Key mechanisms governing resolution of lung inflammation

Innate immunity normally provides excellent defence against invading microorganisms. Acute inflammation is a form of innate immune defence and represents one of the primary responses to injury, infection and irritation, largely mediated by granulocyte effector cells such as neutrophils and eosinophils. Failure to remove an inflammatory stimulus (often resulting in failed resolution of inflammation) can lead to chronic inflammation resulting in tissue injury caused by high numbers of infiltrating activated granulocytes. Successful resolution of inflammation is dependent upon the removal of these cells. Under normal physiological conditions, apoptosis (programmed cell death) precedes phagocytic recognition and clearance of these cells by, for example, macrophages, dendritic and epithelial cells (a process known as efferocytosis). Inflammation contributes to immune defence within the respiratory mucosa (responsible for gas exchange) because lung epithelia are continuously exposed to a multiplicity of airborne pathogens, allergens and foreign particles. Failure to resolve inflammation within the respiratory mucosa is a major contributor of numerous lung diseases. This review will summarise the major mechanisms regulating lung inflammation, including key cellular interplays such as apoptotic cell clearance by alveolar macrophages and macrophage/neutrophil/epithelial cell interactions. The different acute and chronic inflammatory disease states caused by dysregulated/impaired resolution of lung inflammation will be discussed. Furthermore, the resolution of lung inflammation during neutrophil/eosinophil-dominant lung injury or enhanced resolution driven via pharmacological manipulation will also be considered

Heterogeneity and changes in preferences for dying at home:a systematic review

Background Home-based models of hospice and palliative care are promoted with the argument that most people prefer to die at home. We examined the heterogeneity in preferences for home death and explored, for the first time, changes of preference with illness progression. Methods We searched for studies on adult preferences for place of care at the end of life or place of death in MEDLINE (1966-2011), EMBASE (1980-2011), psycINFO (1967-2011), CINAHL (1982-2011), six palliative care journals (2006-11) and reference lists. Standard criteria were used to grade study quality and evidence strength. Scatter plots showed the percentage preferring home death amongst patients, lay caregivers and general public, by study quality, year, weighted by sample size. Results 210 studies reported preferences of just over 100,000 people from 33 countries, including 34,021 patients, 19,514 caregivers and 29,926 general public members. 68% of studies with quantitative data were of low quality; only 76 provided the question used to elicit preferences. There was moderate evidence that most people prefer a home death-this was found in 75% of studies, 9/14 of those of high quality. Amongst the latter and excluding outliers, home preference estimates ranged 31% to 87% for patients (9 studies), 25% to 64% for caregivers (5 studies), 49% to 70% for the public (4 studies). 20% of 1395 patients in 10 studies (2 of high quality) changed their preference, but statistical significance was untested. Conclusions Controlling for methodological weaknesses, we found evidence that most people prefer to die at home. Around four fifths of patients did not change preference as their illness progressed. This supports focusing on home-based care for patients with advanced illness yet urges policy-makers to secure hospice and palliative care elsewhere for those who think differently or change their mind. Research must be clear on how preferences are elicited. There is an urgent need for studies examining change of preferences towards death