Mouse intermittent hypoxia mimicking apnoea of prematurity: effects on myelinogenesis and axonal maturation.

Premature babies are at high risk for both infantile apnoea and long-term neurobehavioural deficits. Recent studies suggest that diffuse structural changes in brain white matter are a positive predictor of poor cognitive outcomes. Since oligodendrocyte maturation, myelination, axon development, and synapse formation mainly occur in the third trimester of gestation and first postnatal year, infantile apnoea could lead to and/or exaggerate white matter impairments in preterm neonates.

A neonatal mouse model of intermittent hypoxia associated with features of apnea in premature infants.

A neonatal mouse model of intermittent hypoxia (IH) simulating the recurring hypoxia/reoxygenation episodes of apnea of prematurity (AOP) was developed. C57BL/6 P2 pups were culled for exposure to either intermittent hypoxia or intermittent air as control. The IH paradigms consisted of alternation cycles of 20.

Alkylation of a dimolybdenum SO bridge, subsequent reactions, and characterization of the thioperoxide bridge.

The SO bridge of the complex, [Mo(2)(NTo)(2)(S(2)P(OEt)(2))(2)(mu-O(2)CMe)(mu-SBn)(mu-SO)], 1, displayed nucleophilicity at O, giving alkylation products [Mo(2)(NTo)(2)(S(2)P(OEt)(2))(2)(mu-O(2)CMe)(mu-SBn)(mu-SOR)](+), 4(+), which contained the thioperoxide bridge. These cations were then subject to nucleophilic attack by two pathways. Debenzylation of the bridge thiolate in 4(+) afforded neutral [Mo(2)(NTo)(2)(S(2)P(OEt)(2))(2)(mu-O(2)CMe)(mu-S)(mu-SOR)], 5; de-esterification of a dithiophosphate ligand in 4(+) gave [Mo(2)(NTo)(2)(S(2)P(O)(OEt))(S(2)P(OEt)(2))(mu-O(2)CMe)(mu-SBn)(mu-SO)], 6, which contained a monoester, dithiophosphate ligand.

Semi-automated region of interest generation for the analysis of optically recorded neuronal activity.

Bath-applied membrane-permeant Ca(2+) indicators offer access to network function with single-cell resolution. A barrier to wider and more efficient use of this technique is the difficulty of extracting fluorescence signals from the active constituents of the network under study. Here we present a method for semi-automatic region of interest (ROI) detection that exploits the spatially compact, slowly time-varying character of the somatic signals that these indicators typically produce.

Functional imaging reveals respiratory network activity during hypoxic and opioid challenge in the neonate rat tilted sagittal slab preparation.

In mammals, respiration-modulated networks are distributed rostrocaudally in the ventrolateral quadrant of the medulla. Recent studies have established that in neonate rodents, two spatially separate networks along this column-the parafacial respiratory group (pFRG) and the pre-Bötzinger complex (preBötC)-are hypothesized to be sufficient for respiratory rhythm generation, but little is known about the connectivity within or between these networks. To be able to observe how these networks interact, we have developed a neonate rat medullary tilted sagittal slab, which exposes one column of respiration-modulated neurons on its surface, permitting functional imaging with cellular resolution.