Background and Purpose To demonstrate that gradual and continuous WM change and the associated cognitive decline in type 2 diabetes mellitus (T2DM) patients can be captured by DTI parameters and the DTI parameters can be used to complement neuropsychological test scores in identifying T2DM patients with and without mild cognitive impairment (MCI). Materials and Methods Forty-two T2DM patients, divided into a group with MCI (DM-MCI; n = 20) and a group with normal cognition (DM-NC; n = 22) based on cognitive assessments, were enrolled together with age-, gender-, and education-matched healthy controls (HC; n = 26). DTI was performed at 3 Tesla, followed by an analysis using tract-based spatial statistics (TBSS) to investigate the differences in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λ1), and radial diffusivity (λ23) among the groups. A receiver operating characteristic (ROC) analysis was used to assess the performance of using DTI parameters for separating the two T2DM groups. Results The whole-brain TBSS analysis revealed that 7.3% and 24.9% of the WM exhibited decreased FA and increased MD (p < 0.05), respectively, between the DM-MCI and the DM-NC groups, while considerably larger WM regions showed FA (36.6%) and MD (58.8%) changes between the DM-MCI and the HC groups. These changes were caused primarily by an elevated radial diffusivity observed in the DM-MCI patients. Radial diffusivity also exhibited subtle but statistically significant changes between the DM-NC and the HC group. Analyses on individual fiber tracts showed pronounced FA reduction and MD elevation in regions related to cognitive functions. The ROC analysis on the right cingulum (hippocampus) showed that FA produced a larger area under the curve (AUC = 0.832) than MD (0.753) for separating MCI from normal cognition among T2DM patients. When FA was combined with MD, the AUC was further improved to 0.857. Conclusion This study demonstrates that the DTI parameters can show a significant difference between the T2DM patients with and without MCI, suggesting their potential use as an imaging marker for detecting cognitive decline in T2DM patients. More importantly, this study also suggests that the DTI parameters may capture gradual and continuous WM changes that can be associated with early stages of cognitive decline in T2DM patients before they can be diagnosed clinically using the conventional neuropsychological tests.

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We have previously shown that differentiation of embryonal carcinoma (EC) cells leads to both increased binding of FGF (fibroblast growth factor) and suppression of k-FGF expression. In the current study, we examined the expression of FGF receptors by EC cells, EC-derived differentiated cells and early mammalian embryos using the technique of reverse transcription-polymerase chain reaction (RT-PCR). We determined that both mouse, F9, and human, NT2/D1, EC cells as well as their differentiated counterparts express transcripts for two forms of FGF receptors, bek (bacterially expressed kinase) and flg (fms-like gene). In addition, we determined that mouse blastocysts express flg transcripts. The presence of FGF receptor transcripts in early embryos and the previous finding of FGF-related activity in medium conditioned by mouse blastocysts argue that the FGF family plays important roles during early mammalian development.

The U.S. Geological Survey, in cooperation with the U.S. Air Force Civil Engineering Center, investigated the use of surface geophysical methods to delineate the top of the Cretaceous Pierre Shale along survey transects in selected areas within and near Ellsworth Air Force Base, South Dakota. Two complementary geophysical methods-electrical resistivity and passive seismic-were used along 26 co-located transect surveys within and near Ellsworth Air Force Base for a total of 12.7 line-kilometers. Electrical resistivity results were analyzed using EarthImager2D electrical resistivity tomography processing and inversion software. Two-dimensional earth models showing the electrical properties of the subsurface were evaluated by directly comparing the high and low subsurface resistivity values to a surficial geologic map and nearby wells with driller logs. Passive seismic data were analyzed using the horizontal-to-vertical spectral ratio method to determine the depth to the Pierre Shale at each survey point. The electrical resistivity and passive seismic results were compared to driller logs from nearby wells to delineate the top of the Pierre Shale. The depth to the Pierre Shale along the transects ranged from about 2.4 to 20.3 meters, and mean and median depths were about 9.2 and 9.0 meters, respectively. The elevation of the Pierre Shale and thickness of unconsolidated deposits generally increased with land-surface elevation from south to north; however, some transects displayed topographically high and low areas that sometimes did not correlate with land-surface topography and may affect local groundwater flow.

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