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Scott Graham

Publications and source records attributed to Scott Graham.

4 recordsLinked to original sources

Memory training alters hippocampal neurochemistry in healthy elderly.

Accumulating epidemiological evidence supports the notion of brain reserve, but there has been no investigation of neurobiological change associated with brief mental activation training in humans. Healthy older individuals were therefore investigated with magnetic resonance spectroscopy (MRS) in different brain regions before and after 5 weeks of focused memory training. Recall of a test-word list of > 23 items was achieved accompanied by elevation of creatine and choline signals in the hippocampus. Those at risk for neural dysfunction, as indicated by lower neurometabolites at baseline, demonstrated the largest MRS increases after training. Biochemical changes related to cellular energy and cell-membrane turnover were found to increase after structured memory exercises and were limited to the medial temporal lobe.

Aged↗

Patched 1 conditional null allele in mice.

The patched gene (Ptc) is a member of the hedgehog signaling pathway which plays a central role in the development of many invertebrate and vertebrate tissues. In addition, Ptc and a number of other pathway members are mutated in some common human cancers. Patched is the receptor for the hedgehog ligand and in the mouse ablation of the Ptc gene leads to developmental defects and an embryonic lethal phenotype. Here we describe a conditional Ptc allele in mice which will have utility for the temporospatial ablation of Ptc function.

Alleles↗

Non-linear fitting of mechanical data for efficacy determination of single versus double bundle Achilles tendon grafts for PCL reconstructions.

The Posterior Cruciate Ligament (PCL) consists of two primary bundles and is the primary restraint to posterior tibial translation. The emergence of the Posterior Tibial Inlay Technique (PTIT) has demonstrated a mechanical advantage over the commonly used Tibial Tunnel Method (TTM). This study was designed to investigate the effects on knee mechanics from both a Single-bundle (SB) and Double-bundle (DB) Achilles tendon PCL reconstruction using a PTIT. The investigators hypothesized that a DB graft demonstrates a mechanical advantage compared to the SB graft. A materials testing machine provided six sequential loading cycles of 100 N while total translation was measured. The testing was conducted at 90 degrees, 60 degrees, 30 degrees and 10 degrees of flexion in neutral tibial rotation. While the mechanical advantages of the DB graft were detected, specifically at small laxity values and in the physiological range of normal gait, the additional complexity of the technique may clinically outweigh the mechanical advantages.

Achilles Tendon↗