Plos One
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Inhibitory interneurons in the cerebellar granular layer are more heterogeneous than traditionally depicted. In contrast to Golgi cells, which are ubiquitously distributed in the granular layer, small fusiform Lugaro cells and globular cells are located underneath the Purkinje cell layer and small in number. Globular cells have not been characterized physiologically. ⋯ The two monoamines also facilitated small Golgi cell firing, but only 5-HT elicited firing in small fusiform Lugaro cells. Furthermore, globular cells likely received excitatory monosynaptic inputs through mossy fibers. Because globular cells project their axons long in the transversal direction, the neuronal circuit that includes interplay between Purkinje cells and globular cells could regulate Purkinje cell activity in different microzones under the influence of monoamines and mossy fiber inputs, suggesting that globular cells likely play a unique modulatory role in cerebellar motor control.
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Severe acute respiratory syndrome (SARS) emerged in China in 2002 and spread to other countries before brought under control. Because of a concern for reemergence or a deliberate release of the SARS coronavirus, vaccine development was initiated. Evaluations of an inactivated whole virus vaccine in ferrets and nonhuman primates and a virus-like-particle vaccine in mice induced protection against infection but challenged animals exhibited an immunopathologic-type lung disease. ⋯ These SARS-CoV vaccines all induced antibody and protection against infection with SARS-CoV. However, challenge of mice given any of the vaccines led to occurrence of Th2-type immunopathology suggesting hypersensitivity to SARS-CoV components was induced. Caution in proceeding to application of a SARS-CoV vaccine in humans is indicated.
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Gentamicin nephrotoxicity is one of the most common causes of acute kidney injury (AKI). Hypoxia-inducible factor (HIF) is effective in protecting the kidney from ischemic and toxic injury. Increased expression of HIF-1α mRNA has been reported in rats with gentamicin-induced renal injury. ⋯ HIF activation improved the creatinine clearance and proteinuria in gentamicin-induced AKI. HIF activation also ameliorated the extent of histologic injury and reduced macrophage infiltration into the tubulointerstitium. In gentamicin-induced AKI, the activation of HIF by cobalt or DMOG attenuated renal dysfunction, proteinuria, and structural damage through a reduction of oxidative stress, inflammation, and apoptosis in renal tubular epithelial cells.
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The olivary pretectal nucleus (OPN) is a small midbrain structure responsible for pupil constriction in response to eye illumination. Previous electrophysiological studies have shown that OPN neurons code light intensity levels and therefore are called luminance detectors. Recently, we described an additional population of OPN neurons, characterized by a slow rhythmic pattern of action potentials in light-on conditions. Rhythmic patterns generated by these cells last for a period of approximately 2 minutes. ⋯ We found that oscillatory neurons were able to fire rhythmically in darkness and were responsive to eye illumination in a manner resembling that of luminance detectors. Their firing rate increased together with the strength of the light stimulation. In addition, during the train of light pulses, we observed two profiles of responses: oscillation-preserving and oscillation-disrupting, which occurred during low- and high-illuminance stimuli presentation respectively. Moreover, we have shown that contralateral retina inactivation eliminated oscillation and significantly reduced the firing rate of oscillatory cells. These results suggest that contralateral retinal innervation is crucial for the generation of an oscillatory pattern in addition to its role in driving responses to visual stimuli.
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In vitro studies have well established the neuroprotective action of the noble gas argon. However, only limited data from in vivo models are available, and particularly whether postexcitotoxic or postischemic argon can provide neuroprotection in vivo still remains to be demonstrated. Here, we investigated the possible neuroprotective effect of postexcitotoxic-postischemic argon both ex vivo in acute brain slices subjected to ischemia in the form of oxygen and glucose deprivation (OGD), and in vivo in rats subjected to an intrastriatal injection of N-methyl-D-aspartate (NMDA) or to the occlusion of middle-cerebral artery (MCAO). ⋯ These results extend previous data on the neuroprotective action of argon. Particularly, taken together with previous in vivo data that have shown that intraischemic argon has neuroprotective action at both the cortical and subcortical level, our findings on postischemic argon suggest that this noble gas could be administered during but not after ischemia, i.e. before but not after reperfusion has occurred, in order to provide cortical neuroprotection and to avoid increasing subcortical brain damage. Also, the effects of argon are discussed as regards to the oxygen-like chemical, pharmacological, and physical properties of argon.