Genotype-renal function correlation in type 2 autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is a common Mendelian disorder that affects approximately 1 in 1000 live births. Mutations of two genes, PKD1 and PKD2, account for the disease in approximately 80 to 85% and 10 to 15% of the cases, respectively. Significant interfamilial and intrafamilial renal disease variability in ADPKD has been well documented. Locus heterogeneity is a major determinant for interfamilial disease variability (i.e., patients from PKD1-linked families have a significantly earlier onset of ESRD compared with patients from PKD2-linked families). More recently, two studies have suggested that allelic heterogeneity might influence renal disease severity. The current study examined the genotype-renal function correlation in 461 affected individuals from 71 ADPKD families with known PKD2 mutations. Fifty different mutations were identified in these families, spanning between exon 1 and 14 of PKD2. Most (94%) of these mutations were predicted to be inactivating. The renal outcomes of these patients, including the age of onset of end-stage renal disease (ESRD) and chronic renal failure (CRF; defined as creatinine clearance < or = 50 ml/min, calculated using the Cockroft and Gault formula), were analyzed. Of all the affected individuals clinically assessed, 117 (25.4%) had ESRD, 47 (10.2%) died without ESRD, 65 (14.0%) had CRF, and 232 (50.3%) had neither CRF nor ESRD at the last follow-up. Female patients, compared with male patients, had a later mean age of onset of ESRD (76.0 [95% CI, 73.8 to 78.1] versus 68.1 [95% CI, 66.0 to 70.2] yr) and CRF (72.5 [95% CI, 70.1 to 74.9] versus 63.7 [95% CI, 61.4 to 66.0] yr). Linear regression and renal survival analyses revealed that the location of PKD2 mutations did not influence the age of onset of ESRD. However, patients with splice site mutations appeared to have milder renal disease compared with patients with other mutation types (P < 0.04 by log rank test; adjusted for the gender effect). Considerable renal disease variability was also found among affected individuals with the same PKD2 mutations. This variability can confound the determination of allelic effects and supports the notion that additional genetic and/or environmental factors may modulate the renal disease severity in ADPKD

Incentive Regulation and Efficiency of Portuguese Port Authorities

In all European seaports, organisational efficiency forms a vital component of the activities to improve competitiveness in the market. As public enterprise entities, Portuguese seaports rely on government subsidies to meet their deficits. The policy of subsidisation is part of the regulatory procedures that are intended to provide incentives for increasing productive efficiency, thereby allowing seaports to share in the social gains from efficiency in the form of greater, or at least stable, employment and local development. In addition, the drive for greater efficiency is meant to assist the ports' preparation for some kind of privatisation. In this paper, we analyse the technical and allocative efficiencies of Portuguese seaport authorities in order to investigate if the state's policy is achieving its aims. We find that the results are, at best, mixed, leading us to conclude that the incentive regulation carried out by the government's regulatory body, the Maritime Port Agency, is not achieving its aims. Therefore, we propose a policy revision to enforce efficiency, based on a governance environment framework. Maritime Economics & Logistics (2003) 5, 55–69. doi:10.1057/palgrave.mel.9100060

Efficiency in European Seaports with DEA: Evidence from Greece and Portugal

In this paper, we compare the seaport efficiency of two European countries, Greece and Portugal, using data envelopment analysis (DEA). The international benchmarking procedure is implemented, in which the seaports in each country are compared against each other. The broader aim of this study is to seek out those best practices that will lead to improved performance in the context of European seaport policy. We rank the seaports according to their total productivity for the period 1998–2000. Economic implications arising from the study are considered. Maritime Economics & Logistics (2004) 6, 122–140. doi:10.1057/palgrave.mel.9100099

Ranking and causes of inefficiency of container seaports in South-Eastern Europe

Purpose: This paper aims at benchmarking, measuring and identifying major determinants of the technical efficiency of container seaports in the region of South-Eastern Europe, including the Italian ports which directly affect competition in the wider region of East Mediterranean Sea. Methods: The study employs both non-parametric (standard and super-efficiency DEA) models and bootstrapped parametric techniques to provide a more holistic approach and useful insight into the given problem. Results and conclusions: The results indicate the relatively low (below 50 %) average total technical efficiency of the container ports in the study region, which can be attributed to both the lack of managerial skills and scale effects. The findings can help to determine sources of port inefficiency by geographical location and size and adopt best practices to improve the operational performance of container ports. © 2012 The Author(s)

A Benchmark Analysis of Italian Seaports Using Data Envelopment Analysis

This paper uses data envelopment analysis to evaluate the performance of Italian seaports from 2002 to 2003, combining operational and financial variables. The paper evaluates how close the Italian seaports are to the frontier of best practices. Moreover, the paper also tests for the role played by size, containerisation and labour in the efficiency of the seaports analysed. The general conclusion is that the Italians seaports examined display relatively high efficiency. However, there are also some inefficient seaports in the sample analysed. Management implications are subsequently drawn. Maritime Economics & Logistics (2006) 8, 347–365. doi:10.1057/palgrave.mel.9100163