James D. McGuffin-Cawley

Detection of Alpha-Methylacyl-CoA Racemase (AMACR), a Biomarker of Prostate Cancer, in Patient Blood Samples Using a Nanoparticle Electrochemical Biosensor.

Although still commonly used in clinical practice to screen and diagnose prostate cancer, there are numerous weaknesses of prostate-specific antigen (PSA) testing, including lack of specificity and the inability to distinguish between aggressive and indolent cancers. A promising prostate cancer biomarker, alpha-methylacyl-CoA racemase (AMACR), has been previously demonstrated to distinguish cancer from healthy and benign prostate cells with high sensitivity and specificity. However, no accurate clinically useful assay has been developed. This study reports the development of a single use, disposable biosensor for AMACR detection. Human blood samples were used to verify its validity, reproducibility and reliability. Plasma samples from 9 healthy males, 10 patients with high grade prostatic intraepithelial neoplasia (HGPIN), and 5 prostate cancer patients were measured for AMACR levels. The average AMACR levels in the prostate cancer patients was 10 fold higher (mean(SD) = 0.077 (0.10)) than either the controls (mean(SD) = 0.005 (0.001)) or HGPIN patients (mean(SD) = 0.004 (0.0005)). At a cutoff of between 0.08 and 0.9, we are able to achieve 100% accuracy in separating prostate cancer patients from controls. Our results provide strong evidence demonstrating that this biosensor can perform as a reliable assay for prostate cancer detection and diagnosis.

Predicting the occurance of unstable arc formations in laser hot-wire additive manufacturing

Additive manufacturing with metals is garnering interest for its potential in producing complex parts through near-net shape fabrication, with the potential to significantly reduce waste, cost, and lead-time. Use of the laser hot wire process for additive manufacturing offers relatively superior products when compared with other techniques. However, increasing the speed and material deposition rates, tends to induce unwanted arcs between the welding head and molten pool. These arcs produce spatter and irregularities in an otherwise relatively smooth, uninterrupted bead. Presented is a classifier that is able to predict the onset of these arcs on the scale of milliseconds before they occur, based only on voltage and current measurements. This classifier is developed to later be implemented as part of a LHW controller that can readily refute any arc generation.

Detection of alpha-methylacyl-CoA racemase (AMACR), a biomarker of prostate cancer, in patient blood samples using a nanoparticle electrochemical biosensor.

41 Background: A promising prostate cancer biomarker, alpha-methylacyl-CoA racemase (AMACR), has demonstrated the ability to distinguish cancer from healthy and benign cells with high sensitivity and specificity. However the lack of a good clinical assay has limited its translation into the clinic. Here we report on the development of a single use disposable biosensor for AMACR detection. METHODS This is a very inexpensive, small, single-use disposable sensor that requires only a drop of plasma and connects to a portable device. The biosensor utilizes the reaction of pristanic acid with a substrate that includes AMACR to produce Trans-2,3-dehydropritanayl-CoA plus H2O2. The biosensor utilizes iridium oxide nanoparticle catalyst to oxidize the H2O2 produced in the above metabolic pathway. Thus the oxidation of H2O2 yields a measurable current to quantify AMACR in the sample. This is the first in vitro assay method for AMACR based on this reaction mechanism. RESULTS In our study including plasma from 9 healthy males, 10 patients with high grade prostatic intraepithelial neoplasia and 5 prostate cancer patients we show 100% accuracy in separating prostate cancer patients from controls as well as those with benign prostate conditions. CONCLUSIONS Our data provides strong evidence for the ability of this biosensor to perform as a reliable assay for prostate cancer detection and diagnosis.

Calculation of energy balance and efficiency in Laser Hot-Wire (LHW) cladding process

Laser Hot-Wire (LHW) processing is a subset of freeform welding, which in turn is an extension of the well-established wire-based robotic cladding. The process is adaptable as a viable additive manufacturing (AM) technology. In LHW two separate heat sources are combined - a laser impinges on the surface of the workpiece and the feed wire is resistively heated through an external DC circuit. The two materials used in the experiments reported here are Ti-6Al-4V and Nickel 625. Advantages of the process are high deposition rate, high energy efficiency, and the ability to produced controlled unique microstructures. Preliminary calculations of energy efficiency and energy balance of the process are reported.

Work in progress - technology enhanced learning for engineering core courses

The potential benefits of employing technology enhanced learning by contemporaneously Web-posting searchable video recordings of engineering core courses is underway in the Case School of Engineering. Searchable video offers the possibility of using a lecture recording as reference material in a time-effective manner. Preliminary results indicate student attendance and participation in class are both positively impacted by the availability of recorded lectures. This suggests that student are employing the recordings as supplemental, rather than alternate primary material