A network approach to developing immuno-oncology combinations in Canada.

Immune checkpoint inhibitors have revolutionized care for many cancer indications, with considerable effort now being focused on increasing the rate, depth, and duration of patient response. One strategy is to combine immune strategies (for example, ctla-4 and PD-1/L1-directed agents) to harness additive or synergistic efficacy while minimizing toxicity. Despite encouraging results with such combinations in multiple tumour types, numerous clinical challenges remain, including a lack of biomarkers that reliably predict outcome, the emergence of therapeutic resistance, and optimal management of immune-related toxicities. Furthermore, the selection of ideal combinations from the myriad of immune, systemic, and locoregional therapies has yet to be determined. A longitudinal network-based approach could offer advantages in addressing those critical questions, including long-term follow-up of patients beyond individual trials. The molecular cancer registry Personalize My Treatment, managed by the Networks of Centres of Excellence nonprofit organization Exactis Innovation, is uniquely positioned to accelerate Canadian immuno-oncology (io) research efforts throughout its national network of cancer sites. To gain deeper insight into how a pan-Canadian network could advance research in io combinations, Exactis invited preeminent clinical and scientific advisors from across Canada to a roundtable event in November 2017. The present white paper captures the expert advice provided: leverage longitudinal patient data collection; facilitate network collaboration and assay harmonization; synergize with existing initiatives, networks, and biobanks; and develop an io combination trial based on Canadian discoveries.

Canadian consensus: oligoprogressive, pseudoprogressive, and oligometastatic non-small-cell lung cancer.

Background: Little evidence has been generated for how best to manage patients with non-small-cell lung cancer (nsclc) presenting with rarer clinical scenarios, including oligometastases, oligoprogression, and pseudoprogression. In each of those scenarios, oncologists have to consider how best to balance efficacy with quality of life, while maximizing the duration of each line of therapy and ensuring that patients are still eligible for later options, including clinical trial enrolment. Methods: An expert panel was convened to define the clinical questions. Using case-based presentations, consensus practice recommendations for each clinical scenario were generated through focused, evidence-based discussions. Results: Treatment strategies and best-practice or consensus recommendations are presented, with areas of consensus and areas of uncertainty identified. Conclusions: In each situation, treatment has to be tailored to suit the individual patient, but with the intent of extending and maximizing the use of each line of treatment, while keeping treatment options in reserve for later lines of therapy. Patient participation in clinical trials examining these issues should be encouraged.

Regional process redesign of lung cancer care: a learning health system pilot project.

BACKGROUND: The Ottawa Hospital (toh) defined delay to timely lung cancer care as a system design problem. Recognizing the patient need for an integrated journey and the need for dynamic alignment of providers, toh used a learning health system (lhs) vision to redesign regional diagnostic processes. A lhs is driven by feedback utilizing operational and clinical information to drive system optimization and innovation. An essential component of a lhs is a collaborative platform that provides connectivity across silos, organizations, and professions. METHODS: To operationalize a lhs, we developed the Ottawa Health Transformation Model (ohtm) as a consensus approach that addresses process barriers, resistance to change, and conflicting priorities. A regional Community of Practice (cop) was established to engage stakeholders, and a dedicated transformation team supported process improvements and implementation. RESULTS: The project operationalized the lung cancer diagnostic pathway and optimized patient flow from referral to initiation of treatment. Twelve major processes in referral, review, diagnostics, assessment, triage, and consult were redesigned. The Ottawa Hospital now provides a diagnosis to 80% of referrals within the provincial target of 28 days. The median patient journey from referral to initial treatment decreased by 48% from 92 to 47 days. CONCLUSIONS: The initiative optimized regional integration from referral to initial treatment. Use of a lhs lens enabled the creation of a system that is standardized to best practice and open to ongoing innovation. Continued transformation initiatives across the continuum of care are needed to incorporate best practice and optimize delivery systems for regional populations.

Liquid-liquid phase separation in mixed organic/inorganic single aqueous aerosol droplets.

Direct measurements of the phase separation relative humidity (RH) and morphology of aerosol particles consisting of liquid organic and aqueous inorganic domains are presented. Single droplets of mixed phase composition are captured in a gradient force optical trap, and the evolving size, refractive index (RI), and morphology are characterized by cavity-enhanced Raman spectroscopy. Starting at a RH above the phase separation RH, the trapped particle is dried to lower RH and the transition to a phase-separated structure is inferred from distinct changes in the spectroscopic fingerprint. In particular, the phase separation RHs of droplets composed of aqueous solutions of polyethylene glycol (PEG-400)/ammonium sulfate and a mixture of C6-diacids/ammonium sulfate are probed, inferring the RH from the RI of the droplet immediately prior to phase separation. The observed phase separation RHs occur at RH marginally higher (at most 4%) than reported in previous measurements made from studies of particles deposited on hydrophobic surfaces by brightfield imaging. Clear evidence for the formation of phase-separated droplets of core-shell morphology is observed, although partially engulfed structures can also be inferred to form. Transitions between the different spectroscopic signatures of phase separation suggest that fluctuations in morphology can occur. For droplets that are repeatedly cycled through the phase separation RH, the water activity at phase separation is found to be remarkably reproducible (within ±0.0013) and is the same for the 1-phase to 2-phase transition and the 2-phase to 1-phase transition. By contrast, larger variation between the water activities at phase separation is observed for different droplets (typically ±0.02).

Wnt signaling pathway pharmacogenetics in non-small cell lung cancer.

Wingless-type protein (Wnt)/ß-catenin pathway alterations in non-small cell lung cancer (NSCLC) are associated with poor prognosis and resistance. In 598 stage III-IV NSCLC patients receiving platinum-based chemotherapy at the MD Anderson Cancer Center (MDACC), we correlated survival with 441 host single-nucleotide polymorphisms (SNPs) in 50 Wnt pathway genes. We then assessed the most significant SNPs in 240 Mayo Clinic patients receiving platinum-based chemotherapy for advanced NSCLC, 127 MDACC patients receiving platinum-based adjuvant chemotherapy and 340 early stage MDACC patients undergoing surgery alone (cohorts 2-4). In multivariate analysis, survival correlates with SNPs for AXIN2 (rs11868547 and rs4541111, of which rs11868547 was assessed in cohorts 2-4), Wnt-5B (rs12819505), CXXC4 (rs4413407) and WIF-1 (rs10878232). Median survival was 19.7, 15.6 and 10.7 months for patients with 1, 2 and 3-5 unfavorable genotypes, respectively (P=3.8 × 10(-9)). Survival tree analysis classified patients into two groups (median survival time 11.3 vs 17.3 months, P=4.7 × 10(-8)). None of the SNPs achieved significance in cohorts 2-4; however, there was a trend in the same direction as cohort 1 for 3 of the SNPs. Using online databases, we found rs10878232 displayed expression quantitative trait loci correlation with the expression of LEMD3, a neighboring gene previously associated with NSCLC survival. In conclusion, results from cohort 1 provide further evidence for an important role for Wnt in NSCLC. Investigation of Wnt inhibitors in advanced NSCLC would be reasonable. Lack of an SNP association with outcome in cohorts 2-4 could be due to low statistical power, impact of patient heterogeneity or false-positive observations in cohort 1.

A new approach to determine vapour pressures and hygroscopicities of aqueous aerosols containing semi-volatile organic compounds.

We present a new approach to study the equilibrium gas-particle partitioning of volatile and semi-volatile organic components in aqueous aerosol, deriving a correlational analysis method that examines and interprets simultaneous and correlated fluctuations in particle size and composition. From this approach, changes in particle size driven by organic component evaporation can be clearly resolved from size changes driven by hygroscopicity and fluctuations in environmental conditions. The approach is used to interpret measurements of the evaporation of semi-volatile organic components from binary aqueous/organic aerosol and the hygroscopic growth of involatile inorganic aerosol. The measurements have been made by the aerosol optical tweezers technique, which allows the simultaneous retrieval of particle size and refractive index with high accuracy. We suggest that this approach will be particularly valuable for investigating the thermodynamic behaviour of mixed component aqueous aerosol and will allow the accurate derivation of solution phase equilibrium properties that are prone to large uncertainties when measurements are made simply of the change in particle size with gas phase relative humidity.

Ten-year experience of esophageal self-expanding metal stent insertion at a single institution.

Palliation of malignant dysphagia can be achieved using self-expanding metal stents (SEMS). This study was conceived to confirm that the insertion of SEMS improved patient symptoms without serious complications and to allow comparison with recent national data. Retrospective case note review of all patients receiving SEMS over a 10-year period between March 1999 and February 2009 was used in this study. There were 138 consecutive patients (50 female), median age of 75 (range 46-90) years, 122 (88.5%) had primary malignant disease of the esophagus or gastroesophageal junction. In total, 250 endoscopic examinations were carried out, with 200 interventional procedures, including the insertion of 156 SEMS. Before stenting, 74.2% of patients had a dysphagia score of 2-3. Following stent insertion, dysphagia scores improved to 0-1 in 90.3% of patients (P < 0.0001, Wilcoxon signed ranks). No complications were encountered in 61 (44%) patients. Chest pain was the most frequent difficulty, encountered in 50 (36%) patients. Tumor overgrowth occurred in 17 (12.3%) patients and food bolus obstruction was seen in 7% of patients. There were no esophageal perforations attributable to SEMS insertion. Overall 30-day mortality for those with esophago-gastric malignancy was 11.6% (16 patients), although the SEMS-related mortality was 2.2% (3 patients). Median survival from SEMS insertion was 3 (IQR 1.5-7) months. Patients requiring re-intervention for tumor overgrowth had a significantly longer median survival of 9.2 months (P= 0.001, log rank). SEMS were well tolerated with overall mortality and complication rates comparable to national data. For the longer survivors, re-intervention for recurrent dysphagia was not unusual.

Peptides specific for Mycobacterium avium subspecies paratuberculosis infection: diagnostic potential.

Mycobacterium avium subspecies paratuberculosis (Map) is the causative agent of Johne's disease (JD). Current serological diagnostic tests for JD are limited by their sensitivity when used in sub-clinical stages of the disease. Our objective was to identify peptides that mimic diagnostically important Map epitopes that might be incorporated into a new-generation JD diagnostic. Four peptides were isolated from a phage-displayed random peptide library by screening on antibodies derived from Map-infected goats. The peptides were recognised by antibodies from Map-infected goats but not by antibodies from uninfected goats. The peptides elicited immune responses in rabbits, which reacted strongly with bona fide Map antigens proving the peptides were true epitope mimics. To assess the diagnostic value a panel of goat sera was screened for reactivity's with peptides. The peptides were recognised by antibodies from a proportion of goats infected with Map compared with control animals with a diagnostic specificity of 100% and the sensitivity ranged from 50 to 75%. Combinations of any two peptides improved sensitivity 62.5-87.5% and 100% sensitivity was achieved with three of the four peptides in combination. These data suggest peptides representing diagnostically important Map epitopes could be incorporated into a sensitive diagnostic test.

Review: molecular pathogenesis of blood-brain barrier breakdown in acute brain injury.

Historically, the blood-brain barrier (BBB) was considered to be at the level of cerebral endothelium. Currently, the interaction of endothelium with other components of the vessel wall and with neurones and glial cells is considered to constitute a functional unit, termed the neurovascular unit that maintains cerebral homeostasis in steady states and brain injury. The emphasis of this review is on cerebral endothelium, the best-studied component of the neurovascular unit, and its permeability mechanisms in health and acute brain injury. Major advances have been made in unravelling the molecular structure of caveolae and tight junctions, both of which are components of the structural barrier to the entry of plasma proteins into brain. Time course studies suggest that caveolar changes precede junctional changes in acute brain injury. Additional factors modulating BBB permeability in acute brain injury are matrix metalloproteinases-2 and 9 and angiogenic factors, the most notable being vascular endothelial growth factor-A and angiopoietins (Ang) 1 and 2. Vascular endothelial growth factor-A and Ang2 have emerged as potent inducers of BBB breakdown while Ang1 is a potent anti-leakage factor. These factors have the potential to modulate permeability in acute brain injury and this is an area of ongoing research. Overall, a combination of haemodynamic, structural and molecular alterations affecting brain endothelium results in BBB breakdown in acute brain injury.

Nitrogen management is essential to prevent tropical oil palm plantations from causing ground-level ozone pollution.

More than half the world's rainforest has been lost to agriculture since the Industrial Revolution. Among the most widespread tropical crops is oil palm (Elaeis guineensis): global production now exceeds 35 million tonnes per year. In Malaysia, for example, 13% of land area is now oil palm plantation, compared with 1% in 1974. There are enormous pressures to increase palm oil production for food, domestic products, and, especially, biofuels. Greater use of palm oil for biofuel production is predicated on the assumption that palm oil is an "environmentally friendly" fuel feedstock. Here we show, using measurements and models, that oil palm plantations in Malaysia directly emit more oxides of nitrogen and volatile organic compounds than rainforest. These compounds lead to the production of ground-level ozone (O(3)), an air pollutant that damages human health, plants, and materials, reduces crop productivity, and has effects on the Earth's climate. Our measurements show that, at present, O(3) concentrations do not differ significantly over rainforest and adjacent oil palm plantation landscapes. However, our model calculations predict that if concentrations of oxides of nitrogen in Borneo are allowed to reach those currently seen over rural North America and Europe, ground-level O(3) concentrations will reach 100 parts per billion (10(9)) volume (ppbv) and exceed levels known to be harmful to human health. Our study provides an early warning of the urgent need to develop policies that manage nitrogen emissions if the detrimental effects of palm oil production on air quality and climate are to be avoided.

Expression of endothelial phosphorylated caveolin-1 is increased in brain injury.

AIMS: Increased endothelial caveolae leading to transcytosis of plasma proteins is associated with blood-brain barrier (BBB) breakdown and cerebral oedema in brain injury. Increased expression of caveolin-1alpha (Cav-1), an integral caveolar membrane protein, was reported in endothelium of arterioles and veins with BBB breakdown to fibronectin post injury. In this study the phosphorylation state of Cav-1 and its association with BBB breakdown was determined in the rat cortical cold injury model over a period of days 0.5-6 post lesion. METHODS: Expression of phosphorylated Cav-1 was determined by immunoblotting and dual labelling immunofluorescence for phosphorylated caveolin-1 and fibronectin, a marker of BBB breakdown. A phospho-specific monoclonal antibody that selectively recognizes only tyrosine 14-phosphorylated Cav-1 (PY14Cav-1) was used. RESULTS: Immunoblots showed constitutive expression of PY14Cav-1 in cortex of control rats and a significant increase in PY14Cav-1 expression at the lesion site up to day 4 post lesion. PY14Cav-1 immunostaining was observed in the endothelium of lesion vessels at days 0.5-4 post lesion, in neutrophils at days 0.5 and 2 and in macrophages at day 6 post lesion. Dual labelling showed that 100% of vessels with BBB breakdown to fibronectin showed endothelial PY14Cav-1 on day 0.5, the percentage decreasing to 62% on day 4. On day 6, none of the vessels showed endothelial phosphorylated Cav-1. CONCLUSIONS: The presence of phosphorylated Cav-1 in endothelium of vessels showing BBB breakdown suggests that phosphorylated Cav-1 signalling may be one of the factors associated with early BBB breakdown and brain oedema in brain injury.

Expression of methylation-related genes is associated with overall survival in patients with non-small cell lung cancer.

The abnormality of DNA methylation is involved in tumour progression, and thus has a modulating effect on clinical outcome of cancer patients. In this study, we measured the mRNA expression levels of three methylation-regulating genes (DNMT1, DNMT3b, and MBD2) in 148 tumour samples from patients with non-small cell lung cancer (NSCLC) using quantitative real-time polymerase chain reaction and then determined their prognostic values. Our data showed that the high level of DNMT1 expression was significantly associated with an increased risk of death in all NSCLC patients (hazard ratio (HR), 1.74; 95% confidence interval (95% CI), 1.04-2.90). However, the high level of DNMT3b expression was significantly associated with poor prognosis only in young patients (<65 years). The high level of MBD2 expression had a significantly reduced risk for death only in male patients and in squamous cell lung carcinoma (SQLC) patients. All three combination groups with DNMT1 and DNMT3b, DNMT1 and MBD2 or DNMT3b and MBD2 revealed significant combined effects in male patients and SQLC patients. Our results suggest that DNMT1, DNMT3b, and MBD2 may play important roles in modulating NSCLC patient survival and thus be useful for identifying NSCLC patients who would benefit most from aggressive therapy.

A long-term bacteriological and immunological study in Holstein-Friesian cattle experimentally infected with Mycobacterium avium subsp. paratuberculosis and necropsy culture results for Holstein-Friesian cattle, Merino sheep and Angora goats.

The aims were to longitudinally evaluate the interferon-gamma (IFN-gamma) test in comparison to faecal culture and the absorbed ELISA in a cattle infection model for Johne's disease and to determine the adult infection status, by necropsy and tissue culture, of sheep, goats and cattle infected as young animals. Clinical disease, faecal culture results and immunological responses for Merino sheep [Stewart, D.J., Vaughan, J.A., Stiles, P.L., Noske, P.J., Tizard, M.L.V., Prowse, S.J., Michalski, W.P., Butler, K.L., Jones, S.L., 2004. A long-term study in Merino sheep experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies. Vet. Microbiol. 104, 165-178] and Angora goats [Stewart, D.J., Vaughan, J.A., Stiles, P.L., Noske, P.J., Tizard, M.L.V., Prowse, S.J., Michalski, W.P., Butler, K.L., Jones, S.L., 2006. A long-term study in Angora goats experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies. Vet. Microbiol. 113, 13-24], in the same experiments as the Holstein-Friesian cattle, have been described. Two longitudinal experiments involving Holstein-Friesian cattle challenged with either bovine or ovine strains of Mycobacterium avium subsp. paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the IFN-gamma test and the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Cell-mediated (CMI) responses were substantially higher for the bovine Map strain during the 42-month period following dosing but then declined in the remaining 12 months. However, for the ovine Map challenge and control groups, CMI responses were not significantly different from each other. None of the cattle developed clinical disease and only one of the cattle in the bovine Map gut mucosal tissue challenged group was a persistent faecal shedder and also an ELISA antibody responder which developed after shedding commenced. Culture of tissues, following necropsy at the completion of the experiments, showed no evidence of infection in any of the challenged cattle and sheep for either the bovine or ovine Map strain in contrast to positive cultures for challenged goats in the same experiments. The tissues from the control cattle, sheep and goats were culture negative. The cattle were less susceptible to the bovine and ovine Map strains than goats and sheep with the goats being the least naturally resistant.

Angiogenic gene therapy in patients with nonrevascularizable ischemic heart disease: a phase 2 randomized, controlled trial of AdVEGF(121) (AdVEGF121) versus maximum medical treatment.

The demonstration that angiogenic growth factors can stimulate new blood vessel growth and restore perfusion in animal models of myocardial ischemia has led to the development of strategies designed for the local production of angiogenic growth factors in patients who are not candidates for conventional revascularization. The results of recent clinical trials of proangiogenesis gene therapy have been disappointing; however, significant limitations in experimental design, in particular in gene transfer strategies, preclude drawing definitive conclusions. In the REVASC study cardiac gene transfer was optimized by direct intramyocardial delivery of a replication-deficient adenovirus-containing vascular endothelial growth factor (AdVEGF121, 4 x 10(10) particle units (p.u.)). Sixty-seven patients with severe angina due to coronary artery disease and no conventional options for revascularization were randomized to AdVEGF121 gene transfer via mini-thoracotomy or continuation of maximal medical treatment. Exercise time to 1 mm ST-segment depression, the predefined primary end-point analysis, was significantly increased in the AdVEGF121 group compared to control at 26 weeks (P=0.026), but not at 12 weeks. As well, total exercise duration and time to moderate angina at weeks 12 and 26, and in angina symptoms as measured by the Canadian Cardiovascular Society Angina Class and Seattle Angina Questionnaire were all improved by VEGF gene transfer (all P-values at 12 and 26 weeks < or =0.001). However, if anything the results of nuclear perfusion imaging favored the control group, although the AdVEGF121 group achieved higher workloads. Overall there was no significant difference in adverse events between the two groups, despite the fact that procedure-related events were seen only in the thoracotomy group. Therefore, administration of AdVEGF121 by direct intramyocardial injections resulted in objective improvement in exercise-induced ischemia in patients with refractory ischemic heart disease.

The pattern of lymph node involvement influences outcome after extrapleural pneumonectomy for malignant mesothelioma.

OBJECTIVE: We sought to examine the distribution and prognostic implications of nodal metastasis in patients undergoing extrapleural pneumonectomy for malignant mesothelioma in a specialist center. METHODS: We have examined the lymphadenectomy specimens from 92 consecutive cases of malignant mesothelioma undergoing extrapleural pneumonectomy from September 1999 through February 2005 inclusive. Nodal stations (Naruke) were assigned to all nodes, and patients were staged according to the current International Union Against Cancer system. The status and number of nodes in each station were recorded, and results were correlated with the results of preoperative mediastinoscopic findings (n = 30) and survival. RESULTS: The nodal distribution was 48 N0, 9 N1, and 35 N2. Single and multistation nodal involvement was present in 20 and 24 cases, respectively. Among the patients undergoing mediastinoscopy, N2 disease after extrapleural pneumonectomy occurred in 10 (33%). Skip N2 metastasis was present in 10 (42%) cases. Positive N2 nodes inaccessible by mediastinoscopy were present in 17 (49%) cases. N2 metastasis was associated with reduced survival (P = .02), but there was no difference between N1 and N2 cases (P = .4). The number of positive nodes correlated with survival (P = .001), although the number of involved stations and their anatomic location did not. There was no difference in survival between skip N2 cases and either other N2 or N1 cases. CONCLUSIONS: The classical anatomic location is not as important as the scatter of nodal involvement. Every effort should be made to obtain biopsy specimens from as many stations as possible before undertaking extrapleural pneumonectomy for malignant mesothelioma.

Chronic systemic delivery of angiopoietin-2 reveals a possible independent angiogenic effect.

Angiopoietin-2 has been implicated in the angiogenic response; however, this response has been tied to the expression of VEGF, and an independent angiogenic role has yet to be described. In this report, we detail the generation of transgenic mice that conditionally express angiopoietin-2 in the liver, resulting in sustained increases in circulating levels. These animals survive gestation and present with several vascular abnormalities, including an increase in the diameter of myocardial coronary vessels and a reduction in the density of endocardial vessels. In the lung, prominent increases in vessel diameter were observed. These vascular remodeling changes occurred in the absence of any apparent increase in VEGF expression. Our results illustrate that chronic systemic delivery of angiopoietin-2 induces angiogenesis in the absence of increased VEGF expression and that angiopoietin-2 promotes myocardial coronary vessel remodeling.

The hallucinogenic herb Salvia divinorum and its active ingredient salvinorin A inhibit enteric cholinergic transmission in the guinea-pig ileum.

Salvia divinorum is a widespread hallucinogenic herb traditionally employed for divination, as well as a medicament for several disorders including disturbances of gastrointestinal motility. In the present study we evaluated the effect of a standardized extract from the leaves of S. divinorum (SDE) on enteric cholinergic transmission in the guinea-pig ileum. SDE reduced electrically evoked contractions without modifying the contractions elicited by exogenous acetylcholine, thus suggesting a prejunctional site of action. The inhibitory effect of SDE on twitch response was abolished by the opioid receptor antagonist naloxone and by the kappa-opioid antagonist nor-binaltorphimine, but not by naltrindole (a delta-opioid receptor antagonist), CTOP (a mu-opioid receptor antagonist), thioperamide (a H(3) receptor antagonist), yohimbine (an alpha(2)-receptor antagonist), methysergide (a 5-hydroxytryptamine receptor antagonist), N(G)-nitro-L-arginine methyl ester (an inhibitor of NO synthase) or apamin (a blocker of Ca(2+)-activated K(+) channels). Salvinorin A, the main active ingredient of S. divinorum, inhibited in a nor-binaltorphimine- and naloxone-sensitive manner electrically induced contractions. It is concluded that SDE depressed enteric cholinergic transmission likely through activation of kappa-opioid receptors and this may provide the pharmacological basis underlying its traditional antidiarrhoeal use. Salvinorin A might be the chemical ingredient responsible for this activity.

A long-term study in Angora goats experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies.

Two longitudinal experiments involving Angora goats challenged with either bovine or ovine strains of Mycobacterium avium subspecies paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the interferon-gamma (IFN-gamma) test and the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Persistent shedding, IFN-gamma production, seroconversion and clinical disease occurred earlier with the bovine Map gut mucosal tissue challenge inoculum than with cultured bacteria. The IFN-gamma responses of the gut mucosal tissue and bacterial challenge groups were substantially and consistently higher than those of the control group. The in vivo and cultured cattle strains were much more pathogenic for goats than the sheep strains with persistent faecal shedding, seroconversion and clinical disease occurring in the majority of bovine Map challenged goats. With the ovine Map, 3 goats developed persistent antibody responses but only one of these goats developed persistent faecal shedding and clinical disease. However, there was no significant difference between the IFN-gamma responses of the tissue challenged, bacterial challenged and control groups. Compared with sheep, the ELISA appeared to have higher sensitivity and the IFN-gamma test lower specificity.

Phase II study of troxacitabine (BCH-4556) in patients with advanced non-small-cell lung cancer.

Troxacitabine. a promising new L-nucleoside, inhibits DNA polymerase and leads to complete DNA chain termination. The National Cancer Institute of Canada Clinical Trials Group (NCIC-CTG) conducted a phase II study to assess the efficacy and toxicity of troxacitabine in untreated patients with advanced non-small-cell lung cancer (NSCLC). Previously untreated patients were eligible if they had inoperable stage IIIB or IV NSCLC, ECOG PS < or = 2, adequate hematology and biochemistry, and at least one bidimensionally measurable lesion. Patients with prior malignancy or brain metastases were excluded. Troxacitabine (10 mg/m(2)) was administered intravenously over 30 minutes every 3 weeks. Between June 1999 and May 2000, 17 eligible patients received treatment. Patient characteristics included: median age 64 years; female 41%; stage IV (94%); PS 0 (12%), 1 (59%), and 2 (29 %), 3 or more disease sites (59%). In 17 patients, there were 8 stable disease, 9 disease progression, and no objective responses. Median duration of stable disease was 3.6 months (range = 2.0-7.1). A total of 56 cycles were administered (median = 3), and 88% of patients received 90% or more of the planned dose intensity. The majority (82%) of patients experienced skin rash. Hematologic and biochemical toxicities, grade 3/4 (%) were: granulocytopenia (41), anemia (12), thrombocytopenia (6), and hyperglycemia (6). Troxacitabine appears to have little activity in NSCLC in the dose and schedule tested.