Preliminary Development and Evaluation of Fiber-Optic Chemical Sensors

This paper could be consider seminal in the Civil Engineering field as it describes the first application of these sensors to a complex durability and management issue. For this reason it is potentially controversial as it requires Civil Engineers to re-evaluate the nature and scale of durability testing.

Bevacizumab and rapamycin induce growth suppression in mouse models of hepatocellular carcinoma

Background/Aims: Hepatocellular carcinoma is a leading cause of global cancer mortality, with standard chemotherapy being minimally effective in prolonging survival. We investigated if combined targeting of vascular endothelial growth factor protein and expression might affect hepatocellular carcinoma growth and angiogenesis.

Development and characterization of 10 polymorphic microsatellite loci for the blue shark, Prionace glauca, and their cross shark-species amplification.

Ten polymorphic nuclear microsatellite loci were developed from a microsatellite enriched genomic library of the blue shark, Prionace glauca. The utility of these markers for genetic studies of this globally distributed, heavily exploited, oceanic predator was assessed by screening 120 specimens sampled from six locations throughout the species’ range. Both moderately and highly polymorphic marker loci were identified. Three to 35 alleles were found to be segregating per locus (mean 10.1) with observed heterozygosities ranging from 24 to 91%. Evaluation of the cross-species amplification of these markers across 18 additional shark species indicates that these microsatellites are potentially useful for genetic studies of other species of conservation concern.

Development and validation of a fast monoclonal based disequilibrium enzyme-linked immunosorbent assay for the detection of triphenylmethane dyes and their metabolites in fish

Malachite Green (MG), Crystal Violet (CV) and Brilliant Green (BC) are antibacterial, antifungal and antiparasitic agents that have been used for treatment and prevention of diseases in fish. These dyes are metabolized into reduced leuco forms (LMG, LCV, LBG) that can be present in fish muscles for a long period. Due to the carcinogenic properties they are banned for use in fish for human consumption in many countries including the European Union and the United States. HPLC and LC-MS techniques are generally used for the detection of these compounds and their metabolites in fish. This study presents the development of a fast enzyme-linked immunosorbent assay (ELISA) method as an alternative for screening purposes. A first monoclonal cell line producing antibodies to MG was generated using a hybridoma technique. The antibody had good cross-reactivates with related chromatic forms of triphenylmethane dyes such as CV, BC, Methyl Green, Methyl Violet and Victoria Blue R. The monoclonal antibody (mAb) was used to develop a fast (20 min) disequilibrium ELISA screening method for the detection of triphenylmethanes in fish. By introducing an oxidation step with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) during sample extraction the assay was also used to detect the presence of the reduced metabolites of triphenylmethanes. The detection capability of the assay was 1 ng g(-1) for MG, LMG, CV, LCV and BC which was below the minimum required performance limit (MRPL) for the detection method of total MG (sum of MG and LMG) set by the Commission Decision 2004/25/EC (2 ng g(-1)). The mean recoveries for fish samples spiked at 0.5 MRPL and MRPL levels with MG and LMG were between 74.9 and 117.0% and inter- and intra-assay coefficients of variation between 4.7 and 25.7%. The validated method allows the analysis of a batch of 20 samples in two to three hours. Additionally, this procedure is substantially faster than other ELISA methods developed for MG/LMG thus far. The stable and efficient monoclonal cell line obtained is an unlimited source of sensitive and specific antibody to MG and other triphenylmethanes. (C) 2011 Elsevier B.V. All rights reserved.

Development and clinical validation of multiplex TaqMan® assays for rapid diagnosis of viral gastroenteritis.

There is a need to provide rapid, sensitive, and often high throughput detection of pathogens in diagnostic virology. Viral gastroenteritis is a serious health issue often leading to hospitalization in the young, the immunocompromised and the elderly. The common causes of viral gastroenteritis include rotavirus, norovirus (genogroups I and II), astrovirus, and group F adenoviruses (serotypes 40 and 41). This article describes the work-up of two internally controlled multiplex, probe-based PCR assays and reports on the clinical validation over a 3-year period, March 2007 to February 2010. Multiplex assays were developed using a combination of TaqMan™ and minor groove binder (MGB™) hydrolysis probes. The assays were validated using a panel of 137 specimens, previously positive via a nested gel-based assay. The assays had improved sensitivity for adenovirus, rotavirus, and norovirus (97.3% vs. 86.1%, 100% vs. 87.8%, and 95.1% vs. 79.5%, respectively) and also more specific for targets adenovirus, rotavirus, and norovirus (99% vs. 95.2%, 100% vs. 93.6%, and 97.9% vs. 92.3%, respectively). For the specimens tested, both assays had equal sensitivity and specificity for astrovirus (100%). Overall the probe-based assays detected 16 more positive specimens than the nested gel-based assay. Post-introduction to the routine diagnostic service, a total of 9,846 specimens were processed with multiplex 1 and 2 (7,053 pediatric, 2,793 adult) over the 3-year study period. This clinically validated, probe-based multiplex testing algorithm allows highly sensitive and timely diagnosis of the four most prominent causes of viral gastroenteritis.

Development and validation of a dried blood spot LC-MS/MS assay to quantify ranitidine in paediatric samples.

A novel approach has been developed to determine ranitidine in paediatric samples using dried blood spots (DBS) on Guthrie cards (Whatman 903). A selective and sensitive HPLC-MS/MS assay has been developed and validated using small volumes of blood (30µl). A 6mm disc was punched from each DBS and extracted with methanolic solution of the internal standard (IS) nizatidine. This was further subjected to solid phase extraction (SPE), followed by reversed phase HPLC separation, using a XBridge™ C18 column and mobile phase 10mM ammonium acetate/methanol (98:2 v/v) with a flow rate of 0.3mL/min. This was combined with multiple reaction monitoring (MRM) mass detection using electrospray ionisation (ESI). The calibration curve for ranitidine was found linear over the range 10-500ng/mL (r=0.996). The limit of quantification (LOQ) of the method was validated at 10ng/mL. Accuracy and precision values for within and between days were

Development and independent validation of a prognostic assay for stage ii colon cancer using formalin-fixed paraffin-embedded tissue

Purpose: Current prognostic factors are poor at identifying patients at risk of disease recurrence after surgery for stage II colon cancer. Here we describe a DNA microarray-based prognostic assay using clinically relevant formalin-fixed paraffin-embedded (FFPE) samples. Patients and Methods: A gene signature was developed from a balanced set of 73 patients with recurrent disease (high risk) and 142 patients with no recurrence (low risk) within 5 years of surgery. Results: The 634-probe set signature identified high-risk patients with a hazard ratio (HR) of 2.62 (P <.001) during cross validation of the training set. In an independent validation set of 144 samples, the signature identified high-risk patients with an HR of 2.53 (P <.001) for recurrence and an HR of 2.21 (P = .0084) for cancer-related death. Additionally, the signature was shown to perform independently from known prognostic factors (P <.001). Conclusion: This gene signature represents a novel prognostic biomarker for patients with stage II colon cancer that can be applied to FFPE tumor samples. © 2011 by American Society of Clinical Oncology.

Performance models of storage contention in cloud environments

We propose simple models to predict the performance degradation of disk requests due to storage device contention in consolidated virtualized environments. Model parameters can be deduced from measurements obtained inside Virtual Machines (VMs) from a system where a single VM accesses a remote storage server. The parameterized model can then be used to predict the effect of storage contention when multiple VMs are consolidated on the same server. We first propose a trace-driven approach that evaluates a queueing network with fair share scheduling using simulation. The model parameters consider Virtual Machine Monitor level disk access optimizations and rely on a calibration technique. We further present a measurement-based approach that allows a distinct characterization of read/write performance attributes. In particular, we define simple linear prediction models for I/O request mean response times, throughputs and read/write mixes, as well as a simulation model for predicting response time distributions. We found our models to be effective in predicting such quantities across a range of synthetic and emulated application workloads.