Inhibiting pollen reduced nicotinamide adenine dinucleotide phosphate oxidase-induced signal by intrapulmonary administration of antioxidants blocks allergic airway inflammation

BACKGROUND

Ragweed extract (RWE) contains NADPH oxidases that induce oxidative stress in the airways independent of adaptive immunity (signal 1) and augment antigen (signal 2)-induced allergic airway inflammation.

OBJECTIVE

To test whether inhibiting signal 1 by administering antioxidants inhibits allergic airway inflammation in mice.

METHODS

The ability of ascorbic acid (AA), N-acetyl cystenine (NAC), and tocopherol to scavenge pollen NADPH oxidase-generated reactive oxygen species (ROS) was measured. These antioxidants were administered locally to inhibit signal 1 in the airways of RWE-sensitized mice. Recruitment of inflammatory cells, mucin production, calcium-activated chloride channel 3, IL-4, and IL-13 mRNA expression was quantified in the lungs.

RESULTS

Antioxidants inhibited ROS generation by pollen NADPH oxidases and intracellular ROS generation in cultured epithelial cells. AA in combination with NAC or Tocopherol decreased RWE-induced ROS levels in cultured bronchial epithelial cells. Coadministration of antioxidants with RWE challenge inhibited 4-hydroxynonenal adduct formation, upregulation of Clca3 and IL-4 in lungs, mucin production, recruitment of eosinophils, and total inflammatory cells into the airways. Administration of antioxidants with a second RWE challenge also inhibited airway inflammation. However, administration of AA+NAC 4 or 24 hours after RWE challenge failed to inhibit allergic inflammation.

CONCLUSION

Signal 1 plays a proinflammatory role during repeated exposure to pollen extract. We propose that inhibiting signal 1 by increasing antioxidant potential in the airways may be a novel therapeutic strategy to attenuate pollen-induced allergic airway inflammation.

CLINICAL IMPLICATIONS

Administration of antioxidants in the airways may constitute a novel therapeutic strategy to prevent pollen induced allergic airway inflammation.

House cleaning with chlorine bleach and the risks of allergic and respiratory diseases in children

Chlorine bleach or sodium hypochlorite can inactivate common indoor allergens. In this cross-sectional study we evaluated to what extent regular house cleaning with bleach can influence the risks of respiratory and allergic diseases in children. We studied a group of 234 schoolchildren aged 10-13 yr among whom 78 children were living in a house cleaned with bleach at least once per week. Children examination included a questionnaire, an exercise-induced bronchoconstriction test and the measurement of exhaled nitric oxide (NO) and of serum total and aeroallergen-specific immunoglobulin (Ig)E, Clara cell protein (CC16) and surfactant-associated protein D (SP-D). Children living in a house regularly cleaned with bleach were less likely to have asthma (OR, 0.10; CI, 0.02-0.51), eczema (OR, 0.22; CI, 0.06-0.79) and of being sensitized to indoor aeroallergens (OR, 0.53; CI, 0.27-1.02), especially house dust mite (OR, 0.43; CI, 0.19-0.99). These protective effects were independent of gender, ethnicity, previous respiratory infections, total serum IgE level and of family history of allergic diseases. They were however abolished by parental smoking, which also interacted with the use of bleach to increase the risk of recurrent bronchitis (OR, 2.03; CI, 1.12-3.66). House cleaning with bleach had effect neither on the sensitization to pollen allergens, nor on the levels of exhaled NO and of serum CC16 and SP-D. House cleaning with chlorine bleach appears to protect children from the risks of asthma and of sensitization to indoor allergens while increasing the risk of recurrent bronchitis through apparently an interaction with parental smoking. As chlorine bleach is one of the most effective cleaning agent to be found, these observations argue against the idea conveyed by the hygiene hypothesis that cleanliness per se increases the risk of asthma and allergy.

Comparison of the mucosal immune response in dogs vaccinated with either an intranasal avirulent live culture or a subcutaneous antigen extract vaccine of Bordetella bronchiseptica

Healthy dogs with low antibody titer to Bordetella bronchiseptica were vaccinated intranasally with an avirulent live vaccine, subcutaneously with an antigen extract vaccine, or subcutaneously and intranasally with a placebo. Intranasally vaccinated dogs developed B. bronchiseptica-specific IgA titers in nasal secretions that remained at high levels until the end of the study; dogs vaccinated subcutaneously with the antigen extract or placebo did not develop measurable antigen-specific IgA titers in nasal secretions. Dogs were challenged with virulent live B. bronchiseptica 63 days after vaccination. Intranasally vaccinated dogs had significantly lower cough scores (P < or =.0058) and shed significantly fewer challenge organisms (P <.0001) than dogs in either of the other groups. Cough scores of subcutaneously vaccinated dogs were not significantly different from placebo-vaccinated dogs.

Arsenic trioxide, a potent inhibitor of NF-kappaB, abrogates allergen-induced airway hyperresponsiveness and inflammation

Background

Overactivation of nuclear factor κB (NF-κB) orchestrates airway eosinophilia, but does not dampen airway hyperresponsiveness in asthma. NF-κB repression by arsenic trioxide (As₂O₃) contributes to apoptosis of eosinophils (EOS) in airways. Here we provide evidence that As₂O₃ abrogates allergen (OVA)-induced airway eosinophilia by modulating the expression of IκBα, an NF-κB inhibitory protein, and decreases the airway hyperresponsiveness.

Methods

Using a murine model of asthma, the airway hyperresponsiveness was conducted by barometric whole-body plethysmography. Airway eosinophilia, OVA-specific IgE in serum, and chemokine eotaxin and RANTES (regulated upon activation, normal T cell expressed and secreted) in bronchoalveolar lavage fluid were measured by lung histology, Diff-Quick staining, and ELISA. Chemokine-induced EOS chemotactic activity was evaluated using EOS chemotaxis assay. Electrophoretic mobility shift assay and Western blot analysis were performed to assess pulmonary NF-κB activation and IκBα expression, respectively.

Results

As₂O₃ attenuated the allergen-induced serum IgE, chemokine expression of eotaxin and RANTES, and the EOS recruitment in bronchoalveolar lavage fluid, which is associated with an increased IκBα expression as well as a decreased NF-κB activation. Also, As₂O₃ suppressed the chemotaxis of EOS dose-dependently in vitro. Additionally, As₂O₃ significantly ameliorated the allergen-driven airway hyperresponsiveness, the cardinal feature underlying asthma.

Conclusion

These findings demonstrate an essential role of NF-κB in airway eosinophilia, and illustrate a potential dissociation between airway inflammation and hyperresponsiveness. As₂O₃ likely exerts its broad anti-inflammatory effects by suppression of NF-κB activation through augmentation of IκBα expression in asthma.

Infants fed docosahexaenoic acid- and arachidonic acid-supplemented formula have decreased incidence of bronchiolitis/bronchitis the first year of life

To assess the effect of docosahexaenoic acid and arachidonic acid supplementation in infant formula on the incidence of respiratory illnesses, pediatricians assigned infants to receive docosahexaenoic acid/arachidonic acid-supplemented formula or control formula. Anthropometrics, medical history, and illnesses were reported. Among 1342 infants, there was a higher incidence of bronchiolitis in control versus docosahexaenoic acid/arachidonic acid-supplemented groups at 5, 7, and 9 months (P < .01). Weight, length, and head circumference were similar for both groups. Infants fed formula supplemented with 0.32% docosahexaenoic acid and 0.64% arachidonic acid experienced a lower incidence of bronchiolitis compared with infants fed formula supplemented with no docosahexaenoic acid/arachidonic acid or lower levels of docosahexaenoic acid/arachidonic acid in the first year of life.

Haemophilus influenzae oral whole cell vaccination for preventing acute exacerbations of chronic bronchitis

BACKGROUND

Acute bronchitis leading to ongoing exacerbations is a serious condition predisposed to by viruses, bacteria or environmental factors. It can be fatal. Antibiotic therapy is not particularly useful. An oral Haemophilus influenzae vaccine has been developed.

OBJECTIVES

To assess the effects of an oral, monobacterial whole-cell, killed, nontypeable H. influenzae vaccine in protecting against recurrent acute episodes in chronic bronchitis.

SEARCH STRATEGY

In this updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to January Week 4 2006), EMBASE (1990 to September 2005) and ISI Current Contents (2004 to May 2006).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the effects of the H. influenzae vaccine on patients with recurrent acute exacerbations of chronic bronchitis were included when there was overt matching of the vaccine and placebo groups on clinical grounds.

DATA COLLECTION AND ANALYSIS

Three authors extracted data and assessed trial quality independently from original records and publications for incidence and severity of bronchitis episodes and carriage rate of nontypeable H. influenzae measured in the upper respiratory tract every three months following vaccination.

MAIN RESULTS

Six trials were included in the study with a total of 440 participants. The vaccine reduced the incidence of bronchitic episodes at three months after vaccination (rate ratio is 0.69; 95% CI 0.41 to 1.14) and at six months after vaccination (rate ratio 0.82; 95% CI 0.62 to 1.09). If these results been statistically significant, they would have represented a reduction in acute bronchitic attacks for vaccinated individuals of 31% at three months, and 18% at six. The effect had disappeared by nine months. The severity of exacerbations in the treatment group, as measured by requirement to prescribe antibiotics, was likewise reduced by 58% at three months (Peto odds ratio = 0.42; 95% CI 0.16 to 1.13), and by 65% at six months (Peto odds ratio = 0.35; 95% CI 0.16 to 0.75).

AUTHORS' CONCLUSIONS

Vaccinating patients with recurrent acute exacerbations of chronic bronchitis in the autumn may reduce the number and severity of exacerbations over the following winter. A large clinical trial is needed.

Oral bacterial vaccines for the prevention of acute exacerbations in chronic obstructive pulmonary disease and chronic bronchitis

Oral vaccines using killed bacterial extracts have been used to prevent acute exacerbations of chronic obstructive pulmonary disease (COPD); however, they are not recommended by current clinical guidelines. Two systematic reviews have been published on the efficacy of oral vaccines. The first, on the effects of an oral whole-cell nontypeable Haemophilus influenzae vaccine (NTHi) found a significant decrease in the incidence of acute episodes of chronic bronchitis (Poisson rate ratio 0.666; 95% confidence interval (CI) 0.500, 0.887; P = 0.005), and a 58% reduction in the prescription of antibiotics 3 months after vaccination. The second review evaluated studies that used multicomponent vaccines. It found that the duration of exacerbations was significantly shorter in the treatment group (weighted mean difference -2.7 days, 95% CI -3.5 to -1.8). These reviews suggest that oral vaccines reduce the number, severity, duration, or both, of acute exacerbations. However, many of the primary trials on which they are based are small and methodologically flawed. Further trials are needed before the use of oral vaccines could be considered as part of the routine clinical management of patients with COPD or chronic bronchitis.

Effects of ciclamilast, a new PDE 4 PDE4 inhibitor, on airway hyperresponsiveness, PDE4D expression and airway inflammation in a murine model of asthma

PDE4 (phosphodiesterase-4) plays a critical role in pathogenesis of allergic asthma and chronic obstructive pulmonary disease (COPD). PDE4 inhibitors are presently under clinical development for the treatment of asthma and/or COPD. Ciclamilast, a new PDE4 inhibitor, is a piclamilast (RP 73401) structural analogue, but has a more potent inhibitory effect on PDE4 and inflammation in the airway tissues and less side effects than that of piclamilast. In this study, we elucidate primarily on the roles of compound on PDE4 enzyme in physiological and pathological processes in a mouse model of asthma. The sensitized/challenged mice were reexposed to ovalbumin and airway response to inhaled methacholine was monitored. Orally administration of ciclamilast, in a dose-dependent manner, significantly inhibited changes in lung resistance and lung dynamic compliance, as well as upregulation of cAMP-PDE activity, increase of PDE4D mRNA expression, but not PDE4B from lung tissue in the murine model. In addition, the compound dose-dependently reduced mRNA expression of eotaxin, tumor necrosis factor (TNF)-alpha and interleukin (IL)-4, but slightly increased mRNA expression of interferon (IFN)-gamma from lung tissue. Further, levels of eotaxin, TNF-alpha and IL-4, and eosinophil and neutrophil accumulation in bronchoalveolar lavage fluid were also significantly reduced. Pathological examination, goblet cell hyperplasia and inflammatory cells infiltration in lung tissue were suppressed by treatment with ciclamilast. A significant correlation was observed between the increases in PDE4D mRNA expression and airway hyperresponsiveness. These studies confirm that inhibitory effect of ciclamilast on airway hyperresponsiveness includes its inhibiting PDE4D mRNA expression, down-modulating PDE4 activity, anti-inflammation and anti-mucus hypersecretion, and ciclamilast may have therapeutic potential for the treatment of asthma.

One-year evaluation of the preventative effect of hydrofluoroalkane-beclomethasone dipropionate on eosinophilic inflammation of asthmatic peripheral airways

BACKGROUND

In asthmatic patients with eosinophilic inflammation of the peripheral airways, appropriate drug delivery to the affected area is required.

OBJECTIVE

It was the aim of this study to assess persistent eosinophilic inflammation of the peripheral airways in asthmatic patients, stabilized by the long-term use of dry powder type inhaled steroids, and to evaluate the clinical efficacy of hydrofluoroalkane-beclomethasone dipropionate (HFA-BDP) over 1 year.

METHODS

Seventy-four outpatients with moderate stable asthma were studied for at least 6 months, 37 treated with fluticasone propionate Diskus (FP-DK) and 37 with budesonide Turbuhaler (BUD-TH). The eosinophil count, eosinophil cationic protein (ECP), eotaxin and RANTES levels in 10% hypertonic saline-induced sputum were examined before treatment, as well as 4 weeks, 8 weeks, 6 months and 1 year after switching patients to HFA-BDP.

RESULTS

Fifteen patients (40.5%) in the FP-DK group and 12 (32.4%) in the BUD-TH group had eosinophils in induced sputum. The sputum ECP in the eosinophil-positive and the eosinophil-negative groups was 1,510.1 +/- 2,009.3 versus 426.6 +/- 464.1 microg/l (p = 0.037) in the FP-DK group, and 3,850.0 +/- 5,486.2 versus 492.0 +/- 1,150.7 microg/l (p = 0.011) in the BUD-TH group, respectively. Four weeks after the switch to HFA-BDP, the number of eosinophil-positive patients decreased in both groups. Significant reductions in sputum ECP and eotaxin were observed at 8 weeks, and their concentrations continued decreasing for 1 year.

CONCLUSION

There is a certain proportion of asthmatic patients for whom long-term treatment with dry powder type steroids may not be suitable; however, their peripheral airway inflammation improved after switching them to HFA-BDP, suggesting its excellent delivery.

[Investigation of the risk factors and prevention of nosocomial tracheobronchitis in elderly patients on mechanical ventilation in surgical intensive care unit]

OBJECTIVE

To investigate the incidence, the risk factors and the outcome of nosocomial tracheobronchitis (NTB) in patients age over 65 years of age receiving mechanical ventilation (MV).

METHODS

Using prospective cohort study to collect and analyse the clinical information of elderly patients who received mechanical ventilation in surgical intensive care unit (ICU) of Zhongshan Hospital, from November 2002 to July 2004. Patients with first episodes of NTB were compared with those without NTB by univariate analysis and logistic regression.

RESULTS

There were 35 elderly patients diagnosed as having NTB (53.0%). The differences in serum albumin, nasal feeding, the length of ICU stay, the duration of MV days, the acute physiology and chronic health evaluation II (APACHE II) score and the kinds of the antibiotic used between patients with NTB and without NTB were significant. The results of the univariate analysis showed that nasal feeding, low serum albumin, the duration of the MV>4 days, the length of ICU stay >9 days, the kinds of antibiotics used and the APACHE II score higher than 9 were the risk factors of NTB. However the logistic regression suggested that nasal feeding, MV days >4 days, nasal feeding and the kinds of the antibiotics used >2 are the independent risk factors of NTB.

CONCLUSION

There is high incidence of NTB in ventilated patients in surgical ICU. Low albumin level, nasal feeding, prolonged MV and ICU stay days, high APACH II score and administration of too much antibiotics are the important risk factors of NTB.

[Using antibiotics in case of influenza]

Acute respiratory bacterial infection is the most common complication of influenza and a leading cause for excess rate of outpatient visits, hospitalization, and death (pneumonia). Influenza promotes bacterial infection as stated by epidemiologic evidence of temporal association between outbreaks or peaks of both influenza and bacterial pneumonia. The bacteria involved are Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus. However, Gram-negative rods, Klebsiella pneumoniae, Pseudomonas aeruginosa, anaerobes and methicillin resistant S. aureus may be involved in institutionalized elderly patients. Various studies confirm that antibiotics are over-prescribed in patients with influenza or influenza like illness, even in the absence of bacterial infection signs, and in patients without comorbidity. No data has proven the benefice of antibiotic prescription in influenza-infected patients without bacterial infection. Neuraminidase inhibitors may be of interest for the management of influenza infected patients, because they can decrease the risk of bacterial complications and the use of antibiotics.

The avoidable health effects of air pollution in three Latin American cities: Santiago, São Paulo, and Mexico City

Urban centers in Latin American often face high levels of air pollution as a result of economic and industrial growth. Decisions with regard to industry, transportation, and development will affect air pollution and health both in the short term and in the far future through climate change. We investigated the pollution health consequences of modest changes in fossil fuel use for three case study cities in Latin American: Mexico City, Mexico; Santiago, Chile; and São Paulo, Brazil. Annual levels of ozone and particulate matter were estimated from 2000 to 2020 for two emissions scenarios: (1) business-as-usual based on current emissions patterns and regulatory trends and (2) a control policy aimed at lowering air pollution emissions. The resulting air pollution levels were linked to health endpoints through concentration-response functions derived from epidemiological studies, using local studies where available. Results indicate that the air pollution control policy would have vast health benefits for each of the three cities, averting numerous adverse health outcomes including over 156,000 deaths, 4 million asthma attacks, 300,000 children's medical visits, and almost 48,000 cases of chronic bronchitis in the three cities over the 20-year period. The economic value of the avoided health impacts is roughly 21 to 165 billion Dollars (US). Sensitivity analysis shows that the control policy yields significant health and economic benefits even with relaxed assumptions with regard to population growth, pollutant concentrations for the control policy, concentration-response functions, and economic value of health outcomes. This research demonstrates the health and economic burden from air pollution in Latin American urban centers and the magnitude of health benefits from control policies.

Staged bilateral stereotactic pallidothalamotomy for life-threatening dystonia in a child with Hallervorden-Spatz disease

Hallervorden-Spatz disease (HSD) is a rare disorder characterized by progressive motor dysfunction and dementia. Dystonia is the most prominent and disabling symptom, responding only to a modest extent to pharmacological therapy. At the moment, only a few cases have been reported to improve dystonia and even fewer to resolve status dystonicus for a longer period in children. The authors present the case of a 10-year-old boy who had progressive generalized dystonia, resulting in spontaneous femur fracture and life-threatening swallowing and respiratory disability. As a rescue solution, staged bilateral pallidothalamotomy was performed. Postoperatively, Burke-Fahn-Marsden Dystonia Rating Scale and Dystonia Disability Rating Scale improved (from 116 and 30 points to 41 and 18 points, respectively) and painful dystonia was resolved, which was still continuous 4 years later (47 and 20 points). Stereotactic staged bilateral pallidothalamotomy should be considered as a potential treatment in the management of life-threatening generalized dystonia related to HSD.

The incidence of respiratory symptoms and diseases among pulp mill workers with peak exposures to ozone and other irritant gases

OBJECTIVES

Pulp mills in Sweden started to use ozone as a bleaching agent in the early 1990s. The goal of this study was to investigate whether the incidence of selected respiratory outcomes was associated with peak exposures to ozone or other irritant gases (ie, chlorine dioxide [ClO2] or sulfur dioxide [SO2]) used in these mills.

METHODS

Bleachery workers (n = 245) from three pulp mills where ozone was used participated in surveys in the mid- to late-1990s. Comparison workers (n = 80) were from two adjacent paper mills. The person-time at risk was calculated for each participant, covering the period of employment when ozone was used. Data were collected by questionnaire, and a peak exposure was defined as a self-reported exposure to an irritant gas resulting in acute respiratory symptoms. The outcomes analyzed were self-reports of physician-diagnosed asthma, attacks of wheeze, and chronic bronchitis (ie, chronic cough with phlegm). Participants also reported when the peak exposures and outcomes occurred.

RESULTS

Based on proportional hazards regression (controlling for gender, age, cigarette smoking, atopy, and peak irritant exposures that occurred before follow-up), workers who reported both ozone and ClO2/SO2 peak exposures had elevated hazard ratios (HRs) for all three outcomes. Those who reported only ozone peak exposures had elevated HRs of 6.5 (95% confidence interval [CI], 1.2 to 36.3) for asthma and 3.3 (95% CI, 1.1 to 10.2) for attacks of wheeze but no increase in risk for chronic bronchitis. Workers with only ClO2/SO2 peak exposures had elevated HRs for attacks of wheeze (HR, 7.5; 95% CI, 1.9 to 29.3) and chronic bronchitis (HR, 22.9; 95% CI, 4.5 to 118.2) but not for asthma.

CONCLUSIONS

These findings suggest the need for additional efforts to prevent peak exposures in pulp-bleaching operations.

Inhalation of stable dust extract prevents allergen induced airway inflammation and hyperresponsiveness

BACKGROUND

Recent epidemiological studies have shown that growing up on a traditional farm provides protection from the development of allergic disorders such as hay fever and allergic asthma. We present experimental evidence that substances providing protection from the development of allergic diseases can be extracted from dust collected in stables of animal farms.

METHODS

Stable dust was collected from 30 randomly selected farms located in rural regions of the Alps (Austria, Germany and Switzerland). The dust was homogenised with glass beads and extracted with physiological sodium chloride solution. This extract was used to modulate immune response in a well established mouse model of allergic asthma.

RESULTS

Treatment of mice by inhalation of stable dust extract during sensitisation to ovalbumin inhibited the development of airway hyperresponsiveness and airway eosinophilia upon challenge, as well as the production of interleukin 5 by splenocytes and of antigen specific IgG(1) and IgE. Dust extract also suppressed the generation of human dendritic cells in vitro. The biological activity of the dust extract was not exclusively mediated by lipopolysaccharide.

CONCLUSIONS

Stable dust from animal farms contains strong immune modulating substances. These substances can interfere with the development of both cellular and humoral immunity against allergens, thus suppressing allergen sensitisation, airway inflammation, and airway hyperresponsiveness in a murine model of allergic asthma.

Inhibition of p38 mitogen activated protein kinase controls airway inflammation in cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) airways are characterised by chronic inflammation, increased interleukin (IL)-8 secretion, and neutrophil activation which are considered the principal factors of morbidity and mortality in CF patients. Optimising management of this chronic inflammatory response is therefore a key issue of basic and clinical CF research. Several reports have addressed ways to manage CF airways inflammation, and an attractive therapeutic strategy may be the inhibition of the p38-mitogen activated protein kinase (p38-MAP-k) pathway.

METHODS

A new ex vivo model was used to study the mucosal inflammatory response to environmental airways stimuli. Nasal biopsy tissues from CF patients and controls were cultured ex vivo for 20 minutes, 4 hours, and 24 hours in the presence of lipopolysaccharide (LPS) from Pseudomonas aeruginosa (PA) with and without the p38-MAP-k inhibitor SB203580. Quantitative mRNA assessment, immunohistochemistry, and Western blots were used to detect the expression and modulation of inflammatory markers.

RESULTS

PA-LPS challenge induced a time dependent mucosal inflammation indicated by rapid epithelial activation, IL-8 release, COX-2 upregulation, and neutrophil migration to the upper mucosal layers. Some of these LPS induced changes (IL-8 release and neutrophil migration) were specific to CF tissues. SB203580 significantly controlled all LPS induced mucosal changes in CF tissues.

CONCLUSION

These findings provide a rationale and proof of principle for the potential use of p38-MAP-k inhibitors to control inflammation in patients with CF.

Protective role of metallothionein in acute lung injury induced by bacterial endotoxin

BACKGROUND

Metallothionein (MT) is a protein that can be induced by inflammatory mediators and participate in cytoprotection. However, its role in inflammation remains to be established. A study was undertaken to determine whether intrinsic MT protects against acute inflammatory lung injury induced by bacterial endotoxin in MT-I/II knock out (-/-) and wild type (WT) mice.

METHODS

MT (-/-) and WT mice were given vehicle or lipopolysaccharide (LPS, 125 microg/kg) intratracheally and the cellular profile of the bronchoalveolar lavage (BAL) fluid, pulmonary oedema, lung histology, expression of proinflammatory molecules, and nuclear localisation of nuclear factor-kappaB (NF-kappaB) in the lung were evaluated.

RESULTS

MT (-/-) mice were more susceptible than WT mice to lung inflammation, especially to lung oedema induced by intratracheal challenge with LPS. After LPS challenge, MT deficiency enhanced vacuolar degeneration of pulmonary endothelial cells and type I alveolar epithelial cells and caused focal loss of the basement membrane. LPS treatment caused no significant differences in the enhanced expression of proinflammatory cytokines and chemokines nor in the activation of the NF-kappaB pathway in the lung between the two genotypes. Lipid peroxide levels in the lungs were significantly higher in LPS treated MT (-/-) mice than in LPS treated WT mice.

CONCLUSIONS

Endogenous MT protects against acute lung injury related to LPS. The effects are possibly mediated by the enhancement of pulmonary endothelial and epithelial integrity, not by the inhibition of the NF-kappaB pathway.

Influenza and pneumococcal vaccination of the elderly in Taiwan

In 1998, Taiwan became the first country in Asia to provide free influenza vaccination to high-risk groups, mainly the elderly. The purpose of this study is to determine: (1) the annual mortality rate from influenza and pneumococcal-related illnesses such as pneumonia, chronic bronchitis, pulmonary emphysema and asthma and (2) the effectiveness of and adverse events associated with the influenza vaccination. In the elderly, influenza vaccination caused the annual death rate due chronic bronchitis, pulmonary emphysema, and asthma to decline steadily but had no effect on the annual pneumonia death rate. The only adverse effect of concern was vertigo (in approximately 2-3%).

A placebo-controlled trial of two intranasal vaccines to prevent tracheobronchitis (kennel cough) in dogs entering a humane shelter

A placebo-controlled field trial was conducted to compare the effectiveness of intranasal (IN) vaccines containing Bordetella bronchiseptica and canine-parainfluenza virus, with (IN-BPA) or without (IN-BP) canine-adenovirus type 2, for prevention of kennel cough at a humane shelter. Dogs were examined on admission to the shelter and those without respiratory signs of disease were assigned daily, on a rotating basis, to receive one of three vaccines. We enrolled 972 healthy dogs. Dogs were monitored for up to 30 days post-vaccination for coughing and other clinical signs of respiratory disease. Thirty-three (10.7%; 95% confidence interval (CI): 7.2, 14.2) dogs in the IN-BP group, 36 (10.2%; 95% CI: 7.0, 13.4) dogs in the IN-BPA group, and 42 (13.5%; 95% CI: 9.7, 17.3) dogs in the IN-P group coughed spontaneously for ≥1 day within 30 days of vaccination (P=0.37). The IN-BP and IN-BPA vaccines were 20.7 and 24.4% effective, respectively, in reducing coughing compared with a placebo vaccine. The strongest prognostic factor for coughing (regardless of vaccine group) was the number of days spent at the shelter, with each additional day increasing the risk of coughing by 3% (95% CI: 0.5, 6.3). The low incidence of coughing in the shelter during this study precluded observation of differences in vaccine effectiveness. No differences in vaccine-associated adverse events (coughing, sneezing, nasal or ocular discharge) were noted during the first 3 days post-administration or thereafter.

[Antibiotics in lower respiratory tract infection]

THE AIM OF THE STUDY

Comparison of clinical outcome of lower respiratory tract infections in small children treated or not treated with antibiotics.

MATERIAL AND METHODS

Eighty seven children aged from 2 months to 5 years admitted to hospital with mild to moderate bronchitis and/or pneumonia were randomly allocated to one of two groups: group A children were treated with antibiotics and group B patients were not. The children remained under close clinical observation. The clinical outcome was considered good if symptoms of the disease decreased after 72 hours. In case of no clinical improvement or worsening, the children from group B received antibiotics and in children from group A antibiotic therapy was changed.

RESULTS AND CONCLUSIONS

There were no significant differences between the two groups in the course of the disease, the frequency of pulmonary complications and recurrence during one month of follow-up.

Respiratory epithelial cells regulate lung inflammation in response to inhaled endotoxin

To determine the role of respiratory epithelial cells in the inflammatory response to inhaled endotoxin, we selectively inhibited NF-kappa B activation in the respiratory epithelium using a mutant I kappa B-alpha construct that functioned as a dominant negative inhibitor of NF-kappa B translocation (dnI kappa B-alpha). We developed two lines of transgenic mice in which expression of dnI kappa B-alpha was targeted to the distal airway epithelium using the human surfactant apoprotein C promoter. Transgene expression was localized to the epithelium of the terminal bronchioles and alveoli. After inhalation of LPS, nuclear translocation of NF-kappa B was evident in bronchiolar epithelium of nontransgenic but not of transgenic mice. This defect was associated with impaired neutrophilic lung inflammation 4 h after LPS challenge and diminished levels of TNF-alpha, IL-1 beta, macrophage inflammatory protein-2, and KC in lung homogenates. Expression of TNF-alpha within bronchiolar epithelial cells and of VCAM-1 within peribronchiolar endothelial cells was reduced in transgenic animals. Thus targeted inhibition of NF-kappa B activation in distal airway epithelial cells impaired the inflammatory response to inhaled LPS. These data provide causal evidence that distal airway epithelial cells and the signals they transduce play a physiological role in lung inflammation in vivo.