Cause and Amelioration of MRI-Induced Heating Through Medical Implant Lead Wires

The RF fields present in magnetic resonance imaging (MRI) scanners can induce hazardous heating in patients wearing medical implants. The inherent design and locale of deep brain stimulators (DBS) and spinal cord stimulators (SCS) make them particularly susceptible. We apply antenna concepts and use electromagnetic (EM) simulation to explain the phenomenon and anticipate its sensitivity to lead wire length. We anticipate that a DC resistance of less than 50 Ω/m and an RF impedance of more than 1:23kΩ/m would be required for a safe electrode for SCS use. We investigate the possibility of manipulating wire conductivity and diameter in order to use the skin depth effect to achieve a safe electrode. The effect of the thickness and permittivity of insulation surrounding the wires is explored

Measurement of antennas and microwave components using time-domain reflectometry of a voltage impulse

Band-pass microwave systems such as ultra-wideband antennas are traditionally characterized in the frequency-domain through a vector network analyzer in an anechoic chamber. A recent study proved antennas could be accurately measured in the time-domain using a step-function time-domain reflectometer (TDR), without the need for an anechoic chamber. We propose a new advance in the TDR characterization method. An impulse generator is employed in place of the step generator in a TDR set-up. The advantage conferred by this change is that more energy is available beyond a given frequency than with a step, and so a higher signal-to-noise ratio is achieved. The theoretical result is compared with measurement

Impulse TDR and its application to measurement of antennas

The traditional stimulus signal used in a time-domain reflectometer (TDR) is a voltage step. We propose an alternative technique, whereby an impulse generator is employed in place of the step generator in a TDR. The advantage conferred by “impulse TDR” is that more energy is available at higher frequencies than with conventional step TDR, and so a higher bandwidth and signal-to-noise ratio (SNR) is achieved. The theoretical result is compared with measurement

Drosophila Larval NMJ Immunohistochemistry

The Drosophila neuromuscular junction (NMJ) is an established model system used for the study of synaptic development and plasticity. The widespread use of the Drosophila motor system is due to its high accessibility. It can be analyzed with single-cell resolution. There are 30 muscles per hemisegment whose arrangement within the peripheral body wall are known. A total of 31 motor neurons attach to these muscles in a pattern that has high fidelity. Using molecular biology and genetics, one can create transgenic animals or mutants. Then, one can study the developmental consequences on the morphology and function of the NMJ. Immunohistochemistry can be used to clearly image the components of the NMJ. In this article, we demonstrate how to use antibody staining to visualize the Drosophila larval NMJ

Evaluating the effects of a multi-component support service for people recently diagnosed with dementia and their carers: A qualitative study

Abstract Introduction Although prior research has provided an understanding of the needs of people living with dementia (PLWD) and their carers, less is known about how tailored multicomponent interventions impact their lives. This study explored the effect of providing ongoing support to people who had been recently diagnosed with dementia and to their carers. Methods We conducted interviews with a convenience sample of key stakeholders: 11 interviews with people who had dementia and their familial carers (n = 14) and six interviews with staff and other practitioners involved with the service (n = 13). Inductive thematic analysis was performed on the data. Results Four themes were developed: the service as a source of respite, peer support, activities as facilitators of emotional wellbeing, and social support. The service was well‐respected, credible, and trusted and was highly valued by practitioners, clients, and carers. It had a clear role in supporting PLWD and their carers. Peer support provided through the service contributed to greatly reducing self‐reported carer burden. Conclusion Recommendations arising from this study include offering holistic services to PLWD and their carers, developing activities for men, raising awareness of services among practitioners working with PLWD, and improving partnerships between services and agencies working with older people. Patient or Public Contribution Service users were consulted on the themes generated from the data and were asked to provide feedback to help guide the interpretation of the data and ensure this reflected their views and experiences

Cranberry and Grape Seed Extracts Inhibit the Proliferative Phenotype of Oral Squamous Cell Carcinomas

Proanthocyanidins, compounds highly concentrated in dietary fruits, such as cranberries and grapes, demonstrate significant cancer prevention potential against many types of cancer. The objective of this study was to evaluate cranberry and grape seed extracts to quantitate and compare their anti-proliferative effects on the most common type of oral cancer, oral squamous cell carcinoma. Using two well-characterized oral squamous cell carcinoma cell lines, CAL27 and SCC25, assays were performed to evaluate the effects of cranberry and grape seed extract on phenotypic behaviors of these oral cancers. The proliferation of both oral cancer cell lines was significantly inhibited by the administration of cranberry and grape seed extracts, in a dose-dependent manner. In addition, key regulators of apoptosis, caspase-2 and caspase-8, were concomitantly up-regulated by these treatments. However, cranberry and grape seed extracts elicited differential effects on cell adhesion, cell morphology, and cell cycle regulatory pathways. This study represents one of the first comparative investigations of cranberry and grape seed extracts and their anti-proliferative effects on oral cancers. Previous findings using purified proanthocyanidin from grape seed extract demonstrated more prominent growth inhibition, as well as apoptosis-inducing, properties on CAL27 cells. These observations provide evidence that cranberry and grape seed extracts not only inhibit oral cancer proliferation but also that the mechanism of this inhibition may function by triggering key apoptotic regulators in these cell lines. This information will be of benefit to researchers interested in elucidating which dietary components are central to mechanisms involved in the mediation of oral carcinogenesis and progression