Nitrogen processing by treatment wetlands in a tropical catchment dominated by agricultural landuse.

Agriculture is a major contributor to marine nitrogen pollution, and treatment wetlands can be a strategy to reduce it. However, few studies have assessed the potential of treatment wetlands to mitigate nitrogen pollution in tropical regions. We quantify the nitrogen removal rates of four recently constructed treatment wetlands in tropical Australia. We measured denitrification potential (Dt), the inflow-outflow of nutrients, and tested whether the environment in these tropical catchments is favourable for nitrogen removal. Dt was detected in three of the four systems with rates between 2.0 and 12.0 mg m-2 h-1; the highest rates were measured in anoxic soils (ORP -100 to 300 mV) that were rich in carbon and nitrogen (>2% and >0.2%, respectively). The highest nitrogen removal rates were measured when NO3--N concentrations were >0.4 mg L-1 and when water flows were slow. Treatment wetlands in tropical regions can deliver high removal rates of nitrogen and other pollutants when adequately managed. This strategy can reduce nutrient loads and their impacts on sensitive coastal zones such as the Great Barrier Reef.

Regional Rural-Urban Differences in E-Cigarette Use and Reasons for Use in the United States.

PURPOSE: To determine whether there are rural/urban differences in e-cigarette use and reasons for use that vary across the 10 Health & Human Services (HHS) regions. METHODS: Age-adjusted bivariate and multivariable analyses were conducted for n = 225,413 respondents to the 2014-2015 Tobacco Use Supplement-Current Population Survey to estimate the prevalence of e-cigarette use. Reasons for e-cigarette use were collected from n = 16,023 self-respondents who reported ever using e-cigarettes. FINDINGS: While nationally rural residents appeared more likely to use e-cigarettes, adjusted results indicated that current e-cigarette use was significantly less likely across the northern and western regions (New England, East North Central, Heartland, North Central Mountain, Northwest, and Southwest Pacific regions). Reasons for e-cigarette use differed by urban/rural status and region; for example, the rationale to use e-cigarettes as a smoking cessation aid was significantly more common among rural compared to urban adults in the New England and New York/New Jersey regions, but less common in the Southeast. CONCLUSIONS: For several regions, there were no significant rural/urban differences in e-cigarette use and reasons for use. Yet those regions that present differences face the need to develop public health approaches to minimize urban/rural disparities in health education, services, and outcomes related to tobacco use, particularly where access to health care is limited. Public health campaigns and guidance for clinical care within HHS regions should be tailored to reflect regional differences in beliefs about e-cigarettes.

Trend differences in men and women in rural and urban U.S. settings.

BACKGROUND: Smoking prevalence is declining at a slower rate in rural than urban settings in the United States (U.S.), and known predictors of smoking do not readily account for this trend difference. Given that socioeconomic and psychosocial determinants of health disparities accumulate in rural settings and that life-course disadvantages are often greater in women than men, we examined whether smoking trends are different for rural and urban men and women. METHOD: We used yearly cross-sectional data (n = 303,311) from the U.S. National Survey on Drug Use and Health (NSDUH) from 2007 through 2014 to compare cigarette smoking trends in men and women across rural and urban areas. Current smoking status was modelled using logistic regression controlling for confounding risk factors. RESULTS: Regression derived graphs predicting unadjusted prevalence estimates and 95% confidence bands revealed that whereas the smoking trends of rural men, urban men, and urban women significantly declined from 2007 to 2014, the trend for rural women was flat. Controlling for demographic, socioeconomic and psychosocial predictors of smoking did not explain rural women's significantly different trend from those of the other three groups. CONCLUSION: Rural women lag behind rural men, urban men and urban women in decreasing smoking, a health disparity finding that supports the need for tobacco control and regulatory policies and interventions that are more effective in reducing smoking among rural women.

De novo donor-specific antibodies in belatacept-treated vs cyclosporine-treated kidney-transplant recipients: Post hoc analyses of the randomized phase III BENEFIT and BENEFIT-EXT studies.

Donor-specific antibodies (DSAs) are associated with an increased risk of antibody-mediated rejection and graft failure. In BENEFIT and BENEFIT-EXT, kidney-transplant recipients were randomized to receive belatacept more intense (MI)-based, belatacept less intense (LI)-based, or cyclosporine-based immunosuppression for up to 7 years (84 months). The presence/absence of HLA-specific antibodies was determined at baseline, at months 6, 12, 24, 36, 48, 60, and 84, and at the time of clinically suspected episodes of acute rejection, using solid-phase flow-cytometry screening. Samples from anti-HLA-positive patients were further tested with a single-antigen bead assay to determine antibody specificities, presence/absence of DSAs, and mean fluorescence intensity (MFI) of any DSAs present. In BENEFIT, de novo DSAs developed in 1.4%, 3.5%, and 12.1% of belatacept MI-treated, belatacept LI-treated, and cyclosporine-treated patients, respectively. The corresponding values in BENEFIT-EXT were 3.8%, 1.1%, and 11.2%. Per Kaplan-Meier analysis, de novo DSA incidence was significantly lower in belatacept-treated vs cyclosporine-treated patients over 7 years in both studies (P < .01). In patients who developed de novo DSAs, belatacept-based immunosuppression was associated with numerically lower MFI vs cyclosporine-based immunosuppression. Although derived post hoc, these data suggest that belatacept-based immunosuppression suppresses de novo DSA development more effectively than cyclosporine-based immunosuppression.

Posttransplant reduction in preexisting donor-specific antibody levels after belatacept- versus cyclosporine-based immunosuppression: Post hoc analyses of BENEFIT and BENEFIT-EXT.

BENEFIT and BENEFIT-EXT were phase III studies of cytotoxic T-cell crossmatch-negative kidney transplant recipients randomized to belatacept more intense (MI)-based, belatacept less intense (LI)-based, or cyclosporine-based immunosuppression. Following study completion, presence/absence of HLA-specific antibodies was determined centrally via solid-phase flow cytometry screening. Stored sera from anti-HLA-positive patients were further tested with a single-antigen bead assay to determine antibody specificities, presence/absence of donor-specific antibodies (DSAs), and mean fluorescent intensity (MFI) of any DSAs present. The effect of belatacept-based and cyclosporine-based immunosuppression on MFI was explored post hoc in patients with preexisting DSAs enrolled to BENEFIT and BENEFIT-EXT. In BENEFIT, preexisting DSAs were detected in 4.6%, 4.9%, and 6.3% of belatacept MI-treated, belatacept LI-treated, and cyclosporine-treated patients, respectively. The corresponding values in BENEFIT-EXT were 6.0%, 5.7%, and 9.2%. In both studies, most preexisting DSAs were of class I specificity. Over the first 24 months posttransplant, a greater proportion of preexisting DSAs in belatacept-treated versus cyclosporine-treated patients exhibited decreases or no change in MFI. MFI decline was more apparent with belatacept MI-based versus belatacept LI-based immunosuppression in both studies and more pronounced in BENEFIT-EXT versus BENEFIT. Although derived post hoc, these data suggest that belatacept-based immunosuppression decreases preexisting DSAs more effectively than cyclosporine-based immunosuppression.

Belatacept-Resistant Rejection Is Associated With CD28+ Memory CD8 T Cells.

Recently, newer therapies have been designed to more specifically target rejection in an effort to improve efficacy and limit unwanted toxicity. Belatacept, a CD28-CD80/86 specific reagent, is associated with superior patient survival and graft function compared with traditional therapy, but its adoption as a mainstay immunosuppressive therapy has been tempered by increased rejection rates. It is essential that the underlying mechanisms associated with this rejection be elucidated before belatacept is more widely used. To that end, we designed a study in a nonhuman primate kidney transplant model where animals were treated with either a belatacept- or a tacrolimus-based immunosuppressive regimen. Interestingly, we found that elevated pretransplant frequencies of CD28+ CD8+ TEMRA cells are associated with rejection on belatacept but not tacrolimus treatment. Further analysis showed that the CD28+ CD8+ TEMRA cells rapidly lose CD28 expression after transplant in those animals that go on to reject with the allograft infiltrate being predominantly CD28- . These data suggest that CD28+ memory T cells may be resistant to belatacept, capable of further differentiation including loss of CD28 expression while maintaining effector function. The unique signaling requirements of CD28+ memory T cells provide opportunities for the development of targeted therapies, which may synergize with belatacept to prevent costimulation-independent rejection.

Targeting Lyn regulates Snail family shuttling and inhibits metastasis.

The acquisition of an invasive phenotype by epithelial cells occurs through a loss of cellular adhesion and polarity, heralding a multistep process that leads to metastatic dissemination. Since its characterization in 1995, epithelial-mesenchymal transition (EMT) has been closely linked to the metastatic process. As a defining aspect of EMT, loss of cell adhesion through downregulation of E-cadherin is carried out by several transcriptional repressors; key among them the SNAI family of transcription factors. Here we identify for the first time that Lyn kinase functions as a key modulator of SNAI family protein localization and stability through control of the Vav-Rac1-PAK1 (Vav-Rac1-p21-activated kinase) pathway. Accordingly, targeting Lyn in vitro reduces EMT and in vivo reduces metastasis of primary tumors. We also demonstrate the clinical relevance of targeting Lyn as a key player controlling EMT; patient samples across many cancers revealed a strong negative correlation between Lyn and E-cadherin, and high Lyn expression in metastatic tumors as well as metastasis-prone primary tumors. This work reveals a novel pancancer mechanism of Lyn-dependent control of EMT and further underscores the role of this kinase in tumor progression.

A growing geographic disparity: Rural and urban cigarette smoking trends in the United States.

Rural areas of the United States have a higher smoking prevalence than urban areas. However, no recent studies have rigorously examined potential changes in this disparity over time or whether the disparity can be explained by demographic or psychosocial characteristics associated with smoking. The present study used yearly cross sectional data from the National Survey on Drug Use and Health from 2007 through 2014 to examine cigarette smoking trends in rural versus urban areas of the United States. The analytic sample included 303,311 respondents. Two regression models were built to examine (a) unadjusted rural and urban trends in prevalence of current smoking and (b) whether differences remained after adjusting for demographic and psychosocial characteristics. Results of the unadjusted model showed disparate and diverging cigarette use trends during the 8-year time period. The adjusted model also showed diverging trends, initially with no or small differences that became more pronounced across the 8-year period. We conclude that differences reported in earlier studies may be explained by differences in rural versus urban demographic and psychosocial risk factors, while more recent and growing disparities appear to be related to other factors. These emergent differences may be attributable to policy-level tobacco control and regulatory factors that disproportionately benefit urban areas such as enforcement of regulations around the sale and marketing of tobacco products and treatment availability. Strong federal policies and targeted or tailored interventions may be important to expanding tobacco control and regulatory benefits to vulnerable populations including rural Americans.

Cytosolic 5'-nucleotidase 1A autoantibody profile and clinical characteristics in inclusion body myositis.

OBJECTIVES: Autoantibodies directed against cytosolic 5'-nucleotidase 1A have been identified in many patients with inclusion body myositis. This retrospective study investigated the association between anticytosolic 5'-nucleotidase 1A antibody status and clinical, serological and histopathological features to explore the utility of this antibody to identify inclusion body myositis subgroups and to predict prognosis. MATERIALS AND METHODS: Data from various European inclusion body myositis registries were pooled. Anticytosolic 5'-nucleotidase 1A status was determined by an established ELISA technique. Cases were stratified according to antibody status and comparisons made. Survival and mobility aid requirement analyses were performed using Kaplan-Meier curves and Cox proportional hazards regression. RESULTS: Data from 311 patients were available for analysis; 102 (33%) had anticytosolic 5'-nucleotidase 1A antibodies. Antibody-positive patients had a higher adjusted mortality risk (HR 1.89, 95% CI 1.11 to 3.21, p=0.019), lower frequency of proximal upper limb weakness at disease onset (8% vs 23%, adjusted OR 0.29, 95% CI 0.12 to 0.68, p=0.005) and an increased prevalence of excess of cytochrome oxidase deficient fibres on muscle biopsy analysis (87% vs 72%, adjusted OR 2.80, 95% CI 1.17 to 6.66, p=0.020), compared with antibody-negative patients. INTERPRETATION: Differences were observed in clinical and histopathological features between anticytosolic 5'-nucleotidase 1A antibody positive and negative patients with inclusion body myositis, and antibody-positive patients had a higher adjusted mortality risk. Stratification of inclusion body myositis by anticytosolic 5'-nucleotidase 1A antibody status may be useful, potentially highlighting a distinct inclusion body myositis subtype with a more severe phenotype.

Lyn activity protects mice from DSS colitis and regulates the production of IL-22 from innate lymphoid cells.

Intestinal homeostasis requires a complex balance of interactions between diverse resident microbial communities, the intestinal epithelium, and the underlying immune system. We show that the Lyn tyrosine kinase, a critical regulator of immune cell function and pattern-recognition receptor (PRR) responses, has a key role in controlling gastrointestinal inflammation. Lyn⁻/⁻ mice were highly susceptible to dextran sulfate sodium (DSS)-induced colitis, whereas Lyn gain-of-function (Lyn(up)) mice exhibited attenuated colitis during acute and chronic models of disease. Lyn(up) mice were hypersensitive to lipopolysaccharide (LPS), driving enhanced production of cytokines and factors associated with intestinal barrier function, including interleukin (IL)-22. Oral administration of LPS was sufficient to protect antibiotic-treated Lyn(up) but not wild-type mice from DSS, highlighting how Lyn-dependent changes in the nature/magnitude of PRR responses can impact intestinal health. Furthermore, protection from DSS-induced colitis and increased IL-22 production in response to LPS did not depend on the adaptive immune system, with increased innate lymphoid cell-derived IL-22 correlating with Lyn activity in dendritic cells. These data reveal a key role for Lyn in the regulation of innate immune responses and control of intestinal inflammation.

CCR3 induced-p42/44 MAPK activation protects against staurosporine induced-DNA fragmentation but not apoptosis in airway smooth muscle cells.

BACKGROUND: Chemokine receptors (CCRs) are expressed on airway smooth muscle (ASM) cells. As their ligands are present in the airways in asthma, we hypothesized that ASM CCR activation could promote the increase in ASM mass seen in patients with chronic asthma. OBJECTIVE: To determine which CCRs are expressed by ASM cells and their potential functional relevance to the chronic airway changes seen in asthma. METHODS: CCR expression in primary ASM cell cultures and airway biopsies from patients with and without asthma was examined by RT-PCR, fluorescence-activated cell sorting and immunohistochemistry. ASM p42/44 MAPK activity, proliferation, migration and apoptosis were examined by western blotting, thymidine incorporation, transwell assay and TUNEL assay respectively. RESULTS: CCR3 was the most frequently expressed CCR protein and was present on 79 ± 14% of cells. CX3CR1 and CXCR6 were present on 6% and 11% of cells respectively. CCR3 ligands CCL11 and CCL24 caused rapid activation of p42/44 MAPK but not Akt. CCR3 activation did not affect ASM proliferation, migration or VEGF secretion. DNA fragmentation detected by TUNEL staining could be induced by staurosporine and Fas activation although only Fas activation resulted in caspase 3 cleavage. CCL11 and CCL24 protected ASM cells against DNA fragmentation dependent upon p42/44 MAPK activity only via caspase 3 independent pathways. CCR3 was expressed in the smooth muscle and epithelium in the airways of patients with and without asthma. Smooth muscle cell DNA fragmentation in the airways of patients with stable asthma and controls was very uncommon. CONCLUSIONS AND CLINICAL RELEVANCE: CCR3 is strongly expressed by ASM cells in vitro and in vivo. Protection against cell death by CCR3 activation is dependent on p42/44 MAPK but does not affect caspase 3 mediated apoptosis.

Chronic cold acclimation increases thermogenic capacity, non-shivering thermogenesis and muscle citrate synthase activity in both wild-type and brown adipose tissue deficient mice.

The purpose of this study was to determine whether chronic cold exposure would increase the aerobic capacity of skeletal muscle in UCP-dta mice, a transgenic line lacking brown adipose tissue (BAT). Wild type and UCP-dta mice were acclimated to either warm (23 °C), or cold (4 °C) conditions. Cold increased muscle oxidative capacity nearly equivalently in wild-type and UCP-dta mice, but did not affect the respiratory function of isolated mitochondria. Summit metabolism ( ̇V O2summit) and norepinephrine-induced thermogenesis ( ̇V O2NST) were significantly lower in UCP-dta mice relative to wild-type mice regardless of temperature treatment, but both were significantly higher in cold relative to warm acclimated mice. BAT mass was significantly higher in the cold relative to warm acclimated wild-type mice, but not in cold acclimated UCP-dta mice. BAT citrate synthase activity was lower in transgenic animals regardless of acclimation temperature and BAT citrate synthase activity per depot was significantly higher only in the cold acclimated wild-type mice. Muscle citrate synthase activity was increased in both genotypes. As defects in muscle oxidative function have been observed with obesity and type 2 diabetes, these results suggest that chronic cold exposure is a useful intervention to drive skeletal muscle oxidative capacity in mouse models of obesity.

Socioeconomic deprivation, readmissions, mortality and acute exacerbations of bronchiectasis.

BACKGROUND: Bronchiectasis is known to cause significant morbidity in children in New Zealand. Little is known of the disease in adults. AIM: Our objective was to characterise a cohort of adults who presented to hospital with acute exacerbations of the disease. METHODS: We retrospectively collected information on all exacerbations treated as inpatients from a single hospital in South Auckland, New Zealand during 2002. RESULTS: We collected information on 307 exacerbations in 152 patients. Twenty-seven per cent were of Maaori ethnic origin, and 44% Pacific. Seventy per cent lived in areas categorised as the 20% most deprived in New Zealand. Comorbid conditions were present in 80% of patients - most commonly chronic obstructive pulmonary disease, asthma, diabetes and cardiac disease. Seventy (46%) patients had at least one readmission and 32 patients (21%) died within 12 months of admission to hospital. Greater deprivation was associated with increased mortality at 12 months after admission after adjusting for other factors (OR 11, 95% CI 2.0-61, P= 0.006). In the subgroup who underwent high-resolution computed tomographic scanning (93), increasing severity of bronchiectasis (modified Bhalla score) was associated with readmission within 12 months (P= 0.004), but not mortality (P= 0.419). CONCLUSIONS: We have shown that exacerbations of bronchiectasis in South Auckland are more common in patients who are predominantly of Maaori or Pacific descent and are socioeconomically deprived. Admission to hospital for an exacerbation is associated with high readmission and mortality rates.

Salivary anti-Ro60 and anti-Ro52 antibody profiles to diagnose Sjogren's Syndrome.

Simple and non-invasive saliva-based diagnostics may be useful for the identification, understanding, and monitoring of autoimmune and infectious diseases. Previously, Luciferase Immunoprecipitation Systems (LIPS) were used for sensitive detection of patient serum autoantibodies in Sjögren's Syndrome (SjS), a chronic autoimmune disease affecting the salivary and lacrimal glands. Here we explored the ability of LIPS to diagnose SjS based on IgG autoantibodies in patient saliva. From LIPS testing, anti-Ro60 autoantibodies were detected in the saliva of 70% (19/27) of SjS patients with 96% specificity. Positive anti-Ro60 autoantibodies were also found in 70% of the matched serum samples (96% specificity). LIPS detected Ro52 autoantibodies in the saliva and serum of 67% of SjS patients with 100% specificity. Overall, the autoantibody titers in saliva were approximately 4000-fold lower by volume than serum, but still distinguished seropositive patients from controls. These results suggest that LIPS salivary-based testing for SjS autoantibodies is a practical alternative to serum and compatible with point-of-care testing.

Discoidin domain receptor 1 regulates bronchial epithelial repair and matrix metalloproteinase production.

Discoidin domain receptor (DDR)1 is an extracellular matrix (ECM)-sensing receptor tyrosine kinase, which is activated by collagen and expressed in bronchial epithelium. DDR1 is responsible for maintaining the normal structure of skin and kidney epithelia and we hypothesised that DDR1 plays a regulatory role in bronchial epithelial integrity by transducing signals from the airway ECM. Effects of DDR1 depletion were studied using RNA interference in primary human bronchial epithelial cells (HBECs) and BEAS-2B cells. The effects of overexpression of DDR1a and DDR1b in BEAS-2B cells were studied using a plasmid vector. We measured the effects on epithelial repair using a scratch wounding model, and levels of matrix metalloproteinases (MMPs) by gelatin zymography (MMP-2 and -9) and ELISA (MMP-7). We showed that knockdown of DDR1 slowed epithelial repair by 50%, which was associated with a reduction in levels of MMP-7, whilst DDR1 overexpression enhanced epithelial repair. DDR1 knockdown reduced proliferation of HBECs, but had no significant effect on adhesion to collagen I or other matrix substrates. These data suggest that ECM signalling via DDR1 regulates aspects of bronchial epithelial repair, integrity and MMP expression in the airways.

Withdrawal of somatostatin analogue therapy in patients with acromegaly is associated with an increased risk of acute biliary problems.

BACKGROUND: The prevalence of gallstones (GS) is increased in acromegaly and further increased by somatostatin analogue (SA) therapy. The incidence is reported at 10-63%, but they are often asymptomatic and rarely require definitive management. Evidence suggests discontinuation of SA may precipitate acute biliary problems. OBJECTIVE: To determine the frequency of symptomatic gallstones in patients treated with SA. DESIGN: Retrospective analysis of prospectively followed patients in our centre. RESULTS: Fifty patients (30 male, mean age 54 +/- 16 years) were on treatment with SA on 1 January 2003. Fifteen (11 male, mean age 50 +/- 17 years) have since discontinued SA with three proceeding to develop acute cholecystitis and two, biliary colic necessitating cholecystectomy. Three of the five had abnormal liver enzymes at or within 3 months of symptomatic presentation. Two of the remaining 35 patients experienced biliary colic necessitating cholecystectomy. These data indicate a highly significant increase in acute biliary problems on discontinuing SA (5 in 27.67 patient 'off-treatment' years vs. 2 in 299 patient treatment years, chi(2), P < 0.0001). All seven patients experiencing problems were male (P = 0.01). CONCLUSION: This analysis demonstrates the high incidence of symptomatic GS following SA withdrawal, particularly in men. Although liver enzymes were raised no common abnormality was evident to aid as a predictor of future symptoms. We recommend all patients due to stop SA be forewarned of the risk of acute biliary problems. Further work is required to confirm if there is a gender-related difference in the incidence of acute biliary problems on discontinuing SA therapy.

Reductions of circulating matrix metalloproteinase 2 and vascular endothelial growth factor levels after treatment with pegvisomant in subjects with acromegaly.

BACKGROUND: Vascular endothelial growth factor (VEGF) is involved in activation of the matrix metalloproteinase (MMP) system; the latter is implicated in atherosclerosis and cardiovascular disease. Patients with acromegaly have reduced life expectancy primarily due to cardiac disease. AIM: This study assessed plasma MMPs and VEGF levels in patients with active acromegaly (IGF-I > 130% upper limit of normal), and on treatment with pegvisomant. SUBJECTS AND METHODS: Twenty patients [nine female, mean age 56.1 +/- 13.8 yr (mean +/- sd)] were studied at baseline and on pegvisomant therapy and compared with data from 25 healthy volunteers (12 female; 56.6 +/- 14.2 yr). Plasma MMP-2, MMP-9, and VEGF levels were measured. RESULTS: Serum IGF-I fell from a baseline (mean +/- sd) level of 620.1 +/- 209.3 ng/ml to 237.5 +/- 118.5 ng/ml on pegvisomant (doses 10-60 mg; P < 0.001). MMP-2 levels at baseline were significantly higher in patients compared with healthy controls (380.7 +/- 204.8 vs. 207.4 +/- 62.6 ng/ml; P < 0.001), but with treatment a significant reduction in MMP-2 [380.7 +/- 204.8 vs. 203.0 +/- 77.4 ng/ml; P < 0.001] and VEGF (283.4 +/- 233.6 vs. 229.1 +/- 157.4 pg/ml; P = 0.008) was noted. There was no significant difference in MMP-9 levels between patients and controls at baseline (797.5 +/- 142.1 vs. 788.3 +/- 218.0 ng/ml; P = 0.87) or between baseline and posttreatment levels (797.5 +/- 142.1 vs. 780.0 +/- 214 ng/ml; P = 0.76). CONCLUSIONS: Our novel data demonstrate that treatment of acromegaly with pegvisomant leads to reductions in MMP-2 and VEGF concentrations. Further studies are required to determine the significance of these findings with relation to cardiac disease.