Global cerebral perfusion parameters were measured using dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) in eight healthy volunteers examined during normal breathing and spontaneous hyperventilati...Global cerebral perfusion parameters were measured using dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) in eight healthy volunteers examined during normal breathing and spontaneous hyperventilation. DSC-MRI-based cerebral blood flow (CBF) de-creased during hyperventilation in all volun-teers (average decrease 29%), and the corre-sponding global CBF estimates were 73±19ml/ (min100g) during normal breathing and 52± 7.9ml/(min100g) during hyperventilation (mean ±SD, n=8). Furthermore, the hypocapnic condi-tions induced by hyperventilation resulted in a prolongation of the global mean transit time (MTT) by on average 14%. The observed CBF estimates appeared to be systematically over-estimated, in accordance with previously pub-lished DSC-MRI results, but reduced to more reasonable levels when a previously retrieved calibration factor was applied.展开更多
Delivering pharmacologic agents directly into the brain has been proposed as a means of bypassing the blood brain barrier.However,despite 16 years of research on a number of central nervous system disorders,an effecti...Delivering pharmacologic agents directly into the brain has been proposed as a means of bypassing the blood brain barrier.However,despite 16 years of research on a number of central nervous system disorders,an effective treatment using this strategy has only been observed in the brain tumor glioblastoma multiforme.Within this study we propose a novel system for delivering drugs into the brain named the simple diffusion (SDD) system.To validate this technique,rats were subjected to a single intracranial (at the caudate nucleus),or intraperitoneal injection,of the compound citicoline,followed two hours later by a permanent middle cerebral artery occlusion (pMCAO).Results showed that 12 h after pMCAO,with 0.0025 g kg-1 citicoline,an infarct volume 1/6 the size of the intraperitoneal group was achieved with a dose 1/800 of that required for the intraperitoneal group.These results suggest that given the appropriate injection point,through SDD a pharmacologically effective concentration of citicoline can be administered.展开更多
文摘Global cerebral perfusion parameters were measured using dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) in eight healthy volunteers examined during normal breathing and spontaneous hyperventilation. DSC-MRI-based cerebral blood flow (CBF) de-creased during hyperventilation in all volun-teers (average decrease 29%), and the corre-sponding global CBF estimates were 73±19ml/ (min100g) during normal breathing and 52± 7.9ml/(min100g) during hyperventilation (mean ±SD, n=8). Furthermore, the hypocapnic condi-tions induced by hyperventilation resulted in a prolongation of the global mean transit time (MTT) by on average 14%. The observed CBF estimates appeared to be systematically over-estimated, in accordance with previously pub-lished DSC-MRI results, but reduced to more reasonable levels when a previously retrieved calibration factor was applied.
基金supported by the National Natural Science Foundation of China(Grant Nos. 30972811 and 81071148)Natural Science Foundation of Beijing(Grant No. 7093137)
文摘Delivering pharmacologic agents directly into the brain has been proposed as a means of bypassing the blood brain barrier.However,despite 16 years of research on a number of central nervous system disorders,an effective treatment using this strategy has only been observed in the brain tumor glioblastoma multiforme.Within this study we propose a novel system for delivering drugs into the brain named the simple diffusion (SDD) system.To validate this technique,rats were subjected to a single intracranial (at the caudate nucleus),or intraperitoneal injection,of the compound citicoline,followed two hours later by a permanent middle cerebral artery occlusion (pMCAO).Results showed that 12 h after pMCAO,with 0.0025 g kg-1 citicoline,an infarct volume 1/6 the size of the intraperitoneal group was achieved with a dose 1/800 of that required for the intraperitoneal group.These results suggest that given the appropriate injection point,through SDD a pharmacologically effective concentration of citicoline can be administered.
