Tribes and tribulations: interdisciplinary eHealth in providing services for people with a traumatic brain injury (TBI)

Background

eHealth has potential for supporting interdisciplinary care in contemporary traumatic brain injury (TBI) rehabilitation practice, yet little is known about whether this potential is being realised, or what needs to be done to further support its implementation. The purpose of this study was to explore health professionals’ experiences of, and attitudes towards eHealth technologies to support interdisciplinary practice within rehabilitation for people after TBI.

Methods

A qualitative study using narrative analysis was conducted. One individual interview and three focus groups were conducted with health professionals (n = 17) working in TBI rehabilitation in public and private healthcare settings across regional and metropolitan New South Wales, Australia.

Results

Narrative analysis revealed that participants held largely favourable views about eHealth and its potential to support interdisciplinary practice in TBI rehabilitation. However, participants encountered various issues related to (a) the design of, and access to electronic medical records, (b) technology, (c) eHealth implementation, and (d) information and communication technology processes that disconnected them from the work they needed to accomplish. In response, health professionals attempted to make the most of unsatisfactory eHealth systems and processes, but were still mostly unsuccessful in optimising the quality, efficiency, and client-centredness of their work.

Conclusions

Attention to sources of disconnection experienced by health professionals, specifically design of, and access to electronic health records, eHealth resourcing, and policies and procedures related to eHealth and interdisciplinary practice are required if the potential of eHealth for supporting interdisciplinary practice is to be realised.

Bile acid aspiration associated with lung chemical profile linked to other biomarkers of injury after lung transplantation

Aspiration of gastrointestinal contents has been linked to worse outcomes following lung transplantation but uncertainty exists about underlying mechanisms. We applied high-resolution metabolomics of bronchoalveolar lavage fluid (BALF) in patients with episodic aspiration (defined by bile acids in the BALF) to identify potential metabolic changes associated with aspiration. Paired samples, one with bile acids and another without, from 29 stable lung transplant patients were studied. Liquid chromatography coupled to high-resolution mass spectroscopy was used to interrogate metabolomic contents of these samples. Data were obtained for 7068 ions representing intermediary metabolites, environmental agents and chemicals associated with microbial colonization. A substantial number (2302) differed between bile acid positive and negative samples when analyzed by false discovery rate at q = 0.01. These included pathways associated with microbial metabolism. Hierarchical cluster analysis defined clusters of chemicals associated with bile acid aspiration that were correlated to previously reported biomarkers of lung injury including T cell granzyme B level and the chemoattractants CXCL9 and CXCL10. These data specifically link bile acids presence in lung allografts to inflammatory pathways known to segregate with worsening allograft outcome, and provide additional mechanistic insight into the association between reflux and lung allograft injury.

Increased rates of adverse outcomes for gestational diabetes and pre-pregnancy diabetes in on-reserve First Nations Women in Ontario, Canada

AIMS

To compare the prevalence of diabetes in pregnancy, pregnancy care and adverse pregnancy outcomes in on-reserve First Nations women vs. non-First Nations women in Ontario, Canada.

METHODS

A retrospective population-based cohort study was performed. All 487368 live singleton hospital deliveries between 1 April 2002 and 31 March 2010 were identified. Outcomes were defined by linking mothers and infants to provincial healthcare administrative databases.

RESULTS

Diabetes in pregnancy was more prevalent in First Nations women (10.3 vs. 6.0%). They received less pregnancy care and had higher rates of adverse outcomes than non-First Nations women with diabetes.

CONCLUSIONS

First Nations women are at a higher risk of diabetes in pregnancy and adverse outcomes. This highlights the need for increased care for pregnant First Nations women.

High bandwidth differential amplifier for shock experiments

We developed a high bandwidth differential amplifier for gas gun shock experiments of low-resistance metals. The circuit has a bandwidth up to 1 GHz, and is capable of measuring signals of ≤1.5 V with a common mode rejection of 250 V. Conductivity measurements of gas gun targets are measured by flowing high currents through the targets. The voltage is measured across the target using a technique similar to a four-point probe. Because of the design of the current source and load, the target voltage is ∼250 V relative to ground. Since the expected voltage change in the target is <1 V, the differential amplifier must have a large common mode rejection. Various amplifying designs are shown, although the increased amplification decreases bandwidth. Bench tests show that the amplifier can withstand significant common mode dc voltage and measure 10 ns, and 50 mV signals.

Mach-Zehnder recording systems for pulsed power diagnostics

Fiber-optic transmission and recording systems, based on Mach-Zehnder modulators, have been developed and installed at the National Ignition Facility (NIF), and are being developed for other pulsed-power facilities such as the Z accelerator at Sandia, with different requirements. We present the design and performance characteristics for the mature analog links, based on the system developed for the Gamma Reaction History diagnostic at the OMEGA laser and at NIF. For a single detector channel, two Mach-Zehnders are used to provide high dynamic range at the full recording bandwidth with no gaps in the coverage. We present laboratory and shot data to estimate upper limits on the radiation effects as they impact recorded data quality. Finally, we will assess the technology readiness level for mature and developing implementations of Mach-Zehnder links for these environments.

Increased rates of adverse outcomes for gestational diabetes and pre-pregnancy diabetes in on-reserve First Nations Women in Ontario, Canada

AIMS

To compare the prevalence of diabetes in pregnancy, pregnancy care and adverse pregnancy outcomes in on-reserve First Nations women vs. non-First Nations women in Ontario, Canada.

METHODS

A retrospective population-based cohort study was performed. All 487368 live singleton hospital deliveries between 1 April 2002 and 31 March 2010 were identified. Outcomes were defined by linking mothers and infants to provincial healthcare administrative databases.

RESULTS

Diabetes in pregnancy was more prevalent in First Nations women (10.3 vs. 6.0%). They received less pregnancy care and had higher rates of adverse outcomes than non-First Nations women with diabetes.

CONCLUSIONS

First Nations women are at a higher risk of diabetes in pregnancy and adverse outcomes. This highlights the need for increased care for pregnant First Nations women.

The first measurements of soft x-ray flux from ignition scale Hohlraums at the National Ignition Facility using DANTE (invited)

The first 96 and 192 beam vacuum Hohlraum target experiments have been fielded at the National Ignition Facility demonstrating radiation temperatures up to 340 eV and fluxes of 20 TW/sr as viewed by DANTE representing an ∼20 times flux increase over NOVA/Omega scale Hohlraums. The vacuum Hohlraums were irradiated with 2 ns square laser pulses with energies between 150 and 635 kJ. They produced nearly Planckian spectra with about 30±10% more flux than predicted by the preshot radiation hydrodynamic simulations. To validate these results, careful verification of all component calibrations, cable deconvolution, and software analysis routines has been conducted. In addition, a half Hohlraum experiment was conducted using a single 2 ns long axial quad with an irradiance of ∼2×10(15) W/cm(2) for comparison with NIF Early Light experiments completed in 2004. We have also completed a conversion efficiency test using a 128-beam nearly uniformly illuminated gold sphere with intensities kept low (at 1×10(14) W/cm(2) over 5 ns) to avoid sensitivity to modeling uncertainties for nonlocal heat conduction and nonlinear absorption mechanisms, to compare with similar intensity, 3 ns OMEGA sphere results. The 2004 and 2009 NIF half-Hohlraums agreed to 10% in flux, but more importantly, the 2006 OMEGA Au Sphere, the 2009 NIF Au sphere, and the calculated Au conversion efficiency agree to ±5% in flux, which is estimated to be the absolute calibration accuracy of the DANTEs. Hence we conclude that the 30±10% higher than expected radiation fluxes from the 96 and 192 beam vacuum Hohlraums are attributable to differences in physics of the larger Hohlraums.

Comparison of toxicity of smoke from traditional and harm-reduction cigarettes using mouse embryonic stem cells as a novel model for preimplantation development

BACKGROUND

Embryonic stem cells (ESC), which originate from the inner cell mass of blastocysts, are valuable models for testing the effects of toxicants on preimplantation development. In this study, mouse ESC (mESC) were used to compare the toxicity of mainstream (MS) and sidestream (SS) cigarette smoke on cell attachment, survival and proliferation. In addition, smoke from a traditional commercial cigarette was compared with smoke from three harm-reduction brands.

METHODS

MS and SS smoke solutions were made using an analytical smoking machine and tested at three doses using D3 mESC plated on 0.2% gelatin. At 6 and 24 h, images were taken and the number of attached cells was evaluated.

RESULTS

Both MS and SS smoke from traditional and harm-reduction cigarettes inhibited cell attachment, survival and proliferation dose dependently. For all brands, SS smoke was more potent than MS smoke. However, removal of the cigarette filter increased the toxicity of MS smoke to that of SS smoke. Both MS and SS smoke from harm-reduction cigarettes were as inhibitory, or more inhibitory, than their counterparts from the traditional brand. When preimplantation mouse embryos were cultured for 1 h in MS or SS smoke solutions from a harm-reduction brand, blastomeres became apoptotic, in agreement with the data obtained using mESC.

CONCLUSIONS

mESC provide a valuable model for toxicological studies on the preimplantation stage of development and were used to show that MS and SS smoke from traditional and harm-reduction cigarettes are detrimental to embryonic cells prior to implantation.

Smoke from traditional commercial, harm reduction and research brand cigarettes impairs oviductal functioning in hamsters (Mesocricetus auratus) in vitro

BACKGROUND

Cigarette smoke from 2R1 research brand cigarettes and specific toxicants in smoke inhibit oviductal functioning. Our purpose was to test the hypothesis that smoke from commercial cigarettes, including harm reduction cigarettes, inhibits oviductal functioning and to measure the concentration of previously identified toxicants in smoke from research and commercial cigarettes.

METHODS

Mainstream (MS) and sidestream (SS) smoke solutions from two research, six traditional commercial and three harm reduction brands were tested in vitro using an oviductal assay that measures ciliary beat frequency, oocyte retrieval rate and smooth muscle contraction.

RESULTS

Generally, smoke from each brand of cigarette was inhibitory in the three oviductal bioassays. SS, the major component of environmental tobacco smoke, was usually more inhibitory than MS, the smoke inhaled by active smokers. Nine cigarette toxicants, previously shown to be highly inhibitory in the oviductal bioassays, were quantified in MS and SS. 4-Methylpyridine, which was inhibitory by itself in picomolar doses, was present in the highest concentration in MS and SS solutions from all brands tested. In general, toxicant concentrations were higher in SS than in MS solutions.

CONCLUSIONS

These data show that commercial brands of cigarettes, including harm reduction cigarettes, contain toxicants that inhibit biological processes in the oviduct and could affect reproductive outcomes.

A path planning approach for computing large-amplitude motions of flexible molecules

MOTIVATION

Motion is inherent in molecular interactions. Molecular flexibility must be taken into account in order to develop accurate computational techniques for predicting interactions. Energy-based methods currently used in molecular modeling (i.e. molecular dynamics, Monte Carlo algorithms) are, in practice, only able to compute local motions while accounting for molecular flexibility. However, large-amplitude motions often occur in biological processes. We investigate the application of geometric path planning algorithms to compute such large motions in flexible molecular models. Our purpose is to exploit the efficacy of a geometric conformational search as a filtering stage before subsequent energy refinements.

RESULTS

In this paper two kinds of large-amplitude motion are treated: protein loop conformational changes (involving protein backbone flexibility) and ligand trajectories to deep active sites in proteins (involving ligand and protein side-chain flexibility). First studies performed using our two-stage approach (geometric search followed by energy refinements) show that, compared to classical molecular modeling methods, quite similar results can be obtained with a performance gain of several orders of magnitude. Furthermore, our results also indicate that the geometric stage can provide highly valuable information to biologists.

AVAILABILITY

The algorithms have been implemented in the general-purpose motion planning software Move3D, developed at LAAS-CNRS. We are currently working on an optimized stand-alone library that will be available to the scientific community.

Odorant binding and conformational changes of a rat odorant-binding protein

Odorant-binding proteins (OBPs) are lipocalins secreted in the nasal mucus of vertebrates, which convey odorants to their neuronal receptors. We compared the binding properties of a recombinant rat OBP (OBP-1F) using a set of six odorants of various chemical structures. We examined the binding properties by both fluorescent probe competition and isothermal titration calorimetry. OBP-1F affinity constants, in the micromolar range, varied by more than one order of magnitude and were roughly correlated to the odorant size. The observed binding stoichiometry was found to be around one odorant per dimer. Using tyrosine differential spectroscopy, the binding of ligand was shown to induce local conformational changes. A three-dimensional structure of OBP-1F, modelled using the known structure of aphrodisin as template, allowed us to suggest the location of the observed structural changes outside of the binding pocket. These results are consistent with one binding site located in one of the two beta-barrels of the OBP-1F dimer and a subtle conformational change correlated with binding of an odorant molecule, which hampers uptake of a second odorant by the other hydrophobic pocket.

Putative implication of α-amylase loop 7 in the mechanism of substrate binding and reaction products release

Alpha-amylases are widespread endo-enzymes involved in the hydrolysis of internal alpha-(1,4) glycosidic linkages of starch polymers. Molecular modeling of amylose-amylase interactions is a step toward enzymatic mechanism understanding and rational design of new enzymes. From the crystallographic complex of barley alpha-amylase AMY2-acarbose, the static aspects of amylose-amylase docking have been characterized with a model of maltododecaose (DP12) (G. André, A. Buléon, R. Haser, and V. Tran, Biopolymers 1999, Vol. 50, pp. 751-762; G. André and V. Tran, Special Publication no. 246 1999, The Royal Society of Chemistry, H. J. Gilbert, G. J. Davies, B. Henrissat, and B. Svensson, Eds., Cambridge, pp. 165-174). These studies, consistent with the experimental subsite mapping (K. Bak-Jensen, G. André, V. Tran, and B. Svensson, Journal of Biological Chemistry, to be published), propose a propagation scheme for an amylose chain in the active cleft of AMY2. The topographical overview of alpha-amylases identified loop 7 as a conserved segment flanking the active site. Since some crystallographic experiments suspected its high flexibility, its putative motion was explored through a robotic scheme, an alternate route to dynamics simulations that consume CPU time. The present article describes the characteristics of the flexibility of loop 7: location and motion in AMY2. A back-and-forth motion with a large amplitude of more than 0.6 nm was evaluated. This movement could be triggered by two hinge residues. It results in the loop flipping over the active site to enhance the docking of the native helical substrate through specific interactions, it positions the catalytic residues, it distorts the substrate towards its transition state geometry, and finally monitors the release of the products after hydrolysis. The residues involved in the process are now rational mutation points in the hands of molecular biologists.

Geometric algorithms for the conformational analysis of long protein loops

The efficient filtering of unfeasible conformations would considerably benefit the exploration of the conformational space when searching for minimum energy structures or during molecular simulation. The most important conditions for filtering are the maintenance of molecular chain integrity and the avoidance of steric clashes. These conditions can be seen as geometric constraints on a molecular model. In this article, we discuss how techniques issued from recent research in robotics can be applied to this filtering. Two complementary techniques are presented: one for conformational sampling and another for computing conformational changes satisfying such geometric constraints. The main interest of the proposed techniques is their application to the structural analysis of long protein loops. First experimental results demonstrate the efficacy of the approach for studying the mobility of loop 7 in amylosucrase from Neisseria polysaccharea. The supposed motions of this 17-residue loop would play an important role in the activity of this enzyme.

Peracute onset of severe tumor lysis syndrome immediately after 4 Gy fractionated TBI as part of reduced intensity preparative regimen in a patient with T-ALL with high tumor burden

We report a 30-year-old patient with therapy-refractory T-ALL undergoing unrelated allogeneic PBSCT. He developed severe tumor lysis syndrome (TLS) with extreme biochemical changes, cardiac and neurological symptoms and dialysis-dependent acute renal failure after TBI (4 Gy) on the first day of reduced intensity conditioning (RIC) for unrelated allogeneic PBSCT. The patient's clinical condition was stabilized after beginning daily hemodialysis and treatment for disturbed electrolytes, metabolic acidosis and plasma coagulation, as well as reduction of uric acid by rasburicase. The conditioning therapy and the allogenic PBSCT were scheduled according to the preparative regimen. According to our knowledge, severe TLS induced by 4 Gy TBI has not been reported so far. Regimen-related toxicity using RIC regimen was mild, allowing 30-50% of the patients to have an entirely outpatient transplantation. However, we would like to point out that severe TLS could also complicate PBSCT using RIC regimens in patients with relatively radiation-sensitive malignancies and high tumor burden.

Toxic epidermal necrolysis: differential diagnosis of an epidermolytic dermopathy in a hematopoietic stem cell transplant recipient

Toxic epidermal necrolysis (TEN) is an epidermolytic skin disorder associated with drug administration. It is associated with an erythematous rash with full thickness epidermal loss and characteristic histology. A 35-year-old woman underwent allogeneic hematopoietic stem cell transplantation (HSCT) for severe aplastic anemia (SAA). She developed an acute epidermolytic rash and TEN was diagnosed on the basis of skin biopsy. In the HSCT setting, TEN should be thought of as an important differential diagnosis of epidermolytic dermopathies. The most distinctive diagnostic test in the differential diagnosis of these disorders is skin biopsy

A lipid transfer protein binds to a receptor involved in the control of plant defence responses

Lipid transfer proteins (LTPs) and elicitins are both able to load and transfer lipidic molecules and share some structural and functional properties. While elicitins are known as elicitors of plant defence mechanisms, the biological function of LTP is still an enigma. We show that a wheat LTP1 binds with high affinity sites. Binding and in vivo competition experiments point out that these binding sites are common to LTP1 and elicitins and confirm that they are the biological receptors of elicitins. A mathematical analysis suggests that these receptors could be represented by an allosteric model corresponding to an oligomeric structure with four identical subunits.

Analysis of a three-dimensional structure of Potato leafroll virus coat protein obtained by homology modeling

Viruses of the family Luteoviridae are ssRNA plant viruses that have particles that exhibit icosahedral symmetry. To identify the residues that might be exposed on the surface of the Potato leafroll virus (PLRV; genus Polerovirus, family Luteoviridae) capsid, and therefore involved in biological interactions, we performed a structural analysis of the PLRV coat protein (CP) on the basis of comparisons with protein sequences and known crystal structures of CPs of other viruses. The CP of PLRV displays 33% sequence similarity with that of Rice yellow mottle virus (genus Sobemovirus) when the sequences were aligned by using the hidden Markov model method. A structure model for PLRV CP was designed by protein homology modeling, using the crystal structure of RYMV as a template. The resulting model is consistent with immunological and site-directed mutagenesis data previously reported. On the basis of this model it is possible to predict some surface properties of the PLRV CP and also speculate about the structural evolution of small icosahedral viruses.