Publications by authors named "Brett Charlton"

The lysyl oxidase family represents a promising target in stromal targeting of solid tumors due to the importance of this family in crosslinking and stabilizing fibrillar collagens and its known role in tumor desmoplasia. Using small-molecule drug-design approaches, we generated and validated PXS-5505, a first-in-class highly selective and potent pan-lysyl oxidase inhibitor. We demonstrate in vitro and in vivo that pan-lysyl oxidase inhibition decreases chemotherapy-induced pancreatic tumor desmoplasia and stiffness, reduces cancer cell invasion and metastasis, improves tumor perfusion and enhances the efficacy of chemotherapy in the autochthonous genetically engineered KPC model, while also demonstrating antifibrotic effects in human patient-derived xenograft models of pancreatic cancer.

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Background: Mannitol is a mucoactive hyperosmotic agent used as add-on therapy in patients with cystic fibrosis (CF), administered twice-daily (BID) via a small, portable, breath-actuated dry-powder inhaler. This study was conducted to provide confirmatory evidence of mannitol's efficacy and safety in adults.

Methods: This multicenter, double-blind, randomized, parallel-group, controlled clinical trial recruited adults (aged ≥18 years) with CF, and forced expiratory volume in 1 second (FEV) 40-90% predicted.

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Abstract: There has been remarkable progress in the treatment of cystic fibrosis (CF) patients over the past 20 years. However, limitations of standard therapies have highlighted the need for a convenient alternative treatment to effectively target the pathophysiologic basis of CF-related disease by improving mucociliary clearance of airway secretions and consequently improve lung function and reduce respiratory exacerbations. Mannitol is an osmotic agent available as a dry powder, dispensed in a convenient disposable inhaler device for the treatment of adult patients with CF.

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Rationale: Bronchiectasis is characterised by excessive production of mucus and pulmonary exacerbations. Inhaled osmotic agents may enhance mucociliary clearance, but few long-term clinical trials have been conducted.

Objectives: To determine the impact of inhaled mannitol on exacerbation rates in patients with non-cystic fibrosis (CF) bronchiectasis.

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Introduction: Drug inhalation via a dry-powder inhaler (DPI) is a convenient, time efficient alternative to nebulizers in the treatment of cystic fibrosis (CF) or non-CF bronchiectasis. Efficient drug administration via DPIs depends on the device resistance and adequate (≥45L/min) inspiratory flows and volumes generated by individuals. Drypowder mannitol is delivered using a RS01 breath-actuated device developed by Plastiape, for Pharmaxis.

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Introduction: Drug inhalation via a dry-powder inhaler (DPI) is a convenient, time efficient alternative to nebulizers in the treatment of cystic fibrosis (CF). Efficient drug administration via DPIs depends on the device resistance and adequate (≥ 45L/min) inspiratory flows and volumes generated by individuals. Dry-powder mannitol is delivered using a RS01 breath-actuated device developed by Plastiape, for Pharmaxis.

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Background: Inhaled dry powder mannitol enhanced mucus clearance and improved quality of life over 2 weeks in non-cystic fibrosis bronchiectasis. This study's objective was to investigate the efficacy and safety of dry powder mannitol over 12 weeks.

Methods: Patients with bronchiectasis confirmed by high-resolution CT (HRCT) scan, aged 15 to 80 years, with FEV1≥50% predicted and ≥1 L participated in a randomized, placebo-controlled, double-blind study.

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Background: To evaluate safety and efficacy of inhaled mannitol treatment in subgroups of a large global CF population.

Methods: Data were pooled from two multicentre, double-blind, randomised, controlled, parallel group phase III studies in which 600 patients inhaled either mannitol (400 mg) or control (mannitol 50 mg) twice a day for 26 weeks.

Results: Both the mean absolute change in FEV(1) (mL) and relative change in FEV(1) by % predicted from baseline for mannitol (400 mg) versus control were statistically significant (73.

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Rationale: New treatment strategies are needed to improve airway clearance and reduce the morbidity and the time burden associated with cystic fibrosis (CF).

Objectives: To determine whether long-term treatment with inhaled mannitol, an osmotic agent, improves lung function and morbidity.

Methods: Double-blind, randomized, controlled trial of inhaled mannitol, 400 mg twice a day (n = 192, "treated" group) or 50 mg twice a day (n = 126, "control" group) for 26 weeks, followed by 26 weeks of open-label treatment.

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Background: Cystic fibrosis (CF) is characterised by impaired mucociliary clearance (MCC), chronic inflammation and infection, and progressively deteriorating lung function. Inhaled mannitol (Bronchitol) has been shown to increase MCC and cough clearance and FEV(1) in CF patients, contributing to better lung hygiene and consequently a slower decline in lung function. This study was designed to determine the dose relationship of mannitol treatment and improvement in FEV(1) and FVC as well as safety.

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Background: The airway mucus in patients with cystic fibrosis (CF) is dehydrated and adhesive and accumulates in the airways, resulting in chronic inflammation, infection, and progressive loss of lung function. Inhaled mannitol improves mucus clearance and, when administered over 2 weeks, it improves lung function in CF (Jaques et al. Chest.

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Background: Asthma can be difficult to diagnose, but bronchial provocation with methacholine, exercise or mannitol is helpful when used to identify bronchial hyperresponsiveness (BHR), a key feature of the disease. The utility of these tests in subjects with signs and symptoms of asthma but without a clear diagnosis has not been investigated. We investigated the sensitivity and specificity of mannitol to identify exercise-induced bronchoconstriction (EIB) as a manifestation of BHR; compared this with methacholine; and compared the sensitivity and specificity of mannitol and methacholine for a clinician diagnosis of asthma.

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Background: The airways in patients with cystic fibrosis (CF) are characterized by the accumulation of tenacious, dehydrated mucus that is a precursor for chronic infection, inflammation, and tissue destruction. The clearance of mucus is an integral component of daily therapy. Inhaled mannitol is an osmotic agent that increases the water content of the airway surface liquid, and improves the clearance of mucus with the potential to improve lung function and respiratory health.

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Background: Inhaled mannitol is a new bronchial provocation test (BPT) developed to improve portability and standardisation of osmotic challenge testing. Osmotic challenge tests have an advantage over the traditional methods of measuring airway hyperresponsiveness using methacholine as they demonstrate higher specificity to identify asthma and thus the need for treatment with inhaled corticosteroids (ICS). The safety and the efficacy of mannitol (M) as a BPT to measure airway hyperresponsiveness were compared to hypertonic (4.

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Despite evidence that both Fas and FasL can be expressed in pancreatic islets, there has been considerable controversy regarding the potential role of Fas signaling in autoimmune beta cell death. Using the HIPFasL model, we have been able to demonstrate that, in the presence of an inflammatory infiltrate, FasL-expressing beta cells are exquisitely sensitive to Fas-mediated apoptosis and that this can be blocked by preventing FasL-Fas interaction. This points to a highly important role of Fas-FasL interaction in autoimmune beta cell death.

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Type 1 diabetes occurs as a result of an autoimmune attack on the insulin-producing beta cells. Although CD8 T cells have been implicated both early and late in this process, the requirement for direct interaction between these cells and MHC class I on the beta cells has not been demonstrated. By using nonobese diabetic mice lacking beta cell class I expression, we show that both initiation and progression of insulitis proceeds unperturbed.

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Nonobese diabetic (NOD) mice transgenic for Fas ligand (FasL) on islet beta cells (HIPFasL mice) exhibit an accelerated diabetes distinct from the normal autoimmune diabetes of NOD mice. This study was undertaken to define the mechanism underlying accelerated diabetes development in HIPFasL mice. It was found that diabetes in HIPFasL mice is dependent on the NOD genetic background, as HIPFasL does not cause diabetes when crossed into other mice strains and is lymphocyte dependent, as it does not develop in HIPFasL(SCID) mice.

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