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The hippocampus contains distinct populations of neurons organized into separate anatomical subfields and layers with differential vulnerability to pathological mechanisms. The ability of in vivo neuroimaging to pinpoint regional vulnerability is especially important for better understanding of hippocampal pathology at the early stage of neurodegenerative disorders and for monitoring future therapeutic strategies. This is the case for instance in multiple sclerosis whose neurodegenerative component can affect the hippocampus from the early stage. We challenged the capacity of two models, i.e. the classical diffusion tensor imaging (DTI) model and the neurite orientation dispersion and density imaging (NODDI) model, to compute quantitative diffusion MRI that could capture microstructural alterations in the individual hippocampal layers of experimental-autoimmune encephalomyelitis (EAE) mice, the animal model of multiple sclerosis. To achieve this, the hippocampal anatomy of a healthy mouse brain was first explored ex vivo with high resolution DTI and NODDI. Then, 18 EAE mice and 18 control mice were explored 20 days after immunization with in vivo diffusion MRI prior to sacrifice for the histological quantification of neurites and glial markers in each hippocampal layer. Fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD) maps were computed from the DTI model while the orientation dispersion index (ODI), the neurite density index (NDI) and the volume fraction of isotropic diffusivity (isoVF) maps were computed from the NODDI model. We first showed in control mice that color-coded FA and ODI maps can delineate three main hippocampal layers. The quantification of FA, AD, RD, MD, ODI, NDI and isoVF presented differences within these 3 layers, especially within the molecular layer of the dentate gyrus which displayed a specific signature based on a combination of AD (or MD), ODI and NDI. Then, the comparison between EAE and control mice showed a decrease of AD (p = 0.036) and of MD (p = 0.033) selectively within the molecular layer of EAE mice while NODDI indices did not present any difference between EAE and control mice in any layer. Histological analyses confirmed the differential vulnerability of the molecular layer of EAE mice that exhibited decreased dendritic length and decreased dendritic complexity together with activated microglia. Dendritic length and intersections within the molecular layer were independent contributors to the observed decrease of AD (R 2  = 0.37 and R 2  = 0.40, p < 0.0001) and MD (R 2  = 0.41 and R 2  = 0.42, p < 0.0001). We therefore identified that NODDI maps can help to highlight the internal microanatomy of the hippocampus but NODDI still presents limitations in grey matter as it failed to capture selective dendritic alterations occurring at early stages of a neurodegenerative disease such as multiple sclerosis, whereas DTI maps were significantly altered., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The dental school arose from the premise that a dental school would round out the university and add prestige to the burgeoning Health Professions Division with its five schools and eight health programs. The school was founded in light of the following circumstances. Patient Pool Evaluation of community facilities and services revealed that there was an increasing patient pool, without disturbing the present mix. There was evidence of a need for dental care for large numbers of unserved or underserved people. Financial Considerations Proforma and cash flow budget projections showed financial stability of this project. The university was recognized to have the ability to absorb initial capital costs. HPD had a history of the success in functioning with tuition-dependent budgets. University Factors The university has had success in establishing and operating five health professions schools. A complete and experienced infrastructure has existed for sixteen years in the University and in the Health Professions Division. The university would provide unconditional administrative support.

This study examined the effect of storage, for periods varying up to 24 weeks and at temperatures from -12 degrees C. to 50 degrees C., on the compression, tension, torsion, and bend properties of size 100 hand-rolled gutta-percha cones. All of the properties changed during storage, with the largest changes occurring at the highest temperatures, the smallest changes occurring at the lowest temperatures, and the greatest rate of change occurring during the initial 40- to 60-day storage period. All of the cones tested were subjectively found to be clinically usable. Since ideal characteristics or standards for mechanical properties are nonexistent, assessment of the changes is speculative and arbitrary. The condition of cones at which clinicians decide they are unusuable also varies widely. Continual study of this problem is indicated and important.

Enterococci that persisted in debrided, medicated root canals were tested by the Kirby-Bauer procedure for sensitivity to various antibiotics. The 50 strains tested were uniformly sensitive to ampicillin and vancomycin. More than 90% were also sensitive to erythromycin. Varying degrees of sensitivity and resistance were noted to bacitracin, cephaloridine, cephalothin, chloramphenicol, gentamicin, and tetracycline. All organisms were either partly or wholly resistant to clindamycin; penicillin; streptomycin; and sulfadiazine, sulfamerazine, and sulfamethazine (triple sulfas).