses of cell wall polysaccharidesin situ in dry thalli were found to yield data that weretaxonomically informative. Variation in constituent sugar levels betweenspecieswas sufficient in some cases to be useful in species differentiation. Thereproductive state of thallus regions had a significant impact on the levels ofconstituent sugars, whereas storage of dried thalli for eight months had noeffect. Three epiphytic taxa currently classified as species ofPorphyra appear to be incorrectly placed within the genus,as their constituent sugars and the levels of these sugars differed markedlyfrom those of all other species examined. 相似文献
135.
Maria Rebelo Claudia Sousa Howard M. Shapiro Maria M. Mota Martin P. Grobusch Thomas H?nscheid 《PloS one》2013,8(4)
Resistance of Plasmodium falciparum to almost all antimalarial drugs, including the first-line treatment with artemisinins, has been described, representing an obvious threat to malaria control. In vitro antimalarial sensitivity testing is crucial to detect and monitor drug resistance. Current assays have been successfully used to detect drug effects on parasites. However, they have some limitations, such as the use of radioactive or expensive reagents or long incubation times. Here we describe a novel assay to detect antimalarial drug effects, based on flow cytometric detection of hemozoin (Hz), which is rapid and does not require any additional reagents. Hz is an optimal parasite maturation indicator since its amount increases as the parasite matures. Due to its physical property of birefringence, Hz depolarizes light, hence it can be detected using optical methods such as flow cytometry. A common flow cytometer was adapted to detect light depolarization caused by Hz. Synchronized in vitro cultures of P. falciparum were incubated for 48 hours with several antimalarial drugs. Analysis of depolarizing events, corresponding to parasitized red blood cells containing Hz, allowed the detection of parasite maturation. Moreover, chloroquine resistance and the inhibitory effect of all antimalarial drugs tested, except for pyrimethamine, could be determined as early as 18 to 24 hours of incubation. At 24 hours incubation, 50% inhibitory concentrations (IC50) were comparable to previously reported values. These results indicate that the reagent-free, real-time Hz detection assay could become a novel assay for the detection of drug effects on Plasmodium falciparum. 相似文献
136.
Abstract Brassica rupestris Raf. is a chasmophyte species that includes two subspecies, both endemic to Central-Western Sicily (Italy). Inter-Simple Sequence Repeat (ISSR) markers were used to detect genetic diversity within and among eight populations representative of the species' distribution range. High levels of genetic diversity were revealed both at the population (PPB = 53.88%, H S = 0.212, Sh = 0.309) and at the species level (PPB = 96.55%, H T = 0.307, Sh = 0.464). The correlation between genetic and geographical distances was negative (Mantel test, r = ?0.06, P < 0.95). The two subspecies of B. rupestris, subsp. rupestris and subsp. hispida, showed remarkable genetic similarity and molecular data did not unequivocally support their distinctness. The pattern of genetic variation revealed by our study bears important consequences for conservation management: It is desirable to preserve B. rupestris populations in situ with a “dynamic” strategy, while, ex situ conservation programmes might be improved to safeguard maximum genetic diversity. 相似文献
137.
138.
Rigorous extraction methods coupled with capillary gel electrophoresis (CGE) provide a basis for a nonradiolabel assay for quantitation of intact antisense drug and its numerous chain-shortened metabolites. As part of the validation of the CGE method, we compared the quantitation of unlabeled ISIS 3521 (ISI 641A) and its chain-shortened metabolites with total radioactivity of [(35)S]-ISIS 3521. ISIS 3521 was labeled on the fifth nucleotide linkage from the 5'-end with (35)S by well-established methods. Multiple tissues collected from rats after administration of [(35)S]-ISIS 3521 were assayed by both radiolabel (liquid scintillation spectroscopy) and CGE methods. The CGE method provided accurate quantitation of the drug and its metabolites in kidney cortex and liver tissues. The correlation between methods for multiple tissues over time was excellent with 88.5% of the measurements being statistically equivalent. These data suggest that CGE is an accurate means of quantitating oligonucleotide in tissue and that it compares favorably with traditional radiochemical techniques. Clearance half-lives for total measurable oligonucleotides were equivalent to clearance of total radioactivity in both liver and kidney with the longest clearance half-life associated with the kidney. 相似文献
139.
Ramakrishna A. Bangaru Yatish K. Bansal A. R. M. Rao T. P. Gandhi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2000,739(2)
A rapid, simple and sensitive reversed-phase high-performance liquid chromatographic (HPLC) method has been developed for the measurement of acyclovir concentrations in human plasma and its use in bioavailability studies is evaluated. Unchanged acyclovir has been quantified without the introduction of an internal standard using the present method. Human plasma proteins were selectively precipitated by the addition of 7% perchloric acid to spiked plasma samples or to the plasma samples obtained after acyclovir administration to human volunteers and the mixture was spun at 1000 g for 10 min. The supernatant was directly injected into a Novaflex C18 column and detected at 254 nm. The mobile phase consisted of octane sulfonic acid buffer (pH 2.5) and methanol (92:08). The limit of quantitation for acyclovir in plasma was 20 ng/ml, which enabled the determination of the area under the curve (AUC) more precisely, that is, it is much closer to its extrapolated value. The present method has been successfully applied to samples from bioavailability studies. 相似文献
140.
M. A. Riddin G. J. Venter K. Labuschagne M. H. Villet 《Medical and veterinary entomology》2019,33(4):467-475
An upsurge in African horse sickness (AHS) in the Eastern Cape, South Africa, from 2006 led to an epidemiological reassessment of the disease there. Light trapping surveys carried out near horses, donkeys and zebras in 2014–2016 collected 39 species of Culicoides midge (Diptera: Ceratopogonidae) that are potential vectors of AHS. To establish if these midges fed on equids, DNA sequences were obtained from the gut contents of 52 female midges (35 freshly blood‐fed, 13 gravid and four parous), representing 11 species collected across 11 sites. Culicoides leucostictus fed on all three equids. Culicoides bolitinos, Culicoides imicola and Culicoides magnus fed on both horses and donkeys. Culicoides onderstepoortensis fed on donkeys, and Culicoides similis and Culicoides pycnostictus fed on zebras. Bloodmeals from cows, pigs, warthogs, impalas and a domestic dog were also identified in various species, but none of the midges tested had fed on birds. These results contribute to knowledge of the vectorial capacity of several species of Culicoides with regard to AHS in the Eastern Cape and point to potential reservoir hosts, of which donkeys, zebras and domestic dogs have previously been found to harbour AHS. Blood‐fed midges were also obtained throughout winter, indicating the potential for endemic AHS in the province. 相似文献