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21.
Addison PD Neligan PC Ashrafpour H Khan A Zhong A Moses M Forrest CR Pang CY 《American journal of physiology. Heart and circulatory physiology》2003,285(4):H1435-H1443
The aim of this study was to investigate the efficacy and mechanism of action of a noninvasive remote ischemic preconditioning (IPC) technique for the protection of multiple distant skeletal muscles against ischemic necrosis (infarction). It was observed in the pig that three cycles of 10-min occlusion and reperfusion in a hindlimb by tourniquet application reduced the infarction of latissimus dorsi (LD), gracilis (GC), and rectus abdominis (RA) muscle flaps by 55%, 60%, and 55%, respectively, compared with their corresponding control (n = 6, P < 0.01) when they were subsequently subjected to 4 h of ischemia and 48 h of reperfusion. This infarct-protective effect of remote IPC in LD muscle flaps was abolished by an intravenous bolus injection of the nonselective opioid receptor antagonist naloxone (3 mg/kg) 10 min before remote IPC and a continuous intravenous infusion (3 mg/kg) during remote IPC and by an intravenous bolus injection of the selective delta 1-opioid receptor antagonist 7-benzylidenealtrexone maleate (3 mg/kg). However, this infarct-protective effect of remote IPC was not affected by an intravenous bolus injection of the ganglionic blocker hexamethonium chloride (20 mg/kg) or the nonspecific adenosine receptor antagonist 8-(p-sulfophenyl)theophylline (10 mg/kg) or by a local intra-arterial injection of the adenosine1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (3 mg/muscle flap) given 10 min before remote IPC. It was also observed that this remote IPC of skeletal muscle against infarction was associated with a slower rate of muscle ATP depletion during the 4 h of sustained ischemia and a reduced muscle neutrophilic myeloperoxidase activity after 1.5 h of reperfusion. These observations led us to speculate that noninvasive remote IPC by brief cycles of occlusion and reperfusion in a pig hindlimb is effective in global protection of skeletal muscle against infarction. This infarct-protective effect is most likely triggered by the activation of opioid receptors in the skeletal muscle, and remote IPC is associated with an energy-sparing effect during sustained ischemia and attenuation of neutrophil accumulation during reperfusion. 相似文献
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Carl PC Chen Chih-Chin Hsu Wen-Lin Yeh Hsiu-Chu Lin Sen-Yung Hsieh Shih-Cherng Lin Tai-Tzung Chen Max JL Chen Simon FT Tang 《Proteome science》2011,9(1):1-10
Background
Prenatal screening for Down Syndrome (DS) would benefit from an increased number of biomarkers to improve sensitivity and specificity. Improving sensitivity and specificity would decrease the need for potentially risky invasive diagnostic procedures.Results
We have performed an in depth two-dimensional difference gel electrophoresis (2D DIGE) study to identify potential biomarkers. We have used maternal plasma samples obtained from first and second trimesters from mothers carrying DS affected fetuses compared with mothers carrying normal fetuses. Plasma samples were albumin/IgG depleted and expanded pH ranges of pH 4.5 - 5.5, pH 5.3 - 6.5 and pH 6 - 9 were used for two-dimensional gel electrophoresis (2DE). We found no differentially expressed proteins in the first trimester between the two groups. Significant up-regulation of ceruloplasmin, inter-alpha-trypsin inhibitor heavy chain H4, complement proteins C1s subcomponent, C4-A, C5, and C9 and kininogen 1 were detected in the second trimester in maternal plasma samples where a DS affected fetus was being carried. However, ceruloplasmin could not be confirmed as being consistently up-regulated in DS affected pregnancies by Western blotting.Conclusions
Despite the in depth 2DE approach used in this study the results underline the deficiencies of gel-based proteomics for detection of plasma biomarkers. Gel-free approaches may be more productive to increase the number of plasma biomarkers for DS for non-invasive prenatal screening and diagnosis. 相似文献24.
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G. A. Neligan H. Steiner P. S. Gardner J. McQuillin 《BMJ (Clinical research ed.)》1970,3(5715):146-147
In an outbreak of respiratory syncytial (R.S.) virus infection in a maternity hospital the respiratory illness was of a mild nature and the virus was not found in infants without respiratory symptoms. This confirms the suggestion that R.S. virus can infect infants at a very early age. Rapid diagnosis was achieved by applying the direct fluorescent antibody technique to cells in nasal secretions. This proved to be more sensitive than culture techniques where there was delay between the onset of respiratory symptoms and submission of specimens to the laboratory. 相似文献
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P. CIAIS M. WATTENBACH N. VUICHARD P. SMITH S. L. PIAO A. DON S. LUYSSAERT I. A. JANSSENS A. BONDEAU R. DECHOW A. LEIP PC. SMITH C. BEER G. R. VAN DER WERF S. GERVOIS K. VAN OOST E. TOMELLERI A. FREIBAUER E. D. SCHULZE CARBOEUROPE SYNTHESIS TEAM 《Global Change Biology》2010,16(5):1409-1428
We estimated the long‐term carbon balance [net biome production (NBP)] of European (EU‐25) croplands and its component fluxes, over the last two decades. Net primary production (NPP) estimates, from different data sources ranged between 490 and 846 gC m?2 yr?1, and mostly reflect uncertainties in allocation, and in cropland area when using yield statistics. Inventories of soil C change over arable lands may be the most reliable source of information on NBP, but inventories lack full and harmonized coverage of EU‐25. From a compilation of inventories we infer a mean loss of soil C amounting to 17 g m?2 yr?1. In addition, three process‐based models, driven by historical climate and evolving agricultural technology, estimate a small sink of 15 g C m?2 yr?1 or a small source of 7.6 g C m?2 yr?1. Neither the soil C inventory data, nor the process model results support the previous European‐scale NBP estimate by Janssens and colleagues of a large soil C loss of 90 ± 50 gC m?2 yr?1. Discrepancy between measured and modeled NBP is caused by erosion which is not inventoried, and the burning of harvest residues which is not modeled. When correcting the inventory NBP for the erosion flux, and the modeled NBP for agricultural fire losses, the discrepancy is reduced, and cropland NBP ranges between ?8.3 ± 13 and ?13 ± 33 g C m?2 yr?1 from the mean of the models and inventories, respectively. The mean nitrous oxide (N2O) flux estimates ranges between 32 and 37 g C Eq m?2 yr?1, which nearly doubles the CO2 losses. European croplands act as small CH4 sink of 3.3 g C Eq m?2 yr?1. Considering ecosystem CO2, N2O and CH4 fluxes provides for the net greenhouse gas balance a net source of 42–47 g C Eq m?2 yr?1. Intensifying agriculture in Eastern Europe to the same level Western Europe amounts is expected to result in a near doubling of the N2O emissions in Eastern Europe. N2O emissions will then become the main source of concern for the impact of European agriculture on climate. 相似文献
30.
N-Linked glycosylation of a baculovirus-expressed recombinant glycoprotein in insect larvae and tissue culture cells 总被引:2,自引:3,他引:2
The potential of insect cell cultures and larvae infected with recombinant
baculoviruses to produce authentic recombinant glycoproteins cloned from
mammalian sources was investigated. A comparison was made of the N-linked
glycans attached to secreted alkaline phosphatase (SEAP) produced in four
species of insect larvae and their derived cell lines plus one additional
insect cell line and larvae of one additional species. These data survey
N-linked oligosaccharides produced in four families and six genera of the
order Lepidoptera. Recombinant SEAP expressed by recombinant isolates of
Autographa californica and Bombyx mori nucleopolyhedroviruses was purified
from cell culture medium, larval hemolymph or larval homogenates by
phosphate affinity chromatography. The N-linked oligosaccharides were
released with PNGase-F, labeled with 8- aminonaphthalene-1-3-6-trisulfonic
acid, fractionated by polyacrylamide gel electrophoresis, and analyzed by
fluorescence imaging. The oligosaccharide structures were confirmed with
exoglycosidase digestions. Recombinant SEAP produced in cell lines of
Lymantria dispar (IPLB-LdEIta), Heliothis virescens (IPLB-HvT1), and Bombyx
mori (BmN) and larvae of Spodoptera frugiperda, Trichoplusia ni ,
H.virescens , B.mori , and Danaus plexippus contained oligosaccharides that
were structurally identical to the 10 oligosaccharides attached to SEAP
produced in T.ni cell lines. The oligosaccharide structures were all
mannose-terminated. Structures containing two or three mannose residues,
with and without core fucosylation, constituted more than 75% of the
oligosaccharides from the cell culture and larval samples.
相似文献