Generation of LexA enhancer-trap lines in Drosophila by an international scholastic network

Conditional gene regulation in Drosophila through binary expression systems like the LexA-LexAop system provides a superb tool for investigating gene and tissue function. To increase the availability of defined LexA enhancer trap insertions, we present molecular, genetic, and tissue expression studies of 301 novel Stan-X LexA enhancer traps derived from mobilization of the index SX4 line. This includes insertions into distinct loci on the X, II, and III chromosomes that were not previously associated with enhancer traps or targeted LexA constructs, an insertion into ptc, and seventeen insertions into natural transposons. A subset of enhancer traps was expressed in CNS neurons known to produce and secrete insulin, an essential regulator of growth, development, and metabolism. Fly lines described here were generated and characterized through studies by students and teachers in an international network of genetics classes at public, independent high schools, and universities serving a diversity of students, including those underrepresented in science. Thus, a unique partnership between secondary schools and university-based programs has produced and characterized novel resources in Drosophila, establishing instructional paradigms devoted to unscripted experimental science.

A212 THE IMPACT OF COMBINED MEDICAL AND SURGICAL TREATMENT FOR PERIANAL CROHN’S DISEASE: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Multidisciplinary care involving surgical drainage via examinations under anesthesia (EUA) and anti-tumor necrosis factor (TNF) therapy is recommended for perianal Crohn’s disease (PCD). However, the impact of this combined modality approach is not well-established.

Purpose

To determine the impact of combined modality (surgical and anti-TNF) vs. single modality (either surgical or anti-TNF) therapy on fistula healing in perianal Crohn’s disease.

Method

MEDLINE, EMBASE, and Cochrane databases were searched systematically from inception through September 15, 2022 independently in duplicate. We included studies that reported on fistula outcomes after treatment with combined modality vs. single modality therapy for PCD. Surgery was defined as EUA ± seton or closure procedure. Weighted summary estimates with 95% CI were estimated by random effects models. Study quality was determined using an adapted version of the Newcastle-Ottawa scale.

Result(s)

Thirteen studies met inclusion criteria. The total population included 1279 patients: 685 patients treated with single modality therapy with either surgical or anti-TNF therapy and 594 patients treated with combined modality therapy. Patients treated with combined modality therapy were more likely to achieve fistula healing compared to single modality therapy (65.4% vs. 57.7%; OR 1.68; 95% CI 1.03-2.73, p = 0.04) (Figure 1a). In a subgroup analysis, the rates of fistula healing were higher with combined modality therapy than with surgical therapy alone (OR 2.34; 95% CI 0.85-6.46, p = 0.10) but not anti-TNF therapy alone (OR 1.19; 95% CI 0.78-1.81, p = 0.43), although neither comparison was statistically significant (Figures 1b and c). The majority of studies were rated low-quality due to risk of bias from uncontrolled confounding variables.

Image

Conclusion(s)

Limited high-quality evidence suggests that fistula healing occurs more frequently in patients treated with combined modality therapy. However, the benefit of a combined modality approach appears to be driven mainly by anti-TNF therapy. Further prospective randomized trials are needed to confirm these findings.

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None

Disclosure of Interest

None Declared

Reproducibility of T1ρ and T2 quantification in a multi-vendor multi-site study

OBJECTIVE

To evaluate the multi-vendor multi-site reproducibility of two-dimensional (2D) multi-echo spin-echo (MESE) T2 mapping (product sequences); and to evaluate the longitudinal reproducibility of three-dimensional (3D) magnetization-prepared angle-modulated partitioned k-space spoiled gradient echo snapshots (MAPSS) T1ρ and T2 mapping (research sequences), and 2D MESE T2 mapping, separated by 6 months, in a multi-vendor multi-site setting.

METHODS

Phantoms and volunteers (n = 5 from each site, n = 20 in total) were scanned on four 3 T magnetic resonance (MR) systems from four sites and three vendors (Siemens, General Electric, and Phillips). Two traveling volunteers (3 knees) scanned at all 4 sites at baseline and 6-month follow-up. Data was transferred to one site for centralized processing. Coefficients of variation (CVs) were calculated to evaluate reproducibility.

RESULTS

For baseline 2D MESE T2 measures, average CV were 0.37-2.45% (intra-site) and 5.96% (inter-site) for phantoms, and 3.15-8.49% (intra-site) and 14.16% (inter-site) for volunteers. For longitudinal phantom data, intra-site CVs were 1.42-3.48% for 3D MAPSS T1ρ, 1.77-3.56% for 3D MAPSS T2, and 1.02-2.54% for 2D MESE T2. For the longitudinal volunteer data, the intra-site CVs were 2.60-4.86% for 3D MAPSS T1ρ, 3.33-7.25% for 3D MAPSS T2, and 3.11-8.77% for 2D MESE T2.

CONCLUSION

This study demonstrated excellent intra-site reproducibility of 2D MESE T2 imaging, while its inter-site variation was slightly higher than 3D MAPSS T2 imaging (10.06% as previously reported). This study also showed excellent reproducibility of longitudinal T1ρ and T2 cartilage quantification, in a multi-vendor multi-site setting for both product 2D MESE T2 and 3D MAPSS T1p/T2 research sequences.

A148 IMPACT OF EXAMINATION UNDER ANESTHESIA PRIOR TO ANTI-TUMOR NECROSIS FACTOR THERAPY ON FISTULA HEALING FOR PERIANAL CROHN’S DISEASE PATIENTS: A COMPARATIVE COHORT STUDY

Background

Current guidelines recommend a combined approach consisting of an examination under anesthesia (EUA) and anti-TNF therapy for perianal Crohn’s Disease (PCD). However, the impact of this approach on fistula healing and long-term outcomes is unknown.

Aims

To assess the effect of EUA on fistula healing and long term outcomes in patients with perianal Crohn’s disese who are treated with anti-TNF therapy.

Methods

We performed a retrospective, single-center, comparative cohort study between 2009 and 2019. We compared patients with PCD who received EUA prior to anti-TNF therapy (combined therapy) to anti-TNF therapy alone. Our primary outcome was fistula closure by clinical assessment. Secondary outcomes included subsequent local surgery and fecal diversion. Logistic regression and multivariable cox-proportional hazard models adjusted for abscesses, concomitant immunomodulators, and time to anti-TNF initiation were performed.

Results

A total of 155 patients underwent 188 distinct anti-TNF starts: 66 (35%) after an EUA. Patients who underwent an EUA prior to anti-TNF therapy were more likely to have an abscess (50% vs. 15%; p < 0.001) and concomitant immunomodulator usage (64% vs. 50%; p = 0.07). Otherwise, there were no differences between cohorts in age, smoking status, disease duration, and location of luminal disease. There were no significant differences in fistula closure at 3, 6, or 12 months between cohorts overall (Table 1). The results remained consistent in sensitivity analyses that excluded patients with abscesses and prior biologic treatment failure. The results were also similar when defining the combined therapy group as those with setons. After a median follow-up of 4.6 years (IQR, 5.95) patients who underwent an EUA prior to anti-TNF therapy were more likely to require a subsequent EUA (aHR 2.2; 95% CI, 1.3–3.6) (Figure 1) but not fecal diversion (aHR 1.3; 95% CI, 0.45–3.9).

Conclusions

In this single center study, combined therapy (EUA prior to anti-TNF therapy) was not associated with improved clinical outcomes compared with anti-TNF therapy alone. These findings suggest that EUA may not be necessary in every patient with PCD prior to initiation of anti-TNF therapy. Future prospective studies that control for fistula complexity are warranted.

Table 1: Unadjusted rates of fistula closure after anti-TNF therapy comparing patients with and without an exam under anesthesia

Funding Agencies

University of Ottawa Department of Medicine

A159 ANTI-TUMOR NECROSIS FACTOR THERAPY PERSISTENCE IN PATIENTS WITH PERIANAL CROHN’S DISEASE AND LUMINAL CROHN’S DISEASE: A COMPARATIVE COHORT STUDY

Background

Anti-tumor necrosis factor therapy has revolutionized the management of Crohn’s disease. Despite its effectiveness, a substantial proportion of patients discontinue therapy over time. Evaluating drug persistence rates reveals a real-world pattern of biologic use. Perianal Crohn’s disease (PCD) is considered one of the most difficult phenotypes of Crohn’s disease (CD) to treat. Therefore, we hypothesized that patients with PCD have a shorter biologic persistence time due to refractory disease.

Aims

Our aim is to compare drug persistence rates of anti-TNF therapy between PCD and LCD patients.

Methods

We performed a retrospective, comparative cohort study at a tertiary care center between Nov 2019 and July 2020. Patients with CD were identified by our institutional data-base, using the ICD-10 code K50.90. A longitudinal chart review determine anti-TNF utilization and classified patients based on luminal CD only [LCD] or PCD. Patients with PCD were matched (1:1) to patients with LCD based on sex, age, and year of first anti-TNF initiation within 5 years. Time to discontinuation of anti-TNF therapy was estimated by Kaplan-Meier methods and compared between groups by Log-rank test.

Results

A total of 142 patients with PCD (55% male, 38.7 ± 13.7 years old at anti-TNF start) were matched to 142 patients with LCD (55% male, 38.7 ± 14.0 years old at anti-TNF start). The initial treatments included infliximab (67.6% vs. 57.7%) and adalimumab (32.4% vs. 42.3%) for patients with PCD and LCD respectively. Concomitant immunomodulator were used in 61.3% of patients with PCD and 54.9% of patients with LCD. The cumulative persistence of the initial anti-TNF therapy was similar between cohorts (Log rank, p = 0.633; Figure 1): mean time to discontinuation was 27.7 ± 26.8 months for patients with PCD and 26.5 ± 23.0 months for patients with LCD. The reasons for treatment discontinuation included: refractory disease (19% vs. 16%), anti-drug antibodies (6% vs. 12%), and side effects (12.7% vs. 16.2%) in patients PCD and LCD respectively. Of the patients who discontinued their first anti-TNF therapy, 36 patients (55.4%) with PCD and 42 patients (60.9%) with LCD were treated with a second anti-TNF therapy. Discontinuation of the second-line anti-TNF therapy occurred in 18 patients (50%) with PCD and 18 patients (42.9%) with LCD: mean time to discontinuation was 17.3 ± 14.3 months and 27.8 ± 28.8 months respectively.

Conclusions

In this single-center, observational study a substantial percentage of patients discontinue anti-TNF therapy overtime, and there does not appear to be a difference between patients with PCD and LCD.

Funding Agencies

None

P822Statin treatment in symptomatic patients with non-obstructive coronary artery disease reduces the risk of all-cause mortality

Introduction

Symptomatic patients with non-obstructive coronary artery disease (NOCAD; stenosis >0% <50%) have a worse prognosis and an increased risk for all-cause mortality compared with age-matched controls. Currently, treatment of these patients is empiric, and secondary preventive measures are less often implemented. The goal of the study was to examine whether statin prescription has an impact on all-cause mortality in symptomatic NOCAD patients, and which factors influence statin prescription in patients with NOCAD.

Methods

We examined 4039 symptomatic patients who presented either with stable angina (SA) or an acute coronary syndrome (ACS) who underwent coronary angiography; 1582 had angiographically normal coronary arteries, 2457 had minimal disease (NOCAD). The comparison group consisted of 2998 patients with stable obstructive CAD (stenosis ≥50%). Patients had at least one lipid panel tested between April 1, 2010 to March 31, 2014. We examined the rate of statin prescription amongst the groups, as well as predictors of all-cause mortality and statin treatment.

Results

Symptomatic patients with NOCAD are less likely to receive statin therapy (60.4%) compared to patients with obstructive CAD (87.3%). After one, three and five year(s), LDL levels in NOCAD patients are higher than in CAD patients (2.21±0.88mmol/l vs. 1.84mmol/l±0.77mmol/l after 1 year). Statin treatment was associated with a significantly lower risk of all-cause mortality in NOCAD (HR 0.64 (0.44–0.95)), as well as in CAD (HR 0.44 (0.31–0.62)), but not in patients with normal coronaries HR 0.55 (0.27–1.15)). Sex, age and the presence of other cardiovascular risk factors influenced the prescription of statin therapy in the first 5 years after initial diagnosis of NOCAD- older patients with diabetes and hypertension were more likely to receive statin therapy. Women received statin therapy to a lower percentage than men in the NOCAD group (year 1: men 62.9% vs, women 56.9%; p=0.003). No effect of cardiovascular risk factors, age or sex on statin prescription was seen in the CAD group or patients with normal coronaries.

Conclusion

Statin therapy reduces the risk of all-cause mortality in symptomatic patients with NOCAD. In spite of this benefit, patients with NOCAD, and especially women, are less likely to receive secondary-preventive statin therapy.

Waist circumference at five common measurement sites in normal weight and overweight adults: which site is most optimal?

The aim of this study was to determine (i) if adults would measure their own waist circumference (WC), (ii) which WC site(s) are the most intuitive and easy to measure and (iii) if measurement accuracy and association between WC and blood pressure differs across five measurement sites. Participants (n = 198) measured their WC first with no instruction and then using visual instructions for the iliac crest, last rib, midpoint, minimal waist and umbilicus. Without instruction, men most commonly measured their WC at the umbilicus and iliac crest, while women measured their WC at the umbilicus and minimal WC. Both men and women reported the minimal waist and umbilicus to be moderately easier to self-measure compared to the other sites (P < 0.05). Prevalence of abdominal obesity varied significantly by gender and measurement site, especially for females (normal weight: 0-18%; overweight: 51-79%). Measurement site did not influence accuracy of WC self-measurement or the association between WC and blood pressure (P > 0.05). A universal WC landmark is needed. From these results, there does not appear to be a clear clinical advantage in terms of blood pressure or practical advantage of measuring one WC site over another. However, the umbilicus may be the most intuitive and easy to measure.

Cancer referral and treatment activity 2010-2015: a population-based study from Vancouver Island

INTRODUCTION

The years since 2005 have seen major changes in cancer treatment and significant increases in the number of anticancer drugs available. However, there are relatively few published data to reflect how those changes are affecting the activity and workload of oncology services. To explore the effects of those changes, we reviewed the population-based cancer treatment activity on Vancouver Island for the period 2010-2015.

METHODS

Information about new patient referrals, radiation courses, new chemotherapy cycles commenced, total intravenous (IV) chemotherapy treatment visits, and pharmacy activity for oral anticancer drug prescriptions was obtained from BC Cancer Agency databases.

RESULTS

During the 5-year study period, the Vancouver Island population increased by 2.8% and the number of new referrals to the BC Cancer Agency increased by 17.7%. The overall number of radiation courses increased by 6.1%. In contrast, IV chemotherapy activity increased by 52.1% for new courses commenced and by 62% for total IV chemotherapy attendances. Oral anticancer drug prescriptions rose by 22.9% during the 5-year period.

CONCLUSIONS

Our study documents substantial recent increases in cancer therapy activity in terms of patient referrals and particularly IV chemotherapy and oral anticancer therapy. The data reported here could be of value in planning for future care provision.

A comparative evaluation of five hazard screening tools

An increasing number of hazard assessment tools and approaches are being used in the marketplace as a means to differentiate products and ingredients with lower versus higher hazards or to certify what some call greener chemical ingredients in consumer products. Some leading retailers have established policies for product manufacturers and their suppliers to disclose chemical ingredients and their related hazard characteristics often specifying what tools to use. To date, no data exists that show a tool's reliability to provide consistent, credible screening-level hazard scores that can inform greener product selection. We conducted a small pilot study to understand and compare the hazard scoring of several hazard screening tools to determine if hazard and toxicity profiles for chemicals differ. Seven chemicals were selected that represent both natural and man-made chemistries as well as a range of toxicological activity. We conducted the assessments according to each tool provider's guidelines, which included factors such as endpoints, weighting preferences, sources of information, and treatment of data gaps. The results indicate the tools varied in the level of discrimination seen in the scores for these 7 chemicals and that tool classifications of the same chemical varied widely between the tools, ranging from little or no hazard or toxicity to very high hazard or toxicity. The results also highlight the need for transparency in describing the basis for the tool's hazard scores and suggest possible enhancements. Based on this pilot study, tools should not be generalized to fit all situations because their evaluations are context-specific. Before choosing a tool or approach, it is critical that the assessment rationale be clearly defined and matches the selected tool or approach. Integr Environ Assess Manag 2017;13:139-154. © 2016 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC.

Adaptability of structured forms for CSII initiation in patients with type 2 diabetes the Getting2Goal(SM) concept

BACKGROUND

The goal is to assess the usability and satisfaction of implementing the Getting2Goal(SM) protocol by physicians transitioning patients with type 2 diabetes (T2DM) from multiple daily injections (MDI) to continuous subcutaneous insulin infusion (CSII).

METHODS

T2DM patients from three diabetes clinics were switched from MDI to CSII. Physicians used the Getting2Goal type 2 pumping protocol to prescribe and manage insulin pump therapy for T2DM. Surveys were conducted in which the physicians rated their feedback related to acceptability of the Getting2Goal on a 5-point Likert scale.

RESULTS

17 patients with T2DM were switched from MDI to CSII treatment. Mean (±standard deviation) age was 61.2 ± 7.7 (46-77) years, weight was 91.4 ± 21 (66-147) kg, BMI was 31.9 ± 7.6, A1C was 9.2 ± 1.4 % (7.2-12.3) and TDD on MDI was 109.1 ± 53.1 units. Surveys completed by physicians indicated Getting2Goal type 2 pumping protocol to be more efficient, time saving, and structured compared to their current processes. In addition, the primarily prescribed TDD on pump was 98.1 ± 50.0 units and the TDD at first download was 81.4 ± 36.4 units, representing a 25.4 % reduction in TDD At first download. The percentage of all blood glucose readings below 70 mg/dL was also very low.

CONCLUSIONS

The data indicate Getting2Goal materials as a standard approach that is simple and efficient to initiate pump therapy for T2DM. At the same time, it is safe and a useful tool for physicians that are starting to prescribe pump therapy for T2DM.

A review of 1000 referrals to Walsall's hospital eye service

BACKGROUND

Referrals to ophthalmology are predominantly made from general practitioners (GPs) and optometrists. These two groups of referrers receive differing types and levels of training and are equipped with different instrumentation. The purpose of this study was to determine whether the quality of referrals to the hospital eye service (HES) differs between GPs and optometrists in Walsall.

METHODS

Referrals into the HES were identified from Q1 2014 retrospectively until 1000 notes had been reached. Each record was scrutinized using a standard template. Data were analysed and summary statistics produced including positive predictive values and interobserver agreement.

RESULTS

We achieved our target of auditing 1000 records. The false-positive rate (patients being discharged from HES with a 'normal vision' diagnosis) was 7.7% of referrals from GPs and 6.2% of referrals from optometrists. Concordance between referred condition and diagnosed condition at HES between optometrists and ophthalmologists was 76.1%, and between GPs and ophthalmologists was 67.2%.

CONCLUSIONS

In view of findings from this study, it is important for commissioners in the new reconfigured National Health Service to ensure that enhanced ophthalmic services are commissioned only on the basis of hard evidence sourced from local data rather than opinion or on data from another geographical area.

Modification of human islet preparation: an effective approach to improve graft outcome after islet transplantation?

Revascularisation of transplanted islets is an essential prerequisite for graft survival and function. However, current islet isolation procedures deprive the islets of endothelial tubulets. This may have a detrimental effect on the revascularisation process of islets following transplantation. We hypothesise that modification of the isolation procedure that preserves islet endothelial vessels may improve the islet revascularisation process following transplantation. Here, we present a modified islet isolation method by which a substantial amount of endothelial cells still attached to the islets could be preserved. The islets with preserved endothelial cells isolated by this method were revascularised within 3 days, not observed in islets isolated by standard methods. Further, we observed that grafts of islets isolated by standard methods had more patches of dead tissue than islet grafts obtained by the modified method, indicating that attached endothelial cells may play an important role in the islet revascularisation process and potentially help to improve the transplantation outcome.

Involvement of interleukin-1 in the differentiation-inducing activity of tumor necrosis factor-alpha on a murine myeloid leukemia (WEHI-3B JCS)

We have shown previously that tumor necrosis factor-alpha (TNF-alpha) inhibits the growth and induces the differentiation of a murine myelomonocytic leukemia (WEHI-3B JCS cells) into macrophage-like cells. In this study, using reverse transcription polymerase chain reaction, we found that both endogenous interleukin-1 alpha and beta (IL-1 alpha, IL-1 beta) mRNA were up-regulated upon TNF-alpha induction. Exogenous IL-1 alpha and IL-1 beta also inhibited the growth as well as induced the differentiation of JCS cells, with IL-1 beta exerting a greater growth-inhibitory effect. Neutralizing anti-IL-1 alpha, anti-IL-1 beta and anti-TNF-alpha antibodies were further used to elucidate the role of IL-1 alpha, IL-1 beta and TNF-alpha in JCS cell differentiation. The results show that the IL-1 alpha-induced monocytic differentiation of JCS cells was effectively blocked by anti-IL-1 beta as well as anti-IL-1 beta antibodies and to a lesser extent by anti-TNF-alpha antibody. In contrast, the differentiation-inducing effect of IL-1 beta on JCS cells was only blocked by anti-IL-1 beta antibody but not by anti-IL-1 alpha or anti-TNF-alpha antibody. Finally, the TNF-alpha-induced monocytic differentiation of JCS cells was significantly blocked by anti-TNF-alpha and to a lesser extent by anti-IL-1 alpha and anti-IL-1 beta antibodies. Collectively, our results suggest that IL-1 beta alone may directly trigger JCS cell differentiation whereas the differentiation-inducing effect of IL-1 alpha may be via the endogenous production of IL-1 beta and/or TNF-alpha. In addition, IL-1 alpha and IL-1 beta may be involved, at least in part, in TNF-alpha-induced monocytic differentiation of the JCS leukemia cells.

CD59 efficiently protects human NT2-N neurons against complement-mediated damage

The complement regulatory protein CD59 controls cell survival by the inhibition of C5b-9 formation on the cell membrane. Loss of CD59 increases the susceptibility of cells to complement-mediated damage and lysis. Deposition of IgM can induce complement activation with subsequent cell death. We have previously demonstrated the presence of CD59 on human NT2-N neurons. In this study, we investigated the functional role of CD59 for NT2-N cell survival after IgM-mediated complement activation. Complement activation was induced on NT2-N neurons with human serum following incubation with the IgM monoclonal antibody A2B5 reacting with a neuronal cell membrane epitope. Deposition of C1q and C5b-9 was detected on the cell membrane and sC5b-9 in the culture supernatant. Specific inhibition of complement was obtained by the C3 inhibitor compstatin, and by anti-C5/C5a MoAb. CD59 was blocked by the MoAb BRIC 229. Membrane damage of propidium iodide-stained NT2-N cells was confirmed by immunofluorescence microscopy and degeneration of neuronal processes was shown with crystal violet staining. A2B5, but not the irrelevant control IgM antibody, induced complement activation on NT2-N neurons after incubation with a human serum, as detected by the deposition of C1q. A marked membrane deposition of C5b-9 on NT2-N neurons with accompanying cell death and axonal degeneration was found after the blocking of CD59 with MoAb BRIC 229 but not with an isotype-matched control antibody. Compstatin and anti-C5 monoclonal antibodies which blocked C5 activation efficiently inhibited complement activation. In conclusion, CD59 is essential for protecting human NT2-N neurons against complement-mediated damage, which is known to occur in a number of clinical conditions including stroke.

Growth, compatible solute and salt accumulation of five mycorrhizal fungal species grown over a range of NaCl concentrations

The oil sand industry in northeastern Alberta produces vast areas of severely disturbed land. The sodicity of these anthropic soils is one of the principal constraints that impede their revegetation. Previous in vitro studies have shown that the ectomycorrhizal fungi Laccaria bicolor (Maire) Orton UAMH 8232 and Hebeloma crustuliniforme (Bull) Quel. UAMH 5247 have certain salt-resistant traits and thus are candidate species for the inoculation of tree seedlings to be outplanted on salt-affected soil. In this study, the in vitro development of these fungi was compared to that of three mycorrhizal fungi [Suillus tomentosus (Kauff.) Sing., Snell and Dick; Hymenoscyphus sp. and Phialocephala sp.] isolated from a sodic site created by Syncrude Canada Ltd. Their growth, osmotica and Na/Cl contents were assessed over a range (0, 50, 100, 200 mM) of NaCl concentrations. After 21 days, the two ascomycetes (Hymenoscyphus sp. and Phialocephala sp.) were shown to be more resistant to the NaCl treatments than the three basidiomycete species. Of the basidiomycetes, L. bicolor was the most sensitive to NaCl stress, while H. crustuliniforme showed greater water stress resistance, and the S. tomentosus isolate exhibited greater Na and Cl filtering capacities and had a better biomass yield over the NaCl gradient tested. Both ascomycetes used mechanisms other than carbohydrate accumulation to palliate NaCl stress. While the Hymenoscyphus isolate accumulated proline in response to NaCl treatments, the darker Phialocephala isolate may have used compounds such as melanin. The basidiomycete species accumulated mainly mannitol and/or proline in response to increasing concentrations of NaCl.

Early growth response of container-grown selected woody boreal seedlings in amended composite tailings and tailings sand

Successful reclamation of saline-alkaline sites may be enhanced by revegetating with species that are tolerant to factors that limit normal plant growth. Boreal woody plants tested in this study have shown promise for use in saline habitats. This study was conducted to assess the effects of amendment treatments (peat, pulp waste, agriboost, a combination of pulp waste and fly ash, and mineral fertilizer) on the early growth of three hybrid poplar clones and three coniferous species. Twelve-week and 18-week container-grown hybrid poplar clones and coniferous species, respectively, were monitored for 12 weeks in pot culture in both composite tailings (CTs) and tailings sand (TS) materials obtained from the oil sands plant, Syncrude Canada Ltd., Ft. McMurray, Alberta. These substrates with low nutrients, organic matter, and water-holding capacities, were amended with different organic materials at different rates. Growth, as assessed by the volume increment in both substrates, was generally better for the first 6 weeks than for the last 6 weeks. Growth was reduced during the last 6 weeks due to nutrient depletion over time in these impoverished substrates. Overall, for both substrates, the mineral fertilizer, 20%, 40% and 60% peat were the best amendments treatments for poplar clones with NM-6 being the most productive clone. For coniferous species, 20% and 40% pulp or peat appear to be the best amendment treatments, with lodgepole pine being the most productive species. The inflexion point of the regression functions were found around 30% rate of the amendment materials. The results also indicated that peat and pulp waste were the best amendment treatments for both hybrid poplars and coniferous species whereas the agriboost and mix (combination of pulp waste and fly ash) were the worst.

The quantitative role of alternative pathway amplification in classical pathway induced terminal complement activation

Complement activation with formation of biologically potent mediators like C5a and the terminal C5b-9 complex (TCC) contributes essentially to development of inflammation and tissue damage in a number of autoimmune and inflammatory conditions. A particular role for complement in the ischaemia/reperfusion injury of the heart, skeletal muscle, central nervous system, intestine and kidney has been suggested from animal studies. Previous experiments in C3 and C4 knockout mice suggested an important role of the classical or lectin pathway in initiation of complement activation during intestinal ischaemia/reperfusion injury while later use of factor D knockout mice showed the alternative pathway to be critically involved. We hypothesized that alternative pathway amplification might play a more critical role in classical pathway-induced C5 activation than previously recognized and used pathway-selective inhibitory mAbs to further elucidate the role of the alternative pathway. Here we demonstrate that selective blockade of the alternative pathway by neutralizing factor D in human serum diluted 1 : 2 with mAb 166-32 inhibited more than 80% of C5a and TCC formation induced by solid phase IgM and solid- and fluid-phase human aggregated IgG via the classical pathway. The findings emphasize the influence of alternative pathway amplification on the effect of initial classical pathway activation and the therapeutic potential of inhibiting the alternative pathway in clinical conditions with excessive and uncontrolled complement activation.

Evaluation of the Capability of Aggregated Oil Sands Mine Tailings: Biological Indicators

Abstract

An experiment was initiated in 1997 in northeast Alberta at the Syncrude Canada Ltd. Mildred Lake site to field test an innovative technique for reclamation of oil sand mine tailings. This technique was used to create an aggregated soil material from oil sand tailings. A plant community was successfully established on the soil material created by this technique. However, whether the site would be capable of supporting a self-sustainable ecosystem for the long-term remained a challenging issue. We evaluated the capability of these aggregated oil sand tailings by using biological indicators of the abundance and diversity of soil microbial biomass. Soil respiration rates and soil microbial biomass measurements were used to assess the abundance and activities of soil microbial communities. The ability of soil microbial biomass to utilize a diverse range of carbon substrates was used to assess the diversity of soil microbial communities. Soil biological activity increased with increasing growth of plant biomass and over time. Increasing the amount of peat moss or muskeg incorporated into the soil during reclamation resulted in higher organic carbon and nitrogen content and caused an increase in abundance and diversity of soil microbial biomass. These results indicate that measurements of soil respiration and substrate utilization by soil microbial communities may be used as biological indicators for assessing the capability of reclaimed soils.

Introduction

A critical component in the reclamation of oil sand tailings is to create soil materials conducive to the growth of soil microorganisms and, as a result, to stimulate the soil microbial biomass mediated nutrient cycling process following initial reclamation. Soil organic carbon dynamics is at the centre of these processes. Soil microbial biomass is largely responsible for the decomposition of soil organic matter and litters that contribute to soil nutrient pools through mineralization. Additionally, certain soil microorganisms form symbiotic associations (mycorrhizae, nodules) with plants and contribute to the overall success of plant growth. Thus the success of planting for reclamation purposes is affected by, and may be contingent upon, the quality and quantity of soil microbial communities and their activities.

This paper presents the use of a few measurements of soil microbial activities as biological indicators for evaluating the capability of reclaimed soil.

Materials and Methods

Field Site

The site, located at Syncrude Canada Ltd. Mildred Lake in northeastern Alberta, was established in 1997. Composite tailings (CT) were used as a sub-material. Five treatments were used for the top 20 cm layer. The composite tailings, amended with various amounts of peat moss, were aggregated using an aggregation technology(1). The control consisted of standard reclamation material (RM) placed over the CT base. The properties of the materials used on this site, and the treatments used, are described in Table 1.

Each of the five treatments was replicated four times. A total of 20 (10 m by 10 m) plots arranged in four blocks were set up as a randomized complete block design. After the site was established, the following tree/shrub seedlings were transplanted:

Pre-neutralization of C5a-mediated effects by the monoclonal antibody 137-26 reacting with the C5a moiety of native C5 without preventing C5 cleavage

Complement C5a is aetiologically linked to inflammatory tissue damage in conditions like septicaemia, immune complex diseases and ischaemia-reperfusion injury. We here describe a monoclonal antibody (mAb), 137-26, that binds to the C5a moiety of human C5 and neutralizes the effects of C5a without interfering with C5 cleavage and the subsequent formation of lytic C5b-9 complex. Mouse anti-human C5 mAbs were generated and the reactivity with C5 and C5a was detected by ELISA and surface plasmon resonance. The inhibition of C5a binding to C5a receptor was studied using a radioligand binding assay. The effects of the antibody on C5a functions were examined using isolated neutrophils and a novel human whole blood model of inflammation. Haemolytic assays were used to study the effect on complement-mediated lysis. mAb 137-26 reacted with both solid- and solution-phase C5 and C5a in a dose-dependent manner with high affinity. The antibody competed C5a binding to C5a receptor and inhibited C5a-mediated chemotaxis of neutrophils. Furthermore, the antibody effectively abrogated complement-dependent E. coli-induced CD11b up-regulation and oxidative burst in neutrophils of human whole blood. mAb 137-26 was more potent than a C5a receptor antagonist and a previously described anti-C5a antibody. mAb 137-26 did not inhibit complement-mediated lysis, nor did it activate complement itself. Together, mAb 137-26 binds both the C5a moiety of native C5 and free C5a, thereby effectively neutralizing the biological effects of C5a. The antibody may have therapeutic potential in inflammatory diseases where C5a inhibition combined with an operative lytic pathway of C5b-9 is particularly desired.

Involvement of tumor necrosis factor (TNF-α) in arsenic trioxide induced apoptotic cell death of murine myeloid leukemia cells

Arsenic trioxide (As(2)O(3)) has recently been shown to be effective to inhibit the growth and to induce apoptosis in acute promyelocytic leukemia (APL) but not in acute myeloid leukemia (AML) cells. Recently, we have isolated an As(2)O(3) sensitive subclone JCS-16 from the murine myeloid leukemia WEHI 3B (JCS). At the concentrations of 0.3-3 microM, As(2)O(3) induces a dose-dependent cytotoxicity and growth inhibition on the JCS-16 cells. As(2)O(3) also induces apoptotic cell death, as judged by the presence of apoptotic nuclei, at 6 h after treatment. Morphological differentiation was not observed in As(2)O(3) treated JCS cells. Neutralizing anti-TNF-alpha antibody was found to reduce the As(2)O(3)-mediated apoptotic cell death of JCS-16 cells. Growth inhibitory effect of As(2)O(3) was also reduced after the addition of anti-TNF-alpha. In addition, reverse transcription polymerase chain reaction (RT-PCR) and reverse northern blot analysis demonstrated that the expression of TNF receptor (TNF-R2), IL-4, and IL-4R was down-regulate at 1 h after As(2)O(3) treatment. The expression of TNF-alpha and TNF-R1 was not affected. Our results suggest that the autocrine action of TNF-alpha might play a role in As(2)O(3)-induced apoptotic cell death of JCS-16 leukemia cells.

Human serum-induced expression of E-selectin on porcine aortic endothelial cells in vitro is totally complement mediated

BACKGROUND

Whereas complement is a key mediator of hyperacute xenograft rejection, its role in acute vascular rejection (AVR) is a matter of controversy. AVR is associated with de novo synthesis of endothelial cell-derived inflammatory mediators, including the leukocyte-recruiting adhesion molecule E-selectin. Here we investigate the role and mechanism of complement in human serum-induced porcine endothelial cell activation.

METHODS

An in vitro xenotransplantation method was designed using porcine aortic endothelial cells stimulated with human serum in microculture wells. E-selectin expression was measured by cell-enzyme immunoassay. Complement inhibitors acting at different levels in the cascade were investigated for their effect on E-selectin expression.

RESULTS

E-selectin was strongly induced by normal human serum but not by heat-inactivated serum. Compstatin, a synthetic C3 inhibitor, markedly reduced human serum-induced E-selectin expression. Purified C1-inhibitor suppressed E-selectin induction completely, indicating activation through the classical or lectin pathway. Furthermore, a monoclonal antibody (mAb) that inhibits cleavage of C5 or another mAb that blocks the function of C7, completely inhibited the expression of serum-induced E-selectin, consistent with the terminal C5b-9 complement complex being the mediator of the endothelial cell activation. Inhibition of the alternative pathway using a novel antifactor D mAb did not reduce E-selectin expression.

CONCLUSION

Human serum-induced expression of porcine E-selectin is totally complement dependent, induced by a C1-inhibitor regulated pathway and mediated through the terminal complement complex. The data may have implications for therapeutic strategies, particularly of C1-inhibitor and anti-C5 mAb, to protect against endothelial cell activation and subsequent AVR of porcine xenografts.