Yersinia pseudotuberculosis and Yersinia pestis show increased outer membrane permeability to hydrophobic agents which correlates with lipopolysaccharide acyl-chain fluidity

The hydrophobic probe N-phenyl-1-naphthylamine accumulated less in non-pathogenic Yersinia spp. and non-pathogenic and pathogenic Yersinia enterocolitica than in Yersinia pseudotuberculosis or Yersinia pestis. This was largely due to differences in the activity of efflux systems, but also to differences in outer membrane permeability because uptake of the probe in KCN/arsenate-poisoned cells was slower in the former group than in Y. pseudotuberculosis and Y. pestis. The probe accumulation rate was higher in Y. pseudotuberculosis and Y. pestis grown at 37 degrees C than at 26 degrees C and was always highest in Y. pestis. These yersiniae had LPSs with shorter polysaccharides than Y. enterocolitica, particularly when grown at 37 degrees C. Gelliquid-crystalline phase transitions (Tc 28-31 degrees C) were observed in LPS aggregates of Y. enterocolitica grown at 26 and 37 degrees C, with no differences between non-pathogenic and pathogenic strains. Y. pseudotuberculosis and Y. pestis LPSs showed no phase transitions and, although the fluidity of LPSs of Y. pseudotuberculosis and Y. enterocolitica grown at 26 degrees C were close below the Tc of the latter, they were always in a more fluid state than Y. enterocolitica LPS. Comparison with previous studies of Salmonella choleraesuis subsp. choleraesuis serotype minnesota rough LPS showed that the increased fluidity and absence of transition of Y. pseudotuberculosis and Y. pestis LPSs cannot be explained by their shorter polysaccharides and suggested differences at the lipid A/core level. It is proposed that differences in LPS-LPS interactions and efflux activity explain the above observations and reflect the adaptation of Yersinia spp. to different habitats.

Endothelium-derived agents in pericyte function/dysfunction

The major components of blood vessels are the vascular endothelium and its supporting smooth muscle. Significant strides have been made in the understanding of the cellular and molecular biology of these two cell types and in particular their interactions have been the subject of much interest and debate over the past two decades. The vascular endothelium is now known to profoundly influence the synthetic and motor functions of the underlying smooth muscle and participate in the pathogenesis of all the major vascular disorders. Similarly, the vascular smooth muscle has important effects on the overlying endothelium, and any disruption in the cellular physiology of either cell type can result in dysfunction with important effects on blood flow and vascular permeability The majority of this accumulated knowledge relates to the vascular cells of the macrocirculation. Pericytes are the supporting cells of the microvasculature and a body of evidence is now available to show that similar regulatory mechanisms and vessel-wall cross-talk exists between these cells and the microvascular endothelium. Nowhere are these interactions more important than in the retinal microcirculation where autoregulation is vital for the maintenance of smooth and uninterrrupted blood flow. This review focuses on the interactions between retinal microvascular endothelial cells and their associated pericytes and examines the role of the endothelial cell and the pericyte in the pathogenesis of disease.

Treatment of a cochlear implant biofilm infection: a potential role for alternative antimicrobial agents

OBJECTIVE:
This study aimed to investigate antimicrobial treatment of an infected cochlear implant, undertaken in an attempt to salvage the infected device.

METHODS:
We used the broth microdilution method to assess the susceptibility of meticillin-sensitive Staphylococcus aureus isolate, cultured from an infected cochlear implant, to common antimicrobial agents as well as to novel agents such as tea tree oil. To better simulate in vivo conditions, where bacteria grow as microcolonies encased in glycocalyx, the bactericidal activity of selected antimicrobial agents against the isolate growing in biofilm were also compared.

RESULTS:
When grown planktonically, the S aureus isolate was susceptible to 17 of the 18 antimicrobials tested. However, when grown in biofilm, it was resistant to all conventional antimicrobials. In contrast, 5 per cent tea tree oil completely eradicated the biofilm following exposure for 1 hour.

CONCLUSION:
Treatment of infected cochlear implants with novel agents such as tea tree oil could significantly improve salvage outcome.

Potential of Microneedles in Enhancing Delivery of Photosensitising Agents for Photodynamic Therapy

Photodynamic therapy can be used in the treatment of pre-malignant and malignant diseases. It offers advantages over other therapies currently used in the treatment of skin lesions including avoidance of damage to surrounding tissue and minimal or no scarring. Unfortunately, systemic delivery of photosensitising agents can result in adverse effects, such as prolonged cutaneous photosensitivity; while topical administration lacks efficacy in the clearance of deeper skin lesions and those with a thick overlying keratotic layer. Therefore, enhancement of conventional photosensitiser delivery is desired. However, the physicochemical properties of photosensitising agents, such as extreme hydrophilicity or lipophilicity and large molecular weights make this challenging. This paper reviews the potential of microneedles as a viable method to overcome these delivery-limiting physicochemical characteristics and discusses the current benefits and limitations of solid, dissolving and hydrogel-forming microneedles. Clinical studies in which microneedles have successfully improved photodynamic therapy are also discussed, along with benefits which microneedles offer, such as precise photosensitiser localisation, painless application and reduction in waiting times between photosensitiser administration and irradiation highlighted.

A simple inhibition coefficient for quantifying potency of biocontrol agents against plant-pathogenic fungi

Microbial interactions depend on a range of biotic and environmental variables, and are both dynamic and unpredictable. For some purposes, and under defined conditions, it is nevertheless imperative to evaluate the inhibitory efficacy of microbes, such as those with potential as biocontrol agents. We selected six, phylogenetically diverse microbes to determine their ability to inhibit the ascomycete Fusarium
coeruleum, a soil-dwelling pathogen of potato tubers that causes the storage disease dry rot. Interaction assays, where colony development was quantified (for both fungal pathogen and potential control agents), were therefore carried out on solid media. The key parameters that contributed to, and were indicative of, inhibitory efficacy were identified as: fungal growth-rates (i) prior to contact with the biocontrol
agent and (ii) if/once contact with the biocontrol agent was established (i.e. in the zone of mixed
culture), and (iii) the ultimate distance traveled by the fungal mycelium. It was clear that there was no correlation between zones of fungal inhibition and the overall reduction in the extent of fungal colony development. An inhibition coefficient was devised which incorporated the potential contributions of distal inhibition of fungal growth-rate; prevention of mycelium development in the vicinity of the biocontrol
agent; and ability to inhibit plant-pathogen growth-rate in the zone of mixed culture (in a ratio of 2:2:1). The values derived were 84.2 for Bacillus subtilis (QST 713), 74.0 for Bacillus sp. (JC12GB42), 30.7 for Pichia anomala (J121), 19.3 for Pantoea agglomerans (JC12GB34), 13.9 for Pantoea sp. (S09:T:12), and
21.9 (indicating a promotion of fungal growth) for bacterial strain (JC12GB54). This inhibition coefficient, with a theoretical maximum of 100, was consistent with the extent of F. coeruleum-colony development (i.e. area, in cm2) and assays of these biocontrol agents carried out previously against Fusarium
spp., and other fungi. These findings are discussed in relation to the dynamics and inherent complexity of natural ecosystems, and the need to adapt models for use under specific sets of conditions.

A critical ethnography of communication processes involving the management of oral chemotherapeutic agents by patients with a primary diagnosis of colorectal cancer: study protocol

Aim
To describe the protocol used to examine the processes of communication between health professionals, patients and informal carers during the management of oral chemotherapeutic medicines to identify factors that promote or inhibit medicine concordance.

Background
Ideally communication practices about oral medicines should incorporate shared decision-making, two-way dialogue and an equality of role between practitioner and patient. While there is evidence that healthcare professionals are adopting these concordant elements in general practice there are still some patients who have a passive role during consultations. Considering oral chemotherapeutic medications, there is a paucity of research about communication practices which is surprising given the high risk of toxicity associated with chemotherapy.

Design
A critical ethnographic design will be used, incorporating non-participant observations, individual semi-structured and focus-group interviews as several collecting methods.

Methods
Observations will be carried out on the interactions between healthcare professionals (physicians, nurses and pharmacists) and patients in the outpatient departments where prescriptions are explained and supplied and on follow-up consultations where treatment regimens are monitored. Interviews will be conducted with patients and their informal carers. Focus-groups will be carried out with healthcare professionals at the conclusion of the study. These several will be analysed using thematic analysis. This research is funded by the Department for Employment and Learning in Northern Ireland (Awarded February 2012).

Discussion
Dissemination of these findings will contribute to the understanding of issues involved when communicating with people about oral chemotherapy. It is anticipated that findings will inform education, practice and policy.

Plan Selection for Probabilistic BDI Agents

When an agent wants to fulfill its desires about the world, the agent usually has multiple plans to choose from and these plans have different pre-conditions and additional effects in addition to achieving its goals. Therefore, for further reasoning and interaction with the world, a plan selection strategy (usually based on plan cost estimation) is mandatory for an autonomous agent. This demand becomes even more critical when uncertainty on the observation of the world is taken into account, since in this case, we consider not only the costs of different plans, but also their chances of success estimated according to the agent's beliefs. In addition, when multiple goals are considered together, different plans achieving the goals can be conflicting on their preconditions (contexts) or the required resources. Hence a plan selection strategy should be able to choose a subset of plans that fulfills the maximum number of goals while maintaining context consistency and resource-tolerance among the chosen plans. To address the above two issues, in this paper we first propose several principles that a plan selection strategy should satisfy, and then we present selection strategies that stem from the principles, depending on whether a plan cost is taken into account. In addition, we also show that our selection strategy can partially recover intention revision.

Criminal Justice Reforms in Northern Ireland: The Agents of Change

This chapter examines who and what brought about the transformation in the criminal justice system of Northern Ireland between 1998 and 2015, seeking to pinpoint the critical moments which stimulated the reforms, how they were delivered, and through what processes they are now being maintained. It seeks to identify the key agents of change and considers whether it is possible to generalise from Northern Ireland’s experience so that other conflicted societies might benefit from the lessons learned.

Transforming Growth Factor-beta superfamily:evaluation as breast cancer biomarkers and preventive agents

The Transforming Growth Factor-beta (TGFbeta) superfamily of cytokines is comprised of a number of structurally-related, secreted polypeptides that regulate a multitude of cellular processes including proliferation, differentiation and neoplastic transformation. These growth regulatory molecules induce ligand-mediated hetero-oligomerization of distinct type II and type I serine/threonine kinase receptors that transmit signals predominantly through receptor-activated Smad proteins but also induce Smad-independent pathways. Ligands, receptors and intracellular mediators of signaling initiated by members of the TGFbeta family are expressed in the mammary gland and disruption of these pathways may contribute to the development and progression of human breast cancer. Since many facets of TGFbeta and breast cancer have been recently reviewed in several articles, except for discussion of recent developments on some aspects of TGFbeta, the major focus of this review will be on the role of activins, inhibins, BMPs, nodal and MIS-signaling in breast cancer with emphasis on their utility as potential diagnostic, prognostic and therapeutic targets.