Combination of urea-crosslinked hyaluronic acid and sodium ascorbyl phosphate for the treatment of inflammatory lung diseases: An in vitro study

This in vitro study evaluated, for the first time, the safety and the biological activity of a novel urea-crosslinked hyaluronic acid component and sodium ascorbyl phosphate (HA-CL - SAP), singularly and/or in combination, intended for the treatment of inflammatory lung diseases. The aim was to understand if the combination HA-CL - SAP had an enhanced activity with respect to the combination native hyaluronic acid (HA) - SAP and the single SAP, HA and HA-CL components. Sample solutions displayed pH, osmolality and viscosity values suitable for lung delivery and showed to be not toxic on epithelial Calu-3 cells at the concentrations used in this study. The HA-CL - SAP displayed the most significant reduction in interleukin-6 (IL-6) and reactive oxygen species (ROS) levels, due to the combined action of HA-CL and SAP. Moreover, this combination showed improved cellular healing (wound closure) with respect to HA - SAP, SAP and HA, although at a lower rate than HA-CL alone. These preliminary results showed that the combination HA-CL - SAP could be suitable to reduce inflammation and oxidative stress in lung disorders like acute respiratory distress syndrome, asthma, emphysema and chronic obstructive pulmonary disease, where inflammation is prominent.

The Microenvironment of Lung Cancer and Therapeutic Implications

The tumor microenvironment (TME) represents a milieu that enables tumor cells to acquire the hallmarks of cancer. The TME is heterogeneous in composition and consists of cellular components, growth factors, proteases, and extracellular matrix. Concerted interactions between genetically altered tumor cells and genetically stable intratumoral stromal cells result in an "activated/reprogramed" stroma that promotes carcinogenesis by contributing to inflammation, immune suppression, therapeutic resistance, and generating premetastatic niches that support the initiation and establishment of distant metastasis. The lungs present a unique milieu in which tumors progress in collusion with the TME, as evidenced by regions of aberrant angiogenesis, acidosis and hypoxia. Inflammation plays an important role in the pathogenesis of lung cancer, and pulmonary disorders in lung cancer patients such as chronic obstructive pulmonary disease (COPD) and emphysema, constitute comorbid conditions and are independent risk factors for lung cancer. The TME also contributes to immune suppression, induces epithelial-to-mesenchymal transition (EMT) and diminishes efficacy of chemotherapies. Thus, the TME has begun to emerge as the "Achilles heel" of the disease, and constitutes an attractive target for anti-cancer therapy. Drugs targeting the components of the TME are making their way into clinical trials. Here, we will focus on recent advances and emerging concepts regarding the intriguing role of the TME in lung cancer progression, and discuss future directions in the context of novel diagnostic and therapeutic opportunities.

Glucagon-like peptide-1 (GLP-1) reduces mortality and improves lung function in a model of experimental obstructive lung disease in female mice

The incretin hormone glucagon-like peptide-1 (GLP-1) is an important insulin secretagogue and GLP-1 analogs are used for the treatment of type 2 diabetes. GLP-1 displays antiinflammatory and surfactant-releasing effects. Thus, we hypothesize that treatment with GLP-1 analogs will improve pulmonary function in a mouse model of obstructive lung disease. Female mice were sensitized with injected ovalbumin and treated with GLP-1 receptor (GLP-1R) agonists. Exacerbation was induced with inhalations of ovalbumin and lipopolysaccharide. Lung function was evaluated with a measurement of enhanced pause in a whole-body plethysmograph. mRNA levels of GLP-1R, surfactants (SFTPs), and a number of inflammatory markers were measured. GLP-1R was highly expressed in lung tissue. Mice treated with GLP-1R agonists had a noticeably better clinical appearance than the control group. Enhanced pause increased dramatically at day 17 in all control mice, but the increase was significantly less in the groups of GLP-1R agonist-treated mice (P < .001). Survival proportions were significantly increased in GLP-1R agonist-treated mice (P < .01). SFTPB and SFTPA were down-regulated and the expression of inflammatory cytokines were increased in mice with obstructive lung disease, but levels were largely unaffected by GLP-1R agonist treatment. These results show that GLP-1R agonists have potential therapeutic potential in the treatment of obstructive pulmonary diseases, such as chronic obstructive pulmonary disease, by decreasing the severity of acute exacerbations. The mechanism of action does not seem to be the modulation of inflammation and SFTP expression.

Effective inspired oxygen concentration measured via transtracheal and oral gas analysis

BACKGROUND

The fraction of inspired oxygen (F(IO(2))) is quoted for different oxygen delivery systems, but variations in inspiratory flow and tidal volume make precise measurement difficult. We developed a reliable method of measuring the effective F(IO(2)) in patients receiving supplemental oxygen.

METHODS

Ten subjects with chronic hypoxemia breathed through a mouthpiece with a sampling probe connected to a mass spectrometer. Four of the 10 subjects had transtracheal catheters that allowed direct sampling of tracheal gas. We used oxygen concentrations of 47% and 97%, and flow rates between 1 L/min and 8 L/min. We also compared oxygen delivery via nasal cannula and transtracheal catheter. Effective F(IO(2)) was derived from plots of the fractional concentrations of carbon dioxide versus oxygen.

RESULTS

We found excellent correlation between the effective F(IO(2)) values from tracheal and oral sampling (r = 0.960, P < .001). With 97% oxygen via nasal cannula, effective F(IO(2)) increased by 2.5% per liter of increased flow (P < .001); effective F(IO(2)) reached 32.7% at 5 L/min while P(aO(2)) increased by 12 mm Hg per liter of increased flow. In 4 subjects with a transtracheal catheter, effective F(IO(2)) increased 5.0% (P < .001) per liter of increased flow, and P(aO(2)) increased by 13 mm Hg per liter of increased flow, whereas in the same 4 subjects using nasal cannula for oxygen delivery, P(aO(2)) increased by only 6 mm Hg per liter of increased flow.

CONCLUSIONS

Exhaled gas sampled at the mouth accurately reflected the effective F(IO(2)) in the trachea. In relation to inspired oxygen flow, the effective F(IO(2)) was lower than is conventionally thought. Compared to nasal cannula, transtracheal catheter approximately doubled the effective F(IO(2)) at a given flow rate. Accurate knowledge of F(IO(2)) should aid clinicians in managing patients with acute and chronic lung diseases.

Adenosine signaling and the regulation of chronic lung disease

Chronic lung diseases such as asthma, chronic obstructive pulmonary disease and interstitial lung disease are characterized by inflammation and tissue remodeling processes that compromise pulmonary function. Adenosine is produced in the inflamed and damaged lung where it plays numerous roles in the regulation of inflammation and tissue remodeling. Extracellular adenosine serves as an autocrine and paracrine signaling molecule by engaging cell surface adenosine receptors. Preclinical and cellular studies suggest that adenosine plays an anti-inflammatory role in processes associated with acute lung disease, where activation of the A(2A)R and A(2B)R has promising implications for the treatment of these disorders. In contrast, there is growing evidence that adenosine signaling through the A(1)R, A(2B)R and A(3)R may serve pro-inflammatory and tissue remodeling functions in chronic lung diseases. This review discusses the current progress of research efforts and clinical trials aimed at understanding the complexities of these signaling pathway as they pertain to the development of treatment strategies for chronic lung diseases.

Markers of respiratory inflammation in horses in relation to seasonal changes in air quality in a conventional racing stable

Airborne factors in a conventionally managed racing stable and markers of pulmonary inflammation in the stabled horses were investigated on 3 occasions at 6-month intervals, including 2 winter periods and the intervening summer period. The stable measurements included inside and outside ambient temperature and relative humidity, levels of total and respirable dust, endotoxin, and 1,3-beta-glucan. Horses (n = 12) were examined in detail clinically as well as by endoscopy, bronchoalveolar lavage (BAL) cytology, and real-time polymerase chain reaction (RT-PCR) analysis of BAL-cells for IL-6 and IL-10 mRNA. Indoor measurements showed low dust levels irrespective of season. Inhalable dust, as well as 1,3-beta-glucan, were higher during the winter stabling period, whereas endotoxin levels were higher during summer. Complete data from all sampling occasions to be used for further evaluation was obtained for only 8 of the horses. There was a trend for elevation of BAL neutrophils in the horses during winter stabling that coincided with a 3.7-fold increased expression of IL-6 mRNA in BAL cells (P = 0.014). Compared to summer sampling, IL-10 mRNA expression was significantly upregulated in only 1 of the winter sampling occasions, implicating influence on immune regulation by factor/s apart from seasonal differences. Our findings suggest up-regulation of innate immunity in the airways of stabled horses; in particular involving IL-6 in association with mild elevations in respirable dust, 1,3-beta-glucan, and/or cold ambient air. However, given that this study was observational, other unmeasured environmental factors associated with winter stabling need to be considered.

Characterization of endothelin receptors in the peripheral lung tissues of horses unaffected and affected with recurrent airway obstruction

The purpose of the study was to determine and compare the expression of endothelin (ET) receptors in the peripheral lungs of healthy horses and those affected with recurrent airway obstruction (RAO) using reverse transcriptase polymerase chain reaction (RT-PCR), real-time PCR, Western blot analysis, and immunohistochemical techniques. Two groups of horses (7 healthy and 7 RAO-affected) were selected from a pool of horses destined for euthanasia. The grouping of horses was based on the history, clinical scoring, and pulmonary function testing. After euthanasia, gross postmortem evaluation of the lungs was conducted, and lung samples were collected and either stored at -80 degrees C or fixed in zinc-formalin for 12 h. The RT-PCR was performed by using specific primers for ETA and ETB receptors, and beta-actin. To determine the relative gene expression real-time PCR was performed. To detect ET receptor protein expression, Western blotting and immunohistochemical studies were performed using polyclonal antibodies against ETA and ETB receptors and beta-actin. The ET receptor expression was determined by performing either densitometric analyses or scoring of immunostaining. Statistical analyses were performed to detect differences in receptor expression within and between the 2 groups. The results indicated that ET receptor expression, particularly ETB receptors, was significantly greater in the peripheral lungs of RAO-affected horses than in those of healthy horses. Clinical trials using ET receptor antagonists, particularly ETB antagonists might help in developing a therapeutic strategy to treat this career-ending disease.

[Chronic hypoxia state as one of the factors of increased fluorescence of endogenous porphyrins in alive biological tissues]

The hypothesis about the influence of chronic hypoxia in soft alive tissues on the intensity of He-Ne laser-induced fluorescence of endogenous porphyrins in tissues in the red region of the optical spectrum is discussed. Some theoretical prerequisites for enormous accumulation of porphyrins in soft tissues in a number of pathological cases and diseases are presented. A method for conducting clinical experimental trials to verify the hypothesis with the use of up-to-date laser noninvasive fluorescent diagnostics is proposed. Both the theoretical reasoning and new clinical experimental data show that chronic hypoxia can be one of the factors responsible for the appearance of a strong and abnormal laser-induced fluorescent signal from biotissues in the spectrum range 600-800 nm, which is associated with abnormally high accumulation of endogenous porphyrins in tissues.

Relevance of using a human microarray to study gene expression in heaves-affected horses

Environmental causes of heaves are well described, but the molecular mechanisms of the disease remain unclear. Previous studies have highlighted the implications of variations in gene expression, most using reverse transcription polymerase chain reaction (RT-PCR). This well-known technique limits the number of genes that can be studied in a single assay. Microarray appears to be a valuable tool to by-pass this limitation, but so far there has been no equine-specific microarray available on the market. The present study was performed to determine whether a human microarray could be used to study gene expression in nucleated cells originating from peripheral blood and bronchoalveolar lavage fluid (BALF) in heaves-affected horses. With a four-fold cut-off, a total of 46 candidates were identified with differentially regulated genes between heaves-affected horses and controls. A real-time quantitative RT-PCR (RT-QPCR) conducted on a selection of genes, determined on the basis of previous publications, was used to validate the microarray results. The microarray failed to detect the presence of interleukin (IL)-1beta and IL-8 mRNA in the nucleated cells from BALF otherwise confirmed by real-time RT-QPCR. Although some candidate genes have been identified using this method, a complete expression profile of genes related to heaves could not be obtained with the use of the human microarray.

Mucin overproduction in chronic inflammatory lung disease

Mucus overproduction and hypersecretion are commonly observed in chronic inflammatory lung disease. Mucins are gel-forming glycoproteins that can be stimulated by a variety of mediators. The present review addresses the mechanisms involved in the upregulation of secreted mucins. Mucin induction by neutrophil elastase, bacteria, cytokines, growth factors, smoke and cystic fibrosis transmembrane conductance regulator malfunction are also discussed.

Clenbuterol Affects the Expression of Messenger RNA for Interleukin 10 in Peripheral Leukocytes from Horses Challenged Intrabronchially with Lipopolysaccharides

On four occasions, four horses with heaves and four horses with small airway inflammatory diseases inhaled 0.9% saline based aerosol mixtures with or without lipopolysaccharides (LPS). Prior to the first saline and LPS inhalation, horses were untreated, while three and a half days prior to the third and forth inhalation horses had received 0.8 microg/kg clenbuterol intravenously twice daily. The messenger RNA (mRNA) expression of tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-4, IL-6, IL-8, IL-10 and interferon- gamma (IFN- gamma) was investigated by RT-PCR, all of which were expressed in the white blood cells of samples collected. Inhalation of LPS only changed the cytokine expression profile of IL-10, IL-4 and TNF-alpha mRNA which were higher after challenge with LPS. However in those horses that were treated with clenbuterol the LPS-induced IL-10 mRNA expression was shown to be suppressed. Further changes in IL-4 and TNF-alpha were not significant. Thus the results of this study indicated that clenbuterol can modulate the expression of IL-10 mRNA in peripheral white blood cells in those horses with small airway diseases that have been exposed to LPS.

Comparison of the antioxidant status in tracheal and bronchoalveolar epithelial lining fluids in recurrent airway obstruction

REASONS FOR PERFORMING STUDY

Following a period of airway inflammation the clearance of inflammatory cells along the mucociliary escalator may impose a considerable oxidant load on the trachea.

OBJECTIVES

To determine the degree of oxidative stress in tracheal epithelial lining fluid (ELF) in comparison to that present in peripheral airways after an acute exposure to organic dust.

METHODS

Tracheal wash fluid and bronchoalveolar lavage fluid (BALF) were collected for cytology and antioxidant analyses from 6 recurrent airway obstruction (RAO)-affected horses and 6 healthy control horses before and after stabling on straw bedding for 24 h.

RESULTS

In RAO-affected horses, organic dust exposure resulted in a significant decrease in ascorbic acid concentration in tracheal ELF (P<0.0001), which was greater than the decrease in bronchoalveolar ELF (P = 0.0003). The percentage decrease in tracheal ELF ascorbic acid correlated with the percentage decrease in bronchoalveolar ELF ascorbic acid (r = 0.76; P = 0.004) following exposure.

CONCLUSIONS

Acute organic dust exposure results in significant antioxidant depletion in the trachea, which may reflect inflammation and oxidative processes in peripheral airways.

POTENTIAL RELEVANCE

Further work is required to evaluate the role of ascorbic acid depletion in the pathogenesis of RAO.

Transcription factors in airway diseases

Transcription factors regulate the expression of multiple inflammatory genes and play a pivotal role in chronic inflammatory diseases, such as asthma and chronic obstructive pulmonary disease (COPD). Prominent transcription factors in airway diseases include nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1), which together regulate the expression of multiple inflammatory proteins. Glucocorticoids activate glucocorticoid receptors (GR), which act as transcription factors and inhibit transcription induced by NF-kappaB and AP-1. Activation of genes involves hyperacetylation of core histones to open up the chromatin structure to initiate transcription. GR recruit histone deacetylase-2 (HDAC2) to the activated inflammatory gene to switch off transcription. In COPD, there is a marked reduction in HDAC2 expression, resulting in glucocorticoid resistance. Therapeutic implications, which may be generalized to all inflammatory diseases, are discussed.

DNA binding activity of transcription factors in bronchial cells of horses with recurrent airway obstruction

Horses with recurrent airway obstruction (RAO) present many similarities with human asthmatics including airway inflammation, hyperresponsiveness, reversible obstruction, and increased NF-kappaB expression. Studies in experimental asthma models have shown that transcriptions factors such as activator protein-1 (AP-1), GATA-3, cyclic AMP response element binding protein (CREB) and CAAT/enhancer binding protein (C/EBP) may also play an important role in airway inflammation. The purpose of this study was to measure DNA binding activity of these transcription factors in the airways of horses with RAO and to compare it to pulmonary function and bronchoalveolar lavage fluid (BALF) cytology. Seven horses with RAO and six control animals were studied during a moldy hay challenge and after 2 months at pasture. Pulmonary function, BALF cytology and transcription factors' activities in bronchial brushings were measured during hay and pasture exposures. During moldy hay challenge, RAO-affected horses developed severe airway obstruction and inflammation and a significantly higher airway AP-1 binding activity than in controls. After 2 months on pasture, pulmonary function and airway AP-1 binding activity were not different between RAO and control horses. The DNA binding activity of CREB in airways of RAO-affected horses increased significantly after 2 months at pasture and became higher than in controls. A significant positive correlation was detected between AP-1 binding activity and indicators of airway obstruction and inflammation. Airway GATA-3, CEBP and CREB binding activities were negatively correlated with indices of airway obstruction. However, contrarily to CREB binding activity, GATA-3 and CEBP binding activities were not different between RAO and control horses and were unaffected by changes in environment. These data support the view that AP-1 and CREB play a role in modulating airway inflammation in horses with RAO.

Alterations in erythrocyte membrane protein composition in advanced non-small cell lung cancer

Cancer can be associated with hematological complications related to red blood cell (RBC) function, whose physiological roles have now been expanded since it is now known that RBC are also signalling cells. The aim of this study was to explore the alterations occurring in the protein composition of RBC in advanced non-small cell lung cancer (NSCLC). Blood samples from 21 patients with advanced (stages III-IV) NSCLC (16 squamous cell carcinomas and 5 adenocarcinomas), and from 21 healthy volunteers were used. Samples from 6 randomly selected patients and 6 controls were used for the screening of erythrocyte ghost alterations by Differential Scanning Calorimetry (DSC). Samples from 15 patients and 15 controls, different from those used in the DSC measurements, were randomly selected for analysis of the expression of glycophorin (GP) species, band 3, and glycoproteins by SDS-PAGE and Western blotting or lectin enzyme immunoassays. Additionally, 5 patients with chronic obstructive pulmonary disease (COPD) were used as a control group representative of a benign inflammatory disease. Blood samples from the COPD patients were used to analyze the expression of GPs, band 3 and syaloglycoproteins. We observed the following in NSCLC: (a) changes in GP expression levels, mainly decreases in the GPA and GPC monomers, and in the GPAB dimers; (b) a decrease in the band 3 protein level, and (c) alterations in the expression of different sialoglycoproteins. RBC from the COPD patients also showed protein abnormalities, some of them, especially at the level of band 3 and the syaloglycoproteins, being similar to those in NSCLC.

Lack of clinical efficacy of a phosphodiesterase-4 inhibitor for treatment of heaves in horses

Phosphodiesterase-4 (PDE 4) enzyme inhibitors have been shown to have anti-inflammatory properties in various animal disease processes and therefore could be effective drugs for the treatment of equine airway diseases. The purpose of this study was to evaluate the efficacy and adverse effects of the PDE 4 inhibitor L-826,141 in horses with heaves. In a blinded parallel design, horses with heaves exposed daily to moldy hay were given a placebo for 14 days and then administered either L-826,141 (n = 6; loading dose of 1 mg/kg IV followed by 0.5 mg/kg IV q48h) or dexamethasone (n = 6; 0.04 mg/kg IV q24h) from days 15 to 29 (study 1). Pulmonary function and bronchoalveolar (BAL) cytology were evaluated weekly from baseline (day 0) to 29 days. In study 2, horses were treated with L-826,141 (1.0 mg/kg IV q24h) for 8 days. Although ex vivo lipopolysaccharide-induced tumor necrosis factor (TNF)-alpha and LTB4 production by fresh blood were inhibited up to 90% after repeated administrations of L-826,141, this treatment failed to improve lung function. In contrast, dexamethasone (positive control) treatment resulted in significant improvement in lung mechanics and airway function in all horses. Neither drug had a significant effect on BAL total cell counts and differential cytology. Administration of the PDE 4 inhibitor L-826,141 for up to 14 days to horses with heaves was not associated with an improvement in airway function or inflammation. These findings suggest that the PDE 4 enzyme is not a key mediator of lung inflammation in heaves.

Mucus in chronic airway diseases: sorting out the sticky details

Mucous hypersecretion is a major cause of airway obstruction in asthma, chronic obstructive pulmonary disease, and cystic fibrosis. EGFR ligands and IL-13 are known to stimulate mucous induction, but the detailed mechanisms of epithelial mucous regulation have not been well defined. In this issue of the JCI, Tyner et al. show, in a mouse model of chronic mucous hypersecretion, that ciliated epithelial cell apoptosis is inhibited by EGFR activation, allowing IL-13 to stimulate the differentiation of these cells into goblet cells, which secrete mucus. In defining this coordinated, 2-step process, we can consider the therapeutic effects of blocking mucous production. This begs the question, Is it possible to reduce airway obstruction in chronic lung disease by inhibiting EGFR activation and/or by inhibiting IL-13?

Uteroglobin-related protein 1 expression suppresses allergic airway inflammation in mice

RATIONALE

Uteroglobin-related protein (UGRP) 1, which is highly expressed in the epithelial cells of the airways, has been suggested to play a role in lung inflammation.

OBJECTIVES

The aim of study was to understand the effect of overexpressed UGRP1 on lung inflammation in a mouse model of allergic airway inflammation.

METHODS

Ovalbumin-sensitized and -challenged mice, a model for allergic airway inflammation, were used in conjunction with recombinant adenovirus expressing UGRP1.

MEASUREMENTS AND MAIN RESULTS

We demonstrated that intranasal administration of adeno-UGRP1 successfully delivered UGRP1 to the epithelial cells of airways and markedly reduced the number of infiltrating inflammatory cells, particularly eosinophils, in lung tissue as well as the level of proinflammatory cytokines such as interleukin (IL)-4, IL-5, and IL-13 in bronchoalveolar lavage fluids. The healed phase of inflammation was clearly seen in the peripheral areas of adeno-UGRP1-treated mouse lungs.

CONCLUSION

These results demonstrate that UGRP1 can suppress inflammation in the mouse model of allergic airway inflammation. Based on this result, we propose UGRP1 as a novel therapeutic candidate for treating lung inflammation such as is found in asthma.

Immunohistochemical determination of the expression of endothelin receptors in bronchial smooth muscle and epithelium of healthy horses and horses affected by summer pasture-associated obstructive pulmonary disease

OBJECTIVE

To immunohistochemically determine the expression of endothelin (ET) receptors in bronchial smooth muscle and epithelium of healthy horses and horses affected by summer pasture-associated obstructive pulmonary disease (SPAOPD).

SAMPLE POPULATION

Tissue specimens obtained from 8 healthy and 8 SPAOPD-affected horses.

PROCEDURE

Horses were examined and assigned to healthy and SPAOPD groups. Horses were then euthanatized, and tissue specimens containing bronchi of approximately 4 to 8 mm in diameter were immediately collected from all lung lobes, fixed in zinc-formalin solution for 12 hours, and embedded in paraffin. Polyclonal primary antibodies against ET-A or ET-B receptors at a dilution of 1:200 and biotinylated IgG secondary antibodies were applied to tissue sections, followed by the addition of an avidin-biotin immunoperoxidase complex. Photographs of the stained slides were digitally recorded and analyzed by use of image analysis software to determine the intensity of staining. Two-way ANOVA was used for statistical analysis.

RESULTS

The left diaphragmatic lung lobe of SPAOPD-affected horses had a significantly greater area of bronchial smooth muscle that immunostained for ET-A, compared with that for healthy horses. All lung lobes of SPAOPD-affected horses, except for the right diaphragmatic lobe, had significantly greater staining for ET-B receptors in bronchial smooth muscle, compared with results for healthy horses.

CONCLUSIONS AND CLINICAL RELEVANCE

This study revealed overexpression of ET-A and, in particular, ETB receptors in the bronchial smooth muscle of SPAOPD-affected horses, which suggested upregulation of these receptors. These findings improve our understanding of the role of ET-1 in the pathogenesis of SPAOPD.

Effects of N-acetylcysteine on the lung histopathology and oxidant-antioxidant status in rabbits exposed to cigarette smoke

We aimed to evaluate the effects of smoking on the histopathology and the oxidant-antioxidant status of lungs and to test the effects of N-acetylcysteine (NAC) on the induced changes. Rabbits were exposed to cigarette smoke (CS) in a glass chamber for one hour daily for one month. An NAC control group was given intraperitoneal NAC only. CS + NAC rats were exposed to smoke and given intraperitoneal NAC. A control group was exposed to clean air only. At the end of one month, animals were sacrificed and lung tissues were examined histopathologically. Blood levels of protein sulfhydryls, carbonyls, prostaglandin F(2alpha) (PGF(2alpha)) and malondialdehyde (MDA) were measured. Intraparenchymal vascular congestion and thrombosis, intraparenchymal hemorrhage, respiratory epithelial proliferation, number of macrophages in the alveolar and bronchial lumen, alveolar destruction, emphysematous changes and bronchoalveolar hemorrhage scores were significantly increased in rabbits exposed to CS compared with the control group. Protein sulfhydryls were significantly decreased; carbonyls, PGF(2alpha) and MDA levels were significantly increased in the smoke exposed rabbits. Administration of NAC to rabbits exposed to CS caused a reduction in the bronchoalveolar hemorrhage score and blood PGF(2alpha) levels. Other parameters were unaffected by NAC. Exposure to CS causes severe histopathological changes and negatively effects the oxidant-antioxidant status in the lungs of rabbits. A low daily dose of NAC has some ameliorative effects on histopathological changes and oxidant-antioxidant status of the lungs in smoke exposed rabbits.

Endothelin receptor alterations in equine airway hyperreactivity

The purpose of this study was to evaluate the role of endothelin-1 (ET-1) and its receptors in the airway hyperreactivity of horses with obstructive pulmonary disease associated with summer pasture (SPAOPD). The right diaphragmatic lobe of the lung of 8 clinically healthy (unaffected) and 8 SPAOPD-affected horses was collected immediately after euthanasia. Bronchial rings (4 mm wide) were prepared and mounted in organ baths and attached to force transducers interfaced with a polygraph. Four rings were used to study each ET-1 receptor; 1 ring served as the control, and the other 3 were incubated with 10(-9), 10(-7), or 10(-5) M of either BQ-123, an ET(A)-receptor antagonist, or IRL-1038, an ET(B)-receptor antagonist. Cumulative concentrations (10(-8.5) to 10(-6) M) of ET-1 were applied to all rings. Using pooled pulmonary tissue from different regions of the lung, we performed a reverse-transcription polymerase chain reaction (RT-PCR) to determine ET(B)-receptor gene expression. Although ET-1 caused concentration-dependent bronchial ring contraction in both groups of horses, the rings of SPAOPD-affected horses had significantly greater contraction than the rings of unaffected horses. Whereas ET(A)-receptor blockade significantly increased the response to ET-1 in unaffected horses, ET(B)-receptor blockade significantly decreased the response in affected horses. The pA2 values showed a nonsignificant decrease in ET(A)-receptor affinity and a significant increase in ET(B)-receptor affinity in affected horses compared with unaffected horses. The ET(B)-receptor mRNA expression of the pooled pulmonary tissue showed a nonsignificant increase in affected horses compared with unaffected horses. The airway hyperreactivity to ET-1 observed in the bronchial rings from the affected horses appears to be due in part to activation of pulmonary ET(B) receptors, which appear to be inactive in unaffected horses.

Associations between health effects and particulate matter and black carbon in subjects with respiratory disease

We measured fractional exhaled nitric oxide (FE(NO)), spirometry, blood pressure, oxygen saturation of the blood (SaO2), and pulse rate in 16 older subjects with asthma or chronic obstructive pulmonary disease (COPD) in Seattle, Washington. Data were collected daily for 12 days. We simultaneously collected PM10 and PM2.5 (particulate matter < or = 10 microm or < or = 2.5 microm, respectively) filter samples at a central outdoor site, as well as outside and inside the subjects' homes. Personal PM10 filter samples were also collected. All filters were analyzed for mass and light absorbance. We analyzed within-subject associations between health outcomes and air pollution metrics using a linear mixed-effects model with random intercept, controlling for age, ambient relative humidity, and ambient temperature. For the 7 subjects with asthma, a 10 microg/m3 increase in 24-hr average outdoor PM10 and PM2.5 was associated with a 5.9 [95% confidence interval (CI), 2.9-8.9] and 4.2 ppb (95% CI, 1.3-7.1) increase in FE(NO), respectively. A 1 microg/m3 increase in outdoor, indoor, and personal black carbon (BC) was associated with increases in FE(NO) of 2.3 ppb (95% CI, 1.1-3.6), 4.0 ppb (95% CI, 2.0-5.9), and 1.2 ppb (95% CI, 0.2-2.2), respectively. No significant association was found between PM or BC measures and changes in spirometry, blood pressure, pulse rate, or SaO2 in these subjects. Results from this study indicate that FE(NO) may be a more sensitive marker of PM exposure than traditional health outcomes and that particle-associated BC is useful for examining associations between primary combustion constituents of PM and health outcomes.

Diagonal reverse-phase chromatography applications in peptide-centric proteomics: Ahead of catalogue-omics?

Diagonal electrophoresis/chromatography was described 40 years ago and was used to isolate specific sets of peptides from simple peptide mixtures such as protease digests of purified proteins. Recently, we have adapted the core technology of diagonal chromatography so that the technique can be used in so-called gel-free, peptide-centric proteome studies. Here we review the different procedures we have developed over the past few years, sorting of methionyl, cysteinyl, amino terminal, and phosphorylated peptides. We illustrate the power of the technique, termed COFRADIC (combined fractional diagonal chromatography), in the case of a peptide-centric analysis of a sputum sol phase sample of a patient suffering from chronic obstructive pulmonary disease (COPD). We were able to identify an unexpectedly high number of intracellular proteins next to known biomarkers.

[Determination of plasma and sputum substance P content in patients with chronic obstructive pulmonary disease or asthma]

OBJECTIVE

To investigate the role of substance P (SP) in chronic obstructive pulmonary disease (COPD) or asthma.

METHOD

Plasma and sputum samples were obtained from 26 COPD patients and 20 asthmatic patients as well as 12 healthy subjects for measurement of SP content.

RESULTS

Patients with COPD had significantly higher levels of SP in the plasma (7.9+/-2.6 pmol/L) and sputum (53.8+/-12.5 pmol/L) than the healthy subjects (3.6+/-1.7 pmol/L and 6.2+/-2.3 pmol/L, respectively, P<0.01). The asthmatic patients also had significantly higher SP levels (8.3+/-3.1 pmol/L and 46.9+/-10.2 pmol/L, respectively) than the healthy subjects, but there was no significant difference between COPD and asthmatic patients (P>0.05).

CONCLUSION

SP may be involved in the airway inflammation process in COPD and asthma.

Antioxidant and inflammatory responses of healthy horses and horses affected by recurrent airway obstruction to inhaled ozone

REASONS FOR PERFORMING STUDY

Inhaled ozone can induce oxidative injury and airway inflammation. Horses affected by recurrent airway obstruction (RAO) have a decreased pulmonary antioxidant capacity, which may render them more susceptible to oxidative challenge. It is currently unknown whether RAO-affected horses are more susceptible to oxidative stress than those unaffected by RAO.

OBJECTIVES

To determine whether ozone exposure induces greater oxidative stress and airway inflammation in RAO-affected horses in remission than in healthy horses.

METHODS

Seven healthy control horses and 7 RAO-affected horses were exposed to 0.8 ppm ozone for 2 h at rest.

RESULTS

At baseline, bronchoalveolar lavage fluid (BALF) ascorbic acid concentrations were lower in RAO-affected horses than healthy controls. Ozone appeared to preferentially oxidise glutathione rather than ascorbic acid 6 h after exposure. Individual healthy and RAO-affected horses demonstrated oxidation of BALF glutathione after ozone exposure. Overall, RAO-affected horses did not demonstrate increased oxidative stress following ozone exposure, compared with healthy horses. Ozone did not induce significant airway inflammation in either group.

CONCLUSIONS

RAO-affected horses in remission are not more sensitive to ozone despite a decreased pulmonary antioxidant capacity. Sensitivity to ozone appears to be independent of initial pulmonary antioxidant status.

POTENTIAL RELEVANCE

Horses with high susceptibility to oxidative stress may benefit from antioxidant supplementation.

Mycoplasma pneumoniae induces host-dependent pulmonary inflammation and airway obstruction in mice

Respiratory tract infections result in wheezing in a subset of patients. Mycoplasma pneumoniae is a common etiologic agent of acute respiratory infection in children and adults that has been associated with wheezing in 20-40% of individuals. The current study was undertaken to elucidate the host-dependent pulmonary and immunologic response to M. pneumoniae respiratory infection by studying mice with different immunogenetic backgrounds (BALB/c mice versus C57BL/6 mice). After M. pneumoniae infection, only BALB/c mice developed significant airway obstruction (AO) compared with controls. M. pneumoniae-infected BALB/c mice manifested significantly elevated airway hyperresponsiveness (AHR) compared with C57BL/6 mice 4 and 7 d after inoculation as well as BALB/c control mice. Compared with C57BL/6 mice, BALB/c mice developed worse pulmonary inflammation, including greater peribronchial infiltrates. Infected BALB/c mice had significantly higher concentrations of tumor necrosis factor-alpha, interferon-gamma, interleukin (IL)-1beta, IL-6, IL-12, KC (functional IL-8), and macrophage inflammatory protein 1alpha in the bronchoalveolar lavage fluid compared with infected C57BL/6 mice. No differences in IL-2, IL-4, IL-5, IL-10, and granulocyte/macrophage colony-stimulating factor concentrations were found. The mice in this study exhibited host-dependent infection-related AO and AHR associated with chemokine and T-helper type (Th)1 pulmonary host response and not Th2 response after M. pneumoniae infection.

[The levels and clinical implications of induced sputum interleukin-17 in chronic obstructive pulmonary disease and asthma]

OBJECTIVE

The study aims to investigate the changes of interleukin (IL)-17 in induced sputum, and to observe the correlation between concentrations of IL-17 and the number of inflammatory cells in induced sputum in chronic obstructive pulmonary disease (COPD) and in asthma.

METHODS

Induced sputum was obtained in patients with COPD both during acute exacerbation and stable stage and in asthma during acute attack. Healthy nonsmoking volunteers were included as controls. The concentrations of IL-17 in induced sputum were measured by enzyme-linked immunosorbent assay.

RESULTS

The concentrations of IL-17 both in patients with COPD during acute exacerbation and with asthma were significantly higher than that in the control subjects (P < 0.001). The levels of IL-17 in patients with COPD during acute exacerbation positively correlated with that of IL-8 (r = 0.381, P = 0.038) and with the percentage of neutrophils (r = 0.446, P = 0.010) respectively. There was also a positive correlation between the concentrations of IL-17 and the numbers of eosinophils in patients with asthma.

CONCLUSION

The concentrations of IL-17 in patients with acute exacerbation of COPD and in patients with asthma were significantly increased. IL-17 may play a role in the airway inflammation in both COPD and asthma.

Comparison of TGF-beta 1 concentrations in bronchoalveolar fluid of horses affected with heaves and of normal controls

Airway remodeling may play an important role in heaves pathophysiology. Transforming growth factor-beta 1 (TGF-beta1) is a potent profibrotic cytokine, which might contribute to airway wall thickening and fibrosis of bronchiolar and alveolar submucosa. An ELISA designed for the measurement of human TGF-beta1 was used to measured total TGF-beta1 released in bronchoalveolar lavage fluid (BALF) of normal horses and of those affected with heaves in remission. The specificity of the assay for TGF-beta1 of the horse was confirmed using recombinant equine TGF-beta1. The influence of hay exposure on TGF-beta1 release in the airways was also examined by stabling horses in a dusty environment. TGF-beta1 was found in the BALF of all horses. However, no significant difference between basal concentration of TGF-beta1 in BALF of control horses versus that of horses affected with heaves was found. Furthermore, no differences were identified in these populations 1 and 9 days after allergen challenge. In conclusion, these data indicate that TGF-beta1 is released in BALF fluid of horses in biologically active concentrations. Other studies are necessary for a better definition of the role of this cytokine within the lung, as our study does not establish a causal relationship between TGF-beta1 and the pathophysiology of heaves in the horse.

Exhaled markers of inflammatory lung diseases: ready for routine monitoring?

Assessing airway inflammation is important for investigating the underlying mechanisms of many lung diseases, including asthma and chronic obstructive pulmonary disease (COPD). Yet these are not measured directly in routine clinical practice because of the difficulties in monitoring inflammation. The presence and type of airway inflammation can be difficult to detect clinically, and may result in delays in initiating appropriate therapy. Non-invasive monitoring may assist in differential diagnosis of lung diseases, assessment of their severity and response to treatment. There is increasing evidence that breath analysis may have an important place in the diagnosis and clinical management of asthma, COPD, primary ciliary dyskinesia (PCD) and other major lung disease. The article reviews whether current noninvasive measurements of exhaled gases, such as nitric oxide (NO), hydrocarbons, inflammatory markers exhaled breath condensate (EBC) are ready for routine use in clinical practice.

[Smoking, the level of DNA adducts and chronic obstructive pulmonary diseases]

OBJECTIVE

To investigate the association between DNA adducts (DNA-BPDE) and smoking, and the association of DNA adducts with the development of chronic obstructive pulmonary disease (COPD).

METHODS

DNA-BPDE were tested with competitive enzyme-linked immunosorbent assay (ELISA) in passive smoking rats. DNA-BPDE were also tested in 68 people including smokers and non-smokers, and in 88 patients with COPD and 87 healthy smoking control subjects. Pre- and post-stimulation with benzo[a]pyrene diol epoxide (BPDE), DNA-BPDE of lymphocytes were tested in 20 patients with COPD and 20 healthy smoking control subjects. The dynamic process of apoptosis was analyzed by flow cytometry.

RESULTS

(1) Smoking and DNA-BPDE: (1) With more days of passive smoking, the level of DNA-BPDE in rats increased, the correlation coefficient being 0.90. (2) With increasing of smoking index, the level of DNA-BPDE increased in the 68 healthy people, the correlation coefficient being 0.67. (2) DNA-BPDE and COPD: In patients with COPD and the controls, DNA-BPDE (per 10(7) nucleotides) were 91 +/- 23 and 67 +/- 15, the difference being significant (P < 0.01). Pre- and post-stimulation with BPDE, the DNA-BPDE were 94.5 +/- 24.1 and 106.1 +/- 27.3 in the 20 patients with COPD, but these were 68.3 +/- 15.8 and 72.5 +/- 16.7 in the controls. The difference between pre- and post-stimulation in the COPD group and the healthy smoking control group was significant (P < 0.01). (3) The apoptosis rate of T-lymphocytes and B-lymphocytes were 18.5% +/- 3.1% and 5.8% +/- 0.6% in COPD, but were 9.5% +/- 1.8% and 5.2% +/- 0.7% in the healthy smoking control subjects, the difference being significant (P < 0.01).

CONCLUSIONS

There is a significant association between the levels of DNA-BPDE and smoking. DNA-BPDE may result in cell damage and cell apoptosis, and may contribute to the pathogenesis of COPD.

IL-4, IL-5 and IFN-gamma mRNA expression in pulmonary lymphocytes in equine heaves

Heaves is a common condition of horses of cold climate that is characterized by small airway inflammation and obstruction following exposure of susceptible horses to moldy hay and straw. It has been shown that helper T lymphocytes (Th) orchestrate the inflammatory response in asthma and in various animal models of allergic lung diseases by the release of Th2-type cytokines. Results of previous studies indicate that a predominant expression of Th2-type response by airway cells may also be present in heaves. To evaluate the temporal mRNA expression of Th1 (IFN-gamma) and Th2 (IL-4, IL-5) type cytokines in heaves and their relationship to clinical disease, we studied the pulmonary mechanics and cytokine mRNA expression (IL-4, IL-5 and IFN-gamma) in bronchoalveolar lavage lymphocytes of horses with heaves (n=6) and control (n=6) before and after 24h and 9 days of continuous natural inhalation challenge. Starting 24h after challenge horses with heaves, but not control horses, had a significant increase in pulmonary elastance and the number of lymphocytes expressing mRNA for IL-4 and IL-5. These changes were further increased at 9 days, at which time the number of cells positive for IFN-gamma mRNA was decreased. In this study we have shown that BAL lymphocytes of horses with heaves during clinical exacerbation have a predominant Th2-type cytokine response and that this response coincides in time with the presence of airway obstruction.

[Cyto-oxidant markers of inflammation in assessing the efficacy of differentiating therapy of severe obstructive pulmonary diseases]

The study purpose was the cytooxidant properties of inflammation in patients with severe heterogenic forms of chronic obstructive pulmonary disease (COPD); and the informative value of the changes in the studied indices for assessment of anti-inflammatory efficiency of differential therapy. The cytological test (CT) and chemiluminescent biotesting of bronchial lavage (CB) obtained with fibrobronchoscopy were conducted in 155 patients with severe bronchial asthma and chronic obstructive bronchitis. The patients were divided into groups according to current classification and predominant etiological factor of the exacerbation. The data of CT and CB in exacerbation significantly differ from the findings in the control group. They also differed in bronchial asthma and chronic obstructive bronchitis. The differentiated treatment resulted in improvement but did not reach the parameters of the control group. Thus, changes in CT and CB proved to be of the differentiated nature and this enables to use the tests as additional sensitive examinations in clinical practice.

[Expression of matrix metalloproteinases in lung tissue and levels of some cytokines in bronchoalveolar lavage fluid in the obstructive emphysema rat models]

OBJECTIVE

To observe the changes of matrix metalloproteinase-2 (MMP-2), MMP-9 and interleukin-10 (IL-10), tumor necrosis factor-alpha (TNFalpha) in lung tissue of the obstructive emphysema rat models and to evaluate the relationship between these changes and emphysema formation.

METHODS

The rat emphysema models were established by exposure to cigarette smoking. Pulmonary function tests were performed to evaluate the forced expiratory volume in 0.3 second (FEV(0.3)), FEV(0.3)/forced vital capacity (FVC) and functional residual capacity (FRC). The morphological indices of emphysema were measured by computer image analyzer. The protein expression and enzymatic activity of MMPs in lung tissue were observed. The contents of IL-10 and TNFalpha in bronchoalveolar lavage fluid (BALF) were measured.

RESULTS

Pulmonary function test showed that in model group the FEV(0.3)/FVC was decreased, whereas the FRC was increased significantly than those in control group (P < 0.01, respectively). There was a significant decrease in the relative content of elastin in lung tissue in model group than that in control group. The expression and enzymatic activity of MMP-2 and MMP-9 in lung tissue, the counts of total leukocytes and neutrophils and the level of TNFalpha in BALF were significantly elevated, but the level of IL-10 in BALF was significantly reduced in model group compared with those in control group (P < 0.01, respectively). There were statistically significant positive correlations between the enzymatic activity of MMP-2, MMP-9 and the total leukocyte counts (P < 0.01, respectively), and significant negative correlations between the enzymatic activity of MMP-2, MMP-9 and the content of elastin (P < 0.05, respectively).

CONCLUSIONS

MMP-2, MMP-9, IL-10 and TNFalpha may play an important role in the formation of obstructive emphysema in rat models caused by passive smoking.

Molecular cloning and characterization of spurt, a human novel gene that is retinoic acid-inducible and encodes a secretory protein specific in upper respiratory tracts

Retinoids, such as all-trans-retinoic acid, play an essential role in the regulation of airway epithelial cell growth, differentiation, and gene expression. Using cDNA microarray, we identified a clone, DD4, that contains the cDNA of a novel gene, spurt (secretory protein in upper respiratory tracts) that was significantly induced by all-trans-retinoic acid in primary cultured human tracheobroncheal epithelia. Two alternatively spliced spurt transcripts of 1090 and 1035 base pairs exist that contain the same open reading frame expressing a 256-amino acid peptide. The full-length spurt cDNA sequence spans a genomic DNA fragment of 7,313 bp, and the gene is located on chromosome 20q11.21. spurt mRNA is notably expressed at high levels in human nasal, tracheal, and lung tissues. In situ hybridization demonstrated that spurt message is often present in secretory cell types. The human spurt gene product is a secretory protein that contains a distinct signal peptide sequence in its first 19 amino acids. Mono-specific antibodies were generated to characterize spurt expression. Our data demonstrate that spurt is secreted onto the apical side of primary human airway epithelial cultures and is present in clinical sputum samples. spurt gene expression is higher in sputum and tissue samples obtained from patients with chronic obstructive lung disease. Our results provide the cloning and characterization of this tissue-specific novel gene and its possible relationship with airway diseases.

[The change in the activity of angiotensin converting enzyme in patients with pneumonia and chronic obstructive pulmonary diseases]

The activity of angiotensin-converting enzyme (ACE) was measured in the serum and bronchial contents of 69 patients with pneumonia and 77 with chronic obstructive pulmonary diseases (COPD). ACE activity was decreased both in the blood and bronchial contents during the acute phase of pneumonia. With resolution of the inflammatory process, ACE activity normalized. In patients with COPD, the activity of ACE is decreased during remission in comparison with the mean values in the population. During COPD exacerbation the activity of ACE increases both in the blood and bronchial contents. Changes in ACE activity in pneumonia and COPD are more pronounced in the bronchial contents than in the blood. Presumably alteration of the enzyme concentration is the only cause of alteration of its activity in patients with COPD and pneumonia.

[Clinical polymorphism in respiratory oxalosis]

AIM

Examination of clinical polymorphism of chronic obstructive pulmonary diseases (COPD) in defects of oxalate metabolism to make diagnostic outpatient screening of the preclinical stage.

MATERIAL AND METHODS

Diagnostic dysgenetic markers of respiratory oxalosis (RO)--red hair in monthers and 24-h oxaluria--were studied in 28 women and 7 men. 8 women (group 1) had diagnostic association, 7 women (group 2) had no hereditary marker, 13 women (group 3) had no signs of disturbed oxalate metabolism. In addition, families of group 1 patients were examined for preclinical signs of visceral oxalosis in close relatives (kinship degree I). A comparison was made of quantitative enzyme assay of registering 24-h oxaluria (Lartillot M. et Vogel G) and titration by G. A. Sivorinovsky.

RESULTS

Group 1 COPD patients with mild disease had rather high 24-h oxaluria. In group 2 and 3 patients oxaluria was significantly lower. Dysgenetic markers--24-h oxaluria with the hereditary criterium--may be used in differential diagnosis of RO with its phenocopy having a more severe course at preclinical stage. Male relatives of kinship degree I had significant differences with group 1 patients in 24-h oxaluria, oxaluria was combined with clinical symptoms of acid, uratic diathesis.

CONCLUSION

The enzyme assay of oxalate in 24-h urine in combination with hereditary marker is an adequate screening method for preclinical stage of RO. The presence of various clinical manifestations of visceral oxalosis--RO and acid, uratic diathesis in the family--may indicate clinical polymorphism of mutant gene.

[Serotonin level in endocrine cells in bronchial mucosa and stomach in chronic obstructive lung diseases]

85 patients aged 26-60 years with pulmonary chronic obstructive diseases (PCOD) and gastric and duodenal erosive-ulcerous lesions were investigated. In PCOD the increased bioamines level in endocrine cells of bronchial ciliated epithelium and gastric glandular epithelium was detected before the treatment. The complex treatment in the form of bronchoscopy with lymphotropic administration of antibiotic and immunomodulator against the background of intragastral ozonotherapy contributes to the decrease in tissue edema, restoration of their trophicity and inflammatory process resolution. Against the background of therapy the serotonin content in endocrine cells of bronchial ciliated epithelium and gastric mucosa decreased to the norm.

Oxidative stress and lung inflammation in airways disease

Oxidative stress results from an oxidant/antioxidant imbalance in favour of oxidants. A large number of studies have demonstrated that increased oxidative burden occurs in airways diseases, shown by increased marks of oxidative stress in the airspaces and systemically in these patients. There is now substantial evidence that oxidative stress plays an important role in the injurious and inflammatory responses in airways diseases such as asthma and chronic obstructive pulmonary disease (COPD). In addition to these proinflammatory mechanisms resulting from oxidative stress, protective mechanisms such as the upregulation of protective antioxidant genes also occur. At present, effective antioxidant therapy that has good bioavailability and potency is not available. Such drugs are being developed and should in the future allow the hypothesis that oxidative stress is a fundamental factor in the inflammation, which occurs in these airways diseases to be tested.

Pilot detection study of alpha(1) antitrypsin deficiency in a targeted population

Screenings for the genetic disorder alpha(1) antitrypsin deficiency (AAT Deficiency) have been one of two models: large screenings of general populations and small targeted detection programs in high-risk groups. The most appropriate screening and detection methodologies in terms of target populations, subject participation and yield of positive tests, however, have not been well defined. The major objective of this pilot study was to evaluate the effectiveness in terms of participation of two different AAT Deficiency detection programs using a self-administered fingerstick blood test. Individuals ages 30-60 under the care of a pulmonary physician and with a diagnosis of emphysema, COPD, chronic bronchitis, or bronchiectasis were the targeted population. Participants were offered AAT Deficiency testing in the pulmonary physician's office compared with testing offered through mail. Participation (i.e., frequency of subject participation in the detection program) of two different AAT Deficiency detection programs. Non-participation was due to fear of self-administered testing and research studies; women were more likely to participate than men. Eligible subjects were significantly more likely to participate when offered testing by their pulmonary physician in-office (83%) than mail-only (42%) (P < 0.02). Although self-administered genetic testing is available, highest participation in AAT Deficiency detection program was found when offered directly by the physician. This finding may have implications for screening and detection of other genetic diseases. Future studies need to evaluate the yield (i.e., frequency of positive tests) of these detection methodologies in highly targeted populations.

[New techniques in artificial ventilation]

In recent years, considerable improvement has been achieved in the field of mechanical ventilation. A lot of experimental and clinical research has been done to reduce the adverse effects of mechanical ventilation. It is currently of importance that high volumes and pressures have been demonstrated as sources of alveolar-capillary membrane injury in lungs. In the acute respiratory distress syndrome, mechanical ventilator settings have evolved from the goal of strict correction of gas exchange towards a lung-protective strategy where priority is given to tidal volumes limitation and alveolar recruitment. Pressure-assisted ventilatory modes, such as pressure support have been introduced, resulting in better patient-ventilator synchronisation, good tolerance and easier weaning process. Pressure support is also a largely used mode in noninvasive ventilation which has been proved to improve outcome in chronic obstructive pulmonary diseases.

Plasma and bronchoalveolar fluid concentrations of nitric oxide and localization of nitric oxide synthesis in the lungs of horses with summer pasture-associated obstructive pulmonary disease

OBJECTIVE

To determine concentrations of nitric oxide (NO) in plasma and bronchoalveolar lavage fluid (BALF) and localize nitric oxide synthesis in the lungs of horses with summer pasture-associated obstructive pulmonary disease (SPAOPD).

ANIMALS

7 adult horses with SPAOPD and 6 clinically normal adult horses.

PROCEDURE

Severity of SPAOPD was determined by use of clinical scores, change in intrapleural pressure (APpl) during tidal breathing, cytologic analysis of BALF, and histologic evaluation of lung specimens obtained during necropsy. Nitric oxide concentrations in plasma, BALF and epithelial lining fluid (ELF) were determined by use of a chemiluminescent method. Inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT) were localized in formalin-fixed lung specimens by use of immunohistochemical staining, and nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) activity was localized in cryopreserved specimens by use of histochemical staining.

RESULTS

Plasma concentration of NO in affected horses was slightly but not significantly greater than concentration in nonaffected horses. Nitric oxide concentrations in BALF or ELF did not differ between groups. Immunoreactivity of iNOS in bronchial epithelial cells of 3 of 5 lung lobes was greater in horses with SPAOPD, compared with nonaffected horses. However, staining for NT and NADPHd activity did not differ between groups.

CONCLUSIONS AND CLINICAL RELEVANCE

Expression of iNOS was greater in bronchial epithelial cells of horses with SPAOPD, compared with nonaffected horses, suggesting that NO may play a role in amplifying the inflammatory process in the airways of horses with this disease.

Systemic anti-inflammatory mediators in COPD: increase in soluble interleukin 1 receptor II during treatment of exacerbations

BACKGROUND

The aim of this study was to test the hypothesis that the chronic inflammatory process present in chronic obstructive pulmonary disease (COPD) is due to a defective endogenous anti-inflammatory mechanism.

METHODS

Systemic levels of the anti-inflammatory mediators soluble interleukin 1 receptor II (sIL-1RII), soluble tumour necrosis factor receptor p55 (sTNF-R55) and sTNF-R75, and of C reactive protein (CRP) and lipopolysaccharide binding protein (LBP) were analysed in 55 patients with stable COPD (median forced expiratory volume in one second (FEV(1)) 34% predicted (range 15-78)) and compared with levels in 23 control subjects. In addition, changes in these mediators were studied in 13 patients with COPD (median FEV(1) 34% predicted (range 19-51)) during the first 7 days in hospital with an exacerbation of the disease.

RESULTS

Patients with stable COPD were characterised by a systemic inflammatory process indicated by an increased leucocyte count (7.2 (4.7-16.4) v 4.8 (3.5-8.3) x 10(9)/l), raised levels of CRP (11.8 (1.1-75.0) v 4.1 (0.6-75.0) microg/ml) and LBP (45.6 (8.1-200.0) v 27.9 (14.1-71.5) microg/ml), and moderate increases in both sTNF-Rs. In contrast, the sIL-1RII level did not differ between patients and controls (4.53 (2.09-7.60) v 4.63 (3.80-5.93) ng/ml). During treatment of disease exacerbations, systemic levels of both CRP (at day 3) and LBP (at day 7) were significantly reduced compared with day 1, whereas sIL-1RII levels increased.

CONCLUSIONS

These data suggest an imbalance in systemic levels of pro- and anti-inflammatory mediators in patients with stable COPD. The increase in the anti-inflammatory mediator sIL-1RII during treatment of exacerbations may contribute to the clinical improvement.

Marked sympathetic activation in patients with chronic respiratory failure

The autonomic nervous system may be disturbed in chronic respiratory failure. We tested the hypothesis that there is increased sympathetic activity in patients with chronic hypoxemia. Furthermore, we examined the effect of short-term oxygen on muscle sympathetic nerve activity (MSNA) in these patients. We performed microneurography of the peroneal nerve in 11 patients with hypoxemia due to chronic obstructive pulmonary disease (COPD, n = 6) or lung fibrosis (n = 5) and in 11 healthy subjects matched for age and sex. MSNA was measured during normal breathing in all subjects. In eight patients and in seven control subjects, MSNA was also measured during nasal oxygen (4 L/min). MSNA was higher in the patients with chronic respiratory failure compared with the healthy subjects during normal breathing (61 +/- 5 versus 34 +/- 2 bursts/min, mean +/- SEM; p = 0.0002, paired t test). During oxygen administration, MSNA decreased from 63 +/- 6 to 56 +/- 6 bursts/min in the patients (p = 0.0004, ANOVA); there was no change in sympathetic activity in the control subjects. For the first time, there is direct evidence of marked sympathetic activation in patients with chronic respiratory failure. This is partly explained by arterial chemoreflex activation and may play an important role in the pathogenesis of the disease.