Understanding the Interaction Between Blood Flow and an Applied Magnetic Field

Hemodynamic monitoring is extremely important in the accurate measurement of vital parameters. Current methods are highly invasive or noncontinuous, and require direct access to the patient’s skin. This study intends to explore the modulated magnetic signature of blood method (MMSB) to attain blood flow information. This method uses an applied magnetic field to magnetize the iron in the red blood cells and measures the disturbance to the field with a magnetic sensor [1]. Exploration will be done by experimentally studying in-vitro, as well as simulating in COMSOL the alteration of magnetic fields induced by the flow of a magnetic solution. It was found that the variation in magnetic field is due to a high magnetization of blood during slow flow and low magnetization during rapid flow. The understanding of this phenomenon can be used in order to create a portable, non-invasive, continuous, and accurate sensor to monitor the cardiovascular system

Differential Mobility Spectrometry–Mass Spectrometry for Atomic Analysis

Analysis and separation of atomic ions within a portable setting are studied in forensic applications of radiological debris analysis. Ion mobility spectrometry (IMS) may be used to show separation of atomic ions, while the related method of differential mobility spectrometry (DMS) has focused on fractionation of primarily molecular components. We set out to investigate DMS as a means for separating atomic ions. We initially derived the differential ion mobility parameter, alpha, from classic empirical IMS data of atomic ions, cesium and potassium, each showing its own distinct form of alpha. These alpha functions were applied to DMS simulations and supported by analytical treatment that suggested a means for a rapid disambiguation of atomic ions using DMS. We validated this hypothesis through the prototype cesium–potassium system investigated experimentally by DMS coupled to mass spectrometry (MS). Such a feature would be advantageous in a field portable instrument for rapid atomic analyses especially in the case of isobaric ions that cannot be distinguished by MS. Herein, we first report this novel method for the derivation of alpha from existing field dependent drift tube ion mobility data. Further, we translate experimental DMS data into alpha parameters by expanding upon existing methods. Refining the alpha parameter in this manner helps convey the interpretation of the alpha parameter particularly for those new to the DMS field

Microfluidic Biopsy Trapping Device for the Real-Time Monitoring of Tumor Microenvironment

<div><p>The tumor microenvironment is composed of cellular and stromal components such as tumor cells, mesenchymal cells, immune cells, cancer associated fibroblasts and the supporting extracellular matrix. The tumor microenvironment provides crucial support for growth and progression of tumor cells and affects tumor response to therapeutic interventions. To better understand tumor biology and to develop effective cancer therapeutic agents it is important to develop preclinical platforms that can faithfully recapitulate the tumor microenvironment and the complex interaction between the tumor and its surrounding stromal elements. Drug studies performed in vitro with conventional two-dimensional cancer cell line models do not optimally represent clinical drug response as they lack true tumor heterogeneity and are often performed in static culture conditions lacking stromal tumor components that significantly influence the metabolic activity and proliferation of cells. Recent microfluidic approaches aim to overcome such obstacles with the use of cell lines derived in artificial three-dimensional supportive gels or micro-chambers. However, absence of a true tumor microenvironment and full interstitial flow, leads to less than optimal evaluation of tumor response to drug treatment. Here we report a continuous perfusion microfluidic device coupled with microscopy and image analysis for the assessment of drug effects on intact fresh tumor tissue. We have demonstrated that fine needle aspirate biopsies obtained from patient-derived xenograft models of adenocarcinoma of the lung can successfully be analyzed for their response to ex vivo drug treatment within this biopsy trapping microfluidic device, wherein a protein kinase C inhibitor, staurosporine, was used to assess tumor cell death as a proof of principle. This approach has the potential to study tumor tissue within its intact microenvironment to better understand tumor response to drug treatments and eventually to choose the most effective drug and drug combination for individual patients in a cost effective and timely manner.</p></div

Electronic catheter stethoscope

An electronic catheter stethoscope measures and analyzes acoustic fields and dynamic pressure variations in the gaseous or liquid fluid inside a conventional medical catheter that is positioned in a patient\u27s urologic, digestive, reproductive, cardiovascular, neurological or pulmonary system. Measurement transducers are installed in a housing connectable to multiple preselected medical catheters. The transducers detect bodily functions that are transmitted to the preselected catheter from within the body. The transducers, housing, electrical interface and signal processing electronics are positioned outside the body

Comparison of the calculated viability index of the tumor FNAB samples during 5 days of treatment.

<p>(A) Comparison of the mean averaged VI of negative control group and staurosporine treated group from the baseline over the 5 day exposure period with n = 18 within each group. The difference in means between each treatment group was statistically significant, except for the baseline. (B.1, B.3) A 3-dimensional view of a representative FNAB sample from the negative control group at day 1 and day 5 respectively. (B.2, B.4) Histogram of the relative intensity values across the negative control FNAB samples for day 1 and day 5, respectively. (C.1, C.3) A 3-dimensional view of a representative FNAB sample from the 50 μM staurosporine treated group at day 1 and day 5 respectively. (C.2, C.4) Histogram of the relative intensity values across the 50 μM staurosporine treated FNAB samples for day 1 and day 5 respectively.</p

Calcein AM dye validation and FNAB sample viability assessment.

<p>Calcein AM dye validation and FNAB sample viability assessment.</p

Microfluidic device design.

<p>(A) Exploded view of the device showing the main body made from PDMS containing the 1 mm diameter inlet and outlets punched for each of the 10 channels. The main body is then sealed to a 25 x 75 mm glass slide by plasma gas treatment. Tubing is inserted into each of the inlet and outlets of the device. (B) Fully assembled PDMS prototype. (C) Solid Works rendering of a channel in the device showing the central post arrangement used to trap each FNAB tissue sample. The channel is 10 mm long, 600 μm wide and 125 μm in height. Each post is 150 μm long, 75 μm wide and 125 μm in height.</p

Assessment of small molecule drug perfusion in a tumor FNA fragment using Doxorubicin HCL.

<p>(A) Drug perfusion after an 8-hour period showing distribution of drug indicated by green fluorescent intensity spatially similar throughout the FNAB tissue sample. (B) Drug perfusion after a 24-hour period showing intensity peaks spatially similar throughout the FNAB tissue sample and the formation of apoptotic bodies.</p

Evaluation of antibody perfusion through the tumor FNAB on device.

<p>(A) 10x Phase contrast image of FNAB sample in trap of device and 10x fluorescent z-axis images (z5, z7, z9, z11) 24 hours post the staining procedure using isotype control antibodies for both EpCAM (red-Cy5) and CD44 (green-FITC). (B) 10x Phase contrast image of FNAB sample in trap of device and 10x fluorescent z-axis images (z5, z7, z9, z11) 24 hours post the staining procedure using EpCAM (red-Cy5) and CD44 (green-FITC).</p