The influence of neighbourhood disadvantage on smoking cessation and its contribution to inequalities in smoking status

Introduction and aims: Individual smokers from disadvantaged backgrounds are less likely to quit, which contributes to widening inequalities in smoking. Residents of disadvantaged neighbourhoods are more likely to smoke, and neighbourhood inequalities in smoking may also be widening because of neighbourhood differences in rates of cessation. This study examined the association between neighbourhood disadvantage and smoking cessation and its relationship with neighbourhood inequalities in smoking. Design and methods: A multilevel longitudinal study of mid-aged (40-67 years) residents (n=6915) of Brisbane, Australia, who lived in the same neighbourhoods (n=200) in 2007 and 2009. Neighbourhood inequalities in cessation and smoking were analysed using multilevel logistic regression and Markov chain Monte Carlo simulation. Results: After adjustment for individual-level socioeconomic factors, the probability of quitting smoking between 2007 and 2009 was lower for residents of disadvantaged neighbourhoods (9.0%-12.8%) than their counterparts in more advantaged neighbourhoods (20.7%-22.5%). These inequalities in cessation manifested in widening inequalities in smoking: in 2007 the between-neighbourhood variance in rates of smoking was 0.242 (p≤0.001) and in 2009 it was 0.260 (p≤0.001). In 2007, residents of the most disadvantaged neighbourhoods were 88% (OR 1.88, 95% CrI 1.41-2.49) more likely to smoke than residents in the least disadvantaged neighbourhoods: the corresponding difference in 2009 was 98% (OR 1.98 95% CrI 1.48-2.66). Conclusion: Fundamentally, social and economic inequalities at the neighbourhood and individual-levels cause smoking and cessation inequalities. Reducing these inequalities will require comprehensive, well-funded, and targeted tobacco control efforts and equity based policies that address the social and economic determinants of smoking.

Ventilation distribution in rats : Part I - The effect of gas composition as measured with electrical impedance tomography

The measurement of ventilation distribution is currently performed using inhaled tracer gases for multiple breath inhalation studies or imaging techniques to quantify spatial gas distribution. Most tracer gases used for these studies have properties different from that of air. The effect of gas density on regional ventilation distribution has not been studied. This study aimed to measure the effect of gas density on regional ventilation distribution. Methods Ventilation distribution was measured in seven rats using electrical impedance tomography (EIT) in supine, prone, left and right lateral positions while being mechanically ventilated with either air, heliox (30% oxygen, 70% helium) or sulfur hexafluoride (20% SF6, 20% oxygen, 60% air). The effect of gas density on regional ventilation distribution was assessed. Results Gas density did not impact on regional ventilation distribution. The non-dependent lung was better ventilated in all four body positions. Gas density had no further impact on regional filling characteristics. The filling characteristics followed an anatomical pattern with the anterior and left lung showing a greater impedance change during the initial phase of the inspiration. Conclusion It was shown that gas density did not impact on convection dependent ventilation distribution in rats measured with EIT.

Extracorporeal lessons from sheep

Background: Extracorporeal circulation (ECC), the diversion of blood flow through a circuit located outside of the body, has been one of the major advances in modern medicine. Cardio-pulmonary bypass (CPB), renal dialysis, apheresis and extracorporeal membrane oxygenation (ECMO) are all different forms of ECC. Despite its major benefits, when blood comes into contact with foreign material, both the coagulation and inflammation cascades are activated simultaneously. Short periods of exposure to ECC e.g. CPB (�2 h duration), are known to be associated with haemolysis, coagulopathies, bleeding and inflammation which demand blood product support. Therefore, it is not unexpected that these complications would be exaggerated with prolonged periods of ECC such as in ECMO (days to weeks duration). The variability and complexities of the underlying pathologies of patients requiring ECC makes it difficult to study the cause and effect of these complications. To overcome this problem we developed an ovine (sheep) model of ECC. Method: Healthy female sheep (1–3 y.o.) weighing 40–50 kg were fasted overnight, anaesthetised, intubated and ventilated [1]. Half the group received smoke induced acute lung injury (S-ALI group) (n = 8) and the other half did not (healthy group) (n = 8). Sheep were subsequently cannulated (Medtronic Inc, Minneapolis, MN, USA) and veno-venous ECMO commenced using PLS ECMO circuit and Quadrox D oxygenator (Maquet Cardiopulmonary AG, Hechinger Straße, Germany). There was continuous physiological monitoring and blood was collected at specified time intervals for full blood counts, platelet function analysis (by Multiplate®), routine coagulation and assessment of clot formation and lysis (by ROTEM®). Preliminary results Full blood counts and routine coagulation results from normal healthy sheep were comparable to those of normal human adults. Within 15 min of initiating of ECMO, PT, PTT and EXTEM clot formation time increased, whilst EXTEM maximum clot firmness decreased in both cohorts. Discussion & Conclusions: Preliminary results of sheep from both 2 h ECMO cohorts showed that the anatomy, haematology and coagulation parameters of an adult sheep are comparable to that a human adult. Experiments are currently underway with healthy (n = 8) and S-ALI (n = 8) sheep on ECMO for 24 h. In addition to characterising how ECMO alters haematology and coagulation parameters, we hope that it will also define which blood components will be most effective to correct bleeding or clotting complications during ECMO support.

Application of profluorescent nitroxides for measurements of oxidative capacity of combustion generated particles

Oxidative stress caused by generation of free radicals and related reactive oxygen species (ROS) at the sites of deposition has been proposed as a mechanism for many of the adverse health outcomes associated with exposure to particulate matter (PM). Recently, a new profluorescent nitroxide molecular probe (BPEAnit) developed at QUT was applied in an entirely novel, rapid and non-cell based assay for assessing the oxidative potential of particles (i.e. potential of particles to induce oxidative stress). The technique was applied on particles produced by several combustion sources, namely cigarette smoke, diesel exhaust and wood smoke. One of the main findings from the initial studies undertaken at QUT was that the oxidative potential per PM mass significantly varies for different combustion sources as well as the type of fuel used and combustion conditions. However, possibly the most important finding from our studies was that there was a strong correlation between the organic fraction of particles and the oxidative potential measured by the PFN assay, which clearly highlights the importance of organic species in particle-induced toxicity.

Rates of attendance at a smoking cessation clinic within a cardiac rehabilitation service

Objectives: Smoking cessation has been shown to be an important intervention for preventing cardiovascular events and improving the health of patients with heart disease. However, unaided quit attempts in these patients often leads to high rates of failure and a return to smoking. Outpatient smoking cessation clinics using face-to-face counseling, ongoing behavioral support, advice on smoking pharmacotherapy and objective monitoring, have been found to be one of the most effective interventions for improving quit smoking rates. An outpatient smoking cessation clinic was trialed within a cardiac rehabilitation service in order to explore its effects on smoking rates for patients with or at risk of heart disease. Attendance rates to the clinic were also monitored. Methods: A descriptive exploratory design was used for this newly developed clinic. Patients who currently smoked tobacco and who had a history of either coronary artery disease, heart failure, atrial fibrillation or those seen under a chest pain assessment service were invited to an outpatient ‘Cardiac Patients Smokers Clinic’. Initially patients were offered up to 10 clinic visits over a 3 month period. Follow-up clinic visits were conducted at 3, 6 and 12 months. A portable carbon monoxide meter was used to objectively measure levels of smoking and validate smoking abstinence. Primary outcomes included rates of attendance. Results: Preliminary findings showed 24 per cent of participants (N = 6) completed all their clinic visits and remained smoke free as measured by their ongoing expired carbon monoxide readings. Clinic attendance rates appeared lowest for those with significant mental health issues such as schizophrenia or substance abuse. However, rates of attendance were improved by having an administration officer make reminder telephone calls prior to clinic visits. Conclusions: Early findings indicate the feasibility of providing a specialist smoking cessation clinic within a cardiac rehabilitation service. Further, that reminder telephone calls prior to appointments improved attendance rates in patients with heart disease to this type of clinic. However, future investigations are warranted.

Indoor aerosols : from personal exposure to risk assessment

Motivated by growing considerations of the scale, severity and risks associated with human exposure to indoor particulate matter, this work reviewed existing literature to: (i) identify state-of-the-art experimental techniques used for personal exposure assessment; (ii) compare exposure levels reported for domestic/school settings in different countries (excluding exposure to environmental tobacco smoke and particulate matter from biomass cooking in developing countries); (iii) assess the contribution of outdoor background vs indoor sources to personal exposure; and (iv) examine scientific understanding of the risks posed by personal exposure to indoor aerosols. Limited studies assessing integrated daily residential exposure to just one particle size fraction, ultrafine particles, show that the contribution of indoor sources ranged from 19-76%. This indicates a strong dependence on resident activities, source events and site specificity, and highlights the importance of indoor sources for total personal exposure. Further, it was assessed that 10-30% of the total burden-of-disease from particulate matter exposure was due to indoor generated particles, signifying that indoor environments are likely to be a dominant environmental factor affecting human health. However, due to challenges associated with conducting epidemiological assessments, the role of indoor generated particles has not been fully acknowledged, and improved exposure/risk assessment methods are still needed, together with a serious focus on exposure control.

Perceptions and attitudes of nursing students’ towards electronic health records

Introduction The onset of Personally Controlled Electronic Health Records in Australia demand healthcare decision making processes to comprise, understand and accept electronic health records (EHR). Nurses play a key, central role in the healthcare decision making process and their perceptions and attitudes of EHRs are significant [1], which develop during their academic life. However, studies aimed at nursing students’ attitudes of EHRs are very limited [2-4]. A proper understanding of these attitudes and how they evolve with academic progress is important. This paper presents results from a survey conducted at a leading University in Queensland, Australia as a first step to filling this gap.

Cell migration and proliferation on homogeneous and non-homogeneous domains : modelling on the scale of individuals and populations

Cell migration is a behaviour critical to many key biological effects, including wound healing, cancerous cell invasion and morphogenesis, the development of an organism from an embryo. However, given that each of these situations is distinctly different and cells are extremely complicated biological objects, interest lies in more basic experiments which seek to remove conflating factors and present a less complex environment within which cell migration can be experimentally examined. These include in vitro studies like the scratch assay or circle migration assay, and ex vivo studies like the colonisation of the hindgut by neural crest cells. The reduced complexity of these experiments also makes them much more enticing as problems to mathematically model, like done here. The primary goal of the mathematical models used in this thesis is to shed light on which cellular behaviours work to generate the travelling waves of invasion observed in these experiments, and to explore how variations in these behaviours can potentially predict differences in this invasive pattern which are experimentally observed when cell types or chemical environment are changed. Relevant literature has already identified the difficulty of distinguishing between these behaviours when using traditional mathematical biology techniques operating on a macroscopic scale, and so here a sophisticated individual-cell-level model, an extension of the Cellular Potts Model (CPM), is been constructed and used to model a scratch assay experiment. This model includes a novel mechanism for dealing with cell proliferations that allowed for the differing properties of quiescent and proliferative cells to be implemented into their behaviour. This model is considered both for its predictive power and used to make comparisons with the travelling waves which result in more traditional macroscopic simulations. These comparisons demonstrate a surprising amount of agreement between the two modelling frameworks, and suggest further novel modifications to the CPM that would allow it to better model cell migration. Considerations of the model’s behaviour are used to argue that the dominant effect governing cell migration (random motility or signal-driven taxis) likely depends on the sort of invasion demonstrated by cells, as easily seen by microscopic photography. Additionally, a scratch assay simulated on a non-homogeneous domain consisting of a ’fast’ and ’slow’ region is also used to further differentiate between these different potential cell motility behaviours. A heterogeneous domain is a novel situation which has not been considered mathematically in this context, nor has it been constructed experimentally to the best of the candidate’s knowledge. Thus this problem serves as a thought experiment used to test the conclusions arising from the simulations on homogeneous domains, and to suggest what might be observed should this non-homogeneous assay situation be experimentally realised. Non-intuitive cell invasion patterns are predicted for diffusely-invading cells which respond to a cell-consumed signal or nutrient, contrasted with rather expected behaviour in the case of random-motility-driven invasion. The potential experimental observation of these behaviours is demonstrated by the individual-cell-level model used in this thesis, which does agree with the PDE model in predicting these unexpected invasion patterns. In the interest of examining such a case of a non-homogeneous domain experimentally, some brief suggestion is made as to how this could be achieved.

The hazards of starting and quitting smoking: Some Australian evidence

The empirical analysis employs individual level data from the Australian Health Survey combined with retrospective data on tobacco price matched to the age at which the individual started and quit smoking. Split-population hazard models are estimated for both starting and quitting smoking. The analysis suggests price plays a significant role in the decision to start smoking but not in the decision to quit. Further sensitivity analysis of different age groups and an alternative data source, questions the robustness of the significant role of price in the smoking initiation decision. From a policy perspective, the results indicate that increases in tobacco taxation can be an important instrument in reducing the incidence of smoking, but should be combined with other mechanisms such as mandating smoke-free environments and antismoking education. Our results strongly support the targeting of antismoking campaigns towards teenagers.

Changing parental high risk behaviour in the reduction of SIDS : the imperative of translational research

Objectives To investigate the factors associated with sudden infant death syndrome (SIDS) from birth to age 2 years, whether recent advice has been followed, whether any new risk factors have emerged, and the specific circumstances in which SIDS occurs while cosleeping (infant sharing the same bed or sofa with an adult or child). Design Four year population based case-control study. Parents were interviewed shortly after the death or after the reference sleep (within 24 hours) of the two control groups. Setting South west region of England (population 4.9 million, 184 800 births). Participants 80 SIDS infants and two control groups weighted for age and time of reference sleep: 87 randomly selected controls and 82 controls at high risk of SIDS (young, socially deprived, multiparous mothers who smoked). Results The median age at death (66 days) was more than three weeks less than in a study in the same region a decade earlier. Of the SIDS infants, 54% died while cosleeping compared with 20% among both control groups. Much of this excess may be explained by a significant multivariable interaction between cosleeping and recent parental use of alcohol or drugs (31% v 3% random controls) and the increased proportion of SIDS infants who had coslept on a sofa (17% v 1%). One fifth of SIDS infants used a pillow for the last sleep (21% v 3%) and one quarter were swaddled (24% v 6%). More mothers of SIDS infants than random control infants smoked during pregnancy (60% v 14%), whereas one quarter of the SIDS infants were preterm (26% v 5%) or were in fair or poor health for the last sleep (28% v 6%). All of these differences were significant in the multivariable analysis regardless of which control group was used for comparison. The significance of covering the infant’s head, postnatal exposure to tobacco smoke, dummy use, and sleeping in the side position has diminished although a significant proportion of SIDS infants were still found prone (29% v 10%). Conclusions Many of the SIDS infants had coslept in a hazardous environment. The major influences on risk, regardless of markers for socioeconomic deprivation, are amenable to change and specific advice needs to be given, particularly on use of alcohol or drugs before cosleeping and cosleeping on a sofa.

A dynamic approach for evaluating earthwork hauls in construction

A graph theoretic approach is developed for accurately computing haulage costs in earthwork projects. This is vital as haulage is a predominant factor in the real cost of earthworks. A variety of metrics can be used in our approach, but a fuel consumption proxy is recommended. This approach is novel as it considers the constantly changing terrain that results from cutting and filling activities and replaces inaccurate “static” calculations that have been used previously. The approach is also capable of efficiently correcting the violation of top down cutting and bottom up filling conditions that can be found in existing earthwork assignments and sequences. This approach assumes that the project site is partitioned into uniform blocks. A directed graph is then utilised to describe the terrain surface. This digraph is altered after each cut and fill, in order to reflect the true state of the terrain. A shortest path algorithm is successively applied to calculate the cost of each haul and these costs are summed to provide a total cost of haulage

Case-control study on risk factors of esophageal cancer

Objective: To explore the influencing factors of esophageal cancer in the trunk basin of Dawen river , Shandong province. Methods: A case- control study was carried out: 195 living cases of diagnosed esophageal cancer and 195 controls were matched by age and sex and surveyed by a unified inventory. Results: T he following items could rises the risk of esophageal cancer : hard dry diet, smoke homemade cigarettes, alcohol consumption> 500 ml/ day, relatives with tumor in history ( OR = 51850, OR = 161 158, OR = 111 513, OR = 11 827, respectively ) . While drinking tea may have protective effect against esophageal cancer ( OR = 01 311). Conclusion: The high incidence of esophageal cancer in the area is relative not only to the environment and dietary factors, but also to the family history of esophageal cancer.

The role of inflammation in the pathogenesis of non-small cell lung cancer

The link between chronic immune activation and tumorigenesis is well established. Compelling evidence has accumulated that histologic assessment of infiltration patterns of different host immune response components in non-small cell lung cancer specimens helps identify different prognostic patient subgroups. This review provides an overview of recent insights gained in the understanding of the role played by chronic inflammation in lung carcinogenesis. The usefulness of quantification of different populations of lymphocytes, natural killer cells, macrophages, and mast cells within the tumor microenvironment in non-small cell lung cancer is also discussed. In particular, the importance of assessment of inflammatory cell microlocalization within both the tumor islet and surrounding stromal components is emphasized. Copyright © 2010 by the International Association for the Study of Lung Cancer.

In vitro assessment of surface congruency and integration of chondrocytes at adjacent edges of micro-fabricated clefts on cartilage

Osteochondral grafts are common treatment options for joint focal defects due to their excellent functionality. However, the difficulty is matching the topography of host and graft(s) surfaces flush to one another. Incongruence could lead to disintegration particularly when the gap reaches subchondoral region. The aim of this study is therefore to investigate cell response to gap geometry when forming cartilage-cartilage bridge at the interface. The question is what would be the characteristics of such a gap if the cells could bridge across to fuse the edges? To answer this, osteochondral plugs devoid of host cells were prepared through enzymatic decellularization and artificial clefts of different sizes were created on the cartilage surface using laser ablation. High density pellets of heterologous chondrocytes were seeded on the defects and cultured with chondrogenic differentiation media for 35 days. The results showed that the behavior of chondrocytes was a function of gap topography. Depending on the distance of the edges two types of responses were generated. Resident cells surrounding distant edges demonstrated superficial attachment to one side whereas clefts of 150 to 250 µm width experienced cell migration and anchorage across the interface. The infiltration of chondrocytes into the gaps provided extra space for their proliferation and laying matrix; as the result faster filling of the initial void space was observed. On the other hand, distant and fit edges created an incomplete healing response due to the limited ability of differentiated chondrocytes to migrate and incorporate within the interface. It seems that the initial condition of the defects and the curvature profile of the adjacent edges were the prime determinants of the quality of repair; however, further studies to reveal the underlying mechanisms of cells adapting to and modifying the new environment would be of particular interest.

Influence of kaolinite/carbon black hybridization on combustion and thermal decomposition behaviors of NR composites

A series of NR composites filled with modified kaolinite (MK), carbon black (CB) and the hybrid fillercontained MK and CB, were prepared by melt blending. The microstructure, combustion and thermaldecomposition behaviors of NR composites were characterized by TEM, XRD, infrared spectroscopy, conecalorimeter test (CCT) and thermal-gravimetric analysis (TG). The results show that the filler hybridizationcan improve the dispensability and shape of the kaolinite sheets in the rubber matrix and change theinterface bond between kaolinite particles and rubber molecules. NR-3 filled by 10 phr MK and 40 phr CBhas the lowest heat release rate (HRR), mass loss rate (MLR), total heat release (THR), smoke productionrate (SPR) and the highest char residue among all the NR composites. Therefore, the hybridization ofthe carbon black particles with the kaolinite particles can effectively improve the thermal stability andcombustion properties of NR composites.