A method for measuring the bioaccessibility of polycyclic aromatic hydrocarbons in cell culture media

Airborne polycyclic aromatic hydrocarbons (PAHs) and their derivatives are of particular concern for population health due to their abundance and toxicity via inhalation. Lung toxicity testing includes exposing lung epithelial cell lines to PAHs in a culture medium containing inorganic species, lipids, proteins, and other biochemicals where the cell response is influenced among others by the toxic chemical accessibility in the medium. While inhalation bioaccessibility of PAHs and other toxicants was previously studied in surrogate lung fluids, studies measuring bioaccessibility in cell culture media are rare. In this work, a method was developed to characterize PAH bioaccessibility in a culture medium used for mouse lung epithelial (FE1) cells. Further, the optimised method was tested using commercially available standard reference material of urban particulate matter (PM) as well as polyurethane foam passive air samplers (PUF-PAS). The method provided a high precision and recovery of analytes, indicating no losses during sample processing and analysis. PAHs had non-linear concentration-responses, with the culture medium approaching saturation with PM concentration of 500 μg mL-1. The results showed that phenanthrene, a 3-ring PAH, was significantly more bioaccessible than ≥4-ring congeners in the culture medium (up to ∼2.5 folds; p < 0.05). Finally, using pre-deployed PUF-PAS from a residential and an industrial site, five PAHs were found in the culture medium, including naphthalene, phenanthrene, anthracene, fluoranthene, and pyrene. This work provides a proof of concept to enable future studies to assess the inhalation bioaccessibility of polycyclic aromatic compounds and other airborne pollutants collected using PUF-PAS.

Characterizing the Movement of Per- and Polyfluoroalkyl Substances in an Avian Aquatic-Terrestrial Food Web

The movement of per- and polyfluoroalkyl substances (PFAS) through linked aquatic-terrestrial food webs is not well understood. Tree swallows (Tachycineta bicolor) in such systems may be exposed to PFAS from multiple abiotic and/or biotic compartments. We show from fatty acid signatures and carbon stable isotopes that tree swallow nestlings in southwestern Ontario fed on both terrestrial and aquatic macroinvertebrates. The PFAS profiles of air, terrestrial invertebrates, and swallows were dominated by perfluorooctanesulfonic acid (PFOS). Short-chain perfluoroalkyl acids (PFAAs) were largely restricted to air, surface water, and sediment, and long-chain PFAAs were mainly found in aquatic invertebrates and tree swallows. PFOS, multiple long-chain perfluorocarboxylic acids [perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorotridecanoic acid (PFTrDA)] and perfluorooctane sulfonamide precursors were estimated to bioaccumulate from air to tree swallows. PFOS bioaccumulated from air to terrestrial invertebrates, and PFOS, PFDA, and perfluorooctane sulfonamidoacetic acids (FOSAAs) bioaccumulated from water to aquatic invertebrates. PFOS showed biomagnification from both terrestrial and aquatic invertebrates to tree swallows, and PFDA and FOSAAs were also biomagnified from aquatic invertebrates to tree swallows. The movement of PFAS through aquatic-terrestrial food webs appears congener- and compartment-specific, challenging the understanding of PFAS exposure routes for multiple species involved in these food webs.

Trace Metals in Global Air: First Results from the GAPS and GAPS Megacities Networks

Trace metals, as constituents of ambient air, can have impacts on human and environmental health. The Global Atmospheric Passive Sampling (GAPS) and GAPS Megacities (GAPS-MC) networks investigated trace metals in the air at 51 global locations by deploying polyurethane foam disk passive air samplers (PUF-PAS) for periods of 3-12 months. Aluminum and iron exhibited the highest concentrations in air (x̅ = 3400 and 4630 ng/m3, respectively), with notably elevated values at a rural site in Argentina thought to be impacted by resuspended soil. Urban sites had the highest levels of toxic Pb and Cd, with enrichment factors suggesting primarily anthropogenic influences. High levels of As at rural sites were also observed. Elevated trace metal concentrations in cities are associated with local emissions and higher PM2.5 and PM10 concentrations. Brake and tire wear-associated metals Sb, Cu, and Zn are significantly correlated and elevated at urban locations relative to those at background sites. These data demonstrate the versatility of PUF-PAS for measuring trace metals and other particle-associated pollutants in ambient air in a cost-effective and simple manner. The data presented here will serve as a global baseline for assessing future changes in ambient air associated with industrialization, urbanization, and population growth.

THE ROLE OF EXERCISE IN PREVENTING CHRONIC DISEASES: CURRENT EVIDENCE AND RECOMMENDATIONS

Regular exercise helps to enhance health outcomes and lower risk factors, making it a crucial element in the prevention of chronic diseases. By being physically active, people can improve their general health and delay the onset of a number of chronic illnesses. For understanding the relationship between increased physical activity or decreased physical inactivity and favorable health outcomes, observational studies are the main source of information. We will look for systematic analyses of randomized controlled trials with a main emphasis on outcomes linked to diseases in the Cochrane Database of systematic studies. Evaluation will be limited to those in a few key chronic conditions. Preventing chronic illness and achieving better results in the management or treatment of chronic illness are the main outcomes of interest. For each chronic condition (such as the control of glucose in diabetes or any change in hypertension blood pressure), these results will be summarized and displayed. The design and implementation of chronic conditions, physical exercise illness conditions, and adverse physical activity-related events are of secondary interest. Our findings should help decision-makers, guideline organizations, and academics identify the most effective physical activity programs for major chronic disease management and prevention. Exercise and physical activity (PA) offers a non-invasive approach to the management of chronic disorders. More physiological, biochemical, and molecular data on the positive effects of PA and exercise on health should constitute a primary focus of future studies.

Per- and polyfluoroalkyl substances and volatile methyl siloxanes in global air: Spatial and temporal trends

The study reports on the atmospheric concentrations of per- and polyfluoroalkyl substances (PFAS) and volatile methyl siloxanes (VMS) measured using sorbent-impregnated polyurethane foam disks (SIPs) passive air samplers. New results are reported for samples collected in 2017, which extends temporal trend information to the period 2009-2017, for 21 sites where SIPs have been deployed since 2009. Among neutral PFAS, fluorotelomer alcohols (FTOHs) had higher concentrations than perfluoroalkane sulfonamides (FOSAs) and perfluoroalkane sulfonamido ethanols (FOSEs) with levels of ND‒228, ND‒15.8, ND‒10.4 pg/m³, respectively. Among ionizable PFAS, the sum of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) in air were 0.128-781 and 6.85-124 pg/m³, respectively. Longer-chain i.e. C₉-C₁₄ PFAS, which are relevant to the recent proposal by Canada for a listing of long-chain (C₉-C₂₁) PFCAs to the Stockholm Convention, were also detected in the environment at all site categories including Arctic sites. Cyclic and linear VMS ranged between 1.34‒452 and 0.01-12.1 ng/m³, respectively, showing dominance in urban areas. Despite the wide range of levels observed across different site categories, geometric means of the PFAS and VMS groups were fairly similar when grouped according to the five United Nations regions. Variable temporal trends in air (2009-2017) were observed for both PFAS and VMS. PFOS, which has been listed in the Stockholm Convention since 2009, is still showing increasing tendencies at several sites, indicating constant input from direct and/or indirect sources. These new data inform international chemicals management for PFAS and VMS.

Air monitoring of tire-derived chemicals in global megacities using passive samplers

Pollution from vehicle tires has received world-wide research attention due to its ubiquity and toxicity. In this study, we measured various tire-derived contaminants semi-quantitatively in archived extracts of passive air samplers deployed in 18 major cities that comprise the Global Atmospheric Passive Sampling (GAPS) Network (GAPS-Megacities). Analysis was done on archived samples, which represent one-time weighted passive air samples from each of the 18 monitoring sites. The target analytes included cyclic amines, benzotriazoles, benzothiazoles, and p-phenylenediamine (PPD) derivatives. Of the analyzed tire-derived contaminants, diphenylguanidine was the most frequently detected analyte across the globe, with estimated concentrations ranging from 45.0 pg/m3 in Beijing, China to 199 pg/m3 in Kolkata, India. The estimated concentrations of 6PPD-quinone and total benzothiazoles (including benzothiazole, 2-methylthio-benzothiazole, 2-methyl-benzothiazole, 2-hydroxy-benzothiazole) peaked in the Latin American and the Caribbean region at 1 pg/m3 and 100 pg/m3, respectively. In addition, other known tire-derived compounds, such as hexa(methoxymethyl)melamine, phenylguanidine, and various transformation products of 6PPD, were also monitored and characterized semi-quantitatively or qualitatively. This study presents some of the earliest data on airborne concentrations of chemicals associated with tire-wear and shows that passive sampling is a viable techniquefor monitoring airborne tire-wear contamination. Due to the presence of many tire-derived contaminants in urban air across the globe as highlighted by this study, there is a need to determine the associated exposure and toxicity of these chemicals to humans.

Medium- and long-chain chlorinated paraffins in air: A review of levels, physicochemical properties, and analytical considerations

Chlorinated paraffins (CPs) are synthetic chemicals that are produced at high volumes and have a global presence. CPs are generally divided into three groups based on their carbon chain lengths: short-chain CPs (SCCPs, C_10-13), medium-chain CPs (MCCPs, C_14-17), and long-chain CPs (LCCPs, C_≥18). SCCPs have been formally recognized as persistent organic pollutants (POPs) and have been listed under the Stockholm Convention on POPs. Concerns about increases in MCCP and LCCP production as replacements for SCCP products are rising, given their similar properties to SCCPs and the fact that they remain relatively understudied with only a few reported measurements in air. Passive air samplers with polyurethane foam disks (PUF-PAS), which have been successfully applied to SCCPs, provide an opportunity to expand the existing body of data on MCCP and LCCP air concentrations, as they are inexpensive and require little maintenance. The uptake of MCCPs and LCCPs by PUF disk samplers is characterized in this paper based on newly derived PUF-air partitioning coefficients using COSMOtherm. The ability of PUF disk samplers to capture both gas-phase and particle fractions is important because MCCPs and LCCPs have reduced volatility compared to SCCPs and therefore are mainly associated with particulate matter in air. In addition, due to their use as additives in plastics and rubber products, they are associated with micro- and nanoplastics, which are considered to be potential vectors for the long-range atmospheric transport (LRAT) of these chemicals. The review has highlighted other limitations to reporting of MCCPs and LCCPs in air, including the lack of suitable analytical standards and the requirement for advanced analytical methods to detect and resolve these complex mixtures. Overall, this review indicates that further research is needed in many areas for medium- and long-chain chlorinated paraffins in order to better understand their occurrence, transport and fate in air.

Implication and utility of DAS-28 squeeze in rheumatoid arthritis: an Indian experience

The purpose of this study was to compare and correlate disease activity score including 28 joints counts (DAS-28) Squeeze with DAS-28 and clinical disease activity index (CDAI) to assess disease activity (DA) in rheumatoid arthritis (RA) patients. A total of 100 RA patients were included in the study. All subjects were evaluated for disease activity using the DAS-28 Squeeze, DAS-28, and CDAI. Spearman’s rho (ρ) was calculated to determine the correlation between DAS-28 Squeeze, DAS-28, and CDAI. Cross-tabulation was performed to compare and calculate the kappa coefficient for the link between two indices. For each scale, Cronbach’s alpha was also calculated to test dependability. The average age of the study group was 43.9±11.3. The mean scores on the DAS-28 Squeeze, DAS-28, and CDAI were, respectively, 3.58±1.06, 5.06±1.56, and 22.81±14.92. p=0.001 indicated a significant correlation between DAS-28 Squeeze and DAS-28 (ρ=0.986) and CDAI (ρ=0.939) for DAS-28 Squeeze. There was a considerable correlation between all three measures at various DA levels. Cronbach’s alpha for DAS-28 Squeeze, DAS-28, and CDAI were respectively 0.716, 0.663, and 0.734. DAS-28 Squeeze exhibited a substantial positive association with DAS-28 and CDAI for assessing disease activity and appears to be a more useful and reliable method than DAS-28 and CDAI for monitoring disease activity in RA patients.

Patient reported outcomes after risk-reducing surgery in patients at increased risk of ovarian cancer

OBJECTIVE

To describe the quality of life of women at an increased risk of ovarian cancer undergoing risk-reducing bilateral salpingo-oophorectomy (RRBSO).

METHODS

Patients evaluated in our gynecologic oncology ambulatory practice between January 2018-December 2019 for an increased risk of ovarian cancer were included. Patients received the EORTC QLQ-C30 and PROMIS emotional and instrumental support questionnaires along with a disease-specific measure (PROM). First and last and pre- and post-surgical PROM responses in each group were compared as were PROMs between at-risk patients and patients with other ovarian diseases.

RESULTS

195 patients with an increased risk of ovarian cancer were identified, 155 completed PROMs (79.5%). BRCA1 or BRCA2 mutations were noted in 52.8%. Also included were 469 patients with benign ovarian disease and 455 with ovarian neoplasms. Seventy-two at-risk patients (46.5%) had surgery and 36 had both pre- and post-operative PROMs. Post-operatively, these patients reported significantly less tension (p = 0.011) and health-related worry (p = 0.021) but also decreased levels of health (p = 0.018) and quality of life <7d (0.001), less interest in sex (p = 0.014) and feeling less physically attractive (p = 0.046). No differences in body image or physical/sexual health were noted in at-risk patients who did not have surgery. When compared to patients with ovarian neoplasms, at-risk patients reported lower levels of disease-related life interference and treatment burden, less worry, and better overall health.

CONCLUSIONS

In patients with an increased risk of ovarian cancer, RRBSO is associated with decreased health-related worry and tension, increased sexual dysfunction and poorer short-term quality of life. Patients with ovarian neoplasms suffer to a greater extent than at-risk patients and report higher levels of treatment burden and disease-related anxiety.

Toxicity screening of air extracts representing different source sectors in the Greater Toronto and Hamilton areas: In vitro oxidative stress, pro-inflammatory response, and toxicogenomic analysis

In the present study, the suitability and sensitivity of different in vitro toxicity endpoints were determined to evaluate and distinguish the specific contributions of polycyclic aromatic carbon (PAC) mixtures from various sites in Toronto (Canada), to pulmonary toxicity. Air samples were collected for two-month periods from April 2014 to March 2015 from one location, and from August 2016 to August 2017 from multiple locations reflecting different geographical areas in Toronto, and the Greater Toronto Area, with varying source emissions including background, traffic, urban, industrial and residential sites. Relative concentrations of PACs and their derivatives in these air samples were characterised. In vitro cytotoxicity, pro-inflammatory, and oxidative stress assays were employed to assess the acute pulmonary effects of urban-air-derived air pollutants. In addition, global transcriptional profiling was utilized to understand how these chemical mixtures exert their harmful effects. Lastly, the transcriptomic data and the chemical profiles for each site and season were used to relate the biological response back to individual constituents. Site-specific responses could not be derived; however, the Spring season was identified as the most responsive through benchmark concentration analysis. A combination of correlational analysis and principal component analysis revealed that nitrated and oxygenated polycyclic aromatic hydrocarbons (PAHs) drive the response at lower concentrations while specific PAHs drive the response at the highest concentration tested. Unsubstituted PAHs are the current targets for analysis as priority pollutants. The present study highlights the importance of by-products of PAH degradation in the assessment of risk. The study also demonstrates the usefulness of in vitro toxicity assays to derive meaningful data in support of risk assessment.

Cytotoxic and Transcriptomic Effects in Avian Hepatocytes Exposed to a Complex Mixture from Air Samples, and Their Relation to the Organic Flame Retardant Signature

Assessing complex environmental mixtures and their effects is challenging. In this study, we evaluate the utility of an avian in vitro screening approach to determine the effects of passive air sampler extracts collected from different global megacities on cytotoxicity and gene expression. Concentrations of a suite of organic flame retardants (OFRs) were quantified in extracts from a total of 19 megacities/major cities in an earlier study, and levels were highly variable across sites. Chicken embryonic hepatocytes were exposed to serial dilutions of extracts from the 19 cities for 24 h. Cell viability results indicate a high level of variability in cytotoxicity, with extracts from Toronto, Canada, having the lowest LC50 value. Partial least squares (PLS) regression analysis was used to estimate LC50 values from OFR concentrations. PLS modeling of OFRs was moderately predictive of LC50 (p-value = 0.0003, r² = 0.66, slope = 0.76, when comparing predicted LC50 to actual values), although only after one outlier city was removed from the analysis. A chicken ToxChip PCR array, comprising 43 target genes, was used to determine effects on gene expression, and similar to results for cell viability, gene expression profiles were highly variable among the megacities. PLS modeling was used to determine if gene expression was related to the OFR profiles of the extracts. Weak relationships to the ToxChip expression profiles could be detected for only three of the 35 OFRs (indicated by regression slopes between 0.6 and 0.5 when comparing predicted to actual OFR concentrations). While this in vitro approach shows promise in terms of evaluating effects of complex mixtures, we also identified several limitations that, if addressed in future studies, might improve its performance.

FMS (Federated Model as a service) for healthcare: an automated secure-framework for personalized recommendation system

The Healthcare sector has been emerging on the platform ofdata science. And data scientists are often using machine learningtechniques based on historical data to create models, makepredictions or recommendations. This paper aims to providebackground and information for the community on the benefitsand variants of Federated Learning (F.L.) with other technologiesfor medical applications and highlight key considerationsand challenges of F.L. implementation in the digital health background.With this FMaaS, we envisage a future for digital federatedhealth. We hope to empower and raise awareness aboutthe environment and fog computing to provide a more secureand better-analyzing environment. The AutoML framework isused to generate and optimize machine learning models usingautomatic engineering tools, model selection, and hyperparameteroptimization on fog nodes. Thus, making the systemmore reliable and secure for each individual by preserving privacyat their end devices. And this will lead to a personalizedrecommendation system for each individual associated withthis framework by deploying the Model to their devices foron-device inferences through the concept of differential privateModel averaging. With this framework, users don’t haveto compromise with privacy, and all their sensitive data will besecure on their end devices.

Fugacity-Based Trophic Magnification Factors Characterize Bioaccumulation of Cyclic Methyl Siloxanes within an Urban Terrestrial Avian Food Web: Importance of Organism Body Temperature and Composition

Trophic magnification of cyclic volatile methyl siloxanes (cVMS) in a terrestrial food web was investigated by measuring concentrations of octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) and two reference chemicals within air and biota samples from an avian food web located in a mixed urban-agricultural landscape. Terrestrial trophic magnification factors derived from lipid normalized concentrations (TMF_Ls) for D5 and D6 were 0.94 (0.17 SE) and 1.1 (0.23 SE) and not statistically different from 1 (p > 0.05); however, the TMF_L of D4 was 0.62 (0.11 SE) and statistically less than 1 (p < 0.001). TMF_Ls of PCB-153 and p,p'-DDE were 5.6 (2.2 SE) and 6.1 (2.8 SE) and statistically greater than 1 (p < 0.001). TMF_Ls of cVMS in this terrestrial system were similar to those reported in aquatic systems. However, trophic magnification factors derived on a fugacity basis (TMF_Fs), which recognize differences in body temperature and lipid composition between organisms, were greater than corresponding TMF_Ls primarily because a temperature-induced thermodynamic biomagnification of hydrophobic chemicals occurs when endothermic organisms consume poikilothermic organisms. Therefore, we recommend that biomagnification studies of food webs including endothermic and poikilothermic organisms incorporate differences in body temperature and tissue composition to accurately characterize the biomagnification potential of chemicals.

Guidance on the Application of Polyurethane Foam Disk Passive Air Samplers for Measuring Nonane and Short-Chain Chlorinated Paraffins in Air: Results from a Screening Study in Urban Air

This study provides guidance on using polyurethane foam-based passive air samplers (PUF-PASs) for atmospheric nonane chlorinated paraffins (C₉-CPs) and short-chain CPs (SCCPs) and reports SCCP concentrations in air in the Greater Toronto Area (GTA), Canada. We estimated the partition coefficients between PUF and air (K_PUF-A) and between octanol and air (K_OA) for C₉-CP and SCCP congeners using the COSMO-RS method, so that PUF disk uptake profiles for each formula group could be calculated. We then measured SCCP concentrations in PUF disk samples collected from distinct source sectors in urban air across the GTA. Concentrations in samplers were used to calculate C₉-CP and SCCP concentrations in air and the PUF disk uptake profiles revealed that time-weighted linear phase sampling was possible for congeners having log K_OA values greater than 8.5. The highest SCCP concentrations, with an annual average concentration of 35.3 ng/m³, were measured at the industrial site, whereas lower but comparable SCCP concentrations were found in residential and background sites, with annual averages of 7.73 and 10.5 ng/m³, respectively. No consistent seasonal variation in SCCP concentrations was found in the six distinct source sectors. Direct measurements of K_PUF-A and K_OA values as a function of temperature could be used to increase accuracy in future studies.

Characterization of Opalescence in low Volume Monoclonal Antibody Solutions Enabled by Microscale Nephelometry

Monoclonal antibody (mAb)-based drugs are often prone to unfavorable solution behaviors including high viscosity, opalescence, phase separation, and aggregation at the high concentrations needed to enable patient-centric subcutaneous dosage forms. Given that these can have a detrimental impact on manufacturability, stability, and delivery, approaches to identifying, monitoring, and controlling these behaviors during drug development are critical. Opalescence presents a significant challenge due to its relationship to liquid-liquid phase separation. Quantitative characterization of opalescence via turbidimetry is often restrictive due to large volume requirements (>2 mL) and alternative microscale approaches based on light transmittance (Eckhardt et al., J Pharm Sci Technol. 1994, 48: 64-70) may pose challenging with respect to accuracy. To address the need for accurate and quantitative microscale opalescence measurements, we have evaluated the use of a 'de-tuned' static light scattering detector which requires <10 μL sample per measurement. We show that tuning of the laser power to a range far below that of traditional light scattering measurements results in a stable detector response that can be accurately calibrated to the nephelometric turbidity unit (NTU) scale using appropriate standards. The calibrated detector signal yields NTU values for mAbs and other protein solutions that are comparable to a commercial turbidimeter. We used this microscale approach to characterize the opalescence of 48 commercial mAb drug products and found that the majority have opalescence below 15 NTU. However, in products with mAb concentrations greater than 75 mg/mL, a broad range of opalescence was observed, in a few cases greater than 20 NTU. These measurements as well as nephelometric characterization of several IgG1 and IgG4 mAbs across a broad pH range highlight subclass-specific tendencies toward opalescence in high concentration solutions.

Suicide, self-harm and thoughts of suicide or self-harm in infectious disease epidemics: a systematic review and meta-analysis

AIMS

Suicide accounts for 2.2% of all years of life lost worldwide. We aimed to establish whether infectious epidemics are associated with any changes in the incidence of suicide or the period prevalence of self-harm, or thoughts of suicide or self-harm, with a secondary objective of establishing the frequency of these outcomes.

METHODS

In this systematic review and meta-analysis, MEDLINE, Embase, PsycINFO and AMED were searched from inception to 9 September 2020. Studies of infectious epidemics reporting outcomes of (a) death by suicide, (b) self-harm or (c) thoughts of suicide or self-harm were identified. A random-effects model meta-analysis for the period prevalence of thoughts of suicide or self-harm was conducted.

RESULTS

In total, 1354 studies were screened with 57 meeting eligibility criteria, of which 7 described death by suicide, 9 by self-harm, and 45 thoughts of suicide or self-harm. The observation period ranged from 1910 to 2020 and included epidemics of Spanish Flu, severe acute respiratory syndrome, human monkeypox, Ebola virus disease and coronavirus disease 2019 (COVID-19). Regarding death by suicide, data with a clear longitudinal comparison group were available for only two epidemics: SARS in Hong Kong, finding an increase in suicides among the elderly, and COVID-19 in Japan, finding no change in suicides among children and adolescents. In terms of self-harm, five studies examined emergency department attendances in epidemic and non-epidemic periods, of which four found no difference and one showed a reduction during the epidemic. In studies of thoughts of suicide or self-harm, one large survey showed a substantial increase in period prevalence compared to non-epidemic periods, but smaller studies showed no difference. As a secondary objective, a meta-analysis of thoughts of suicide and self-harm found that the pooled prevalence was 8.0% overall (95% confidence interval (CI) 5.2-12.0%; 14 820 of 99 238 cases in 24 studies) over a time period of between seven days and six months. The quality assessment found 42 studies were of high quality, nine of moderate quality and six of high quality.

CONCLUSIONS

There is little robust evidence on the association of infectious epidemics with suicide, self-harm and thoughts of suicide or self-harm. There was an increase in suicides among the elderly in Hong Kong during SARS and no change in suicides among young people in Japan during COVID-19, but it is unclear how far these findings may be generalised. The development of up-to-date self-harm and suicide statistics to monitor the effect of the current pandemic is an urgent priority.

Effect of surgical approach on risk of recurrence after vaginal brachytherapy in early-stage high-intermediate risk endometrial cancer

OBJECTIVE

The objective was to determine if surgical approach affects time to recurrence in early-stage high-intermediate risk endometrial cancer (HIR-EC) treated with adjuvant vaginal brachytherapy (VBT).

METHODS

In this retrospective cohort study, HIR-EC patients treated with VBT between 2005 and 2017 were identified and those who received open or minimally invasive hysterectomies (MIS) were included. Clinical and surgical variables were analyzed and time to recurrence was compared between surgical groups.

RESULTS

We identified 494 patients, of which 363 had MIS hysterectomies, 92.5% had endometrioid histology, 45.7% were stage IA and 48.0% stage IB. Open hysterectomy patients had higher BMIs (p = 0.007), lower rates of lymph node sampling (p < 0.001) and lymphovascular space invasion (LVSI) (p = 0.036), however in patients who recurred, no differences were noted between groups. Overall, 65 patients (13.2%) recurred, 14 in the open group (10.7%) and 51 in the MIS group (14.0%) (p = 0.58), while vaginal recurrences were noted in 4.6% and 6.1% respectively. When compared to the open group, the MIS group had a significantly shorter time to any recurrence (p = 0.022), to pelvic (p = 0.05) and locoregional recurrence (p = 0.021) and to death from any cause (p = 0.039). After adjusting for age, BMI, grade, LVSI and surgery date, the MIS group had a higher risk of any recurrence (HR 2.29 (1.07-4.92), p = 0.034) and locoregional recurrence (HR 4.18 (1.44-12.1), p = 0.008).

CONCLUSIONS

Patients with HIR-EC treated with VBT after MIS hysterectomy have a shorter time to recurrence and higher risk of recurrence when compared to open hysterectomy patients. Further studies into the safety of MIS in high-intermediate risk patients are required.

GAPS-megacities: A new global platform for investigating persistent organic pollutants and chemicals of emerging concern in urban air

A pilot study was initiated in 2018 under the Global Atmospheric Passive Sampling (GAPS) Network named GAPS-Megacities. This study included 20 megacities/major cities across the globe with the goal of better understanding and comparing ambient air levels of persistent organic pollutants and other chemicals of emerging concern, to which humans residing in large cities are exposed. The first results from the initial period of sampling are reported for 19 cities for several classes of flame retardants (FRs) including organophosphate esters (OPEs), polybrominated diphenyl ethers (PBDEs), and halogenated flame retardants (HFRs) including new flame retardants (NFRs), tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCDD). The two cities, New York (USA) and London (UK) stood out with ∼3.5 to 30 times higher total FR concentrations as compared to other major cities, with total concentrations of OPEs of 15,100 and 14,100 pg/m³, respectively. Atmospheric concentrations of OPEs significantly dominated the FR profile at all sites, with total concentrations in air that were 2-5 orders of magnitude higher compared to other targeted chemical classes. A moderately strong and significant correlation (r = 0.625, p < 0.001) was observed for Gross Domestic Product index of the cities with total OPEs levels. Although large differences in FR levels were observed between some cities, when averaged across the five United Nations regions, the FR classes were more evenly distributed and varied by less than a factor of five. Results for Toronto, which is a 'reference city' for this study, agreed well with a more in-depth investigation of the level of FRs over different seasons and across eight sites representing different urban source sectors (e.g. traffic, industrial, residential and background). Future sampling periods under this project will investigate trace metals and other contaminant classes, linkages to toxicology, non-targeted analysis, and eventually temporal trends. The study provides a unique urban platform for evaluating global exposome.

A single molecular descriptor to predict solution behavior of therapeutic antibodies

Despite the therapeutic success of monoclonal antibodies (mAbs), early identification of developable mAb drug candidates with optimal manufacturability, stability, and delivery attributes remains elusive. Poor solution behavior, which manifests as high solution viscosity or opalescence, profoundly affects the developability of mAb drugs. Using a diverse dataset of 59 mAbs, including 43 approved products, and an array of molecular descriptors spanning colloidal, conformational, charge-based, hydrodynamic, and hydrophobic properties, we show that poor solution behavior is prevalent (>30%) in mAbs and is singularly predicted (>90%) by the diffusion interaction parameter (k _D), a dilute-solution measure of colloidal self-interaction. No other descriptor, individually or in combination, was found to be as effective as k _D. We also show that well-behaved mAbs, a substantial subset of which bear high positive charge and pI, present no disadvantages with respect to pharmacokinetics in humans. Here, we provide a systematic framework with quantitative thresholds for selecting well-behaved therapeutic mAbs during drug discovery.

Measurements of a 2.1 MeV H- beam with an Allison scanner

Transverse 2D phase space distributions of a 2.1 MeV, 5 mA H^- beam are measured at the Proton Improvement Plan II Injector Test accelerator at Fermilab with an Allison scanner. This paper describes the design, calibration, and performance of the scanner along with the main results from beam measurements. Analyses of the recorded phase portraits are performed primarily in action-phase coordinates. The stability of the action under linear optics makes it easier to compare measurements taken under different beamline conditions. The amplitude of a single measured point ("pixel") is proportional to the phase density in the corresponding portion of the beam. When the Twiss parameters are calculated using only the high-phase density part of the beam, the pixel amplitude in the beam core is found to be decreasing approximately exponentially with action and to be phase-independent. Outside of the core, the amplitudes decrease with action at a slower rate than in the core. This "tail" comprises 10%-30% of the beam, with 0.1% of the total measured intensity extending beyond action 10-20 times larger than the rms emittance. The transition from the core to the tail is accompanied by the appearance of two "branches" that are separated in phase and extend beyond the core. A set of selected measurements shows that there is no measurable emittance dilution along the beamline; the beam parameters are practically constant over a 0.5 ms pulse; and scraping in various parts of the beamline is an effective way to decrease the transverse tails by removing the branches.

Oocyte and embryo evaluation by AI and multi-spectral auto-fluorescence imaging: Livestock embryology needs to catch-up to clinical practice

A highly accurate 'non-invasive quantitative embryo assessment for pregnancy' (NQEAP) technique that determines embryo quality has been an elusive goal. If developed, NQEAP would transform the selection of embryos from both Multiple Ovulation and Embryo Transfer (MOET), and even more so, in vitro produced (IVP) embryos for livestock breeding. The area where this concept is already having impact is in the field of clinical embryology, where great strides have been taken in the application of morphokinetics and artificial intelligence (AI); while both are already in practice, rigorous and robust evidence of efficacy is still required. Even the translation of advances in the qualitative scoring of human IVF embryos have yet to be translated to the livestock IVP industry, which remains dependent on the MOET-standardised 3-point scoring system. Furthermore, there are new ways to interrogate the biochemistry of individual embryonic cells by using new, light-based methodologies, such as FLIM and hyperspectral microscopy. Combinations of these technologies, in particular combining new imaging systems with AI, will lead to very accurate NQEAP predictive tools, improving embryo selection and recipient pregnancy success.

Experimental Study of OH-Initiated Heterogeneous Oxidation of Organophosphate Flame Retardants: Kinetics, Mechanism, and Toxicity

The environmental risks and health impacts associated with particulate organophosphate flame retardants (OPFRs), which are ubiquitous in the global atmosphere, have not been adequately assessed due to the lack of data on the reaction kinetics, products, and toxicity associated with their atmospheric transformations. Here, the importance of such transformations for OPFRs are explored by investigating the reaction kinetics, degradation chemical mechanisms, and toxicological evolution of two OPFRs (2-ethylhexyl diphenyl phosphate (EHDP) and diphenyl phosphate (DPhP)) coated on (NH₄)₂SO₄ particles upon heterogeneous OH oxidation. The derived reaction rate constants for the heterogeneous loss of EHDP and DPhP are (1.12 ± 0.22) × 10^-12 and (2.33 ± 0.14) × 10^-12 cm³ molecules^-1 s^-1, respectively. Using recently developed real-time particle chemical composition measurements, particulate products from heterogeneous photooxidation and the associated degradation mechanisms for particulate OPFRs are reported for the first time. Subsequent cytotoxicity analysis of the unreacted and oxidized OPFR particles indicated that the overall particle cytotoxicity was reduced by up to 94% with heterogeneous photooxidation, likely due to a significantly lower cytotoxicity associated with the oxidized OPFR products relative to the parent OPFRs. The present work not only provides guidance for future field sampling for the detection of transformation products of OPFRs, but also strongly supports the ongoing risk assessment of these emerging chemicals and most critically, their products.

Pre-surgical lung biopsy in management of solitary pulmonary nodules: a cost effectiveness analysis

Objectives: Tissue diagnosis prior to thoracic surgery with curative intent is vital in thoracic lesions concerning for lung cancer. Methods of obtaining tissue diagnosis are variable within the United Kingdom.Methods: We performed a model-based analysis to identify the most efficient method of diagnosis using both a health care perspective. Our analysis concerns adults in the UK presenting with a solitary pulmonary nodule suspicious for a primary lung malignancy, patients with more advanced disease (for example lymph node spread) were not considered. Model assumptions were derived from published sources and expert reviews, cost data were obtained from healthcare research group cost estimates (2016-17). Outcomes were measured in terms of costs experienced to healthcare trusts.Results: Our results show that CT guided percutaneous lung biopsy using an ambulatory approach, is the most cost-effective method of diagnosis. Indeed, using this approach, trust experience approximately half of the cost of an approach of surgical lung biopsy performed at the time of potential resection ('frozen section').Limitations and conclusions: Whilst this analysis is limited to the specific scenario of a solitary pulmonary nodule, these findings have implications for the implementation of lung cancer screening in the UK, which is likely to result in increased numbers of patients with such early disease.

Direct measurements of polyurethane foam (PUF) ‒ air partitioning coefficients for chemicals of emerging concern capable of equilibrating in PUF disk samplers

Organophosphate esters (OPEs), novel flame retardants (NFRs) and organochlorine pesticides (OCPs) are volatile to semi-volatile chemicals and therefore susceptible to approach equilibrium during typical deployments of polyurethane foam (PUF) disk passive air samplers. A generator column approach was used to measure the PUF-air partitioning coefficient (K_PUF-air) for these targeted chemicals. K_PUF-air values are required for these chemicals to estimate sampled equivalent air volumes, which vary substantially with temperature. Log K_PUF-air measurements were made at temperatures ranging from +6 to +35 °C and resulting values ranged from 5.14 to 7.77. Enthalpies of phase change for PUF to air (ΔH_PUF-air, kJ/mol) ranged from 51.3 to 98.9. Two relationships of log K_PUF-air versus log K_octanol-air (K_OA) were derived, grouping OPEs and NFRs separately. The relationship for NFRs was in fair agreement (within about 0.6 log units) to a long-standing relationship by Shoeib and Harner (since 2002) for polychlorinated biphenyls (PCBs). However, the estimated values using Shoeib-Harner relationship substantially underestimates K_PUF-air for the OPEs than directly measured values (by about an order of magnitude). These findings highlight the importance of the direct measurements of K_PUF-air for emerging classes of chemicals whose concentrations are at risk of equilibrating in PUF disk samplers.

Secondary colonic stent insertion in acute large bowel obstruction following primary stent failure

INTRODUCTION

Colonic stent insertion has been shown to be an effective treatment for patients with acute large bowel obstruction, either as a bridge to surgery or as definitive treatment. However, little is known of the role of secondary stent insertion following primary stent failure in patients considered inappropriate or high risk for emergency surgery.

METHODS

Fourteen patients presenting with acute large bowel obstruction who had previously been treated with colonic stent insertion were studied. All underwent attempted placement of a secondary stent.

RESULTS

Technical deployment of the stent was accomplished in 12 patients (86%) but only 9 (64%) achieved clinical decompression. Successful deployment and clinical decompression of a secondary stent was associated with older age (p=0.038). Sex, pathology, site of obstruction, duration of efficacy of initial stent and cause of primary failure were unrelated to outcome. No procedure related morbidity or mortality was noted following repeated intervention.

CONCLUSIONS

Secondary colonic stent insertion appears an effective, safe treatment in the majority of patients presenting with acute large bowel obstruction following failure of a primary stent.

P696Incidence of sinus node dysfunction with cancer chemotherapy: a systematic review of literature

Background

Introduction of newer classes of chemotherapeutic agents has led to improved survival in many cancers, often at the cost of increased side effects. With the advent of cardio-oncology, there has been growing focus on cardiac side effects of chemotherapy like cardiomyopathy, QT prolongation, VT and AF. However, data on cancer chemotherapy related sinus node dysfunction (SND) is limited.

Objective

To assess the incidence of chemotherapy related SND through a systematic review of available literature.

Methods

We performed a systematic review of PUBMED database for studies reporting SND (including sinus bradycardia, sinus pauses, sinoatrial exit blocks or asystole) with use of chemotherapeutic agents. Weighted average incidence of SND was calculated from studies. Case reports were reported independently.

Results

2012 articles were reviewed of which 38 were eligible for data extraction. Incidence of SND varied significantly between drug classes. However, specific drugs were associated with increased incidence of SND like anthracyclines (Epirubicin 8.3%), antimetabolites (5 Fluorouracil 20%), tyrosine kinase inhibitors (crizotinib 43%), antimicrotubule agents (paclitaxel 29%) and angiogenesis inhibitors (Thalidomide 22%). The weighted average incidence is shown in table.

Drug type Drug Type of cancers No. of studies Total No. Weighted average of incidence of sinus arrhythmias No. of case reports Anthracyclines Epirubicin Breast, Hodgkin's disease 1 24 8.3% 1 Idarubicin CML – – – 1 Unclassified anthracyclines Ewing sarcoma 2 370 4.31% – Antimetabolites 5 Fluorouracil Esophageal, gastric, colon, rectal 1 5 20% 1 Capecitabine Rectal cancer – – – 1 Methotrexate Osteosarcoma – – – 1 Cytarabine AML – – – 1 Antimicrotubule agent Paclitaxel Ovarian cancer 2 4505 29.36% – Kinase inhibitors Crizotinib Lung 2 1095 43% 4 Alectinib Lung 1 225 5% – Ibrutinib Mantle cell lymphoma – – – 1 Monoclonal antibodies Infliximab Ulcerative colitis – – – 1 Angiogenesis inhibitors Thalidomide Multiple myeloma 4 83 21.62% 2 Endostar Metastatic colorectal and gastric 1 23 13% – Selective estrogen modulators Tamoxifene Extracranial meningioma – – – 1 Antiandrogen Abiraterone Prostate cancer 1 17 6% – Other drugs Crisnatol mesylate Advanced solid tumors 1 43 2.3% – Mitoxantrone AML – – – 1 Combination drugs Bevacizumab +Vorinostat Malignant Glioma 1 40 3% – All-trans-retinoic acid+idarubicin AML – – – 2 Tivantinib+Erlotinib Advanced solid malignancies 1 32 23.1% – Paclitaxel+Carboplatin+Bevacizumab Lung – – – 1 Paclitaxel+Carboplatin Ovarian 1 79 2.9% – Daunorubicin+Amsacrine AML – – – 1 CHOP Diffuse large B cell lymphoma – – – 1

Conclusion

There is cumulative evidence of increased incidence of SND with certain chemotherapeutics. In pre-existing SND, certain drugs and combinations must be avoided and alternative agents, should be considered. Future studies are needed to evaluate the role of remote cardiac monitoring and permanent pacing in specific situations where no safer alternatives exist.

Associations Between Age at Arterial Switch Operation, Brain Growth, and Development in Infants With Transposition of the Great Arteries

BACKGROUND

Brain injury, impaired brain growth, and long-term neurodevelopmental problems are common in children with transposition of the great arteries. We sought to identify clinical risk factors for brain injury and poor brain growth in infants with transposition of the great arteries undergoing the arterial switch operation, and to examine their relationship with neurodevelopmental outcome.

METHODS

The brains of 45 infants with transposition of the great arteries undergoing surgical repair were imaged pre- and postoperatively using magnetic resonance imaging. Brain weight z scores were calculated based on brain volume and autopsy reference data. Brain injury scores were determined as previously described. Neurodevelopment was assessed at 18 months using the Bayley-III scores of infant development. The relationships between clinical variables, brain injury, perioperative brain growth, and 18-month Bayley-III scores were analyzed.

RESULTS

On preoperative imaging, moderate or severe white matter injury was present in 10 of 45 patients, whereas stroke was seen in 4 of 45. A similar prevalence of injury was seen on postoperative imaging, and we were unable to identify any clinical risk factors for brain injury. Brain weight z scores decreased perioperatively in 35 of 45 patients. The presence of a ventricular septal defect ( P=0.009) and older age at surgery ( P=0.007) were associated with impaired perioperative brain growth. When patients were divided into those undergoing surgery during the first 2 weeks of life (32/45) versus those being repaired later (13/45), infants repaired later had significantly worse perioperative brain growth (late repair postoperative brain weight z = -1.0±0.90 versus early repair z = -0.33±0.64; P=0.008). Bayley-III testing scores fell within the normal range for all patients, although age at repair ( P=0.03) and days of open chest ( P=0.03) were associated with a lower composite language score, and length of stay was associated with a lower composite cognitive score ( P=0.02).

CONCLUSIONS

Surgery beyond 2 weeks of age is associated with impaired brain growth and slower language development in infants with transposition of the great arteries cared for at our center. Although the mechanisms underlying this association are still unclear, extended periods of cyanosis and pulmonary overcirculation may adversely impact brain growth and subsequent neurodevelopment.

Flame retardants in urban air: A case study in Toronto targeting distinct source sectors

Based on distinct land-use categories, a sampling campaign was carried out at eight locations across Toronto and the Greater Toronto Area in 2016-2017. Source sectors' dependent patterns of atmospheric concentrations of 9 organophosphate esters (OPEs), 9 polybrominated diphenyl ethers (PBDEs) and 5 novel flame retardants (NFRs) showed dominance of OPEs and PBDEs at highly commercialised urban and traffic sites, while NFRs, were dominant at residential sites. Overall, average concentrations of Σ₉OPEs (1790 pg/m³) were two orders of magnitude higher than Σ₉PBDEs (9.17 pg/m³) and Σ₅NFRs (8.14 pg/m³). The atmospheric concentrations of given chemical classes also showed a general trend of lower levels in winter as compared to summer months. Statistically significant negative correlations between the natural logarithm of concentrations and inverse of temperature for some OPEs and PBDEs highlighted the role of volatilization from local sources at given sites as primarily influencing their atmospheric concentrations. Overall, this study adds to the current knowledge of urban settings as a major emitter of the chemicals of emerging concern and their replacements, as well as the ongoing problem of phased out PBDEs due to their presence in existing inventories of commercial/recycled products. It is recommended that long-term monitoring programs targeting flame retardants (FRs) include urban sites, which provide an early indicator of effectiveness of control measures of targeted FRs, while at the same time providing information on emission sources and trends of replacement FR chemicals.

Organophosphate esters flame retardants in the indoor environment

Concentrations of 13 organophosphate ester flame retardants (OPEs) were measured in air, dust and window wipes from 63 homes in Canada, the Czech Republic and the United States in the spring and summer of 2013 to look for abundances, differences among regions, and partitioning behavior. In general, we observed the highest concentrations for halogenated OPEs, particularly TCEP, TCIPP and TDCIPP, and also non-halogenated TPHP. Differences between regions strongly depended on the matrix. The concentrations of OPEs in dust were significantly higher in the US than in Canada (CAN) and Czech Republic (CZ). CZ had the highest concentrations in window film and CAN in air. ΣOPE concentrations were 2-3 and 1-2 orders of magnitude greater than ΣBFRs in air, and dust and window films, respectively. We found a significant relationship between the concentrations in dust and air, and between the concentrations in window film and air for OPEs with log K_OA values <12, suggesting that equilibrium was reached for these compounds but not for those with log K_OA>12. This hypothesis was confirmed by a large discrepancy between values predicted using a partitioning model and the measured values for OPEs with log K_OA values >12.

Abstract 2373: Analysis of the distinct activities of the C1a and C1b domains of protein kinase C theta

PKC isozymes, the major receptors for tumor-promoting phorbol esters, play a central role in cellular signal transduction downstream of the second messenger diacylglycerol. The PKCθ isozyme has been extensively studied particularly in the context of hematopoiesis and immunity, where is required for the development and maturation of specific T cell subsets. PKCθ also plays a role in Notch-driven T cell leukemia and in a subset of gastrointestinal stromal tumors, melanoma and breast cancers. The C1 domains represent the regulatory motif in the PKCs responsible for their recognition of diacylglycerol / phorbol esters. PKCθ is unique among the conventional and novel PKC isoforms in that one of the two C1 domains of PKCθ, the C1a domain, has been reported to show little or no affinity for diacylglycerol or phorbol ester, unlike the C1b domain. Likewise, the PKCθ C1b domain has been reported to play the predominant role in the membrane translocation and activation process of PKCθ. We observed that the C1a domain in fact has appreciable binding activity for [3H]phorbol 12,13-dibutyrate (PDBu), with a Kd of 254 nM, albeit much less than that of the C1b domain, 1.58 nM. Replacing individually in the C1a domain ten of the amino acid residues that differed between the C1a and C1b domains, using the corresponding residue from the C1b domain, we found that only the P9K replacement restored [3H]phorbol 12,13-dibutyrate binding activity to the C1a domain, yielding a Kd of 3.60 nM, close to that of the C1b domain. Strikingly, the reciprocal replacement in the C1b domain of K9P still preserved appreciable binding affinity, 11.7 nM. We conclude that other features in the C1a domain contribute to the extent to which the P9 residue negatively influences binding. We further explored the role of the C1 domains of PKCθ on translocation using confocal microscopy with a variety of full length constructs in which the C1 domains were manipulated. Consistent with the binding studies, we showed that the C1b domain was the main contributor to translocation, that the full length PKCθ with the C1b K9P retained response, albeit more weakly, and that deletion of the C1a domain or its replacement with a second C1b domain enhanced the translocation to the plasma membrane. Exploitation of the structural differences between the C1 domains in PKCθ and those of other PKC isoforms, both at the level of the direct ligand interactions and the more complicated interplay between C1 domain, ligand, and phospholipid bilayer, may help to afford specific ligands for this member of the PKC family.

Citation Format: Agnes Czikora, Satyabrata Pany, Youngki You, Amandeep Saini, Noemi Kedei, Nancy E. Lewin, Adelle Abramovitz, Joydip Das, Peter M. Blumberg. Analysis of the distinct activities of the C1a and C1b domains of protein kinase C theta [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2373. doi:10.1158/1538-7445.AM2017-2373

From air to clothing: characterizing the accumulation of semi-volatile organic compounds to fabrics in indoor environments

Uptake kinetics of semi-volatile organic compounds (SVOCs) present indoors, namely phthalates and halogenated flame retardants (HFRs), were characterized for cellulose-based cotton and rayon fabrics. Cotton and rayon showed similar accumulation of gas- and particle-phase SVOCs, when normalized to planar surface area. Accumulation was 3-10 times greater by rayon than cotton, when normalized to Brunauer-Emmett-Teller (BET) specific surface area which suggests that cotton could have a longer linear uptake phase than rayon. Linear uptake rates of eight consistently detected HFRs over 56 days of 0.35-0.92 m³ /day.dm² planar surface area and mass transfer coefficients of 1.5-3.8 m/h were statistically similar for cotton and rayon and similar to those for uptake to passive air sampling media. These results suggest air-side controlled uptake and that, on average, 2 m² of clothing typically worn by a person would sequester the equivalent of the chemical content in 100 m³ of air per day. Distribution coefficients between fabric and air (K') ranged from 6.5 to 7.7 (log K') and were within the range of partition coefficients measured for selected phthalates as reported in the literature. The distribution coefficients were similar for low molecular weight HFRs, and up to two orders of magnitude lower than the equilibrium partition coefficients estimated using the COSMO-RS model. Based on the COSMO-RS model, time to reach 95% of equilibrium for PBDEs between fabric and gas-phase compounds ranged from 0.1 to >10 years for low to high molecular weight HFRs.

Acute Retropharyngeal Abscess Masquerading as Meningitis

Retropharyngeal abscess is a potentially serious deep neck space infection occurring more frequently in children than in adults. The clinical picture of RPA is highly variable with paucity of physical findings. Prompt diagnosis of RPA especially in infants is mandatory to prevent potential fatal complications including airway obstruction. The diagnosis of RPA should be based on high index of clinical suspicion with supportive imaging studies like lateral X-ray of neck and CT. We present a case of acute retropharyngeal abscess which was initially misdiagnosed as meningitis and led to airway obstruction. This case is reported to create awareness among emergency physicians, paediatricians and otolaryngologists to have high index of suspicion in diagnosing RPA especially in infants.

From Clothing to Laundry Water: Investigating the Fate of Phthalates, Brominated Flame Retardants, and Organophosphate Esters

The accumulation of phthalate esters, brominated flame retardants (BFRs) and organophosphate esters (OPEs) by clothing from indoor air and transfer via laundering to outdoors were investigated. Over 30 days cotton and polyester fabrics accumulated 3475 and 1950 ng/dm(2) ∑5phthalates, 65 and 78 ng/dm(2) ∑10BFRs, and 1200 and 310 ng/dm(2) ∑8OPEs, respectively. Planar surface area concentrations of OPEs and low molecular weight phthalates were significantly greater in cotton than polyester and similar for BFRs and high molecular weight phthalates. This difference was significantly and inversely correlated with KOW, suggesting greater sorption of polar compounds to polar cotton. Chemical release from cotton and polyester to laundry water was >80% of aliphatic OPEs (log KOW < 4), < 50% of OPEs with an aromatic structure, 50-100% of low molecular weight phthalates (log KOW 4-6), and < detection-35% of higher molecular weight phthalates (log KOW > 8) and BFRs (log KOW > 6). These results support the hypothesis that clothing acts an efficient conveyer of soluble semivolatile organic compounds (SVOCs) from indoors to outdoors through accumulation from air and then release during laundering. Clothes drying could as well contribute to the release of chemicals emitted by electric dryers. The results also have implications for dermal exposure.

Characterizing the sorption of polybrominated diphenyl ethers (PBDEs) to cotton and polyester fabrics under controlled conditions

Cotton and polyester, physically and chemically different fabrics, were characterized for sorption of gas-phase polybrominated diphenyl ethers (PBDEs). Scanning electron microscopic (SEM) images and BET specific surface area (BET-SSA) analysis showed cotton's high microsurface area; NMR analysis showed richness of hexose- and aromatic-carbon in cotton and polyester, respectively. Cotton and polyester sorbed similar concentrations of gas-phase PBDEs in chamber studies, when normalized to planar surface area. However, polyester concentrations were 20-50 times greater than cotton when normalized to BET-SSA, greater than the 10 times difference in BET-SSA. The difference in sorption between cotton and polyester is hypothesized to be due to 'dilution' due to cotton's large BET-SSA and/or greater affinity of PBDEs for aromatic-rich polyester. Similar fabric-air area normalized distribution coefficients (K'D, 10(3) to 10(4)m) for cotton and polyester support air-side controlled uptake under non-equilibrium conditions. K'D values imply that 1m(2) of cotton or polyester fabrics would sorb gas-phase PBDEs present in 10(3) to 10(4)m(3) of equivalent air volume at room temperature over one week, assuming similar air flow conditions. Sorption of PBDEs to fabrics has implications for their fate indoors and human exposure.

Brominated flame retardants in the indoor environment - Comparative study of indoor contamination from three countries

Concentrations of more than 20 brominated flame retardants (FRs), including polybrominated diphenyl ethers (PBDEs) and emerging FRs, were measured in air, dust and window wipes from 63 homes in Canada, the Czech Republic and the United States in the spring and summer of 2013. Among the PBDEs, the highest concentrations were generally BDE-209 in all three matrices, followed by Penta-BDEs. Among alternative FRs, EHTBB and BEHTBP were detected at the highest concentrations. DBDPE was also a major alternative FR detected in dust and air. Bromobenzenes were detected at lower levels than PBDEs and other alternative FRs; among the bromobenzenes, HBB and PBEB were the most abundant compounds. In general, FR levels were highest in the US and lowest in the Czech Republic - a geographic trend that reflects the flame retardants' market. No statistically significant differences were detected between bedroom and living room FR concentrations in the same house (n=10), suggesting that sources of FRs are widespread indoors and mixing between rooms. The concentrations of FRs in air, dust, and window film were significantly correlated, especially for PBDEs. We found a significant relationship between the concentrations in dust and window film and in the gas phase for FRs with log KOA values <14, suggesting that equilibrium was reached for these but not compounds with log KOA values >14. This hypothesis was confirmed by a large discrepancy between values predicted using a partitioning model and the measured values for FRs with log KOA values >14.

Product screening for sources of halogenated flame retardants in Canadian house and office dust

Human exposure to halogenated flame retardants (HFRs) such as polybrominated diphenyl ethers (PBDEs) and their replacements, can be related to exposure to indoor dust and direct contact with HFR-containing products. This study aimed to identify electronic products that contributed to HFRs measured in indoor dust and to develop a screening method for identifying HFRs in hard polymer products. Concentrations of 10 PBDEs and 12 halogenated replacements in dust and surface wipe samples of hard polymer casings of electronic products plus Br in the surfaces of those casing measured using X-ray fluorescence (XRF) were analyzed from 35 homes and 10 offices in Toronto (ON, Canada). HFR concentrations in dust and product wipes were positively correlated. Thus, we hypothesize that electronic products with the highest HFR concentrations contribute the most to concentrations in dust, regardless of the volatility of the HFR. Abundant HFRs in dust and product wipes were PBDEs (BDE-47, 99, 100, 153, 154, 183, 209), TDCPP, DBDPE, EH-TBB and BEHTBP. Older CRT TVs had the highest concentration of BDE-209 of all products tested. This was followed by higher concentrations of HFRs in PCs, Audio/Video (A/V) devices, small household appliances (HHAs) and flat screen TVs. The removal of HFRs from polymer surfaces using wipes supports concerns that HFRs could be transferred from these surfaces to hands as a result of direct contact with HFR-containing products. Surface wipe testing shows promise for screening additive HFRs. In comparison, the Br-content obtained using a handheld XRF analyzer did not correspond to concentrations obtained from surface wipe testing.

Calibration of two passive air samplers for monitoring phthalates and brominated flame-retardants in indoor air

Two passive air samplers (PAS), polyurethane foam (PUF) disks and Sorbent Impregnated PUF (SIP) disks, were characterized for uptake of phthalates and brominated flame-retardants (BFRs) indoors using fully and partially sheltered housings. Based on calibration against an active low-volume air sampler for gas- and particle-phase compounds, we recommend generic sampling rates of 3.5±0.9 and 1.0±0.4 m(3)/day for partially and fully sheltered housing, respectively, which applies to gas-phase phthalates and BFRs as well as particle-phase DEHP (the later for the partially sheltered PAS). For phthalates, partially sheltered SIPs are recommended. Further, we recommend the use of partially sheltered PAS indoors and a deployment period of one month. The sampling rate for the partially sheltered PUF and SIP of 3.5±0.9 m(3)/day is indistinguishable from that reported for fully sheltered PAS deployed outdoors, indicating the role of the housing outdoors to minimize the effect of variable wind velocities on chemical uptake, versus the partially sheltered PAS deployed indoors to maximize chemical uptake where air flow rates are low.

Interleukin-6 in combination with the interleukin-6 receptor stimulates glucose uptake in resting human skeletal muscle independently of insulin action

AIM

To examine if the physiological concentrations of both interleukin-6 (IL-6), in combination with IL-6 receptor (IL-6R), are able to stimulate glucose uptake in human skeletal muscle and to identify the associated signalling pathways.

METHODS

Skeletal muscle tissue (~60 mg) obtained from healthy female volunteers via muscle biopsy was subjected to incubation in the absence or presence of insulin (60 µU/ml), recombinant human IL-6 (rhIL-6) (4 ng/ml) or a combination of rhIL-6 (4 ng/ml) and rhIL-6R (100 ng/ml) for 30 min, with glucose transport measured for each incubation. Western blot analysis was conducted on key signalling proteins, protein kinase B (PKB/Akt), adenosine monophosphate kinase (AMPK) and mammalian target of rapamycin (mTOR) to gain an early insight into any differing transport mechanisms.

RESULTS

Human skeletal muscle exhibited increased glucose uptake with insulin (1.85-fold; p < 0.05) and stimulated phosphorylation of PKB/Akt and AMPK (0.98 ± 0.23 and 1.49 ± 0.13, respectively, phosphorylated: total; p < 0.05). IL-6/IL-6R increased phosphorylation of mTOR (fourfold, p < 0.05) compared to insulin, IL-6 alone and basal control. IL-6 did not stimulate glucose uptake but combined with IL-6R, induced 1.5-fold increase in glucose uptake (p < 0.05) and phosphorylation of AMPK (0.95 ± 0.19; phosphorylated: total, p < 0.05).

CONCLUSIONS

IL-6 in combination with IL-6R and not IL-6 alone increased glucose uptake in human skeletal muscle. IL-6/IL-6R-mediated glucose uptake occurred independently of PKB/Akt phosphorylation, showing that IL-6/IL-6R-induced glucose uptake is dependent on a divergent pathway.