Project description:In ischemic stroke, DWI-T2 mismatch (positive signals on DWI but negative signals on T2) indicates ischemia within 4.5 h. However, the molecular expression pattern of this region remains elusive. This project aimed to reveal the proteomics profiling of the brain tissues at DWI-T2 mismatch, T2(+), and contralateral regions of brain within 4.5 h after middle cerebral artery occlusion compared with naïve brains of mice.
Project description:Transient hypoxia in pregnancy stimulates a physiological reflex response that redistributes blood flow and defends oxygen delivery to the fetal brain. The chemoreceptor reflex that is responsible for this physiological response is dependent on glutamatergic neurotransmission which, in times of vigorous activity, could produce cell death secondary to calcium uptake. We designed the present experiment to test the hypotheses that transient hypoxia produces damage of the cerebral cortex and that ketamine, an antagonist of NMDA receptors, reduces the damage. Late-gestation, chronically catheterized fetal sheep were subjected to a 30 min period of ventilatory hypoxia that decreased fetal PaO2 from 17±1 to 10±1 mm Hg, or normoxia (PaO2 17±1 mm Hg), with or without pretreatment (10 min before hypoxia/normoxia) with ketamine (3 mg/kg, iv). One day (24 h) after hypoxia/normoxia, fetal cerebral cortex was removed and mRNA extracted for transcriptomics and systems biology analysis. Hypoxia stimulated a transcriptomics response consistent with a reduction in cellular metabolism and an increase in inflammation. Ketamine pretreatment reduced both of these responses. The inflammation response modeled with transcriptomic system biology was validated by immunohistochemistry and showed increased abundance of microglia/macrophages after hypoxia in the cerebral cortical tissue that ketamine significantly reduced. We conclude that transient hypoxia produces inflammation of the fetal cerebral cortex and that ketamine, in a standard clinical dose, reduces the inflammation response. 4 groups: hypoxia, hypoxia plus ketamine, normoxia, normoxia plus ketamine. Hypoxia produced by low PO2 in maternal inspired gas for 30 min, followed by normoxia recovery for 23.5 hours. Control fetuses maintained at normoxia for 30 min, followed by another 23.5 h of normoxia. Fetal frontal cerebral cortex collected for mRNA at end of 23.5 h recovery period.
Project description:cea06-01_uranyl_nitrate - time course uranyl nitrate response - Dynamic analyses of transcriptomic response to urany l nitrate - Plants are grown on sand and transfert in hydroponic culture during 2 days and then expose or not to 50uM uranyl nitrate at pH 4.5 in water or only to water at pH 4.5. Roots and leaves were collected independently after 2h, 6h and 30h of treament. Keywords: organ comparison,time course,treated vs untreated comparison 20 dye-swap - CATMA arrays
Project description:Gene expression analysis of motor cortex after spinal C3 lesion Dorsal column wire knife lesions: Adult female Fischer 344 rats weighing 150-200 gm were used. Animals underwent a laminectomy at spinal level C3. Dorsal funiculus lesions were made in the middle of C3 using a Kopf microwire device (Kopf Instruments, Tujunga, CA). After fixation in a spinal stereotaxic unit, a small dural incision was made. The wire knife was lowered into the spinal cord to a depth of 1.1 mm ventral to the dorsal cord surface and 1.1 mm to the left of the midline. The tip of the wireknife was extruded, forming a 2.25 mm-wide arc that was raised to the dorsal surface of the cord. To ensure complete axotomy of the dorsal funiculus, spinal tissue was compressed against the microwire knife surface using a microaspiration pipette until all visible white matter was transected. Cortical microdissection: The forelimb and hindlimb motor cortex were microdisected from rat cortices: Rostral to Bregma: an area from 2.0 to 4.5 mm mediolateral and from 0 to 2 mm anterior-posterior Caudal to Bregma: an area from 2.0 to 3.5 mediolateral and from 0 to 3 mm caudal to Bregma. Only the inferior half of the cortex containing layer V corticospinal motor neurons was sampled in each region.