Effect of Selenium Nanoparticle Size on IL-6 Detection Sensitivity in a Lateral Flow Device.

Sepsis is the body's response to an infection. Existing diagnostic testing equipment is not available in primary care settings and requires long waiting times. Lateral flow devices (LFDs) could be employed in point-of-care (POC) settings for sepsis detection; however, they currently lack the required sensitivity. Herein, LFDs are constructed using 150-310 nm sized selenium nanoparticles (SeNPs) and are compared to commercial 40 nm gold nanoparticles (AuNPs) for the detection of the sepsis biomarker interleukin-6 (IL-6). Both 310 and 150 nm SeNPs reported a lower limit of detection (LOD) than 40 nm AuNPs (0.1 ng/mL compared to 1 ng/mL), although at the cost of test line visual intensity. This is to our knowledge the first use of larger SeNPs (>100 nm) in LFDs and the first comparison of the effect of the size of SeNPs on assay sensitivity in this context. The results herein demonstrate that large SeNPs are viable alternatives to existing commercial labels, with the potential for higher sensitivity than standard 40 nm AuNPs.

The Anti-Obesity Effect of Porous Silica Is Dependent on Pore Nanostructure, Particle Size, and Surface Chemistry in an In Vitro Digestion Model.

The potential for porous silica to serve as an effective anti-obesity agent has received growing attention in recent years. However, neither the exact pharmacological mechanism nor the fundamental physicochemical properties of porous silica that drive its weight-lowering effect are well understood. Subsequently, in this study, an advanced in vitro digestion model capable of monitoring lipid and carbohydrate digestion was employed to elucidate the effect of porous silica supplementation on digestive enzyme activities. A suite of porous silica samples with contrasting physicochemical properties was investigated, where it was established that the inhibitory action of porous silica on digestive enzyme functionality was strongly dependent on porous nanostructure, particle size and morphology, and surface chemistry. Insights derived from this study validate the capacity of porous silica to impede the digestive processes mediated by pancreatic lipase and α-amylase within the gastrointestinal tract, while the subtle interplay between porous nanostructure and enzyme inhibition indicates that the anti-obesity effect can be optimized through strategic particle design.

Analytical method validation for assay determination of cannabidiol and tetrahydrocannabinol in hemp oil infused products by RP-HPLC.

A simple quantitative reverse phase high performance liquid chromatographic (RP-HPLC) method has been developed and validated for assay determination of cannabidiol and tetrahydrocannabinol in hemp oil infused products. The RP-HPLC method was developed and optimized for the mobile phase composition, flow rate, column selection and detector wavelength. An isocratic elution of samples were performed on SOLAS 100 Å C18 150 mm × 4.6 mm, 5 µm column with a mobile phase containing 75/25 acetonitrile/water v/v, with a flow rate of 1.5 mL/min by using an ultraviolet-visible (UV/Vis) detector operating at 214 nm. The RP-HPLC method was validated to meet regulatory requirements which covers specificity, accuracy, range, linearity, precision, system suitability and robustness. The validated assay test method was applied successfully to quantify cannabidiol and tetrahydrocannabinol in commercial hemp oil infused products such as tablets, soft gel capsules, plant extract oils, oral drops, tincture, and beverage enhancers. All the test results were found acceptable as per ICH guidelines, and this confirmed the feasibility of this method for its intended use in regular quality control and assay of cannabidiol and tetrahydrocannabinol in hemp oil infused products.

Effects of the Soluble Guanylate Cyclase Stimulator Praliciguat in Diabetic Kidney Disease: A Randomized Placebo-Controlled Clinical Trial.

BACKGROUND AND OBJECTIVES: Impaired nitric oxide signaling through soluble guanylate cyclase has been implicated in the pathophysiology of diabetic kidney disease. Praliciguat, a soluble guanylate cyclase stimulator that amplifies nitric oxide signaling, inhibited kidney inflammation and fibrosis in animal models. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In a phase 2 trial, 156 adults with type 2 diabetes, eGFR 30-75 ml/min per 1.73 m2, and urine albumin-creatinine ratio 200-5000 mg/g treated with renin-angiotensin system inhibitors were randomly allocated 1:1:1 to placebo, 20 mg praliciguat, or 40 mg praliciguat daily for 12 weeks. The primary efficacy and safety outcomes were change from baseline to weeks 8 and 12 in urine albumin-creatinine ratio and treatment-emergent adverse events, respectively. Other outcomes assessed were 24-hour ambulatory BP and metabolic parameters. RESULTS: Of 156 participants randomized, 140 (90%) completed the study. The primary efficacy analysis demonstrated a mean change from baseline in urine albumin-creatinine ratio of -28% (90% confidence interval, -36 to -18) in the pooled praliciguat group and -15% (-28 to 0.4) in the placebo group (difference -15%; -31 to 4; P=0.17). Between-group decreases from baseline to week 12 for praliciguat versus placebo were seen in mean 24-hour systolic BP (-4 mm Hg; -8 to -1), hemoglobin A1c (-0.3%; -0.5 to -0.03), and serum cholesterol (-10 mg/dl; -19 to -1). The incidence of treatment-emergent adverse events was similar in the pooled praliciguat and placebo groups (42% and 44%, respectively). Serious adverse events, events leading to study drug discontinuation, and events potentially related to BP lowering were reported at higher frequency in the 40-mg group but were similar in 20-mg and placebo groups. CONCLUSIONS: Praliciguat treatment for 12 weeks did not significantly reduce albuminuria compared with placebo in the primary efficacy analysis. Nonetheless, the observed changes in urine albumin-creatinine ratio, BP, and metabolic variables may support further investigation of praliciguat in diabetic kidney disease. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: A Study to Evaluate the Soluble Guanylate Cyclase (sGC) Stimulator IW-1973 in Diabetic Nephropathy/Diabetic Kidney Disease as Measured by Albuminuria, NCT03217591.

An exploratory, randomised, placebo-controlled, 14 day trial of the soluble guanylate cyclase stimulator praliciguat in participants with type 2 diabetes and hypertension.

AIMS/HYPOTHESIS: Praliciguat (IW-1973), a soluble guanylate cyclase stimulator, amplifies nitric oxide signalling. This exploratory trial investigated the safety, tolerability, pharmacokinetic profile and pharmacodynamic effects of praliciguat in individuals with type 2 diabetes and hypertension. METHODS: This Phase IIA, double-blind, placebo-controlled trial investigated praliciguat in 26 participants with type 2 diabetes and hypertension on stable glucose- and BP-lowering therapies. Participants were randomly allocated in a 3:5:5 ratio to three groups: placebo (n = 6), praliciguat 40 mg once daily for days 1-14 (n = 10), or praliciguat 20 mg twice daily for days 1-7 then 40 mg once daily for days 8-14 (n = 10). Assessments were made in clinic and included treatment-emergent adverse events, pharmacokinetics, metabolic variables, 24 h BP and heart rate, platelet function, reactive hyperaemia index (RHI) and plasma biomarkers. Participants, the sponsor, the investigator and clinic study staff (except designated pharmacy personnel) were blinded to group assignment. RESULTS: Participants treated for 14 days with praliciguat had least-square mean change-from-baseline differences vs placebo (95% CI) of -0.7 (-1.8, 0.4) mmol/l for fasting plasma glucose, -0.7 (-1.1, -0.2) mmol/l for total cholesterol, -0.5 (-1.0, -0.1) mmol/l for LDL-cholesterol, -23 (-56, 9) for HOMA-IR in those not being treated with insulin, and -5 (-10, 1) mmHg and 3 (-1, 6) beats/min for average 24 h mean arterial pressure and heart rate, respectively. Apart from one serious adverse event (SAE; upper gastrointestinal haemorrhage), praliciguat was well tolerated. Praliciguat did not affect platelet function or RHI. Among exploratory biomarkers, plasma levels of asymmetric dimethylarginine decreased in praliciguat vs placebo recipients. CONCLUSIONS/INTERPRETATION: In participants with type 2 diabetes and hypertension on standard therapies, over 14 days praliciguat was well tolerated, except for a single SAE, and showed positive trends in metabolic and BP variables. These results support further clinical investigation of praliciguat. TRIAL REGISTRATION: ClinicalTrials.gov NCT03091920. FUNDING: This trial was funded by Cyclerion Therapeutics.

A Randomized, Placebo-Controlled, Multiple-Ascending-Dose Study to Assess the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of the Soluble Guanylate Cyclase Stimulator Praliciguat in Healthy Subjects.

Nitric oxide (NO)-soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) signaling is central to the regulation of several physiological processes, including blood flow and inflammation. Deficient NO signaling is implicated in multiple diseases. sGC stimulators are small molecules that enhance sGC activity, particularly in combination with NO. In a randomized, placebo-controlled phase 1 study, the safety, tolerability, pharmacokinetics, and pharmacodynamics of multiple ascending doses of the sGC stimulator praliciguat were assessed in 44 healthy adults. Four cohorts of 11 subjects (8 praliciguat, 3 placebo) received once-daily praliciguat for 14 days before up-titrating for 7 days (treatment sequences: 15/30 mg, 20/40 mg, 30/40 mg, and weight-based). All doses were tolerated. No serious or severe adverse events (AEs) were reported. The most common AEs in praliciguat recipients were headache and symptoms consistent with blood pressure (BP) lowering/vasodilation. There were no laboratory, vital sign, electrocardiographic, or platelet function findings indicative of a safety concern. Pharmacokinetics were dose proportional, with an effective half-life of 24-37 hours, supporting once-daily dosing. Praliciguat produced dose-related increases in plasma cGMP consistent with stimulation of sGC. Repeated once-daily dosing showed sustained decreases in BP. Results support evaluation of praliciguat for the treatment of conditions associated with deficient NO signaling.

Enhancing the dissolution of phenylbutazone using Syloid® based mesoporous silicas for oral equine applications.

Three mesoporous silica excipients (Syloid® silicas AL-1 FP, XDP 3050 and XDP 3150) were formulated with a model drug known for its poor aqueous solubility, namely phenylbutazone, in an attempt to enhance the extent and rate of drug dissolution. Although other forms of mesoporous silica have been investigated in previous studies, the effect of inclusion with these specific Syloid® silica based excipients and more interestingly, with phenylbutazone, is unknown. This work reports a significant enhancement for both the extent and rate of drug release for all three forms of Syloid® silica at a 1:1 drug:silica ratio over a period of 30 min. An explanation for this increase was determined to be conversion to the amorphous form and an enhanced drug loading ability within the pores. Differences between the release profiles of the three silicas were concluded to be a consequence of the physicochemical differences between the three forms. Overall, this study confirms that Syloid® silica based excipients can be used to enhance dissolution, and potentially therefore bioavailability, for compounds with poor aqueous solubility such as phenylbutazone. In addition, it has been confirmed that drug release can be carefully tailored based on the choice of Syloid® silica and desired release profile.

Comparison of fenofibrate-mesoporous silica drug-loading processes for enhanced drug delivery.

Loading a poorly water-soluble drug onto a high surface area carrier such as mesoporous silica (SBA-15) can increase the drug's dissolution rate and oral bioavailability. The loading method can influence subsequent drug properties including solid state structure and release rate. The objective of this research was to compare several loading processes in terms of drug distribution throughout the mesoporous silica matrix, drug solid state form and drug release properties. A model poorly water-soluble drug fenofibrate was loaded onto SBA-15 using; (i) physical mixing, (ii) melt, (iii) solvent impregnation, (iv) liquid CO2 and (v) supercritical CO2 methods. Physical mixing resulted in heterogeneous drug-loading, with no evidence of drug in the mesopores and the retention of the drug in its crystalline state. The other loading processes yielded more homogeneous drug-loading; the drug was deposited into the mesopores of the SBA-15 and was non-crystalline. All the processing methods resulted in enhanced drug release compared to the unprocessed drug with the impregnation, liquid and SC-CO2 producing the greatest increase at t=30 min.

Inclusion of fenofibrate in a series of mesoporous silicas using microwave irradiation.

A selection of porous silicas were combined with a model drug using a recently developed, controlled microwave heating process to determine if the application of microwave irradiation could enhance subsequent drug release. Five mesoporous silica types were investigated (core shell, core shell rehydrox, SBA-15, silica gel, SYLOID®) and, for comparison, one non-porous silica (stober). These were formulated using a tailored microwave heating method at drug/excipient ratios of 1:1, 1:3 and 1:5. In addition, all experiments were performed both in the presence and absence of water, used as a fluidising media to aid interaction between drug and support, and compared with results obtained using more traditional heating methods. All formulations were then characterised using differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transformation infrared spectroscopy (FT-IR). Pharmaceutical performance was investigated using in vitro drug release studies. A significant enhancement in the release profile of fenofibrate was observed for formulations prepared using microwave heating in the absence of water for five of the six silica based formulations. Of all the formulations analysed, the greatest extent of drug release within the experimental 30 min was the 1:5 core shell rehydrox achieving a total of 86.6 ± 2.8%. The non-porous (stober) particles did not exhibit an increased release of the drug under any experimental conditions studied. This anomaly is thought to be a result of the comparatively small surface area of the silica particles, thus preventing the adsorption of drug molecules.

Genome-wide association analysis in asthma subjects identifies SPATS2L as a novel bronchodilator response gene.

Bronchodilator response (BDR) is an important asthma phenotype that measures reversibility of airway obstruction by comparing lung function (i.e. FEV(1)) before and after the administration of a short-acting ß(2)-agonist, the most common rescue medications used for the treatment of asthma. BDR also serves as a test of ß(2)-agonist efficacy. BDR is a complex trait that is partly under genetic control. A genome-wide association study (GWAS) of BDR, quantified as percent change in baseline FEV(1) after administration of a ß(2)-agonist, was performed with 1,644 non-Hispanic white asthmatic subjects from six drug clinical trials: CAMP, LOCCS, LODO, a medication trial conducted by Sepracor, CARE, and ACRN. Data for 469,884 single-nucleotide polymorphisms (SNPs) were used to measure the association of SNPs with BDR using a linear regression model, while adjusting for age, sex, and height. Replication of primary P-values was attempted in 501 white subjects from SARP and 550 white subjects from DAG. Experimental evidence supporting the top gene was obtained via siRNA knockdown and Western blotting analyses. The lowest overall combined P-value was 9.7E-07 for SNP rs295137, near the SPATS2L gene. Among subjects in the primary analysis, those with rs295137 TT genotype had a median BDR of 16.0 (IQR = [6.2, 32.4]), while those with CC or TC genotypes had a median BDR of 10.9 (IQR = [5.0, 22.2]). SPATS2L mRNA knockdown resulted in increased ß(2)-adrenergic receptor levels. Our results suggest that SPATS2L may be an important regulator of ß(2)-adrenergic receptor down-regulation and that there is promise in gaining a better understanding of the biological mechanisms of differential response to ß(2)-agonists through GWAS.

Structural variation of solid core and thickness of porous shell of 1.7 µm core-shell silica particles on chromatographic performance: narrow bore columns.

Chromatographic and mass transfer kinetic properties of three narrow bore columns (2.1×50 mm) packed with new core-shell 1.7 µm EIROSHELL™-C(18) (EiS-C(18)) particles have been studied. The particles in each column varied in the solid-core to shell particle size ratio (ρ), of 0.59, 0.71 and 0.82, with a porous silica shell thickness of 350, 250 and 150 nm respectively. Scanning and transmission electron microscopy (SEM and TEM), Coulter counter analysis, gas pycnometry, nitrogen sorption analysis and inverse size exclusion chromatography (ISEC) elucidated the physical properties of these materials. The porosity measurement of the packed HILIC and C(18) modified phases provided the means to estimate the phase ratios of the three different shell columns (EiS-150-C(18), EiS-250-C(18) and EiS-350-C(18)). The dependence of the chromatographic performance to the volume fraction of the porous shell was observed for all three columns. The naphtho[2,3-a]pyrene retention factor of k'∼10 on the three EiS-C(18s) employed to obtain the height equivalents to theoretical plates (HETPs) data were achieved by varying the mobile phase compositions and applying the Wilke and Chang relationship to obtain a parallel reduced linear velocity. The Knox fit model gave the coefficient of the reduce HETPs for the three EiS-C(18s). The reduced plate height minimum h(min)=1.9 was achieved for the EiS-150-C(18) column, and generated an efficiency of over 350,000 N/m and h(min)=2.5 equivalent to an efficiency of 200,000 N/m for the EiS-350-C(18) column. The efficiency loss of the EiS-C18 column emanating from the system extra-column volume was discussed with respect to the porous shell thickness.

Regulatory haplotypes in ARG1 are associated with altered bronchodilator response.

RATIONALE: ß2-agonists, the most common treatment for asthma, have a wide interindividual variability in response, which is partially attributed to genetic factors. We previously identified single nucleotide polymorphisms in the arginase 1 (ARG1) gene, which are associated with ß2-agonist bronchodilator response (BDR). OBJECTIVES: To identify cis-acting haplotypes in the ARG1 locus that are associated with BDR in patients with asthma and regulate gene expression in vitro. METHODS: We resequenced ARG1 in 96 individuals and identified three common, 5' haplotypes (denoted 1, 2, and 3). A haplotype-based association analysis of BDR was performed in three independent, adult asthma drug trial populations. Next, each haplotype was cloned into vectors containing a luciferase reporter gene and transfected into human airway epithelial cells (BEAS-2B) to ascertain its effect on gene expression. MEASUREMENTS AND MAIN RESULTS: BDR varied by haplotype in each of the three populations with asthma. Individuals with haplotype 1 were more likely to have higher BDR, compared to those with haplotypes 2 and 3, which is supported by odds ratios of 1.25 (95% confidence interval, 1.03-1.71) and 2.18 (95% confidence interval, 1.34-2.52), respectively. Luciferase expression was 50% greater in cells transfected with haplotype 1 compared to haplotypes 2 and 3. CONCLUSIONS: The identified ARG1 haplotypes seem to alter BDR and differentially regulate gene expression with a concordance of decreased BDR and reporter activity from haplotypes 2 and 3. These findings may facilitate pharmacogenetic tests to predict individuals who may benefit from other therapeutic agents in addition to ß(2)-agonists for optimal asthma management. Clinical trial registered with www.clinicaltrials.gov (NCT00156819, NCT00046644, and NCT00073840).

Development of chemically engineered porous metal oxides for phosphate removal.

In this study, the application of ordered mesoporous silica (OMS) doped with various metal oxides (Zr, Ti, Fe and Al) were studied for the removal of (ortho) phosphate ions from water by adsorption. The materials were characterized by means of N(2) physisorption (BET), powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM). The doped materials had surface areas between 600 and 700 m(2)g(-1) and exhibited pore sizes of 44-64 Å. Phosphate adsorption was determined by measurement of the aqueous concentration of orthophosphate using ultraviolet-visible (UV-vis) spectroscopy before and after extraction. The effects of different metal oxide loading ratios, initial concentration of phosphate solution, temperature and pH effects on the efficiency of phosphate removal were investigated. The doped mesoporous materials were effective adsorbents of orthophosphate and up to 100% removal was observed under appropriate conditions. 'Back extracting' the phosphate from the doped silica (following water treatment) was also investigated and shown to have little adverse effect on the adsorbent.

Porous silica spheres as indoor air pollutant scavengers.

Porous silica spheres were investigated for their effectiveness in removing typical indoor air pollutants, such as aromatic and carbonyl-containing volatile organic compounds (VOCs), and compared to the commercially available polymer styrene-divinylbenzene (XAD-4). The silica spheres and the XAD-4 resin were coated on denuder sampling devices and their adsorption efficiencies for VOCs evaluated using an indoor air simulation chamber. Real indoor sampling was also undertaken to evaluate the affinity of the silica adsorbents for a variety of indoor VOCs. The silica sphere adsorbents were found to have a high affinity for polar carbonyls and found to be more efficient than the XAD-4 resin at adsorbing carbonyls in an indoor environment.

Preparation, characterisation and modification of carbon-based monolithic rods for chromatographic applications.

A range of porous carbon-based monolithic (PCM) rods with flow-through pore sizes of 1, 2, 5 and 10 mum, were produced using a silica particle template method. The rods were characterised using SEM and energy-dispersive X-ray spectroscopy, BET surface area and porous structure analysis, dilatometry and thermal gravimetry. SEM evaluation of the carbon monolithic structures revealed an interconnected rigid bimodal porous structure and energy-dispersive X-ray spectroscopy analysis verified the quantitative removal of the embedded silica beads. The specific surface areas of the 1, 2, 5 and 10 mum rods were 178, 154, 84 and 125 m(2)/g after pyrolysis and silica removal, respectively. Shrinkage of the monolithic rods during pyrolysis is proportional to the particle size of the silica used and ranged from 9 to 12%. Mercury porosimetry showed a narrow distribution of pore sizes, with an average of approximately 700 nm for the 1 mum carbon monolith. The suitability of bare and surface oxidised PCM rods for the use as a stationary phase for reversed and normal phase LC was explored. The additional modification of PCM rods with gold micro-particles followed by 6-mercaptohexanoic acid was performed and ion-exchange properties were evaluated.

Swelling of ionic and nonionic surfactant micelles by high pressure gases.

The influence of different solvent environments on the size, shape, and characteristics of surfactant micelles of Pluronic F127 and CTAB was investigated by small-angle neutron scattering (SANS). SANS experiments were undertaken on dilute micellar surfactant solutions of F127 and CTAB that between them were exposed to liquid and supercritical carbon dioxide, liquid propane, ethane, and heptane under various pressures and temperatures. Swelling of the surfactant micelles could be directly related to the solubility of the solvents within the micelles, especially within their cores. Carbon dioxide produced the largest swelling of the Pluronic F127 micelles, compared to propane and ethane, which mirrors the solubility of the gases in the PPO core of the micelles. Conversely, the extent of swelling of the cores of CTAB micelles was greater with propane compared to carbon dioxide, which again relates to the solubility of the solvents in the alkane core of the CTAB micelles.

Output and aerosol properties of 5 nebulizer/compressor systems with arformoterol inhalation solution.

BACKGROUND: Arformoterol, the (R,R) isomer of formoterol, is approved as an inhalation solution for the treatment of bronchoconstriction in patients with chronic obstructive pulmonary disease. Multiple nebulizer systems are commercially available. Different nebulizers can differ significantly in drug output, which may impact drug delivery and clinical efficacy. This study compared the aerosol properties of arformoterol delivered via 5 commonly used nebulizer systems for the home-care market. METHODS: The delivered dose of arformoterol inhalation solution (15 microg/2 mL) was collected in a glass Dreschel-type apparatus. The delivered amount in fine-droplet fraction was assessed with an Andersen cascade impactor, and droplet size (average median diameter and average percent<5 microm) was evaluated via laser diffraction. Compressor flow rate measurements were taken after 1 min and 6 min by placing the flow meter in line with each system. RESULTS: The Pari LC Plus, Updraft II Opti-Neb, and NebuTech systems delivered similar amounts of the 15-microg nominal dose (from 23% to 25%). The Pari LC Star and Sidestream systems delivered slightly higher doses (31% and 35%, respectively). The nebulizer/compressor systems differed somewhat with respect to droplet size. The NebuTech delivered the lowest fine-droplet fraction (61%) via Andersen cascade impactor, and the smallest percent of droplets<5 microm (40%) via laser diffraction. The Pari LC Star and Sidestream delivered the highest fine-droplet fraction (100% and 93%, respectively), and the greatest percent of droplets<5 microm (84% and 88%). The fine-droplet fractions for the Updraft II Opti-Neb and Pari LC Plus were 93% and 89%, respectively, and the percent of droplets<5 microm was about 67%. Compressor flow rates ranged from 3.2 L/min (Pari LC Plus) to 5.4 L/min (NebuTech). CONCLUSIONS: The results of this study demonstrate that the choice of nebulizer/compressor system can influence the aerosol properties of arformoterol inhalation solution and should be considered when prescribing nebulized medications.

The influence of breathing pattern during nebulization on the delivery of arformoterol using a breath simulator.

BACKGROUND: Patients with obstructive airway conditions, including chronic obstructive pulmonary disease (COPD), use nebulizers for drug delivery. Tidal breathing patterns employed by patients during nebulized drug delivery may vary. It is unclear whether different breathing patterns affect the emitted quantity of nebulized drug. This in vitro study evaluated whether different tidal breathing patterns that encompass a range that could be observed in COPD patients influence the emitted amount of nebulized arformoterol. METHODS: Breath-simulation experiments used a Pari LC Plus nebulizer in combination with the Duraneb 3000 portable aerosol system. Four breathing patterns that could represent a range of tidal volumes and inspiratory and expiratory times observed in patients with COPD were studied. The amount of arformoterol on the inspiratory and expiratory filters, and the residual amount in the nebulizer bowl were determined via high-pressure liquid chromatography. Results are expressed as a percent of the nominal dose (15 microg in 2 mL). RESULTS: The total amount of arformoterol on the inspiratory filter increased with a longer inspiratory phase of tidal breathing (ranging from 8.0% to 13.1%), while the expiratory filter dose remained similar (7.9% to 8.7%). The total emitted dose (expiratory and inspiratory amounts combined) for all patterns was 16.0% to 21.1% of the nominal dose. Retained arformoterol amount (not emitted) ranged from 55.9% to 62.3% of the nominal dose. CONCLUSIONS: These breath-simulation experiments suggest that only about 20% of the nominal 15-microg arformoterol dose was emitted from the nebulizer apparatus with each of the 4 tidal breathing patterns studied, and that a longer inspiratory phase was associated with greater inhaled dose.

Large pore bi-functionalised mesoporous silica for metal ion pollution treatment.

Here we demonstrate aminopropyl and mercatopropyl functionalised and bi-functionalised large pore mesoporous silica spheres to extract various metal ions from aqueous solutions towards providing active sorbents for mitigation of metal ion pollution. Elemental analysis (EA) and FTIR techniques were used to quantify the attachment of the aminopropyl and mercatopropyl functional groups to the mesoporous silica pore wall. Functionalisation was achieved by post-synthesis reflux procedures. For all functionalised silicas the functionalisation refluxing does not alter particle morphology/agglomeration of the particles. It was found that sorptive capacities of the mesoporous silica towards the functional groups were unaffected by co-functionalisation. Powder X-ray diffraction (PXRD) and nitrogen adsorption techniques were used to establish the pore diameters, packing of the pores and specific surface areas of the modified mesoporous silica spheres. Atomic absorption (AA) spectroscopy and inductively coupled plasma-atomic emission spectrometry (ICP-AES) techniques were used to measure the extraction efficiencies of each metal ion species from solution at varying pHs. Maximum sorptive capacities (as metal ions) were determined to be 384micromolg(-1) for Cr, 340micromol g(-1) for Ni, 358micromol g(-1) for Fe, 364micromol g(-1) for Mn and 188micromol g(-1) for Pd.

Arrhythmias in patients with chronic obstructive pulmonary disease (COPD): occurrence frequency and the effect of treatment with the inhaled long-acting beta2-agonists arformoterol and salmeterol.

Beta-adrenergic stimulation may increase heart rate and the potential for cardiac arrhythmias. The effect of inhaled long-acting beta2-agonists (LABAs) on these outcomes was evaluated in patients with chronic obstructive pulmonary disease (COPD) in 2 double-blind randomized clinical trials. The pretreatment arrhythmia occurrence frequency in these patients was also described. In this analysis, 24-hour Holter monitoring data were pooled from 2 identically designed Phase III trials. Patients were randomized to LABA treatment or placebo for 12 weeks: a) nebulized arformoterol 15 microg BID, b) 25 microg BID, or c) 50 microg QD; d) salmeterol metered dose inhaler 42 microg BID; or e) placebo. The 24-hour Holter monitoring was performed pretreatment and at Weeks 0 (first day of dosing), 6, and 12. We assessed the proportion of patients with each of 4 arrhythmias: atrial tachycardia, atrial fibrillation/flutter, and "nonsustained"; (4-10 beats) and "sustained"; (>10 beats) ventricular tachycardia. There were 5226 Holter recordings in 1429 treated patients. At baseline, there was a low frequency of occurrence of atrial fibrillation/flutter (0.1%), nonsustained ventricular tachycardia (3.1%), and >10 beat ventricular tachycardia (0.3%). Atrial tachycardia occurred frequently (41.8%). The proportion of patients with treatment-emergent atrial tachycardia ranged from 27% to 32% and was non-significantly higher, by approximately 2%-5% (p = 0.70), in the LABA groups compared with the placebo group. The rates of the other more serious arrhythmias did not increase with LABA treatment and were similar to placebo. All treatment groups (LABA and placebo) had consistent small decreases from baseline in mean 24-hour and maximum hourly heart rate. In conclusion, in this large cohort of COPD patients with no or stable cardiac comorbidities, a high proportion ( approximately 40%) of patients were observed to have atrial tachycardia before treatment, which increased by 2%-5% with LABA treatment. More serious arrhythmias were infrequent and did not increase with inhaled LABA therapy. LABA administration did not increase mean heart rate.