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921.
Robert A Cross 《BMC biology》2010,8(1):107
Kinesin-14 motor proteins step towards microtubule minus ends, in the opposite direction to other kinesins. Work on the still-enigmatic kinesin-14 mechanism published in BMC Structural Biology shows that the carboxyl terminus of the motor head undergoes a dock-undock cycle, like that of plus-end-directed kinesins. 相似文献
922.
Shigekiyo Matsumoto Chihiro Shingu Hironori Koga Satoshi Hagiwara Hideo Iwasaka Takayuki Noguchi Isao Yokoi 《Neurochemical research》2010,35(7):1010-1016
Electron spin resonance (ESR)-silent ascorbate solutions generate a detectable, likely concentration-dependent signal of ascorbyl
free radicals (AFR) immediately upon addition of a molar excess of dimethyl sulfoxide (DMSO). We aimed to perform quantitative
ESR analysis of AFR in real time after addition of DMSO (AFR/DMSO) to evaluate ascorbate concentrations in fresh hippocampus
or plasma following systemic administration of kainate in mice. Use of a special tissue-type quartz cell allowed immediate
detection of AFR/DMSO ESR spectra in fresh tissues from mice. AFR/DMSO content was increased significantly in fresh hippocampus
or plasma obtained during kainate-induced seizures of mice, reaching maximum levels at 90 min after intraperitoneal administration
of 50 mg/kg kainic acid. This suggests that oxidative injury of the hippocampus resulted from the accumulation of large amounts
of ascorbic acid in the brain after kainic acid administration. AFR/DMSO content measured on an ESR spectrometer can be used
for real-time evaluation of ascorbate content in fresh tissue. Due to the simplicity, good performance, low cost and real-time
monitoring of ascorbate, this method may be applied to clinical research and treatment in the future. 相似文献
923.
Shihong Zhang Yi Wei Huimei Yu Jinliang Liu Hongyu Pan 《Russian Journal of Plant Physiology》2010,57(5):670-675
Most monocotyledons like cereals accumulate antifreeze proteins in the apoplast during cold acclimation, but it is still uncertain
whether dicotyledons do. Here we report the isolation and characterisation of a 33-kD apoplastic chitinase extracted from
the corolla of wintersweet (Chinmonanthus praecox communis L.), which was purified using successive column chromatography on Phenyl-Sepharose, DEAE-Sepharose, and CM-Sepharose. Antifreezing
activity of chitinase was confirmed in terms of the formation of bipyramidal ice crystals and high thermal-hysteresis values.
Interestingly, chitinase was also found to affect germination of fungal spores of four major plant pathogens. From these data,
we hypothesize that, under natural conditions, wintersweet as one of the overwintering dicotyledons also accumulates apoplastic
antifreeze proteins like monocotyledons. To our knowledge, this is the first report on the isolation of dicotyledon apoplastic
chitinase with high-level antifreeze and antifungal activities. 相似文献
924.
925.
Background
All polypeptide backbones have the potential to form amyloid fibrils, which are associated with a number of degenerative disorders. However, the likelihood that amyloidosis would actually occur under physiological conditions depends largely on the amino acid composition of a protein. We explore using a naive Bayesian classifier and a weighted decision tree for predicting the amyloidogenicity of immunoglobulin sequences. 相似文献926.
927.
Hermes copper butterfly (Lycaena [Hermelycaena] hermes) is a rare species inhabiting the coastal sage scrub adjacent to San Diego, CA USA. Conservation groups and wildlife agencies
recognize this species is threatened by habitat loss due to urbanization and recent wildfires extirpating local populations.
To assess the status of the Hermes copper, we summarize the literature concerning taxonomy, distribution, and ecology, as
well as present original distributional and ecological data. Adults were sampled by presence/absence surveys, Pollard Walks,
and mark-release-recapture. The current distribution is reduced from historic ranges, specifically in extreme southern and
northern San Diego County. Recent wildfires in 2003 and 2007 led to the extirpation of many populations, with only one post-fire
recolonization documented. Adult emergence dates ranged from mid-May to early June, while densities varied from five to nine-fold
among years based on peak abundance and mark-release-recapture estimates, respectively. We observed significantly more males;
most were territorial and exhibit a relatively sedentary behavior. The median dispersal range was 25.8 and 11.3 m, and the
median minimum distance traveled was 34.4 and 17.6 m at Rancho Jamul Ecological Reserve and Hollenbeck Canyon Wildlife Area,
respectively. The longest recorded movement by an individual was 1,132.0 m. Post-fire habitat recovery and the ability to
move across the landscape are essential for the Hermes copper to persist in an increasingly dynamic and fragmented coastal
sage scrub habitat. Therefore, we need to develop a better understanding of habitat requirements and connectivity of populations
for the long-term management and conservation of this species. 相似文献
928.
TNF inhibitors are currently considered both effective and cost-effective in patients with active rheumatoid arthritis (RA), particularly in patients who have not responded fully to methotrexate. There is substantial doubt about the cost-effectiveness of TNF inhibitors as initial treatment for active RA. New data from the National Data Bank for Rheumatic Diseases now question the current consensus in methotrexate failures. The data suggest that in routine clinical practice TNF inhibitors provide only modest incremental benefits over best conventional therapy. If confirmed, these observational studies suggest that the economic argument underpinning the widespread use of TNF inhibitors in established RA is unsustainable. 相似文献
929.
Koichi Murata Hiroyuki Yoshitomi Shimei Tanida Masahiro Ishikawa Kohei Nishitani Hiromu Ito Takashi Nakamura 《Arthritis research & therapy》2010,12(3):R86
Introduction
MicroRNAs (miRNAs), endogenous small noncoding RNAs regulating the activities of target mRNAs and cellular processes, are present in human plasma in a stable form. In this study, we investigated whether miRNAs are also stably present in synovial fluids and whether plasma and synovial fluid miRNAs could be biomarkers of rheumatoid arthritis (RA) and osteoarthritis (OA). 相似文献930.