Protection of pigs against challenge with virulent <i>Streptococcus suis</i> serotype 2 strains by a muramidase-released protein and extracellular factor vaccine

The efficacy of a muramidase-released protein (MRP) and extracellular factor (EF) vaccine in preventing infection and disease in pigs challenged either with a homologous or a heterologous Streptococcus suis serotype 2 strain (MRP EF ) was compared with the efficacy of a vaccine containing formalin-killed bacterin of S suis serotype 2 (MRP EF ). The enhancement of the immune response by different adjuvants (a water-in-oil emulsion [wo] and an aluminium hydroxide-based adjuvant [AH]) and their side effects were also studied. The MRP and EF were purified by affinity chromatography. Pigs were vaccinated twice at three weeks and six weeks of age and challenged intravenously with virulent S suis serotype 2 strains (MRP EF ) at eight weeks of age. At challenge, the pigs vaccinated with MRP EF/WO had high anti-MRP and anti-EF titres and were protected as effectively as pigs vaccinated with wo-formulated vaccines with bacterin. Eight of the nine pigs survived the challenge and almost no clinical signs of disease were observed. The titres obtained with the MRP EF/AH vaccine were low and only two of the five pigs were protected. Pigs vaccinated with either MRP or EF were less well protected; three of the four pigs died after challenge but the clinical signs of disease were significantly less severe than those observed in the placebo-vaccinated pigs. The protective capacity of the bacterin/AH vaccine was very low, and the mortality among these pigs was as high as in the placebo-vaccinated pigs (80 per cent). Postmortem histological examination revealed meningitis, polyserositis and arthritis in the clinically affected pigs. The results demonstrate that a subunit vaccine containing both MRP and EF, formulated with the wo adjuvant, protected pigs against challenge with virulent S suis type 2 strains

ApuA, a multifunctional x-glucan-degrading enzyme of Streptococcus suis, mediates adhesion to porcine epithelium and mucus

We have identified apuA in Streptococcus suis, which encodes a bifunctional amylopullulanase with conserved -amylase and pullulanase substrate-binding domains and catalytic motifs. ApuA exhibited properties typical of a Gram-positive surface protein, with a putative signal sequence and LPKTGE cell-wall-anchoring motif. A recombinant protein containing the predicted N-terminal -amylase domain of ApuA was shown to have -(1,4) glycosidic activity. Additionally, an apuA mutant of S. suis lacked the pullulanase -(1,6) glycosidic activity detected in a cell-surface protein extract of wild-type S. suis. ApuA was required for normal growth in complex medium containing pullulan as the major carbon source, suggesting that this enzyme plays a role in nutrient acquisition in vivo via the degradation of glycogen and food-derived starch in the nasopharyngeal and oral cavities. ApuA was shown to promote adhesion to porcine epithelium and mucus in vitro, highlighting a link between carbohydrate utilization and the ability of S. suis to colonize and infect the host

Learners, Learning Styles and Learning Media

In: A.J. Kallenberg and M.J.J.M. van de Ven (Eds), 2002, The New Educational Benefits of ICT in Higher Education: Proceedings. Rotterdam: Erasmus Plus BV, OECR ISBN 90-9016127-9The paper is an account of an ongoing research project studying the links between learning style and learning media. The particular focus of the paper is on online learning. For centuries the lecture was the standard method of teaching in higher education, but the widespread introduction of ICT into Higher Education has led to dramatically increased educational benefits for learners. These benefits can be summarized as increased access to learning material and increased learner control of that material, and this, in turn, makes individual differences between learners an important factor in the learning process. A series of studies are reported using second year and third year psychology undergraduates, whose detailed examination marks were obtained in order to establish whether examination performance was a function of teaching method. Results were inconsistent, but there was evidence to suggest that lectures were the least effective teaching medium. When learning styles were measured using the Cognitive Style Index (Allinson and Hayes, 1991), some effects of learning style effects of learning style were apparent and a comparison between learning style and marks from lecture-based and online-based examination questions showed significant interactions between learning style and teaching medium – with web-based learning favouring the analytical learning style and summarized material favouring the intuitive learning style

ClgR regulation of chaperone and protease systems is essential for Mycobacterium tuberculosis parasitism of the macrophage

Chaperone and protease systems play essential roles in cellular homeostasis and have vital functions in controlling the abundance of specific cellular proteins involved in processes such as transcription, replication, metabolism and virulence. Bacteria have evolved accurate regulatory systems to control the expression and function of chaperones and potentially destructive proteases. Here, we have used a combination of transcriptomics, proteomics and targeted mutagenesis to reveal that the clp gene regulator (ClgR) of Mycobacterium tuberculosis activates the transcription of at least ten genes, including four that encode protease systems (ClpP1/C, ClpP2/C, PtrB and HtrA-like protease Rv1043c) and three that encode chaperones (Acr2, ClpB and the chaperonin Rv3269). Thus, M. tuberculosis ClgR controls a larger network of protein homeostatic and regulatory systems than ClgR in any other bacterium studied to date. We demonstrate that ClgR-regulated transcriptional activation of these systems is essential for M. tuberculosis to replicate in macrophages. Furthermore, we observe that this defect is manifest early in infection, as M. tuberculosis lacking ClgR is deficient in the ability to control phagosome pH 1 h post-phagocytosis

Sexual healthcare professionals’ views on HPV vaccination for men in the UK

Background: Human Papillomavirus (HPV) vaccination for men could prevent anal cancers amongst men who have sex with men (MSM). Methods: An e-survey of attitudes towards vaccination for men in the UK was conducted in July–August 2014. Results: Among 325 sexual health professionals, 14% were already vaccinating men against HPV, 83% recommended genderneutral HPV vaccination and 65% recommended targeting MSM. Over 50% reported having poor knowledge about the use of HPV vaccine for MSM and the skills to identify MSM likely to benefit from HPV vaccination. Conclusions: Clear advice and guidelines on HPV vaccine use for men at sexual health clinics are required to ensure equitable opportunities for vaccination

Effects of Confinement Feeding Systems on Beef Cattle Production

Several factors have stimulated interest in housing systems for feedlot cattle. Some of these factors are (1) the desire to eliminate problems associated with the use of bedding, (2) the desire to decrease the labor required for feeding, bedding and manure handling, (3) the need to develop effective pollution control measures and (4) the desire to know the effects that housing systems may have on the performance and carcass characteristics of feedlot cattle. The objectives of the trials reported herein were (1) to study the influence of housing systems on the performance of finishing steer calves and (2) to study the effect of animal density on feedlot performance. The housing systems studied are described below

ArgR is an essential local transcriptional regulator of the arcABC-operon in Streptococcus suis and crucial for biological fitness in acidic environment

Streptococcus suis is one of the most important pathogens in pigs and can also cause severe infections in humans. Despite its clinical relevance very little is known about the factors contributing to its virulence. Recently, we identified a new putative virulence factor in Streptococcus suis, the arginine deiminase system (ADS), an arginine catabolic enzyme system encoded by the arcABC-operon, which enables Streptococcus suis to survive in acidic environment. In this study, we focused on ArgR, an ADS associated regulator belonging to the ArgR/AhrC arginine repressor family. Using an argR knock-out strain we could show that ArgR is essential for arcABC-operon expression and necessary for the biological fitness of Streptococcus suis. By cDNA expression microarray analyses and quantitative real time RT-PCR we found that the arcABC-operon is the only gene cluster regulated by ArgR, which is in contrast to many other bacteria. Reporter gene analysis with gfp under the control of the arcABC promoter demonstrated that ArgR is able to activate the arcABC promoter. Electrophoretic mobility shift assays with fragments of the arcABC promoter and recombinant ArgR, and chromatin immunoprecipitation with antibodies directed against ArgR revealed that ArgR interacts with the arcABC promoter in vitro and in vivo by binding to a region from -147 to 72 bp upstream of the transcriptional start point. Overall our results show that in Streptococcus suis ArgR is an essential, system specific transcriptional regulator of the ADS directly interacting with the arcABC promoter in vivo

Companion planting to attract pollinators increases the yield and quality of strawberry fruit in gardens and allotments

1. Global pollinator declines have led to concern that crop yields might fall as a result of a pollination deficit. Companion planting is a traditional practice thought to increase yield of insect pollinated crops by planting a co-flowering species next to the crop. 2. Using a combination of conventional researcher-led experiments and observational citizen scientist data, we tested the effectiveness of bee-friendly borage (Borago officinalis) as a companion plant to strawberry (Fragaria x ananassa). Insect visitors to the ‘Test’ (strawberry + borage) versus ‘Control’ (strawberry only) plants were observed, and strawberry fruit collected. Strawberries collected during the researcher-led experiment were also subject to fruit measurements and assessments of market quality. 3. Companion plants were found to significantly increase both yield and market quality of strawberries, suggesting an increase in insect pollination per plant. Test strawberries companion planted with borage produced an average of 35% more fruits, and 32% increased yield by weight. Test strawberry plants produced significantly more fruit of higher aesthetic quality when assessed by Marketing Standards for Strawberries. 4. Although there was no significant difference in the overall insect visits, when broken down by broad insect group there were significantly more flies visiting the test strawberries than controls. 5. These results could have implications for both gardeners and commercial growers. As consumers prefer a cosmetically perfect fruit, the production of fruit with increased aesthetics aids food waste reduction

A method for reconstruction of residual stress fields from measurements made in an incompatible region

AbstractA method is introduced by which the complete state of residual stress in an elastic body may be inferred from a limited set of experimental measurements. Two techniques for carrying out this reconstruction using finite element analysis are compared and it is shown that for exact reconstruction of the stress field via this method, the stress field must be measured over all eigenstrain-containing regions of the object. The effects of error and incompleteness in the measured part of the stress field on the subsequent analysis are investigated in a series of numerical experiments using synthetic measurement data based on the NeT TG1 round-robin weld specimen. It is hence shown that accurate residual stress field reconstruction is possible using measurement data of a quality achievable using current experimental techniques

Rooting out ultraweak photon emission a-mung bean sprouts

It is well known that life has evolved to use and generate light, for instance, photosynthesis, vision and bioluminescence. What is less well known is that during normal metabolism, it can generate 1–100 photons s−1 cm–2 known as ultra-weak photon emission (UPE), biophoton emission or biological autoluminescence. The highest generation of these metabolic photons seem to occur during oxidative stress due to the generation and decay of reactive oxygen species (ROS), and their interaction with other components of the cell. To study this further, we have configured a sensitive detection system to study photon emission in germinating mung beans. Here we investigated growing mung beans over 7 days at a constant temperature of 21 ± 1 °C in a light tight box, using dual top and bottom opposing photomultiplier tubes. Over this time period we showed that in total, mung beans grown from seeds generated an average of 5 ± 1 counts s−1 above background. As the new bean stems grew, they showed a gradual linear increase in emission of up to 30 ± 1 counts s−1, in agreement with previous literature. In addition to this “steady-state” emission we also observe delayed luminescence and drought-stress response emission previously observed in other species. Finally, we also observe episodic increased emission events of between 2 and 15 counts s−1 for durations of around 3 h detected underneath the sample, and assign these to the growing of secondary roots. We then induce secondary root formation using aqueous solutions of growth hormones hydrogen peroxide (H2O2, 167 µM) or 3-indole acetic acid (IAA, 0.5 µM) for watering. Both hormones show prolonged increase in emission above steady-state, over days 3–5 with at least 3 times the number of secondary roots formed compared with water alone. We also observed a significant peak increase in photon emission (474 and 1738 cps vs. 28 and 55 cps for water alone) for the H2O2 which we attribute to direct ROS reaction emission as confirmed by measurement on dead plants. Altogether we have expanded upon and demonstrated an instrument and biological system for reliably producing and measuring intrinsic metabolic photons, first observed 100 years ago by Alexander Gurwitsch