Publications by authors named "Donald Spencer"

Institutions must decide how to manage the use of clinical data to support research while ensuring appropriate protections are in place. Questions about data use and sharing often go beyond what the Health Insurance Portability and Accountability Act of 1996 (HIPAA) considers. In this article, we describe our institution's governance model and approach.

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In the highly dynamic metabolic landscape of a neuron, mitochondrial membrane architectures can provide critical insight into the unique energy balance of the cell. Current theoretical calculations of functional outputs like adenosine triphosphate and heat often represent mitochondria as idealized geometries, and therefore, can miscalculate the metabolic fluxes. To analyze mitochondrial morphology in neurons of mouse cerebellum neuropil, 3D tracings of complete synaptic and axonal mitochondria were constructed using a database of serial transmission electron microscopy (TEM) tomography images and converted to watertight meshes with minimal distortion of the original microscopy volumes with a granularity of 1.

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Reliable timing of cortical spikes in response to visual events is crucial in representing visual inputs to the brain. Spikes in the primary visual cortex (V1) need to occur at the same time within a repeated visual stimulus. Two classical mechanisms are employed by the cortex to enhance reliable timing.

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Thalamic inputs strongly drive neurons in the primary visual cortex, even though these neurons constitute only approximately 5% of the synapses on layer 4 spiny stellate simple cells. We modeled the feedforward excitatory and inhibitory inputs to these cells based on in vivo recordings in cats, and we found that the reliability of spike transmission increased steeply between 20 and 40 synchronous thalamic inputs in a time window of 5 milliseconds, when the reliability per spike was most energetically efficient. The optimal range of synchronous inputs was influenced by the balance of background excitation and inhibition in the cortex, which could gate the flow of information into the cortex.

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The Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study evaluated feasible treatment strategies to improve clinical outcomes for real-world patients with treatment-resistant depression. Although the study found no clear-cut "winner", it does provide guidance on how to start therapy and how to proceed if initial treatment fails.

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Purpose: We undertook a study to confirm and extend preliminary findings that participants with major depressive disorder (MDD) in primary care and specialty care settings have with equivalent degrees of depression severity and an indistinguishable constellation of symptoms.

Methods: Baseline data were collected for a distinct validation cohort of 2,541 participants (42% primary care) from 14 US regional centers comprised of 41 clinic sites (18 primary care, 23 specialty care). Participants met broadly inclusive eligibility criteria requiring a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnosis of MDD and a minimum depressive symptom score on the 17-item Hamilton Rating Scale for Depression.

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A transgenic line of subterranean clover (Trifolium subterraneum) containing a gene for a sulphur-rich sunflower seed albumin (ssa gene) and a gene conferring tolerance to the herbicide phosphinothricin (bar gene) was previously shown to stably express these genes as far as the T3 generation. In subsequent generations there was a progressive decline in the level of expression of both of these genes such that, by the T7 generation, the plants were almost completely susceptible to the herbicide and the mean level of sunflower seed albumin was reduced to 10-30% of the level in the T2 and T3 generations. The decline in SSA protein correlated closely with a decline in the level of ssa RNA.

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In 1980, Wildman et al. (Bot Gaz 141: 24-36) proposed a three-dimensional model for chloroplast structure whereby the grana were arranged in non-overlapping rows, like beads on a string. This string-of-grana model was developed from phase microscope analysis of living cells and partially disrupted, isolated chloroplasts.

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Purpose: No study has directly compared the clinical features of depression for patients entering clinical trials using identical enrollment criteria at primary care (PC) and specialty care (SC) settings. The Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study (http://www.star-d.

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