Rationale and Objectives: To prospectively evaluate perfusion computed tomography (CT) for assessment of changes in tumor vascularity after chemoradiation therapy (CRT) in locally advanced rectal cancer and to analyze the correlation between baseline perfusion parameters and tumor response.
Materials and Methods:Twenty patients with rectal cancer underwent baseline perfusion CT before CRT, and in 11 an examination after CRT was also performed. For each tumor, blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface area product (PS) were quantified. The Mann-Whitney U test compared baseline perfusion parameters of responders and nonresponders and pre-and post-CRT measurements were compared by the Wilcoxon signed-rank test (P < .05 statistically significant for both tests).Results: Baseline BF was significantly lower (P = .013) and MTT was significantly higher (P = .006) in responders. Both were able to discriminate responders from nonresponders with a sensitivity of 80% and 100% and a specificity of 73.3% and 86.7%, respectively, for BF and MTT. Baseline BV and PS were not significantly different in responders and nonresponders. Perfusion parameters changed significantly in post-CRT scans compared to baseline: BF (P = .003), BV (P = .003), and PS (P = .008) decreased, whereas MTT increased (P = .006).Conclusion: Baseline BF and MTT can discriminate patients with a favorable response from those that fail to respond to CRT, potentially selecting high-risk patients with resistant tumors that may benefit from an aggressive preoperative treatment approach.
Introduction
Exercise-based cardiac rehabilitation (EBCR) is part of the management of patients who have suffered an acute myocardial infarction (AMI). Patients with a reduced ejection fraction (EF) comprise a higher-risk subgroup and are referred less often for these programmes. This study aimed at assessing the impact of the baseline EF on the functional benefits, as assessed by peak oxygen uptake (pVO
2
) and exercise duration, of an EBCR programme in AMI survivors.
Methods
Observational, retrospective cohort study including all patients admitted to a tertiary centre due to an AMI who completed a phase II EBCR programme after discharge, between November 2012 and April 2017. Functional parameters were assessed by a symptom-limited cardiopulmonary exercise test.
Results
A total of 379 patients were included [40.9% with reduced EF (<50%) at discharge]. After the programme, pVO
2
and exercise duration increased significantly (
p
< 0.001). Patients with a reduced EF had a lower pVO
2
and completed a shorter duration of exercise at the beginning and end of the programme. This group presented a higher increase in pVO
2
(
p
= 0.001) and exercise duration (
p
= 0.007). This was maintained after adjusting for age, gender, history of coronary artery disease, number of sessions, Killip classification, arterial hypertension, dyslipidaemia, diabetes mellitus, smoking status and baseline pVO
2
.
Conclusion
A phase II EBCR programme was associated with significant improvements in pVO
2
and exercise duration among AMI survivors, irrespective of baseline EF classification. Those with a reduced baseline EF derived an even greater improvement, highlighting the importance of EBCR in this subgroup of patients.
The article delves into the potential application of space syntax methodology to landscape architecture. Anticipating the complexity of the landscape architectural design process, the use of 3D space syntax analysis made it possible to better understand the relations between urban space shapes and their functions. The application of an iterative process of project improvement optimizes the fulfilment of the landscape architect vision, through changes in ground shaping, selection of tree species and their spatial distribution. This article explores the vegetation attributes of vegetation that are necessary to consider in landscape architecture projects in the context of the DepthSpace 3D software, using the case study of an urban park in Maia—Portugal. To achieve this, it was necessary to define the attributes to be inserted in the software. The main attributes of vegetation that can be employed in landscape architecture projects are form and dimension, growth speed, and visual permeability (opacity) of the crown in winter and summer. The software proved itself a useful tool, not only in studying and evaluating the effects of the final design, but also during project development.
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