7 results match your criteria: "The Univ. of Sydney[Affiliation]"

Abnormally shaped red blood cells (RBCs), called poikilocytes, can cause anemia. At present, the biochemical abnormalities in poikilocytes are not well understood. Normal RBCs and poikilocytes were analyzed using whole-blood and single-cell methods.

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β2-Agonists upregulate PDE4 mRNA but not protein or activity in human airway smooth muscle cells from asthmatic and nonasthmatic volunteers.

Am J Physiol Lung Cell Mol Physiol

February 2012

Cell Biology Group, Woolcock Institute of Medical Research, School of Medical Sciences, The Univ. of Sydney, Sydney, NSW, Australia.

β(2)-Adrenergic receptor (β2AR) agonists induce airway relaxation via cAMP. Phosphodiesterase (PDE)s degrade and regulate cAMP, and in airway smooth muscle (ASM) cells PDE4D degrades cAMP. Long-acting β(2)-agonists are now contraindicated as monotherapy for asthma, and increased PDE4D has been speculated to contribute to this phenomenon.

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Molecular mechanisms underlying the development of endothermy in birds (Gallus gallus): a new role of PGC-1 alpha?

Am J Physiol Regul Integr Comp Physiol

December 2007

Integrative Physiology, School of Biological Sciences A08, The Univ. of Sydney, NSW 2006, Australia.

In endotherms, plasticity of internal heat production in response to environmental variability is an important component of thermoregulation. During embryogenesis endotherms cannot regulate their body temperature metabolically and are therefore similar to ectotherms. The transition from ectothermy to endothermy occurs by the development of metabolic capacity during embryogenesis.

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Circulating ANG II modulates the baroreceptor reflex control of heart rate (HR), at least partly via activation of ANG II type 1 (AT1) receptors on neurons in the area postrema. In this study, we tested the hypothesis that the effects of circulating ANG II on the baroreflex also depend on AT1 receptors within the nucleus tractus solitarius (NTS). In confirmation of previous studies in other species, increases in arterial pressure induced by intravenous infusion of ANG II had little effect on HR in urethane-anesthetized rats, in contrast to the marked bradycardia evoked by equipressor infusion of phenylephrine.

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In the dark, light signals are conventionally routed through the following circuit: rods synapse onto rod bipolar (RB) cells, which in turn contact AII amacrine cells. AII cells segregate the light signal into the on and off pathways by making electrical synapses with on cone bipolar (CB) cells and glycinergic inhibitory chemical synapses with off CB cells. These bipolar cells synapse onto their respective ganglion cells, which transfer on and off signals to the visual centers of the brain.

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The dorsomedial hypothalamic nucleus (DMH) is believed to play a key role in mediating vasomotor and cardiac responses evoked by an acute stress. Inhibition of neurons in the rostral ventrolateral medulla (RVLM) greatly reduces the increase in renal sympathetic nerve activity (RSNA) evoked by activation of the DMH, indicating that RVLM neurons mediate, at least in part, the vasomotor component of the DMH-evoked response. In this study, the first aim was to determine whether neurons in the medullary raphe pallidus (RP) region also contribute to the DMH-evoked vasomotor response, because it has been shown that the DMH-evoked tachycardia is mediated by the RP region.

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The fate and transport of endosulfan (6,7,8,9,10,10-hexachloro-1,5, 5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin 3-oxide) applied to cotton (Gossypium hirsutum L.) fields were studied throughout three consecutive years on two selected locations in New South Wales (Australia). Rates of dissipation from foliage and soil, volatilization from the field, and transport of residues in irrigation and/or storm runoff waters were measured in order to estimate a total field balance.

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