Thermodynamic entropy as an indicator for urban sustainability?

As foci of economic activity, resource consumption, and the production of material waste and pollution, cities represent both a major hurdle and yet also a source of great potential for achieving the goal of sustainability. Motivated by the desire to better understand and measure sustainability in quantitative terms we explore the applicability of thermodynamic entropy to urban systems as a tool for evaluating sustainability. Having comprehensively reviewed the application of thermodynamic entropy to urban systems we argue that the role it can hope to play in characterising sustainability is limited. We show that thermodynamic entropy may be considered as a measure of energy efficiency, but must be complimented by other indices to form part of a broader measure of urban sustainability

DAPK Promoter Methylation and Bladder Cancer Risk: A Systematic Review and Meta-Analysis

<div><p>Background</p><p>Methylation of tumor suppressor gene promoter leads to transcription inactivation and is involved in tumorigenesis. Several studies demonstrate a potential association between the Death-Associated Protein Kinase (DAPK) gene promoter methylation and bladder cancer risk, tumor stage and histological grade. Due to inconsistent results of these studies, we performed this meta-analysis to ascertain the association.</p><p>Methods</p><p>Studies were retrieved from the PubMed, Embase, Web of Science and the Cochrane Library databases. Study selection and data extraction were executed by two reviewers independently. Meta-analysis was performed using Stata 13.0 and Review Manager 5.3 software.</p><p>Results</p><p>A total of 21 articles involving 15 case control and 8 case series studies were included in this meta-analysis. DAPK promoter methylation was associated with bladder cancer risk (OR: 5.81; 95%CI = 3.83–8.82, P<0.00001). The frequency of DAPK promoter methylation was equal in bladder cancer tissue and paired adjacent normal tissue (OR: 0.87; 95%CI = 0.31–2.48, P = 0.794). Furthermore, DAPK promoter methylation was associated with higher histological grade (OR: 1.52; 95%CI = 1.10–2.09, P = 0.011) but not associated with tumor stage (OR: 1.12; 95%CI = 0.67–1.87, P = 0.668).</p><p>Conclusions</p><p>The result suggests that DAPK promoter methylation is significantly increased in bladder cancer patients compared to normal controls. DAPK promoter methylation could serve as a biomarker for bladder cancer detection and management.</p></div

The pooled OR from 15 studies including 1,247 samples form BCa patients and 405 from normal controls.

<p>OR: 5.81; 95%CI = 3.83–8.82, P<0.00001.</p

Sensitivity analysis from 15 studies comparing DAPK promoter methylation in BCa patients and normal controls.

<p>Sensitivity analysis from 15 studies comparing DAPK promoter methylation in BCa patients and normal controls.</p

The pooled OR from 5 studies including 223 paired BCa tumor tissue and adjacent normal bladder tissue.

<p>OR: 0.87; 95%CI = 0.31–2.48, P = 0.794.</p

Characteristics of the Included Studies

<p>Characteristics of the Included Studies</p

Stratified analysis of the association between DAPK promoter methylation and bladder cancer risk

<p>Stratified analysis of the association between DAPK promoter methylation and bladder cancer risk</p

Kaplan-Meier estimate of 3-year survival for overall, cancer-specific, recurrence-free survival.

<p>Log-rank test indicates that overall survival, cancer specific survival and recurrence free survival among LRC and ORC groups are not significantly different.</p

The funnel plots were virtually symmetrical, suggesting there were no publication bias in this meta-analysis.

<p>(A)The funnel plot from 15 studies comparing DAPK promoter methylation in BCa patients and normal controls. (B)The funnel plot from 5 studies with paired BCa tissue and adjacent normal bladder tissue. (C)The funnel plot from 14 studies assessing the association between DAPK promoter methylation and tumor stage. (D)The funnel plot from 14 studies assessing the association between DAPK promoter methylation and histological grade.</p

Selection of studies in the meta-analysis.

<p>Selection of studies in the meta-analysis.</p