Identification and characterisation of Staphylococcus aureus on low cost screen printed carbon electrodes using impedance spectroscopy

Staphylococcus aureus infections are a cause of significant morbidity and mortality, in addition to representing a considerable economic burden. The aim of this study was to explore a low cost screen printed electrode as a sensor for the detection of S. aureus using impedance spectroscopy. S. aureus was incubated in chambers containing the electrodes and the results analysed using a novel normalisation approach. These results show that it is possible to detect the presence of S. aureus in LB media after 30 minutes incubation of a 1% growth culture, in addition to being able to see immediate cell concentration dependent changes in 0.9% NaCl. These observations imply that a number of electrochemical mechanisms cause a change in the impedance as a result of the presence of S. aureus, including adsorption to the electrode surface and the metabolism of the bacteria during growth. The study suggests that this detection approach would be useful in a number of clinical scenarios where S. aureus leads to difficult to treat infections

Rapid detection of Proteus mirabilis using disposable electrochemical sensors

Proteus mirabilis is a Gram-negative pathogen frequently isolated from clinical infections, predominantly those of the catheterised urinary tract and wounds. The possibility of severe complications of infection means rapid diagnosis is desired. In current clinical practice the detection of infection relies upon observation of patient symptoms, sampling and laborious culturing procedures. Electrochemical impedance spectroscopy (EIS) has emerged as a potentially suitable technology for real-time infection monitoring, with both in-situ and point-of-care applications. The ability of these low-cost carbon sensors to detect P. mirabilis was therefore demonstrated. Rapid detection of this pathogen highlighted the potential for this technology to be successfully adopted into a realtime infection monitoring device

Alarmins in frozen shoulder: a molecular association between inflammation and pain

Background: The pathophysiological mechanisms behind proliferation of fibroblasts and deposition of dense collagen matrix in idiopathic frozen shoulder remain unclear. Alarmins (also known as danger signals) are endogenous molecules that are released into the extracellular milieu after infection or tissue injury and that signal cell and tissue damage. Purpose: To investigate whether the presence of alarmins is higher in patients with idiopathic frozen shoulder than in control subjects. Study Design: Controlled laboratory study. Methods: Shoulder capsule samples were collected from 10 patients with idiopathic frozen shoulder and 10 patients with unstable shoulders (control). The samples were stained with hematoxylin and eosin (H&E) and analyzed by immunohistochemistry using antibodies against alarmin molecules including high-mobility group protein B1 (HMGB1), interleukin 33, S100A8, S100A9, and the peripheral nerve marker PGP9.5. Immunoreactivities were rated in a blinded fashion from “none” to “strong.” Immunohistochemical distribution within the capsule was noted. Before surgery, patient-ranked pain frequency, severity, stiffness, and the range of passive shoulder motion were recorded and statistically analyzed. Results: Compared with control patients, patients with frozen shoulder had greater frequency and severity of self-reported pain (P = .02) and more restricted range of motion in all planes (P < .05). H&E-stained capsular tissue from frozen shoulder showed fibroblastic hypercellularity and increased subsynovial vascularity. Immunoreactivity of alarmins was significantly stronger in frozen shoulder capsules compared with control capsules (P < .05). Furthermore, the expression of the alarmin molecule HMGB1 significantly correlated (r > 0.9, P < .05) with the severity of patient-reported pain. Conclusion: This study demonstrates a potential role for key molecular danger signals in frozen shoulder and suggests an association between the expression of danger molecules and the pain experienced by patients

Electroencephalographic density spectral array monitoring during propofol/sevoflurane coadministration in children, an exploratory observational study

Introduction: Propofol and sevoflurane have a long history in pediatric anesthesia. Combining both drugs at low dose levels offers new opportunities. However, monitoring the hypnotic effects of this drug combination in children is challenging, because the currently available processed EEG-based systems are insufficiently validated in young children and the co-administration of anesthetics. This study investigated electroencephalographic density spectral array monitoring during propofol/sevoflurane coadministration with fixed sevoflurane- and variable propofol dosages. Patients and methods: We analyzed the density spectral array pattern recorded during propofol/sevoflurane anesthesia in pediatric patients from birth to 11 years of age. Data from 78 patients were suitable for analysis. The primary outcome parameter of this study was the correlation between variable propofol dosages and the expression of the four electroencephalogram frequency bands β, α, θ, and δ. The main secondary outcome parameters were the intra-operative total EEG power and the prevalence of burst suppression. Results: In patients above the age of 1 year, a dose-dependent correlation between the propofol dosage and the relative percentage of β (−12.2%, p &lt; 0.001) and δ (5.1%, p &lt; 0.001) was found. There was an age-dependent trend toward increasing mean EEG power, with the most significant increase in the first year of life. In 14.1% of our patients, at least one episode of burst suppression occurred. Conclusion: DSA-guided augmentation of propofol anesthesia with sevoflurane provides sufficient depth of anesthesia at doses usually considered sub-anesthetic in children, leading to less anesthetic drug exposure for the individual child.</p

Electroencephalographic density spectral array monitoring during propofol/sevoflurane coadministration in children, an exploratory observational study

Introduction: Propofol and sevoflurane have a long history in pediatric anesthesia. Combining both drugs at low dose levels offers new opportunities. However, monitoring the hypnotic effects of this drug combination in children is challenging, because the currently available processed EEG-based systems are insufficiently validated in young children and the co-administration of anesthetics. This study investigated electroencephalographic density spectral array monitoring during propofol/sevoflurane coadministration with fixed sevoflurane- and variable propofol dosages. Patients and methods: We analyzed the density spectral array pattern recorded during propofol/sevoflurane anesthesia in pediatric patients from birth to 11 years of age. Data from 78 patients were suitable for analysis. The primary outcome parameter of this study was the correlation between variable propofol dosages and the expression of the four electroencephalogram frequency bands β, α, θ, and δ. The main secondary outcome parameters were the intra-operative total EEG power and the prevalence of burst suppression. Results: In patients above the age of 1 year, a dose-dependent correlation between the propofol dosage and the relative percentage of β (−12.2%, p &lt; 0.001) and δ (5.1%, p &lt; 0.001) was found. There was an age-dependent trend toward increasing mean EEG power, with the most significant increase in the first year of life. In 14.1% of our patients, at least one episode of burst suppression occurred. Conclusion: DSA-guided augmentation of propofol anesthesia with sevoflurane provides sufficient depth of anesthesia at doses usually considered sub-anesthetic in children, leading to less anesthetic drug exposure for the individual child.</p

Maternal outcomes at 3 months after planned caesarean section versus planned vaginal birth for twin pregnancies in the Twin Birth Study: a randomised controlled trial

OBJECTIVE: To compare outcomes at 3 months post partum for women randomised to give birth by planned caesarean section (CS) or by planned vaginal birth (VB) in the Twin Birth Study (TBS). DESIGN: We invited women in the TBS to complete a 3-month follow-up questionnaire. SETTING: Two thousand and eight hundred and four women from 25 countries. POPULATION: Two thousand and five hundred and seventy women (92% response rate). METHODS: Women randomised between 13 December 2003 and 4 April 2011 in the TBS completed a questionnaire and outcomes were compared using an intention-to-treat approach. MAIN OUTCOME AND MEASURES: Breastfeeding, quality of life, depression, fatigue and urinary incontinence. RESULTS: We found no clinically important differences between groups in any outcome. In the planned CS versus planned VB groups, breastfeeding at any time after birth was reported by 84.4% versus 86.4% (P = 0.13); the mean physical and mental Short Form (36) Health Survey (SF-36) quality of life scores were 51.8 versus 51.6 (P = 0.65) and 46.7 versus 46.0 (P = 0.09), respectively; the mean Multidimensional Assessment of Fatigue score was 20.3 versus 20.8 (P = 0.14); the frequency of probable depression on the Edinburgh Postnatal Depression Scale was 14.0% versus 14.8% (P = 0.57); the rate of problematic urinary incontinence was 5.5% versus 6.4% (P = 0.31); and the mean Incontinence Impact Questionnaire-7 score was 20.5 versus 20.4 (P = 0.99). Partner relationships, including painful intercourse, were similar between the groups. CONCLUSION: For women with twin pregnancies randomised to planned CS compared with planned VB, outcomes at 3 months post partum did not differ. The mode of birth was not associated with problematic urinary incontinence or urinary incontinence that affected the quality of life. Contrary to previous studies, breastfeeding at 3 months was not increased with planned VB. TWEETABLE ABSTRACT: Planned mode of birth for twins doesn't affect maternal depression, wellbeing, incontinence or breastfeeding

An empirical bioethical examination of Norwegian and British doctors' views of responsibility and (de)prioritization in healthcare

In a world with limited resources, allocation of resources to certain individuals and conditions inevitably means fewer resources allocated to other individuals and conditions. Should a patient's personal responsibility be relevant to decisions re- garding allocation? In this project we combine the normative and the descriptive, conducting an empirical bioethical examination of how both Norwegian and British doctors think about principles of responsibility in allocating scarce healthcare re- sources. A large proportion of doctors in both countries supported including re- sponsibility for illness in prioritization decisions. This finding was more prominent in zero‐sum scenarios where allocation to one patient means that another patient is denied treatment. There was most support for incorporating prospective responsi- bility (through patient contracts), and low support for integrating responsibility into co‐payments (i.e. through requiring responsible patients to pay part of the costs of treatment). Finally, some behaviours were considered more appropriate grounds for deprioritization (smoking, alcohol, drug use)—potentially because of the certainty of impact and direct link to ill health. In zero‐sum situations, prognosis also influenced prioritization (but did not outweigh responsibility). Ethical implications are discussed. We argue that the role that responsibility constructs appear to play in doctors' decisions indicates a needs for more nuanced—and clear—policy. Such policy should account for the distinctions we draw between responsibility‐sensitive and prog- nostic justifications for deprioritization

Prospective intention-based lifestyle contracts: mHealth technology and responsibility in healthcare

As the rising costs of lifestyle-related diseases place increasing strain on public healthcare systems, the individual’s role in disease may be proposed as a healthcare rationing criterion. Literature thus far has largely focused on retrospective responsi- bility in healthcare. The concept of prospective responsibility, in the form of a life- style contract, warrants further investigation. The responsibilisation in healthcare debate also needs to take into account innovative developments in mobile health technology, such as wearable biometric devices and mobile apps, which may change how we hold others accountable for their lifestyles. Little is known about public atti- tudes towards lifestyle contracts and the use of mobile health technology to hold people responsible in the context of healthcare. This paper has two components. Firstly, it details empirical findings from a survey of 81 members of the United Kingdom general public on public attitudes towards individual responsibility and rationing healthcare, prospective and retrospective responsibility, and the acceptabil- ity of lifestyle contracts in the context of mobile health technology. Secondly, we draw on the empirical findings and propose a model of prospective intention-based lifestyle contracts, which is both more aligned with public intuitions and less ethi- cally objectionable than more traditional, retrospective models of responsibility in healthcare

Phosphorus supply affects long-term carbon accumulation in mid-latitude ombrotrophic peatlands

Ombrotrophic peatlands are a globally important carbon store and depend on atmospheric nutrient deposition to balance ecosystem productivity and microbial decomposition. Human activities have increased atmospheric nutrient fluxes, but the impacts of variability in phosphorus supply on carbon sequestration in ombrotrophic peatlands are unclear. Here, we synthesise phosphorus, nitrogen and carbon stoichiometric data in the surface and deeper layers of mid-latitude Sphagnum-dominated peatlands across Europe, North America and Chile. We find that long-term elevated phosphorus deposition and accumulation strongly correlate with increased organic matter decomposition and lower carbon accumulation in the catotelm. This contrasts with literature that finds short-term increases in phosphorus supply stimulates rapid carbon accumulation, suggesting phosphorus deposition imposes a threshold effect on net ecosystem productivity and carbon burial. We suggest phosphorus supply is an important, but overlooked, factor governing long-term carbon storage in ombrotrophic peatlands, raising the prospect that post-industrial phosphorus deposition may degrade this carbon sink

Immunity induced by a broad class of inorganic crystalline materials is directly controlled by their chemistry

There is currently no paradigm in immunology that enables an accurate prediction of how the immune system will respond to any given agent. Here we show that the immunological responses induced by members of a broad class of inorganic crystalline materials are controlled purely by their physicochemical properties in a highly predictable manner. We show that structurally and chemically homogeneous layered double hydroxides (LDHs) can elicit diverse human dendritic cell responses in vitro. Using a systems vaccinology approach, we find that every measured response can be modeled using a subset of just three physical and chemical properties for all compounds tested. This correlation can be reduced to a simple linear equation that enables the immunological responses stimulated by newly synthesized LDHs to be predicted in advance from these three parameters alone. We also show that mouse antigen-specific antibody responses in vivo and human macrophage responses in vitro are controlled by the same properties, suggesting they may control diverse responses at both individual component and global levels of immunity. This study demonstrates that immunity can be determined purely by chemistry and opens the possibility of rational manipulation