Determining Rheumatology Patient Interest in a Group Strength Training Program - Results of an Exercise Survey.

BACKGROUND: Exercise has proven benefits in rheumatologic disease including reducing inflammation and improving symptoms. A Group Strength Training (GST) program design has improved adherence to exercise in primary care patients but the effect is unknown in rheumatology patients. We examined the interest of rheumatology patients with different diagnoses and the effect of comorbidities in pursuing an organized GST program. METHODS: We conducted a cross-sectional survey of patients from a rheumatology practice in central Pennsylvania in February and April 2017. This survey assessed self-reported interest of patients in a GST program in addition to demographics, comorbidities, and quality of life measures. Primary care data from a previous survey were used for comparative analysis for the primary outcome: interest in a GST program. RESULTS: Fifty percent of rheumatology patients were interested in a GST program and there was no difference of interest compared to primary care patients (X2 = 2.04, p = 0.15). There was no difference in interest in a GST program for rheumatology patients with poor health compared to patients with good health (OR = 0.9, p = 0.8). Female patients were more interested in a group strength training program than male patients (OR = 3.7, p = 0.001). Patients with a BMI of 25-30 (OR = 2.2, p = 0.04) or > 30 (OR = 1.7, p = 0.12) were more interested compared to those with a normal BMI. There was no difference in interest in group strength training regardless of rheumatology diagnosis or comorbidities. CONCLUSION: Our data suggest that rheumatology patients are interested in a GST program regardless of disease, medical comorbidities, perceived mental or physical health, or education level. Further study is needed to determine the effects of GST on rheumatologic diseases.

Multiscale and multi-modality visualization of angiogenesis in a human breast cancer model.

Angiogenesis in breast cancer helps fulfill the metabolic demands of the progressing tumor and plays a critical role in tumor metastasis. Therefore, various imaging modalities have been used to characterize tumor angiogenesis. While micro-CT (µCT) is a powerful tool for analyzing the tumor microvascular architecture at micron-scale resolution, magnetic resonance imaging (MRI) with its sub-millimeter resolution is useful for obtaining in vivo vascular data (e.g. tumor blood volume and vessel size index). However, integration of these microscopic and macroscopic angiogenesis data across spatial resolutions remains challenging. Here we demonstrate the feasibility of 'multiscale' angiogenesis imaging in a human breast cancer model, wherein we bridge the resolution gap between ex vivo µCT and in vivo MRI using intermediate resolution ex vivo MR microscopy (µMRI). To achieve this integration, we developed suitable vessel segmentation techniques for the ex vivo imaging data and co-registered the vascular data from all three imaging modalities. We showcase two applications of this multiscale, multi-modality imaging approach: (1) creation of co-registered maps of vascular volume from three independent imaging modalities, and (2) visualization of differences in tumor vasculature between viable and necrotic tumor regions by integrating µCT vascular data with tumor cellularity data obtained using diffusion-weighted MRI. Collectively, these results demonstrate the utility of 'mesoscopic' resolution µMRI for integrating macroscopic in vivo MRI data and microscopic µCT data. Although focused on the breast tumor xenograft vasculature, our imaging platform could be extended to include additional data types for a detailed characterization of the tumor microenvironment and computational systems biology applications.

Assessing breast cancer angiogenesis in vivo: which susceptibility contrast MRI biomarkers are relevant?

PURPOSE: There is an impending need for noninvasive biomarkers of breast cancer angiogenesis to evaluate the efficacy of new anti-angiogenic therapies in vivo. The purpose of this study was to systematically evaluate the sensitivity of in vivo steady-state susceptibility contrast-MRI biomarkers of angiogenesis in a human breast cancer model. METHODS: Orthotopic MDA-MB-231 human breast cancer xenografts were imaged by steady-state susceptibility contrast-MRI at post-inoculation week 3 and post-inoculation week 5, followed by ex vivo whole tumor 3D micro-CT angiography. "Absolute" (i.e., measures of vascular morphology in appropriate units) and "relative" (i.e., proportional to measures of vascular morphology) MRI biomarkers of tumor blood volume, vessel size, and vessel density were computed and their ability to predict the corresponding micro-CT analogs assessed using cross-validation analysis. RESULTS: All MRI biomarkers significantly correlated with their micro-CT analogs and were sensitive to the micro-CT-measured decreases in tumor blood volume and vessel density from post-inoculation week 3 to post-inoculation week 5. However, cross-validation analysis revealed there was no significant difference between the predictive accuracy of "absolute" and "relative" biomarkers. CONCLUSION: As "relative" biomarkers are more easily computed from steady-state susceptibility contrast-MRI (i.e., without additional MRI measurements) than "absolute" biomarkers, it makes them promising candidates for assessing breast cancer angiogenesis in vivo.

In vivo laser speckle imaging reveals microvascular remodeling and hemodynamic changes during wound healing angiogenesis.

Laser speckle contrast imaging (LSCI) is a high-resolution and high contrast optical imaging technique often used to characterize hemodynamic changes in short-term physiological experiments. In this study, we demonstrate the utility of LSCI for characterizing microvascular remodeling and hemodynamic changes during wound healing angiogenesis in vivo. A 2 mm diameter hole was made in the mouse ear and the periphery of the wound imaged in vivo using LSCI over 12 days. We were able to visualize and quantify the vascular and perfusion changes that accompanied wound healing in the microenvironment proximal to the wound, and validated these changes with histology. We found that consistent with the stages of wound healing, microvessel density increased during the initial inflammatory phase (i.e., day 0-3), stayed elevated through the tissue formation phase (i.e., until day 7) and returned to baseline during the tissue remodeling phase (i.e., by day 12). Concomitant "wide area mapping" of blood flow revealed that tissue perfusion in the wound periphery initially decreased, gradually increased from day 3-7, and subsided as healing completed. Interestingly, some regions exhibited a reestablishment of tissue perfusion approximately 6 days earlier than the ~18 days usually reported for the long term remodeling phase. The results from this study demonstrate that LSCI is an ideal platform for elucidating in vivo changes in microvascular hemodynamics and angiogenesis, and has the potential to offer invaluable insights in a range of disease models involving abnormal hemodynamics, such as diabetes and tumors.