Multi-site and nasal swabbing for carriage of Staphylococcus aureus: what does a single nose swab predict?

BACKGROUND: Carriage of Staphylococcus aureus is a risk for infections. Targeted decolonization reduces postoperative infections but depends on accurate screening. AIM: To compare detection of S. aureus carriage in healthy individuals between anatomical sites and nurse- versus self-swabbing; also to determine whether a single nasal swab predicted carriage over four weeks. METHODS: Healthy individuals were recruited via general practices. After consent, nurses performed multi-site swabbing (nose, throat, and axilla). Participants performed nasal swabbing twice-weekly for four weeks. Swabs were returned by mail and cultured for S. aureus. All S. aureus isolates underwent spa typing. Persistent carriage in individuals returning more than three self-swabs was defined as culture of S. aureus from all or all but one self-swabs. FINDINGS: In all, 102 individuals underwent multi-site swabbing; S. aureus carriage was detected from at least one site from 40 individuals (39%). There was no difference between nose (29/102, 28%) and throat (28/102, 27%) isolation rates: the combination increased total detection rate by 10%. Ninety-nine patients returned any self-swab, and 96 returned more than three. Nasal carriage detection was not significantly different on nurse or self-swab [28/99 (74%) vs 26/99 (72%); χ2: P=0.75]. Twenty-two out of 25 participants with first self-swab positive were persistent carriers and 69/71 with first self-swab negative were not, giving high positive predictive value (88%), and very high negative predictive value (97%). CONCLUSION: Nasal swabs detected the majority of carriage; throat swabs increased detection by 10%. Self-taken nasal swabs were equivalent to nurse-taken swabs and predicted persistent nasal carriage over four weeks.

Cytokine network analysis of cerebrospinal fluid in myalgic encephalomyelitis/chronic fatigue syndrome.

Myalgic encephalomyelitis/chronic fatigue syndrome is an unexplained debilitating disorder that is frequently associated with cognitive and motor dysfunction. We analyzed cerebrospinal fluid from 32 cases, 40 subjects with multiple sclerosis and 19 normal subjects frequency-matched for age and sex using a 51-plex cytokine assay. Group-specific differences were found for the majority of analytes with an increase in cases of CCL11 (eotaxin), a chemokine involved in eosinophil recruitment. Network analysis revealed an inverse relationship between interleukin 1 receptor antagonist and colony-stimulating factor 1, colony-stimulating factor 2 and interleukin 17F, without effects on interleukin 1α or interleukin 1ß, suggesting a disturbance in interleukin 1 signaling. Our results indicate a markedly disturbed immune signature in the cerebrospinal fluid of cases that is consistent with immune activation in the central nervous system, and a shift toward an allergic or T helper type-2 pattern associated with autoimmunity.

A new economic instrument for financing accelerated landfill aftercare.

The key aspects of landfill operation that remain unresolved are the extended timescale and uncertain funding of the post-closure period. This paper reviews the topic and proposes an economic instrument to resolve the unsustainable nature of the current situation. Unsustainability arises from the sluggish degradation of organic material and also the slow flushing of potential pollutants that is exacerbated by low-permeability capping. A landfill tax or aftercare provision rebate is proposed as an economic instrument to encourage operators to actively advance the stabilization of landfilled waste. The rebate could be accommodated within existing regulatory and tax regimes and would be paid for: (i) every tonne of nitrogen (or other agreed leachate marker) whose removal is advanced via the accelerated production and extraction of leachate; (ii) every tonne of non-commercially viable carbon removed via landfill gas collection and treatment. The rebates would be set at a level that would make it financially attractive to operators and would encourage measures such as leachate recirculation, in situ aeration, and enhanced flushing. Illustrative calculations suggest that a maximum rebate of up to ∼€50/tonne MSW would provide an adequate incentive.

Cu(Ir1 - xCrx)2S4: a model system for studying nanoscale phase coexistence at the metal-insulator transition.

Increasingly, nanoscale phase coexistence and hidden broken symmetry states are being found in the vicinity of metal-insulator transitions (MIT), for example, in high temperature superconductors, heavy fermion and colossal magnetoresistive materials, but their importance and possible role in the MIT and related emergent behaviors is not understood. Despite their ubiquity, they are hard to study because they produce weak diffuse signals in most measurements. Here we propose Cu(Ir1 - xCrx)2S4 as a model system, where robust local structural signals lead to key new insights. We demonstrate a hitherto unobserved coexistence of an Ir(4+) charge-localized dimer phase and Cr-ferromagnetism. The resulting phase diagram that takes into account the short range dimer order is highly reminiscent of a generic MIT phase diagram similar to the cuprates. We suggest that the presence of quenched strain from dopant ions acts as an arbiter deciding between the competing ground states.

Multiple-strain colonization in nasal carriers of Staphylococcus aureus.

Staphylococcus aureus is a commensal that can also cause invasive infection. Reports suggest that nasal cocolonization occurs rarely, but the resources required to sequence multiple colonies have precluded its large-scale investigation. A staged protocol was developed to maximize detection of mixed-spa-type colonization while minimizing laboratory resources using 3,197 S. aureus-positive samples from a longitudinal study of healthy individuals in Oxfordshire, United Kingdom. Initial typing of pooled material from each sample identified a single unambiguous strain in 89.6% of samples. Twelve single-colony isolates were typed from samples producing ambiguous initial results. All samples could be resolved into one or more spa types using the protocol. Cocolonization point prevalence was 3.4 to 5.8% over 24 months of follow-up in 360 recruitment-positives. However, 18% were cocolonized at least once, most only transiently. Cocolonizing spa types were completely unrelated in 56% of samples. Of 272 recruitment-positives returning ≥12 swabs, 166 (61%) carried S. aureus continuously but only 106 (39%) carried the same single spa type without any cocolonization; 31 (11%) switched spa type and 29 (11%) had transient cocarriage. S. aureus colonization is dynamic even in long-term carriers. New unrelated cocolonizing strains could increase invasive disease risk, and ongoing within-host evolution could increase invasive potential, possibilities that future studies should explore.

Frequency-modulated orocutaneous stimulation promotes non-nutritive suck development in preterm infants with respiratory distress syndrome or chronic lung disease.

OBJECTIVE: For the premature infant, extrauterine life is a pathological condition, which greatly amplifies the challenges to the brain in establishing functional oromotor behaviors. The extent to which suck can be entrained using a synthetically patterned orocutaneous input to promote its development in preterm infants who manifest chronic lung disease (CLD) is unknown. The objective of this study was to evaluate the effects of a frequency-modulated (FM) orocutaneous pulse train delivered through a pneumatically charged pacifier capable of enhancing non-nutritive suck (NNS) activity in tube-fed premature infants. STUDY DESIGN: A randomized trial to evaluate the efficacy of pneumatic orocutaneous stimulation 3 × per day on NNS development and length of stay (LOS) in the neonatal intensive care unit among 160 newborn infants distributed among three sub-populations, including healthy preterm infants, respiratory distress syndrome (RDS) and CLD. Study infants received a regimen of orocutaneous pulse trains through a PULSED pressurized silicone pacifier or a SHAM control (blind pacifier) during gavage feeds for up to 10 days. RESULT: Mixed modeling, adjusted for the infant's gender, gestational age, postmenstrual age and birth weight, was used to handle interdependency among repeated measures within subjects. A significant main effect for stimulation mode (SHAM pacifier vs PULSED orosensory) was found among preterm infants for NNS bursts per min (P=0.003), NNS events per min (P=0.033) and for total oral compressions per min (NNS+nonNNS) (P=0.016). Pairwise comparison of adjusted means using Bonferroni adjustment indicated RDS and CLD infants showed the most significant gains on these NNS performance indices. CLD infants in the treatment group showed significantly shorter LOS by an average of 2.5 days. CONCLUSION: FM PULSED orocutaneous pulse train stimuli delivered through a silicone pacifier are effective in facilitating NNS burst development in tube-fed RDS and CLD preterm infants, with an added benefit of reduced LOS for CLD infants.

Attributions and self-efficacy for physical activity in multiple sclerosis.

Self-efficacy is an important predictor of health-related physical activity in multiple sclerosis (MS). While past experiences are believed to influence efficacy beliefs, the explanations individuals provide for these experiences also may be critical. Our objective was to test the hypothesis that perceived success or failure to accumulate 150 min of physical activity in the previous week would moderate the relationship between the attributional dimension of stability and self-efficacy to exercise in the future. Forty-two adults with MS participated in this cross-sectional descriptive study. Participants completed questions assessing physical activity, perceived outcome for meeting the recommended level of endurance activity, attributions for the outcome, and exercise self-efficacy. Results from hierarchical multiple regression revealed a significant main effect for perceived outcome predicting self-efficacy that was qualified by a significant interaction. The final model, which included perceived outcome, stability, and the interaction term, predicted 37% of the variance in exercise self-efficacy, F (3, 38) = 7.27, p = .001. Our findings suggest that the best prediction of self-efficacy in the MS population may include the interaction of specific attributional dimensions with success/failure at meeting the recommended physical activity dose. Attributions may be another target for interventions aimed at increasing the physical activity in MS.

Resprouting as a key functional trait: how buds, protection and resources drive persistence after fire.

Resprouting as a response to disturbance is now widely recognized as a key functional trait among woody plants and as the basis for the persistence niche. However, the underlying mechanisms that define resprouting responses to disturbance are poorly conceptualized. Resprouting ability is constrained by the interaction of the disturbance regime that depletes the buds and resources needed to fund resprouting, and the environment that drives growth and resource allocation. We develop a buds-protection-resources (BPR) framework for understanding resprouting in fire-prone ecosystems, based on bud bank location, bud protection, and how buds are resourced. Using this framework we go beyond earlier emphases on basal resprouting and highlight the importance of apical, epicormic and below-ground resprouting to the persistence niche. The BPR framework provides insights into: resprouting typologies that include both fire resisters (i.e. survive fire but do not resprout) and fire resprouters; the methods by which buds escape fire effects, such as thick bark; and the predictability of community assembly of resprouting types in relation to site productivity, disturbance regime and competition. Furthermore, predicting the consequences of global change is enhanced by the BPR framework because it potentially forecasts the retention or loss of above-ground biomass.

Clogging of landfill tyre and aggregate drainage layers by methanogenic leachate and implications for practice.

This paper reports the results of pilot scale tests carried out to investigate the clogging of shredded and baled tyres in comparison with aggregates when percolated by leachates representative of those generated by methanogenic stage landfills. Realistic lifetime loading rates of methanogenic leachate were applied, and clogging was not generally apparent in any of the drainage media studied. This is in apparent contrast to many other studies that have demonstrated the susceptibility of all forms of drainage media to biological and chemical clogging when percolated with high strength organic and calcium rich leachates. The reasons for this difference are identified, the implications for landfill drainage system design are discussed and some suggestions for operational practice are presented for discussion.

Transmission and control in an institutional pandemic influenza A(H1N1) 2009 outbreak.

A pandemic influenza A(H1N1) 2009 outbreak in a summer school affected 117/276 (42%) students. Residential social contact was associated with risk of infection, and there was no evidence for transmission associated with the classroom setting. Although the summer school had new admissions each week, which provided susceptible students the outbreak was controlled using routine infection control measures (isolation of cases, basic hygiene measures and avoidance of particularly high-risk social events) and prompt treatment of cases. This was in the absence of chemoprophylaxis or vaccination and without altering the basic educational activities of the school. Modelling of the outbreak allowed estimation of the impact of interventions on transmission. These models and follow-up surveillance supported the effectiveness of routine infection control measures to stop the spread of influenza even in this high-risk setting for transmission.

Systematic review: the relationship between interstitial lung diseases and gastro-oesophageal reflux disease.

BACKGROUND A potential relationship has been suggested between gastro-oesophageal reflux disease (GERD) and interstitial lung diseases (ILDs). AIM To evaluate whether there is a causal relationship between GERD and different ILDs. METHODS We conducted a systematic search of literature published between 1980 and 2010. After a review by two independent authors, each study was assigned an evidence-based rating according to a standard scoring system. RESULTS We identified 319 publications and 22 of them met the entry criteria. Of those, the relationship between GERD and idiopathic pulmonary fibrosis (IPF) was investigated in 14 articles, pulmonary involvement in systemic sclerosis (SSc) in six articles and pulmonary involvement in mixed connective tissue disease (MCTD) in two articles. We found the prevalence of GERD and/or oesophageal dysmotility to be higher in patients with different types of ILD as compared with those without ILD [Evidence B]. Among patients with IPF, 67-76% demonstrated abnormal oesophageal acid exposure off PPI treatment. No relationship was demonstrated between severity of GERD and severity of IPF [Evidence B]. Data are scant on outcomes of antireflux treatment in patients with IPF. There is a correlation between the severity of ILD and the degree of oesophageal motor impairment in patients with SSc and MCTD [Evidence B]. CONCLUSIONS Based on the currently available data, a causal relationship between GERD and idiopathic pulmonary fibrosis cannot be established. There is scant evidence about antireflux therapy in idiopathic pulmonary fibrosis patients. There may be an association between lung and oesophageal involvement in systemic sclerosis and mixed connective tissue disease, but a causal relationship cannot be established.

Global hormone profiling of murine placenta reveals Secretin expression.

OBJECTIVE: To elucidate and categorize the murine placental hormones expressed across gestation, including the expression of hormones with previously undescribed roles. STUDY DESIGN: Expression levels of all genes with known or predicted hormone activity expressed in two separate tissues, the placenta and maternal decidua, were assessed across a timecourse spanning the full lifetime of the placenta. Novel expression patterns were confirmed by in situ hybridization and protein level measurements. RESULTS: A combination of temporal and spatial information defines five groups that can accurately predict the patterns of uncharacterized hormones. Our analysis identified Secretin, a novel placental hormone that is expressed specifically by the trophoblast at levels many times greater than in any other tissue. CONCLUSIONS: The characteristics of Secretin fit the paradigm of known placental hormones and suggest that it may play an important role during pregnancy.

Leachate recirculation in a landfill: some insights obtained from the development of a simple 1-D model.

The re-introduction of leachate back into the waste can play an important part in landfill management. It can encourage biodegradation by raising the water content and transporting bacteria, nutrients and waste products. It also enables leachate to be stored within the body of the landfill, for example to help minimise temporal variations in the load on a leachate treatment plant. It is helpful for a landfill operator to be able to estimate the rate at which the landfill can accept leachate (the maximum infiltration or injection rate), the storage capacity of the landfill and the leachate retention time. This paper discusses some of the insights obtained from the development and application of a simple conceptual model of leachate recirculation that can be used to estimate key parameter values on the basis of the hydraulic properties of the waste. The model is described, partly validated against a more rigorous numerical analysis, and then used to interpret data obtained from field tests on a real site. The shortcomings of the model in its current form are discussed, and suggestions are made as to how these might be addressed in the context of developing the model as a design tool.

Nonequilibrium band mapping of unoccupied bulk states below the vacuum level by two-photon photoemission.

We demonstrate angle-resolved, tunable, two-photon photoemission (2PPE) to map a bulk unoccupied band, viz. the Cu sp band 0 to 1 eV below the vacuum level, in the vicinity of the L point. This short-lived bulk band is seen due to the strong optical pump rate, and the observed transition energies and their dispersion with photon energy ℏω, are in excellent agreement with tight-binding band-structure calculations. The variation of the final-state energy with ℏω has a measured slope of ∼1.64 in contrast to values of 1 or 2 observed for 2PPE from two-dimensional states. This unique variation illustrates the significant role of the perpendicular momentum ℏk_{⊥} in 2PPE.

'Feral' and 'wild'-type methicillin-resistant Staphylococcus aureus in the United Kingdom.

Circulation of methicillin-resistant Staphylococcus aureus (MRSA) outside hospitals could alter the impact of hospital-based control strategies. We investigated two groups of cases (each matched to controls with MRSA): 61 'community cases' not in acute hospital in the year before MRSA isolation; and 21 cases with ciprofloxacin-sensitive (CipS) MRSA. Multi-locus sequence typing, spa-typing and Panton-Valentine leukocidin gene testing were performed and demographics obtained. Additional questionnaires were completed by community case GPs. Community cases comprised 6% of Oxfordshire MRSA. Three community cases had received no regular healthcare or antibiotics: one was infected with CipS. Ninety-one percent of community cases had healthcare-associated sequence type (ST)22/36; CipS MRSA cases had heterogeneous STs but many had recent healthcare exposure. A substantial minority of UK MRSA transmission may occur outside hospitals. Hospital strains are becoming 'feral' or persisting in long-term carriers in the community with regular healthcare contacts; those with recent healthcare exposure may nevertheless acquire non-hospital epidemic MRSA strains in the community.

High frequencies of polyfunctional HIV-specific T cells are associated with preservation of mucosal CD4 T cells in bronchoalveolar lavage.

The mechanisms underlying the massive gastrointestinal tract CD4 T-cell depletion in human immunodeficiency virus (HIV) infection are not well understood nor is it clear whether similar depletion is manifest at other mucosal surfaces. Studies of T-cell and virus dynamics in different anatomical sites have begun to illuminate the pathogenesis of HIV-associated disease. Here, we studied depletion and HIV infection frequencies of CD4 T cells from the gastrointestinal tract, bronchoalveolar lavage (BAL), and blood with the frequencies and functional profiles of HIV-specific T cells in these anatomically distinct sites in HIV-infected individuals. The major findings to emerge were as follows: (i) depletion of gastrointestinal CD4 T cells is associated with high frequencies of infected CD4 T cells; (ii) HIV-specific T cells are present at low frequencies in the gastrointestinal tract compared to blood; (iii) BAL CD4 T cells are not massively depleted during the chronic phase; (iv) infection frequencies of BAL CD4 T cells are similar to those in blood; (v) significantly higher frequencies and increased functionality of HIV-specific T cells were observed in BAL compared to blood. Taken together, these data suggest mechanisms for mucosal CD4 T-cell depletion and interventions that might circumvent global depletion of mucosal CD4 T cells.

Performance characteristics of the platelia Aspergillus enzyme immunoassay for detection of Aspergillus galactomannan antigen in bronchoalveolar lavage fluid.

We have evaluated the Platelia Aspergillus enzyme immunoassay for detection of galactomannan in bronchoalveolar lavage (BAL) specimens in solid organ transplant patients with aspergillosis. The precision and reproducibility in serum or BAL to which galactomannan was added were similar. Sensitivity was 81.8% in patients with aspergillosis, and specificity was 95.8% in lung transplant patients who underwent BAL for surveillance for infection or rejection. Among transplant controls, positive results were more common in patients (i) who underwent diagnostic BAL performed for evaluation of symptoms or chest computed tomographic abnormalities, (ii) who had undergone lung transplantation, or (iii) who were colonized with Aspergillus. Galactomannan testing in BAL is useful for diagnosis of aspergillosis in transplant patients. The significance of positive results in patients without confirmed aspergillosis requires further evaluation.

HIV associated pulmonary emphysema: a review of the literature and inquiry into its mechanism.

Chronic lung diseases are increasingly recognised complications of the human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome (AIDS). Of these, pulmonary emphysema, characterised by permanent destruction of the lung parenchyma distal to the terminal bronchioles accompanied by various degrees of inflammation, is emerging as a distinct source of morbidity for patients infected with HIV. Similarly, HIV is now frequently cited as a susceptibility factor for the development of emphysema, independent of cigarette smoking status. The presence of common coexistent confounding factors that may predispose patients to chronic lung injury such as drugs, opportunistic infections and malnutrition, limits the scope of studies of direct mechanisms involved in HIV associated emphysematous lung disease. We review the clinical studies supporting a direct association between HIV infection and emphysema. Recent developments in the basic understanding of HIV infection and emphysema are also reviewed, since they may aid in understanding the pathobiology of HIV associated emphysema. The authors emphasise how HIV infection may affect cytotoxic lymphocyte activation, lung capillary endothelial cell injury and apoptosis, sphingolipid imbalance and oxidative stress in the lung. A better understanding of the pathogenesis of HIV associated pulmonary emphysema may provide clues and therapeutic targets that have broader application in this disease, including cigarette smoke induced emphysema.

Comparison of the time required to administer three different fluke and worm combination products to commercial beef cattle at housing.

Larger livestock units, a decline in the farm labor force, animal welfare concerns, and a trend toward more selective use of drugs have increased the focus on animal handling, time management, convenience, and compliance in administering veterinary therapeutics. This study was undertaken to quantify and compare the time needed to treat commercial beef cattle with three fluke and worm combination products with different administration profiles. Young beef cattle (n = 270) weighing approximately 400 kg were allocated to batches of five, which were randomly assigned to receive ivermectin + clorsulon injection, ivermectin + closantel injection, or levamisole + triclabendazole oral drench. The mean time needed to administer ivermectin + clorsulon (single injection) to five cattle was 31 seconds, which was significantly less than the 100 seconds needed for ivermectin + closantel (two injections) and the 126 seconds needed for levamisole + triclabendazole (P < .001). Such quantitative data can allow for better planning and selection of parasiticide treatment approaches at the farm level.

Effects of lidocaine and epinephrine on cutaneous blood flow.

BACKGROUND: Local anaesthetic agents in combination with epinephrine are frequently used in local reconstructive procedures such as skin tumour excision and local flap closure. The purpose of this study was to measure the effect of subdermal injection of lidocaine combined with epinephrine on cutaneous blood flow in the forearm and in the face. METHODS: Thirty injections were performed on the forearm and 40 injections were performed on the face in five healthy volunteers. In both anatomical regions, 0.9% phosphate buffered saline (PBS) was used as a control, and experimental injections included 1% lidocaine either alone or in combination with 1:100,000 epinephrine, and an additional combination of 1% lidocaine with 1:200,000 epinephrine used in the facial experiments. Cutaneous blood flow was measured indirectly using laser Doppler imaging (moorLDI-Mark 2). RESULTS: A statistically significant increase in blood flow was achieved with injection of lidocaine in the forearm compared to saline, whereas a non-statistically significant increase was achieved with saline injection compared to lidocaine in the face. This occurred in the first 5 min in the forearm and 2 min in the face. The addition of 1:100,000 epinephrine to lidocaine resulted in an immediate decrease in cutaneous blood flow which was maximal at 10 min in the forearm and 8 min in the face. This was statistically significant compared to all other injections except for the combination of 1:200,000 epinephrine with lidocaine, injected in the face. CONCLUSIONS: The vascularity of different anatomical areas may account for blood flow differences following injection with saline and lidocaine. Incisions should be delayed for 10 min in the forearm and 8 min in the face following lidocaine+epinephrine injection to allow maximal benefit to take effect. There were no significant differences between 1:100,000 and 1:200,000 epinephrine combined with lidocaine in facial injections his study.