Assessing the use of minimally invasive self-sampling at home for long-term monitoring of the microbiota within UK families.

Monitoring the presence of commensal and pathogenic respiratory microorganisms is of critical global importance. However, community-based surveillance is difficult because nasopharyngeal swabs are uncomfortable and painful for a wide age range of participants. We designed a methodology for minimally invasive self-sampling at home and assessed its use for longitudinal monitoring of the oral, nasal and hand microbiota of adults and children within families. Healthy families with two adults and up to three children, living in and near Liverpool, United Kingdom, self-collected saliva, nasal lining fluid using synthetic absorptive matrices and hand swabs at home every two weeks for six months. Questionnaires were used to collect demographic and epidemiological data and assess feasibility and acceptability. Participants were invited to take part in an exit interview. Thirty-three families completed the study. Sampling using our approach was acceptable to 25/33 (76%) families, as sampling was fast (76%), easy (76%) and painless (60%). Saliva and hand sampling was acceptable to all participants of any age, whereas nasal sampling was accepted mostly by adults and children older than 5 years. Multi-niche self-sampling at home can be used by adults and children for longitudinal surveillance of respiratory microorganisms, providing key data for design of future studies.

Amplification of acidic protease virulence gene (aprV2) in samples from footrot lesions did not help in diagnosis of clinical virulent footrot in affected sheep flocks in New South Wales.

OBJECTIVE: Ovine footrot is a contagious bacterial disease that reduces meat and wool production and can trigger on-farm quarantine in New South Wales. Field diagnosis is based on the prevalence and severity of foot lesions, environmental conditions and flock history. The study evaluated whether a PCR assay or gelatin gel test for virulence in Dichelobacter nodosus isolated from hoof material could aid in the clinical diagnosis of virulent footrot. METHODS: A quantitative polymerase chain reaction (qPCR) used for diagnosis of virulent footrot in some Australian states was evaluated on 218 hoof swabs taken from 44 sheep flocks from 36 NSW properties, quantifying both the aprV2 positive and aprB2 positive acidic protease genotypes of D. nodosus. DESIGN: The same flocks/swabs were used to evaluate test agreement between the aprV2/B2 qPCR and the gelatin gel test, and a multiple logistic regression was used to identify factors critical for field diagnosis of virulent footrot. RESULTS: Only fair to moderate agreement (kappa test) and significant disagreement (McNemar's) was shown between the gelatin gel test and the ratio of aprV2 positive to total D. nodosus. The proportion of aprV2 positive D. nodosus was not significantly different between foot lesions scores of increasing severity. Field diagnosis of virulent footrot was best explained by the prevalence of score 4 and 5 lesions, wet and warm environmental conditions, and recent footrot diagnosis. CONCLUSION: Although the apr2 gene could differentiate between benign and virulent strains of D. nodosus, the apr2 qPCR was of minimal use for field diagnosis of virulent footrot, where disease expression relies on host genetics, immunity and environmental conditions.

Protective effect of PCV vaccine against experimental pneumococcal challenge in adults is primarily mediated by controlling colonisation density.

Widespread use of Pneumococcal Conjugate Vaccines (PCV) has reduced vaccine-type nasopharyngeal colonisation and invasive pneumococcal disease. In a double-blind, randomised controlled trial using the Experimental Human Pneumococcal Challenge (EHPC) model, PCV-13 (Prevenar-13) conferred 78% protection against colonisation acquisition and reduced bacterial intensity (AUC) as measured by classical culture. We used a multiplex qPCR assay targeting lytA and pneumococcal serotype 6A/B cpsA genes to re-assess the colonisation status of the same volunteers. Increase in detection of low-density colonisation resulted in reduced PCV efficacy against colonisation acquisition (29%), compared to classical culture (83%). For experimentally colonised volunteers, PCV had a pronounced effect on decreasing colonisation density. These results obtained in adults suggest that the success of PCV vaccination could primarily be mediated by the control of colonisation density. Studies assessing the impact of pneumococcal vaccines should allow for density measurements in their design.

Pulmonary infections in the returned traveller.

Pulmonary infections in the returned traveller are a common presentation. A wide variety of infections may present with pulmonary symptoms. It is important for clinicians to differentiate the cause of these symptoms. The risk of contracting certain travel-related pulmonary diseases depends on travel destination, length of stay, activities undertaken and co-morbidities. Some pathogens are found worldwide, whilst others are related to specific locations. This review article will discuss the approach to diagnosing and treating pulmonary infections in the returned traveller.

Giant desmoid tumour of the thorax following latissimus dorsi and implant breast reconstruction: case report and review of the literature.

The case of a giant thoracic desmoid tumour in a 44-year-old woman, who presented two years following a breast reconstruction with a latissimus dorsi (LD) flap and implant, is reported. Clinical findings included a rapidly growing, painless mass. Computed tomography (CT) suggested skin and intercostal soft tissue invasion. The tumour was resected en bloc with the LD muscle, implant capsule and underlying rib segments. The resultant thoracic and abdominal wall defects were reconstructed with Dualmesh® and polypropylene meshes respectively. There was no evidence of recurrence at thirty-six months follow-up.

Convection enhanced delivery of panobinostat (LBH589)-loaded pluronic nano-micelles prolongs survival in the F98 rat glioma model.

BACKGROUND: The pan-histone deacetylase inhibitor panobinostat is a potential therapy for malignant glioma, but it is water insoluble and does not cross the blood-brain barrier when administered systemically. In this article, we describe the in vitro and in vivo efficacy of a novel water-soluble nano-micellar formulation of panobinostat designed for administration by convection enhanced delivery (CED). MATERIALS AND METHODS: The in vitro efficacy of panobinostat-loaded nano-micelles against rat F98, human U87-MG and M059K glioma cells and against patient-derived glioma stem cells was measured using a cell viability assay. Nano-micelle distribution in rat brain was analyzed following acute CED using rhodamine-labeled nano-micelles, and toxicity was assayed using immunofluorescent microscopy and synaptophysin enzyme-linked immunosorbent assay. We compared the survival of the bioluminescent syngenic F98/Fischer344 rat glioblastoma model treated by acute CED of panobinostat-loaded nano-micelles with that of untreated and vehicle-only-treated controls. RESULTS: Nano-micellar panobinostat is cytotoxic to rat and human glioma cells in vitro in a dose-dependent manner following short-time exposure to drug. Fluorescent rhodamine-labelled nano-micelles distribute with a volume of infusion/volume of distribution (Vi/Vd) ratio of four and five respectively after administration by CED. Administration was not associated with any toxicity when compared to controls. CED of panobinostat-loaded nano-micelles was associated with significantly improved survival when compared to controls (n=8 per group; log-rank test, P<0.001). One hundred percent of treated animals survived the 60-day experimental period and had tumour response on post-mortem histological examination. CONCLUSION: CED of nano-micellar panobinostat represents a potential novel therapeutic option for malignant glioma and warrants translation into the clinic.

Agglutination by anti-capsular polysaccharide antibody is associated with protection against experimental human pneumococcal carriage.

The ability of pneumococcal conjugate vaccine (PCV) to decrease transmission by blocking the acquisition of colonization has been attributed to herd immunity. We describe the role of mucosal immunoglobulin G (IgG) to capsular polysaccharide (CPS) in mediating protection from carriage, translating our findings from a murine model to humans. We used a flow cytometric assay to quantify antibody-mediated agglutination demonstrating that hyperimmune sera generated against an unencapsulated mutant was poorly agglutinating. Passive immunization with this antiserum was ineffective to block acquisition of colonization compared to agglutinating antisera raised against the encapsulated parent strain. In the human challenge model, samples were collected from PCV and control-vaccinated adults. In PCV-vaccinated subjects, IgG levels to CPS were increased in serum and nasal wash (NW). IgG to the inoculated strain CPS dropped in NW samples after inoculation suggesting its sequestration by colonizing pneumococci. In post-vaccination NW samples pneumococci were heavily agglutinated compared with pre-vaccination samples in subjects protected against carriage. Our results indicate that pneumococcal agglutination mediated by CPS-specific antibodies is a key mechanism of protection against acquisition of carriage. Capsule may be the only vaccine target that can elicit strong agglutinating antibody responses, leading to protection against carriage acquisition and generation of herd immunity.

Amphiphilic block copolymers as flexible membrane materials generating structural and functional mimics of green bacterial antenna complexes.

We describe the ability of a short-chain amphiphilic block copolymer to self-assemble to form an artificial supramolecular light-harvesting system. Specifically, we demonstrate that the 2.5 kDa, poly(ethylene oxide)-block-poly(butadiene) (PEO-b-PBD), exhibits sufficient morphological flexibility as a membrane material and enables generation of mimics of three-dimensional chlorosomes as well as supported membrane bilayers containing energy acceptors. This overall architecture replicates green bacterial light-harvesting function whereby these assemblies exhibit long-range order and three-dimensional morphology similar to native chlorosomes and are capable of energy transfer internally and to external acceptors, located in a supporting biomimetic polymer membrane. Unlike native green bacterial systems that use multiple lipids as a matrix to generate the appropriate environment for chlorosome assembly and function, the described system matrix is comprised entirely of a single polymer amphiphile. This work demonstrates the potential of short-chain amphiphilic block copolymers in generating self-assembled, bio-mimetic membrane architectures, and in doing so, generates scalable, spatial-energetic landscapes for photonic applications. Finally, the results presented provide evidence of minimal requirements to induce chlorosome-like organization and function.

Modulation of nasopharyngeal innate defenses by viral coinfection predisposes individuals to experimental pneumococcal carriage.

Increased nasopharyngeal colonization density has been associated with pneumonia. We used experimental human pneumococcal carriage to investigate whether upper respiratory tract viral infection predisposes individuals to carriage. A total of 101 healthy subjects were screened for respiratory virus before pneumococcal intranasal challenge. Virus was associated with increased odds of colonization (75% virus positive became colonized vs. 46% virus-negative subjects; P=0.02). Nasal Factor H (FH) levels were increased in virus-positive subjects and were associated with increased colonization density. Using an in vitro epithelial model we explored the impact of increased mucosal FH in the context of coinfection. Epithelial inflammation and FH binding resulted in increased pneumococcal adherence to the epithelium. Binding was partially blocked by antibodies targeting the FH-binding protein Pneumococcal surface protein C (PspC). PspC epitope mapping revealed individuals lacked antibodies against the FH binding region. We propose that FH binding to PspC in vivo masks this binding site, enabling FH to facilitate pneumococcal/epithelial attachment during viral infection despite the presence of anti-PspC antibodies. We propose that a PspC-based vaccine lacking binding to FH could reduce pneumococcal colonization, and may have enhanced protection in those with underlying viral infection.

Effect of the route of administration on the mucosal and systemic immune responses to Lawsonia intracellularis vaccine in pigs.

In an on-farm study, 40 weaned piglets aged 3 weeks were vaccinated with Lawsonia intracellularis vaccine orally, IM or IP while a fourth group remained unvaccinated. All vaccinated animals showed increased serum levels of L. intracellularis-specific IgG antibodies, but significantly elevated concentrations of specific IgG, IgA and cytokines were generated in ileal mucosal secretions from the orally and IP vaccinated pigs when examined at 17 days after vaccination.

IgE+ B cells are scarce, but allergen-specific B cells with a memory phenotype circulate in patients with allergic rhinitis.

BACKGROUND: Despite the critical role of immunoglobulin E (IgE) in allergy, circulating IgE+ B cells are scarce. Here, we describe in patients with allergic rhinitis B cells with a memory phenotype responding to a prototypic aeroallergen. METHODS: Fifteen allergic rhinitis patients with grass pollen allergy and 13 control subjects were examined. Blood mononuclear cells stained with carboxyfluorescein diacetate succinimidyl ester (CFSE) were cultured with Bahia grass pollen. Proliferation and phenotype were assessed by multicolour flow cytometry. RESULTS: In blood of allergic rhinitis patients with high serum IgE to grass pollen, most IgE(hi) cells were CD123+ HLA-DR(-) basophils, with IgE for the major pollen allergen (Pas n 1). Both B and T cells from pollen-allergic donors showed higher proliferation to grass pollen than nonallergic donors (P = 0.002, and 0.010, respectively), whereas responses to vaccine antigens and mitogen did not differ between groups. Allergen-driven B cells that divided rapidly (CD19(mid) CD3(-) CFSE(lo) ) showed higher CD27 (P = 0.008) and lower CD19 (P = 0.004) and CD20 (P = 0.004) expression than B cells that were slow to respond to allergen (CD19(hi) CD3(-) CFSE(mid) ). Moreover, rapidly dividing allergen-driven B cells (CD19(mid) CFSE(lo) CD27(hi) ) showed higher expression of the plasmablast marker CD38 compared with B cells (CD19(hi) CFSE(mid) CD27(lo) ) that were slow to divide. CONCLUSION: Patients with pollen allergy but not control donors have a population of circulating allergen-specific B cells with the phenotype and functional properties of adaptive memory B-cell responses. These cells could provide precursors for allergen-specific IgE production upon allergen re-exposure.

Comparison between magnetic force microscopy and electron back-scatter diffraction for ferrite quantification in type 321 stainless steel.

Several analytical techniques that are currently available can be used to determine the spatial distribution and amount of austenite, ferrite and precipitate phases in steels. The application of magnetic force microscopy, in particular, to study the local microstructure of stainless steels is beneficial due to the selectivity of this technique for detection of ferromagnetic phases. In the comparison of Magnetic Force Microscopy and Electron Back-Scatter Diffraction for the morphological mapping and quantification of ferrite, the degree of sub-surface measurement has been found to be critical. Through the use of surface shielding, it has been possible to show that Magnetic Force Microscopy has a measurement depth of 105-140 nm. A comparison of the two techniques together with the depth of measurement capabilities are discussed.

Organizational sensemaking about risk controls: the case of offshore hydrocarbons production.

In the same way that individuals' risk perceptions can influence how they behave toward risks, how organizational members make sense of risk controls is an important influence on how they apply and maintain such controls. In this article, we describe an analysis of sensemaking about the control of risk in offshore hydrocarbons production, an industry that continues to produce disasters of societal significance. A field study of 80 interviews was conducted in five offshore oil and gas companies and the agency that regulates them. The interviews were analyzed using qualitative template analysis. This provided a categorization of the many ways of acting through which informants made sense of the risk control task, and indicated that the organizations placed substantially different emphases on different ways of acting. Nevertheless, this sensemaking fell into two broad classes: that which tended to limit or be pessimistic about organizational controls, and that which tended to extend or be optimistic about organizational controls. All the participating organizations collectively placed a balanced emphasis on these two classes. We argue that this balanced sensemaking is an adaptation rather than a deliberate choice, but that it is an important element of controlling risk in its own right.

Suitability of invertebrate and vertebrate cells in a portable impedance-based toxicity sensor: temperature mediated impacts on long-term survival.

Using ECIS (electric cell-substrate impedance sensing) to monitor the impedance of vertebrate cell monolayers provides a sensitive measure of toxicity for a wide range of chemical toxicants. One major limitation to using a cell-based sensor for chemical toxicant detection in the field is the difficulty in maintaining cell viability over extended periods of time prior to use. This research was performed to identify cell lines suitable for ECIS-based toxicity sensing under field conditions. A variety of invertebrate and vertebrate cell lines were screened for their abilities to be stored for extended periods of time on an enclosed fluidic biochip with minimal maintenance. Three of the ten cell lines screened exhibited favorable portability characteristics on the biochips. Interestingly, all three cell lines were derived from ectothermic vertebrates, and the storage temperature that allowed long-term cell survival on the enclosed fluidic biochips was also at the lower end of reported body temperature for the organism, suggesting that reduced cellular metabolism may be essential for longterm survival on the biochip. Future work with the ectothermic vertebrate cells will characterize their sensitivity to a wide range of chemical toxicants to determine if they are good candidates for use in a field portable toxicity sensor.

Double trouble: rugby associated simultaneous rupture of flexor digitorum profundus tendon in zones I and III.

Sporting-related finger injuries are common in the setting of contact sports. Traumatic rupture of the flexor digitorum profundus tendon (FDP) from its insertion point has been described as 'jersey' or 'rugger' finger. We report a case of jersey finger associated with a zone III intra-tendinous rupture in a 13 year-old boy who presented seven weeks post injury. In the literature to date, only one previous case has described a sporting-related simultaneous 'double' FDP rupture.

Immunological responses to vaccination following experimental Lawsonia intracellularis virulent challenge in pigs.

Although a live attenuated vaccine has been used extensively to provide immunity against porcine proliferative enteropathy (PE) caused by Lawsonia intracellularis, the nature of the protective response is an area of considerable interest for the control of PE. Two trials investigated immune responses in pigs after oral and intramuscular (IM) vaccination followed by virulent L. intracellularis challenge. After an oral vaccination with 10(5.9) TCID50 organisms, significantly increased serum and mucosal secretions of IgM, IgG and higher mucosal TNF-α and TGF-ß1 were detected by day 17, together with a trend towards higher levels of IFN-γ and IL-6. Pigs vaccinated IM produced elevated serum antibody titres but mucosal immune responses were not detected. After challenge with virulent L. intracellularis, non-vaccinated control pigs had higher PE lesion scores and excreted significantly higher numbers of L. intracellularis in faeces than the vaccinated pigs. Reduced intestinal pathology and faecal L. intracellularis shedding were evident in the vaccinated groups. The results indicated that protection was associated with mucosal cytokine and specific IgG and IgA responses after vaccination and that systemic antibody responses were boosted following challenge. However in the search for an immune correlate with protection, a causal association was not evident from a kinetic analysis of immune parameters in serum, ileal pathology and faecal shedding.

Bare Below the Elbows: A comparative study of a tertiary and district general hospital.

A 'Bare Below the Elbows' (BBTE) dress code policy has been introduced by the majority of NHS trusts in the UK. The aim of this Irish study was to evaluate the impact of an educational intervention on perception of medical attire. The study was carried out in two centres: a tertiary referral centre (Beaumont Hospital) and a district hospital (MRH, Portlaoise). Two questionnaires, incorporating photographic evaluation of appropriate attire for consultants and junior doctors, were completed pre and post BBTE education. One hundred and five patients participated. Analysis pre BBTE education indicated patients considered formal attire and white coats most appropriate for consultants and junior doctors respectively. Post-intervention analysis revealed a significant reduction in the popularity of both (p <0.001), with scrubs and smart casual attire gaining significant support in both cohorts (p <0.001). Our findings demonstrated that patient opinion on medical attire is malleable. The support of such a policy may be achieved if patients are informed that the aim is to reduce the spread of healthcare-associated infections.

Providing supplemental milk to piglets preweaning improves the growth but not survival of gilt progeny compared with sow progeny.

Gilt progeny have lighter weaning weights and greater postweaning medication and mortality rates compared with the progeny of older parity sows. Because weaning weight has been positively correlated with postweaning survival, this study aimed to determine whether the provision of supplemental milk preweaning could improve weaning weight and subsequent weights as well as postweaning survival of gilt progeny. The study was replicated in summer and winter as the effects of supplemental milk were expected to vary with season. The progeny of 80 gilts (parity 0) and 80 sows (parity 2 to 5) were allocated to both treatments: with or without supplemental milk in these 2 seasons with 5 sheds/season. Litter size was standardized (10 to 11 piglets) and each piglet was weighed at birth, d 21, weaning (4 wk), and 10 wk of age. Medications and mortalities were recorded both preweaning and postweaning. Pigs were housed within treatment groups postweaning, and ADFI and G:F were measured. Gilt progeny were 200 g lighter at birth in both replicates (P < 0.001) and were 500 g lighter at weaning in the winter replicate (P < 0.05) compared with sow progeny. The provision of supplemental milk improved weaning weight for both gilt and sow progeny by 800 g in summer (P < 0.05) and by 350 g in winter (P < 0.05). This improvement in weaning weight had no effect on the incidence of death or disease in milk-supplemented progeny of either gilts or sows (P > 0.05). Supplemental milk disappearance (the daily difference between the volume of milk provided and the residue left in the drinker) was greater in summer than winter (by 130 mL/piglet d(-1); P < 0.05) as were the associated weaning weight benefits. The weaning weights of supplemented gilt progeny reached or exceeded that of nonsupplemented sow progeny. Gilt progeny had greater postweaning mortality (2.6%) and medication rates (6.2%) than sow progeny (1 and 2.2%, respectively; both P < 0.05) in both seasons, but medication rates were greater in winter (7.2%) for both treatment groups than in summer (1.9%; P < 0.05). Gilt progeny also had less postweaning ADFI than sow progeny in winter (528 and 636 g, respectively; P < 0.05) with no dam parity effect on G:F (both P > 0.05). The hypothesis that supplemental milk provision did increase gilt progeny weaning weight was supported (especially in summer) but the supplementation had no effect on postweaning weights and survival. Efforts to improve gilt progeny postweaning growth and survival need to be aimed at improving health and immunity, not just weaning weight.

Colonisation and shedding of Lawsonia intracellularis in experimentally inoculated rodents and in wild rodents on pig farms.

Lawsonia intracellularis is an intracellular bacterium causing proliferative enteropathy in various animal species, and is considered an economically important pathogen of pigs. Rats and mice have been implicated as external vectors for a wide range of pig pathogens, including L. intracellularis. Previous studies have demonstrated L. intracellularis infection and proliferative enteropathy in rodents, but did not show the duration of shedding or the number of L. intracellularis shed by infected rodents, and therefore the infection risk that rodents pose to pigs. In this study, the number of L. intracellularis shed in the faeces and intestinal mucosa of wild rats trapped on pig farms was determined by a quantitative real time polymerase chain reaction assay. The prevalence of L. intracellularis in wild rats trapped on pig farms with endemic proliferative enteropathy (PE) was very high (≥ 70.6%), and large numbers of L. intracellularis were shed (10(10)/g of faeces) in a small proportion of wild rats. The duration of colonisation in laboratory rats and mice challenged with porcine isolates of L. intracellularis was also shown. Faecal shedding of L. intracellularis persisted for 14-21 days in rats and mice that were mildly affected with histological lesions of PE. The humoral immune response to L. intracellularis persisted for 40 days in both species. This study demonstrates that rodents may be an important reservoir of L. intracellularis on piggeries, and hence rodent control is important in disease eradication programs on pig farms.