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Following inhalation exposure to organophosphorus nerve agents, symptoms rapidly develop and severe respiratory symptoms, such as bronchorrhea and bronchoconstriction are the leading causes of lethality. Nerve agent-induced lung injury is little investigated and the standard treatment for symptomatic relief targets the enzyme acetylcholinesterase and muscarinic acetylcholine and GABAergic receptors. In the present study, cellular responses in lung tissue during the acute (40 min) and extended phase (24 h) following severe exposure to the nerve agent VX have been investigated using an ex vivo rat precision-cut lung slice model including electrostimulation to induce a cholinergic response. Changes in protein amount, cell viability, together with, inflammatory and oxidative stress markers have been determined in both the lung tissue and incubation medium. During the acute phase, VX caused significantly increased airway contraction and decreased airway relaxation. Five micromolar of VX did not affect the sample protein levels and cell viability in lung tissue. Among seven markers of cellular responses investigated in the lung tissue, increased levels of heme oxygenase-1 and matrix metalloproteinase-9 together with decreased levels of glutathione in the incubation medium were observed in the acute phase following VX-exposure compared to electrostimulation only. No difference in cellular response was observed following VX-exposure for 24 h compared to the air control. In comparison, LPS-exposure resulted in time-dependent changes in all markers of inflammation and oxidative response. In conclusion, the present study demonstrated VX-specific patterns of oxidative responses in the lung, as well as, signs of inflammatory response and remodelling of extracellular matrix. These potential mechanisms of tissue injury should be further investigated for their potential as additional therapeutic targets during the acute phase of intoxication. • Nerve agent specific responses were shown during the acute phase of exposure. • Oxidative stress was verified by changed glutathione and heme oxygenase-1 levels. • Increased levels of matrix metalloproteinase-9 indicate tissue remodelling. [ABSTRACT FROM AUTHOR]

We have investigated the potential of two complex mineral particles (feldspar and mylonite), quartz (Min-U-Sil), and suspended particulate matter (SRM-1648) (SPM) from urban air to induce inflammatory cytokine responses in primary rat alveolar type 2 cells and alveolar macrophages, and the involvement of cellular formation of free radicals in these responses. All particle types induced an increased release of interleukin (IL)-6 and macrophage inflammatory protein (MIP)-2 from type 2 cells. Diphenyleneiodonium chloride (DPI), a selective inhibitor of NADPH-oxidase, reduced the IL-6 and MIP-2 responses to quartz, SPM and mylonite. N-(3-[Aminomethyl] benzyl) acetamidine (1400W), a selective inhibitor of inducible nitric oxide synthase (iNOS), significantly reduced the Il-6 response to SPM and feldspar in the type 2 cells. The macrophages displayed significantly increased TNF-α and MIP-2 release upon exposure to quartz or SPM. Here, DPI significantly reduced the tumor necrosis factor (TNF)-α and MIP-2 responses to quartz, and the MIP-2 response to SPM. No significant effect of 1400 W was detected in the alveolar macrophages. The role of particle-induced cellular generation of free radicals in lung cytokine responses was further elucidated in mice that lacked either NADPH-oxidase or iNOS as well as in wild-type (wt) mice. All particles were able to elicit increased cytokine levels in the bronchoalveolar lavage (BAL) fluid of the mice, although the levels depended on particle type. The NADPH-oxidase knockout (KO) mice demonstrated a significantly lower IL-6 and MIP-2 responses to SPM compared to their respective wt mice. The iNOS KO mice displayed significantly reduced IL-6, TNF-α, and MIP-2 responses to SPM. The overall results indicate the involvement of cellular free-radical formation in the pulmonary cytokine responses to particles of varying composition. [ABSTRACT FROM AUTHOR]

Inhalation of high concentrations of sulfur dioxide (SO 2 ) affects the lungs and can be immediately dangerous to life. We examined the development of acute and long-term effects after exposure of SO 2 in Sprague-Dawley rats, in particular inflammatory responses, airway hyperresponsiveness (AHR) and lung fibrosis. Animals were subjected to a single exposure of 2200 ppm SO 2 during 10 min and treated with a single dose of the anti-inflammatory corticosteroid dexamethasone 1 h following exposure. Exposed rats showed labored breathing, decreased body-weight and an acute inflammation with neutrophil and macrophage airway infiltrates 5 h post exposure. The acute effects were characterized by bronchial damage restricted to the larger bronchi with widespread injured mucosal epithelial lining. Rats displayed hyperreactive airways 24 h after exposure as indicated by increased methacholine-induced respiratory resistance. The inflammatory infiltrates remained in lung tissue for at least 14 days but at the late time-point the dominating granulocyte types had changed from neutrophils to eosinophils. Analysis of immunoregulatory and pro-inflammatory cytokines in serum and airways implicated mixed macrophage phenotypes (M1/M2) and T helper cell activation of both T H 1 and T H 2 subtypes. Increased expression of the pro-fibrotic cytokine TGFβ1 was detected in airways 24 h post exposure and remained increased at the late time-points (14 and 28 days). The histopathology analysis confirmed a significant collagen deposition 14 days post exposure. Treatment with dexamethasone significantly counteracted the acute inflammatory response but was insufficient for complete protection against SO 2 -induced adverse effects, i.e. treatment only provided partial protection against AHR and the long-term fibrosis. [ABSTRACT FROM AUTHOR]

Chlorine (Cl 2 ) causes tissue damage and a neutrophilic inflammatory response in the airways manifested by pronounced airway hyperreactivity (AHR). The importance of early anti-inflammatory treatment has previously been addressed. In the previous study, both high-dose and low-dose of dexamethasone (DEX) decreased the risk of developing delayed effects, such as persistent lung injuries, while only high-dose treatment could significantly counteract acute-phase effects. One aim of this study was to evaluate whether a low-dose of DEX in combination with the antioxidant N -acetyl cysteine (NAC) and if different treatments (Triptolide, Reparixin and Rolipram) administered 1 h after Cl 2 -exposure could improve protection against acute lung injury in Cl 2 -exposed mice. BALB/c mice were exposed to 300 ppm Cl 2 during 15 min. Assessment of AHR and inflammatory cells in bronchoalveolar lavage was analyzed 24 h post exposure. Neither of DEX nor NAC reduced the AHR and displayed only minor effects on inflammatory cell influx when given as separate treatments. When given in combination, a protective effect on AHR and a significant reduction in inflammatory cells (neutrophils) was observed. Neither of triptolide, Reparixin nor Rolipram had an effect on AHR but Triptolide had major effect on the inflammatory cell influx. Treatments did not reduce the concentration of either fibrinogen or plasminogen activator inhibitor-1 in serum, thereby supporting the theory that the inflammatory response is not solely limited to the lung. These results provide a foundation for future studies aimed at identifying new concepts for treatment of chemical-induced lung injury. Studies addressing combination of anti-inflammatory and antioxidant treatment are highly motivated. [ABSTRACT FROM AUTHOR]

Exposure to highly toxic organophosphorus compounds causes inhibition of the enzyme acetylcholinesterase resulting in a cholinergic toxidrome and innervation of receptors in the neuromuscular junction may cause life-threatening respiratory effects. The involvement of several receptor systems was therefore examined for their impact on bronchoconstriction using an ex vivo rat precision-cut lung slice (PCLS) model. The ability to recover airways with therapeutics following nerve agent exposure was determined by quantitative analyses of muscle contraction. PCLS exposed to nicotine resulted in a dose-dependent bronchoconstriction. The neuromuscular nicotinic antagonist tubocurarine counteracted the nicotine-induced bronchoconstriction but not the ganglion blocker mecamylamine or the common muscarinic antagonist atropine. Correspondingly, atropine demonstrated a significant airway relaxation following ACh-exposure while tubocurarine did not. Atropine, the M3 muscarinic receptor antagonist 4-DAMP, tubocurarine, the β 2 -adrenergic receptor agonist formoterol, the Na+-channel blocker tetrodotoxin and the K+ ATP -channel opener cromakalim all significantly decreased airway contractions induced by electric field stimulation. Following VX-exposure, treatment with atropine and the Ca2+-channel blocker magnesium sulfate resulted in significant airway relaxation. Formoterol, cromakalim and magnesium sulfate administered in combinations with atropine demonstrated an additive effect. In conclusion, the present study demonstrated improved airway function following nerve agent exposure by adjunct treatment to the standard therapy of atropine. • Nicotine dose-dependently induced airway contractions. • Receptor modulation affected normal airway function. • Atropine and magnesium sulfate efficiently reversed VX-induced bronchoconstriction. • Other single receptor modulators did not impact on VX-effects. • Therapeutic combinations demonstrated an additive effect. [ABSTRACT FROM AUTHOR]

Abstract: Chlorine is highly irritating when inhaled, and is a common toxic industrial gas causing tissue damage in the airways followed by an acute inflammatory response. In this study, we investigated mechanisms by which chlorine exposure may cause reactive airways dysfunction syndrome (RADS) and we examined the dose-dependency of the development of symptoms. Mice were exposed to 50 or 200ppm Cl2 during a single 15min exposure in a nose-only container. The experiment terminated 2, 6, 12, 24, 48, 72h and 7, 14, 28 and 90 days post exposure. Inflammatory cell counts in bronchoalveolar lavage (BAL), secretion of inflammatory mediators in BAL, occurrence of lung edema and histopathological changes in lung tissue was analyzed at each time-point. Airway hyperresponsiveness (AHR) was studied after 24 and 48h and 7, 14, 28 and 90 days. The results showed a marked acute response at 6h (50ppm) and 12h (200ppm) post exposure as indicated by induced lung edema, increased airway reactivity in both central and peripheral airways, and an airway inflammation dominated by macrophages and neutrophils. The inflammatory response declined rapidly in airways, being normalized after 48h, but inflammatory cells were sustained in lung tissue for at least seven days. In addition, a sustained AHR was observed for at least 28 days. In summary, this mouse model of chlorine exposure shows delayed symptoms of hyperreactive airways similar to human RADS. We conclude that the model can be used for studies aimed at improved understanding of adverse long-term responses following inhalation of chlorine. [Copyright &y& Elsevier]

Abstract: Low-dose exposure of alkylating mustard gas causes long-term respiratory complications characterized by bronchitis and lung fibrosis. In this study, we utilized a mouse model for lung exposure of the nitrogen mustard melphalan, in order to define early and late events in the pathogenesis such as expression of pro-inflammatory cytokines, recruitment of inflammatory cells to airways and late-phase fibrosis. We investigated the roles of different T lymphocyte subsets on the inflammatory response by using knockout mice lacking either the genes expressing T cell receptor (TCR)αβ or TCRγδ, and compared the responsiveness with that of wild type mice and double knockout mice completely deficient in T cells. Exposure to melphalan induced an early burst of the pro-inflammatory cytokines interleukin (IL)-1β, IL-6 and IL-23 in airways, followed by extensive infiltration of neutrophils in the lung tissue and airways within 24h. The acute phase was followed by a sustained lymphocytic response that persisted for at least 14 days with resulting lung fibrosis. Engagement of T lymphocytes, particularly the γδ T cell subset, was crucial both for the acute cytokine and neutrophil response and for the late-phase lung fibrosis as indicated by the lack of response in γδ T cell deficient mice. Our data demonstrate that T lymphocytes play a prominent role in the pathogenesis of long-term lung injuries caused by strong alkylating agents. [Copyright &y& Elsevier]

The effect of lipopolysaccharide inhalation upon lung anandamide levels, anandamide synthetic enzymes and fatty acid amide hydrolase has been investigated. Lipopolysaccharide exposure produced a dramatic extravasation of neutrophils and release of tumour necrosis factor α into the bronchoalveolar lavage (BAL) fluid, which was not accompanied by epithelial cell injury. The treatment, however, did not change significantly the levels of anandamide and the related compound palmitoylethanolamide in the cell-free fraction of the BAL fluid. The activities of the anandamide synthetic enzymes N-acyltransferase and N-acylphosphatidylethanolamine phospholipase D and the activity of fatty acid amide hydrolase in lung membrane fractions did not change significantly following the exposure to lipopolysaccharide. The non-selective fatty acid amide hydrolase inhibitor phenylmethylsulfonyl fluoride was a less potent inhibitor of lung fatty acid amide hydrolase than expected from the literature, and a dose of 30 mg/kg i.p. of this compound, which produced a complete inhibition of brain anandamide metabolism, only partially inhibited the lung metabolic activity. [Copyright &y& Elsevier]

• MOF-808 showed the greatest ability to degrade VX in an alkaline buffer. • In decontamination lotion, MOF-808 provided improved agent absorption during skin decontamination. • MOF-808 resulted in greater decontamination factor compared to the carrier alone. Metal-organic frameworks (MOFs) have shown promising properties for removal of chemical warfare agents, in particular for material decontamination and functionalized fabrics. The MOF-properties could also be beneficial for skin decontamination, especially when exposed to highly toxic and low volatile nerve agents. In such exposures, efficient decontamination is crucial for adequate medical management. In the present study, seven zirconium-based MOFs were evaluated for their ability to degrade VX and subsequently tested in vitro for decontamination of VX on human dermatomed skin. Of the MOFs evaluated, MOF-808 showed the greatest ability to degrade VX in an alkaline buffer with complete degradation of VX within 5 min. PCN-777, Zr-NDC and NU-1000 displayed degradation half-lives of approximately 10 min. When including MOF-808 in a skin friendly carrier with slightly acidic pH, a decreased agent degradation rate was observed, requiring over 24 h to reach complete degradation. In skin decontamination experiments, MOF-808 enhanced the efficacy compared to the carrier alone, essentially by improved agent absorption. Adding MOF-808 to Reactive Skin Decontamination Lotion (RSDL) did not improve the high effectiveness of RSDL alone. The present study showed that including MOF in skin decontamination lotions could be beneficial. Further studies should include optimizing the particulates and formulations. [ABSTRACT FROM AUTHOR]

Background: Differences in the expression of regulatory T cells (Tregs) have been suggested to explain why some smokers develop COPD and some do not. Upregulation of Tregs in response to smoking would restrain airway inflammation and thus the development of COPD; while the absense of such upregulation would over time lead to chronic inflammation and COPD. We hypothesized that-among COPD patients-the same mechanism would affect rate of decline in lung function; specifically, that a decreased expression of Tregs would be associated with a more rapid decline in FEV1.Methods: Bronchoscopy with BAL was performed in 52 subjects recruited from the longitudinal OLIN COPD study; 12 with COPD and a rapid decline in lung function (loss of FEV1 ≥ 60 ml/year), 10 with COPD and a non-rapid decline in lung function (loss of FEV1 ≤ 30 ml/year), 15 current and ex-smokers and 15 non-smokers with normal lung function. BAL lymphocyte subsets were determined using flow cytometry.Results: The proportions of Tregs with regulatory function (FoxP3+/CD4+CD25bright) were significantly lower in COPD subjects with a rapid decline in lung function compared to those with a non-rapid decline (p = 0.019). This result was confirmed in a mixed model regression analysis in which adjustments for inhaled corticosteroid usage, smoking, sex and age were evaluated. No significant difference was found between COPD subjects and smokers or non-smokers with normal lung function.Conclusions: COPD subjects with a rapid decline in lung function had lower proportions of T cells with regulatory function in BAL fluid, suggesting that an inability to suppress the inflammatory response following smoking might lead to a more rapid decline in FEV1. Trial registration Clinicaltrials.gov identifier NCT02729220. [ABSTRACT FROM AUTHOR]

Context: Inhalation of sulfur dioxide (SO2) affects the lungs and exposure to high concentrations can be lethal. The early pulmonary response after inhaled SO2 involves tissue injury, acute neutrophilic lung inflammation and airway hyperresponsiveness (AHR). In rats, long-term pulmonary fibrosis is evident 14 days post-exposure as indicated by analysis of collagen deposition in lung tissue. Early treatment with a single dose of dexamethasone (DEX,10 mg/kg) significantly attenuates the acute inflammatory response in airways. However, this single DEX-treatment is not sufficient for complete protection against SO2-induced injuries. Methods: Female Sprague-Dawley rats exposed to SO2 (2200 ppm, nose-only exposure, 10 min) were given treatments (1, 5 and 23 h after SO2-exposure) with the anti-fibrotic and anti-inflammatory substance Pirfenidone (PFD, 200 mg/kg) or DEX (10 mg/kg) to evaluate whether the inflammatory response, AHR and lung fibrosis could be counteracted. Results: Both treatment approaches significantly reduced the total leukocyte response in bronchoalveolar lavage fluid and suppressed pulmonary edema. In contrast to DEX-treatment, PFD-treatment reduced the methacholine-induced AHR to almost control levels and partially suppressed the acute mucosal damage whereas multiple DEX-treatment was the only treatment that reduced collagen formation in lung tissue. Conclusions: To enable an accurate extrapolation of animal derived data to humans, a detailed understanding of the underlying mechanisms of the injury, and potential treatment options, is needed. The findings of the present study suggest that treatments with the capability to reduce both AHR, the inflammatory response, and fibrosis are needed to achieve a comprehensive mitigation of the acute lung injury caused by SO2. [ABSTRACT FROM AUTHOR]

Inhalation of chlorine (Cl 2 ) may cause oxidative acute lung injury (ALI) characterized by pulmonary edema, pneumonitis, and hyperreactive airways. The aim of the study was to identify possible biomarkers for Cl 2 -induced ALI. Female BALB/c mice were exposed to Cl 2 for 15 min using two protocols 1) concentration-dependent response (25–200 ppm) and 2) time-kinetics (2h–14 days post-exposure). Exposure to 50–200 ppm Cl 2 caused a concentration-dependent inflammatory response with increased expression of IL-1β, IL-6 and CXCL1/KC in bronchoalveolar lavage fluid 2–6 h after exposure which was followed by increased lung permeability and a neutrophilic inflammation 12–24 h post-exposure. The early inflammatory cytokine response was associated with a clear but transient increase of 8-isoprostane, a biomarker for oxidative stress, with its maximum at 2 h after exposure. An increase of 8-isoprostane could also be detected in serum 2 h after exposure to 200 ppm Cl 2 , which was followed by increased levels of IL-6 and CXCL1/KC and signs of increased fibrinogen and PAI-1. Melphalan, a non-oxidizing mustard gas analog, did not increase the 8-isoprostane levels, indicating that 8-isoprostane is induced in airways through direct oxidation by Cl 2 . We conclude that 8-isoprostane represents an early biomarker for oxidative stress in airways and in the blood circulation following Cl 2 -exposure. [ABSTRACT FROM AUTHOR]

We investigated acute and delayed respiratory changes after inhalation exposure to chlorine (Cl 2 ) with the aim to understand the pathogenesis of the long-term sequelae of Cl 2 -induced lung-injury. In a rat model of nose-only exposure we analyzed changes in airway hyperresponsiveness (AHR), inflammatory responses in airways, expression of pro-inflammatory markers and development of lung fibrosis during a time-course from 5 h up to 90 days after a single inhalation of Cl 2 . A single dose of dexamethasone (10 mg/kg) was administered 1 h following Cl 2 -exposure. A 15-min inhalation of 200 ppm Cl 2 was non-lethal in Sprague-Dawley rats. At 24 h post exposure, Cl 2 -exposed rats displayed elevated numbers of leukocytes with an increase of neutrophils and eosinophils in bronchoalveolar lavage (BAL) and edema was shown both in lung tissue and the heart. At 24 h, the inflammasome-associated cytokines IL-1β and IL-18 were detected in BAL. Concomitant with the acute inflammation a significant AHR was detected. At the later time-points, a delayed inflammatory response was observed together with signs of lung fibrosis as indicated by increased pulmonary macrophages, elevated TGF-β expression in BAL and collagen deposition around airways. Dexamethasone reduced the numbers of neutrophils in BAL at 24 h but did not influence the AHR. Inhalation of Cl 2 in rats leads to acute respiratory and cardiac changes as well as pulmonary inflammation involving induction of TGF-β1. The acute inflammatory response was followed by sustained macrophage response and lack of tissue repair. It was also found that pathways apart from the acute inflammatory response contribute to the Cl 2 -induced respiratory dysfunction. [ABSTRACT FROM AUTHOR]

In mass casualty incidents including hazardous chemical skin exposure, decontamination is the primary intervention to avoid systemic uptake of the toxic compound. The protocol needs to be both simple and efficient to enable a rapid response and avoid delay of patient management. In the present study, decontamination strategies included in the initial operational response were evaluated following human skin exposure in vitro to four different contaminants. Results demonstrated that the efficacy of selected decontamination procedures was highly dependent on the chemical contaminant used. Dry removal of the sulfur mustard simulant methyl salicylate prior to wet decontamination was found beneficial compared to wet decontamination alone. Rapidly initiated wet decontamination was more efficient compared to dry and wet removal of the industrial chemical 2-butoxyethanol and the nerve agent tabun. Following VX-exposure, all wet decontamination procedures resulted in increased agent penetration compared to the control. In conclusion, challenges in establishing simple and efficient decontamination procedures for a broad-spectrum of chemicals have been demonstrated. The impact of including a dry removal step during decontamination was evidently agent specific. Despite the variation in efficacy, immediately initiated dry removal may facilitate patient management until wet decontamination resources are available and to reduce the risk of secondary contamination. • The efficacy of evaluated decontamination procedures was highly agent dependent. • Decontamination initiated by dry removal was only beneficial for methyl salicylate. • Rapidly initiated wet decontamination was useful for tabun and 2-butoxyethanol. • Following VX-exposure, all procedures increased the agent skin penetration. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the inflammatory and immunological responses in airways and lung-draining lymph nodes (LDLNs), following lung exposure to iron oxide (hematite) nanoparticles (NPs). The responses to the hematite NPs were evaluated in both healthy non-sensitized mice, and in sensitized mice with an established allergic airway disease. The mice were exposed intratracheally to either hematite NPs or to vehicle (PBS) and the cellular responses were evaluated on days 1, 2, and 7, post-exposure. Exposure to hematite NPs increased the numbers of neutrophils, eosinophils, and lymphocytes in the airways of non-sensitized mice on days 1 and 2 post-exposure; at these time points the number of lymphocytes was also elevated in the LDLNs. In contrast, exposing sensitized mice to hematite NPs induced a rapid and unspecific cellular reduction in the alveolar space on day 1 post-exposure; a similar decrease of lymphocytes was also observed in the LDLN. The results indicate that cells in the airways and in the LDLN of individuals with established airway inflammation undergo cell death when exposed to hematite NPs. A possible explanation for this toxic response is the extensive generation of reactive oxygen species (ROS) in the pro-oxidative environment of inflamed airways. This study demonstrates how sensitized and non-sensitized mice respond differently to hematite NP exposure, and it highlights the importance of including individuals with respiratory disorders when evaluating health effects of inhaled nanomaterials. [ABSTRACT FROM AUTHOR]

There is a compelling need to understand and assess the toxicity of industrially produced nanoparticles (NPs). In order to appreciate the long-term effects of NPs, sensitive human-based screening tests that comprehensively map the NP properties are needed to detect possible toxic mechanisms. Animal models can only be used in a limited number of test applications and are subject to ethical concerns, and the interpretation of experiments in animals is also distorted by the species differences. Here, we present a novel easy-to-perform highly sensitive whole-blood model using fresh non-anticoagulated human blood, which most justly reflects complex biological cross talks in a human system. As a demonstrator of the tests versatility, we evaluated the toxicity of TiO 2 NPs that are widely used in various applications and otherwise considered to have relatively low toxic properties. We show that TiO 2 NPs at very low concentrations (50 ng/mL) induce strong activation of the contact system, which in this model elicits thromboinflammation. These data are in line with the finding of components of the contact system in the protein corona of the TiO 2 NPs after exposure to blood. The contact system activation may lead to both thrombotic reactions and generation of bradykinin, thereby representing fuel for chronic inflammation in vivo and potentially long-term risk of autoimmunity, arteriosclerosis and cancer. These results support the notion that this novel whole-blood model represents an important contribution to testing of NP toxicity. [ABSTRACT FROM AUTHOR]

Bacterial biofilms cause a range of problems in many areas and especially in health care. Biofilms are difficult to eradicate with traditional antibiotics and consequently there is a need for alternative ways to prevent and/or remove bacterial biofilms. Furthermore, the emergence of antibiotic resistance in bacteria creates a challenge to find new types of antibiotics with a lower evolutionary pressure for resistance development. One route to develop such drugs is to target the so called virulence factors, i.e. bacterial systems used when bacteria infect a host cell. This study investigates synergy effects between Ga(III) ions, previously reported to suppress biofilm formation and growth in bacteria, and salicylidene acylhydrazides (hydrazones) that have been proposed as antivirulence drugs targeting the type three secretion system used by several Gram-negative pathogens, including Pseudomonas aerugionosa, during bacterial infection of host cells. A library of hydrazones was screened for: Fe(III) binding, enhanced anti-biofilm effect with Ga(III) on P. aeruginosa, and low cytotoxicity to mammalian cells. The metal coordination for the most promising ligand, 2-Oxo-2-[N-(2,4,6-trihydroxy-benzylidene)-hydrazino]-acetamide (ME0163) with Ga(III) was investigated using extended X-ray absorption fine structure spectroscopy as well as density functional theory. The results showed that Ga(III) chelates the hydrazone with 5- and 6-membered chelating rings, and that the Ga(III)-ME0163 complex enhanced the antibiofilm effect of Ga(III) while suppressing the type three secretion system in P. aeruginosa. The latter effect was not observed for the hydrazone alone and was similar for Ga(III)-citrate and Ga(III)-ME0163 complexes, indicating that the inhibition of virulence was caused by Ga(III). [ABSTRACT FROM AUTHOR]

Background: Exposure to particulate matter (PM) air pollution especially derived from traffic is associated with increases in cardiorespiratory morbidity and mortality. In this study, we evaluated the ability of novel vehicle cabin air inlet filters to reduce diesel exhaust (DE)-induced symptoms and markers of inflammation in human subjects. Methods: Thirty healthy subjects participated in a randomized double-blind controlled crossover study where they were exposed to filtered air, unfiltered DE and DE filtered through two selected particle filters, one with and one without active charcoal. Exposures lasted for one hour. Symptoms were assessed before and during exposures and lung function was measured before and after each exposure, with inflammation assessed in peripheral blood five hours after exposures. In parallel, PM were collected from unfiltered and filtered DE and assessed for their capacity to drive damaging oxidation reactions in a cell-free model, or promote inflammation in A549 cells. Results: The standard particle filter employed in this study reduced PM10 mass concentrations within the exposure chamber by 46%, further reduced to 74% by the inclusion of an active charcoal component. In addition use of the active charcoal filter was associated by a 75% and 50% reduction in NO2 and hydrocarbon concentrations, respectively. As expected, subjects reported more subjective symptoms after exposure to unfiltered DE compared to filtered air, which was significantly reduced by the filter with an active charcoal component. There were no significant changes in lung function after exposures. Similarly diesel exhaust did not elicit significant increases in any of the inflammatory markers examined in the peripheral blood samples 5 hour post-exposure. Whilst the filters reduced chamber particle concentrations, the oxidative activity of the particles themselves, did not change following filtration with either filter. In contrast, diesel exhaust PM passed through the active charcoal combination filter appeared less inflammatory to A549 cells. Conclusions: A cabin air inlet particle filter including an active charcoal component was highly effective in reducing both DE particulate and gaseous components, with reduced exhaust-induced symptoms in healthy volunteers. These data demonstrate the effectiveness of cabin filters to protect subjects travelling in vehicles from diesel exhaust emissions. [ABSTRACT FROM AUTHOR]

Abstract: Chlorine (Cl2) is an industrial gas that is highly toxic and irritating when inhaled causing tissue damage and an acute inflammatory response in the airways followed by a long-term airway dysfunction. The aim of this study was to evaluate whether early anti-inflammatory treatment can protect against the delayed symptoms in Cl2-exposed mice. BALB/c mice were exposed by nose-only inhalation using 200ppm Cl2 during 15min. Assessment of airway hyperresponsiveness (AHR), inflammatory cell counts in bronchoalveolar lavage, occurrence of lung edema and lung fibrosis were analyzed 24h or 14days post-exposure. A single dose of the corticosteroid dexamethasone (10 or 100mg/kg) was administered intraperitoneally 1, 3, 6, or 12h following Cl2 exposure. High-dose of dexamethasone reduced the acute inflammation if administered within 6h after exposure but treated animals still displayed a significant lung injury. The effect of dexamethasone administered within 1h was dose-dependent; high-dose significantly reduced acute airway inflammation (100mg/kg) but not treatment with the relatively low-dose (10mg/kg). Both doses reduced AHR 14days later, while lung fibrosis measured as collagen deposition was not significantly reduced. The results point out that the acute inflammation in the lungs due to Cl2 exposure only partly is associated with the long-term AHR. We hypothesize that additional pathogenic mechanisms apart from the inflammatory reactions contribute to the development of long-term airway dysfunction. By using this mouse model, we have validated early administration of corticosteroids in terms of efficacy to prevent acute lung injury and delayed symptoms induced by Cl2 exposure. [Copyright &y& Elsevier]

Abstract: In this study aerosol samples collected in an Asian mega-city (Kabul, Afghanistan) were compared to PM samples collected in a European location with traffic (Umeå, Sweden) and a reference urban dust material (SRM 1649b). The toxicity of each sample towards normal human bronchial epithelial (NHBE) cells and a human bronchial epithelial cell line (BEAS-2B) was tested along with their ability to induce reactive oxygen species (ROS) formation and inflammatory responses. The extracts’ morphology and elemental composition was studied by SEM-EDXRF, and filter samples were analyzed for metals and organic compounds. The PM from Kabul contained a larger fraction of fine particles, 19 times more polyaromatic hydrocarbons (PAH) and 37 times more oxygenated PAH (oxy-PAH) compared to samples from Umeå. The PM-samples from Kabul and the reference material (SRM 1649b) induced significantly stronger oxidative stress responses than the samples from Umeå. Furthermore, samples collected in Kabul induced significantly higher secretion of the cytokines IL-6, IL-8 and GM-CSF while SRM1649b induced a cytokine pattern more similar to samples collected in Umeå. Several properties of the particles could potentially explain these differences, including differences in their size distribution and contents of PAH and oxy-PAH, possibly in combination with their relative transition metal contents. [Copyright &y& Elsevier]

Context: Titanium dioxide (TiO2) nanoparticles (NPs) are regarded as relatively non-toxic in concentrations occurring in occupational environments. Nevertheless, it is conceivable that adverse health effects may develop in sensitive populations such as individuals with respiratory diseases. Objective: We investigated whether single or repeated exposure to TiO2 could aggravate inflammatory responses in naïve mice and mice with ovalbumin (OVA)-induced airway inflammation. Methods: Exposure to aerosolized TiO2 was performed during OVA sensitization, before, or during the OVA challenge period. The effects on respiratory physiology, inflammatory cells in bronchoalveolar lavage (BAL) and inflammatory mediators in BAL and serum were assessed 24 h after the last OVA challenge or TiO2 exposure. Results: A single exposure of TiO2 had a marked effect on responses in peripheral airways and increasing infiltration of neutrophils in airways of naïve animals. Marked aggravation of airway responses was also observed in animals with allergic disease provided that the single dose TiO2 was given before allergen challenge. Repeated exposures to TiO2 during sensitization diminished the OVA-induced airway eosinophilia and airway hyperresponsiveness but concomitant exposure to TiO2 during the OVA challenge period resulted in neutrophilic airway inflammation and a decline in general health condition as indicated by the loss of body weight. Conclusion: We conclude that inhalation of TiO2 may aggravate respiratory diseases and that the adverse health effects are highly dependent on dose and timing of exposure. Our data imply that inhalation of NPs may increase the risk for individuals with allergic airway disease to develop symptoms of severe asthma. [ABSTRACT FROM AUTHOR]

Abstract: Context: Exposure to toxic alkylating mustard agents causes both acute and long-term effects to the lungs as indicated by increased number of inflammatory cells in airways, lung edema and lung tissue fibrosis. We have previously demonstrated that treatment with the corticosteroid dexamethasone 1h after lung exposure to the nitrogen mustard analog melphalan protects mice from acute and sub-acute inflammatory responses, as well as from lung tissue fibrosis. Objective: In order to address the importance of early anti-inflammatory treatment, we investigated the therapeutic effect of dexamethasone administered 1, 2 or 6h following exposure to melphalan. Methods: C57BL/6 mice were exposed to melphalan and treated with dexamethasone 1, 2 or 6h after exposure. Twenty hours or 14 days post exposure mice were subjected to analysis of respiratory mechanics where the effects of incremental doses of methacholine on central and peripheral lung components were measured. We also determined the amount of inflammatory cells in the bronchoalveolar lavage fluid and measured the amount of collagen content in the lungs. Results: Melphalan exposure increased airway hyperresponsiveness in both central and peripheral airways and induced an airway inflammation dominated by infiltration of macrophages and neutrophils. Dexamethasone given 1h after exposure to melphalan provided better protection against airway inflammation than administration 2 or 6h after exposure. Collagen deposition 14 days after exposure was decreased due to dexamethasone treatment. Conclusion: Early treatment with dexamethasone is important in order to reduce the airway hyperresponsiveness and inflammation caused by toxic alkylating mustards such as melphalan. [Copyright &y& Elsevier]

We have compared the cellular uptake and responses of five preparations of nanocrystalline titanium dioxide (TiO2) between normal human bronchial epithelial (NHBE) cells and epithelial cell lines (A549 and BEAS-2B). The P25 nanoparticles, containing both anatase and rutile modifications, induced reactive oxygen species (ROS) and secretion of the neutrophil chemoattractant IL-8 in all three cell types used. Pure anatase and rutile particles provoked differential IL-8 response in A549 and no response in BEAS-2B cells despite similar formation of ROS. The pure TiO2 modifications also provoked release of the inflammatory mediators: IL-6, G-CSF and VEGF, in NHBE cells but not in the two cell lines. We conclude that the responsiveness of lung epithelial cells is strongly dependent on both the physicochemical properties of TiO2 nanoparticles and the type of responder cells. The differential pro-inflammatory responsiveness of primary lung epithelial cells compared with immortalized cell lines should be considered in the assessment of adverse reactions to inhaled nanoparticles. [ABSTRACT FROM AUTHOR]

Background: Regulatory T cells have been implicated in the pathogenesis of COPD by the increased expression of CD25 on helper T cells along with enhanced intracellular expression of FoxP3 and low/absent CD127 expression on the cell surface.Method: Regulatory T cells were investigated in BALF from nine COPD subjects and compared to fourteen smokers with normal lung function and nine never-smokers.Results: In smokers with normal lung function, the expression of CD25+CD4+ was increased, whereas the proportions of FoxP3+ and CD127+ were unchanged compared to never-smokers. Among CD4+ cells expressing high levels of CD25, the proportion of FoxP3+ cells was decreased and the percentage of CD127+ was increased in smokers with normal lung function. CD4+CD25+ cells with low/absent CD127 expression were increased in smokers with normal lung function, but not in COPD, when compared to never smokers.Conclusion: The reduction of FoxP3 expression in BALF from smokers with normal lung function indicates that the increase in CD25 expression is not associated with the expansion of regulatory T cells. Instead, the high CD127 and low FoxP3 expressions implicate a predominantly non-regulatory CD25+ helper T-cell population in smokers and stable COPD. Therefore, we suggest a smoking-induced expansion of predominantly activated airway helper T cells that seem to persist after COPD development. [ABSTRACT FROM AUTHOR]

Background: Exposure to seasonal or indoor allergens may cause sensitisation and development of allergic airway diseases. We have previously demonstrated that the non-proteolytic major house dust mite (HDM) allergen Der p 2 stimulates pro-inflammatory responses in bronchial epithelial cells. We aimed to determine if other clinically relevant non-proteolytic aeroallergens originating from HDMs, storage mites, cat, dog, birch and timothy also activate respiratory epithelial cells. Methods: Cultures of human bronchial epithelial cell line BEAS-2B, normal human bronchial epithelial cells and alveolar epithelial cell line A549 were exposed to recombinant (r)Der p 2, natural (n)Der f 2, rEur m 2, rLep d 2, rFel d 1, nFel d 1, rCan f 2, rBet v 1 or rPhl p 5a. A panel of secreted mediators and expression of cell adhesion receptors involved in recruitment, survival and adhesion of inflammatory cells in asthmatic airways was assessed. Results: The mite allergens rDer p 2, nDer f 2, rEur m 2 and rLep d 2 as well as the cat and dog allergens rFel d 1, nFel d 1 and rCan f 2 induced granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interleukin (IL)-6, IL-8, monocyte-chemotactic protein-1 and macrophage inflammatory protein-3α secretion from bronchial epithelial cells as well as surface expression of intracellular adhesion molecule-1. The pollen allergens rBet v 1 and rPhl p 5a from birch and timothy did not activate the cells. None of the studied allergens affected the alveolar epithelial cells. Conclusion: These results show that both mite and structurally unrelated cat and dog allergens can activate respiratory epithelial cells by adjuvant-like protease-independent mechanisms. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Nanomaterial of titanium dioxide (TiO2) is manufactured in large-scale production plants, resulting in risks for accidental high exposures of humans. Inhalation of metal oxide nanoparticles in high doses may lead to both acute and long-standing adverse effects. By using the Dark Agouti (DA) rat, a strain disposed to develop chronic inflammation following exposure to immunoactivating adjuvants, we investigated local and systemic inflammatory responses after lung exposure of nanosized TiO2 particles up to 90 days after intratracheal instillation. TiO2 induced a transient response of proinflammatory and T-cell-activating cytokines (interleukin [IL]-1αα, IL-1ββ, IL-6, cytokine-induced neutrophil chemoattractant [CINC]-1, granulocyte--macrophage colony-stimulating factor [GM-CSF], and IL-2) in airways 1--2 days after exposure, accompanied by an influx of eosinophils and neutrophils. Neutrophil numbers remained elevated for 30 days, whereas the eosinophils declined to baseline levels at Day 8, simultaneously with an increase of dendritic cells and natural killer (NK) cells. The innate immune activation was followed by a lymphocyte expansion that persisted throughout the 90-day study. Lymphocytes recruited to the lungs were predominantly CD4++ helper T-cells, but we also demonstrated presence of CD8++ T-cells, B-cells, and CD25++ T-cells. In serum, we detected both an early cytokine expression at Days 1--2 (IL-2, IL-4, IL-6, CINC-1, IL-10, and interferon-gamma [IFN-γγ] and a second response at Day 16 of tumor necrosis factor-alpha (TNF-αα), indicating systemic late-phase effects in addition to the local response in airways. In summary, these data demonstrate a dynamic response to TiO2 nanoparticles in the lungs of DA rats, beginning with an innate immune activation of eosinophils, neutrophils, dendritic cells, and NK cells, followed by a long-lasting activation of lymphocytes involved in adaptive immunity. The results have implications for the assessment of risks for adverse and persistent immune stimulation following nanoparticle exposures in sensitive populations. [ABSTRACT FROM AUTHOR]

Background: A suggested role for T cells in COPD pathogenesis is based on associations between increased lung cytotoxic T lymphocyte (CD8+) numbers and airflow limitation. CD69 is an early T cell activation marker. Natural Killer cell group 2 D (NKG2D) receptors are co-stimulatory molecules induced on CD8+ T cells upon activation. The activating function of NKG2 D is triggered by binding to MHC class 1 chain-related (MIC) molecules A and B, expressed on surface of stressed epithelial cells. The aim of this study was to evaluate the expression of MIC A and B in the bronchial epithelium and NKG2 D and CD69 on BAL lymphocytes in subjects with COPD, compared to smokers with normal lung function and healthy never-smokers.Methods: Bronchoscopy with airway lavages and endobronchial mucosal biopsy sampling was performed in 35 patients with COPD, 21 healthy never-smokers and 16 smokers with normal lung function. Biopsies were immunohistochemically stained and BAL lymphocyte subsets were determined using flow cytometry.Results: Epithelial CD3+ lymphocytes in bronchial biopsies were increased in both smokers with normal lung function and in COPD patients, compared to never-smokers. Epithelial CD8+ lymphocyte numbers were higher in the COPD group compared to never-smoking controls. Among gated CD3+cells in BAL, the percentage of CD8+ NKG2D+ cells was enhanced in patients with COPD and smokers with normal lung function, compared to never-smokers. The percentage of CD8+ CD69+ cells and cell surface expression of CD69 were enhanced in patients with COPD and smokers with normal lung function, compared to never-smokers. No changes in the expression of MIC A or MIC B in the airway epithelium could be detected between the groups, whereas significantly decreased soluble MICB was detected in bronchial wash from smokers with normal lung function, compared to never-smokers.Conclusions: In COPD, we found increased numbers of cytotoxic T cells in both bronchial epithelium and airway lumen. Further, the proportions of CD69- and NKG2D-expressing cytotoxic T cells in BAL fluid were enhanced in both subjects with COPD and smokers with normal lung function and increased expression of CD69 was found on CD8+ cells, indicating the cigarette smoke exposure-induced expansion of activated cytotoxic T cells, which potentially can respond to stressed epithelial cells. [ABSTRACT FROM AUTHOR]

Background: Volatile monoisocyanates are formed through thermal degradation when products containing polyurethane are heated. Repeated exposure to diisocyanates, such as toluene diisocyanate (TDI) are a well-known cause of occupational asthma. However, although monoisocyanates are abundant in occupational settings, there are few data concerning their ability to provoke immune reactions and asthma. We compared immune reactivity and respiratory disease following single or repeated inhalation exposures to the monoisocyanates methyl isocyanate (MIC) and isocyanic acid (ICA) with the effects of TDI. Methods:Isocyanates were administrated either as single vapor exposures or as repeated intranasal instillations in rats. Adverse health effects were monitored by analyzing airway inflammation, respiratory function and weight gain. Immune reactivity caused by repeated exposures was studied by analysis of isocyanate-specific antibodies and airway infiltration of immune competent cells. Results: Repeated exposures to TDI induced airway infiltration of neutrophils and lymphocytes, while neither MIC nor ICA provoked a detectable inflammatory response. Antibodies against isocyanate-albumin conjugates were detected in serum after both exposures to TDI and MIC, but not to ICA. TDI-exposed rats also displayed IgG antibodies against MIC-albumin conjugates. Even though MIC did not induce airway inflammation, single exposure provoked an increase in airway resistance and repeated exposures caused weight loss similar to that of TDI. Conclusions: Airway exposure to TDI produces an antibody response not only against TDI but also against MIC-protein conjugates. This indicates that immune reactivity against abundant monoisocyanates in occupational environments can occur in individuals pre-sensitized with low abundance but highly sensitizing diisocyanates. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The pathogenesis of lung injury by exposure to highly toxic sulfur and nitrogen mustards involves alkylating damage of the respiratory epithelium followed by an acute inflammatory response and lung edema. The acute phase is followed by long-term respiratory complications characterized by bronchitis, lung fibrosis, and airway hyperreactivity. In this study, we utilized a mouse model for airway inflammation induced by inhalation exposure to the alkylating nitrogen mustard melphalan, in order to investigate possible beneficial treatment effects by the corticosteroid dexamethasone. In addition, we investigated therapeutic efficacy of liposome-encapsuled vitamin E, an antioxidant formulation previously shown to be efficient in counteracting inflammatory conditions. Influx of inflammatory cells to airways, edema formation, and expression of different cytokines were analyzed 6 and 18 hours after exposure to melphalan. In order to evaluate long-term lung effects, we also investigated collagen deposition and accumulation of lymphocytes at 2 and 4 weeks after exposure. A single intraperitoneal injection of dexamethasone (10 mg/kg body weight) 1 hour after melphalan exposure significantly reduced interleukin (IL)-1 and IL-6 in bronchoalveolar lavage fluid (BALF) and diminished the acute airway inflammation. Our results also indicate that early single-dose treatment with dexamethasone protects against long-term effects observed 2–4 weeks after melphalan exposure, as indicated by reduced lymphocytic response in airways and decreased collagen deposition. Furthermore, our results indicate that also vitamin E (50 mg/kg) reduces acute inflammatory cell influx, and suppresses collagen formation in lung tissue, indicating that this drug could be used in combination with corticosteroids for protection against chemical-induced lung injury. [ABSTRACT FROM AUTHOR]

The mechanisms behind airway inflammation in chronic obstructive pulmonary disease (COPD) are still not well understood. Here we investigated lymphocyte subtypes in bronchoalveolar lavage fluid, likely to be involved in the pathogenesis of COPD, as well as exploring the effect of smoking cessation. Differential cell counts and T cell subsets were determined in BAL fluid from nineteen individuals with stable COPD (seven smokers, twelve ex-smokers) compared to twelve age-matched never-smokers and thirteen smoking-matched smokers with normal lung function. COPD-patients had higher percentages of airway CD8+ T cells compared to never-smokers. An increased population of CD4+ T cells expressed high levels of CD25 in smokers and COPD patients compared to never-smokers, suggesting the presence of regulatory T cells. As the T cell populations in smokers with normal lung function and COPD-patients were similar, the impact of current smoking in COPD was addressed in a subgroup analysis. Activation of CD8+ T cells was found regardless of smoking habits. In contrast, the enhanced expression of γ /δ T cells, was mainly associated with current smoking, whilst the increase in T regulatory cells appeared related to both smoking and COPD. Regardless of smoking habits, CD8+ T cell activation was found in COPD, supporting the contention that this T cell subset may play a role in the pathogenesis of COPD. As CD8+ T cells coexist with immunoregulatory CD4+ T cells in airways of COPD patients, it is likely that both cytotoxic T-cell responses and immunosuppressive mechanisms may be of importance in COPD pathogenesis. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the antibacterial and cytotoxic effect of surfaces with sulphonate brushes containing silver salts. By using the same type of samples for both cytotoxicity and antibacterial studies, these two parameters could be compared in a controlled way. The silver was incorporated into the brush in four different forms to enable release of silver ions at different concentrations and different rates. It was found that although the surfaces displayed very good antibacterial properties in buffer solutions, this effect disappeared in systems with high protein content. Similarly, the silver-containing surfaces displayed cytotoxic effects in the absence of serum proteins but this effect was reduced in the presence of serum. The speciation of silver in the different solutions is discussed. Cytotoxic and antibacterial effects are compared at the different silver concentrations released. The implications of a concentration range where silver could be used to kill bacterial without harmful effects on mammalian cells are also discussed and questioned. [Copyright &y& Elsevier]

Inhaled environmental antigens, i.e. allergens, cause allergic symptoms in millions of patients worldwide. As little is known about the fate of an allergen upon inhalation, we addressed this issue for a major dust mite allergen, Der p 2. First, a model for Der p 2-sensitization was established in C57BL/6 J mice, in which sensitized mice mounted a Der p 2-specific IgE-response with eosinophilic lung inflammation after allergen challenge in the airways. In this model, we applied recombinant Der p 2 carrying a novel C-terminal tetrapeptide Sel-tag enabling labelling with the gamma-emitting radionuclide 75Se at a single selenocysteine residue ([75Se]Der p 2). In vivo tracking of intratracheally administered [75Se]Der p 2 using whole-body autoradiography revealed that [75Se]Der p 2-derived radioactivity persisted in the lungs of sensitized mice as long as 48 h. Radioactivity was also detected in kidneys, liver and in enlarged lung-associated lymph nodes. Interestingly, a larger proportion of radioactivity was found in the lungs of sensitized compared with nonsensitized mice 24 h after intratracheal instillation of [75Se]Der p 2. A radioactive protein corresponding to intact Der p 2 could only be detected in the lungs, whereas [75Se]Der p 2-derived radioactivity was recovered in known selenoproteins both in lung and other organs. Hence, using the recently developed Sel-tag method in a mouse model for Der p 2-sensitization, we could track the fate of an inhaled allergen in vivo. Based upon our findings, we conclude that the inflammatory state of the lung influences the rate of metabolism and clearance of Der p 2. Thus, an allergic response to the inhaled allergen may lead to prolonged retention of Der p 2 in the lung. [ABSTRACT FROM AUTHOR]

Unintentional exposure to potent synthetic opioids during law enforcement seizures and rescue operations can potentially result in incapacitating effects or life-threatening respiratory depression. The hazard comes mainly from inhalation exposure, however, the skin contact risk should be considered. In the present study, the skin penetration of fentanyl and the efficacy of different decontamination protocols were evaluated by applying two forms of fentanyl on dermatomed human skin mounted in a diffusion cell. Studies were performed on dry skin or skin moistened by water, sweat or hand sanitizer. The free base of fentanyl displayed greater skin penetration ability than the hydrochloride salt and a higher steady state penetration rate of fentanyl in solution compared to powder on dry skin. Sweaty skin increased the penetration rate, both when applied in solution and as powder. The hand sanitizer increased skin penetration of the free base fentanyl but not the hydrochloride salt. Of the evaluated decontamination procedures, only soapy water demonstrated a general efficacy. In conclusion, the skin contact hazard of fentanyl is highly dependent on the exposure conditions and contamination density. The risk for physiological effects of fentanyl is assessed to occur only at very high exposures on sweaty skin. In such events, skin decontamination using soap and water is estimated to be a sufficient decontamination procedure. • Free base fentanyl displayed higher skin penetration rate compared to the hydrochloride salt. • Fentanyl skin penetration was increased when exposed on sweaty skin. • Hand sanitizer increased the skin penetration of the free base fentanyl. • Decontamination using soapy water demonstrated generic efficacy for removal of fentanyl from skin. [ABSTRACT FROM AUTHOR]

Diseases in the respiratory tract rank among the leading causes of death in the world, and thus novel and optimized treatments are needed. The lungs offer a large surface for drug absorption, and the inhalation of aerosolized drugs are a well-established therapeutic modality for local treatment of lung conditions. Nanoparticle-based drug delivery platforms are gaining importance for use through the pulmonary route. By using porous carrier matrices, higher doses of especially poorly soluble drugs can be administered locally, reducing their side effects and improving their biodistribution. In this study, the feasibility of mesoporous silica particles (MSPs) as carriers for anti-inflammatory drugs in the treatment of airway inflammation was investigated. Two different sizes of particles on the micron and nanoscale (1 µm and 200 nm) were produced, and were loaded with dexamethasone (DEX) to a loading degree of 1:1 DEX:MSP. These particles were further surface-functionalized with a polyethylene glycol–polyethylene imine (PEG–PEI) copolymer for optimal aqueous dispersibility. The drug-loaded particles were administered as an aerosol, through inhalation to two different mice models of neutrophil-induced (by melphalan or lipopolysaccharide) airway inflammation. The mice received treatment with either DEX-loaded MSPs or, as controls, empty MSPs or DEX only; and were evaluated for treatment effects 24 h after exposure. The results show that the MEL-induced airway inflammation could be treated by the DEX-loaded MSPs to the same extent as free DEX. Interestingly, in the case of LPS-induced inflammation, even the empty MSPs significantly down-modulated the inflammatory response. This study highlights the potential of MSPs as drug carriers for the treatment of diseases in the airways. [ABSTRACT FROM AUTHOR]

Background: Cytotoxic lymphocytes are increased in the airways of COPD patients. Whether this increase is driven primarily by the disease or by smoking is not clear, nor whether it correlates with the rate of decline in lung function.Methods: Bronchoscopy with BAL was performed in 52 subjects recruited from the longitudinal OLIN COPD study according to pre-determined criteria; 12 with COPD and a rapid decline in lung function (loss of FEV1 ≥ 60 ml/year), 10 with COPD and a non-rapid decline in lung function (loss of FEV1 ≤ 30 ml/year), 15 current and ex-smokers and 15 non-smokers with normal lung function. BAL lymphocyte subsets were determined using flow cytometry.Results: In BAL fluid, the proportions of NK, iNKT and NKT-like cells all increased with pack-years. Within the COPD group, NK cells - but not iNKT or NKT-like cells - were significantly elevated also in subjects that had quit smoking. In contrast, current smoking was associated with a marked increase in iNKT and NKT-like cells but not in NK cells. Rate of lung function decline did not significantly affect any of the results.Conclusions: In summary, increased proportions of NK cells in BAL fluid were associated with COPD; iNKT and NKT-like cells with current smoking but not with COPD. Interestingly, NK cell percentages did not normalize in COPD subjects that had quit smoking, indicating that these cells might play a role in the continued disease progression seen in COPD even after smoking cessation.Trial Registration: Clinicaltrials.gov identifier NCT02729220 . [ABSTRACT FROM AUTHOR]

Background: Exposure to particulate matter (PM) air pollution especially derived from traffic is associated with increases in cardiorespiratory morbidity and mortality. In this study, we evaluated the ability of novel vehicle cabin air inlet filters to reduce diesel exhaust (DE)-induced symptoms and markers of inflammation in human subjects.Methods: Thirty healthy subjects participated in a randomized double-blind controlled crossover study where they were exposed to filtered air, unfiltered DE and DE filtered through two selected particle filters, one with and one without active charcoal. Exposures lasted for one hour. Symptoms were assessed before and during exposures and lung function was measured before and after each exposure, with inflammation assessed in peripheral blood five hours after exposures. In parallel, PM were collected from unfiltered and filtered DE and assessed for their capacity to drive damaging oxidation reactions in a cell-free model, or promote inflammation in A549 cells.Results: The standard particle filter employed in this study reduced PM10 mass concentrations within the exposure chamber by 46%, further reduced to 74% by the inclusion of an active charcoal component. In addition use of the active charcoal filter was associated by a 75% and 50% reduction in NO2 and hydrocarbon concentrations, respectively. As expected, subjects reported more subjective symptoms after exposure to unfiltered DE compared to filtered air, which was significantly reduced by the filter with an active charcoal component. There were no significant changes in lung function after exposures. Similarly diesel exhaust did not elicit significant increases in any of the inflammatory markers examined in the peripheral blood samples 5 hour post-exposure. Whilst the filters reduced chamber particle concentrations, the oxidative activity of the particles themselves, did not change following filtration with either filter. In contrast, diesel exhaust PM passed through the active charcoal combination filter appeared less inflammatory to A549 cells.Conclusions: A cabin air inlet particle filter including an active charcoal component was highly effective in reducing both DE particulate and gaseous components, with reduced exhaust-induced symptoms in healthy volunteers. These data demonstrate the effectiveness of cabin filters to protect subjects travelling in vehicles from diesel exhaust emissions. [ABSTRACT FROM AUTHOR]

Summary Allergic airway inflammation induced in mice is T-cell dependent and recruitment of eosinophils to airspaces requires both αβ and γδ T cells. From previous studies it is evident that αβ T cells are essential for the allergic T helper type 2 (Th2)-like response, while the mechanistic contribution of γδ T cells is still unclear. In this study, we have investigated the role of γδ T cells in allergic airway eosinophilia induced by ovalbumin hypersensitivity. By comparing the responsiveness to sensitizing allergen of wild-type mice with that of T-cell receptor γδ knockout mice (TCRγδ KO) we demonstrated that mice lacking γδ T cells are defective in the systemic ovalbumin-specific immunoglobulin E (IgE) response. Furthermore, after aerosol challenge with allergen, γδ T-cell deficient mice exhibited a significantly decreased migration of B cells and natural killer cells to airways and reduced levels of allergen-specific IgG and IgA in bronchoalveolar lavage fluid. The role for B cells in the airway inflammation was indicated by the impaired ability of mice lacking functional B cells to evoke an eosinophilic response. The diminished eosinophilia in TCRγδ KO mice could not be explained by a defective Th2 activation since these mice displayed a normal IgG response in serum and an unaffected IG2b /IgG1 ratio in airways. Analysis of immunoregulatory cytokines in isolated lung tissue, thoracic lymph nodes and spleen further supported the notion that these mice are able to evoke a sufficient activation of T helper cells and that γδ T cells are not required for maintaining the Th2 profile. These results indicate that γδ T cells contribute to allergic airway inflammation by pathways separate from classical Th2 immune activation. [ABSTRACT FROM AUTHOR]