Layering vaccination with antibiotic therapy results in protection and clearance of Burkholderia pseudomallei in Balb/c mice.

Melioidosis is a disease that is difficult to treat due to the causative organism, Burkholderia pseudomallei being inherently antibiotic resistant and it having the ability to invade, survive, and replicate in an intracellular environment. Combination therapy approaches are routinely being evaluated in animal models with the aim of improving the level of protection and clearance of colonizing bacteria detected. In this study, a subunit vaccine layered with the antibiotic finafloxacin was evaluated in vivo against an inhalational infection with B. pseudomallei in Balb/c mice. Groups of mice vaccinated, infected, and euthanized at antibiotic initiation had a reduced bacterial load compared to those that had not been immunized. In addition, the subunit vaccine provided a synergistic effect when it was delivered with a CpG ODN and finafloxacin was initiated at 48 h post-challenge. Vaccination was also shown to improve the outcome, in a composite measure of survival and clearance. In summary, layering a subunit vaccine with the antibiotic finafloxacin is a promising therapeutic alternative for use in the treatment of B. pseudomallei infections.

British Society for Paediatric and Adolescent Dermatology assessment and support of mental health in children and young people with skin conditions: a multidisciplinary expert consensus statement and recommendations.

BACKGROUND: Psychological and mental health difficulties are common in children and young people (CYP) living with skin conditions and can have a profound impact on wellbeing. There is limited guidance on how best to assess and support the mental health of this population, who are at risk of poor health outcomes. OBJECTIVES: To provide consensus-based recommendations on the assessment and monitoring of and support for mental health difficulties in CYP with skin conditions (affecting the skin, hair and nails); to address practical clinical implementation questions relating to consensus guidance; and to provide audit and research recommendations. METHODS: This set of recommendations was developed with reference to the AGREE II instrument. A systematic review and literature appraisal was carried out. A multidisciplinary consensus group was convened, with two virtual panel meetings held: an initial meeting to discuss the scope of the study, to review the current evidence and to identify areas for development; and a second meeting to agree on the content and wording of the recommendations. Recommendations were then circulated to stakeholders, following which amendments were made and agreed by email. RESULTS: The expert panel achieved consensus on 11 recommendations for healthcare workers managing CYP with skin conditions. A new patient-completed history-taking aid ('You and Your Skin') was developed and is being piloted. CONCLUSIONS: The recommendations focus on improved mental health assessments for CYP presenting with a skin condition, with clinical guidance and suggested screening measures included. Information on accessing psychological support for CYP, when required, is given, and recommendations for staff training in mental health and neurodiversity provided. Embedding a psychosocial approach within services treating CYP with skin disease should ensure that CYP with psychological needs are able to be identified, listened to, supported and treated. This is likely to improve health outcomes.

Investigation of a combination therapy approach for the treatment of melioidosis.

The efficacy of finafloxacin as a component of a layered defense treatment regimen was determined in vitro and in vivo against an infection with Burkholderia pseudomallei. Doxycycline was down-selected from a panel of antibiotics evaluated in vitro and used in combination with finafloxacin in a Balb/c mouse model of inhalational melioidosis. When treatment was initiated at 24 h post-infection with B. pseudomallei, there were no differences in the level of protection offered by finafloxacin or doxycycline (as monotherapies) when compared to the combination therapy. There was evidence for improved bacterial control in the groups treated with finafloxacin (as monotherapies or in combination with doxycycline) when compared to mice treated with doxycycline. Survival comparisons of finafloxacin and doxycycline (as monotherapies) or in combination initiated at 36 h post-infection indicated that finafloxacin was superior to doxycycline. Doxycycline was also unable to control the levels of bacteria within tissues to the extent that doxycycline and finafloxacin used in combination or finafloxacin (as a sole therapy) could. In summary, finafloxacin is a promising therapy for use in the event of exposure to B. pseudomallei.

Histological sub-classification of cirrhosis using collagen proportionate area in patients with chronic hepatitis C.

Collagen proportionate area (CPA, %) is used to quantify liver fibrosis. Here, we assessed CPA performance to sub-classify cirrhosis. CPA was measured in explanted livers from consecutively transplanted patients for hepatitis C virus-related cirrhosis. Model for end-stage liver disease (MELD), Child-Pugh score and decompensating events (ascites, variceal bleeding, non-obstructive jaundice and encephalopathy) were recorded at the time of liver transplant. Of the 154 patients, 24%, 12%, 35%, 24% and 5% had zero, one, two, three and four previous decompensating events. Patients with decompensation had significantly higher CPA than those without (25.1 ± 8.4 vs 15.8 ± 5.5, P < .001). Decompensation was independently associated with CPA, bilirubin and albumin or with CPA and MELD score. CPA did not differ between patients with one, two, three or four decompensating events (22.2 ± 6.3 vs 26.6 ± 8.9 vs 24.5 ± 7.7 vs 24.4 ± 10.9, P = .242). Overall, CPA correlates with the clinical severity of cirrhosis until the advent of decompensation but not with subsequent decompensating events.

A Placebo-Controlled, Multicenter, Double-Blind, Phase 2 Randomized Trial of the Pan-Caspase Inhibitor Emricasan in Patients with Acutely Decompensated Cirrhosis.

BACKGROUND: Cirrhosis and acute-on-chronic liver failure (ACLF) are associated with systemic inflammation, and caspase-mediated hepatocyte cell death. Emricasan is a novel, pan-caspase inhibitor. Aims of this study were to assess the pharmacokinetics, pharmacodynamics, safety and clinical outcomes of emricasan in acute decompensation (AD) of cirrhosis. METHODS: This was a phase 2, multicentre, double-blind, randomized trial. The primary objective was to evaluate the pharmacokinetics, pharmacodynamics and safety of emricasan in patients with cirrhosis presenting with AD and organ failure. AD was defined as an acute decompensating event ≤6 weeks' duration. Patients were randomized proportionately to emricasan 5 mg bid, emricasan 25 mg bid, emricasan 50 mg bid or placebo. Treatment was continued to 28 days, or voluntary discontinuation. RESULTS: Twenty-three subjects were randomized, of whom 21 were dosed (placebo n = 4; 5 mg n = 5; 25 mg n = 7; 50 mg n = 5). Pharmacokinetic data showed 5 mg dose was associated with low plasma levels (<50 ng/ml), and 25 mg and 50 mg doses showed comparable pharmacokinetic profiles. Therefore, for analysis of secondary endpoints, placebo and 5 mg groups were merged into a 'placebo/low-dose' group, and 25 mg and 50 mg groups were merged into a 'high-dose' group. Five deaths occurred amongst the 21 patients, all due to progression of liver disease (2 in placebo/low-dose, 3 in high-dose). No statistically significant changes from baseline MELD score or CLIF-C ACLF score were noted between placebo/low-dose and high-dose groups at day 7 (MELD -1 vs -1, CLIF-C ACLF 0.7 vs 0.8). An initial reduction in cleaved keratin M30 fragment was noted between placebo/low-dose and high-dose groups (percent relative change: day 2: -11.6 vs -42.6, P = 0.017, day 4: -3.5 vs -38.9 P = 0.017) although this did not persist to day 7 (-3.1 vs -20.8, P = 0.342). CONCLUSION: This study demonstrates that emricasan is safe and well tolerated in advanced liver disease. However, this study fails to provide proof-of-concept support for caspase inhibition as a treatment strategy for ACLF. TRIAL REGISTRATION: EudraCT 2012-004245-33.

Randomized study of the safety and pharmacodynamics of inhaled interleukin-13 monoclonal antibody fragment VR942.

BACKGROUND: Interleukin-13 (IL-13) is a key mediator of T-helper-cell-type-2 (Th-2)-driven asthma, the inhibition of which may improve treatment outcomes. We examined the safety, pharmacokinetics, pharmacodynamics, and immunogenicity of VR942, a dry-powder formulation containing CDP7766, a high-affinity anti-human-IL-13 antigen-binding antibody fragment being developed for the treatment of asthma. METHODS: We conducted a phase 1, randomized, double-blind, placebo-controlled, ascending-dose study at Hammersmith Medicines Research, London, UK, which is now complete. Healthy adults aged 18-50 years (n = 40) were randomized 3:1 to a single inhaled dose of VR942 0.5, 1.0, 5.0, 10, or 20 mg, or placebo. Adults aged 18-50 years who were diagnosed with asthma for ≥6 months before screening, and had forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) values ≥70% of the predicted values at screening (n = 45), were randomized to once-daily inhaled VR942 0.5 or 10 mg, or placebo (2:2:1), or VR942 20 mg or placebo (3:2), for 10 days. All participants were randomized to receive VR942 or placebo based on a randomization list prepared by an independent HMR statistician using SAS® software (SAS Institute, Cary, NC). The primary outcome was safety and tolerability of VR942 (safety population, defined as all who received at least one dose of VR942 or placebo). This study is listed on ClinicalTrials.gov (NCT02473939). FINDINGS: In the VR942 and placebo groups, treatment-emergent adverse events (TEAEs) were reported in 10/30 (33%) and 0/10 (0%) healthy participants, and in 16/29 (55%) and 9/16 (56%) participants with asthma, respectively. Mild intermittent wheezing occurred in 7 participants (VR942 20 mg, n = 4; corresponding placebo, n = 3), resolving spontaneously within 1 h. All TEAEs were mild or moderate; there were no deaths, serious adverse events, or clinically significant changes in vital signs, electrocardiograms, or laboratory parameters. There was no clinically significant immunogenicity, with only one participant with asthma considered positive for treatment-related immunogenicity for CDP7766. INTERPRETATION: This study, considered to be the only example of a dry powder anti-IL-13 fragment antibody being administered via inhalation, demonstrated that single and repeat doses were well tolerated over a period of up to 10 days in duration. Rapid and durable inhibition of fractional exhaled nitric oxide (FeNO) (secondary outcome) provided evidence of pharmacological engagement with the IL-13 target in the airways of participants diagnosed with mild asthma. These data, together with the numerical improvements observed for predose FEV1, justify further clinical evaluation of VR942 in a broader population of patients with asthma, and continue to support the development of an inhaled anti-IL-13 antibody fragment as a potential future treatment that is alternative to monoclonal antibodies delivered via the parenteral route. FUNDING: Study funding and funding for the medical writing and editorial support for preparation of the manuscript were split equally between the two study co-funders (Vectura Ltd and UCB Pharma).

Migration of antioxidants from polylactic acid films, a parameter estimation approach: Part I - A model including convective mass transfer coefficient.

A two-step solution based on the boundary conditions of Crank's equations for mass transfer in a film was developed. Three driving factors, the diffusion (D), partition (Kp,f) and convective mass transfer coefficients (h), govern the sorption and/or desorption kinetics of migrants from polymer films. These three parameters were simultaneously estimated. They provide in-depth insight into the physics of a migration process. The first step was used to find the combination of D, Kp,f and h that minimized the sums of squared errors (SSE) between the predicted and actual results. In step 2, an ordinary least square (OLS) estimation was performed by using the proposed analytical solution containing D, Kp,f and h. Three selected migration studies of PLA/antioxidant-based films were used to demonstrate the use of this two-step solution. Additional parameter estimation approaches such as sequential and bootstrap were also performed to acquire a better knowledge about the kinetics of migration. The proposed model successfully provided the initial guesses for D, Kp,f and h. The h value was determined without performing a specific experiment for it. By determining h together with D, under or overestimation issues pertaining to a migration process can be avoided since these two parameters are correlated.

Migration of antioxidants from polylactic acid films: A parameter estimation approach and an overview of the current mass transfer models.

Migration studies of chemicals from contact materials have been widely conducted due to their importance in determining the safety and shelf life of a food product in their packages. The US Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA) require this safety assessment for food contact materials. So, migration experiments are theoretically designed and experimentally conducted to obtain data that can be used to assess the kinetics of chemical release. In this work, a parameter estimation approach was used to review and to determine the mass transfer partition and diffusion coefficients governing the migration process of eight antioxidants from poly(lactic acid), PLA, based films into water/ethanol solutions at temperatures between 20 and 50°C. Scaled sensitivity coefficients were calculated to assess simultaneously estimation of a number of mass transfer parameters. An optimal experimental design approach was performed to show the importance of properly designing a migration experiment. Additional parameters also provide better insights on migration of the antioxidants. For example, the partition coefficients could be better estimated using data from the early part of the experiment instead at the end. Experiments could be conducted for shorter periods of time saving time and resources. Diffusion coefficients of the eight antioxidants from PLA films were between 0.2 and 19×10-14m2/s at ~40°C. The use of parameter estimation approach provided additional and useful insights about the migration of antioxidants from PLA films.

Preliminary quantification of the permeability, solubility and diffusion coefficients of major aroma compounds present in herbs through various plastic packaging materials.

BACKGROUND: Aroma permeation through packaging material is an important factor when designing a package for food products. The masses of aroma compounds permeating through films over time were measured at 25 °C using a quasi-isostatic system. A model was proposed for estimating the permeability coefficients (P) of key aroma compounds present in fresh herbs (i.e. eucalyptol, estragole, linalool and citral) through major plastic films used by the food industry [i.e. low-density polyethylene (LDPE), polypropylene (PP), nylon (Nylon), polyethylene terephthalate (PET), metalised-polyethylene terephthalate (MPET) and poly(lactic acid) (PLA)]. Solubility coefficients (S) were estimated from the amount of aroma compound sorbed in the films. Diffusion coefficients (D) were estimated following from the relation P = D*S. RESULTS: P and D for all four aroma compounds were highest in LDPE, except for eucalyptol, which P was slightly higher in PLA. The solubility coefficients and contact angles were highest in PLA suggesting the highest affinity of PLA to these aroma compounds. The theoretical solubility parameters were correlated with the solubility coefficients for estragole and citral, but not for eucalyptol and linalool. CONCLUSION: The preliminary P, D and S of eucalyptol, estragole, linalool and citral through LDPE, PP, Nylon, PET, MPET and PLA can be useful in selecting the proper packaging material for preserving these specific aroma compounds in food products and can potentially be used for estimating the shelf life of food products based on aroma loss. © 2017 Society of Chemical Industry.

Digital image analysis of collagen assessment of progression of fibrosis in recurrent HCV after liver transplantation.

BACKGROUND & AIMS: Histological assessment of fibrosis progression is currently performed by staging systems which are not continuous quantitative measurements. We aimed at assessing a quantitative measurement of fibrosis collagen proportionate area (CPA), to evaluate fibrosis progression and compare it to Ishak stage progression. METHODS: We studied a consecutive cohort of 155 patients with recurrent HCV hepatitis after liver transplantation (LT), who had liver biopsies at one year and were subsequently evaluated for progression of fibrosis using CPA and Ishak staging, and correlated with clinical decompensation. The upper quartile of distribution of fibrosis rates (difference in CPA or Ishak stage between paired biopsies) defined fast fibrosers. RESULTS: Patients had 610 biopsies and a median follow-up of 116 (18-252) months. Decompensation occurred in 29 (18%) patients. Median Ishak stage progression rate was 0.42 units/year: (24 (15%) fast fibrosers). Median CPA fibrosis progression rate was 0.71%/year (36 (23%) fast fibrosers). Clinical decompensation was independently associated by Cox regression only with CPA (p=0.007), with AUROCs of 0.81 (95% CI 0.71-0.91) compared to 0.68 (95% CI 0.56-0.81) for Ishak stage. Fast fibrosis defined by CPA progression was independently associated with histological de novo hepatitis (OR: 3.77), older donor age (OR: 1.03) and non-use/discontinuation of azathioprine before 1 year post-LT (OR: 3.85), whereas when defined by Ishak progression, fast fibrosers was only associated with histological de novo hepatitis. CONCLUSIONS: CPA fibrosis progression rate is a better predictor of clinical outcome than progression by Ishak stage. Histological de novo hepatitis, older donor age and non-use/discontinuation of azathioprine are associated with rapid fibrosis progression in recurrent HCV chronic hepatitis after liver transplantation.

Ocular safety of sildenafil citrate when administered chronically for pulmonary arterial hypertension: results from phase III, randomised, double masked, placebo controlled trial and open label extension.

OBJECTIVE: To assess the ocular effects and safety profile of chronic sildenafil oral dosing in patients with pulmonary arterial hypertension. DESIGN: 12 week, double masked, randomised, placebo controlled, phase III trial with open label extension. SETTING: 53 institutions worldwide. PARTICIPANTS: 277 adults with idiopathic pulmonary arterial hypertension or pulmonary arterial hypertension associated with connective tissue disease or after congenital heart disease repair (mean pulmonary artery pressure ≥25 mm Hg; pulmonary capillary wedge pressure ≤15 mm Hg at rest). INTERVENTIONS: During the double masked study, oral sildenafil 20 mg, 40 mg, or 80 mg or placebo (1:1:1:1) three times daily for 12 weeks was added to baseline drug treatment. In the extension study, the placebo, 20 mg and 40 mg groups received 40 mg three times daily titrated to 80 mg three times daily at week 6. After unmasking, the dose was titrated according to clinical need. MAIN OUTCOME MEASURE: Ocular safety (ocular examinations, visual function tests, participants' reports of adverse events, and visual disturbance questionnaire completed by investigators) by treatment group at 12 weeks, 24 weeks, 18 months, and yearly. RESULTS: Findings of the objective assessments-that is, intraocular pressure and visual function tests (visual acuity, colour vision, and visual field)-were similar across groups (20 mg, n=69; 40 mg, n=67; 80 mg, n=71; placebo, n=70). No clinically significant changes occurred between baseline and 12 weeks, except for an efficacy signal in contrast sensitivity for the sildenafil 40 mg three times daily group. In right eyes, changes in intraocular pressure from baseline to week 12 ranged from a mean of -0.5 (95% confidence interval -1.3 to 0.2) mm Hg with placebo, -0.2 (-0.9 to 0.5) mm Hg with sildenafil 40 mg, and -0.1 (-0.7 to 0.5) mm Hg with 80 mg to 0.3 (-0.4 to 0.9) mm Hg with sildenafil 20 mg (the approved dose for pulmonary arterial hypertension). Mean changes from baseline to week 12 in contrast sensitivity in right eyes were -0.02 (SD 0.12) in the sildenafil 20 mg three times daily group compared with -0.05 (0.18) in the placebo group (P=0.044). Percentages of participants with deterioration in visual acuity (Snellen) from baseline to week 12 ranged from 10% (n=7) in the placebo group to 3% (n=2) in the sildenafil 20 mg three times daily group; the same percentages had visual field changes from normal to abnormal during the period in these two groups. The investigators did not deem any findings on colour vision assessment to be clinically significant. Findings of the objective assessments in the 40 mg and 80 mg three times daily sildenafil treatment groups and in left eyes were not substantially different, nor were any measures different throughout the open label extension compared with week 12. However, objective data were limited after month 18, as most participants had missing data or visual parameters were no longer collected by investigators. Incidence of ocular adverse events reported on the case report forms and assessed by the investigator was low with all doses, but a modest, dose related incidence of chromatopsia, cyanopsia, photophobia, and visual disturbance was reported with 80 mg three times daily consistent with the indicated dosing for erectile dysfunction. Retinal haemorrhages, captured on funduscopy, occurred in 2% (4/207) of sildenafil treated participants and none in the placebo group during the double masked study and in 4% (10/259) during the open label extension. CONCLUSIONS: Sildenafil dosing up to 80 mg three times daily is safe and well tolerated from an ocular perspective in patients with pulmonary arterial hypertension. Daily chronic dosing in this patient population was not associated with visual change and had no detrimental effect on best corrected visual acuity, contrast sensitivity, colour vision, or visual field, or on slit lamp examinations, funduscopy, or intraocular pressure during the duration of this study. TRIAL REGISTRATION: Clinical trials NCT00644605 and NCT00159887.

The mucosal addressin cell adhesion molecule antibody PF-00547,659 in ulcerative colitis: a randomised study.

BACKGROUND AND AIMS: Leucocyte migration to gut mucosa, mediated by integrin binding to mucosal addressin cell adhesion molecule (MAdCAM), is a promising target for therapeutic intervention in inflammatory bowel disease. This first-in-human study of a monoclonal antibody to MAdCAM, PF-00547,659, aimed to explore the safety and preliminary efficacy of this gut-specific mechanism in ulcerative colitis. METHODS: In this randomised, double-blind placebo-controlled study, 80 patients with active ulcerative colitis received single or multiple (three doses, 4-week intervals) doses of PF-00547,659 0.03-10 mg/kg IV/SC, or placebo. Safety was assessed by adverse events, laboratory tests, and immunogenicity. Exploratory efficacy analyses were based on Mayo score and endoscopic responder rates at weeks 4 and 12. Faecal calprotectin was quantified as a measure of disease activity, and the number of α4ß7⁺ lymphocytes was measured to demonstrate drug activity. RESULTS: No obvious drug-related side effects were observed in the PF-00547,659 group, while patient numbers, especially those fully exposed, were small. Overall responder/remission rates at 4 and 12 weeks were 52%/13% and 42%/22%, respectively with combined PF-00547,659 doses compared with 32%/11% and 21%/0%, respectively with placebo. Equivalent endoscopic responder rates were 50% and 42% versus 26% and 29%, respectively. Faecal calprotectin levels decreased to a greater extent with PF-00547,659 than placebo (week 4: 63% vs 18%). Despite variability, there was a trend for an increase in α4ß7⁺ lymphocytes in patients receiving PF-00547,659. CONCLUSIONS: The favourable short-term safety profile and preliminary efficacy findings for PF-00547,659 in this first-in-human study pave the way for further investigation in larger trials, to establish the role of PF-00547,659 in ulcerative colitis treatment. Trial Register No: NCT00928681.

Addition of sildenafil to long-term intravenous epoprostenol therapy in patients with pulmonary arterial hypertension: a randomized trial.

BACKGROUND: Oral sildenafil and intravenous epoprostenol have independently been shown to be effective in patients with pulmonary arterial hypertension. OBJECTIVE: To investigate the effect of adding oral sildenafil to long-term intravenous epoprostenol in patients with pulmonary arterial hypertension. DESIGN: A 16-week, double-blind, placebo-controlled, parallel-group study. SETTING: Multinational study at 41 centers in 11 countries from 3 July 2003 to 27 January 2006. PATIENTS: 267 patients with pulmonary arterial hypertension (idiopathic, associated anorexigen use or connective tissue disease, or corrected congenital heart disease) who were receiving long-term intravenous epoprostenol therapy. INTERVENTION: Patients were randomly assigned to receive placebo or sildenafil, 20 mg three times daily, titrated to 40 mg and 80 mg three times daily, as tolerated, at 4-week intervals. Of 265 patients who received treatment, 256 (97%) patients (123 in the placebo group and 133 in the sildenafil group) completed the study. MEASUREMENTS: Change from baseline in exercise capacity measured by 6-minute walk distance (primary end point) and hemodynamic measurements, time to clinical worsening, and Borg dyspnea score (secondary end points). RESULTS: A placebo-adjusted increase of 28.8 meters (95% CI, 13.9 to 43.8 meters) in the 6-minute walk distance occurred in patients in the sildenafil group; these improvements were most prominent among patients with baseline distances of 325 meters or more. Relative to epoprostenol monotherapy, addition of sildenafil resulted in a greater change in mean pulmonary arterial pressure by -3.8 mm Hg (CI, -5.6 to -2.1 mm Hg); cardiac output by 0.9 L/min (CI, 0.5 to 1.2 L/min); and longer time to clinical worsening, with a smaller proportion of patients experiencing a worsening event in the sildenafil group (0.062) than in the placebo group (0.195) by week 16 (P = 0.002). Health-related quality of life also improved in patients who received combined therapy compared with those who received epoprostenol monotherapy. There was no effect on the Borg dyspnea score. Of the side effects generally associated with sildenafil treatment, the most commonly reported in the placebo and sildenafil groups, respectively, were headache (34% and 57%; difference, 23 percentage points [CI, 12 to 35 percentage points]), dyspepsia (2% and 16%; difference, 13 percentage points [CI, 7 to 20 percentage points]), pain in extremity (18% and 25%; difference, 8 percentage points [CI, -2 to 18 percentage points]), and nausea (18% and 25%; difference, 8 percentage points [CI, -2 to 18 percentage points]). LIMITATIONS: The study excluded patients with pulmonary arterial hypertension associated with other causes. There was an imbalance in missing data between groups, with 8 placebo recipients having no postbaseline walk assessment compared with 1 sildenafil recipient. These patients were excluded from the analysis. CONCLUSION: In some patients with pulmonary arterial hypertension, the addition of sildenafil to long-term intravenous epoprostenol therapy improves exercise capacity, hemodynamic measurements, time to clinical worsening, and quality of life, but not Borg dyspnea score. Increased rates of headache and dyspepsia occurred with the addition of sildenafil.

Mutual pharmacokinetic interactions between steady-state bosentan and sildenafil.

OBJECTIVE: The aim of this study was to systematically investigate the mutual pharmacokinetic interactions in healthy volunteers between sildenafil, a phosphodiesterase-5 inhibitor, and bosentan, a dual endothelin receptor antagonist, both approved for treating pulmonary arterial hypertension (PAH). METHODS: A randomised, double-blind, placebo-controlled, parallel-group study with three treatment arms (sildenafil plus placebo, bosentan plus placebo and sildenafil plus bosentan) was conducted in 55 healthy male volunteers (51 completers). Study duration was 18 days per treatment group. Sildenafil was administered three times daily on Days 1-6 and 11-16 (20 mg initially, increased to 80 mg after 3 days), and bosentan (125 mg) was administered twice daily on Days 7-17. RESULTS: On Day 16, bosentan decreased the maximum plasma concentration of sildenafil (c)(max)) by 55.4% [90% confidence interval (CI) 40.3-66.6%] and the area under the plasma concentration versus time curve over a dosing interval (AUC(tau)) by 62.6% (90% CI 56.8-67.7%). Sildenafil increased bosentan C(max) by 42.0% (90% CI 15.4-74.8%) and (AUC(tau)) by 49.8% (90% CI 28.7-74.5%). Bosentan and sildenafil in combination were well tolerated, with no serious adverse events reported. All adverse events were of mild or moderate intensity. CONCLUSIONS: In healthy volunteers, there is a mutual pharmacokinetic interaction between bosentan and sildenafil that may influence the dosage of each drug in a combination treatment. The clinical implications of combination therapy with bosentan and sildenafil are as yet unknown, and further trials in patients with PAH are needed.

Sildenafil for pulmonary arterial hypertension associated with connective tissue disease.

OBJECTIVE: Pulmonary arterial hypertension associated with connective tissue disease (PAH-CTD) is difficult to manage, and has a poor prognosis. The phosphodiesterase-5 inhibitor sildenafil citrate enhances vasodilatation, has antiproliferative effects, and is effective in the treatment of PAH. We examined the efficacy and safety of oral sildenafil in patients with PAH-CTD. METHODS: In a 12-week, double-blind study (SUPER-1), 278 patients with PAH were randomized to oral placebo, sildenafil 20 mg, sildenafil 40 mg, or sildenafil 80 mg 3 times daily (tid). In a post-hoc subgroup analysis of 84 patients with PAH-CTD, exercise capacity, hemodynamic measures, World Health Organization functional class, and tolerability were assessed. RESULTS: Forty-five percent of the patients had scleroderma, 23% had systemic lupus erythematosus, and the rest (32%) were categorized as other. Patients were predominantly functional class II (38%) or III (61%) at baseline. Sildenafil-treated patients exhibited mean increases in 6-minute walk distance at Week 12 of 42 m (95% CI 20, 64) for 20 mg, 36 m (95% CI 14, 58) for 40 mg, and 15 m (95% CI -24, 54) for 80 mg, while placebo-treated patients exhibited a mean decrease of 13 m (95% CI -36, 10). Improvement of at least 1 functional class occurred in 29%-42% of sildenafil-treated patients, compared to 5% for placebo. Significant improvements in mean pulmonary arterial pressure and pulmonary vascular resistance were observed with sildenafil 20 mg, and sildenafil was generally well tolerated. CONCLUSION: In patients with PAH-CTD, sildenafil improves exercise capacity, hemodynamic measures (at the 20 mg dose), and functional class after 12 weeks of treatment.

Sildenafil citrate therapy for pulmonary arterial hypertension.

BACKGROUND: Sildenafil inhibits phosphodiesterase type 5, an enzyme that metabolizes cyclic guanosine monophosphate, thereby enhancing the cyclic guanosine monophosphate-mediated relaxation and growth inhibition of vascular smooth-muscle cells, including those in the lung. METHODS: In this double-blind, placebo-controlled study, we randomly assigned 278 patients with symptomatic pulmonary arterial hypertension (either idiopathic or associated with connective-tissue disease or with repaired congenital systemic-to-pulmonary shunts) to placebo or sildenafil (20, 40, or 80 mg) orally three times daily for 12 weeks. The primary end point was the change from baseline to week 12 in the distance walked in six minutes. The change in mean pulmonary-artery pressure and World Health Organization (WHO) functional class and the incidence of clinical worsening were also assessed, but the study was not powered to assess mortality. Patients completing the 12-week randomized study could enter a long-term extension study. RESULTS: The distance walked in six minutes increased from baseline in all sildenafil groups; the mean placebo-corrected treatment effects were 45 m (+13.0 percent), 46 m (+13.3 percent), and 50 m (+14.7 percent) for 20, 40, and 80 mg of sildenafil, respectively (P<0.001 for all comparisons). All sildenafil doses reduced the mean pulmonary-artery pressure (P=0.04, P=0.01, and P<0.001, respectively), improved the WHO functional class (P=0.003, P<0.001, and P<0.001, respectively), and were associated with side effects such as flushing, dyspepsia, and diarrhea. The incidence of clinical worsening did not differ significantly between the patients treated with sildenafil and those treated with placebo. Among the 222 patients completing one year of treatment with sildenafil monotherapy, the improvement from baseline at one year in the distance walked in six minutes was 51 m. CONCLUSIONS: Sildenafil improves exercise capacity, WHO functional class, and hemodynamics in patients with symptomatic pulmonary arterial hypertension.

Preference of distance learning methods among post-graduate occupational physicians and hygienists.

BACKGROUND: The Centre for Occupational and Environmental Health at the University of Manchester has successfully run distance-learning courses for a number of decades. These are based on hundreds of pages of (paper-based) written text, specially commissioned, packaged and distributed in eight binders. Converting printed text to an online format has the potential to improve learning through the benefits of information and communication technology as well as to save printing and distribution costs. AIM: To determine which distance learning method is preferred by postgraduate occupational health students: paper-based text, or online text with embedded interactive questions and separate practical exercises. METHODS: From approximately 50 paper-based textual course sub-units, one was converted to an online format, incorporating a variety of interactive text and supplemental practical exercises. Occupational medicine and hygiene students were provided with both the paper-based and online versions and asked, via anonymous postal questionnaire, a series of questions, including their preference for future course sub-units. RESULTS: Sixty-two replies were received from 91 registered students (68% response). Apart from one student who had never tried the internet, all others described themselves as 'frequent' or 'occasional' internet users, with 78% having access both at home and work. Opinion was overwhelmingly positive with regard to ease of navigation, quality of the interactive exercises and online photo quality. Students tended to prefer multiple-choice questions and photo exercises and disliked interactive functions asking for words to complete paragraphs. Regarding preference for future teaching sub-units, the majority of students answering this question (67%) expressed a desire for mostly paper-based text supplemented with interactive online exercises. CONCLUSION: Currently enrolled students prefer core teaching materials to remain in the printed medium, with the addition of online practical exercises to supplement learning.

Retrospective noise estimates for British nuclear workers using an alternative approach.

Exposure estimates were required to support an epidemiological study of occupational noise and cardiovascular disease. The study cohort consisted of male industrial workers employed at two nuclear facilities in England between 1945 and 1999 (n=2412). Historical noise exposure data were available from 6850 sound pressure measurements collected since 1965. Additional information was obtained from interviews with retired and long-term company personnel. Partly due to the lack of information provided by job title, coupled with the fact that noise behaves differently compared with chemical agents, an unusual approach was used to estimate noise exposure. Rather than grouping homogeneous exposure groups by job title or task, the assessors first used historical sampling data to estimate average area noise levels in each workplace where a survey had been performed. Noise contours were then estimated in the work area and, finally, individual estimates of exposure were further refined based on job title. Estimates were extrapolated to areas where noise surveys were not performed and adjustments were made for potential bias. Overall, noise exposure estimates ranged from 60 to 97 dBA, with a median of 86 dBA. For use in subsequent exposure-response analysis, cohort work histories were used to calculate exposure indices of cumulative, average intensity and exposure duration above 85 dBA. Validation exercises are discussed.

Compliance with the manual handling regulations amongst a random selection of small businesses in England.

Manual handling activities have long been recognized as major contributors to occupational injury and ill health. Following a series of consultative documents, the Manual Handling Operations Regulations (MHORs) and their associated Guidance came into force in the UK in January 1993. More than 5 yr on, an investigation was performed to evaluate response to this legislation amongst a random selection of small businesses within a business district of Shropshire, England. A postal questionnaire was sent to 100 companies employing 5-50 workers. Responses were obtained from 80 companies, ranging from retailing to metals/engineering. Although all of the companies are likely to perform activities requiring manual handling assessments under the MHORs, many claimed never to have heard of the legislation (38%) and almost half (46%) had not performed an assessment. Compliance varied significantly by business type, with the nine companies engaged in metals/engineering reporting significantly better compliance (P < 0.05). Of the 43 companies who claimed to have undertaken assessments, 73% (32 companies) indicated that manual handling activities had been changed, with all claiming to have reduced lifting activities, a significant proportion (75%) making improvements to the working environment and over half (59%) reducing the weight of loads. Many of the companies who indicated full compliance with the legislation (21 companies) stated that the benefits to their businesses outweighed the cost of compliance. Additional factors analysed by the study include source of legislative awareness, personnel performing assessments, employee training and method used, and reasons for non-compliance with the MHORs.

Observations of ethical misconduct among industrial hygienists in England.

Industrial hygienists are uniquely situated to help solve problems in the working environment, and failure to behave ethically might have serious and possibly fatal consequences. A survey was conducted to estimate the prevalence and nature of ethical misconduct within the UK occupational hygiene profession during the past 5 years. A postal questionnaire was sent to 50 professional industrial/occupational hygienists. Of the 43 respondents, 33 (77%) had witnessed activities of potential ethical misconduct in at least one of nine questionnaire categories. Additionally, greater than 20% of the hygienists had witnessed at least one incident of data fabrication, failure to share credit on work, failure to protect confidentiality, criticizing the integrity of another hygienist for one's own gain, and plagiarism. The investigation also asked hygienists for their opinions on the reasons for breaches as well as potential methods of improvement.