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731.
Evidence suggests the NADPH oxidases contribute to ischaemic stroke injury and Nox2 is the most widely studied subtype in the context of stroke. There is still conjecture however regarding the benefits of inhibiting Nox2 to improve stroke outcome. The current study aimed to examine the temporal effects of genetic Nox2 deletion on neuronal loss after ischaemic stroke using knockout (KO) mice with 6, 24 and 72 hour recovery. Transient cerebral ischaemia was induced via intraluminal filament occlusion and resulted in reduced infarct volumes in Nox2 KO mice at 24 h post-stroke compared to wild-type controls. No protection was evident at either 6 h or 72 h post-stroke, with both genotypes exhibiting similar volumes of damage. Reactive oxygen species were detected using dihydroethidium and were co-localised with neurons and microglia in both genotypes using immunofluorescent double-labelling. The effect of Nox2 deletion on vascular damage and recovery was also examined 24 h and 72 h post-stroke using an antibody against laminin. Blood vessel density was decreased in the ischaemic core of both genotypes 24 h post-stroke and returned to pre-stroke levels only in Nox2 KO mice by 72 h. Overall, these results are the first to show that genetic Nox2 deletion merely delays the progression of neuronal loss after stroke but does not prevent it. Additionally, we show for the first time that Nox2 deletion increases re-vascularisation of the damaged brain by 72 h, which may be important in promoting endogenous brain repair mechanisms that rely on re-vascularisation. 相似文献
732.
733.
734.
William S. McCann 《The Western journal of medicine》1952,77(5):315-318
Perfect coordination is required between the amount of air breathed to ventilate the air cells of the lungs and the amount of blood pumped through them by the heart.Over-ventilation often accompanies severe emotional disturbances with far-reaching effects on the functions of the brain and other organs. Of particular interest are the effects of altering breathing upon angina pectoris.In conditions with under-ventilation the effects are serious because the carbon dioxide which accumulates acts as a narcotic on the nerve centers which control breathing. If oxygen is given to such patients they may be made much worse and become unconscious. Morphine and other narcotics also make matters worse.Under-ventilation in patients with over-distention of the air cells of the lungs results in a chronic form of carbon dioxide poisoning, so that the lungs may fail in ventilatory function. Recent work by Whittenberger has shown how to combat this situation by mechanical over-ventilation. As the excess of carbonic acid is removed the narcotic effect of the gas is lessened and the nerve center governing breathing resumes more normal operation under which the effect of oxygen is no longer deleterious. 相似文献
735.
Designing the deconstruction of plant cell walls 总被引:2,自引:0,他引:2
Cell wall architecture plays a key role in the regulation of plant cell growth and differentiation into specific cell types. Gaining genetic control of the amount, composition, and structure of cell walls in different cell types will impact both the quantity and yield of fermentable sugars from biomass for biofuels production. The recalcitrance of plant biomass to degradation is a function of how polymers crosslink and aggregate within walls. Novel imaging technologies provide an opportunity to probe these higher order structures in their native state. If cell walls are to be efficiently deconstructed enzymatically to release fermentable sugars, then we require a detailed understanding of their structural organization in future bioenergy crops. 相似文献
736.
F. J. McCann 《BMJ (Clinical research ed.)》1922,1(3185):77-78
737.
Cloning and expression of the cDNA coding for aequorin, a bioluminescent calcium-binding protein 总被引:8,自引:0,他引:8
D Prasher R O McCann M J Cormier 《Biochemical and biophysical research communications》1985,126(3):1259-1268
Aequorin is a bioluminescent protein which consists of a polypeptide chain (apoaequorin), coelenterate luciferin, and bound oxygen. Aequorin produces blue light upon binding Ca2+. We have isolated six recombinant pBR322 plasmids which contain apoaequorin cDNA sequences. A mixed synthetic pBR322 plasmids which contain apoaequorin cDNA sequences. A mixed synthetic oligonucleotide probe was used to identify these cDNAs. An extract of an E. coli strain possessing the largest cDNA contained apoaequorin. This apoaequorin can be converted to aequorin in the presence of coelenterate luciferin, 2-mercaptoethanol, and O2. This cDNA is therefore apparently full-length. 相似文献
738.
Methysergide administered i.p. caused a dose dependent decrease of serum prolactin levels in rats of both sexes bearing large bilateral electrolytic lesions in the median eminence. This prolactin release inhibiting action of methysergide was prevented by pretreatment of the animals with dopamine receptor blockers pimozide or spiroperidol, which by themselves had no effect on serum prolactin levels. Similar results were observed when the dopamine receptor agonist piribedil was used instead of methysergide. It is concluded that methysergide is capable of inhibiting prolactin secretion by activation of dopamine receptors of the pituitary lactotrophs. 相似文献
739.
S. Gollasch H. Rosenthal H. Botnen M. Crncevic M. Gilbert J. Hamer N. Hülsmann C. Mauro L. McCann D. Minchin B. Öztürk M. Robertson C. Sutton M.C. Villac 《Biological invasions》2003,5(4):365-377
During a European Union Concerted Action study on species introductions, an intercalibration workshop on ship ballast water
sampling techniques considered various phytoplankton and zooplankton sampling methods. For the first time, all the techniques
presently in use worldwide were compared using a plankton tower as a model ballast tank spiked with the brine shrimp and oyster
larvae while phytoplankton samples were taken simultaneously in the field (Helgoland Harbour, Germany). Three cone-shaped
and 11 non-cone shaped plankton nets of different sizes and designs were employed. Net lengths varied from 50 to 300 cm, diameters
9.7–50 cm, and mesh sizes 10–100 μm. Three pumps, a Ruttner sampler, and a bucket previously used in ballast water sampling
studies were also compared. This first assessment indicates that for sampling ballast water a wide range of techniques may
be needed. Each method showed different results in efficiency and it is unlikely that any of the methods will sample all taxa.
Although several methods proved to be valid elements of a hypothetical `tool box' of effective ship sampling techniques. The
Ruttner water sampler and the pump P30 provide suitable means for the quantitative phytoplankton sampling, whereas other pumps
prevailed during the qualitative trial. Pump P15 and cone-shaped nets were the best methods used for quantitative zooplankton
sampling. It is recommended that a further exercise involving a wider range of taxa be examined in a larger series of mesocosms
in conjunction with promising treatment measures for managing ballast water.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
740.
Yao S Sucheston LE Millen AE Johnson CS Trump DL Nesline MK Davis W Hong CC McCann SE Hwang H Kulkarni S Edge SB O'Connor TL Ambrosone CB 《PloS one》2011,6(2):e17251