Poorly Differentiated Hepatocellular Carcinoma Cells Avoid Apoptosis by Interacting with T Cells via CD40-CD40L Linkage

Hepatocellular carcinoma (HCC) was associated with increased soluble CD40 levels in a previous study. This study aimed to investigate CD40's role in liver tumor progression. CD40 levels were examined in HCC patient tissues and various HCC cell lines, and their interaction with CD4+T cells was studied. RNA sequencing analysis was performed to explore the mechanisms of CD40 induction. Poorly differentiated HCC tumor tissues exhibited high membrane-bound CD40 expression, in contrast to nontumor areas. Poorly differentiated HCC cell lines showed high expression of membrane-bound CD40 with low CD40 promoter methylation, which was opposite of well-differentiated ones. Solely modulating CD40 expression in HCC cells exerted no direct consequences on cell growth or appearance. Interestingly, HLFs co-cultured with activated (CD40 ligand+) CD4+ T cells increased CD40 levels and showed a modest 3.2% dead cells, then increased to 10.9% underwent preneutralizing CD40 condition, whereas preblocking both CD40 and integrin α5β1 concomitantly caused only 1.9% cell death. RNA sequencing of co-cultured HLFs with activated CD4+ T cells revealed the up-regulation of interferon and immune-response pathways. Increased interferon-γ levels in the activated T-cell media stimulated the Janus kinase/signal transducer and activator of transcription 3 pathway, resulting in increased CD40 expression in HLF. Collectively, CD40 expression in poorly differentiated HCC cells prevents cell death by interacting with CD40 ligand in activated T cells. Targeting CD40 may represent a promising anticancer therapy.

A humanized orthotopic mouse model for preclinical evaluation of immunotherapy in Ewing sarcoma

The advent of novel cancer immunotherapy approaches is revolutionizing the treatment for cancer. Current small animal models for most cancers are syngeneic or genetically engineered mouse models or xenograft models based on immunodeficient mouse strains. These models have been limited in evaluating immunotherapy regimens due to the lack of functional human immune system. Development of animal models for bone cancer faces another challenge in the accessibility of tumor engraftment sites. Here, we describe a protocol to develop an orthotopic humanized mouse model for a bone and soft tissue sarcoma, Ewing sarcoma, by transplanting fresh human cord blood CD34+ hematopoietic stem cells into young NSG-SGM3 mice combined with subsequent Ewing sarcoma patient derived cell engraftment in the tibia of the humanized mice. We demonstrated early and robust reconstitution of human CD45+ leukocytes including T cells, B cells, natural killer cells and monocytes. Ewing sarcoma xenograft tumors successfully orthotopically engrafted in the humanized mice with minimal invasive procedures. We validated the translational utility of this orthotopic humanized model by evaluating the safety and efficacy of an immunotherapy antibody, magrolimab. Treatment with magrolimab induces CD47 blockade resulting in significantly decreased primary tumor growth, decreased lung metastasis and prolonged animal survival in the established humanized model. Furthermore, the humanized model recapitulated the dose dependent toxicity associated with the CD47 blockade as observed in patients in clinical trials. In conclusion, this orthotopic humanized mouse model of Ewing sarcoma represents an improved platform for evaluating immunotherapy in bone and soft tissue sarcoma, such as Ewing sarcoma. With careful design and optimization, this model is generalizable for other bone malignancies.

An exploration of mental health, stress and well-being concerns among health students undertaking rural placements in Australia during the early stages of the COVID-19 pandemic

INTRODUCTION

The emergence of COVID-19 in 2020 led to an increase in stressors for students on rural placements, but little is known about how this impacted their mental health and well-being.

OBJECTIVE

To explore self-reported mental health, stress and well-being concerns among allied health, nursing and medical students who completed a scheduled University Department of Rural Health (UDRH)-faciliated rural placement in Australia between February and October 2020 (n = 1066).

DESIGN

Cross-sectional design involving an online survey measuring mental health, stress and well-being concerns. The survey was distributed via email by the 16 UDRHs across Australia.

FINDINGS

A total of 42.9%, 63.8% and 41.1% of survey respondents reported concerns about their mental health, levels of stress and well-being, respectively, during the early stages of the pandemic. Multiple logistic regression models found clinical training, course progression and financial concerns were predictive of negative mental health, increased stress and reduced well-being, while feeling connected was predictive of positive mental health, reduced stress and increased well-being.

DISCUSSION

Universities, UDRHs and health placement sites all have a responsibility to support the mental health and well-being of students undertaking rural placements. This support needs to encompass strategies to reduce financial stress, protect learning opportunities and increase connectedness. Ensuring adequate resourcing and support for those providing rural placement opportunities will safeguard quality rural placements during times of pandemic disruption.

Pediatric versus adult high grade glioma: Immunotherapeutic and genomic considerations

High grade gliomas are identified as malignant central nervous tumors that spread rapidly and have a universally poor prognosis. Historically high grade gliomas in the pediatric population have been treated similarly to adult high grade gliomas. For the first time, the most recent classification of central nervous system tumors by World Health Organization has divided adult from pediatric type diffuse high grade gliomas, underscoring the biologic differences between these tumors in different age groups. The objective of our review is to compare high grade gliomas in the adult versus pediatric patient populations, highlighting similarities and differences in epidemiology, etiology, pathogenesis and therapeutic approaches. High grade gliomas in adults versus children have varying clinical presentations, molecular biology background, and response to chemotherapy, as well as unique molecular targets. However, increasing evidence show that they both respond to recently developed immunotherapies. This review summarizes the distinctions and commonalities between the two in disease pathogenesis and response to therapeutic interventions with a focus on immunotherapy.

Predicting thermodiffusion in simple binary fluid mixtures

The predictive capabilities of some existing theoretical models to quantify thermodiffusion have been investigated in this work. To do so, the tests have been performed on two model fluids, the hard-sphere and the Lennard-Jones (including spheres and dimers) ones, exploring different mixtures and thermodynamic conditions thanks to extensive molecular simulations. It has been confirmed that the thermal diffusion factor should be expressed as the sum of one term related to the isotope effect and one term related to the "chemical" effects and that a kinetic term is required to quantify thermodiffusion from the gas state to the liquid state. In addition, regarding the isotope effects, it has been obtained that none of the available theoretical models are able to yield a reasonable prediction relatively to the molecular simulations results and that the moment of inertia contribution is one order of magnitude smaller than the mass contribution in the liquid state. Finally, concerning the chemical effects, it has been shown the Shukla and Firoozabadi model, complemented with a kinetic term, is probably the most reasonable option to estimate the chemical contribution to the thermal diffusion factor, even if it fails in capturing the effect of the asymmetry in size and in shape between the species. Overall, this works confirms that there is still a lack of a generic model able to predict accurately thermal diffusion factors, or equivalently Soret coefficient, in simple binary mixtures from the gas state to the liquid state.

Disinfection and conditions associated with thermo-assisted drying and decontamination inconsistently produce negative PRRSV rRT-PCR results on metal surfaces

Because contaminated livestock trailers are a significant risk for transmitting viruses between herds, various methods of washing, disinfecting, and thermo-assisted drying and decontamination (TADD) have been evaluated for their effectiveness in inactivating porcine reproductive and respiratory syndrome virus (PRRSV) on contaminated surfaces. Information on when to expect negative qRT-PCR results after adequate trailer sanitation is lacking. The objective of this study was to evaluate whether there are conditions associated with washing-disinfectant-TADD procedures that will consistently produce a negative qRT-PCR result for the purpose of monitoring compliance with trailer sanitation and decontamination protocols for PRRSV on metal surfaces. 144 diamond plate aluminum coupons were spiked with PRRSV or phosphate-buffered saline (PBS) and treated with a designated disinfectant protocol. Disinfectants evaluated included multiple accelerated® hydrogen peroxide (AHP) disinfectants and a quaternary ammonium and glutaraldehyde combination disinfectant. Disinfectant was applied for 5 or 60 minutes of contact time at either 20 °C or -10 °C in a matrix of feces or PBS. All coupons were heated until the surface temperature of the coupon reached 71 °C and then held for 10 minutes to simulate TADD under field conditions. Post-treatment swabs for all treatment groups, except negative control groups, were positive by PRRSV qRT-PCR. Under the conditions evaluated in this study, consistently negative qRT-PCR results after treatments were not found. Therefore, for the purpose of monitoring compliance with trailer sanitation and decontamination protocols for PRRSV, alternatives to qRT-PCR should be explored.

Environmental Sampling for Avian Influenza Virus Detection in Commercial Layer Facilities

The present study was designed to evaluate the utility of environmental samples for convenient but accurate detection of avian influenza virus (AIV) in commercial poultry houses. First, environmental samples from AIV-negative commercial layer facilities were spiked with an H5N2 low pathogenic AIV and were evaluated for their effect on the detection of viral RNA immediately or after incubation at -20 C, 4 C, 22 C, or 37 C for 24, 48, or 72 hr. Second, Swiffer pads, drag swabs, and boot cover swabs were evaluated for their efficiency in collecting feces and water spiked with the H5N2 LPAIV under a condition simulated for a poultry facility floor. Third, environmental samples collected from commercial layer facilities that experienced an H5N2 highly pathogenic AIV outbreak in 2014-15 were evaluated for the effect of sampling locations on AIV detection. The half-life of AIV was comparable across all environmental samples but decreased with increasing temperatures. Additionally, sampling devices did not differ significantly in their ability to collect AIV-spiked environmental samples from a concrete floor for viral RNA detection. Some locations within a poultry house, such as cages, egg belts, house floor, manure belts, and manure pits, were better choices for sampling than other locations (feed trough, ventilation fan, and water trays) to detect AIV RNA after cleaning and disinfection. Samples representing cages, floor, and manure belts yielded significantly more PCR positives than the other environmental samples. In conclusion, environmental samples can be routinely collected from a poultry barn as noninvasive samples for monitoring AIV.

Transport Efficiency of Biofunctionalized Magnetic Particles Tailored by Surfactant Concentration

Controlled transport of surface-functionalized magnetic beads in a liquid medium is a central requirement for the handling of captured biomolecular targets in microfluidic lab-on-chip biosensors. Here, the influence of the physiological liquid medium on the transport characteristics of functionalized magnetic particles and on the functionality of the coupled protein is studied. These aspects are theoretically modeled and experimentally investigated for prototype superparamagnetic beads, surface-functionalized with green fluorescent protein immersed in buffer solution with different concentrations of a surfactant. The model reports on the tunability of the steady-state particle substrate separation distance to prevent their surface sticking via the choice of surfactant concentration. Experimental and theoretical average velocities are discussed for a ratchet-like particle motion induced by a dynamic external field superposed on a static locally varying magnetic field landscape. The developed model and experiment may serve as a basis for quantitative forecasts on the functionality of magnetic particle transport-based lab-on-chip devices.

Dynamic Crossover in Fluids: From Hard Spheres to Molecules

We propose a simple and generic definition of a demarcation reconciling structural and dynamic frameworks when combined with the entropy scaling framework. This crossover line between gas- and liquid-like behaviors is defined as the curve for which an individual property, the contribution to viscosity due to molecules' translation, is exactly equal to a collective property, the contribution to viscosity due to molecular interactions. Such a definition is shown to be consistent with the one based on the minima of the kinematic viscosity. For the hard sphere, this is shown to be an exact solution. For Lennard-Jones spheres and dimers and for some simple real fluids, this relation holds very well. This crossover line passes nearby the critical point, and for all studied fluids, it is well captured by the critical excess entropy curve for atomic fluids, emphasizing the link between transport properties and local structure.

Barriers and enablers to skill-mix in the oral health workforce: A systematic review

INTRODUCTION

In dentistry, the term "skill-mix" is used to describe the combinations of dentists and dental care professionals in delivering activities that are commonly established by their level of education, training and scope of practice. However, the literature has indicated an under-utilisation of skill-mix in the oral health care team. Further work is required to understand the poor uptake of skill-mix in oral health care and what could be done to address this issue.

OBJECTIVE

To identify and synthesise the available evidence on the barriers and enablers to skill-mix in the oral health workforce using a macro-, meso- and micro-level framework.

MATERIALS AND METHODS

The databases MEDLINE, CINAHL and Scopus between January 2010 to April 2020 were searched. Primary research studies published in English were included.

RESULTS

Thirty-two articles were included. Key barriers and enablers at each level of analysis were identified. Macro-level barriers and enablers included structural, regulatory and policy conditions and dental health care needs of populations. Meso-level barriers and enablers defined the parameters of service delivery and included workplace characteristics, referral systems and patterns, and workplace productivity and efficiency. Micro-level barriers and enablers pertained to the perceptions, attitudes, and social acceptability of stakeholders that affected the delivery of services.

CONCLUSION

Understanding the barriers and enablers from a multi-level framework requires further high-quality research to fully appreciate its importance in addressing health care needs within populations and increase generalisability to oral health settings.

Seizures in autoimmune encephalitis-A systematic review and quantitative synthesis

OBJECTIVE

This study aimed to evaluate the proportion of patients with seizures and electroencephalography (EEG) abnormalities in autoimmune encephalitis (AE) and its most common subtypes.

METHODS

This systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) standards and was registered with the International Prospective Register of Systematic Reviews (PROSPERO). We searched Medline All, Embase, and PsychINFO in Ovid from inception to June 2019 for articles pertaining to AE and seizure. Included studies reported seizure and/or EEG data in cohorts of ≥10 AE patients. Patient demographics, antibody type, seizure incidence, and EEG findings were extracted. Review of studies and data extraction were performed in duplicate. In addition to descriptive analysis, quantitative synthesis stratified by autoantibody subtype was performed with logistic regression and chi-square analyses.

RESULTS

Our search yielded 3856 abstracts: 1616 were selected for full-text review and 118 studies met eligibility criteria. Of 3722 antibody-positive AE patients, 2601 (69.9%) had clinical seizures during the course of their illness. Of the 2025 patients with antibody-positive AE and available EEG data, 1718 (84.8%) had some EEG abnormality (eg, epileptiform discharges, slowing, and so on). Anti- N-methyl-d-aspartate (NMDA) receptor encephalitis (anti-NMDARE) was the most commonly reported type of AE (1985/3722, 53.3%). Of the anti-NMDARE patients with available seizure or EEG data, 71.8% (n = 1425/1985) had clinical seizures during their illness, and 89.7% (n = 1172/1306) had EEG abnormalities. For all AE patients and in the anti-NMDARE subpopulation, seizures were more common in younger patients (p < .05).

SIGNIFICANCE

This systematic review provides an estimate of the proportion of AE patients with seizures, confirming the magnitude of seizure burden in this population. Prospective studies are needed to understand population-based prevalence of seizures, identify factors associated with seizures, and evaluate particular EEG findings as biomarkers of seizures and outcomes in AE.

Economic development and human ties in informal food waste recycling: A follow-up study in Da Nang, Vietnam

This study examined the effects of economic development on the commercialised and non-commercialised segments of informal food waste recycling in Da Nang City, Vietnam. Food waste was collected from the urban centre and used as pig feed in swine farms in suburban areas. The commercialised and non-commercialised segments of this system have evolved differently over time. During our observation period of 2011-2016, swine farmers became concerned about economic efficiency, which affected the manner in which they used food waste. By 2016, more farmers had begun to use food waste brokers instead of collecting food waste themselves so that they could concentrate on rearing pigs. The price of food waste remained low, reflecting the farmers' need for low-cost feeding. This resulted in the closure of commercialised transactions between households and waste collectors amid increased household income. Instead, non-commercialised transactions supported by human ties became the main mode of household participation in food waste recycling . Our findings can guide the use of different elements in this informal recycling system within the framework of a formalised recycling system implemented by the government.

The Risk of Depression and Anxiety in the Post-diagnostic Period of Multiple Sclerosis Measured by Screening Instruments and Structured Interviews

Objective

To examine the risk of depression and anxiety in MS patients in the post-diagnostic period by using clinical screening instruments and a diagnostic structured clinical interview.

Method

A population of 134 MS patients was examined for the risk of depression and anxiety in the post-diagnostic period of MS using the clinical screening instruments Beck Depression Inventory (BDI) and Hospital Anxiety and Depression Scale (HADS). Within six weeks of diagnosis, patients with cut-off > 12 for BDI and > 7 for HADS were offered a clinical structured interview using the Schedules for Clinical Assessment in Neuropsychiatry/SCAN Version 2.1.

Results

The prevalence of depressive symptoms and depression in the post-diagnostic period of MS was 49.2% when using the screening instruments, but only 15.2% when using the SCAN interview. For anxiety, the prevalence was 3.4% for both the screening instruments and the SCAN interview in the post-diagnostic period of MS.

Conclusion

MS patients have a risk of depression and anxiety in the post-diagnostic period of MS, but it is crucial to consider which tools to use in a clinical setting to investigate depression and anxiety in MS patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Detection of live attenuated influenza vaccine virus and evidence of reassortment in the U.S. swine population

Influenza vaccines historically have been multivalent, whole virus inactivated products. The first bivalent, intranasal, live attenuated influenza vaccine (LAIV; Ingelvac Provenza), with H1N1 and H3N2 subtypes, has been approved for use in swine. We investigated the LAIV hemagglutinin (HA) sequences in diagnostic cases submitted to the Iowa State University Veterinary Diagnostic Laboratory and potential vaccine virus reassortment with endemic influenza A virus (IAV) in swine. From January 3 to October 11, 2018, IAV HA sequences demonstrating 99.5-99.9% nucleotide homology to the H1 HA or 99.4-100% nucleotide homology to the H3 HA parental strains in the LAIV were detected in 58 of 1,116 (5.2%) porcine respiratory cases (H1 HA A/swine/Minnesota/37866/1999[H1N1; MN99]; H3 HA A/swine/Texas/4199-2/1998[H3N2; TX98]). Nine cases had co-detection of HA genes from LAIV and wild-type IAV in the same specimen. Thirty-five cases had associated epidemiologic information that indicated they were submitted from 11 states representing 31 individual sites and 17 production systems in the United States. Whole genome sequences from 11 cases and another subset of 2 plaque-purified IAV were included in our study. Ten whole genome sequences, including 1 plaque-purified IAV, contained at least one internal gene from endemic IAV detected within the past 3 y. Phylogenetic analysis of whole genome sequences indicated that reassortment occurred between vaccine virus and endemic field strains circulating in U.S. swine. Our data highlight the need and importance of continued IAV surveillance to detect emerging IAV with LAIV genes in the swine population.

European Space Agency experiments on thermodiffusion of fluid mixtures in space

This paper describes the European Space Agency (ESA) experiments devoted to study thermodiffusion of fluid mixtures in microgravity environment, where sedimentation and convection do not affect the mass flow induced by the Soret effect. First, the experiments performed on binary mixtures in the IVIDIL and GRADFLEX experiments are described. Then, further experiments on ternary mixtures and complex fluids performed in DCMIX and planned to be performed in the context of the NEUF-DIX project are presented. Finally, multi-component mixtures studied in the SCCO project are detailed.

Aboriginal community understandings of dementia and responses to dementia care

OBJECTIVE

Aboriginal people and Torres Strait Islanders are impacted by dementia at higher rates and at a younger age of onset than the broader Australia population. Public health strategies to support this population require a thorough understanding of how Aboriginal people perceive dementia and dementia care support needs. The aim of this study was to investigate Aboriginal community understandings of dementia and their responses to dementia care.

STUDY DESIGN

This study is a community participatory action research partnership.

METHODS

The mixed method study was undertaken in 2017 with members of a discrete Aboriginal community from rural Tasmania, Australia. Participants were older than 18 years, self-identified as an Aboriginal person and were living or had lived in the community studied. Data were derived from 50 participants who completed the 27-item Dementia Knowledge Assessment Scale (DKAS). Twelve of these participants also shared their dementia care experiences in individual interviews.

RESULTS

The DKAS results showed a low overall level of dementia knowledge, with a total mean score of 27.73 (scoring 51% on average) of a possible score of 54. The salient interview theme was the cultural obligation to care for family members living with dementia. Dementia care metaphors represented ways to protect family members living with dementia and maintain their ongoing connections to home and community. However, limited understandings of dementia affected their capacity to provide quality care.

CONCLUSION

The findings contribute to public health scholarship involving Aboriginal community responses to dementia care. The study has resulted in important initiatives including a community-based dementia education program to ensure Aboriginal people impacted by dementia are provided with effective and culturally appropriate care.

Linking up pressure, chemical potential and thermal gradients

Petroleum reservoirs are remarkable illustrations of the impact of a thermal gradient on fluid pressure and composition. This topic has been extensively studied during the last decades to build tools that are required by reservoir engineers to populate their models. However, one can get only a very limited number of representative samples from a given reservoir and assessing connectivity between all sampling points is often a key issue. In some extreme cases, the whole reservoir fluid properties must be derived from a single point to define the field development plan. To do so, available models are usually not satisfactory as they need too many parameters and so cannot be considered as predictive tools. We propose in this work a comprehensive approach based on the irreversible thermodynamics principles to derive the relationships between pressure, chemical potentials and thermal gradients in porous media. It appears that there is no need for additional assumptions, it is just a matter of a making the right choices along theoretical developments. One of the most important steps is to express the full pressure gradient. As a final result, we obtain the chemical potential gradients for all components of the mixtures that can be easily translated in term of compositions through Equation of State modelling. The most important features of the final expressions are: i) the species relative separation in a thermal field is sensitive to the relative diffusion coefficients at stationary state. In porous media, the separation is sensitive to the permeability when the overall mobility is similar to diffusive mobility; ii) the magnitude of the separation depends on the residual entropy of the species; iii) the separation is not simply balanced by the average residual entropy. The balance is modified by the relative diffusion mobility of the components; iv) in low permeability porous media, the thermal gradient induces a pressure gradient proportional to the fluid residual entropy. As a validation, the proposed approach has been applied on a reservoir fluid subjected to a geothermal gradient and compared with non-equilibrium molecular dynamics simulation results at the stationary state.

Elemental and isotopic fractionation of noble gases in gas and oil under reservoir conditions: Impact of thermodiffusion⋆

Noble gases, and the way they fractionate, is a promising approach to better constrain origin, migration and initial state distributions of fluids in gas and oil reservoirs. Thermodiffusion, is one of the phenomena that may lead to isotope and elemental fractionation of noble gases. However, this effect, assumed to be small, has not been quantified, nor measured, in oil and gas under reservoir conditions. Thus, in this work, molecular dynamics simulations have been performed to compute the thermal diffusion factors of noble gases, in a dense gas (methane) and in an oil (n-hexane) under high pressures. Interestingly, it has been found that thermal diffusion factors, associated to both isotopic (³⁶Ar, ⁴⁰Ar) and elemental fractionations of noble gases (⁴He, ²⁰Ne, ⁴⁰Ar, ⁸⁴Kr and ¹³¹Xe) in gas and oil, could be expressed as linear functions of the reduced masses. Regarding the amplitude of the phenomena, it has been found that, in a stationary 1D oil or gas fluid column, thermodiffusion due to a typical geothermal gradient has an impact on noble gas isotopic and elemental fractionation which is of the same order of magnitude than gravity segregation, but opposite in sign. In addition, the relative impact of thermodiffusion on isotopic and elemental fractionations depends on the fluid type which is another interesting feature. Thus, these first numerical results on isotopic and elemental fractionation of noble gases by thermodiffusion in simple pure gas and oil emphasize their interest as natural tracers that could be used to improve the pre-exploitation description of oil and gas reservoirs.

Dexamethasone treatment did not exacerbate Seneca Valley virus infection in nursery-age pigs

BACKGROUND

Senecavirus A, commonly known as Seneca Valley virus (SVV), is a picornavirus that has been infrequently associated with porcine idiopathic vesicular disease (PIVD). In late 2014 there were multiple PIVD outbreaks in several states in Brazil and samples from those cases tested positive for SVV. Beginning in July of 2015, multiple cases of PIVD were reported in the United States in which a genetically similar SVV was also detected. These events suggested SVV could induce vesicular disease, which was recently demonstrated with contemporary US isolates that produced mild disease in pigs. It was hypothesized that stressful conditions may exacerbate the expression of clinical disease and the following experiment was performed. Two groups of 9-week-old pigs were given an intranasal SVV challenge with one group receiving an immunosuppressive dose of dexamethasone prior to challenge. After challenge animals were observed for the development of clinical signs and serum and swabs were collected to study viral shedding and antibody production. In addition, pigs were euthanized 2, 4, 6, 8, and 12 days post inoculation (dpi) to demonstrate tissue distribution of virus during acute infection.

RESULTS

Vesicular disease was experimentally induced in both groups with the duration and magnitude of clinical signs similar between groups. During acute infection [0-14 days post infection (dpi)], SVV was detected by PCR in serum, nasal swabs, rectal swabs, various tissues, and in swabs from ruptured vesicles. From 15 to 30 dpi, virus was less consistently detected in nasal and rectal swabs, and absent from most serum samples. Virus neutralizing antibody was detected by 5 dpi and lasted until the end of the study.

CONCLUSION

Treatment with an immunosuppressive dose of dexamethasone did not drastically alter the clinical disease course of SVV in experimentally infected nursery aged swine. A greater understanding of SVV pathogenesis and factors that could exacerbate disease can help the swine industry with control and prevention strategies directed against this virus.

Vesicular Disease in 9-Week-Old Pigs Experimentally Infected with Senecavirus A

Senecavirus A has been infrequently associated with vesicular disease in swine since 1988. However, clinical disease has not been reproduced after experimental infection with this virus. We report vesicular disease in 9-week-old pigs after Sencavirus A infection by the intranasal route under experimental conditions.

Thermodiffusion in multicomponent n-alkane mixtures

Compositional grading within a mixture has a strong impact on the evaluation of the pre-exploitation distribution of hydrocarbons in underground layers and sediments. Thermodiffusion, which leads to a partial diffusive separation of species in a mixture due to the geothermal gradient, is thought to play an important role in determining the distribution of species in a reservoir. However, despite recent progress, thermodiffusion is still difficult to measure and model in multicomponent mixtures. In this work, we report on experimental investigations of the thermodiffusion of multicomponent n-alkane mixtures at pressure above 30 MPa. The experiments have been conducted in space onboard the Shi Jian 10 spacecraft so as to isolate the studied phenomena from convection. For the two exploitable cells, containing a ternary liquid mixture and a condensate gas, measurements have shown that the lightest and heaviest species had a tendency to migrate, relatively to the rest of the species, to the hot and cold region, respectively. These trends have been confirmed by molecular dynamics simulations. The measured condensate gas data have been used to quantify the influence of thermodiffusion on the initial fluid distribution of an idealised one dimension reservoir. The results obtained indicate that thermodiffusion tends to noticeably counteract the influence of gravitational segregation on the vertical distribution of species, which could result in an unstable fluid column. This confirms that, in oil and gas reservoirs, the availability of thermodiffusion data for multicomponent mixtures is crucial for a correct evaluation of the initial state fluid distribution.

Benefits and Limitations of Text Messages to Stimulate Higher Learning Among Community Providers: Participants' Views of an mHealth Intervention to Support Continuing Medical Education in Vietnam

The original intention was to deliver technical content through brief text messages to stimulate participants to undertake deeper learning. While participants appreciated the convenience and relevance of the text messages, their scores of higher-order knowledge did not improve. The intervention may not have been successful because the messages lacked depth and interactivity, and participants were not explicitly encouraged to seek deeper learning.

Background:

A randomized controlled trial was conducted in 2015 to evaluate a mobile continuing medical education (mCME) intervention that provided daily text messages to community-based physicians' assistants (CBPAs) in Thai Nguyen Province, Vietnam. Although the intervention failed to improve medical knowledge over a 6-month period, a companion qualitative study provided insights on the views and experiences of intervention participants.

Methods:

We conducted focus group discussions (FGDs) and in-depth interviews (IDIs) among participants randomized to receive text messages containing either simple medical facts or quiz questions. Trained interviewers collected data immediately following the conclusion of the trial in December 2015. Using semi-structured question guides, respondents were queried on their views of the intervention, positive and negative, and perceived impacts of the intervention. During analysis, after learning that the intervention had failed to increase knowledge among participants, we also examined reasons for lack of improvement in medical knowledge. All analyses were performed in NVivo using a thematic approach.

Results:

A total of 70 CBPAs engaged in one of 8 FGDs or an IDI. One-half were men; average age among all respondents was 40 years. Most (81%) practiced in rural settings and most (51%) focused on general medicine. The mean length of work experience was 3 years. All respondents made positive comments about the intervention; convenience, relevance, and quick feedback (quiz format) were praised. Downsides encompassed lack of depth of information, weak interaction, technology challenges, and challenging/irrelevant messages. Respondents described perceived impacts encompassing increased motivation, knowledge, collegial discussions, Internet use to search for more information, and clinical skills. Overall, they expressed a desire for the intervention to continue and recommended expansion to other medical professionals. Overreliance on the text messages, lack of effective self-study, and technical/language-based barriers may be potential explanations for intervention failure.

Conclusion:

As a form of mCME, daily text messages were well-received by community-level health care providers in Vietnam. This mCME approach appears very promising in low-resource environments or where traditional forms of CME are impractical. Future models might consider enhancements to foster linkages to relevant medical materials, improve interaction with medical experts, and tailor medical content to the daily activities of medical staff.

The mCME Project: A Randomized Controlled Trial of an SMS-Based Continuing Medical Education Intervention for Improving Medical Knowledge among Vietnamese Community Based Physicians' Assistants

Background

Community health workers (CHWs) provide critical services to underserved populations in low and middle-income countries, but maintaining CHW’s clinical knowledge through formal continuing medical education (CME) activities is challenging and rarely occurs. We tested whether a Short Message Service (SMS)-based mobile CME (mCME) intervention could improve medical knowledge among a cadre of Vietnamese CHWs (Community Based Physician’s Assistants–CBPAs) who are the leading providers of primary medical care for rural underserved populations.

Methods

The mCME Project was a three arm randomized controlled trial. Group 1 served as controls while Groups 2 and 3 experienced two models of the mCME intervention. Group 2 (passive model) participants received a daily SMS bullet point, and were required to reply to the text to acknowledge receipt; Group 3 (interactive model) participants received an SMS in multiple choice question format addressing the same thematic area as Group 2, entering an answer (A, B, C or D) in their response. The server provided feedback immediately informing the participant whether the answer was correct. Effectiveness was based on standardized examination scores measured at baseline and endline (six months later). Secondary outcomes included job satisfaction and self-efficacy.

Results

638 CBPAs were enrolled, randomized, and tested at baseline, with 592 returning at endline (93.7%). Baseline scores were similar across all three groups. Over the next six months, participation of Groups 2 and 3 remained high; they responded to >75% of messages. Group 3 participants answered 43% of the daily SMS questions correctly, but their performance did not improve over time. At endline, the CBPAs reported high satisfaction with the mCME intervention, and deemed the SMS messages highly relevant. However, endline exam scores did not increase over baseline, and did not differ between the three groups. Job satisfaction and self-efficacy scores also did not improve. Average times spent on self-study per week did not increase, and the kinds of knowledge resources used by the CBPAs did not differ between the three groups; textbooks, while widely available, were seldom used.

Conclusions

The SMS-based mCME intervention, while feasible and acceptable, did not result in increased medical knowledge. We hypothesize that this was because the intervention failed to stimulate lateral learning. For an intervention of this kind to be effective, it will be essential to find more effective ways to couple SMS as a stimulus to promote increased self-study behaviors.

Trial Registration

ClinicalTrials.gov NCT02381743

Evidence of the effect of rural background on rural practise in Australian dental practitioners: Does gender play a role?

BACKGROUND

People residing outside the capital cities have poorer oral health than their city counterparts. Health workforce shortages and stability issues can have negative health effects on rural populations. There has been an increasing proportion of women entering the dental practitioner workforce in Australia. This study investigated whether dental practitioners who have a rural background are more likely to work in a rural area than those who do not have a rural background; and whether the gender of dental practitioners plays a role.

METHODS

A self-administered questionnaire was sent to a sample of dental practitioners via their professional dental associations. Practice location was assigned as either 'urban' or 'rural' using the Australian Standard Geographical Classification - Remoteness Area categories and measured with demographic characteristics of the respondents. Prevalence ratios (PR) were estimated using Poisson regression with robust standard errors.

RESULTS

Participants with a rural background were more than twice as likely (male PR = 2.23, 95% confidence interval (CI) = 0.79-6.26; female PR = 2.82, 95% CI = 1.35-5.87) to practise in a rural area than those with an urban background.

CONCLUSIONS

Dental practitioners with rural backgrounds were more than twice as likely to work in a rural practice as their urban counterparts.

Characterization of Porcine Epidemic Diarrhea Virus Isolate US/Iowa/18984/2013 Infection in 1-Day-Old Cesarean-Derived Colostrum-Deprived Piglets

Porcine epidemic diarrhea virus (PEDV) was first recognized in North America in April 2013 and has since caused devastating disease. The objective of this study was to characterize disease and viral detection associated with an original North American PEDV isolate inoculated in neonatal piglets. Thirty-six 1-day-old cesarean-derived and colostrum-deprived piglets were randomly assigned to the control (n = 16) or challenged group (n = 20); the latter were orogastrically inoculated with 1 ml of US/Iowa/18984/2013 PEDV isolate titered at 1 × 10(3) plaque-forming units per milliliter. Rectal swabs were collected from all piglets prior to inoculation and every 12 hours postinoculation (hpi) thereafter, with 4 control and 5 challenged piglets euthanized at 12, 24, 48, and 72 hpi. One piglet had a positive real-time quantitative polymerase chain reaction test on rectal swab at 12 hpi, and all remaining piglets were positive thereafter, with highest viral quantities detected at 24 and 36 hpi. Diarrhea was evident in 30% and 100% of challenged piglets at 18 and 24 hpi, respectively. Viral antigen was detected in enterocytes by immunohistochemistry in the duodenum and ileum of piglets euthanized at 12 hpi and was apparent throughout the small intestine of all piglets thereafter, with villus height:crypt depth ratios consistently below 4:1. Viremia was confirmed in 18 of 20 pigs at euthanasia. Clinical disease was severe and developed rapidly following infection with an original North American PEDV isolate, with lesions, viremia, and antigen detection possible by 12 hpi.

Couplings between swelling and shear in saturated slit nanopores: a molecular simulation study

In this article, the coupling between swelling and shear in liquid saturated slit nanopores is studied using molecular dynamics simulations on Lennard-Jones systems. First, the consistency of the simulations using thermodynamics and direct routes is validated when dealing separately with swelling and shear. Then, the coupling between swelling and shear is explored by displacing the solid walls in one direction while letting them move freely on the other. Results indicate that shear can induce swelling and vice versa because of the confined fluid phase structure. This phenomenon, which is neglected in poromechanics modeling, may be non-negligible in highly structured microporous systems, such as clays. It implies that the response to a variation in the external load can be a combination of volumetric and shear deformations, because of the fluid. Finally, we explore the behavior induced by solid walls moving at a constant velocity. Interestingly, when the wall velocity exceeds the swelling velocity, the instantaneous states of the system are no longer at equilibrium and the averaged pore width slightly increases with increasing shear rate.

Influence of confinement on thermodiffusion

This work focuses on a possible influence of a nanoporous medium on the thermodiffusion of a fluid "isotopic" mixture. To do so, we performed molecular dynamics simulations of confined Lennard-Jones binary equimolar mixtures using grand-canonical like and non-equilibrium approaches in sub- and super-critical conditions. The study was conducted in atomistic slit pore of three adsorbent natures for various widths (from 5 to 35 times the size of a molecule). The simulation results indicate that for all thermodynamic conditions and whatever the pore characteristics, the confinement has a negligible effect on the thermal diffusion factor/Soret coefficient. However, when considered separately, the mass diffusion and thermodiffusion coefficients have been found to be largely influenced by the pore characteristics. These two coefficients decrease noticeably when adsorption is stronger and pore width smaller, a behavior that is consistent with a simple hydrodynamic explanation.

Local shear viscosity of strongly inhomogeneous dense fluids: from the hard-sphere to the Lennard-Jones fluids

This work aims at providing a tractable approach to model the local shear viscosity of strongly inhomogeneous dense fluids composed of spherical molecules, in which the density variations occur on molecular distance. The proposed scheme, which relies on the local density average model, has been applied to the quasi-hard-sphere, the Week-Chandler-Andersen and the Lennard-Jones fluids. A weight function has been developed to deal with the hard-sphere fluid given the specificities of momentum exchange. To extend the approach to the smoothly repulsive potential, we have taken into account that the non-local contributions to the viscosity due to the interactions of particles separated by a given distance are temperature dependent. Then, using a simple perturbation scheme, the approach is extended to the Lennard-Jones fluids. It is shown that the viscosity profiles of inhomogeneous dense fluids deduced from this approach are consistent with those directly computed by non-equilibrium molecular dynamics simulations.

Emergence of Porcine epidemic diarrhea virus in the United States: clinical signs, lesions, and viral genomic sequences

During the 10 days commencing April 29, 2013, the Iowa State University Veterinary Diagnostic Laboratory received the first 4 of many submissions from swine farms experiencing explosive epidemics of diarrhea and vomiting affecting all ages, with 90-95% mortality in suckling pigs. Histology revealed severe atrophy of villi in all segments of the small intestines with occasional villus-epithelial syncytial cells, but testing for rotaviruses and Transmissible gastroenteritis virus (Alphacoronavirus 1) were negative. Negative-staining electron microscopy of feces revealed coronavirus-like particles and a pan-coronavirus polymerase chain reaction (PCR) designed to amplify a conserved region of the polymerase gene for all members in the family Coronaviridae produced expected 251-bp amplicons. Subsequent sequencing and analysis revealed 99.6-100% identity among the PCR amplicons from the 4 farms and 97-99% identity to the corresponding portion of the polymerase gene of Porcine epidemic diarrhea virus (PEDV) strains, with the highest identity (99%) to strains from China in 2012. Findings were corroborated at National Veterinary Services Laboratories using 2 nested S-gene and 1 nested N-gene PCR tests where the sequenced amplicons also had the highest identity with 2012 China strains. Whole genome sequence for the virus from 2 farms in 2 different states using next-generation sequencing technique was compared to PEDV sequences available in GenBank. The 2013 U.S. PEDV had 96.6-99.5% identity with all known PEDV strains and the highest identity (>99.0%) to some of the 2011-2012 Chinese strains. The nearly simultaneous outbreaks of disease, and high degree of homology (99.6-100%) between the PEDV strains from the 4 unrelated farms, suggests a common source of virus.

Comparison of testing approaches for Clostridium difficile infection at a large community hospital

Multiple diagnostic approaches are available for Clostridium difficile infection (CDI); current guidelines support two-step testing (2ST) as the preferred approach. We retrospectively evaluated the impact of switching from toxin enzyme immunoassay (EIA) to 2ST, and then to polymerase chain reaction (PCR), on CDI rates, test utilization and CDI treatment at a 900-bed tertiary care community teaching hospital. All inpatients tested for CDI between December 2008 and February 2011 were included. A positive toxin EIA or PCR was diagnostic of CDI; 2ST was performed using glutamate dehydrogenase EIA, followed by PCR if positive. Repeat tests within 8 weeks on the same patient were considered part of the same testing episode. Data were collected electronically and studied in aggregate from 9725 unique inpatients tested for CDI, representing 20 836 individual tests. PCR detected 41% more patients with CDI than toxin EIA (p <0.0001), and 15% more than 2ST (p 0.02), corresponding to higher hospital-onset and community-onset CDI rates. The number of CDI tests performed per patient decreased by 48% with PCR (p <0.0001) compared with toxin EIA. For patients with CDI, time to the first positive test result was shortest with PCR. For patients without CDI, a negative PCR, but not 2ST, was associated with 22% fewer CDI treatment days, compared with toxin EIA (p <0.0001). Compared with both toxin EIA and 2ST, PCR detected more CDI patients faster and with less frequent testing, and negative PCR results were associated with less empirical CDI treatment.

Evaluation of diagnostic assays for the serological detection of Actinobacillus pleuropneumoniae on samples of known or unknown exposure

Accurate diagnosis of exposure to Actinobacillus pleuropneumoniae is important for maintaining negative farms. In the present study, the ability of a dual-plate complement fixation (CF) assay and 3 commercially available enzyme-linked immunosorbent assays (ELISAs; quad-plate ELISA-1, single-plate ELISA-2, and single-plate ELISA-3) in detecting serological evidence of A. pleuropneumoniae exposure was compared using serum samples of experimentally infected or vaccinated pigs, or field samples from the United States. Forty-two pigs were divided into groups of 2 pigs and were inoculated with 1 of 15 A. pleuropneumoniae strains representing all known serovars of A. pleuropneumoniae, or with Actinobacillus suis, or were vaccinated with a bacterin containing A. pleuropneumoniae serovar 1, 3, 5, or 7. Serum samples collected at the day of inoculation or vaccination and 7, 14, 21, and 28 days later were used to compare the assays. On samples from experimentally infected pigs, the dual-plate CF assay, quad-plate ELISA-1, single-plate ELISA-2, and single-plate ELISA-3 had sensitivities of 0.46, 0.74, 0.13, and 0.13 and specificities of 0.90, 1.0, 1.0, and 1.0, respectively. Vaccinated pigs were identified only by the dual-plate CF assay and the quad-plate ELISA-1. In addition, 90 serum samples with unknown A. pleuropneumoniae exposure collected under field conditions were tested with all assays. The agreement of the 4 assays on field samples was slight to fair. While several assays are available for demonstration of A. pleuropneumoniae exposure, differences in assay targets complicate test choices. Decisions on which assay or combination of assays to use depend on the specific reasons for running the assays.

Food residue recycling by swine breeders in a developing economy: a case study in Da Nang, Viet Nam

This study provides a detailed description of food residue collection by swine breeders in Da Nang, Viet Nam. In January 2011, the study surveyed 30 swine breeders in two villages with respect to locations, methods, prices, quantities, and prospects for food residue collection. The sampled swine breeders regularly visited 55 locations in central Da Nang to collect raw food residue. They then transferred the food residue to their piggeries, boiled it, and fed it to their swine. A regression analysis revealed that the total amount of food residue collected by a farm depends on the number of swine in the farm and the number of collections made per day. Swine breeders in Da Nang were estimated to collect 26.3 metric tons of organic waste per day, which amounted to 4.1% of domestic waste collected by the local government. Among the sampled swine breeders, 93% answered that they would continue using food residue for the next five years.

Local viscosity of a fluid confined in a narrow pore

In this paper, molecular dynamics simulations of a simple Lennard-Jones fluid confined in narrow slit pores and undergoing shear have been performed. The aim is to investigate the effects of density inhomogeneities at the fluid-solid interfaces on the shear viscosity profiles. It has been found that the local viscosity was varying strongly with the distance from the solid walls for both dilute and dense fluid states with oscillations correlated to the density ones. To describe the computed viscosity profiles, we propose a scheme that uses the local average density model, combined with an adequate weight function, for the configurational viscosity and a semiempirical model for the translational viscosity. It is shown that the proposed approach is able to provide viscosity profiles in good agreement with those coming from simulations for different pore widths and for different fluid states (dilute to dense).

Embedding resorcinarene cavitands in lipid vesicles()

A fluorescently labeled resorcinarene cavitand has been successfully embedded in DLPC lipid vesicles and imaged using confocal microscopy. The cavitand resides exclusively in the bilayer.

Using precipitation by polyamines as an alternative to chromatographic separation in antibody purification processes

Polyamine precipitation conditions for removing host cell protein impurities from the cell culture fluid containing monoclonal antibody were studied. We examined the impact of polyamine concentration, size, structure, cell culture fluid pH and ionic strength. A 96-well microtiter plate based high throughput screening method was developed and used for evaluating different polyamines. Polyallylamine, polyvinylamine, branched polyethyleneimine and poly(dimethylamine-co-epichlorohydrin-ethylenediamine) were identified as efficient precipitants in removing host cell protein impurities. Leveraging from the screening results, we incorporated a polyamine precipitation step into a monoclonal antibody purification process to replace the Protein A chromatography step. The optimization of the overall purification process was performed by taking the mechanisms of both precipitation and chromatographic separation into account. The precipitation-containing process removed a similar amount of process-related impurities, including host cell proteins, DNA, insulin and gentamicin and maintained similar product quality in respect of size and charge variants to chromatography based purification. Overall recovery yield was comparable to the typical Protein A affinity chromatography based antibody purification process.