Measurement of exhaled hydrocarbons

Oxidative stress is implicated in the pathogenesis and progression of asthma (1,2), chronic obstructive respiratory disease (COPD) (3), and cystic fibrosis (4). Reactive oxygen species (ROS) are unstable compounds with unpaired electrons, capable of initiating oxidation. Several of the inflammatory cells which participate in the inflammatory response, such as macrophages, neutrophils, and eosinophils release increased amounts of ROS (1,5) exceeding the already reduced tissue antioxidant defences of asthmatic and COPD patients (2).

Expression of muscarinic receptors by human macrophages

Macrophages increase in number and are highly activated in chronic obstructive pulmonary disease (COPD). Muscarinic receptor antagonists inhibit acetylcholine-stimulated release of neutrophilic chemoattractants, suggesting that acetylcholine may regulate macrophage responses. Therefore, expression and function of components of the non-neuronal cholinergic system in monocyte-macrophage cells was investigated. RNA was isolated from monocytes, monocyte-derived macrophages (MDMs), lung and alveolar macrophages from nonsmokers, smokers and COPD patients, and expression of the high-affinity choline transporter, choline acetyltransferase, vesicular acetylcholine transporter and muscarinic receptors (M(1)-M(5)) ascertained using real-time PCR. M(2) and M(3) receptor expression was confirmed using immunocytochemistry. Release of interleukin (IL)-8, IL-6 and leukotriene (LT)B(4) were measured by ELISA or EIA. All monocyte-macrophage cells expressed mRNA for components of the non-neuronal cholinergic system. Lung macrophages expressed significantly more M(1) mRNA compared with monocytes, and both lung macrophages and alveolar macrophages expressed the highest levels of M(3) mRNA. Expression of M(2) and M(3) protein was confirmed in MDMs and lung macrophages. Carbachol stimulated release of LTB(4) from lung macrophages (buffer 222.3 ± 75.1 versus carbachol 1,118 ± 622.4 pg · mL(-1); n = 15, p<0.05) but not IL-6 or IL-8. LTB(4) release was attenuated by the M(3) antagonist, 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (4-DAMP; half maximal effective concentration 5.2 ± 2.2 nM; n = 9). Stimulation of macrophage M(3) receptors promotes release of LTB(4), suggesting that anti-muscarinic agents may be anti-inflammatory.

Inter-institutional pathology consultations for breast cancer: impact on clinical oncology therapy recommendations

Background

Despite recommendations favouring review of cancer pathology specimens for patients being treated at an institution other than the one that produced the initial pathology report, data regarding discordance rates and their potential clinical impact remain limited, particularly for breast cancer. At the QEII Health Sciences Centre in Halifax, Nova Scotia, it was routine practice to review histopathology when patients referred for adjuvant therapy had undergone their breast cancer surgery and pathology reporting at another institution. The aim of the present study was to determine the rate and clinical impact of discordance in inter-institutional pathology consultations for breast cancer in Nova Scotia.

Methods

We conducted a retrospective review of 100 randomly selected inter-institutional pathology consultations for breast cancer patients referred to the QEII in 2004. Cases were categorized as having either no discordance, discordance with no clinical impact, or discordance with potential for clinical impact. Cases with potential clinical impact were independently reviewed by 2 medical oncologists and 2 radiation oncologists, and the discordances were rated as having high, medium, or no clinical impact.

Results

The study cohort consisted of 93 cases that met the inclusion criteria. Of these 93 cases, 6 had no discordance, 7 had discordance with no clinical impact, and 80 had discordance with potential for clinical impact. Overall, 10 cases (11%) were rated as having either high or medium clinical impact, with agreement on the clinical impact ratings by oncologist reviewers in the same specialty. The remaining cases had either no clinical impact or disagreement on the clinical impact rating.

Conclusions

Inter-institutional pathology consultations for breast cancer in Nova Scotia identified discordant findings with potential clinical impact as determined by oncologist reviewers. Further evaluation of inter-institutional pathology consultations and the impact on clinical decision-making is warranted.

Retail sales of inhalation devices in European countries: so much for a global policy

OBJECTIVE

To evaluate the retail sales of pressurised metered-dose inhalers (pMDIs), dry-powder inhalers (DPIs) and liquids for nebulisation in 16 European countries.

METHODS

Retail sales data relating to pMDIs, DPIs and liquids for nebulisation delivering short- and long-acting bronchodilators, corticosteroids and combinations between 2002 and 2008 were obtained from the IMS sales database. The IMS database ensured that wholesalers' stock sales accurately matched that of retail pharmacies and included purchases by panel pharmacies directly from pharmaceutical manufacturers, specialist wholesalers and distribution cooperatives.

RESULTS

Mean inhaler retail sales (expressed as percentages of total sales) were 47.5% for pMDIs, 39.5% for DPIs and 13% for nebulisers. The distribution of inhaler sales differed significantly between the countries with pMDI sales greatest in the United Kingdom and Hungary compared to other countries, where DPI sales prevailed. Sales of nebulisation liquids were high in Italy. The pMDI was the most frequently prescribed inhaler for bronchodilators. In contrast, retail sales of DPIs were similar to those of pMDIs for inhaled corticosteroids, and higher in the case of inhalers with combined long-acting β(2)-agonist and corticosteroid.

CONCLUSION

We found a high degree of variability in inhaler prescription between European countries. Differing health policies, costs, health insurance issues, pharmaceutical/commercial aspects and prescribers' and patients' preferences may explain this variation. We suggest a need for more uniform, outcome-led inhaler prescribing practice across Europe to improve the efficacy and cost effectiveness of the treatment of obstructive airways diseases.

Effects of formoterol and salmeterol on cytokine release from monocyte-derived macrophages

Pulmonary macrophages are a target for inhaled therapies. Combinations of long-acting beta(2)-agonists (LABA) and glucocorticosteroids have been developed for asthma and chronic obstructive pulmonary disease (COPD). This study examined two LABA, salmeterol and formoterol, and the glucocorticosteroid, budesonide, on cytokine release from monocyte-derived macrophages (MDM) to determine whether anti-inflammatory effects observed in patients are due to inhibition of macrophages. MDM were incubated in the absence or presence of LABA or budesonide prior to stimulation with lipopolysaccharide (LPS). Tumour necrosis factor (TNF)-alpha, granulocyte macrophage-colony stimulating factor (GM-CSF) and CXC chemokine ligand (CXCL)8 were measured by ELISA. Formoterol and salmeterol inhibited LPS-stimulated release of TNF-alpha (mean effective concentration (EC(50)) 2.4+/-1.8 and 3.5+/-2.7 nM, respectively; n = 11-16), GM-CSF (EC(50) 24.6+/-2.1 and 52.4+/-40.8 nM, respectively, n = 11-12) but not CXCL8 from LPS-stimulated MDM. Budesonide inhibited release of all three cytokines (EC(50) TNF-alpha: 1.2+/-0.4 nM; GM-CSF: 0.4+/-0.2 nM; CXCL8: 0.4+/-0.1 nM; n = 3-4). Formoterol but not salmeterol elevated cAMP in these cells. These effects were attenuated by beta-adrenoceptor antagonists, propranolol and ICI118551. Salmeterol (10(-7) M) also inhibited formoterol-induced cAMP and formoterol-mediated attenuation of cytokine release. Combining budesonide (0.3 nM) with formoterol, inhibited TNF-alpha release additively. LABA may inhibit inflammatory cytokine release from macrophages in a cAMP-independent manner and act additively with budesonide.

Defective macrophage phagocytosis of bacteria in COPD

Exacerbations of chronic obstructive pulmonary disease (COPD) are an increasing cause of hospitalisations and are associated with accelerated progression of airflow obstruction. Approximately half of COPD exacerbations are associated with bacteria and many patients have lower airways colonisation. This suggests that bacterial infection in COPD could be due to reduced pathogen removal. This study investigated whether bacterial clearance by macrophages is defective in COPD. Phagocytosis of fluorescently labelled polystyrene beads and Haemophillus influenzae and Streptococcus pneumoniae by alveolar macrophages and monocyte-derived macrophages (MDM) was assessed by fluorimetry and flow cytometry. Receptor expression was measured by flow cytometry. Alveolar macrophages and MDM phagocytosed polystyrene beads similarly. There was no difference in phagocytosis of beads by MDM from COPD patients compared with cells from smokers and nonsmokers. MDM from COPD patients showed reduced phagocytic responses to S. pneumoniae and H. influenzae compared with nonsmokers and smokers. This was not associated with alterations in cell surface receptor expression of toll-like receptor (TLR)2, TLR4, macrophage receptor with collagenous structure, cluster of differentiation (CD)163, CD36 or mannose receptor. Budesonide, formoterol or azithromycin did not suppress phagocytosis suggesting that reduced responses in COPD MDM were not due to medications. COPD macrophage innate responses are suppressed and may lead to bacterial colonisation and increased exacerbation frequency.

Association of increased CCL5 and CXCL7 chemokine expression with neutrophil activation in severe stable COPD

BACKGROUND

Increased numbers of activated neutrophils have been reported in the bronchial mucosa of patients with stable chronic obstructive pulmonary disease (COPD), particularly in severe disease.

OBJECTIVES

To investigate the expression of neutrophilic chemokines and adhesion molecules in bronchial biopsies from patients with stable COPD of different severity (GOLD stages I-IV) compared with age-matched control subjects, smokers with normal lung function and never smokers.

METHODS

The expression of CCL5, CXCL1, 5, 6, 7 and 8, CXCR1, CXCR2, CD11b and CD44 was measured in the bronchial mucosa using immunohistochemistry, confocal immunofluorescence, real-time quantitative polymerase chain reaction (RT-QPCR) and Western blotting (WB).

RESULTS

The numbers of CCL5+ epithelial cells and CCL5+ and CXCL7+ immunostained cells were increased in the bronchial submucosa of patients with stable severe COPD compared with control never smokers and smokers with normal lung function. This was also confirmed at the level of mRNA expression. The numbers of CCL5+ cells in the submucosa of patients with COPD were 2-15 times higher than any other chemokines. There was no correlation between the number of these cells and the number of neutrophils in the bronchial submucosa. Compared with control smokers, the percentage of neutrophils co-expressing CD11b and CD44 receptors was significantly increased in the submucosa of patients with COPD.

CONCLUSION

The increased expression of CCL5 and CXCL7 in the bronchial mucosa of patients with stable COPD, together with an increased expression of extracellular matrix-binding receptors on neutrophils, may be involved in the pathogenesis of COPD.

T helper type 17-related cytokine expression is increased in the bronchial mucosa of stable chronic obstructive pulmonary disease patients

There are increased numbers of activated T lymphocytes in the bronchial mucosa of stable chronic obstructive pulmonary disease (COPD) patients. T helper type 17 (Th17) cells release interleukin (IL)-17 as their effector cytokine under the control of IL-22 and IL-23. Furthermore, Th17 numbers are increased in some chronic inflammatory conditions. To investigate the expression of interleukin (IL)-17A, IL-17F, IL-21, IL-22 and IL-23 and of retinoic orphan receptor RORC2, a marker of Th17 cells, in bronchial biopsies from patients with stable COPD of different severity compared with age-matched control subjects. The expression of IL-17A, IL-17F, IL-21, IL-22, IL-23 and RORC2 was measured in the bronchial mucosa using immunohistochemistry and/or quantitative polymerase chain reaction. The number of IL-22(+) and IL-23(+) immunoreactive cells is increased in the bronchial epithelium of stable COPD compared with control groups. In addition, the number of IL-17A(+) and IL-22(+) immunoreactive cells is increased in the bronchial submucosa of stable COPD compared with control non-smokers. In all smokers, with and without disease, and in patients with COPD alone, the number of IL-22(+) cells correlated significantly with the number of both CD4(+) and CD8(+) cells in the bronchial mucosa. RORC2 mRNA expression in the bronchial mucosa was not significantly different between smokers with normal lung function and COPD. Further, we report that endothelial cells express high levels of IL-17A and IL-22. Increased expression of the Th17-related cytokines IL-17A, IL-22 and IL-23 in COPD patients may reflect their involvement, and that of specific IL-17-producing cells, in driving the chronic inflammation seen in COPD.

The airway vasculature: recent advances and clinical implications

It is increasingly recognised that the airway circulation plays an important role in airway diseases, either through a change in blood flow or through microvascular leakage. Most of the information available regarding the anatomy and physiology of bronchial blood flow and its regulation has necessarily derived from animal studies. However, there have recently been important advances in understanding airway blood flow in airway disease in humans through the development of non-invasive methods and in the quantification of microvascular leakage using plasma markers. These studies have shown that bronchial blood flow is increased in patients with asthma but not in those with chronic obstructive pulmonary disease, confirming previous pathology investigations. Changes in bronchial blood flow may in part reflect the generation of new vascular vessels, a process known as "angiogenesis" which is caused by airway inflammation. Angiogenesis and the resulting plasma leak affect airway physiology, drug clearance and its bioavailability. This review discusses the anatomy, physiology and regulation of bronchial blood flow in the normal and diseased lung, In addition, it analyses the effect of current medical treatment and discusses the potential use of new anti-angiogenesis medications. The development of non-invasive assessment of bronchial blood flow and the study of angiogenesis have provided a tool to investigate airway physiology in vivo; these advances will contribute to a better understanding of inflammatory airway diseases as well as the implication of these findings to management.

Intrinsic asthma: not so different from allergic asthma but driven by superantigens?

The mechanisms of intrinsic or non-allergic asthma remain uncertain as allergens have no obvious role in driving the inflammatory process in the airways. However, IgE synthesis occurs in the airways, despite negative skin prick tests and serum-specific IgE. Furthermore, the inflammatory process in the airways is very similar between allergic and non-allergic asthma, with increased T-helper type 2 (Th2) cells, mast cell activation and infiltration of eosinophils. This pattern of inflammation is associated with a similar expression of inflammatory mediators, including Th2 cytokines and eosinophilotactic chemokines. There is increasing evidence that microbial superantigens, particularly Staphylococcal enterotoxins are important in amplifying inflammation in atopic dermatitis and chronic rhinosinusitis, in atopic and non-atopic patients. Superantigens may also be important in intrinsic asthma as airway epithelial cells may be colonized by Staphylococci and other superantigen-producing microbes. Superantigens produced locally in the airways may lead to class switching of local B cells, resulting in polyclonal IgE production in the airways and also specific IgE against the superantigen (which functions as a 'superallergen'). This leads to sensitization of mast cells, which can be activated by the usual asthma triggers, such as exercise. Superantigens also cause clonal expansion of T cells, resulting in increased Th2 cells and CD8(+) cells, while suppressing regulatory T cells. Superantigens may also reduce responsiveness to corticosteroids, resulting in more severe asthma. Finally, cytotoxic autoantibodies may also be implicated as IgG antibodies directed against epithelial proteins, such as cytokeratin-18, have been detected in intrinsic asthma, possibly as a result of epithelial damage and this may make epithelial cells more susceptible to microbial colonization. The therapeutic implications are that antibodies against local IgE and microbial superantigens or antibiotic therapy to eradicate the relevant superantigen-producing microorganisms may improve the efficacy of conventional therapy with corticosteroids.

Calcium, calcium channel blockade and airways function

This review will highlight recent advances in understanding the physiological role of calcium and effects of calcium channel blockers on pathogenetic factors in asthma, including airway smooth muscle contraction, mast cell degranulation and mucus secretion. A review of clinical studies with calcium channel blockers in asthma will also be presented.

Effect of low-dose theophylline plus beclometasone on lung function in smokers with asthma: a pilot study

Smoking is common in asthma and is associated with worse asthma control and a reduced therapeutic response to corticosteroids. The present authors hypothesised that treating smokers with asthma with low-dose theophylline added to inhaled corticosteroids would enhance steroid sensitivity and thereby improve lung function and symptoms. In a double-blind, parallel group exploratory trial, 68 asthmatic smokers were randomised to one of three treatments for 4 weeks: inhaled beclometasone (200 microg day(-1)), theophylline (400 mg day(-1)) or both treatments combined. Outcome measures included change in lung function and Asthma Control Questionnaire (ACQ) scores. At 4 weeks, theophylline added to inhaled beclometasone produced an improvement in peak expiratory flow (39.9 L min(-1), 95% confidence intervals (CI) 10.9-68.8) and ACQ score (-0.47, 95% CI -0.91- -0.04) and a borderline improvement in pre-bronchodilator forced expiratory volume in one second (mean difference 165 mL, 95% CI -13-342) relative to inhaled corticosteroid alone. Theophylline alone improved the ACQ score (-0.55, 95% CI -0.99- -0.11), but not lung function. In the present pilot study, the combination of low-dose theophylline and inhaled beclometasone produced improvements in both lung function and symptoms in a group of smokers with asthma. Larger trials are required to extend and confirm these findings.

Low-dose theophylline enhances the anti-inflammatory effects of steroids during exacerbations of COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterised by an abnormal inflammatory response mainly to cigarette smoke that flares up during exacerbations of the disease (ECOPD). Reduced activity of histone deacetylases (HDAC) contributes to enhanced inflammation in stable COPD. It was hypothesised that HDAC activity is further reduced during ECOPD and that theophylline, an HDAC activator, potentiates the anti-inflammatory effect of steroids in these patients. A study was performed to investigate HDAC activity during ECOPD and the effects of theophylline on the anti-inflammatory effects of steroids in a randomised single-blind controlled study.

METHODS

35 patients hospitalised with ECOPD and treated according to international guidelines (including systemic steroids) were randomised to receive or not to receive low-dose oral theophylline (100 mg twice daily). Before treatment and 3 months after discharge, HDAC and nuclear factor-kappaB (NF-kappaB) activity in sputum macrophages, the concentration of nitric oxide in exhaled air (eNO) and total antioxidant status (TAS), tumour necrosis factor alpha (TNFalpha), interleukin (IL)-6 and IL8 levels in sputum supernatants were measured.

RESULTS

Patients receiving standard therapy showed decreased NF-kappaB activity, eNO concentration and sputum levels of TNFalpha, IL6 and IL8, as well as increased TAS during recovery of ECOPD, but HDAC activity did not change. The addition of low-dose theophylline increased HDAC activity and further reduced IL8 and TNFalpha concentrations.

CONCLUSIONS

During ECOPD, low-dose theophylline increases HDAC activity and improves the anti-inflammatory effects of steroids.

TRIAL REGISTRATION NUMBER

NCT00671151.

Real-time measurement of particulate matter deposition in the lung

Air pollution and cigarette smoke are recognized health risks. A method was developed for the measurement of the deposition fraction (DF) of polydisperse particulate matter (PM) in human airways. Ten normal volunteers [three females, age range 18-67 years, mean age (SD) 43.9 (14)] made single breath exhalations after inhalation to total lung capacity. The exhaled breath was diverted to a multichannel laser diffraction chamber where the particulate profiler measured 0.3 - 1.0-microm particles. DF was inversely related to expiration flow-rate, 0.69 (0.02) at 4 l min-1 and 0.5 (0.01) at 13 l min-1, respectively (p<0.05), and was influenced by the inhalation flow-rate [0.70 (0.02) at 3 l min-1 and 0.59 (0.02) at 13 l min-1, respectively (p<0.05)], while no differences were found between nasal and oral inhalation (0.68 (0.05) versus 0.67 (0.06), p>0.05). Higher breath holding times were associated with elevated DF [0.74 (0.02) at 20 s, and 0.62 (0.05) without breath holding (p<0.01)]. When the expiratory flow was controlled and the breath hold time standardized, DF was reproducible (CV = 4.85%). PM can be measured in the exhaled breath and its DF can be quantified using a portable device. These methods may be useful in studies investigating the health effects of air pollution and tobacco smoke.

Feasibility and interpretation of FE(NO) measurements in asthma patients in general practice

BACKGROUND

Exhaled NO (FE(NO)) is a useful biomarker for the monitoring of asthma control and response to therapy. However, there is a lack of data on FE(NO) levels and their interpretation in Primary Care asthma population depending on their treatment and smoking habit. Besides, the majority of current FE(NO) tests have been done by stationary chemiluminescence analysers whose use is limited to research laboratories.

METHODS

FE(NO) measurements by the novel hand-held NO monitoring device (NIOX MINO) were made in 96 asthma patients (32 males, mean age 53+/-12) at five local General Practices during their scheduled 15-20 min visits for lung function assessment.

RESULTS

Success rate was 78% and the intra-subject coefficient of variation was 8.7%. Inhaled corticosteroid treatment had an overall reducing effect on the FE(NO) value (30.5 [19.8-49.8]) vs. patients not on the ICS (26.5 [19-94]) (p<0.044). FE(NO) levels in the ICS treated current or ex-smokers group of patients were still significantly above the normal values (p<0.0001). FE(NO) levels were similar in patients receiving ICS whether there were current, ex-smokers or non-smokers. The highest FE(NO) levels (94 [15.8-151]) were found in asthmatic current smokers and not receiving treatment with ICS. The most "normalised" FE(NO) levels (35.3 [13.5-35.3]) were seen in ex-smokers.

CONCLUSIONS

FE(NO) measurements performed with a new hand-held monitoring device are reproducible and feasible in General Practice in the majority of patients of different ages and asthma severities. A high percentage of patients with different severities of asthma and regardless of their treatment with ICS and current smoking habit (current and/or ex-smokers) had highly elevated FE(NO) values, suggesting that their current therapy was possibly insufficient to control the underlying degree of airway inflammation and asthma symptoms.

Global strategy for asthma management and prevention: GINA executive summary

Asthma is a serious health problem throughout the world. During the past two decades, many scientific advances have improved our understanding of asthma and ability to manage and control it effectively. However, recommendations for asthma care need to be adapted to local conditions, resources and services. Since it was formed in 1993, the Global Initiative for Asthma, a network of individuals, organisations and public health officials, has played a leading role in disseminating information about the care of patients with asthma based on a process of continuous review of published scientific investigations. A comprehensive workshop report entitled "A Global Strategy for Asthma Management and Prevention", first published in 1995, has been widely adopted, translated and reproduced, and forms the basis for many national guidelines. The 2006 report contains important new themes. First, it asserts that "it is reasonable to expect that in most patients with asthma, control of the disease can and should be achieved and maintained," and recommends a change in approach to asthma management, with asthma control, rather than asthma severity, being the focus of treatment decisions. The importance of the patient-care giver partnership and guided self-management, along with setting goals for treatment, are also emphasised.

Relative corticosteroid insensitivity of alveolar macrophages in severe asthma compared with non-severe asthma

BACKGROUND

About 5-10% of patients with asthma suffer from poorly controlled disease despite corticosteroid (CS) treatment, which may indicate the presence of CS insensitivity. A study was undertaken to determine whether relative CS insensitivity is present in alveolar macrophages from patients with severe asthma and its association with p38 mitogen-activated protein kinase (MAPK) activation and MAPK phosphatase-1 (MKP-1).

METHODS

Fibreoptic bronchoscopy and bronchoalveolar lavage (BAL) were performed in 20 patients with severe asthma and 19 with non-severe asthma and, for comparison, in 14 normal volunteers. Alveolar macrophages were exposed to lipopolysaccharide (LPS, 10 mug/ml) and dexamethasone (10(-8) and 10(-6) M). Supernatants were assayed for cytokines using an ELISA-based method. p38 MAPK activity and MKP-1 messenger RNA expression were assayed in cell extracts.

RESULTS

The inhibition of LPS-induced interleukin (IL)1beta, IL6, IL8, monocyte chemotactic protein (MCP)-1 and macrophage inflammatory protein (MIP)-1alpha release by dexamethasone (10(-6) M) was significantly less in macrophages from patients with severe asthma than in macrophages from patients with non-severe asthma. There was increased p38 MAPK activation in macrophages from patients with severe asthma. MKP-1 expression induced by dexamethasone and LPS, expressed as a ratio of LPS-induced expression, was reduced in severe asthma.

CONCLUSION

Alveolar macrophages from patients with severe asthma demonstrate CS insensitivity associated with increased p38 MAPK activation that may result from impaired inducibility of MKP-1.

Outcomes for COPD pharmacological trials: from lung function to biomarkers

The American Thoracic Society/European Respiratory Society jointly created a Task Force on "Outcomes for COPD pharmacological trials: from lung function to biomarkers" to inform the chronic obstructive pulmonary disease research community about the possible use and limitations of current outcomes and markers when evaluating the impact of a pharmacological therapy. Based on their review of the published literature, the following document has been prepared with individual sections that address specific outcomes and markers, and a final section that summarises their recommendations.

Importance of inhaler devices in the management of airway disease

The delivery of drugs by inhalation is an integral component of asthma and chronic obstructive pulmonary disease (COPD) management. However, even with effective inhaled pharmacological therapies, asthma, particularly, remains poorly controlled around the world. The reasons for this are manifold, but limitations of treatment guidelines in terms of content, implementation and relevance to everyday clinical life, including insufficient patient education, access to health care and cost of medication as well as poor inhaler technique are likely to contribute. Considering that inhalation therapy is a cornerstone in asthma and COPD management, little advice is provided in the guidelines regarding inhaler selection. The pressurised metered dose inhaler (pMDI) is still the most frequently prescribed device worldwide, but even after repeated tuition many patients fail to use it correctly. In addition, the correct technique can be lost over time. Although several improvements in pMDIs such as a change in the propellant and actuation have resulted in improvements in lung deposition, many dry powder inhalers (DPIs) are easier to use. However, these devices also have limitations such as dependency of drug particle size on flow rate and loss of the metered dose if the patient exhales through the device before inhaling. Improvements in using inhalation devices more efficiently, in inhaler design for supporting patient compliance, and advances in inhaler technology to assure drug delivery to the lungs, have the potential to improve asthma and COPD management and control. New and advanced devices are considered being helpful to minimise the most important problems patients have with current DPIs.

Lung delivery studies using siRNA conjugated to TAT(48-60) and penetratin reveal peptide induced reduction in gene expression and induction of innate immunity

The therapeutic application of siRNA shows promise as an alternative approach to small-molecule inhibitors for the treatment of human disease. However, the major obstacle to its use has been the difficulty in delivering these large anionic molecules in vivo. In this study, we have investigated whether siRNA-mediated knockdown of p38 MAP kinase mRNA in mouse lung is influenced by conjugation to the nonviral delivery vector cholesterol and the cell penetrating peptides (CPP) TAT(48-60) and penetratin. Initial studies in the mouse fibroblast L929 cell line showed that siRNA conjugated to cholesterol, TAT(48-60), and penetratin, but not siRNA alone, achieved a limited reduction of p38 MAP kinase mRNA expression. Intratracheal administration of siRNA resulted in localization within macrophages and scattered epithelial cells and produced a 30-45% knockdown of p38 MAP kinase mRNA at 6 h. As with increasing doses of siRNA, conjugation to cholesterol improved upon the duration but not the magnitude of mRNA knockdown, while penetratin and TAT(48-60) had no effect. Importantly, administration of the penetratin or TAT(48-60) peptides alone caused significant reduction in p38 MAP kinase mRNA expression, while the penetratin-siRNA conjugate activated the innate immune response. Overall, these studies suggest that conjugation to cholesterol may extend but not increase siRNA-mediated p38 MAP kinase mRNA knockdown in the lung. Furthermore, the use of CPP may be limited due to as yet uncharacterized effects upon gene expression and a potential for immune activation.

Scientific rationale for using a single inhaler for asthma control

Clinical trials have recently demonstrated that using a budesonide/formoterol combination inhaler as regular maintenance treatment twice daily but also as a rescue therapy for breakthrough symptoms can provide more effective control of asthma, particularly in reducing exacerbations, than using a short-acting beta2-agonist or formoterol as rescue therapy. This suggests that the corticosteroid component of the combination therapy plays an important role in rescue therapy. Formoterol as a rescue therapy is effective in relieving symptoms by relaxing airway smooth muscle but is also likely to have important inhibitory effects on mast cells, plasma exudation and neutrophilic inflammation. Inhaled corticosteroids have much more rapid suppressing effects on airway inflammation than previously recognised and the increased dose used as rescue therapy may prevent the increase in airway inflammation that occurs during the evolution of an exacerbation, thus preventing its development. It is likely that the molecular interactions between beta2-agonists and corticosteroids also enhance the effect of the combination therapy as rescue therapy. There is now a strong scientific rationale for single inhaler therapy in asthma, but more research is now needed to better understand the mechanisms involved.

Exacerbations of chronic obstructive pulmonary disease

Exacerbations of chronic obstructive pulmonary disease are of major importance in terms of their prolonged detrimental effects on patients, the acceleration in disease progression and high healthcare costs. There is still debate about how exacerbations should be defined and graded, and their mechanisms are poorly understood. The major causal agents are either bacteria or viral infections, or a combination of the two. Noninfective causes include air pollution and pulmonary embolus but, in some patients, no cause is identified. Exacerbations represent an increase in the inflammation that is present in the stable state, with increased numbers of inflammatory cells (particularly neutrophils), cytokines, chemokines and proteases in the airways, and increased concentrations of certain cytokines and C-reactive protein in the blood. There are presently no reliable biomarkers with which to predict exacerbations. Exacerbations have a long-lasting adverse influence on health status. High doses of bronchodilators are the mainstay of treatment and systemic corticosteroids have some benefit. The routine use of antibiotics remains controversial but they are of benefit with exacerbations of a bacterial origin. Noninvasive ventilation is beneficial in preventing the need for intubation and its important complications but it is not certain whether its use in stable patients prevents exacerbations. Although important advances have been made, more effective treatments are needed in the future for prevention and treatment of exacerbations.