Beta-glucan attenuates cerebral ischemia/reperfusion-induced neuronal injury in a C57BL/J6 mouse model

Beta-glucans (ßg), that have many useful effects on human health, are natural polysaccharides. Our aim in this study was to determine useful effect of ßg against oxidative and neuronal damage caused by global cerebral ischemia/reperfusion (IR) in stroke imitated mice via surgical operation. A total of 40 mice divided into four equal groups randomly. The group 1 (sham operated) was kept as control. Bilateral carotid arteries of subjects in group 2 (I/R) and group 4 (I/ R + ßg) were clipped for 15 min, and the mice in group 4 (I/R + ßg) were treated with ßg (50 mg/kg/day), while the mice in group 2 (I/R) were treated with only vehicle for 10 days. The mice of group 3 (ßg) were treated with ßg for 10 days without carotid occlusion. Global cerebral I/R significantly increased oxidative stress and decreased members of anti-oxidant defense system. In addition, I/R caused histopathological damage in the brain tissue. However, ßg treatment ameliorated both oxidative and histopathological effects of I/R. Our present study showed that ßg treatment significantly ameliorated oxidative and histological damage in the brain tissue caused by cerebral I/R. Therefore, ßg treatment can be used as supportive care for ischemic stroke patients

In vivo Tracking of Mesenchymal Stem Cells Labeled with a Novel Chitosan-coated Superparamagnetic Iron Oxide Nanoparticles using 3.0T MRI

This study aimed to characterize and MRI track the mesenchymal stem cells labeled with chitosan-coated superparamagnetic iron oxide (Chitosan-SPIO). Chitosan-SPIO was synthesized from a mixture of FeCl2 and FeCl3. The human bone marrow derived mesenchymal stem cells (hBM-MSC) were labeled with 50 microg Fe/mL chitosan-SPIO and Resovist. The labeling efficiency was assessed by iron content, Prussian blue staining, electron microscopy and in vitro MR imaging. The labeled cells were also analyzed for cytotoxicity, phenotype and differentiation potential. Electron microscopic observations and Prussian blue staining revealed 100% of cells were labeled with iron particles. MR imaging was able to detect the labeled MSC successfully. Chitosan-SPIO did not show any cytotoxicity up to 200 microgram Fe/mL concentration. The labeled stem cells did not exhibit any significant alterations in the surface markers expression or adipo/osteo/chondrogenic differentiation potential when compared to unlabeled control cells. After contralateral injection into rabbit ischemic brain, the iron labeled stem cells were tracked by periodical in vivo MR images. The migration of cells was also confirmed by histological studies. The novel chitosan-SPIO enables to label and track MSC for in vivo MRI without cellular alteration.

Effects of nimodipine on multiunit activity of several brain structures following acute global cerebral ischemia-anoxia in cats

Se investigaron los efectos de nimodipina, una 1.4 dihidropiradina, bloqueador de los canales de calcio, sobre la actividad multineuronal (AMN) de varias estructuras cerebrales de gatos al aplicarse durante las 6 hrs siguientes a un estado de isquemia-anoxia cerebral global inducida por un paro cardiorespiratorio (PCR) de 10 min, así como en gatos expuestos a procedimientos control correspondientes al PCR. Se estudiaron cuatro grupos de gatos: 1 PCR y administración continua de nipodipina, 1 microg/kg/min iv durante 6 hrs; 2) PCR y administración continua del vehículo; 3) procedimietnos control y administración contínua de nipodipina 1 microg/kg/min iv durante 6 hrs; 4) procedimientos control y administración continua de vehículo. La AMN y el electroencefalograma desaparecieron durante el periodo de isquemia/anoxia; se recuperaron durante las horas siguientes al PCR, pero 6 hrs después del PCR la AMN era aún menor que sus valores previos al paro en todas las estructuras subcorticales que se registraron. Durante la recuperación de la actividad EEG se presentaron ondas delta, espigas aislada y trenes de ondas EEG rápidas (20 a 22 HZ). La nimodipina inhibió los aumentos de la AMN que de otro modo se hubieran presentado en la formación reticular mesencefálica, hipocampo y putamen, pero no en el hipotálamo ventromedial, en las horas siguientes al periodo de isquemia/anoxia cerebral global aguda. En los gatos sometidos a PCR y tratados con nimodipina no se observaron espigas aislada ni trenes de actividad EEG rápida. En los gatos control, no sometidos a PCR, la nimodipina redujo significativamente la AMN en el hipocampo pero no en otras estructuras cerebrales. Los resultados sugieren la participación de canales de calcio sensibles a 1,4-dihidropiridina en los mecanismos celulares relacionados con la actividad neuronal que se presenta después de la isquemia-anoxia, así como la posible relación entre los efectos de nimodipina sobre la AMN y las majores condiciones funcionales del sistema nervioso central después de un periodo de isquemia-anoxia cerebral global aguda.

Measurements of Cerebral Blood Flow in Delayed Carbon Monoxide Sequelae Using Xenon lnhalation CT Scan

The regional cerebral blood flow of four patients with delayed carbon monoxide sequelae and four age matched controls was measured, using a xenon inhalation CT scan (GE 9800). Variable patterns of decreased cerebral blood perfusion according to the clinical state of the patient were noted among the patients. Follow up studies, 2 months later, indicated that there was a correlation between the fluctuation of symptoms and the changes in regional cerebral blood flow. It is suggested that the impairment of cerebral perfusion may play a critical role in delayed carbon monoxide sequelae.

Consumo de glucosa bajo acción de una cocarboxilasa no degradable, utilizando cianuro como estimulante / Consuption of glucose under the action of a non degradable cocaiboxilase using cyamide as stimulant

Se determinó la variación del consumo de glucosa, por acción de una cocarboxilasa no degradable en animal sano y en animal intoxicado con cianuro como estimulante, midiendo las alteraciones electrofisiológicas de los quimiorreceptores aórticos y carotídeos. La conclusión fue que la cocarboxilasa no degradable inteviene en el metabolismo de la glucosa favorecendo funcional y notoriamente al músculo cardiaco sometido a la anoxia del cianuro, el cual reproduce masivametne los efectos de la isquemia