Thoracic spinal cord intramedullary aspergillus invasion and abscess.

Invasive central nervous system aspergillosis is a rare form of fungal infection that presents most commonly in immunocompromised individuals. There have been multiple previous reports of aspergillus vertebral osteomyelitis and spinal epidural aspergillus abscess; however to our knowledge there are no reports of intramedullary aspergillus infection. We present a 19-year-old woman with active acute lymphoblastic leukemia who presented with several weeks of fevers and bilateral lower extremity weakness.

Dynamic contrast-enhanced optical imaging of in vivo organ function.

Conventional approaches to optical small animal molecular imaging suffer from poor resolution, limited sensitivity, and unreliable quantitation, often reducing their utility in practice. We previously demonstrated that the in vivo dynamics of an injected contrast agent could be exploited to provide high-contrast anatomical registration, owing to the temporal differences in each organ's response to the circulating fluorophore. This study extends this approach to explore whether dynamic contrast-enhanced optical imaging (DyCE) can allow noninvasive, in vivo assessment of organ function by quantifying the differing cellular uptake or wash-out dynamics of an agent in healthy and damaged organs.

In vivo optical imaging and dynamic contrast methods for biomedical research.

This paper provides an overview of optical imaging methods commonly applied to basic research applications. Optical imaging is well suited for non-clinical use, since it can exploit an enormous range of endogenous and exogenous forms of contrast that provide information about the structure and function of tissues ranging from single cells to entire organisms. An additional benefit of optical imaging that is often under-exploited is its ability to acquire data at high speeds; a feature that enables it to not only observe static distributions of contrast, but to probe and characterize dynamic events related to physiology, disease progression and acute interventions in real time.

In vivo 3D morphology of astrocyte-vasculature interactions in the somatosensory cortex: implications for neurovascular coupling.

Astrocytes are increasingly believed to play an important role in neurovascular coupling. Recent in vivo studies have shown that intracellular calcium levels in astrocytes correlate with reactivity in adjacent diving arterioles. However, the hemodynamic response to stimulation involves a complex orchestration of vessel dilations and constrictions that spread rapidly over wide distances.

High-speed vascular dynamics of the hemodynamic response.

While a range of cellular mechanisms have been proposed to underlie control of neurovascular coupling, a comprehensive, reconciliatory model has yet to be determined. To fit with such a model, it is essential that candidate mechanisms exhibit reaction times, spatial ranges, and speeds of propagation that are consistent with the vascular manifestations of the 'hemodynamic response'. Understanding these vascular dynamics is therefore a critical step towards developing a robust model of neurovascular coupling.