Unification of favourable intermediate‐, unfavourable intermediate‐, and very high‐risk stratification criteria for prostate cancer

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139069/1/bju13903.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139069/2/bju13903_am.pd

Quantification of collagen organization in histopathology samples using liquid crystal based polarization microscopy

Author Posting. © The Optical Society, 2017. This article is posted here by permission of The Optical Society for personal use, not for redistribution. The definitive version was published in Biomedical Optics Express 8 (2017): 4243-4256, doi:10.1364/BOE.8.004243.A number of histopathology studies have utilized the label free microscopy method of Second Harmonic Generation (SHG) to investigate collagen organization in disease onset and progression. Here we explored an alternative label free imaging approach, LC-PolScope that is based on liquid crystal based polarized light imaging. We demonstrated that this more accessible technology has the ability to visualize all fibers of interest and has a good to excellent correlation between SHG and LC-PolScope measurements in fibrillar collagen orientation and alignment. This study supports that LC-PolScope is a viable alternative to SHG for label free collagen organization measurements in thin histology sections.Morgridge Institute for Research and National Institutes of Health (NIH) (U54DK104310 and R01GM114274); The University of Wisconsin Carbone Cancer Center Cancer Center Biocore and Histology core (UWCCC) (P30 CA014520)

How open science helps researchers succeed

Open access, open data, open source, and other open scholarship practices are growing in popularity and necessity. However, widespread adoption of these practices has not yet been achieved. One reason is that researchers are uncertain about how sharing their work will affect their careers. We review literature demonstrating that open research is associated with increases in citations, media attention, potential collaborators, job opportunities, and funding opportunities. These findings are evidence that open research practices bring significant benefits to researchers relative to more traditional closed practices

Pharmacokinetics of Ferumoxytol in the Abdomen and Pelvis: A Dosing Study with 1.5- and 3.0-T MRI Relaxometry

Background The off-label use of ferumoxytol (FE), an intravenous iron preparation for iron deficiency anemia, as a contrast agent for MRI is increasing; therefore, it is critical to understand its pharmacokinetics. Purpose To evaluate the pharmacokinetics of FE in the abdomen and pelvis, as assessed with quantitative 1.5- and 3.0-T MRI relaxometry. Materials and Methods R2*, an MRI technique used to estimate tissue iron content in the abdomen and pelvis, was performed at 1.5 and 3.0 T in 12 healthy volunteers between April 2015 and January 2016. Volunteers were randomly assigned to receive an FE dose of 2 mg per kilogram of body weight (FE$_{2mg}$) or 4 mg/kg (FE$_{4mg}$). MRI was repeated at 1.5 and 3.0 T for each volunteer at five time points: days 1, 2, 4, 7, and 30. A radiologist experienced in MRI relaxometry measured R2* in organs of the mononuclear phagocyte system (MPS) (ie, liver, spleen, and bone marrow), non-MPS anatomy (kidney, pancreas, and muscle), inguinal lymph nodes (LNs), and blood pool. A paired Student t test was used to compare changes in tissue R2*. Results Volunteers (six female; mean age, 44.3 years ± 12.2 [standard deviation]) received either FE$_{2 mg}$ (n = 5) or FE$_{4 mg}$ (n = 6). Overall R2* trend analysis was temporally significant (P < .001). Time to peak R2* in the MPS occurred on day 1 for FE$_{2mg}$ and between days 1 and 4 for FE$_{4mg}$ (P < .001 to P < .002). Time to peak R2* in non-MPS anatomy, LNs, and blood pool occurred on day 1 for both doses (P < .001 to P < .09). Except for the spleen (at 1.5 T) and liver, MPS R2* remained elevated through day 30 for both doses (P = .02 to P = .03). Except for the kidney and pancreas, non-MPS, LN, and blood pool R2* returned to baseline levels between days 2 and 4 at FE$_{2mg}$ (P = .06 to P = .49) and between days 4 and 7 at FE$_{4mg}$ (P = .06 to P = .63). There was no difference in R2* change between non-MPS and LN R2* at any time (range, 1-71 sec$^{-1}$ vs 0-50 sec$^{-1}$; P = .06 to P = .97). Conclusion The pharmacokinetics of ferumoxytol in lymph nodes are distinct from those in mononuclear phagocyte system (MPS) organs, parallel non-MPS anatomy, and the blood pool. © RSNA, 2019 Online supplemental material is available for this article

Quantitating whole lesion tumor biology in rectal cancer MRI: taking a lesson from FDG-PET tumor metrics

PURPOSE To determine the value of novel whole tumor metrics in DWI-MRI and DCE-MRI of rectal cancer treatment assessment. MATERIALS AND METHODS This retrospective study included 24 uniformly treated patients with rectal adenocarcinoma who underwent MRI including diffusion-weighted (DW) and dynamic contrast-enhanced (DCE) sequences, before and after chemoradiotherapy. Two experienced readers independently measured tumor volume and apparent diffusion coefficient (ADC) on DWI-MRI and tumor volume and transfer constant K on DCE-MRI. In addition, we explored and defined Total Lesion Diffusion (TLD) as Total DWI tumor volume multiplied by mean volumetric ADC and Total Lesion Perfusion (TLP) as the total DCE tumor volume multiplied by the mean volumetric K . These metrics were correlated with histopathologic percent tumor regression in the resected specimen (%TR). Inter-reader agreement was assessed using the concordance correlation coefficient (CCC). RESULTS For both readers, post-treatment TLP revealed comparable correlations with %TR compared with K (reader 1; Spearman's rho = - 0.36 vs. - 0.32, reader 2; Spearman's rho = - 0.32 vs. - 0.28). In addition, TLP afforded the highest inter-reader agreement at post-treatment among TLP, DCE vol, and K (CCC: 0.64 vs. 0.36 vs. 0.35). Post-treatment TLD showed similar correlation with %TR as DWI volume in reader 1 and superior correlation with %TR for reader 2 (reader 1; Spearman's rho - 0.56 vs. - 0.57, reader 2; Spearman's rho - 0.59 vs. - 0.45). CONCLUSION The novel tumor metrics TLD and TLP revealed similar results to established metrics for correlation with tumor response with equivalent or superior inter-reader agreements and we recommend that these be studied in larger trials

Combined gadoxetic acid and gadobenate dimeglumine enhanced liver MRI: a parameter optimization study

PURPOSE To demonstrate the feasibility of combined delayed-phase gadoxetic acid (GA) and gadobenate dimeglumine (GD) enhanced liver MRI for improved detection of liver metastases, and to optimize contrast agent dose, timing, and flip angle (FA). METHODS Fourteen healthy volunteers underwent liver MRI at 3.0T at two visits during which they received two consecutive injections: 1. GA (Visit 1 = 0.025 mmol/kg; Visit 2 = 0.05 mmol/kg) and 2. GD (both visits = 0.1 mmol/kg) 20 min after GA administration. Two sub-studies were performed: Experiment-1 Eight subjects underwent multi-phase breath-held 3D-fat-saturated T1-weighted spoiled gradient echo (SGRE) imaging to determine the optimal imaging window for the combined GA + GD protocol to create a homogeneously hyperintense liver and vasculature ("plain-white-liver") with maximum contrast to muscle which served as a surrogate for metastatic lesions in both experiments. Experiment-2 Six subjects underwent breath-held 3D-fat-saturated T1-weighted SGRE imaging at three different FA to determine the optimal FA for best image contrast. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were evaluated. RESULTS Experiment-1 The combined GA + GD protocol created a homogeneously hyperintense liver and vasculature with maximum CNR liver/muscle at approximately 60-120 s after automatic GD-bolus detection. Experiment-2 Flip angles between 25° and 35° at a dose of 0.025 mmol/kg GA provided the best combination that minimized liver/vasculature CNR, while maximizing liver/muscle CNR. CNR performance to achieve a "plain-white-liver" was superior with 0.025 mmol/kg GA compared to 0.05 mmol/kg. CONCLUSION Combined GA + GD enhanced T1-weighted MRI is feasible to achieve a homogeneously "plain-white-liver". Future studies need to confirm that this protocol can improve sensitivity of liver lesion detection in patients with metastatic liver disease

The Effect of High-Stakes Rewards on Performance in High-Stress Situations

An article that appeared in JASS, issue 2016Studies have shown that when individuals are motivated - either externally or internally - to complete a task, their respective performance increases relative to the non-reward groups. However, few studies have looked at the effect of introducing rewards while participants are under stressful stimuli and the effect that this may potentially have on performance and physiological parameters. To study this, we used two different groups of participants, one that was offered a high-quality reward and the other a control with no knowledge of any reward. Participants were put under a four-and-a-half-minute time restraint to read a passage and a subsequent 90-second time constraint to answer seventeen multiple choice questions about the passage. We hypothesized that the introduction of the high-quality reward would negatively affect performance which would be seen physiologically by an increased heart rate, blood pressure, and respiration rate after the introduction of the high-quality reward. This in turn would negatively alter their overall exam performance. The results displayed a statistically significant increase in heart rate between the reward and nonreward groups; however, a significant increase was not observed in mean arterial pressure or respiration rates. The average test scores between the reward and non-reward group also did not demonstrate a statistical significance. Our results demonstrate that stress physiological parameters may increase from the introduction of high rewards and overall this may increase test performance. However, further studies are needed to test more participants and narrow potential external variables that may affect these results