Corrigendum to "Chemical apportionment of southern African aerosol mass and optical depth" published in Atmos. Chem. Phys., 9, 7643–7655, 2009

A correction to results by Magi (2009) is presented here. By combining the in situ measurements of speciated aerosol mass concentrations with concurrent measurements of total aerosol optical properties at a wavelength of 550 nm, it is shown that ~66 % of scattering is due to carbonaceous aerosol, where derived mass scattering cross sections (MSC) for OC and BC are 3.8 ± 0.5 m<sup>2</sup> g<sup>−1</sup> and 2.9 ± 0.8 m<sup>2</sup> g<sup>−1</sup>, respectively. Derived values of mass absorption cross sections (MAC) for OC and BC are 0.7 ± 0.2 m<sup>2</sup> g<sup>−1</sup> and 12.1 ± 0.8 m<sup>2</sup> g<sup>−1</sup>, respectively. The values of MAC imply that ~21 % of the mid-visible aerosol absorption in southern Africa is due to OC, with the remainder due to BC. SSA for BC and OC are about the same as Magi (2009). The results here are determined using an approach that accounts for the fact that OC and BC are partially scattering and absorbing

Occurrence of exocrine pancreatic insufficiency in patients with advanced neuroendocrine tumors treated with somatostatin analogs

Background: Although exocrine pancreatic insufficiency (EPI) has been described in patients with neuroendocrine neoplasia (NEN) treated with somatostatin analogs (SSAs), its role in the therapeutic management of these patients is not well established. Aim: To determine the frequency of EPI in patients with NEN long-term treated with SSAs. Methods: This is a prospective single-center study evaluating 35 patients treated with SSAs for >12 months due to unresectable/advanced nonpancreatic well-differentiated NEN. Clinical evaluation, biochemical parameters, and fecal elastases 1 (FE-1) were assessed to diagnose EPI. Results: A total of 7 patients (20%) had EPI, given the presence of abdominal symptoms and a median FE-1 value of 180 mcg/g stool (150–198). No patient had severe EPI, defined as FE-1 < 100 mcg/g stool. Elevated glycated Hb levels were a significant predictor for developing EPI (OR 4.81, p = 0.01). No significant difference in terms of duration of SSA treatment was observed between patients with or without EPI diagnosed (84 months and 72 months, respectively; p = 0.950). Conclusions: Mild-moderate EPI is a relatively common condition in patients receiving long-term treatment with SSAs. Specific clinical and biochemical evaluations, including FE-1, should be planned in these patients to diagnose this relevant condition early, which may deteriorate quality of life and cause malnutrition

Carotid artery disease: Novel pathophysiological mechanisms identified by gene-expression profiling of peripheral blood

AbstractObjectThe pathogenesis of carotid artery stenosis (CAS) as well as the mechanisms underlying the different localisation of the atherosclerotic lesions remains poorly understood. We used microarray technology to identify novel systemic mediators that could contribute to CAS pathogenesis.Moreover, we compared gene-expression profile of CAS with that of patients affected by abdominal aortic aneurysm (AAA), previously published by our group.Methods and resultsBy global gene-expression profiling in a pool of 10 CAS patients and 10 matched controls, we found 82 genes differentially expressed. Validation study in pools used for profiling and replication study in larger numbers of CAS patients (n = 40) and controls (n = 40) of 14 genes by real-time polymerase chain reaction (RT-PCR) confirmed microarray results. Fourteen out of 82 genes were similarly expressed in AAA patients. Gene ontology analysis identified a statistically significant enrichment in CAS of differentially expressed transcripts involved in immune response and oxygen transport. Whereas alteration of oxygen transport is a common tract of the two localisations, alteration of immune response in CAS and of lipid metabolic process in AAA represents distinctive tracts of the two atherosclerotic diseases.ConclusionsWe describe the systemic gene-expression profile of CAS, which provides an extensive list of potential molecular markers

Chalcogenide Glasses for All-optical Processing

Copyright © 2006 IEEEChalcogenide glasses, which contain S, Se or Te atoms combined with network forming elements such as Ge, As, Sb have the largest third order optical nonlinearity of any inorganic glass. As a result they are attractive candidates for fibre and waveguide devices for all-optical signal processing in the telecommunications bands. In this talk I will review our recent progress in all-optical devices such as regenerators, wavelength converters and other devices in chalcogenide glasses.B. Luther-Davies, S. J. Madden, D-Y Choi, R-P Wang, A. V. Rode, A. Prasad, R. A. Jarvis, D. Moss, B. Eggleton, C. Grillet, M. R. E. Lamont, E. Magi, V. Ta’eed, M. Shookooh-Saremi, N. Baker, I. Littler, L. Fu, M. Rochette, Y. Rua

An evaluation of different meta-analysis approaches in the presence of allelic heterogeneity

Meta-analysis has proven a useful tool in genetic association studies. Allelic heterogeneity can arise from ethnic background differences across populations being meta-analyzed (for example, in search of common frequency variants through genome-wide association studies), and through the presence of multiple low frequency and rare associated variants in the same functional unit of interest (for example, within a gene or a regulatory region). The latter challenge will be increasingly relevant in whole-genome and whole-exome sequencing studies investigating association with complex traits. Here, we evaluate the performance of different approaches to meta-analysis in the presence of allelic heterogeneity. We simulate allelic heterogeneity scenarios in three populations and examine the performance of current approaches to the analysis of these data. We show that current approaches can detect only a small fraction of common frequency causal variants. We also find that for low-frequency variants with large effects (odds ratios 2–3), single-point tests have high power, but also high false-positive rates. P-value based meta-analysis of summary results from allele-matching locus-wide tests outperforms collapsing approaches. We conclude that current strategies for the combination of genetic association data in the presence of allelic heterogeneity are insufficiently powered

FastTagger: an efficient algorithm for genome-wide tag SNP selection using multi-marker linkage disequilibrium

<p>Abstract</p> <p>Background</p> <p>Human genome contains millions of common single nucleotide polymorphisms (SNPs) and these SNPs play an important role in understanding the association between genetic variations and human diseases. Many SNPs show correlated genotypes, or linkage disequilibrium (LD), thus it is not necessary to genotype all SNPs for association study. Many algorithms have been developed to find a small subset of SNPs called tag SNPs that are sufficient to infer all the other SNPs. Algorithms based on the <it>r</it>²LD statistic have gained popularity because <it>r</it>²is directly related to statistical power to detect disease associations. Most of existing <it>r</it>²based algorithms use pairwise LD. Recent studies show that multi-marker LD can help further reduce the number of tag SNPs. However, existing tag SNP selection algorithms based on multi-marker LD are both time-consuming and memory-consuming. They cannot work on chromosomes containing more than 100 k SNPs using length-3 tagging rules.</p> <p>Results</p> <p>We propose an efficient algorithm called FastTagger to calculate multi-marker tagging rules and select tag SNPs based on multi-marker LD. FastTagger uses several techniques to reduce running time and memory consumption. Our experiment results show that FastTagger is several times faster than existing multi-marker based tag SNP selection algorithms, and it consumes much less memory at the same time. As a result, FastTagger can work on chromosomes containing more than 100 k SNPs using length-3 tagging rules.</p> <p>FastTagger also produces smaller sets of tag SNPs than existing multi-marker based algorithms, and the reduction ratio ranges from 3%-9% when length-3 tagging rules are used. The generated tagging rules can also be used for genotype imputation. We studied the prediction accuracy of individual rules, and the average accuracy is above 96% when <it>r</it>²≥ 0.9.</p> <p>Conclusions</p> <p>Generating multi-marker tagging rules is a computation intensive task, and it is the bottleneck of existing multi-marker based tag SNP selection methods. FastTagger is a practical and scalable algorithm to solve this problem.</p

Treatment challenges in and outside a specialist network setting: Pancreatic neuroendocrine tumours

Pancreatic Neuroendocrine Neoplasms comprise a group of rare tumours with special biology, an often indolent behaviour and particular diagnostic and therapeutic requirements. The specialized biochemical tests and radiological investigations, the complexity of surgical options and the variety of medical treatments that require individual tailoring, mandate a multidisciplinary approach that can be optimally achieved through an organized network. The present study describes currents concepts in the management of these tumours as well as an insight into the challenges of delivering the pathway in and outside a Network

Testicular germ-cell tumours and penile squamous cell carcinoma: Appropriate management makes the difference

Germ-cell tumours (GCT) of the testis and penile squamous cell carcinoma (PeSCC) are a rare and a very rare uro-genital cancers, respectively. Both tumours are well defined entities in terms of management, where specific recommendations - in the form of continuously up-to-dated guide lines-are provided. Impact of these tumour is relevant. Testicular GCT affects young, healthy men at the beginning of their adult life. PeSCC affects older men, but a proportion of these patients are young and the personal consequences of the disease may be devastating. Deviation from recommended management may be a reason of a significant prognostic worsening, as proper treatment favourably impacts on these tumours, dramatically on GCT and significantly on PeSCC. RARECAREnet data may permit to analyse how survivals may vary according to geographical areas, histology and age, leading to assume that non-homogeneous health-care resources may impact the cure and definitive outcomes. In support of this hypothesis, some epidemiologic datasets and clinical findings would indicate that survival may improve when appropriate treatments are delivered, linked to a different accessibility to the best health institutions, as a consequence of geographical, cultural and economic barriers. Finally, strong clues based on epidemiological and clinical data support the hypothesis that treatment delivered at reference centres or under the aegis of a qualified multi-institutional network is associated with a better prognosis of patients with these malignancies. The ERN EURACAN represents the best current European effort to answer this clinical need

Treatment challenges in and outside a network setting: Head and neck cancers

Head and neck cancer (HNC) is a rare disease that can affect different sites and is characterized by variable incidence and 5-year survival rates across Europe. Multiple factors need to be considered when choosing the most appropriate treatment for HNC patients, such as age, comorbidities, social issues, and especially whether to prefer surgery or radiation-based protocols. Given the complexity of this scenario, the creation of a highly specialized multidisciplinary team is recommended to guarantee the best oncological outcome and prevent or adequately treat any adverse effect. Data from literature suggest that the multidisciplinary team-based approach is beneficial for HNC patients and lead to improved survival rates. This result is likely due to improved diagnostic and staging accuracy, a more efficacious therapeutic approach and enhanced communication across disciplines. Despite the benefit of MTD, it must be noted that this approach requires considerable time, effort and financial resources and is usually more frequent in highly organized and high-volume centers. Literature data on clinical research suggest that patients treated in high-accrual centers report better treatment outcomes compared to patients treated in low-volume centers, where a lower radiotherapy-compliance and worst overall survival have been reported. There is general agreement that treatment of rare cancers such as HNC should be concentrated in high volume, specialized and multidisciplinary centers. In order to achieve this goal, the creation of international collaboration network is fundamental. The European Reference Networks for example aim to create an international virtual advisory board, whose objectives are the exchange of expertise, training, clinical collaboration and the reduction of disparities and enhancement of rationalize migration across Europe. The purpose of our work is to review all aspects and challenges in and outside this network setting planned for the management of HNC patients