A cross-reactive plasmonic sensing array for drinking water assessment.

The continuous monitoring of remote drinking water purification systems is a global challenge with direct consequences for human and environmental health. Here, we utilise a "nano-tastebud" sensor comprised of eight chemically-tailored plasmonic metasurfaces, for testing the composition of drinking water. Through undertaking a full chemometric analysis of the water samples and likely contaminants we were able to optimise the sensor specification to create an array of suitable tastebuds. By generating a unique set of optical responses for each water sample, we show that the array-based sensor can differentiate between untreated influent and treated effluent water with over 95% accuracy in flow and can detect compositional changes in distributed modified tap water. Once fully developed, this system could be integrated into water treatment facilities and distribution systems to monitor for changes in water composition.

CRM rapid response approach for the certification of arsenic species and toxic trace elements in baby cereal coarse rice flour certified reference material BARI-1.

With recently legislated maximum levels of inorganic arsenic (iAs) in white and brown rice in Canada, the regulatory bodies are evaluating the need for regulation of As levels in infant food products. Rice is a major part of infants' diet, and therefore, the presence of As in this staple food causes concerns. So far, the scientific community was lacking suitable certified reference material (CRM) which could be used to assess the accuracy of developed analytical methods for As speciation in infants' food products. As a result, we have developed BARI-1, a baby cereal coarse rice flour reference material which was certified for total arsenic (0.248 ± 0.018 mg kg-1), cadmium (0.0134 ± 0.0014 mg kg-1), mercury (0.0026 ± 0.0003 mg kg-1), lead (0.0064 ± 0.0016 mg kg-1), inorganic As (0.113 ± 0.016 mg kg-1) and dimethylarsinic acid (DMA) (0.115 ± 0.010 mg kg-1), and reference value for monomethylarsonic acid (MMA) (0.0045 ± 0.0008 mg kg-1) was reported. We also observed trace amounts of an unknown As compound, with chromatographic retention time close to DMA. Participating laboratories were allowed to use their in-house-validated extraction and/or digestion methods, and the detection of total metals was done by ICP-MS whereas HPLC-ICP-MS was used for As speciation. Despite the diversity in sample preparation and quantitation methods, reported values were in good agreement. For iAs measurement, the comparison between hydride generation ICP-MS and HPLC-ICP-MS found iAs overestimation with the former method, possibly due to interference from DMA. The certification was accomplished with a CRM rapid response approach in collaborative, focused effort completing the CRM development in few months instead of the typical multiyear project. This approach allowed to respond to measurement needs in a timely fashion. Graphical abstract.

Maritime Deposition of Organic and Inorganic Arsenic.

The speciation of arsenic in wet and dry deposition are ambiguously described in current literature. Presented here is a 2 year study quantifying arsenic species in atmospheric deposition collected daily from an E. Atlantic coastal, semirural site, with comparative urban locations. Inorganic arsenic (Asi) was the principal form of arsenic in wet deposition, with a mean concentration of 0.54 µmol/m3. Trimethylarsine oxide (TMAO) was found to be the dominant form of organic arsenic, determined as above the LoD in 33% of wet deposition samples with a mean concentration of 0.12 µmol/m3. Comparison with codeposited trace elements and prevailing weather trajectories indicated that both anthropogenic and marine sources contribute to atmospheric deposition. Analysis of dry deposition revealed it to be a less significant input to the land-surface for Asi, contributing 32% of that deposited by wet deposition. Dry deposition had a larger proportion of Asi than that found in wet deposition, with TMAO making up only 12% of the sum of species. In comparison, urban sites showed large spatial and temporal variations in organic arsenic deposition, indicating that local sources of methylated species may be likely and that further understanding of biogenic arsine evolution and degradation are required to adequately assess the atmospheric arsenic burden and subsequent contribution to terrestrial ecosystems.

Modifying the Parboiling of Rice to Remove Inorganic Arsenic, While Fortifying with Calcium.

Using village-based rice processing plants in rural Bangladesh, this study considered how parboiling rice could be altered to reduce the content of the carcinogen inorganic arsenic. Parboiling is normally conducted with rough rice (i.e., where the husk is intact) that is soaked overnight at ambient temperatures, and then either steamed or boiled for ∼10 min, followed by drying. Across 13 geographically dispersed facilities it was found that a simple alteration parboiling wholegrain, instead of rough rice, decreased the inorganic arsenic content by 25% ( P = 0.002) in the final polished grain. Also, parboiling wholegrain had little impact on milling quality of the final polished rice. The wholegrain parboiling approach caused statistically significant median enrichment of calcium, by 213%; and a reduction in potassium, by 40%; with all other nutrient elements tested being unaffected. Milled parboiled rough rice had an enriched inorganic arsenic compared to nonparboiled milled rice, but parboiling of wholegrain rice did not enrich inorganic arsenic in the final milled product. Polished rice produced from the parboiling of both rough and wholegrain rice significantly reduced cadmium compared to nonparboiled polished rice, by 25%. This study also identified that trimethylarsine oxide and tretramethylarsonium are widely elevated in the husk and bran of rice and, therefore, gives new insights into the biogeochemical cycling of arsenic in paddy ecosystems.

Biovolatilization of Arsenic as Arsines from Seawater.

Marine sources of arsenic to the atmosphere are normally dismissed as minor. Here we show that arsenic can be biovolatilized from seawater, and that biovolatilzation is based on organic arsenic species present in the seawater. Even though inorganic arsenic is in great excess in seawaters, it is trimethylarsine (TMA) that is the primary biovolatilized product, with dimethylarsine (DMA) also observed if dimethylarsinic acid (DMAA) is spiked into seawaters. With respect to budgets, 0.04% of the total arsenic in the seawater was biovolatilized over a 2-week incubation period. To test the environmental significance of this finding, wet deposition was analyzed for arsenic species at coastal locations, one of which was the origin of the seawater. It was found that the oxidized product of TMA, trimethylarsine oxide (TMAO), and to a less extent DMAA were widely present. When outputs for arsines (0.9 nmol/m2/d) from seawater and inputs from wet deposition (0.3-0.5 nmol/m2/d) were compared, they were of the same order of magnitude. These findings provide impetus to reexamining the global arsenic cycle, as there is now a need to determine the flux of arsines from the ocean to the atmosphere.

Elevated Trimethylarsine Oxide and Inorganic Arsenic in Northern Hemisphere Summer Monsoonal Wet Deposition.

For arsenic speciation, the inputs for wet deposition are not well understood. Here we demonstrate that trimethylarsine oxide (TMAO) and inorganic arsenic are the dominant species in monsoonal wet deposition in the summer Indian subcontinent, Bangladesh, with inorganic arsenic dominating, accounting for ∼80% of total arsenic in this medium. Lower concentrations of both species were found in monsoonal wet deposition in the winter Indian subcontinent, Sri Lanka. The only other species present was dimethylarsinic acid (DMAA), but this was usually below limits of detection (LoD). We hypothesize that TMAO and inorganic arsenic in monsoonal wet deposition are predominantly of marine origin. For TMAO, the potential source is the atmospheric oxidation of marine derived trimethylarsine. For inorganic arsenic, our evidence suggests entrainment of water column inorganic arsenic into atmospheric particulates. These conclusions are based on weather trajectory analysis and on the strong correlations with known wet deposition marine derived elements: boron, iodine, and selenium. The finding that TMAO and inorganic arsenic are widely present and elevated in monsoonal wet deposition identifies major knowledge gaps that need to be addressed regarding the understanding of arsenic's global cycle.

Analysis of the effect of the oral contraceptive pill on clinical outcomes in women with ankylosing spondylitis.

OBJECTIVE: There are unexplained sex-specific changes in the clinical expression of ankylosing spondylitis (AS). We sought to examine the potential effect of exogenous estrogen in the form of oral contraceptive pills (OCP) on AS initiation and severity. METHODS: This cross-sectional study consisted of women with AS from the membership of the Spondylitis Association of America. Measures of disease severity included use of biological agents and hip replacement surgery, while Bath AS Functional Index (BASFI) scores served as a surrogate marker of disability. Information was obtained using a patient questionnaire on patient demographics, OCP use, pregnancy history, AS duration, medication use, and hip replacement. RESULTS: There were 571 women with AS who participated in our study, consisting of 448 OCP ever-users and 123 non-OCP users. The mean age of OCP users was 42.7 yrs (± 11.5) and of non-OCP users, 48.4 yrs (± 12.1). No difference was noted in the age at initial onset of back pain. However, OCP users were significantly younger at the time of diagnosis of AS (36.5 yrs vs 39.1 yrs, p = 0.02). There were no significant differences between the 2 groups in tumor necrosis factor inhibitor or opioid use, BASFI scores, pregnancy complications, or hip surgery. CONCLUSION: The use of exogenous estrogens in the form of OCP is not associated with a measurable effect on initiation or severity of AS. Biologic and social factors may contribute to earlier diagnosis of AS in OCP users. This is the largest study to date investigating the potential effect of exogenous estrogens in women with AS.

New population-based reference values for spinal mobility measures based on the 2009-2010 National Health and Nutrition Examination Survey.

OBJECTIVE: To report population-based percentile reference values for selected spinal mobility measures in a nationally representative sample of 5,001 US adults ages 20-69 years who were examined in the 2009-2010 US National Health and Nutrition Examination Survey (NHANES). METHODS: Occiput-to-wall distance (OWD), thoracic expansion (TE), and anterior lumbar flexion (ALF; by modified Schober test) were measured by trained examiners in a standardized manner. TE was measured at the xiphisternal level, while the lower reference point for ALF was a line marked at the level of the superior margin of the lateral iliac crests. We report reference values based on the 95th percentile for the OWD and the 5th percentile for TE and ALF, as well as other summary statistics for these measures, in the study population. RESULTS: An OWD of >0 was present in 3.8% of the participants, while 8.8% of them had out-of-range values for TE based on the commonly used threshold of 2.5 cm. The 95th percentile of the OWD measurement was 0, while the 5th percentile for TE and ALF were 1.9 cm and 2 cm, respectively. The spinal measures were significantly associated with sex, age, ethnicity, height, and body mass index (BMI). Exclusion of individuals with severe obesity (BMI >35 kg/m(2) ) changed the proposed reference values for TE and ALF to 2.2 cm and 1.9 cm, respectively. CONCLUSION: We verified a reference value of 0 for the OWD in the general population. Using the reported population-based percentile values, new reference values for TE and ALF can be derived.

Insights into uveitis in association with spondyloarthritis from a large patient survey.

BACKGROUND: Uveitis is reported to be the most common extra-articular feature in spondyloarthritis (SpA). OBJECTIVE: The objective of this study was to investigate the relationship between uveitis and SpA in a cohort identified from a survey. METHODS: Eight hundred sixty-three respondents completed a survey conducted by the Spondylitis Association of America. Data on baseline demographics, quality of life, medication use, and joint involvement were compared in SpA patients with and without uveitis. Logistic regression analysis was used to identify characteristics associated with the presence of uveitis. RESULTS: Of the 863 respondents, 168 (19.5%) reported a diagnosis of uveitis. Baseline demographics including sex, age, and ethnicity were similar between the uveitis and no-uveitis groups. The presence of uveitis had a significant positive association with the use of the biologic drug infliximab (adjusted odds ratio [ORadj] = 1.66, P = 0.044), "lower jaw" involvement (ORadj = 1.60, P = 0.015), heel involvement (ORadj = 1.51, P = 0.023), and a diagnosis of arthritis associated with inflammatory bowel disease (ORadj = 1.92, P = 0.005). It had a significant negative association with the use of the biologic drug etanercept (ORadj = 0.49, P = 0.011) or a coexisting diagnosis of diabetes (ORadj = 0.02, P = 0.020). CONCLUSIONS: The relationship of uveitis to medication presumably reflects the choice of a specific tumor necrosis factor inhibitor in the setting of a history of uveitis. One prior study has also correlated heel pain and uveitis, thus supporting the validity of the association and suggesting potentially a common pathogenesis. Because diabetes has been proposed as a risk factor for uveitis, the negative association is surprising and may distinguish the pathogenesis of uveitis in association with SpA from other forms of uveitis.

Development and validation of a case ascertainment tool for ankylosing spondylitis.

OBJECTIVE: Ankylosing spondylitis (AS) diagnosis is often delayed. The availability of effective biologic agents for treating AS has increased the importance of early diagnosis. We tested questions derived from a comprehensive literature review and an advisory board in a case-control study designed to identify patients with AS from among patients with chronic back pain (CBP). METHODS: Question items were cognitively tested among patients with AS, and then in case-control studies for validation and creation of a scoring algorithm and question item reduction. AS cases were recruited from a known database, and CBP subjects (controls) were recruited from clinics, employers, and from the SpineUniverse Web site. We used individual question items in a multivariate framework to discriminate between people with and without AS. RESULTS: Forty-three questions yielded 24 items for analyses; 12 of these were entered into a multivariate regression model. Individual items yielded odds ratios ranging from 0.07 to 30.31. Question items with a significant positive relationship to AS included male sex, neck or hip pain/stiffness, longer pain duration, decreased pain/stiffness with daily physical activity, pain relief within 48 hours of nonsteroidal antiinflammatory drugs, and diagnosis of iritis. The tool demonstrated a sensitivity of 67.4 and a specificity of 94.6. The tool was developed from clinically and radiologically diagnosed AS cases and therefore is designed to distinguish AS cases among CBP subjects. In addition, approximately 54% of the AS cases in the study were treated with biologic agents, which may impact questionnaire responses. CONCLUSION: This tool can identify undiagnosed patients with AS and, potentially, those at an earlier stage in their disease course.

Visual assessment of the spine bruckel instrument, a novel status tool to reflect appearance of the spine in patients with ankylosing spondylitis.

OBJECTIVE: The Visual Assessment of the Spine Bruckel Instrument (VASBI) is a new status tool developed by the Spondylitis Association of America and the University of Toronto to reflect spinal appearance in patients with ankylosing spondylitis (AS). Our objective was to validate the VASBI according to the Outcome Measures in Rheumatoid Arthritis Clinical Trials filter (truth, discrimination, and feasibility). METHODS: Three hundred patients with AS were asked to rate their degree of perceived spinal deformity using the VASBI. To evaluate construct validity, VASBI scores were compared with functional outcome, spinal mobility, and radiographic spinal damage. Test-retest reliability was evaluated using kappa statistic (kappa). RESULTS: Patient VASBI demonstrated strong correlation with spinal mobility (r = 0.543) and moderate correlation with functional impairment (r = 0.490) and structural damage (r = 0.309). Reliability for VASBI was very good (kappa = 0.973, p < 0.001). CONCLUSION: The VASBI is a novel tool with practical applications in a busy clinical setting as it simplifies assessment of AS spinal deformity. Our study demonstrates that the VASBI has good feasibility, construct validity, and reliability.

Genome-wide association study of ankylosing spondylitis identifies non-MHC susceptibility loci.

To identify susceptibility loci for ankylosing spondylitis, we undertook a genome-wide association study in 2,053 unrelated ankylosing spondylitis cases among people of European descent and 5,140 ethnically matched controls, with replication in an independent cohort of 898 ankylosing spondylitis cases and 1,518 controls. Cases were genotyped with Illumina HumHap370 genotyping chips. In addition to strong association with the major histocompatibility complex (MHC; P < 10(-800)), we found association with SNPs in two gene deserts at 2p15 (rs10865331; combined P = 1.9 x 10(-19)) and 21q22 (rs2242944; P = 8.3 x 10(-20)), as well as in the genes ANTXR2 (rs4333130; P = 9.3 x 10(-8)) and IL1R2 (rs2310173; P = 4.8 x 10(-7)). We also replicated previously reported associations at IL23R (rs11209026; P = 9.1 x 10(-14)) and ERAP1 (rs27434; P = 5.3 x 10(-12)). This study reports four genetic loci associated with ankylosing spondylitis risk and identifies a major role for the interleukin (IL)-23 and IL-1 cytokine pathways in disease susceptibility.

The Canadian Rheumatology Association/ Spondyloarthritis Research Consortium of Canada treatment recommendations for the management of spondyloarthritis: a national multidisciplinary stakeholder project.

OBJECTIVE: Development of treatment recommendations for arthritis has traditionally relied on the compilation of evidence-based data by experts in the field despite recommendations by various bodies for broad stakeholder input. Our objectives were: (1) To develop evidence-based treatment recommendations for the management of spondyloarthritis (SpA) in Canada that also incorporate the perspective of multiple stakeholders. (2) To generate a procedural template for the multidisciplinary development of treatment recommendations. METHODS: The process was directed by a steering committee comprising the SPARCC Executive, rheumatologists from academic and community-based practice, patient consumers, and a representative from the John Dossetor Health Ethics Centre. Guidelines established by EULAR and stipulated in the AGREE instrument were followed. First, a working document was drafted that included a referenced summary of the evidence-based data and the 12 national arthritis care standards developed by the Alliance for the Canadian Arthritis Program. Second, a Web-based survey was conducted among patient consumers to address the relevance to patients of 2 primary outcome instruments that assess the effectiveness of treatment. Third, a list of questions was generated for drafting propositions by the ethics consultant. A Delphi consensus exercise was then conducted. RESULTS: Consensus was generated on a final list of 38 treatment recommendations categorized under the subject headings of general management principles, ethical considerations, target groups, definition of target disease, disease monitoring, and specific management recommendations. CONCLUSION: Using broad stakeholder input, we provide treatment recommendations to guide clinical practice and access to care for patients with SpA in Canada.