Rational engineering of recombinant picornavirus capsids to produce safe, protective vaccine antigen

Foot-and-mouth disease remains a major plague of livestock and outbreaks are often economically catastrophic. Current inactivated virus vaccines require expensive high containment facilities for their production and maintenance of a cold-chain for their activity. We have addressed both of these major drawbacks. Firstly we have developed methods to efficiently express recombinant empty capsids. Expression constructs aimed at lowering the levels and activity of the viral protease required for the cleavage of the capsid protein precursor were used; this enabled the synthesis of empty A-serotype capsids in eukaryotic cells at levels potentially attractive to industry using both vaccinia virus and baculovirus driven expression. Secondly we have enhanced capsid stability by incorporating a rationally designed mutation, and shown by X-ray crystallography that stabilised and wild-type empty capsids have essentially the same structure as intact virus. Cattle vaccinated with recombinant capsids showed sustained virus neutralisation titres and protection from challenge 34 weeks after immunization. This approach to vaccine antigen production has several potential advantages over current technologies by reducing production costs, eliminating the risk of infectivity and enhancing the temperature stability of the product. Similar strategies that will optimize host cell viability during expression of a foreign toxic gene and/or improve capsid stability could allow the production of safe vaccines for other pathogenic picornaviruses of humans and animals

Product and process innovation in manufacturing firms: a 30-year bibliometric analysis

Built upon a thirty-year dataset collected from the Web of Science database, the present research aims to offer a comprehensive overview of papers, authors, streams of research, and the most influential journals that discuss product and process innovation in the manufacturing environment. The dataset is composed of 418 papers from more than 150 journals from the period between 1985 and 2015. Homogeneity analysis by means of alternating least squares (HOMALS) and Social Network Analysis (SNA) are used to accomplish the objectives listed above through the keywords given by authors. Initially, the paper highlights and discusses the similarity between the topics debated by the main journals in this field. Subsequently, a wide-range map of topics is presented highlighting five main areas of interests; namely, performance, patent, small firm, product development, and organization. A SNA is also performed in order to validate the results that emerged from HOMALS. Finally, several insights about future research avenues in the manufacturing field are provided

Faith and Fair Trade: The Moderating Role of Contextual Religious Salience

Normative and historical arguments support the idea that religion potentially shapes decisions to support fair trade products. That said, the question of how religion influences organizational decision-makers to purchase fair trade products in a business-to-business context has remained largely unaddressed. This research examines the interactive effect of individual religious commitment and contextual religious salience on an individual's willingness to pay a price premium for a fair trade product, when buying on behalf of an organization. Findings from two experimental studies (involving 75 and 87 working individuals, respectively) reveal that the effect of a decision-maker's religious commitment on his or her willingness to pay a price premium, for the purchase of a fair trade product on behalf of an organization, is moderated by the contextual salience of religion. Specifically, when religion is highly salient in the organizational context, religious commitment is positively related to the decision-maker's willingness to pay a premium for the fair trade product; when contextual religious salience is low, religious commitment and willingness to pay a premium are unrelated. Implications for theory and practice are presented. © 2013 Springer Science+Business Media Dordrecht

The Application of Flow Cytometry for Estimating Genome Size, Ploidy Level Endopolyploidy, and Reproductive Modes in Plants

Over the years, the amount of DNA in a nucleus (genome size) has been estimated using a variety of methods, but increasingly, flow cytometry (FCM) has become the method of choice. The popularity of this technique lies in the ease of sample preparation and in the large number of particles (i.e., nuclei) that can be analyzed in a very short period of time. This chapter presents a step-by-step guide to estimating the nuclear DNA content of plant nuclei using FCM. Attempting to serve as a tool for daily laboratory practice, we list, in detail, the equipment required, specific reagents and buffers needed, as well as the most frequently used protocols to carry out nuclei isolation. In addition, solutions to the most common problems that users may encounter when working with plant material and troubleshooting advice are provided. Finally, information about the correct terminology to use and the importance of obtaining chromosome counts to avoid cytological misinterpretations of the FCM data are discussed

Endocrine disruption in a terrestrial isopod under exposure to bisphenol A and vinclozolin

Background, aim, and scope In the past decade there has been an increasing awareness about the possible consequences of human and wildlife exposure to endocrine disrupting compounds (EDCs). Bisphenol A (BPA) and vinclozolin (Vz) are EDCs which impacts on vertebrates have been largely investigated. Nevertheless, research on invertebrate effects, especially on soil organisms, are still largely under-represented. This work aims to extend the limited ecotoxicological datasets available and to provide tools to assess the effects of EDCs on the terrestrial species, using Porcellio scaber (Crustacea: Isopoda) as a model organism. Materials and methods Male adult isopods were exposed for 10 weeks to BPA and Ronilan(R) [containing 50% Vz as active ingredient (a.i.)] at concentrations of 10, 30, 100, 300, and 1,000 mg a.i./kg of soil and compared to non-exposed isopods. We studied the effects of these EDCs on molting and total ecdysteroid (20E) concentration. Young, sexually undifferentiated isopods were also exposed to these compounds (Vz, 5, 10, 25, 50, and 100 mg a.i./kg of soil; and BPA, 10, 25, 50, 150, and 300 mg/kg of soil) for 16 weeks and effects on sex ratio were assessed. Results Exposure to both chemicals resulted in toxic effects on isopods. Time to first molt was delayed with increasing concentrations of Vz. After 10 weeks exposure to 1,000 mg a.i. Vz/kg soil, 100% mortality occurred due to incomplete ecdysis. BPA induced an opposite effect as animals started to molt sooner. Vz significantly increased the 20E titres after 7 and 14 days (LOEC 300 mg a.i. Vz/kg soil) and after 28 days of exposure the LOEC value was 100 mg a.i. Vz/kg soil. BPA also induced a 20E concentration increase after 28 days of exposure at 10, 300, and 1,000 mg/kg soil. In juveniles, we observed a low-dose alteration of sex ratio in BPA-exposed organisms with a skewed ratio of one male per two females, which is in contrast to an almost equal gender distribution in the control. Vz induced no alterations in the sex ratio of isopods. Discussion Results show that chronic Vz exposure induces a high mortality in P. scaber. This is not consistent with other studies describing non-toxicity of fungicides to arthropods. Therefore, it is desirable that toxicity assessment of fungicides is performed via chronic exposure and full life cycle tests. Previously reported low-dose responses to BPA in vertebrates are consistent with results of the present study regarding a sex-ratio shift induced by low BPA concentrations. Enhanced mortality turned out to be the effect of incomplete ecdysis related to increased ecdysteroids titres. Therefore, 'hyperecdysonism' might be a promising end-point to detect and assess endocrine disruption (ED) in arthropods inhabiting the terrestrial environment. Conclusions This work reveals that both Vz and BPA disrupt the endocrine function of these important representatives of soil edaphic invertebrates. For the first time, the existence of 'low-dose effects' affecting soil invertebrates is reported. Therefore, isopods are suitable organisms for ED assessment and endpoints such as molting, sex ratio, or 20E concentration are valuable tools for ecotoxicological studies on hormonally active substances. Recommendations and perspectives Although the effects observed in the present study have not been induced at environmentally relevant concentrations, synergistic interactions of EDC mixtures present in the environment may well have an impact on arthropods at lower substance concentrations. Additionally, the low-dose sex-ratio change demonstrated here confirms the importance of the choice for a large concentration range. The assessment of potential EDCs should consider chronic exposures and life cycle studies. Although the modes of action of EDCs in many arthropods are fragmentary, parameters like molting impairment, incomplete ecdysis, and the determination of hormone titres seem to be suitable biomarkers that should be included as soon as possible in regular surveys for the detection of hormonally active substances