Airway epithelial cell apoptosis and inflammation in COPD, smokers and non-smokers

We hypothesised that primary bronchial epithelial cells (PBECs) from subjects with COPD respond differently to Pseudomonas aeruginosa lipopolysaccharide (PA LPS) after cigarette smoke extract (CSE) exposure than PBECs obtained from smokers without airflow obstruction (SWAO) and non-smokers (NS).PBECs from 16 COPD subjects, 10 SWAOand 9 NS were cultured at air-liquid interface. Cultures were incubated with CSE prior to stimulation with PA LPS. IL-6 and IL-8 were measured by ELISA and Toll-like receptor 4 expression by FACS. Activation of NF-?B was determined by western blotting and ELISA, and MAPK and caspase-3 activity by western blotting. Apoptosis was evaluated using Annexin-V staining and the terminal transferase-mediated dUTP nick end-labeling (TUNEL) methods.Constitutive release of IL-8 and IL-6 was greatest from the COPD cultures.However, CSE pre-treatment followed by PA LPS stimulation reduced IL-8 release from COPD PBECs, but increased it from cells of SWAOand NS. TLR-4 expression,MAPK and NF-?B activation in COPD cultures were reduced after CSE treatment, but not in the SWAOor NS groups, which was associated with increased apoptosis.CSE attenuates inflammatory responses to LPS in cells from people with COPD but not those from non-smoking individuals and those who smoke without airflow obstruction.

Millimeter-wave and submillimeter-wave imaging for security and surveillance

Passive equipments operating in the 30-300 GHZ (millimeter wave) band are compared to those in the 300 GHz-3 THz (submillimeter band). Equipments operating in the submillimeter band can measure distance and also spectral information and have been used to address new opportunities in security. Solid state spectral information is available in the submillimeter region making it possible to identify materials, whereas in millimeter region bulk optical properties determine the image contrast. The optical properties in the region from 30 GHz to 3 THz are discussed for some typical inorganic and organic solids. in the millimeter-wave region of the spectrum, obscurants such as poor weather, dust, and smoke can be penetrated and useful imagery generated for surveillance. in the 30 GHZ-3 THZ region dielectrics such as plastic and cloth are also transparent and the detection of contraband hidden under clothing is possible. A passive millimeter-wave imaging concept based on a folded Schmidt camera has been developed and applied to poor weather navigation and security. The optical design uses a rotating mirror and is folded using polarization techniques. The design is very well corrected over a wide field of view making it ideal for surveillance, and security. This produces a relatively compact imager which minimizes the receiver count.

Explaining Social Class Inequalities in Smoking: The Role of Education, Self-Efficacy, and Deprivation

Rates of smoking have decreased dramatically in most Northern European countries over the last 50 years or so, but manual working class groups are substantially more likely to smoke daily than are the professional and managerial classes. This article examines three hypotheses about the processes producing these inequalities. The first argues that social class inequalities reflect differences across education groups in knowledge of the risks of smoking. The second suggests that the living conditions of lower social class groups leads to the development of lower self-efficacy and a lower propensity to quit smoking. The third states that smoking has a functional use among poorer individuals. This article draws upon data from the Republic of Ireland to assess these hypotheses. Our analysis provides some support for the first hypothesis in that education independently reduces the odds of a manual class person smoking relative to a non-manual by 12 per cent. The second hypothesis is not supported by the data. The third hypothesis gains the most support: measures of disadvantage and deprivation account for almost one-third of the class differential in smoking. The results suggest that smoking cessation policy should reflect the importance of social and economic context in quitting behaviour.

Impact of cigarette smoke exposure on host-bacterial pathogen interactions

The human respiratory tract of individuals with normal lung function maintains a fine-tuned balance, being asymptomatically colonised by the normal microbiota in the upper airways and sterile in the lower tract. This equilibrium may be disrupted by the exposure to insults such as cigarette smoke. In the respiratory tract, the complex and noxious nature of inhaled cigarette smoke alters host-microorganisminteraction dynamics at all anatomical levels, causing infections in many cases. Moreover, continuous exposure to cigarette smoke itself causes deleterious effects on the host that can trigger the development of chronic respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and lung cancer. COPD is an irreversible airflow obstruction associated with emphysema, fibrosis, mucus hypersecretion and persistent colonisation of the lower airways by opportunistic pathogens. COPD patients keep a stable (without exacerbation) but progressively worsening condition and suffer periodic exacerbations caused, in most cases, by infections. Although smoking and smoking-associated diseases are associated with a high risk of infection, most therapies aim to reduce inflammatory parameters, but do not necessarily take into account the presence of persistent colonisers. The effect of cigarette smoke on host-pathogen interaction dynamics in the respiratory tract, together with current and novel therapies, is discussed. Copyright©ERS 2012.

Lipopolysaccharide-binding protein and CD14 are increased in the bronchoalveolar lavage fluid of smokers

Lipopolysaccharide-binding protein (LBP) and CD14 contribute to the recognition of pathogens by cells, which triggers the activation of defence responses. Smoking is a risk factor for the development of chronic obstructive pulmonary disease (COPD) and respiratory infections. The current authors theorised that levels of LBP and CD14 in the lungs of smokers would be higher than those in the lungs of never-smokers. These elevated levels could affect host responses upon infection. LBP, soluble CD14 (sCD14) and interleukin (IL)-8 were detected by ELISA. Nuclear factor (NF)- ?B, p38 and the inhibitor I?Ba were studied by immunoassays. Gene expression was assessed by RT-PCR. Bronchoalveolar lavage levels of LBP and CD14 were significantly higher in smokers and COPD patients than in never-smokers, whereas levels of both proteins were not significantly different between smokers and COPD patients. IL-6, IL-1ß5 and cigarette smoke condensate induced the expression of LBP and CD14 by airway epithelial cells. LBP and sCD14 inhibited the nontypeable Haemophilus influenzae (NTHi)-dependent secretion of IL-8 and the activation of NF-?B and p38 mitogen-activated protein kinase signalling pathways but they increased the internalisation of NTHi by airway epithelial cells. Thus, in the inflamed airways of smokers both proteins could contribute to inhibit bacteria-dependent cellular activation without compromising the internalisation of pathogens by airway cells. Copyright©ERS Journals Ltd 2009.

Nontypeable Haemophilus influenzae clearance by alveolar macrophages is impaired by exposure to cigarette smoke

Nontypeable Haemophilus influenzae (NTHI) is an opportunistic gram-negative pathogen that causes respiratory infections and is associated with progression of respiratory diseases. Cigarette smoke is a main risk factor for development of respiratory infections and chronic respiratory diseases. Glucocorticoids, which are anti-inflammatory drugs, are still the most common therapy for these diseases. Alveolar macrophages are professional phagocytes that reside in the lung and are responsible for clearing infections by the action of their phagolysosomal machinery and promotion of local inflammation. In this study, we dissected the interaction between NTHI and alveolar macrophages and the effect of cigarette smoke on this interaction. We showed that alveolar macrophages clear NTHI infections by adhesion, phagocytosis, and phagolysosomal processing of the pathogen. Bacterial uptake requires host actin polymerization, the integrity of plasma membrane lipid rafts, and activation of the phosphatidylinositol 3-kinase (PI3K) signaling cascade. Parallel to bacterial clearance, macrophages secrete tumor necrosis factor alpha (TNF-alpha) upon NTHI infection. In contrast, exposure to cigarette smoke extract (CSE) impaired alveolar macrophage phagocytosis, although NTHI-induced TNF-alpha secretion was not abrogated. Mechanistically, our data showed that CSE reduced PI3K signaling activation triggered by NTHI. Treatment of CSE-exposed cells with the glucocorticoid dexamethasone reduced the amount of TNF-alpha secreted upon NTHI infection but did not compensate for CSE-dependent phagocytic impairment. The deleterious effect of cigarette smoke was observed in macrophage cell lines and in human alveolar macrophages obtained from smokers and from patients with chronic obstructive pulmonary disease.

Consistency of arsenic speciation in global tobacco products with implications for health and regulation

Background: Tobacco smoke is a major risk to the health of its users and arsenic is among the components of smoke present at concentrations of toxicological concern. There are significant variations in human toxicity between inorganic and organic arsenic species and the aim of this study was to determine whether there are predictable relationships among major arsenic species in tobacco that could be useful for risk assessment.

Methods: 14 samples of tobacco were studied spanning a wide range of concentrations in samples from different geographical regions, including certified reference materials and cigarette products. Inorganic and major organic arsenic species were extracted from powdered tobacco samples by nitric acid using microwave digestion. Concentrations of arsenic species in these extracts were determined using HPLC-ICPMS.

Results: The concentrations of total inorganic arsenic species range from 144 to 3914 mu g kg(-1), while organic species dimethylarsinic acid (DMA) ranges from 21 to 176 mu g As kg(-1), and monomethylarsonic acid (MA) ranges from 30 to 116 mu g kg(-1). The percentage of species eluted compared to the total arsenic extracted ranges from 11.1 to 36.8% suggesting that some As species (possibly macro-molecules, strongly complexed or in organic forms) do not elute from the column. This low percentage of column-speciated arsenic is indicative that more complex forms of arsenic exist in the tobacco. All the analysed species correlate positively with total arsenic concentration over the whole compositional range and regression analysis indicates a consistent ratio of about 4:1 in favour of inorganic arsenic compared with MA + DMA.

Conclusions: The dominance of inorganic arsenic species among those components analysed is a marked feature of the diverse range of tobaccos selected for study. Such consistency is important in the context of a WHO expert panel recommendation to regulate tobacco crops and products using total arsenic concentration. If implemented more research would be required to develop models that accurately predict the smoker's exposure to reduced inorganic arsenic species on the basis of leaf or product concentration and product design features.

The impact of parental migration on health status and health behaviours among left behind adolescent school children in China.

BACKGROUND:

One out of ten of China's population are migrants, moving from rural to urban areas. Many leave their families behind resulting in millions of school children living in their rural home towns without one or both their parents. Little is known about the health status of these left behind children (LBC). This study compares the health status and health-related behaviours of left behind adolescent school children and their counterparts in a rural area in Southern China.

METHODS:

A cross-sectional study was conducted among middle school students in Fuyang Township, Guangdong, China (2007-2008). Information about health behaviours, parental migration and demographic characteristics was collected using a self-administered questionnaire. Overweight/obesity and stunting were defined based on measurements of height and weight. Univariate and multivariate analyses were used to estimate the differences in health outcomes between LBC and non-LBC.

RESULTS:

18.1% of the schoolchildren had one or both parents working away from home. Multivariate analysis showed that male LBC were at higher risk of skipping breakfast, higher levels of physical inactivity, internet addiction, having ever smoked tobacco, suicide ideation, and being overweight. LBC girls were more likely to drink excessive amounts of sweetened beverage, to watch more TV, to have ever smoked or currently smoke tobacco, to have ever drunk alcohol and to binge drinking. They were also more likely to be unhappy, to think of planning suicide and consider leaving home.

CONCLUSIONS:

Our findings suggest that parental migration is a risk factor for unhealthy behaviours amongst adolescent school children in rural China. Further research is required in addition to the consideration of the implications for policies and programmes to protect LBC.